byteblock encrypt_userdata(pool *p, const byteblock *plain)
{
byteblock stripped = strip_metas(p, plain);
byteblock prefixed = byteblock_concat(p, &prefix, &stripped);
byteblock total = byteblock_concat(p, &prefixed, &suffix);
byteblock padded = pkcs7_pad(p, &total, 16);
return rijndael_cbc_encrypt(p, &padded, &key, &iv);
}
size_t encrypt_AES_ECB(unsigned char *plaintext, unsigned char *ciphertext, size_t length, const unsigned char *key_str)
{
AES_KEY key;
AES_set_encrypt_key(key_str, 128, &key);
size_t new_length = pkcs7_pad(plaintext, length, 16);
int i;
for (i = 0; i < new_length; i += 16) {
AES_encrypt(&plaintext[i], &ciphertext[i], &key);
}
return new_length;
}
/*
* Perform an encrypt/decrypt operation to/from files using AES+CBC+PKCS7 pad.
* Set encrypt to 1 to encrypt, 0 to decrypt.
*
* Input: in/out files, key, iv, and mode
* Output: CRYPT_OK if no error
* Side Effects: bytes slurped from infile, pushed to outfile, fds updated.
*/
int do_crypt(FILE *infd, FILE *outfd, unsigned char *key, unsigned char *iv,
int encrypt)
{
union paddable inbuf, outbuf;
int cipher, ret;
symmetric_CBC cbc;
size_t nb;
/* Register your cipher! */
cipher = register_cipher(&aes_desc);
if(cipher == -1)
return CRYPT_INVALID_CIPHER;
/* Start a CBC session with cipher/key/val params */
ret = cbc_start(cipher, iv, key, KEY_LENGTH, 0, &cbc);
if( ret != CRYPT_OK )
return -1;
do {
/* Get bytes from the source */
nb = fread(inbuf.unpad, 1, sizeof(inbuf.unpad), infd);
if(!nb)
return encrypt ? CRYPT_OK : CRYPT_ERROR;
/* Barf if we got a read error */
if(ferror(infd))
return CRYPT_ERROR;
if(encrypt) {
/* We're encrypting, so pad first (if at EOF) and then
crypt */
if(feof(infd))
nb = pkcs7_pad(&inbuf, nb,
aes_desc.block_length, 1);
ret = cbc_encrypt(inbuf.pad, outbuf.pad, nb, &cbc);
if(ret != CRYPT_OK)
return ret;
} else {
/* We're decrypting, so decrypt and then unpad if at
EOF */
ret = cbc_decrypt(inbuf.unpad, outbuf.unpad, nb, &cbc);
if( ret != CRYPT_OK )
return ret;
if( feof(infd) )
nb = pkcs7_pad(&outbuf, nb,
aes_desc.block_length, 0);
if(nb == 0)
/* The file didn't decrypt correctly */
return CRYPT_ERROR;
}
/* Push bytes to outfile */
if(fwrite(outbuf.unpad, 1, nb, outfd) != nb)
return CRYPT_ERROR;
} while(!feof(infd));
/* Close up */
cbc_done(&cbc);
return CRYPT_OK;
}