1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
/*
* Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <openssl/crypto.h>
#include "modes_lcl.h"
#include <string.h>
#if !defined(STRICT_ALIGNMENT) && !defined(PEDANTIC)
# define STRICT_ALIGNMENT 0
#endif
void CRYPTO_cbc128_encrypt(const unsigned char *in, unsigned char *out,
size_t len, const void *key,
unsigned char ivec[16], block128_f block)
{
size_t n;
const unsigned char *iv = ivec;
if (len == 0)
return;
#if !defined(OPENSSL_SMALL_FOOTPRINT)
if (STRICT_ALIGNMENT &&
((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) {
while (len >= 16) {
for (n = 0; n < 16; ++n)
out[n] = in[n] ^ iv[n];
(*block) (out, out, key);
iv = out;
len -= 16;
in += 16;
out += 16;
}
} else {
while (len >= 16) {
for (n = 0; n < 16; n += sizeof(size_t))
*(size_t *)(out + n) =
*(size_t *)(in + n) ^ *(size_t *)(iv + n);
(*block) (out, out, key);
iv = out;
len -= 16;
in += 16;
out += 16;
}
}
#endif
while (len) {
for (n = 0; n < 16 && n < len; ++n)
out[n] = in[n] ^ iv[n];
for (; n < 16; ++n)
out[n] = iv[n];
(*block) (out, out, key);
iv = out;
if (len <= 16)
break;
len -= 16;
in += 16;
out += 16;
}
memcpy(ivec, iv, 16);
}
void CRYPTO_cbc128_decrypt(const unsigned char *in, unsigned char *out,
size_t len, const void *key,
unsigned char ivec[16], block128_f block)
{
size_t n;
union {
size_t t[16 / sizeof(size_t)];
unsigned char c[16];
} tmp;
if (len == 0)
return;
#if !defined(OPENSSL_SMALL_FOOTPRINT)
if (in != out) {
const unsigned char *iv = ivec;
if (STRICT_ALIGNMENT &&
((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) {
while (len >= 16) {
(*block) (in, out, key);
for (n = 0; n < 16; ++n)
out[n] ^= iv[n];
iv = in;
len -= 16;
in += 16;
out += 16;
}
} else if (16 % sizeof(size_t) == 0) { /* always true */
while (len >= 16) {
size_t *out_t = (size_t *)out, *iv_t = (size_t *)iv;
(*block) (in, out, key);
for (n = 0; n < 16 / sizeof(size_t); n++)
out_t[n] ^= iv_t[n];
iv = in;
len -= 16;
in += 16;
out += 16;
}
}
memcpy(ivec, iv, 16);
} else {
if (STRICT_ALIGNMENT &&
((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) {
unsigned char c;
while (len >= 16) {
(*block) (in, tmp.c, key);
for (n = 0; n < 16; ++n) {
c = in[n];
out[n] = tmp.c[n] ^ ivec[n];
ivec[n] = c;
}
len -= 16;
in += 16;
out += 16;
}
} else if (16 % sizeof(size_t) == 0) { /* always true */
while (len >= 16) {
size_t c, *out_t = (size_t *)out, *ivec_t = (size_t *)ivec;
const size_t *in_t = (const size_t *)in;
(*block) (in, tmp.c, key);
for (n = 0; n < 16 / sizeof(size_t); n++) {
c = in_t[n];
out_t[n] = tmp.t[n] ^ ivec_t[n];
ivec_t[n] = c;
}
len -= 16;
in += 16;
out += 16;
}
}
}
#endif
while (len) {
unsigned char c;
(*block) (in, tmp.c, key);
for (n = 0; n < 16 && n < len; ++n) {
c = in[n];
out[n] = tmp.c[n] ^ ivec[n];
ivec[n] = c;
}
if (len <= 16) {
for (; n < 16; ++n)
ivec[n] = in[n];
break;
}
len -= 16;
in += 16;
out += 16;
}
}
|