!97 fix CVE-2023-0465 CVE-2023-0466

Merge pull request !97 from code4lala/fix-CVE-2023-0465-CVE-2023-0466

CHANGES

@@ -9,6 +9,11 @@
 
  Changes between 1.1.1s and 1.1.1t [xx XXX xxxx]
 
+  *) Corrected documentation of X509_VERIFY_PARAM_add0_policy() to mention
+     that it does not enable policy checking. Thanks to
+     David Benjamin for discovering this issue. (CVE-2023-0466)
+     [Tomas Mraz]
+
   *) Fixed a type confusion vulnerability relating to X.400 address processing
      inside an X.509 GeneralName. X.400 addresses were parsed as an ASN1_STRING
      but subsequently interpreted by GENERAL_NAME_cmp as an ASN1_TYPE. This

NEWS

@@ -4,6 +4,7 @@
 
   This file gives a brief overview of the major changes between each OpenSSL
   release. For more details please read the CHANGES file.
+      o Fixed documentation of X509_VERIFY_PARAM_add0_policy() (CVE-2023-0466)
 
   Major changes between OpenSSL 1.1.1m and OpenSSL 1.1.1n [15 Mar 2022]
 

crypto/x509/x509_vfy.c

@@ -1649,18 +1649,25 @@ static int check_policy(X509_STORE_CTX *ctx)
     }
     /* Invalid or inconsistent extensions */
     if (ret == X509_PCY_TREE_INVALID) {
-        int i;
+        int i, cbcalled = 0;
 
         /* Locate certificates with bad extensions and notify callback. */
-        for (i = 1; i < sk_X509_num(ctx->chain); i++) {
+        for (i = 0; i < sk_X509_num(ctx->chain); i++) {
             X509 *x = sk_X509_value(ctx->chain, i);
 
             if (!(x->ex_flags & EXFLAG_INVALID_POLICY))
                 continue;
+            cbcalled = 1;
             if (!verify_cb_cert(ctx, x, i,
                                 X509_V_ERR_INVALID_POLICY_EXTENSION))
                 return 0;
         }
+        if (!cbcalled) {
+            /* Should not be able to get here */
+            X509err(X509_F_CHECK_POLICY, ERR_R_INTERNAL_ERROR);
+            return 0;
+        }
+        /* The callback ignored the error so we return success */
         return 1;
     }
     if (ret == X509_PCY_TREE_FAILURE) {

doc/man3/X509_VERIFY_PARAM_set_flags.pod

@@ -92,8 +92,9 @@ B<trust>.
 X509_VERIFY_PARAM_set_time() sets the verification time in B<param> to
 B<t>. Normally the current time is used.
 
-X509_VERIFY_PARAM_add0_policy() enables policy checking (it is disabled
-by default) and adds B<policy> to the acceptable policy set.
+X509_VERIFY_PARAM_add0_policy() adds B<policy> to the acceptable policy set.
+Contrary to preexisting documentation of this function it does not enable
+policy checking.
 
 X509_VERIFY_PARAM_set1_policies() enables policy checking (it is disabled
 by default) and sets the acceptable policy set to B<policies>. Any existing
@@ -377,6 +378,10 @@ and has no effect.
 
 The X509_VERIFY_PARAM_get_hostflags() function was added in OpenSSL 1.1.0i.
 
+The function X509_VERIFY_PARAM_add0_policy() was historically documented as
+enabling policy checking however the implementation has never done this.
+The documentation was changed to align with the implementation.
+
 =head1 COPYRIGHT
 
 Copyright 2009-2020 The OpenSSL Project Authors. All Rights Reserved.