lib/mdfour.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    a implementation of MD4 designed for use in the SMB authentication protocol
   5    Copyright (C) Andrew Tridgell 1997-1998.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "rsync.h"
  23
  24 /* NOTE: This code makes no attempt to be fast!
  25
  26    It assumes that a int is at least 32 bits long
  27 */
  28
  29 static struct mdfour *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
  61         ROUND2(A,B,C,D,  0,  3);  ROUND2(D,A,B,C,  4,  5);
  62         ROUND2(C,D,A,B,  8,  9);  ROUND2(B,C,D,A, 12, 13);
  63         ROUND2(A,B,C,D,  1,  3);  ROUND2(D,A,B,C,  5,  5);
  64         ROUND2(C,D,A,B,  9,  9);  ROUND2(B,C,D,A, 13, 13);
  65         ROUND2(A,B,C,D,  2,  3);  ROUND2(D,A,B,C,  6,  5);
  66         ROUND2(C,D,A,B, 10,  9);  ROUND2(B,C,D,A, 14, 13);
  67         ROUND2(A,B,C,D,  3,  3);  ROUND2(D,A,B,C,  7,  5);
  68         ROUND2(C,D,A,B, 11,  9);  ROUND2(B,C,D,A, 15, 13);
  69
  70         ROUND3(A,B,C,D,  0,  3);  ROUND3(D,A,B,C,  8,  9);
  71         ROUND3(C,D,A,B,  4, 11);  ROUND3(B,C,D,A, 12, 15);
  72         ROUND3(A,B,C,D,  2,  3);  ROUND3(D,A,B,C, 10,  9);
  73         ROUND3(C,D,A,B,  6, 11);  ROUND3(B,C,D,A, 14, 15);
  74         ROUND3(A,B,C,D,  1,  3);  ROUND3(D,A,B,C,  9,  9);
  75         ROUND3(C,D,A,B,  5, 11);  ROUND3(B,C,D,A, 13, 15);
  76         ROUND3(A,B,C,D,  3,  3);  ROUND3(D,A,B,C, 11,  9);
  77         ROUND3(C,D,A,B,  7, 11);  ROUND3(B,C,D,A, 15, 15);
  78
  79         A += AA; B += BB;
  80         C += CC; D += DD;
  81
  82         A &= MASK32; B &= MASK32;
  83         C &= MASK32; D &= MASK32;
  84
  85         m->A = A; m->B = B; m->C = C; m->D = D;
  86 }
  87
  88 static void copy64(uint32 *M, unsigned char *in)
  89 {
  90         int i;
  91
  92         for (i=0;i<16;i++)
  93                 M[i] = (in[i*4+3]<<24) | (in[i*4+2]<<16) |
  94                         (in[i*4+1]<<8) | (in[i*4+0]<<0);
  95 }
  96
  97 static void copy4(unsigned char *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(struct mdfour *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
 116 static void mdfour_tail(unsigned char *in, uint32 n)
 117 {
 118         unsigned char buf[128];
 119         uint32 M[16];
 120         extern int protocol_version;
 121
 122         /*
 123          * Count total number of bits, modulo 2^64
 124          */
 125         m->totalN += n << 3;
 126         if (m->totalN < (n << 3)) {
 127                 m->totalN2++;
 128         }
 129         m->totalN2 += n >> 29;
 130
 131         memset(buf, 0, 128);
 132         if (n) memcpy(buf, in, n);
 133         buf[n] = 0x80;
 134
 135         if (n <= 55) {
 136                 copy4(buf+56, m->totalN);
 137                 /*
 138                  * Prior to protocol version 27 only the number of bits
 139                  * modulo 2^32 was included.  MD4 requires the number
 140                  * of bits modulo 2^64, which was fixed starting with
 141                  * protocol version 27.
 142                  */
 143                 if (protocol_version >= 27) {
 144                         copy4(buf+60, m->totalN2);
 145                 }
 146                 copy64(M, buf);
 147                 mdfour64(M);
 148         } else {
 149                 copy4(buf+120, m->totalN);
 150                 /*
 151                  * Prior to protocol version 27 only the number of bits
 152                  * modulo 2^32 was included.  MD4 requires the number
 153                  * of bits modulo 2^64, which was fixed starting with
 154                  * protocol version 27.
 155                  */
 156                 if (protocol_version >= 27) {
 157                         copy4(buf+124, m->totalN2);
 158                 }
 159                 copy64(M, buf);
 160                 mdfour64(M);
 161                 copy64(M, buf+64);
 162                 mdfour64(M);
 163         }
 164 }
 165
 166 void mdfour_update(struct mdfour *md, unsigned char *in, uint32 n)
 167 {
 168         uint32 M[16];
 169
 170         m = md;
 171
 172         if (n == 0) mdfour_tail(in, n);
 173
 174         while (n >= 64) {
 175                 copy64(M, in);
 176                 mdfour64(M);
 177                 in += 64;
 178                 n -= 64;
 179                 m->totalN += 64 << 3;
 180                 if (m->totalN < 64 << 3) {
 181                         m->totalN2++;
 182                 }
 183         }
 184
 185         if (n) mdfour_tail(in, n);
 186 }
 187
 188
 189 void mdfour_result(struct mdfour *md, unsigned char *out)
 190 {
 191         m = md;
 192
 193         copy4(out, m->A);
 194         copy4(out+4, m->B);
 195         copy4(out+8, m->C);
 196         copy4(out+12, m->D);
 197 }
 198
 199
 200 void mdfour(unsigned char *out, unsigned char *in, int n)
 201 {
 202         struct mdfour md;
 203         mdfour_begin(&md);
 204         mdfour_update(&md, in, n);
 205         mdfour_result(&md, out);
 206 }
 207
 208 #ifdef TEST_MDFOUR
 209 int protocol_version = 28;
 210
 211 static void file_checksum1(char *fname)
 212 {
 213         int fd, i, was_multiple_of_64 = 1;
 214         struct mdfour md;
 215         unsigned char buf[64*1024], sum[16];
 216
 217         fd = open(fname,O_RDONLY);
 218         if (fd == -1) {
 219                 perror("fname");
 220                 exit(1);
 221         }
 222
 223         mdfour_begin(&md);
 224
 225         while (1) {
 226                 int n = read(fd, buf, sizeof(buf));
 227                 if (n <= 0)
 228                         break;
 229                 was_multiple_of_64 = !(n % 64);
 230                 mdfour_update(&md, buf, n);
 231         }
 232         if (was_multiple_of_64 && protocol_version >= 27)
 233                 mdfour_update(&md, buf, 0);
 234
 235         close(fd);
 236
 237         mdfour_result(&md, sum);
 238
 239         for (i=0;i<16;i++)
 240                 printf("%02X", sum[i]);
 241         printf("\n");
 242 }
 243
 244 #if 0
 245 #include "../md4.h"
 246
 247 static void file_checksum2(char *fname)
 248 {
 249         int fd, i;
 250         MDstruct md;
 251         unsigned char buf[64], sum[16];
 252
 253         fd = open(fname,O_RDONLY);
 254         if (fd == -1) {
 255                 perror("fname");
 256                 exit(1);
 257         }
 258
 259         MDbegin(&md);
 260
 261         while (1) {
 262                 int n = read(fd, buf, sizeof(buf));
 263                 if (n <= 0) break;
 264                 MDupdate(&md, buf, n*8);
 265         }
 266
 267         if (!md.done) {
 268                 MDupdate(&md, buf, 0);
 269         }
 270
 271         close(fd);
 272
 273         memcpy(sum, md.buffer, 16);
 274
 275         for (i=0;i<16;i++)
 276                 printf("%02X", sum[i]);
 277         printf("\n");
 278 }
 279 #endif
 280
 281  int main(int argc, char *argv[])
 282 {
 283         file_checksum1(argv[1]);
 284 #if 0
 285         file_checksum2(argv[1]);
 286 #endif
 287         return 0;
 288 }
 289 #endif