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                 crypto_free_blkcipher(tfm_des);
  96                 goto smbhash_err;
  97         }
  98
  99 smbhash_err:
 100         return rc;
 101 }
 102
 103 static int
 104 E_P16(unsigned char *p14, unsigned char *p16)
 105 {
 106         int rc;
 107         unsigned char sp8[8] =
 108             { 0x4b, 0x47, 0x53, 0x21, 0x40, 0x23, 0x24, 0x25 };
 109
 110         rc = smbhash(p16, sp8, p14);
 111         if (rc)
 112                 return rc;
 113         rc = smbhash(p16 + 8, sp8, p14 + 7);
 114         return rc;
 115 }
 116
 117 static int
 118 E_P24(unsigned char *p21, const unsigned char *c8, unsigned char *p24)
 119 {
 120         int rc;
 121
 122         rc = smbhash(p24, c8, p21);
 123         if (rc)
 124                 return rc;
 125         rc = smbhash(p24 + 8, c8, p21 + 7);
 126         if (rc)
 127                 return rc;
 128         rc = smbhash(p24 + 16, c8, p21 + 14);
 129         return rc;
 130 }
 131
 132 /* produce a md4 message digest from data of length n bytes */
 133 int
 134 mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
 135 {
 136         int rc;
 137         unsigned int size;
 138         struct crypto_shash *md4;
 139         struct sdesc *sdescmd4;
 140
 141         md4 = crypto_alloc_shash("md4", 0, 0);
 142         if (IS_ERR(md4)) {
 143                 rc = PTR_ERR(md4);
 144                 cERROR(1, "%s: Crypto md4 allocation error %d\n", __func__, rc);
 145                 return rc;
 146         }
 147         size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
 148         sdescmd4 = kmalloc(size, GFP_KERNEL);
 149         if (!sdescmd4) {
 150                 rc = -ENOMEM;
 151                 cERROR(1, "%s: Memory allocation failure\n", __func__);
 152                 goto mdfour_err;
 153         }
 154         sdescmd4->shash.tfm = md4;
 155         sdescmd4->shash.flags = 0x0;
 156
 157         rc = crypto_shash_init(&sdescmd4->shash);
 158         if (rc) {
 159                 cERROR(1, "%s: Could not init md4 shash\n", __func__);
 160                 goto mdfour_err;
 161         }
 162         crypto_shash_update(&sdescmd4->shash, link_str, link_len);
 163         rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
 164
 165 mdfour_err:
 166         crypto_free_shash(md4);
 167         kfree(sdescmd4);
 168
 169         return rc;
 170 }
 171
 172 /*
 173    This implements the X/Open SMB password encryption
 174    It takes a password, a 8 byte "crypt key" and puts 24 bytes of
 175    encrypted password into p24 */
 176 /* Note that password must be uppercased and null terminated */
 177 int
 178 SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
 179 {
 180         int rc;
 181         unsigned char p14[14], p16[16], p21[21];
 182
 183         memset(p14, '\0', 14);
 184         memset(p16, '\0', 16);
 185         memset(p21, '\0', 21);
 186
 187         memcpy(p14, passwd, 14);
 188         rc = E_P16(p14, p16);
 189         if (rc)
 190                 return rc;
 191
 192         memcpy(p21, p16, 16);
 193         rc = E_P24(p21, c8, p24);
 194
 195         return rc;
 196 }
 197
 198 /* Routines for Windows NT MD4 Hash functions. */
 199 static int
 200 _my_wcslen(__u16 *str)
 201 {
 202         int len = 0;
 203         while (*str++ != 0)
 204                 len++;
 205         return len;
 206 }
 207
 208 /*
 209  * Convert a string into an NT UNICODE string.
 210  * Note that regardless of processor type
 211  * this must be in intel (little-endian)
 212  * format.
 213  */
 214
 215 static int
 216 _my_mbstowcs(__u16 *dst, const unsigned char *src, int len)
 217 {       /* BB not a very good conversion routine - change/fix */
 218         int i;
 219         __u16 val;
 220
 221         for (i = 0; i < len; i++) {
 222                 val = *src;
 223                 SSVAL(dst, 0, val);
 224                 dst++;
 225                 src++;
 226                 if (val == 0)
 227                         break;
 228         }
 229         return i;
 230 }
 231
 232 /*
 233  * Creates the MD4 Hash of the users password in NT UNICODE.
 234  */
 235
 236 int
 237 E_md4hash(const unsigned char *passwd, unsigned char *p16)
 238 {
 239         int rc;
 240         int len;
 241         __u16 wpwd[129];
 242
 243         /* Password cannot be longer than 128 characters */
 244         if (passwd) {
 245                 len = strlen((char *) passwd);
 246                 if (len > 128)
 247                         len = 128;
 248
 249                 /* Password must be converted to NT unicode */
 250                 _my_mbstowcs(wpwd, passwd, len);
 251         } else
 252                 len = 0;
 253
 254         wpwd[len] = 0;  /* Ensure string is null terminated */
 255         /* Calculate length in bytes */
 256         len = _my_wcslen(wpwd) * sizeof(__u16);
 257
 258         rc = mdfour(p16, (unsigned char *) wpwd, len);
 259         memset(wpwd, 0, 129 * 2);
 260
 261         return rc;
 262 }
 263
 264 #if 0 /* currently unused */
 265 /* Does both the NT and LM owfs of a user's password */
 266 static void
 267 nt_lm_owf_gen(char *pwd, unsigned char nt_p16[16], unsigned char p16[16])
 268 {
 269         char passwd[514];
 270
 271         memset(passwd, '\0', 514);
 272         if (strlen(pwd) < 513)
 273                 strcpy(passwd, pwd);
 274         else
 275                 memcpy(passwd, pwd, 512);
 276         /* Calculate the MD4 hash (NT compatible) of the password */
 277         memset(nt_p16, '\0', 16);
 278         E_md4hash(passwd, nt_p16);
 279
 280         /* Mangle the passwords into Lanman format */
 281         passwd[14] = '\0';
 282 /*      strupper(passwd); */
 283
 284         /* Calculate the SMB (lanman) hash functions of the password */
 285
 286         memset(p16, '\0', 16);
 287         E_P16((unsigned char *) passwd, (unsigned char *) p16);
 288
 289         /* clear out local copy of user's password (just being paranoid). */
 290         memset(passwd, '\0', sizeof(passwd));
 291 }
 292 #endif
 293
 294 /* Does the NTLMv2 owfs of a user's password */
 295 #if 0  /* function not needed yet - but will be soon */
 296 static void
 297 ntv2_owf_gen(const unsigned char owf[16], const char *user_n,
 298                 const char *domain_n, unsigned char kr_buf[16],
 299                 const struct nls_table *nls_codepage)
 300 {
 301         wchar_t *user_u;
 302         wchar_t *dom_u;
 303         int user_l, domain_l;
 304         struct HMACMD5Context ctx;
 305
 306         /* might as well do one alloc to hold both (user_u and dom_u) */
 307         user_u = kmalloc(2048 * sizeof(wchar_t), GFP_KERNEL);
 308         if (user_u == NULL)
 309                 return;
 310         dom_u = user_u + 1024;
 311
 312         /* push_ucs2(NULL, user_u, user_n, (user_l+1)*2,
 313                         STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER);
 314            push_ucs2(NULL, dom_u, domain_n, (domain_l+1)*2,
 315                         STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER); */
 316
 317         /* BB user and domain may need to be uppercased */
 318         user_l = cifs_strtoUCS(user_u, user_n, 511, nls_codepage);
 319         domain_l = cifs_strtoUCS(dom_u, domain_n, 511, nls_codepage);
 320
 321         user_l++;               /* trailing null */
 322         domain_l++;
 323
 324         hmac_md5_init_limK_to_64(owf, 16, &ctx);
 325         hmac_md5_update((const unsigned char *) user_u, user_l * 2, &ctx);
 326         hmac_md5_update((const unsigned char *) dom_u, domain_l * 2, &ctx);
 327         hmac_md5_final(kr_buf, &ctx);
 328
 329         kfree(user_u);
 330 }
 331 #endif
 332
 333 /* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
 334 #if 0 /* currently unused */
 335 static void
 336 NTLMSSPOWFencrypt(unsigned char passwd[8],
 337                   unsigned char *ntlmchalresp, unsigned char p24[24])
 338 {
 339         unsigned char p21[21];
 340
 341         memset(p21, '\0', 21);
 342         memcpy(p21, passwd, 8);
 343         memset(p21 + 8, 0xbd, 8);
 344
 345         E_P24(p21, ntlmchalresp, p24);
 346 }
 347 #endif
 348
 349 /* Does the NT MD4 hash then des encryption. */
 350 int
 351 SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24)
 352 {
 353         int rc;
 354         unsigned char p16[16], p21[21];
 355
 356         memset(p16, '\0', 16);
 357         memset(p21, '\0', 21);
 358
 359         rc = E_md4hash(passwd, p16);
 360         if (rc) {
 361                 cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
 362                 return rc;
 363         }
 364         memcpy(p21, p16, 16);
 365         rc = E_P24(p21, c8, p24);
 366         return rc;
 367 }
 368
 369
 370 /* Does the md5 encryption from the NT hash for NTLMv2. */
 371 /* These routines will be needed later */
 372 #if 0
 373 static void
 374 SMBOWFencrypt_ntv2(const unsigned char kr[16],
 375                    const struct data_blob *srv_chal,
 376                    const struct data_blob *cli_chal, unsigned char resp_buf[16])
 377 {
 378         struct HMACMD5Context ctx;
 379
 380         hmac_md5_init_limK_to_64(kr, 16, &ctx);
 381         hmac_md5_update(srv_chal->data, srv_chal->length, &ctx);
 382         hmac_md5_update(cli_chal->data, cli_chal->length, &ctx);
 383         hmac_md5_final(resp_buf, &ctx);
 384 }
 385
 386 static void
 387 SMBsesskeygen_ntv2(const unsigned char kr[16],
 388                    const unsigned char *nt_resp, __u8 sess_key[16])
 389 {
 390         struct HMACMD5Context ctx;
 391
 392         hmac_md5_init_limK_to_64(kr, 16, &ctx);
 393         hmac_md5_update(nt_resp, 16, &ctx);
 394         hmac_md5_final((unsigned char *) sess_key, &ctx);
 395 }
 396
 397 static void
 398 SMBsesskeygen_ntv1(const unsigned char kr[16],
 399                    const unsigned char *nt_resp, __u8 sess_key[16])
 400 {
 401         mdfour((unsigned char *) sess_key, (unsigned char *) kr, 16);
 402 }
 403 #endif