diff mbox series

[v7,3/4] x509: Add support for parsing x509 certs with ECDSA keys

Message ID 20210201151910.1465705-4-stefanb@linux.ibm.com
State New
Headers show
Series Add support for x509 certs with NIST p256 and p192 keys | expand

Commit Message

Stefan Berger Feb. 1, 2021, 3:19 p.m. UTC
This patch adds support for parsing of x509 certificates that contain
ECDSA keys, such as NIST P256, that have been signed by a CA using any
of the current SHA hash algorithms.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: keyrings@vger.kernel.org
---
 crypto/asymmetric_keys/public_key.c       | 19 ++++++++++++++
 crypto/asymmetric_keys/x509_cert_parser.c | 32 ++++++++++++++++++++++-
 include/linux/oid_registry.h              |  2 ++
 3 files changed, 52 insertions(+), 1 deletion(-)

Comments

kernel test robot Feb. 11, 2021, 8:03 a.m. UTC | #1
Hi Stefan,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on cryptodev/master]
[also build test ERROR on crypto/master security/next-testing v5.11-rc7 next-20210125]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Stefan-Berger/Add-support-for-x509-certs-with-NIST-p256-and-p192-keys/20210201-232803
base:   https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master
config: x86_64-randconfig-a011-20200911 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/6e1523b0e77785c263bcb639b87a862ae59731a4
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Stefan-Berger/Add-support-for-x509-certs-with-NIST-p256-and-p192-keys/20210201-232803
        git checkout 6e1523b0e77785c263bcb639b87a862ae59731a4
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   ld: crypto/asymmetric_keys/public_key.o: in function `software_key_determine_akcipher':
>> crypto/asymmetric_keys/public_key.c:97: undefined reference to `parse_OID'



vim +97 crypto/asymmetric_keys/public_key.c

    61	
    62	/*
    63	 * Determine the crypto algorithm name.
    64	 */
    65	static
    66	int software_key_determine_akcipher(const char *encoding,
    67					    const char *hash_algo,
    68					    const struct public_key *pkey,
    69					    char alg_name[CRYPTO_MAX_ALG_NAME])
    70	{
    71		int n;
    72	
    73		if (strcmp(encoding, "pkcs1") == 0) {
    74			/* The data wangled by the RSA algorithm is typically padded
    75			 * and encoded in some manner, such as EMSA-PKCS1-1_5 [RFC3447
    76			 * sec 8.2].
    77			 */
    78			if (!hash_algo)
    79				n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
    80					     "pkcs1pad(%s)",
    81					     pkey->pkey_algo);
    82			else
    83				n = snprintf(alg_name, CRYPTO_MAX_ALG_NAME,
    84					     "pkcs1pad(%s,%s)",
    85					     pkey->pkey_algo, hash_algo);
    86			return n >= CRYPTO_MAX_ALG_NAME ? -EINVAL : 0;
    87		}
    88	
    89		if (strcmp(encoding, "raw") == 0) {
    90			strcpy(alg_name, pkey->pkey_algo);
    91			return 0;
    92		}
    93	
    94		if (strcmp(encoding, "x962") == 0) {
    95			enum OID oid;
    96	
  > 97			if (parse_OID(pkey->params, pkey->paramlen, &oid) != 0)

    98				return -EBADMSG;
    99	
   100			switch (oid) {
   101			case OID_id_prime192v1:
   102				strcpy(alg_name, "ecdsa-nist-p192");
   103				return 0;
   104			case OID_id_prime256v1:
   105				strcpy(alg_name, "ecdsa-nist-p256");
   106				return 0;
   107			default:
   108				return -EINVAL;
   109			}
   110		}
   111	
   112		return -ENOPKG;
   113	}
   114	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Stefan Berger Feb. 11, 2021, 5:30 p.m. UTC | #2
On 2/11/21 3:03 AM, kernel test robot wrote:
> Hi Stefan,

>

> Thank you for the patch! Yet something to improve:

>

>>> crypto/asymmetric_keys/public_key.c:97: undefined reference to `parse_OID'



So the issue is that  only ASYMMETRIC_PUBLIC_KEY_SUBTYPE is selected in 
this config and the selection of OID_REGISTRY is missing. I am not sure 
whether ASYMMETRIC_PUBLIC_KEY_SUBTYPE should/could select OID_REGISTRY 
or whether that would be wrong... ?


     Stefan
Stefan Berger Feb. 11, 2021, 6:18 p.m. UTC | #3
On 2/11/21 12:30 PM, Stefan Berger wrote:
> On 2/11/21 3:03 AM, kernel test robot wrote:

>> Hi Stefan,

>>

>> Thank you for the patch! Yet something to improve:

>>

>>>> crypto/asymmetric_keys/public_key.c:97: undefined reference to 

>>>> `parse_OID'

>

>

> So the issue is that  only ASYMMETRIC_PUBLIC_KEY_SUBTYPE is selected 

> in this config and the selection of OID_REGISTRY is missing. I am not 

> sure whether ASYMMETRIC_PUBLIC_KEY_SUBTYPE should/could select 

> OID_REGISTRY or whether that would be wrong... ?



David,

   if the above is not desired then the following change would let us 
get rid of the offending parse_OID(). The below change is only for NIST 
p192 in this experiment but shows that we need to add additional 
strcmp() cases in x509_check_for_self_signed() since 
cert->sig->pkey_algo is set to "ecdsa". I am not sure whether we should 
derive from the signature which curve was used to create the signature 
so that cert->sig->pkey_algo could be more specific and the simple 
existing strcmp() would pass. So two possible ways to go forward. Which 
way should we go?

    Stefan


diff --git a/crypto/asymmetric_keys/x509_cert_parser.c 
b/crypto/asymmetric_keys/x509_cert_parser.c
index 0aff4e584b11..71d83bb345c4 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -505,6 +505,8 @@ int x509_extract_key_data(void *context, size_t hdrlen,
                         ctx->cert->pub->pkey_algo = "sm2";
                         break;
                 case OID_id_prime192v1:
+                       ctx->cert->pub->pkey_algo = "ecdsa-nist-p192";
+                       break;
                 case OID_id_prime256v1:
                         ctx->cert->pub->pkey_algo = "ecdsa";
                         break;
diff --git a/crypto/asymmetric_keys/x509_public_key.c 
b/crypto/asymmetric_keys/x509_public_key.c
index ae450eb8be14..3ebeed195b61 100644
--- a/crypto/asymmetric_keys/x509_public_key.c
+++ b/crypto/asymmetric_keys/x509_public_key.c
@@ -129,7 +129,10 @@ int x509_check_for_self_signed(struct 
x509_certificate *cert)
         }

         ret = -EKEYREJECTED;
-       if (strcmp(cert->pub->pkey_algo, cert->sig->pkey_algo) != 0)
+printk(KERN_INFO "%s: %s ==? %s\n", __func__, cert->pub->pkey_algo, 
cert->sig->pkey_algo);
+       if (strcmp(cert->pub->pkey_algo, cert->sig->pkey_algo) != 0 &&
+           strncmp(cert->pub->pkey_algo, "ecdsa-nist-p", 12) != 0 &&
+           strcmp(cert->sig->pkey_algo, "ecdsa") != 0)
                 goto out;

         ret = public_key_verify_signature(cert->pub, cert->sig);


>

>

>     Stefan

>
diff mbox series

Patch

diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index 8892908ad58c..7dae61b79d5a 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -14,6 +14,7 @@ 
 #include <linux/slab.h>
 #include <linux/seq_file.h>
 #include <linux/scatterlist.h>
+#include <linux/asn1.h>
 #include <keys/asymmetric-subtype.h>
 #include <crypto/public_key.h>
 #include <crypto/akcipher.h>
@@ -90,6 +91,24 @@  int software_key_determine_akcipher(const char *encoding,
 		return 0;
 	}
 
+	if (strcmp(encoding, "x962") == 0) {
+		enum OID oid;
+
+		if (parse_OID(pkey->params, pkey->paramlen, &oid) != 0)
+			return -EBADMSG;
+
+		switch (oid) {
+		case OID_id_prime192v1:
+			strcpy(alg_name, "ecdsa-nist-p192");
+			return 0;
+		case OID_id_prime256v1:
+			strcpy(alg_name, "ecdsa-nist-p256");
+			return 0;
+		default:
+			return -EINVAL;
+		}
+	}
+
 	return -ENOPKG;
 }
 
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 1621ceaf5c95..0aff4e584b11 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -227,6 +227,26 @@  int x509_note_pkey_algo(void *context, size_t hdrlen,
 		ctx->cert->sig->hash_algo = "sha224";
 		goto rsa_pkcs1;
 
+	case OID_id_ecdsa_with_sha1:
+		ctx->cert->sig->hash_algo = "sha1";
+		goto ecdsa;
+
+	case OID_id_ecdsa_with_sha224:
+		ctx->cert->sig->hash_algo = "sha224";
+		goto ecdsa;
+
+	case OID_id_ecdsa_with_sha256:
+		ctx->cert->sig->hash_algo = "sha256";
+		goto ecdsa;
+
+	case OID_id_ecdsa_with_sha384:
+		ctx->cert->sig->hash_algo = "sha384";
+		goto ecdsa;
+
+	case OID_id_ecdsa_with_sha512:
+		ctx->cert->sig->hash_algo = "sha512";
+		goto ecdsa;
+
 	case OID_gost2012Signature256:
 		ctx->cert->sig->hash_algo = "streebog256";
 		goto ecrdsa;
@@ -255,6 +275,11 @@  int x509_note_pkey_algo(void *context, size_t hdrlen,
 	ctx->cert->sig->encoding = "raw";
 	ctx->algo_oid = ctx->last_oid;
 	return 0;
+ecdsa:
+	ctx->cert->sig->pkey_algo = "ecdsa";
+	ctx->cert->sig->encoding = "x962";
+	ctx->algo_oid = ctx->last_oid;
+	return 0;
 }
 
 /*
@@ -276,7 +301,8 @@  int x509_note_signature(void *context, size_t hdrlen,
 
 	if (strcmp(ctx->cert->sig->pkey_algo, "rsa") == 0 ||
 	    strcmp(ctx->cert->sig->pkey_algo, "ecrdsa") == 0 ||
-	    strcmp(ctx->cert->sig->pkey_algo, "sm2") == 0) {
+	    strcmp(ctx->cert->sig->pkey_algo, "sm2") == 0 ||
+	    strcmp(ctx->cert->sig->pkey_algo, "ecdsa") == 0) {
 		/* Discard the BIT STRING metadata */
 		if (vlen < 1 || *(const u8 *)value != 0)
 			return -EBADMSG;
@@ -478,6 +504,10 @@  int x509_extract_key_data(void *context, size_t hdrlen,
 		case OID_sm2:
 			ctx->cert->pub->pkey_algo = "sm2";
 			break;
+		case OID_id_prime192v1:
+		case OID_id_prime256v1:
+			ctx->cert->pub->pkey_algo = "ecdsa";
+			break;
 		default:
 			return -ENOPKG;
 		}
diff --git a/include/linux/oid_registry.h b/include/linux/oid_registry.h
index f3b2c097c886..ff3cad9f8c1f 100644
--- a/include/linux/oid_registry.h
+++ b/include/linux/oid_registry.h
@@ -21,6 +21,8 @@  enum OID {
 	OID_id_dsa,			/* 1.2.840.10040.4.1 */
 	OID_id_ecdsa_with_sha1,		/* 1.2.840.10045.4.1 */
 	OID_id_ecPublicKey,		/* 1.2.840.10045.2.1 */
+	OID_id_prime192v1,		/* 1.2.840.10045.3.1.1 */
+	OID_id_prime256v1,		/* 1.2.840.10045.3.1.7 */
 	OID_id_ecdsa_with_sha224,	/* 1.2.840.10045.4.3.1 */
 	OID_id_ecdsa_with_sha256,	/* 1.2.840.10045.4.3.2 */
 	OID_id_ecdsa_with_sha384,	/* 1.2.840.10045.4.3.3 */