Fix EVP_DigestInit_ex with NULL digest

Calling EVP_DigestInit_ex which has already had the digest set up for it
should be possible. You are supposed to be able to pass NULL for the type.
However currently this seg faults.

Reviewed-by: Andy Polyakov <appro@openssl.org>
(cherry picked from commit a01087027bd0c5ec053d4eabd972bd942bfcd92f)

diff --git a/crypto/evp/digest.c b/crypto/evp/digest.c
index bd7760d0c977a9ea55fd64b5df1ebe7883d6250c..f2643f32486ad2637d6f328cb860f380f2dff1f5 100644 (file)
--- a/crypto/evp/digest.c
+++ b/crypto/evp/digest.c
@@ -203,9 +203,12 @@ int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
             ctx->engine = impl;
         } else
             ctx->engine = NULL;
-    } else if (!ctx->digest) {
-        EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_NO_DIGEST_SET);
-        return 0;
+    } else {
+        if (!ctx->digest) {
+            EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_NO_DIGEST_SET);
+            return 0;
+        }
+        type = ctx->digest;
     }
 #endif
     if (ctx->digest != type) {