Merge pull request #8608 from anhu/2akid

Check for duplicate extensions in a CRL

Author: douzzer

tests/api.c

@@ -4257,6 +4257,44 @@ static int test_wolfSSL_CertManagerNameConstraint5(void)
     return EXPECT_RESULT();
 }
 
+static int test_wolfSSL_CRL_duplicate_extensions(void)
+{
+    EXPECT_DECLS;
+#if defined(WOLFSSL_ASN_TEMPLATE) && !defined(NO_CERTS) && \
+    defined(HAVE_CRL) && !defined(NO_RSA) && !defined(WOLFSSL_NO_ASN_STRICT)
+    const unsigned char crl_duplicate_akd[] =
+        "-----BEGIN X509 CRL-----\n"
+        "MIICCDCB8QIBATANBgkqhkiG9w0BAQsFADB5MQswCQYDVQQGEwJVUzETMBEGA1UE\n"
+        "CAwKQ2FsaWZvcm5pYTEWMBQGA1UEBwwNU2FuIEZyYW5jaXNjbzETMBEGA1UECgwK\n"
+        "TXkgQ29tcGFueTETMBEGA1UEAwwKTXkgUm9vdCBDQTETMBEGA1UECwwKTXkgUm9v\n"
+        "dCBDQRcNMjQwOTAxMDAwMDAwWhcNMjUxMjAxMDAwMDAwWqBEMEIwHwYDVR0jBBgw\n"
+        "FoAU72ng99Ud5pns3G3Q9+K5XGRxgzUwHwYDVR0jBBgwFoAU72ng99Ud5pns3G3Q\n"
+        "9+K5XGRxgzUwDQYJKoZIhvcNAQELBQADggEBAIFVw4jrS4taSXR/9gPzqGrqFeHr\n"
+        "IXCnFtHJTLxqa8vUOAqSwqysvNpepVKioMVoGrLjFMjANjWQqTEiMROAnLfJ/+L8\n"
+        "FHZkV/mZwOKAXMhIC9MrJzifxBICwmvD028qnwQm09EP8z4ICZptD6wPdRTDzduc\n"
+        "KBuAX+zn8pNrJgyrheRKpPgno9KsbCzK4D/RIt1sTK2M3vVOtY+vpsN70QYUXvQ4\n"
+        "r2RZac3omlT43x5lddPxIlcouQpwWcVvr/K+Va770MRrjn88PBrJmvsEw/QYVBXp\n"
+        "Gxv2b78HFDacba80sMIm8ltRdqUCa5qIc6OATsz7izCQXEbkTEeESrcK1MA=\n"
+        "-----END X509 CRL-----\n";
+
+    WOLFSSL_CERT_MANAGER* cm = NULL;
+    int ret;
+
+    cm = wolfSSL_CertManagerNew();
+    ExpectNotNull(cm);
+
+    /* Test loading CRL with duplicate extensions */
+    WOLFSSL_MSG("Testing CRL with duplicate Authority Key Identifier extensions");
+    ret = wolfSSL_CertManagerLoadCRLBuffer(cm, crl_duplicate_akd,
+                                           sizeof(crl_duplicate_akd),
+                                           WOLFSSL_FILETYPE_PEM);
+    ExpectIntEQ(ret, ASN_PARSE_E);
+
+    wolfSSL_CertManagerFree(cm);
+#endif
+    return EXPECT_RESULT();
+}
+
 static int test_wolfSSL_CertManagerCRL(void)
 {
     EXPECT_DECLS;
@@ -68150,6 +68188,7 @@ TEST_CASE testCases[] = {
     TEST_DECL(test_wolfSSL_CertManagerNameConstraint4),
     TEST_DECL(test_wolfSSL_CertManagerNameConstraint5),
     TEST_DECL(test_wolfSSL_CertManagerCRL),
+    TEST_DECL(test_wolfSSL_CRL_duplicate_extensions),
     TEST_DECL(test_wolfSSL_CertManagerCheckOCSPResponse),
     TEST_DECL(test_wolfSSL_CheckOCSPResponse),
 #ifdef HAVE_CERT_CHAIN_VALIDATION

wolfcrypt/src/asn.c

@@ -40566,6 +40566,9 @@ static int ParseCRL_Extensions(DecodedCRL* dcrl, const byte* buf, word32 idx,
 {
     DECL_ASNGETDATA(dataASN, certExtASN_Length);
     int ret = 0;
+    /* Track if we've seen these extensions already */
+    word32 seenAuthKey = 0;
+    word32 seenCrlNum = 0;
 
     ALLOC_ASNGETDATA(dataASN, certExtASN_Length, ret, dcrl->heap);
 
@@ -40588,47 +40591,71 @@ static int ParseCRL_Extensions(DecodedCRL* dcrl, const byte* buf, word32 idx,
             /* Length of extension data. */
             int length = (int)dataASN[CERTEXTASN_IDX_VAL].length;
 
-            if (oid == AUTH_KEY_OID) {
-            #ifndef NO_SKID
-                /* Parse Authority Key Id extension.
-                 * idx is at start of OCTET_STRING data. */
-                ret = ParseCRL_AuthKeyIdExt(buf + localIdx, length, dcrl);
-                if (ret != 0) {
-                    WOLFSSL_MSG("\tcouldn't parse AuthKeyId extension");
-                }
-            #endif
+            /* Check for duplicate extension. RFC 5280 Section 4.2 states that
+             * a certificate must not include more than one instance of a
+             * particular extension. Note that the same guidance does not appear
+             * for CRLs but the same reasoning should apply. */
+            if ((oid == AUTH_KEY_OID && seenAuthKey) ||
+                (oid == CRL_NUMBER_OID && seenCrlNum)) {
+                WOLFSSL_MSG("Duplicate CRL extension found");
+                /* Gating !WOLFSSL_NO_ASN_STRICT will allow wolfCLU to have same
+                 * behaviour as OpenSSL */
+#ifndef WOLFSSL_NO_ASN_STRICT
+                ret = ASN_PARSE_E;
+#endif
             }
-            else if (oid == CRL_NUMBER_OID) {
-                DECL_MP_INT_SIZE_DYN(m, CRL_MAX_NUM_SZ * CHAR_BIT,
-                               CRL_MAX_NUM_SZ * CHAR_BIT);
-                NEW_MP_INT_SIZE(m, CRL_MAX_NUM_SZ * CHAR_BIT, NULL,
-                               DYNAMIC_TYPE_TMP_BUFFER);
 
-            #ifdef MP_INT_SIZE_CHECK_NULL
-                if (m == NULL) {
-                    ret = MEMORY_E;
+            /* Track this extension if no duplicate found */
+            if (ret == 0) {
+                if (oid == AUTH_KEY_OID)
+                    seenAuthKey = 1;
+                else if (oid == CRL_NUMBER_OID)
+                    seenCrlNum = 1;
+            }
+
+            if (ret == 0) {
+                if (oid == AUTH_KEY_OID) {
+                #ifndef NO_SKID
+                    /* Parse Authority Key Id extension.
+                     * idx is at start of OCTET_STRING data. */
+                    ret = ParseCRL_AuthKeyIdExt(buf + localIdx, length, dcrl);
+                    if (ret != 0) {
+                        WOLFSSL_MSG("\tcouldn't parse AuthKeyId extension");
+                    }
+                #endif
                 }
-            #endif
+                else if (oid == CRL_NUMBER_OID) {
+                    DECL_MP_INT_SIZE_DYN(m, CRL_MAX_NUM_SZ * CHAR_BIT,
+                                   CRL_MAX_NUM_SZ * CHAR_BIT);
+                    NEW_MP_INT_SIZE(m, CRL_MAX_NUM_SZ * CHAR_BIT, NULL,
+                                   DYNAMIC_TYPE_TMP_BUFFER);
+
+                #ifdef MP_INT_SIZE_CHECK_NULL
+                    if (m == NULL) {
+                        ret = MEMORY_E;
+                    }
+                #endif
 
-                if (ret == 0 && (INIT_MP_INT_SIZE(m, CRL_MAX_NUM_SZ * CHAR_BIT)
-                             != MP_OKAY)) {
+                    if (ret == 0 && (INIT_MP_INT_SIZE(m, CRL_MAX_NUM_SZ *
+                        CHAR_BIT) != MP_OKAY)) {
                         ret = MP_INIT_E;
-                }
+                    }
 
-                if (ret == 0) {
-                    ret = GetInt(m, buf, &localIdx, maxIdx);
-                }
+                    if (ret == 0) {
+                        ret = GetInt(m, buf, &localIdx, maxIdx);
+                    }
 
-                if (ret == 0 && mp_toradix(m, (char*)dcrl->crlNumber,
-                             MP_RADIX_HEX) != MP_OKAY)
-                    ret = BUFFER_E;
+                    if (ret == 0 && mp_toradix(m, (char*)dcrl->crlNumber,
+                                 MP_RADIX_HEX) != MP_OKAY)
+                        ret = BUFFER_E;
 
-                if (ret == 0) {
-                    dcrl->crlNumberSet = 1;
-                }
+                    if (ret == 0) {
+                        dcrl->crlNumberSet = 1;
+                    }
 
-                mp_free(m);
-                FREE_MP_INT_SIZE(m, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+                    mp_free(m);
+                    FREE_MP_INT_SIZE(m, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+                }
             }
             /* TODO: check criticality */
             /* Move index on to next extension. */