1 files changed, 223 insertions, 0 deletions
diff --git a/src/key.cpp b/src/key.cpp
new file mode 100644
index 0000000000..b772dff333
--- /dev/null
+++ b/src/key.cpp
@@ -0,0 +1,223 @@
+// Copyright (c) 2009-2014 The Bitcoin Core 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 "arith_uint256.h"
+#include "crypto/common.h"
+#include "crypto/hmac_sha512.h"
+#include "eccryptoverify.h"
+#include "pubkey.h"
+#include "random.h"
+
+#include <secp256k1.h>
+#include "ecwrapper.h"
+
+static secp256k1_context_t* secp256k1_context = NULL;
+
+bool CKey::Check(const unsigned char *vch) {
+    return eccrypto::Check(vch);
+}
+
+void CKey::MakeNewKey(bool fCompressedIn) {
+    RandAddSeedPerfmon();
+    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(secp256k1_context, (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(secp256k1_context, 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(secp256k1_context, (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);
+    int nSigLen = 72;
+    unsigned char extra_entropy[32] = {0};
+    WriteLE32(extra_entropy, test_case);
+    int ret = secp256k1_ecdsa_sign(secp256k1_context, hash.begin(), (unsigned char*)&vchSig[0], &nSigLen, begin(), secp256k1_nonce_function_rfc6979, test_case ? extra_entropy : NULL);
+    assert(ret);
+    vchSig.resize(nSigLen);
+    return 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(hash.begin());
+    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;
+    int ret = secp256k1_ecdsa_sign_compact(secp256k1_context, hash.begin(), &vchSig[1], begin(), secp256k1_nonce_function_rfc6979, NULL, &rec);
+    assert(ret);
+    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(secp256k1_context, (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, ChainCode &ccChild, unsigned int nChild, const ChainCode& cc) 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.begin(), out+32, 32);
+    memcpy((unsigned char*)keyChild.begin(), begin(), 32);
+    bool ret = secp256k1_ec_privkey_tweak_add(secp256k1_context, (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.chaincode, nChild, chaincode);
+}
+
+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(chaincode.begin(), &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();
+    ret.chaincode = chaincode;
+    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, chaincode.begin(), 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(chaincode.begin(), code+9, 32);
+    key.Set(code+42, code+74, true);
+}
+
+bool ECC_InitSanityCheck() {
+    if (!CECKey::SanityCheck()) {
+        return false;
+    }
+    CKey key;
+    key.MakeNewKey(true);
+    CPubKey pubkey = key.GetPubKey();
+    return key.VerifyPubKey(pubkey);
+}
+
+
+void ECC_Start() {
+    assert(secp256k1_context == NULL);
+
+    secp256k1_context_t *ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN);
+    assert(ctx != NULL);
+
+    {
+        // Pass in a random blinding seed to the secp256k1 context.
+        unsigned char seed[32];
+        LockObject(seed);
+        GetRandBytes(seed, 32);
+        bool ret = secp256k1_context_randomize(ctx, seed);
+        assert(ret);
+        UnlockObject(seed);
+    }
+
+    secp256k1_context = ctx;
+}
+
+void ECC_Stop() {
+    secp256k1_context_t *ctx = secp256k1_context;
+    secp256k1_context = NULL;
+
+    if (ctx) {
+        secp256k1_context_destroy(ctx);
+    }
+}