1 /* 2 * Copyright (C) 2001 Nikos Mavroyanopoulos 3 * Copyright (C) 2004 Hans Leidekker 4 * 5 * This library is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Lesser General Public 7 * License as published by the Free Software Foundation; either 8 * version 2.1 of the License, or (at your option) any later version. 9 * 10 * This library is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * Lesser General Public License for more details. 14 * 15 * You should have received a copy of the GNU Lesser General Public 16 * License along with this library; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA 18 */ 19 20 /* 21 * This code implements the MD4 message-digest algorithm. 22 * It is based on code in the public domain written by Colin 23 * Plumb in 1993. The algorithm is due to Ron Rivest. 24 * 25 * Equivalent code is available from RSA Data Security, Inc. 26 * This code has been tested against that, and is equivalent, 27 * except that you don't need to include two pages of legalese 28 * with every copy. 29 * 30 * To compute the message digest of a chunk of bytes, declare an 31 * MD4_CTX structure, pass it to MD4Init, call MD4Update as 32 * needed on buffers full of bytes, and then call MD4Final, which 33 * will fill a supplied 16-byte array with the digest. 34 */ 35 36 #include "md4.h" 37 #include "util.h" 38 39 static void MD4Transform( unsigned int buf[4], unsigned int const in[16] ); 40 41 /* 42 * Start MD4 accumulation. Set bit count to 0 and buffer to mysterious 43 * initialization constants. 44 */ 45 VOID NTAPI MD4Init( MD4_CTX *ctx ) 46 { 47 ctx->buf[0] = 0x67452301; 48 ctx->buf[1] = 0xefcdab89; 49 ctx->buf[2] = 0x98badcfe; 50 ctx->buf[3] = 0x10325476; 51 52 ctx->i[0] = ctx->i[1] = 0; 53 } 54 55 /* 56 * Update context to reflect the concatenation of another buffer full 57 * of bytes. 58 */ 59 VOID NTAPI MD4Update( MD4_CTX *ctx, const unsigned char *buf, unsigned int len ) 60 { 61 register unsigned int t; 62 63 /* Update bitcount */ 64 t = ctx->i[0]; 65 66 if ((ctx->i[0] = t + (len << 3)) < t) 67 ctx->i[1]++; /* Carry from low to high */ 68 69 ctx->i[1] += len >> 29; 70 t = (t >> 3) & 0x3f; 71 72 /* Handle any leading odd-sized chunks */ 73 if (t) 74 { 75 unsigned char *p = (unsigned char *)ctx->in + t; 76 t = 64 - t; 77 78 if (len < t) 79 { 80 memcpy( p, buf, len ); 81 return; 82 } 83 84 memcpy( p, buf, t ); 85 byteReverse( ctx->in, 16 ); 86 87 MD4Transform( ctx->buf, (unsigned int *)ctx->in ); 88 89 buf += t; 90 len -= t; 91 } 92 93 /* Process data in 64-byte chunks */ 94 while (len >= 64) 95 { 96 memcpy( ctx->in, buf, 64 ); 97 byteReverse( ctx->in, 16 ); 98 99 MD4Transform( ctx->buf, (unsigned int *)ctx->in ); 100 101 buf += 64; 102 len -= 64; 103 } 104 105 /* Handle any remaining bytes of data. */ 106 memcpy( ctx->in, buf, len ); 107 } 108 109 /* 110 * Final wrapup - pad to 64-byte boundary with the bit pattern 111 * 1 0* (64-bit count of bits processed, MSB-first) 112 */ 113 VOID NTAPI MD4Final( MD4_CTX *ctx ) 114 { 115 unsigned int count; 116 unsigned char *p; 117 118 /* Compute number of bytes mod 64 */ 119 count = (ctx->i[0] >> 3) & 0x3F; 120 121 /* Set the first char of padding to 0x80. This is safe since there is 122 always at least one byte free */ 123 p = ctx->in + count; 124 *p++ = 0x80; 125 126 /* Bytes of padding needed to make 64 bytes */ 127 count = 64 - 1 - count; 128 129 /* Pad out to 56 mod 64 */ 130 if (count < 8) 131 { 132 /* Two lots of padding: Pad the first block to 64 bytes */ 133 memset( p, 0, count ); 134 byteReverse( ctx->in, 16 ); 135 MD4Transform( ctx->buf, (unsigned int *)ctx->in ); 136 137 /* Now fill the next block with 56 bytes */ 138 memset( ctx->in, 0, 56 ); 139 } 140 else 141 { 142 /* Pad block to 56 bytes */ 143 memset( p, 0, count - 8 ); 144 } 145 146 byteReverse( ctx->in, 14 ); 147 148 /* Append length in bits and transform */ 149 ((unsigned int *)ctx->in)[14] = ctx->i[0]; 150 ((unsigned int *)ctx->in)[15] = ctx->i[1]; 151 152 MD4Transform( ctx->buf, (unsigned int *)ctx->in ); 153 byteReverse( (unsigned char *)ctx->buf, 4 ); 154 memcpy( ctx->digest, ctx->buf, 16 ); 155 memset(ctx->in, 0, sizeof(ctx->in)); 156 } 157 158 /* The three core functions */ 159 160 #define rotl32(x,n) (((x) << ((unsigned int)(n))) | ((x) >> (32 - (unsigned int)(n)))) 161 162 #define F( x, y, z ) (((x) & (y)) | ((~x) & (z))) 163 #define G( x, y, z ) (((x) & (y)) | ((x) & (z)) | ((y) & (z))) 164 #define H( x, y, z ) ((x) ^ (y) ^ (z)) 165 166 #define FF( a, b, c, d, x, s ) { \ 167 (a) += F( (b), (c), (d) ) + (x); \ 168 (a) = rotl32( (a), (s) ); \ 169 } 170 #define GG( a, b, c, d, x, s ) { \ 171 (a) += G( (b), (c), (d) ) + (x) + (unsigned int)0x5a827999; \ 172 (a) = rotl32( (a), (s) ); \ 173 } 174 #define HH( a, b, c, d, x, s ) { \ 175 (a) += H( (b), (c), (d) ) + (x) + (unsigned int)0x6ed9eba1; \ 176 (a) = rotl32( (a), (s) ); \ 177 } 178 179 /* 180 * The core of the MD4 algorithm 181 */ 182 static void MD4Transform( unsigned int buf[4], const unsigned int in[16] ) 183 { 184 register unsigned int a, b, c, d; 185 186 a = buf[0]; 187 b = buf[1]; 188 c = buf[2]; 189 d = buf[3]; 190 191 FF( a, b, c, d, in[0], 3 ); 192 FF( d, a, b, c, in[1], 7 ); 193 FF( c, d, a, b, in[2], 11 ); 194 FF( b, c, d, a, in[3], 19 ); 195 FF( a, b, c, d, in[4], 3 ); 196 FF( d, a, b, c, in[5], 7 ); 197 FF( c, d, a, b, in[6], 11 ); 198 FF( b, c, d, a, in[7], 19 ); 199 FF( a, b, c, d, in[8], 3 ); 200 FF( d, a, b, c, in[9], 7 ); 201 FF( c, d, a, b, in[10], 11 ); 202 FF( b, c, d, a, in[11], 19 ); 203 FF( a, b, c, d, in[12], 3 ); 204 FF( d, a, b, c, in[13], 7 ); 205 FF( c, d, a, b, in[14], 11 ); 206 FF( b, c, d, a, in[15], 19 ); 207 208 GG( a, b, c, d, in[0], 3 ); 209 GG( d, a, b, c, in[4], 5 ); 210 GG( c, d, a, b, in[8], 9 ); 211 GG( b, c, d, a, in[12], 13 ); 212 GG( a, b, c, d, in[1], 3 ); 213 GG( d, a, b, c, in[5], 5 ); 214 GG( c, d, a, b, in[9], 9 ); 215 GG( b, c, d, a, in[13], 13 ); 216 GG( a, b, c, d, in[2], 3 ); 217 GG( d, a, b, c, in[6], 5 ); 218 GG( c, d, a, b, in[10], 9 ); 219 GG( b, c, d, a, in[14], 13 ); 220 GG( a, b, c, d, in[3], 3 ); 221 GG( d, a, b, c, in[7], 5 ); 222 GG( c, d, a, b, in[11], 9 ); 223 GG( b, c, d, a, in[15], 13 ); 224 225 HH( a, b, c, d, in[0], 3 ); 226 HH( d, a, b, c, in[8], 9 ); 227 HH( c, d, a, b, in[4], 11 ); 228 HH( b, c, d, a, in[12], 15 ); 229 HH( a, b, c, d, in[2], 3 ); 230 HH( d, a, b, c, in[10], 9 ); 231 HH( c, d, a, b, in[6], 11 ); 232 HH( b, c, d, a, in[14], 15 ); 233 HH( a, b, c, d, in[1], 3 ); 234 HH( d, a, b, c, in[9], 9 ); 235 HH( c, d, a, b, in[5], 11 ); 236 HH( b, c, d, a, in[13], 15 ); 237 HH( a, b, c, d, in[3], 3 ); 238 HH( d, a, b, c, in[11], 9 ); 239 HH( c, d, a, b, in[7], 11 ); 240 HH( b, c, d, a, in[15], 15 ); 241 242 buf[0] += a; 243 buf[1] += b; 244 buf[2] += c; 245 buf[3] += d; 246 } 247 248