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comparison md2.c @ 3:7faae8f46238 libtomcrypt-orig

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Branch renaming
author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:25:41 +0000
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-1:000000000000 3:7faae8f46238
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
2 *
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
5 *
6 * The library is free for all purposes without any express
7 * guarantee it works.
8 *
9 * Tom St Denis, [email protected], http://libtomcrypt.org
10 */
11 /* MD2 (RFC 1319) hash function implementation by Tom St Denis */
12 #include "mycrypt.h"
13
14 #ifdef MD2
15
16 const struct _hash_descriptor md2_desc =
17 {
18 "md2",
19 7,
20 16,
21 16,
22 &md2_init,
23 &md2_process,
24 &md2_done,
25 &md2_test
26 };
27
28 static const unsigned char PI_SUBST[256] = {
29 41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
30 19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
31 76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
32 138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
33 245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
34 148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
35 39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
36 181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
37 150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
38 112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
39 96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
40 85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
41 234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
42 129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
43 8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
44 203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
45 166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
46 31, 26, 219, 153, 141, 51, 159, 17, 131, 20
47 };
48
49 /* adds 16 bytes to the checksum */
50 static void md2_update_chksum(hash_state *md)
51 {
52 int j;
53 unsigned char L;
54 L = md->md2.chksum[15];
55 for (j = 0; j < 16; j++) {
56
57 /* caution, the RFC says its "C[j] = S[M[i*16+j] xor L]" but the reference source code [and test vectors] say
58 otherwise.
59 */
60 L = (md->md2.chksum[j] ^= PI_SUBST[(int)(md->md2.buf[j] ^ L)] & 255);
61 }
62 }
63
64 static void md2_compress(hash_state *md)
65 {
66 int j, k;
67 unsigned char t;
68
69 /* copy block */
70 for (j = 0; j < 16; j++) {
71 md->md2.X[16+j] = md->md2.buf[j];
72 md->md2.X[32+j] = md->md2.X[j] ^ md->md2.X[16+j];
73 }
74
75 t = (unsigned char)0;
76
77 /* do 18 rounds */
78 for (j = 0; j < 18; j++) {
79 for (k = 0; k < 48; k++) {
80 t = (md->md2.X[k] ^= PI_SUBST[(int)(t & 255)]);
81 }
82 t = (t + (unsigned char)j) & 255;
83 }
84 }
85
86 void md2_init(hash_state *md)
87 {
88 _ARGCHK(md != NULL);
89
90 /* MD2 uses a zero'ed state... */
91 zeromem(md->md2.X, sizeof(md->md2.X));
92 zeromem(md->md2.chksum, sizeof(md->md2.chksum));
93 zeromem(md->md2.buf, sizeof(md->md2.buf));
94 md->md2.curlen = 0;
95 }
96
97 int md2_process(hash_state *md, const unsigned char *buf, unsigned long len)
98 {
99 unsigned long n;
100 _ARGCHK(md != NULL);
101 _ARGCHK(buf != NULL);
102 if (md-> md2 .curlen > sizeof(md-> md2 .buf)) {
103 return CRYPT_INVALID_ARG;
104 }
105 while (len > 0) {
106 n = MIN(len, (16 - md->md2.curlen));
107 memcpy(md->md2.buf + md->md2.curlen, buf, (size_t)n);
108 md->md2.curlen += n;
109 buf += n;
110 len -= n;
111
112 /* is 16 bytes full? */
113 if (md->md2.curlen == 16) {
114 md2_compress(md);
115 md2_update_chksum(md);
116 md->md2.curlen = 0;
117 }
118 }
119 return CRYPT_OK;
120 }
121
122 int md2_done(hash_state * md, unsigned char *hash)
123 {
124 unsigned long i, k;
125
126 _ARGCHK(md != NULL);
127 _ARGCHK(hash != NULL);
128
129 if (md->md2.curlen >= sizeof(md->md2.buf)) {
130 return CRYPT_INVALID_ARG;
131 }
132
133
134 /* pad the message */
135 k = 16 - md->md2.curlen;
136 for (i = md->md2.curlen; i < 16; i++) {
137 md->md2.buf[i] = (unsigned char)k;
138 }
139
140 /* hash and update */
141 md2_compress(md);
142 md2_update_chksum(md);
143
144 /* hash checksum */
145 memcpy(md->md2.buf, md->md2.chksum, 16);
146 md2_compress(md);
147
148 /* output is lower 16 bytes of X */
149 memcpy(hash, md->md2.X, 16);
150
151 #ifdef CLEAN_STACK
152 zeromem(md, sizeof(hash_state));
153 #endif
154 return CRYPT_OK;
155 }
156
157 int md2_test(void)
158 {
159 #ifndef LTC_TEST
160 return CRYPT_NOP;
161 #else
162 static const struct {
163 char *msg;
164 unsigned char md[16];
165 } tests[] = {
166 { "",
167 {0x83,0x50,0xe5,0xa3,0xe2,0x4c,0x15,0x3d,
168 0xf2,0x27,0x5c,0x9f,0x80,0x69,0x27,0x73
169 }
170 },
171 { "a",
172 {0x32,0xec,0x01,0xec,0x4a,0x6d,0xac,0x72,
173 0xc0,0xab,0x96,0xfb,0x34,0xc0,0xb5,0xd1
174 }
175 },
176 { "message digest",
177 {0xab,0x4f,0x49,0x6b,0xfb,0x2a,0x53,0x0b,
178 0x21,0x9f,0xf3,0x30,0x31,0xfe,0x06,0xb0
179 }
180 },
181 { "abcdefghijklmnopqrstuvwxyz",
182 {0x4e,0x8d,0xdf,0xf3,0x65,0x02,0x92,0xab,
183 0x5a,0x41,0x08,0xc3,0xaa,0x47,0x94,0x0b
184 }
185 },
186 { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
187 {0xda,0x33,0xde,0xf2,0xa4,0x2d,0xf1,0x39,
188 0x75,0x35,0x28,0x46,0xc3,0x03,0x38,0xcd
189 }
190 },
191 { "12345678901234567890123456789012345678901234567890123456789012345678901234567890",
192 {0xd5,0x97,0x6f,0x79,0xd8,0x3d,0x3a,0x0d,
193 0xc9,0x80,0x6c,0x3c,0x66,0xf3,0xef,0xd8
194 }
195 }
196 };
197 int i;
198 hash_state md;
199 unsigned char buf[16];
200
201 for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) {
202 md2_init(&md);
203 md2_process(&md, (unsigned char*)tests[i].msg, (unsigned long)strlen(tests[i].msg));
204 md2_done(&md, buf);
205 if (memcmp(buf, tests[i].md, 16) != 0) {
206 return CRYPT_FAIL_TESTVECTOR;
207 }
208 }
209 return CRYPT_OK;
210 #endif
211 }
212
213 #endif
214