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
162
163
164
165
166
167
|
/* See LICENSE file for copyright and license details. */
#include "common.h"
#ifndef TEST
#if defined(__GNUC__)
# pragma GCC diagnostic ignored "-Wformat-truncation=" /* we rely on snprintf(3) doing truncation */
#endif
ssize_t
librecrypt_add_algorithm(char *out_buffer, size_t size, char *augend, const char *restrict augment, void *reserved)
{
size_t prefix1, prefix2, min, ret, len, phraselen;
size_t hashsize1, hashsize2;
char *phrase, pad;
int strict_pad, r_int, nul_term;
const unsigned char *lut;
ssize_t r;
#define COPY_PREFIX()\
do {\
min = prefix1 < size ? prefix1 : size;\
if (out_buffer != augend)\
memmove(out_buffer, augend, min);\
out_buffer = &out_buffer[min];\
size -= min;\
} while (0)
/* Reserve space for NUL-termination */
if (size) {
nul_term = 1;
size -= 1u;
} else {
nul_term = 0;
}
/* Get the prefix and hash size in `augend` and `augment` */
prefix1 = librecrypt_settings_prefix(augend, &hashsize1);
prefix2 = librecrypt_settings_prefix(augment, &hashsize2);
/* If `augend` specifies as hash size rather than a hash, include it as the prefix */
if (augend[prefix1] == '*') {
prefix1 += strlen(&augend[prefix1]);
hashsize1 = 0u;
}
/* If `augend` doesn't contain a hash, we do not need to hash the hash,
* but we do need to include the final hash size if it is configurable */
if (!augend[prefix1]) {
if (augment[prefix2] == '*') {
prefix2 += strlen(&augment[prefix2]);
hashsize2 = 0u;
}
ret = prefix1 + 1u + prefix2;
if (size) {
COPY_PREFIX();
if (size) {
*out_buffer++ = LIBRECRYPT_ALGORITHM_LINK_DELIMITER;
size -= 1u;
}
min = prefix2 < size ? prefix2 : size;
memcpy(out_buffer, augment, min);
if (hashsize2) {
r_int = snprintf(&out_buffer[min], size + 1u, "*%zu", hashsize2);
if (r_int < 2)
abort();
ret += (size_t)r_int;
} else {
out_buffer[min] = '\0';
}
} else {
r_int = snprintf(NULL, 0, "*%zu", hashsize2);
if (r_int < 2)
abort();
ret += (size_t)r_int;
}
return (ssize_t)ret;
}
/* Measure size of hash size specification for `augend` */
if (hashsize1) {
r_int = snprintf(NULL, 0, "*%zu", hashsize1);
if (r_int < 2)
abort();
} else {
r_int = 0;
}
/* Measure `augent` and '>' in output */
ret = prefix1 + (size_t)r_int + 1u;
/* Decode the hash from base-64 to binary */
if (size <= ret + prefix2 + 1u) {
/* If the new hash doesn't fit, don't bother;
* hash sizes are independent of password size */
phrase = NULL;
phraselen = 0u;
} else {
/* Measure old ASCII hash; `strlen(augent)` will be `prefix1 + len` */
len = strlen(&augend[prefix1]);
/* Get encoding information */
lut = librecrypt_get_encoding(augend, prefix1 + len, &pad, &strict_pad, 1);
if (!lut)
return -1;
/* Measure old binary hash */
r = librecrypt_decode(NULL, 0, &augend[prefix1], len, lut, pad, strict_pad);
if (r <= 0) {
if (!r)
abort();
return -1;
}
phraselen = (size_t)r;
/* Decode old hash from ASCII to binary */
phrase = malloc(phraselen);
if (!phrase)
return -1;
if (librecrypt_decode(phrase, phraselen, &augend[prefix1], len, lut, pad, strict_pad) != r)
abort();
}
/* Chain the hash algorithms: write `augent` */
COPY_PREFIX();
if (hashsize1 && size)
if (snprintf(out_buffer, size + 1u, "*%zu", hashsize1) != r_int)
abort();
/* Chain the hash algorithms: write '>' */
if (size) {
*out_buffer++ = LIBRECRYPT_ALGORITHM_LINK_DELIMITER;
size -= 1u;
}
/* Chain the hash algorithms: write `augment` and hash */
r = librecrypt_crypt(out_buffer, size + (nul_term ? 1u : 0u), phrase, phraselen, augment, reserved);
if (r <= 0) {
librecrypt_wipe(phrase, phraselen);
free(phrase);
if (!r)
abort();
return -1;
}
ret += (size_t)r;
librecrypt_wipe(phrase, phraselen);
free(phrase);
return (ssize_t)ret;
}
#else
int
main(void)
{
SET_UP_ALARM();
return 0;
}
#endif
/* TODO test */
|
