CPubKey::Verify() : Fix memory leak.

[novacoin.git] / src / key.cpp

diff --git a/src/key.cpp b/src/key.cpp
index 2c3a849..c68fcda 100644 (file)
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -497,35 +497,37 @@ bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchS
     if (vchSig.empty() || !IsValid())
         return false;
 
-    const unsigned char* pbegin = &vbytes[0];
     EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
-    if (!o2i_ECPublicKey(&pkey, &pbegin, size()))
-        return false; // Unable to parse public key
-
-    // 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)
+    assert(pkey);
+
+    bool ret = false;
+    do
     {
-        /* 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);
+        int derlen;
+        uint8_t *norm_der = NULL;
+        const uint8_t* pbegin = &vbytes[0];
+        const uint8_t* sigptr = &vchSig[0];
+
+        // Trying to parse public key
+        if (!o2i_ECPublicKey(&pkey, &pbegin, size()))
+            break;
+        // New versions of OpenSSL are rejecting a non-canonical DER signatures, de/re-serialize first.
+        if (d2i_ECDSA_SIG(&norm_sig, &sigptr, vchSig.size()) == NULL)
+            break;
+        if ((derlen = i2d_ECDSA_SIG(norm_sig, &norm_der)) <= 0)
+            break;
+
+        // -1 = error, 0 = bad sig, 1 = good
+        ret = ECDSA_verify(0, hash.begin(), hash.size(), norm_der, derlen, pkey) == 1;
+        OPENSSL_free(norm_der);
+    } while(false);
+
     ECDSA_SIG_free(norm_sig);
-    if (derlen <= 0)
-        return false;
+    EC_KEY_free(pkey);
 
-    // -1 = error, 0 = bad sig, 1 = good
-    bool ret = ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), norm_der, derlen, pkey) == 1;
-    OPENSSL_free(norm_der);
     return ret;
 }