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, tomstdenis (at) gmail.com, http://libtomcrypt.com 10 */ 11 #include "tomcrypt.h" 12 13 /** 14 @param md2.c 15 MD2 (RFC 1319) hash function implementation by Tom St Denis 16 */ 17 18 #ifdef MD2 19 20 const struct ltc_hash_descriptor md2_desc = 21 { 22 "md2", 23 7, 24 16, 25 16, 26 27 /* OID */ 28 { 1, 2, 840, 113549, 2, 2, }, 29 6, 30 31 &md2_init, 32 &md2_process, 33 &md2_done, 34 &md2_test, 35 NULL 36 }; 37 38 static const unsigned char PI_SUBST[256] = { 39 41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6, 40 19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188, 41 76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24, 42 138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251, 43 245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63, 44 148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50, 45 39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165, 46 181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210, 47 150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157, 48 112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27, 49 96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15, 50 85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197, 51 234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65, 52 129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123, 53 8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233, 54 203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228, 55 166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237, 56 31, 26, 219, 153, 141, 51, 159, 17, 131, 20 57 }; 58 59 /* adds 16 bytes to the checksum */ 60 static void md2_update_chksum(hash_state *md) 61 { 62 int j; 63 unsigned char L; 64 L = md->md2.chksum[15]; 65 for (j = 0; j < 16; j++) { 66 67 /* caution, the RFC says its "C[j] = S[M[i*16+j] xor L]" but the reference source code [and test vectors] say 68 otherwise. 69 */ 70 L = (md->md2.chksum[j] ^= PI_SUBST[(int)(md->md2.buf[j] ^ L)] & 255); 71 } 72 } 73 74 static void md2_compress(hash_state *md) 75 { 76 int j, k; 77 unsigned char t; 78 79 /* copy block */ 80 for (j = 0; j < 16; j++) { 81 md->md2.X[16+j] = md->md2.buf[j]; 82 md->md2.X[32+j] = md->md2.X[j] ^ md->md2.X[16+j]; 83 } 84 85 t = (unsigned char)0; 86 87 /* do 18 rounds */ 88 for (j = 0; j < 18; j++) { 89 for (k = 0; k < 48; k++) { 90 t = (md->md2.X[k] ^= PI_SUBST[(int)(t & 255)]); 91 } 92 t = (t + (unsigned char)j) & 255; 93 } 94 } 95 96 /** 97 Initialize the hash state 98 @param md The hash state you wish to initialize 99 @return CRYPT_OK if successful 100 */ 101 int md2_init(hash_state *md) 102 { 103 LTC_ARGCHK(md != NULL); 104 105 /* MD2 uses a zero'ed state... */ 106 zeromem(md->md2.X, sizeof(md->md2.X)); 107 zeromem(md->md2.chksum, sizeof(md->md2.chksum)); 108 zeromem(md->md2.buf, sizeof(md->md2.buf)); 109 md->md2.curlen = 0; 110 return CRYPT_OK; 111 } 112 113 /** 114 Process a block of memory though the hash 115 @param md The hash state 116 @param in The data to hash 117 @param inlen The length of the data (octets) 118 @return CRYPT_OK if successful 119 */ 120 int md2_process(hash_state *md, const unsigned char *in, unsigned long inlen) 121 { 122 unsigned long n; 123 LTC_ARGCHK(md != NULL); 124 LTC_ARGCHK(in != NULL); 125 if (md-> md2 .curlen > sizeof(md-> md2 .buf)) { 126 return CRYPT_INVALID_ARG; 127 } 128 while (inlen > 0) { 129 n = MIN(inlen, (16 - md->md2.curlen)); 130 XMEMCPY(md->md2.buf + md->md2.curlen, in, (size_t)n); 131 md->md2.curlen += n; 132 in += n; 133 inlen -= n; 134 135 /* is 16 bytes full? */ 136 if (md->md2.curlen == 16) { 137 md2_compress(md); 138 md2_update_chksum(md); 139 md->md2.curlen = 0; 140 } 141 } 142 return CRYPT_OK; 143 } 144 145 /** 146 Terminate the hash to get the digest 147 @param md The hash state 148 @param out [out] The destination of the hash (16 bytes) 149 @return CRYPT_OK if successful 150 */ 151 int md2_done(hash_state * md, unsigned char *out) 152 { 153 unsigned long i, k; 154 155 LTC_ARGCHK(md != NULL); 156 LTC_ARGCHK(out != NULL); 157 158 if (md->md2.curlen >= sizeof(md->md2.buf)) { 159 return CRYPT_INVALID_ARG; 160 } 161 162 163 /* pad the message */ 164 k = 16 - md->md2.curlen; 165 for (i = md->md2.curlen; i < 16; i++) { 166 md->md2.buf[i] = (unsigned char)k; 167 } 168 169 /* hash and update */ 170 md2_compress(md); 171 md2_update_chksum(md); 172 173 /* hash checksum */ 174 XMEMCPY(md->md2.buf, md->md2.chksum, 16); 175 md2_compress(md); 176 177 /* output is lower 16 bytes of X */ 178 XMEMCPY(out, md->md2.X, 16); 179 180 #ifdef LTC_CLEAN_STACK 181 zeromem(md, sizeof(hash_state)); 182 #endif 183 return CRYPT_OK; 184 } 185 186 /** 187 Self-test the hash 188 @return CRYPT_OK if successful, CRYPT_NOP if self-tests have been disabled 189 */ 190 int md2_test(void) 191 { 192 #ifndef LTC_TEST 193 return CRYPT_NOP; 194 #else 195 static const struct { 196 char *msg; 197 unsigned char md[16]; 198 } tests[] = { 199 { "", 200 {0x83,0x50,0xe5,0xa3,0xe2,0x4c,0x15,0x3d, 201 0xf2,0x27,0x5c,0x9f,0x80,0x69,0x27,0x73 202 } 203 }, 204 { "a", 205 {0x32,0xec,0x01,0xec,0x4a,0x6d,0xac,0x72, 206 0xc0,0xab,0x96,0xfb,0x34,0xc0,0xb5,0xd1 207 } 208 }, 209 { "message digest", 210 {0xab,0x4f,0x49,0x6b,0xfb,0x2a,0x53,0x0b, 211 0x21,0x9f,0xf3,0x30,0x31,0xfe,0x06,0xb0 212 } 213 }, 214 { "abcdefghijklmnopqrstuvwxyz", 215 {0x4e,0x8d,0xdf,0xf3,0x65,0x02,0x92,0xab, 216 0x5a,0x41,0x08,0xc3,0xaa,0x47,0x94,0x0b 217 } 218 }, 219 { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789", 220 {0xda,0x33,0xde,0xf2,0xa4,0x2d,0xf1,0x39, 221 0x75,0x35,0x28,0x46,0xc3,0x03,0x38,0xcd 222 } 223 }, 224 { "12345678901234567890123456789012345678901234567890123456789012345678901234567890", 225 {0xd5,0x97,0x6f,0x79,0xd8,0x3d,0x3a,0x0d, 226 0xc9,0x80,0x6c,0x3c,0x66,0xf3,0xef,0xd8 227 } 228 } 229 }; 230 int i; 231 hash_state md; 232 unsigned char buf[16]; 233 234 for (i = 0; i < (int)(sizeof(tests) / sizeof(tests[0])); i++) { 235 md2_init(&md); 236 md2_process(&md, (unsigned char*)tests[i].msg, (unsigned long)strlen(tests[i].msg)); 237 md2_done(&md, buf); 238 if (XMEMCMP(buf, tests[i].md, 16) != 0) { 239 return CRYPT_FAIL_TESTVECTOR; 240 } 241 } 242 return CRYPT_OK; 243 #endif 244 } 245 246 #endif 247 248 249 /* $Source: /cvs/libtom/libtomcrypt/src/hashes/md2.c,v $ */ 250 /* $Revision: 1.8 $ */ 251 /* $Date: 2006/11/01 09:28:17 $ */ 252
