2022-03-18 14:46:58

by Coiby Xu

[permalink] [raw]
Subject: [PATCH v4 2/3] kexec, KEYS: make the code in bzImage64_verify_sig generic

The code in bzImage64_verify_sig could make use of system keyrings
including .buitin_trusted_keys, .secondary_trusted_keys and .platform
keyring to verify signed kernel image as PE file. Make it generic so
both x86_64 and arm64 can use it.

Signed-off-by: Coiby Xu <[email protected]>
---
arch/x86/kernel/kexec-bzimage64.c | 13 +------------
include/linux/kexec.h | 7 +++++++
kernel/kexec_file.c | 17 +++++++++++++++++
3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index 170d0fd68b1f..f73aab3fde33 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -17,7 +17,6 @@
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/efi.h>
-#include <linux/verification.h>

#include <asm/bootparam.h>
#include <asm/setup.h>
@@ -531,17 +530,7 @@ static int bzImage64_cleanup(void *loader_data)
#ifdef CONFIG_KEXEC_BZIMAGE_VERIFY_SIG
static int bzImage64_verify_sig(const char *kernel, unsigned long kernel_len)
{
- int ret;
-
- ret = verify_pefile_signature(kernel, kernel_len,
- VERIFY_USE_SECONDARY_KEYRING,
- VERIFYING_KEXEC_PE_SIGNATURE);
- if (ret == -ENOKEY && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING)) {
- ret = verify_pefile_signature(kernel, kernel_len,
- VERIFY_USE_PLATFORM_KEYRING,
- VERIFYING_KEXEC_PE_SIGNATURE);
- }
- return ret;
+ return kexec_kernel_verify_pe_sig(kernel, kernel_len);
}
#endif

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 755fed183224..2fe39e946988 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -19,6 +19,7 @@
#include <asm/io.h>

#include <uapi/linux/kexec.h>
+#include <linux/verification.h>

#ifdef CONFIG_KEXEC_CORE
#include <linux/list.h>
@@ -196,6 +197,12 @@ int arch_kexec_apply_relocations(struct purgatory_info *pi,
const Elf_Shdr *relsec,
const Elf_Shdr *symtab);
int arch_kimage_file_post_load_cleanup(struct kimage *image);
+#ifdef CONFIG_KEXEC_SIG
+#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
+int kexec_kernel_verify_pe_sig(const char *kernel,
+ unsigned long kernel_len);
+#endif
+#endif
int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);

extern int kexec_add_buffer(struct kexec_buf *kbuf);
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 3720435807eb..754885b96aab 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -165,6 +165,23 @@ void kimage_file_post_load_cleanup(struct kimage *image)
}

#ifdef CONFIG_KEXEC_SIG
+#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
+int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len)
+{
+ int ret;
+
+ ret = verify_pefile_signature(kernel, kernel_len,
+ VERIFY_USE_SECONDARY_KEYRING,
+ VERIFYING_KEXEC_PE_SIGNATURE);
+ if (ret == -ENOKEY && IS_ENABLED(CONFIG_INTEGRITY_PLATFORM_KEYRING)) {
+ ret = verify_pefile_signature(kernel, kernel_len,
+ VERIFY_USE_PLATFORM_KEYRING,
+ VERIFYING_KEXEC_PE_SIGNATURE);
+ }
+ return ret;
+}
+#endif
+
static int kexec_image_verify_sig(struct kimage *image, void *buf,
unsigned long buf_len)
{
--
2.34.1