From df7c2f7e4f426310e29c5b74fcf143ddb9fb7224 Mon Sep 17 00:00:00 2001
From: nzsquirrell <nzsquirrell@users.noreply.github.com>
Date: Fri, 28 Aug 2015 19:56:52 +1200
Subject: [PATCH] fix failed tests and issues with versions of openssl

changes sourced from:
https://github.com/bitcoin/bitcoin/commit/b8e81b7ccd4490155e3345fc73346ff8c3a77524
https://github.com/bitcoin/bitcoin/commit/60c51f1c381bbd93c70cfdf41c6688609a7956fc
https://github.com/bitcoin/bitcoin/commit/037bfefe6bccbdf656e628a1f4526db8f80c3922
---
 src/key.cpp | 32 ++++++++++++++++++++++++++++----
 1 file changed, 28 insertions(+), 4 deletions(-)

diff --git a/src/key.cpp b/src/key.cpp
index 71a8bd27..6a502e62 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -227,11 +227,35 @@ public:
     }
 
     bool Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) {
+		if (vchSig.empty())
+			return false;
+		
+		// New versions of OpenSSL will reject non-canonical DER signatures. de/re-serialize first.
+		unsigned char *norm_der = NULL;
+		ECDSA_SIG *norm_sig = ECDSA_SIG_new();
+		const unsigned char* sigptr = &vchSig[0];
+		assert(norm_sig);
+		if (d2i_ECDSA_SIG(&norm_sig, &sigptr, vchSig.size()) == NULL)
+		{
+			/* As of OpenSSL 1.0.0p d2i_ECDSA_SIG frees and nulls the pointer on
+			 * error. But OpenSSL's own use of this function redundantly frees the
+             * result. As ECDSA_SIG_free(NULL) is a no-op, and in the absence of a
+             * clear contract for the function behaving the same way is more
+             * conservative.
+             */
+			 ECDSA_SIG_free(norm_sig);
+			 return false;
+		}
+		int derlen = i2d_ECDSA_SIG(norm_sig, &norm_der);
+		ECDSA_SIG_free(norm_sig);
+		if (derlen <= 0)
+			return false;
+		
         // -1 = error, 0 = bad sig, 1 = good
-        if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1)
-            return false;
-        return true;
-    }
+		bool ret = ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), norm_der, derlen, pkey) == 1;
+		OPENSSL_free(norm_der);
+		return ret;
+	}
 
     bool SignCompact(const uint256 &hash, unsigned char *p64, int &rec) {
         bool fOk = false;