lib/smblib/md4.c

   1 #include "squid.h"
   2
   3 /*
   4  * Unix SMB/Netbios implementation.
   5  * Version 1.9.
   6  * a implementation of MD4 designed for use in the SMB authentication protocol
   7  * Copyright (C) Andrew Tridgell 1997
   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 2 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
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  */
  23
  24 #include <string.h>
  25 #include "smblib/md4.h"
  26
  27 /* NOTE: This code makes no attempt to be fast!
  28  *
  29  * It assumes that a int is at least 32 bits long
  30  */
  31
  32 typedef unsigned int uint32;
  33
  34 static uint32 A, B, C, D;
  35
  36 static uint32
  37 F(uint32 X, uint32 Y, uint32 Z)
  38 {
  39     return (X & Y) | ((~X) & Z);
  40 }
  41
  42 static uint32
  43 G(uint32 X, uint32 Y, uint32 Z)
  44 {
  45     return (X & Y) | (X & Z) | (Y & Z);
  46 }
  47
  48 static uint32
  49 H(uint32 X, uint32 Y, uint32 Z)
  50 {
  51     return X ^ Y ^ Z;
  52 }
  53
  54 static uint32
  55 lshift(uint32 x, int s)
  56 {
  57     x &= 0xFFFFFFFF;
  58     return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s));
  59 }
  60
  61 #define ROUND1(a,b,c,d,k,s) a = lshift(a + F(b,c,d) + X[k], s)
  62 #define ROUND2(a,b,c,d,k,s) a = lshift(a + G(b,c,d) + X[k] + (uint32)0x5A827999,s)
  63 #define ROUND3(a,b,c,d,k,s) a = lshift(a + H(b,c,d) + X[k] + (uint32)0x6ED9EBA1,s)
  64
  65 /* this applies md4 to 64 byte chunks */
  66 static void
  67 mdfour64(uint32 * M)
  68 {
  69     int j;
  70     uint32 AA, BB, CC, DD;
  71     uint32 X[16];
  72
  73     for (j = 0; j < 16; j++)
  74         X[j] = M[j];
  75
  76     AA = A;
  77     BB = B;
  78     CC = C;
  79     DD = D;
  80
  81     ROUND1(A, B, C, D, 0, 3);
  82     ROUND1(D, A, B, C, 1, 7);
  83     ROUND1(C, D, A, B, 2, 11);
  84     ROUND1(B, C, D, A, 3, 19);
  85     ROUND1(A, B, C, D, 4, 3);
  86     ROUND1(D, A, B, C, 5, 7);
  87     ROUND1(C, D, A, B, 6, 11);
  88     ROUND1(B, C, D, A, 7, 19);
  89     ROUND1(A, B, C, D, 8, 3);
  90     ROUND1(D, A, B, C, 9, 7);
  91     ROUND1(C, D, A, B, 10, 11);
  92     ROUND1(B, C, D, A, 11, 19);
  93     ROUND1(A, B, C, D, 12, 3);
  94     ROUND1(D, A, B, C, 13, 7);
  95     ROUND1(C, D, A, B, 14, 11);
  96     ROUND1(B, C, D, A, 15, 19);
  97
  98     ROUND2(A, B, C, D, 0, 3);
  99     ROUND2(D, A, B, C, 4, 5);
 100     ROUND2(C, D, A, B, 8, 9);
 101     ROUND2(B, C, D, A, 12, 13);
 102     ROUND2(A, B, C, D, 1, 3);
 103     ROUND2(D, A, B, C, 5, 5);
 104     ROUND2(C, D, A, B, 9, 9);
 105     ROUND2(B, C, D, A, 13, 13);
 106     ROUND2(A, B, C, D, 2, 3);
 107     ROUND2(D, A, B, C, 6, 5);
 108     ROUND2(C, D, A, B, 10, 9);
 109     ROUND2(B, C, D, A, 14, 13);
 110     ROUND2(A, B, C, D, 3, 3);
 111     ROUND2(D, A, B, C, 7, 5);
 112     ROUND2(C, D, A, B, 11, 9);
 113     ROUND2(B, C, D, A, 15, 13);
 114
 115     ROUND3(A, B, C, D, 0, 3);
 116     ROUND3(D, A, B, C, 8, 9);
 117     ROUND3(C, D, A, B, 4, 11);
 118     ROUND3(B, C, D, A, 12, 15);
 119     ROUND3(A, B, C, D, 2, 3);
 120     ROUND3(D, A, B, C, 10, 9);
 121     ROUND3(C, D, A, B, 6, 11);
 122     ROUND3(B, C, D, A, 14, 15);
 123     ROUND3(A, B, C, D, 1, 3);
 124     ROUND3(D, A, B, C, 9, 9);
 125     ROUND3(C, D, A, B, 5, 11);
 126     ROUND3(B, C, D, A, 13, 15);
 127     ROUND3(A, B, C, D, 3, 3);
 128     ROUND3(D, A, B, C, 11, 9);
 129     ROUND3(C, D, A, B, 7, 11);
 130     ROUND3(B, C, D, A, 15, 15);
 131
 132     A += AA;
 133     B += BB;
 134     C += CC;
 135     D += DD;
 136
 137     A &= 0xFFFFFFFF;
 138     B &= 0xFFFFFFFF;
 139     C &= 0xFFFFFFFF;
 140     D &= 0xFFFFFFFF;
 141
 142     for (j = 0; j < 16; j++)
 143         X[j] = 0;
 144 }
 145
 146 static void
 147 copy64(uint32 * M, unsigned char *in)
 148 {
 149     int i;
 150
 151     for (i = 0; i < 16; i++)
 152         M[i] = (in[i * 4 + 3] << 24) | (in[i * 4 + 2] << 16) |
 153                (in[i * 4 + 1] << 8) | (in[i * 4 + 0] << 0);
 154 }
 155
 156 static void
 157 copy4(unsigned char *out, uint32 x)
 158 {
 159     out[0] = x & 0xFF;
 160     out[1] = (x >> 8) & 0xFF;
 161     out[2] = (x >> 16) & 0xFF;
 162     out[3] = (x >> 24) & 0xFF;
 163 }
 164
 165 /* produce a md4 message digest from data of length n bytes */
 166 void
 167 mdfour(unsigned char *out, unsigned char *in, int n)
 168 {
 169     unsigned char buf[128];
 170     uint32 M[16];
 171     uint32 b = n * 8;
 172     int i;
 173
 174     A = 0x67452301;
 175     B = 0xefcdab89;
 176     C = 0x98badcfe;
 177     D = 0x10325476;
 178
 179     while (n > 64) {
 180         copy64(M, in);
 181         mdfour64(M);
 182         in += 64;
 183         n -= 64;
 184     }
 185
 186     for (i = 0; i < 128; i++)
 187         buf[i] = 0;
 188     memcpy(buf, in, n);
 189     buf[n] = 0x80;
 190
 191     if (n <= 55) {
 192         copy4(buf + 56, b);
 193         copy64(M, buf);
 194         mdfour64(M);
 195     } else {
 196         copy4(buf + 120, b);
 197         copy64(M, buf);
 198         mdfour64(M);
 199         copy64(M, buf + 64);
 200         mdfour64(M);
 201     }
 202
 203     for (i = 0; i < 128; i++)
 204         buf[i] = 0;
 205     copy64(M, buf);
 206
 207     copy4(out, A);
 208     copy4(out + 4, B);
 209     copy4(out + 8, C);
 210     copy4(out + 12, D);
 211
 212     A = B = C = D = 0;
 213 }