fs/cifs/smbdes.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4
   5    a partial implementation of DES designed for use in the
   6    SMB authentication protocol
   7
   8    Copyright (C) Andrew Tridgell 1998
   9    Modified by Steve French (sfrench@us.ibm.com) 2002,2004
  10
  11    This program is free software; you can redistribute it and/or modify
  12    it under the terms of the GNU General Public License as published by
  13    the Free Software Foundation; either version 2 of the License, or
  14    (at your option) any later version.
  15
  16    This program is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19    GNU General Public License for more details.
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program; if not, write to the Free Software
  23    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  24 */
  25
  26 /* NOTES:
  27
  28    This code makes no attempt to be fast! In fact, it is a very
  29    slow implementation
  30
  31    This code is NOT a complete DES implementation. It implements only
  32    the minimum necessary for SMB authentication, as used by all SMB
  33    products (including every copy of Microsoft Windows95 ever sold)
  34
  35    In particular, it can only do a unchained forward DES pass. This
  36    means it is not possible to use this code for encryption/decryption
  37    of data, instead it is only useful as a "hash" algorithm.
  38
  39    There is no entry point into this code that allows normal DES operation.
  40
  41    I believe this means that this code does not come under ITAR
  42    regulations but this is NOT a legal opinion. If you are concerned
  43    about the applicability of ITAR regulations to this code then you
  44    should confirm it for yourself (and maybe let me know if you come
  45    up with a different answer to the one above)
  46 */
  47 #include <linux/slab.h>
  48 #include "cifsencrypt.h"
  49 #define uchar unsigned char
  50
  51 static uchar perm1[56] = { 57, 49, 41, 33, 25, 17, 9,
  52         1, 58, 50, 42, 34, 26, 18,
  53         10, 2, 59, 51, 43, 35, 27,
  54         19, 11, 3, 60, 52, 44, 36,
  55         63, 55, 47, 39, 31, 23, 15,
  56         7, 62, 54, 46, 38, 30, 22,
  57         14, 6, 61, 53, 45, 37, 29,
  58         21, 13, 5, 28, 20, 12, 4
  59 };
  60
  61 static uchar perm2[48] = { 14, 17, 11, 24, 1, 5,
  62         3, 28, 15, 6, 21, 10,
  63         23, 19, 12, 4, 26, 8,
  64         16, 7, 27, 20, 13, 2,
  65         41, 52, 31, 37, 47, 55,
  66         30, 40, 51, 45, 33, 48,
  67         44, 49, 39, 56, 34, 53,
  68         46, 42, 50, 36, 29, 32
  69 };
  70
  71 static uchar perm3[64] = { 58, 50, 42, 34, 26, 18, 10, 2,
  72         60, 52, 44, 36, 28, 20, 12, 4,
  73         62, 54, 46, 38, 30, 22, 14, 6,
  74         64, 56, 48, 40, 32, 24, 16, 8,
  75         57, 49, 41, 33, 25, 17, 9, 1,
  76         59, 51, 43, 35, 27, 19, 11, 3,
  77         61, 53, 45, 37, 29, 21, 13, 5,
  78         63, 55, 47, 39, 31, 23, 15, 7
  79 };
  80
  81 static uchar perm4[48] = { 32, 1, 2, 3, 4, 5,
  82         4, 5, 6, 7, 8, 9,
  83         8, 9, 10, 11, 12, 13,
  84         12, 13, 14, 15, 16, 17,
  85         16, 17, 18, 19, 20, 21,
  86         20, 21, 22, 23, 24, 25,
  87         24, 25, 26, 27, 28, 29,
  88         28, 29, 30, 31, 32, 1
  89 };
  90
  91 static uchar perm5[32] = { 16, 7, 20, 21,
  92         29, 12, 28, 17,
  93         1, 15, 23, 26,
  94         5, 18, 31, 10,
  95         2, 8, 24, 14,
  96         32, 27, 3, 9,
  97         19, 13, 30, 6,
  98         22, 11, 4, 25
  99 };
 100
 101 static uchar perm6[64] = { 40, 8, 48, 16, 56, 24, 64, 32,
 102         39, 7, 47, 15, 55, 23, 63, 31,
 103         38, 6, 46, 14, 54, 22, 62, 30,
 104         37, 5, 45, 13, 53, 21, 61, 29,
 105         36, 4, 44, 12, 52, 20, 60, 28,
 106         35, 3, 43, 11, 51, 19, 59, 27,
 107         34, 2, 42, 10, 50, 18, 58, 26,
 108         33, 1, 41, 9, 49, 17, 57, 25
 109 };
 110
 111 static uchar sc[16] = { 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 };
 112
 113 static uchar sbox[8][4][16] = {
 114         {{14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7},
 115          {0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8},
 116          {4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0},
 117          {15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13}},
 118
 119         {{15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10},
 120          {3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5},
 121          {0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15},
 122          {13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9}},
 123
 124         {{10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8},
 125          {13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1},
 126          {13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7},
 127          {1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12}},
 128
 129         {{7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15},
 130          {13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9},
 131          {10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4},
 132          {3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14}},
 133
 134         {{2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9},
 135          {14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6},
 136          {4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14},
 137          {11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3}},
 138
 139         {{12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11},
 140          {10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8},
 141          {9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6},
 142          {4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13}},
 143
 144         {{4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1},
 145          {13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6},
 146          {1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2},
 147          {6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12}},
 148
 149         {{13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7},
 150          {1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2},
 151          {7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8},
 152          {2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11}}
 153 };
 154
 155 static void
 156 permute(char *out, char *in, uchar * p, int n)
 157 {
 158         int i;
 159         for (i = 0; i < n; i++)
 160                 out[i] = in[p[i] - 1];
 161 }
 162
 163 static void
 164 lshift(char *d, int count, int n)
 165 {
 166         char out[64];
 167         int i;
 168         for (i = 0; i < n; i++)
 169                 out[i] = d[(i + count) % n];
 170         for (i = 0; i < n; i++)
 171                 d[i] = out[i];
 172 }
 173
 174 static void
 175 concat(char *out, char *in1, char *in2, int l1, int l2)
 176 {
 177         while (l1--)
 178                 *out++ = *in1++;
 179         while (l2--)
 180                 *out++ = *in2++;
 181 }
 182
 183 static void
 184 xor(char *out, char *in1, char *in2, int n)
 185 {
 186         int i;
 187         for (i = 0; i < n; i++)
 188                 out[i] = in1[i] ^ in2[i];
 189 }
 190
 191 static void
 192 dohash(char *out, char *in, char *key, int forw)
 193 {
 194         int i, j, k;
 195         char *pk1;
 196         char c[28];
 197         char d[28];
 198         char *cd;
 199         char ki[16][48];
 200         char *pd1;
 201         char l[32], r[32];
 202         char *rl;
 203
 204         /* Have to reduce stack usage */
 205         pk1 = kmalloc(56+56+64+64,GFP_KERNEL);
 206         if(pk1 == NULL)
 207                 return;
 208
 209         cd = pk1 + 56;
 210         pd1= cd  + 56;
 211         rl = pd1 + 64;
 212
 213         permute(pk1, key, perm1, 56);
 214
 215         for (i = 0; i < 28; i++)
 216                 c[i] = pk1[i];
 217         for (i = 0; i < 28; i++)
 218                 d[i] = pk1[i + 28];
 219
 220         for (i = 0; i < 16; i++) {
 221                 lshift(c, sc[i], 28);
 222                 lshift(d, sc[i], 28);
 223
 224                 concat(cd, c, d, 28, 28);
 225                 permute(ki[i], cd, perm2, 48);
 226         }
 227
 228         permute(pd1, in, perm3, 64);
 229
 230         for (j = 0; j < 32; j++) {
 231                 l[j] = pd1[j];
 232                 r[j] = pd1[j + 32];
 233         }
 234
 235         for (i = 0; i < 16; i++) {
 236                 char *er;  /* er[48]  */
 237                 char *erk; /* erk[48] */
 238                 char b[8][6];
 239                 char *cb;  /* cb[32]  */
 240                 char *pcb; /* pcb[32] */
 241                 char *r2;  /* r2[32]  */
 242
 243                 er = kmalloc(48+48+32+32+32, GFP_KERNEL);
 244                 if(er == NULL) {
 245                         kfree(pk1);
 246                         return;
 247                 }
 248                 erk = er+48;
 249                 cb  = erk+48;
 250                 pcb = cb+32;
 251                 r2  = pcb+32;
 252
 253                 permute(er, r, perm4, 48);
 254
 255                 xor(erk, er, ki[forw ? i : 15 - i], 48);
 256
 257                 for (j = 0; j < 8; j++)
 258                         for (k = 0; k < 6; k++)
 259                                 b[j][k] = erk[j * 6 + k];
 260
 261                 for (j = 0; j < 8; j++) {
 262                         int m, n;
 263                         m = (b[j][0] << 1) | b[j][5];
 264
 265                         n = (b[j][1] << 3) | (b[j][2] << 2) | (b[j][3] <<
 266                                                                1) | b[j][4];
 267
 268                         for (k = 0; k < 4; k++)
 269                                 b[j][k] =
 270                                     (sbox[j][m][n] & (1 << (3 - k))) ? 1 : 0;
 271                 }
 272
 273                 for (j = 0; j < 8; j++)
 274                         for (k = 0; k < 4; k++)
 275                                 cb[j * 4 + k] = b[j][k];
 276                 permute(pcb, cb, perm5, 32);
 277
 278                 xor(r2, l, pcb, 32);
 279
 280                 for (j = 0; j < 32; j++)
 281                         l[j] = r[j];
 282
 283                 for (j = 0; j < 32; j++)
 284                         r[j] = r2[j];
 285
 286                 kfree(er);
 287         }
 288
 289         concat(rl, r, l, 32, 32);
 290
 291         permute(out, rl, perm6, 64);
 292         kfree(pk1);
 293 }
 294
 295 static void
 296 str_to_key(unsigned char *str, unsigned char *key)
 297 {
 298         int i;
 299
 300         key[0] = str[0] >> 1;
 301         key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
 302         key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
 303         key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
 304         key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
 305         key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
 306         key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
 307         key[7] = str[6] & 0x7F;
 308         for (i = 0; i < 8; i++) {
 309                 key[i] = (key[i] << 1);
 310         }
 311 }
 312
 313 static void
 314 smbhash(unsigned char *out, unsigned char *in, unsigned char *key, int forw)
 315 {
 316         int i;
 317         char *outb; /* outb[64] */
 318         char *inb;  /* inb[64]  */
 319         char *keyb; /* keyb[64] */
 320         unsigned char key2[8];
 321
 322         outb = kmalloc(64 * 3,GFP_KERNEL);
 323         if(outb == NULL)
 324                 return;
 325
 326         inb  = outb + 64;
 327         keyb = inb +  64;
 328
 329         str_to_key(key, key2);
 330
 331         for (i = 0; i < 64; i++) {
 332                 inb[i] = (in[i / 8] & (1 << (7 - (i % 8)))) ? 1 : 0;
 333                 keyb[i] = (key2[i / 8] & (1 << (7 - (i % 8)))) ? 1 : 0;
 334                 outb[i] = 0;
 335         }
 336
 337         dohash(outb, inb, keyb, forw);
 338
 339         for (i = 0; i < 8; i++) {
 340                 out[i] = 0;
 341         }
 342
 343         for (i = 0; i < 64; i++) {
 344                 if (outb[i])
 345                         out[i / 8] |= (1 << (7 - (i % 8)));
 346         }
 347         kfree(outb);
 348 }
 349
 350 void
 351 E_P16(unsigned char *p14, unsigned char *p16)
 352 {
 353         unsigned char sp8[8] =
 354             { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
 355         smbhash(p16, sp8, p14, 1);
 356         smbhash(p16 + 8, sp8, p14 + 7, 1);
 357 }
 358
 359 void
 360 E_P24(unsigned char *p21, unsigned char *c8, unsigned char *p24)
 361 {
 362         smbhash(p24, c8, p21, 1);
 363         smbhash(p24 + 8, c8, p21 + 7, 1);
 364         smbhash(p24 + 16, c8, p21 + 14, 1);
 365 }
 366
 367 #if 0 /* currently unsued */
 368 static void
 369 D_P16(unsigned char *p14, unsigned char *in, unsigned char *out)
 370 {
 371         smbhash(out, in, p14, 0);
 372         smbhash(out + 8, in + 8, p14 + 7, 0);
 373 }
 374
 375 static void
 376 E_old_pw_hash(unsigned char *p14, unsigned char *in, unsigned char *out)
 377 {
 378         smbhash(out, in, p14, 1);
 379         smbhash(out + 8, in + 8, p14 + 7, 1);
 380 }
 381 /* these routines are currently unneeded, but may be
 382         needed later */
 383 void
 384 cred_hash1(unsigned char *out, unsigned char *in, unsigned char *key)
 385 {
 386         unsigned char buf[8];
 387
 388         smbhash(buf, in, key, 1);
 389         smbhash(out, buf, key + 9, 1);
 390 }
 391
 392 void
 393 cred_hash2(unsigned char *out, unsigned char *in, unsigned char *key)
 394 {
 395         unsigned char buf[8];
 396         static unsigned char key2[8];
 397
 398         smbhash(buf, in, key, 1);
 399         key2[0] = key[7];
 400         smbhash(out, buf, key2, 1);
 401 }
 402
 403 void
 404 cred_hash3(unsigned char *out, unsigned char *in, unsigned char *key, int forw)
 405 {
 406         static unsigned char key2[8];
 407
 408         smbhash(out, in, key, forw);
 409         key2[0] = key[7];
 410         smbhash(out + 8, in + 8, key2, forw);
 411 }
 412 #endif /* unneeded routines */