@@ -11,6 +11,12 @@
#include <linux/oid_registry.h>
#include <crypto/pkcs7.h>
#include <crypto/x509_parser.h>
+#if CONFIG_IS_ENABLED(MBEDTLS_LIB_X509)
+#include <external/mbedtls/include/mbedtls/pkcs7.h>
+#include <external/mbedtls/library/x509_internal.h>
+#include <external/mbedtls/include/mbedtls/asn1.h>
+#include <external/mbedtls/include/mbedtls/oid.h>
+#endif
#include <linux/printk.h>
#define kenter(FMT, ...) \
@@ -18,7 +24,54 @@
#define kleave(FMT, ...) \
pr_devel("<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+/* Backup the parsed MedTLS context that we need */
+#if CONFIG_IS_ENABLED(MBEDTLS_LIB_X509)
+struct pkcs7_mbedtls_ctx {
+ void *content_data;
+};
+
+struct pkcs7_sinfo_mbedtls_ctx {
+ void *authattrs_data;
+ void *content_data_digest;
+};
+#endif
+
+/*
+ * MbedTLS integration Notes:
+ *
+ * MbedTLS PKCS#7 library does not originally support parsing MicroSoft
+ * Authentication Code which is used for verifying the PE image digest.
+ *
+ * 1. Authenticated Attributes (authenticatedAttributes)
+ * MbedTLS assumes unauthenticatedAttributes and authenticatedAttributes
+ * fields not exist.
+ * See MbedTLS function 'pkcs7_get_signer_info' for details.
+ *
+ * 2. MicroSoft Authentication Code (mscode)
+ * MbedTLS only supports Content Data type defined as 1.2.840.113549.1.7.1
+ * (MBEDTLS_OID_PKCS7_DATA, aka OID_data).
+ * 1.3.6.1.4.1.311.2.1.4 (MicroSoft Authentication Code, aka
+ * OID_msIndirectData) is not supported.
+ * See MbedTLS function 'pkcs7_get_content_info_type' for details.
+ *
+ * But the EFI loader assumes that a PKCS#7 message with an EFI image always
+ * contains MicroSoft Authentication Code as Content Data (msg->data is NOT
+ * NULL), see function 'efi_signature_verify'.
+ *
+ * MbedTLS patch "0002-support-MicroSoft-authentication-code-in-PKCS7-lib.patch"
+ * is to support both above features by parsing the Content Data and
+ * Authenticate Attributes from a given PKCS#7 message.
+ *
+ * Other fields we don't need to populate from MbedTLS, which are used
+ * internally by pkcs7_verify:
+ * 'signer', 'unsupported_crypto', 'blacklisted'
+ * 'sig->digest' is used internally by pkcs7_digest to calculate the hash of
+ * Content Data or Authenticate Attributes.
+ */
struct pkcs7_signed_info {
+#if CONFIG_IS_ENABLED(MBEDTLS_LIB_X509)
+ struct pkcs7_sinfo_mbedtls_ctx *mbedtls_ctx;
+#endif
struct pkcs7_signed_info *next;
struct x509_certificate *signer; /* Signing certificate (in msg->certs) */
unsigned index;
@@ -55,6 +108,9 @@ struct pkcs7_signed_info {
};
struct pkcs7_message {
+#if CONFIG_IS_ENABLED(MBEDTLS_LIB_X509)
+ struct pkcs7_mbedtls_ctx *mbedtls_ctx;
+#endif
struct x509_certificate *certs; /* Certificate list */
struct x509_certificate *crl; /* Revocation list */
struct pkcs7_signed_info *signed_infos;
@@ -48,6 +48,7 @@ $(obj)/x509.asn1.o: $(obj)/x509.asn1.c $(obj)/x509.asn1.h
$(obj)/x509_akid.asn1.o: $(obj)/x509_akid.asn1.c $(obj)/x509_akid.asn1.h
endif
+ifneq ($(CONFIG_MBEDTLS_LIB_X509), y)
#
# PKCS#7 message handling
#
@@ -55,10 +56,11 @@ obj-$(CONFIG_$(SPL_)PKCS7_MESSAGE_PARSER) += pkcs7_message.o
pkcs7_message-y := \
pkcs7.asn1.o \
pkcs7_parser.o
-obj-$(CONFIG_$(SPL_)PKCS7_VERIFY) += pkcs7_verify.o
$(obj)/pkcs7_parser.o: $(obj)/pkcs7.asn1.h
$(obj)/pkcs7.asn1.o: $(obj)/pkcs7.asn1.c $(obj)/pkcs7.asn1.h
+endif
+obj-$(CONFIG_$(SPL_)PKCS7_VERIFY) += pkcs7_verify.o
#
# Signed PE binary-wrapped key handling
Adapt PKCS7 parser to build with MbedTLS Signed-off-by: Raymond Mao <raymond.mao@linaro.org> --- Changes in v2 - Move the porting layer to MbedTLS dir. include/crypto/pkcs7_parser.h | 56 +++++++++++++++++++++++++++++++++++ lib/crypto/Makefile | 4 ++- 2 files changed, 59 insertions(+), 1 deletion(-)