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 /* produce a md4 message digest from data of length n bytes */
  51 int
  52 mdfour(unsigned char *md4_hash, unsigned char *link_str, int link_len)
  53 {
  54         int rc;
  55         unsigned int size;
  56         struct crypto_shash *md4;
  57         struct sdesc *sdescmd4;
  58
  59         md4 = crypto_alloc_shash("md4", 0, 0);
  60         if (IS_ERR(md4)) {
  61                 cERROR(1, "%s: Crypto md4 allocation error %d\n", __func__, rc);
  62                 return PTR_ERR(md4);
  63         }
  64         size = sizeof(struct shash_desc) + crypto_shash_descsize(md4);
  65         sdescmd4 = kmalloc(size, GFP_KERNEL);
  66         if (!sdescmd4) {
  67                 rc = -ENOMEM;
  68                 cERROR(1, "%s: Memory allocation failure\n", __func__);
  69                 goto mdfour_err;
  70         }
  71         sdescmd4->shash.tfm = md4;
  72         sdescmd4->shash.flags = 0x0;
  73
  74         rc = crypto_shash_init(&sdescmd4->shash);
  75         if (rc) {
  76                 cERROR(1, "%s: Could not init md4 shash\n", __func__);
  77                 goto mdfour_err;
  78         }
  79         crypto_shash_update(&sdescmd4->shash, link_str, link_len);
  80         rc = crypto_shash_final(&sdescmd4->shash, md4_hash);
  81
  82 mdfour_err:
  83         crypto_free_shash(md4);
  84         kfree(sdescmd4);
  85
  86         return rc;
  87 }
  88
  89 /* Does the des encryption from the NT or LM MD4 hash. */
  90 static void
  91 SMBOWFencrypt(unsigned char passwd[16], const unsigned char *c8,
  92               unsigned char p24[24])
  93 {
  94         unsigned char p21[21];
  95
  96         memset(p21, '\0', 21);
  97
  98         memcpy(p21, passwd, 16);
  99         E_P24(p21, c8, p24);
 100 }
 101
 102 /*
 103    This implements the X/Open SMB password encryption
 104    It takes a password, a 8 byte "crypt key" and puts 24 bytes of
 105    encrypted password into p24 */
 106 /* Note that password must be uppercased and null terminated */
 107 void
 108 SMBencrypt(unsigned char *passwd, const unsigned char *c8, unsigned char *p24)
 109 {
 110         unsigned char p14[15], p21[21];
 111
 112         memset(p21, '\0', 21);
 113         memset(p14, '\0', 14);
 114         strncpy((char *) p14, (char *) passwd, 14);
 115
 116 /*      strupper((char *)p14); *//* BB at least uppercase the easy range */
 117         E_P16(p14, p21);
 118
 119         SMBOWFencrypt(p21, c8, p24);
 120
 121         memset(p14, 0, 15);
 122         memset(p21, 0, 21);
 123 }
 124
 125 /* Routines for Windows NT MD4 Hash functions. */
 126 static int
 127 _my_wcslen(__u16 *str)
 128 {
 129         int len = 0;
 130         while (*str++ != 0)
 131                 len++;
 132         return len;
 133 }
 134
 135 /*
 136  * Convert a string into an NT UNICODE string.
 137  * Note that regardless of processor type
 138  * this must be in intel (little-endian)
 139  * format.
 140  */
 141
 142 static int
 143 _my_mbstowcs(__u16 *dst, const unsigned char *src, int len)
 144 {       /* BB not a very good conversion routine - change/fix */
 145         int i;
 146         __u16 val;
 147
 148         for (i = 0; i < len; i++) {
 149                 val = *src;
 150                 SSVAL(dst, 0, val);
 151                 dst++;
 152                 src++;
 153                 if (val == 0)
 154                         break;
 155         }
 156         return i;
 157 }
 158
 159 /*
 160  * Creates the MD4 Hash of the users password in NT UNICODE.
 161  */
 162
 163 int
 164 E_md4hash(const unsigned char *passwd, unsigned char *p16)
 165 {
 166         int rc;
 167         int len;
 168         __u16 wpwd[129];
 169
 170         /* Password cannot be longer than 128 characters */
 171         if (passwd) {
 172                 len = strlen((char *) passwd);
 173                 if (len > 128)
 174                         len = 128;
 175
 176                 /* Password must be converted to NT unicode */
 177                 _my_mbstowcs(wpwd, passwd, len);
 178         } else
 179                 len = 0;
 180
 181         wpwd[len] = 0;  /* Ensure string is null terminated */
 182         /* Calculate length in bytes */
 183         len = _my_wcslen(wpwd) * sizeof(__u16);
 184
 185         rc = mdfour(p16, (unsigned char *) wpwd, len);
 186         memset(wpwd, 0, 129 * 2);
 187
 188         return rc;
 189 }
 190
 191 #if 0 /* currently unused */
 192 /* Does both the NT and LM owfs of a user's password */
 193 static void
 194 nt_lm_owf_gen(char *pwd, unsigned char nt_p16[16], unsigned char p16[16])
 195 {
 196         char passwd[514];
 197
 198         memset(passwd, '\0', 514);
 199         if (strlen(pwd) < 513)
 200                 strcpy(passwd, pwd);
 201         else
 202                 memcpy(passwd, pwd, 512);
 203         /* Calculate the MD4 hash (NT compatible) of the password */
 204         memset(nt_p16, '\0', 16);
 205         E_md4hash(passwd, nt_p16);
 206
 207         /* Mangle the passwords into Lanman format */
 208         passwd[14] = '\0';
 209 /*      strupper(passwd); */
 210
 211         /* Calculate the SMB (lanman) hash functions of the password */
 212
 213         memset(p16, '\0', 16);
 214         E_P16((unsigned char *) passwd, (unsigned char *) p16);
 215
 216         /* clear out local copy of user's password (just being paranoid). */
 217         memset(passwd, '\0', sizeof(passwd));
 218 }
 219 #endif
 220
 221 /* Does the NTLMv2 owfs of a user's password */
 222 #if 0  /* function not needed yet - but will be soon */
 223 static void
 224 ntv2_owf_gen(const unsigned char owf[16], const char *user_n,
 225                 const char *domain_n, unsigned char kr_buf[16],
 226                 const struct nls_table *nls_codepage)
 227 {
 228         wchar_t *user_u;
 229         wchar_t *dom_u;
 230         int user_l, domain_l;
 231         struct HMACMD5Context ctx;
 232
 233         /* might as well do one alloc to hold both (user_u and dom_u) */
 234         user_u = kmalloc(2048 * sizeof(wchar_t), GFP_KERNEL);
 235         if (user_u == NULL)
 236                 return;
 237         dom_u = user_u + 1024;
 238
 239         /* push_ucs2(NULL, user_u, user_n, (user_l+1)*2,
 240                         STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER);
 241            push_ucs2(NULL, dom_u, domain_n, (domain_l+1)*2,
 242                         STR_UNICODE|STR_NOALIGN|STR_TERMINATE|STR_UPPER); */
 243
 244         /* BB user and domain may need to be uppercased */
 245         user_l = cifs_strtoUCS(user_u, user_n, 511, nls_codepage);
 246         domain_l = cifs_strtoUCS(dom_u, domain_n, 511, nls_codepage);
 247
 248         user_l++;               /* trailing null */
 249         domain_l++;
 250
 251         hmac_md5_init_limK_to_64(owf, 16, &ctx);
 252         hmac_md5_update((const unsigned char *) user_u, user_l * 2, &ctx);
 253         hmac_md5_update((const unsigned char *) dom_u, domain_l * 2, &ctx);
 254         hmac_md5_final(kr_buf, &ctx);
 255
 256         kfree(user_u);
 257 }
 258 #endif
 259
 260 /* Does the des encryption from the FIRST 8 BYTES of the NT or LM MD4 hash. */
 261 #if 0 /* currently unused */
 262 static void
 263 NTLMSSPOWFencrypt(unsigned char passwd[8],
 264                   unsigned char *ntlmchalresp, unsigned char p24[24])
 265 {
 266         unsigned char p21[21];
 267
 268         memset(p21, '\0', 21);
 269         memcpy(p21, passwd, 8);
 270         memset(p21 + 8, 0xbd, 8);
 271
 272         E_P24(p21, ntlmchalresp, p24);
 273 }
 274 #endif
 275
 276 /* Does the NT MD4 hash then des encryption. */
 277 int
 278 SMBNTencrypt(unsigned char *passwd, unsigned char *c8, unsigned char *p24)
 279 {
 280         int rc;
 281         unsigned char p21[21];
 282
 283         memset(p21, '\0', 21);
 284
 285         rc = E_md4hash(passwd, p21);
 286         if (rc) {
 287                 cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
 288                 return rc;
 289         }
 290         SMBOWFencrypt(p21, c8, p24);
 291         return rc;
 292 }
 293
 294
 295 /* Does the md5 encryption from the NT hash for NTLMv2. */
 296 /* These routines will be needed later */
 297 #if 0
 298 static void
 299 SMBOWFencrypt_ntv2(const unsigned char kr[16],
 300                    const struct data_blob *srv_chal,
 301                    const struct data_blob *cli_chal, unsigned char resp_buf[16])
 302 {
 303         struct HMACMD5Context ctx;
 304
 305         hmac_md5_init_limK_to_64(kr, 16, &ctx);
 306         hmac_md5_update(srv_chal->data, srv_chal->length, &ctx);
 307         hmac_md5_update(cli_chal->data, cli_chal->length, &ctx);
 308         hmac_md5_final(resp_buf, &ctx);
 309 }
 310
 311 static void
 312 SMBsesskeygen_ntv2(const unsigned char kr[16],
 313                    const unsigned char *nt_resp, __u8 sess_key[16])
 314 {
 315         struct HMACMD5Context ctx;
 316
 317         hmac_md5_init_limK_to_64(kr, 16, &ctx);
 318         hmac_md5_update(nt_resp, 16, &ctx);
 319         hmac_md5_final((unsigned char *) sess_key, &ctx);
 320 }
 321
 322 static void
 323 SMBsesskeygen_ntv1(const unsigned char kr[16],
 324                    const unsigned char *nt_resp, __u8 sess_key[16])
 325 {
 326         mdfour((unsigned char *) sess_key, (unsigned char *) kr, 16);
 327 }
 328 #endif