Add Version Check for CSR Verification

Fixes #5738: This change introduces a check for the version number of a CSR document before its signature is verified. If the version number is not 1 (encoded as zero), the verification function fails with an `X509_R_UNSUPPORTED_VERSION` error.

To minimize impact, this check is only applied when verifying a certificate signing request using the `-verify` argument, resulting in a `X509_REQ_verify` call. This ensures that malformed certificate requests are rejected by a certification authority, enhancing security and preventing potential issues.

Reviewed-by: Neil Horman <nhorman@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/24677)

diff --git a/crypto/err/openssl.txt b/crypto/err/openssl.txt
index 3279f49199f8994fe34707935554a103f23ced59..93dfbeeea5ef003780126574b386b77b3e43f66f 100644 (file)
--- a/crypto/err/openssl.txt
+++ b/crypto/err/openssl.txt
@@ -1841,5 +1841,6 @@ X509_R_UNKNOWN_PURPOSE_ID:121:unknown purpose id
 X509_R_UNKNOWN_SIGID_ALGS:144:unknown sigid algs
 X509_R_UNKNOWN_TRUST_ID:120:unknown trust id
 X509_R_UNSUPPORTED_ALGORITHM:111:unsupported algorithm
+X509_R_UNSUPPORTED_VERSION:145:unsupported version
 X509_R_WRONG_LOOKUP_TYPE:112:wrong lookup type
 X509_R_WRONG_TYPE:122:wrong type

diff --git a/crypto/x509/x509_err.c b/crypto/x509/x509_err.c
index 226e45a737b853133de99bb267fd57dd44e615a3..607d38f3be3c250c28cc30f2676baa93ff324d81 100644 (file)
--- a/crypto/x509/x509_err.c
+++ b/crypto/x509/x509_err.c
@@ -1,6 +1,6 @@
 /*
  * Generated by util/mkerr.pl DO NOT EDIT
- * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2024 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -79,6 +79,8 @@ static const ERR_STRING_DATA X509_str_reasons[] = {
     {ERR_PACK(ERR_LIB_X509, 0, X509_R_UNKNOWN_TRUST_ID), "unknown trust id"},
     {ERR_PACK(ERR_LIB_X509, 0, X509_R_UNSUPPORTED_ALGORITHM),
     "unsupported algorithm"},
+    {ERR_PACK(ERR_LIB_X509, 0, X509_R_UNSUPPORTED_VERSION),
+    "unsupported version"},
     {ERR_PACK(ERR_LIB_X509, 0, X509_R_WRONG_LOOKUP_TYPE), "wrong lookup type"},
     {ERR_PACK(ERR_LIB_X509, 0, X509_R_WRONG_TYPE), "wrong type"},
     {0, NULL}

diff --git a/crypto/x509/x_all.c b/crypto/x509/x_all.c
index 3083eb1dca9b737da1e58faa0cec66000a468f2c..55d3dca1f2d9408b817ed6ecb96b78890d62485a 100644 (file)
--- a/crypto/x509/x_all.c
+++ b/crypto/x509/x_all.c
@@ -43,6 +43,11 @@ int X509_verify(X509 *a, EVP_PKEY *r)
 int X509_REQ_verify_ex(X509_REQ *a, EVP_PKEY *r, OSSL_LIB_CTX *libctx,
                        const char *propq)
 {
+    if (X509_REQ_get_version(a) != X509_REQ_VERSION_1) {
+        ERR_raise(ERR_LIB_X509, X509_R_UNSUPPORTED_VERSION);
+        return -1;
+    }
+
     return ASN1_item_verify_ex(ASN1_ITEM_rptr(X509_REQ_INFO), &a->sig_alg,
                                a->signature, &a->req_info, a->distinguishing_id,
                                r, libctx, propq);

diff --git a/include/openssl/x509err.h b/include/openssl/x509err.h
index 71b557a3e6b37beab4aeb29f8963765f41f89e3c..77b91c8b2cff34c1217de078398fbfea00616a1b 100644 (file)
--- a/include/openssl/x509err.h
+++ b/include/openssl/x509err.h
@@ -1,6 +1,6 @@
 /*
  * Generated by util/mkerr.pl DO NOT EDIT
- * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2024 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the Apache License 2.0 (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -63,6 +63,7 @@
 # define X509_R_UNKNOWN_SIGID_ALGS                        144
 # define X509_R_UNKNOWN_TRUST_ID                          120
 # define X509_R_UNSUPPORTED_ALGORITHM                     111
+# define X509_R_UNSUPPORTED_VERSION                       145
 # define X509_R_WRONG_LOOKUP_TYPE                         112
 # define X509_R_WRONG_TYPE                                122