git / moonbite-core / src/crypto/aes.cpp · raw

// Copyright (c) 2016-2019 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 <crypto/aes.h>#include <string.h>extern "C" {#include <crypto/ctaes/ctaes.c>}AES256Encrypt::AES256Encrypt(const unsigned char key[32]){    AES256_init(&ctx, key);}AES256Encrypt::~AES256Encrypt(){    memset(&ctx, 0, sizeof(ctx));}void AES256Encrypt::Encrypt(unsigned char ciphertext[16], const unsigned char plaintext[16]) const{    AES256_encrypt(&ctx, 1, ciphertext, plaintext);}AES256Decrypt::AES256Decrypt(const unsigned char key[32]){    AES256_init(&ctx, key);}AES256Decrypt::~AES256Decrypt(){    memset(&ctx, 0, sizeof(ctx));}void AES256Decrypt::Decrypt(unsigned char plaintext[16], const unsigned char ciphertext[16]) const{    AES256_decrypt(&ctx, 1, plaintext, ciphertext);}template <typename T>static int CBCEncrypt(const T& enc, const unsigned char iv[AES_BLOCKSIZE], const unsigned char* data, int size, bool pad, unsigned char* out){    int written = 0;    int padsize = size % AES_BLOCKSIZE;    unsigned char mixed[AES_BLOCKSIZE];    if (!data || !size || !out)        return 0;    if (!pad && padsize != 0)        return 0;    memcpy(mixed, iv, AES_BLOCKSIZE);    // Write all but the last block    while (written + AES_BLOCKSIZE <= size) {        for (int i = 0; i != AES_BLOCKSIZE; i++)            mixed[i] ^= *data++;        enc.Encrypt(out + written, mixed);        memcpy(mixed, out + written, AES_BLOCKSIZE);        written += AES_BLOCKSIZE;    }    if (pad) {        // For all that remains, pad each byte with the value of the remaining        // space. If there is none, pad by a full block.        for (int i = 0; i != padsize; i++)            mixed[i] ^= *data++;        for (int i = padsize; i != AES_BLOCKSIZE; i++)            mixed[i] ^= AES_BLOCKSIZE - padsize;        enc.Encrypt(out + written, mixed);        written += AES_BLOCKSIZE;    }    return written;}template <typename T>static int CBCDecrypt(const T& dec, const unsigned char iv[AES_BLOCKSIZE], const unsigned char* data, int size, bool pad, unsigned char* out){    int written = 0;    bool fail = false;    const unsigned char* prev = iv;    if (!data || !size || !out)        return 0;    if (size % AES_BLOCKSIZE != 0)        return 0;    // Decrypt all data. Padding will be checked in the output.    while (written != size) {        dec.Decrypt(out, data + written);        for (int i = 0; i != AES_BLOCKSIZE; i++)            *out++ ^= prev[i];        prev = data + written;        written += AES_BLOCKSIZE;    }    // When decrypting padding, attempt to run in constant-time    if (pad) {        // If used, padding size is the value of the last decrypted byte. For        // it to be valid, It must be between 1 and AES_BLOCKSIZE.        unsigned char padsize = *--out;        fail = !padsize | (padsize > AES_BLOCKSIZE);        // If not well-formed, treat it as though there's no padding.        padsize *= !fail;        // All padding must equal the last byte otherwise it's not well-formed        for (int i = AES_BLOCKSIZE; i != 0; i--)            fail |= ((i > AES_BLOCKSIZE - padsize) & (*out-- != padsize));        written -= padsize;    }    return written * !fail;}AES256CBCEncrypt::AES256CBCEncrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)    : enc(key), pad(padIn){    memcpy(iv, ivIn, AES_BLOCKSIZE);}int AES256CBCEncrypt::Encrypt(const unsigned char* data, int size, unsigned char* out) const{    return CBCEncrypt(enc, iv, data, size, pad, out);}AES256CBCEncrypt::~AES256CBCEncrypt(){    memset(iv, 0, sizeof(iv));}AES256CBCDecrypt::AES256CBCDecrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)    : dec(key), pad(padIn){    memcpy(iv, ivIn, AES_BLOCKSIZE);}int AES256CBCDecrypt::Decrypt(const unsigned char* data, int size, unsigned char* out) const{    return CBCDecrypt(dec, iv, data, size, pad, out);}AES256CBCDecrypt::~AES256CBCDecrypt(){    memset(iv, 0, sizeof(iv));}