lib/mdfour.c

   1 /*
   2  * Unix SMB/Netbios implementation.
   3  * Version 1.9.
   4  * An implementation of MD4 designed for use in the SMB authentication protocol.
   5  *
   6  * Copyright (C) 1997-1998 Andrew Tridgell
   7  * Copyright (C) 2005-2008 Wayne Davison
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 3 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, visit the http://fsf.org website.
  21  */
  22
  23 #include "rsync.h"
  24
  25 /* NOTE: This code makes no attempt to be fast!
  26  *
  27  * It assumes that a int is at least 32 bits long. */
  28
  29 static md_context *m;
  30
  31 #define MASK32 (0xffffffff)
  32
  33 #define F(X,Y,Z) ((((X)&(Y)) | ((~(X))&(Z))))
  34 #define G(X,Y,Z) ((((X)&(Y)) | ((X)&(Z)) | ((Y)&(Z))))
  35 #define H(X,Y,Z) (((X)^(Y)^(Z)))
  36 #define lshift(x,s) (((((x)<<(s))&MASK32) | (((x)>>(32-(s)))&MASK32)))
  37
  38 #define ROUND1(a,b,c,d,k,s) a = lshift((a + F(b,c,d) + M[k])&MASK32, s)
  39 #define ROUND2(a,b,c,d,k,s) a = lshift((a + G(b,c,d) + M[k] + 0x5A827999)&MASK32,s)
  40 #define ROUND3(a,b,c,d,k,s) a = lshift((a + H(b,c,d) + M[k] + 0x6ED9EBA1)&MASK32,s)
  41
  42 /* this applies md4 to 64 byte chunks */
  43 static void mdfour64(uint32 *M)
  44 {
  45         uint32 AA, BB, CC, DD;
  46         uint32 A,B,C,D;
  47
  48         A = m->A; B = m->B; C = m->C; D = m->D;
  49         AA = A; BB = B; CC = C; DD = D;
  50
  51         ROUND1(A,B,C,D,  0,  3);  ROUND1(D,A,B,C,  1,  7);
  52         ROUND1(C,D,A,B,  2, 11);  ROUND1(B,C,D,A,  3, 19);
  53         ROUND1(A,B,C,D,  4,  3);  ROUND1(D,A,B,C,  5,  7);
  54         ROUND1(C,D,A,B,  6, 11);  ROUND1(B,C,D,A,  7, 19);
  55         ROUND1(A,B,C,D,  8,  3);  ROUND1(D,A,B,C,  9,  7);
  56         ROUND1(C,D,A,B, 10, 11);  ROUND1(B,C,D,A, 11, 19);
  57         ROUND1(A,B,C,D, 12,  3);  ROUND1(D,A,B,C, 13,  7);
  58         ROUND1(C,D,A,B, 14, 11);  ROUND1(B,C,D,A, 15, 19);
  59
  60         ROUND2(A,B,C,D,  0,  3);  ROUND2(D,A,B,C,  4,  5);
  61         ROUND2(C,D,A,B,  8,  9);  ROUND2(B,C,D,A, 12, 13);
  62         ROUND2(A,B,C,D,  1,  3);  ROUND2(D,A,B,C,  5,  5);
  63         ROUND2(C,D,A,B,  9,  9);  ROUND2(B,C,D,A, 13, 13);
  64         ROUND2(A,B,C,D,  2,  3);  ROUND2(D,A,B,C,  6,  5);
  65         ROUND2(C,D,A,B, 10,  9);  ROUND2(B,C,D,A, 14, 13);
  66         ROUND2(A,B,C,D,  3,  3);  ROUND2(D,A,B,C,  7,  5);
  67         ROUND2(C,D,A,B, 11,  9);  ROUND2(B,C,D,A, 15, 13);
  68
  69         ROUND3(A,B,C,D,  0,  3);  ROUND3(D,A,B,C,  8,  9);
  70         ROUND3(C,D,A,B,  4, 11);  ROUND3(B,C,D,A, 12, 15);
  71         ROUND3(A,B,C,D,  2,  3);  ROUND3(D,A,B,C, 10,  9);
  72         ROUND3(C,D,A,B,  6, 11);  ROUND3(B,C,D,A, 14, 15);
  73         ROUND3(A,B,C,D,  1,  3);  ROUND3(D,A,B,C,  9,  9);
  74         ROUND3(C,D,A,B,  5, 11);  ROUND3(B,C,D,A, 13, 15);
  75         ROUND3(A,B,C,D,  3,  3);  ROUND3(D,A,B,C, 11,  9);
  76         ROUND3(C,D,A,B,  7, 11);  ROUND3(B,C,D,A, 15, 15);
  77
  78         A += AA; B += BB;
  79         C += CC; D += DD;
  80
  81         A &= MASK32; B &= MASK32;
  82         C &= MASK32; D &= MASK32;
  83
  84         m->A = A; m->B = B; m->C = C; m->D = D;
  85 }
  86
  87 static void copy64(uint32 *M, const uchar *in)
  88 {
  89         int i;
  90
  91         for (i = 0; i < MD4_DIGEST_LEN; i++) {
  92                 M[i] = (in[i*4+3] << 24) | (in[i*4+2] << 16)
  93                      | (in[i*4+1] << 8)  | (in[i*4+0] << 0);
  94         }
  95 }
  96
  97 static void copy4(uchar *out,uint32 x)
  98 {
  99         out[0] = x&0xFF;
 100         out[1] = (x>>8)&0xFF;
 101         out[2] = (x>>16)&0xFF;
 102         out[3] = (x>>24)&0xFF;
 103 }
 104
 105 void mdfour_begin(md_context *md)
 106 {
 107         md->A = 0x67452301;
 108         md->B = 0xefcdab89;
 109         md->C = 0x98badcfe;
 110         md->D = 0x10325476;
 111         md->totalN = 0;
 112         md->totalN2 = 0;
 113 }
 114
 115 static void mdfour_tail(const uchar *in, uint32 length)
 116 {
 117         uchar buf[128];
 118         uint32 M[16];
 119         extern int protocol_version;
 120
 121         /*
 122          * Count total number of bits, modulo 2^64
 123          */
 124         m->totalN += length << 3;
 125         if (m->totalN < (length << 3))
 126                 m->totalN2++;
 127         m->totalN2 += length >> 29;
 128
 129         memset(buf, 0, 128);
 130         if (length)
 131                 memcpy(buf, in, length);
 132         buf[length] = 0x80;
 133
 134         if (length <= 55) {
 135                 copy4(buf+56, m->totalN);
 136                 /*
 137                  * Prior to protocol version 27 only the number of bits
 138                  * modulo 2^32 was included.  MD4 requires the number
 139                  * of bits modulo 2^64, which was fixed starting with
 140                  * protocol version 27.
 141                  */
 142                 if (protocol_version >= 27)
 143                         copy4(buf+60, m->totalN2);
 144                 copy64(M, buf);
 145                 mdfour64(M);
 146         } else {
 147                 copy4(buf+120, m->totalN);
 148                 /*
 149                  * Prior to protocol version 27 only the number of bits
 150                  * modulo 2^32 was included.  MD4 requires the number
 151                  * of bits modulo 2^64, which was fixed starting with
 152                  * protocol version 27.
 153                  */
 154                 if (protocol_version >= 27)
 155                         copy4(buf+124, m->totalN2);
 156                 copy64(M, buf);
 157                 mdfour64(M);
 158                 copy64(M, buf+64);
 159                 mdfour64(M);
 160         }
 161 }
 162
 163 void mdfour_update(md_context *md, const uchar *in, uint32 length)
 164 {
 165         uint32 M[16];
 166
 167         m = md;
 168
 169         if (length == 0)
 170                 mdfour_tail(in, length);
 171
 172         while (length >= 64) {
 173                 copy64(M, in);
 174                 mdfour64(M);
 175                 in += 64;
 176                 length -= 64;
 177                 m->totalN += 64 << 3;
 178                 if (m->totalN < 64 << 3)
 179                         m->totalN2++;
 180         }
 181
 182         if (length)
 183                 mdfour_tail(in, length);
 184 }
 185
 186 void mdfour_result(md_context *md, uchar digest[MD4_DIGEST_LEN])
 187 {
 188         m = md;
 189
 190         copy4(digest, m->A);
 191         copy4(digest+4, m->B);
 192         copy4(digest+8, m->C);
 193         copy4(digest+12, m->D);
 194 }
 195
 196 void mdfour(uchar digest[MD4_DIGEST_LEN], uchar *in, int length)
 197 {
 198         md_context md;
 199         mdfour_begin(&md);
 200         mdfour_update(&md, in, length);
 201         mdfour_result(&md, digest);
 202 }
 203
 204 #ifdef TEST_MDFOUR
 205 int protocol_version = 28;
 206
 207 static void file_checksum1(char *fname)
 208 {
 209         int fd, i, was_multiple_of_64 = 1;
 210         md_context md;
 211         uchar buf[64*1024], sum[MD4_DIGEST_LEN];
 212
 213         fd = open(fname,O_RDONLY);
 214         if (fd == -1) {
 215                 perror("fname");
 216                 exit(1);
 217         }
 218
 219         mdfour_begin(&md);
 220
 221         while (1) {
 222                 int n = read(fd, buf, sizeof buf);
 223                 if (n <= 0)
 224                         break;
 225                 was_multiple_of_64 = !(n % 64);
 226                 mdfour_update(&md, buf, n);
 227         }
 228         if (was_multiple_of_64 && protocol_version >= 27)
 229                 mdfour_update(&md, buf, 0);
 230
 231         close(fd);
 232
 233         mdfour_result(&md, sum);
 234
 235         for (i = 0; i < MD4_DIGEST_LEN; i++)
 236                 printf("%02X", sum[i]);
 237         printf("\n");
 238 }
 239
 240  int main(int argc, char *argv[])
 241 {
 242         while (--argc)
 243                 file_checksum1(*++argv);
 244         return 0;
 245 }
 246 #endif