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