/*
* Append Operation for OctetStrings
*/
OctetString operator+(const OctetString& k1, const OctetString& k2)
{
secure_vector<uint8_t> out;
out += k1.bits_of();
out += k2.bits_of();
return OctetString(out);
}
/**
* A fully parametrized symmetric string encryption function
* Encrypts using the specified algorithm and CBC+PKCS7.
* Format as follows (//TODO ASN.1 Notation required):
* Base64
* {
* n bytes salt (parameter)
* 32 bytes IV
* message
* }
*/
string cryptTextUnauthenticated(string& plaintext, string& password, bool decrypt = false, string& algorithm = "Twofish", uint saltSize = 24)
{
AutoSeeded_RNG rng;
string fullAlgorithmName = algorithm + "/CBC/PKCS7";
//Generate a random salt
SecureVector<byte> salt(rng, saltSize);
//Check whether whe have to decrypt
Cipher_Dir direction = ENCRYPTION;
if(decrypt) {direction = DECRYPTION;}
SymmetricKey key = OctetString(hashRaw("SHA-256", password, salt));
InitializationVector iv(rng, 32);
Pipe encryptionPipe(new Chain(get_cipher(fullAlgorithmName, key, iv, direction)));
encryptionPipe.start_msg();
encryptionPipe.write(plaintext);
encryptionPipe.end_msg();
SecureVector<byte> encryptedData = encryptionPipe.read_all(0);
Pipe base64Pipe(new Base64_Encoder);
base64Pipe.start_msg ();
base64Pipe.write(salt);
base64Pipe.write(iv);
base64Pipe.write(encryptedData);
base64Pipe.end_msg();
return base64Pipe.read_all_as_string (0);
}
/*
* XOR Operation for OctetStrings
*/
OctetString operator^(const OctetString& k1, const OctetString& k2)
{
secure_vector<uint8_t> out(std::max(k1.length(), k2.length()));
copy_mem(out.data(), k1.begin(), k1.length());
xor_buf(out.data(), k2.begin(), k2.length());
return OctetString(out);
}
