1 /*
2 * fs/cifs/sess.c
3 *
4 * SMB/CIFS session setup handling routines
5 *
6 * Copyright (c) International Business Machines Corp., 2006, 2009
7 * Author(s): Steve French (sfrench@us.ibm.com)
8 *
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24 #include "cifspdu.h"
25 #include "cifsglob.h"
26 #include "cifsproto.h"
27 #include "cifs_unicode.h"
28 #include "cifs_debug.h"
29 #include "ntlmssp.h"
30 #include "nterr.h"
31 #include <linux/utsname.h>
32 #include <linux/slab.h>
33 #include "cifs_spnego.h"
34
35 /*
36 * Checks if this is the first smb session to be reconnected after
37 * the socket has been reestablished (so we know whether to use vc 0).
38 * Called while holding the cifs_tcp_ses_lock, so do not block
39 */
is_first_ses_reconnect(struct cifs_ses * ses)40 static bool is_first_ses_reconnect(struct cifs_ses *ses)
41 {
42 struct list_head *tmp;
43 struct cifs_ses *tmp_ses;
44
45 list_for_each(tmp, &ses->server->smb_ses_list) {
46 tmp_ses = list_entry(tmp, struct cifs_ses,
47 smb_ses_list);
48 if (tmp_ses->need_reconnect == false)
49 return false;
50 }
51 /* could not find a session that was already connected,
52 this must be the first one we are reconnecting */
53 return true;
54 }
55
56 /*
57 * vc number 0 is treated specially by some servers, and should be the
58 * first one we request. After that we can use vcnumbers up to maxvcs,
59 * one for each smb session (some Windows versions set maxvcs incorrectly
60 * so maxvc=1 can be ignored). If we have too many vcs, we can reuse
61 * any vc but zero (some servers reset the connection on vcnum zero)
62 *
63 */
get_next_vcnum(struct cifs_ses * ses)64 static __le16 get_next_vcnum(struct cifs_ses *ses)
65 {
66 __u16 vcnum = 0;
67 struct list_head *tmp;
68 struct cifs_ses *tmp_ses;
69 __u16 max_vcs = ses->server->max_vcs;
70 __u16 i;
71 int free_vc_found = 0;
72
73 /* Quoting the MS-SMB specification: "Windows-based SMB servers set this
74 field to one but do not enforce this limit, which allows an SMB client
75 to establish more virtual circuits than allowed by this value ... but
76 other server implementations can enforce this limit." */
77 if (max_vcs < 2)
78 max_vcs = 0xFFFF;
79
80 spin_lock(&cifs_tcp_ses_lock);
81 if ((ses->need_reconnect) && is_first_ses_reconnect(ses))
82 goto get_vc_num_exit; /* vcnum will be zero */
83 for (i = ses->server->srv_count - 1; i < max_vcs; i++) {
84 if (i == 0) /* this is the only connection, use vc 0 */
85 break;
86
87 free_vc_found = 1;
88
89 list_for_each(tmp, &ses->server->smb_ses_list) {
90 tmp_ses = list_entry(tmp, struct cifs_ses,
91 smb_ses_list);
92 if (tmp_ses->vcnum == i) {
93 free_vc_found = 0;
94 break; /* found duplicate, try next vcnum */
95 }
96 }
97 if (free_vc_found)
98 break; /* we found a vcnumber that will work - use it */
99 }
100
101 if (i == 0)
102 vcnum = 0; /* for most common case, ie if one smb session, use
103 vc zero. Also for case when no free vcnum, zero
104 is safest to send (some clients only send zero) */
105 else if (free_vc_found == 0)
106 vcnum = 1; /* we can not reuse vc=0 safely, since some servers
107 reset all uids on that, but 1 is ok. */
108 else
109 vcnum = i;
110 ses->vcnum = vcnum;
111 get_vc_num_exit:
112 spin_unlock(&cifs_tcp_ses_lock);
113
114 return cpu_to_le16(vcnum);
115 }
116
cifs_ssetup_hdr(struct cifs_ses * ses,SESSION_SETUP_ANDX * pSMB)117 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
118 {
119 __u32 capabilities = 0;
120
121 /* init fields common to all four types of SessSetup */
122 /* Note that offsets for first seven fields in req struct are same */
123 /* in CIFS Specs so does not matter which of 3 forms of struct */
124 /* that we use in next few lines */
125 /* Note that header is initialized to zero in header_assemble */
126 pSMB->req.AndXCommand = 0xFF;
127 pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
128 CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
129 USHRT_MAX));
130 pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
131 pSMB->req.VcNumber = get_next_vcnum(ses);
132
133 /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
134
135 /* BB verify whether signing required on neg or just on auth frame
136 (and NTLM case) */
137
138 capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
139 CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
140
141 if (ses->server->sec_mode &
142 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
143 pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
144
145 if (ses->capabilities & CAP_UNICODE) {
146 pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
147 capabilities |= CAP_UNICODE;
148 }
149 if (ses->capabilities & CAP_STATUS32) {
150 pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
151 capabilities |= CAP_STATUS32;
152 }
153 if (ses->capabilities & CAP_DFS) {
154 pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
155 capabilities |= CAP_DFS;
156 }
157 if (ses->capabilities & CAP_UNIX)
158 capabilities |= CAP_UNIX;
159
160 return capabilities;
161 }
162
163 static void
unicode_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)164 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
165 {
166 char *bcc_ptr = *pbcc_area;
167 int bytes_ret = 0;
168
169 /* Copy OS version */
170 bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
171 nls_cp);
172 bcc_ptr += 2 * bytes_ret;
173 bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
174 32, nls_cp);
175 bcc_ptr += 2 * bytes_ret;
176 bcc_ptr += 2; /* trailing null */
177
178 bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
179 32, nls_cp);
180 bcc_ptr += 2 * bytes_ret;
181 bcc_ptr += 2; /* trailing null */
182
183 *pbcc_area = bcc_ptr;
184 }
185
unicode_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)186 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
187 const struct nls_table *nls_cp)
188 {
189 char *bcc_ptr = *pbcc_area;
190 int bytes_ret = 0;
191
192 /* copy domain */
193 if (ses->domainName == NULL) {
194 /* Sending null domain better than using a bogus domain name (as
195 we did briefly in 2.6.18) since server will use its default */
196 *bcc_ptr = 0;
197 *(bcc_ptr+1) = 0;
198 bytes_ret = 0;
199 } else
200 bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
201 CIFS_MAX_DOMAINNAME_LEN, nls_cp);
202 bcc_ptr += 2 * bytes_ret;
203 bcc_ptr += 2; /* account for null terminator */
204
205 *pbcc_area = bcc_ptr;
206 }
207
208
unicode_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)209 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
210 const struct nls_table *nls_cp)
211 {
212 char *bcc_ptr = *pbcc_area;
213 int bytes_ret = 0;
214
215 /* BB FIXME add check that strings total less
216 than 335 or will need to send them as arrays */
217
218 /* unicode strings, must be word aligned before the call */
219 /* if ((long) bcc_ptr % 2) {
220 *bcc_ptr = 0;
221 bcc_ptr++;
222 } */
223 /* copy user */
224 if (ses->user_name == NULL) {
225 /* null user mount */
226 *bcc_ptr = 0;
227 *(bcc_ptr+1) = 0;
228 } else {
229 bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
230 MAX_USERNAME_SIZE, nls_cp);
231 }
232 bcc_ptr += 2 * bytes_ret;
233 bcc_ptr += 2; /* account for null termination */
234
235 unicode_domain_string(&bcc_ptr, ses, nls_cp);
236 unicode_oslm_strings(&bcc_ptr, nls_cp);
237
238 *pbcc_area = bcc_ptr;
239 }
240
ascii_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)241 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
242 const struct nls_table *nls_cp)
243 {
244 char *bcc_ptr = *pbcc_area;
245
246 /* copy user */
247 /* BB what about null user mounts - check that we do this BB */
248 /* copy user */
249 if (ses->user_name != NULL) {
250 strncpy(bcc_ptr, ses->user_name, MAX_USERNAME_SIZE);
251 bcc_ptr += strnlen(ses->user_name, MAX_USERNAME_SIZE);
252 }
253 /* else null user mount */
254 *bcc_ptr = 0;
255 bcc_ptr++; /* account for null termination */
256
257 /* copy domain */
258 if (ses->domainName != NULL) {
259 strncpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
260 bcc_ptr += strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
261 } /* else we will send a null domain name
262 so the server will default to its own domain */
263 *bcc_ptr = 0;
264 bcc_ptr++;
265
266 /* BB check for overflow here */
267
268 strcpy(bcc_ptr, "Linux version ");
269 bcc_ptr += strlen("Linux version ");
270 strcpy(bcc_ptr, init_utsname()->release);
271 bcc_ptr += strlen(init_utsname()->release) + 1;
272
273 strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
274 bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
275
276 *pbcc_area = bcc_ptr;
277 }
278
279 static void
decode_unicode_ssetup(char ** pbcc_area,int bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)280 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
281 const struct nls_table *nls_cp)
282 {
283 int len;
284 char *data = *pbcc_area;
285
286 cFYI(1, "bleft %d", bleft);
287
288 kfree(ses->serverOS);
289 ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
290 cFYI(1, "serverOS=%s", ses->serverOS);
291 len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
292 data += len;
293 bleft -= len;
294 if (bleft <= 0)
295 return;
296
297 kfree(ses->serverNOS);
298 ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
299 cFYI(1, "serverNOS=%s", ses->serverNOS);
300 len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
301 data += len;
302 bleft -= len;
303 if (bleft <= 0)
304 return;
305
306 kfree(ses->serverDomain);
307 ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
308 cFYI(1, "serverDomain=%s", ses->serverDomain);
309
310 return;
311 }
312
decode_ascii_ssetup(char ** pbcc_area,__u16 bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)313 static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
314 struct cifs_ses *ses,
315 const struct nls_table *nls_cp)
316 {
317 int rc = 0;
318 int len;
319 char *bcc_ptr = *pbcc_area;
320
321 cFYI(1, "decode sessetup ascii. bleft %d", bleft);
322
323 len = strnlen(bcc_ptr, bleft);
324 if (len >= bleft)
325 return rc;
326
327 kfree(ses->serverOS);
328
329 ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
330 if (ses->serverOS)
331 strncpy(ses->serverOS, bcc_ptr, len);
332 if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
333 cFYI(1, "OS/2 server");
334 ses->flags |= CIFS_SES_OS2;
335 }
336
337 bcc_ptr += len + 1;
338 bleft -= len + 1;
339
340 len = strnlen(bcc_ptr, bleft);
341 if (len >= bleft)
342 return rc;
343
344 kfree(ses->serverNOS);
345
346 ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
347 if (ses->serverNOS)
348 strncpy(ses->serverNOS, bcc_ptr, len);
349
350 bcc_ptr += len + 1;
351 bleft -= len + 1;
352
353 len = strnlen(bcc_ptr, bleft);
354 if (len > bleft)
355 return rc;
356
357 /* No domain field in LANMAN case. Domain is
358 returned by old servers in the SMB negprot response */
359 /* BB For newer servers which do not support Unicode,
360 but thus do return domain here we could add parsing
361 for it later, but it is not very important */
362 cFYI(1, "ascii: bytes left %d", bleft);
363
364 return rc;
365 }
366
decode_ntlmssp_challenge(char * bcc_ptr,int blob_len,struct cifs_ses * ses)367 static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
368 struct cifs_ses *ses)
369 {
370 unsigned int tioffset; /* challenge message target info area */
371 unsigned int tilen; /* challenge message target info area length */
372
373 CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
374
375 if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
376 cERROR(1, "challenge blob len %d too small", blob_len);
377 return -EINVAL;
378 }
379
380 if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
381 cERROR(1, "blob signature incorrect %s", pblob->Signature);
382 return -EINVAL;
383 }
384 if (pblob->MessageType != NtLmChallenge) {
385 cERROR(1, "Incorrect message type %d", pblob->MessageType);
386 return -EINVAL;
387 }
388
389 memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
390 /* BB we could decode pblob->NegotiateFlags; some may be useful */
391 /* In particular we can examine sign flags */
392 /* BB spec says that if AvId field of MsvAvTimestamp is populated then
393 we must set the MIC field of the AUTHENTICATE_MESSAGE */
394 ses->ntlmssp->server_flags = le32_to_cpu(pblob->NegotiateFlags);
395 tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
396 tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
397 if (tioffset > blob_len || tioffset + tilen > blob_len) {
398 cERROR(1, "tioffset + tilen too high %u + %u", tioffset, tilen);
399 return -EINVAL;
400 }
401 if (tilen) {
402 ses->auth_key.response = kmalloc(tilen, GFP_KERNEL);
403 if (!ses->auth_key.response) {
404 cERROR(1, "Challenge target info allocation failure");
405 return -ENOMEM;
406 }
407 memcpy(ses->auth_key.response, bcc_ptr + tioffset, tilen);
408 ses->auth_key.len = tilen;
409 }
410
411 return 0;
412 }
413
414 /* BB Move to ntlmssp.c eventually */
415
416 /* We do not malloc the blob, it is passed in pbuffer, because
417 it is fixed size, and small, making this approach cleaner */
build_ntlmssp_negotiate_blob(unsigned char * pbuffer,struct cifs_ses * ses)418 static void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
419 struct cifs_ses *ses)
420 {
421 NEGOTIATE_MESSAGE *sec_blob = (NEGOTIATE_MESSAGE *)pbuffer;
422 __u32 flags;
423
424 memset(pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
425 memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
426 sec_blob->MessageType = NtLmNegotiate;
427
428 /* BB is NTLMV2 session security format easier to use here? */
429 flags = NTLMSSP_NEGOTIATE_56 | NTLMSSP_REQUEST_TARGET |
430 NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
431 NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
432 if (ses->server->sec_mode &
433 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
434 flags |= NTLMSSP_NEGOTIATE_SIGN;
435 if (!ses->server->session_estab)
436 flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
437 }
438
439 sec_blob->NegotiateFlags = cpu_to_le32(flags);
440
441 sec_blob->WorkstationName.BufferOffset = 0;
442 sec_blob->WorkstationName.Length = 0;
443 sec_blob->WorkstationName.MaximumLength = 0;
444
445 /* Domain name is sent on the Challenge not Negotiate NTLMSSP request */
446 sec_blob->DomainName.BufferOffset = 0;
447 sec_blob->DomainName.Length = 0;
448 sec_blob->DomainName.MaximumLength = 0;
449 }
450
451 /* We do not malloc the blob, it is passed in pbuffer, because its
452 maximum possible size is fixed and small, making this approach cleaner.
453 This function returns the length of the data in the blob */
build_ntlmssp_auth_blob(unsigned char * pbuffer,u16 * buflen,struct cifs_ses * ses,const struct nls_table * nls_cp)454 static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
455 u16 *buflen,
456 struct cifs_ses *ses,
457 const struct nls_table *nls_cp)
458 {
459 int rc;
460 AUTHENTICATE_MESSAGE *sec_blob = (AUTHENTICATE_MESSAGE *)pbuffer;
461 __u32 flags;
462 unsigned char *tmp;
463
464 memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
465 sec_blob->MessageType = NtLmAuthenticate;
466
467 flags = NTLMSSP_NEGOTIATE_56 |
468 NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
469 NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
470 NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
471 if (ses->server->sec_mode &
472 (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
473 flags |= NTLMSSP_NEGOTIATE_SIGN;
474 if (!ses->server->session_estab)
475 flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
476 }
477
478 tmp = pbuffer + sizeof(AUTHENTICATE_MESSAGE);
479 sec_blob->NegotiateFlags = cpu_to_le32(flags);
480
481 sec_blob->LmChallengeResponse.BufferOffset =
482 cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
483 sec_blob->LmChallengeResponse.Length = 0;
484 sec_blob->LmChallengeResponse.MaximumLength = 0;
485
486 sec_blob->NtChallengeResponse.BufferOffset = cpu_to_le32(tmp - pbuffer);
487 rc = setup_ntlmv2_rsp(ses, nls_cp);
488 if (rc) {
489 cERROR(1, "Error %d during NTLMSSP authentication", rc);
490 goto setup_ntlmv2_ret;
491 }
492 memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
493 ses->auth_key.len - CIFS_SESS_KEY_SIZE);
494 tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
495
496 sec_blob->NtChallengeResponse.Length =
497 cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
498 sec_blob->NtChallengeResponse.MaximumLength =
499 cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
500
501 if (ses->domainName == NULL) {
502 sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
503 sec_blob->DomainName.Length = 0;
504 sec_blob->DomainName.MaximumLength = 0;
505 tmp += 2;
506 } else {
507 int len;
508 len = cifs_strtoUTF16((__le16 *)tmp, ses->domainName,
509 MAX_USERNAME_SIZE, nls_cp);
510 len *= 2; /* unicode is 2 bytes each */
511 sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
512 sec_blob->DomainName.Length = cpu_to_le16(len);
513 sec_blob->DomainName.MaximumLength = cpu_to_le16(len);
514 tmp += len;
515 }
516
517 if (ses->user_name == NULL) {
518 sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
519 sec_blob->UserName.Length = 0;
520 sec_blob->UserName.MaximumLength = 0;
521 tmp += 2;
522 } else {
523 int len;
524 len = cifs_strtoUTF16((__le16 *)tmp, ses->user_name,
525 MAX_USERNAME_SIZE, nls_cp);
526 len *= 2; /* unicode is 2 bytes each */
527 sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
528 sec_blob->UserName.Length = cpu_to_le16(len);
529 sec_blob->UserName.MaximumLength = cpu_to_le16(len);
530 tmp += len;
531 }
532
533 sec_blob->WorkstationName.BufferOffset = cpu_to_le32(tmp - pbuffer);
534 sec_blob->WorkstationName.Length = 0;
535 sec_blob->WorkstationName.MaximumLength = 0;
536 tmp += 2;
537
538 if (((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) ||
539 (ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
540 && !calc_seckey(ses)) {
541 memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
542 sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
543 sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
544 sec_blob->SessionKey.MaximumLength =
545 cpu_to_le16(CIFS_CPHTXT_SIZE);
546 tmp += CIFS_CPHTXT_SIZE;
547 } else {
548 sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
549 sec_blob->SessionKey.Length = 0;
550 sec_blob->SessionKey.MaximumLength = 0;
551 }
552
553 setup_ntlmv2_ret:
554 *buflen = tmp - pbuffer;
555 return rc;
556 }
557
558 int
CIFS_SessSetup(unsigned int xid,struct cifs_ses * ses,const struct nls_table * nls_cp)559 CIFS_SessSetup(unsigned int xid, struct cifs_ses *ses,
560 const struct nls_table *nls_cp)
561 {
562 int rc = 0;
563 int wct;
564 struct smb_hdr *smb_buf;
565 char *bcc_ptr;
566 char *str_area;
567 SESSION_SETUP_ANDX *pSMB;
568 __u32 capabilities;
569 __u16 count;
570 int resp_buf_type;
571 struct kvec iov[3];
572 enum securityEnum type;
573 __u16 action, bytes_remaining;
574 struct key *spnego_key = NULL;
575 __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
576 u16 blob_len;
577 char *ntlmsspblob = NULL;
578
579 if (ses == NULL)
580 return -EINVAL;
581
582 type = ses->server->secType;
583 cFYI(1, "sess setup type %d", type);
584 if (type == RawNTLMSSP) {
585 /* if memory allocation is successful, caller of this function
586 * frees it.
587 */
588 ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
589 if (!ses->ntlmssp)
590 return -ENOMEM;
591 }
592
593 ssetup_ntlmssp_authenticate:
594 if (phase == NtLmChallenge)
595 phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
596
597 if (type == LANMAN) {
598 #ifndef CONFIG_CIFS_WEAK_PW_HASH
599 /* LANMAN and plaintext are less secure and off by default.
600 So we make this explicitly be turned on in kconfig (in the
601 build) and turned on at runtime (changed from the default)
602 in proc/fs/cifs or via mount parm. Unfortunately this is
603 needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
604 return -EOPNOTSUPP;
605 #endif
606 wct = 10; /* lanman 2 style sessionsetup */
607 } else if ((type == NTLM) || (type == NTLMv2)) {
608 /* For NTLMv2 failures eventually may need to retry NTLM */
609 wct = 13; /* old style NTLM sessionsetup */
610 } else /* same size: negotiate or auth, NTLMSSP or extended security */
611 wct = 12;
612
613 rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
614 (void **)&smb_buf);
615 if (rc)
616 return rc;
617
618 pSMB = (SESSION_SETUP_ANDX *)smb_buf;
619
620 capabilities = cifs_ssetup_hdr(ses, pSMB);
621
622 /* we will send the SMB in three pieces:
623 a fixed length beginning part, an optional
624 SPNEGO blob (which can be zero length), and a
625 last part which will include the strings
626 and rest of bcc area. This allows us to avoid
627 a large buffer 17K allocation */
628 iov[0].iov_base = (char *)pSMB;
629 iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
630
631 /* setting this here allows the code at the end of the function
632 to free the request buffer if there's an error */
633 resp_buf_type = CIFS_SMALL_BUFFER;
634
635 /* 2000 big enough to fit max user, domain, NOS name etc. */
636 str_area = kmalloc(2000, GFP_KERNEL);
637 if (str_area == NULL) {
638 rc = -ENOMEM;
639 goto ssetup_exit;
640 }
641 bcc_ptr = str_area;
642
643 ses->flags &= ~CIFS_SES_LANMAN;
644
645 iov[1].iov_base = NULL;
646 iov[1].iov_len = 0;
647
648 if (type == LANMAN) {
649 #ifdef CONFIG_CIFS_WEAK_PW_HASH
650 char lnm_session_key[CIFS_AUTH_RESP_SIZE];
651
652 pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
653
654 /* no capabilities flags in old lanman negotiation */
655
656 pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
657
658 /* Calculate hash with password and copy into bcc_ptr.
659 * Encryption Key (stored as in cryptkey) gets used if the
660 * security mode bit in Negottiate Protocol response states
661 * to use challenge/response method (i.e. Password bit is 1).
662 */
663
664 rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
665 ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
666 true : false, lnm_session_key);
667
668 ses->flags |= CIFS_SES_LANMAN;
669 memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
670 bcc_ptr += CIFS_AUTH_RESP_SIZE;
671
672 /* can not sign if LANMAN negotiated so no need
673 to calculate signing key? but what if server
674 changed to do higher than lanman dialect and
675 we reconnected would we ever calc signing_key? */
676
677 cFYI(1, "Negotiating LANMAN setting up strings");
678 /* Unicode not allowed for LANMAN dialects */
679 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
680 #endif
681 } else if (type == NTLM) {
682 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
683 pSMB->req_no_secext.CaseInsensitivePasswordLength =
684 cpu_to_le16(CIFS_AUTH_RESP_SIZE);
685 pSMB->req_no_secext.CaseSensitivePasswordLength =
686 cpu_to_le16(CIFS_AUTH_RESP_SIZE);
687
688 /* calculate ntlm response and session key */
689 rc = setup_ntlm_response(ses, nls_cp);
690 if (rc) {
691 cERROR(1, "Error %d during NTLM authentication", rc);
692 goto ssetup_exit;
693 }
694
695 /* copy ntlm response */
696 memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
697 CIFS_AUTH_RESP_SIZE);
698 bcc_ptr += CIFS_AUTH_RESP_SIZE;
699 memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
700 CIFS_AUTH_RESP_SIZE);
701 bcc_ptr += CIFS_AUTH_RESP_SIZE;
702
703 if (ses->capabilities & CAP_UNICODE) {
704 /* unicode strings must be word aligned */
705 if (iov[0].iov_len % 2) {
706 *bcc_ptr = 0;
707 bcc_ptr++;
708 }
709 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
710 } else
711 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
712 } else if (type == NTLMv2) {
713 pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
714
715 /* LM2 password would be here if we supported it */
716 pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
717
718 /* calculate nlmv2 response and session key */
719 rc = setup_ntlmv2_rsp(ses, nls_cp);
720 if (rc) {
721 cERROR(1, "Error %d during NTLMv2 authentication", rc);
722 goto ssetup_exit;
723 }
724 memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
725 ses->auth_key.len - CIFS_SESS_KEY_SIZE);
726 bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
727
728 /* set case sensitive password length after tilen may get
729 * assigned, tilen is 0 otherwise.
730 */
731 pSMB->req_no_secext.CaseSensitivePasswordLength =
732 cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
733
734 if (ses->capabilities & CAP_UNICODE) {
735 if (iov[0].iov_len % 2) {
736 *bcc_ptr = 0;
737 bcc_ptr++;
738 }
739 unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
740 } else
741 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
742 } else if (type == Kerberos) {
743 #ifdef CONFIG_CIFS_UPCALL
744 struct cifs_spnego_msg *msg;
745
746 spnego_key = cifs_get_spnego_key(ses);
747 if (IS_ERR(spnego_key)) {
748 rc = PTR_ERR(spnego_key);
749 spnego_key = NULL;
750 goto ssetup_exit;
751 }
752
753 msg = spnego_key->payload.data;
754 /* check version field to make sure that cifs.upcall is
755 sending us a response in an expected form */
756 if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
757 cERROR(1, "incorrect version of cifs.upcall (expected"
758 " %d but got %d)",
759 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
760 rc = -EKEYREJECTED;
761 goto ssetup_exit;
762 }
763
764 ses->auth_key.response = kmalloc(msg->sesskey_len, GFP_KERNEL);
765 if (!ses->auth_key.response) {
766 cERROR(1, "Kerberos can't allocate (%u bytes) memory",
767 msg->sesskey_len);
768 rc = -ENOMEM;
769 goto ssetup_exit;
770 }
771 memcpy(ses->auth_key.response, msg->data, msg->sesskey_len);
772 ses->auth_key.len = msg->sesskey_len;
773
774 pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
775 capabilities |= CAP_EXTENDED_SECURITY;
776 pSMB->req.Capabilities = cpu_to_le32(capabilities);
777 iov[1].iov_base = msg->data + msg->sesskey_len;
778 iov[1].iov_len = msg->secblob_len;
779 pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
780
781 if (ses->capabilities & CAP_UNICODE) {
782 /* unicode strings must be word aligned */
783 if ((iov[0].iov_len + iov[1].iov_len) % 2) {
784 *bcc_ptr = 0;
785 bcc_ptr++;
786 }
787 unicode_oslm_strings(&bcc_ptr, nls_cp);
788 unicode_domain_string(&bcc_ptr, ses, nls_cp);
789 } else
790 /* BB: is this right? */
791 ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
792 #else /* ! CONFIG_CIFS_UPCALL */
793 cERROR(1, "Kerberos negotiated but upcall support disabled!");
794 rc = -ENOSYS;
795 goto ssetup_exit;
796 #endif /* CONFIG_CIFS_UPCALL */
797 } else if (type == RawNTLMSSP) {
798 if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
799 cERROR(1, "NTLMSSP requires Unicode support");
800 rc = -ENOSYS;
801 goto ssetup_exit;
802 }
803
804 cFYI(1, "ntlmssp session setup phase %d", phase);
805 pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
806 capabilities |= CAP_EXTENDED_SECURITY;
807 pSMB->req.Capabilities |= cpu_to_le32(capabilities);
808 switch(phase) {
809 case NtLmNegotiate:
810 build_ntlmssp_negotiate_blob(
811 pSMB->req.SecurityBlob, ses);
812 iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
813 iov[1].iov_base = pSMB->req.SecurityBlob;
814 pSMB->req.SecurityBlobLength =
815 cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
816 break;
817 case NtLmAuthenticate:
818 /*
819 * 5 is an empirical value, large enough to hold
820 * authenticate message plus max 10 of av paris,
821 * domain, user, workstation names, flags, etc.
822 */
823 ntlmsspblob = kzalloc(
824 5*sizeof(struct _AUTHENTICATE_MESSAGE),
825 GFP_KERNEL);
826 if (!ntlmsspblob) {
827 cERROR(1, "Can't allocate NTLMSSP blob");
828 rc = -ENOMEM;
829 goto ssetup_exit;
830 }
831
832 rc = build_ntlmssp_auth_blob(ntlmsspblob,
833 &blob_len, ses, nls_cp);
834 if (rc)
835 goto ssetup_exit;
836 iov[1].iov_len = blob_len;
837 iov[1].iov_base = ntlmsspblob;
838 pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
839 /*
840 * Make sure that we tell the server that we are using
841 * the uid that it just gave us back on the response
842 * (challenge)
843 */
844 smb_buf->Uid = ses->Suid;
845 break;
846 default:
847 cERROR(1, "invalid phase %d", phase);
848 rc = -ENOSYS;
849 goto ssetup_exit;
850 }
851 /* unicode strings must be word aligned */
852 if ((iov[0].iov_len + iov[1].iov_len) % 2) {
853 *bcc_ptr = 0;
854 bcc_ptr++;
855 }
856 unicode_oslm_strings(&bcc_ptr, nls_cp);
857 } else {
858 cERROR(1, "secType %d not supported!", type);
859 rc = -ENOSYS;
860 goto ssetup_exit;
861 }
862
863 iov[2].iov_base = str_area;
864 iov[2].iov_len = (long) bcc_ptr - (long) str_area;
865
866 count = iov[1].iov_len + iov[2].iov_len;
867 smb_buf->smb_buf_length =
868 cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
869
870 put_bcc(count, smb_buf);
871
872 rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
873 CIFS_LOG_ERROR);
874 /* SMB request buf freed in SendReceive2 */
875
876 pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
877 smb_buf = (struct smb_hdr *)iov[0].iov_base;
878
879 if ((type == RawNTLMSSP) && (smb_buf->Status.CifsError ==
880 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
881 if (phase != NtLmNegotiate) {
882 cERROR(1, "Unexpected more processing error");
883 goto ssetup_exit;
884 }
885 /* NTLMSSP Negotiate sent now processing challenge (response) */
886 phase = NtLmChallenge; /* process ntlmssp challenge */
887 rc = 0; /* MORE_PROC rc is not an error here, but expected */
888 }
889 if (rc)
890 goto ssetup_exit;
891
892 if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
893 rc = -EIO;
894 cERROR(1, "bad word count %d", smb_buf->WordCount);
895 goto ssetup_exit;
896 }
897 action = le16_to_cpu(pSMB->resp.Action);
898 if (action & GUEST_LOGIN)
899 cFYI(1, "Guest login"); /* BB mark SesInfo struct? */
900 ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
901 cFYI(1, "UID = %d ", ses->Suid);
902 /* response can have either 3 or 4 word count - Samba sends 3 */
903 /* and lanman response is 3 */
904 bytes_remaining = get_bcc(smb_buf);
905 bcc_ptr = pByteArea(smb_buf);
906
907 if (smb_buf->WordCount == 4) {
908 blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
909 if (blob_len > bytes_remaining) {
910 cERROR(1, "bad security blob length %d", blob_len);
911 rc = -EINVAL;
912 goto ssetup_exit;
913 }
914 if (phase == NtLmChallenge) {
915 rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
916 /* now goto beginning for ntlmssp authenticate phase */
917 if (rc)
918 goto ssetup_exit;
919 }
920 bcc_ptr += blob_len;
921 bytes_remaining -= blob_len;
922 }
923
924 /* BB check if Unicode and decode strings */
925 if (bytes_remaining == 0) {
926 /* no string area to decode, do nothing */
927 } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
928 /* unicode string area must be word-aligned */
929 if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
930 ++bcc_ptr;
931 --bytes_remaining;
932 }
933 decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
934 } else {
935 rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
936 ses, nls_cp);
937 }
938
939 ssetup_exit:
940 if (spnego_key) {
941 key_revoke(spnego_key);
942 key_put(spnego_key);
943 }
944 kfree(str_area);
945 kfree(ntlmsspblob);
946 ntlmsspblob = NULL;
947 if (resp_buf_type == CIFS_SMALL_BUFFER) {
948 cFYI(1, "ssetup freeing small buf %p", iov[0].iov_base);
949 cifs_small_buf_release(iov[0].iov_base);
950 } else if (resp_buf_type == CIFS_LARGE_BUFFER)
951 cifs_buf_release(iov[0].iov_base);
952
953 /* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
954 if ((phase == NtLmChallenge) && (rc == 0))
955 goto ssetup_ntlmssp_authenticate;
956
957 return rc;
958 }
959