Repository navigation
Expand file tree
/
Copy pathpwd2key.c
More file actions
181 lines (154 loc) · 5.39 KB
/
Copy pathpwd2key.c
File metadata and controls
181 lines (154 loc) · 5.39 KB
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
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/*
---------------------------------------------------------------------------
Copyright (c) 1998-2010, Brian Gladman, Worcester, UK. All rights reserved.
The redistribution and use of this software (with or without changes)
is allowed without the payment of fees or royalties provided that:
source code distributions include the above copyright notice, this
list of conditions and the following disclaimer;
binary distributions include the above copyright notice, this list
of conditions and the following disclaimer in their documentation.
This software is provided 'as is' with no explicit or implied warranties
in respect of its operation, including, but not limited to, correctness
and fitness for purpose.
---------------------------------------------------------------------------
Issue Date: 20/12/2007
This is an implementation of RFC2898, which specifies key derivation from
a password and a salt value.
*/
#include <string.h>
#include "hmac.h"
#if defined(__cplusplus)
extern "C"
{
#endif
void derive_key(const unsigned char pwd[], /* the PASSWORD */
unsigned int pwd_len, /* and its length */
const unsigned char salt[], /* the SALT and its */
unsigned int salt_len, /* length */
unsigned int iter, /* the number of iterations */
unsigned char key[], /* space for the output key */
unsigned int key_len)/* and its required length */
{
unsigned int i, j, k, n_blk, h_size;
unsigned char uu[HMAC_MAX_OUTPUT_SIZE], ux[HMAC_MAX_OUTPUT_SIZE];
hmac_ctx c1[1], c2[1], c3[1];
/* set HMAC context (c1) for password */
h_size = hmac_sha_begin(HMAC_SHA1, c1);
hmac_sha_key(pwd, pwd_len, c1);
/* set HMAC context (c2) for password and salt */
memcpy(c2, c1, sizeof(hmac_ctx));
hmac_sha_data(salt, salt_len, c2);
/* find the number of SHA blocks in the key */
n_blk = 1 + (key_len - 1) / h_size;
for(i = 0; i < n_blk; ++i) /* for each block in key */
{
/* ux[] holds the running xor value */
memset(ux, 0, h_size);
/* set HMAC context (c3) for password and salt */
memcpy(c3, c2, sizeof(hmac_ctx));
/* enter additional data for 1st block into uu */
uu[0] = (unsigned char)((i + 1) >> 24);
uu[1] = (unsigned char)((i + 1) >> 16);
uu[2] = (unsigned char)((i + 1) >> 8);
uu[3] = (unsigned char)(i + 1);
/* this is the key mixing iteration */
for(j = 0, k = 4; j < iter; ++j)
{
/* add previous round data to HMAC */
hmac_sha_data(uu, k, c3);
/* obtain HMAC for uu[] */
hmac_sha_end(uu, h_size, c3);
/* xor into the running xor block */
for(k = 0; k < h_size; ++k)
ux[k] ^= uu[k];
/* set HMAC context (c3) for password */
memcpy(c3, c1, sizeof(hmac_ctx));
}
/* compile key blocks into the key output */
j = 0; k = i * h_size;
while(j < h_size && k < key_len)
key[k++] = ux[j++];
}
}
#ifdef TEST
#include <stdio.h>
struct
{ unsigned int pwd_len;
unsigned int salt_len;
unsigned int it_count;
unsigned char *pwd;
unsigned char salt[32];
unsigned char key[32];
} tests[] =
{
{ 8, 4, 5, (unsigned char*)"password",
{
0x12, 0x34, 0x56, 0x78
},
{
0x5c, 0x75, 0xce, 0xf0, 0x1a, 0x96, 0x0d, 0xf7,
0x4c, 0xb6, 0xb4, 0x9b, 0x9e, 0x38, 0xe6, 0xb5
}
},
{ 8, 8, 5, (unsigned char*)"password",
{
0x12, 0x34, 0x56, 0x78, 0x78, 0x56, 0x34, 0x12
},
{
0xd1, 0xda, 0xa7, 0x86, 0x15, 0xf2, 0x87, 0xe6,
0xa1, 0xc8, 0xb1, 0x20, 0xd7, 0x06, 0x2a, 0x49
}
},
{ 8, 21, 1, (unsigned char*)"password",
{
"ATHENA.MIT.EDUraeburn"
},
{
0xcd, 0xed, 0xb5, 0x28, 0x1b, 0xb2, 0xf8, 0x01,
0x56, 0x5a, 0x11, 0x22, 0xb2, 0x56, 0x35, 0x15
}
},
{ 8, 21, 2, (unsigned char*)"password",
{
"ATHENA.MIT.EDUraeburn"
},
{
0x01, 0xdb, 0xee, 0x7f, 0x4a, 0x9e, 0x24, 0x3e,
0x98, 0x8b, 0x62, 0xc7, 0x3c, 0xda, 0x93, 0x5d
}
},
{ 8, 21, 1200, (unsigned char*)"password",
{
"ATHENA.MIT.EDUraeburn"
},
{
0x5c, 0x08, 0xeb, 0x61, 0xfd, 0xf7, 0x1e, 0x4e,
0x4e, 0xc3, 0xcf, 0x6b, 0xa1, 0xf5, 0x51, 0x2b
}
}
};
int main()
{ unsigned int i, j, key_len = 256;
unsigned char key[256];
printf("\nTest of RFC2898 Password Based Key Derivation");
for(i = 0; i < 5; ++i)
{
derive_key(tests[i].pwd, tests[i].pwd_len, tests[i].salt,
tests[i].salt_len, tests[i].it_count, key, key_len);
printf("\ntest %i: ", i + 1);
printf("key %s", memcmp(tests[i].key, key, 16) ? "is bad" : "is good");
for(j = 0; j < key_len && j < 64; j += 4)
{
if(j % 16 == 0)
printf("\n");
printf("0x%02x%02x%02x%02x ", key[j], key[j + 1], key[j + 2], key[j + 3]);
}
printf(j < key_len ? " ... \n" : "\n");
}
printf("\n");
return 0;
}
#if defined(__cplusplus)
}
#endif
#endif