2025-05-10 21:58:58 +08:00

71 lines
1.5 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "aes_core.h"
typedef void (*block128_f)(const unsigned char in[16],
unsigned char out[16],
const void *key);
static void rk_crypto_cfb128_encrypt(const unsigned char *in, unsigned char *out,
size_t len, const void *key,
unsigned char ivec[16], int *num,
int enc, block128_f block)
{
unsigned int n;
size_t l = 0;
n = *num;
if (enc) {
while (l < len) {
if (n == 0) {
(*block)(ivec, ivec, key);
}
out[l] = ivec[n] ^= in[l];
++l;
n = (n+1) % 16;
}
*num = n;
} else {
while (l < len) {
unsigned char c;
if (n == 0) {
(*block)(ivec, ivec, key);
}
out[l] = ivec[n] ^ (c = in[l]); ivec[n] = c;
++l;
n = (n+1) % 16;
}
*num=n;
}
}
static void rk_aes_cfb128_encrypt(const unsigned char *in, unsigned char *out,
size_t length, const RK_AES_KEY *key,
unsigned char *ivec, int *num, const int enc)
{
rk_crypto_cfb128_encrypt(in,out,length,key,ivec,num,enc,(block128_f)rk_aes_encrypt);
}
int rk_aes_cfb_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)
{
RK_AES_KEY ks1;
int num = 0;
if (in == NULL || out ==NULL || key == NULL)
return -1;
if (key_len != 128 / 8 && key_len != 192 / 8 && key_len != 256 / 8)
return -2;
rk_aes_set_encrypt_key(key, key_len * 8, &ks1);
rk_aes_cfb128_encrypt(in, out, length, &ks1, ivec, &num, enc);
return 0;
}