1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <assert.h>
5 #include "aes_core.h"
6
rk_crypto_cbc128_encrypt(const unsigned char * in,unsigned char * out,int len,const void * key,unsigned char * ivec)7 static void rk_crypto_cbc128_encrypt(const unsigned char *in, unsigned char *out,
8 int len, const void *key, unsigned char *ivec)
9 {
10 int n;
11 const unsigned char *iv = ivec;
12
13 while (len) {
14 for(n=0; n<AES_BLOCK_SIZE && n<len; ++n)
15 out[n] = in[n] ^ iv[n];
16 for(; n<AES_BLOCK_SIZE; ++n)
17 out[n] = iv[n];
18 rk_aes_encrypt(out, out,key);
19 iv = out;
20 if (len<=AES_BLOCK_SIZE) break;
21 len -= AES_BLOCK_SIZE;
22 in += AES_BLOCK_SIZE;
23 out += AES_BLOCK_SIZE;
24 }
25 memcpy(ivec,iv,AES_BLOCK_SIZE);
26 }
27
rk_crypto_cbc128_decrypt(const unsigned char * in,unsigned char * out,int len,const void * key,unsigned char * ivec)28 static void rk_crypto_cbc128_decrypt(const unsigned char *in, unsigned char *out,
29 int len, const void *key, unsigned char *ivec)
30 {
31 int n;
32 unsigned char c;
33 unsigned char tmp_buf[AES_BLOCK_SIZE];
34
35 memset(tmp_buf, 0x00, sizeof(tmp_buf));
36
37 while (len) {
38 rk_aes_decrypt(in, tmp_buf, key);
39 for(n=0; n<AES_BLOCK_SIZE && n<len; ++n) {
40 c = in[n];
41 out[n] = tmp_buf[n] ^ ivec[n];
42 ivec[n] = c;
43 }
44 if (len<=AES_BLOCK_SIZE) {
45 for (; n<AES_BLOCK_SIZE; ++n)
46 ivec[n] = in[n];
47 break;
48 }
49 len -= AES_BLOCK_SIZE;
50 in += AES_BLOCK_SIZE;
51 out += AES_BLOCK_SIZE;
52 }
53 }
54
55
rk_crypto_cts_encrypt(const unsigned char * in,unsigned char * out,unsigned long length,const RK_AES_KEY * ks1,unsigned char * ivec,const int enc)56 static int rk_crypto_cts_encrypt(const unsigned char *in, unsigned char *out,
57 unsigned long length, const RK_AES_KEY *ks1, unsigned char *ivec, const int enc)
58 {
59 int k = 0, r = 0;
60
61 r = length % AES_BLOCK_SIZE;
62 if (r) {
63 k = length - r - AES_BLOCK_SIZE;
64 } else {
65 k = length;
66 }
67
68 if (enc){
69 unsigned char peniv[AES_BLOCK_SIZE] = {0};
70 memset(peniv, 0x00, sizeof(peniv));
71
72 rk_crypto_cbc128_encrypt(in, out, k, ks1, ivec);
73
74 if (r) {
75 memcpy(peniv, in + k + AES_BLOCK_SIZE, r);
76
77 rk_crypto_cbc128_encrypt(in + k, out + k, AES_BLOCK_SIZE, ks1, ivec);
78 memcpy(out + length - r, out + k, r);
79 rk_crypto_cbc128_encrypt(peniv, out + k, AES_BLOCK_SIZE, ks1, ivec);
80 }else{
81 //swap last two block
82 memcpy(peniv, out + length - AES_BLOCK_SIZE, AES_BLOCK_SIZE);
83 memcpy(out + length - AES_BLOCK_SIZE, out + length - 2*AES_BLOCK_SIZE, AES_BLOCK_SIZE);
84 memcpy(out + length - 2*AES_BLOCK_SIZE, peniv, AES_BLOCK_SIZE);
85 }
86 }else{
87 int i;
88 unsigned char *pout_tmp = NULL;
89 unsigned char tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
90
91 memset(tmp1, 0x00, sizeof(tmp1));
92 memset(tmp2, 0x00, sizeof(tmp2));
93
94 if(r == 0){
95 rk_crypto_cbc128_decrypt(in, out, k-2*AES_BLOCK_SIZE, ks1, ivec);
96 //swap last two block
97 rk_crypto_cbc128_decrypt(in + length - AES_BLOCK_SIZE, out + length - 2*AES_BLOCK_SIZE,
98 AES_BLOCK_SIZE, ks1, ivec);
99 rk_crypto_cbc128_decrypt(in + length - 2*AES_BLOCK_SIZE, out + length - AES_BLOCK_SIZE,
100 AES_BLOCK_SIZE, ks1, ivec);
101 }else{
102 rk_crypto_cbc128_decrypt(in, out, k, ks1, ivec);
103 rk_aes_decrypt(in + k, tmp1, ks1);
104
105 memcpy(tmp2, in + k + AES_BLOCK_SIZE, r);
106 memcpy(tmp2+r, tmp1+r, AES_BLOCK_SIZE-r);
107
108 //get last one plain text
109 pout_tmp = out + k + AES_BLOCK_SIZE;
110 for(i=0; i<AES_BLOCK_SIZE; i++,pout_tmp++)
111 *pout_tmp = tmp1[i] ^ tmp2[i];
112
113 rk_aes_decrypt(tmp2, tmp2, ks1);
114
115 //get sencond to last plain text
116 pout_tmp = out + k;
117 for(i=0; i<AES_BLOCK_SIZE; i++,pout_tmp++)
118 *pout_tmp = tmp2[i] ^ ivec[i];
119 }
120 }
121
122 return 0;
123 }
124
125
rk_aes_cts_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)126 int rk_aes_cts_encrypt(const unsigned char *in, unsigned char *out,
127 unsigned long length, const unsigned char *key, const int key_len,
128 unsigned char *ivec, const int enc)
129 {
130 RK_AES_KEY ks1;
131
132 if (in == NULL || out ==NULL || key == NULL)
133 return -1;
134
135 if (key_len != 128/8 && key_len != 192/8 && key_len != 256/8)
136 return -2;
137
138 if(length <= AES_BLOCK_SIZE)
139 return -3;
140
141 if (enc) {
142 rk_aes_set_encrypt_key(key, key_len * 8, &ks1);
143 } else {
144 rk_aes_set_decrypt_key(key, key_len * 8, &ks1);
145 }
146
147 rk_crypto_cts_encrypt(in, out, length, &ks1, ivec, enc);
148
149 return 0;
150 }
151
152
153