source/libsmb/smbdes.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    a partial implementation of DES designed for use in the
   5    SMB authentication protocol
   6
   7    Copyright (C) Andrew Tridgell 1998
   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
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24
  25 /* NOTES:
  26
  27    This code makes no attempt to be fast! In fact, it is a very
  28    slow implementation
  29
  30    This code is NOT a complete DES implementation. It implements only
  31    the minimum necessary for SMB authentication, as used by all SMB
  32    products (including every copy of Microsoft Windows95 ever sold)
  33
  34    In particular, it can only do a unchained forward DES pass. This
  35    means it is not possible to use this code for encryption/decryption
  36    of data, instead it is only useful as a "hash" algorithm.
  37
  38    There is no entry point into this code that allows normal DES operation.
  39
  40    I believe this means that this code does not come under ITAR
  41    regulations but this is NOT a legal opinion. If you are concerned
  42    about the applicability of ITAR regulations to this code then you
  43    should confirm it for yourself (and maybe let me know if you come
  44    up with a different answer to the one above)
  45 */
  46
  47
  48 #define uchar unsigned char
  49
  50 static const uchar perm1[56] = {57, 49, 41, 33, 25, 17,  9,
  51                          1, 58, 50, 42, 34, 26, 18,
  52                         10,  2, 59, 51, 43, 35, 27,
  53                         19, 11,  3, 60, 52, 44, 36,
  54                         63, 55, 47, 39, 31, 23, 15,
  55                          7, 62, 54, 46, 38, 30, 22,
  56                         14,  6, 61, 53, 45, 37, 29,
  57                         21, 13,  5, 28, 20, 12,  4};
  58
  59 static const uchar perm2[48] = {14, 17, 11, 24,  1,  5,
  60                          3, 28, 15,  6, 21, 10,
  61                         23, 19, 12,  4, 26,  8,
  62                         16,  7, 27, 20, 13,  2,
  63                         41, 52, 31, 37, 47, 55,
  64                         30, 40, 51, 45, 33, 48,
  65                         44, 49, 39, 56, 34, 53,
  66                         46, 42, 50, 36, 29, 32};
  67
  68 static const uchar perm3[64] = {58, 50, 42, 34, 26, 18, 10,  2,
  69                         60, 52, 44, 36, 28, 20, 12,  4,
  70                         62, 54, 46, 38, 30, 22, 14,  6,
  71                         64, 56, 48, 40, 32, 24, 16,  8,
  72                         57, 49, 41, 33, 25, 17,  9,  1,
  73                         59, 51, 43, 35, 27, 19, 11,  3,
  74                         61, 53, 45, 37, 29, 21, 13,  5,
  75                         63, 55, 47, 39, 31, 23, 15,  7};
  76
  77 static const uchar perm4[48] = {   32,  1,  2,  3,  4,  5,
  78                             4,  5,  6,  7,  8,  9,
  79                             8,  9, 10, 11, 12, 13,
  80                            12, 13, 14, 15, 16, 17,
  81                            16, 17, 18, 19, 20, 21,
  82                            20, 21, 22, 23, 24, 25,
  83                            24, 25, 26, 27, 28, 29,
  84                            28, 29, 30, 31, 32,  1};
  85
  86 static const uchar perm5[32] = {      16,  7, 20, 21,
  87                               29, 12, 28, 17,
  88                                1, 15, 23, 26,
  89                                5, 18, 31, 10,
  90                                2,  8, 24, 14,
  91                               32, 27,  3,  9,
  92                               19, 13, 30,  6,
  93                               22, 11,  4, 25};
  94
  95
  96 static const uchar perm6[64] ={ 40,  8, 48, 16, 56, 24, 64, 32,
  97                         39,  7, 47, 15, 55, 23, 63, 31,
  98                         38,  6, 46, 14, 54, 22, 62, 30,
  99                         37,  5, 45, 13, 53, 21, 61, 29,
 100                         36,  4, 44, 12, 52, 20, 60, 28,
 101                         35,  3, 43, 11, 51, 19, 59, 27,
 102                         34,  2, 42, 10, 50, 18, 58, 26,
 103                         33,  1, 41,  9, 49, 17, 57, 25};
 104
 105
 106 static const uchar sc[16] = {1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1};
 107
 108 static const uchar sbox[8][4][16] = {
 109         {{14,  4, 13,  1,  2, 15, 11,  8,  3, 10,  6, 12,  5,  9,  0,  7},
 110          {0, 15,  7,  4, 14,  2, 13,  1, 10,  6, 12, 11,  9,  5,  3,  8},
 111          {4,  1, 14,  8, 13,  6,  2, 11, 15, 12,  9,  7,  3, 10,  5,  0},
 112          {15, 12,  8,  2,  4,  9,  1,  7,  5, 11,  3, 14, 10,  0,  6, 13}},
 113
 114         {{15,  1,  8, 14,  6, 11,  3,  4,  9,  7,  2, 13, 12,  0,  5, 10},
 115          {3, 13,  4,  7, 15,  2,  8, 14, 12,  0,  1, 10,  6,  9, 11,  5},
 116          {0, 14,  7, 11, 10,  4, 13,  1,  5,  8, 12,  6,  9,  3,  2, 15},
 117          {13,  8, 10,  1,  3, 15,  4,  2, 11,  6,  7, 12,  0,  5, 14,  9}},
 118
 119         {{10,  0,  9, 14,  6,  3, 15,  5,  1, 13, 12,  7, 11,  4,  2,  8},
 120          {13,  7,  0,  9,  3,  4,  6, 10,  2,  8,  5, 14, 12, 11, 15,  1},
 121          {13,  6,  4,  9,  8, 15,  3,  0, 11,  1,  2, 12,  5, 10, 14,  7},
 122          {1, 10, 13,  0,  6,  9,  8,  7,  4, 15, 14,  3, 11,  5,  2, 12}},
 123
 124         {{7, 13, 14,  3,  0,  6,  9, 10,  1,  2,  8,  5, 11, 12,  4, 15},
 125          {13,  8, 11,  5,  6, 15,  0,  3,  4,  7,  2, 12,  1, 10, 14,  9},
 126          {10,  6,  9,  0, 12, 11,  7, 13, 15,  1,  3, 14,  5,  2,  8,  4},
 127          {3, 15,  0,  6, 10,  1, 13,  8,  9,  4,  5, 11, 12,  7,  2, 14}},
 128
 129         {{2, 12,  4,  1,  7, 10, 11,  6,  8,  5,  3, 15, 13,  0, 14,  9},
 130          {14, 11,  2, 12,  4,  7, 13,  1,  5,  0, 15, 10,  3,  9,  8,  6},
 131          {4,  2,  1, 11, 10, 13,  7,  8, 15,  9, 12,  5,  6,  3,  0, 14},
 132          {11,  8, 12,  7,  1, 14,  2, 13,  6, 15,  0,  9, 10,  4,  5,  3}},
 133
 134         {{12,  1, 10, 15,  9,  2,  6,  8,  0, 13,  3,  4, 14,  7,  5, 11},
 135          {10, 15,  4,  2,  7, 12,  9,  5,  6,  1, 13, 14,  0, 11,  3,  8},
 136          {9, 14, 15,  5,  2,  8, 12,  3,  7,  0,  4, 10,  1, 13, 11,  6},
 137          {4,  3,  2, 12,  9,  5, 15, 10, 11, 14,  1,  7,  6,  0,  8, 13}},
 138
 139         {{4, 11,  2, 14, 15,  0,  8, 13,  3, 12,  9,  7,  5, 10,  6,  1},
 140          {13,  0, 11,  7,  4,  9,  1, 10, 14,  3,  5, 12,  2, 15,  8,  6},
 141          {1,  4, 11, 13, 12,  3,  7, 14, 10, 15,  6,  8,  0,  5,  9,  2},
 142          {6, 11, 13,  8,  1,  4, 10,  7,  9,  5,  0, 15, 14,  2,  3, 12}},
 143
 144         {{13,  2,  8,  4,  6, 15, 11,  1, 10,  9,  3, 14,  5,  0, 12,  7},
 145          {1, 15, 13,  8, 10,  3,  7,  4, 12,  5,  6, 11,  0, 14,  9,  2},
 146          {7, 11,  4,  1,  9, 12, 14,  2,  0,  6, 10, 13, 15,  3,  5,  8},
 147          {2,  1, 14,  7,  4, 10,  8, 13, 15, 12,  9,  0,  3,  5,  6, 11}}};
 148
 149 static void permute(char *out, const char *in, const uchar *p, int n)
 150 {
 151         int i;
 152         for (i=0;i<n;i++)
 153                 out[i] = in[p[i]-1];
 154 }
 155
 156 static void lshift(char *d, int count, int n)
 157 {
 158         char out[64];
 159         int i;
 160         for (i=0;i<n;i++)
 161                 out[i] = d[(i+count)%n];
 162         for (i=0;i<n;i++)
 163                 d[i] = out[i];
 164 }
 165
 166 static void concat(char *out, char *in1, char *in2, int l1, int l2)
 167 {
 168         while (l1--)
 169                 *out++ = *in1++;
 170         while (l2--)
 171                 *out++ = *in2++;
 172 }
 173
 174 static void x_or(char *out, char *in1, char *in2, int n)
 175 {
 176         int i;
 177         for (i=0;i<n;i++)
 178                 out[i] = in1[i] ^ in2[i];
 179 }
 180
 181 static void dohash(char *out, char *in, char *key, int forw)
 182 {
 183         int i, j, k;
 184         char pk1[56];
 185         char c[28];
 186         char d[28];
 187         char cd[56];
 188         char ki[16][48];
 189         char pd1[64];
 190         char l[32], r[32];
 191         char rl[64];
 192
 193         permute(pk1, key, perm1, 56);
 194
 195         for (i=0;i<28;i++)
 196                 c[i] = pk1[i];
 197         for (i=0;i<28;i++)
 198                 d[i] = pk1[i+28];
 199
 200         for (i=0;i<16;i++) {
 201                 lshift(c, sc[i], 28);
 202                 lshift(d, sc[i], 28);
 203
 204                 concat(cd, c, d, 28, 28);
 205                 permute(ki[i], cd, perm2, 48);
 206         }
 207
 208         permute(pd1, in, perm3, 64);
 209
 210         for (j=0;j<32;j++) {
 211                 l[j] = pd1[j];
 212                 r[j] = pd1[j+32];
 213         }
 214
 215         for (i=0;i<16;i++) {
 216                 char er[48];
 217                 char erk[48];
 218                 char b[8][6];
 219                 char cb[32];
 220                 char pcb[32];
 221                 char r2[32];
 222
 223                 permute(er, r, perm4, 48);
 224
 225                 x_or(erk, er, ki[forw ? i : 15 - i], 48);
 226
 227                 for (j=0;j<8;j++)
 228                         for (k=0;k<6;k++)
 229                                 b[j][k] = erk[j*6 + k];
 230
 231                 for (j=0;j<8;j++) {
 232                         int m, n;
 233                         m = (b[j][0]<<1) | b[j][5];
 234
 235                         n = (b[j][1]<<3) | (b[j][2]<<2) | (b[j][3]<<1) | b[j][4];
 236
 237                         for (k=0;k<4;k++)
 238                                 b[j][k] = (sbox[j][m][n] & (1<<(3-k)))?1:0;
 239                 }
 240
 241                 for (j=0;j<8;j++)
 242                         for (k=0;k<4;k++)
 243                                 cb[j*4+k] = b[j][k];
 244                 permute(pcb, cb, perm5, 32);
 245
 246                 x_or(r2, l, pcb, 32);
 247
 248                 for (j=0;j<32;j++)
 249                         l[j] = r[j];
 250
 251                 for (j=0;j<32;j++)
 252                         r[j] = r2[j];
 253         }
 254
 255         concat(rl, r, l, 32, 32);
 256
 257         permute(out, rl, perm6, 64);
 258 }
 259
 260 /* Convert a 7 byte string to an 8 byte key. */
 261 static void str_to_key(const unsigned char str[7], unsigned char key[8])
 262 {
 263         int i;
 264
 265         key[0] = str[0]>>1;
 266         key[1] = ((str[0]&0x01)<<6) | (str[1]>>2);
 267         key[2] = ((str[1]&0x03)<<5) | (str[2]>>3);
 268         key[3] = ((str[2]&0x07)<<4) | (str[3]>>4);
 269         key[4] = ((str[3]&0x0F)<<3) | (str[4]>>5);
 270         key[5] = ((str[4]&0x1F)<<2) | (str[5]>>6);
 271         key[6] = ((str[5]&0x3F)<<1) | (str[6]>>7);
 272         key[7] = str[6]&0x7F;
 273         for (i=0;i<8;i++) {
 274                 key[i] = (key[i]<<1);
 275         }
 276 }
 277
 278
 279 void des_crypt56(unsigned char *out, const unsigned char *in, const unsigned char *key, int forw)
 280 {
 281         int i;
 282         char outb[64];
 283         char inb[64];
 284         char keyb[64];
 285         unsigned char key2[8];
 286
 287         str_to_key(key, key2);
 288
 289         for (i=0;i<64;i++) {
 290                 inb[i] = (in[i/8] & (1<<(7-(i%8)))) ? 1 : 0;
 291                 keyb[i] = (key2[i/8] & (1<<(7-(i%8)))) ? 1 : 0;
 292                 outb[i] = 0;
 293         }
 294
 295         dohash(outb, inb, keyb, forw);
 296
 297         for (i=0;i<8;i++) {
 298                 out[i] = 0;
 299         }
 300
 301         for (i=0;i<64;i++) {
 302                 if (outb[i])
 303                         out[i/8] |= (1<<(7-(i%8)));
 304         }
 305 }
 306
 307 void E_P16(const unsigned char *p14,unsigned char *p16)
 308 {
 309         unsigned char sp8[8] = {0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25};
 310         des_crypt56(p16, sp8, p14, 1);
 311         des_crypt56(p16+8, sp8, p14+7, 1);
 312 }
 313
 314 void E_P24(const unsigned char *p21, const unsigned char *c8, unsigned char *p24)
 315 {
 316         des_crypt56(p24, c8, p21, 1);
 317         des_crypt56(p24+8, c8, p21+7, 1);
 318         des_crypt56(p24+16, c8, p21+14, 1);
 319 }
 320
 321 void D_P16(const unsigned char *p14, const unsigned char *in, unsigned char *out)
 322 {
 323         des_crypt56(out, in, p14, 0);
 324         des_crypt56(out+8, in+8, p14+7, 0);
 325 }
 326
 327 void E_old_pw_hash( unsigned char *p14, const unsigned char *in, unsigned char *out)
 328 {
 329         des_crypt56(out, in, p14, 1);
 330         des_crypt56(out+8, in+8, p14+7, 1);
 331 }
 332
 333 /* forward des encryption with a 128 bit key */
 334 void des_crypt128(unsigned char out[8], const unsigned char in[8], const unsigned char key[16])
 335 {
 336         unsigned char buf[8];
 337
 338         des_crypt56(buf, in, key, 1);
 339         des_crypt56(out, buf, key+9, 1);
 340 }
 341
 342 /* forward des encryption with a 64 bit key */
 343 void des_crypt64(unsigned char out[8], const unsigned char in[8], const unsigned char key[8])
 344 {
 345         unsigned char buf[8];
 346         unsigned char key2[8];
 347
 348         memset(key2,'\0',8);
 349         des_crypt56(buf, in, key, 1);
 350         key2[0] = key[7];
 351         des_crypt56(out, buf, key2, 1);
 352 }
 353
 354 /* des encryption with a 112 bit (14 byte) key */
 355 /* Note that if the forw is 1, and key is actually 8 bytes of key, followed by 6 bytes of zeros,
 356    this is identical to des_crypt64(). JRA. */
 357
 358 void des_crypt112(unsigned char out[8], const unsigned char in[8], const unsigned char key[14], int forw)
 359 {
 360         unsigned char buf[8];
 361         des_crypt56(buf, in, key, forw);
 362         des_crypt56(out, buf, key+7, forw);
 363 }
 364
 365 void cred_hash3(unsigned char *out, const unsigned char *in, const unsigned char *key, int forw)
 366 {
 367         unsigned char key2[8];
 368
 369         memset(key2,'\0',8);
 370         des_crypt56(out, in, key, forw);
 371         key2[0] = key[7];
 372         des_crypt56(out + 8, in + 8, key2, forw);
 373 }
 374
 375 /* des encryption of a 16 byte lump of data with a 112 bit key */
 376 /* Note that if the key is actually 8 bytes of key, followed by 6 bytes of zeros,
 377    this is identical to cred_hash3(). JRA. */
 378
 379 void des_crypt112_16(unsigned char out[16], unsigned char in[16], const unsigned char key[14], int forw)
 380 {
 381         des_crypt56(out, in, key, forw);
 382         des_crypt56(out + 8, in + 8, key+7, forw);
 383 }
 384
 385 /*****************************************************************
 386  arc4 crypt/decrypt with a 16 byte key.
 387 *****************************************************************/
 388
 389 void SamOEMhash( unsigned char *data, const unsigned char key[16], size_t len)
 390 {
 391         unsigned char arc4_state[258];
 392
 393         smb_arc4_init(arc4_state, key, 16);
 394         smb_arc4_crypt(arc4_state, data, len);
 395 }
 396
 397 void SamOEMhashBlob( unsigned char *data, size_t len, DATA_BLOB *key)
 398 {
 399         unsigned char arc4_state[258];
 400
 401         smb_arc4_init(arc4_state, key->data, key->length);
 402         smb_arc4_crypt(arc4_state, data, len);
 403 }
 404
 405 /* Decode a sam password hash into a password.  The password hash is the
 406    same method used to store passwords in the NT registry.  The DES key
 407    used is based on the RID of the user. */
 408
 409 void sam_pwd_hash(unsigned int rid, const uchar *in, uchar *out, int forw)
 410 {
 411         uchar s[14];
 412
 413         s[0] = s[4] = s[8] = s[12] = (uchar)(rid & 0xFF);
 414         s[1] = s[5] = s[9] = s[13] = (uchar)((rid >> 8) & 0xFF);
 415         s[2] = s[6] = s[10]        = (uchar)((rid >> 16) & 0xFF);
 416         s[3] = s[7] = s[11]        = (uchar)((rid >> 24) & 0xFF);
 417
 418         des_crypt56(out, in, s, forw);
 419         des_crypt56(out+8, in+8, s+7, forw);
 420 }