1 files changed, 221 insertions, 0 deletions
diff --git a/src/key.cpp b/src/key.cpp
new file mode 100644
index 0000000000..acf62360a4
--- /dev/null
+++ b/src/key.cpp
@@ -0,0 +1,221 @@
+// Copyright (c) 2009-2014 The Bitcoin developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "key.h"
+
+#include "crypto/hmac_sha512.h"
+#include "crypto/rfc6979_hmac_sha256.h"
+#include "eccryptoverify.h"
+#include "pubkey.h"
+#include "random.h"
+
+#include <secp256k1.h>
+#include "ecwrapper.h"
+
+//! anonymous namespace
+namespace {
+
+class CSecp256k1Init {
+public:
+    CSecp256k1Init() {
+        secp256k1_start(SECP256K1_START_SIGN);
+    }
+    ~CSecp256k1Init() {
+        secp256k1_stop();
+    }
+};
+static CSecp256k1Init instance_of_csecp256k1;
+
+} // anon namespace
+
+bool CKey::Check(const unsigned char *vch) {
+    return eccrypto::Check(vch);
+}
+
+void CKey::MakeNewKey(bool fCompressedIn) {
+    do {
+        GetRandBytes(vch, sizeof(vch));
+    } while (!Check(vch));
+    fValid = true;
+    fCompressed = fCompressedIn;
+}
+
+bool CKey::SetPrivKey(const CPrivKey &privkey, bool fCompressedIn) {
+    if (!secp256k1_ec_privkey_import((unsigned char*)begin(), &privkey[0], privkey.size()))
+        return false;
+    fCompressed = fCompressedIn;
+    fValid = true;
+    return true;
+}
+
+CPrivKey CKey::GetPrivKey() const {
+    assert(fValid);
+    CPrivKey privkey;
+    int privkeylen, ret;
+    privkey.resize(279);
+    privkeylen = 279;
+    ret = secp256k1_ec_privkey_export(begin(), (unsigned char*)&privkey[0], &privkeylen, fCompressed);
+    assert(ret);
+    privkey.resize(privkeylen);
+    return privkey;
+}
+
+CPubKey CKey::GetPubKey() const {
+    assert(fValid);
+    CPubKey result;
+    int clen = 65;
+    int ret = secp256k1_ec_pubkey_create((unsigned char*)result.begin(), &clen, begin(), fCompressed);
+    assert((int)result.size() == clen);
+    assert(ret);
+    assert(result.IsValid());
+    return result;
+}
+
+bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, uint32_t test_case) const {
+    if (!fValid)
+        return false;
+    vchSig.resize(72);
+    RFC6979_HMAC_SHA256 prng(begin(), 32, (unsigned char*)&hash, 32);
+    do {
+        uint256 nonce;
+        prng.Generate((unsigned char*)&nonce, 32);
+        nonce += test_case;
+        int nSigLen = 72;
+        int ret = secp256k1_ecdsa_sign((const unsigned char*)&hash, 32, (unsigned char*)&vchSig[0], &nSigLen, begin(), (unsigned char*)&nonce);
+        nonce = 0;
+        if (ret) {
+            vchSig.resize(nSigLen);
+            return true;
+        }
+    } while(true);
+}
+
+bool CKey::VerifyPubKey(const CPubKey& pubkey) const {
+    if (pubkey.IsCompressed() != fCompressed) {
+        return false;
+    }
+    unsigned char rnd[8];
+    std::string str = "Bitcoin key verification\n";
+    GetRandBytes(rnd, sizeof(rnd));
+    uint256 hash;
+    CHash256().Write((unsigned char*)str.data(), str.size()).Write(rnd, sizeof(rnd)).Finalize((unsigned char*)&hash);
+    std::vector<unsigned char> vchSig;
+    Sign(hash, vchSig);
+    return pubkey.Verify(hash, vchSig);
+}
+
+bool CKey::SignCompact(const uint256 &hash, std::vector<unsigned char>& vchSig) const {
+    if (!fValid)
+        return false;
+    vchSig.resize(65);
+    int rec = -1;
+    RFC6979_HMAC_SHA256 prng(begin(), 32, (unsigned char*)&hash, 32);
+    do {
+        uint256 nonce;
+        prng.Generate((unsigned char*)&nonce, 32);
+        int ret = secp256k1_ecdsa_sign_compact((const unsigned char*)&hash, 32, &vchSig[1], begin(), (unsigned char*)&nonce, &rec);
+        nonce = 0;
+        if (ret)
+            break;
+    } while(true);
+    assert(rec != -1);
+    vchSig[0] = 27 + rec + (fCompressed ? 4 : 0);
+    return true;
+}
+
+bool CKey::Load(CPrivKey &privkey, CPubKey &vchPubKey, bool fSkipCheck=false) {
+    if (!secp256k1_ec_privkey_import((unsigned char*)begin(), &privkey[0], privkey.size()))
+        return false;
+    fCompressed = vchPubKey.IsCompressed();
+    fValid = true;
+
+    if (fSkipCheck)
+        return true;
+
+    return VerifyPubKey(vchPubKey);
+}
+
+bool CKey::Derive(CKey& keyChild, unsigned char ccChild[32], unsigned int nChild, const unsigned char cc[32]) const {
+    assert(IsValid());
+    assert(IsCompressed());
+    unsigned char out[64];
+    LockObject(out);
+    if ((nChild >> 31) == 0) {
+        CPubKey pubkey = GetPubKey();
+        assert(pubkey.begin() + 33 == pubkey.end());
+        BIP32Hash(cc, nChild, *pubkey.begin(), pubkey.begin()+1, out);
+    } else {
+        assert(begin() + 32 == end());
+        BIP32Hash(cc, nChild, 0, begin(), out);
+    }
+    memcpy(ccChild, out+32, 32);
+    memcpy((unsigned char*)keyChild.begin(), begin(), 32);
+    bool ret = secp256k1_ec_privkey_tweak_add((unsigned char*)keyChild.begin(), out);
+    UnlockObject(out);
+    keyChild.fCompressed = true;
+    keyChild.fValid = ret;
+    return ret;
+}
+
+bool CExtKey::Derive(CExtKey &out, unsigned int nChild) const {
+    out.nDepth = nDepth + 1;
+    CKeyID id = key.GetPubKey().GetID();
+    memcpy(&out.vchFingerprint[0], &id, 4);
+    out.nChild = nChild;
+    return key.Derive(out.key, out.vchChainCode, nChild, vchChainCode);
+}
+
+void CExtKey::SetMaster(const unsigned char *seed, unsigned int nSeedLen) {
+    static const unsigned char hashkey[] = {'B','i','t','c','o','i','n',' ','s','e','e','d'};
+    unsigned char out[64];
+    LockObject(out);
+    CHMAC_SHA512(hashkey, sizeof(hashkey)).Write(seed, nSeedLen).Finalize(out);
+    key.Set(&out[0], &out[32], true);
+    memcpy(vchChainCode, &out[32], 32);
+    UnlockObject(out);
+    nDepth = 0;
+    nChild = 0;
+    memset(vchFingerprint, 0, sizeof(vchFingerprint));
+}
+
+CExtPubKey CExtKey::Neuter() const {
+    CExtPubKey ret;
+    ret.nDepth = nDepth;
+    memcpy(&ret.vchFingerprint[0], &vchFingerprint[0], 4);
+    ret.nChild = nChild;
+    ret.pubkey = key.GetPubKey();
+    memcpy(&ret.vchChainCode[0], &vchChainCode[0], 32);
+    return ret;
+}
+
+void CExtKey::Encode(unsigned char code[74]) const {
+    code[0] = nDepth;
+    memcpy(code+1, vchFingerprint, 4);
+    code[5] = (nChild >> 24) & 0xFF; code[6] = (nChild >> 16) & 0xFF;
+    code[7] = (nChild >>  8) & 0xFF; code[8] = (nChild >>  0) & 0xFF;
+    memcpy(code+9, vchChainCode, 32);
+    code[41] = 0;
+    assert(key.size() == 32);
+    memcpy(code+42, key.begin(), 32);
+}
+
+void CExtKey::Decode(const unsigned char code[74]) {
+    nDepth = code[0];
+    memcpy(vchFingerprint, code+1, 4);
+    nChild = (code[5] << 24) | (code[6] << 16) | (code[7] << 8) | code[8];
+    memcpy(vchChainCode, code+9, 32);
+    key.Set(code+42, code+74, true);
+}
+
+bool ECC_InitSanityCheck() {
+#if !defined(USE_SECP256K1)
+    if (!CECKey::SanityCheck()) {
+        return false;
+    }
+#endif
+    CKey key;
+    key.MakeNewKey(true);
+    CPubKey pubkey = key.GetPubKey();
+    return key.VerifyPubKey(pubkey);
+}