49 lines
1.1 KiB
C
49 lines
1.1 KiB
C
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include "sm4_core.h"
|
|
|
|
static void rk_crypto_ofb128_encrypt(void *ctx, const unsigned char *in, unsigned char *out,
|
|
int len, unsigned char *ivec, unsigned int *num,block128_f block)
|
|
{
|
|
int n, l=0;
|
|
|
|
n = *num;
|
|
|
|
while (l<len) {
|
|
if (n==0) {
|
|
(*block)(ivec, ivec, ctx);
|
|
}
|
|
out[l] = in[l] ^ ivec[n];
|
|
++l;
|
|
n = (n+1) % SM4_BLOCK_SIZE;
|
|
}
|
|
|
|
*num=n;
|
|
}
|
|
|
|
/* XTS makes use of two different keys, usually generated by splitting
|
|
* the supplied block cipher's key in half.
|
|
* Because of the splitting, users wanting AES 256 and AES 128 encryption
|
|
* will need to choose key sizes of 512 bits and 256 bits respectively.
|
|
*/
|
|
int rk_sm4_ofb_encrypt(const unsigned char *in, unsigned char *out,
|
|
unsigned long length, const unsigned char *key, const int key_len,
|
|
unsigned char *ivec, const int enc)
|
|
{
|
|
sm4_context ctx;
|
|
unsigned int num = 0;
|
|
|
|
if(key_len != 16)
|
|
return -1;
|
|
|
|
if(length == 0)
|
|
return -1;
|
|
|
|
rk_sm4_setkey_enc(&ctx, key);
|
|
rk_crypto_ofb128_encrypt((void*)&ctx, in, out, length, ivec, &num, rk_rk_sm4_crypt_ecb);
|
|
return 0;
|
|
}
|
|
|
|
|