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