[PATCH v2 1/2] kexec, KEYS: make the code in bzImage64_verify_sig generic

[Coiby Xu <coxu@redhat.com>]

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 <coxu@redhat.com>
---
 arch/x86/kernel/kexec-bzimage64.c | 13 +------------
 include/linux/kexec.h             |  3 +++
 kernel/kexec_file.c               | 17 +++++++++++++++++
 3 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index 170d0fd68b1f..4136dd3be5a9 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 arch_kexec_kernel_verify_pe_sig(kernel, kernel_len);
 }
 #endif
 
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 0c994ae37729..d45f32336dbe 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>
@@ -199,6 +200,8 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image);
 #ifdef CONFIG_KEXEC_SIG
 int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 				 unsigned long buf_len);
+int arch_kexec_kernel_verify_pe_sig(const char *kernel,
+				    unsigned long kernel_len);
 #endif
 int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
 
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 33400ff051a8..0530275b7aa3 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -106,6 +106,23 @@ int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 {
 	return kexec_image_verify_sig_default(image, buf, buf_len);
 }
+
+#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
+int arch_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
 #endif
 
 /*
-- 
2.31.1