X-Git-Url: https://git.novaco.in/?a=blobdiff_plain;f=src%2Fkey.cpp;h=6239ba5712e1c848c7f0d8d23fa71b804c53cecd;hb=afc2bcf340f842111978138a9e04e0b14e5de9fe;hp=4a7d7fd02803b10e0dbaa4a0cebadaa8b3c856fb;hpb=07bc41cd07f81fffadcf5b0fb8838e84a159389e;p=novacoin.git

diff --git a/src/key.cpp b/src/key.cpp
index 4a7d7fd..6239ba5 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -161,7 +161,7 @@ const unsigned char vchMaxModHalfOrder[32] = {
     0xDF,0xE9,0x2F,0x46,0x68,0x1B,0x20,0xA0
 };
 
-const unsigned char vchZero[0] = {};
+const unsigned char *vchZero = NULL;
 
 
 
@@ -224,6 +224,32 @@ bool CKey::CheckSignatureElement(const unsigned char *vch, int len, bool half) {
         CompareBigEndian(vch, len, half ? vchMaxModHalfOrder : vchMaxModOrder, 32) <= 0;
 }
 
+bool CKey::ReserealizeSignature(std::vector<unsigned char>& vchSig)
+{
+    if (vchSig.empty())
+        return false;
+
+    unsigned char *pos = &vchSig[0];
+    ECDSA_SIG *sig = d2i_ECDSA_SIG(NULL, (const unsigned char **)&pos, vchSig.size());
+    if (sig == NULL)
+        return false;
+
+    bool ret = false;
+    int nSize = i2d_ECDSA_SIG(sig, NULL);
+    if (nSize > 0) {
+        vchSig.resize(nSize); // grow or shrink as needed
+
+        pos = &vchSig[0];
+        i2d_ECDSA_SIG(sig, &pos);
+
+        ret = true;
+    }
+
+    ECDSA_SIG_free(sig);
+
+    return ret;
+}
+
 void CKey::MakeNewKey(bool fCompressed)
 {
     if (!EC_KEY_generate_key(pkey))
@@ -344,7 +370,7 @@ bool CKey::Sign(uint256 hash, std::vector<unsigned char>& vchSig)
     EC_GROUP_get_order(group, &order, NULL);
     BN_rshift1(&halforder, &order);
     // enforce low S values, by negating the value (modulo the order) if above order/2.
-    if (BN_cmp(sig->s, &halforder)) {
+    if (BN_cmp(sig->s, &halforder) > 0) {
         BN_sub(sig->s, &order, sig->s);
     }
     unsigned int nSize = ECDSA_size(pkey);
@@ -376,7 +402,7 @@ bool CKey::SignCompact(uint256 hash, std::vector<unsigned char>& vchSig)
     EC_GROUP_get_order(group, &order, NULL);
     BN_rshift1(&halforder, &order);
     // enforce low S values, by negating the value (modulo the order) if above order/2.
-    if (BN_cmp(sig->s, &halforder)) {
+    if (BN_cmp(sig->s, &halforder) > 0) {
         BN_sub(sig->s, &order, sig->s);
     }
     vchSig.clear();
@@ -385,8 +411,8 @@ bool CKey::SignCompact(uint256 hash, std::vector<unsigned char>& vchSig)
     int nBitsS = BN_num_bits(sig->s);
     if (nBitsR <= 256 && nBitsS <= 256)
     {
-        int nRecId = -1;
-        for (int i=0; i<4; i++)
+        int8_t nRecId = -1;
+        for (int8_t i=0; i<4; i++)
         {
             CKey keyRec;
             keyRec.fSet = true;
@@ -449,11 +475,34 @@ bool CKey::SetCompactSignature(uint256 hash, const std::vector<unsigned char>& v
 
 bool CKey::Verify(uint256 hash, const std::vector<unsigned char>& vchSig)
 {
-    // -1 = error, 0 = bad sig, 1 = good
-    if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1)
+    if (vchSig.empty())
         return false;
 
-    return true;
+    // 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
+    bool ret = ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), norm_der, derlen, pkey) == 1;
+    OPENSSL_free(norm_der);
+    return ret;
 }
 
 bool CKey::VerifyCompact(uint256 hash, const std::vector<unsigned char>& vchSig)