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1 // SPDX-License-Identifier: LGPL-2.1
2 /*
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  */
10 
11 #include "cifspdu.h"
12 #include "cifsglob.h"
13 #include "cifsproto.h"
14 #include "cifs_unicode.h"
15 #include "cifs_debug.h"
16 #include "ntlmssp.h"
17 #include "nterr.h"
18 #include <linux/utsname.h>
19 #include <linux/slab.h>
20 #include <linux/version.h>
21 #include "cifsfs.h"
22 #include "cifs_spnego.h"
23 #include "smb2proto.h"
24 #include "fs_context.h"
25 
26 static int
27 cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
28 		     struct cifs_server_iface *iface);
29 
30 bool
is_server_using_iface(struct TCP_Server_Info * server,struct cifs_server_iface * iface)31 is_server_using_iface(struct TCP_Server_Info *server,
32 		      struct cifs_server_iface *iface)
33 {
34 	struct sockaddr_in *i4 = (struct sockaddr_in *)&iface->sockaddr;
35 	struct sockaddr_in6 *i6 = (struct sockaddr_in6 *)&iface->sockaddr;
36 	struct sockaddr_in *s4 = (struct sockaddr_in *)&server->dstaddr;
37 	struct sockaddr_in6 *s6 = (struct sockaddr_in6 *)&server->dstaddr;
38 
39 	if (server->dstaddr.ss_family != iface->sockaddr.ss_family)
40 		return false;
41 	if (server->dstaddr.ss_family == AF_INET) {
42 		if (s4->sin_addr.s_addr != i4->sin_addr.s_addr)
43 			return false;
44 	} else if (server->dstaddr.ss_family == AF_INET6) {
45 		if (memcmp(&s6->sin6_addr, &i6->sin6_addr,
46 			   sizeof(i6->sin6_addr)) != 0)
47 			return false;
48 	} else {
49 		/* unknown family.. */
50 		return false;
51 	}
52 	return true;
53 }
54 
is_ses_using_iface(struct cifs_ses * ses,struct cifs_server_iface * iface)55 bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
56 {
57 	int i;
58 
59 	spin_lock(&ses->chan_lock);
60 	for (i = 0; i < ses->chan_count; i++) {
61 		if (ses->chans[i].iface == iface) {
62 			spin_unlock(&ses->chan_lock);
63 			return true;
64 		}
65 	}
66 	spin_unlock(&ses->chan_lock);
67 	return false;
68 }
69 
70 /* channel helper functions. assumed that chan_lock is held by caller. */
71 
72 unsigned int
cifs_ses_get_chan_index(struct cifs_ses * ses,struct TCP_Server_Info * server)73 cifs_ses_get_chan_index(struct cifs_ses *ses,
74 			struct TCP_Server_Info *server)
75 {
76 	unsigned int i;
77 
78 	for (i = 0; i < ses->chan_count; i++) {
79 		if (ses->chans[i].server == server)
80 			return i;
81 	}
82 
83 	/* If we didn't find the channel, it is likely a bug */
84 	if (server)
85 		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
86 			 server->conn_id);
87 	WARN_ON(1);
88 	return 0;
89 }
90 
91 void
cifs_chan_set_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)92 cifs_chan_set_in_reconnect(struct cifs_ses *ses,
93 			     struct TCP_Server_Info *server)
94 {
95 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
96 
97 	ses->chans[chan_index].in_reconnect = true;
98 }
99 
100 void
cifs_chan_clear_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)101 cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
102 			     struct TCP_Server_Info *server)
103 {
104 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
105 
106 	ses->chans[chan_index].in_reconnect = false;
107 }
108 
109 bool
cifs_chan_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)110 cifs_chan_in_reconnect(struct cifs_ses *ses,
111 			  struct TCP_Server_Info *server)
112 {
113 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
114 
115 	return CIFS_CHAN_IN_RECONNECT(ses, chan_index);
116 }
117 
118 void
cifs_chan_set_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)119 cifs_chan_set_need_reconnect(struct cifs_ses *ses,
120 			     struct TCP_Server_Info *server)
121 {
122 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
123 
124 	set_bit(chan_index, &ses->chans_need_reconnect);
125 	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
126 		 chan_index, ses->chans_need_reconnect);
127 }
128 
129 void
cifs_chan_clear_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)130 cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
131 			       struct TCP_Server_Info *server)
132 {
133 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
134 
135 	clear_bit(chan_index, &ses->chans_need_reconnect);
136 	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
137 		 chan_index, ses->chans_need_reconnect);
138 }
139 
140 bool
cifs_chan_needs_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)141 cifs_chan_needs_reconnect(struct cifs_ses *ses,
142 			  struct TCP_Server_Info *server)
143 {
144 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
145 
146 	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
147 }
148 
149 bool
cifs_chan_is_iface_active(struct cifs_ses * ses,struct TCP_Server_Info * server)150 cifs_chan_is_iface_active(struct cifs_ses *ses,
151 			  struct TCP_Server_Info *server)
152 {
153 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
154 
155 	return ses->chans[chan_index].iface &&
156 		ses->chans[chan_index].iface->is_active;
157 }
158 
159 /* returns number of channels added */
cifs_try_adding_channels(struct cifs_sb_info * cifs_sb,struct cifs_ses * ses)160 int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
161 {
162 	struct TCP_Server_Info *server = ses->server;
163 	int old_chan_count, new_chan_count;
164 	int left;
165 	int rc = 0;
166 	int tries = 0;
167 	size_t iface_weight = 0, iface_min_speed = 0;
168 	struct cifs_server_iface *iface = NULL, *niface = NULL;
169 	struct cifs_server_iface *last_iface = NULL;
170 
171 	spin_lock(&ses->chan_lock);
172 
173 	new_chan_count = old_chan_count = ses->chan_count;
174 	left = ses->chan_max - ses->chan_count;
175 
176 	if (left <= 0) {
177 		spin_unlock(&ses->chan_lock);
178 		cifs_dbg(FYI,
179 			 "ses already at max_channels (%zu), nothing to open\n",
180 			 ses->chan_max);
181 		return 0;
182 	}
183 
184 	if (server->dialect < SMB30_PROT_ID) {
185 		spin_unlock(&ses->chan_lock);
186 		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
187 		return 0;
188 	}
189 
190 	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
191 		spin_unlock(&ses->chan_lock);
192 		cifs_server_dbg(VFS, "no multichannel support\n");
193 		return 0;
194 	}
195 	spin_unlock(&ses->chan_lock);
196 
197 	while (left > 0) {
198 
199 		tries++;
200 		if (tries > 3*ses->chan_max) {
201 			cifs_dbg(VFS, "too many channel open attempts (%d channels left to open)\n",
202 				 left);
203 			break;
204 		}
205 
206 		spin_lock(&ses->iface_lock);
207 		if (!ses->iface_count) {
208 			spin_unlock(&ses->iface_lock);
209 			cifs_dbg(VFS, "server %s does not advertise interfaces\n",
210 				      ses->server->hostname);
211 			break;
212 		}
213 
214 		if (!iface)
215 			iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
216 						 iface_head);
217 		last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
218 					     iface_head);
219 		iface_min_speed = last_iface->speed;
220 
221 		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
222 				    iface_head) {
223 			/* do not mix rdma and non-rdma interfaces */
224 			if (iface->rdma_capable != ses->server->rdma)
225 				continue;
226 
227 			/* skip ifaces that are unusable */
228 			if (!iface->is_active ||
229 			    (is_ses_using_iface(ses, iface) &&
230 			     !iface->rss_capable))
231 				continue;
232 
233 			/* check if we already allocated enough channels */
234 			iface_weight = iface->speed / iface_min_speed;
235 
236 			if (iface->weight_fulfilled >= iface_weight)
237 				continue;
238 
239 			/* take ref before unlock */
240 			kref_get(&iface->refcount);
241 
242 			spin_unlock(&ses->iface_lock);
243 			rc = cifs_ses_add_channel(cifs_sb, ses, iface);
244 			spin_lock(&ses->iface_lock);
245 
246 			if (rc) {
247 				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
248 					 &iface->sockaddr,
249 					 rc);
250 				kref_put(&iface->refcount, release_iface);
251 				/* failure to add chan should increase weight */
252 				iface->weight_fulfilled++;
253 				continue;
254 			}
255 
256 			iface->num_channels++;
257 			iface->weight_fulfilled++;
258 			cifs_dbg(VFS, "successfully opened new channel on iface:%pIS\n",
259 				 &iface->sockaddr);
260 			break;
261 		}
262 
263 		/* reached end of list. reset weight_fulfilled and start over */
264 		if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
265 			list_for_each_entry(iface, &ses->iface_list, iface_head)
266 				iface->weight_fulfilled = 0;
267 			spin_unlock(&ses->iface_lock);
268 			iface = NULL;
269 			continue;
270 		}
271 		spin_unlock(&ses->iface_lock);
272 
273 		left--;
274 		new_chan_count++;
275 	}
276 
277 	return new_chan_count - old_chan_count;
278 }
279 
280 /*
281  * update the iface for the channel if necessary.
282  * will return 0 when iface is updated, 1 if removed, 2 otherwise
283  * Must be called with chan_lock held.
284  */
285 int
cifs_chan_update_iface(struct cifs_ses * ses,struct TCP_Server_Info * server)286 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
287 {
288 	unsigned int chan_index;
289 	size_t iface_weight = 0, iface_min_speed = 0;
290 	struct cifs_server_iface *iface = NULL;
291 	struct cifs_server_iface *old_iface = NULL;
292 	struct cifs_server_iface *last_iface = NULL;
293 	struct sockaddr_storage ss;
294 	int rc = 0;
295 
296 	spin_lock(&ses->chan_lock);
297 	chan_index = cifs_ses_get_chan_index(ses, server);
298 	if (!chan_index) {
299 		spin_unlock(&ses->chan_lock);
300 		return 0;
301 	}
302 
303 	if (ses->chans[chan_index].iface) {
304 		old_iface = ses->chans[chan_index].iface;
305 		if (old_iface->is_active) {
306 			spin_unlock(&ses->chan_lock);
307 			return 1;
308 		}
309 	}
310 	spin_unlock(&ses->chan_lock);
311 
312 	spin_lock(&server->srv_lock);
313 	ss = server->dstaddr;
314 	spin_unlock(&server->srv_lock);
315 
316 	spin_lock(&ses->iface_lock);
317 	if (!ses->iface_count) {
318 		spin_unlock(&ses->iface_lock);
319 		cifs_dbg(VFS, "server %s does not advertise interfaces\n", ses->server->hostname);
320 		return 0;
321 	}
322 
323 	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
324 				     iface_head);
325 	iface_min_speed = last_iface->speed;
326 
327 	/* then look for a new one */
328 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
329 		if (!chan_index) {
330 			/* if we're trying to get the updated iface for primary channel */
331 			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
332 					       (struct sockaddr *) &iface->sockaddr))
333 				continue;
334 
335 			kref_get(&iface->refcount);
336 			break;
337 		}
338 
339 		/* do not mix rdma and non-rdma interfaces */
340 		if (iface->rdma_capable != server->rdma)
341 			continue;
342 
343 		if (!iface->is_active ||
344 		    (is_ses_using_iface(ses, iface) &&
345 		     !iface->rss_capable)) {
346 			continue;
347 		}
348 
349 		/* check if we already allocated enough channels */
350 		iface_weight = iface->speed / iface_min_speed;
351 
352 		if (iface->weight_fulfilled >= iface_weight)
353 			continue;
354 
355 		kref_get(&iface->refcount);
356 		break;
357 	}
358 
359 	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
360 		rc = 1;
361 		iface = NULL;
362 		cifs_dbg(FYI, "unable to find a suitable iface\n");
363 	}
364 
365 	if (!chan_index && !iface) {
366 		cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
367 			 &ss);
368 		spin_unlock(&ses->iface_lock);
369 		return 0;
370 	}
371 
372 	/* now drop the ref to the current iface */
373 	if (old_iface && iface) {
374 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
375 			 &old_iface->sockaddr,
376 			 &iface->sockaddr);
377 
378 		old_iface->num_channels--;
379 		if (old_iface->weight_fulfilled)
380 			old_iface->weight_fulfilled--;
381 		iface->num_channels++;
382 		iface->weight_fulfilled++;
383 
384 		kref_put(&old_iface->refcount, release_iface);
385 	} else if (old_iface) {
386 		cifs_dbg(FYI, "releasing ref to iface: %pIS\n",
387 			 &old_iface->sockaddr);
388 
389 		old_iface->num_channels--;
390 		if (old_iface->weight_fulfilled)
391 			old_iface->weight_fulfilled--;
392 
393 		kref_put(&old_iface->refcount, release_iface);
394 	} else if (!chan_index) {
395 		/* special case: update interface for primary channel */
396 		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
397 			 &iface->sockaddr);
398 		iface->num_channels++;
399 		iface->weight_fulfilled++;
400 	} else {
401 		WARN_ON(!iface);
402 		cifs_dbg(FYI, "adding new iface: %pIS\n", &iface->sockaddr);
403 	}
404 	spin_unlock(&ses->iface_lock);
405 
406 	spin_lock(&ses->chan_lock);
407 	chan_index = cifs_ses_get_chan_index(ses, server);
408 	ses->chans[chan_index].iface = iface;
409 
410 	/* No iface is found. if secondary chan, drop connection */
411 	if (!iface && CIFS_SERVER_IS_CHAN(server))
412 		ses->chans[chan_index].server = NULL;
413 
414 	spin_unlock(&ses->chan_lock);
415 
416 	if (!iface && CIFS_SERVER_IS_CHAN(server))
417 		cifs_put_tcp_session(server, false);
418 
419 	return rc;
420 }
421 
422 /*
423  * If server is a channel of ses, return the corresponding enclosing
424  * cifs_chan otherwise return NULL.
425  */
426 struct cifs_chan *
cifs_ses_find_chan(struct cifs_ses * ses,struct TCP_Server_Info * server)427 cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server)
428 {
429 	int i;
430 
431 	spin_lock(&ses->chan_lock);
432 	for (i = 0; i < ses->chan_count; i++) {
433 		if (ses->chans[i].server == server) {
434 			spin_unlock(&ses->chan_lock);
435 			return &ses->chans[i];
436 		}
437 	}
438 	spin_unlock(&ses->chan_lock);
439 	return NULL;
440 }
441 
442 static int
cifs_ses_add_channel(struct cifs_sb_info * cifs_sb,struct cifs_ses * ses,struct cifs_server_iface * iface)443 cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
444 		     struct cifs_server_iface *iface)
445 {
446 	struct TCP_Server_Info *chan_server;
447 	struct cifs_chan *chan;
448 	struct smb3_fs_context ctx = {NULL};
449 	static const char unc_fmt[] = "\\%s\\foo";
450 	char unc[sizeof(unc_fmt)+SERVER_NAME_LEN_WITH_NULL] = {0};
451 	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
452 	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
453 	int rc;
454 	unsigned int xid = get_xid();
455 
456 	if (iface->sockaddr.ss_family == AF_INET)
457 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
458 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
459 			 &ipv4->sin_addr);
460 	else
461 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
462 			 ses, iface->speed, iface->rdma_capable ? "yes" : "no",
463 			 &ipv6->sin6_addr);
464 
465 	/*
466 	 * Setup a ctx with mostly the same info as the existing
467 	 * session and overwrite it with the requested iface data.
468 	 *
469 	 * We need to setup at least the fields used for negprot and
470 	 * sesssetup.
471 	 *
472 	 * We only need the ctx here, so we can reuse memory from
473 	 * the session and server without caring about memory
474 	 * management.
475 	 */
476 
477 	/* Always make new connection for now (TODO?) */
478 	ctx.nosharesock = true;
479 
480 	/* Auth */
481 	ctx.domainauto = ses->domainAuto;
482 	ctx.domainname = ses->domainName;
483 
484 	/* no hostname for extra channels */
485 	ctx.server_hostname = "";
486 
487 	ctx.username = ses->user_name;
488 	ctx.password = ses->password;
489 	ctx.sectype = ses->sectype;
490 	ctx.sign = ses->sign;
491 
492 	/* UNC and paths */
493 	/* XXX: Use ses->server->hostname? */
494 	sprintf(unc, unc_fmt, ses->ip_addr);
495 	ctx.UNC = unc;
496 	ctx.prepath = "";
497 
498 	/* Reuse same version as master connection */
499 	ctx.vals = ses->server->vals;
500 	ctx.ops = ses->server->ops;
501 
502 	ctx.noblocksnd = ses->server->noblocksnd;
503 	ctx.noautotune = ses->server->noautotune;
504 	ctx.sockopt_tcp_nodelay = ses->server->tcp_nodelay;
505 	ctx.echo_interval = ses->server->echo_interval / HZ;
506 	ctx.max_credits = ses->server->max_credits;
507 
508 	/*
509 	 * This will be used for encoding/decoding user/domain/pw
510 	 * during sess setup auth.
511 	 */
512 	ctx.local_nls = cifs_sb->local_nls;
513 
514 	/* Use RDMA if possible */
515 	ctx.rdma = iface->rdma_capable;
516 	memcpy(&ctx.dstaddr, &iface->sockaddr, sizeof(struct sockaddr_storage));
517 
518 	/* reuse master con client guid */
519 	memcpy(&ctx.client_guid, ses->server->client_guid,
520 	       SMB2_CLIENT_GUID_SIZE);
521 	ctx.use_client_guid = true;
522 
523 	chan_server = cifs_get_tcp_session(&ctx, ses->server);
524 
525 	spin_lock(&ses->chan_lock);
526 	chan = &ses->chans[ses->chan_count];
527 	chan->server = chan_server;
528 	if (IS_ERR(chan->server)) {
529 		rc = PTR_ERR(chan->server);
530 		chan->server = NULL;
531 		spin_unlock(&ses->chan_lock);
532 		goto out;
533 	}
534 	chan->iface = iface;
535 	ses->chan_count++;
536 	atomic_set(&ses->chan_seq, 0);
537 
538 	/* Mark this channel as needing connect/setup */
539 	cifs_chan_set_need_reconnect(ses, chan->server);
540 
541 	spin_unlock(&ses->chan_lock);
542 
543 	mutex_lock(&ses->session_mutex);
544 	/*
545 	 * We need to allocate the server crypto now as we will need
546 	 * to sign packets before we generate the channel signing key
547 	 * (we sign with the session key)
548 	 */
549 	rc = smb311_crypto_shash_allocate(chan->server);
550 	if (rc) {
551 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
552 		mutex_unlock(&ses->session_mutex);
553 		goto out;
554 	}
555 
556 	rc = cifs_negotiate_protocol(xid, ses, chan->server);
557 	if (!rc)
558 		rc = cifs_setup_session(xid, ses, chan->server, cifs_sb->local_nls);
559 
560 	mutex_unlock(&ses->session_mutex);
561 
562 out:
563 	if (rc && chan->server) {
564 		/*
565 		 * we should avoid race with these delayed works before we
566 		 * remove this channel
567 		 */
568 		cancel_delayed_work_sync(&chan->server->echo);
569 		cancel_delayed_work_sync(&chan->server->resolve);
570 		cancel_delayed_work_sync(&chan->server->reconnect);
571 
572 		spin_lock(&ses->chan_lock);
573 		/* we rely on all bits beyond chan_count to be clear */
574 		cifs_chan_clear_need_reconnect(ses, chan->server);
575 		ses->chan_count--;
576 		/*
577 		 * chan_count should never reach 0 as at least the primary
578 		 * channel is always allocated
579 		 */
580 		WARN_ON(ses->chan_count < 1);
581 		spin_unlock(&ses->chan_lock);
582 
583 		cifs_put_tcp_session(chan->server, 0);
584 	}
585 
586 	free_xid(xid);
587 	return rc;
588 }
589 
590 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
cifs_ssetup_hdr(struct cifs_ses * ses,struct TCP_Server_Info * server,SESSION_SETUP_ANDX * pSMB)591 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
592 			     struct TCP_Server_Info *server,
593 			     SESSION_SETUP_ANDX *pSMB)
594 {
595 	__u32 capabilities = 0;
596 
597 	/* init fields common to all four types of SessSetup */
598 	/* Note that offsets for first seven fields in req struct are same  */
599 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
600 	/*	that we use in next few lines                               */
601 	/* Note that header is initialized to zero in header_assemble */
602 	pSMB->req.AndXCommand = 0xFF;
603 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
604 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
605 					USHRT_MAX));
606 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
607 	pSMB->req.VcNumber = cpu_to_le16(1);
608 
609 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
610 
611 	/* BB verify whether signing required on neg or just on auth frame
612 	   (and NTLM case) */
613 
614 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
615 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
616 
617 	if (server->sign)
618 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
619 
620 	if (ses->capabilities & CAP_UNICODE) {
621 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
622 		capabilities |= CAP_UNICODE;
623 	}
624 	if (ses->capabilities & CAP_STATUS32) {
625 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
626 		capabilities |= CAP_STATUS32;
627 	}
628 	if (ses->capabilities & CAP_DFS) {
629 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
630 		capabilities |= CAP_DFS;
631 	}
632 	if (ses->capabilities & CAP_UNIX)
633 		capabilities |= CAP_UNIX;
634 
635 	return capabilities;
636 }
637 
638 static void
unicode_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)639 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
640 {
641 	char *bcc_ptr = *pbcc_area;
642 	int bytes_ret = 0;
643 
644 	/* Copy OS version */
645 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
646 				    nls_cp);
647 	bcc_ptr += 2 * bytes_ret;
648 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
649 				    32, nls_cp);
650 	bcc_ptr += 2 * bytes_ret;
651 	bcc_ptr += 2; /* trailing null */
652 
653 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
654 				    32, nls_cp);
655 	bcc_ptr += 2 * bytes_ret;
656 	bcc_ptr += 2; /* trailing null */
657 
658 	*pbcc_area = bcc_ptr;
659 }
660 
unicode_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)661 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
662 				   const struct nls_table *nls_cp)
663 {
664 	char *bcc_ptr = *pbcc_area;
665 	int bytes_ret = 0;
666 
667 	/* copy domain */
668 	if (ses->domainName == NULL) {
669 		/* Sending null domain better than using a bogus domain name (as
670 		we did briefly in 2.6.18) since server will use its default */
671 		*bcc_ptr = 0;
672 		*(bcc_ptr+1) = 0;
673 		bytes_ret = 0;
674 	} else
675 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
676 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
677 	bcc_ptr += 2 * bytes_ret;
678 	bcc_ptr += 2;  /* account for null terminator */
679 
680 	*pbcc_area = bcc_ptr;
681 }
682 
unicode_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)683 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
684 				   const struct nls_table *nls_cp)
685 {
686 	char *bcc_ptr = *pbcc_area;
687 	int bytes_ret = 0;
688 
689 	/* BB FIXME add check that strings total less
690 	than 335 or will need to send them as arrays */
691 
692 	/* copy user */
693 	if (ses->user_name == NULL) {
694 		/* null user mount */
695 		*bcc_ptr = 0;
696 		*(bcc_ptr+1) = 0;
697 	} else {
698 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
699 					    CIFS_MAX_USERNAME_LEN, nls_cp);
700 	}
701 	bcc_ptr += 2 * bytes_ret;
702 	bcc_ptr += 2; /* account for null termination */
703 
704 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
705 	unicode_oslm_strings(&bcc_ptr, nls_cp);
706 
707 	*pbcc_area = bcc_ptr;
708 }
709 
ascii_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)710 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
711 				 const struct nls_table *nls_cp)
712 {
713 	char *bcc_ptr = *pbcc_area;
714 	int len;
715 
716 	/* copy user */
717 	/* BB what about null user mounts - check that we do this BB */
718 	/* copy user */
719 	if (ses->user_name != NULL) {
720 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
721 		if (WARN_ON_ONCE(len < 0))
722 			len = CIFS_MAX_USERNAME_LEN - 1;
723 		bcc_ptr += len;
724 	}
725 	/* else null user mount */
726 	*bcc_ptr = 0;
727 	bcc_ptr++; /* account for null termination */
728 
729 	/* copy domain */
730 	if (ses->domainName != NULL) {
731 		len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
732 		if (WARN_ON_ONCE(len < 0))
733 			len = CIFS_MAX_DOMAINNAME_LEN - 1;
734 		bcc_ptr += len;
735 	} /* else we will send a null domain name
736 	     so the server will default to its own domain */
737 	*bcc_ptr = 0;
738 	bcc_ptr++;
739 
740 	/* BB check for overflow here */
741 
742 	strcpy(bcc_ptr, "Linux version ");
743 	bcc_ptr += strlen("Linux version ");
744 	strcpy(bcc_ptr, init_utsname()->release);
745 	bcc_ptr += strlen(init_utsname()->release) + 1;
746 
747 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
748 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
749 
750 	*pbcc_area = bcc_ptr;
751 }
752 
753 static void
decode_unicode_ssetup(char ** pbcc_area,int bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)754 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
755 		      const struct nls_table *nls_cp)
756 {
757 	int len;
758 	char *data = *pbcc_area;
759 
760 	cifs_dbg(FYI, "bleft %d\n", bleft);
761 
762 	kfree(ses->serverOS);
763 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
764 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
765 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
766 	data += len;
767 	bleft -= len;
768 	if (bleft <= 0)
769 		return;
770 
771 	kfree(ses->serverNOS);
772 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
773 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
774 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
775 	data += len;
776 	bleft -= len;
777 	if (bleft <= 0)
778 		return;
779 
780 	kfree(ses->serverDomain);
781 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
782 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
783 
784 	return;
785 }
786 
decode_ascii_ssetup(char ** pbcc_area,__u16 bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)787 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
788 				struct cifs_ses *ses,
789 				const struct nls_table *nls_cp)
790 {
791 	int len;
792 	char *bcc_ptr = *pbcc_area;
793 
794 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
795 
796 	len = strnlen(bcc_ptr, bleft);
797 	if (len >= bleft)
798 		return;
799 
800 	kfree(ses->serverOS);
801 
802 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
803 	if (ses->serverOS) {
804 		memcpy(ses->serverOS, bcc_ptr, len);
805 		ses->serverOS[len] = 0;
806 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
807 			cifs_dbg(FYI, "OS/2 server\n");
808 	}
809 
810 	bcc_ptr += len + 1;
811 	bleft -= len + 1;
812 
813 	len = strnlen(bcc_ptr, bleft);
814 	if (len >= bleft)
815 		return;
816 
817 	kfree(ses->serverNOS);
818 
819 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
820 	if (ses->serverNOS) {
821 		memcpy(ses->serverNOS, bcc_ptr, len);
822 		ses->serverNOS[len] = 0;
823 	}
824 
825 	bcc_ptr += len + 1;
826 	bleft -= len + 1;
827 
828 	len = strnlen(bcc_ptr, bleft);
829 	if (len > bleft)
830 		return;
831 
832 	/* No domain field in LANMAN case. Domain is
833 	   returned by old servers in the SMB negprot response */
834 	/* BB For newer servers which do not support Unicode,
835 	   but thus do return domain here we could add parsing
836 	   for it later, but it is not very important */
837 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
838 }
839 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
840 
decode_ntlmssp_challenge(char * bcc_ptr,int blob_len,struct cifs_ses * ses)841 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
842 				    struct cifs_ses *ses)
843 {
844 	unsigned int tioffset; /* challenge message target info area */
845 	unsigned int tilen; /* challenge message target info area length  */
846 	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
847 	__u32 server_flags;
848 
849 	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
850 		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
851 		return -EINVAL;
852 	}
853 
854 	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
855 		cifs_dbg(VFS, "blob signature incorrect %s\n",
856 			 pblob->Signature);
857 		return -EINVAL;
858 	}
859 	if (pblob->MessageType != NtLmChallenge) {
860 		cifs_dbg(VFS, "Incorrect message type %d\n",
861 			 pblob->MessageType);
862 		return -EINVAL;
863 	}
864 
865 	server_flags = le32_to_cpu(pblob->NegotiateFlags);
866 	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
867 		 ses->ntlmssp->client_flags, server_flags);
868 
869 	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
870 	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
871 		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
872 			 __func__);
873 		return -EINVAL;
874 	}
875 	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
876 		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
877 		return -EINVAL;
878 	}
879 	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
880 		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
881 			 __func__);
882 		return -EOPNOTSUPP;
883 	}
884 	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
885 	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
886 		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
887 			     __func__);
888 
889 	ses->ntlmssp->server_flags = server_flags;
890 
891 	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
892 	/* In particular we can examine sign flags */
893 	/* BB spec says that if AvId field of MsvAvTimestamp is populated then
894 		we must set the MIC field of the AUTHENTICATE_MESSAGE */
895 
896 	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
897 	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
898 	if (tioffset > blob_len || tioffset + tilen > blob_len) {
899 		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
900 			 tioffset, tilen);
901 		return -EINVAL;
902 	}
903 	if (tilen) {
904 		kfree_sensitive(ses->auth_key.response);
905 		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
906 						 GFP_KERNEL);
907 		if (!ses->auth_key.response) {
908 			cifs_dbg(VFS, "Challenge target info alloc failure\n");
909 			return -ENOMEM;
910 		}
911 		ses->auth_key.len = tilen;
912 	}
913 
914 	return 0;
915 }
916 
size_of_ntlmssp_blob(struct cifs_ses * ses,int base_size)917 static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
918 {
919 	int sz = base_size + ses->auth_key.len
920 		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
921 
922 	if (ses->domainName)
923 		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
924 	else
925 		sz += sizeof(__le16);
926 
927 	if (ses->user_name)
928 		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
929 	else
930 		sz += sizeof(__le16);
931 
932 	if (ses->workstation_name[0])
933 		sz += sizeof(__le16) * strnlen(ses->workstation_name,
934 					       ntlmssp_workstation_name_size(ses));
935 	else
936 		sz += sizeof(__le16);
937 
938 	return sz;
939 }
940 
cifs_security_buffer_from_str(SECURITY_BUFFER * pbuf,char * str_value,int str_length,unsigned char * pstart,unsigned char ** pcur,const struct nls_table * nls_cp)941 static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
942 						 char *str_value,
943 						 int str_length,
944 						 unsigned char *pstart,
945 						 unsigned char **pcur,
946 						 const struct nls_table *nls_cp)
947 {
948 	unsigned char *tmp = pstart;
949 	int len;
950 
951 	if (!pbuf)
952 		return;
953 
954 	if (!pcur)
955 		pcur = &tmp;
956 
957 	if (!str_value) {
958 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
959 		pbuf->Length = 0;
960 		pbuf->MaximumLength = 0;
961 		*pcur += sizeof(__le16);
962 	} else {
963 		len = cifs_strtoUTF16((__le16 *)*pcur,
964 				      str_value,
965 				      str_length,
966 				      nls_cp);
967 		len *= sizeof(__le16);
968 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
969 		pbuf->Length = cpu_to_le16(len);
970 		pbuf->MaximumLength = cpu_to_le16(len);
971 		*pcur += len;
972 	}
973 }
974 
975 /* BB Move to ntlmssp.c eventually */
976 
build_ntlmssp_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)977 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
978 				 u16 *buflen,
979 				 struct cifs_ses *ses,
980 				 struct TCP_Server_Info *server,
981 				 const struct nls_table *nls_cp)
982 {
983 	int rc = 0;
984 	NEGOTIATE_MESSAGE *sec_blob;
985 	__u32 flags;
986 	unsigned char *tmp;
987 	int len;
988 
989 	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
990 	*pbuffer = kmalloc(len, GFP_KERNEL);
991 	if (!*pbuffer) {
992 		rc = -ENOMEM;
993 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
994 		*buflen = 0;
995 		goto setup_ntlm_neg_ret;
996 	}
997 	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
998 
999 	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1000 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1001 	sec_blob->MessageType = NtLmNegotiate;
1002 
1003 	/* BB is NTLMV2 session security format easier to use here? */
1004 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1005 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1006 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1007 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1008 		NTLMSSP_NEGOTIATE_SIGN;
1009 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1010 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1011 
1012 	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1013 	ses->ntlmssp->client_flags = flags;
1014 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1015 
1016 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1017 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1018 				      NULL,
1019 				      CIFS_MAX_DOMAINNAME_LEN,
1020 				      *pbuffer, &tmp,
1021 				      nls_cp);
1022 
1023 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1024 				      NULL,
1025 				      CIFS_MAX_WORKSTATION_LEN,
1026 				      *pbuffer, &tmp,
1027 				      nls_cp);
1028 
1029 	*buflen = tmp - *pbuffer;
1030 setup_ntlm_neg_ret:
1031 	return rc;
1032 }
1033 
1034 /*
1035  * Build ntlmssp blob with additional fields, such as version,
1036  * supported by modern servers. For safety limit to SMB3 or later
1037  * See notes in MS-NLMP Section 2.2.2.1 e.g.
1038  */
build_ntlmssp_smb3_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1039 int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1040 				 u16 *buflen,
1041 				 struct cifs_ses *ses,
1042 				 struct TCP_Server_Info *server,
1043 				 const struct nls_table *nls_cp)
1044 {
1045 	int rc = 0;
1046 	struct negotiate_message *sec_blob;
1047 	__u32 flags;
1048 	unsigned char *tmp;
1049 	int len;
1050 
1051 	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1052 	*pbuffer = kmalloc(len, GFP_KERNEL);
1053 	if (!*pbuffer) {
1054 		rc = -ENOMEM;
1055 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1056 		*buflen = 0;
1057 		goto setup_ntlm_smb3_neg_ret;
1058 	}
1059 	sec_blob = (struct negotiate_message *)*pbuffer;
1060 
1061 	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1062 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1063 	sec_blob->MessageType = NtLmNegotiate;
1064 
1065 	/* BB is NTLMV2 session security format easier to use here? */
1066 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1067 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1068 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1069 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1070 		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1071 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1072 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1073 
1074 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1075 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1076 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1077 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1078 
1079 	tmp = *pbuffer + sizeof(struct negotiate_message);
1080 	ses->ntlmssp->client_flags = flags;
1081 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1082 
1083 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1084 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1085 				      NULL,
1086 				      CIFS_MAX_DOMAINNAME_LEN,
1087 				      *pbuffer, &tmp,
1088 				      nls_cp);
1089 
1090 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1091 				      NULL,
1092 				      CIFS_MAX_WORKSTATION_LEN,
1093 				      *pbuffer, &tmp,
1094 				      nls_cp);
1095 
1096 	*buflen = tmp - *pbuffer;
1097 setup_ntlm_smb3_neg_ret:
1098 	return rc;
1099 }
1100 
1101 
1102 /* See MS-NLMP 2.2.1.3 */
build_ntlmssp_auth_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1103 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1104 					u16 *buflen,
1105 				   struct cifs_ses *ses,
1106 				   struct TCP_Server_Info *server,
1107 				   const struct nls_table *nls_cp)
1108 {
1109 	int rc;
1110 	AUTHENTICATE_MESSAGE *sec_blob;
1111 	__u32 flags;
1112 	unsigned char *tmp;
1113 	int len;
1114 
1115 	rc = setup_ntlmv2_rsp(ses, nls_cp);
1116 	if (rc) {
1117 		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1118 		*buflen = 0;
1119 		goto setup_ntlmv2_ret;
1120 	}
1121 
1122 	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1123 	*pbuffer = kmalloc(len, GFP_KERNEL);
1124 	if (!*pbuffer) {
1125 		rc = -ENOMEM;
1126 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1127 		*buflen = 0;
1128 		goto setup_ntlmv2_ret;
1129 	}
1130 	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1131 
1132 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1133 	sec_blob->MessageType = NtLmAuthenticate;
1134 
1135 	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1136 		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1137 	/* we only send version information in ntlmssp negotiate, so do not set this flag */
1138 	flags = flags & ~NTLMSSP_NEGOTIATE_VERSION;
1139 	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1140 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1141 
1142 	sec_blob->LmChallengeResponse.BufferOffset =
1143 				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1144 	sec_blob->LmChallengeResponse.Length = 0;
1145 	sec_blob->LmChallengeResponse.MaximumLength = 0;
1146 
1147 	sec_blob->NtChallengeResponse.BufferOffset =
1148 				cpu_to_le32(tmp - *pbuffer);
1149 	if (ses->user_name != NULL) {
1150 		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1151 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1152 		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1153 
1154 		sec_blob->NtChallengeResponse.Length =
1155 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1156 		sec_blob->NtChallengeResponse.MaximumLength =
1157 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1158 	} else {
1159 		/*
1160 		 * don't send an NT Response for anonymous access
1161 		 */
1162 		sec_blob->NtChallengeResponse.Length = 0;
1163 		sec_blob->NtChallengeResponse.MaximumLength = 0;
1164 	}
1165 
1166 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1167 				      ses->domainName,
1168 				      CIFS_MAX_DOMAINNAME_LEN,
1169 				      *pbuffer, &tmp,
1170 				      nls_cp);
1171 
1172 	cifs_security_buffer_from_str(&sec_blob->UserName,
1173 				      ses->user_name,
1174 				      CIFS_MAX_USERNAME_LEN,
1175 				      *pbuffer, &tmp,
1176 				      nls_cp);
1177 
1178 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1179 				      ses->workstation_name,
1180 				      ntlmssp_workstation_name_size(ses),
1181 				      *pbuffer, &tmp,
1182 				      nls_cp);
1183 
1184 	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1185 	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1186 	    !calc_seckey(ses)) {
1187 		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1188 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1189 		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1190 		sec_blob->SessionKey.MaximumLength =
1191 				cpu_to_le16(CIFS_CPHTXT_SIZE);
1192 		tmp += CIFS_CPHTXT_SIZE;
1193 	} else {
1194 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1195 		sec_blob->SessionKey.Length = 0;
1196 		sec_blob->SessionKey.MaximumLength = 0;
1197 	}
1198 
1199 	*buflen = tmp - *pbuffer;
1200 setup_ntlmv2_ret:
1201 	return rc;
1202 }
1203 
1204 enum securityEnum
cifs_select_sectype(struct TCP_Server_Info * server,enum securityEnum requested)1205 cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1206 {
1207 	switch (server->negflavor) {
1208 	case CIFS_NEGFLAVOR_EXTENDED:
1209 		switch (requested) {
1210 		case Kerberos:
1211 		case RawNTLMSSP:
1212 			return requested;
1213 		case Unspecified:
1214 			if (server->sec_ntlmssp &&
1215 			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1216 				return RawNTLMSSP;
1217 			if ((server->sec_kerberos || server->sec_mskerberos) &&
1218 			    (global_secflags & CIFSSEC_MAY_KRB5))
1219 				return Kerberos;
1220 			fallthrough;
1221 		default:
1222 			return Unspecified;
1223 		}
1224 	case CIFS_NEGFLAVOR_UNENCAP:
1225 		switch (requested) {
1226 		case NTLMv2:
1227 			return requested;
1228 		case Unspecified:
1229 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1230 				return NTLMv2;
1231 			break;
1232 		default:
1233 			break;
1234 		}
1235 		fallthrough;
1236 	default:
1237 		return Unspecified;
1238 	}
1239 }
1240 
1241 struct sess_data {
1242 	unsigned int xid;
1243 	struct cifs_ses *ses;
1244 	struct TCP_Server_Info *server;
1245 	struct nls_table *nls_cp;
1246 	void (*func)(struct sess_data *);
1247 	int result;
1248 
1249 	/* we will send the SMB in three pieces:
1250 	 * a fixed length beginning part, an optional
1251 	 * SPNEGO blob (which can be zero length), and a
1252 	 * last part which will include the strings
1253 	 * and rest of bcc area. This allows us to avoid
1254 	 * a large buffer 17K allocation
1255 	 */
1256 	int buf0_type;
1257 	struct kvec iov[3];
1258 };
1259 
1260 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1261 static int
sess_alloc_buffer(struct sess_data * sess_data,int wct)1262 sess_alloc_buffer(struct sess_data *sess_data, int wct)
1263 {
1264 	int rc;
1265 	struct cifs_ses *ses = sess_data->ses;
1266 	struct smb_hdr *smb_buf;
1267 
1268 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1269 				  (void **)&smb_buf);
1270 
1271 	if (rc)
1272 		return rc;
1273 
1274 	sess_data->iov[0].iov_base = (char *)smb_buf;
1275 	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1276 	/*
1277 	 * This variable will be used to clear the buffer
1278 	 * allocated above in case of any error in the calling function.
1279 	 */
1280 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1281 
1282 	/* 2000 big enough to fit max user, domain, NOS name etc. */
1283 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1284 	if (!sess_data->iov[2].iov_base) {
1285 		rc = -ENOMEM;
1286 		goto out_free_smb_buf;
1287 	}
1288 
1289 	return 0;
1290 
1291 out_free_smb_buf:
1292 	cifs_small_buf_release(smb_buf);
1293 	sess_data->iov[0].iov_base = NULL;
1294 	sess_data->iov[0].iov_len = 0;
1295 	sess_data->buf0_type = CIFS_NO_BUFFER;
1296 	return rc;
1297 }
1298 
1299 static void
sess_free_buffer(struct sess_data * sess_data)1300 sess_free_buffer(struct sess_data *sess_data)
1301 {
1302 	struct kvec *iov = sess_data->iov;
1303 
1304 	/*
1305 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1306 	 * Note that iov[1] is already freed by caller.
1307 	 */
1308 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1309 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1310 
1311 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1312 	sess_data->buf0_type = CIFS_NO_BUFFER;
1313 	kfree_sensitive(iov[2].iov_base);
1314 }
1315 
1316 static int
sess_establish_session(struct sess_data * sess_data)1317 sess_establish_session(struct sess_data *sess_data)
1318 {
1319 	struct cifs_ses *ses = sess_data->ses;
1320 	struct TCP_Server_Info *server = sess_data->server;
1321 
1322 	cifs_server_lock(server);
1323 	if (!server->session_estab) {
1324 		if (server->sign) {
1325 			server->session_key.response =
1326 				kmemdup(ses->auth_key.response,
1327 				ses->auth_key.len, GFP_KERNEL);
1328 			if (!server->session_key.response) {
1329 				cifs_server_unlock(server);
1330 				return -ENOMEM;
1331 			}
1332 			server->session_key.len =
1333 						ses->auth_key.len;
1334 		}
1335 		server->sequence_number = 0x2;
1336 		server->session_estab = true;
1337 	}
1338 	cifs_server_unlock(server);
1339 
1340 	cifs_dbg(FYI, "CIFS session established successfully\n");
1341 	return 0;
1342 }
1343 
1344 static int
sess_sendreceive(struct sess_data * sess_data)1345 sess_sendreceive(struct sess_data *sess_data)
1346 {
1347 	int rc;
1348 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1349 	__u16 count;
1350 	struct kvec rsp_iov = { NULL, 0 };
1351 
1352 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1353 	be32_add_cpu(&smb_buf->smb_buf_length, count);
1354 	put_bcc(count, smb_buf);
1355 
1356 	rc = SendReceive2(sess_data->xid, sess_data->ses,
1357 			  sess_data->iov, 3 /* num_iovecs */,
1358 			  &sess_data->buf0_type,
1359 			  CIFS_LOG_ERROR, &rsp_iov);
1360 	cifs_small_buf_release(sess_data->iov[0].iov_base);
1361 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1362 
1363 	return rc;
1364 }
1365 
1366 static void
sess_auth_ntlmv2(struct sess_data * sess_data)1367 sess_auth_ntlmv2(struct sess_data *sess_data)
1368 {
1369 	int rc = 0;
1370 	struct smb_hdr *smb_buf;
1371 	SESSION_SETUP_ANDX *pSMB;
1372 	char *bcc_ptr;
1373 	struct cifs_ses *ses = sess_data->ses;
1374 	struct TCP_Server_Info *server = sess_data->server;
1375 	__u32 capabilities;
1376 	__u16 bytes_remaining;
1377 
1378 	/* old style NTLM sessionsetup */
1379 	/* wct = 13 */
1380 	rc = sess_alloc_buffer(sess_data, 13);
1381 	if (rc)
1382 		goto out;
1383 
1384 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1385 	bcc_ptr = sess_data->iov[2].iov_base;
1386 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1387 
1388 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1389 
1390 	/* LM2 password would be here if we supported it */
1391 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1392 
1393 	if (ses->user_name != NULL) {
1394 		/* calculate nlmv2 response and session key */
1395 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1396 		if (rc) {
1397 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1398 			goto out;
1399 		}
1400 
1401 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1402 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1403 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1404 
1405 		/* set case sensitive password length after tilen may get
1406 		 * assigned, tilen is 0 otherwise.
1407 		 */
1408 		pSMB->req_no_secext.CaseSensitivePasswordLength =
1409 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1410 	} else {
1411 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1412 	}
1413 
1414 	if (ses->capabilities & CAP_UNICODE) {
1415 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1416 			*bcc_ptr = 0;
1417 			bcc_ptr++;
1418 		}
1419 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1420 	} else {
1421 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1422 	}
1423 
1424 
1425 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1426 			(long) sess_data->iov[2].iov_base;
1427 
1428 	rc = sess_sendreceive(sess_data);
1429 	if (rc)
1430 		goto out;
1431 
1432 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1433 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1434 
1435 	if (smb_buf->WordCount != 3) {
1436 		rc = -EIO;
1437 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1438 		goto out;
1439 	}
1440 
1441 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1442 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1443 
1444 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1445 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1446 
1447 	bytes_remaining = get_bcc(smb_buf);
1448 	bcc_ptr = pByteArea(smb_buf);
1449 
1450 	/* BB check if Unicode and decode strings */
1451 	if (bytes_remaining == 0) {
1452 		/* no string area to decode, do nothing */
1453 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1454 		/* unicode string area must be word-aligned */
1455 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1456 			++bcc_ptr;
1457 			--bytes_remaining;
1458 		}
1459 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1460 				      sess_data->nls_cp);
1461 	} else {
1462 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1463 				    sess_data->nls_cp);
1464 	}
1465 
1466 	rc = sess_establish_session(sess_data);
1467 out:
1468 	sess_data->result = rc;
1469 	sess_data->func = NULL;
1470 	sess_free_buffer(sess_data);
1471 	kfree_sensitive(ses->auth_key.response);
1472 	ses->auth_key.response = NULL;
1473 }
1474 
1475 #ifdef CONFIG_CIFS_UPCALL
1476 static void
sess_auth_kerberos(struct sess_data * sess_data)1477 sess_auth_kerberos(struct sess_data *sess_data)
1478 {
1479 	int rc = 0;
1480 	struct smb_hdr *smb_buf;
1481 	SESSION_SETUP_ANDX *pSMB;
1482 	char *bcc_ptr;
1483 	struct cifs_ses *ses = sess_data->ses;
1484 	struct TCP_Server_Info *server = sess_data->server;
1485 	__u32 capabilities;
1486 	__u16 bytes_remaining;
1487 	struct key *spnego_key = NULL;
1488 	struct cifs_spnego_msg *msg;
1489 	u16 blob_len;
1490 
1491 	/* extended security */
1492 	/* wct = 12 */
1493 	rc = sess_alloc_buffer(sess_data, 12);
1494 	if (rc)
1495 		goto out;
1496 
1497 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1498 	bcc_ptr = sess_data->iov[2].iov_base;
1499 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1500 
1501 	spnego_key = cifs_get_spnego_key(ses, server);
1502 	if (IS_ERR(spnego_key)) {
1503 		rc = PTR_ERR(spnego_key);
1504 		spnego_key = NULL;
1505 		goto out;
1506 	}
1507 
1508 	msg = spnego_key->payload.data[0];
1509 	/*
1510 	 * check version field to make sure that cifs.upcall is
1511 	 * sending us a response in an expected form
1512 	 */
1513 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1514 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1515 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1516 		rc = -EKEYREJECTED;
1517 		goto out_put_spnego_key;
1518 	}
1519 
1520 	kfree_sensitive(ses->auth_key.response);
1521 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1522 					 GFP_KERNEL);
1523 	if (!ses->auth_key.response) {
1524 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1525 			 msg->sesskey_len);
1526 		rc = -ENOMEM;
1527 		goto out_put_spnego_key;
1528 	}
1529 	ses->auth_key.len = msg->sesskey_len;
1530 
1531 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1532 	capabilities |= CAP_EXTENDED_SECURITY;
1533 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1534 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1535 	sess_data->iov[1].iov_len = msg->secblob_len;
1536 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1537 
1538 	if (ses->capabilities & CAP_UNICODE) {
1539 		/* unicode strings must be word aligned */
1540 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1541 			*bcc_ptr = 0;
1542 			bcc_ptr++;
1543 		}
1544 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1545 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1546 	} else {
1547 		/* BB: is this right? */
1548 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1549 	}
1550 
1551 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1552 			(long) sess_data->iov[2].iov_base;
1553 
1554 	rc = sess_sendreceive(sess_data);
1555 	if (rc)
1556 		goto out_put_spnego_key;
1557 
1558 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1559 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1560 
1561 	if (smb_buf->WordCount != 4) {
1562 		rc = -EIO;
1563 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1564 		goto out_put_spnego_key;
1565 	}
1566 
1567 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1568 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1569 
1570 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1571 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1572 
1573 	bytes_remaining = get_bcc(smb_buf);
1574 	bcc_ptr = pByteArea(smb_buf);
1575 
1576 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1577 	if (blob_len > bytes_remaining) {
1578 		cifs_dbg(VFS, "bad security blob length %d\n",
1579 				blob_len);
1580 		rc = -EINVAL;
1581 		goto out_put_spnego_key;
1582 	}
1583 	bcc_ptr += blob_len;
1584 	bytes_remaining -= blob_len;
1585 
1586 	/* BB check if Unicode and decode strings */
1587 	if (bytes_remaining == 0) {
1588 		/* no string area to decode, do nothing */
1589 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1590 		/* unicode string area must be word-aligned */
1591 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1592 			++bcc_ptr;
1593 			--bytes_remaining;
1594 		}
1595 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1596 				      sess_data->nls_cp);
1597 	} else {
1598 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1599 				    sess_data->nls_cp);
1600 	}
1601 
1602 	rc = sess_establish_session(sess_data);
1603 out_put_spnego_key:
1604 	key_invalidate(spnego_key);
1605 	key_put(spnego_key);
1606 out:
1607 	sess_data->result = rc;
1608 	sess_data->func = NULL;
1609 	sess_free_buffer(sess_data);
1610 	kfree_sensitive(ses->auth_key.response);
1611 	ses->auth_key.response = NULL;
1612 }
1613 
1614 #endif /* ! CONFIG_CIFS_UPCALL */
1615 
1616 /*
1617  * The required kvec buffers have to be allocated before calling this
1618  * function.
1619  */
1620 static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data * sess_data)1621 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1622 {
1623 	SESSION_SETUP_ANDX *pSMB;
1624 	struct cifs_ses *ses = sess_data->ses;
1625 	struct TCP_Server_Info *server = sess_data->server;
1626 	__u32 capabilities;
1627 	char *bcc_ptr;
1628 
1629 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1630 
1631 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1632 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1633 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1634 		return -ENOSYS;
1635 	}
1636 
1637 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1638 	capabilities |= CAP_EXTENDED_SECURITY;
1639 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1640 
1641 	bcc_ptr = sess_data->iov[2].iov_base;
1642 	/* unicode strings must be word aligned */
1643 	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1644 		*bcc_ptr = 0;
1645 		bcc_ptr++;
1646 	}
1647 	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1648 
1649 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1650 					(long) sess_data->iov[2].iov_base;
1651 
1652 	return 0;
1653 }
1654 
1655 static void
1656 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1657 
1658 static void
sess_auth_rawntlmssp_negotiate(struct sess_data * sess_data)1659 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1660 {
1661 	int rc;
1662 	struct smb_hdr *smb_buf;
1663 	SESSION_SETUP_ANDX *pSMB;
1664 	struct cifs_ses *ses = sess_data->ses;
1665 	struct TCP_Server_Info *server = sess_data->server;
1666 	__u16 bytes_remaining;
1667 	char *bcc_ptr;
1668 	unsigned char *ntlmsspblob = NULL;
1669 	u16 blob_len;
1670 
1671 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1672 
1673 	/*
1674 	 * if memory allocation is successful, caller of this function
1675 	 * frees it.
1676 	 */
1677 	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1678 	if (!ses->ntlmssp) {
1679 		rc = -ENOMEM;
1680 		goto out;
1681 	}
1682 	ses->ntlmssp->sesskey_per_smbsess = false;
1683 
1684 	/* wct = 12 */
1685 	rc = sess_alloc_buffer(sess_data, 12);
1686 	if (rc)
1687 		goto out;
1688 
1689 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1690 
1691 	/* Build security blob before we assemble the request */
1692 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1693 				     &blob_len, ses, server,
1694 				     sess_data->nls_cp);
1695 	if (rc)
1696 		goto out_free_ntlmsspblob;
1697 
1698 	sess_data->iov[1].iov_len = blob_len;
1699 	sess_data->iov[1].iov_base = ntlmsspblob;
1700 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1701 
1702 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1703 	if (rc)
1704 		goto out_free_ntlmsspblob;
1705 
1706 	rc = sess_sendreceive(sess_data);
1707 
1708 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1709 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1710 
1711 	/* If true, rc here is expected and not an error */
1712 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1713 	    smb_buf->Status.CifsError ==
1714 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1715 		rc = 0;
1716 
1717 	if (rc)
1718 		goto out_free_ntlmsspblob;
1719 
1720 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1721 
1722 	if (smb_buf->WordCount != 4) {
1723 		rc = -EIO;
1724 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1725 		goto out_free_ntlmsspblob;
1726 	}
1727 
1728 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1729 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1730 
1731 	bytes_remaining = get_bcc(smb_buf);
1732 	bcc_ptr = pByteArea(smb_buf);
1733 
1734 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1735 	if (blob_len > bytes_remaining) {
1736 		cifs_dbg(VFS, "bad security blob length %d\n",
1737 				blob_len);
1738 		rc = -EINVAL;
1739 		goto out_free_ntlmsspblob;
1740 	}
1741 
1742 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1743 
1744 out_free_ntlmsspblob:
1745 	kfree_sensitive(ntlmsspblob);
1746 out:
1747 	sess_free_buffer(sess_data);
1748 
1749 	if (!rc) {
1750 		sess_data->func = sess_auth_rawntlmssp_authenticate;
1751 		return;
1752 	}
1753 
1754 	/* Else error. Cleanup */
1755 	kfree_sensitive(ses->auth_key.response);
1756 	ses->auth_key.response = NULL;
1757 	kfree_sensitive(ses->ntlmssp);
1758 	ses->ntlmssp = NULL;
1759 
1760 	sess_data->func = NULL;
1761 	sess_data->result = rc;
1762 }
1763 
1764 static void
sess_auth_rawntlmssp_authenticate(struct sess_data * sess_data)1765 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1766 {
1767 	int rc;
1768 	struct smb_hdr *smb_buf;
1769 	SESSION_SETUP_ANDX *pSMB;
1770 	struct cifs_ses *ses = sess_data->ses;
1771 	struct TCP_Server_Info *server = sess_data->server;
1772 	__u16 bytes_remaining;
1773 	char *bcc_ptr;
1774 	unsigned char *ntlmsspblob = NULL;
1775 	u16 blob_len;
1776 
1777 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1778 
1779 	/* wct = 12 */
1780 	rc = sess_alloc_buffer(sess_data, 12);
1781 	if (rc)
1782 		goto out;
1783 
1784 	/* Build security blob before we assemble the request */
1785 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1786 	smb_buf = (struct smb_hdr *)pSMB;
1787 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1788 					&blob_len, ses, server,
1789 					sess_data->nls_cp);
1790 	if (rc)
1791 		goto out_free_ntlmsspblob;
1792 	sess_data->iov[1].iov_len = blob_len;
1793 	sess_data->iov[1].iov_base = ntlmsspblob;
1794 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1795 	/*
1796 	 * Make sure that we tell the server that we are using
1797 	 * the uid that it just gave us back on the response
1798 	 * (challenge)
1799 	 */
1800 	smb_buf->Uid = ses->Suid;
1801 
1802 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1803 	if (rc)
1804 		goto out_free_ntlmsspblob;
1805 
1806 	rc = sess_sendreceive(sess_data);
1807 	if (rc)
1808 		goto out_free_ntlmsspblob;
1809 
1810 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1811 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1812 	if (smb_buf->WordCount != 4) {
1813 		rc = -EIO;
1814 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1815 		goto out_free_ntlmsspblob;
1816 	}
1817 
1818 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1819 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1820 
1821 	if (ses->Suid != smb_buf->Uid) {
1822 		ses->Suid = smb_buf->Uid;
1823 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1824 	}
1825 
1826 	bytes_remaining = get_bcc(smb_buf);
1827 	bcc_ptr = pByteArea(smb_buf);
1828 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1829 	if (blob_len > bytes_remaining) {
1830 		cifs_dbg(VFS, "bad security blob length %d\n",
1831 				blob_len);
1832 		rc = -EINVAL;
1833 		goto out_free_ntlmsspblob;
1834 	}
1835 	bcc_ptr += blob_len;
1836 	bytes_remaining -= blob_len;
1837 
1838 
1839 	/* BB check if Unicode and decode strings */
1840 	if (bytes_remaining == 0) {
1841 		/* no string area to decode, do nothing */
1842 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1843 		/* unicode string area must be word-aligned */
1844 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1845 			++bcc_ptr;
1846 			--bytes_remaining;
1847 		}
1848 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1849 				      sess_data->nls_cp);
1850 	} else {
1851 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1852 				    sess_data->nls_cp);
1853 	}
1854 
1855 out_free_ntlmsspblob:
1856 	kfree_sensitive(ntlmsspblob);
1857 out:
1858 	sess_free_buffer(sess_data);
1859 
1860 	if (!rc)
1861 		rc = sess_establish_session(sess_data);
1862 
1863 	/* Cleanup */
1864 	kfree_sensitive(ses->auth_key.response);
1865 	ses->auth_key.response = NULL;
1866 	kfree_sensitive(ses->ntlmssp);
1867 	ses->ntlmssp = NULL;
1868 
1869 	sess_data->func = NULL;
1870 	sess_data->result = rc;
1871 }
1872 
select_sec(struct sess_data * sess_data)1873 static int select_sec(struct sess_data *sess_data)
1874 {
1875 	int type;
1876 	struct cifs_ses *ses = sess_data->ses;
1877 	struct TCP_Server_Info *server = sess_data->server;
1878 
1879 	type = cifs_select_sectype(server, ses->sectype);
1880 	cifs_dbg(FYI, "sess setup type %d\n", type);
1881 	if (type == Unspecified) {
1882 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1883 		return -EINVAL;
1884 	}
1885 
1886 	switch (type) {
1887 	case NTLMv2:
1888 		sess_data->func = sess_auth_ntlmv2;
1889 		break;
1890 	case Kerberos:
1891 #ifdef CONFIG_CIFS_UPCALL
1892 		sess_data->func = sess_auth_kerberos;
1893 		break;
1894 #else
1895 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
1896 		return -ENOSYS;
1897 #endif /* CONFIG_CIFS_UPCALL */
1898 	case RawNTLMSSP:
1899 		sess_data->func = sess_auth_rawntlmssp_negotiate;
1900 		break;
1901 	default:
1902 		cifs_dbg(VFS, "secType %d not supported!\n", type);
1903 		return -ENOSYS;
1904 	}
1905 
1906 	return 0;
1907 }
1908 
CIFS_SessSetup(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1909 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
1910 		   struct TCP_Server_Info *server,
1911 		   const struct nls_table *nls_cp)
1912 {
1913 	int rc = 0;
1914 	struct sess_data *sess_data;
1915 
1916 	if (ses == NULL) {
1917 		WARN(1, "%s: ses == NULL!", __func__);
1918 		return -EINVAL;
1919 	}
1920 
1921 	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
1922 	if (!sess_data)
1923 		return -ENOMEM;
1924 
1925 	sess_data->xid = xid;
1926 	sess_data->ses = ses;
1927 	sess_data->server = server;
1928 	sess_data->buf0_type = CIFS_NO_BUFFER;
1929 	sess_data->nls_cp = (struct nls_table *) nls_cp;
1930 
1931 	rc = select_sec(sess_data);
1932 	if (rc)
1933 		goto out;
1934 
1935 	while (sess_data->func)
1936 		sess_data->func(sess_data);
1937 
1938 	/* Store result before we free sess_data */
1939 	rc = sess_data->result;
1940 
1941 out:
1942 	kfree_sensitive(sess_data);
1943 	return rc;
1944 }
1945 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
1946