From: Ashok Raj <[email protected]>
One of the existing reserved fields in microcode header has been
allocated to indicate the size for metadata structures.
The location of metadata section within microcode header is as shown
below:
Microcode Format
+----------------------+ Base
|Header Version |
+----------------------+
|Update revision |
+----------------------+
|Date DDMMYYYY |
+----------------------+
|Sig |
+----------------------+
|Checksum |
+----------------------+
|Loader Version |
+----------------------+
|Processor Flags |
+----------------------+
|Data Size |
+----------------------+
|Total Size |
+----------------------+
|Meta Size |
+----------------------+
|Reserved |
+----------------------+
|Reserved |
+----------------------+ Base+48
| |
| |
| |
| |
| Microcode |
| |
| Data |
| |
| |
+----------------------+ Base+48+data_size-
| | meta_size
| Meta Data |
| structure(s) |
| |
+----------------------+ Base+48+data_size
| Extended Signature |
| Table |
| |
| |
| |
| |
| |
+----------------------+ Base+total_size
Add an accessor function which will return a pointer to the
start of a specific meta_type being queried.
Upcoming changes will introduce the layout of IFS metadata
structure and will make use of metadata section.
Reviewed-by: Tony Luck <[email protected]>
Reviewed-by: Sohil Mehta <[email protected]>
Reviewed-by: Hans de Goede <[email protected]>
Signed-off-by: Ashok Raj <[email protected]>
Signed-off-by: Jithu Joseph <[email protected]>
---
drivers/platform/x86/intel/ifs/load.c | 32 +++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/drivers/platform/x86/intel/ifs/load.c b/drivers/platform/x86/intel/ifs/load.c
index c914e4d359db..713f18ce00a1 100644
--- a/drivers/platform/x86/intel/ifs/load.c
+++ b/drivers/platform/x86/intel/ifs/load.c
@@ -43,6 +43,38 @@ static const char * const scan_authentication_status[] = {
[2] = "Chunk authentication error. The hash of chunk did not match expected value"
};
+#define MC_HEADER_META_TYPE_END (0)
+
+struct metadata_header {
+ unsigned int type;
+ unsigned int blk_size;
+};
+
+static struct metadata_header *find_meta_data(void *ucode, unsigned int meta_type)
+{
+ struct metadata_header *meta_header;
+ unsigned long data_size, total_meta;
+ unsigned long meta_size = 0;
+
+ data_size = get_datasize(ucode);
+ total_meta = ((struct microcode_intel *)ucode)->hdr.metasize;
+ if (!total_meta)
+ return NULL;
+
+ meta_header = (ucode + MC_HEADER_SIZE + data_size) - total_meta;
+
+ while (meta_header->type != MC_HEADER_META_TYPE_END &&
+ meta_header->blk_size &&
+ meta_size < total_meta) {
+ meta_size += meta_header->blk_size;
+ if (meta_header->type == meta_type)
+ return meta_header;
+
+ meta_header = (void *)meta_header + meta_header->blk_size;
+ }
+ return NULL;
+}
+
/*
* To copy scan hashes and authenticate test chunks, the initiating cpu must point
* to the EDX:EAX to the test image in linear address.
--
2.25.1
The following commit has been merged into the x86/microcode branch of tip:
Commit-ID: 8382fee3bb86526bde1bfb1a06834f056140e0dd
Gitweb: https://git.kernel.org/tip/8382fee3bb86526bde1bfb1a06834f056140e0dd
Author: Ashok Raj <[email protected]>
AuthorDate: Wed, 16 Nov 2022 19:59:29 -08:00
Committer: Borislav Petkov <[email protected]>
CommitterDate: Sat, 19 Nov 2022 10:39:08 +01:00
platform/x86/intel/ifs: Add metadata support
One of the existing reserved fields in the microcode header has been
allocated to indicate the size of metadata structures.
The location of metadata section within microcode header is as shown
below:
Microcode Blob Format
+----------------------+ Base
|Header Version |
+----------------------+
|Update revision |
+----------------------+
|Date DDMMYYYY |
+----------------------+
|Sig |
+----------------------+
|Checksum |
+----------------------+
|Loader Version |
+----------------------+
|Processor Flags |
+----------------------+
|Data Size |
+----------------------+
|Total Size |
+----------------------+
|Meta Size |
+----------------------+
|Reserved |
+----------------------+
|Reserved |
+----------------------+ Base+48
| |
| Microcode |
| Data |
| |
+----------------------+ Base+48+data_size-
| | meta_size
| Meta Data |
| structure(s) |
| |
+----------------------+ Base+48+data_size
| |
| Extended Signature |
| Table |
| |
+----------------------+ Base+total_size
Add an accessor function which will return a pointer to the start of a
specific meta_type being queried.
[ bp: Massage commit message. ]
Signed-off-by: Ashok Raj <[email protected]>
Signed-off-by: Jithu Joseph <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Reviewed-by: Tony Luck <[email protected]>
Reviewed-by: Sohil Mehta <[email protected]>
Reviewed-by: Hans de Goede <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
drivers/platform/x86/intel/ifs/load.c | 32 ++++++++++++++++++++++++++-
1 file changed, 32 insertions(+)
diff --git a/drivers/platform/x86/intel/ifs/load.c b/drivers/platform/x86/intel/ifs/load.c
index 8423c48..9228da5 100644
--- a/drivers/platform/x86/intel/ifs/load.c
+++ b/drivers/platform/x86/intel/ifs/load.c
@@ -43,6 +43,38 @@ static const char * const scan_authentication_status[] = {
[2] = "Chunk authentication error. The hash of chunk did not match expected value"
};
+#define MC_HEADER_META_TYPE_END (0)
+
+struct metadata_header {
+ unsigned int type;
+ unsigned int blk_size;
+};
+
+static struct metadata_header *find_meta_data(void *ucode, unsigned int meta_type)
+{
+ struct metadata_header *meta_header;
+ unsigned long data_size, total_meta;
+ unsigned long meta_size = 0;
+
+ data_size = get_datasize(ucode);
+ total_meta = ((struct microcode_intel *)ucode)->hdr.metasize;
+ if (!total_meta)
+ return NULL;
+
+ meta_header = (ucode + MC_HEADER_SIZE + data_size) - total_meta;
+
+ while (meta_header->type != MC_HEADER_META_TYPE_END &&
+ meta_header->blk_size &&
+ meta_size < total_meta) {
+ meta_size += meta_header->blk_size;
+ if (meta_header->type == meta_type)
+ return meta_header;
+
+ meta_header = (void *)meta_header + meta_header->blk_size;
+ }
+ return NULL;
+}
+
/*
* To copy scan hashes and authenticate test chunks, the initiating cpu must point
* to the EDX:EAX to the test image in linear address.