fs/cifs/smbencrypt.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    SMB parameters and setup
   5    Copyright (C) Andrew Tridgell 1992-2000
   6    Copyright (C) Luke Kenneth Casson Leighton 1996-2000
   7    Modified by Jeremy Allison 1995.
   8    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2002-2003
   9    Modified by Steve French (sfrench@us.ibm.com) 2002-2003
  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 #include <linux/module.h>
  27 #include <linux/slab.h>
  28 #include <linux/fs.h>
  29 #include <linux/string.h>
  30 #include <linux/kernel.h>
  31 #include <linux/random.h>
  32 #include "cifs_unicode.h"
  33 #include "cifspdu.h"
  34 #include "cifsglob.h"
  35 #include "cifs_debug.h"
  36 #include "cifsproto.h"
  37
  38 #ifndef false
  39 #define false 0
  40 #endif
  41 #ifndef true
  42 #define true 1
  43 #endif
  44
  45 /* following came from the other byteorder.h to avoid include conflicts */
  46 #define CVAL(buf,pos) (((unsigned char *)(buf))[pos])
  47 #define SSVALX(buf,pos,val) (CVAL(buf,pos)=(val)&0xFF,CVAL(buf,pos+1)=(val)>>8)
  48 #define SSVAL(buf,pos,val) SSVALX((buf),(pos),((__u16)(val)))
  49
  50 static void
  51 str_to_key(unsigned char *str, unsigned char *key)
  52 {
  53         int i;
  54
  55         key[0] = str[0] >> 1;
  56         key[1] = ((str[0] & 0x01) << 6) | (str[1] >> 2);
  57         key[2] = ((str[1] & 0x03) << 5) | (str[2] >> 3);
  58         key[3] = ((str[2] & 0x07) << 4) | (str[3] >> 4);
  59         key[4] = ((str[3] & 0x0F) << 3) | (str[4] >> 5);
  60         key[5] = ((str[4] & 0x1F) << 2) | (str[5] >> 6);
  61         key[6] = ((str[5] & 0x3F) << 1) | (str[6] >> 7);
  62         key[7] = str[6] & 0x7F;
  63         for (i = 0; i < 8; i++)
  64                 key[i] = (key[i] << 1);
  65 }
  66
  67 static int
  68 smbhash(unsigned char *out, const unsigned char *in, unsigned char *key)
  69 {
  70         int rc;
  71         unsigned char key2[8];
  72         struct crypto_blkcipher *tfm_des;
  73         struct scatterlist sgin, sgout;
  74         struct blkcipher_desc desc;
  75
  76         str_to_key(key, key2);
  77
  78         tfm_des = crypto_alloc_blkcipher("ecb(des)", 0, CRYPTO_ALG_ASYNC);
  79         if (IS_ERR(tfm_des)) {
  80                 rc = PTR_ERR(tfm_des);
  81                 cERROR(1, "could not allocate des crypto API\n");
  82                 goto smbhash_err;
  83         }
  84
  85         desc.tfm = tfm_des;
  86
  87         crypto_blkcipher_setkey(tfm_des, key2, 8);
  88
  89         sg_init_one(&sgin, in, 8);
  90         sg_init_one(&sgout, out, 8);
  91
  92         rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, 8);
  93         if (rc)
  94                 cERROR(1, "could not encrypt crypt key rc: %d\n", rc);
  95
  96         crypto_free_blkcipher(tfm_des);
  97 smbhash_err:
  98         return rc;
  99 }
 100
 101 static int
 102 E_P16(unsigned char *p14, unsigned char *p16)
 103 {
 104         int rc;
 105         unsigned char sp8[8] =
 106             { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
 107
 108         rc = smbhash(p16, sp8, p14);
 109         if (rc)
 110                 return rc;
 111         rc = smbhash(p16 + 8, sp8, p14 + 7);
 112         return rc;
 113 }
 114
 115 static int
 116 E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
 117 {
 118         int rc;
 119
 120         rc = smbhash(p24, c8, p21);
 121         if (rc)
 122                 return rc;
 123         rc = smbhash(p24 + 8, c8, p21 + 7);
 124         if (rc)
 125                 return rc;
 126         rc = smbhash(p24 + 16, c8, p21 + 14);
 127         return rc;
 128 }
 129
 130 /* produce a md4 message digest from data of length n bytes */
 131 int
 132 mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
 133 {
 134         int rc;
 135         unsigned int size;
 136         struct crypto_shash *md4;
 137         struct sdesc *sdescmd4;
 138
 139         md4 = crypto_alloc_shash("md4", 0, 0);
 140         if (IS_ERR(md4)) {
 141                 rc = PTR_ERR(md4);
 142                 cERROR(1, "%s: Crypto md4 allocation error %d\n", __func__, rc);
 143                 return rc;
 144         }
 145         size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
 146         sdescmd4 = kmalloc(size, GFP_KERNEL);
 147         if (!sdescmd4) {
 148                 rc = -ENOMEM;
 149                 cERROR(1, "%s: Memory allocation failure\n", __func__);
 150                 goto mdfour_err;
 151         }
 152         sdescmd4->shash.tfm = md4;
 153         sdescmd4->shash.flags = 0x0;
 154
 155         rc = crypto_shash_init(&sdescmd4->shash);
 156         if (rc) {
 157                 cERROR(1, "%s: Could not init md4 shash\n", __func__);
 158                 goto mdfour_err;
 159         }
 160         crypto_shash_update(&sdescmd4->shash, link_str, link_len);
 161         rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
 162
 163 mdfour_err:
 164         crypto_free_shash(md4);
 165         kfree(sdescmd4);
 166
 167         return rc;
 168 }
 169
 170 /*
 171    This implements the X/Open SMB password encryption
 172    It takes a password, a 8 byte "crypt key" and puts 24 bytes of
 173    encrypted password into p24 */
 174 /* Note that password must be uppercased and null terminated */
 175 int
 176 SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
 177 {
 178         int rc;
 179         unsigned char p14[14], p16[16], p21[21];
 180
 181         memset(p14, '\0', 14);
 182         memset(p16, '\0', 16);
 183         memset(p21, '\0', 21);
 184
 185         memcpy(p14, passwd, 14);
 186         rc = E_P16(p14, p16);
 187         if (rc)
 188                 return rc;
 189
 190         memcpy(p21, p16, 16);
 191         rc = E_P24(p21, c8, p24);
 192
 193         return rc;
 194 }
 195
 196 /* Routines for Windows NT MD4 Hash functions. */
 197 static int
 198 _my_wcslen(__u16 *str)
 199 {
 200         int len = 0;
 201         while (*str++ != 0)
 202                 len++;
 203         return len;
 204 }
 205
 206 /*
 207  * Convert a string into an NT UNICODE string.
 208  * Note that regardless of processor type
 209  * this must be in intel (little-endian)
 210  * format.
 211  */
 212
 213 static int
 214 _my_mbstowcs(__u16 *dst, const unsigned char *src, int len)
 215 {       /* BB not a very good conversion routine - change/fix */
 216         int i;
 217         __u16 val;
 218
 219         for (i = 0; i < len; i++) {
 220                 val = *src;
 221                 SSVAL(dst, 0, val);
 222                 dst++;
 223                 src++;
 224                 if (val == 0)
 225                         break;
 226         }
 227         return i;
 228 }
 229
 230 /*
 231  * Creates the MD4 Hash of the users password in NT UNICODE.
 232  */
 233
 234 int
 235 E_md4hash(const unsigned char *passwd, unsigned char *p16)
 236 {
 237         int rc;
 238         int len;
 239         __u16 wpwd[129];
 240
 241         /* Password cannot be longer than 128 characters */
 242         if (passwd) {
 243                 len = strlen((char *) passwd);
 244                 if (len > 128)
 245                         len = 128;
 246
 247                 /* Password must be converted to NT unicode */
 248                 _my_mbstowcs(wpwd, passwd, len);
 249         } else
 250                 len = 0;
 251
 252         wpwd[len] = 0;  /* Ensure string is null terminated */
 253         /* Calculate length in bytes */
 254         len = _my_wcslen(wpwd) * sizeof(__u16);
 255
 256         rc = mdfour(p16, (unsigned char *) wpwd, len);
 257         memset(wpwd, 0, 129 * 2);
 258
 259         return rc;
 260 }
 261
 262 #if 0 /* currently unused */
 263 /* Does both the NT and LM owfs of a user's password */
 264 static void
 265 nt_lm_owf_gen(char *pwd, unsigned char nt_p16[16], unsigned char p16[16])
 266 {
 267         char passwd[514];
 268
 269         memset(passwd, '\0', 514);
 270         if (strlen(pwd) < 513)
 271                 strcpy(passwd, pwd);
 272         else
 273                 memcpy(passwd, pwd, 512);
 274         /* Calculate the MD4 hash (NT compatible) of the password */
 275         memset(nt_p16, '\0', 16);
 276         E_md4hash(passwd, nt_p16);
 277
 278         /* Mangle the passwords into Lanman format */
 279         passwd[14] = '\0';
 280 /*      strupper(passwd); */
 281
 282         /* Calculate the SMB (lanman) hash functions of the password */
 283
 284         memset(p16, '\0', 16);
 285         E_P16((unsigned char *) passwd, (unsigned char *) p16);
 286
 287         /* clear out local copy of user's password (just being paranoid). */
 288         memset(passwd, '\0', sizeof(passwd));
 289 }
 290 #endif
 291
 292 /* Does the NTLMv2 owfs of a user's password */
 293 #if 0  /* function not needed yet - but will be soon */
 294 static void
 295 ntv2_owf_gen(const unsigned char owf[16], const char *user_n,
 296                 const char *domain_n, unsigned char kr_buf[16],
 297                 const struct nls_table *nls_codepage)
 298 {
 299         wchar_t *user_u;
 300         wchar_t *dom_u;
 301         int user_l, domain_l;
 302         struct HMACMD5Context ctx;
 303
 304         /* might as well do one alloc to hold both (user_u and dom_u) */
 305         user_u = kmalloc(2048 * sizeof(wchar_t), GFP_KERNEL);
 306         if (user_u == NULL)
 307                 return;
 308         dom_u = user_u + 1024;
 309
 310         /* push_ucs2(NULL, user_u, user_n, (user_l+1)*2,
 311                         STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER);
 312            push_ucs2(NULL, dom_u, domain_n, (domain_l+1)*2,
 313                         STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER); */
 314
 315         /* BB user and domain may need to be uppercased */
 316         user_l = cifs_strtoUCS(user_u, user_n, 511, nls_codepage);
 317         domain_l = cifs_strtoUCS(dom_u, domain_n, 511, nls_codepage);
 318
 319         user_l++;               /* trailing null */
 320         domain_l++;
 321
 322         hmac_md5_init_limK_to_64(owf, 16, &ctx);
 323         hmac_md5_update((const unsigned char *) user_u, user_l * 2, &ctx);
 324         hmac_md5_update((const unsigned char *) dom_u, domain_l * 2, &ctx);
 325         hmac_md5_final(kr_buf, &ctx);
 326
 327         kfree(user_u);
 328 }
 329 #endif
 330
 331 /* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
 332 #if 0 /* currently unused */
 333 static void
 334 NTLMSSPOWFencrypt(unsigned char passwd[8],
 335                   unsigned char *ntlmchalresp, unsigned char p24[24])
 336 {
 337         unsigned char p21[21];
 338
 339         memset(p21, '\0', 21);
 340         memcpy(p21, passwd, 8);
 341         memset(p21 + 8, 0xbd, 8);
 342
 343         E_P24(p21, ntlmchalresp, p24);
 344 }
 345 #endif
 346
 347 /* Does the NT MD4 hash then des encryption. */
 348 int
 349 SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24)
 350 {
 351         int rc;
 352         unsigned char p16[16], p21[21];
 353
 354         memset(p16, '\0', 16);
 355         memset(p21, '\0', 21);
 356
 357         rc = E_md4hash(passwd, p16);
 358         if (rc) {
 359                 cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
 360                 return rc;
 361         }
 362         memcpy(p21, p16, 16);
 363         rc = E_P24(p21, c8, p24);
 364         return rc;
 365 }
 366
 367
 368 /* Does the md5 encryption from the NT hash for NTLMv2. */
 369 /* These routines will be needed later */
 370 #if 0
 371 static void
 372 SMBOWFencrypt_ntv2(const unsigned char kr[16],
 373                    const struct data_blob *srv_chal,
 374                    const struct data_blob *cli_chal, unsigned char resp_buf[16])
 375 {
 376         struct HMACMD5Context ctx;
 377
 378         hmac_md5_init_limK_to_64(kr, 16, &ctx);
 379         hmac_md5_update(srv_chal->data, srv_chal->length, &ctx);
 380         hmac_md5_update(cli_chal->data, cli_chal->length, &ctx);
 381         hmac_md5_final(resp_buf, &ctx);
 382 }
 383
 384 static void
 385 SMBsesskeygen_ntv2(const unsigned char kr[16],
 386                    const unsigned char *nt_resp, __u8 sess_key[16])
 387 {
 388         struct HMACMD5Context ctx;
 389
 390         hmac_md5_init_limK_to_64(kr, 16, &ctx);
 391         hmac_md5_update(nt_resp, 16, &ctx);
 392         hmac_md5_final((unsigned char *) sess_key, &ctx);
 393 }
 394
 395 static void
 396 SMBsesskeygen_ntv1(const unsigned char kr[16],
 397                    const unsigned char *nt_resp, __u8 sess_key[16])
 398 {
 399         mdfour((unsigned char *) sess_key, (unsigned char *) kr, 16);
 400 }
 401 #endif