1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis */
2 /* SPDX-License-Identifier: Unlicense */
3 #include "tomcrypt_private.h"
4
5 /**
6 @param md2.c
7 LTC_MD2 (RFC 1319) hash function implementation by Tom St Denis
8 */
9
10 #ifdef LTC_MD2
11
12 const struct ltc_hash_descriptor md2_desc =
13 {
14 "md2",
15 7,
16 16,
17 16,
18
19 /* OID */
20 { 1, 2, 840, 113549, 2, 2, },
21 6,
22
23 &md2_init,
24 &md2_process,
25 &md2_done,
26 &md2_test,
27 NULL
28 };
29
30 static const unsigned char PI_SUBST[256] = {
31 41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
32 19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
33 76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
34 138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
35 245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
36 148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
37 39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
38 181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
39 150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
40 112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
41 96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
42 85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
43 234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
44 129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
45 8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
46 203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
47 166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
48 31, 26, 219, 153, 141, 51, 159, 17, 131, 20
49 };
50
51 /* adds 16 bytes to the checksum */
s_md2_update_chksum(hash_state * md)52 static void s_md2_update_chksum(hash_state *md)
53 {
54 int j;
55 unsigned char L;
56 L = md->md2.chksum[15];
57 for (j = 0; j < 16; j++) {
58
59 /* caution, the RFC says its "C[j] = S[M[i*16+j] xor L]" but the reference source code [and test vectors] say
60 otherwise.
61 */
62 L = (md->md2.chksum[j] ^= PI_SUBST[(int)(md->md2.buf[j] ^ L)] & 255);
63 }
64 }
65
s_md2_compress(hash_state * md)66 static void s_md2_compress(hash_state *md)
67 {
68 int j, k;
69 unsigned char t;
70
71 /* copy block */
72 for (j = 0; j < 16; j++) {
73 md->md2.X[16+j] = md->md2.buf[j];
74 md->md2.X[32+j] = md->md2.X[j] ^ md->md2.X[16+j];
75 }
76
77 t = (unsigned char)0;
78
79 /* do 18 rounds */
80 for (j = 0; j < 18; j++) {
81 for (k = 0; k < 48; k++) {
82 t = (md->md2.X[k] ^= PI_SUBST[(int)(t & 255)]);
83 }
84 t = (t + (unsigned char)j) & 255;
85 }
86 }
87
88 /**
89 Initialize the hash state
90 @param md The hash state you wish to initialize
91 @return CRYPT_OK if successful
92 */
md2_init(hash_state * md)93 int md2_init(hash_state *md)
94 {
95 LTC_ARGCHK(md != NULL);
96
97 /* LTC_MD2 uses a zero'ed state... */
98 zeromem(md->md2.X, sizeof(md->md2.X));
99 zeromem(md->md2.chksum, sizeof(md->md2.chksum));
100 zeromem(md->md2.buf, sizeof(md->md2.buf));
101 md->md2.curlen = 0;
102 return CRYPT_OK;
103 }
104
105 /**
106 Process a block of memory though the hash
107 @param md The hash state
108 @param in The data to hash
109 @param inlen The length of the data (octets)
110 @return CRYPT_OK if successful
111 */
md2_process(hash_state * md,const unsigned char * in,unsigned long inlen)112 int md2_process(hash_state *md, const unsigned char *in, unsigned long inlen)
113 {
114 unsigned long n;
115 LTC_ARGCHK(md != NULL);
116 LTC_ARGCHK(in != NULL);
117 if (md-> md2 .curlen > sizeof(md-> md2 .buf)) {
118 return CRYPT_INVALID_ARG;
119 }
120 while (inlen > 0) {
121 n = MIN(inlen, (16 - md->md2.curlen));
122 XMEMCPY(md->md2.buf + md->md2.curlen, in, (size_t)n);
123 md->md2.curlen += n;
124 in += n;
125 inlen -= n;
126
127 /* is 16 bytes full? */
128 if (md->md2.curlen == 16) {
129 s_md2_compress(md);
130 s_md2_update_chksum(md);
131 md->md2.curlen = 0;
132 }
133 }
134 return CRYPT_OK;
135 }
136
137 /**
138 Terminate the hash to get the digest
139 @param md The hash state
140 @param out [out] The destination of the hash (16 bytes)
141 @return CRYPT_OK if successful
142 */
md2_done(hash_state * md,unsigned char * out)143 int md2_done(hash_state * md, unsigned char *out)
144 {
145 unsigned long i, k;
146
147 LTC_ARGCHK(md != NULL);
148 LTC_ARGCHK(out != NULL);
149
150 if (md->md2.curlen >= sizeof(md->md2.buf)) {
151 return CRYPT_INVALID_ARG;
152 }
153
154
155 /* pad the message */
156 k = 16 - md->md2.curlen;
157 for (i = md->md2.curlen; i < 16; i++) {
158 md->md2.buf[i] = (unsigned char)k;
159 }
160
161 /* hash and update */
162 s_md2_compress(md);
163 s_md2_update_chksum(md);
164
165 /* hash checksum */
166 XMEMCPY(md->md2.buf, md->md2.chksum, 16);
167 s_md2_compress(md);
168
169 /* output is lower 16 bytes of X */
170 XMEMCPY(out, md->md2.X, 16);
171
172 #ifdef LTC_CLEAN_STACK
173 zeromem(md, sizeof(hash_state));
174 #endif
175 return CRYPT_OK;
176 }
177
178 /**
179 Self-test the hash
180 @return CRYPT_OK if successful, CRYPT_NOP if self-tests have been disabled
181 */
md2_test(void)182 int md2_test(void)
183 {
184 #ifndef LTC_TEST
185 return CRYPT_NOP;
186 #else
187 static const struct {
188 const char *msg;
189 unsigned char hash[16];
190 } tests[] = {
191 { "",
192 {0x83,0x50,0xe5,0xa3,0xe2,0x4c,0x15,0x3d,
193 0xf2,0x27,0x5c,0x9f,0x80,0x69,0x27,0x73
194 }
195 },
196 { "a",
197 {0x32,0xec,0x01,0xec,0x4a,0x6d,0xac,0x72,
198 0xc0,0xab,0x96,0xfb,0x34,0xc0,0xb5,0xd1
199 }
200 },
201 { "message digest",
202 {0xab,0x4f,0x49,0x6b,0xfb,0x2a,0x53,0x0b,
203 0x21,0x9f,0xf3,0x30,0x31,0xfe,0x06,0xb0
204 }
205 },
206 { "abcdefghijklmnopqrstuvwxyz",
207 {0x4e,0x8d,0xdf,0xf3,0x65,0x02,0x92,0xab,
208 0x5a,0x41,0x08,0xc3,0xaa,0x47,0x94,0x0b
209 }
210 },
211 { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
212 {0xda,0x33,0xde,0xf2,0xa4,0x2d,0xf1,0x39,
213 0x75,0x35,0x28,0x46,0xc3,0x03,0x38,0xcd
214 }
215 },
216 { "12345678901234567890123456789012345678901234567890123456789012345678901234567890",
217 {0xd5,0x97,0x6f,0x79,0xd8,0x3d,0x3a,0x0d,
218 0xc9,0x80,0x6c,0x3c,0x66,0xf3,0xef,0xd8
219 }
220 }
221 };
222
223 int i;
224 unsigned char tmp[16];
225 hash_state md;
226
227 for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) {
228 md2_init(&md);
229 md2_process(&md, (unsigned char*)tests[i].msg, (unsigned long)XSTRLEN(tests[i].msg));
230 md2_done(&md, tmp);
231 if (compare_testvector(tmp, sizeof(tmp), tests[i].hash, sizeof(tests[i].hash), "MD2", i)) {
232 return CRYPT_FAIL_TESTVECTOR;
233 }
234 }
235 return CRYPT_OK;
236 #endif
237 }
238
239 #endif
240
241