1 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm 2 */ 3 4 #include <sys/cdefs.h> 5 __FBSDID("$FreeBSD$"); 6 7 /*- 8 SPDX-License-Identifier: RSA-MD 9 10 Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved. 11 12 License to copy and use this software is granted provided that it 13 is identified as the "RSA Data Security, Inc. MD4 Message-Digest 14 Algorithm" in all material mentioning or referencing this software 15 or this function. 16 17 License is also granted to make and use derivative works provided 18 that such works are identified as "derived from the RSA Data 19 Security, Inc. MD4 Message-Digest Algorithm" in all material 20 mentioning or referencing the derived work. 21 22 RSA Data Security, Inc. makes no representations concerning either 23 the merchantability of this software or the suitability of this 24 software for any particular purpose. It is provided "as is" 25 without express or implied warranty of any kind. 26 27 These notices must be retained in any copies of any part of this 28 documentation and/or software. 29 */ 30 31 #include <sys/types.h> 32 #include <string.h> 33 #include "md4.h" 34 35 typedef unsigned char *POINTER; 36 typedef const unsigned char *CONST_POINTER; 37 typedef u_int16_t UINT2; 38 typedef u_int32_t UINT4; 39 40 #define PROTO_LIST(list) list 41 42 /* Constants for MD4Transform routine. 43 */ 44 #define S11 3 45 #define S12 7 46 #define S13 11 47 #define S14 19 48 #define S21 3 49 #define S22 5 50 #define S23 9 51 #define S24 13 52 #define S31 3 53 #define S32 9 54 #define S33 11 55 #define S34 15 56 57 static void MD4Transform PROTO_LIST ((UINT4 [4], const unsigned char [64])); 58 static void Encode PROTO_LIST 59 ((unsigned char *, UINT4 *, unsigned int)); 60 static void Decode PROTO_LIST 61 ((UINT4 *, const unsigned char *, unsigned int)); 62 63 static unsigned char PADDING[64] = { 64 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 65 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 66 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 67 }; 68 69 /* F, G and H are basic MD4 functions. 70 */ 71 #define F(x, y, z) (((x) & (y)) | ((~x) & (z))) 72 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z))) 73 #define H(x, y, z) ((x) ^ (y) ^ (z)) 74 75 /* ROTATE_LEFT rotates x left n bits. 76 */ 77 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n)))) 78 79 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */ 80 /* Rotation is separate from addition to prevent recomputation */ 81 #define FF(a, b, c, d, x, s) { \ 82 (a) += F ((b), (c), (d)) + (x); \ 83 (a) = ROTATE_LEFT ((a), (s)); \ 84 } 85 #define GG(a, b, c, d, x, s) { \ 86 (a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; \ 87 (a) = ROTATE_LEFT ((a), (s)); \ 88 } 89 #define HH(a, b, c, d, x, s) { \ 90 (a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; \ 91 (a) = ROTATE_LEFT ((a), (s)); \ 92 } 93 94 /* MD4 initialization. Begins an MD4 operation, writing a new context. 95 */ 96 void 97 MD4Init(MD4_CTX *context) 98 { 99 context->count[0] = context->count[1] = 0; 100 101 /* Load magic initialization constants. 102 */ 103 context->state[0] = 0x67452301; 104 context->state[1] = 0xefcdab89; 105 context->state[2] = 0x98badcfe; 106 context->state[3] = 0x10325476; 107 } 108 109 /* MD4 block update operation. Continues an MD4 message-digest 110 operation, processing another message block, and updating the 111 context. 112 */ 113 void 114 MD4Update(MD4_CTX *context, const void *in, unsigned int inputLen) 115 { 116 unsigned int i, idx, partLen; 117 const unsigned char *input = in; 118 119 /* Compute number of bytes mod 64 */ 120 idx = (unsigned int)((context->count[0] >> 3) & 0x3F); 121 /* Update number of bits */ 122 if ((context->count[0] += ((UINT4)inputLen << 3)) 123 < ((UINT4)inputLen << 3)) 124 context->count[1]++; 125 context->count[1] += ((UINT4)inputLen >> 29); 126 127 partLen = 64 - idx; 128 /* Transform as many times as possible. 129 */ 130 if (inputLen >= partLen) { 131 memcpy 132 ((POINTER)&context->buffer[idx], (CONST_POINTER)input, partLen); 133 MD4Transform (context->state, context->buffer); 134 135 for (i = partLen; i + 63 < inputLen; i += 64) 136 MD4Transform (context->state, &input[i]); 137 138 idx = 0; 139 } 140 else 141 i = 0; 142 143 /* Buffer remaining input */ 144 memcpy 145 ((POINTER)&context->buffer[idx], (CONST_POINTER)&input[i], 146 inputLen-i); 147 } 148 149 /* MD4 padding. */ 150 void 151 MD4Pad(MD4_CTX *context) 152 { 153 unsigned char bits[8]; 154 unsigned int idx, padLen; 155 156 /* Save number of bits */ 157 Encode (bits, context->count, 8); 158 159 /* Pad out to 56 mod 64. 160 */ 161 idx = (unsigned int)((context->count[0] >> 3) & 0x3f); 162 padLen = (idx < 56) ? (56 - idx) : (120 - idx); 163 MD4Update (context, PADDING, padLen); 164 165 /* Append length (before padding) */ 166 MD4Update (context, bits, 8); 167 } 168 169 /* MD4 finalization. Ends an MD4 message-digest operation, writing the 170 the message digest and zeroizing the context. 171 */ 172 void 173 MD4Final(unsigned char digest[16], MD4_CTX *context) 174 { 175 /* Do padding */ 176 MD4Pad (context); 177 178 /* Store state in digest */ 179 Encode (digest, context->state, 16); 180 181 /* Zeroize sensitive information. 182 */ 183 explicit_bzero(context, sizeof(*context)); 184 } 185 186 /* MD4 basic transformation. Transforms state based on block. 187 */ 188 static void 189 MD4Transform(UINT4 state[4], const unsigned char block[64]) 190 { 191 UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16]; 192 193 Decode (x, block, 64); 194 195 /* Round 1 */ 196 FF (a, b, c, d, x[ 0], S11); /* 1 */ 197 FF (d, a, b, c, x[ 1], S12); /* 2 */ 198 FF (c, d, a, b, x[ 2], S13); /* 3 */ 199 FF (b, c, d, a, x[ 3], S14); /* 4 */ 200 FF (a, b, c, d, x[ 4], S11); /* 5 */ 201 FF (d, a, b, c, x[ 5], S12); /* 6 */ 202 FF (c, d, a, b, x[ 6], S13); /* 7 */ 203 FF (b, c, d, a, x[ 7], S14); /* 8 */ 204 FF (a, b, c, d, x[ 8], S11); /* 9 */ 205 FF (d, a, b, c, x[ 9], S12); /* 10 */ 206 FF (c, d, a, b, x[10], S13); /* 11 */ 207 FF (b, c, d, a, x[11], S14); /* 12 */ 208 FF (a, b, c, d, x[12], S11); /* 13 */ 209 FF (d, a, b, c, x[13], S12); /* 14 */ 210 FF (c, d, a, b, x[14], S13); /* 15 */ 211 FF (b, c, d, a, x[15], S14); /* 16 */ 212 213 /* Round 2 */ 214 GG (a, b, c, d, x[ 0], S21); /* 17 */ 215 GG (d, a, b, c, x[ 4], S22); /* 18 */ 216 GG (c, d, a, b, x[ 8], S23); /* 19 */ 217 GG (b, c, d, a, x[12], S24); /* 20 */ 218 GG (a, b, c, d, x[ 1], S21); /* 21 */ 219 GG (d, a, b, c, x[ 5], S22); /* 22 */ 220 GG (c, d, a, b, x[ 9], S23); /* 23 */ 221 GG (b, c, d, a, x[13], S24); /* 24 */ 222 GG (a, b, c, d, x[ 2], S21); /* 25 */ 223 GG (d, a, b, c, x[ 6], S22); /* 26 */ 224 GG (c, d, a, b, x[10], S23); /* 27 */ 225 GG (b, c, d, a, x[14], S24); /* 28 */ 226 GG (a, b, c, d, x[ 3], S21); /* 29 */ 227 GG (d, a, b, c, x[ 7], S22); /* 30 */ 228 GG (c, d, a, b, x[11], S23); /* 31 */ 229 GG (b, c, d, a, x[15], S24); /* 32 */ 230 231 /* Round 3 */ 232 HH (a, b, c, d, x[ 0], S31); /* 33 */ 233 HH (d, a, b, c, x[ 8], S32); /* 34 */ 234 HH (c, d, a, b, x[ 4], S33); /* 35 */ 235 HH (b, c, d, a, x[12], S34); /* 36 */ 236 HH (a, b, c, d, x[ 2], S31); /* 37 */ 237 HH (d, a, b, c, x[10], S32); /* 38 */ 238 HH (c, d, a, b, x[ 6], S33); /* 39 */ 239 HH (b, c, d, a, x[14], S34); /* 40 */ 240 HH (a, b, c, d, x[ 1], S31); /* 41 */ 241 HH (d, a, b, c, x[ 9], S32); /* 42 */ 242 HH (c, d, a, b, x[ 5], S33); /* 43 */ 243 HH (b, c, d, a, x[13], S34); /* 44 */ 244 HH (a, b, c, d, x[ 3], S31); /* 45 */ 245 HH (d, a, b, c, x[11], S32); /* 46 */ 246 HH (c, d, a, b, x[ 7], S33); /* 47 */ 247 HH (b, c, d, a, x[15], S34); /* 48 */ 248 249 state[0] += a; 250 state[1] += b; 251 state[2] += c; 252 state[3] += d; 253 254 /* Zeroize sensitive information. 255 */ 256 memset ((POINTER)x, 0, sizeof (x)); 257 } 258 259 /* Encodes input (UINT4) into output (unsigned char). Assumes len is 260 a multiple of 4. 261 */ 262 static void 263 Encode(unsigned char *output, UINT4 *input, unsigned int len) 264 { 265 unsigned int i, j; 266 267 for (i = 0, j = 0; j < len; i++, j += 4) { 268 output[j] = (unsigned char)(input[i] & 0xff); 269 output[j+1] = (unsigned char)((input[i] >> 8) & 0xff); 270 output[j+2] = (unsigned char)((input[i] >> 16) & 0xff); 271 output[j+3] = (unsigned char)((input[i] >> 24) & 0xff); 272 } 273 } 274 275 /* Decodes input (unsigned char) into output (UINT4). Assumes len is 276 a multiple of 4. 277 */ 278 static void 279 Decode(UINT4 *output, const unsigned char *input, unsigned int len) 280 { 281 unsigned int i, j; 282 283 for (i = 0, j = 0; j < len; i++, j += 4) 284 output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) | 285 (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24); 286 } 287 288 #ifdef WEAK_REFS 289 /* When building libmd, provide weak references. Note: this is not 290 activated in the context of compiling these sources for internal 291 use in libcrypt. 292 */ 293 #undef MD4Init 294 __weak_reference(_libmd_MD4Init, MD4Init); 295 #undef MD4Update 296 __weak_reference(_libmd_MD4Update, MD4Update); 297 #undef MD4Pad 298 __weak_reference(_libmd_MD4Pad, MD4Pad); 299 #undef MD4Final 300 __weak_reference(_libmd_MD4Final, MD4Final); 301 #endif 302