2024-05-31 01:32:42

by Ross Philipson

Subject: [PATCH v9 00/19] x86: Trenchboot secure dynamic launch Linux kernel support

The larger focus of the TrenchBoot project (https://github.com/TrenchBoot) is to
enhance the boot security and integrity in a unified manner. The first area of
focus has been on the Trusted Computing Group's Dynamic Launch for establishing
a hardware Root of Trust for Measurement, also know as DRTM (Dynamic Root of
Trust for Measurement). The project has been and continues to work on providing
a unified means to Dynamic Launch that is a cross-platform (Intel and AMD) and
cross-architecture (x86 and Arm), with our recent involvment in the upcoming
Arm DRTM specification. The order of introducing DRTM to the Linux kernel
follows the maturity of DRTM in the architectures. Intel's Trusted eXecution
Technology (TXT) is present today and only requires a preamble loader, e.g. a
boot loader, and an OS kernel that is TXT-aware. AMD DRTM implementation has
been present since the introduction of AMD-V but requires an additional
component that is AMD specific and referred to in the specification as the
Secure Loader, which the TrenchBoot project has an active prototype in
development. Finally Arm's implementation is in specification development stage
and the project is looking to support it when it becomes available.

This patchset provides detailed documentation of DRTM, the approach used for
adding the capbility, and relevant API/ABI documentation. In addition to the
documentation the patch set introduces Intel TXT support as the first platform
for Linux Secure Launch.

A quick note on terminology. The larger open source project itself is called
TrenchBoot, which is hosted on Github (links below). The kernel feature enabling
the use of Dynamic Launch technology is referred to as "Secure Launch" within
the kernel code. As such the prefixes sl_/SL_ or slaunch/SLAUNCH will be seen
in the code. The stub code discussed above is referred to as the SL stub.

The Secure Launch feature starts with patch #2. Patch #1 was authored by Arvind
Sankar. There is no further status on this patch at this point but
Secure Launch depends on it so it is included with the set.

Links:

The TrenchBoot project including documentation:

https://trenchboot.org

The TrenchBoot project on Github:

https://github.com/trenchboot

Intel TXT is documented in its own specification and in the SDM Instruction Set volume:

https://www.intel.com/content/dam/www/public/us/en/documents/guides/intel-txt-software-development-guide.pdf
https://software.intel.com/en-us/articles/intel-sdm

AMD SKINIT is documented in the System Programming manual:

https://www.amd.com/system/files/TechDocs/24593.pdf

The TrenchBoot project provides a quick start guide to help get a system
up and running with Secure Launch for Linux:

https://github.com/TrenchBoot/documentation/blob/master/QUICKSTART.md

Patch set based on commit:

torvalds/master/ea5f6ad9ad9645733b72ab53a98e719b460d36a6

Thanks
Ross Philipson and Daniel P. Smith

Changes in v2:

- Modified 32b entry code to prevent causing relocations in the compressed
kernel.
- Dropped patches for compressed kernel TPM PCR extender.
- Modified event log code to insert log delimiter events and not rely
on TPM access.
- Stop extending PCRs in the early Secure Launch stub code.
- Removed Kconfig options for hash algorithms and use the algorithms the
ACM used.
- Match Secure Launch measurement algorithm use to those reported in the
TPM 2.0 event log.
- Read the TPM events out of the TPM and extend them into the PCRs using
the mainline TPM driver. This is done in the late initcall module.
- Allow use of alternate PCR 19 and 20 for post ACM measurements.
- Add Kconfig constraints needed by Secure Launch (disable KASLR
and add x2apic dependency).
- Fix testing of SL_FLAGS when determining if Secure Launch is active
and the architecture is TXT.
- Use SYM_DATA_START_LOCAL macros in early entry point code.
- Security audit changes:
- Validate buffers passed to MLE do not overlap the MLE and are
properly laid out.
- Validate buffers and memory regions used by the MLE are
protected by IOMMU PMRs.
- Force IOMMU to not use passthrough mode during a Secure Launch.
- Prevent KASLR use during a Secure Launch.

Changes in v3:

- Introduce x86 documentation patch to provide background, overview
and configuration/ABI information for the Secure Launch kernel
feature.
- Remove the IOMMU patch with special cases for disabling IOMMU
passthrough. Configuring the IOMMU is now a documentation matter
in the previously mentioned new patch.
- Remove special case KASLR disabling code. Configuring KASLR is now
a documentation matter in the previously mentioned new patch.
- Fix incorrect panic on TXT public register read.
- Properly handle and measure setup_indirect bootparams in the early
launch code.
- Use correct compressed kernel image base address when testing buffers
in the early launch stub code. This bug was introduced by the changes
to avoid relocation in the compressed kernel.
- Use CPUID feature bits instead of CPUID vendor strings to determine
if SMX mode is supported and the system is Intel.
- Remove early NMI re-enable on the BSP. This can be safely done later
on the BSP after an IDT is setup.

Changes in v4:
- Expand the cover letter to provide more context to the order that DRTM
support will be added.
- Removed debug tracing in TPM request locality funciton and fixed
local variable declarations.
- Fixed missing break in default case in slmodule.c.
- Reworded commit messages in patches 1 and 2 per suggestions.

Changes in v5:
- Comprehensive documentation rewrite.
- Use boot param loadflags to communicate Secure Launch status to
kernel proper.
- Fix incorrect check of X86_FEATURE_BIT_SMX bit.
- Rename the alternate details and authorities PCR support.
- Refactor the securityfs directory and file setup in slmodule.c.
- Misc. cleanup from internal code reviews.
- Use reverse fir tree format for variables.

Changes in v6:
- Support for the new Secure Launch Resourse Table that standardizes
the information passed and forms the ABI between the pre and post
launch code.
- Support for booting Linux through the EFI stub entry point and
then being able to do a Secure Launch once EFI stub is done and EBS
is called.
- Updates to the documentation to reflect the previous two items listed.

Changes in v7:
- Switch to using MONITOR/MWAIT instead of NMIs to park the APs for
later bringup by the SMP code.
- Use static inline dummy functions instead of macros when the Secure
Launch feature is disabled.
- Move early SHA1 code to lib/crypto and pull it in from there.
- Numerous formatting fixes from comments on LKML.
- Remove efi-stub/DL stub patch temporarily for redesign/rework.

Changes in v8:
- Reintroduce efi-stub Linux kernel booting through the dynamic launch
stub (DL stub).
- Add new approach to setting localities > 0 through kernel and sysfs
interfaces in the TPM mainline driver.
- General code cleanup from v7 post comments.

Changes in v9:
- Updated DL stub support for recent changes to EFI stub in the kernel.
- Added patches to fix locality changing support in the TPM driver
(these patches originally were posted as a separate set).
- Enhanced Secure Launch TPM locality 2 setting in the TPM driver.
- Added locality setting support through sysfs for user land to access.
- Split up SHA1 and SHA256 changes into separate patches and updated
the commit messages to be more clear (per request from upstream
review).
- Fix Clang compile issues detected by kernel test robot.
- Modifications to the Secure Launch Resource Table ABI:
. Use flex arrays in table structures.
. Update and move fields in tables to make everything 8b aligned.
. Add 2 new DLME fields and a txt_heap address field.
. Remove platform specific tables that are not defined yet (AMD/ARM).
- Update Kconfig dependencies for Secure Launch with SHA1/SHA256/TPM.
- Remove push/pop of rsi since boot params is now stored in r15.
- Update outdated kernel documentation.
- Misc. comment fixes for type-os and mispellings.

Arvind Sankar (1):
x86/boot: Place kernel_info at a fixed offset

Daniel P. Smith (6):
x86: Add early SHA-1 support for Secure Launch early measurements
x86: Add early SHA-256 support for Secure Launch early measurements
tpm: Protect against locality counter underflow
tpm: Ensure tpm is in known state at startup
tpm: Make locality requests return consistent values
x86: Secure Launch late initcall platform module

Ross Philipson (12):
Documentation/x86: Secure Launch kernel documentation
x86: Secure Launch Kconfig
x86: Secure Launch Resource Table header file
x86: Secure Launch main header file
x86: Secure Launch kernel early boot stub
x86: Secure Launch kernel late boot stub
x86: Secure Launch SMP bringup support
kexec: Secure Launch kexec SEXIT support
reboot: Secure Launch SEXIT support on reboot paths
tpm: Add ability to set the preferred locality the TPM chip uses
tpm: Add sysfs interface to allow setting and querying the preferred
locality
x86: EFI stub DRTM launch support for Secure Launch

Documentation/arch/x86/boot.rst | 21 +
Documentation/security/index.rst | 1 +
.../security/launch-integrity/index.rst | 11 +
.../security/launch-integrity/principles.rst | 320 ++++++++
.../secure_launch_details.rst | 587 ++++++++++++++
.../secure_launch_overview.rst | 227 ++++++
arch/x86/Kconfig | 11 +
arch/x86/boot/compressed/Makefile | 3 +
arch/x86/boot/compressed/early_sha1.c | 12 +
arch/x86/boot/compressed/early_sha256.c | 6 +
arch/x86/boot/compressed/head_64.S | 30 +
arch/x86/boot/compressed/kernel_info.S | 53 +-
arch/x86/boot/compressed/kernel_info.h | 12 +
arch/x86/boot/compressed/sl_main.c | 577 ++++++++++++++
arch/x86/boot/compressed/sl_stub.S | 725 ++++++++++++++++++
arch/x86/boot/compressed/vmlinux.lds.S | 6 +
arch/x86/include/asm/msr-index.h | 5 +
arch/x86/include/asm/realmode.h | 3 +
arch/x86/include/uapi/asm/bootparam.h | 1 +
arch/x86/kernel/Makefile | 2 +
arch/x86/kernel/asm-offsets.c | 20 +
arch/x86/kernel/reboot.c | 10 +
arch/x86/kernel/setup.c | 3 +
arch/x86/kernel/slaunch.c | 598 +++++++++++++++
arch/x86/kernel/slmodule.c | 513 +++++++++++++
arch/x86/kernel/smpboot.c | 58 +-
arch/x86/realmode/init.c | 3 +
arch/x86/realmode/rm/header.S | 3 +
arch/x86/realmode/rm/trampoline_64.S | 32 +
drivers/char/tpm/tpm-chip.c | 24 +-
drivers/char/tpm/tpm-interface.c | 15 +
drivers/char/tpm/tpm-sysfs.c | 30 +
drivers/char/tpm/tpm.h | 1 +
drivers/char/tpm/tpm_tis_core.c | 25 +-
drivers/firmware/efi/libstub/x86-stub.c | 98 +++
drivers/iommu/intel/dmar.c | 4 +
include/crypto/sha1.h | 1 +
include/linux/slaunch.h | 542 +++++++++++++
include/linux/slr_table.h | 271 +++++++
include/linux/tpm.h | 10 +
kernel/kexec_core.c | 4 +
lib/crypto/sha1.c | 81 ++
42 files changed, 4946 insertions(+), 13 deletions(-)
create mode 100644 Documentation/security/launch-integrity/index.rst
create mode 100644 Documentation/security/launch-integrity/principles.rst
create mode 100644 Documentation/security/launch-integrity/secure_launch_details.rst
create mode 100644 Documentation/security/launch-integrity/secure_launch_overview.rst
create mode 100644 arch/x86/boot/compressed/early_sha1.c
create mode 100644 arch/x86/boot/compressed/early_sha256.c
create mode 100644 arch/x86/boot/compressed/kernel_info.h
create mode 100644 arch/x86/boot/compressed/sl_main.c
create mode 100644 arch/x86/boot/compressed/sl_stub.S
create mode 100644 arch/x86/kernel/slaunch.c
create mode 100644 arch/x86/kernel/slmodule.c
create mode 100644 include/linux/slaunch.h
create mode 100644 include/linux/slr_table.h

--
2.39.3

2024-05-31 01:32:54

by Ross Philipson

Subject: [PATCH v9 04/19] x86: Secure Launch Resource Table header file

Introduce the Secure Launch Resource Table which forms the formal
interface between the pre and post launch code.

Signed-off-by: Ross Philipson <[email protected]>
---
include/linux/slr_table.h | 271 ++++++++++++++++++++++++++++++++++++++
1 file changed, 271 insertions(+)
create mode 100644 include/linux/slr_table.h

diff --git a/include/linux/slr_table.h b/include/linux/slr_table.h
new file mode 100644
index 000000000000..213d8ac16f0f
--- /dev/null
+++ b/include/linux/slr_table.h
@@ -0,0 +1,271 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Secure Launch Resource Table
+ *
+ * Copyright (c) 2024, Oracle and/or its affiliates.
+ */
+
+#ifndef _LINUX_SLR_TABLE_H
+#define _LINUX_SLR_TABLE_H
+
+/* Put this in efi.h if it becomes a standard */
+#define SLR_TABLE_GUID EFI_GUID(0x877a9b2a, 0x0385, 0x45d1, 0xa0, 0x34, 0x9d, 0xac, 0x9c, 0x9e, 0x56, 0x5f)
+
+/* SLR table header values */
+#define SLR_TABLE_MAGIC 0x4452544d
+#define SLR_TABLE_REVISION 1
+
+/* Current revisions for the policy and UEFI config */
+#define SLR_POLICY_REVISION 1
+#define SLR_UEFI_CONFIG_REVISION 1
+
+/* SLR defined architectures */
+#define SLR_INTEL_TXT 1
+#define SLR_AMD_SKINIT 2
+
+/* SLR defined bootloaders */
+#define SLR_BOOTLOADER_INVALID 0
+#define SLR_BOOTLOADER_GRUB 1
+
+/* Log formats */
+#define SLR_DRTM_TPM12_LOG 1
+#define SLR_DRTM_TPM20_LOG 2
+
+/* DRTM Policy Entry Flags */
+#define SLR_POLICY_FLAG_MEASURED 0x1
+#define SLR_POLICY_IMPLICIT_SIZE 0x2
+
+/* Array Lengths */
+#define TPM_EVENT_INFO_LENGTH 32
+#define TXT_VARIABLE_MTRRS_LENGTH 32
+
+/* Tags */
+#define SLR_ENTRY_INVALID 0x0000
+#define SLR_ENTRY_DL_INFO 0x0001
+#define SLR_ENTRY_LOG_INFO 0x0002
+#define SLR_ENTRY_ENTRY_POLICY 0x0003
+#define SLR_ENTRY_INTEL_INFO 0x0004
+#define SLR_ENTRY_AMD_INFO 0x0005
+#define SLR_ENTRY_ARM_INFO 0x0006
+#define SLR_ENTRY_UEFI_INFO 0x0007
+#define SLR_ENTRY_UEFI_CONFIG 0x0008
+#define SLR_ENTRY_END 0xffff
+
+/* Entity Types */
+#define SLR_ET_UNSPECIFIED 0x0000
+#define SLR_ET_SLRT 0x0001
+#define SLR_ET_BOOT_PARAMS 0x0002
+#define SLR_ET_SETUP_DATA 0x0003
+#define SLR_ET_CMDLINE 0x0004
+#define SLR_ET_UEFI_MEMMAP 0x0005
+#define SLR_ET_RAMDISK 0x0006
+#define SLR_ET_TXT_OS2MLE 0x0010
+#define SLR_ET_UNUSED 0xffff
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Primary Secure Launch Resource Table Header
+ */
+struct slr_table {
+ u32 magic;
+ u16 revision;
+ u16 architecture;
+ u32 size;
+ u32 max_size;
+ /* table entries */
+} __packed;
+
+/*
+ * Common SLRT Table Header
+ */
+struct slr_entry_hdr {
+ u16 tag;
+ u16 size;
+} __packed;
+
+/*
+ * Boot loader context
+ */
+struct slr_bl_context {
+ u16 bootloader;
+ u16 reserved[3];
+ u64 context;
+} __packed;
+
+/*
+ * Dynamic Launch Callback Function type
+ */
+typedef void (*dl_handler_func)(struct slr_bl_context *bl_context);
+
+/*
+ * DRTM Dynamic Launch Configuration
+ */
+struct slr_entry_dl_info {
+ struct slr_entry_hdr hdr;
+ u32 dce_size;
+ u64 dce_base;
+ u64 dlme_size;
+ u64 dlme_base;
+ u64 dlme_entry;
+ struct slr_bl_context bl_context;
+ u64 dl_handler;
+} __packed;
+
+/*
+ * TPM Log Information
+ */
+struct slr_entry_log_info {
+ struct slr_entry_hdr hdr;
+ u16 format;
+ u16 reserved[3];
+ u32 size;
+ u64 addr;
+} __packed;
+
+/*
+ * DRTM Measurement Entry
+ */
+struct slr_policy_entry {
+ u16 pcr;
+ u16 entity_type;
+ u16 flags;
+ u16 reserved;
+ u64 size;
+ u64 entity;
+ char evt_info[TPM_EVENT_INFO_LENGTH];
+} __packed;
+
+/*
+ * DRTM Measurement Policy
+ */
+struct slr_entry_policy {
+ struct slr_entry_hdr hdr;
+ u16 revision;
+ u16 nr_entries;
+ struct slr_policy_entry policy_entries[];
+} __packed;
+
+/*
+ * Secure Launch defined MTRR saving structures
+ */
+struct slr_txt_mtrr_pair {
+ u64 mtrr_physbase;
+ u64 mtrr_physmask;
+} __packed;
+
+struct slr_txt_mtrr_state {
+ u64 default_mem_type;
+ u64 mtrr_vcnt;
+ struct slr_txt_mtrr_pair mtrr_pair[TXT_VARIABLE_MTRRS_LENGTH];
+} __packed;
+
+/*
+ * Intel TXT Info table
+ */
+struct slr_entry_intel_info {
+ struct slr_entry_hdr hdr;
+ u16 reserved[2];
+ u64 txt_heap;
+ u64 saved_misc_enable_msr;
+ struct slr_txt_mtrr_state saved_bsp_mtrrs;
+} __packed;
+
+/*
+ * UEFI config measurement entry
+ */
+struct slr_uefi_cfg_entry {
+ u16 pcr;
+ u16 reserved;
+ u32 size;
+ u64 cfg; /* address or value */
+ char evt_info[TPM_EVENT_INFO_LENGTH];
+} __packed;
+
+/*
+ * UEFI config measurements
+ */
+struct slr_entry_uefi_config {
+ struct slr_entry_hdr hdr;
+ u16 revision;
+ u16 nr_entries;
+ struct slr_uefi_cfg_entry uefi_cfg_entries[];
+} __packed;
+
+static inline void *slr_end_of_entries(struct slr_table *table)
+{
+ return (void *)table + table->size;
+}
+
+static inline void *
+slr_next_entry(struct slr_table *table,
+ struct slr_entry_hdr *curr)
+{
+ struct slr_entry_hdr *next = (struct slr_entry_hdr *)
+ ((u8 *)curr + curr->size);
+
+ if ((void *)next >= slr_end_of_entries(table))
+ return NULL;
+ if (next->tag == SLR_ENTRY_END)
+ return NULL;
+
+ return next;
+}
+
+static inline void *
+slr_next_entry_by_tag(struct slr_table *table,
+ struct slr_entry_hdr *entry,
+ u16 tag)
+{
+ if (!entry) /* Start from the beginning */
+ entry = (struct slr_entry_hdr *)(((u8 *)table) + sizeof(*table));
+
+ for ( ; ; ) {
+ if (entry->tag == tag)
+ return entry;
+
+ entry = slr_next_entry(table, entry);
+ if (!entry)
+ return NULL;
+ }
+
+ return NULL;
+}
+
+static inline int
+slr_add_entry(struct slr_table *table,
+ struct slr_entry_hdr *entry)
+{
+ struct slr_entry_hdr *end;
+
+ if ((table->size + entry->size) > table->max_size)
+ return -1;
+
+ memcpy((u8 *)table + table->size - sizeof(*end), entry, entry->size);
+ table->size += entry->size;
+
+ end = (struct slr_entry_hdr *)((u8 *)table + table->size - sizeof(*end));
+ end->tag = SLR_ENTRY_END;
+ end->size = sizeof(*end);
+
+ return 0;
+}
+
+static inline void
+slr_init_table(struct slr_table *slrt, u16 architecture, u32 max_size)
+{
+ struct slr_entry_hdr *end;
+
+ slrt->magic = SLR_TABLE_MAGIC;
+ slrt->revision = SLR_TABLE_REVISION;
+ slrt->architecture = architecture;
+ slrt->size = sizeof(*slrt) + sizeof(*end);
+ slrt->max_size = max_size;
+ end = (struct slr_entry_hdr *)((u8 *)slrt + sizeof(*slrt));
+ end->tag = SLR_ENTRY_END;
+ end->size = sizeof(*end);
+}
+
+#endif /* !__ASSEMBLY */
+
+#endif /* _LINUX_SLR_TABLE_H */
--
2.39.3

2024-05-31 01:33:15

by Ross Philipson

Subject: [PATCH v9 01/19] x86/boot: Place kernel_info at a fixed offset

From: Arvind Sankar <[email protected]>

There are use cases for storing the offset of a symbol in kernel_info.
For example, the trenchboot series [0] needs to store the offset of the
Measured Launch Environment header in kernel_info.

Since commit (note: commit ID from tip/master)

commit 527afc212231 ("x86/boot: Check that there are no run-time relocations")

run-time relocations are not allowed in the compressed kernel, so simply
using the symbol in kernel_info, as

.long symbol

will cause a linker error because this is not position-independent.

With kernel_info being a separate object file and in a different section
from startup_32, there is no way to calculate the offset of a symbol
from the start of the image in a position-independent way.

To enable such use cases, put kernel_info into its own section which is
placed at a predetermined offset (KERNEL_INFO_OFFSET) via the linker
script. This will allow calculating the symbol offset in a
position-independent way, by adding the offset from the start of
kernel_info to KERNEL_INFO_OFFSET.

Ensure that kernel_info is aligned, and use the SYM_DATA.* macros
instead of bare labels. This stores the size of the kernel_info
structure in the ELF symbol table.

Signed-off-by: Arvind Sankar <[email protected]>
Cc: Ross Philipson <[email protected]>
Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/boot/compressed/kernel_info.S | 19 +++++++++++++++----
arch/x86/boot/compressed/kernel_info.h | 12 ++++++++++++
arch/x86/boot/compressed/vmlinux.lds.S | 6 ++++++
3 files changed, 33 insertions(+), 4 deletions(-)
create mode 100644 arch/x86/boot/compressed/kernel_info.h

diff --git a/arch/x86/boot/compressed/kernel_info.S b/arch/x86/boot/compressed/kernel_info.S
index f818ee8fba38..c18f07181dd5 100644
--- a/arch/x86/boot/compressed/kernel_info.S
+++ b/arch/x86/boot/compressed/kernel_info.S
@@ -1,12 +1,23 @@
/* SPDX-License-Identifier: GPL-2.0 */

+#include <linux/linkage.h>
#include <asm/bootparam.h>
+#include "kernel_info.h"

- .section ".rodata.kernel_info", "a"
+/*
+ * If a field needs to hold the offset of a symbol from the start
+ * of the image, use the macro below, eg
+ * .long rva(symbol)
+ * This will avoid creating run-time relocations, which are not
+ * allowed in the compressed kernel.
+ */
+
+#define rva(X) (((X) - kernel_info) + KERNEL_INFO_OFFSET)

- .global kernel_info
+ .section ".rodata.kernel_info", "a"

-kernel_info:
+ .balign 16
+SYM_DATA_START(kernel_info)
/* Header, Linux top (structure). */
.ascii "LToP"
/* Size. */
@@ -19,4 +30,4 @@ kernel_info:

kernel_info_var_len_data:
/* Empty for time being... */
-kernel_info_end:
+SYM_DATA_END_LABEL(kernel_info, SYM_L_LOCAL, kernel_info_end)
diff --git a/arch/x86/boot/compressed/kernel_info.h b/arch/x86/boot/compressed/kernel_info.h
new file mode 100644
index 000000000000..c127f84aec63
--- /dev/null
+++ b/arch/x86/boot/compressed/kernel_info.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BOOT_COMPRESSED_KERNEL_INFO_H
+#define BOOT_COMPRESSED_KERNEL_INFO_H
+
+#ifdef CONFIG_X86_64
+#define KERNEL_INFO_OFFSET 0x500
+#else /* 32-bit */
+#define KERNEL_INFO_OFFSET 0x100
+#endif
+
+#endif /* BOOT_COMPRESSED_KERNEL_INFO_H */
diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S
index 083ec6d7722a..718c52f3f1e6 100644
--- a/arch/x86/boot/compressed/vmlinux.lds.S
+++ b/arch/x86/boot/compressed/vmlinux.lds.S
@@ -7,6 +7,7 @@ OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT)

#include <asm/cache.h>
#include <asm/page_types.h>
+#include "kernel_info.h"

#ifdef CONFIG_X86_64
OUTPUT_ARCH(i386:x86-64)
@@ -27,6 +28,11 @@ SECTIONS
HEAD_TEXT
_ehead = . ;
}
+ .rodata.kernel_info KERNEL_INFO_OFFSET : {
+ *(.rodata.kernel_info)
+ }
+ ASSERT(ABSOLUTE(kernel_info) == KERNEL_INFO_OFFSET, "kernel_info at bad address!")
+
.rodata..compressed : {
*(.rodata..compressed)
}
--
2.39.3

2024-05-31 01:34:11

by Ross Philipson

Subject: [PATCH v9 08/19] x86: Secure Launch kernel early boot stub

The Secure Launch (SL) stub provides the entry point for Intel TXT (and
later AMD SKINIT) to vector to during the late launch. The symbol
sl_stub_entry is that entry point and its offset into the kernel is
conveyed to the launching code using the MLE (Measured Launch
Environment) header in the structure named mle_header. The offset of the
MLE header is set in the kernel_info. The routine sl_stub contains the
very early late launch setup code responsible for setting up the basic
environment to allow the normal kernel startup_32 code to proceed. It is
also responsible for properly waking and handling the APs on Intel
platforms. The routine sl_main which runs after entering 64b mode is
responsible for measuring configuration and module information before
it is used like the boot params, the kernel command line, the TXT heap,
an external initramfs, etc.

Signed-off-by: Ross Philipson <[email protected]>
---
Documentation/arch/x86/boot.rst | 21 +
arch/x86/boot/compressed/Makefile | 3 +-
arch/x86/boot/compressed/head_64.S | 30 +
arch/x86/boot/compressed/kernel_info.S | 34 ++
arch/x86/boot/compressed/sl_main.c | 577 ++++++++++++++++++++
arch/x86/boot/compressed/sl_stub.S | 725 +++++++++++++++++++++++++
arch/x86/include/asm/msr-index.h | 5 +
arch/x86/include/uapi/asm/bootparam.h | 1 +
arch/x86/kernel/asm-offsets.c | 20 +
9 files changed, 1415 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/boot/compressed/sl_main.c
create mode 100644 arch/x86/boot/compressed/sl_stub.S

diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst
index 4fd492cb4970..295cdf9bcbdb 100644
--- a/Documentation/arch/x86/boot.rst
+++ b/Documentation/arch/x86/boot.rst
@@ -482,6 +482,14 @@ Protocol: 2.00+
- If 1, KASLR enabled.
- If 0, KASLR disabled.

+ Bit 2 (kernel internal): SLAUNCH_FLAG
+
+ - Used internally by the setup kernel to communicate
+ Secure Launch status to kernel proper.
+
+ - If 1, Secure Launch enabled.
+ - If 0, Secure Launch disabled.
+
Bit 5 (write): QUIET_FLAG

- If 0, print early messages.
@@ -1028,6 +1036,19 @@ Offset/size: 0x000c/4

This field contains maximal allowed type for setup_data and setup_indirect structs.

+============ =================
+Field name: mle_header_offset
+Offset/size: 0x0010/4
+============ =================
+
+ This field contains the offset to the Secure Launch Measured Launch Environment
+ (MLE) header. This offset is used to locate information needed during a secure
+ late launch using Intel TXT. If the offset is zero, the kernel does not have
+ Secure Launch capabilities. The MLE entry point is called from TXT on the BSP
+ following a success measured launch. The specific state of the processors is
+ outlined in the TXT Software Development Guide, the latest can be found here:
+ https://www.intel.com/content/dam/www/public/us/en/documents/guides/intel-txt-software-development-guide.pdf
+

The Image Checksum
==================
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 9189a0e28686..9076a248d4b4 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -118,7 +118,8 @@ vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_mixed.o
vmlinux-objs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a

-vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o
+vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o \
+ $(obj)/sl_main.o $(obj)/sl_stub.o

$(obj)/vmlinux: $(vmlinux-objs-y) FORCE
$(call if_changed,ld)
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index 1dcb794c5479..803c9e2e6d85 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -420,6 +420,13 @@ SYM_CODE_START(startup_64)
pushq $0
popfq

+#ifdef CONFIG_SECURE_LAUNCH
+ /* Ensure the relocation region is coverd by a PMR */
+ movq %rbx, %rdi
+ movl $(_bss - startup_32), %esi
+ callq sl_check_region
+#endif
+
/*
* Copy the compressed kernel to the end of our buffer
* where decompression in place becomes safe.
@@ -462,6 +469,29 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
shrq $3, %rcx
rep stosq

+#ifdef CONFIG_SECURE_LAUNCH
+ /*
+ * Have to do the final early sl stub work in 64b area.
+ *
+ * *********** NOTE ***********
+ *
+ * Several boot params get used before we get a chance to measure
+ * them in this call. This is a known issue and we currently don't
+ * have a solution. The scratch field doesn't matter. There is no
+ * obvious way to do anything about the use of kernel_alignment or
+ * init_size though these seem low risk with all the PMR and overlap
+ * checks in place.
+ */
+ movq %r15, %rdi
+ callq sl_main
+
+ /* Ensure the decompression location is covered by a PMR */
+ movq %rbp, %rdi
+ movq output_len(%rip), %rsi
+ callq sl_check_region
+#endif
+
+ pushq %rsi
call load_stage2_idt

/* Pass boot_params to initialize_identity_maps() */
diff --git a/arch/x86/boot/compressed/kernel_info.S b/arch/x86/boot/compressed/kernel_info.S
index c18f07181dd5..e199b87764e9 100644
--- a/arch/x86/boot/compressed/kernel_info.S
+++ b/arch/x86/boot/compressed/kernel_info.S
@@ -28,6 +28,40 @@ SYM_DATA_START(kernel_info)
/* Maximal allowed type for setup_data and setup_indirect structs. */
.long SETUP_TYPE_MAX

+ /* Offset to the MLE header structure */
+#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
+ .long rva(mle_header)
+#else
+ .long 0
+#endif
+
kernel_info_var_len_data:
/* Empty for time being... */
SYM_DATA_END_LABEL(kernel_info, SYM_L_LOCAL, kernel_info_end)
+
+#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
+ /*
+ * The MLE Header per the TXT Specification, section 2.1
+ * MLE capabilities, see table 4. Capabilities set:
+ * bit 0: Support for GETSEC[WAKEUP] for RLP wakeup
+ * bit 1: Support for RLP wakeup using MONITOR address
+ * bit 2: The ECX register will contain the pointer to the MLE page table
+ * bit 5: TPM 1.2 family: Details/authorities PCR usage support
+ * bit 9: Supported format of TPM 2.0 event log - TCG compliant
+ */
+SYM_DATA_START(mle_header)
+ .long 0x9082ac5a /* UUID0 */
+ .long 0x74a7476f /* UUID1 */
+ .long 0xa2555c0f /* UUID2 */
+ .long 0x42b651cb /* UUID3 */
+ .long 0x00000034 /* MLE header size */
+ .long 0x00020002 /* MLE version 2.2 */
+ .long rva(sl_stub_entry) /* Linear entry point of MLE (virt. address) */
+ .long 0x00000000 /* First valid page of MLE */
+ .long 0x00000000 /* Offset within binary of first byte of MLE */
+ .long rva(_edata) /* Offset within binary of last byte + 1 of MLE */
+ .long 0x00000227 /* Bit vector of MLE-supported capabilities */
+ .long 0x00000000 /* Starting linear address of command line (unused) */
+ .long 0x00000000 /* Ending linear address of command line (unused) */
+SYM_DATA_END(mle_header)
+#endif
diff --git a/arch/x86/boot/compressed/sl_main.c b/arch/x86/boot/compressed/sl_main.c
new file mode 100644
index 000000000000..61e9baf410fd
--- /dev/null
+++ b/arch/x86/boot/compressed/sl_main.c
@@ -0,0 +1,577 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Secure Launch early measurement and validation routines.
+ *
+ * Copyright (c) 2024, Oracle and/or its affiliates.
+ */
+
+#include <linux/init.h>
+#include <linux/string.h>
+#include <linux/linkage.h>
+#include <asm/segment.h>
+#include <asm/boot.h>
+#include <asm/msr.h>
+#include <asm/mtrr.h>
+#include <asm/processor-flags.h>
+#include <asm/asm-offsets.h>
+#include <asm/bootparam.h>
+#include <asm/bootparam_utils.h>
+#include <linux/slr_table.h>
+#include <linux/slaunch.h>
+#include <crypto/sha1.h>
+#include <crypto/sha2.h>
+
+#define CAPS_VARIABLE_MTRR_COUNT_MASK 0xff
+
+#define SL_TPM12_LOG 1
+#define SL_TPM20_LOG 2
+
+#define SL_TPM20_MAX_ALGS 2
+
+#define SL_MAX_EVENT_DATA 64
+#define SL_TPM12_LOG_SIZE (sizeof(struct tcg_pcr_event) + \
+ SL_MAX_EVENT_DATA)
+#define SL_TPM20_LOG_SIZE (sizeof(struct tcg_pcr_event2_head) + \
+ SHA1_DIGEST_SIZE + SHA256_DIGEST_SIZE + \
+ sizeof(struct tcg_event_field) + \
+ SL_MAX_EVENT_DATA)
+
+static void *evtlog_base;
+static u32 evtlog_size;
+static struct txt_heap_event_log_pointer2_1_element *log20_elem;
+static u32 tpm_log_ver = SL_TPM12_LOG;
+static struct tcg_efi_specid_event_algs tpm_algs[SL_TPM20_MAX_ALGS] = {0};
+
+extern u32 sl_cpu_type;
+extern u32 sl_mle_start;
+
+static u64 sl_txt_read(u32 reg)
+{
+ return readq((void *)(u64)(TXT_PRIV_CONFIG_REGS_BASE + reg));
+}
+
+static void sl_txt_write(u32 reg, u64 val)
+{
+ writeq(val, (void *)(u64)(TXT_PRIV_CONFIG_REGS_BASE + reg));
+}
+
+static void __noreturn sl_txt_reset(u64 error)
+{
+ /* Reading the E2STS register acts as a barrier for TXT registers */
+ sl_txt_write(TXT_CR_ERRORCODE, error);
+ sl_txt_read(TXT_CR_E2STS);
+ sl_txt_write(TXT_CR_CMD_UNLOCK_MEM_CONFIG, 1);
+ sl_txt_read(TXT_CR_E2STS);
+ sl_txt_write(TXT_CR_CMD_RESET, 1);
+
+ for ( ; ; )
+ asm volatile ("hlt");
+
+ unreachable();
+}
+
+static u64 sl_rdmsr(u32 reg)
+{
+ u64 lo, hi;
+
+ asm volatile ("rdmsr" : "=a" (lo), "=d" (hi) : "c" (reg));
+
+ return (hi << 32) | lo;
+}
+
+static struct slr_table *sl_locate_and_validate_slrt(void)
+{
+ struct txt_os_mle_data *os_mle_data;
+ struct slr_table *slrt;
+ void *txt_heap;
+
+ txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
+ os_mle_data = txt_os_mle_data_start(txt_heap);
+
+ if (!os_mle_data->slrt)
+ sl_txt_reset(SL_ERROR_INVALID_SLRT);
+
+ slrt = (struct slr_table *)os_mle_data->slrt;
+
+ if (slrt->magic != SLR_TABLE_MAGIC)
+ sl_txt_reset(SL_ERROR_INVALID_SLRT);
+
+ if (slrt->architecture != SLR_INTEL_TXT)
+ sl_txt_reset(SL_ERROR_INVALID_SLRT);
+
+ return slrt;
+}
+
+static void sl_check_pmr_coverage(void *base, u32 size, bool allow_hi)
+{
+ struct txt_os_sinit_data *os_sinit_data;
+ void *end = base + size;
+ void *txt_heap;
+
+ if (!(sl_cpu_type & SL_CPU_INTEL))
+ return;
+
+ txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
+ os_sinit_data = txt_os_sinit_data_start(txt_heap);
+
+ if ((end >= (void *)0x100000000ULL) && (base < (void *)0x100000000ULL))
+ sl_txt_reset(SL_ERROR_REGION_STRADDLE_4GB);
+
+ /*
+ * Note that the late stub code validates that the hi PMR covers
+ * all memory above 4G. At this point the code can only check that
+ * regions are within the hi PMR but that is sufficient.
+ */
+ if ((end > (void *)0x100000000ULL) && (base >= (void *)0x100000000ULL)) {
+ if (allow_hi) {
+ if (end >= (void *)(os_sinit_data->vtd_pmr_hi_base +
+ os_sinit_data->vtd_pmr_hi_size))
+ sl_txt_reset(SL_ERROR_BUFFER_BEYOND_PMR);
+ } else {
+ sl_txt_reset(SL_ERROR_REGION_ABOVE_4GB);
+ }
+ }
+
+ if (end >= (void *)os_sinit_data->vtd_pmr_lo_size)
+ sl_txt_reset(SL_ERROR_BUFFER_BEYOND_PMR);
+}
+
+/*
+ * Some MSRs are modified by the pre-launch code including the MTRRs.
+ * The early MLE code has to restore these values. This code validates
+ * the values after they are measured.
+ */
+static void sl_txt_validate_msrs(struct txt_os_mle_data *os_mle_data)
+{
+ struct slr_txt_mtrr_state *saved_bsp_mtrrs;
+ u64 mtrr_caps, mtrr_def_type, mtrr_var;
+ struct slr_entry_intel_info *txt_info;
+ u64 misc_en_msr;
+ u32 vcnt, i;
+
+ txt_info = (struct slr_entry_intel_info *)os_mle_data->txt_info;
+ saved_bsp_mtrrs = &txt_info->saved_bsp_mtrrs;
+
+ mtrr_caps = sl_rdmsr(MSR_MTRRcap);
+ vcnt = (u32)(mtrr_caps & CAPS_VARIABLE_MTRR_COUNT_MASK);
+
+ if (saved_bsp_mtrrs->mtrr_vcnt > vcnt)
+ sl_txt_reset(SL_ERROR_MTRR_INV_VCNT);
+ if (saved_bsp_mtrrs->mtrr_vcnt > TXT_OS_MLE_MAX_VARIABLE_MTRRS)
+ sl_txt_reset(SL_ERROR_MTRR_INV_VCNT);
+
+ mtrr_def_type = sl_rdmsr(MSR_MTRRdefType);
+ if (saved_bsp_mtrrs->default_mem_type != mtrr_def_type)
+ sl_txt_reset(SL_ERROR_MTRR_INV_DEF_TYPE);
+
+ for (i = 0; i < saved_bsp_mtrrs->mtrr_vcnt; i++) {
+ mtrr_var = sl_rdmsr(MTRRphysBase_MSR(i));
+ if (saved_bsp_mtrrs->mtrr_pair[i].mtrr_physbase != mtrr_var)
+ sl_txt_reset(SL_ERROR_MTRR_INV_BASE);
+ mtrr_var = sl_rdmsr(MTRRphysMask_MSR(i));
+ if (saved_bsp_mtrrs->mtrr_pair[i].mtrr_physmask != mtrr_var)
+ sl_txt_reset(SL_ERROR_MTRR_INV_MASK);
+ }
+
+ misc_en_msr = sl_rdmsr(MSR_IA32_MISC_ENABLE);
+ if (txt_info->saved_misc_enable_msr != misc_en_msr)
+ sl_txt_reset(SL_ERROR_MSR_INV_MISC_EN);
+}
+
+static void sl_find_drtm_event_log(struct slr_table *slrt)
+{
+ struct txt_os_sinit_data *os_sinit_data;
+ struct slr_entry_log_info *log_info;
+ void *txt_heap;
+
+ log_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_LOG_INFO);
+ if (!log_info)
+ sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
+
+ evtlog_base = (void *)log_info->addr;
+ evtlog_size = log_info->size;
+
+ txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
+
+ /*
+ * For TPM 2.0, the event log 2.1 extended data structure has to also
+ * be located and fixed up.
+ */
+ os_sinit_data = txt_os_sinit_data_start(txt_heap);
+
+ /*
+ * Only support version 6 and later that properly handle the
+ * list of ExtDataElements in the OS-SINIT structure.
+ */
+ if (os_sinit_data->version < 6)
+ sl_txt_reset(SL_ERROR_OS_SINIT_BAD_VERSION);
+
+ /* Find the TPM2.0 logging extended heap element */
+ log20_elem = tpm20_find_log2_1_element(os_sinit_data);
+
+ /* If found, this implies TPM20 log and family */
+ if (log20_elem)
+ tpm_log_ver = SL_TPM20_LOG;
+}
+
+static void sl_validate_event_log_buffer(void)
+{
+ struct txt_os_sinit_data *os_sinit_data;
+ void *txt_heap, *txt_end;
+ void *mle_base, *mle_end;
+ void *evtlog_end;
+
+ if ((u64)evtlog_size > (LLONG_MAX - (u64)evtlog_base))
+ sl_txt_reset(SL_ERROR_INTEGER_OVERFLOW);
+ evtlog_end = evtlog_base + evtlog_size;
+
+ txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
+ txt_end = txt_heap + sl_txt_read(TXT_CR_HEAP_SIZE);
+ os_sinit_data = txt_os_sinit_data_start(txt_heap);
+
+ mle_base = (void *)(u64)sl_mle_start;
+ mle_end = mle_base + os_sinit_data->mle_size;
+
+ /*
+ * This check is to ensure the event log buffer does not overlap with
+ * the MLE image.
+ */
+ if (evtlog_base >= mle_end && evtlog_end > mle_end)
+ goto pmr_check; /* above */
+
+ if (evtlog_end <= mle_base && evtlog_base < mle_base)
+ goto pmr_check; /* below */
+
+ sl_txt_reset(SL_ERROR_MLE_BUFFER_OVERLAP);
+
+pmr_check:
+ /*
+ * The TXT heap is protected by the DPR. If the TPM event log is
+ * inside the TXT heap, there is no need for a PMR check.
+ */
+ if (evtlog_base > txt_heap && evtlog_end < txt_end)
+ return;
+
+ sl_check_pmr_coverage(evtlog_base, evtlog_size, true);
+}
+
+static void sl_find_event_log_algorithms(void)
+{
+ struct tcg_efi_specid_event_head *efi_head =
+ (struct tcg_efi_specid_event_head *)(evtlog_base +
+ log20_elem->first_record_offset +
+ sizeof(struct tcg_pcr_event));
+
+ if (efi_head->num_algs == 0 || efi_head->num_algs > 2)
+ sl_txt_reset(SL_ERROR_TPM_NUMBER_ALGS);
+
+ memcpy(&tpm_algs[0], &efi_head->digest_sizes[0],
+ sizeof(struct tcg_efi_specid_event_algs) * efi_head->num_algs);
+}
+
+static void sl_tpm12_log_event(u32 pcr, u32 event_type,
+ const u8 *data, u32 length,
+ const u8 *event_data, u32 event_size)
+{
+ u8 sha1_hash[SHA1_DIGEST_SIZE] = {0};
+ u8 log_buf[SL_TPM12_LOG_SIZE] = {0};
+ struct tcg_pcr_event *pcr_event;
+ u32 total_size;
+
+ pcr_event = (struct tcg_pcr_event *)log_buf;
+ pcr_event->pcr_idx = pcr;
+ pcr_event->event_type = event_type;
+ if (length > 0) {
+ sha1(data, length, &sha1_hash[0]);
+ memcpy(&pcr_event->digest[0], &sha1_hash[0], SHA1_DIGEST_SIZE);
+ }
+ pcr_event->event_size = event_size;
+ if (event_size > 0)
+ memcpy((u8 *)pcr_event + sizeof(struct tcg_pcr_event),
+ event_data, event_size);
+
+ total_size = sizeof(struct tcg_pcr_event) + event_size;
+
+ if (tpm12_log_event(evtlog_base, evtlog_size, total_size, pcr_event))
+ sl_txt_reset(SL_ERROR_TPM_LOGGING_FAILED);
+}
+
+static void sl_tpm20_log_event(u32 pcr, u32 event_type,
+ const u8 *data, u32 length,
+ const u8 *event_data, u32 event_size)
+{
+ u8 sha256_hash[SHA256_DIGEST_SIZE] = {0};
+ u8 sha1_hash[SHA1_DIGEST_SIZE] = {0};
+ u8 log_buf[SL_TPM20_LOG_SIZE] = {0};
+ struct sha256_state sctx256 = {0};
+ struct tcg_pcr_event2_head *head;
+ struct tcg_event_field *event;
+ u32 total_size;
+ u16 *alg_ptr;
+ u8 *dgst_ptr;
+
+ head = (struct tcg_pcr_event2_head *)log_buf;
+ head->pcr_idx = pcr;
+ head->event_type = event_type;
+ total_size = sizeof(struct tcg_pcr_event2_head);
+ alg_ptr = (u16 *)(log_buf + sizeof(struct tcg_pcr_event2_head));
+
+ for ( ; head->count < 2; head->count++) {
+ if (!tpm_algs[head->count].alg_id)
+ break;
+
+ *alg_ptr = tpm_algs[head->count].alg_id;
+ dgst_ptr = (u8 *)alg_ptr + sizeof(u16);
+
+ if (tpm_algs[head->count].alg_id == TPM_ALG_SHA256 &&
+ length) {
+ sha256_init(&sctx256);
+ sha256_update(&sctx256, data, length);
+ sha256_final(&sctx256, &sha256_hash[0]);
+ } else if (tpm_algs[head->count].alg_id == TPM_ALG_SHA1 &&
+ length) {
+ sha1(data, length, &sha1_hash[0]);
+ }
+
+ if (tpm_algs[head->count].alg_id == TPM_ALG_SHA256) {
+ memcpy(dgst_ptr, &sha256_hash[0], SHA256_DIGEST_SIZE);
+ total_size += SHA256_DIGEST_SIZE + sizeof(u16);
+ alg_ptr = (u16 *)((u8 *)alg_ptr + SHA256_DIGEST_SIZE + sizeof(u16));
+ } else if (tpm_algs[head->count].alg_id == TPM_ALG_SHA1) {
+ memcpy(dgst_ptr, &sha1_hash[0], SHA1_DIGEST_SIZE);
+ total_size += SHA1_DIGEST_SIZE + sizeof(u16);
+ alg_ptr = (u16 *)((u8 *)alg_ptr + SHA1_DIGEST_SIZE + sizeof(u16));
+ } else {
+ sl_txt_reset(SL_ERROR_TPM_UNKNOWN_DIGEST);
+ }
+ }
+
+ event = (struct tcg_event_field *)(log_buf + total_size);
+ event->event_size = event_size;
+ if (event_size > 0)
+ memcpy((u8 *)event + sizeof(struct tcg_event_field), event_data, event_size);
+ total_size += sizeof(struct tcg_event_field) + event_size;
+
+ if (tpm20_log_event(log20_elem, evtlog_base, evtlog_size, total_size, &log_buf[0]))
+ sl_txt_reset(SL_ERROR_TPM_LOGGING_FAILED);
+}
+
+static void sl_tpm_extend_evtlog(u32 pcr, u32 type,
+ const u8 *data, u32 length, const char *desc)
+{
+ if (tpm_log_ver == SL_TPM20_LOG)
+ sl_tpm20_log_event(pcr, type, data, length,
+ (const u8 *)desc, strlen(desc));
+ else
+ sl_tpm12_log_event(pcr, type, data, length,
+ (const u8 *)desc, strlen(desc));
+}
+
+static struct setup_data *sl_handle_setup_data(struct setup_data *curr,
+ struct slr_policy_entry *entry)
+{
+ struct setup_indirect *ind;
+ struct setup_data *next;
+
+ if (!curr)
+ return NULL;
+
+ next = (struct setup_data *)(unsigned long)curr->next;
+
+ /* SETUP_INDIRECT instances have to be handled differently */
+ if (curr->type == SETUP_INDIRECT) {
+ ind = (struct setup_indirect *)((u8 *)curr + offsetof(struct setup_data, data));
+
+ sl_check_pmr_coverage((void *)ind->addr, ind->len, true);
+
+ sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
+ (void *)ind->addr, ind->len,
+ entry->evt_info);
+
+ return next;
+ }
+
+ sl_check_pmr_coverage(((u8 *)curr) + sizeof(struct setup_data),
+ curr->len, true);
+
+ sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
+ ((u8 *)curr) + sizeof(struct setup_data),
+ curr->len,
+ entry->evt_info);
+
+ return next;
+}
+
+static void sl_extend_setup_data(struct slr_policy_entry *entry)
+{
+ struct setup_data *data;
+
+ /*
+ * Measuring the boot params measured the fixed e820 memory map.
+ * Measure any setup_data entries including e820 extended entries.
+ */
+ data = (struct setup_data *)(unsigned long)entry->entity;
+ while (data)
+ data = sl_handle_setup_data(data, entry);
+}
+
+static void sl_extend_slrt(struct slr_policy_entry *entry)
+{
+ struct slr_table *slrt = (struct slr_table *)entry->entity;
+ struct slr_entry_intel_info *intel_info;
+
+ /*
+ * In revision one of the SLRT, the only table that needs to be
+ * measured is the Intel info table. Everything else is meta-data,
+ * addresses and sizes. Note the size of what to measure is not set.
+ * The flag SLR_POLICY_IMPLICIT_SIZE leaves it to the measuring code
+ * to sort out.
+ */
+ if (slrt->revision == 1) {
+ intel_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_INTEL_INFO);
+ if (!intel_info)
+ sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
+
+ sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
+ (void *)entry->entity, sizeof(struct slr_entry_intel_info),
+ entry->evt_info);
+ }
+}
+
+static void sl_extend_txt_os2mle(struct slr_policy_entry *entry)
+{
+ struct txt_os_mle_data *os_mle_data;
+ void *txt_heap;
+
+ txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
+ os_mle_data = txt_os_mle_data_start(txt_heap);
+
+ /*
+ * Version 1 of the OS-MLE heap structure has no fields to measure. It just
+ * has addresses and sizes and a scratch buffer.
+ */
+ if (os_mle_data->version == 1)
+ return;
+}
+
+static void sl_process_extend_policy(struct slr_table *slrt)
+{
+ struct slr_entry_policy *policy;
+ u16 i;
+
+ policy = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_ENTRY_POLICY);
+ if (!policy)
+ sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
+
+ for (i = 0; i < policy->nr_entries; i++) {
+ switch (policy->policy_entries[i].entity_type) {
+ case SLR_ET_SETUP_DATA:
+ sl_extend_setup_data(&policy->policy_entries[i]);
+ break;
+ case SLR_ET_SLRT:
+ sl_extend_slrt(&policy->policy_entries[i]);
+ break;
+ case SLR_ET_TXT_OS2MLE:
+ sl_extend_txt_os2mle(&policy->policy_entries[i]);
+ break;
+ case SLR_ET_UNUSED:
+ continue;
+ default:
+ sl_tpm_extend_evtlog(policy->policy_entries[i].pcr, TXT_EVTYPE_SLAUNCH,
+ (void *)policy->policy_entries[i].entity,
+ policy->policy_entries[i].size,
+ policy->policy_entries[i].evt_info);
+ }
+ }
+}
+
+static void sl_process_extend_uefi_config(struct slr_table *slrt)
+{
+ struct slr_entry_uefi_config *uefi_config;
+ u16 i;
+
+ uefi_config = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_UEFI_CONFIG);
+
+ /* Optionally here depending on how SL kernel was booted */
+ if (!uefi_config)
+ return;
+
+ for (i = 0; i < uefi_config->nr_entries; i++) {
+ sl_tpm_extend_evtlog(uefi_config->uefi_cfg_entries[i].pcr, TXT_EVTYPE_SLAUNCH,
+ (void *)uefi_config->uefi_cfg_entries[i].cfg,
+ uefi_config->uefi_cfg_entries[i].size,
+ uefi_config->uefi_cfg_entries[i].evt_info);
+ }
+}
+
+asmlinkage __visible void sl_check_region(void *base, u32 size)
+{
+ sl_check_pmr_coverage(base, size, false);
+}
+
+asmlinkage __visible void sl_main(void *bootparams)
+{
+ struct boot_params *bp = (struct boot_params *)bootparams;
+ struct txt_os_mle_data *os_mle_data;
+ struct slr_table *slrt;
+ void *txt_heap;
+
+ /*
+ * Ensure loadflags do not indicate a secure launch was done
+ * unless it really was.
+ */
+ bp->hdr.loadflags &= ~SLAUNCH_FLAG;
+
+ /*
+ * Currently only Intel TXT is supported for Secure Launch. Testing
+ * this value also indicates that the kernel was booted successfully
+ * through the Secure Launch entry point and is in SMX mode.
+ */
+ if (!(sl_cpu_type & SL_CPU_INTEL))
+ return;
+
+ slrt = sl_locate_and_validate_slrt();
+
+ /* Locate the TPM event log. */
+ sl_find_drtm_event_log(slrt);
+
+ /* Validate the location of the event log buffer before using it */
+ sl_validate_event_log_buffer();
+
+ /*
+ * Find the TPM hash algorithms used by the ACM and recorded in the
+ * event log.
+ */
+ if (tpm_log_ver == SL_TPM20_LOG)
+ sl_find_event_log_algorithms();
+
+ /*
+ * Sanitize them before measuring. Set the SLAUNCH_FLAG early since if
+ * anything fails, the system will reset anyway.
+ */
+ sanitize_boot_params(bp);
+ bp->hdr.loadflags |= SLAUNCH_FLAG;
+
+ sl_check_pmr_coverage(bootparams, PAGE_SIZE, false);
+
+ /* Place event log SL specific tags before and after measurements */
+ sl_tpm_extend_evtlog(17, TXT_EVTYPE_SLAUNCH_START, NULL, 0, "");
+
+ /* Process all policy entries and extend the measurements to the evtlog */
+ sl_process_extend_policy(slrt);
+
+ /* Process all EFI config entries and extend the measurements to the evtlog */
+ sl_process_extend_uefi_config(slrt);
+
+ sl_tpm_extend_evtlog(17, TXT_EVTYPE_SLAUNCH_END, NULL, 0, "");
+
+ /* No PMR check is needed, the TXT heap is covered by the DPR */
+ txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
+ os_mle_data = txt_os_mle_data_start(txt_heap);
+
+ /*
+ * Now that the OS-MLE data is measured, ensure the MTRR and
+ * misc enable MSRs are what we expect.
+ */
+ sl_txt_validate_msrs(os_mle_data);
+}
diff --git a/arch/x86/boot/compressed/sl_stub.S b/arch/x86/boot/compressed/sl_stub.S
new file mode 100644
index 000000000000..24b8f23d5dcc
--- /dev/null
+++ b/arch/x86/boot/compressed/sl_stub.S
@@ -0,0 +1,725 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Secure Launch protected mode entry point.
+ *
+ * Copyright (c) 2024, Oracle and/or its affiliates.
+ */
+ .code32
+ .text
+#include <linux/linkage.h>
+#include <asm/segment.h>
+#include <asm/msr.h>
+#include <asm/apicdef.h>
+#include <asm/trapnr.h>
+#include <asm/processor-flags.h>
+#include <asm/asm-offsets.h>
+#include <asm/bootparam.h>
+#include <asm/page_types.h>
+#include <asm/irq_vectors.h>
+#include <linux/slr_table.h>
+#include <linux/slaunch.h>
+
+/* CPUID: leaf 1, ECX, SMX feature bit */
+#define X86_FEATURE_BIT_SMX (1 << 6)
+
+#define IDT_VECTOR_LO_BITS 0
+#define IDT_VECTOR_HI_BITS 6
+
+/*
+ * See the comment in head_64.S for detailed information on what this macro
+ * and others like it are used for. The comment appears right at the top of
+ * the file.
+ */
+#define rva(X) ((X) - sl_stub_entry)
+
+/*
+ * The GETSEC op code is open coded because older versions of
+ * GCC do not support the getsec mnemonic.
+ */
+.macro GETSEC leaf
+ pushl %ebx
+ xorl %ebx, %ebx /* Must be zero for SMCTRL */
+ movl \leaf, %eax /* Leaf function */
+ .byte 0x0f, 0x37 /* GETSEC opcode */
+ popl %ebx
+.endm
+
+.macro TXT_RESET error
+ /*
+ * Set a sticky error value and reset. Note the movs to %eax act as
+ * TXT register barriers.
+ */
+ movl \error, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ERRORCODE)
+ movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
+ movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_NO_SECRETS)
+ movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
+ movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_UNLOCK_MEM_CONFIG)
+ movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
+ movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_RESET)
+1:
+ hlt
+ jmp 1b
+.endm
+
+ .code32
+SYM_FUNC_START(sl_stub_entry)
+ cli
+ cld
+
+ /*
+ * On entry, %ebx has the entry abs offset to sl_stub_entry. This
+ * will be correctly scaled using the rva macro and avoid causing
+ * relocations. Only %cs and %ds segments are known good.
+ */
+
+ /* Load GDT, set segment regs and lret to __SL32_CS */
+ leal rva(sl_gdt_desc)(%ebx), %eax
+ addl %eax, 2(%eax)
+ lgdt (%eax)
+
+ movl $(__SL32_DS), %eax
+ movw %ax, %ds
+ movw %ax, %es
+ movw %ax, %fs
+ movw %ax, %gs
+ movw %ax, %ss
+
+ /*
+ * Now that %ss is known good, take the first stack for the BSP. The
+ * AP stacks are only used on Intel.
+ */
+ leal rva(sl_stacks_end)(%ebx), %esp
+
+ leal rva(.Lsl_cs)(%ebx), %eax
+ pushl $(__SL32_CS)
+ pushl %eax
+ lret
+
+.Lsl_cs:
+ /* Save our base pointer reg and page table for MLE */
+ pushl %ebx
+ pushl %ecx
+
+ /* See if SMX feature is supported. */
+ movl $1, %eax
+ cpuid
+ testl $(X86_FEATURE_BIT_SMX), %ecx
+ jz .Ldo_unknown_cpu
+
+ popl %ecx
+ popl %ebx
+
+ /* Know it is Intel */
+ movl $(SL_CPU_INTEL), rva(sl_cpu_type)(%ebx)
+
+ /* Locate the base of the MLE using the page tables in %ecx */
+ call sl_find_mle_base
+
+ /* Increment CPU count for BSP */
+ incl rva(sl_txt_cpu_count)(%ebx)
+
+ /*
+ * Enable SMI with GETSEC[SMCTRL] which were disabled by SENTER.
+ * NMIs were also disabled by SENTER. Since there is no IDT for the BSP,
+ * allow the mainline kernel re-enable them in the normal course of
+ * booting.
+ */
+ GETSEC $(SMX_X86_GETSEC_SMCTRL)
+
+ /* Clear the TXT error registers for a clean start of day */
+ movl $0, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ERRORCODE)
+ movl $0xffffffff, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ESTS)
+
+ /* On Intel, the zero page address is passed in the TXT heap */
+ /* Read physical base of heap into EAX */
+ movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
+ /* Read the size of the BIOS data into ECX (first 8 bytes) */
+ movl (%eax), %ecx
+ /* Skip over BIOS data and size of OS to MLE data section */
+ leal 8(%eax, %ecx), %eax
+
+ /* Need to verify the values in the OS-MLE struct passed in */
+ call sl_txt_verify_os_mle_struct
+
+ /*
+ * Get the boot params address from the heap. Note %esi and %ebx MUST
+ * be preserved across calls and operations.
+ */
+ movl SL_boot_params_addr(%eax), %esi
+
+ /* Save %ebx so the APs can find their way home */
+ movl %ebx, (SL_mle_scratch + SL_SCRATCH_AP_EBX)(%eax)
+
+ /* Fetch the AP wake code block address from the heap */
+ movl SL_ap_wake_block(%eax), %edi
+ movl %edi, rva(sl_txt_ap_wake_block)(%ebx)
+
+ /* Store the offset in the AP wake block to the jmp address */
+ movl $(sl_ap_jmp_offset - sl_txt_ap_wake_begin), \
+ (SL_mle_scratch + SL_SCRATCH_AP_JMP_OFFSET)(%eax)
+
+ /* Store the offset in the AP wake block to the AP stacks block */
+ movl $(sl_stacks - sl_txt_ap_wake_begin), \
+ (SL_mle_scratch + SL_SCRATCH_AP_STACKS_OFFSET)(%eax)
+
+ /* %eax still is the base of the OS-MLE block, save it */
+ pushl %eax
+
+ /* Relocate the AP wake code to the safe block */
+ call sl_txt_reloc_ap_wake
+
+ /*
+ * Wake up all APs that are blocked in the ACM and wait for them to
+ * halt. This should be done before restoring the MTRRs so the ACM is
+ * still properly in WB memory.
+ */
+ call sl_txt_wake_aps
+
+ /* Restore OS-MLE in %eax */
+ popl %eax
+
+ /*
+ * %edi is used by this routine to find the MTRRs which are in the SLRT
+ * in the Intel info.
+ */
+ movl SL_txt_info(%eax), %edi
+ call sl_txt_load_regs
+
+ jmp .Lcpu_setup_done
+
+.Ldo_unknown_cpu:
+ /* Non-Intel CPUs are not yet supported */
+ ud2
+
+.Lcpu_setup_done:
+ /*
+ * Don't enable MCE at this point. The kernel will enable
+ * it on the BSP later when it is ready.
+ */
+
+ /* Done, jump to normal 32b pm entry */
+ jmp startup_32
+SYM_FUNC_END(sl_stub_entry)
+
+SYM_FUNC_START(sl_find_mle_base)
+ /* %ecx has PDPT, get first PD */
+ movl (%ecx), %eax
+ andl $(PAGE_MASK), %eax
+ /* Get first PT from first PDE */
+ movl (%eax), %eax
+ andl $(PAGE_MASK), %eax
+ /* Get MLE base from first PTE */
+ movl (%eax), %eax
+ andl $(PAGE_MASK), %eax
+
+ movl %eax, rva(sl_mle_start)(%ebx)
+ ret
+SYM_FUNC_END(sl_find_mle_base)
+
+SYM_FUNC_START(sl_check_buffer_mle_overlap)
+ /* %ecx: buffer begin %edx: buffer end */
+ /* %ebx: MLE begin %edi: MLE end */
+ /* %eax: region may be inside MLE */
+
+ cmpl %edi, %ecx
+ jb .Lnext_check
+ cmpl %edi, %edx
+ jbe .Lnext_check
+ jmp .Lvalid /* Buffer above MLE */
+
+.Lnext_check:
+ cmpl %ebx, %edx
+ ja .Linside_check
+ cmpl %ebx, %ecx
+ jae .Linside_check
+ jmp .Lvalid /* Buffer below MLE */
+
+.Linside_check:
+ cmpl $0, %eax
+ jz .Linvalid
+ cmpl %ebx, %ecx
+ jb .Linvalid
+ cmpl %edi, %edx
+ ja .Linvalid
+ jmp .Lvalid /* Buffer in MLE */
+
+.Linvalid:
+ TXT_RESET $(SL_ERROR_MLE_BUFFER_OVERLAP)
+
+.Lvalid:
+ ret
+SYM_FUNC_END(sl_check_buffer_mle_overlap)
+
+SYM_FUNC_START(sl_txt_verify_os_mle_struct)
+ pushl %ebx
+ /*
+ * %eax points to the base of the OS-MLE struct. Need to also
+ * read some values from the OS-SINIT struct too.
+ */
+ movl -8(%eax), %ecx
+ /* Skip over OS to MLE data section and size of OS-SINIT structure */
+ leal (%eax, %ecx), %edx
+
+ /* Load MLE image base absolute offset */
+ movl rva(sl_mle_start)(%ebx), %ebx
+
+ /* Verify the value of the low PMR base. It should always be 0. */
+ movl SL_vtd_pmr_lo_base(%edx), %esi
+ cmpl $0, %esi
+ jz .Lvalid_pmr_base
+ TXT_RESET $(SL_ERROR_LO_PMR_BASE)
+
+.Lvalid_pmr_base:
+ /* Grab some values from OS-SINIT structure */
+ movl SL_mle_size(%edx), %edi
+ addl %ebx, %edi
+ jc .Loverflow_detected
+ movl SL_vtd_pmr_lo_size(%edx), %esi
+
+ /* Check the AP wake block */
+ movl SL_ap_wake_block(%eax), %ecx
+ movl SL_ap_wake_block_size(%eax), %edx
+ addl %ecx, %edx
+ jc .Loverflow_detected
+ pushl %eax
+ xorl %eax, %eax
+ call sl_check_buffer_mle_overlap
+ popl %eax
+ cmpl %esi, %edx
+ ja .Lbuffer_beyond_pmr
+
+ /*
+ * Check the boot params. Note during a UEFI boot, the boot
+ * params will be inside the MLE image. Test for this case
+ * in the overlap case.
+ */
+ movl SL_boot_params_addr(%eax), %ecx
+ movl $(PAGE_SIZE), %edx
+ addl %ecx, %edx
+ jc .Loverflow_detected
+ pushl %eax
+ movl $1, %eax
+ call sl_check_buffer_mle_overlap
+ popl %eax
+ cmpl %esi, %edx
+ ja .Lbuffer_beyond_pmr
+
+ /* Check that the AP wake block is big enough */
+ cmpl $(sl_txt_ap_wake_end - sl_txt_ap_wake_begin), \
+ SL_ap_wake_block_size(%eax)
+ jae .Lwake_block_ok
+ TXT_RESET $(SL_ERROR_WAKE_BLOCK_TOO_SMALL)
+
+.Lwake_block_ok:
+ popl %ebx
+ ret
+
+.Loverflow_detected:
+ TXT_RESET $(SL_ERROR_INTEGER_OVERFLOW)
+
+.Lbuffer_beyond_pmr:
+ TXT_RESET $(SL_ERROR_BUFFER_BEYOND_PMR)
+SYM_FUNC_END(sl_txt_verify_os_mle_struct)
+
+SYM_FUNC_START(sl_txt_ap_entry)
+ cli
+ cld
+ /*
+ * The %cs and %ds segments are known good after waking the AP.
+ * First order of business is to find where we are and
+ * save it in %ebx.
+ */
+
+ /* Read physical base of heap into EAX */
+ movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
+ /* Read the size of the BIOS data into ECX (first 8 bytes) */
+ movl (%eax), %ecx
+ /* Skip over BIOS data and size of OS to MLE data section */
+ leal 8(%eax, %ecx), %eax
+
+ /* Saved %ebx from the BSP and stash OS-MLE pointer */
+ movl (SL_mle_scratch + SL_SCRATCH_AP_EBX)(%eax), %ebx
+
+ /* Save TXT info ptr in %edi for call to sl_txt_load_regs */
+ movl SL_txt_info(%eax), %edi
+
+ /* Lock and get our stack index */
+ movl $1, %ecx
+.Lspin:
+ xorl %eax, %eax
+ lock cmpxchgl %ecx, rva(sl_txt_spin_lock)(%ebx)
+ pause
+ jnz .Lspin
+
+ /* Increment the stack index and use the next value inside lock */
+ incl rva(sl_txt_stack_index)(%ebx)
+ movl rva(sl_txt_stack_index)(%ebx), %eax
+
+ /* Unlock */
+ movl $0, rva(sl_txt_spin_lock)(%ebx)
+
+ /* Location of the relocated AP wake block */
+ movl rva(sl_txt_ap_wake_block)(%ebx), %ecx
+
+ /* Load reloc GDT, set segment regs and lret to __SL32_CS */
+ lgdt (sl_ap_gdt_desc - sl_txt_ap_wake_begin)(%ecx)
+
+ movl $(__SL32_DS), %edx
+ movw %dx, %ds
+ movw %dx, %es
+ movw %dx, %fs
+ movw %dx, %gs
+ movw %dx, %ss
+
+ /* Load our reloc AP stack */
+ movl $(TXT_BOOT_STACK_SIZE), %edx
+ mull %edx
+ leal (sl_stacks_end - sl_txt_ap_wake_begin)(%ecx), %esp
+ subl %eax, %esp
+
+ /* Switch to AP code segment */
+ leal rva(.Lsl_ap_cs)(%ebx), %eax
+ pushl $(__SL32_CS)
+ pushl %eax
+ lret
+
+.Lsl_ap_cs:
+ /* Load the relocated AP IDT */
+ lidt (sl_ap_idt_desc - sl_txt_ap_wake_begin)(%ecx)
+
+ /* Fixup MTRRs and misc enable MSR on APs too */
+ call sl_txt_load_regs
+
+ /* Enable SMI with GETSEC[SMCTRL] */
+ GETSEC $(SMX_X86_GETSEC_SMCTRL)
+
+ /* IRET-to-self can be used to enable NMIs which SENTER disabled */
+ leal rva(.Lnmi_enabled_ap)(%ebx), %eax
+ pushfl
+ pushl $(__SL32_CS)
+ pushl %eax
+ iret
+
+.Lnmi_enabled_ap:
+ /* Put APs in X2APIC mode like the BSP */
+ movl $(MSR_IA32_APICBASE), %ecx
+ rdmsr
+ orl $(XAPIC_ENABLE | X2APIC_ENABLE), %eax
+ wrmsr
+
+ /*
+ * Basically done, increment the CPU count and jump off to the AP
+ * wake block to wait.
+ */
+ lock incl rva(sl_txt_cpu_count)(%ebx)
+
+ movl rva(sl_txt_ap_wake_block)(%ebx), %eax
+ jmp *%eax
+SYM_FUNC_END(sl_txt_ap_entry)
+
+SYM_FUNC_START(sl_txt_reloc_ap_wake)
+ /* Save boot params register */
+ pushl %esi
+
+ movl rva(sl_txt_ap_wake_block)(%ebx), %edi
+
+ /* Fixup AP IDT and GDT descriptor before relocating */
+ leal rva(sl_ap_idt_desc)(%ebx), %eax
+ addl %edi, 2(%eax)
+ leal rva(sl_ap_gdt_desc)(%ebx), %eax
+ addl %edi, 2(%eax)
+
+ /*
+ * Copy the AP wake code and AP GDT/IDT to the protected wake block
+ * provided by the loader. Destination already in %edi.
+ */
+ movl $(sl_txt_ap_wake_end - sl_txt_ap_wake_begin), %ecx
+ leal rva(sl_txt_ap_wake_begin)(%ebx), %esi
+ rep movsb
+
+ /* Setup the IDT for the APs to use in the relocation block */
+ movl rva(sl_txt_ap_wake_block)(%ebx), %ecx
+ addl $(sl_ap_idt - sl_txt_ap_wake_begin), %ecx
+ xorl %edx, %edx
+
+ /* Form the default reset vector relocation address */
+ movl rva(sl_txt_ap_wake_block)(%ebx), %esi
+ addl $(sl_txt_int_reset - sl_txt_ap_wake_begin), %esi
+
+1:
+ cmpw $(NR_VECTORS), %dx
+ jz .Lap_idt_done
+
+ cmpw $(X86_TRAP_NMI), %dx
+ jz 2f
+
+ /* Load all other fixed vectors with reset handler */
+ movl %esi, %eax
+ movw %ax, (IDT_VECTOR_LO_BITS)(%ecx)
+ shrl $16, %eax
+ movw %ax, (IDT_VECTOR_HI_BITS)(%ecx)
+ jmp 3f
+
+2:
+ /* Load single wake NMI IPI vector at the relocation address */
+ movl rva(sl_txt_ap_wake_block)(%ebx), %eax
+ addl $(sl_txt_int_nmi - sl_txt_ap_wake_begin), %eax
+ movw %ax, (IDT_VECTOR_LO_BITS)(%ecx)
+ shrl $16, %eax
+ movw %ax, (IDT_VECTOR_HI_BITS)(%ecx)
+
+3:
+ incw %dx
+ addl $8, %ecx
+ jmp 1b
+
+.Lap_idt_done:
+ popl %esi
+ ret
+SYM_FUNC_END(sl_txt_reloc_ap_wake)
+
+SYM_FUNC_START(sl_txt_load_regs)
+ /* Save base pointer register */
+ pushl %ebx
+
+ /*
+ * On Intel, the original variable MTRRs and Misc Enable MSR are
+ * restored on the BSP at early boot. Each AP will also restore
+ * its MTRRs and Misc Enable MSR.
+ */
+ pushl %edi
+ addl $(SL_saved_bsp_mtrrs), %edi
+ movl (%edi), %ebx
+ pushl %ebx /* default_mem_type lo */
+ addl $4, %edi
+ movl (%edi), %ebx
+ pushl %ebx /* default_mem_type hi */
+ addl $4, %edi
+ movl (%edi), %ebx /* mtrr_vcnt lo, don't care about hi part */
+ addl $8, %edi /* now at MTRR pair array */
+ /* Write the variable MTRRs */
+ movl $(MSR_MTRRphysBase0), %ecx
+1:
+ cmpl $0, %ebx
+ jz 2f
+
+ movl (%edi), %eax /* MTRRphysBaseX lo */
+ addl $4, %edi
+ movl (%edi), %edx /* MTRRphysBaseX hi */
+ wrmsr
+ addl $4, %edi
+ incl %ecx
+ movl (%edi), %eax /* MTRRphysMaskX lo */
+ addl $4, %edi
+ movl (%edi), %edx /* MTRRphysMaskX hi */
+ wrmsr
+ addl $4, %edi
+ incl %ecx
+
+ decl %ebx
+ jmp 1b
+2:
+ /* Write the default MTRR register */
+ popl %edx
+ popl %eax
+ movl $(MSR_MTRRdefType), %ecx
+ wrmsr
+
+ /* Return to beginning and write the misc enable msr */
+ popl %edi
+ addl $(SL_saved_misc_enable_msr), %edi
+ movl (%edi), %eax /* saved_misc_enable_msr lo */
+ addl $4, %edi
+ movl (%edi), %edx /* saved_misc_enable_msr hi */
+ movl $(MSR_IA32_MISC_ENABLE), %ecx
+ wrmsr
+
+ popl %ebx
+ ret
+SYM_FUNC_END(sl_txt_load_regs)
+
+SYM_FUNC_START(sl_txt_wake_aps)
+ /* Save boot params register */
+ pushl %esi
+
+ /* First setup the MLE join structure and load it into TXT reg */
+ leal rva(sl_gdt)(%ebx), %eax
+ leal rva(sl_txt_ap_entry)(%ebx), %ecx
+ leal rva(sl_smx_rlp_mle_join)(%ebx), %edx
+ movl %eax, SL_rlp_gdt_base(%edx)
+ movl %ecx, SL_rlp_entry_point(%edx)
+ movl %edx, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_MLE_JOIN)
+
+ /* Another TXT heap walk to find various values needed to wake APs */
+ movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
+ /* At BIOS data size, find the number of logical processors */
+ movl (SL_num_logical_procs + 8)(%eax), %edx
+ /* Skip over BIOS data */
+ movl (%eax), %ecx
+ addl %ecx, %eax
+ /* Skip over OS to MLE */
+ movl (%eax), %ecx
+ addl %ecx, %eax
+ /* At OS-SNIT size, get capabilities to know how to wake up the APs */
+ movl (SL_capabilities + 8)(%eax), %esi
+ /* Skip over OS to SNIT */
+ movl (%eax), %ecx
+ addl %ecx, %eax
+ /* At SINIT-MLE size, get the AP wake MONITOR address */
+ movl (SL_rlp_wakeup_addr + 8)(%eax), %edi
+
+ /* Determine how to wake up the APs */
+ testl $(1 << TXT_SINIT_MLE_CAP_WAKE_MONITOR), %esi
+ jz .Lwake_getsec
+
+ /* Wake using MWAIT MONITOR */
+ movl $1, (%edi)
+ jmp .Laps_awake
+
+.Lwake_getsec:
+ /* Wake using GETSEC(WAKEUP) */
+ GETSEC $(SMX_X86_GETSEC_WAKEUP)
+
+.Laps_awake:
+ /*
+ * All of the APs are woken up and rendesvous in the relocated wake
+ * block starting at sl_txt_ap_wake_begin. Wait for all of them to
+ * halt.
+ */
+ pause
+ cmpl rva(sl_txt_cpu_count)(%ebx), %edx
+ jne .Laps_awake
+
+ popl %esi
+ ret
+SYM_FUNC_END(sl_txt_wake_aps)
+
+/* This is the beginning of the relocated AP wake code block */
+ .global sl_txt_ap_wake_begin
+sl_txt_ap_wake_begin:
+
+ /* Get the LAPIC ID for each AP and stash it on the stack */
+ movl $(MSR_IA32_X2APIC_APICID), %ecx
+ rdmsr
+ pushl %eax
+
+ /*
+ * Get a pointer to the monitor location on this APs stack to test below
+ * after mwait returns. Currently %esp points to just past the pushed APIC
+ * ID value.
+ */
+ movl %esp, %eax
+ subl $(TXT_BOOT_STACK_SIZE - 4), %eax
+ movl $0, (%eax)
+
+ /* Clear ecx/edx so no invalid extensions or hints are passed to monitor */
+ xorl %ecx, %ecx
+ xorl %edx, %edx
+
+ /*
+ * Arm the monitor and wait for it to be poked by he SMP bringup code. The mwait
+ * instruction can return for a number of reasons. Test to see if it returned
+ * because the monitor was written to.
+ */
+ monitor
+
+1:
+ mfence
+ mwait
+ movl (%eax), %edx
+ testl %edx, %edx
+ jz 1b
+
+ /*
+ * This is the long absolute jump to the 32b Secure Launch protected mode stub
+ * code in sl_trampoline_start32() in the rmpiggy. The jump address will be
+ * fixed in the SMP boot code when the first AP is brought up. This whole area
+ * is provided and protected in the memory map by the prelaunch code.
+ */
+ .byte 0xea
+sl_ap_jmp_offset:
+ .long 0x00000000
+ .word __SL32_CS
+
+SYM_FUNC_START(sl_txt_int_nmi)
+ /* NMI context, just IRET */
+ iret
+SYM_FUNC_END(sl_txt_int_nmi)
+
+SYM_FUNC_START(sl_txt_int_reset)
+ TXT_RESET $(SL_ERROR_INV_AP_INTERRUPT)
+SYM_FUNC_END(sl_txt_int_reset)
+
+ .balign 8
+SYM_DATA_START_LOCAL(sl_ap_idt_desc)
+ .word sl_ap_idt_end - sl_ap_idt - 1 /* Limit */
+ .long sl_ap_idt - sl_txt_ap_wake_begin /* Base */
+SYM_DATA_END_LABEL(sl_ap_idt_desc, SYM_L_LOCAL, sl_ap_idt_desc_end)
+
+ .balign 8
+SYM_DATA_START_LOCAL(sl_ap_idt)
+ .rept NR_VECTORS
+ .word 0x0000 /* Offset 15 to 0 */
+ .word __SL32_CS /* Segment selector */
+ .word 0x8e00 /* Present, DPL=0, 32b Vector, Interrupt */
+ .word 0x0000 /* Offset 31 to 16 */
+ .endr
+SYM_DATA_END_LABEL(sl_ap_idt, SYM_L_LOCAL, sl_ap_idt_end)
+
+ .balign 8
+SYM_DATA_START_LOCAL(sl_ap_gdt_desc)
+ .word sl_ap_gdt_end - sl_ap_gdt - 1
+ .long sl_ap_gdt - sl_txt_ap_wake_begin
+SYM_DATA_END_LABEL(sl_ap_gdt_desc, SYM_L_LOCAL, sl_ap_gdt_desc_end)
+
+ .balign 8
+SYM_DATA_START_LOCAL(sl_ap_gdt)
+ .quad 0x0000000000000000 /* NULL */
+ .quad 0x00cf9a000000ffff /* __SL32_CS */
+ .quad 0x00cf92000000ffff /* __SL32_DS */
+SYM_DATA_END_LABEL(sl_ap_gdt, SYM_L_LOCAL, sl_ap_gdt_end)
+
+ /* Small stacks for BSP and APs to work with */
+ .balign 64
+SYM_DATA_START_LOCAL(sl_stacks)
+ .fill (TXT_MAX_CPUS * TXT_BOOT_STACK_SIZE), 1, 0
+SYM_DATA_END_LABEL(sl_stacks, SYM_L_LOCAL, sl_stacks_end)
+
+/* This is the end of the relocated AP wake code block */
+ .global sl_txt_ap_wake_end
+sl_txt_ap_wake_end:
+
+ .data
+ .balign 8
+SYM_DATA_START_LOCAL(sl_gdt_desc)
+ .word sl_gdt_end - sl_gdt - 1
+ .long sl_gdt - sl_gdt_desc
+SYM_DATA_END_LABEL(sl_gdt_desc, SYM_L_LOCAL, sl_gdt_desc_end)
+
+ .balign 8
+SYM_DATA_START_LOCAL(sl_gdt)
+ .quad 0x0000000000000000 /* NULL */
+ .quad 0x00cf9a000000ffff /* __SL32_CS */
+ .quad 0x00cf92000000ffff /* __SL32_DS */
+SYM_DATA_END_LABEL(sl_gdt, SYM_L_LOCAL, sl_gdt_end)
+
+ .balign 8
+SYM_DATA_START_LOCAL(sl_smx_rlp_mle_join)
+ .long sl_gdt_end - sl_gdt - 1 /* GDT limit */
+ .long 0x00000000 /* GDT base */
+ .long __SL32_CS /* Seg Sel - CS (DS, ES, SS = seg_sel+8) */
+ .long 0x00000000 /* Entry point physical address */
+SYM_DATA_END(sl_smx_rlp_mle_join)
+
+SYM_DATA(sl_cpu_type, .long 0x00000000)
+
+SYM_DATA(sl_mle_start, .long 0x00000000)
+
+SYM_DATA_LOCAL(sl_txt_spin_lock, .long 0x00000000)
+
+SYM_DATA_LOCAL(sl_txt_stack_index, .long 0x00000000)
+
+SYM_DATA_LOCAL(sl_txt_cpu_count, .long 0x00000000)
+
+SYM_DATA_LOCAL(sl_txt_ap_wake_block, .long 0x00000000)
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index e022e6eb766c..37f6167f28ba 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -348,6 +348,9 @@
#define MSR_IA32_RTIT_OUTPUT_BASE 0x00000560
#define MSR_IA32_RTIT_OUTPUT_MASK 0x00000561

+#define MSR_MTRRphysBase0 0x00000200
+#define MSR_MTRRphysMask0 0x00000201
+
#define MSR_MTRRfix64K_00000 0x00000250
#define MSR_MTRRfix16K_80000 0x00000258
#define MSR_MTRRfix16K_A0000 0x00000259
@@ -849,6 +852,8 @@
#define MSR_IA32_APICBASE_ENABLE (1<<11)
#define MSR_IA32_APICBASE_BASE (0xfffff<<12)

+#define MSR_IA32_X2APIC_APICID 0x00000802
+
#define MSR_IA32_UCODE_WRITE 0x00000079
#define MSR_IA32_UCODE_REV 0x0000008b

diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index 9b82eebd7add..7ce283a22d6b 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -12,6 +12,7 @@
/* loadflags */
#define LOADED_HIGH (1<<0)
#define KASLR_FLAG (1<<1)
+#define SLAUNCH_FLAG (1<<2)
#define QUIET_FLAG (1<<5)
#define KEEP_SEGMENTS (1<<6)
#define CAN_USE_HEAP (1<<7)
diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
index a98020bf31bb..925adce6e2c7 100644
--- a/arch/x86/kernel/asm-offsets.c
+++ b/arch/x86/kernel/asm-offsets.c
@@ -13,6 +13,8 @@
#include <linux/hardirq.h>
#include <linux/suspend.h>
#include <linux/kbuild.h>
+#include <linux/slr_table.h>
+#include <linux/slaunch.h>
#include <asm/processor.h>
#include <asm/thread_info.h>
#include <asm/sigframe.h>
@@ -120,4 +122,22 @@ static void __used common(void)
OFFSET(ARIA_CTX_rounds, aria_ctx, rounds);
#endif

+#ifdef CONFIG_SECURE_LAUNCH
+ BLANK();
+ OFFSET(SL_txt_info, txt_os_mle_data, txt_info);
+ OFFSET(SL_mle_scratch, txt_os_mle_data, mle_scratch);
+ OFFSET(SL_boot_params_addr, txt_os_mle_data, boot_params_addr);
+ OFFSET(SL_ap_wake_block, txt_os_mle_data, ap_wake_block);
+ OFFSET(SL_ap_wake_block_size, txt_os_mle_data, ap_wake_block_size);
+ OFFSET(SL_saved_misc_enable_msr, slr_entry_intel_info, saved_misc_enable_msr);
+ OFFSET(SL_saved_bsp_mtrrs, slr_entry_intel_info, saved_bsp_mtrrs);
+ OFFSET(SL_num_logical_procs, txt_bios_data, num_logical_procs);
+ OFFSET(SL_capabilities, txt_os_sinit_data, capabilities);
+ OFFSET(SL_mle_size, txt_os_sinit_data, mle_size);
+ OFFSET(SL_vtd_pmr_lo_base, txt_os_sinit_data, vtd_pmr_lo_base);
+ OFFSET(SL_vtd_pmr_lo_size, txt_os_sinit_data, vtd_pmr_lo_size);
+ OFFSET(SL_rlp_wakeup_addr, txt_sinit_mle_data, rlp_wakeup_addr);
+ OFFSET(SL_rlp_gdt_base, smx_rlp_mle_join, rlp_gdt_base);
+ OFFSET(SL_rlp_entry_point, smx_rlp_mle_join, rlp_entry_point);
+#endif
}
--
2.39.3

2024-05-31 01:34:19

by Ross Philipson

Subject: [PATCH v9 05/19] x86: Secure Launch main header file

Introduce the main Secure Launch header file used in the early SL stub
and the early setup code.

Signed-off-by: Ross Philipson <[email protected]>
---
include/linux/slaunch.h | 542 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 542 insertions(+)
create mode 100644 include/linux/slaunch.h

diff --git a/include/linux/slaunch.h b/include/linux/slaunch.h
new file mode 100644
index 000000000000..90a7f22ddbdd
--- /dev/null
+++ b/include/linux/slaunch.h
@@ -0,0 +1,542 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Main Secure Launch header file.
+ *
+ * Copyright (c) 2024, Oracle and/or its affiliates.
+ */
+
+#ifndef _LINUX_SLAUNCH_H
+#define _LINUX_SLAUNCH_H
+
+/*
+ * Secure Launch Defined State Flags
+ */
+#define SL_FLAG_ACTIVE 0x00000001
+#define SL_FLAG_ARCH_SKINIT 0x00000002
+#define SL_FLAG_ARCH_TXT 0x00000004
+
+/*
+ * Secure Launch CPU Type
+ */
+#define SL_CPU_AMD 1
+#define SL_CPU_INTEL 2
+
+#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
+
+#define __SL32_CS 0x0008
+#define __SL32_DS 0x0010
+
+/*
+ * Intel Safer Mode Extensions (SMX)
+ *
+ * Intel SMX provides a programming interface to establish a Measured Launched
+ * Environment (MLE). The measurement and protection mechanisms supported by the
+ * capabilities of an Intel Trusted Execution Technology (TXT) platform. SMX is
+ * the processor’s programming interface in an Intel TXT platform.
+ *
+ * See Intel SDM Volume 2 - 6.1 "Safer Mode Extensions Reference"
+ */
+
+/*
+ * SMX GETSEC Leaf Functions
+ */
+#define SMX_X86_GETSEC_SEXIT 5
+#define SMX_X86_GETSEC_SMCTRL 7
+#define SMX_X86_GETSEC_WAKEUP 8
+
+/*
+ * Intel Trusted Execution Technology MMIO Registers Banks
+ */
+#define TXT_PUB_CONFIG_REGS_BASE 0xfed30000
+#define TXT_PRIV_CONFIG_REGS_BASE 0xfed20000
+#define TXT_NR_CONFIG_PAGES ((TXT_PUB_CONFIG_REGS_BASE - \
+ TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT)
+
+/*
+ * Intel Trusted Execution Technology (TXT) Registers
+ */
+#define TXT_CR_STS 0x0000
+#define TXT_CR_ESTS 0x0008
+#define TXT_CR_ERRORCODE 0x0030
+#define TXT_CR_CMD_RESET 0x0038
+#define TXT_CR_CMD_CLOSE_PRIVATE 0x0048
+#define TXT_CR_DIDVID 0x0110
+#define TXT_CR_VER_EMIF 0x0200
+#define TXT_CR_CMD_UNLOCK_MEM_CONFIG 0x0218
+#define TXT_CR_SINIT_BASE 0x0270
+#define TXT_CR_SINIT_SIZE 0x0278
+#define TXT_CR_MLE_JOIN 0x0290
+#define TXT_CR_HEAP_BASE 0x0300
+#define TXT_CR_HEAP_SIZE 0x0308
+#define TXT_CR_SCRATCHPAD 0x0378
+#define TXT_CR_CMD_OPEN_LOCALITY1 0x0380
+#define TXT_CR_CMD_CLOSE_LOCALITY1 0x0388
+#define TXT_CR_CMD_OPEN_LOCALITY2 0x0390
+#define TXT_CR_CMD_CLOSE_LOCALITY2 0x0398
+#define TXT_CR_CMD_SECRETS 0x08e0
+#define TXT_CR_CMD_NO_SECRETS 0x08e8
+#define TXT_CR_E2STS 0x08f0
+
+/* TXT default register value */
+#define TXT_REGVALUE_ONE 0x1ULL
+
+/* TXTCR_STS status bits */
+#define TXT_SENTER_DONE_STS BIT(0)
+#define TXT_SEXIT_DONE_STS BIT(1)
+
+/*
+ * SINIT/MLE Capabilities Field Bit Definitions
+ */
+#define TXT_SINIT_MLE_CAP_WAKE_GETSEC 0
+#define TXT_SINIT_MLE_CAP_WAKE_MONITOR 1
+
+/*
+ * OS/MLE Secure Launch Specific Definitions
+ */
+#define TXT_OS_MLE_STRUCT_VERSION 1
+#define TXT_OS_MLE_MAX_VARIABLE_MTRRS 32
+
+/*
+ * TXT Heap Table Enumeration
+ */
+#define TXT_BIOS_DATA_TABLE 1
+#define TXT_OS_MLE_DATA_TABLE 2
+#define TXT_OS_SINIT_DATA_TABLE 3
+#define TXT_SINIT_MLE_DATA_TABLE 4
+#define TXT_SINIT_TABLE_MAX TXT_SINIT_MLE_DATA_TABLE
+
+/*
+ * Secure Launch Defined Error Codes used in MLE-initiated TXT resets.
+ *
+ * TXT Specification
+ * Appendix I ACM Error Codes
+ */
+#define SL_ERROR_GENERIC 0xc0008001
+#define SL_ERROR_TPM_INIT 0xc0008002
+#define SL_ERROR_TPM_INVALID_LOG20 0xc0008003
+#define SL_ERROR_TPM_LOGGING_FAILED 0xc0008004
+#define SL_ERROR_REGION_STRADDLE_4GB 0xc0008005
+#define SL_ERROR_TPM_EXTEND 0xc0008006
+#define SL_ERROR_MTRR_INV_VCNT 0xc0008007
+#define SL_ERROR_MTRR_INV_DEF_TYPE 0xc0008008
+#define SL_ERROR_MTRR_INV_BASE 0xc0008009
+#define SL_ERROR_MTRR_INV_MASK 0xc000800a
+#define SL_ERROR_MSR_INV_MISC_EN 0xc000800b
+#define SL_ERROR_INV_AP_INTERRUPT 0xc000800c
+#define SL_ERROR_INTEGER_OVERFLOW 0xc000800d
+#define SL_ERROR_HEAP_WALK 0xc000800e
+#define SL_ERROR_HEAP_MAP 0xc000800f
+#define SL_ERROR_REGION_ABOVE_4GB 0xc0008010
+#define SL_ERROR_HEAP_INVALID_DMAR 0xc0008011
+#define SL_ERROR_HEAP_DMAR_SIZE 0xc0008012
+#define SL_ERROR_HEAP_DMAR_MAP 0xc0008013
+#define SL_ERROR_HI_PMR_BASE 0xc0008014
+#define SL_ERROR_HI_PMR_SIZE 0xc0008015
+#define SL_ERROR_LO_PMR_BASE 0xc0008016
+#define SL_ERROR_LO_PMR_MLE 0xc0008017
+#define SL_ERROR_INITRD_TOO_BIG 0xc0008018
+#define SL_ERROR_HEAP_ZERO_OFFSET 0xc0008019
+#define SL_ERROR_WAKE_BLOCK_TOO_SMALL 0xc000801a
+#define SL_ERROR_MLE_BUFFER_OVERLAP 0xc000801b
+#define SL_ERROR_BUFFER_BEYOND_PMR 0xc000801c
+#define SL_ERROR_OS_SINIT_BAD_VERSION 0xc000801d
+#define SL_ERROR_EVENTLOG_MAP 0xc000801e
+#define SL_ERROR_TPM_NUMBER_ALGS 0xc000801f
+#define SL_ERROR_TPM_UNKNOWN_DIGEST 0xc0008020
+#define SL_ERROR_TPM_INVALID_EVENT 0xc0008021
+#define SL_ERROR_INVALID_SLRT 0xc0008022
+#define SL_ERROR_SLRT_MISSING_ENTRY 0xc0008023
+#define SL_ERROR_SLRT_MAP 0xc0008024
+
+/*
+ * Secure Launch Defined Limits
+ */
+#define TXT_MAX_CPUS 512
+#define TXT_BOOT_STACK_SIZE 128
+
+/*
+ * Secure Launch event log entry type. The TXT specification defines the
+ * base event value as 0x400 for DRTM values.
+ */
+#define TXT_EVTYPE_BASE 0x400
+#define TXT_EVTYPE_SLAUNCH (TXT_EVTYPE_BASE + 0x102)
+#define TXT_EVTYPE_SLAUNCH_START (TXT_EVTYPE_BASE + 0x103)
+#define TXT_EVTYPE_SLAUNCH_END (TXT_EVTYPE_BASE + 0x104)
+
+/*
+ * Measured Launch PCRs
+ */
+#define SL_DEF_DLME_DETAIL_PCR17 17
+#define SL_DEF_DLME_AUTHORITY_PCR18 18
+#define SL_ALT_DLME_AUTHORITY_PCR19 19
+#define SL_ALT_DLME_DETAIL_PCR20 20
+
+/*
+ * MLE scratch area offsets
+ */
+#define SL_SCRATCH_AP_EBX 0
+#define SL_SCRATCH_AP_JMP_OFFSET 4
+#define SL_SCRATCH_AP_STACKS_OFFSET 8
+
+#ifndef __ASSEMBLY__
+
+#include <linux/io.h>
+#include <linux/tpm.h>
+#include <linux/tpm_eventlog.h>
+
+/*
+ * Secure Launch AP stack and monitor block
+ */
+struct sl_ap_stack_and_monitor {
+ u32 monitor;
+ u32 cache_pad[15];
+ u32 stack_pad[15];
+ u32 apicid;
+} __packed;
+
+/*
+ * Secure Launch AP wakeup information fetched in SMP boot code.
+ */
+struct sl_ap_wake_info {
+ u32 ap_wake_block;
+ u32 ap_wake_block_size;
+ u32 ap_jmp_offset;
+ u32 ap_stacks_offset;
+};
+
+/*
+ * TXT heap extended data elements.
+ */
+struct txt_heap_ext_data_element {
+ u32 type;
+ u32 size;
+ /* Data */
+} __packed;
+
+#define TXT_HEAP_EXTDATA_TYPE_END 0
+
+struct txt_heap_end_element {
+ u32 type;
+ u32 size;
+} __packed;
+
+#define TXT_HEAP_EXTDATA_TYPE_TPM_EVENT_LOG_PTR 5
+
+struct txt_heap_event_log_element {
+ u64 event_log_phys_addr;
+} __packed;
+
+#define TXT_HEAP_EXTDATA_TYPE_EVENT_LOG_POINTER2_1 8
+
+struct txt_heap_event_log_pointer2_1_element {
+ u64 phys_addr;
+ u32 allocated_event_container_size;
+ u32 first_record_offset;
+ u32 next_record_offset;
+} __packed;
+
+/*
+ * Secure Launch defined OS/MLE TXT Heap table
+ */
+struct txt_os_mle_data {
+ u32 version;
+ u32 boot_params_addr;
+ u64 slrt;
+ u64 txt_info;
+ u32 ap_wake_block;
+ u32 ap_wake_block_size;
+ u8 mle_scratch[64];
+} __packed;
+
+/*
+ * TXT specification defined BIOS data TXT Heap table
+ */
+struct txt_bios_data {
+ u32 version; /* Currently 5 for TPM 1.2 and 6 for TPM 2.0 */
+ u32 bios_sinit_size;
+ u64 reserved1;
+ u64 reserved2;
+ u32 num_logical_procs;
+ /* Versions >= 5 with updates in version 6 */
+ u32 sinit_flags;
+ u32 mle_flags;
+ /* Versions >= 4 */
+ /* Ext Data Elements */
+} __packed;
+
+/*
+ * TXT specification defined OS/SINIT TXT Heap table
+ */
+struct txt_os_sinit_data {
+ u32 version; /* Currently 6 for TPM 1.2 and 7 for TPM 2.0 */
+ u32 flags;
+ u64 mle_ptab;
+ u64 mle_size;
+ u64 mle_hdr_base;
+ u64 vtd_pmr_lo_base;
+ u64 vtd_pmr_lo_size;
+ u64 vtd_pmr_hi_base;
+ u64 vtd_pmr_hi_size;
+ u64 lcp_po_base;
+ u64 lcp_po_size;
+ u32 capabilities;
+ /* Version = 5 */
+ u64 efi_rsdt_ptr;
+ /* Versions >= 6 */
+ /* Ext Data Elements */
+} __packed;
+
+/*
+ * TXT specification defined SINIT/MLE TXT Heap table
+ */
+struct txt_sinit_mle_data {
+ u32 version; /* Current values are 6 through 9 */
+ /* Versions <= 8 */
+ u8 bios_acm_id[20];
+ u32 edx_senter_flags;
+ u64 mseg_valid;
+ u8 sinit_hash[20];
+ u8 mle_hash[20];
+ u8 stm_hash[20];
+ u8 lcp_policy_hash[20];
+ u32 lcp_policy_control;
+ /* Versions >= 7 */
+ u32 rlp_wakeup_addr;
+ u32 reserved;
+ u32 num_of_sinit_mdrs;
+ u32 sinit_mdrs_table_offset;
+ u32 sinit_vtd_dmar_table_size;
+ u32 sinit_vtd_dmar_table_offset;
+ /* Versions >= 8 */
+ u32 processor_scrtm_status;
+ /* Versions >= 9 */
+ /* Ext Data Elements */
+} __packed;
+
+/*
+ * TXT data reporting structure for memory types
+ */
+struct txt_sinit_memory_descriptor_record {
+ u64 address;
+ u64 length;
+ u8 type;
+ u8 reserved[7];
+} __packed;
+
+/*
+ * TXT data structure used by a responsive local processor (RLP) to start
+ * execution in response to a GETSEC[WAKEUP].
+ */
+struct smx_rlp_mle_join {
+ u32 rlp_gdt_limit;
+ u32 rlp_gdt_base;
+ u32 rlp_seg_sel; /* cs (ds, es, ss are seg_sel+8) */
+ u32 rlp_entry_point; /* phys addr */
+} __packed;
+
+/*
+ * TPM event log structures defined in both the TXT specification and
+ * the TCG documentation.
+ */
+#define TPM12_EVTLOG_SIGNATURE "TXT Event Container"
+
+struct tpm12_event_log_header {
+ char signature[20];
+ char reserved[12];
+ u8 container_ver_major;
+ u8 container_ver_minor;
+ u8 pcr_event_ver_major;
+ u8 pcr_event_ver_minor;
+ u32 container_size;
+ u32 pcr_events_offset;
+ u32 next_event_offset;
+ /* PCREvents[] */
+} __packed;
+
+/*
+ * Functions to extract data from the Intel TXT Heap Memory. The layout
+ * of the heap is as follows:
+ * +----------------------------+
+ * | Size Bios Data table (u64) |
+ * +----------------------------+
+ * | Bios Data table |
+ * +----------------------------+
+ * | Size OS MLE table (u64) |
+ * +----------------------------+
+ * | OS MLE table |
+ * +--------------------------- +
+ * | Size OS SINIT table (u64) |
+ * +----------------------------+
+ * | OS SINIT table |
+ * +----------------------------+
+ * | Size SINIT MLE table (u64) |
+ * +----------------------------+
+ * | SINIT MLE table |
+ * +----------------------------+
+ *
+ * NOTE: the table size fields include the 8 byte size field itself.
+ */
+static inline u64 txt_bios_data_size(void *heap)
+{
+ return *((u64 *)heap);
+}
+
+static inline void *txt_bios_data_start(void *heap)
+{
+ return heap + sizeof(u64);
+}
+
+static inline u64 txt_os_mle_data_size(void *heap)
+{
+ return *((u64 *)(heap + txt_bios_data_size(heap)));
+}
+
+static inline void *txt_os_mle_data_start(void *heap)
+{
+ return heap + txt_bios_data_size(heap) + sizeof(u64);
+}
+
+static inline u64 txt_os_sinit_data_size(void *heap)
+{
+ return *((u64 *)(heap + txt_bios_data_size(heap) +
+ txt_os_mle_data_size(heap)));
+}
+
+static inline void *txt_os_sinit_data_start(void *heap)
+{
+ return heap + txt_bios_data_size(heap) +
+ txt_os_mle_data_size(heap) + sizeof(u64);
+}
+
+static inline u64 txt_sinit_mle_data_size(void *heap)
+{
+ return *((u64 *)(heap + txt_bios_data_size(heap) +
+ txt_os_mle_data_size(heap) +
+ txt_os_sinit_data_size(heap)));
+}
+
+static inline void *txt_sinit_mle_data_start(void *heap)
+{
+ return heap + txt_bios_data_size(heap) +
+ txt_os_mle_data_size(heap) +
+ txt_os_sinit_data_size(heap) + sizeof(u64);
+}
+
+/*
+ * TPM event logging functions.
+ */
+static inline struct txt_heap_event_log_pointer2_1_element*
+tpm20_find_log2_1_element(struct txt_os_sinit_data *os_sinit_data)
+{
+ struct txt_heap_ext_data_element *ext_elem;
+
+ /* The extended element array as at the end of this table */
+ ext_elem = (struct txt_heap_ext_data_element *)
+ ((u8 *)os_sinit_data + sizeof(struct txt_os_sinit_data));
+
+ while (ext_elem->type != TXT_HEAP_EXTDATA_TYPE_END) {
+ if (ext_elem->type ==
+ TXT_HEAP_EXTDATA_TYPE_EVENT_LOG_POINTER2_1) {
+ return (struct txt_heap_event_log_pointer2_1_element *)
+ ((u8 *)ext_elem +
+ sizeof(struct txt_heap_ext_data_element));
+ }
+ ext_elem =
+ (struct txt_heap_ext_data_element *)
+ ((u8 *)ext_elem + ext_elem->size);
+ }
+
+ return NULL;
+}
+
+static inline int tpm12_log_event(void *evtlog_base, u32 evtlog_size,
+ u32 event_size, void *event)
+{
+ struct tpm12_event_log_header *evtlog =
+ (struct tpm12_event_log_header *)evtlog_base;
+
+ if (memcmp(evtlog->signature, TPM12_EVTLOG_SIGNATURE,
+ sizeof(TPM12_EVTLOG_SIGNATURE)))
+ return -EINVAL;
+
+ if (evtlog->container_size > evtlog_size)
+ return -EINVAL;
+
+ if (evtlog->next_event_offset + event_size > evtlog->container_size)
+ return -E2BIG;
+
+ memcpy(evtlog_base + evtlog->next_event_offset, event, event_size);
+ evtlog->next_event_offset += event_size;
+
+ return 0;
+}
+
+static inline int tpm20_log_event(struct txt_heap_event_log_pointer2_1_element *elem,
+ void *evtlog_base, u32 evtlog_size,
+ u32 event_size, void *event)
+{
+ struct tcg_pcr_event *header =
+ (struct tcg_pcr_event *)evtlog_base;
+
+ /* Has to be at least big enough for the signature */
+ if (header->event_size < sizeof(TCG_SPECID_SIG))
+ return -EINVAL;
+
+ if (memcmp((u8 *)header + sizeof(struct tcg_pcr_event),
+ TCG_SPECID_SIG, sizeof(TCG_SPECID_SIG)))
+ return -EINVAL;
+
+ if (elem->allocated_event_container_size > evtlog_size)
+ return -EINVAL;
+
+ if (elem->next_record_offset + event_size >
+ elem->allocated_event_container_size)
+ return -E2BIG;
+
+ memcpy(evtlog_base + elem->next_record_offset, event, event_size);
+ elem->next_record_offset += event_size;
+
+ return 0;
+}
+
+/*
+ * External functions avalailable in mainline kernel.
+ */
+void slaunch_setup_txt(void);
+void slaunch_fixup_jump_vector(void);
+u32 slaunch_get_flags(void);
+struct sl_ap_wake_info *slaunch_get_ap_wake_info(void);
+struct acpi_table_header *slaunch_get_dmar_table(struct acpi_table_header *dmar);
+void __noreturn slaunch_txt_reset(void __iomem *txt,
+ const char *msg, u64 error);
+extern void slaunch_finalize(int do_sexit);
+
+#endif /* !__ASSEMBLY */
+
+#else
+
+static inline void slaunch_setup_txt(void)
+{
+}
+
+static inline void slaunch_fixup_jump_vector(void)
+{
+}
+
+static inline u32 slaunch_get_flags(void)
+{
+ return 0;
+}
+
+static inline struct acpi_table_header *slaunch_get_dmar_table(struct acpi_table_header *dmar)
+{
+ return dmar;
+}
+
+static inline void slaunch_finalize(int do_sexit)
+{
+}
+
+#endif /* !IS_ENABLED(CONFIG_SECURE_LAUNCH) */
+
+#endif /* _LINUX_SLAUNCH_H */
--
2.39.3

2024-05-31 01:34:32

by Ross Philipson

Subject: [PATCH v9 02/19] Documentation/x86: Secure Launch kernel documentation

Introduce background, overview and configuration/ABI information
for the Secure Launch kernel feature.

Signed-off-by: Daniel P. Smith <[email protected]>
Signed-off-by: Ross Philipson <[email protected]>
Reviewed-by: Bagas Sanjaya <[email protected]>
---
Documentation/security/index.rst | 1 +
.../security/launch-integrity/index.rst | 11 +
.../security/launch-integrity/principles.rst | 320 ++++++++++
.../secure_launch_details.rst | 587 ++++++++++++++++++
.../secure_launch_overview.rst | 227 +++++++
5 files changed, 1146 insertions(+)
create mode 100644 Documentation/security/launch-integrity/index.rst
create mode 100644 Documentation/security/launch-integrity/principles.rst
create mode 100644 Documentation/security/launch-integrity/secure_launch_details.rst
create mode 100644 Documentation/security/launch-integrity/secure_launch_overview.rst

diff --git a/Documentation/security/index.rst b/Documentation/security/index.rst
index 59f8fc106cb0..56e31fb3d91f 100644
--- a/Documentation/security/index.rst
+++ b/Documentation/security/index.rst
@@ -19,3 +19,4 @@ Security Documentation
digsig
landlock
secrets/index
+ launch-integrity/index
diff --git a/Documentation/security/launch-integrity/index.rst b/Documentation/security/launch-integrity/index.rst
new file mode 100644
index 000000000000..838328186dd2
--- /dev/null
+++ b/Documentation/security/launch-integrity/index.rst
@@ -0,0 +1,11 @@
+=====================================
+System Launch Integrity documentation
+=====================================
+
+.. toctree::
+ :maxdepth: 1
+
+ principles
+ secure_launch_overview
+ secure_launch_details
+
diff --git a/Documentation/security/launch-integrity/principles.rst b/Documentation/security/launch-integrity/principles.rst
new file mode 100644
index 000000000000..68a415aec545
--- /dev/null
+++ b/Documentation/security/launch-integrity/principles.rst
@@ -0,0 +1,320 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. Copyright © 2019-2023 Daniel P. Smith <[email protected]>
+
+=======================
+System Launch Integrity
+=======================
+
+:Author: Daniel P. Smith
+:Date: October 2023
+
+This document serves to establish a common understanding of what is system
+launch, the integrity concern for system launch, and why using a Root of Trust
+(RoT) from a Dynamic Launch may be desired. Throughout this document
+terminology from the Trusted Computing Group (TCG) and National Institute for
+Science and Technology (NIST) is used to ensure a vendor natural language is
+used to describe and reference security-related concepts.
+
+System Launch
+=============
+
+There is a tendency to only consider the classical power-on boot as the only
+means to launch an Operating System (OS) on a computer system, but in fact most
+modern processors support two methods to launch the system. To provide clarity
+a common definition of a system launch should be established. This definition
+is that a during a single power life cycle of a system, a System Launch
+consists of an initialization event, typically in hardware, that is followed by
+an executing software payload that takes the system from the initialized state
+to a running state. Driven by the Trusted Computing Group (TCG) architecture,
+modern processors are able to support two methods to launch a system, these two
+types of system launch are known as Static Launch and Dynamic Launch.
+
+Static Launch
+-------------
+
+Static launch is the system launch associated with the power cycle of the CPU.
+Thus, static launch refers to the classical power-on boot where the
+initialization event is the release of the CPU from reset and the system
+firmware is the software payload that brings the system up to a running state.
+Since static launch is the system launch associated with the beginning of the
+power lifecycle of a system, it is therefore a fixed, one-time system launch.
+It is because of this that static launch is referred to and thought of as being
+"static".
+
+Dynamic Launch
+--------------
+
+Modern CPUs architectures provides a mechanism to re-initialize the system to a
+"known good" state without requiring a power event. This re-initialization
+event is the event for a dynamic launch and is referred to as the Dynamic
+Launch Event (DLE). The DLE functions by accepting a software payload, referred
+to as the Dynamic Configuration Environment (DCE), that execution is handed to
+after the DLE is invoked. The DCE is responsible for bringing the system back
+to a running state. Since the dynamic launch is not tied to a power event like
+the static launch, this enables a dynamic launch to be initiated at any time
+and multiple times during a single power life cycle. This dynamism is the
+reasoning behind referring to this system launch as being dynamic.
+
+Because a dynamic launch can be conducted at any time during a single power
+life cycle, they are classified into one of two types, an early launch or a
+late launch.
+
+:Early Launch: When a dynamic launch is used as a transition from a static
+ launch chain to the final Operating System.
+
+:Late Launch: The usage of a dynamic launch by an executing Operating System to
+ transition to a “known good” state to perform one or more operations, e.g. to
+ launch into a new Operating System.
+
+System Integrity
+================
+
+A computer system can be considered a collection of mechanisms that work
+together to produce a result. The assurance that the mechanisms are functioning
+correctly and producing the expected result is the integrity of the system. To
+ensure a system's integrity there are a subset of these mechanisms, commonly
+referred to as security mechanisms, that are present to help ensure the system
+produces the expected result or at least detect the potential of an unexpected
+result may have happened. Since the security mechanisms are relied upon to
+ensue the integrity of the system, these mechanisms are trusted. Upon
+inspection these security mechanisms each have a set of properties and these
+properties can be evaluated to determine how susceptible a mechanism might be
+to failure. This assessment is referred to as the Strength of Mechanism and for
+trusted mechanism enables for the trustworthiness of that mechanism to be
+quantified.
+
+For software systems, there are two system states for which the integrity is
+critical, when the software is loaded into memory and when the software is
+executing on the hardware. Ensuring that the expected software is load into
+memory is referred to as load-time integrity while ensuring that the software
+executing is the expected software is the runtime integrity of that software.
+
+Load-time Integrity
+-------------------
+
+It is critical to understand what load-time integrity establishes about a
+system and what is assumed, i.e. what is being trusted. Load-time integrity is
+when a trusted entity, i.e. an entity with an assumed integrity, takes an
+action to assess an entity being loaded into memory before it is used. A
+variety of mechanisms may be used to conduct the assessment, each with
+different properties. A particular property is whether the mechanism creates an
+evidence of the assessment. Often either cryptographic signature checking or
+hashing are the common assessment operations used.
+
+A signature checking assessment functions by requiring a representation of the
+accepted authorities and uses those representations to assess if the entity has
+been signed by an accepted authority. The benefit to this process is that
+assessment process includes an adjudication of the assessment. The drawbacks
+are that 1) the adjudication is susceptible to tampering by the Trusted
+Computing Base (TCB), 2) there is no evidence to assert that an untampered
+adjudication was completed, and 3) the system must be an active participant in
+the key management infrastructure.
+
+A cryptographic hashing assessment does not adjudicate the assessment but
+instead, generates evidence of the assessment to be adjudicated independently.
+The benefits to this approach is that the assessment may be simple such that it
+may be implemented in an immutable mechanism, e.g. in hardware. Additionally,
+it is possible for the adjudication to be conducted where it cannot be tampered
+with by the TCB. The drawback is that a compromised environment will be allowed
+to execute until an adjudication can be completed.
+
+Ultimately, load-time integrity provides confidence that the correct entity was
+loaded and in the absence of a run-time integrity mechanism assumes, i.e.
+trusts, that the entity will never become corrupted.
+
+Runtime Integrity
+-----------------
+
+Runtime integrity in the general sense is when a trusted entity makes an
+assessment of an entity at any point in time during the assessed entity's
+execution. A more concrete explanation is the taking of an integrity assessment
+of an active process executing on the system at any point during the process'
+execution. Often the load-time integrity of an operating system's user-space,
+i.e. the operating environment, is confused to be the runtime integrity of the
+system, since it is an integrity assessment of the "runtime" software. The
+reality is that actual runtime integrity is a very difficult problem and thus
+not very many solutions are public and/or available. One example of a runtime
+integrity solution would be Johns Hopkins Advanced Physics Laboratory's (APL)
+Linux Kernel Integrity Module (LKIM).
+
+Trust Chains
+============
+
+Building upon the understanding of security mechanisms to establish load-time
+integrity of an entity, it is possible to chain together load-time integrity
+assessments to establish the integrity of the whole system. This process is
+known as transitive trust and provides the concept of building a chain of
+load-time integrity assessments, commonly referred to as a trust chain. These
+assessments may be used to adjudicate the load-time integrity of the whole
+system. This trust chain is started by a trusted entity that does the first
+assessment. This first entity is referred to as the Root of Trust(RoT) with the
+entities name being derived from the mechanism used for the assessment, i.e.
+RoT for Verification (RTV) and RoT for Measurement (RTM).
+
+A trust chain is itself a mechanism, specifically a mechanism of mechanisms,
+and therefore it too has a Strength of Mechanism. The factors that contribute
+to the strength of a trust chain are,
+
+ - The strength of the chain's RoT
+ - The strength of each member of the trust chain
+ - The length, i.e. the number of members, of the chain
+
+Therefore, to provide the strongest trust chains, they should start with a
+strong RoT and should consist of members being of low complexity and minimizing
+the number of members participating as possible. In a more colloquial sense, a
+trust chain is only as strong as its weakest link, thus more links increase the
+probability of a weak link.
+
+Dynamic Launch Components
+=========================
+
+The TCG architecture for dynamic launch is composed of a component series that
+are used to set up and then carry out the launch. These components work
+together to construct an RTM trust chain that is rooted in the dynamic launch
+and thus commonly referred to as the Dynamic Root of Trust for Measurement
+(DRTM) chain.
+
+What follows is a brief explanation of each component in execution order. A
+subset of these components are what establishes the dynamic launch's trust
+chain.
+
+Dynamic Configuration Environment Preamble
+------------------------------------------
+
+The Dynamic Configuration Environment (DCE) Preamble is responsible for setting
+up the system environment in preparation for a dynamic launch. The DCE Preamble
+is not a part of the DRTM trust chain.
+
+Dynamic Launch Event
+--------------------
+
+The dynamic launch event is the event, typically a CPU instruction, that
+triggers the system's dynamic launch mechanism to begin the launch. The dynamic
+launch mechanism is also the RoT for the DRTM trust chain.
+
+Dynamic Configuration Environment
+---------------------------------
+
+The dynamic launch mechanism may have resulted in a reset of a portion of the
+system. To bring the system back to an adequate state for system software, the
+dynamic launch will hand over control to the DCE. Prior to handing over this
+control, the dynamic launch, will measure the DCE. Once the DCE is complete it
+will proceed to measure and then execute the Dynamic Launch Measured
+Environment (DLME).
+
+Dynamic Launch Measured Environment
+-----------------------------------
+
+The DLME is the first system kernel to have control of the system, but may not
+be the last. Depending on the usage and configuration, the DLME may be the
+final/target operating system, or it may be a bootloader that will load the
+final/target operating system.
+
+Why DRTM
+========
+
+It is a fact that DRTM increases the load-time integrity of the system by
+providing a trust chain that has an immutable hardware RoT, uses a limited
+number of small, special purpose code to establish the trust chain that starts
+the target operating system. As mentioned in the Trust Chain section, these are
+the main three factors in driving up the strength of a trust chain. As has been
+seen with the BootHole exploit, which in fact did not affect the integrity of
+DRTM solutions, the sophistication of attacks targeting system launch is at an
+all-time high. There is no reason a system should not employ every integrity
+measure hardware makes available. This is the crux of a defense-in-depth
+approach to system security. In the past, the now closed SMI gap was often
+pointed to as invalidating DRTM, which in fact was nothing but a straw man
+argument. As has continued to be demonstrated, if/when SMM is corrupted it can
+always circumvent all load-time integrity, SRTM and DRTM, because it is a
+run-time integrity problem. Regardless, Intel and AMD have both deployed
+runtime integrity for SMI and SMM which is tied directly to DRTM such that this
+perceived deficiency is now non-existent, and the world is moving forward with
+an expectation that DRTM must be present.
+
+Glossary
+========
+
+.. glossary::
+ integrity
+ Guarding against improper information modification or destruction, and
+ includes ensuring information non-repudiation and authenticity.
+
+ - NIST CNSSI No. 4009 - https://www.cnss.gov/CNSS/issuances/Instructions.cfm
+
+ mechanism
+ A process or system that is used to produce a particular result.
+
+ - NIST Special Publication 800-160 (VOLUME 1 ) - https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-160v1.pdf
+
+ risk
+ A measure of the extent to which an entity is threatened by a potential
+ circumstance or event, and typically a function of: (i) the adverse impacts
+ that would arise if the circumstance or event occurs; and (ii) the
+ likelihood of occurrence.
+
+ - NIST SP 800-30 Rev. 1 - https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-30r1.pdf
+
+ security mechanism
+ A device or function designed to provide one or more security services
+ usually rated in terms of strength of service and assurance of the design.
+
+ - NIST CNSSI No. 4009 - https://www.cnss.gov/CNSS/issuances/Instructions.cfm
+
+ Strength of Mechanism
+ A scale for measuring the relative strength of a security mechanism
+
+ - NIST CNSSI No. 4009 - https://www.cnss.gov/CNSS/issuances/Instructions.cfm
+
+ transitive trust
+ Also known as "Inductive Trust", in this process a Root of Trust gives a
+ trustworthy description of a second group of functions. Based on this
+ description, an interested entity can determine the trust it is to place in
+ this second group of functions. If the interested entity determines that
+ the trust level of the second group of functions is acceptable, the trust
+ boundary is extended from the Root of Trust to include the second group of
+ functions. In this case, the process can be iterated. The second group of
+ functions can give a trustworthy description of the third group of
+ functions, etc. Transitive trust is used to provide a trustworthy
+ description of platform characteristics, and also to prove that
+ non-migratable keys are in fact non-migratable.
+
+ - TCG Glossary - https://trustedcomputinggroup.org/wp-content/uploads/TCG-Glossary-V1.1-Rev-1.0.pdf
+
+ trust
+ The confidence one element has in another that the second element will
+ behave as expected`
+
+ - NISTIR 8320A - https://nvlpubs.nist.gov/nistpubs/ir/2021/NIST.IR.8320A.pdf
+
+ trust anchor
+ An authoritative entity for which trust is assumed.
+
+ - NIST SP 800-57 Part 1 Rev. 5 - https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r5.pdf
+
+ trusted
+ An element that another element relies upon to fulfill critical
+ requirements on its behalf.
+
+ - NISTIR 8320A - https://nvlpubs.nist.gov/nistpubs/ir/2021/NIST.IR.8320A.pdf
+
+ trusted computing base (TCB)
+ Totality of protection mechanisms within a computer system, including
+ hardware, firmware, and software, the combination responsible for enforcing
+ a security policy.
+
+ - NIST CNSSI No. 4009 - https://www.cnss.gov/CNSS/issuances/Instructions.cfm
+
+ trusted computer system
+ A system that has the necessary security functions and assurance that the
+ security policy will be enforced and that can process a range of
+ information sensitivities (i.e. classified, controlled unclassified
+ information (CUI), or unclassified public information) simultaneously.
+
+ - NIST CNSSI No. 4009 - https://www.cnss.gov/CNSS/issuances/Instructions.cfm
+
+ trustworthiness
+ The attribute of a person or enterprise that provides confidence to others
+ of the qualifications, capabilities, and reliability of that entity to
+ perform specific tasks and fulfill assigned responsibilities.
+
+ - NIST CNSSI No. 4009 - https://www.cnss.gov/CNSS/issuances/Instructions.cfm
diff --git a/Documentation/security/launch-integrity/secure_launch_details.rst b/Documentation/security/launch-integrity/secure_launch_details.rst
new file mode 100644
index 000000000000..0031f556d510
--- /dev/null
+++ b/Documentation/security/launch-integrity/secure_launch_details.rst
@@ -0,0 +1,587 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. Copyright © 2019-2023 Daniel P. Smith <[email protected]>
+
+===================================
+Secure Launch Config and Interfaces
+===================================
+
+:Author: Daniel P. Smith
+:Date: October 2023
+
+Configuration
+=============
+
+The settings to enable Secure Launch using Kconfig are under::
+
+ "Processor type and features" --> "Secure Launch support"
+
+A kernel with this option enabled can still be booted using other supported
+methods.
+
+To reduce the Trusted Computing Base (TCB) of the MLE [1]_, the build
+configuration should be pared down as narrowly as one's use case allows. The
+fewer drivers (less active hardware) and features reduces the attack surface.
+As an example in the extreme, the MLE could only have local disk access with no
+other hardware supports, except optional network access for remote attestation.
+
+It is also desirable, if possible, to embed the initrd used with the MLE kernel
+image to reduce complexity.
+
+The following are a few important configuration necessities to always consider:
+
+KASLR Configuration
+-------------------
+
+Due to Secure Launch hardware implementation details and how KASLR functions,
+Secure Launch is not able to interoperate with KASLR at this time. Attempts to
+enable KASLR in a kernel started using Secure Launch may result in crashes and
+other instabilities at boot. Even in cases where Secure Launch and KASLR work
+together, it is still recommended that KASLR be disabled to avoid introducing
+security concerns with unprotected kernel memory.
+
+If possible, a kernel being used as an MLE should be built with KASLR disabled::
+
+ "Processor type and features" -->
+ "Build a relocatable kernel" -->
+ "Randomize the address of the kernel image (KASLR) [ ]"
+
+This action unsets the Kconfig value CONFIG_RANDOMIZE_BASE.
+
+If it is not possible to disable at build time, then it is recommended to force
+KASLR to be disabled using the kernel command line when doing a Secure Launch.
+The kernel parameter is as follows::
+
+ nokaslr
+
+.. note::
+ Should KASLR be made capable of reading/using only the protected page
+ regions set up by the memory protection mechanisms used by the hardware
+ DRTM capability, then it would become possible to use KASLR with Secure
+ Launch.
+
+IOMMU Configuration
+-------------------
+
+When doing a Secure Launch, the IOMMU should always be enabled and the drivers
+loaded. However, IOMMU passthrough mode should never be used. This leaves the
+MLE completely exposed to DMA after the PMR's [2]_ are disabled. The current
+default mode is to use IOMMU in lazy translated mode, but strict translated
+mode is the preferred IOMMU mode and this should be selected in the build
+configuration::
+
+ "Device Drivers" -->
+ "IOMMU Hardware Support" -->
+ "IOMMU default domain type" -->
+ "(X) Translated - Strict"
+
+In addition, the Intel IOMMU should be on by default. The following sets this as the
+default in the build configuration::
+
+ "Device Drivers" -->
+ "IOMMU Hardware Support" -->
+ "Support for Intel IOMMU using DMA Remapping Devices [*]"
+
+and::
+
+ "Device Drivers" -->
+ "IOMMU Hardware Support" -->
+ "Support for Intel IOMMU using DMA Remapping Devices [*]" -->
+ "Enable Intel DMA Remapping Devices by default [*]"
+
+It is recommended that no other command line options should be set to override
+the defaults above. If there is a desire to run an alternate configuration,
+then that configuration should be evaluated for what benefits are attempting to
+be gained against the risks for DMA attacks for which the kernel is likely
+going to be exposed.
+
+Secure Launch Resource Table
+============================
+
+The Secure Launch Resource Table (SLRT) is a platform-agnostic, standard format
+for providing information for the pre-launch environment and to pass
+information to the post-launch environment. The table is populated by one or
+more bootloaders in the boot chain and used by Secure Launch on how to set up
+the environment during post-launch. The details for the SLRT are documented
+in the TrenchBoot Secure Launch Specification [3]_.
+
+Intel TXT Interface
+===================
+
+The primary interfaces between the various components in TXT are the TXT MMIO
+registers and the TXT heap. The MMIO register banks are described in Appendix B
+of the TXT MLE [1]_ Development Guide.
+
+The TXT heap is described in Appendix C of the TXT MLE [1]_ Development
+Guide. Most of the TXT heap is predefined in the specification. The heap is
+initialized by firmware and the pre-launch environment and is subsequently used
+by the SINIT ACM. One section, called the OS to MLE Data Table, is reserved for
+software to define. This table is set up per the recommendation detailed in
+Appendix B of the TrenchBoot Secure Launch Specification::
+
+ /*
+ * Secure Launch defined OS/MLE TXT Heap table
+ */
+ struct txt_os_mle_data {
+ u32 version;
+ u32 boot_params_addr;
+ u64 slrt;
+ u64 txt_info;
+ u32 ap_wake_block;
+ u32 ap_wake_block_size;
+ u8 mle_scratch[64];
+ } __packed;
+
+Description of structure:
+
+===================== ========================================================================
+Field Use
+===================== ========================================================================
+version Structure version, current value 1
+boot_params_addr Physical base address of the Linux boot parameters
+slrt Physical address of the Secure Launch Resource Table
+txt_info Pointer into the SLRT for easily locating TXT specific table
+ap_wake_block Physical address of the block of memory for parking APs after a launch
+ap_wake_block_size Size of the AP wake block
+mle_scratch Scratch area used post-launch by the MLE kernel. Fields:
+
+ - SL_SCRATCH_AP_EBX area to share %ebx base pointer among CPUs
+ - SL_SCRATCH_AP_JMP_OFFSET offset to abs. ljmp fixup location for APs
+===================== ========================================================================
+
+Error Codes
+-----------
+
+The TXT specification defines the layout for TXT 32 bit error code values.
+The bit encodings indicate where the error originated (e.g. with the CPU,
+in the SINIT ACM, in software). The error is written to a sticky TXT
+register that persists across resets called TXT.ERRORCODE (see the TXT
+MLE Development Guide). The errors defined by the Secure Launch feature are
+those generated in the MLE software. They have the format::
+
+ 0xc0008XXX
+
+The low 12 bits are free for defining the following Secure Launch specific
+error codes.
+
+====== ================
+Name: SL_ERROR_GENERIC
+Value: 0xc0008001
+====== ================
+
+Description:
+
+Generic catch all error. Currently unused.
+
+====== =================
+Name: SL_ERROR_TPM_INIT
+Value: 0xc0008002
+====== =================
+
+Description:
+
+The Secure Launch code failed to get access to the TPM hardware interface.
+This is most likely due to misconfigured hardware or kernel. Ensure the TPM
+chip is enabled, and the kernel TPM support is built in (it should not be built
+as a module).
+
+====== ==========================
+Name: SL_ERROR_TPM_INVALID_LOG20
+Value: 0xc0008003
+====== ==========================
+
+Description:
+
+The Secure Launch code failed to find a valid event log descriptor for a
+version 2.0 TPM or the event log descriptor is malformed. Usually this
+indicates there are incompatible versions of the pre-launch environment and the
+MLE kernel. The pre-launch environment and the kernel share a structure in the
+TXT heap and if this structure (the OS-MLE table) is mismatched, this error is
+often seen. This TXT heap area is set up by the pre-launch environment, so the
+issue may originate there. It could also be the sign of an attempted attack.
+
+====== ===========================
+Name: SL_ERROR_TPM_LOGGING_FAILED
+Value: 0xc0008004
+====== ===========================
+
+Description:
+
+There was a failed attempt to write a TPM event to the event log early in the
+Secure Launch process. This is likely the result of a malformed TPM event log
+buffer. Formatting of the event log buffer information is done by the
+pre-launch environment, so the issue most likely originates there.
+
+====== ============================
+Name: SL_ERROR_REGION_STRADDLE_4GB
+Value: 0xc0008005
+====== ============================
+
+Description:
+
+During early validation, a buffer or region was found to straddle the 4GB
+boundary. Because of the way TXT does DMA memory protection, this is an unsafe
+configuration and is flagged as an error. This is most likely a configuration
+issue in the pre-launch environment. It could also be the sign of an attempted
+attack.
+
+====== ===================
+Name: SL_ERROR_TPM_EXTEND
+Value: 0xc0008006
+====== ===================
+
+Description:
+
+There was a failed attempt to extend a TPM PCR in the Secure Launch platform
+module. This is most likely to due to misconfigured hardware or kernel. Ensure
+the TPM chip is enabled, and the kernel TPM support is built in (it should not
+be built as a module).
+
+====== ======================
+Name: SL_ERROR_MTRR_INV_VCNT
+Value: 0xc0008007
+====== ======================
+
+Description:
+
+During early Secure Launch validation, an invalid variable MTRR count was
+found. The pre-launch environment passes a number of MSR values to the MLE to
+restore including the MTRRs. The values are restored by the Secure Launch early
+entry point code. After measuring the values supplied by the pre-launch
+environment, a discrepancy was found, validating the values. It could be the
+sign of an attempted attack.
+
+====== ==========================
+Name: SL_ERROR_MTRR_INV_DEF_TYPE
+Value: 0xc0008008
+====== ==========================
+
+Description:
+
+During early Secure Launch validation, an invalid default MTRR type was found.
+See SL_ERROR_MTRR_INV_VCNT for more details.
+
+====== ======================
+Name: SL_ERROR_MTRR_INV_BASE
+Value: 0xc0008009
+====== ======================
+
+Description:
+
+During early Secure Launch validation, an invalid variable MTRR base value was
+found. See SL_ERROR_MTRR_INV_VCNT for more details.
+
+====== ======================
+Name: SL_ERROR_MTRR_INV_MASK
+Value: 0xc000800a
+====== ======================
+
+Description:
+
+During early Secure Launch validation, an invalid variable MTRR mask value was
+found. See SL_ERROR_MTRR_INV_VCNT for more details.
+
+====== ========================
+Name: SL_ERROR_MSR_INV_MISC_EN
+Value: 0xc000800b
+====== ========================
+
+Description:
+
+During early Secure Launch validation, an invalid miscellaneous enable MSR
+value was found. See SL_ERROR_MTRR_INV_VCNT for more details.
+
+====== =========================
+Name: SL_ERROR_INV_AP_INTERRUPT
+Value: 0xc000800c
+====== =========================
+
+Description:
+
+The application processors (APs) wait to be woken up by the SMP initialization
+code. The only interrupt that they expect is an NMI; all other interrupts
+should be masked. If an AP gets some other interrupt other than an NMI, it will
+cause this error. This error is very unlikely to occur.
+
+====== =========================
+Name: SL_ERROR_INTEGER_OVERFLOW
+Value: 0xc000800d
+====== =========================
+
+Description:
+
+A buffer base and size passed to the MLE caused an integer overflow when
+added together. This is most likely a configuration issue in the pre-launch
+environment. It could also be the sign of an attempted attack.
+
+====== ==================
+Name: SL_ERROR_HEAP_WALK
+Value: 0xc000800e
+====== ==================
+
+Description:
+
+An error occurred in TXT heap walking code. The underlying issue is a failure to
+early_memremap() portions of the heap, most likely due to a resource shortage.
+
+====== =================
+Name: SL_ERROR_HEAP_MAP
+Value: 0xc000800f
+====== =================
+
+Description:
+
+This error is essentially the same as SL_ERROR_HEAP_WALK but occurred during the
+actual early_memremap() operation.
+
+====== =========================
+Name: SL_ERROR_REGION_ABOVE_4GB
+Value: 0xc0008010
+====== =========================
+
+Description:
+
+A memory region used by the MLE is above 4GB. In general this is not a problem
+because memory > 4Gb can be protected from DMA. There are certain buffers that
+should never be above 4Gb, and one of these caused the violation. This is most
+likely a configuration issue in the pre-launch environment. It could also be
+the sign of an attempted attack.
+
+====== ==========================
+Name: SL_ERROR_HEAP_INVALID_DMAR
+Value: 0xc0008011
+====== ==========================
+
+Description:
+
+The backup copy of the ACPI DMAR table which is supposed to be located in the
+TXT heap could not be found. This is due to a bug in the platform's ACM module
+or in firmware.
+
+====== =======================
+Name: SL_ERROR_HEAP_DMAR_SIZE
+Value: 0xc0008012
+====== =======================
+
+Description:
+
+The backup copy of the ACPI DMAR table in the TXT heap is to large to be stored
+for later usage. This error is very unlikely to occur since the area reserved
+for the copy is far larger than the DMAR should be.
+
+====== ======================
+Name: SL_ERROR_HEAP_DMAR_MAP
+Value: 0xc0008013
+====== ======================
+
+Description:
+
+The backup copy of the ACPI DMAR table in the TXT heap could not be mapped. The
+underlying issue is a failure to early_memremap() the DMAR table, most likely
+due to a resource shortage.
+
+====== ====================
+Name: SL_ERROR_HI_PMR_BASE
+Value: 0xc0008014
+====== ====================
+
+Description:
+
+On a system with more than 4G of RAM, the high PMR [2]_ base address should be
+set to 4G. This error is due to that not being the case. This PMR value is set
+by the pre-launch environment, so the issue most likely originates there. It
+could also be the sign of an attempted attack.
+
+====== ====================
+Name: SL_ERROR_HI_PMR_SIZE
+Value: 0xc0008015
+====== ====================
+
+Description:
+
+On a system with more than 4G of RAM, the high PMR [2]_ size should be set to
+cover all RAM > 4G. This error is due to that not being the case. This PMR
+value is set by the pre-launch environment, so the issue most likely originates
+there. It could also be the sign of an attempted attack.
+
+====== ====================
+Name: SL_ERROR_LO_PMR_BASE
+Value: 0xc0008016
+====== ====================
+
+Description:
+
+The low PMR [2]_ base should always be set to address zero. This error is due
+to that not being the case. This PMR value is set by the pre-launch environment
+so the issue most likely originates there. It could also be the sign of an
+attempted attack.
+
+====== ====================
+Name: SL_ERROR_LO_PMR_MLE
+Value: 0xc0008017
+====== ====================
+
+Description:
+
+This error indicates the MLE image is not covered by the low PMR [2]_ range.
+The PMR values are set by the pre-launch environment, so the issue most likely
+originates there. It could also be the sign of an attempted attack.
+
+====== =======================
+Name: SL_ERROR_INITRD_TOO_BIG
+Value: 0xc0008018
+====== =======================
+
+Description:
+
+The external initrd provided is larger than 4Gb. This is not a valid
+configuration for a Secure Launch due to managing DMA protection.
+
+====== =========================
+Name: SL_ERROR_HEAP_ZERO_OFFSET
+Value: 0xc0008019
+====== =========================
+
+Description:
+
+During a TXT heap walk, an invalid/zero next table offset value was found. This
+indicates the TXT heap is malformed. The TXT heap is initialized by the
+pre-launch environment, so the issue most likely originates there. It could
+also be a sign of an attempted attack. In addition, ACM is also responsible for
+manipulating parts of the TXT heap, so the issue could be due to a bug in the
+platform's ACM module.
+
+====== =============================
+Name: SL_ERROR_WAKE_BLOCK_TOO_SMALL
+Value: 0xc000801a
+====== =============================
+
+Description:
+
+The AP wake block buffer passed to the MLE via the OS-MLE TXT heap table is not
+large enough. This value is set by the pre-launch environment, so the issue
+most likely originates there. It also could be the sign of an attempted attack.
+
+====== ===========================
+Name: SL_ERROR_MLE_BUFFER_OVERLAP
+Value: 0xc000801b
+====== ===========================
+
+Description:
+
+One of the buffers passed to the MLE via the OS-MLE TXT heap table overlaps
+with the MLE image in memory. This value is set by the pre-launch environment
+so the issue most likely originates there. It could also be the sign of an
+attempted attack.
+
+====== ==========================
+Name: SL_ERROR_BUFFER_BEYOND_PMR
+Value: 0xc000801c
+====== ==========================
+
+Description:
+
+One of the buffers passed to the MLE via the OS-MLE TXT heap table is not
+protected by a PMR. This value is set by the pre-launch environment, so the
+issue most likely originates there. It could also be the sign of an attempted
+attack.
+
+====== =============================
+Name: SL_ERROR_OS_SINIT_BAD_VERSION
+Value: 0xc000801d
+====== =============================
+
+Description:
+
+The version of the OS-SINIT TXT heap table is bad. It must be 6 or greater.
+This value is set by the pre-launch environment, so the issue most likely
+originates there. It could also be the sign of an attempted attack. It is also
+possible though very unlikely that the platform is so old that the ACM being
+used requires an unsupported version.
+
+====== =====================
+Name: SL_ERROR_EVENTLOG_MAP
+Value: 0xc000801e
+====== =====================
+
+Description:
+
+An error occurred in the Secure Launch module while mapping the TPM event log.
+The underlying issue is memremap() failure, most likely due to a resource
+shortage.
+
+====== ========================
+Name: SL_ERROR_TPM_NUMBER_ALGS
+Value: 0xc000801f
+====== ========================
+
+Description:
+
+The TPM 2.0 event log reports an unsupported number of hashing algorithms.
+Secure launch currently only supports a maximum of two: SHA1 and SHA256.
+
+====== ===========================
+Name: SL_ERROR_TPM_UNKNOWN_DIGEST
+Value: 0xc0008020
+====== ===========================
+
+Description:
+
+The TPM 2.0 event log reports an unsupported hashing algorithm. Secure launch
+currently only supports two algorithms: SHA1 and SHA256.
+
+====== ==========================
+Name: SL_ERROR_TPM_INVALID_EVENT
+Value: 0xc0008021
+====== ==========================
+
+Description:
+
+An invalid/malformed event was found in the TPM event log while reading it.
+Since only trusted entities are supposed to be writing the event log, this
+would indicate either a bug or a possible attack.
+
+====== =====================
+Name: SL_ERROR_INVALID_SLRT
+Value: 0xc0008022
+====== =====================
+
+Description:
+
+The Secure Launch Resource Table is invalid or malformed and is unusable. This
+implies the pre-launch code did not properly set up the SLRT.
+
+====== ===========================
+Name: SL_ERROR_SLRT_MISSING_ENTRY
+Value: 0xc0008023
+====== ===========================
+
+Description:
+
+The Secure Launch Resource Table is missing a required entry within it. This
+implies the pre-launch code did not properly set up the SLRT.
+
+====== =================
+Name: SL_ERROR_SLRT_MAP
+Value: 0xc0008024
+====== =================
+
+Description:
+
+An error occurred in the Secure Launch module while mapping the Secure Launch
+Resource table. The underlying issue is memremap() failure, most likely due to
+a resource shortage.
+
+.. [1]
+ MLE: Measured Launch Environment is the binary runtime that is measured and
+ then run by the TXT SINIT ACM. The TXT MLE Development Guide describes the
+ requirements for the MLE in detail.
+
+.. [2]
+ PMR: Intel VTd has a feature in the IOMMU called Protected Memory Registers.
+ There are two of these registers and they allow all DMA to be blocked
+ to large areas of memory. The low PMR can cover all memory below 4Gb on 2Mb
+ boundaries. The high PMR can cover all RAM on the system, again on 2Mb
+ boundaries. This feature is used during a Secure Launch by TXT.
+
+.. [3]
+ Secure Launch Specification: https://trenchboot.org/specifications/Secure_Launch/
diff --git a/Documentation/security/launch-integrity/secure_launch_overview.rst b/Documentation/security/launch-integrity/secure_launch_overview.rst
new file mode 100644
index 000000000000..fa3e08780673
--- /dev/null
+++ b/Documentation/security/launch-integrity/secure_launch_overview.rst
@@ -0,0 +1,227 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. Copyright © 2019-2023 Daniel P. Smith <[email protected]>
+
+======================
+Secure Launch Overview
+======================
+
+:Author: Daniel P. Smith
+:Date: October 2023
+
+Overview
+========
+
+Prior to the start of the TrenchBoot project, the only active Open Source
+project supporting dynamic launch was Intel's tboot project to support their
+implementation of dynamic launch known as Intel Trusted eXecution Technology
+(TXT). The approach taken by tboot was to provide an exokernel that could
+handle the launch protocol implemented by Intel's special loader, the SINIT
+Authenticated Code Module (ACM [2]_) and remained in memory to manage the SMX
+CPU mode that a dynamic launch would put a system. While it is not precluded
+from being used for doing a late launch, tboot's primary use case was to be
+used as an early launch solution. As a result, the TrenchBoot project started
+the development of Secure Launch kernel feature to provide a more generalized
+approach. The focus of the effort is twofold, the first is to make the Linux
+kernel directly aware of the launch protocol used by Intel, AMD/Hygon, Arm, and
+potentially OpenPOWER. The second is to make the Linux kernel be able to
+initiate a dynamic launch. It is through this approach that the Secure Launch
+kernel feature creates a basis for the Linux kernel to be used in a variety of
+dynamic launch use cases.
+
+.. note::
+ A quick note on terminology. The larger open source project itself is
+ called TrenchBoot, which is hosted on GitHub (links below). The kernel
+ feature enabling the use of the x86 technology is referred to as "Secure
+ Launch" within the kernel code.
+
+Goals
+=====
+
+The first use case that the TrenchBoot project focused on was the ability for
+the Linux kernel to be started by a dynamic launch, in particular as part of an
+early launch sequence. In this case, the dynamic launch will be initiated by
+any bootloader with associated support added to it, for example the first
+targeted bootloader in this case was GRUB2. An integral part of establishing a
+measurement-based launch integrity involves measuring everything that is
+intended to be executed (kernel image, initrd, etc.) and everything that will
+configure that kernel to execute (command line, boot params, etc.). Then
+storing those measurements in a protected manner. Both the Intel and AMD
+dynamic launch implementations leverage the Trusted Platform Module (TPM) to
+store those measurements. The TPM itself has been designed such that a dynamic
+launch unlocks a specific set of Platform Configuration Registers (PCR) for
+holding measurement taken during the dynamic launch. These are referred to as
+the DRTM PCRs, PCRs 17-22. Further details on this process can be found in the
+documentation for the GETSEC instruction provided by Intel's TXT and the SKINIT
+instruction provided by AMD's AMD-V. The documentation on these technologies
+can be readily found online; see the `Resources`_ section below for references.
+
+.. note::
+ Currently, only Intel TXT is supported in this first release of the Secure
+ Launch feature. AMD/Hygon SKINIT and Arm support will be added in a
+ subsequent release.
+
+To enable the kernel to be launched by GETSEC a stub, the Secure Launch stub,
+must be built into the setup section of the compressed kernel to handle the
+specific state that the dynamic launch process leaves the BSP. Also, the Secure
+Launch stub must measure everything that is going to be used as early as
+possible. This stub code and subsequent code must also deal with the specific
+state that the dynamic launch leaves the APs as well.
+
+Design Decisions
+================
+
+A number of design decisions were made during the development of the Secure
+Launch feature. The two primary guiding decisions were:
+
+ - Keeping the Secure Launch code as separate from the rest of the kernel
+ as possible.
+ - Modifying the existing boot path of the kernel as little as possible.
+
+The following illustrate how the implementation followed these design
+decisions:
+
+ - All the entry point code necessary to properly configure the system post
+ launch is found in st_stub.S in the compressed kernel image. This code
+ validates the state of the system, restores necessary system operating
+ configurations and properly handles post launch CPU states.
+ - After the sl_stub.S is complete, it jumps directly to the unmodified
+ startup_32 kernel entry point.
+ - A single call is made to a function sl_main() prior to the main kernel
+ decompression step. This code performs further validation and takes the
+ needed DRTM measurements.
+ - After the call to sl_main(), the main kernel is decompressed and boots as
+ it normally would.
+ - Final setup for the Secure Launch kernel is done in a separate Secure
+ Launch module that is loaded via a late initcall. This code is responsible
+ for extending the measurements taken earlier into the TPM DRTM PCRs and
+ setting up the securityfs interface to allow access to the TPM event log and
+ public TXT registers.
+ - On the reboot and kexec paths, calls are made to a function to finalize the
+ state of the Secure Launch kernel.
+
+The one place where Secure Launch code is mixed directly in with kernel code is
+in the SMP boot code. This is due to the unique state that the dynamic launch
+leaves the APs in. On Intel, this involves using a method other than the
+standard INIT-SIPI sequence.
+
+A final note is that originally the extending of the PCRs was completed in the
+Secure Launch stub when the measurements were taken. An alternative solution
+had to be implemented due to the TPM maintainers objecting to the PCR
+extensions being done with a minimal interface to the TPM that was an
+independent implementation of the mainline kernel driver. Since the mainline
+driver relies heavily on kernel interfaces not available in the compressed
+kernel, it was not possible to reuse the mainline TPM driver. This resulted in
+the decision to move the extension operations to the Secure Launch module in
+the mainline kernel, where the TPM driver would be available.
+
+Basic Boot Flow
+===============
+
+Outlined here is a summary of the boot flow for Secure Launch. A more detailed
+review of Secure Launch process can be found in the Secure Launch
+Specification, a link is located in the `Resources`_ section.
+
+Pre-launch: *Phase where the environment is prepared and configured to initiate
+the secure launch by the boot chain.*
+
+ - The SLRT is initialized and dl_stub is placed in memory.
+ - Load the kernel, initrd and ACM [2]_ into memory.
+ - Set up the TXT heap and page tables describing the MLE [1]_ per the
+ specification.
+ - If non-UEFI platform, dl_stub is called.
+ - If UEFI platforms, SLRT registered with UEFI and efi-stub called.
+ - Upon completion, efi-stub will call EBS followed by dl_stub.
+ - The dl_stub will prepare the CPU and the TPM for the launch.
+ - The secure launch is then initiated with the GETSET[SENTER] instruction.
+
+Post-launch: *Phase where control is passed from the ACM to the MLE and the secure
+kernel begins execution.*
+
+ - Entry from the dynamic launch jumps to the SL stub.
+ - SL stub fixes up the world on the BSP.
+ - For TXT, SL stub wakes the APs, fixes up their worlds.
+ - For TXT, APs are left halted using MONITOR/MWAIT intructions.
+ - SL stub jumps to startup_32.
+ - SL main does validation of buffers and memory locations. It sets
+ the boot parameter loadflag value SLAUNCH_FLAG to inform the main
+ kernel that a Secure Launch was done.
+ - SL main locates the TPM event log and writes the measurements of
+ configuration and module information into it.
+ - Kernel boot proceeds normally from this point.
+ - During early setup, slaunch_setup() runs to finish some validation
+ and setup tasks.
+ - The SMP bring up code is modified to wake the waiting APs via the monitor
+ address.
+ - APs vector to rmpiggy and start up normally from that point.
+ - SL platform module is registered as a late initcall module. It reads
+ the TPM event log and extends the measurements taken into the TPM PCRs.
+ - SL platform module initializes the securityfs interface to allow
+ access to the TPM event log and TXT public registers.
+ - Kernel boot finishes booting normally
+ - SEXIT support to leave SMX mode is present on the kexec path and
+ the various reboot paths (poweroff, reset, halt).
+
+PCR Usage
+=========
+
+The TCG DRTM architecture there are three PCRs defined for usage, PCR.Details
+(PCR17), PCR.Authorities (PCR18), and PCR.DLME_Authority (PCR19). For a deeper
+understanding of Detail and Authorities it is recommended to review the TCG
+DRTM architecture.
+
+To determine PCR usage, Linux Secure Launch follows the TrenchBoot Secure
+Launch Specification of using a measurement policy stored in the SLRT. The
+policy details what should be measured and the PCR in which to store the
+measurement. The measurement policy provides the ability to select the
+PCR.DLME_Detail (PCR20) PCR as the location for the DRTM components measured by
+the kernel, e.g. external initrd image. This can then be combined with storing
+the user authority in the PCR.DLME_Authority PCR to seal/attest to different
+variations of platform details/authorities and user details/authorities. An
+example of how this can be achieved was presented in the FOSDEM - 2021 talk
+"Secure Upgrades with DRTM".
+
+Resources
+=========
+
+The TrenchBoot project:
+
+https://trenchboot.org
+
+Secure Launch Specification:
+
+https://trenchboot.org/specifications/Secure_Launch/
+
+Trusted Computing Group's D-RTM Architecture:
+
+https://trustedcomputinggroup.org/wp-content/uploads/TCG_D-RTM_Architecture_v1-0_Published_06172013.pdf
+
+TXT documentation in the Intel TXT MLE Development Guide:
+
+https://www.intel.com/content/dam/www/public/us/en/documents/guides/intel-txt-software-development-guide.pdf
+
+TXT instructions documentation in the Intel SDM Instruction Set volume:
+
+https://software.intel.com/en-us/articles/intel-sdm
+
+AMD SKINIT documentation in the System Programming manual:
+
+https://www.amd.com/system/files/TechDocs/24593.pdf
+
+GRUB Secure Launch support:
+
+https://github.com/TrenchBoot/grub/tree/grub-sl-fc-38-dlstub
+
+FOSDEM 2021: Secure Upgrades with DRTM
+
+https://archive.fosdem.org/2021/schedule/event/firmware_suwd/
+
+.. [1]
+ MLE: Measured Launch Environment is the binary runtime that is measured and
+ then run by the TXT SINIT ACM. The TXT MLE Development Guide describes the
+ requirements for the MLE in detail.
+
+.. [2]
+ ACM: Intel's Authenticated Code Module. This is the 32b bit binary blob that
+ is run securely by the GETSEC[SENTER] during a measured launch. It is described
+ in the Intel documentation on TXT and versions for various chipsets are
+ signed and distributed by Intel.
--
2.39.3

2024-05-31 01:34:39

by Ross Philipson

Subject: [PATCH v9 07/19] x86: Add early SHA-256 support for Secure Launch early measurements

From: "Daniel P. Smith" <[email protected]>

The SHA-256 algorithm is necessary to measure configuration information into
the TPM as early as possible before using the values. This implementation
uses the established approach of #including the SHA-256 libraries directly in
the code since the compressed kernel is not uncompressed at this point.

Signed-off-by: Daniel P. Smith <[email protected]>
Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/boot/compressed/Makefile | 2 +-
arch/x86/boot/compressed/early_sha256.c | 6 ++++++
2 files changed, 7 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/boot/compressed/early_sha256.c

diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 3307ebef4e1b..9189a0e28686 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -118,7 +118,7 @@ vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_mixed.o
vmlinux-objs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a

-vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o
+vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o

$(obj)/vmlinux: $(vmlinux-objs-y) FORCE
$(call if_changed,ld)
diff --git a/arch/x86/boot/compressed/early_sha256.c b/arch/x86/boot/compressed/early_sha256.c
new file mode 100644
index 000000000000..293742a90ddc
--- /dev/null
+++ b/arch/x86/boot/compressed/early_sha256.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024 Apertus Solutions, LLC
+ */
+
+#include "../../../../lib/crypto/sha256.c"
--
2.39.3

2024-05-31 01:35:33

by Ross Philipson

Subject: [PATCH v9 10/19] x86: Secure Launch SMP bringup support

On Intel, the APs are left in a well documented state after TXT performs
the late launch. Specifically they cannot have #INIT asserted on them so
a standard startup via INIT/SIPI/SIPI cannot be performed. Instead the
early SL stub code uses MONITOR and MWAIT to park the APs. The realmode/init.c
code updates the jump address for the waiting APs with the location of the
Secure Launch entry point in the RM piggy after it is loaded and fixed up.
As the APs are woken up by writing the monitor, the APs jump to the Secure
Launch entry point in the RM piggy which mimics what the real mode code would
do then jumps to the standard RM piggy protected mode entry point.

Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/include/asm/realmode.h | 3 ++
arch/x86/kernel/smpboot.c | 58 +++++++++++++++++++++++++++-
arch/x86/realmode/init.c | 3 ++
arch/x86/realmode/rm/header.S | 3 ++
arch/x86/realmode/rm/trampoline_64.S | 32 +++++++++++++++
5 files changed, 97 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h
index 87e5482acd0d..339b48e2543d 100644
--- a/arch/x86/include/asm/realmode.h
+++ b/arch/x86/include/asm/realmode.h
@@ -38,6 +38,9 @@ struct real_mode_header {
#ifdef CONFIG_X86_64
u32 machine_real_restart_seg;
#endif
+#ifdef CONFIG_SECURE_LAUNCH
+ u32 sl_trampoline_start32;
+#endif
};

/* This must match data at realmode/rm/trampoline_{32,64}.S */
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 0c35207320cb..adb521221d6c 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -60,6 +60,7 @@
#include <linux/stackprotector.h>
#include <linux/cpuhotplug.h>
#include <linux/mc146818rtc.h>
+#include <linux/slaunch.h>

#include <asm/acpi.h>
#include <asm/cacheinfo.h>
@@ -868,6 +869,56 @@ int common_cpu_up(unsigned int cpu, struct task_struct *idle)
return 0;
}

+#ifdef CONFIG_SECURE_LAUNCH
+
+static bool slaunch_is_txt_launch(void)
+{
+ if ((slaunch_get_flags() & (SL_FLAG_ACTIVE|SL_FLAG_ARCH_TXT)) ==
+ (SL_FLAG_ACTIVE | SL_FLAG_ARCH_TXT))
+ return true;
+
+ return false;
+}
+
+/*
+ * TXT AP startup is quite different than normal. The APs cannot have #INIT
+ * asserted on them or receive SIPIs. The early Secure Launch code has parked
+ * the APs using monitor/mwait. This will wake the APs by writing the monitor
+ * and have them jump to the protected mode code in the rmpiggy where the rest
+ * of the SMP boot of the AP will proceed normally.
+ */
+static void slaunch_wakeup_cpu_from_txt(int cpu, int apicid)
+{
+ struct sl_ap_wake_info *ap_wake_info;
+ struct sl_ap_stack_and_monitor *stack_monitor = NULL;
+
+ ap_wake_info = slaunch_get_ap_wake_info();
+
+ stack_monitor = (struct sl_ap_stack_and_monitor *)__va(ap_wake_info->ap_wake_block +
+ ap_wake_info->ap_stacks_offset);
+
+ for (unsigned int i = TXT_MAX_CPUS - 1; i >= 0; i--) {
+ if (stack_monitor[i].apicid == apicid) {
+ /* Write the monitor */
+ stack_monitor[i].monitor = 1;
+ break;
+ }
+ }
+}
+
+#else
+
+static inline bool slaunch_is_txt_launch(void)
+{
+ return false;
+}
+
+static inline void slaunch_wakeup_cpu_from_txt(int cpu, int apicid)
+{
+}
+
+#endif /* !CONFIG_SECURE_LAUNCH */
+
/*
* NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
* (ie clustered apic addressing mode), this is a LOGICAL apic ID.
@@ -877,7 +928,7 @@ int common_cpu_up(unsigned int cpu, struct task_struct *idle)
static int do_boot_cpu(u32 apicid, int cpu, struct task_struct *idle)
{
unsigned long start_ip = real_mode_header->trampoline_start;
- int ret;
+ int ret = 0;

#ifdef CONFIG_X86_64
/* If 64-bit wakeup method exists, use the 64-bit mode trampoline IP */
@@ -922,12 +973,15 @@ static int do_boot_cpu(u32 apicid, int cpu, struct task_struct *idle)

/*
* Wake up a CPU in difference cases:
+ * - Intel TXT DRTM launch uses its own method to wake the APs
* - Use a method from the APIC driver if one defined, with wakeup
* straight to 64-bit mode preferred over wakeup to RM.
* Otherwise,
* - Use an INIT boot APIC message
*/
- if (apic->wakeup_secondary_cpu_64)
+ if (slaunch_is_txt_launch())
+ slaunch_wakeup_cpu_from_txt(cpu, apicid);
+ else if (apic->wakeup_secondary_cpu_64)
ret = apic->wakeup_secondary_cpu_64(apicid, start_ip);
else if (apic->wakeup_secondary_cpu)
ret = apic->wakeup_secondary_cpu(apicid, start_ip);
diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
index f9bc444a3064..d95776cb30d3 100644
--- a/arch/x86/realmode/init.c
+++ b/arch/x86/realmode/init.c
@@ -4,6 +4,7 @@
#include <linux/memblock.h>
#include <linux/cc_platform.h>
#include <linux/pgtable.h>
+#include <linux/slaunch.h>

#include <asm/set_memory.h>
#include <asm/realmode.h>
@@ -210,6 +211,8 @@ void __init init_real_mode(void)

setup_real_mode();
set_real_mode_permissions();
+
+ slaunch_fixup_jump_vector();
}

static int __init do_init_real_mode(void)
diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S
index 2eb62be6d256..3b5cbcbbfc90 100644
--- a/arch/x86/realmode/rm/header.S
+++ b/arch/x86/realmode/rm/header.S
@@ -37,6 +37,9 @@ SYM_DATA_START(real_mode_header)
#ifdef CONFIG_X86_64
.long __KERNEL32_CS
#endif
+#ifdef CONFIG_SECURE_LAUNCH
+ .long pa_sl_trampoline_start32
+#endif
SYM_DATA_END(real_mode_header)

/* End signature, used to verify integrity */
diff --git a/arch/x86/realmode/rm/trampoline_64.S b/arch/x86/realmode/rm/trampoline_64.S
index 14d9c7daf90f..b0ce6205d7ea 100644
--- a/arch/x86/realmode/rm/trampoline_64.S
+++ b/arch/x86/realmode/rm/trampoline_64.S
@@ -122,6 +122,38 @@ SYM_CODE_END(sev_es_trampoline_start)

.section ".text32","ax"
.code32
+#ifdef CONFIG_SECURE_LAUNCH
+ .balign 4
+SYM_CODE_START(sl_trampoline_start32)
+ /*
+ * The early secure launch stub AP wakeup code has taken care of all
+ * the vagaries of launching out of TXT. This bit just mimics what the
+ * 16b entry code does and jumps off to the real startup_32.
+ */
+ cli
+ wbinvd
+
+ /*
+ * The %ebx provided is not terribly useful since it is the physical
+ * address of tb_trampoline_start and not the base of the image.
+ * Use pa_real_mode_base, which is fixed up, to get a run time
+ * base register to use for offsets to location that do not have
+ * pa_ symbols.
+ */
+ movl $pa_real_mode_base, %ebx
+
+ LOCK_AND_LOAD_REALMODE_ESP lock_pa=1
+
+ lgdt tr_gdt(%ebx)
+ lidt tr_idt(%ebx)
+
+ movw $__KERNEL_DS, %dx # Data segment descriptor
+
+ /* Jump to where the 16b code would have jumped */
+ ljmpl $__KERNEL32_CS, $pa_startup_32
+SYM_CODE_END(sl_trampoline_start32)
+#endif
+
.balign 4
SYM_CODE_START(startup_32)
movl %edx, %ss
--
2.39.3

2024-05-31 01:35:41

by Ross Philipson

Subject: [PATCH v9 12/19] reboot: Secure Launch SEXIT support on reboot paths

If the MLE kernel is being powered off, rebooted or halted,
then SEXIT must be called. Note that the SEXIT GETSEC leaf
can only be called after a machine_shutdown() has been done on
these paths. The machine_shutdown() is not called on a few paths
like when poweroff action does not have a poweroff callback (into
ACPI code) or when an emergency reset is done. In these cases,
just the TXT registers are finalized but SEXIT is skipped.

Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/kernel/reboot.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index f3130f762784..66060fdb0822 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -12,6 +12,7 @@
#include <linux/delay.h>
#include <linux/objtool.h>
#include <linux/pgtable.h>
+#include <linux/slaunch.h>
#include <acpi/reboot.h>
#include <asm/io.h>
#include <asm/apic.h>
@@ -766,6 +767,7 @@ static void native_machine_restart(char *__unused)

if (!reboot_force)
machine_shutdown();
+ slaunch_finalize(!reboot_force);
__machine_emergency_restart(0);
}

@@ -776,6 +778,9 @@ static void native_machine_halt(void)

tboot_shutdown(TB_SHUTDOWN_HALT);

+ /* SEXIT done after machine_shutdown() to meet TXT requirements */
+ slaunch_finalize(1);
+
stop_this_cpu(NULL);
}

@@ -784,8 +789,12 @@ static void native_machine_power_off(void)
if (kernel_can_power_off()) {
if (!reboot_force)
machine_shutdown();
+ slaunch_finalize(!reboot_force);
do_kernel_power_off();
+ } else {
+ slaunch_finalize(0);
}
+
/* A fallback in case there is no PM info available */
tboot_shutdown(TB_SHUTDOWN_HALT);
}
@@ -813,6 +822,7 @@ void machine_shutdown(void)

void machine_emergency_restart(void)
{
+ slaunch_finalize(0);
__machine_emergency_restart(1);
}

--
2.39.3

2024-05-31 01:35:48

by Ross Philipson

Subject: [PATCH v9 17/19] tpm: Add sysfs interface to allow setting and querying the preferred locality

Expose a sysfs interface to allow user mode to set and query the preferred
locality for the TPM chip.

Signed-off-by: Ross Philipson <[email protected]>
---
drivers/char/tpm/tpm-sysfs.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 94231f052ea7..5f4a966a4599 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -324,6 +324,34 @@ static ssize_t null_name_show(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR_RO(null_name);
#endif

+static ssize_t preferred_locality_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct tpm_chip *chip = to_tpm_chip(dev);
+
+ return sprintf(buf, "%d\n", chip->pref_locality);
+}
+
+static ssize_t preferred_locality_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct tpm_chip *chip = to_tpm_chip(dev);
+ unsigned int locality;
+
+ if (kstrtouint(buf, 0, &locality))
+ return -ERANGE;
+
+ if (locality >= TPM_MAX_LOCALITY)
+ return -ERANGE;
+
+ if (tpm_chip_preferred_locality(chip, (int)locality))
+ return count;
+ else
+ return 0;
+}
+
+static DEVICE_ATTR_RW(preferred_locality);
+
static struct attribute *tpm1_dev_attrs[] = {
&dev_attr_pubek.attr,
&dev_attr_pcrs.attr,
@@ -336,6 +364,7 @@ static struct attribute *tpm1_dev_attrs[] = {
&dev_attr_durations.attr,
&dev_attr_timeouts.attr,
&dev_attr_tpm_version_major.attr,
+ &dev_attr_preferred_locality.attr,
NULL,
};

@@ -344,6 +373,7 @@ static struct attribute *tpm2_dev_attrs[] = {
#ifdef CONFIG_TCG_TPM2_HMAC
&dev_attr_null_name.attr,
#endif
+ &dev_attr_preferred_locality.attr,
NULL
};

--
2.39.3

2024-05-31 01:36:24

by Ross Philipson

Subject: [PATCH v9 09/19] x86: Secure Launch kernel late boot stub

The routine slaunch_setup is called out of the x86 specific setup_arch()
routine during early kernel boot. After determining what platform is
present, various operations specific to that platform occur. This
includes finalizing setting for the platform late launch and verifying
that memory protections are in place.

For TXT, this code also reserves the original compressed kernel setup
area where the APs were left looping so that this memory cannot be used.

Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/kernel/Makefile | 1 +
arch/x86/kernel/setup.c | 3 +
arch/x86/kernel/slaunch.c | 525 +++++++++++++++++++++++++++++++++++++
drivers/iommu/intel/dmar.c | 4 +
4 files changed, 533 insertions(+)
create mode 100644 arch/x86/kernel/slaunch.c

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 5d128167e2e2..b35ca99ab0a0 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -76,6 +76,7 @@ obj-$(CONFIG_X86_32) += tls.o
obj-$(CONFIG_IA32_EMULATION) += tls.o
obj-y += step.o
obj-$(CONFIG_INTEL_TXT) += tboot.o
+obj-$(CONFIG_SECURE_LAUNCH) += slaunch.o
obj-$(CONFIG_ISA_DMA_API) += i8237.o
obj-y += stacktrace.o
obj-y += cpu/
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 55a1fc332e20..31d1e6b9bd36 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -21,6 +21,7 @@
#include <linux/root_dev.h>
#include <linux/hugetlb.h>
#include <linux/tboot.h>
+#include <linux/slaunch.h>
#include <linux/usb/xhci-dbgp.h>
#include <linux/static_call.h>
#include <linux/swiotlb.h>
@@ -936,6 +937,8 @@ void __init setup_arch(char **cmdline_p)
early_gart_iommu_check();
#endif

+ slaunch_setup_txt();
+
/*
* partially used pages are not usable - thus
* we are rounding upwards:
diff --git a/arch/x86/kernel/slaunch.c b/arch/x86/kernel/slaunch.c
new file mode 100644
index 000000000000..48c9ca78e241
--- /dev/null
+++ b/arch/x86/kernel/slaunch.c
@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Secure Launch late validation/setup and finalization support.
+ *
+ * Copyright (c) 2024, Oracle and/or its affiliates.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/linkage.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/security.h>
+#include <linux/memblock.h>
+#include <asm/segment.h>
+#include <asm/sections.h>
+#include <asm/tlbflush.h>
+#include <asm/e820/api.h>
+#include <asm/setup.h>
+#include <asm/realmode.h>
+#include <linux/slr_table.h>
+#include <linux/slaunch.h>
+
+static u32 sl_flags __ro_after_init;
+static struct sl_ap_wake_info ap_wake_info __ro_after_init;
+static u64 evtlog_addr __ro_after_init;
+static u32 evtlog_size __ro_after_init;
+static u64 vtd_pmr_lo_size __ro_after_init;
+
+/* This should be plenty of room */
+static u8 txt_dmar[PAGE_SIZE] __aligned(16);
+
+/*
+ * Get the Secure Launch flags that indicate what kind of launch is being done.
+ * E.g. a TXT launch is in progress or no Secure Launch is happening.
+ */
+u32 slaunch_get_flags(void)
+{
+ return sl_flags;
+}
+
+/*
+ * Return the AP wakeup information used in the SMP boot code to start up
+ * the APs that are parked using MONITOR/MWAIT.
+ */
+struct sl_ap_wake_info *slaunch_get_ap_wake_info(void)
+{
+ return &ap_wake_info;
+}
+
+/*
+ * On Intel platforms, TXT passes a safe copy of the DMAR ACPI table to the
+ * DRTM. The DRTM is supposed to use this instead of the one found in the
+ * ACPI tables.
+ */
+struct acpi_table_header *slaunch_get_dmar_table(struct acpi_table_header *dmar)
+{
+ /* The DMAR is only stashed and provided via TXT on Intel systems */
+ if (memcmp(txt_dmar, "DMAR", 4))
+ return dmar;
+
+ return (struct acpi_table_header *)(txt_dmar);
+}
+
+/*
+ * If running within a TXT established DRTM, this is the proper way to reset
+ * the system if a failure occurs or a security issue is found.
+ */
+void __noreturn slaunch_txt_reset(void __iomem *txt,
+ const char *msg, u64 error)
+{
+ u64 one = 1, val;
+
+ pr_err("%s", msg);
+
+ /*
+ * This performs a TXT reset with a sticky error code. The reads of
+ * TXT_CR_E2STS act as barriers.
+ */
+ memcpy_toio(txt + TXT_CR_ERRORCODE, &error, sizeof(error));
+ memcpy_fromio(&val, txt + TXT_CR_E2STS, sizeof(val));
+ memcpy_toio(txt + TXT_CR_CMD_NO_SECRETS, &one, sizeof(one));
+ memcpy_fromio(&val, txt + TXT_CR_E2STS, sizeof(val));
+ memcpy_toio(txt + TXT_CR_CMD_UNLOCK_MEM_CONFIG, &one, sizeof(one));
+ memcpy_fromio(&val, txt + TXT_CR_E2STS, sizeof(val));
+ memcpy_toio(txt + TXT_CR_CMD_RESET, &one, sizeof(one));
+
+ for ( ; ; )
+ asm volatile ("hlt");
+
+ unreachable();
+}
+
+/*
+ * The TXT heap is too big to map all at once with early_ioremap
+ * so it is done a table at a time.
+ */
+static void __init *txt_early_get_heap_table(void __iomem *txt, u32 type,
+ u32 bytes)
+{
+ u64 base, size, offset = 0;
+ void *heap;
+ int i;
+
+ if (type > TXT_SINIT_TABLE_MAX)
+ slaunch_txt_reset(txt, "Error invalid table type for early heap walk\n",
+ SL_ERROR_HEAP_WALK);
+
+ memcpy_fromio(&base, txt + TXT_CR_HEAP_BASE, sizeof(base));
+ memcpy_fromio(&size, txt + TXT_CR_HEAP_SIZE, sizeof(size));
+
+ /* Iterate over heap tables looking for table of "type" */
+ for (i = 0; i < type; i++) {
+ base += offset;
+ heap = early_memremap(base, sizeof(u64));
+ if (!heap)
+ slaunch_txt_reset(txt, "Error early_memremap of heap for heap walk\n",
+ SL_ERROR_HEAP_MAP);
+
+ offset = *((u64 *)heap);
+
+ /*
+ * After the first iteration, any offset of zero is invalid and
+ * implies the TXT heap is corrupted.
+ */
+ if (!offset)
+ slaunch_txt_reset(txt, "Error invalid 0 offset in heap walk\n",
+ SL_ERROR_HEAP_ZERO_OFFSET);
+
+ early_memunmap(heap, sizeof(u64));
+ }
+
+ /* Skip the size field at the head of each table */
+ base += sizeof(u64);
+ heap = early_memremap(base, bytes);
+ if (!heap)
+ slaunch_txt_reset(txt, "Error early_memremap of heap section\n",
+ SL_ERROR_HEAP_MAP);
+
+ return heap;
+}
+
+static void __init txt_early_put_heap_table(void *addr, unsigned long size)
+{
+ early_memunmap(addr, size);
+}
+
+/*
+ * TXT uses a special set of VTd registers to protect all of memory from DMA
+ * until the IOMMU can be programmed to protect memory. There is the low
+ * memory PMR that can protect all memory up to 4G. The high memory PRM can
+ * be setup to protect all memory beyond 4Gb. Validate that these values cover
+ * what is expected.
+ */
+static void __init slaunch_verify_pmrs(void __iomem *txt)
+{
+ struct txt_os_sinit_data *os_sinit_data;
+ u32 field_offset, err = 0;
+ const char *errmsg = "";
+ unsigned long last_pfn;
+
+ field_offset = offsetof(struct txt_os_sinit_data, lcp_po_base);
+ os_sinit_data = txt_early_get_heap_table(txt, TXT_OS_SINIT_DATA_TABLE,
+ field_offset);
+
+ /* Save a copy */
+ vtd_pmr_lo_size = os_sinit_data->vtd_pmr_lo_size;
+
+ last_pfn = e820__end_of_ram_pfn();
+
+ /*
+ * First make sure the hi PMR covers all memory above 4G. In the
+ * unlikely case where there is < 4G on the system, the hi PMR will
+ * not be set.
+ */
+ if (os_sinit_data->vtd_pmr_hi_base != 0x0ULL) {
+ if (os_sinit_data->vtd_pmr_hi_base != 0x100000000ULL) {
+ err = SL_ERROR_HI_PMR_BASE;
+ errmsg = "Error hi PMR base\n";
+ goto out;
+ }
+
+ if (PFN_PHYS(last_pfn) > os_sinit_data->vtd_pmr_hi_base +
+ os_sinit_data->vtd_pmr_hi_size) {
+ err = SL_ERROR_HI_PMR_SIZE;
+ errmsg = "Error hi PMR size\n";
+ goto out;
+ }
+ }
+
+ /*
+ * Lo PMR base should always be 0. This was already checked in
+ * early stub.
+ */
+
+ /*
+ * Check that if the kernel was loaded below 4G, that it is protected
+ * by the lo PMR. Note this is the decompressed kernel. The ACM would
+ * have ensured the compressed kernel (the MLE image) was protected.
+ */
+ if (__pa_symbol(_end) < 0x100000000ULL && __pa_symbol(_end) > os_sinit_data->vtd_pmr_lo_size) {
+ err = SL_ERROR_LO_PMR_MLE;
+ errmsg = "Error lo PMR does not cover MLE kernel\n";
+ }
+
+ /*
+ * Other regions of interest like boot param, AP wake block, cmdline
+ * already checked for PMR coverage in the early stub code.
+ */
+
+out:
+ txt_early_put_heap_table(os_sinit_data, field_offset);
+
+ if (err)
+ slaunch_txt_reset(txt, errmsg, err);
+}
+
+static void __init slaunch_txt_reserve_range(u64 base, u64 size)
+{
+ int type;
+
+ type = e820__get_entry_type(base, base + size - 1);
+ if (type == E820_TYPE_RAM) {
+ pr_info("memblock reserve base: %llx size: %llx\n", base, size);
+ memblock_reserve(base, size);
+ }
+}
+
+/*
+ * For Intel, certain regions of memory must be marked as reserved by putting
+ * them on the memblock reserved list if they are not already e820 reserved.
+ * This includes:
+ * - The TXT HEAP
+ * - The ACM area
+ * - The TXT private register bank
+ * - The MDR list sent to the MLE by the ACM (see TXT specification)
+ * (Normally the above are properly reserved by firmware but if it was not
+ * done, reserve them now)
+ * - The AP wake block
+ * - TPM log external to the TXT heap
+ *
+ * Also if the low PMR doesn't cover all memory < 4G, any RAM regions above
+ * the low PMR must be reserved too.
+ */
+static void __init slaunch_txt_reserve(void __iomem *txt)
+{
+ struct txt_sinit_memory_descriptor_record *mdr;
+ struct txt_sinit_mle_data *sinit_mle_data;
+ u64 base, size, heap_base, heap_size;
+ u32 mdrnum, mdroffset, mdrslen;
+ u32 field_offset, i;
+ void *mdrs;
+
+ base = TXT_PRIV_CONFIG_REGS_BASE;
+ size = TXT_PUB_CONFIG_REGS_BASE - TXT_PRIV_CONFIG_REGS_BASE;
+ slaunch_txt_reserve_range(base, size);
+
+ memcpy_fromio(&heap_base, txt + TXT_CR_HEAP_BASE, sizeof(heap_base));
+ memcpy_fromio(&heap_size, txt + TXT_CR_HEAP_SIZE, sizeof(heap_size));
+ slaunch_txt_reserve_range(heap_base, heap_size);
+
+ memcpy_fromio(&base, txt + TXT_CR_SINIT_BASE, sizeof(base));
+ memcpy_fromio(&size, txt + TXT_CR_SINIT_SIZE, sizeof(size));
+ slaunch_txt_reserve_range(base, size);
+
+ field_offset = offsetof(struct txt_sinit_mle_data,
+ sinit_vtd_dmar_table_size);
+ sinit_mle_data = txt_early_get_heap_table(txt, TXT_SINIT_MLE_DATA_TABLE,
+ field_offset);
+
+ mdrnum = sinit_mle_data->num_of_sinit_mdrs;
+ mdroffset = sinit_mle_data->sinit_mdrs_table_offset;
+
+ txt_early_put_heap_table(sinit_mle_data, field_offset);
+
+ if (!mdrnum)
+ goto nomdr;
+
+ mdrslen = mdrnum * sizeof(struct txt_sinit_memory_descriptor_record);
+
+ mdrs = txt_early_get_heap_table(txt, TXT_SINIT_MLE_DATA_TABLE,
+ mdroffset + mdrslen - 8);
+
+ mdr = mdrs + mdroffset - 8;
+
+ for (i = 0; i < mdrnum; i++, mdr++) {
+ /* Spec says some entries can have length 0, ignore them */
+ if (mdr->type > 0 && mdr->length > 0)
+ slaunch_txt_reserve_range(mdr->address, mdr->length);
+ }
+
+ txt_early_put_heap_table(mdrs, mdroffset + mdrslen - 8);
+
+nomdr:
+ slaunch_txt_reserve_range(ap_wake_info.ap_wake_block,
+ ap_wake_info.ap_wake_block_size);
+
+ /*
+ * Earlier checks ensured that the event log was properly situated
+ * either inside the TXT heap or outside. This is a check to see if the
+ * event log needs to be reserved. If it is in the TXT heap, it is
+ * already reserved.
+ */
+ if (evtlog_addr < heap_base || evtlog_addr > (heap_base + heap_size))
+ slaunch_txt_reserve_range(evtlog_addr, evtlog_size);
+
+ for (i = 0; i < e820_table->nr_entries; i++) {
+ base = e820_table->entries[i].addr;
+ size = e820_table->entries[i].size;
+ if (base >= vtd_pmr_lo_size && base < 0x100000000ULL)
+ slaunch_txt_reserve_range(base, size);
+ else if (base < vtd_pmr_lo_size && base + size > vtd_pmr_lo_size)
+ slaunch_txt_reserve_range(vtd_pmr_lo_size,
+ base + size - vtd_pmr_lo_size);
+ }
+}
+
+/*
+ * TXT stashes a safe copy of the DMAR ACPI table to prevent tampering.
+ * It is stored in the TXT heap. Fetch it from there and make it available
+ * to the IOMMU driver.
+ */
+static void __init slaunch_copy_dmar_table(void __iomem *txt)
+{
+ struct txt_sinit_mle_data *sinit_mle_data;
+ u32 field_offset, dmar_size, dmar_offset;
+ void *dmar;
+
+ field_offset = offsetof(struct txt_sinit_mle_data,
+ processor_scrtm_status);
+ sinit_mle_data = txt_early_get_heap_table(txt, TXT_SINIT_MLE_DATA_TABLE,
+ field_offset);
+
+ dmar_size = sinit_mle_data->sinit_vtd_dmar_table_size;
+ dmar_offset = sinit_mle_data->sinit_vtd_dmar_table_offset;
+
+ txt_early_put_heap_table(sinit_mle_data, field_offset);
+
+ if (!dmar_size || !dmar_offset)
+ slaunch_txt_reset(txt, "Error invalid DMAR table values\n",
+ SL_ERROR_HEAP_INVALID_DMAR);
+
+ if (unlikely(dmar_size > PAGE_SIZE))
+ slaunch_txt_reset(txt, "Error DMAR too big to store\n",
+ SL_ERROR_HEAP_DMAR_SIZE);
+
+ dmar = txt_early_get_heap_table(txt, TXT_SINIT_MLE_DATA_TABLE,
+ dmar_offset + dmar_size - 8);
+ if (!dmar)
+ slaunch_txt_reset(txt, "Error early_ioremap of DMAR\n",
+ SL_ERROR_HEAP_DMAR_MAP);
+
+ memcpy(txt_dmar, dmar + dmar_offset - 8, dmar_size);
+
+ txt_early_put_heap_table(dmar, dmar_offset + dmar_size - 8);
+}
+
+/*
+ * The location of the safe AP wake code block is stored in the TXT heap.
+ * Fetch needed values here in the early init code for later use in SMP
+ * startup.
+ *
+ * Also get the TPM event log values are in the SLRT and have to be fetched.
+ * They will be put on the memblock reserve list later.
+ */
+static void __init slaunch_fetch_values(void __iomem *txt)
+{
+ struct txt_os_mle_data *os_mle_data;
+ struct slr_entry_log_info *log_info;
+ u8 *jmp_offset, *stacks_offset;
+ struct slr_table *slrt;
+ u32 size;
+
+ os_mle_data = txt_early_get_heap_table(txt, TXT_OS_MLE_DATA_TABLE,
+ sizeof(*os_mle_data));
+
+ ap_wake_info.ap_wake_block = os_mle_data->ap_wake_block;
+ ap_wake_info.ap_wake_block_size = os_mle_data->ap_wake_block_size;
+
+ jmp_offset = os_mle_data->mle_scratch + SL_SCRATCH_AP_JMP_OFFSET;
+ ap_wake_info.ap_jmp_offset = *((u32 *)jmp_offset);
+
+ stacks_offset = os_mle_data->mle_scratch + SL_SCRATCH_AP_STACKS_OFFSET;
+ ap_wake_info.ap_stacks_offset = *((u32 *)stacks_offset);
+
+ slrt = (struct slr_table *)early_memremap(os_mle_data->slrt, sizeof(*slrt));
+ if (!slrt)
+ slaunch_txt_reset(txt, "Error early_memremap of SLRT failed\n",
+ SL_ERROR_SLRT_MAP);
+
+ size = slrt->size;
+ early_memunmap(slrt, sizeof(*slrt));
+
+ slrt = (struct slr_table *)early_memremap(os_mle_data->slrt, size);
+ if (!slrt)
+ slaunch_txt_reset(txt, "Error early_memremap of SLRT failed\n",
+ SL_ERROR_SLRT_MAP);
+
+ log_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_LOG_INFO);
+
+ if (!log_info)
+ slaunch_txt_reset(txt, "SLRT missing logging info entry\n",
+ SL_ERROR_SLRT_MISSING_ENTRY);
+
+ evtlog_addr = log_info->addr;
+ evtlog_size = log_info->size;
+
+ early_memunmap(slrt, size);
+
+ txt_early_put_heap_table(os_mle_data, sizeof(*os_mle_data));
+}
+
+/*
+ * Called to fix the long jump address for the waiting APs to vector to
+ * the correct startup location in the Secure Launch stub in the rmpiggy.
+ */
+void __init slaunch_fixup_jump_vector(void)
+{
+ struct sl_ap_wake_info *ap_wake_info;
+ u32 *ap_jmp_ptr;
+
+ if ((slaunch_get_flags() & (SL_FLAG_ACTIVE|SL_FLAG_ARCH_TXT)) !=
+ (SL_FLAG_ACTIVE | SL_FLAG_ARCH_TXT))
+ return;
+
+ ap_wake_info = slaunch_get_ap_wake_info();
+
+ ap_jmp_ptr = (u32 *)__va(ap_wake_info->ap_wake_block +
+ ap_wake_info->ap_jmp_offset);
+
+ *ap_jmp_ptr = real_mode_header->sl_trampoline_start32;
+
+ pr_info("TXT AP startup vector address updated\n");
+}
+
+/*
+ * Intel TXT specific late stub setup and validation called from within
+ * x86 specific setup_arch().
+ */
+void __init slaunch_setup_txt(void)
+{
+ u64 one = TXT_REGVALUE_ONE, val;
+ void __iomem *txt;
+
+ if (!boot_cpu_has(X86_FEATURE_SMX))
+ return;
+
+ /*
+ * If booted through secure launch entry point, the loadflags
+ * option will be set.
+ */
+ if (!(boot_params.hdr.loadflags & SLAUNCH_FLAG))
+ return;
+
+ /*
+ * See if SENTER was done by reading the status register in the
+ * public space. If the public register space cannot be read, TXT may
+ * be disabled.
+ */
+ txt = early_ioremap(TXT_PUB_CONFIG_REGS_BASE,
+ TXT_NR_CONFIG_PAGES * PAGE_SIZE);
+ if (!txt)
+ panic("Error early_ioremap in TXT setup failed\n");
+
+ memcpy_fromio(&val, txt + TXT_CR_STS, sizeof(val));
+ early_iounmap(txt, TXT_NR_CONFIG_PAGES * PAGE_SIZE);
+
+ /* SENTER should have been done */
+ if (!(val & TXT_SENTER_DONE_STS))
+ panic("Error TXT.STS SENTER_DONE not set\n");
+
+ /* SEXIT should have been cleared */
+ if (val & TXT_SEXIT_DONE_STS)
+ panic("Error TXT.STS SEXIT_DONE set\n");
+
+ /* Now we want to use the private register space */
+ txt = early_ioremap(TXT_PRIV_CONFIG_REGS_BASE,
+ TXT_NR_CONFIG_PAGES * PAGE_SIZE);
+ if (!txt) {
+ /* This is really bad, no where to go from here */
+ panic("Error early_ioremap of TXT priv registers\n");
+ }
+
+ /*
+ * Try to read the Intel VID from the TXT private registers to see if
+ * TXT measured launch happened properly and the private space is
+ * available.
+ */
+ memcpy_fromio(&val, txt + TXT_CR_DIDVID, sizeof(val));
+ if ((val & 0xffff) != 0x8086) {
+ /*
+ * Can't do a proper TXT reset since it appears something is
+ * wrong even though SENTER happened and it should be in SMX
+ * mode.
+ */
+ panic("Invalid TXT vendor ID, not in SMX mode\n");
+ }
+
+ /* Set flags so subsequent code knows the status of the launch */
+ sl_flags |= (SL_FLAG_ACTIVE | SL_FLAG_ARCH_TXT);
+
+ /*
+ * Reading the proper DIDVID from the private register space means we
+ * are in SMX mode and private registers are open for read/write.
+ */
+
+ /* On Intel, have to handle TPM localities via TXT */
+ memcpy_toio(txt + TXT_CR_CMD_SECRETS, &one, sizeof(one));
+ memcpy_fromio(&val, txt + TXT_CR_E2STS, sizeof(val));
+ memcpy_toio(txt + TXT_CR_CMD_OPEN_LOCALITY1, &one, sizeof(one));
+ memcpy_fromio(&val, txt + TXT_CR_E2STS, sizeof(val));
+
+ slaunch_fetch_values(txt);
+
+ slaunch_verify_pmrs(txt);
+
+ slaunch_txt_reserve(txt);
+
+ slaunch_copy_dmar_table(txt);
+
+ early_iounmap(txt, TXT_NR_CONFIG_PAGES * PAGE_SIZE);
+
+ pr_info("Intel TXT setup complete\n");
+}
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 36d7427b1202..4b185c3f8f4c 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -28,6 +28,7 @@
#include <linux/iommu.h>
#include <linux/numa.h>
#include <linux/limits.h>
+#include <linux/slaunch.h>
#include <asm/irq_remapping.h>

#include "iommu.h"
@@ -660,6 +661,9 @@ parse_dmar_table(void)
*/
dmar_tbl = tboot_get_dmar_table(dmar_tbl);

+ /* If Secure Launch is active, it has similar logic */
+ dmar_tbl = slaunch_get_dmar_table(dmar_tbl);
+
dmar = (struct acpi_table_dmar *)dmar_tbl;
if (!dmar)
return -ENODEV;
--
2.39.3

2024-05-31 01:36:42

by Ross Philipson

Subject: [PATCH v9 11/19] kexec: Secure Launch kexec SEXIT support

Prior to running the next kernel via kexec, the Secure Launch code
closes down private SMX resources and does an SEXIT. This allows the
next kernel to start normally without any issues starting the APs etc.

Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/kernel/slaunch.c | 73 +++++++++++++++++++++++++++++++++++++++
kernel/kexec_core.c | 4 +++
2 files changed, 77 insertions(+)

diff --git a/arch/x86/kernel/slaunch.c b/arch/x86/kernel/slaunch.c
index 48c9ca78e241..f35b4ba433fa 100644
--- a/arch/x86/kernel/slaunch.c
+++ b/arch/x86/kernel/slaunch.c
@@ -523,3 +523,76 @@ void __init slaunch_setup_txt(void)

pr_info("Intel TXT setup complete\n");
}
+
+static inline void smx_getsec_sexit(void)
+{
+ asm volatile ("getsec\n"
+ : : "a" (SMX_X86_GETSEC_SEXIT));
+}
+
+/*
+ * Used during kexec and on reboot paths to finalize the TXT state
+ * and do an SEXIT exiting the DRTM and disabling SMX mode.
+ */
+void slaunch_finalize(int do_sexit)
+{
+ u64 one = TXT_REGVALUE_ONE, val;
+ void __iomem *config;
+
+ if ((slaunch_get_flags() & (SL_FLAG_ACTIVE | SL_FLAG_ARCH_TXT)) !=
+ (SL_FLAG_ACTIVE | SL_FLAG_ARCH_TXT))
+ return;
+
+ config = ioremap(TXT_PRIV_CONFIG_REGS_BASE, TXT_NR_CONFIG_PAGES *
+ PAGE_SIZE);
+ if (!config) {
+ pr_emerg("Error SEXIT failed to ioremap TXT private reqs\n");
+ return;
+ }
+
+ /* Clear secrets bit for SEXIT */
+ memcpy_toio(config + TXT_CR_CMD_NO_SECRETS, &one, sizeof(one));
+ memcpy_fromio(&val, config + TXT_CR_E2STS, sizeof(val));
+
+ /* Unlock memory configurations */
+ memcpy_toio(config + TXT_CR_CMD_UNLOCK_MEM_CONFIG, &one, sizeof(one));
+ memcpy_fromio(&val, config + TXT_CR_E2STS, sizeof(val));
+
+ /* Close the TXT private register space */
+ memcpy_toio(config + TXT_CR_CMD_CLOSE_PRIVATE, &one, sizeof(one));
+ memcpy_fromio(&val, config + TXT_CR_E2STS, sizeof(val));
+
+ /*
+ * Calls to iounmap are not being done because of the state of the
+ * system this late in the kexec process. Local IRQs are disabled and
+ * iounmap causes a TLB flush which in turn causes a warning. Leaving
+ * thse mappings is not an issue since the next kernel is going to
+ * completely re-setup memory management.
+ */
+
+ /* Map public registers and do a final read fence */
+ config = ioremap(TXT_PUB_CONFIG_REGS_BASE, TXT_NR_CONFIG_PAGES *
+ PAGE_SIZE);
+ if (!config) {
+ pr_emerg("Error SEXIT failed to ioremap TXT public reqs\n");
+ return;
+ }
+
+ memcpy_fromio(&val, config + TXT_CR_E2STS, sizeof(val));
+
+ pr_emerg("TXT clear secrets bit and unlock memory complete.\n");
+
+ if (!do_sexit)
+ return;
+
+ if (smp_processor_id() != 0)
+ panic("Error TXT SEXIT must be called on CPU 0\n");
+
+ /* In case SMX mode was disabled, enable it for SEXIT */
+ cr4_set_bits(X86_CR4_SMXE);
+
+ /* Do the SEXIT SMX operation */
+ smx_getsec_sexit();
+
+ pr_info("TXT SEXIT complete.\n");
+}
diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index 0e96f6b24344..ba2fd1c0ddd9 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -40,6 +40,7 @@
#include <linux/hugetlb.h>
#include <linux/objtool.h>
#include <linux/kmsg_dump.h>
+#include <linux/slaunch.h>

#include <asm/page.h>
#include <asm/sections.h>
@@ -1046,6 +1047,9 @@ int kernel_kexec(void)
cpu_hotplug_enable();
pr_notice("Starting new kernel\n");
machine_shutdown();
+
+ /* Finalize TXT registers and do SEXIT */
+ slaunch_finalize(1);
}

kmsg_dump(KMSG_DUMP_SHUTDOWN);
--
2.39.3

2024-05-31 01:36:55

by Ross Philipson

Subject: [PATCH v9 14/19] tpm: Ensure tpm is in known state at startup

From: "Daniel P. Smith" <[email protected]>

When tis core initializes, it assumes all localities are closed. There
are cases when this may not be the case. This commit addresses this by
ensuring all localities are closed before initializing begins.

Signed-off-by: Daniel P. Smith <[email protected]>
Signed-off-by: Ross Philipson <[email protected]>
---
drivers/char/tpm/tpm_tis_core.c | 11 ++++++++++-
include/linux/tpm.h | 6 ++++++
2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 7c1761bd6000..9fb53bb3e73f 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -1104,7 +1104,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
u32 intmask;
u32 clkrun_val;
u8 rid;
- int rc, probe;
+ int rc, probe, i;
struct tpm_chip *chip;

chip = tpmm_chip_alloc(dev, &tpm_tis);
@@ -1166,6 +1166,15 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
goto out_err;
}

+ /*
+ * There are environments, like Intel TXT, that may leave a TPM
+ * locality open. Close all localities to start from a known state.
+ */
+ for (i = 0; i <= TPM_MAX_LOCALITY; i++) {
+ if (check_locality(chip, i))
+ tpm_tis_relinquish_locality(chip, i);
+ }
+
/* Take control of the TPM's interrupt hardware and shut it off */
rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
if (rc < 0)
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index c17e4efbb2e5..363f7078c3a9 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -147,6 +147,12 @@ struct tpm_chip_seqops {
*/
#define TPM2_MAX_CONTEXT_SIZE 4096

+/*
+ * The maximum locality (0 - 4) for a TPM, as defined in section 3.2 of the
+ * Client Platform Profile Specification.
+ */
+#define TPM_MAX_LOCALITY 4
+
struct tpm_chip {
struct device dev;
struct device devs;
--
2.39.3

2024-05-31 01:37:08

by Ross Philipson

Subject: [PATCH v9 15/19] tpm: Make locality requests return consistent values

From: "Daniel P. Smith" <[email protected]>

The function tpm_tis_request_locality() is expected to return the locality
value that was requested, or a negative error code upon failure. If it is called
while locality_count of struct tis_data is non-zero, no actual locality request
will be sent. Because the ret variable is initially set to 0, the
locality_count will still get increased, and the function will return 0. For a
caller, this would indicate that locality 0 was successfully requested and not
the state changes just mentioned.

Additionally, the function __tpm_tis_request_locality() provides inconsistent
error codes. It will provide either a failed IO write or a -1 should it have
timed out waiting for locality request to succeed.

This commit changes __tpm_tis_request_locality() to return valid negative error
codes to reflect the reason it fails. It then adjusts the return value check in
tpm_tis_request_locality() to check for a non-negative return value before
incrementing locality_cout. In addition, the initial value of the ret value is
set to a negative error to ensure the check does not pass if
__tpm_tis_request_locality() is not called.

Signed-off-by: Daniel P. Smith <[email protected]>
Signed-off-by: Ross Philipson <[email protected]>
---
drivers/char/tpm/tpm_tis_core.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 9fb53bb3e73f..685bdeadec51 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -208,7 +208,7 @@ static int __tpm_tis_request_locality(struct tpm_chip *chip, int l)
again:
timeout = stop - jiffies;
if ((long)timeout <= 0)
- return -1;
+ return -EBUSY;
rc = wait_event_interruptible_timeout(priv->int_queue,
(check_locality
(chip, l)),
@@ -227,18 +227,21 @@ static int __tpm_tis_request_locality(struct tpm_chip *chip, int l)
tpm_msleep(TPM_TIMEOUT);
} while (time_before(jiffies, stop));
}
- return -1;
+ return -EBUSY;
}

static int tpm_tis_request_locality(struct tpm_chip *chip, int l)
{
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
- int ret = 0;
+ int ret = -EBUSY;
+
+ if (l < 0 || l > TPM_MAX_LOCALITY)
+ return -EINVAL;

mutex_lock(&priv->locality_count_mutex);
if (priv->locality_count == 0)
ret = __tpm_tis_request_locality(chip, l);
- if (!ret)
+ if (ret >= 0)
priv->locality_count++;
mutex_unlock(&priv->locality_count_mutex);
return ret;
--
2.39.3

2024-05-31 01:38:06

by Ross Philipson

Subject: [PATCH v9 16/19] tpm: Add ability to set the preferred locality the TPM chip uses

Curently the locality is hard coded to 0 but for DRTM support, access
is needed to localities 1 through 4.

Signed-off-by: Ross Philipson <[email protected]>
---
drivers/char/tpm/tpm-chip.c | 24 +++++++++++++++++++++++-
drivers/char/tpm/tpm-interface.c | 15 +++++++++++++++
drivers/char/tpm/tpm.h | 1 +
include/linux/tpm.h | 4 ++++
4 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 854546000c92..73eac54d61fb 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -44,7 +44,7 @@ static int tpm_request_locality(struct tpm_chip *chip)
if (!chip->ops->request_locality)
return 0;

- rc = chip->ops->request_locality(chip, 0);
+ rc = chip->ops->request_locality(chip, chip->pref_locality);
if (rc < 0)
return rc;

@@ -143,6 +143,27 @@ void tpm_chip_stop(struct tpm_chip *chip)
}
EXPORT_SYMBOL_GPL(tpm_chip_stop);

+/**
+ * tpm_chip_preferred_locality() - set the TPM chip preferred locality to open
+ * @chip: a TPM chip to use
+ * @locality: the preferred locality
+ *
+ * Return:
+ * * true - Preferred locality set
+ * * false - Invalid locality specified
+ */
+bool tpm_chip_preferred_locality(struct tpm_chip *chip, int locality)
+{
+ if (locality < 0 || locality >=TPM_MAX_LOCALITY)
+ return false;
+
+ mutex_lock(&chip->tpm_mutex);
+ chip->pref_locality = locality;
+ mutex_unlock(&chip->tpm_mutex);
+ return true;
+}
+EXPORT_SYMBOL_GPL(tpm_chip_preferred_locality);
+
/**
* tpm_try_get_ops() - Get a ref to the tpm_chip
* @chip: Chip to ref
@@ -374,6 +395,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
}

chip->locality = -1;
+ chip->pref_locality = 0;
return chip;

out:
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 5da134f12c9a..35f14ccecf0e 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -274,6 +274,21 @@ int tpm_is_tpm2(struct tpm_chip *chip)
}
EXPORT_SYMBOL_GPL(tpm_is_tpm2);

+/**
+ * tpm_preferred_locality() - set the TPM chip preferred locality to open
+ * @chip: a TPM chip to use
+ * @locality: the preferred locality
+ *
+ * Return:
+ * * true - Preferred locality set
+ * * false - Invalid locality specified
+ */
+bool tpm_preferred_locality(struct tpm_chip *chip, int locality)
+{
+ return tpm_chip_preferred_locality(chip, locality);
+}
+EXPORT_SYMBOL_GPL(tpm_preferred_locality);
+
/**
* tpm_pcr_read - read a PCR value from SHA1 bank
* @chip: a &struct tpm_chip instance, %NULL for the default chip
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 6b8b9956ba69..be465422d3fa 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -267,6 +267,7 @@ static inline void tpm_msleep(unsigned int delay_msec)
int tpm_chip_bootstrap(struct tpm_chip *chip);
int tpm_chip_start(struct tpm_chip *chip);
void tpm_chip_stop(struct tpm_chip *chip);
+bool tpm_chip_preferred_locality(struct tpm_chip *chip, int locality);
struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip);

struct tpm_chip *tpm_chip_alloc(struct device *dev,
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 363f7078c3a9..935a3457d7c8 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -219,6 +219,9 @@ struct tpm_chip {
u8 null_ec_key_y[EC_PT_SZ];
struct tpm2_auth *auth;
#endif
+
+ /* preferred locality - default 0 */
+ int pref_locality;
};

#define TPM_HEADER_SIZE 10
@@ -461,6 +464,7 @@ static inline u32 tpm2_rc_value(u32 rc)
#if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE)

extern int tpm_is_tpm2(struct tpm_chip *chip);
+extern bool tpm_preferred_locality(struct tpm_chip *chip, int locality);
extern __must_check int tpm_try_get_ops(struct tpm_chip *chip);
extern void tpm_put_ops(struct tpm_chip *chip);
extern ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf,
--
2.39.3

2024-05-31 01:38:11

by Ross Philipson

Subject: [PATCH v9 18/19] x86: Secure Launch late initcall platform module

From: "Daniel P. Smith" <[email protected]>

The Secure Launch platform module is a late init module. During the
init call, the TPM event log is read and measurements taken in the
early boot stub code are located. These measurements are extended
into the TPM PCRs using the mainline TPM kernel driver.

The platform module also registers the securityfs nodes to allow
access to TXT register fields on Intel along with the fetching of
and writing events to the late launch TPM log.

Signed-off-by: Daniel P. Smith <[email protected]>
Signed-off-by: garnetgrimm <[email protected]>
Signed-off-by: Ross Philipson <[email protected]>
---
arch/x86/kernel/Makefile | 1 +
arch/x86/kernel/slmodule.c | 513 +++++++++++++++++++++++++++++++++++++
2 files changed, 514 insertions(+)
create mode 100644 arch/x86/kernel/slmodule.c

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index b35ca99ab0a0..f2432c4a747a 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -77,6 +77,7 @@ obj-$(CONFIG_IA32_EMULATION) += tls.o
obj-y += step.o
obj-$(CONFIG_INTEL_TXT) += tboot.o
obj-$(CONFIG_SECURE_LAUNCH) += slaunch.o
+obj-$(CONFIG_SECURE_LAUNCH) += slmodule.o
obj-$(CONFIG_ISA_DMA_API) += i8237.o
obj-y += stacktrace.o
obj-y += cpu/
diff --git a/arch/x86/kernel/slmodule.c b/arch/x86/kernel/slmodule.c
new file mode 100644
index 000000000000..0e1354e3a914
--- /dev/null
+++ b/arch/x86/kernel/slmodule.c
@@ -0,0 +1,513 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Secure Launch late validation/setup, securityfs exposure and finalization.
+ *
+ * Copyright (c) 2024 Apertus Solutions, LLC
+ * Copyright (c) 2024 Assured Information Security, Inc.
+ * Copyright (c) 2024, Oracle and/or its affiliates.
+ *
+ * Co-developed-by: Garnet T. Grimm <[email protected]>
+ * Signed-off-by: Garnet T. Grimm <[email protected]>
+ * Signed-off-by: Daniel P. Smith <[email protected]>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+#include <linux/uaccess.h>
+#include <linux/security.h>
+#include <linux/memblock.h>
+#include <linux/tpm.h>
+#include <asm/segment.h>
+#include <asm/sections.h>
+#include <crypto/sha2.h>
+#include <linux/slr_table.h>
+#include <linux/slaunch.h>
+
+/*
+ * The macro DECLARE_TXT_PUB_READ_U is used to read values from the TXT
+ * public registers as unsigned values.
+ */
+#define DECLARE_TXT_PUB_READ_U(size, fmt, msg_size) \
+static ssize_t txt_pub_read_u##size(unsigned int offset, \
+ loff_t *read_offset, \
+ size_t read_len, \
+ char __user *buf) \
+{ \
+ char msg_buffer[msg_size]; \
+ u##size reg_value = 0; \
+ void __iomem *txt; \
+ \
+ txt = ioremap(TXT_PUB_CONFIG_REGS_BASE, \
+ TXT_NR_CONFIG_PAGES * PAGE_SIZE); \
+ if (!txt) \
+ return -EFAULT; \
+ memcpy_fromio(&reg_value, txt + offset, sizeof(u##size)); \
+ iounmap(txt); \
+ snprintf(msg_buffer, msg_size, fmt, reg_value); \
+ return simple_read_from_buffer(buf, read_len, read_offset, \
+ &msg_buffer, msg_size); \
+}
+
+DECLARE_TXT_PUB_READ_U(8, "%#04x\n", 6);
+DECLARE_TXT_PUB_READ_U(32, "%#010x\n", 12);
+DECLARE_TXT_PUB_READ_U(64, "%#018llx\n", 20);
+
+#define DECLARE_TXT_FOPS(reg_name, reg_offset, reg_size) \
+static ssize_t txt_##reg_name##_read(struct file *flip, \
+ char __user *buf, size_t read_len, loff_t *read_offset) \
+{ \
+ return txt_pub_read_u##reg_size(reg_offset, read_offset, \
+ read_len, buf); \
+} \
+static const struct file_operations reg_name##_ops = { \
+ .read = txt_##reg_name##_read, \
+}
+
+DECLARE_TXT_FOPS(sts, TXT_CR_STS, 64);
+DECLARE_TXT_FOPS(ests, TXT_CR_ESTS, 8);
+DECLARE_TXT_FOPS(errorcode, TXT_CR_ERRORCODE, 32);
+DECLARE_TXT_FOPS(didvid, TXT_CR_DIDVID, 64);
+DECLARE_TXT_FOPS(e2sts, TXT_CR_E2STS, 64);
+DECLARE_TXT_FOPS(ver_emif, TXT_CR_VER_EMIF, 32);
+DECLARE_TXT_FOPS(scratchpad, TXT_CR_SCRATCHPAD, 64);
+
+/*
+ * Securityfs exposure
+ */
+struct memfile {
+ char *name;
+ void *addr;
+ size_t size;
+};
+
+static struct memfile sl_evtlog = {"eventlog", NULL, 0};
+static void *txt_heap;
+static struct txt_heap_event_log_pointer2_1_element *evtlog20;
+static DEFINE_MUTEX(sl_evt_log_mutex);
+
+static ssize_t sl_evtlog_read(struct file *file, char __user *buf,
+ size_t count, loff_t *pos)
+{
+ ssize_t size;
+
+ if (!sl_evtlog.addr)
+ return 0;
+
+ mutex_lock(&sl_evt_log_mutex);
+ size = simple_read_from_buffer(buf, count, pos, sl_evtlog.addr,
+ sl_evtlog.size);
+ mutex_unlock(&sl_evt_log_mutex);
+
+ return size;
+}
+
+static ssize_t sl_evtlog_write(struct file *file, const char __user *buf,
+ size_t datalen, loff_t *ppos)
+{
+ ssize_t result;
+ char *data;
+
+ if (!sl_evtlog.addr)
+ return 0;
+
+ /* No partial writes. */
+ result = -EINVAL;
+ if (*ppos != 0)
+ goto out;
+
+ data = memdup_user(buf, datalen);
+ if (IS_ERR(data)) {
+ result = PTR_ERR(data);
+ goto out;
+ }
+
+ mutex_lock(&sl_evt_log_mutex);
+ if (evtlog20)
+ result = tpm20_log_event(evtlog20, sl_evtlog.addr,
+ sl_evtlog.size, datalen, data);
+ else
+ result = tpm12_log_event(sl_evtlog.addr, sl_evtlog.size,
+ datalen, data);
+ mutex_unlock(&sl_evt_log_mutex);
+
+ kfree(data);
+out:
+ return result;
+}
+
+static const struct file_operations sl_evtlog_ops = {
+ .read = sl_evtlog_read,
+ .write = sl_evtlog_write,
+ .llseek = default_llseek,
+};
+
+struct sfs_file {
+ const char *name;
+ const struct file_operations *fops;
+};
+
+#define SL_TXT_ENTRY_COUNT 7
+static const struct sfs_file sl_txt_files[] = {
+ { "sts", &sts_ops },
+ { "ests", &ests_ops },
+ { "errorcode", &errorcode_ops },
+ { "didvid", &didvid_ops },
+ { "ver_emif", &ver_emif_ops },
+ { "scratchpad", &scratchpad_ops },
+ { "e2sts", &e2sts_ops }
+};
+
+/* sysfs file handles */
+static struct dentry *slaunch_dir;
+static struct dentry *event_file;
+static struct dentry *txt_dir;
+static struct dentry *txt_entries[SL_TXT_ENTRY_COUNT];
+
+static long slaunch_expose_securityfs(void)
+{
+ long ret = 0;
+ int i;
+
+ slaunch_dir = securityfs_create_dir("slaunch", NULL);
+ if (IS_ERR(slaunch_dir))
+ return PTR_ERR(slaunch_dir);
+
+ if (slaunch_get_flags() & SL_FLAG_ARCH_TXT) {
+ txt_dir = securityfs_create_dir("txt", slaunch_dir);
+ if (IS_ERR(txt_dir)) {
+ ret = PTR_ERR(txt_dir);
+ goto remove_slaunch;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(sl_txt_files); i++) {
+ txt_entries[i] = securityfs_create_file(
+ sl_txt_files[i].name, 0440,
+ txt_dir, NULL,
+ sl_txt_files[i].fops);
+ if (IS_ERR(txt_entries[i])) {
+ ret = PTR_ERR(txt_entries[i]);
+ goto remove_files;
+ }
+ }
+ }
+
+ if (sl_evtlog.addr) {
+ event_file = securityfs_create_file(sl_evtlog.name, 0440,
+ slaunch_dir, NULL,
+ &sl_evtlog_ops);
+ if (IS_ERR(event_file)) {
+ ret = PTR_ERR(event_file);
+ goto remove_files;
+ }
+ }
+
+ return 0;
+
+remove_files:
+ if (slaunch_get_flags() & SL_FLAG_ARCH_TXT) {
+ while (--i >= 0)
+ securityfs_remove(txt_entries[i]);
+ securityfs_remove(txt_dir);
+ }
+
+remove_slaunch:
+ securityfs_remove(slaunch_dir);
+
+ return ret;
+}
+
+static void slaunch_teardown_securityfs(void)
+{
+ int i;
+
+ securityfs_remove(event_file);
+ if (sl_evtlog.addr) {
+ memunmap(sl_evtlog.addr);
+ sl_evtlog.addr = NULL;
+ }
+ sl_evtlog.size = 0;
+
+ if (slaunch_get_flags() & SL_FLAG_ARCH_TXT) {
+ for (i = 0; i < ARRAY_SIZE(sl_txt_files); i++)
+ securityfs_remove(txt_entries[i]);
+
+ securityfs_remove(txt_dir);
+
+ if (txt_heap) {
+ memunmap(txt_heap);
+ txt_heap = NULL;
+ }
+ }
+
+ securityfs_remove(slaunch_dir);
+}
+
+static void slaunch_intel_evtlog(void __iomem *txt)
+{
+ struct slr_entry_log_info *log_info;
+ struct txt_os_mle_data *params;
+ struct slr_table *slrt;
+ void *os_sinit_data;
+ u64 base, size;
+
+ memcpy_fromio(&base, txt + TXT_CR_HEAP_BASE, sizeof(base));
+ memcpy_fromio(&size, txt + TXT_CR_HEAP_SIZE, sizeof(size));
+
+ /* now map TXT heap */
+ txt_heap = memremap(base, size, MEMREMAP_WB);
+ if (!txt_heap)
+ slaunch_txt_reset(txt, "Error failed to memremap TXT heap\n",
+ SL_ERROR_HEAP_MAP);
+
+ params = (struct txt_os_mle_data *)txt_os_mle_data_start(txt_heap);
+
+ /* Get the SLRT and remap it */
+ slrt = memremap(params->slrt, sizeof(*slrt), MEMREMAP_WB);
+ if (!slrt)
+ slaunch_txt_reset(txt, "Error failed to memremap SLR Table\n",
+ SL_ERROR_SLRT_MAP);
+ size = slrt->size;
+ memunmap(slrt);
+
+ slrt = memremap(params->slrt, size, MEMREMAP_WB);
+ if (!slrt)
+ slaunch_txt_reset(txt, "Error failed to memremap SLR Table\n",
+ SL_ERROR_SLRT_MAP);
+
+ log_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_LOG_INFO);
+ if (!log_info)
+ slaunch_txt_reset(txt, "Error failed to memremap SLR Table\n",
+ SL_ERROR_SLRT_MISSING_ENTRY);
+
+ sl_evtlog.size = log_info->size;
+ sl_evtlog.addr = memremap(log_info->addr, log_info->size,
+ MEMREMAP_WB);
+ if (!sl_evtlog.addr)
+ slaunch_txt_reset(txt, "Error failed to memremap TPM event log\n",
+ SL_ERROR_EVENTLOG_MAP);
+
+ memunmap(slrt);
+
+ /* Determine if this is TPM 1.2 or 2.0 event log */
+ if (memcmp(sl_evtlog.addr + sizeof(struct tcg_pcr_event),
+ TCG_SPECID_SIG, sizeof(TCG_SPECID_SIG)))
+ return; /* looks like it is not 2.0 */
+
+ /* For TPM 2.0 logs, the extended heap element must be located */
+ os_sinit_data = txt_os_sinit_data_start(txt_heap);
+
+ evtlog20 = tpm20_find_log2_1_element(os_sinit_data);
+
+ /*
+ * If this fails, things are in really bad shape. Any attempt to write
+ * events to the log will fail.
+ */
+ if (!evtlog20)
+ slaunch_txt_reset(txt, "Error failed to find TPM20 event log element\n",
+ SL_ERROR_TPM_INVALID_LOG20);
+}
+
+static void slaunch_tpm20_extend_event(struct tpm_chip *tpm, void __iomem *txt,
+ struct tcg_pcr_event2_head *event)
+{
+ u16 *alg_id_field = (u16 *)((u8 *)event + sizeof(struct tcg_pcr_event2_head));
+ struct tpm_digest *digests;
+ u8 *dptr;
+ u32 i, j;
+ int ret;
+
+ digests = kcalloc(tpm->nr_allocated_banks, sizeof(*digests),
+ GFP_KERNEL);
+ if (!digests)
+ slaunch_txt_reset(txt, "Failed to allocate array of digests\n",
+ SL_ERROR_GENERIC);
+
+ for (i = 0; i < tpm->nr_allocated_banks; i++)
+ digests[i].alg_id = tpm->allocated_banks[i].alg_id;
+
+ /* Early SL code ensured there was a max count of 2 digests */
+ for (i = 0; i < event->count; i++) {
+ dptr = (u8 *)alg_id_field + sizeof(u16);
+
+ for (j = 0; j < tpm->nr_allocated_banks; j++) {
+ if (digests[j].alg_id != *alg_id_field)
+ continue;
+
+ switch (digests[j].alg_id) {
+ case TPM_ALG_SHA256:
+ memcpy(&digests[j].digest[0], dptr,
+ SHA256_DIGEST_SIZE);
+ alg_id_field = (u16 *)((u8 *)alg_id_field +
+ SHA256_DIGEST_SIZE + sizeof(u16));
+ break;
+ case TPM_ALG_SHA1:
+ memcpy(&digests[j].digest[0], dptr,
+ SHA1_DIGEST_SIZE);
+ alg_id_field = (u16 *)((u8 *)alg_id_field +
+ SHA1_DIGEST_SIZE + sizeof(u16));
+ break;
+ default:
+ break;
+ }
+ }
+ }
+
+ ret = tpm_pcr_extend(tpm, event->pcr_idx, digests);
+ if (ret) {
+ pr_err("Error extending TPM20 PCR, result: %d\n", ret);
+ slaunch_txt_reset(txt, "Failed to extend TPM20 PCR\n",
+ SL_ERROR_TPM_EXTEND);
+ }
+
+ kfree(digests);
+}
+
+static void slaunch_tpm20_extend(struct tpm_chip *tpm, void __iomem *txt)
+{
+ struct tcg_pcr_event *event_header;
+ struct tcg_pcr_event2_head *event;
+ int start = 0, end = 0, size;
+
+ event_header = (struct tcg_pcr_event *)(sl_evtlog.addr +
+ evtlog20->first_record_offset);
+
+ /* Skip first TPM 1.2 event to get to first TPM 2.0 event */
+ event = (struct tcg_pcr_event2_head *)((u8 *)event_header +
+ sizeof(struct tcg_pcr_event) +
+ event_header->event_size);
+
+ while ((void *)event < sl_evtlog.addr + evtlog20->next_record_offset) {
+ size = __calc_tpm2_event_size(event, event_header, false);
+ if (!size)
+ slaunch_txt_reset(txt, "TPM20 invalid event in event log\n",
+ SL_ERROR_TPM_INVALID_EVENT);
+
+ /*
+ * Marker events indicate where the Secure Launch early stub
+ * started and ended adding post launch events.
+ */
+ if (event->event_type == TXT_EVTYPE_SLAUNCH_END) {
+ end = 1;
+ break;
+ } else if (event->event_type == TXT_EVTYPE_SLAUNCH_START) {
+ start = 1;
+ goto next;
+ }
+
+ if (start)
+ slaunch_tpm20_extend_event(tpm, txt, event);
+
+next:
+ event = (struct tcg_pcr_event2_head *)((u8 *)event + size);
+ }
+
+ if (!start || !end)
+ slaunch_txt_reset(txt, "Missing start or end events for extending TPM20 PCRs\n",
+ SL_ERROR_TPM_EXTEND);
+}
+
+static void slaunch_tpm12_extend(struct tpm_chip *tpm, void __iomem *txt)
+{
+ struct tpm12_event_log_header *event_header;
+ struct tcg_pcr_event *event;
+ struct tpm_digest digest;
+ int start = 0, end = 0;
+ int size, ret;
+
+ event_header = (struct tpm12_event_log_header *)sl_evtlog.addr;
+ event = (struct tcg_pcr_event *)((u8 *)event_header +
+ sizeof(struct tpm12_event_log_header));
+
+ while ((void *)event < sl_evtlog.addr + event_header->next_event_offset) {
+ size = sizeof(struct tcg_pcr_event) + event->event_size;
+
+ /*
+ * Marker events indicate where the Secure Launch early stub
+ * started and ended adding post launch events.
+ */
+ if (event->event_type == TXT_EVTYPE_SLAUNCH_END) {
+ end = 1;
+ break;
+ } else if (event->event_type == TXT_EVTYPE_SLAUNCH_START) {
+ start = 1;
+ goto next;
+ }
+
+ if (start) {
+ memset(&digest.digest[0], 0, TPM_MAX_DIGEST_SIZE);
+ digest.alg_id = TPM_ALG_SHA1;
+ memcpy(&digest.digest[0], &event->digest[0],
+ SHA1_DIGEST_SIZE);
+
+ ret = tpm_pcr_extend(tpm, event->pcr_idx, &digest);
+ if (ret) {
+ pr_err("Error extending TPM12 PCR, result: %d\n", ret);
+ slaunch_txt_reset(txt, "Failed to extend TPM12 PCR\n",
+ SL_ERROR_TPM_EXTEND);
+ }
+ }
+
+next:
+ event = (struct tcg_pcr_event *)((u8 *)event + size);
+ }
+
+ if (!start || !end)
+ slaunch_txt_reset(txt, "Missing start or end events for extending TPM12 PCRs\n",
+ SL_ERROR_TPM_EXTEND);
+}
+
+static void slaunch_pcr_extend(void __iomem *txt)
+{
+ struct tpm_chip *tpm;
+
+ tpm = tpm_default_chip();
+ if (!tpm)
+ slaunch_txt_reset(txt, "Could not get default TPM chip\n",
+ SL_ERROR_TPM_INIT);
+
+ if (!tpm_preferred_locality(tpm, 2))
+ slaunch_txt_reset(txt, "Could not set TPM chip locality 2\n",
+ SL_ERROR_TPM_INIT);
+
+ if (evtlog20)
+ slaunch_tpm20_extend(tpm, txt);
+ else
+ slaunch_tpm12_extend(tpm, txt);
+
+ tpm_preferred_locality(tpm, 0);
+}
+
+static int __init slaunch_module_init(void)
+{
+ void __iomem *txt;
+
+ /* Check to see if Secure Launch happened */
+ if ((slaunch_get_flags() & (SL_FLAG_ACTIVE|SL_FLAG_ARCH_TXT)) !=
+ (SL_FLAG_ACTIVE | SL_FLAG_ARCH_TXT))
+ return 0;
+
+ txt = ioremap(TXT_PRIV_CONFIG_REGS_BASE, TXT_NR_CONFIG_PAGES *
+ PAGE_SIZE);
+ if (!txt)
+ panic("Error ioremap of TXT priv registers\n");
+
+ /* Only Intel TXT is supported at this point */
+ slaunch_intel_evtlog(txt);
+ slaunch_pcr_extend(txt);
+ iounmap(txt);
+
+ return slaunch_expose_securityfs();
+}
+
+static void __exit slaunch_module_exit(void)
+{
+ slaunch_teardown_securityfs();
+}
+
+late_initcall(slaunch_module_init);
+__exitcall(slaunch_module_exit);
--
2.39.3

2024-05-31 11:00:30

by Ard Biesheuvel

Subject: Re: [PATCH v9 08/19] x86: Secure Launch kernel early boot stub

Hello Ross,

On Fri, 31 May 2024 at 03:32, Ross Philipson <[email protected]> wrote:
>
> The Secure Launch (SL) stub provides the entry point for Intel TXT (and
> later AMD SKINIT) to vector to during the late launch. The symbol
> sl_stub_entry is that entry point and its offset into the kernel is
> conveyed to the launching code using the MLE (Measured Launch
> Environment) header in the structure named mle_header. The offset of the
> MLE header is set in the kernel_info. The routine sl_stub contains the
> very early late launch setup code responsible for setting up the basic
> environment to allow the normal kernel startup_32 code to proceed. It is
> also responsible for properly waking and handling the APs on Intel
> platforms. The routine sl_main which runs after entering 64b mode is
> responsible for measuring configuration and module information before
> it is used like the boot params, the kernel command line, the TXT heap,
> an external initramfs, etc.
>
> Signed-off-by: Ross Philipson <[email protected]>
> ---
> Documentation/arch/x86/boot.rst | 21 +
> arch/x86/boot/compressed/Makefile | 3 +-
> arch/x86/boot/compressed/head_64.S | 30 +
> arch/x86/boot/compressed/kernel_info.S | 34 ++
> arch/x86/boot/compressed/sl_main.c | 577 ++++++++++++++++++++
> arch/x86/boot/compressed/sl_stub.S | 725 +++++++++++++++++++++++++
> arch/x86/include/asm/msr-index.h | 5 +
> arch/x86/include/uapi/asm/bootparam.h | 1 +
> arch/x86/kernel/asm-offsets.c | 20 +
> 9 files changed, 1415 insertions(+), 1 deletion(-)
> create mode 100644 arch/x86/boot/compressed/sl_main.c
> create mode 100644 arch/x86/boot/compressed/sl_stub.S
>
> diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst
> index 4fd492cb4970..295cdf9bcbdb 100644
> --- a/Documentation/arch/x86/boot.rst
> +++ b/Documentation/arch/x86/boot.rst
> @@ -482,6 +482,14 @@ Protocol: 2.00+
> - If 1, KASLR enabled.
> - If 0, KASLR disabled.
>
> + Bit 2 (kernel internal): SLAUNCH_FLAG
> +
> + - Used internally by the setup kernel to communicate
> + Secure Launch status to kernel proper.
> +
> + - If 1, Secure Launch enabled.
> + - If 0, Secure Launch disabled.
> +
> Bit 5 (write): QUIET_FLAG
>
> - If 0, print early messages.
> @@ -1028,6 +1036,19 @@ Offset/size: 0x000c/4
>
> This field contains maximal allowed type for setup_data and setup_indirect structs.
>
> +============ =================
> +Field name: mle_header_offset
> +Offset/size: 0x0010/4
> +============ =================
> +
> + This field contains the offset to the Secure Launch Measured Launch Environment
> + (MLE) header. This offset is used to locate information needed during a secure
> + late launch using Intel TXT. If the offset is zero, the kernel does not have
> + Secure Launch capabilities. The MLE entry point is called from TXT on the BSP
> + following a success measured launch. The specific state of the processors is
> + outlined in the TXT Software Development Guide, the latest can be found here:
> + https://www.intel.com/content/dam/www/public/us/en/documents/guides/intel-txt-software-development-guide.pdf
> +
>

Could we just repaint this field as the offset relative to the start
of kernel_info rather than relative to the start of the image? That
way, there is no need for patch #1, and given that the consumer of
this field accesses it via kernel_info, I wouldn't expect any issues
in applying this offset to obtain the actual address.


> The Image Checksum
> ==================
> diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
> index 9189a0e28686..9076a248d4b4 100644
> --- a/arch/x86/boot/compressed/Makefile
> +++ b/arch/x86/boot/compressed/Makefile
> @@ -118,7 +118,8 @@ vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
> vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_mixed.o
> vmlinux-objs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
>
> -vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o
> +vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o \
> + $(obj)/sl_main.o $(obj)/sl_stub.o
>
> $(obj)/vmlinux: $(vmlinux-objs-y) FORCE
> $(call if_changed,ld)
> diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
> index 1dcb794c5479..803c9e2e6d85 100644
> --- a/arch/x86/boot/compressed/head_64.S
> +++ b/arch/x86/boot/compressed/head_64.S
> @@ -420,6 +420,13 @@ SYM_CODE_START(startup_64)
> pushq $0
> popfq
>
> +#ifdef CONFIG_SECURE_LAUNCH
> + /* Ensure the relocation region is coverd by a PMR */

covered

> + movq %rbx, %rdi
> + movl $(_bss - startup_32), %esi
> + callq sl_check_region
> +#endif
> +
> /*
> * Copy the compressed kernel to the end of our buffer
> * where decompression in place becomes safe.
> @@ -462,6 +469,29 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
> shrq $3, %rcx
> rep stosq
>
> +#ifdef CONFIG_SECURE_LAUNCH
> + /*
> + * Have to do the final early sl stub work in 64b area.
> + *
> + * *********** NOTE ***********
> + *
> + * Several boot params get used before we get a chance to measure
> + * them in this call. This is a known issue and we currently don't
> + * have a solution. The scratch field doesn't matter. There is no
> + * obvious way to do anything about the use of kernel_alignment or
> + * init_size though these seem low risk with all the PMR and overlap
> + * checks in place.
> + */
> + movq %r15, %rdi
> + callq sl_main
> +
> + /* Ensure the decompression location is covered by a PMR */
> + movq %rbp, %rdi
> + movq output_len(%rip), %rsi
> + callq sl_check_region
> +#endif
> +
> + pushq %rsi

This looks like a rebase error.

> call load_stage2_idt
>
> /* Pass boot_params to initialize_identity_maps() */
> diff --git a/arch/x86/boot/compressed/kernel_info.S b/arch/x86/boot/compressed/kernel_info.S
> index c18f07181dd5..e199b87764e9 100644
> --- a/arch/x86/boot/compressed/kernel_info.S
> +++ b/arch/x86/boot/compressed/kernel_info.S
> @@ -28,6 +28,40 @@ SYM_DATA_START(kernel_info)
> /* Maximal allowed type for setup_data and setup_indirect structs. */
> .long SETUP_TYPE_MAX
>
> + /* Offset to the MLE header structure */
> +#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
> + .long rva(mle_header)

... so this could just be mle_header - kernel_info, and the consumer
can do the math instead.

> +#else
> + .long 0
> +#endif
> +
> kernel_info_var_len_data:
> /* Empty for time being... */
> SYM_DATA_END_LABEL(kernel_info, SYM_L_LOCAL, kernel_info_end)
> +
> +#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
> + /*
> + * The MLE Header per the TXT Specification, section 2.1
> + * MLE capabilities, see table 4. Capabilities set:
> + * bit 0: Support for GETSEC[WAKEUP] for RLP wakeup
> + * bit 1: Support for RLP wakeup using MONITOR address
> + * bit 2: The ECX register will contain the pointer to the MLE page table
> + * bit 5: TPM 1.2 family: Details/authorities PCR usage support
> + * bit 9: Supported format of TPM 2.0 event log - TCG compliant
> + */
> +SYM_DATA_START(mle_header)
> + .long 0x9082ac5a /* UUID0 */
> + .long 0x74a7476f /* UUID1 */
> + .long 0xa2555c0f /* UUID2 */
> + .long 0x42b651cb /* UUID3 */
> + .long 0x00000034 /* MLE header size */
> + .long 0x00020002 /* MLE version 2.2 */
> + .long rva(sl_stub_entry) /* Linear entry point of MLE (virt. address) */

and these should perhaps be relative to mle_header?

> + .long 0x00000000 /* First valid page of MLE */
> + .long 0x00000000 /* Offset within binary of first byte of MLE */
> + .long rva(_edata) /* Offset within binary of last byte + 1 of MLE */

and here

> + .long 0x00000227 /* Bit vector of MLE-supported capabilities */
> + .long 0x00000000 /* Starting linear address of command line (unused) */
> + .long 0x00000000 /* Ending linear address of command line (unused) */
> +SYM_DATA_END(mle_header)
> +#endif
> diff --git a/arch/x86/boot/compressed/sl_main.c b/arch/x86/boot/compressed/sl_main.c
> new file mode 100644
> index 000000000000..61e9baf410fd
> --- /dev/null
> +++ b/arch/x86/boot/compressed/sl_main.c
> @@ -0,0 +1,577 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Secure Launch early measurement and validation routines.
> + *
> + * Copyright (c) 2024, Oracle and/or its affiliates.
> + */
> +
> +#include <linux/init.h>
> +#include <linux/string.h>
> +#include <linux/linkage.h>
> +#include <asm/segment.h>
> +#include <asm/boot.h>
> +#include <asm/msr.h>
> +#include <asm/mtrr.h>
> +#include <asm/processor-flags.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/bootparam.h>
> +#include <asm/bootparam_utils.h>
> +#include <linux/slr_table.h>
> +#include <linux/slaunch.h>
> +#include <crypto/sha1.h>
> +#include <crypto/sha2.h>
> +
> +#define CAPS_VARIABLE_MTRR_COUNT_MASK 0xff
> +
> +#define SL_TPM12_LOG 1
> +#define SL_TPM20_LOG 2
> +
> +#define SL_TPM20_MAX_ALGS 2
> +
> +#define SL_MAX_EVENT_DATA 64
> +#define SL_TPM12_LOG_SIZE (sizeof(struct tcg_pcr_event) + \
> + SL_MAX_EVENT_DATA)
> +#define SL_TPM20_LOG_SIZE (sizeof(struct tcg_pcr_event2_head) + \
> + SHA1_DIGEST_SIZE + SHA256_DIGEST_SIZE + \
> + sizeof(struct tcg_event_field) + \
> + SL_MAX_EVENT_DATA)
> +
> +static void *evtlog_base;
> +static u32 evtlog_size;
> +static struct txt_heap_event_log_pointer2_1_element *log20_elem;
> +static u32 tpm_log_ver = SL_TPM12_LOG;
> +static struct tcg_efi_specid_event_algs tpm_algs[SL_TPM20_MAX_ALGS] = {0};
> +
> +extern u32 sl_cpu_type;
> +extern u32 sl_mle_start;
> +
> +static u64 sl_txt_read(u32 reg)
> +{
> + return readq((void *)(u64)(TXT_PRIV_CONFIG_REGS_BASE + reg));
> +}
> +
> +static void sl_txt_write(u32 reg, u64 val)
> +{
> + writeq(val, (void *)(u64)(TXT_PRIV_CONFIG_REGS_BASE + reg));
> +}
> +
> +static void __noreturn sl_txt_reset(u64 error)
> +{
> + /* Reading the E2STS register acts as a barrier for TXT registers */
> + sl_txt_write(TXT_CR_ERRORCODE, error);
> + sl_txt_read(TXT_CR_E2STS);
> + sl_txt_write(TXT_CR_CMD_UNLOCK_MEM_CONFIG, 1);
> + sl_txt_read(TXT_CR_E2STS);
> + sl_txt_write(TXT_CR_CMD_RESET, 1);
> +
> + for ( ; ; )
> + asm volatile ("hlt");
> +
> + unreachable();
> +}
> +
> +static u64 sl_rdmsr(u32 reg)
> +{
> + u64 lo, hi;
> +
> + asm volatile ("rdmsr" : "=a" (lo), "=d" (hi) : "c" (reg));
> +
> + return (hi << 32) | lo;
> +}
> +
> +static struct slr_table *sl_locate_and_validate_slrt(void)
> +{
> + struct txt_os_mle_data *os_mle_data;
> + struct slr_table *slrt;
> + void *txt_heap;
> +
> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
> + os_mle_data = txt_os_mle_data_start(txt_heap);
> +
> + if (!os_mle_data->slrt)
> + sl_txt_reset(SL_ERROR_INVALID_SLRT);
> +
> + slrt = (struct slr_table *)os_mle_data->slrt;
> +
> + if (slrt->magic != SLR_TABLE_MAGIC)
> + sl_txt_reset(SL_ERROR_INVALID_SLRT);
> +
> + if (slrt->architecture != SLR_INTEL_TXT)
> + sl_txt_reset(SL_ERROR_INVALID_SLRT);
> +
> + return slrt;
> +}
> +
> +static void sl_check_pmr_coverage(void *base, u32 size, bool allow_hi)
> +{
> + struct txt_os_sinit_data *os_sinit_data;
> + void *end = base + size;
> + void *txt_heap;
> +
> + if (!(sl_cpu_type & SL_CPU_INTEL))
> + return;
> +
> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
> + os_sinit_data = txt_os_sinit_data_start(txt_heap);
> +
> + if ((end >= (void *)0x100000000ULL) && (base < (void *)0x100000000ULL))
> + sl_txt_reset(SL_ERROR_REGION_STRADDLE_4GB);
> +
> + /*
> + * Note that the late stub code validates that the hi PMR covers
> + * all memory above 4G. At this point the code can only check that
> + * regions are within the hi PMR but that is sufficient.
> + */
> + if ((end > (void *)0x100000000ULL) && (base >= (void *)0x100000000ULL)) {

Better to put the cast on the pointers, given that we are doing
arithmetic, and use SZ_4G instead of open coding this constant 4
times.



> + if (allow_hi) {
> + if (end >= (void *)(os_sinit_data->vtd_pmr_hi_base +
> + os_sinit_data->vtd_pmr_hi_size))
> + sl_txt_reset(SL_ERROR_BUFFER_BEYOND_PMR);
> + } else {
> + sl_txt_reset(SL_ERROR_REGION_ABOVE_4GB);
> + }
> + }
> +
> + if (end >= (void *)os_sinit_data->vtd_pmr_lo_size)
> + sl_txt_reset(SL_ERROR_BUFFER_BEYOND_PMR);
> +}
> +
> +/*
> + * Some MSRs are modified by the pre-launch code including the MTRRs.
> + * The early MLE code has to restore these values. This code validates
> + * the values after they are measured.
> + */
> +static void sl_txt_validate_msrs(struct txt_os_mle_data *os_mle_data)
> +{
> + struct slr_txt_mtrr_state *saved_bsp_mtrrs;
> + u64 mtrr_caps, mtrr_def_type, mtrr_var;
> + struct slr_entry_intel_info *txt_info;
> + u64 misc_en_msr;
> + u32 vcnt, i;
> +
> + txt_info = (struct slr_entry_intel_info *)os_mle_data->txt_info;
> + saved_bsp_mtrrs = &txt_info->saved_bsp_mtrrs;
> +
> + mtrr_caps = sl_rdmsr(MSR_MTRRcap);
> + vcnt = (u32)(mtrr_caps & CAPS_VARIABLE_MTRR_COUNT_MASK);
> +
> + if (saved_bsp_mtrrs->mtrr_vcnt > vcnt)
> + sl_txt_reset(SL_ERROR_MTRR_INV_VCNT);
> + if (saved_bsp_mtrrs->mtrr_vcnt > TXT_OS_MLE_MAX_VARIABLE_MTRRS)
> + sl_txt_reset(SL_ERROR_MTRR_INV_VCNT);
> +
> + mtrr_def_type = sl_rdmsr(MSR_MTRRdefType);
> + if (saved_bsp_mtrrs->default_mem_type != mtrr_def_type)
> + sl_txt_reset(SL_ERROR_MTRR_INV_DEF_TYPE);
> +
> + for (i = 0; i < saved_bsp_mtrrs->mtrr_vcnt; i++) {
> + mtrr_var = sl_rdmsr(MTRRphysBase_MSR(i));
> + if (saved_bsp_mtrrs->mtrr_pair[i].mtrr_physbase != mtrr_var)
> + sl_txt_reset(SL_ERROR_MTRR_INV_BASE);
> + mtrr_var = sl_rdmsr(MTRRphysMask_MSR(i));
> + if (saved_bsp_mtrrs->mtrr_pair[i].mtrr_physmask != mtrr_var)
> + sl_txt_reset(SL_ERROR_MTRR_INV_MASK);
> + }
> +
> + misc_en_msr = sl_rdmsr(MSR_IA32_MISC_ENABLE);
> + if (txt_info->saved_misc_enable_msr != misc_en_msr)
> + sl_txt_reset(SL_ERROR_MSR_INV_MISC_EN);
> +}
> +
> +static void sl_find_drtm_event_log(struct slr_table *slrt)
> +{
> + struct txt_os_sinit_data *os_sinit_data;
> + struct slr_entry_log_info *log_info;
> + void *txt_heap;
> +
> + log_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_LOG_INFO);
> + if (!log_info)
> + sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
> +
> + evtlog_base = (void *)log_info->addr;
> + evtlog_size = log_info->size;
> +
> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
> +
> + /*
> + * For TPM 2.0, the event log 2.1 extended data structure has to also
> + * be located and fixed up.
> + */
> + os_sinit_data = txt_os_sinit_data_start(txt_heap);
> +
> + /*
> + * Only support version 6 and later that properly handle the
> + * list of ExtDataElements in the OS-SINIT structure.
> + */
> + if (os_sinit_data->version < 6)
> + sl_txt_reset(SL_ERROR_OS_SINIT_BAD_VERSION);
> +
> + /* Find the TPM2.0 logging extended heap element */
> + log20_elem = tpm20_find_log2_1_element(os_sinit_data);
> +
> + /* If found, this implies TPM20 log and family */
> + if (log20_elem)
> + tpm_log_ver = SL_TPM20_LOG;
> +}
> +
> +static void sl_validate_event_log_buffer(void)
> +{
> + struct txt_os_sinit_data *os_sinit_data;
> + void *txt_heap, *txt_end;
> + void *mle_base, *mle_end;
> + void *evtlog_end;
> +
> + if ((u64)evtlog_size > (LLONG_MAX - (u64)evtlog_base))
> + sl_txt_reset(SL_ERROR_INTEGER_OVERFLOW);
> + evtlog_end = evtlog_base + evtlog_size;
> +
> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
> + txt_end = txt_heap + sl_txt_read(TXT_CR_HEAP_SIZE);
> + os_sinit_data = txt_os_sinit_data_start(txt_heap);
> +
> + mle_base = (void *)(u64)sl_mle_start;
> + mle_end = mle_base + os_sinit_data->mle_size;
> +
> + /*
> + * This check is to ensure the event log buffer does not overlap with
> + * the MLE image.
> + */
> + if (evtlog_base >= mle_end && evtlog_end > mle_end)
> + goto pmr_check; /* above */
> +
> + if (evtlog_end <= mle_base && evtlog_base < mle_base)
> + goto pmr_check; /* below */
> +
> + sl_txt_reset(SL_ERROR_MLE_BUFFER_OVERLAP);
> +
> +pmr_check:
> + /*
> + * The TXT heap is protected by the DPR. If the TPM event log is
> + * inside the TXT heap, there is no need for a PMR check.
> + */
> + if (evtlog_base > txt_heap && evtlog_end < txt_end)
> + return;
> +
> + sl_check_pmr_coverage(evtlog_base, evtlog_size, true);
> +}
> +
> +static void sl_find_event_log_algorithms(void)
> +{
> + struct tcg_efi_specid_event_head *efi_head =
> + (struct tcg_efi_specid_event_head *)(evtlog_base +
> + log20_elem->first_record_offset +
> + sizeof(struct tcg_pcr_event));
> +
> + if (efi_head->num_algs == 0 || efi_head->num_algs > 2)
> + sl_txt_reset(SL_ERROR_TPM_NUMBER_ALGS);
> +
> + memcpy(&tpm_algs[0], &efi_head->digest_sizes[0],
> + sizeof(struct tcg_efi_specid_event_algs) * efi_head->num_algs);
> +}
> +
> +static void sl_tpm12_log_event(u32 pcr, u32 event_type,
> + const u8 *data, u32 length,
> + const u8 *event_data, u32 event_size)
> +{
> + u8 sha1_hash[SHA1_DIGEST_SIZE] = {0};
> + u8 log_buf[SL_TPM12_LOG_SIZE] = {0};
> + struct tcg_pcr_event *pcr_event;
> + u32 total_size;
> +
> + pcr_event = (struct tcg_pcr_event *)log_buf;
> + pcr_event->pcr_idx = pcr;
> + pcr_event->event_type = event_type;
> + if (length > 0) {
> + sha1(data, length, &sha1_hash[0]);
> + memcpy(&pcr_event->digest[0], &sha1_hash[0], SHA1_DIGEST_SIZE);
> + }
> + pcr_event->event_size = event_size;
> + if (event_size > 0)
> + memcpy((u8 *)pcr_event + sizeof(struct tcg_pcr_event),
> + event_data, event_size);
> +
> + total_size = sizeof(struct tcg_pcr_event) + event_size;
> +
> + if (tpm12_log_event(evtlog_base, evtlog_size, total_size, pcr_event))
> + sl_txt_reset(SL_ERROR_TPM_LOGGING_FAILED);
> +}
> +
> +static void sl_tpm20_log_event(u32 pcr, u32 event_type,
> + const u8 *data, u32 length,
> + const u8 *event_data, u32 event_size)
> +{
> + u8 sha256_hash[SHA256_DIGEST_SIZE] = {0};
> + u8 sha1_hash[SHA1_DIGEST_SIZE] = {0};
> + u8 log_buf[SL_TPM20_LOG_SIZE] = {0};
> + struct sha256_state sctx256 = {0};
> + struct tcg_pcr_event2_head *head;
> + struct tcg_event_field *event;
> + u32 total_size;
> + u16 *alg_ptr;
> + u8 *dgst_ptr;
> +
> + head = (struct tcg_pcr_event2_head *)log_buf;
> + head->pcr_idx = pcr;
> + head->event_type = event_type;
> + total_size = sizeof(struct tcg_pcr_event2_head);
> + alg_ptr = (u16 *)(log_buf + sizeof(struct tcg_pcr_event2_head));
> +
> + for ( ; head->count < 2; head->count++) {
> + if (!tpm_algs[head->count].alg_id)
> + break;
> +
> + *alg_ptr = tpm_algs[head->count].alg_id;
> + dgst_ptr = (u8 *)alg_ptr + sizeof(u16);
> +
> + if (tpm_algs[head->count].alg_id == TPM_ALG_SHA256 &&
> + length) {
> + sha256_init(&sctx256);
> + sha256_update(&sctx256, data, length);
> + sha256_final(&sctx256, &sha256_hash[0]);
> + } else if (tpm_algs[head->count].alg_id == TPM_ALG_SHA1 &&
> + length) {
> + sha1(data, length, &sha1_hash[0]);
> + }
> +
> + if (tpm_algs[head->count].alg_id == TPM_ALG_SHA256) {
> + memcpy(dgst_ptr, &sha256_hash[0], SHA256_DIGEST_SIZE);
> + total_size += SHA256_DIGEST_SIZE + sizeof(u16);
> + alg_ptr = (u16 *)((u8 *)alg_ptr + SHA256_DIGEST_SIZE + sizeof(u16));
> + } else if (tpm_algs[head->count].alg_id == TPM_ALG_SHA1) {
> + memcpy(dgst_ptr, &sha1_hash[0], SHA1_DIGEST_SIZE);
> + total_size += SHA1_DIGEST_SIZE + sizeof(u16);
> + alg_ptr = (u16 *)((u8 *)alg_ptr + SHA1_DIGEST_SIZE + sizeof(u16));
> + } else {
> + sl_txt_reset(SL_ERROR_TPM_UNKNOWN_DIGEST);
> + }
> + }
> +
> + event = (struct tcg_event_field *)(log_buf + total_size);
> + event->event_size = event_size;
> + if (event_size > 0)
> + memcpy((u8 *)event + sizeof(struct tcg_event_field), event_data, event_size);
> + total_size += sizeof(struct tcg_event_field) + event_size;
> +
> + if (tpm20_log_event(log20_elem, evtlog_base, evtlog_size, total_size, &log_buf[0]))
> + sl_txt_reset(SL_ERROR_TPM_LOGGING_FAILED);
> +}
> +
> +static void sl_tpm_extend_evtlog(u32 pcr, u32 type,
> + const u8 *data, u32 length, const char *desc)
> +{
> + if (tpm_log_ver == SL_TPM20_LOG)
> + sl_tpm20_log_event(pcr, type, data, length,
> + (const u8 *)desc, strlen(desc));
> + else
> + sl_tpm12_log_event(pcr, type, data, length,
> + (const u8 *)desc, strlen(desc));
> +}
> +
> +static struct setup_data *sl_handle_setup_data(struct setup_data *curr,
> + struct slr_policy_entry *entry)
> +{
> + struct setup_indirect *ind;
> + struct setup_data *next;
> +
> + if (!curr)
> + return NULL;
> +
> + next = (struct setup_data *)(unsigned long)curr->next;
> +
> + /* SETUP_INDIRECT instances have to be handled differently */
> + if (curr->type == SETUP_INDIRECT) {
> + ind = (struct setup_indirect *)((u8 *)curr + offsetof(struct setup_data, data));
> +
> + sl_check_pmr_coverage((void *)ind->addr, ind->len, true);
> +
> + sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
> + (void *)ind->addr, ind->len,
> + entry->evt_info);
> +
> + return next;
> + }
> +
> + sl_check_pmr_coverage(((u8 *)curr) + sizeof(struct setup_data),
> + curr->len, true);
> +
> + sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
> + ((u8 *)curr) + sizeof(struct setup_data),
> + curr->len,
> + entry->evt_info);
> +
> + return next;
> +}
> +
> +static void sl_extend_setup_data(struct slr_policy_entry *entry)
> +{
> + struct setup_data *data;
> +
> + /*
> + * Measuring the boot params measured the fixed e820 memory map.
> + * Measure any setup_data entries including e820 extended entries.
> + */
> + data = (struct setup_data *)(unsigned long)entry->entity;
> + while (data)
> + data = sl_handle_setup_data(data, entry);
> +}
> +
> +static void sl_extend_slrt(struct slr_policy_entry *entry)
> +{
> + struct slr_table *slrt = (struct slr_table *)entry->entity;
> + struct slr_entry_intel_info *intel_info;
> +
> + /*
> + * In revision one of the SLRT, the only table that needs to be
> + * measured is the Intel info table. Everything else is meta-data,
> + * addresses and sizes. Note the size of what to measure is not set.
> + * The flag SLR_POLICY_IMPLICIT_SIZE leaves it to the measuring code
> + * to sort out.
> + */
> + if (slrt->revision == 1) {
> + intel_info = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_INTEL_INFO);
> + if (!intel_info)
> + sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
> +
> + sl_tpm_extend_evtlog(entry->pcr, TXT_EVTYPE_SLAUNCH,
> + (void *)entry->entity, sizeof(struct slr_entry_intel_info),
> + entry->evt_info);
> + }
> +}
> +
> +static void sl_extend_txt_os2mle(struct slr_policy_entry *entry)
> +{
> + struct txt_os_mle_data *os_mle_data;
> + void *txt_heap;
> +
> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
> + os_mle_data = txt_os_mle_data_start(txt_heap);
> +
> + /*
> + * Version 1 of the OS-MLE heap structure has no fields to measure. It just
> + * has addresses and sizes and a scratch buffer.
> + */
> + if (os_mle_data->version == 1)
> + return;
> +}
> +
> +static void sl_process_extend_policy(struct slr_table *slrt)
> +{
> + struct slr_entry_policy *policy;
> + u16 i;
> +
> + policy = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_ENTRY_POLICY);
> + if (!policy)
> + sl_txt_reset(SL_ERROR_SLRT_MISSING_ENTRY);
> +
> + for (i = 0; i < policy->nr_entries; i++) {
> + switch (policy->policy_entries[i].entity_type) {
> + case SLR_ET_SETUP_DATA:
> + sl_extend_setup_data(&policy->policy_entries[i]);
> + break;
> + case SLR_ET_SLRT:
> + sl_extend_slrt(&policy->policy_entries[i]);
> + break;
> + case SLR_ET_TXT_OS2MLE:
> + sl_extend_txt_os2mle(&policy->policy_entries[i]);
> + break;
> + case SLR_ET_UNUSED:
> + continue;
> + default:
> + sl_tpm_extend_evtlog(policy->policy_entries[i].pcr, TXT_EVTYPE_SLAUNCH,
> + (void *)policy->policy_entries[i].entity,
> + policy->policy_entries[i].size,
> + policy->policy_entries[i].evt_info);
> + }
> + }
> +}
> +
> +static void sl_process_extend_uefi_config(struct slr_table *slrt)
> +{
> + struct slr_entry_uefi_config *uefi_config;
> + u16 i;
> +
> + uefi_config = slr_next_entry_by_tag(slrt, NULL, SLR_ENTRY_UEFI_CONFIG);
> +
> + /* Optionally here depending on how SL kernel was booted */
> + if (!uefi_config)
> + return;
> +
> + for (i = 0; i < uefi_config->nr_entries; i++) {
> + sl_tpm_extend_evtlog(uefi_config->uefi_cfg_entries[i].pcr, TXT_EVTYPE_SLAUNCH,
> + (void *)uefi_config->uefi_cfg_entries[i].cfg,
> + uefi_config->uefi_cfg_entries[i].size,
> + uefi_config->uefi_cfg_entries[i].evt_info);
> + }
> +}
> +
> +asmlinkage __visible void sl_check_region(void *base, u32 size)
> +{
> + sl_check_pmr_coverage(base, size, false);
> +}
> +
> +asmlinkage __visible void sl_main(void *bootparams)
> +{
> + struct boot_params *bp = (struct boot_params *)bootparams;
> + struct txt_os_mle_data *os_mle_data;
> + struct slr_table *slrt;
> + void *txt_heap;
> +
> + /*
> + * Ensure loadflags do not indicate a secure launch was done
> + * unless it really was.
> + */
> + bp->hdr.loadflags &= ~SLAUNCH_FLAG;
> +
> + /*
> + * Currently only Intel TXT is supported for Secure Launch. Testing
> + * this value also indicates that the kernel was booted successfully
> + * through the Secure Launch entry point and is in SMX mode.
> + */
> + if (!(sl_cpu_type & SL_CPU_INTEL))
> + return;
> +
> + slrt = sl_locate_and_validate_slrt();
> +
> + /* Locate the TPM event log. */
> + sl_find_drtm_event_log(slrt);
> +
> + /* Validate the location of the event log buffer before using it */
> + sl_validate_event_log_buffer();
> +
> + /*
> + * Find the TPM hash algorithms used by the ACM and recorded in the
> + * event log.
> + */
> + if (tpm_log_ver == SL_TPM20_LOG)
> + sl_find_event_log_algorithms();
> +
> + /*
> + * Sanitize them before measuring. Set the SLAUNCH_FLAG early since if
> + * anything fails, the system will reset anyway.
> + */
> + sanitize_boot_params(bp);
> + bp->hdr.loadflags |= SLAUNCH_FLAG;
> +
> + sl_check_pmr_coverage(bootparams, PAGE_SIZE, false);
> +
> + /* Place event log SL specific tags before and after measurements */
> + sl_tpm_extend_evtlog(17, TXT_EVTYPE_SLAUNCH_START, NULL, 0, "");
> +
> + /* Process all policy entries and extend the measurements to the evtlog */
> + sl_process_extend_policy(slrt);
> +
> + /* Process all EFI config entries and extend the measurements to the evtlog */
> + sl_process_extend_uefi_config(slrt);
> +
> + sl_tpm_extend_evtlog(17, TXT_EVTYPE_SLAUNCH_END, NULL, 0, "");
> +
> + /* No PMR check is needed, the TXT heap is covered by the DPR */
> + txt_heap = (void *)sl_txt_read(TXT_CR_HEAP_BASE);
> + os_mle_data = txt_os_mle_data_start(txt_heap);
> +
> + /*
> + * Now that the OS-MLE data is measured, ensure the MTRR and
> + * misc enable MSRs are what we expect.
> + */
> + sl_txt_validate_msrs(os_mle_data);
> +}
> diff --git a/arch/x86/boot/compressed/sl_stub.S b/arch/x86/boot/compressed/sl_stub.S
> new file mode 100644
> index 000000000000..24b8f23d5dcc
> --- /dev/null
> +++ b/arch/x86/boot/compressed/sl_stub.S
> @@ -0,0 +1,725 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +/*
> + * Secure Launch protected mode entry point.
> + *
> + * Copyright (c) 2024, Oracle and/or its affiliates.
> + */
> + .code32
> + .text
> +#include <linux/linkage.h>
> +#include <asm/segment.h>
> +#include <asm/msr.h>
> +#include <asm/apicdef.h>
> +#include <asm/trapnr.h>
> +#include <asm/processor-flags.h>
> +#include <asm/asm-offsets.h>
> +#include <asm/bootparam.h>
> +#include <asm/page_types.h>
> +#include <asm/irq_vectors.h>
> +#include <linux/slr_table.h>
> +#include <linux/slaunch.h>
> +
> +/* CPUID: leaf 1, ECX, SMX feature bit */
> +#define X86_FEATURE_BIT_SMX (1 << 6)
> +
> +#define IDT_VECTOR_LO_BITS 0
> +#define IDT_VECTOR_HI_BITS 6
> +
> +/*
> + * See the comment in head_64.S for detailed information on what this macro
> + * and others like it are used for. The comment appears right at the top of
> + * the file.
> + */
> +#define rva(X) ((X) - sl_stub_entry)
> +
> +/*
> + * The GETSEC op code is open coded because older versions of
> + * GCC do not support the getsec mnemonic.
> + */
> +.macro GETSEC leaf
> + pushl %ebx
> + xorl %ebx, %ebx /* Must be zero for SMCTRL */
> + movl \leaf, %eax /* Leaf function */
> + .byte 0x0f, 0x37 /* GETSEC opcode */
> + popl %ebx
> +.endm
> +
> +.macro TXT_RESET error
> + /*
> + * Set a sticky error value and reset. Note the movs to %eax act as
> + * TXT register barriers.
> + */
> + movl \error, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ERRORCODE)
> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
> + movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_NO_SECRETS)
> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
> + movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_UNLOCK_MEM_CONFIG)
> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_E2STS), %eax
> + movl $1, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_CMD_RESET)
> +1:
> + hlt
> + jmp 1b
> +.endm
> +
> + .code32
> +SYM_FUNC_START(sl_stub_entry)
> + cli
> + cld
> +
> + /*
> + * On entry, %ebx has the entry abs offset to sl_stub_entry. This
> + * will be correctly scaled using the rva macro and avoid causing
> + * relocations. Only %cs and %ds segments are known good.

Could you please clarify this? 'scaling' is unidiomatic in this
context, and actually means something different in my book. AIUI, %ebx
is guaranteed to carry the actual address of sl_stub_entry(), and
rva() is used to generate relative references using %ebx as a base, as
to avoid /absolute/ relocations, which would require fixups at
runtime.


> + */
> +
> + /* Load GDT, set segment regs and lret to __SL32_CS */
> + leal rva(sl_gdt_desc)(%ebx), %eax
> + addl %eax, 2(%eax)
> + lgdt (%eax)
> +
> + movl $(__SL32_DS), %eax
> + movw %ax, %ds
> + movw %ax, %es
> + movw %ax, %fs
> + movw %ax, %gs
> + movw %ax, %ss
> +
> + /*
> + * Now that %ss is known good, take the first stack for the BSP. The
> + * AP stacks are only used on Intel.
> + */
> + leal rva(sl_stacks_end)(%ebx), %esp
> +
> + leal rva(.Lsl_cs)(%ebx), %eax
> + pushl $(__SL32_CS)
> + pushl %eax
> + lret
> +
> +.Lsl_cs:
> + /* Save our base pointer reg and page table for MLE */
> + pushl %ebx
> + pushl %ecx
> +
> + /* See if SMX feature is supported. */
> + movl $1, %eax
> + cpuid
> + testl $(X86_FEATURE_BIT_SMX), %ecx
> + jz .Ldo_unknown_cpu
> +
> + popl %ecx
> + popl %ebx
> +
> + /* Know it is Intel */
> + movl $(SL_CPU_INTEL), rva(sl_cpu_type)(%ebx)
> +
> + /* Locate the base of the MLE using the page tables in %ecx */
> + call sl_find_mle_base
> +
> + /* Increment CPU count for BSP */
> + incl rva(sl_txt_cpu_count)(%ebx)
> +
> + /*
> + * Enable SMI with GETSEC[SMCTRL] which were disabled by SENTER.
> + * NMIs were also disabled by SENTER. Since there is no IDT for the BSP,
> + * allow the mainline kernel re-enable them in the normal course of
> + * booting.
> + */
> + GETSEC $(SMX_X86_GETSEC_SMCTRL)
> +
> + /* Clear the TXT error registers for a clean start of day */
> + movl $0, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ERRORCODE)
> + movl $0xffffffff, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_ESTS)
> +
> + /* On Intel, the zero page address is passed in the TXT heap */
> + /* Read physical base of heap into EAX */
> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
> + /* Read the size of the BIOS data into ECX (first 8 bytes) */
> + movl (%eax), %ecx
> + /* Skip over BIOS data and size of OS to MLE data section */
> + leal 8(%eax, %ecx), %eax
> +
> + /* Need to verify the values in the OS-MLE struct passed in */
> + call sl_txt_verify_os_mle_struct
> +
> + /*
> + * Get the boot params address from the heap. Note %esi and %ebx MUST
> + * be preserved across calls and operations.
> + */
> + movl SL_boot_params_addr(%eax), %esi
> +
> + /* Save %ebx so the APs can find their way home */
> + movl %ebx, (SL_mle_scratch + SL_SCRATCH_AP_EBX)(%eax)
> +
> + /* Fetch the AP wake code block address from the heap */
> + movl SL_ap_wake_block(%eax), %edi
> + movl %edi, rva(sl_txt_ap_wake_block)(%ebx)
> +
> + /* Store the offset in the AP wake block to the jmp address */
> + movl $(sl_ap_jmp_offset - sl_txt_ap_wake_begin), \
> + (SL_mle_scratch + SL_SCRATCH_AP_JMP_OFFSET)(%eax)
> +
> + /* Store the offset in the AP wake block to the AP stacks block */
> + movl $(sl_stacks - sl_txt_ap_wake_begin), \
> + (SL_mle_scratch + SL_SCRATCH_AP_STACKS_OFFSET)(%eax)
> +
> + /* %eax still is the base of the OS-MLE block, save it */
> + pushl %eax
> +
> + /* Relocate the AP wake code to the safe block */
> + call sl_txt_reloc_ap_wake
> +
> + /*
> + * Wake up all APs that are blocked in the ACM and wait for them to
> + * halt. This should be done before restoring the MTRRs so the ACM is
> + * still properly in WB memory.
> + */
> + call sl_txt_wake_aps
> +
> + /* Restore OS-MLE in %eax */
> + popl %eax
> +
> + /*
> + * %edi is used by this routine to find the MTRRs which are in the SLRT
> + * in the Intel info.
> + */
> + movl SL_txt_info(%eax), %edi
> + call sl_txt_load_regs
> +
> + jmp .Lcpu_setup_done
> +
> +.Ldo_unknown_cpu:
> + /* Non-Intel CPUs are not yet supported */
> + ud2
> +
> +.Lcpu_setup_done:
> + /*
> + * Don't enable MCE at this point. The kernel will enable
> + * it on the BSP later when it is ready.
> + */
> +
> + /* Done, jump to normal 32b pm entry */
> + jmp startup_32
> +SYM_FUNC_END(sl_stub_entry)
> +
> +SYM_FUNC_START(sl_find_mle_base)
> + /* %ecx has PDPT, get first PD */
> + movl (%ecx), %eax
> + andl $(PAGE_MASK), %eax
> + /* Get first PT from first PDE */
> + movl (%eax), %eax
> + andl $(PAGE_MASK), %eax
> + /* Get MLE base from first PTE */
> + movl (%eax), %eax
> + andl $(PAGE_MASK), %eax
> +
> + movl %eax, rva(sl_mle_start)(%ebx)
> + ret
> +SYM_FUNC_END(sl_find_mle_base)
> +
> +SYM_FUNC_START(sl_check_buffer_mle_overlap)
> + /* %ecx: buffer begin %edx: buffer end */
> + /* %ebx: MLE begin %edi: MLE end */
> + /* %eax: region may be inside MLE */
> +
> + cmpl %edi, %ecx
> + jb .Lnext_check
> + cmpl %edi, %edx
> + jbe .Lnext_check
> + jmp .Lvalid /* Buffer above MLE */
> +
> +.Lnext_check:
> + cmpl %ebx, %edx
> + ja .Linside_check
> + cmpl %ebx, %ecx
> + jae .Linside_check
> + jmp .Lvalid /* Buffer below MLE */
> +
> +.Linside_check:
> + cmpl $0, %eax
> + jz .Linvalid
> + cmpl %ebx, %ecx
> + jb .Linvalid
> + cmpl %edi, %edx
> + ja .Linvalid
> + jmp .Lvalid /* Buffer in MLE */
> +
> +.Linvalid:
> + TXT_RESET $(SL_ERROR_MLE_BUFFER_OVERLAP)
> +
> +.Lvalid:
> + ret
> +SYM_FUNC_END(sl_check_buffer_mle_overlap)
> +
> +SYM_FUNC_START(sl_txt_verify_os_mle_struct)
> + pushl %ebx
> + /*
> + * %eax points to the base of the OS-MLE struct. Need to also
> + * read some values from the OS-SINIT struct too.
> + */
> + movl -8(%eax), %ecx
> + /* Skip over OS to MLE data section and size of OS-SINIT structure */
> + leal (%eax, %ecx), %edx
> +
> + /* Load MLE image base absolute offset */
> + movl rva(sl_mle_start)(%ebx), %ebx
> +
> + /* Verify the value of the low PMR base. It should always be 0. */
> + movl SL_vtd_pmr_lo_base(%edx), %esi
> + cmpl $0, %esi
> + jz .Lvalid_pmr_base
> + TXT_RESET $(SL_ERROR_LO_PMR_BASE)
> +
> +.Lvalid_pmr_base:
> + /* Grab some values from OS-SINIT structure */
> + movl SL_mle_size(%edx), %edi
> + addl %ebx, %edi
> + jc .Loverflow_detected
> + movl SL_vtd_pmr_lo_size(%edx), %esi
> +
> + /* Check the AP wake block */
> + movl SL_ap_wake_block(%eax), %ecx
> + movl SL_ap_wake_block_size(%eax), %edx
> + addl %ecx, %edx
> + jc .Loverflow_detected
> + pushl %eax
> + xorl %eax, %eax
> + call sl_check_buffer_mle_overlap
> + popl %eax
> + cmpl %esi, %edx
> + ja .Lbuffer_beyond_pmr
> +
> + /*
> + * Check the boot params. Note during a UEFI boot, the boot
> + * params will be inside the MLE image. Test for this case
> + * in the overlap case.
> + */
> + movl SL_boot_params_addr(%eax), %ecx
> + movl $(PAGE_SIZE), %edx
> + addl %ecx, %edx
> + jc .Loverflow_detected
> + pushl %eax
> + movl $1, %eax
> + call sl_check_buffer_mle_overlap
> + popl %eax
> + cmpl %esi, %edx
> + ja .Lbuffer_beyond_pmr
> +
> + /* Check that the AP wake block is big enough */
> + cmpl $(sl_txt_ap_wake_end - sl_txt_ap_wake_begin), \
> + SL_ap_wake_block_size(%eax)
> + jae .Lwake_block_ok
> + TXT_RESET $(SL_ERROR_WAKE_BLOCK_TOO_SMALL)
> +
> +.Lwake_block_ok:
> + popl %ebx
> + ret
> +
> +.Loverflow_detected:
> + TXT_RESET $(SL_ERROR_INTEGER_OVERFLOW)
> +
> +.Lbuffer_beyond_pmr:
> + TXT_RESET $(SL_ERROR_BUFFER_BEYOND_PMR)
> +SYM_FUNC_END(sl_txt_verify_os_mle_struct)
> +
> +SYM_FUNC_START(sl_txt_ap_entry)
> + cli
> + cld
> + /*
> + * The %cs and %ds segments are known good after waking the AP.
> + * First order of business is to find where we are and
> + * save it in %ebx.
> + */
> +
> + /* Read physical base of heap into EAX */
> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
> + /* Read the size of the BIOS data into ECX (first 8 bytes) */
> + movl (%eax), %ecx
> + /* Skip over BIOS data and size of OS to MLE data section */
> + leal 8(%eax, %ecx), %eax
> +
> + /* Saved %ebx from the BSP and stash OS-MLE pointer */
> + movl (SL_mle_scratch + SL_SCRATCH_AP_EBX)(%eax), %ebx
> +
> + /* Save TXT info ptr in %edi for call to sl_txt_load_regs */
> + movl SL_txt_info(%eax), %edi
> +
> + /* Lock and get our stack index */
> + movl $1, %ecx
> +.Lspin:
> + xorl %eax, %eax
> + lock cmpxchgl %ecx, rva(sl_txt_spin_lock)(%ebx)
> + pause
> + jnz .Lspin
> +
> + /* Increment the stack index and use the next value inside lock */
> + incl rva(sl_txt_stack_index)(%ebx)
> + movl rva(sl_txt_stack_index)(%ebx), %eax
> +
> + /* Unlock */
> + movl $0, rva(sl_txt_spin_lock)(%ebx)
> +
> + /* Location of the relocated AP wake block */
> + movl rva(sl_txt_ap_wake_block)(%ebx), %ecx
> +
> + /* Load reloc GDT, set segment regs and lret to __SL32_CS */
> + lgdt (sl_ap_gdt_desc - sl_txt_ap_wake_begin)(%ecx)
> +
> + movl $(__SL32_DS), %edx
> + movw %dx, %ds
> + movw %dx, %es
> + movw %dx, %fs
> + movw %dx, %gs
> + movw %dx, %ss
> +
> + /* Load our reloc AP stack */
> + movl $(TXT_BOOT_STACK_SIZE), %edx
> + mull %edx
> + leal (sl_stacks_end - sl_txt_ap_wake_begin)(%ecx), %esp
> + subl %eax, %esp
> +
> + /* Switch to AP code segment */
> + leal rva(.Lsl_ap_cs)(%ebx), %eax
> + pushl $(__SL32_CS)
> + pushl %eax
> + lret
> +
> +.Lsl_ap_cs:
> + /* Load the relocated AP IDT */
> + lidt (sl_ap_idt_desc - sl_txt_ap_wake_begin)(%ecx)
> +
> + /* Fixup MTRRs and misc enable MSR on APs too */
> + call sl_txt_load_regs
> +
> + /* Enable SMI with GETSEC[SMCTRL] */
> + GETSEC $(SMX_X86_GETSEC_SMCTRL)
> +
> + /* IRET-to-self can be used to enable NMIs which SENTER disabled */
> + leal rva(.Lnmi_enabled_ap)(%ebx), %eax
> + pushfl
> + pushl $(__SL32_CS)
> + pushl %eax
> + iret
> +
> +.Lnmi_enabled_ap:
> + /* Put APs in X2APIC mode like the BSP */
> + movl $(MSR_IA32_APICBASE), %ecx
> + rdmsr
> + orl $(XAPIC_ENABLE | X2APIC_ENABLE), %eax
> + wrmsr
> +
> + /*
> + * Basically done, increment the CPU count and jump off to the AP
> + * wake block to wait.
> + */
> + lock incl rva(sl_txt_cpu_count)(%ebx)
> +
> + movl rva(sl_txt_ap_wake_block)(%ebx), %eax
> + jmp *%eax
> +SYM_FUNC_END(sl_txt_ap_entry)
> +
> +SYM_FUNC_START(sl_txt_reloc_ap_wake)
> + /* Save boot params register */
> + pushl %esi
> +
> + movl rva(sl_txt_ap_wake_block)(%ebx), %edi
> +
> + /* Fixup AP IDT and GDT descriptor before relocating */
> + leal rva(sl_ap_idt_desc)(%ebx), %eax
> + addl %edi, 2(%eax)
> + leal rva(sl_ap_gdt_desc)(%ebx), %eax
> + addl %edi, 2(%eax)
> +
> + /*
> + * Copy the AP wake code and AP GDT/IDT to the protected wake block
> + * provided by the loader. Destination already in %edi.
> + */
> + movl $(sl_txt_ap_wake_end - sl_txt_ap_wake_begin), %ecx
> + leal rva(sl_txt_ap_wake_begin)(%ebx), %esi
> + rep movsb
> +
> + /* Setup the IDT for the APs to use in the relocation block */
> + movl rva(sl_txt_ap_wake_block)(%ebx), %ecx
> + addl $(sl_ap_idt - sl_txt_ap_wake_begin), %ecx
> + xorl %edx, %edx
> +
> + /* Form the default reset vector relocation address */
> + movl rva(sl_txt_ap_wake_block)(%ebx), %esi
> + addl $(sl_txt_int_reset - sl_txt_ap_wake_begin), %esi
> +
> +1:
> + cmpw $(NR_VECTORS), %dx
> + jz .Lap_idt_done
> +
> + cmpw $(X86_TRAP_NMI), %dx
> + jz 2f
> +
> + /* Load all other fixed vectors with reset handler */
> + movl %esi, %eax
> + movw %ax, (IDT_VECTOR_LO_BITS)(%ecx)
> + shrl $16, %eax
> + movw %ax, (IDT_VECTOR_HI_BITS)(%ecx)
> + jmp 3f
> +
> +2:
> + /* Load single wake NMI IPI vector at the relocation address */
> + movl rva(sl_txt_ap_wake_block)(%ebx), %eax
> + addl $(sl_txt_int_nmi - sl_txt_ap_wake_begin), %eax
> + movw %ax, (IDT_VECTOR_LO_BITS)(%ecx)
> + shrl $16, %eax
> + movw %ax, (IDT_VECTOR_HI_BITS)(%ecx)
> +
> +3:
> + incw %dx
> + addl $8, %ecx
> + jmp 1b
> +
> +.Lap_idt_done:
> + popl %esi
> + ret
> +SYM_FUNC_END(sl_txt_reloc_ap_wake)
> +
> +SYM_FUNC_START(sl_txt_load_regs)
> + /* Save base pointer register */
> + pushl %ebx
> +
> + /*
> + * On Intel, the original variable MTRRs and Misc Enable MSR are
> + * restored on the BSP at early boot. Each AP will also restore
> + * its MTRRs and Misc Enable MSR.
> + */
> + pushl %edi
> + addl $(SL_saved_bsp_mtrrs), %edi
> + movl (%edi), %ebx
> + pushl %ebx /* default_mem_type lo */
> + addl $4, %edi
> + movl (%edi), %ebx
> + pushl %ebx /* default_mem_type hi */
> + addl $4, %edi
> + movl (%edi), %ebx /* mtrr_vcnt lo, don't care about hi part */
> + addl $8, %edi /* now at MTRR pair array */
> + /* Write the variable MTRRs */
> + movl $(MSR_MTRRphysBase0), %ecx
> +1:
> + cmpl $0, %ebx
> + jz 2f
> +
> + movl (%edi), %eax /* MTRRphysBaseX lo */
> + addl $4, %edi
> + movl (%edi), %edx /* MTRRphysBaseX hi */
> + wrmsr
> + addl $4, %edi
> + incl %ecx
> + movl (%edi), %eax /* MTRRphysMaskX lo */
> + addl $4, %edi
> + movl (%edi), %edx /* MTRRphysMaskX hi */
> + wrmsr
> + addl $4, %edi
> + incl %ecx
> +
> + decl %ebx
> + jmp 1b
> +2:
> + /* Write the default MTRR register */
> + popl %edx
> + popl %eax
> + movl $(MSR_MTRRdefType), %ecx
> + wrmsr
> +
> + /* Return to beginning and write the misc enable msr */
> + popl %edi
> + addl $(SL_saved_misc_enable_msr), %edi
> + movl (%edi), %eax /* saved_misc_enable_msr lo */
> + addl $4, %edi
> + movl (%edi), %edx /* saved_misc_enable_msr hi */
> + movl $(MSR_IA32_MISC_ENABLE), %ecx
> + wrmsr
> +
> + popl %ebx
> + ret
> +SYM_FUNC_END(sl_txt_load_regs)
> +
> +SYM_FUNC_START(sl_txt_wake_aps)
> + /* Save boot params register */
> + pushl %esi
> +
> + /* First setup the MLE join structure and load it into TXT reg */
> + leal rva(sl_gdt)(%ebx), %eax
> + leal rva(sl_txt_ap_entry)(%ebx), %ecx
> + leal rva(sl_smx_rlp_mle_join)(%ebx), %edx
> + movl %eax, SL_rlp_gdt_base(%edx)
> + movl %ecx, SL_rlp_entry_point(%edx)
> + movl %edx, (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_MLE_JOIN)
> +
> + /* Another TXT heap walk to find various values needed to wake APs */
> + movl (TXT_PRIV_CONFIG_REGS_BASE + TXT_CR_HEAP_BASE), %eax
> + /* At BIOS data size, find the number of logical processors */
> + movl (SL_num_logical_procs + 8)(%eax), %edx
> + /* Skip over BIOS data */
> + movl (%eax), %ecx
> + addl %ecx, %eax
> + /* Skip over OS to MLE */
> + movl (%eax), %ecx
> + addl %ecx, %eax
> + /* At OS-SNIT size, get capabilities to know how to wake up the APs */
> + movl (SL_capabilities + 8)(%eax), %esi
> + /* Skip over OS to SNIT */
> + movl (%eax), %ecx
> + addl %ecx, %eax
> + /* At SINIT-MLE size, get the AP wake MONITOR address */
> + movl (SL_rlp_wakeup_addr + 8)(%eax), %edi
> +
> + /* Determine how to wake up the APs */
> + testl $(1 << TXT_SINIT_MLE_CAP_WAKE_MONITOR), %esi
> + jz .Lwake_getsec
> +
> + /* Wake using MWAIT MONITOR */
> + movl $1, (%edi)
> + jmp .Laps_awake
> +
> +.Lwake_getsec:
> + /* Wake using GETSEC(WAKEUP) */
> + GETSEC $(SMX_X86_GETSEC_WAKEUP)
> +
> +.Laps_awake:
> + /*
> + * All of the APs are woken up and rendesvous in the relocated wake
> + * block starting at sl_txt_ap_wake_begin. Wait for all of them to
> + * halt.
> + */
> + pause
> + cmpl rva(sl_txt_cpu_count)(%ebx), %edx
> + jne .Laps_awake
> +
> + popl %esi
> + ret
> +SYM_FUNC_END(sl_txt_wake_aps)
> +
> +/* This is the beginning of the relocated AP wake code block */
> + .global sl_txt_ap_wake_begin
> +sl_txt_ap_wake_begin:
> +
> + /* Get the LAPIC ID for each AP and stash it on the stack */
> + movl $(MSR_IA32_X2APIC_APICID), %ecx
> + rdmsr
> + pushl %eax
> +
> + /*
> + * Get a pointer to the monitor location on this APs stack to test below
> + * after mwait returns. Currently %esp points to just past the pushed APIC
> + * ID value.
> + */
> + movl %esp, %eax
> + subl $(TXT_BOOT_STACK_SIZE - 4), %eax
> + movl $0, (%eax)
> +
> + /* Clear ecx/edx so no invalid extensions or hints are passed to monitor */
> + xorl %ecx, %ecx
> + xorl %edx, %edx
> +
> + /*
> + * Arm the monitor and wait for it to be poked by he SMP bringup code. The mwait
> + * instruction can return for a number of reasons. Test to see if it returned
> + * because the monitor was written to.
> + */
> + monitor
> +
> +1:
> + mfence
> + mwait
> + movl (%eax), %edx
> + testl %edx, %edx
> + jz 1b
> +
> + /*
> + * This is the long absolute jump to the 32b Secure Launch protected mode stub
> + * code in sl_trampoline_start32() in the rmpiggy. The jump address will be
> + * fixed in the SMP boot code when the first AP is brought up. This whole area
> + * is provided and protected in the memory map by the prelaunch code.
> + */
> + .byte 0xea
> +sl_ap_jmp_offset:
> + .long 0x00000000
> + .word __SL32_CS
> +
> +SYM_FUNC_START(sl_txt_int_nmi)
> + /* NMI context, just IRET */
> + iret
> +SYM_FUNC_END(sl_txt_int_nmi)
> +
> +SYM_FUNC_START(sl_txt_int_reset)
> + TXT_RESET $(SL_ERROR_INV_AP_INTERRUPT)
> +SYM_FUNC_END(sl_txt_int_reset)
> +
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_ap_idt_desc)
> + .word sl_ap_idt_end - sl_ap_idt - 1 /* Limit */
> + .long sl_ap_idt - sl_txt_ap_wake_begin /* Base */
> +SYM_DATA_END_LABEL(sl_ap_idt_desc, SYM_L_LOCAL, sl_ap_idt_desc_end)
> +
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_ap_idt)
> + .rept NR_VECTORS
> + .word 0x0000 /* Offset 15 to 0 */
> + .word __SL32_CS /* Segment selector */
> + .word 0x8e00 /* Present, DPL=0, 32b Vector, Interrupt */
> + .word 0x0000 /* Offset 31 to 16 */
> + .endr
> +SYM_DATA_END_LABEL(sl_ap_idt, SYM_L_LOCAL, sl_ap_idt_end)
> +
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_ap_gdt_desc)
> + .word sl_ap_gdt_end - sl_ap_gdt - 1
> + .long sl_ap_gdt - sl_txt_ap_wake_begin
> +SYM_DATA_END_LABEL(sl_ap_gdt_desc, SYM_L_LOCAL, sl_ap_gdt_desc_end)
> +
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_ap_gdt)
> + .quad 0x0000000000000000 /* NULL */
> + .quad 0x00cf9a000000ffff /* __SL32_CS */
> + .quad 0x00cf92000000ffff /* __SL32_DS */
> +SYM_DATA_END_LABEL(sl_ap_gdt, SYM_L_LOCAL, sl_ap_gdt_end)
> +
> + /* Small stacks for BSP and APs to work with */
> + .balign 64
> +SYM_DATA_START_LOCAL(sl_stacks)
> + .fill (TXT_MAX_CPUS * TXT_BOOT_STACK_SIZE), 1, 0
> +SYM_DATA_END_LABEL(sl_stacks, SYM_L_LOCAL, sl_stacks_end)
> +
> +/* This is the end of the relocated AP wake code block */
> + .global sl_txt_ap_wake_end
> +sl_txt_ap_wake_end:
> +
> + .data
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_gdt_desc)
> + .word sl_gdt_end - sl_gdt - 1
> + .long sl_gdt - sl_gdt_desc
> +SYM_DATA_END_LABEL(sl_gdt_desc, SYM_L_LOCAL, sl_gdt_desc_end)
> +
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_gdt)
> + .quad 0x0000000000000000 /* NULL */
> + .quad 0x00cf9a000000ffff /* __SL32_CS */
> + .quad 0x00cf92000000ffff /* __SL32_DS */
> +SYM_DATA_END_LABEL(sl_gdt, SYM_L_LOCAL, sl_gdt_end)
> +
> + .balign 8
> +SYM_DATA_START_LOCAL(sl_smx_rlp_mle_join)
> + .long sl_gdt_end - sl_gdt - 1 /* GDT limit */
> + .long 0x00000000 /* GDT base */
> + .long __SL32_CS /* Seg Sel - CS (DS, ES, SS = seg_sel+8) */
> + .long 0x00000000 /* Entry point physical address */
> +SYM_DATA_END(sl_smx_rlp_mle_join)
> +
> +SYM_DATA(sl_cpu_type, .long 0x00000000)
> +
> +SYM_DATA(sl_mle_start, .long 0x00000000)
> +
> +SYM_DATA_LOCAL(sl_txt_spin_lock, .long 0x00000000)
> +
> +SYM_DATA_LOCAL(sl_txt_stack_index, .long 0x00000000)
> +
> +SYM_DATA_LOCAL(sl_txt_cpu_count, .long 0x00000000)
> +
> +SYM_DATA_LOCAL(sl_txt_ap_wake_block, .long 0x00000000)
> diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
> index e022e6eb766c..37f6167f28ba 100644
> --- a/arch/x86/include/asm/msr-index.h
> +++ b/arch/x86/include/asm/msr-index.h
> @@ -348,6 +348,9 @@
> #define MSR_IA32_RTIT_OUTPUT_BASE 0x00000560
> #define MSR_IA32_RTIT_OUTPUT_MASK 0x00000561
>
> +#define MSR_MTRRphysBase0 0x00000200
> +#define MSR_MTRRphysMask0 0x00000201
> +
> #define MSR_MTRRfix64K_00000 0x00000250
> #define MSR_MTRRfix16K_80000 0x00000258
> #define MSR_MTRRfix16K_A0000 0x00000259
> @@ -849,6 +852,8 @@
> #define MSR_IA32_APICBASE_ENABLE (1<<11)
> #define MSR_IA32_APICBASE_BASE (0xfffff<<12)
>
> +#define MSR_IA32_X2APIC_APICID 0x00000802
> +
> #define MSR_IA32_UCODE_WRITE 0x00000079
> #define MSR_IA32_UCODE_REV 0x0000008b
>
> diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
> index 9b82eebd7add..7ce283a22d6b 100644
> --- a/arch/x86/include/uapi/asm/bootparam.h
> +++ b/arch/x86/include/uapi/asm/bootparam.h
> @@ -12,6 +12,7 @@
> /* loadflags */
> #define LOADED_HIGH (1<<0)
> #define KASLR_FLAG (1<<1)
> +#define SLAUNCH_FLAG (1<<2)
> #define QUIET_FLAG (1<<5)
> #define KEEP_SEGMENTS (1<<6)
> #define CAN_USE_HEAP (1<<7)
> diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
> index a98020bf31bb..925adce6e2c7 100644
> --- a/arch/x86/kernel/asm-offsets.c
> +++ b/arch/x86/kernel/asm-offsets.c
> @@ -13,6 +13,8 @@
> #include <linux/hardirq.h>
> #include <linux/suspend.h>
> #include <linux/kbuild.h>
> +#include <linux/slr_table.h>
> +#include <linux/slaunch.h>
> #include <asm/processor.h>
> #include <asm/thread_info.h>
> #include <asm/sigframe.h>
> @@ -120,4 +122,22 @@ static void __used common(void)
> OFFSET(ARIA_CTX_rounds, aria_ctx, rounds);
> #endif
>
> +#ifdef CONFIG_SECURE_LAUNCH
> + BLANK();
> + OFFSET(SL_txt_info, txt_os_mle_data, txt_info);
> + OFFSET(SL_mle_scratch, txt_os_mle_data, mle_scratch);
> + OFFSET(SL_boot_params_addr, txt_os_mle_data, boot_params_addr);
> + OFFSET(SL_ap_wake_block, txt_os_mle_data, ap_wake_block);
> + OFFSET(SL_ap_wake_block_size, txt_os_mle_data, ap_wake_block_size);
> + OFFSET(SL_saved_misc_enable_msr, slr_entry_intel_info, saved_misc_enable_msr);
> + OFFSET(SL_saved_bsp_mtrrs, slr_entry_intel_info, saved_bsp_mtrrs);
> + OFFSET(SL_num_logical_procs, txt_bios_data, num_logical_procs);
> + OFFSET(SL_capabilities, txt_os_sinit_data, capabilities);
> + OFFSET(SL_mle_size, txt_os_sinit_data, mle_size);
> + OFFSET(SL_vtd_pmr_lo_base, txt_os_sinit_data, vtd_pmr_lo_base);
> + OFFSET(SL_vtd_pmr_lo_size, txt_os_sinit_data, vtd_pmr_lo_size);
> + OFFSET(SL_rlp_wakeup_addr, txt_sinit_mle_data, rlp_wakeup_addr);
> + OFFSET(SL_rlp_gdt_base, smx_rlp_mle_join, rlp_gdt_base);
> + OFFSET(SL_rlp_entry_point, smx_rlp_mle_join, rlp_entry_point);
> +#endif
> }
> --
> 2.39.3
>

2024-05-31 14:04:35

by Ard Biesheuvel

Subject: Re: [PATCH v9 08/19] x86: Secure Launch kernel early boot stub

On Fri, 31 May 2024 at 15:33, Ard Biesheuvel <[email protected]> wrote:
>
> On Fri, 31 May 2024 at 13:00, Ard Biesheuvel <[email protected]> wrote:
> >
> > Hello Ross,
> >
> > On Fri, 31 May 2024 at 03:32, Ross Philipson <[email protected]> wrote:
> > >
> > > The Secure Launch (SL) stub provides the entry point for Intel TXT (and
> > > later AMD SKINIT) to vector to during the late launch. The symbol
> > > sl_stub_entry is that entry point and its offset into the kernel is
> > > conveyed to the launching code using the MLE (Measured Launch
> > > Environment) header in the structure named mle_header. The offset of the
> > > MLE header is set in the kernel_info. The routine sl_stub contains the
> > > very early late launch setup code responsible for setting up the basic
> > > environment to allow the normal kernel startup_32 code to proceed. It is
> > > also responsible for properly waking and handling the APs on Intel
> > > platforms. The routine sl_main which runs after entering 64b mode is
> > > responsible for measuring configuration and module information before
> > > it is used like the boot params, the kernel command line, the TXT heap,
> > > an external initramfs, etc.
> > >
> > > Signed-off-by: Ross Philipson <[email protected]>
> > > ---
> > > Documentation/arch/x86/boot.rst | 21 +
> > > arch/x86/boot/compressed/Makefile | 3 +-
> > > arch/x86/boot/compressed/head_64.S | 30 +
> > > arch/x86/boot/compressed/kernel_info.S | 34 ++
> > > arch/x86/boot/compressed/sl_main.c | 577 ++++++++++++++++++++
> > > arch/x86/boot/compressed/sl_stub.S | 725 +++++++++++++++++++++++++
> > > arch/x86/include/asm/msr-index.h | 5 +
> > > arch/x86/include/uapi/asm/bootparam.h | 1 +
> > > arch/x86/kernel/asm-offsets.c | 20 +
> > > 9 files changed, 1415 insertions(+), 1 deletion(-)
> > > create mode 100644 arch/x86/boot/compressed/sl_main.c
> > > create mode 100644 arch/x86/boot/compressed/sl_stub.S
> > >
> > > diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst
> > > index 4fd492cb4970..295cdf9bcbdb 100644
> > > --- a/Documentation/arch/x86/boot.rst
> > > +++ b/Documentation/arch/x86/boot.rst
> > > @@ -482,6 +482,14 @@ Protocol: 2.00+
> > > - If 1, KASLR enabled.
> > > - If 0, KASLR disabled.
> > >
> > > + Bit 2 (kernel internal): SLAUNCH_FLAG
> > > +
> > > + - Used internally by the setup kernel to communicate
> > > + Secure Launch status to kernel proper.
> > > +
> > > + - If 1, Secure Launch enabled.
> > > + - If 0, Secure Launch disabled.
> > > +
> > > Bit 5 (write): QUIET_FLAG
> > >
> > > - If 0, print early messages.
> > > @@ -1028,6 +1036,19 @@ Offset/size: 0x000c/4
> > >
> > > This field contains maximal allowed type for setup_data and setup_indirect structs.
> > >
> > > +============ =================
> > > +Field name: mle_header_offset
> > > +Offset/size: 0x0010/4
> > > +============ =================
> > > +
> > > + This field contains the offset to the Secure Launch Measured Launch Environment
> > > + (MLE) header. This offset is used to locate information needed during a secure
> > > + late launch using Intel TXT. If the offset is zero, the kernel does not have
> > > + Secure Launch capabilities. The MLE entry point is called from TXT on the BSP
> > > + following a success measured launch. The specific state of the processors is
> > > + outlined in the TXT Software Development Guide, the latest can be found here:
> > > + https://www.intel.com/content/dam/www/public/us/en/documents/guides/intel-txt-software-development-guide.pdf
> > > +
> > >
> >
> > Could we just repaint this field as the offset relative to the start
> > of kernel_info rather than relative to the start of the image? That
> > way, there is no need for patch #1, and given that the consumer of
> > this field accesses it via kernel_info, I wouldn't expect any issues
> > in applying this offset to obtain the actual address.
> >
> >
> > > The Image Checksum
> > > ==================
> > > diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
> > > index 9189a0e28686..9076a248d4b4 100644
> > > --- a/arch/x86/boot/compressed/Makefile
> > > +++ b/arch/x86/boot/compressed/Makefile
> > > @@ -118,7 +118,8 @@ vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
> > > vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_mixed.o
> > > vmlinux-objs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
> > >
> > > -vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o
> > > +vmlinux-objs-$(CONFIG_SECURE_LAUNCH) += $(obj)/early_sha1.o $(obj)/early_sha256.o \
> > > + $(obj)/sl_main.o $(obj)/sl_stub.o
> > >
> > > $(obj)/vmlinux: $(vmlinux-objs-y) FORCE
> > > $(call if_changed,ld)
> > > diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
> > > index 1dcb794c5479..803c9e2e6d85 100644
> > > --- a/arch/x86/boot/compressed/head_64.S
> > > +++ b/arch/x86/boot/compressed/head_64.S
> > > @@ -420,6 +420,13 @@ SYM_CODE_START(startup_64)
> > > pushq $0
> > > popfq
> > >
> > > +#ifdef CONFIG_SECURE_LAUNCH
> > > + /* Ensure the relocation region is coverd by a PMR */
> >
> > covered
> >
> > > + movq %rbx, %rdi
> > > + movl $(_bss - startup_32), %esi
> > > + callq sl_check_region
> > > +#endif
> > > +
> > > /*
> > > * Copy the compressed kernel to the end of our buffer
> > > * where decompression in place becomes safe.
> > > @@ -462,6 +469,29 @@ SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated)
> > > shrq $3, %rcx
> > > rep stosq
> > >
> > > +#ifdef CONFIG_SECURE_LAUNCH
> > > + /*
> > > + * Have to do the final early sl stub work in 64b area.
> > > + *
> > > + * *********** NOTE ***********
> > > + *
> > > + * Several boot params get used before we get a chance to measure
> > > + * them in this call. This is a known issue and we currently don't
> > > + * have a solution. The scratch field doesn't matter. There is no
> > > + * obvious way to do anything about the use of kernel_alignment or
> > > + * init_size though these seem low risk with all the PMR and overlap
> > > + * checks in place.
> > > + */
> > > + movq %r15, %rdi
> > > + callq sl_main
> > > +
> > > + /* Ensure the decompression location is covered by a PMR */
> > > + movq %rbp, %rdi
> > > + movq output_len(%rip), %rsi
> > > + callq sl_check_region
> > > +#endif
> > > +
> > > + pushq %rsi
> >
> > This looks like a rebase error.
> >
> > > call load_stage2_idt
> > >
> > > /* Pass boot_params to initialize_identity_maps() */
> > > diff --git a/arch/x86/boot/compressed/kernel_info.S b/arch/x86/boot/compressed/kernel_info.S
> > > index c18f07181dd5..e199b87764e9 100644
> > > --- a/arch/x86/boot/compressed/kernel_info.S
> > > +++ b/arch/x86/boot/compressed/kernel_info.S
> > > @@ -28,6 +28,40 @@ SYM_DATA_START(kernel_info)
> > > /* Maximal allowed type for setup_data and setup_indirect structs. */
> > > .long SETUP_TYPE_MAX
> > >
> > > + /* Offset to the MLE header structure */
> > > +#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
> > > + .long rva(mle_header)
> >
> > ... so this could just be mle_header - kernel_info, and the consumer
> > can do the math instead.
> >
> > > +#else
> > > + .long 0
> > > +#endif
> > > +
> > > kernel_info_var_len_data:
> > > /* Empty for time being... */
> > > SYM_DATA_END_LABEL(kernel_info, SYM_L_LOCAL, kernel_info_end)
> > > +
> > > +#if IS_ENABLED(CONFIG_SECURE_LAUNCH)
> > > + /*
> > > + * The MLE Header per the TXT Specification, section 2.1
> > > + * MLE capabilities, see table 4. Capabilities set:
> > > + * bit 0: Support for GETSEC[WAKEUP] for RLP wakeup
> > > + * bit 1: Support for RLP wakeup using MONITOR address
> > > + * bit 2: The ECX register will contain the pointer to the MLE page table
> > > + * bit 5: TPM 1.2 family: Details/authorities PCR usage support
> > > + * bit 9: Supported format of TPM 2.0 event log - TCG compliant
> > > + */
> > > +SYM_DATA_START(mle_header)
> > > + .long 0x9082ac5a /* UUID0 */
> > > + .long 0x74a7476f /* UUID1 */
> > > + .long 0xa2555c0f /* UUID2 */
> > > + .long 0x42b651cb /* UUID3 */
> > > + .long 0x00000034 /* MLE header size */
> > > + .long 0x00020002 /* MLE version 2.2 */
> > > + .long rva(sl_stub_entry) /* Linear entry point of MLE (virt. address) */
> >
> > and these should perhaps be relative to mle_header?
> >
> > > + .long 0x00000000 /* First valid page of MLE */
> > > + .long 0x00000000 /* Offset within binary of first byte of MLE */
> > > + .long rva(_edata) /* Offset within binary of last byte + 1 of MLE */
> >
> > and here
> >
>
> Ugh never mind - these are specified externally.

OK, so instead of patch #1, please use the linker script to generate
these constants.

I.e., add this to arch/x86/boot/compressed/vmlinux.lds.S

#ifdef CONFIG_SECURE_LAUNCH
PROVIDE(mle_header_offset = mle_header - startup_32);
PROVIDE(sl_stub_entry_offset = sl_stub_entry - startup_32);
PROVIDE(_edata_offset = _edata - startup_32);
#endif

and use the symbols on the left hand side in the code.