blob: 5a0ee7f2af062a68fdec065c43099274486c1b2d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * fs/cifs/cifsencrypt.c
3 *
Steve French12b3b8f2006-02-09 21:12:47 +00004 * Copyright (C) International Business Machines Corp., 2005,2006
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 * This library is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU Lesser General Public License as published
9 * by the Free Software Foundation; either version 2.1 of the License, or
10 * (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
15 * the GNU Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22#include <linux/fs.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090023#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include "cifspdu.h"
Steve Frenchffdd6e42007-06-24 21:15:44 +000025#include "cifsglob.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include "cifs_debug.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include "cifs_unicode.h"
28#include "cifsproto.h"
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -050029#include "ntlmssp.h"
Steve French7c7b25b2006-06-01 19:20:10 +000030#include <linux/ctype.h>
Steve French6d027cf2006-06-05 16:26:05 +000031#include <linux/random.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032
Jeff Layton157c2492011-04-02 07:34:30 -040033/*
34 * Calculate and return the CIFS signature based on the mac key and SMB PDU.
35 * The 16 byte signature must be allocated by the caller. Note we only use the
36 * 1st eight bytes and that the smb header signature field on input contains
37 * the sequence number before this function is called. Also, this function
38 * should be called with the server->srv_mutex held.
39 */
Steve Frenchffdd6e42007-06-24 21:15:44 +000040static int cifs_calculate_signature(const struct smb_hdr *cifs_pdu,
Shirish Pargaonkar21e73392010-10-21 06:42:55 -050041 struct TCP_Server_Info *server, char *signature)
Linus Torvalds1da177e2005-04-16 15:20:36 -070042{
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -050043 int rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -070044
Shirish Pargaonkar21e73392010-10-21 06:42:55 -050045 if (cifs_pdu == NULL || signature == NULL || server == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -070046 return -EINVAL;
47
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -050048 if (!server->secmech.sdescmd5) {
49 cERROR(1, "%s: Can't generate signature\n", __func__);
50 return -1;
51 }
Steve Frenchb609f062007-07-09 07:55:14 +000052
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -050053 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
54 if (rc) {
55 cERROR(1, "%s: Oould not init md5\n", __func__);
56 return rc;
57 }
58
59 crypto_shash_update(&server->secmech.sdescmd5->shash,
60 server->session_key.response, server->session_key.len);
61
62 crypto_shash_update(&server->secmech.sdescmd5->shash,
Steve Frenchbe8e3b02011-04-29 05:40:20 +000063 cifs_pdu->Protocol, be32_to_cpu(cifs_pdu->smb_buf_length));
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -050064
65 rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
66
Steve French56234e22010-09-08 20:57:05 +000067 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070068}
69
Jeff Laytona0f8b4f2011-01-07 11:30:28 -050070/* must be called with server->srv_mutex held */
Steve Frenchffdd6e42007-06-24 21:15:44 +000071int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
72 __u32 *pexpected_response_sequence_number)
Linus Torvalds1da177e2005-04-16 15:20:36 -070073{
74 int rc = 0;
75 char smb_signature[20];
76
Steve Frenchffdd6e42007-06-24 21:15:44 +000077 if ((cifs_pdu == NULL) || (server == NULL))
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 return -EINVAL;
79
Steve Frenchffdd6e42007-06-24 21:15:44 +000080 if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 return rc;
82
Steve French50c2f752007-07-13 00:33:32 +000083 cifs_pdu->Signature.Sequence.SequenceNumber =
84 cpu_to_le32(server->sequence_number);
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 cifs_pdu->Signature.Sequence.Reserved = 0;
Steve French50c2f752007-07-13 00:33:32 +000086
Steve Frenchad009ac2005-04-28 22:41:05 -070087 *pexpected_response_sequence_number = server->sequence_number++;
88 server->sequence_number++;
Linus Torvalds1da177e2005-04-16 15:20:36 -070089
Shirish Pargaonkar21e73392010-10-21 06:42:55 -050090 rc = cifs_calculate_signature(cifs_pdu, server, smb_signature);
Steve Frenchffdd6e42007-06-24 21:15:44 +000091 if (rc)
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
93 else
94 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
95
96 return rc;
97}
98
Steve Frenchffdd6e42007-06-24 21:15:44 +000099static int cifs_calc_signature2(const struct kvec *iov, int n_vec,
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500100 struct TCP_Server_Info *server, char *signature)
Steve French84afc292005-12-02 13:32:45 -0800101{
Steve Frenche9917a02006-03-31 21:22:00 +0000102 int i;
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500103 int rc;
Steve French84afc292005-12-02 13:32:45 -0800104
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500105 if (iov == NULL || signature == NULL || server == NULL)
Steve Frenche9917a02006-03-31 21:22:00 +0000106 return -EINVAL;
Steve French84afc292005-12-02 13:32:45 -0800107
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500108 if (!server->secmech.sdescmd5) {
109 cERROR(1, "%s: Can't generate signature\n", __func__);
110 return -1;
111 }
112
113 rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
114 if (rc) {
115 cERROR(1, "%s: Oould not init md5\n", __func__);
116 return rc;
117 }
118
119 crypto_shash_update(&server->secmech.sdescmd5->shash,
120 server->session_key.response, server->session_key.len);
121
Steve French50c2f752007-07-13 00:33:32 +0000122 for (i = 0; i < n_vec; i++) {
Jeff Layton745542e2007-11-03 04:34:04 +0000123 if (iov[i].iov_len == 0)
124 continue;
Steve Frenchffdd6e42007-06-24 21:15:44 +0000125 if (iov[i].iov_base == NULL) {
Steve French56234e22010-09-08 20:57:05 +0000126 cERROR(1, "null iovec entry");
Steve Frenche9917a02006-03-31 21:22:00 +0000127 return -EIO;
Jeff Layton745542e2007-11-03 04:34:04 +0000128 }
Steve Frenchffdd6e42007-06-24 21:15:44 +0000129 /* The first entry includes a length field (which does not get
Steve Frenche9917a02006-03-31 21:22:00 +0000130 signed that occupies the first 4 bytes before the header */
Steve Frenchffdd6e42007-06-24 21:15:44 +0000131 if (i == 0) {
Steve French63d25832007-11-05 21:46:10 +0000132 if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
Steve Frenche9917a02006-03-31 21:22:00 +0000133 break; /* nothing to sign or corrupt header */
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500134 crypto_shash_update(&server->secmech.sdescmd5->shash,
135 iov[i].iov_base + 4, iov[i].iov_len - 4);
Steve Frenche9917a02006-03-31 21:22:00 +0000136 } else
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500137 crypto_shash_update(&server->secmech.sdescmd5->shash,
138 iov[i].iov_base, iov[i].iov_len);
Steve Frenche9917a02006-03-31 21:22:00 +0000139 }
Steve French84afc292005-12-02 13:32:45 -0800140
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500141 rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
Steve French84afc292005-12-02 13:32:45 -0800142
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500143 return rc;
Steve French84afc292005-12-02 13:32:45 -0800144}
145
Jeff Laytona0f8b4f2011-01-07 11:30:28 -0500146/* must be called with server->srv_mutex held */
Steve Frenchffdd6e42007-06-24 21:15:44 +0000147int cifs_sign_smb2(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
Steve French63d25832007-11-05 21:46:10 +0000148 __u32 *pexpected_response_sequence_number)
Steve French84afc292005-12-02 13:32:45 -0800149{
150 int rc = 0;
151 char smb_signature[20];
Steve Frenchffdd6e42007-06-24 21:15:44 +0000152 struct smb_hdr *cifs_pdu = iov[0].iov_base;
Steve French84afc292005-12-02 13:32:45 -0800153
Steve Frenchffdd6e42007-06-24 21:15:44 +0000154 if ((cifs_pdu == NULL) || (server == NULL))
Steve French84afc292005-12-02 13:32:45 -0800155 return -EINVAL;
156
Steve Frenchffdd6e42007-06-24 21:15:44 +0000157 if ((cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) == 0)
Steve French84afc292005-12-02 13:32:45 -0800158 return rc;
159
Steve Frenchffdd6e42007-06-24 21:15:44 +0000160 cifs_pdu->Signature.Sequence.SequenceNumber =
Steve French84afc292005-12-02 13:32:45 -0800161 cpu_to_le32(server->sequence_number);
Steve Frenchffdd6e42007-06-24 21:15:44 +0000162 cifs_pdu->Signature.Sequence.Reserved = 0;
Steve French84afc292005-12-02 13:32:45 -0800163
Steve Frenchffdd6e42007-06-24 21:15:44 +0000164 *pexpected_response_sequence_number = server->sequence_number++;
165 server->sequence_number++;
Steve French84afc292005-12-02 13:32:45 -0800166
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500167 rc = cifs_calc_signature2(iov, n_vec, server, smb_signature);
Steve Frenchffdd6e42007-06-24 21:15:44 +0000168 if (rc)
169 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
170 else
171 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
Steve French84afc292005-12-02 13:32:45 -0800172
Steve Frenchffdd6e42007-06-24 21:15:44 +0000173 return rc;
Steve French84afc292005-12-02 13:32:45 -0800174}
175
Steve Frenchb609f062007-07-09 07:55:14 +0000176int cifs_verify_signature(struct smb_hdr *cifs_pdu,
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500177 struct TCP_Server_Info *server,
Steve Frenchffdd6e42007-06-24 21:15:44 +0000178 __u32 expected_sequence_number)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179{
Steve Frenchc8e56f12010-09-08 21:10:58 +0000180 unsigned int rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 char server_response_sig[8];
182 char what_we_think_sig_should_be[20];
183
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500184 if (cifs_pdu == NULL || server == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 return -EINVAL;
186
Jeff Layton9c4843e2011-06-06 15:40:23 -0400187 if (!server->session_estab)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 return 0;
189
190 if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
Steve French50c2f752007-07-13 00:33:32 +0000191 struct smb_com_lock_req *pSMB =
Steve Frenchffdd6e42007-06-24 21:15:44 +0000192 (struct smb_com_lock_req *)cifs_pdu;
193 if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 return 0;
195 }
196
Steve French50c2f752007-07-13 00:33:32 +0000197 /* BB what if signatures are supposed to be on for session but
198 server does not send one? BB */
199
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 /* Do not need to verify session setups with signature "BSRSPYL " */
Steve French50c2f752007-07-13 00:33:32 +0000201 if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
Joe Perchesb6b38f72010-04-21 03:50:45 +0000202 cFYI(1, "dummy signature received for smb command 0x%x",
203 cifs_pdu->Command);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
205 /* save off the origiginal signature so we can modify the smb and check
206 its signature against what the server sent */
Steve French50c2f752007-07-13 00:33:32 +0000207 memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208
Steve French50c2f752007-07-13 00:33:32 +0000209 cifs_pdu->Signature.Sequence.SequenceNumber =
210 cpu_to_le32(expected_sequence_number);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 cifs_pdu->Signature.Sequence.Reserved = 0;
212
Jeff Layton157c2492011-04-02 07:34:30 -0400213 mutex_lock(&server->srv_mutex);
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500214 rc = cifs_calculate_signature(cifs_pdu, server,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 what_we_think_sig_should_be);
Jeff Layton157c2492011-04-02 07:34:30 -0400216 mutex_unlock(&server->srv_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217
Steve French50c2f752007-07-13 00:33:32 +0000218 if (rc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 return rc;
220
Steve French50c2f752007-07-13 00:33:32 +0000221/* cifs_dump_mem("what we think it should be: ",
222 what_we_think_sig_should_be, 16); */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223
Steve French50c2f752007-07-13 00:33:32 +0000224 if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 return -EACCES;
226 else
227 return 0;
228
229}
230
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500231/* first calculate 24 bytes ntlm response and then 16 byte session key */
Steve French96daf2b2011-05-27 04:34:02 +0000232int setup_ntlm_response(struct cifs_ses *ses)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233{
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600234 int rc = 0;
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500235 unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
236 char temp_key[CIFS_SESS_KEY_SIZE];
237
238 if (!ses)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 return -EINVAL;
240
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500241 ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
242 if (!ses->auth_key.response) {
243 cERROR(1, "NTLM can't allocate (%u bytes) memory", temp_len);
244 return -ENOMEM;
245 }
246 ses->auth_key.len = temp_len;
247
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600248 rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500249 ses->auth_key.response + CIFS_SESS_KEY_SIZE);
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600250 if (rc) {
251 cFYI(1, "%s Can't generate NTLM response, error: %d",
252 __func__, rc);
253 return rc;
254 }
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500255
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600256 rc = E_md4hash(ses->password, temp_key);
257 if (rc) {
258 cFYI(1, "%s Can't generate NT hash, error: %d", __func__, rc);
259 return rc;
260 }
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500261
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600262 rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
263 if (rc)
264 cFYI(1, "%s Can't generate NTLM session key, error: %d",
265 __func__, rc);
266
267 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268}
269
Steve French7c7b25b2006-06-01 19:20:10 +0000270#ifdef CONFIG_CIFS_WEAK_PW_HASH
Steve French43988d72011-04-19 18:23:31 +0000271int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
Jeff Layton4e53a3f2008-12-05 20:41:21 -0500272 char *lnm_session_key)
Steve French7c7b25b2006-06-01 19:20:10 +0000273{
274 int i;
Steve French43988d72011-04-19 18:23:31 +0000275 int rc;
Steve French7c7b25b2006-06-01 19:20:10 +0000276 char password_with_pad[CIFS_ENCPWD_SIZE];
277
278 memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
Jeff Layton4e53a3f2008-12-05 20:41:21 -0500279 if (password)
280 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
Steve French7c7b25b2006-06-01 19:20:10 +0000281
Jeff Layton04912d62010-04-24 07:57:45 -0400282 if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
Jeff Layton4e53a3f2008-12-05 20:41:21 -0500283 memset(lnm_session_key, 0, CIFS_SESS_KEY_SIZE);
284 memcpy(lnm_session_key, password_with_pad,
285 CIFS_ENCPWD_SIZE);
Steve French43988d72011-04-19 18:23:31 +0000286 return 0;
Jeff Layton4e53a3f2008-12-05 20:41:21 -0500287 }
Steve Frenchbdc4bf6e2006-06-02 22:57:13 +0000288
Steve French7c7b25b2006-06-01 19:20:10 +0000289 /* calculate old style session key */
290 /* calling toupper is less broken than repeatedly
291 calling nls_toupper would be since that will never
292 work for UTF8, but neither handles multibyte code pages
293 but the only alternative would be converting to UCS-16 (Unicode)
294 (using a routine something like UniStrupr) then
295 uppercasing and then converting back from Unicode - which
296 would only worth doing it if we knew it were utf8. Basically
297 utf8 and other multibyte codepages each need their own strupper
298 function since a byte at a time will ont work. */
299
Shirish Pargaonkaref571ca2008-07-24 15:56:05 +0000300 for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
Steve French7c7b25b2006-06-01 19:20:10 +0000301 password_with_pad[i] = toupper(password_with_pad[i]);
Steve French7c7b25b2006-06-01 19:20:10 +0000302
Steve French43988d72011-04-19 18:23:31 +0000303 rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
Jeff Layton4e53a3f2008-12-05 20:41:21 -0500304
Steve French43988d72011-04-19 18:23:31 +0000305 return rc;
Steve French7c7b25b2006-06-01 19:20:10 +0000306}
307#endif /* CIFS_WEAK_PW_HASH */
308
Shirish Pargaonkar9daa42e2010-10-10 13:21:05 -0500309/* Build a proper attribute value/target info pairs blob.
310 * Fill in netbios and dns domain name and workstation name
311 * and client time (total five av pairs and + one end of fields indicator.
312 * Allocate domain name which gets freed when session struct is deallocated.
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500313 */
314static int
Steve French96daf2b2011-05-27 04:34:02 +0000315build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500316{
Shirish Pargaonkar9daa42e2010-10-10 13:21:05 -0500317 unsigned int dlen;
318 unsigned int wlen;
319 unsigned int size = 6 * sizeof(struct ntlmssp2_name);
320 __le64 curtime;
321 char *defdmname = "WORKGROUP";
322 unsigned char *blobptr;
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500323 struct ntlmssp2_name *attrptr;
324
Shirish Pargaonkar9daa42e2010-10-10 13:21:05 -0500325 if (!ses->domainName) {
326 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
327 if (!ses->domainName)
328 return -ENOMEM;
329 }
330
331 dlen = strlen(ses->domainName);
332 wlen = strlen(ses->server->hostname);
333
334 /* The length of this blob is a size which is
335 * six times the size of a structure which holds name/size +
336 * two times the unicode length of a domain name +
337 * two times the unicode length of a server name +
338 * size of a timestamp (which is 8 bytes).
339 */
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500340 ses->auth_key.len = size + 2 * (2 * dlen) + 2 * (2 * wlen) + 8;
341 ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
342 if (!ses->auth_key.response) {
343 ses->auth_key.len = 0;
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500344 cERROR(1, "Challenge target info allocation failure");
345 return -ENOMEM;
346 }
Shirish Pargaonkar9daa42e2010-10-10 13:21:05 -0500347
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500348 blobptr = ses->auth_key.response;
Shirish Pargaonkar9daa42e2010-10-10 13:21:05 -0500349 attrptr = (struct ntlmssp2_name *) blobptr;
350
351 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
352 attrptr->length = cpu_to_le16(2 * dlen);
353 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
354 cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
355
356 blobptr += 2 * dlen;
357 attrptr = (struct ntlmssp2_name *) blobptr;
358
359 attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_COMPUTER_NAME);
360 attrptr->length = cpu_to_le16(2 * wlen);
361 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
362 cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);
363
364 blobptr += 2 * wlen;
365 attrptr = (struct ntlmssp2_name *) blobptr;
366
367 attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_DOMAIN_NAME);
368 attrptr->length = cpu_to_le16(2 * dlen);
369 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
370 cifs_strtoUCS((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
371
372 blobptr += 2 * dlen;
373 attrptr = (struct ntlmssp2_name *) blobptr;
374
375 attrptr->type = cpu_to_le16(NTLMSSP_AV_DNS_COMPUTER_NAME);
376 attrptr->length = cpu_to_le16(2 * wlen);
377 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
378 cifs_strtoUCS((__le16 *)blobptr, ses->server->hostname, wlen, nls_cp);
379
380 blobptr += 2 * wlen;
381 attrptr = (struct ntlmssp2_name *) blobptr;
382
383 attrptr->type = cpu_to_le16(NTLMSSP_AV_TIMESTAMP);
384 attrptr->length = cpu_to_le16(sizeof(__le64));
385 blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
386 curtime = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
387 memcpy(blobptr, &curtime, sizeof(__le64));
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500388
389 return 0;
390}
391
392/* Server has provided av pairs/target info in the type 2 challenge
393 * packet and we have plucked it and stored within smb session.
394 * We parse that blob here to find netbios domain name to be used
395 * as part of ntlmv2 authentication (in Target String), if not already
396 * specified on the command line.
397 * If this function returns without any error but without fetching
398 * domain name, authentication may fail against some server but
399 * may not fail against other (those who are not very particular
400 * about target string i.e. for some, just user name might suffice.
401 */
402static int
Steve French96daf2b2011-05-27 04:34:02 +0000403find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500404{
405 unsigned int attrsize;
406 unsigned int type;
407 unsigned int onesize = sizeof(struct ntlmssp2_name);
408 unsigned char *blobptr;
409 unsigned char *blobend;
410 struct ntlmssp2_name *attrptr;
411
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500412 if (!ses->auth_key.len || !ses->auth_key.response)
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500413 return 0;
414
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500415 blobptr = ses->auth_key.response;
416 blobend = blobptr + ses->auth_key.len;
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500417
418 while (blobptr + onesize < blobend) {
419 attrptr = (struct ntlmssp2_name *) blobptr;
420 type = le16_to_cpu(attrptr->type);
421 if (type == NTLMSSP_AV_EOL)
422 break;
423 blobptr += 2; /* advance attr type */
424 attrsize = le16_to_cpu(attrptr->length);
425 blobptr += 2; /* advance attr size */
426 if (blobptr + attrsize > blobend)
427 break;
428 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
429 if (!attrsize)
430 break;
431 if (!ses->domainName) {
432 ses->domainName =
433 kmalloc(attrsize + 1, GFP_KERNEL);
434 if (!ses->domainName)
435 return -ENOMEM;
436 cifs_from_ucs2(ses->domainName,
437 (__le16 *)blobptr, attrsize, attrsize,
Shirish Pargaonkarf7c54452010-10-26 18:10:24 -0500438 nls_cp, false);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500439 break;
440 }
441 }
442 blobptr += attrsize; /* advance attr value */
443 }
444
445 return 0;
446}
447
Steve French96daf2b2011-05-27 04:34:02 +0000448static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
Steve French50c2f752007-07-13 00:33:32 +0000449 const struct nls_table *nls_cp)
Steve Frencha8ee0342006-06-05 23:34:19 +0000450{
451 int rc = 0;
452 int len;
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500453 char nt_hash[CIFS_NTHASH_SIZE];
Steve French50c2f752007-07-13 00:33:32 +0000454 wchar_t *user;
455 wchar_t *domain;
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500456 wchar_t *server;
Steve Frenchc8e56f12010-09-08 21:10:58 +0000457
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500458 if (!ses->server->secmech.sdeschmacmd5) {
459 cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
460 return -1;
461 }
Steve Frencha8ee0342006-06-05 23:34:19 +0000462
463 /* calculate md4 hash of password */
464 E_md4hash(ses->password, nt_hash);
465
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500466 crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
467 CIFS_NTHASH_SIZE);
468
469 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
470 if (rc) {
471 cERROR(1, "calc_ntlmv2_hash: could not init hmacmd5\n");
472 return rc;
473 }
Steve Frencha8ee0342006-06-05 23:34:19 +0000474
Steve French8727c8a2011-02-25 01:11:56 -0600475 /* convert ses->user_name to unicode and uppercase */
476 len = strlen(ses->user_name);
Steve French1717ffc2006-06-08 05:41:32 +0000477 user = kmalloc(2 + (len * 2), GFP_KERNEL);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500478 if (user == NULL) {
479 cERROR(1, "calc_ntlmv2_hash: user mem alloc failure\n");
480 rc = -ENOMEM;
Steve French1717ffc2006-06-08 05:41:32 +0000481 goto calc_exit_2;
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500482 }
Steve French8727c8a2011-02-25 01:11:56 -0600483 len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp);
Steve French1717ffc2006-06-08 05:41:32 +0000484 UniStrupr(user);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500485
486 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
487 (char *)user, 2 * len);
Steve Frencha8ee0342006-06-05 23:34:19 +0000488
489 /* convert ses->domainName to unicode and uppercase */
Steve French50c2f752007-07-13 00:33:32 +0000490 if (ses->domainName) {
Steve French1717ffc2006-06-08 05:41:32 +0000491 len = strlen(ses->domainName);
Steve Frencha8ee0342006-06-05 23:34:19 +0000492
Steve French50c2f752007-07-13 00:33:32 +0000493 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500494 if (domain == NULL) {
495 cERROR(1, "calc_ntlmv2_hash: domain mem alloc failure");
496 rc = -ENOMEM;
Steve French1717ffc2006-06-08 05:41:32 +0000497 goto calc_exit_1;
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500498 }
Cyril Gorcunov8f2376a2007-10-14 17:58:43 +0000499 len = cifs_strtoUCS((__le16 *)domain, ses->domainName, len,
500 nls_cp);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500501 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
502 (char *)domain, 2 * len);
Steve French1717ffc2006-06-08 05:41:32 +0000503 kfree(domain);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500504 } else if (ses->serverName) {
505 len = strlen(ses->serverName);
506
507 server = kmalloc(2 + (len * 2), GFP_KERNEL);
508 if (server == NULL) {
509 cERROR(1, "calc_ntlmv2_hash: server mem alloc failure");
510 rc = -ENOMEM;
511 goto calc_exit_1;
512 }
513 len = cifs_strtoUCS((__le16 *)server, ses->serverName, len,
514 nls_cp);
515 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
516 (char *)server, 2 * len);
517 kfree(server);
Steve French1717ffc2006-06-08 05:41:32 +0000518 }
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500519
520 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500521 ntlmv2_hash);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500522
Steve French1717ffc2006-06-08 05:41:32 +0000523calc_exit_1:
524 kfree(user);
525calc_exit_2:
Steve Frencha8ee0342006-06-05 23:34:19 +0000526 return rc;
527}
528
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500529static int
Steve French96daf2b2011-05-27 04:34:02 +0000530CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500531{
532 int rc;
533 unsigned int offset = CIFS_SESS_KEY_SIZE + 8;
534
535 if (!ses->server->secmech.sdeschmacmd5) {
536 cERROR(1, "calc_ntlmv2_hash: can't generate ntlmv2 hash\n");
537 return -1;
538 }
539
540 crypto_shash_setkey(ses->server->secmech.hmacmd5,
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500541 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500542
543 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
544 if (rc) {
545 cERROR(1, "CalcNTLMv2_response: could not init hmacmd5");
546 return rc;
547 }
548
Shirish Pargaonkard3ba50b2010-10-27 15:20:36 -0500549 if (ses->server->secType == RawNTLMSSP)
550 memcpy(ses->auth_key.response + offset,
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500551 ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
Shirish Pargaonkard3ba50b2010-10-27 15:20:36 -0500552 else
553 memcpy(ses->auth_key.response + offset,
554 ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500555 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
556 ses->auth_key.response + offset, ses->auth_key.len - offset);
557
558 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
559 ses->auth_key.response + CIFS_SESS_KEY_SIZE);
560
561 return rc;
562}
563
564
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500565int
Steve French96daf2b2011-05-27 04:34:02 +0000566setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
Steve French9fbc5902010-08-20 20:42:26 +0000567{
Steve Frenchc8e56f12010-09-08 21:10:58 +0000568 int rc;
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500569 int baselen;
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500570 unsigned int tilen;
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500571 struct ntlmv2_resp *buf;
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500572 char ntlmv2_hash[16];
573 unsigned char *tiblob = NULL; /* target info blob */
Steve French6d027cf2006-06-05 16:26:05 +0000574
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500575 if (ses->server->secType == RawNTLMSSP) {
576 if (!ses->domainName) {
Shirish Pargaonkarf7c54452010-10-26 18:10:24 -0500577 rc = find_domain_name(ses, nls_cp);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500578 if (rc) {
579 cERROR(1, "error %d finding domain name", rc);
580 goto setup_ntlmv2_rsp_ret;
581 }
582 }
583 } else {
Shirish Pargaonkar9daa42e2010-10-10 13:21:05 -0500584 rc = build_avpair_blob(ses, nls_cp);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500585 if (rc) {
586 cERROR(1, "error %d building av pair blob", rc);
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500587 goto setup_ntlmv2_rsp_ret;
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500588 }
589 }
Steve Frencha8ee0342006-06-05 23:34:19 +0000590
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500591 baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500592 tilen = ses->auth_key.len;
593 tiblob = ses->auth_key.response;
594
595 ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500596 if (!ses->auth_key.response) {
597 rc = ENOMEM;
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500598 ses->auth_key.len = 0;
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500599 cERROR(1, "%s: Can't allocate auth blob", __func__);
600 goto setup_ntlmv2_rsp_ret;
601 }
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500602 ses->auth_key.len += baselen;
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500603
604 buf = (struct ntlmv2_resp *)
605 (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
606 buf->blob_signature = cpu_to_le32(0x00000101);
607 buf->reserved = 0;
608 buf->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
609 get_random_bytes(&buf->client_chal, sizeof(buf->client_chal));
610 buf->reserved2 = 0;
611
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500612 memcpy(ses->auth_key.response + baselen, tiblob, tilen);
Shirish Pargaonkar21e73392010-10-21 06:42:55 -0500613
Shirish Pargaonkarf7c54452010-10-26 18:10:24 -0500614 /* calculate ntlmv2_hash */
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500615 rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500616 if (rc) {
Joe Perchesb6b38f72010-04-21 03:50:45 +0000617 cERROR(1, "could not get v2 hash rc %d", rc);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500618 goto setup_ntlmv2_rsp_ret;
619 }
Shirish Pargaonkarf7c54452010-10-26 18:10:24 -0500620
621 /* calculate first part of the client response (CR1) */
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500622 rc = CalcNTLMv2_response(ses, ntlmv2_hash);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500623 if (rc) {
624 cERROR(1, "Could not calculate CR1 rc: %d", rc);
625 goto setup_ntlmv2_rsp_ret;
626 }
Steve Frenchb609f062007-07-09 07:55:14 +0000627
Shirish Pargaonkar5d0d2882010-10-13 18:15:00 -0500628 /* now calculate the session key for NTLMv2 */
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500629 crypto_shash_setkey(ses->server->secmech.hmacmd5,
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500630 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
Shirish Pargaonkar307fbd32010-10-21 14:25:17 -0500631
632 rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
633 if (rc) {
634 cERROR(1, "%s: Could not init hmacmd5\n", __func__);
635 goto setup_ntlmv2_rsp_ret;
636 }
637
638 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
639 ses->auth_key.response + CIFS_SESS_KEY_SIZE,
640 CIFS_HMAC_MD5_HASH_SIZE);
641
642 rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
643 ses->auth_key.response);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500644
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500645setup_ntlmv2_rsp_ret:
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500646 kfree(tiblob);
Shirish Pargaonkar2b149f12010-09-18 22:02:18 -0500647
648 return rc;
Steve French6d027cf2006-06-05 16:26:05 +0000649}
650
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500651int
Steve French96daf2b2011-05-27 04:34:02 +0000652calc_seckey(struct cifs_ses *ses)
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500653{
654 int rc;
655 struct crypto_blkcipher *tfm_arc4;
656 struct scatterlist sgin, sgout;
657 struct blkcipher_desc desc;
658 unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
659
660 get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
661
662 tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
Shirish Pargaonkar7a8587e2011-01-29 13:54:58 -0600663 if (IS_ERR(tfm_arc4)) {
664 rc = PTR_ERR(tfm_arc4);
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500665 cERROR(1, "could not allocate crypto API arc4\n");
Shirish Pargaonkar7a8587e2011-01-29 13:54:58 -0600666 return rc;
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500667 }
668
669 desc.tfm = tfm_arc4;
670
671 crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
672 CIFS_SESS_KEY_SIZE);
673
674 sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
Shirish Pargaonkard3686d52010-10-28 09:53:07 -0500675 sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500676
677 rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
678 if (rc) {
679 cERROR(1, "could not encrypt session key rc: %d\n", rc);
680 crypto_free_blkcipher(tfm_arc4);
681 return rc;
682 }
683
684 /* make secondary_key/nonce as session key */
685 memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
686 /* and make len as that of session key only */
687 ses->auth_key.len = CIFS_SESS_KEY_SIZE;
688
689 crypto_free_blkcipher(tfm_arc4);
690
691 return 0;
692}
693
694void
695cifs_crypto_shash_release(struct TCP_Server_Info *server)
696{
697 if (server->secmech.md5)
698 crypto_free_shash(server->secmech.md5);
699
700 if (server->secmech.hmacmd5)
701 crypto_free_shash(server->secmech.hmacmd5);
702
703 kfree(server->secmech.sdeschmacmd5);
704
705 kfree(server->secmech.sdescmd5);
706}
707
708int
709cifs_crypto_shash_allocate(struct TCP_Server_Info *server)
710{
711 int rc;
712 unsigned int size;
713
714 server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600715 if (IS_ERR(server->secmech.hmacmd5)) {
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500716 cERROR(1, "could not allocate crypto hmacmd5\n");
717 return PTR_ERR(server->secmech.hmacmd5);
718 }
719
720 server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
Shirish Pargaonkaree2c9252011-01-27 09:58:04 -0600721 if (IS_ERR(server->secmech.md5)) {
Shirish Pargaonkard2b91522010-10-21 14:25:08 -0500722 cERROR(1, "could not allocate crypto md5\n");
723 rc = PTR_ERR(server->secmech.md5);
724 goto crypto_allocate_md5_fail;
725 }
726
727 size = sizeof(struct shash_desc) +
728 crypto_shash_descsize(server->secmech.hmacmd5);
729 server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
730 if (!server->secmech.sdeschmacmd5) {
731 cERROR(1, "cifs_crypto_shash_allocate: can't alloc hmacmd5\n");
732 rc = -ENOMEM;
733 goto crypto_allocate_hmacmd5_sdesc_fail;
734 }
735 server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
736 server->secmech.sdeschmacmd5->shash.flags = 0x0;
737
738
739 size = sizeof(struct shash_desc) +
740 crypto_shash_descsize(server->secmech.md5);
741 server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
742 if (!server->secmech.sdescmd5) {
743 cERROR(1, "cifs_crypto_shash_allocate: can't alloc md5\n");
744 rc = -ENOMEM;
745 goto crypto_allocate_md5_sdesc_fail;
746 }
747 server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
748 server->secmech.sdescmd5->shash.flags = 0x0;
749
750 return 0;
751
752crypto_allocate_md5_sdesc_fail:
753 kfree(server->secmech.sdeschmacmd5);
754
755crypto_allocate_hmacmd5_sdesc_fail:
756 crypto_free_shash(server->secmech.md5);
757
758crypto_allocate_md5_fail:
759 crypto_free_shash(server->secmech.hmacmd5);
760
761 return rc;
762}