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
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
|
/*
* Adapted from hmac.c (HMAC-MD5) for use by SHA1.
* by <mcr@sandelman.ottawa.on.ca>. Test cases from RFC2202.
*
*/
/*
** Function: hmac_sha1
*/
RCSID("$Id$")
#ifdef HAVE_OPENSSL_EVP_H
#include <openssl/hmac.h>
#include <openssl/evp.h>
#include <freeradius-devel/openssl3.h>
#endif
#include <freeradius-devel/libradius.h>
#ifdef HMAC_SHA1_DATA_PROBLEMS
unsigned int sha1_data_problems = 0;
#endif
#ifdef HAVE_OPENSSL_EVP_H
/** Calculate HMAC using OpenSSL's SHA1 implementation
*
* @param digest Caller digest to be filled in.
* @param text Pointer to data stream.
* @param text_len length of data stream.
* @param key Pointer to authentication key.
* @param key_len Length of authentication key.
*/
void fr_hmac_sha1(uint8_t digest[SHA1_DIGEST_LENGTH], uint8_t const *text, size_t text_len,
uint8_t const *key, size_t key_len)
{
HMAC_CTX *ctx = HMAC_CTX_new();
unsigned int len = SHA1_DIGEST_LENGTH;
HMAC_Init_ex(ctx, key, key_len, EVP_sha1(), NULL);
HMAC_Update(ctx, text, text_len);
HMAC_Final(ctx, digest, &len);
HMAC_CTX_free(ctx);
}
#else
/** Calculate HMAC using internal SHA1 implementation
*
* @param digest Caller digest to be filled in.
* @param text Pointer to data stream.
* @param text_len length of data stream.
* @param key Pointer to authentication key.
* @param key_len Length of authentication key.
*/
void fr_hmac_sha1(uint8_t digest[SHA1_DIGEST_LENGTH], uint8_t const *text, size_t text_len,
uint8_t const *key, size_t key_len)
{
fr_sha1_ctx context;
uint8_t k_ipad[65]; /* inner padding - key XORd with ipad */
uint8_t k_opad[65]; /* outer padding - key XORd with opad */
uint8_t tk[20];
int i;
/* if key is longer than 64 bytes reset it to key=SHA1(key) */
if (key_len > 64) {
fr_sha1_ctx tctx;
fr_sha1_init(&tctx);
fr_sha1_update(&tctx, key, key_len);
fr_sha1_final(tk, &tctx);
key = tk;
key_len = 20;
}
#ifdef HMAC_SHA1_DATA_PROBLEMS
if(sha1_data_problems)
{
int j,k;
printf("\nhmac-sha1 key(%d): ", key_len);
j=0; k=0;
for (i = 0; i < key_len; i++) {
if(j==4) {
printf("_");
j=0;
}
j++;
printf("%02x", key[i]);
}
printf("\nDATA: (%d) ",text_len);
j=0; k=0;
for (i = 0; i < text_len; i++) {
if(k==20) {
printf("\n ");
k=0;
j=0;
}
if(j==4) {
printf("_");
j=0;
}
k++;
j++;
printf("%02x", text[i]);
}
printf("\n");
}
#endif
/*
* the HMAC_SHA1 transform looks like:
*
* SHA1(K XOR opad, SHA1(K XOR ipad, text))
*
* where K is an n byte key
* ipad is the byte 0x36 repeated 64 times
* opad is the byte 0x5c repeated 64 times
* and text is the data being protected
*/
/* start out by storing key in pads */
memset(k_ipad, 0, sizeof(k_ipad));
memset(k_opad, 0, sizeof(k_opad));
memcpy(k_ipad, key, key_len);
memcpy(k_opad, key, key_len);
/* XOR key with ipad and opad values */
for (i = 0; i < 64; i++) {
k_ipad[i] ^= 0x36;
k_opad[i] ^= 0x5c;
}
/*
* perform inner SHA1
*/
fr_sha1_init(&context); /* init context for 1st pass */
fr_sha1_update(&context, k_ipad, 64); /* start with inner pad */
fr_sha1_update(&context, text, text_len); /* then text of datagram */
fr_sha1_final(digest, &context); /* finish up 1st pass */
/*
* perform outer SHA1
*/
fr_sha1_init(&context); /* init context for 2nd pass */
fr_sha1_update(&context, k_opad, 64); /* start with outer pad */
fr_sha1_update(&context, digest, 20); /* then results of 1st hash */
fr_sha1_final(digest, &context); /* finish up 2nd pass */
#ifdef HMAC_SHA1_DATA_PROBLEMS
if (sha1_data_problems) {
int j;
printf("\nhmac-sha1 mac(20): ");
j=0;
for (i = 0; i < 20; i++) {
if(j==4) {
printf("_");
j=0;
}
j++;
printf("%02x", digest[i]);
}
printf("\n");
}
#endif
}
#endif /* HAVE_OPENSSL_EVP_H */
/*
Test Vectors (Trailing '\0' of a character string not included in test):
key = "Jefe"
data = "what do ya want for nothing?"
data_len = 28 bytes
digest = effcdf6ae5eb2fa2d27416d5f184df9c259a7c79
key = 0xAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
key_len 16 bytes
data = 0xDDDDDDDDDDDDDDDDDDDD...
..DDDDDDDDDDDDDDDDDDDD...
..DDDDDDDDDDDDDDDDDDDD...
..DDDDDDDDDDDDDDDDDDDD...
..DDDDDDDDDDDDDDDDDDDD
data_len = 50 bytes
digest = 0x56be34521d144c88dbb8c733f0e8b3f6
*/
#ifdef TESTING
/*
* cc -DTESTING -I ../include/ hmac.c sha1.c -o hmac
*
* ./hmac Jefe "what do ya want for nothing?"
*/
int main(int argc, char **argv)
{
uint8_t digest[20];
char *key;
int key_len;
char *text;
int text_len;
int i;
key = argv[1];
key_len = strlen(key);
text = argv[2];
text_len = strlen(text);
fr_hmac_sha1(digest, text, text_len, key, key_len);
for (i = 0; i < 20; i++) {
printf("%02x", digest[i]);
}
printf("\n");
exit(0);
return 0;
}
#endif
|
