1 // Copyright (c) 2009-2012 The Bitcoin Developers
2 // Distributed under the MIT/X11 software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 #include <openssl/aes.h>
6 #include <openssl/evp.h>
16 bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod)
18 if (nRounds < 1 || chSalt.size() != WALLET_CRYPTO_SALT_SIZE)
22 if (nDerivationMethod == 0)
24 i = EVP_BytesToKey(EVP_aes_256_cbc(), EVP_sha512(), &chSalt[0],
25 (unsigned char *)&strKeyData[0], strKeyData.size(), nRounds, chKey, chIV);
28 if (i != (int)WALLET_CRYPTO_KEY_SIZE)
30 OPENSSL_cleanse(&chKey, sizeof chKey);
31 OPENSSL_cleanse(&chIV, sizeof chIV);
39 bool CCrypter::SetKey(const CKeyingMaterial& chNewKey, const std::vector<unsigned char>& chNewIV)
41 if (chNewKey.size() != WALLET_CRYPTO_KEY_SIZE || chNewIV.size() != WALLET_CRYPTO_KEY_SIZE)
44 memcpy(&chKey[0], &chNewKey[0], sizeof chKey);
45 memcpy(&chIV[0], &chNewIV[0], sizeof chIV);
51 bool CCrypter::Encrypt(const CKeyingMaterial& vchPlaintext, std::vector<unsigned char> &vchCiphertext)
56 // max ciphertext len for a n bytes of plaintext is
57 // n + AES_BLOCK_SIZE - 1 bytes
58 int nLen = vchPlaintext.size();
59 int nCLen = nLen + AES_BLOCK_SIZE, nFLen = 0;
60 vchCiphertext = std::vector<unsigned char> (nCLen);
66 EVP_CIPHER_CTX_init(&ctx);
67 if (fOk) fOk = EVP_EncryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, chKey, chIV);
68 if (fOk) fOk = EVP_EncryptUpdate(&ctx, &vchCiphertext[0], &nCLen, &vchPlaintext[0], nLen);
69 if (fOk) fOk = EVP_EncryptFinal_ex(&ctx, (&vchCiphertext[0])+nCLen, &nFLen);
70 EVP_CIPHER_CTX_cleanup(&ctx);
72 if (!fOk) return false;
74 vchCiphertext.resize(nCLen + nFLen);
78 bool CCrypter::Decrypt(const std::vector<unsigned char>& vchCiphertext, CKeyingMaterial& vchPlaintext)
83 // plaintext will always be equal to or lesser than length of ciphertext
84 int nLen = vchCiphertext.size();
85 int nPLen = nLen, nFLen = 0;
87 vchPlaintext = CKeyingMaterial(nPLen);
93 EVP_CIPHER_CTX_init(&ctx);
94 if (fOk) fOk = EVP_DecryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, chKey, chIV);
95 if (fOk) fOk = EVP_DecryptUpdate(&ctx, &vchPlaintext[0], &nPLen, &vchCiphertext[0], nLen);
96 if (fOk) fOk = EVP_DecryptFinal_ex(&ctx, (&vchPlaintext[0])+nPLen, &nFLen);
97 EVP_CIPHER_CTX_cleanup(&ctx);
99 if (!fOk) return false;
101 vchPlaintext.resize(nPLen + nFLen);
106 bool EncryptSecret(CKeyingMaterial& vMasterKey, const CSecret &vchPlaintext, const uint256& nIV, std::vector<unsigned char> &vchCiphertext)
108 CCrypter cKeyCrypter;
109 std::vector<unsigned char> chIV(WALLET_CRYPTO_KEY_SIZE);
110 memcpy(&chIV[0], &nIV, WALLET_CRYPTO_KEY_SIZE);
111 if(!cKeyCrypter.SetKey(vMasterKey, chIV))
113 return cKeyCrypter.Encrypt((CKeyingMaterial)vchPlaintext, vchCiphertext);
116 bool DecryptSecret(const CKeyingMaterial& vMasterKey, const std::vector<unsigned char>& vchCiphertext, const uint256& nIV, CSecret& vchPlaintext)
118 CCrypter cKeyCrypter;
119 std::vector<unsigned char> chIV(WALLET_CRYPTO_KEY_SIZE);
120 memcpy(&chIV[0], &nIV, WALLET_CRYPTO_KEY_SIZE);
121 if(!cKeyCrypter.SetKey(vMasterKey, chIV))
123 return cKeyCrypter.Decrypt(vchCiphertext, *((CKeyingMaterial*)&vchPlaintext));