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)[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         ki = kmalloc(16*48, GFP_KERNEL);
 210         if (ki == NULL) {
 211                 kfree(pk1);
 212                 return;
 213         }
 214
 215         cd = pk1 + 56;
 216         pd1 = cd  + 56;
 217         rl = pd1 + 64;
 218
 219         permute(pk1, key, perm1, 56);
 220
 221         for (i = 0; i < 28; i++)
 222                 c[i] = pk1[i];
 223         for (i = 0; i < 28; i++)
 224                 d[i] = pk1[i + 28];
 225
 226         for (i = 0; i < 16; i++) {
 227                 lshift(c, sc[i], 28);
 228                 lshift(d, sc[i], 28);
 229
 230                 concat(cd, c, d, 28, 28);
 231                 permute(ki[i], cd, perm2, 48);
 232         }
 233
 234         permute(pd1, in, perm3, 64);
 235
 236         for (j = 0; j < 32; j++) {
 237                 l[j] = pd1[j];
 238                 r[j] = pd1[j + 32];
 239         }
 240
 241         for (i = 0; i < 16; i++) {
 242                 char *er;  /* er[48]  */
 243                 char *erk; /* erk[48] */
 244                 char b[8][6];
 245                 char *cb;  /* cb[32]  */
 246                 char *pcb; /* pcb[32] */
 247                 char *r2;  /* r2[32]  */
 248
 249                 er = kmalloc(48+48+32+32+32, GFP_KERNEL);
 250                 if (er == NULL) {
 251                         kfree(pk1);
 252                         kfree(ki);
 253                         return;
 254                 }
 255                 erk = er+48;
 256                 cb  = erk+48;
 257                 pcb = cb+32;
 258                 r2  = pcb+32;
 259
 260                 permute(er, r, perm4, 48);
 261
 262                 xor(erk, er, ki[forw ? i : 15 - i], 48);
 263
 264                 for (j = 0; j < 8; j++)
 265                         for (k = 0; k < 6; k++)
 266                                 b[j][k] = erk[j * 6 + k];
 267
 268                 for (j = 0; j < 8; j++) {
 269                         int m, n;
 270                         m = (b[j][0] << 1) | b[j][5];
 271
 272                         n = (b[j][1] << 3) | (b[j][2] << 2) | (b[j][3] <<
 273                                                                1) | b[j][4];
 274
 275                         for (k = 0; k < 4; k++)
 276                                 b[j][k] =
 277                                     (sbox[j][m][n] & (1 << (3 - k))) ? 1 : 0;
 278                 }
 279
 280                 for (j = 0; j < 8; j++)
 281                         for (k = 0; k < 4; k++)
 282                                 cb[j * 4 + k] = b[j][k];
 283                 permute(pcb, cb, perm5, 32);
 284
 285                 xor(r2, l, pcb, 32);
 286
 287                 for (j = 0; j < 32; j++)
 288                         l[j] = r[j];
 289
 290                 for (j = 0; j < 32; j++)
 291                         r[j] = r2[j];
 292
 293                 kfree(er);
 294         }
 295
 296         concat(rl, r, l, 32, 32);
 297
 298         permute(out, rl, perm6, 64);
 299         kfree(pk1);
 300         kfree(ki);
 301 }
 302
 303 static void
 304 str_to_key(unsigned char *str, unsigned char *key)
 305 {
 306         int i;
 307
 308         key[0] = str[0] >> 1;
 309         key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
 310         key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
 311         key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
 312         key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
 313         key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
 314         key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
 315         key[7] = str[6] & 0x7F;
 316         for (i = 0; i < 8; i++)
 317                 key[i] = (key[i] << 1);
 318 }
 319
 320 static void
 321 smbhash(unsigned char *out, const unsigned char *in, unsigned char *key,
 322         int forw)
 323 {
 324         int i;
 325         char *outb; /* outb[64] */
 326         char *inb;  /* inb[64]  */
 327         char *keyb; /* keyb[64] */
 328         unsigned char key2[8];
 329
 330         outb = kmalloc(64 * 3, GFP_KERNEL);
 331         if (outb == NULL)
 332                 return;
 333
 334         inb  = outb + 64;
 335         keyb = inb +  64;
 336
 337         str_to_key(key, key2);
 338
 339         for (i = 0; i < 64; i++) {
 340                 inb[i] = (in[i / 8] & (1 << (7 - (i % 8)))) ? 1 : 0;
 341                 keyb[i] = (key2[i / 8] & (1 << (7 - (i % 8)))) ? 1 : 0;
 342                 outb[i] = 0;
 343         }
 344
 345         dohash(outb, inb, keyb, forw);
 346
 347         for (i = 0; i < 8; i++)
 348                 out[i] = 0;
 349
 350         for (i = 0; i < 64; i++) {
 351                 if (outb[i])
 352                         out[i / 8] |= (1 << (7 - (i % 8)));
 353         }
 354         kfree(outb);
 355 }
 356
 357 void
 358 E_P16(unsigned char *p14, unsigned char *p16)
 359 {
 360         unsigned char sp8[8] =
 361             { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
 362         smbhash(p16, sp8, p14, 1);
 363         smbhash(p16 + 8, sp8, p14 + 7, 1);
 364 }
 365
 366 void
 367 E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
 368 {
 369         smbhash(p24, c8, p21, 1);
 370         smbhash(p24 + 8, c8, p21 + 7, 1);
 371         smbhash(p24 + 16, c8, p21 + 14, 1);
 372 }
 373
 374 #if 0 /* currently unsued */
 375 static void
 376 D_P16(unsigned char *p14, unsigned char *in, unsigned char *out)
 377 {
 378         smbhash(out, in, p14, 0);
 379         smbhash(out + 8, in + 8, p14 + 7, 0);
 380 }
 381
 382 static void
 383 E_old_pw_hash(unsigned char *p14, unsigned char *in, unsigned char *out)
 384 {
 385         smbhash(out, in, p14, 1);
 386         smbhash(out + 8, in + 8, p14 + 7, 1);
 387 }
 388 /* these routines are currently unneeded, but may be
 389         needed later */
 390 void
 391 cred_hash1(unsigned char *out, unsigned char *in, unsigned char *key)
 392 {
 393         unsigned char buf[8];
 394
 395         smbhash(buf, in, key, 1);
 396         smbhash(out, buf, key + 9, 1);
 397 }
 398
 399 void
 400 cred_hash2(unsigned char *out, unsigned char *in, unsigned char *key)
 401 {
 402         unsigned char buf[8];
 403         static unsigned char key2[8];
 404
 405         smbhash(buf, in, key, 1);
 406         key2[0] = key[7];
 407         smbhash(out, buf, key2, 1);
 408 }
 409
 410 void
 411 cred_hash3(unsigned char *out, unsigned char *in, unsigned char *key, int forw)
 412 {
 413         static unsigned char key2[8];
 414
 415         smbhash(out, in, key, forw);
 416         key2[0] = key[7];
 417         smbhash(out + 8, in + 8, key2, forw);
 418 }
 419 #endif /* unneeded routines */