Move x509_check_for_self_signed as a common helper function
that can be shared by legacy crypto lib and MbedTLS implementation.
Signed-off-by: Raymond Mao <raymond....@linaro.org>
---
Changes in v4
- Initial patch.
lib/crypto/Makefile | 1 +
lib/crypto/x509_helper.c | 67 ++++++++++++++++++++++++++++++++++++
lib/crypto/x509_public_key.c | 56 +-----------------------------
3 files changed, 69 insertions(+), 55 deletions(-)
create mode 100644 lib/crypto/x509_helper.c
diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile
index 4ad1849040d..946cc3a7b59 100644
--- a/lib/crypto/Makefile
+++ b/lib/crypto/Makefile
@@ -37,6 +37,7 @@ x509_key_parser-y := \
x509.asn1.o \
x509_akid.asn1.o \
x509_cert_parser.o \
+ x509_helper.o \
x509_public_key.o
$(obj)/x509_cert_parser.o: \
diff --git a/lib/crypto/x509_helper.c b/lib/crypto/x509_helper.c
new file mode 100644
index 00000000000..d0c80907ec3
--- /dev/null
+++ b/lib/crypto/x509_helper.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * X509 helper functions
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowe...@redhat.com)
+ *
+ * Copyright (c) 2024 Linaro Limited
+ * Author: Raymond Mao <raymond....@linaro.org>
+ */
+#include <linux/err.h>
+#include <crypto/public_key.h>
+#include <crypto/x509_parser.h>
+
+/*
+ * Check for self-signedness in an X.509 cert and if found, check the signature
+ * immediately if we can.
+ */
+int x509_check_for_self_signed(struct x509_certificate *cert)
+{
+ int ret = 0;
+
+ if (cert->raw_subject_size != cert->raw_issuer_size ||
+ memcmp(cert->raw_subject, cert->raw_issuer,
+ cert->raw_issuer_size))
+ goto not_self_signed;
+
+ if (cert->sig->auth_ids[0] || cert->sig->auth_ids[1]) {
+ /*
+ * If the AKID is present it may have one or two parts. If
+ * both are supplied, both must match.
+ */
+ bool a = asymmetric_key_id_same(cert->skid,
+ cert->sig->auth_ids[1]);
+ bool b = asymmetric_key_id_same(cert->id,
+ cert->sig->auth_ids[0]);
+
+ if (!a && !b)
+ goto not_self_signed;
+
+ ret = -EKEYREJECTED;
+ if (((a && !b) || (b && !a)) &&
+ cert->sig->auth_ids[0] && cert->sig->auth_ids[1])
+ goto out;
+ }
+
+ ret = -EKEYREJECTED;
+ if (strcmp(cert->pub->pkey_algo, cert->sig->pkey_algo))
+ goto out;
+
+ ret = public_key_verify_signature(cert->pub, cert->sig);
+ if (ret == -ENOPKG) {
+ cert->unsupported_sig = true;
+ goto not_self_signed;
+ }
+ if (ret < 0)
+ goto out;
+
+ pr_devel("Cert Self-signature verified");
+ cert->self_signed = true;
+
+out:
+ return ret;
+
+not_self_signed:
+ return 0;
+}
diff --git a/lib/crypto/x509_public_key.c b/lib/crypto/x509_public_key.c
index a10145a7cdc..4ba13c1adc3 100644
--- a/lib/crypto/x509_public_key.c
+++ b/lib/crypto/x509_public_key.c
@@ -139,61 +139,7 @@ error:
return ret;
}
-/*
- * Check for self-signedness in an X.509 cert and if found, check the signature
- * immediately if we can.
- */
-int x509_check_for_self_signed(struct x509_certificate *cert)
-{
- int ret = 0;
-
- pr_devel("==>%s()\n", __func__);
-
- if (cert->raw_subject_size != cert->raw_issuer_size ||
- memcmp(cert->raw_subject, cert->raw_issuer,
- cert->raw_issuer_size) != 0)
- goto not_self_signed;
-
- if (cert->sig->auth_ids[0] || cert->sig->auth_ids[1]) {
- /* If the AKID is present it may have one or two parts. If
- * both are supplied, both must match.
- */
- bool a = asymmetric_key_id_same(cert->skid,
cert->sig->auth_ids[1]);
- bool b = asymmetric_key_id_same(cert->id,
cert->sig->auth_ids[0]);
-
- if (!a && !b)
- goto not_self_signed;
-
- ret = -EKEYREJECTED;
- if (((a && !b) || (b && !a)) &&
- cert->sig->auth_ids[0] && cert->sig->auth_ids[1])
- goto out;
- }
-
- ret = -EKEYREJECTED;
- if (strcmp(cert->pub->pkey_algo, cert->sig->pkey_algo) != 0)
- goto out;
-
- ret = public_key_verify_signature(cert->pub, cert->sig);
- if (ret < 0) {
- if (ret == -ENOPKG) {
- cert->unsupported_sig = true;
- ret = 0;
- }
- goto out;
- }
-
- pr_devel("Cert Self-signature verified");
- cert->self_signed = true;
-
-out:
- pr_devel("<==%s() = %d\n", __func__, ret);
- return ret;
-
-not_self_signed:
- pr_devel("<==%s() = 0 [not]\n", __func__);
- return 0;
-}
+#endif /* !CONFIG_IS_ENABLED(MBEDTLS_LIB_X509) */
#ifndef __UBOOT__
/*
--
2.25.1
