Modify verify code to handle self signed certificates.

[openssl.git] / crypto / x509 / x509_vfy.c

diff --git a/crypto/x509/x509_vfy.c b/crypto/x509/x509_vfy.c
index def60ef23e715f7d39a6cd6a0b9b0b8071e83280..97984cade4b2c2f059c5c2599f7872b2ae4df4c9 100644 (file)
--- a/crypto/x509/x509_vfy.c
+++ b/crypto/x509/x509_vfy.c
@@ -125,7 +125,7 @@ int X509_verify_cert(X509_STORE_CTX *ctx)
                ctx->last_untrusted=1;
                }
 
-       /* We use a temporary so we can chop and hack at it */
+       /* We use a temporary STACK so we can chop and hack at it */
        if (ctx->untrusted != NULL
            && (sktmp=sk_X509_dup(ctx->untrusted)) == NULL)
                {
@@ -182,17 +182,37 @@ int X509_verify_cert(X509_STORE_CTX *ctx)
 
        i=sk_X509_num(ctx->chain);
        x=sk_X509_value(ctx->chain,i-1);
-       if (X509_NAME_cmp(X509_get_subject_name(x),X509_get_issuer_name(x))
+       xn = X509_get_subject_name(x);
+       if (X509_NAME_cmp(xn,X509_get_issuer_name(x))
                == 0)
                {
                /* we have a self signed certificate */
                if (sk_X509_num(ctx->chain) == 1)
                        {
-                       ctx->error=X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
-                       ctx->current_cert=x;
-                       ctx->error_depth=i-1;
-                       ok=cb(0,ctx);
-                       if (!ok) goto end;
+                       /* We have a single self signed certificate: see if
+                        * we can find it in the store. We must have an exact
+                        * match to avoid possible impersonation.
+                        */
+                       ok=X509_STORE_get_by_subject(ctx,X509_LU_X509,xn,&obj);
+                       if ((ok != X509_LU_X509) || X509_cmp(x, obj.data.x509)) 
+                               {
+                               ctx->error=X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT;
+                               ctx->current_cert=x;
+                               ctx->error_depth=i-1;
+                               if(ok == X509_LU_X509) X509_OBJECT_free_contents(&obj);
+                               ok=cb(0,ctx);
+                               if (!ok) goto end;
+                               }
+                       else 
+                               {
+                               /* We have a match: replace certificate with store version
+                                * so we get any trust settings.
+                                */
+                               X509_free(x);
+                               x = obj.data.x509;
+                               sk_X509_set(ctx->chain, i - 1, x);
+                               ctx->last_untrusted=0;
+                               }
                        }
                else
                        {