xref: /OK3568_Linux_fs/external/security/librkcrypto/test/c_mode/sm4_cbc.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include "sm4_core.h"
5 
rk_crypto_cbc128_encrypt(void * ctx,const unsigned char * in,unsigned char * out,unsigned int len,unsigned char * ivec,block128_f block)6 static void rk_crypto_cbc128_encrypt(void *ctx, const unsigned char *in, unsigned char *out,
7 			unsigned int len, unsigned char *ivec, block128_f block)
8 {
9 	unsigned int n;
10 	const unsigned char *iv = ivec;
11 
12 	while (len) {
13 		for(n=0; n<SM4_BLOCK_SIZE && n<len; ++n)
14 			out[n] = in[n] ^ iv[n];
15 		for(; n<SM4_BLOCK_SIZE; ++n)
16 			out[n] = iv[n];
17 		(*block)(out, out, ctx);
18 		iv = out;
19 		if (len<=SM4_BLOCK_SIZE) break;
20 		len -= SM4_BLOCK_SIZE;
21 		in  += SM4_BLOCK_SIZE;
22 		out += SM4_BLOCK_SIZE;
23 	}
24 	memcpy(ivec,iv,SM4_BLOCK_SIZE);
25 }
26 
rk_crypto_cbc128_decrypt(void * ctx,const unsigned char * in,unsigned char * out,unsigned int len,unsigned char * ivec,block128_f block)27 static void rk_crypto_cbc128_decrypt(void *ctx, const unsigned char *in, unsigned char *out,
28 			unsigned int len, unsigned char *ivec, block128_f block)
29 {
30 	unsigned int n;
31 	unsigned char c;
32 	unsigned char tmp_buf[SM4_BLOCK_SIZE];
33 
34 	memset(tmp_buf, 0x00, sizeof(tmp_buf));
35 
36 	while (len) {
37 		(*block)(in, tmp_buf, ctx);
38 		for(n=0; n<SM4_BLOCK_SIZE && n<len; ++n) {
39 			c = in[n];
40 			out[n] = tmp_buf[n] ^ ivec[n];
41 			ivec[n] = c;
42 		}
43 		if (len<=SM4_BLOCK_SIZE) {
44 			for (; n<SM4_BLOCK_SIZE; ++n)
45 				ivec[n] = in[n];
46 			break;
47 		}
48 		len -= SM4_BLOCK_SIZE;
49 		in	+= SM4_BLOCK_SIZE;
50 		out += SM4_BLOCK_SIZE;
51 	}
52 
53 }
54 
rk_sm4_cbc_encrypt(const unsigned char * in,unsigned char * out,unsigned int length,const unsigned char * key,const int key_len,unsigned char * ivec,const int enc)55 int rk_sm4_cbc_encrypt(const unsigned char *in, unsigned char *out,
56         unsigned int length, const unsigned char *key, const int key_len,
57         unsigned char *ivec, const int enc)
58 {
59 		sm4_context  ctx;
60 
61 		if(key_len != 16)
62 			return -1;
63 
64 		if(length%SM4_BLOCK_SIZE || length == 0)
65 			return -1;
66 
67         if (enc) {
68 			rk_sm4_setkey_enc(&ctx, key);
69 			rk_crypto_cbc128_encrypt((void*)&ctx, in, out, length, ivec, rk_rk_sm4_crypt_ecb);
70         } else {
71 			rk_sm4_setkey_dec(&ctx, key);
72 			rk_crypto_cbc128_decrypt((void*)&ctx, in, out, length, ivec, rk_rk_sm4_crypt_ecb);
73         }
74 
75 
76 		return 0;
77 }
78 
79 
80