X-Git-Url: https://git.novaco.in/?p=novacoin.git;a=blobdiff_plain;f=src%2Fkey.cpp;h=c68fcda5fd748d1666560cd7eabffc97feb49a85;hp=400b1887c5c17576c3c72aad1ec619a3de895b79;hb=7218a68da35b3dddb228fd4647da831d249e6cd5;hpb=93db3fceac1bfe274bc0fd906428a20e709e2da5

diff --git a/src/key.cpp b/src/key.cpp
index 400b188..c68fcda 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -1,9 +1,15 @@
-// Copyright (c) 2011 The Bitcoin developers
+// Copyright (c) 2009-2012 The Bitcoin developers
 // Distributed under the MIT/X11 software license, see the accompanying
-// file license.txt or http://www.opensource.org/licenses/mit-license.php.
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <map>
 
-#include <openssl/ec.h>
 #include <openssl/ecdsa.h>
+#include <openssl/evp.h>
+#include <openssl/obj_mac.h>
+
+#include "key.h"
+#include "base58.h"
 
 // Generate a private key from just the secret parameter
 int EC_KEY_regenerate_key(EC_KEY *eckey, BIGNUM *priv_key)
@@ -44,7 +50,7 @@ err:
 
 // Perform ECDSA key recovery (see SEC1 4.1.6) for curves over (mod p)-fields
 // recid selects which key is recovered
-// if check is nonzero, additional checks are performed
+// if check is non-zero, additional checks are performed
 int ECDSA_SIG_recover_key_GFp(EC_KEY *eckey, ECDSA_SIG *ecsig, const unsigned char *msg, int msglen, int recid, int check)
 {
     if (!eckey) return 0;
@@ -115,3 +121,1137 @@ err:
     if (Q != NULL) EC_POINT_free(Q);
     return ret;
 }
+
+int CompareBigEndian(const unsigned char *c1, size_t c1len, const unsigned char *c2, size_t c2len) {
+    while (c1len > c2len) {
+        if (*c1)
+            return 1;
+        c1++;
+        c1len--;
+    }
+    while (c2len > c1len) {
+        if (*c2)
+            return -1;
+        c2++;
+        c2len--;
+    }
+    while (c1len > 0) {
+        if (*c1 > *c2)
+            return 1;
+        if (*c2 > *c1)
+            return -1;
+        c1++;
+        c2++;
+        c1len--;
+    }
+    return 0;
+}
+
+// Order of secp256k1's generator minus 1.
+const unsigned char vchMaxModOrder[32] = {
+    0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+    0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFE,
+    0xBA,0xAE,0xDC,0xE6,0xAF,0x48,0xA0,0x3B,
+    0xBF,0xD2,0x5E,0x8C,0xD0,0x36,0x41,0x40
+};
+
+// Half of the order of secp256k1's generator minus 1.
+const unsigned char vchMaxModHalfOrder[32] = {
+    0x7F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+    0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
+    0x5D,0x57,0x6E,0x73,0x57,0xA4,0x50,0x1D,
+    0xDF,0xE9,0x2F,0x46,0x68,0x1B,0x20,0xA0
+};
+
+const unsigned char *vchZero = NULL;
+
+void CKey::SetCompressedPubKey(bool fCompressed)
+{
+    EC_KEY_set_conv_form(pkey, fCompressed ? POINT_CONVERSION_COMPRESSED : POINT_CONVERSION_UNCOMPRESSED);
+}
+
+void CKey::Reset()
+{
+    fSet = false;
+    if (pkey != NULL)
+        EC_KEY_free(pkey);
+    pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    if (pkey == NULL)
+        throw key_error("CKey::CKey() : EC_KEY_new_by_curve_name failed");
+}
+
+CKey::CKey()
+{
+    pkey = NULL;
+    Reset();
+}
+
+CKey::CKey(const CKey& b)
+{
+    pkey = EC_KEY_dup(b.pkey);
+    if (pkey == NULL)
+        throw key_error("CKey::CKey(const CKey&) : EC_KEY_dup failed");
+    fSet = b.fSet;
+}
+
+CKey::CKey(const CSecret& b, bool fCompressed)
+{
+    pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    if (pkey == NULL)
+        throw key_error("CKey::CKey(const CKey&) : EC_KEY_dup failed");
+    SetSecret(b, fCompressed);
+}
+
+CKey& CKey::operator=(const CKey& b)
+{
+    if (!EC_KEY_copy(pkey, b.pkey))
+        throw key_error("CKey::operator=(const CKey&) : EC_KEY_copy failed");
+    fSet = b.fSet;
+    return (*this);
+}
+
+CKey::~CKey()
+{
+    if (pkey != NULL)
+        EC_KEY_free(pkey);
+}
+
+bool CKey::IsNull() const
+{
+    return !fSet;
+}
+
+bool CKey::IsCompressed() const
+{
+    return (EC_KEY_get_conv_form(pkey) == POINT_CONVERSION_COMPRESSED);
+}
+
+bool CKey::CheckSignatureElement(const unsigned char *vch, int len, bool half) {
+    return CompareBigEndian(vch, len, vchZero, 0) > 0 &&
+        CompareBigEndian(vch, len, half ? vchMaxModHalfOrder : vchMaxModOrder, 32) <= 0;
+}
+
+bool CPubKey::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))
+        throw key_error("CKey::MakeNewKey() : EC_KEY_generate_key failed");
+    SetCompressedPubKey(fCompressed);
+    fSet = true;
+}
+
+bool CKey::SetPrivKey(const CPrivKey& vchPrivKey)
+{
+    const unsigned char* pbegin = &vchPrivKey[0];
+    if (d2i_ECPrivateKey(&pkey, &pbegin, vchPrivKey.size()))
+    {
+        // In testing, d2i_ECPrivateKey can return true
+        // but fill in pkey with a key that fails
+        // EC_KEY_check_key, so:
+        if (EC_KEY_check_key(pkey))
+        {
+            fSet = true;
+            return true;
+        }
+    }
+    // If vchPrivKey data is bad d2i_ECPrivateKey() can
+    // leave pkey in a state where calling EC_KEY_free()
+    // crashes. To avoid that, set pkey to NULL and
+    // leak the memory (a leak is better than a crash)
+    pkey = NULL;
+    Reset();
+    return false;
+}
+
+bool CKey::SetSecret(const CSecret& vchSecret, bool fCompressed)
+{
+    EC_KEY_free(pkey);
+    pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    if (pkey == NULL)
+        throw key_error("CKey::SetSecret() : EC_KEY_new_by_curve_name failed");
+
+    if (vchSecret.size() != 32)
+        throw key_error("CKey::SetSecret() : secret must be 32 bytes");
+    BIGNUM *bn = BN_bin2bn(&vchSecret[0],32,BN_new());
+    if (bn == NULL)
+        throw key_error("CKey::SetSecret() : BN_bin2bn failed");
+    if (!EC_KEY_regenerate_key(pkey,bn))
+    {
+        BN_clear_free(bn);
+        throw key_error("CKey::SetSecret() : EC_KEY_regenerate_key failed");
+    }
+    BN_clear_free(bn);
+    fSet = true;
+    SetCompressedPubKey(fCompressed);
+    return true;
+}
+
+CSecret CKey::GetSecret(bool &fCompressed) const
+{
+    CSecret vchRet;
+    vchRet.resize(32);
+    const BIGNUM *bn = EC_KEY_get0_private_key(pkey);
+    int nBytes = BN_num_bytes(bn);
+    if (bn == NULL)
+        throw key_error("CKey::GetSecret() : EC_KEY_get0_private_key failed");
+    int n=BN_bn2bin(bn,&vchRet[32 - nBytes]);
+    if (n != nBytes)
+        throw key_error("CKey::GetSecret(): BN_bn2bin failed");
+    fCompressed = IsCompressed();
+    return vchRet;
+}
+
+bool CKey::WritePEM(BIO *streamObj, const SecureString &strPassKey) const // dumppem 4KJLA99FyqMMhjjDe7KnRXK4sjtv9cCtNS /tmp/test.pem 123
+{
+    EVP_PKEY *evpKey = EVP_PKEY_new();
+    if (!EVP_PKEY_assign_EC_KEY(evpKey, pkey))
+        return error("CKey::WritePEM() : Error initializing EVP_PKEY instance.");
+    if(!PEM_write_bio_PKCS8PrivateKey(streamObj, evpKey, EVP_aes_256_cbc(), (char *)&strPassKey[0], strPassKey.size(), NULL, NULL))
+        return error("CKey::WritePEM() : Error writing private key data to stream object");
+
+    return true;
+}
+
+CSecret CKey::GetSecret() const
+{
+    bool fCompressed;
+    return GetSecret(fCompressed);
+}
+
+CPrivKey CKey::GetPrivKey() const
+{
+    int nSize = i2d_ECPrivateKey(pkey, NULL);
+    if (!nSize)
+        throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey failed");
+    CPrivKey vchPrivKey(nSize, 0);
+    unsigned char* pbegin = &vchPrivKey[0];
+    if (i2d_ECPrivateKey(pkey, &pbegin) != nSize)
+        throw key_error("CKey::GetPrivKey() : i2d_ECPrivateKey returned unexpected size");
+    return vchPrivKey;
+}
+
+CPubKey CKey::GetPubKey() const
+{
+    int nSize = i2o_ECPublicKey(pkey, NULL);
+    if (!nSize)
+        throw key_error("CKey::GetPubKey() : i2o_ECPublicKey failed");
+    std::vector<unsigned char> vchPubKey(nSize, 0);
+    unsigned char* pbegin = &vchPubKey[0];
+    if (i2o_ECPublicKey(pkey, &pbegin) != nSize)
+        throw key_error("CKey::GetPubKey() : i2o_ECPublicKey returned unexpected size");
+    return CPubKey(vchPubKey);
+}
+
+bool CKey::Sign(uint256 hash, std::vector<unsigned char>& vchSig)
+{
+    vchSig.clear();
+    ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
+    if (sig==NULL)
+        return false;
+    const EC_GROUP *group = EC_KEY_get0_group(pkey);
+    CBigNum order, halforder;
+    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) > 0) {
+        BN_sub(sig->s, &order, sig->s);
+    }
+    unsigned int nSize = ECDSA_size(pkey);
+    vchSig.resize(nSize); // Make sure it is big enough
+    unsigned char *pos = &vchSig[0];
+    nSize = i2d_ECDSA_SIG(sig, &pos);
+    ECDSA_SIG_free(sig);
+    vchSig.resize(nSize); // Shrink to fit actual size
+    // Testing our new signature
+    if (ECDSA_verify(0, (unsigned char*)&hash, sizeof(hash), &vchSig[0], vchSig.size(), pkey) != 1) {
+        vchSig.clear();
+        return false;
+    }
+    return true;
+}
+
+// create a compact signature (65 bytes), which allows reconstructing the used public key
+// The format is one header byte, followed by two times 32 bytes for the serialized r and s values.
+// The header byte: 0x1B = first key with even y, 0x1C = first key with odd y,
+//                  0x1D = second key with even y, 0x1E = second key with odd y
+bool CKey::SignCompact(uint256 hash, std::vector<unsigned char>& vchSig)
+{
+    bool fOk = false;
+    ECDSA_SIG *sig = ECDSA_do_sign((unsigned char*)&hash, sizeof(hash), pkey);
+    if (sig==NULL)
+        return false;
+    const EC_GROUP *group = EC_KEY_get0_group(pkey);
+    CBigNum order, halforder;
+    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) > 0) {
+        BN_sub(sig->s, &order, sig->s);
+    }
+    vchSig.clear();
+    vchSig.resize(65,0);
+    int nBitsR = BN_num_bits(sig->r);
+    int nBitsS = BN_num_bits(sig->s);
+    bool fCompressedPubKey = IsCompressed();
+    if (nBitsR <= 256 && nBitsS <= 256)
+    {
+        int8_t nRecId = -1;
+        for (int8_t i=0; i<4; i++)
+        {
+            CKey keyRec;
+            keyRec.fSet = true;
+            keyRec.SetCompressedPubKey(fCompressedPubKey);
+            if (ECDSA_SIG_recover_key_GFp(keyRec.pkey, sig, (unsigned char*)&hash, sizeof(hash), i, 1) == 1)
+                if (keyRec.GetPubKey() == this->GetPubKey())
+                {
+                    nRecId = i;
+                    break;
+                }
+        }
+
+        if (nRecId == -1)
+        {
+            ECDSA_SIG_free(sig);
+            throw key_error("CKey::SignCompact() : unable to construct recoverable key");
+        }
+
+        vchSig[0] = nRecId+27+(fCompressedPubKey ? 4 : 0);
+        BN_bn2bin(sig->r,&vchSig[33-(nBitsR+7)/8]);
+        BN_bn2bin(sig->s,&vchSig[65-(nBitsS+7)/8]);
+        fOk = true;
+    }
+    ECDSA_SIG_free(sig);
+    return fOk;
+}
+
+// reconstruct public key from a compact signature
+// This is only slightly more CPU intensive than just verifying it.
+// If this function succeeds, the recovered public key is guaranteed to be valid
+// (the signature is a valid signature of the given data for that key)
+bool CPubKey::SetCompactSignature(uint256 hash, const std::vector<unsigned char>& vchSig)
+{
+    if (vchSig.size() != 65)
+        return false;
+    int nV = vchSig[0];
+    if (nV<27 || nV>=35)
+        return false;
+    ECDSA_SIG *sig = ECDSA_SIG_new();
+    BN_bin2bn(&vchSig[1],32,sig->r);
+    BN_bin2bn(&vchSig[33],32,sig->s);
+    bool fSuccessful = false;
+    EC_KEY* pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    if (nV >= 31)
+    {
+        nV -= 4;
+        EC_KEY_set_conv_form(pkey, POINT_CONVERSION_COMPRESSED);
+    }
+    do
+    {
+        if (ECDSA_SIG_recover_key_GFp(pkey, sig, (unsigned char*)&hash, sizeof(hash), nV - 27, 0) != 1)
+            break;
+        int nSize = i2o_ECPublicKey(pkey, NULL);
+        if (!nSize)
+            break;
+        std::vector<unsigned char> vchPubKey(nSize, 0);
+        unsigned char* pbegin = &vchPubKey[0];
+        if (i2o_ECPublicKey(pkey, &pbegin) != nSize)
+            break;
+        Set(vchPubKey.begin(), vchPubKey.end());
+        fSuccessful = IsValid();
+
+    } while (false);
+    ECDSA_SIG_free(sig);
+    EC_KEY_free(pkey);
+    if (!fSuccessful)
+        Invalidate();
+    return fSuccessful;
+}
+
+bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) const
+{
+    if (vchSig.empty() || !IsValid())
+        return false;
+
+    EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    ECDSA_SIG *norm_sig = ECDSA_SIG_new();
+
+    assert(norm_sig);
+    assert(pkey);
+
+    bool ret = false;
+    do
+    {
+        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);
+    EC_KEY_free(pkey);
+
+    return ret;
+}
+
+bool CPubKey::VerifyCompact(uint256 hash, const std::vector<unsigned char>& vchSig)
+{
+    CPubKey key;
+    if (!key.SetCompactSignature(hash, vchSig))
+        return false;
+    return true;
+}
+
+bool CKey::IsValid()
+{
+    if (!fSet)
+        return false;
+
+    if (!EC_KEY_check_key(pkey))
+        return false;
+
+    bool fCompr;
+    CSecret secret = GetSecret(fCompr);
+    CKey key2;
+    key2.SetSecret(secret, fCompr);
+
+    return GetPubKey() == key2.GetPubKey();
+}
+
+CPoint::CPoint()
+{
+    std::string err;
+    group = NULL;
+    point = NULL;
+    ctx   = NULL;
+
+    group = EC_GROUP_new_by_curve_name(NID_secp256k1);
+    if (!group) {
+        err = "EC_KEY_new_by_curve_name failed.";
+        goto finish;
+    }
+
+    point = EC_POINT_new(group);
+    if (!point) {
+        err = "EC_POINT_new failed.";
+        goto finish;
+    }
+
+    ctx = BN_CTX_new();
+    if (!ctx) {
+        err = "BN_CTX_new failed.";
+        goto finish;
+    }
+
+    return;
+
+finish:
+    if (group) EC_GROUP_free(group);
+    if (point) EC_POINT_free(point);
+    throw std::runtime_error(std::string("CPoint::CPoint() :  - ") + err);
+}
+
+bool CPoint::operator!=(const CPoint &a)
+{
+    if (EC_POINT_cmp(group, point, a.point, ctx) != 0)
+        return true;
+    return false;
+}
+CPoint::~CPoint()
+{
+    if (point) EC_POINT_free(point);
+    if (group) EC_GROUP_free(group);
+    if (ctx)   BN_CTX_free(ctx);
+}
+
+// Initialize from octets stream
+bool CPoint::setBytes(const std::vector<unsigned char> &vchBytes)
+{
+    if (!EC_POINT_oct2point(group, point, &vchBytes[0], vchBytes.size(), ctx)) {
+        return false;
+    }
+    return true;
+}
+
+// Initialize from octets stream
+bool CPoint::setPubKey(const CPubKey &key)
+{
+    std::vector<uint8_t> vchPubKey(key.begin(), key.end());
+    return setBytes(vchPubKey);
+}
+
+// Serialize to octets stream
+bool CPoint::getBytes(std::vector<unsigned char> &vchBytes)
+{
+    size_t nSize = EC_POINT_point2oct(group, point, POINT_CONVERSION_COMPRESSED, NULL, 0, ctx);
+    vchBytes.resize(nSize);
+    if (!(nSize == EC_POINT_point2oct(group, point, POINT_CONVERSION_COMPRESSED, &vchBytes[0], nSize, ctx))) {
+        return false;
+    }
+    return true;
+}
+
+// ECC multiplication by specified multiplier
+bool CPoint::ECMUL(const CBigNum &bnMultiplier)
+{
+    if (!EC_POINT_mul(group, point, NULL, point, &bnMultiplier, NULL)) {
+        printf("CPoint::ECMUL() : EC_POINT_mul failed");
+        return false;
+    }
+
+    return true;
+}
+
+// Calculate G*m + q
+bool CPoint::ECMULGEN(const CBigNum &bnMultiplier, const CPoint &qPoint)
+{
+    if (!EC_POINT_mul(group, point, &bnMultiplier, qPoint.point, BN_value_one(), NULL)) {
+        printf("CPoint::ECMULGEN() : EC_POINT_mul failed.");
+        return false;
+    }
+
+    return true;
+}
+
+// CMalleablePubKey
+
+void CMalleablePubKey::GetVariant(CPubKey &R, CPubKey &vchPubKeyVariant)
+{
+    EC_KEY *eckey = NULL;
+    eckey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    if (eckey == NULL) {
+        throw key_error("CMalleablePubKey::GetVariant() : EC_KEY_new_by_curve_name failed");
+    }
+
+    // Use standard key generation function to get r and R values.
+    //
+    // r will be presented by private key;
+    // R is ECDSA public key which calculated as G*r
+    if (!EC_KEY_generate_key(eckey)) {
+        throw key_error("CMalleablePubKey::GetVariant() : EC_KEY_generate_key failed");
+    }
+
+    EC_KEY_set_conv_form(eckey, POINT_CONVERSION_COMPRESSED);
+
+    int nSize = i2o_ECPublicKey(eckey, NULL);
+    if (!nSize) {
+        throw key_error("CMalleablePubKey::GetVariant() : i2o_ECPublicKey failed");
+    }
+
+    std::vector<unsigned char> vchPubKey(nSize, 0);
+    unsigned char* pbegin_R = &vchPubKey[0];
+
+    if (i2o_ECPublicKey(eckey, &pbegin_R) != nSize) {
+        throw key_error("CMalleablePubKey::GetVariant() : i2o_ECPublicKey returned unexpected size");
+    }
+
+    // R = G*r
+    R = CPubKey(vchPubKey);
+
+    // OpenSSL BIGNUM representation of r value
+    CBigNum bnr;
+    bnr = *(CBigNum*) EC_KEY_get0_private_key(eckey);
+    EC_KEY_free(eckey);
+
+    CPoint point;
+    if (!point.setPubKey(pubKeyL)) {
+        throw key_error("CMalleablePubKey::GetVariant() : Unable to decode L value");
+    }
+
+    // Calculate L*r
+    point.ECMUL(bnr);
+
+    std::vector<unsigned char> vchLr;
+    if (!point.getBytes(vchLr)) {
+        throw key_error("CMalleablePubKey::GetVariant() : Unable to convert Lr value");
+    }
+
+    // Calculate Hash(L*r) and then get a BIGNUM representation of hash value.
+    CBigNum bnHash;
+    bnHash.setuint160(Hash160(vchLr));
+
+    CPoint pointH;
+    pointH.setPubKey(pubKeyH);
+
+    CPoint P;
+    // Calculate P = Hash(L*r)*G + H
+    P.ECMULGEN(bnHash, pointH);
+
+    if (P.IsInfinity()) {
+        throw key_error("CMalleablePubKey::GetVariant() : P is infinity");
+    }
+
+    std::vector<unsigned char> vchResult;
+    P.getBytes(vchResult);
+
+    vchPubKeyVariant = CPubKey(vchResult);
+}
+
+std::string CMalleablePubKey::ToString() const
+{
+    CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
+    ssKey << *this;
+    std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
+
+    return EncodeBase58Check(vch);
+}
+
+bool CMalleablePubKey::setvch(const std::vector<unsigned char> &vchPubKeyPair)
+{
+    CDataStream ssKey(vchPubKeyPair, SER_NETWORK, PROTOCOL_VERSION);
+    ssKey >> *this;
+
+    return IsValid();
+}
+
+std::vector<unsigned char> CMalleablePubKey::Raw() const
+{
+    CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
+    ssKey << *this;
+    std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
+
+    return vch;
+}
+
+bool CMalleablePubKey::SetString(const std::string& strMalleablePubKey)
+{
+    std::vector<unsigned char> vchTemp;
+    if (!DecodeBase58Check(strMalleablePubKey, vchTemp)) {
+        throw key_error("CMalleablePubKey::SetString() : Provided key data seems corrupted.");
+    }
+    if (vchTemp.size() != 68)
+        return false;
+
+    CDataStream ssKey(vchTemp, SER_NETWORK, PROTOCOL_VERSION);
+    ssKey >> *this;
+
+    return IsValid();
+}
+
+bool CMalleablePubKey::operator==(const CMalleablePubKey &b)
+{
+    return pubKeyL == b.pubKeyL && pubKeyH == b.pubKeyH;
+}
+
+
+// CMalleableKey
+
+void CMalleableKey::Reset()
+{
+    vchSecretL.clear();
+    vchSecretH.clear();
+}
+
+void CMalleableKey::MakeNewKeys()
+{
+    Reset();
+
+    CKey keyL, keyH;
+    keyL.MakeNewKey();
+    keyH.MakeNewKey();
+
+    vchSecretL = keyL.GetSecret();
+    vchSecretH = keyH.GetSecret();
+}
+
+CMalleableKey::CMalleableKey()
+{
+    Reset();
+}
+
+CMalleableKey::CMalleableKey(const CMalleableKey &b)
+{
+    SetSecrets(b.vchSecretL, b.vchSecretH);
+}
+
+CMalleableKey::CMalleableKey(const CSecret &L, const CSecret &H)
+{
+    SetSecrets(L, H);
+}
+
+CMalleableKey::~CMalleableKey()
+{
+}
+
+bool CMalleableKey::IsNull() const
+{
+    return vchSecretL.size() != 32 || vchSecretH.size() != 32;
+}
+
+bool CMalleableKey::SetSecrets(const CSecret &pvchSecretL, const CSecret &pvchSecretH)
+{
+    Reset();
+
+    CKey keyL(pvchSecretL);
+    CKey keyH(pvchSecretH);
+
+    if (!keyL.IsValid() || !keyH.IsValid())
+        return false;
+
+    vchSecretL = pvchSecretL;
+    vchSecretH = pvchSecretH;
+
+    return true;
+}
+
+CMalleablePubKey CMalleableKey::GetMalleablePubKey() const
+{
+    CKey L(vchSecretL), H(vchSecretH);
+    return CMalleablePubKey(L.GetPubKey(), H.GetPubKey());
+}
+
+// Check ownership
+bool CMalleableKey::CheckKeyVariant(const CPubKey &R, const CPubKey &vchPubKeyVariant) const
+{
+    if (IsNull()) {
+        throw key_error("CMalleableKey::CheckKeyVariant() : Attempting to run on NULL key object.");
+    }
+
+    if (!R.IsValid()) {
+        printf("CMalleableKey::CheckKeyVariant() : R is invalid");
+        return false;
+    }
+
+    if (!vchPubKeyVariant.IsValid()) {
+        printf("CMalleableKey::CheckKeyVariant() : public key variant is invalid");
+        return false;
+    }
+
+    CPoint point_R;
+    if (!point_R.setPubKey(R)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to decode R value");
+        return false;
+    }
+
+    CKey H(vchSecretH);
+    CPubKey vchPubKeyH = H.GetPubKey();
+
+    CPoint point_H;
+    if (!point_H.setPubKey(vchPubKeyH)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to decode H value");
+        return false;
+    }
+
+    CPoint point_P;
+    if (!point_P.setPubKey(vchPubKeyVariant)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to decode P value");
+        return false;
+    }
+
+    // Infinity points are senseless
+    if (point_P.IsInfinity()) {
+        printf("CMalleableKey::CheckKeyVariant() : P is infinity");
+        return false;
+    }
+
+    CBigNum bnl;
+    bnl.setBytes(std::vector<unsigned char>(vchSecretL.begin(), vchSecretL.end()));
+
+    point_R.ECMUL(bnl);
+
+    std::vector<unsigned char> vchRl;
+    if (!point_R.getBytes(vchRl)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to convert Rl value");
+        return false;
+    }
+
+    // Calculate Hash(R*l)
+    CBigNum bnHash;
+    bnHash.setuint160(Hash160(vchRl));
+
+    CPoint point_Ps;
+    // Calculate Ps = Hash(L*r)*G + H
+    point_Ps.ECMULGEN(bnHash, point_H);
+
+    // Infinity points are senseless
+    if (point_Ps.IsInfinity()) {
+        printf("CMalleableKey::CheckKeyVariant() : Ps is infinity");
+        return false;
+    }
+
+    // Check ownership
+    if (point_Ps != point_P) {
+        return false;
+    }
+
+    return true;
+}
+
+// Check ownership and restore private key
+bool CMalleableKey::CheckKeyVariant(const CPubKey &R, const CPubKey &vchPubKeyVariant, CKey &privKeyVariant) const
+{
+    if (IsNull()) {
+        throw key_error("CMalleableKey::CheckKeyVariant() : Attempting to run on NULL key object.");
+    }
+
+    if (!R.IsValid()) {
+        printf("CMalleableKey::CheckKeyVariant() : R is invalid");
+        return false;
+    }
+
+    if (!vchPubKeyVariant.IsValid()) {
+        printf("CMalleableKey::CheckKeyVariant() : public key variant is invalid");
+        return false;
+    }
+
+    CPoint point_R;
+    if (!point_R.setPubKey(R)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to decode R value");
+        return false;
+    }
+
+    CKey H(vchSecretH);
+    CPubKey vchPubKeyH = H.GetPubKey();
+
+    CPoint point_H;
+    if (!point_H.setPubKey(vchPubKeyH)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to decode H value");
+        return false;
+    }
+
+    CPoint point_P;
+    if (!point_P.setPubKey(vchPubKeyVariant)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to decode P value");
+        return false;
+    }
+
+    // Infinity points are senseless
+    if (point_P.IsInfinity()) {
+        printf("CMalleableKey::CheckKeyVariant() : P is infinity");
+        return false;
+    }
+
+    CBigNum bnl;
+    bnl.setBytes(std::vector<unsigned char>(vchSecretL.begin(), vchSecretL.end()));
+
+    point_R.ECMUL(bnl);
+
+    std::vector<unsigned char> vchRl;
+    if (!point_R.getBytes(vchRl)) {
+        printf("CMalleableKey::CheckKeyVariant() : Unable to convert Rl value");
+        return false;
+    }
+
+    // Calculate Hash(R*l)
+    CBigNum bnHash;
+    bnHash.setuint160(Hash160(vchRl));
+
+    CPoint point_Ps;
+    // Calculate Ps = Hash(L*r)*G + H
+    point_Ps.ECMULGEN(bnHash, point_H);
+
+    // Infinity points are senseless
+    if (point_Ps.IsInfinity()) {
+        printf("CMalleableKey::CheckKeyVariant() : Ps is infinity");
+        return false;
+    }
+
+    // Check ownership
+    if (point_Ps != point_P) {
+        return false;
+    }
+
+    // OpenSSL BIGNUM representation of the second private key from (l, h) pair
+    CBigNum bnh;
+    bnh.setBytes(std::vector<unsigned char>(vchSecretH.begin(), vchSecretH.end()));
+
+    // Calculate p = Hash(R*l) + h
+    CBigNum bnp = bnHash + bnh;
+
+    std::vector<unsigned char> vchp = bnp.getBytes();
+    privKeyVariant.SetSecret(CSecret(vchp.begin(), vchp.end()));
+
+    return true;
+}
+
+std::string CMalleableKey::ToString() const
+{
+    CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
+    ssKey << *this;
+    std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
+
+    return EncodeBase58Check(vch);
+}
+
+std::vector<unsigned char> CMalleableKey::Raw() const
+{
+    CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
+    ssKey << *this;
+    std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
+
+    return vch;
+}
+
+bool CMalleableKey::SetString(const std::string& strMutableKey)
+{
+    std::vector<unsigned char> vchTemp;
+    if (!DecodeBase58Check(strMutableKey, vchTemp)) {
+        throw key_error("CMalleableKey::SetString() : Provided key data seems corrupted.");
+    }
+    if (vchTemp.size() != 66)
+        return false;
+    CDataStream ssKey(vchTemp, SER_NETWORK, PROTOCOL_VERSION);
+    ssKey >> *this;
+
+    return IsValid();
+}
+
+// CMalleableKeyView
+
+CMalleableKeyView::CMalleableKeyView(const std::string &strMalleableKey)
+{
+    SetString(strMalleableKey);
+}
+
+CMalleableKeyView::CMalleableKeyView(const CMalleableKey &b)
+{
+    if (b.vchSecretL.size() != 32)
+        throw key_error("CMalleableKeyView::CMalleableKeyView() : L size must be 32 bytes");
+
+    if (b.vchSecretH.size() != 32)
+        throw key_error("CMalleableKeyView::CMalleableKeyView() : H size must be 32 bytes");
+
+    vchSecretL = b.vchSecretL;
+
+    CKey H(b.vchSecretH);
+    vchPubKeyH = H.GetPubKey();
+}
+
+CMalleableKeyView::CMalleableKeyView(const CMalleableKeyView &b)
+{
+    vchSecretL = b.vchSecretL;
+    vchPubKeyH = b.vchPubKeyH;
+}
+
+CMalleableKeyView& CMalleableKeyView::operator=(const CMalleableKey &b)
+{
+    vchSecretL = b.vchSecretL;
+
+    CKey H(b.vchSecretH);
+    vchPubKeyH = H.GetPubKey();
+
+    return (*this);
+}
+
+CMalleableKeyView::~CMalleableKeyView()
+{
+}
+
+CMalleablePubKey CMalleableKeyView::GetMalleablePubKey() const
+{
+    CKey keyL(vchSecretL);
+    return CMalleablePubKey(keyL.GetPubKey(), vchPubKeyH);
+}
+
+// Check ownership
+bool CMalleableKeyView::CheckKeyVariant(const CPubKey &R, const CPubKey &vchPubKeyVariant) const
+{
+    if (!IsValid()) {
+        throw key_error("CMalleableKeyView::CheckKeyVariant() : Attempting to run on invalid view object.");
+    }
+
+    if (!R.IsValid()) {
+        printf("CMalleableKeyView::CheckKeyVariant() : R is invalid");
+        return false;
+    }
+
+    if (!vchPubKeyVariant.IsValid()) {
+        printf("CMalleableKeyView::CheckKeyVariant() : public key variant is invalid");
+        return false;
+    }
+
+    CPoint point_R;
+    if (!point_R.setPubKey(R)) {
+        printf("CMalleableKeyView::CheckKeyVariant() : Unable to decode R value");
+        return false;
+    }
+
+    CPoint point_H;
+    if (!point_H.setPubKey(vchPubKeyH)) {
+        printf("CMalleableKeyView::CheckKeyVariant() : Unable to decode H value");
+        return false;
+    }
+
+    CPoint point_P;
+    if (!point_P.setPubKey(vchPubKeyVariant)) {
+        printf("CMalleableKeyView::CheckKeyVariant() : Unable to decode P value");
+        return false;
+    }
+
+    // Infinity points are senseless
+    if (point_P.IsInfinity()) {
+        printf("CMalleableKeyView::CheckKeyVariant() : P is infinity");
+        return false;
+    }
+
+    CBigNum bnl;
+    bnl.setBytes(std::vector<unsigned char>(vchSecretL.begin(), vchSecretL.end()));
+
+    point_R.ECMUL(bnl);
+
+    std::vector<unsigned char> vchRl;
+    if (!point_R.getBytes(vchRl)) {
+        printf("CMalleableKeyView::CheckKeyVariant() : Unable to convert Rl value");
+        return false;
+    }
+
+    // Calculate Hash(R*l)
+    CBigNum bnHash;
+    bnHash.setuint160(Hash160(vchRl));
+
+    CPoint point_Ps;
+    // Calculate Ps = Hash(L*r)*G + H
+    point_Ps.ECMULGEN(bnHash, point_H);
+
+    // Infinity points are senseless
+    if (point_Ps.IsInfinity()) {
+        printf("CMalleableKeyView::CheckKeyVariant() : Ps is infinity");
+        return false;
+    }
+
+    // Check ownership
+    if (point_Ps != point_P) {
+        return false;
+    }
+
+    return true;
+}
+
+std::string CMalleableKeyView::ToString() const
+{
+    CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
+    ssKey << *this;
+    std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
+
+    return EncodeBase58Check(vch);
+}
+
+bool CMalleableKeyView::SetString(const std::string& strMutableKey)
+{
+    std::vector<unsigned char> vchTemp;
+    if (!DecodeBase58Check(strMutableKey, vchTemp)) {
+        throw key_error("CMalleableKeyView::SetString() : Provided key data seems corrupted.");
+    }
+
+    if (vchTemp.size() != 67)
+        return false;
+
+    CDataStream ssKey(vchTemp, SER_NETWORK, PROTOCOL_VERSION);
+    ssKey >> *this;
+
+    return IsValid();
+}
+
+std::vector<unsigned char> CMalleableKeyView::Raw() const
+{
+    CDataStream ssKey(SER_NETWORK, PROTOCOL_VERSION);
+    ssKey << *this;
+    std::vector<unsigned char> vch(ssKey.begin(), ssKey.end());
+
+    return vch;
+}
+
+
+bool CMalleableKeyView::IsValid() const
+{
+    return vchSecretL.size() == 32 && GetMalleablePubKey().IsValid();
+}
+
+//// Asymmetric encryption
+
+void CPubKey::EncryptData(const std::vector<unsigned char>& data, std::vector<unsigned char>& encrypted)
+{
+    ies_ctx_t *ctx;
+    char error[1024] = "Unknown error";
+    cryptogram_t *cryptogram;
+
+    const unsigned char* pbegin = &vbytes[0];
+    EC_KEY *pkey = EC_KEY_new_by_curve_name(NID_secp256k1);
+    if (!o2i_ECPublicKey(&pkey, &pbegin, size()))
+        throw key_error("Unable to parse EC key");
+
+    ctx = create_context(pkey);
+    if (!EC_KEY_get0_public_key(ctx->user_key))
+        throw key_error("Given EC key is not public key");
+
+    cryptogram = ecies_encrypt(ctx, (unsigned char*)&data[0], data.size(), error);
+    if (cryptogram == NULL) {
+        delete ctx;
+        ctx = NULL;
+        throw key_error(std::string("Error in encryption: %s") + error);
+    }
+
+    encrypted.resize(cryptogram_data_sum_length(cryptogram));
+    unsigned char *key_data = cryptogram_key_data(cryptogram);
+    memcpy(&encrypted[0], key_data, encrypted.size());
+    cryptogram_free(cryptogram);
+    delete ctx;
+}
+
+void CKey::DecryptData(const std::vector<unsigned char>& encrypted, std::vector<unsigned char>& data)
+{
+    ies_ctx_t *ctx;
+    char error[1024] = "Unknown error";
+    cryptogram_t *cryptogram;
+    size_t length;
+    unsigned char *decrypted;
+
+    ctx = create_context(pkey);
+    if (!EC_KEY_get0_private_key(ctx->user_key))
+        throw key_error("Given EC key is not private key");
+
+    size_t key_length = ctx->stored_key_length;
+    size_t mac_length = EVP_MD_size(ctx->md);
+    cryptogram = cryptogram_alloc(key_length, mac_length, encrypted.size() - key_length - mac_length);
+
+    memcpy(cryptogram_key_data(cryptogram), &encrypted[0], encrypted.size());
+
+    decrypted = ecies_decrypt(ctx, cryptogram, &length, error);
+    cryptogram_free(cryptogram);
+    delete ctx;
+
+    if (decrypted == NULL) {
+        throw key_error(std::string("Error in decryption: %s") + error);
+    }
+
+    data.resize(length);
+    memcpy(&data[0], decrypted, length);
+    free(decrypted);
+}