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_ses *ses,
28 		     struct cifs_server_iface *iface);
29 
is_ses_using_iface(struct cifs_ses * ses,struct cifs_server_iface * iface)30 bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
31 {
32 	int i;
33 
34 	spin_lock(&ses->chan_lock);
35 	for (i = 0; i < ses->chan_count; i++) {
36 		if (ses->chans[i].iface == iface) {
37 			spin_unlock(&ses->chan_lock);
38 			return true;
39 		}
40 	}
41 	spin_unlock(&ses->chan_lock);
42 	return false;
43 }
44 
45 /* channel helper functions. assumed that chan_lock is held by caller. */
46 
47 int
cifs_ses_get_chan_index(struct cifs_ses * ses,struct TCP_Server_Info * server)48 cifs_ses_get_chan_index(struct cifs_ses *ses,
49 			struct TCP_Server_Info *server)
50 {
51 	unsigned int i;
52 
53 	/* if the channel is waiting for termination */
54 	if (server && server->terminate)
55 		return CIFS_INVAL_CHAN_INDEX;
56 
57 	for (i = 0; i < ses->chan_count; i++) {
58 		if (ses->chans[i].server == server)
59 			return i;
60 	}
61 
62 	/* If we didn't find the channel, it is likely a bug */
63 	if (server)
64 		cifs_dbg(VFS, "unable to get chan index for server: 0x%llx",
65 			 server->conn_id);
66 	return CIFS_INVAL_CHAN_INDEX;
67 }
68 
69 void
cifs_chan_set_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)70 cifs_chan_set_in_reconnect(struct cifs_ses *ses,
71 			     struct TCP_Server_Info *server)
72 {
73 	int chan_index = cifs_ses_get_chan_index(ses, server);
74 
75 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
76 		return;
77 
78 	ses->chans[chan_index].in_reconnect = true;
79 }
80 
81 void
cifs_chan_clear_in_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)82 cifs_chan_clear_in_reconnect(struct cifs_ses *ses,
83 			     struct TCP_Server_Info *server)
84 {
85 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
86 
87 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
88 		return;
89 
90 	ses->chans[chan_index].in_reconnect = false;
91 }
92 
93 void
cifs_chan_set_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)94 cifs_chan_set_need_reconnect(struct cifs_ses *ses,
95 			     struct TCP_Server_Info *server)
96 {
97 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
98 
99 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
100 		return;
101 
102 	set_bit(chan_index, &ses->chans_need_reconnect);
103 	cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n",
104 		 chan_index, ses->chans_need_reconnect);
105 }
106 
107 void
cifs_chan_clear_need_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)108 cifs_chan_clear_need_reconnect(struct cifs_ses *ses,
109 			       struct TCP_Server_Info *server)
110 {
111 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
112 
113 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
114 		return;
115 
116 	clear_bit(chan_index, &ses->chans_need_reconnect);
117 	cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n",
118 		 chan_index, ses->chans_need_reconnect);
119 }
120 
121 bool
cifs_chan_needs_reconnect(struct cifs_ses * ses,struct TCP_Server_Info * server)122 cifs_chan_needs_reconnect(struct cifs_ses *ses,
123 			  struct TCP_Server_Info *server)
124 {
125 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
126 
127 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
128 		return true;	/* err on the safer side */
129 
130 	return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index);
131 }
132 
133 bool
cifs_chan_is_iface_active(struct cifs_ses * ses,struct TCP_Server_Info * server)134 cifs_chan_is_iface_active(struct cifs_ses *ses,
135 			  struct TCP_Server_Info *server)
136 {
137 	unsigned int chan_index = cifs_ses_get_chan_index(ses, server);
138 
139 	if (chan_index == CIFS_INVAL_CHAN_INDEX)
140 		return true;	/* err on the safer side */
141 
142 	return ses->chans[chan_index].iface &&
143 		ses->chans[chan_index].iface->is_active;
144 }
145 
146 /* returns number of channels added */
cifs_try_adding_channels(struct cifs_ses * ses)147 int cifs_try_adding_channels(struct cifs_ses *ses)
148 {
149 	struct TCP_Server_Info *server = ses->server;
150 	int old_chan_count, new_chan_count;
151 	int left;
152 	int rc = 0;
153 	int tries = 0;
154 	size_t iface_weight = 0, iface_min_speed = 0;
155 	struct cifs_server_iface *iface = NULL, *niface = NULL;
156 	struct cifs_server_iface *last_iface = NULL;
157 
158 	spin_lock(&ses->chan_lock);
159 
160 	new_chan_count = old_chan_count = ses->chan_count;
161 	left = ses->chan_max - ses->chan_count;
162 
163 	if (left <= 0) {
164 		spin_unlock(&ses->chan_lock);
165 		cifs_dbg(FYI,
166 			 "ses already at max_channels (%zu), nothing to open\n",
167 			 ses->chan_max);
168 		return 0;
169 	}
170 
171 	if (server->dialect < SMB30_PROT_ID) {
172 		spin_unlock(&ses->chan_lock);
173 		cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
174 		return 0;
175 	}
176 
177 	if (!(server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
178 		spin_unlock(&ses->chan_lock);
179 		cifs_server_dbg(VFS, "no multichannel support\n");
180 		return 0;
181 	}
182 	spin_unlock(&ses->chan_lock);
183 
184 	while (left > 0) {
185 
186 		tries++;
187 		if (tries > 3*ses->chan_max) {
188 			cifs_dbg(VFS, "too many channel open attempts (%d channels left to open)\n",
189 				 left);
190 			break;
191 		}
192 
193 		spin_lock(&ses->iface_lock);
194 		if (!ses->iface_count) {
195 			spin_unlock(&ses->iface_lock);
196 			cifs_dbg(ONCE, "server %s does not advertise interfaces\n",
197 				      ses->server->hostname);
198 			break;
199 		}
200 
201 		if (!iface)
202 			iface = list_first_entry(&ses->iface_list, struct cifs_server_iface,
203 						 iface_head);
204 		last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
205 					     iface_head);
206 		iface_min_speed = last_iface->speed;
207 
208 		list_for_each_entry_safe_from(iface, niface, &ses->iface_list,
209 				    iface_head) {
210 			/* do not mix rdma and non-rdma interfaces */
211 			if (iface->rdma_capable != ses->server->rdma)
212 				continue;
213 
214 			/* skip ifaces that are unusable */
215 			if (!iface->is_active ||
216 			    (is_ses_using_iface(ses, iface) &&
217 			     !iface->rss_capable))
218 				continue;
219 
220 			/* check if we already allocated enough channels */
221 			iface_weight = iface->speed / iface_min_speed;
222 
223 			if (iface->weight_fulfilled >= iface_weight)
224 				continue;
225 
226 			/* take ref before unlock */
227 			kref_get(&iface->refcount);
228 
229 			spin_unlock(&ses->iface_lock);
230 			rc = cifs_ses_add_channel(ses, iface);
231 			spin_lock(&ses->iface_lock);
232 
233 			if (rc) {
234 				cifs_dbg(VFS, "failed to open extra channel on iface:%pIS rc=%d\n",
235 					 &iface->sockaddr,
236 					 rc);
237 				kref_put(&iface->refcount, release_iface);
238 				/* failure to add chan should increase weight */
239 				iface->weight_fulfilled++;
240 				continue;
241 			}
242 
243 			iface->num_channels++;
244 			iface->weight_fulfilled++;
245 			cifs_info("successfully opened new channel on iface:%pIS\n",
246 				 &iface->sockaddr);
247 			break;
248 		}
249 
250 		/* reached end of list. reset weight_fulfilled and start over */
251 		if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
252 			list_for_each_entry(iface, &ses->iface_list, iface_head)
253 				iface->weight_fulfilled = 0;
254 			spin_unlock(&ses->iface_lock);
255 			iface = NULL;
256 			continue;
257 		}
258 		spin_unlock(&ses->iface_lock);
259 
260 		left--;
261 		new_chan_count++;
262 	}
263 
264 	return new_chan_count - old_chan_count;
265 }
266 
267 /*
268  * called when multichannel is disabled by the server.
269  * this always gets called from smb2_reconnect
270  * and cannot get called in parallel threads.
271  */
272 void
cifs_disable_secondary_channels(struct cifs_ses * ses)273 cifs_disable_secondary_channels(struct cifs_ses *ses)
274 {
275 	int i, chan_count;
276 	struct TCP_Server_Info *server;
277 	struct cifs_server_iface *iface;
278 
279 	spin_lock(&ses->chan_lock);
280 	chan_count = ses->chan_count;
281 	if (chan_count == 1)
282 		goto done;
283 
284 	ses->chan_count = 1;
285 
286 	/* for all secondary channels reset the need reconnect bit */
287 	ses->chans_need_reconnect &= 1;
288 
289 	for (i = 1; i < chan_count; i++) {
290 		iface = ses->chans[i].iface;
291 		server = ses->chans[i].server;
292 
293 		/*
294 		 * remove these references first, since we need to unlock
295 		 * the chan_lock here, since iface_lock is a higher lock
296 		 */
297 		ses->chans[i].iface = NULL;
298 		ses->chans[i].server = NULL;
299 		spin_unlock(&ses->chan_lock);
300 
301 		if (iface) {
302 			spin_lock(&ses->iface_lock);
303 			iface->num_channels--;
304 			if (iface->weight_fulfilled)
305 				iface->weight_fulfilled--;
306 			kref_put(&iface->refcount, release_iface);
307 			spin_unlock(&ses->iface_lock);
308 		}
309 
310 		if (server) {
311 			if (!server->terminate) {
312 				server->terminate = true;
313 				cifs_signal_cifsd_for_reconnect(server, false);
314 			}
315 			cifs_put_tcp_session(server, false);
316 		}
317 
318 		spin_lock(&ses->chan_lock);
319 	}
320 
321 done:
322 	spin_unlock(&ses->chan_lock);
323 }
324 
325 /* update the iface for the channel if necessary. */
326 void
cifs_chan_update_iface(struct cifs_ses * ses,struct TCP_Server_Info * server)327 cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server)
328 {
329 	unsigned int chan_index;
330 	size_t iface_weight = 0, iface_min_speed = 0;
331 	struct cifs_server_iface *iface = NULL;
332 	struct cifs_server_iface *old_iface = NULL;
333 	struct cifs_server_iface *last_iface = NULL;
334 	struct sockaddr_storage ss;
335 
336 	spin_lock(&ses->chan_lock);
337 	chan_index = cifs_ses_get_chan_index(ses, server);
338 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
339 		spin_unlock(&ses->chan_lock);
340 		return;
341 	}
342 
343 	if (ses->chans[chan_index].iface) {
344 		old_iface = ses->chans[chan_index].iface;
345 		if (old_iface->is_active) {
346 			spin_unlock(&ses->chan_lock);
347 			return;
348 		}
349 	}
350 	spin_unlock(&ses->chan_lock);
351 
352 	spin_lock(&server->srv_lock);
353 	ss = server->dstaddr;
354 	spin_unlock(&server->srv_lock);
355 
356 	spin_lock(&ses->iface_lock);
357 	if (!ses->iface_count) {
358 		spin_unlock(&ses->iface_lock);
359 		cifs_dbg(ONCE, "server %s does not advertise interfaces\n", ses->server->hostname);
360 		return;
361 	}
362 
363 	last_iface = list_last_entry(&ses->iface_list, struct cifs_server_iface,
364 				     iface_head);
365 	iface_min_speed = last_iface->speed;
366 
367 	/* then look for a new one */
368 	list_for_each_entry(iface, &ses->iface_list, iface_head) {
369 		if (!chan_index) {
370 			/* if we're trying to get the updated iface for primary channel */
371 			if (!cifs_match_ipaddr((struct sockaddr *) &ss,
372 					       (struct sockaddr *) &iface->sockaddr))
373 				continue;
374 
375 			kref_get(&iface->refcount);
376 			break;
377 		}
378 
379 		/* do not mix rdma and non-rdma interfaces */
380 		if (iface->rdma_capable != server->rdma)
381 			continue;
382 
383 		if (!iface->is_active ||
384 		    (is_ses_using_iface(ses, iface) &&
385 		     !iface->rss_capable)) {
386 			continue;
387 		}
388 
389 		/* check if we already allocated enough channels */
390 		iface_weight = iface->speed / iface_min_speed;
391 
392 		if (iface->weight_fulfilled >= iface_weight)
393 			continue;
394 
395 		kref_get(&iface->refcount);
396 		break;
397 	}
398 
399 	if (list_entry_is_head(iface, &ses->iface_list, iface_head)) {
400 		iface = NULL;
401 		cifs_dbg(FYI, "unable to find a suitable iface\n");
402 	}
403 
404 	if (!iface) {
405 		if (!chan_index)
406 			cifs_dbg(FYI, "unable to get the interface matching: %pIS\n",
407 				 &ss);
408 		else {
409 			cifs_dbg(FYI, "unable to find another interface to replace: %pIS\n",
410 				 &old_iface->sockaddr);
411 		}
412 
413 		spin_unlock(&ses->iface_lock);
414 		return;
415 	}
416 
417 	/* now drop the ref to the current iface */
418 	if (old_iface) {
419 		cifs_dbg(FYI, "replacing iface: %pIS with %pIS\n",
420 			 &old_iface->sockaddr,
421 			 &iface->sockaddr);
422 
423 		old_iface->num_channels--;
424 		if (old_iface->weight_fulfilled)
425 			old_iface->weight_fulfilled--;
426 		iface->num_channels++;
427 		iface->weight_fulfilled++;
428 
429 		kref_put(&old_iface->refcount, release_iface);
430 	} else if (!chan_index) {
431 		/* special case: update interface for primary channel */
432 		cifs_dbg(FYI, "referencing primary channel iface: %pIS\n",
433 			 &iface->sockaddr);
434 		iface->num_channels++;
435 		iface->weight_fulfilled++;
436 	}
437 	spin_unlock(&ses->iface_lock);
438 
439 	spin_lock(&ses->chan_lock);
440 	chan_index = cifs_ses_get_chan_index(ses, server);
441 	if (chan_index == CIFS_INVAL_CHAN_INDEX) {
442 		spin_unlock(&ses->chan_lock);
443 		return;
444 	}
445 
446 	ses->chans[chan_index].iface = iface;
447 	spin_unlock(&ses->chan_lock);
448 }
449 
450 static int
cifs_ses_add_channel(struct cifs_ses * ses,struct cifs_server_iface * iface)451 cifs_ses_add_channel(struct cifs_ses *ses,
452 		     struct cifs_server_iface *iface)
453 {
454 	struct TCP_Server_Info *chan_server;
455 	struct cifs_chan *chan;
456 	struct smb3_fs_context *ctx;
457 	static const char unc_fmt[] = "\\%s\\foo";
458 	struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
459 	struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
460 	size_t len;
461 	int rc;
462 	unsigned int xid = get_xid();
463 
464 	if (iface->sockaddr.ss_family == AF_INET)
465 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
466 			 ses, iface->speed, str_yes_no(iface->rdma_capable),
467 			 &ipv4->sin_addr);
468 	else
469 		cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI6)\n",
470 			 ses, iface->speed, str_yes_no(iface->rdma_capable),
471 			 &ipv6->sin6_addr);
472 
473 	/*
474 	 * Setup a ctx with mostly the same info as the existing
475 	 * session and overwrite it with the requested iface data.
476 	 *
477 	 * We need to setup at least the fields used for negprot and
478 	 * sesssetup.
479 	 *
480 	 * We only need the ctx here, so we can reuse memory from
481 	 * the session and server without caring about memory
482 	 * management.
483 	 */
484 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
485 	if (!ctx) {
486 		rc = -ENOMEM;
487 		goto out_free_xid;
488 	}
489 
490 	/* Always make new connection for now (TODO?) */
491 	ctx->nosharesock = true;
492 
493 	/* Auth */
494 	ctx->domainauto = ses->domainAuto;
495 	ctx->domainname = ses->domainName;
496 
497 	/* no hostname for extra channels */
498 	ctx->server_hostname = "";
499 
500 	ctx->username = ses->user_name;
501 	ctx->password = ses->password;
502 	ctx->sectype = ses->sectype;
503 	ctx->sign = ses->sign;
504 	ctx->unicode = ses->unicode;
505 
506 	/* UNC and paths */
507 	/* XXX: Use ses->server->hostname? */
508 	len = sizeof(unc_fmt) + SERVER_NAME_LEN_WITH_NULL;
509 	ctx->UNC = kzalloc(len, GFP_KERNEL);
510 	if (!ctx->UNC) {
511 		rc = -ENOMEM;
512 		goto out_free_ctx;
513 	}
514 	scnprintf(ctx->UNC, len, unc_fmt, ses->ip_addr);
515 	ctx->prepath = "";
516 
517 	/* Reuse same version as master connection */
518 	ctx->vals = ses->server->vals;
519 	ctx->ops = ses->server->ops;
520 
521 	ctx->noblocksnd = ses->server->noblocksnd;
522 	ctx->noautotune = ses->server->noautotune;
523 	ctx->sockopt_tcp_nodelay = ses->server->tcp_nodelay;
524 	ctx->echo_interval = ses->server->echo_interval / HZ;
525 	ctx->max_credits = ses->server->max_credits;
526 	ctx->min_offload = ses->server->min_offload;
527 	ctx->compress = ses->server->compression.requested;
528 	ctx->dfs_conn = ses->server->dfs_conn;
529 	ctx->ignore_signature = ses->server->ignore_signature;
530 	ctx->leaf_fullpath = ses->server->leaf_fullpath;
531 	ctx->rootfs = ses->server->noblockcnt;
532 	ctx->retrans = ses->server->retrans;
533 
534 	/*
535 	 * This will be used for encoding/decoding user/domain/pw
536 	 * during sess setup auth.
537 	 */
538 	ctx->local_nls = ses->local_nls;
539 
540 	/* Use RDMA if possible */
541 	ctx->rdma = iface->rdma_capable;
542 	memcpy(&ctx->dstaddr, &iface->sockaddr, sizeof(ctx->dstaddr));
543 
544 	/* reuse master con client guid */
545 	memcpy(&ctx->client_guid, ses->server->client_guid,
546 	       sizeof(ctx->client_guid));
547 	ctx->use_client_guid = true;
548 
549 	chan_server = cifs_get_tcp_session(ctx, ses->server);
550 
551 	spin_lock(&ses->chan_lock);
552 	chan = &ses->chans[ses->chan_count];
553 	chan->server = chan_server;
554 	if (IS_ERR(chan->server)) {
555 		rc = PTR_ERR(chan->server);
556 		chan->server = NULL;
557 		spin_unlock(&ses->chan_lock);
558 		goto out;
559 	}
560 	chan->iface = iface;
561 	ses->chan_count++;
562 	atomic_set(&ses->chan_seq, 0);
563 
564 	/* Mark this channel as needing connect/setup */
565 	cifs_chan_set_need_reconnect(ses, chan->server);
566 
567 	spin_unlock(&ses->chan_lock);
568 
569 	mutex_lock(&ses->session_mutex);
570 	/*
571 	 * We need to allocate the server crypto now as we will need
572 	 * to sign packets before we generate the channel signing key
573 	 * (we sign with the session key)
574 	 */
575 	rc = smb311_crypto_shash_allocate(chan->server);
576 	if (rc) {
577 		cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
578 		mutex_unlock(&ses->session_mutex);
579 		goto out;
580 	}
581 
582 	rc = cifs_negotiate_protocol(xid, ses, chan->server);
583 	if (!rc)
584 		rc = cifs_setup_session(xid, ses, chan->server, ses->local_nls);
585 
586 	mutex_unlock(&ses->session_mutex);
587 
588 out:
589 	if (rc && chan->server) {
590 		cifs_put_tcp_session(chan->server, 0);
591 
592 		spin_lock(&ses->chan_lock);
593 
594 		/* we rely on all bits beyond chan_count to be clear */
595 		cifs_chan_clear_need_reconnect(ses, chan->server);
596 		ses->chan_count--;
597 		/*
598 		 * chan_count should never reach 0 as at least the primary
599 		 * channel is always allocated
600 		 */
601 		WARN_ON(ses->chan_count < 1);
602 		spin_unlock(&ses->chan_lock);
603 	}
604 
605 	kfree(ctx->UNC);
606 out_free_ctx:
607 	kfree(ctx);
608 out_free_xid:
609 	free_xid(xid);
610 	return rc;
611 }
612 
613 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
cifs_ssetup_hdr(struct cifs_ses * ses,struct TCP_Server_Info * server,SESSION_SETUP_ANDX * pSMB)614 static __u32 cifs_ssetup_hdr(struct cifs_ses *ses,
615 			     struct TCP_Server_Info *server,
616 			     SESSION_SETUP_ANDX *pSMB)
617 {
618 	__u32 capabilities = 0;
619 
620 	/* init fields common to all four types of SessSetup */
621 	/* Note that offsets for first seven fields in req struct are same  */
622 	/*	in CIFS Specs so does not matter which of 3 forms of struct */
623 	/*	that we use in next few lines                               */
624 	/* Note that header is initialized to zero in header_assemble */
625 	pSMB->req.AndXCommand = 0xFF;
626 	pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
627 					CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
628 					USHRT_MAX));
629 	pSMB->req.MaxMpxCount = cpu_to_le16(server->maxReq);
630 	pSMB->req.VcNumber = cpu_to_le16(1);
631 
632 	/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
633 
634 	/* BB verify whether signing required on neg or just auth frame (and NTLM case) */
635 
636 	capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
637 			CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
638 
639 	if (server->sign)
640 		pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
641 
642 	if (ses->capabilities & CAP_UNICODE) {
643 		pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
644 		capabilities |= CAP_UNICODE;
645 	}
646 	if (ses->capabilities & CAP_STATUS32) {
647 		pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
648 		capabilities |= CAP_STATUS32;
649 	}
650 	if (ses->capabilities & CAP_DFS) {
651 		pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
652 		capabilities |= CAP_DFS;
653 	}
654 	if (ses->capabilities & CAP_UNIX)
655 		capabilities |= CAP_UNIX;
656 
657 	return capabilities;
658 }
659 
660 static void
unicode_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)661 unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
662 {
663 	char *bcc_ptr = *pbcc_area;
664 	int bytes_ret = 0;
665 
666 	/* Copy OS version */
667 	bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
668 				    nls_cp);
669 	bcc_ptr += 2 * bytes_ret;
670 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
671 				    32, nls_cp);
672 	bcc_ptr += 2 * bytes_ret;
673 	bcc_ptr += 2; /* trailing null */
674 
675 	bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
676 				    32, nls_cp);
677 	bcc_ptr += 2 * bytes_ret;
678 	bcc_ptr += 2; /* trailing null */
679 
680 	*pbcc_area = bcc_ptr;
681 }
682 
683 static void
ascii_oslm_strings(char ** pbcc_area,const struct nls_table * nls_cp)684 ascii_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
685 {
686 	char *bcc_ptr = *pbcc_area;
687 
688 	strcpy(bcc_ptr, "Linux version ");
689 	bcc_ptr += strlen("Linux version ");
690 	strcpy(bcc_ptr, init_utsname()->release);
691 	bcc_ptr += strlen(init_utsname()->release) + 1;
692 
693 	strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
694 	bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
695 
696 	*pbcc_area = bcc_ptr;
697 }
698 
unicode_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)699 static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
700 				   const struct nls_table *nls_cp)
701 {
702 	char *bcc_ptr = *pbcc_area;
703 	int bytes_ret = 0;
704 
705 	/* copy domain */
706 	if (ses->domainName == NULL) {
707 		/*
708 		 * Sending null domain better than using a bogus domain name (as
709 		 * we did briefly in 2.6.18) since server will use its default
710 		 */
711 		*bcc_ptr = 0;
712 		*(bcc_ptr+1) = 0;
713 		bytes_ret = 0;
714 	} else
715 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
716 					    CIFS_MAX_DOMAINNAME_LEN, nls_cp);
717 	bcc_ptr += 2 * bytes_ret;
718 	bcc_ptr += 2;  /* account for null terminator */
719 
720 	*pbcc_area = bcc_ptr;
721 }
722 
ascii_domain_string(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)723 static void ascii_domain_string(char **pbcc_area, struct cifs_ses *ses,
724 				const struct nls_table *nls_cp)
725 {
726 	char *bcc_ptr = *pbcc_area;
727 	int len;
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 send a null domain name so server will default to its own domain */
736 	*bcc_ptr = 0;
737 	bcc_ptr++;
738 
739 	*pbcc_area = bcc_ptr;
740 }
741 
unicode_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)742 static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
743 				   const struct nls_table *nls_cp)
744 {
745 	char *bcc_ptr = *pbcc_area;
746 	int bytes_ret = 0;
747 
748 	/* BB FIXME add check that strings less than 335 or will need to send as arrays */
749 
750 	/* copy user */
751 	if (ses->user_name == NULL) {
752 		/* null user mount */
753 		*bcc_ptr = 0;
754 		*(bcc_ptr+1) = 0;
755 	} else {
756 		bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
757 					    CIFS_MAX_USERNAME_LEN, nls_cp);
758 	}
759 	bcc_ptr += 2 * bytes_ret;
760 	bcc_ptr += 2; /* account for null termination */
761 
762 	unicode_domain_string(&bcc_ptr, ses, nls_cp);
763 	unicode_oslm_strings(&bcc_ptr, nls_cp);
764 
765 	*pbcc_area = bcc_ptr;
766 }
767 
ascii_ssetup_strings(char ** pbcc_area,struct cifs_ses * ses,const struct nls_table * nls_cp)768 static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
769 				 const struct nls_table *nls_cp)
770 {
771 	char *bcc_ptr = *pbcc_area;
772 	int len;
773 
774 	/* copy user */
775 	/* BB what about null user mounts - check that we do this BB */
776 	/* copy user */
777 	if (ses->user_name != NULL) {
778 		len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
779 		if (WARN_ON_ONCE(len < 0))
780 			len = CIFS_MAX_USERNAME_LEN - 1;
781 		bcc_ptr += len;
782 	}
783 	/* else null user mount */
784 	*bcc_ptr = 0;
785 	bcc_ptr++; /* account for null termination */
786 
787 	/* BB check for overflow here */
788 
789 	ascii_domain_string(&bcc_ptr, ses, nls_cp);
790 	ascii_oslm_strings(&bcc_ptr, nls_cp);
791 
792 	*pbcc_area = bcc_ptr;
793 }
794 
795 static void
decode_unicode_ssetup(char ** pbcc_area,int bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)796 decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
797 		      const struct nls_table *nls_cp)
798 {
799 	int len;
800 	char *data = *pbcc_area;
801 
802 	cifs_dbg(FYI, "bleft %d\n", bleft);
803 
804 	kfree(ses->serverOS);
805 	ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
806 	cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
807 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
808 	data += len;
809 	bleft -= len;
810 	if (bleft <= 0)
811 		return;
812 
813 	kfree(ses->serverNOS);
814 	ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
815 	cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
816 	len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
817 	data += len;
818 	bleft -= len;
819 	if (bleft <= 0)
820 		return;
821 
822 	kfree(ses->serverDomain);
823 	ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
824 	cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
825 
826 	return;
827 }
828 
decode_ascii_ssetup(char ** pbcc_area,__u16 bleft,struct cifs_ses * ses,const struct nls_table * nls_cp)829 static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
830 				struct cifs_ses *ses,
831 				const struct nls_table *nls_cp)
832 {
833 	int len;
834 	char *bcc_ptr = *pbcc_area;
835 
836 	cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
837 
838 	len = strnlen(bcc_ptr, bleft);
839 	if (len >= bleft)
840 		return;
841 
842 	kfree(ses->serverOS);
843 
844 	ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
845 	if (ses->serverOS) {
846 		memcpy(ses->serverOS, bcc_ptr, len);
847 		ses->serverOS[len] = 0;
848 		if (strncmp(ses->serverOS, "OS/2", 4) == 0)
849 			cifs_dbg(FYI, "OS/2 server\n");
850 	}
851 
852 	bcc_ptr += len + 1;
853 	bleft -= len + 1;
854 
855 	len = strnlen(bcc_ptr, bleft);
856 	if (len >= bleft)
857 		return;
858 
859 	kfree(ses->serverNOS);
860 
861 	ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
862 	if (ses->serverNOS) {
863 		memcpy(ses->serverNOS, bcc_ptr, len);
864 		ses->serverNOS[len] = 0;
865 	}
866 
867 	bcc_ptr += len + 1;
868 	bleft -= len + 1;
869 
870 	len = strnlen(bcc_ptr, bleft);
871 	if (len > bleft)
872 		return;
873 
874 	/*
875 	 * No domain field in LANMAN case. Domain is
876 	 * returned by old servers in the SMB negprot response
877 	 *
878 	 * BB For newer servers which do not support Unicode,
879 	 * but thus do return domain here, we could add parsing
880 	 * for it later, but it is not very important
881 	 */
882 	cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
883 }
884 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
885 
decode_ntlmssp_challenge(char * bcc_ptr,int blob_len,struct cifs_ses * ses)886 int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
887 				    struct cifs_ses *ses)
888 {
889 	unsigned int tioffset; /* challenge message target info area */
890 	unsigned int tilen; /* challenge message target info area length  */
891 	CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
892 	__u32 server_flags;
893 
894 	if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
895 		cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
896 		return -EINVAL;
897 	}
898 
899 	if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
900 		cifs_dbg(VFS, "blob signature incorrect %s\n",
901 			 pblob->Signature);
902 		return -EINVAL;
903 	}
904 	if (pblob->MessageType != NtLmChallenge) {
905 		cifs_dbg(VFS, "Incorrect message type %d\n",
906 			 pblob->MessageType);
907 		return -EINVAL;
908 	}
909 
910 	server_flags = le32_to_cpu(pblob->NegotiateFlags);
911 	cifs_dbg(FYI, "%s: negotiate=0x%08x challenge=0x%08x\n", __func__,
912 		 ses->ntlmssp->client_flags, server_flags);
913 
914 	if ((ses->ntlmssp->client_flags & (NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_SIGN)) &&
915 	    (!(server_flags & NTLMSSP_NEGOTIATE_56) && !(server_flags & NTLMSSP_NEGOTIATE_128))) {
916 		cifs_dbg(VFS, "%s: requested signing/encryption but server did not return either 56-bit or 128-bit session key size\n",
917 			 __func__);
918 		return -EINVAL;
919 	}
920 	if (!(server_flags & NTLMSSP_NEGOTIATE_NTLM) && !(server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC)) {
921 		cifs_dbg(VFS, "%s: server does not seem to support either NTLMv1 or NTLMv2\n", __func__);
922 		return -EINVAL;
923 	}
924 	if (ses->server->sign && !(server_flags & NTLMSSP_NEGOTIATE_SIGN)) {
925 		cifs_dbg(VFS, "%s: forced packet signing but server does not seem to support it\n",
926 			 __func__);
927 		return -EOPNOTSUPP;
928 	}
929 	if ((ses->ntlmssp->client_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
930 	    !(server_flags & NTLMSSP_NEGOTIATE_KEY_XCH))
931 		pr_warn_once("%s: authentication has been weakened as server does not support key exchange\n",
932 			     __func__);
933 
934 	ses->ntlmssp->server_flags = server_flags;
935 
936 	memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
937 	/*
938 	 * In particular we can examine sign flags
939 	 *
940 	 * BB spec says that if AvId field of MsvAvTimestamp is populated then
941 	 * we must set the MIC field of the AUTHENTICATE_MESSAGE
942 	 */
943 
944 	tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
945 	tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
946 	if (tioffset > blob_len || tioffset + tilen > blob_len) {
947 		cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
948 			 tioffset, tilen);
949 		return -EINVAL;
950 	}
951 	if (tilen) {
952 		kfree_sensitive(ses->auth_key.response);
953 		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
954 						 GFP_KERNEL);
955 		if (!ses->auth_key.response) {
956 			cifs_dbg(VFS, "Challenge target info alloc failure\n");
957 			return -ENOMEM;
958 		}
959 		ses->auth_key.len = tilen;
960 	}
961 
962 	return 0;
963 }
964 
size_of_ntlmssp_blob(struct cifs_ses * ses,int base_size)965 static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
966 {
967 	int sz = base_size + ses->auth_key.len
968 		- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
969 
970 	if (ses->domainName)
971 		sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
972 	else
973 		sz += sizeof(__le16);
974 
975 	if (ses->user_name)
976 		sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
977 	else
978 		sz += sizeof(__le16);
979 
980 	if (ses->workstation_name[0])
981 		sz += sizeof(__le16) * strnlen(ses->workstation_name,
982 					       ntlmssp_workstation_name_size(ses));
983 	else
984 		sz += sizeof(__le16);
985 
986 	return sz;
987 }
988 
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)989 static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
990 						 char *str_value,
991 						 int str_length,
992 						 unsigned char *pstart,
993 						 unsigned char **pcur,
994 						 const struct nls_table *nls_cp)
995 {
996 	unsigned char *tmp = pstart;
997 	int len;
998 
999 	if (!pbuf)
1000 		return;
1001 
1002 	if (!pcur)
1003 		pcur = &tmp;
1004 
1005 	if (!str_value) {
1006 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1007 		pbuf->Length = 0;
1008 		pbuf->MaximumLength = 0;
1009 		*pcur += sizeof(__le16);
1010 	} else {
1011 		len = cifs_strtoUTF16((__le16 *)*pcur,
1012 				      str_value,
1013 				      str_length,
1014 				      nls_cp);
1015 		len *= sizeof(__le16);
1016 		pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
1017 		pbuf->Length = cpu_to_le16(len);
1018 		pbuf->MaximumLength = cpu_to_le16(len);
1019 		*pcur += len;
1020 	}
1021 }
1022 
1023 /* BB Move to ntlmssp.c eventually */
1024 
build_ntlmssp_negotiate_blob(unsigned char ** pbuffer,u16 * buflen,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1025 int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
1026 				 u16 *buflen,
1027 				 struct cifs_ses *ses,
1028 				 struct TCP_Server_Info *server,
1029 				 const struct nls_table *nls_cp)
1030 {
1031 	int rc = 0;
1032 	NEGOTIATE_MESSAGE *sec_blob;
1033 	__u32 flags;
1034 	unsigned char *tmp;
1035 	int len;
1036 
1037 	len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
1038 	*pbuffer = kmalloc(len, GFP_KERNEL);
1039 	if (!*pbuffer) {
1040 		rc = -ENOMEM;
1041 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1042 		*buflen = 0;
1043 		goto setup_ntlm_neg_ret;
1044 	}
1045 	sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
1046 
1047 	memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
1048 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1049 	sec_blob->MessageType = NtLmNegotiate;
1050 
1051 	/* BB is NTLMV2 session security format easier to use here? */
1052 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1053 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1054 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1055 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1056 		NTLMSSP_NEGOTIATE_SIGN;
1057 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1058 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1059 
1060 	tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
1061 	ses->ntlmssp->client_flags = flags;
1062 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1063 
1064 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1065 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1066 				      NULL,
1067 				      CIFS_MAX_DOMAINNAME_LEN,
1068 				      *pbuffer, &tmp,
1069 				      nls_cp);
1070 
1071 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1072 				      NULL,
1073 				      CIFS_MAX_WORKSTATION_LEN,
1074 				      *pbuffer, &tmp,
1075 				      nls_cp);
1076 
1077 	*buflen = tmp - *pbuffer;
1078 setup_ntlm_neg_ret:
1079 	return rc;
1080 }
1081 
1082 /*
1083  * Build ntlmssp blob with additional fields, such as version,
1084  * supported by modern servers. For safety limit to SMB3 or later
1085  * See notes in MS-NLMP Section 2.2.2.1 e.g.
1086  */
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)1087 int build_ntlmssp_smb3_negotiate_blob(unsigned char **pbuffer,
1088 				 u16 *buflen,
1089 				 struct cifs_ses *ses,
1090 				 struct TCP_Server_Info *server,
1091 				 const struct nls_table *nls_cp)
1092 {
1093 	int rc = 0;
1094 	struct negotiate_message *sec_blob;
1095 	__u32 flags;
1096 	unsigned char *tmp;
1097 	int len;
1098 
1099 	len = size_of_ntlmssp_blob(ses, sizeof(struct negotiate_message));
1100 	*pbuffer = kmalloc(len, GFP_KERNEL);
1101 	if (!*pbuffer) {
1102 		rc = -ENOMEM;
1103 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1104 		*buflen = 0;
1105 		goto setup_ntlm_smb3_neg_ret;
1106 	}
1107 	sec_blob = (struct negotiate_message *)*pbuffer;
1108 
1109 	memset(*pbuffer, 0, sizeof(struct negotiate_message));
1110 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1111 	sec_blob->MessageType = NtLmNegotiate;
1112 
1113 	/* BB is NTLMV2 session security format easier to use here? */
1114 	flags = NTLMSSP_NEGOTIATE_56 |	NTLMSSP_REQUEST_TARGET |
1115 		NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
1116 		NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
1117 		NTLMSSP_NEGOTIATE_ALWAYS_SIGN | NTLMSSP_NEGOTIATE_SEAL |
1118 		NTLMSSP_NEGOTIATE_SIGN | NTLMSSP_NEGOTIATE_VERSION;
1119 	if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
1120 		flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
1121 
1122 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1123 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1124 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1125 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1126 
1127 	tmp = *pbuffer + sizeof(struct negotiate_message);
1128 	ses->ntlmssp->client_flags = flags;
1129 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1130 
1131 	/* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
1132 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1133 				      NULL,
1134 				      CIFS_MAX_DOMAINNAME_LEN,
1135 				      *pbuffer, &tmp,
1136 				      nls_cp);
1137 
1138 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1139 				      NULL,
1140 				      CIFS_MAX_WORKSTATION_LEN,
1141 				      *pbuffer, &tmp,
1142 				      nls_cp);
1143 
1144 	*buflen = tmp - *pbuffer;
1145 setup_ntlm_smb3_neg_ret:
1146 	return rc;
1147 }
1148 
1149 
1150 /* 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)1151 int build_ntlmssp_auth_blob(unsigned char **pbuffer,
1152 					u16 *buflen,
1153 				   struct cifs_ses *ses,
1154 				   struct TCP_Server_Info *server,
1155 				   const struct nls_table *nls_cp)
1156 {
1157 	int rc;
1158 	AUTHENTICATE_MESSAGE *sec_blob;
1159 	__u32 flags;
1160 	unsigned char *tmp;
1161 	int len;
1162 
1163 	rc = setup_ntlmv2_rsp(ses, nls_cp);
1164 	if (rc) {
1165 		cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
1166 		*buflen = 0;
1167 		goto setup_ntlmv2_ret;
1168 	}
1169 
1170 	len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
1171 	*pbuffer = kmalloc(len, GFP_KERNEL);
1172 	if (!*pbuffer) {
1173 		rc = -ENOMEM;
1174 		cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
1175 		*buflen = 0;
1176 		goto setup_ntlmv2_ret;
1177 	}
1178 	sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
1179 
1180 	memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
1181 	sec_blob->MessageType = NtLmAuthenticate;
1182 
1183 	/* send version information in ntlmssp authenticate also */
1184 	flags = ses->ntlmssp->server_flags | NTLMSSP_REQUEST_TARGET |
1185 		NTLMSSP_NEGOTIATE_TARGET_INFO | NTLMSSP_NEGOTIATE_VERSION |
1186 		NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
1187 
1188 	sec_blob->Version.ProductMajorVersion = LINUX_VERSION_MAJOR;
1189 	sec_blob->Version.ProductMinorVersion = LINUX_VERSION_PATCHLEVEL;
1190 	sec_blob->Version.ProductBuild = cpu_to_le16(SMB3_PRODUCT_BUILD);
1191 	sec_blob->Version.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
1192 
1193 	tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
1194 	sec_blob->NegotiateFlags = cpu_to_le32(flags);
1195 
1196 	sec_blob->LmChallengeResponse.BufferOffset =
1197 				cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
1198 	sec_blob->LmChallengeResponse.Length = 0;
1199 	sec_blob->LmChallengeResponse.MaximumLength = 0;
1200 
1201 	sec_blob->NtChallengeResponse.BufferOffset =
1202 				cpu_to_le32(tmp - *pbuffer);
1203 	if (ses->user_name != NULL) {
1204 		memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1205 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1206 		tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1207 
1208 		sec_blob->NtChallengeResponse.Length =
1209 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1210 		sec_blob->NtChallengeResponse.MaximumLength =
1211 				cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1212 	} else {
1213 		/*
1214 		 * don't send an NT Response for anonymous access
1215 		 */
1216 		sec_blob->NtChallengeResponse.Length = 0;
1217 		sec_blob->NtChallengeResponse.MaximumLength = 0;
1218 	}
1219 
1220 	cifs_security_buffer_from_str(&sec_blob->DomainName,
1221 				      ses->domainName,
1222 				      CIFS_MAX_DOMAINNAME_LEN,
1223 				      *pbuffer, &tmp,
1224 				      nls_cp);
1225 
1226 	cifs_security_buffer_from_str(&sec_blob->UserName,
1227 				      ses->user_name,
1228 				      CIFS_MAX_USERNAME_LEN,
1229 				      *pbuffer, &tmp,
1230 				      nls_cp);
1231 
1232 	cifs_security_buffer_from_str(&sec_blob->WorkstationName,
1233 				      ses->workstation_name,
1234 				      ntlmssp_workstation_name_size(ses),
1235 				      *pbuffer, &tmp,
1236 				      nls_cp);
1237 
1238 	if ((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) &&
1239 	    (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess) &&
1240 	    !calc_seckey(ses)) {
1241 		memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
1242 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1243 		sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
1244 		sec_blob->SessionKey.MaximumLength =
1245 				cpu_to_le16(CIFS_CPHTXT_SIZE);
1246 		tmp += CIFS_CPHTXT_SIZE;
1247 	} else {
1248 		sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
1249 		sec_blob->SessionKey.Length = 0;
1250 		sec_blob->SessionKey.MaximumLength = 0;
1251 	}
1252 
1253 	*buflen = tmp - *pbuffer;
1254 setup_ntlmv2_ret:
1255 	return rc;
1256 }
1257 
1258 enum securityEnum
cifs_select_sectype(struct TCP_Server_Info * server,enum securityEnum requested)1259 cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
1260 {
1261 	switch (server->negflavor) {
1262 	case CIFS_NEGFLAVOR_EXTENDED:
1263 		switch (requested) {
1264 		case Kerberos:
1265 		case RawNTLMSSP:
1266 		case IAKerb:
1267 			return requested;
1268 		case Unspecified:
1269 			if (server->sec_ntlmssp &&
1270 			    (global_secflags & CIFSSEC_MAY_NTLMSSP))
1271 				return RawNTLMSSP;
1272 			if ((server->sec_kerberos || server->sec_mskerberos || server->sec_iakerb) &&
1273 			    (global_secflags & CIFSSEC_MAY_KRB5))
1274 				return Kerberos;
1275 			fallthrough;
1276 		default:
1277 			return Unspecified;
1278 		}
1279 	case CIFS_NEGFLAVOR_UNENCAP:
1280 		switch (requested) {
1281 		case NTLMv2:
1282 			return requested;
1283 		case Unspecified:
1284 			if (global_secflags & CIFSSEC_MAY_NTLMV2)
1285 				return NTLMv2;
1286 			break;
1287 		default:
1288 			break;
1289 		}
1290 		fallthrough;
1291 	default:
1292 		return Unspecified;
1293 	}
1294 }
1295 
1296 struct sess_data {
1297 	unsigned int xid;
1298 	struct cifs_ses *ses;
1299 	struct TCP_Server_Info *server;
1300 	struct nls_table *nls_cp;
1301 	void (*func)(struct sess_data *);
1302 	int result;
1303 
1304 	/* we will send the SMB in three pieces:
1305 	 * a fixed length beginning part, an optional
1306 	 * SPNEGO blob (which can be zero length), and a
1307 	 * last part which will include the strings
1308 	 * and rest of bcc area. This allows us to avoid
1309 	 * a large buffer 17K allocation
1310 	 */
1311 	int buf0_type;
1312 	struct kvec iov[3];
1313 };
1314 
1315 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1316 static int
sess_alloc_buffer(struct sess_data * sess_data,int wct)1317 sess_alloc_buffer(struct sess_data *sess_data, int wct)
1318 {
1319 	int rc;
1320 	struct cifs_ses *ses = sess_data->ses;
1321 	struct smb_hdr *smb_buf;
1322 
1323 	rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
1324 				  (void **)&smb_buf);
1325 
1326 	if (rc)
1327 		return rc;
1328 
1329 	sess_data->iov[0].iov_base = (char *)smb_buf;
1330 	sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
1331 	/*
1332 	 * This variable will be used to clear the buffer
1333 	 * allocated above in case of any error in the calling function.
1334 	 */
1335 	sess_data->buf0_type = CIFS_SMALL_BUFFER;
1336 
1337 	/* 2000 big enough to fit max user, domain, NOS name etc. */
1338 	sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
1339 	if (!sess_data->iov[2].iov_base) {
1340 		rc = -ENOMEM;
1341 		goto out_free_smb_buf;
1342 	}
1343 
1344 	return 0;
1345 
1346 out_free_smb_buf:
1347 	cifs_small_buf_release(smb_buf);
1348 	sess_data->iov[0].iov_base = NULL;
1349 	sess_data->iov[0].iov_len = 0;
1350 	sess_data->buf0_type = CIFS_NO_BUFFER;
1351 	return rc;
1352 }
1353 
1354 static void
sess_free_buffer(struct sess_data * sess_data)1355 sess_free_buffer(struct sess_data *sess_data)
1356 {
1357 	struct kvec *iov = sess_data->iov;
1358 
1359 	/*
1360 	 * Zero the session data before freeing, as it might contain sensitive info (keys, etc).
1361 	 * Note that iov[1] is already freed by caller.
1362 	 */
1363 	if (sess_data->buf0_type != CIFS_NO_BUFFER && iov[0].iov_base)
1364 		memzero_explicit(iov[0].iov_base, iov[0].iov_len);
1365 
1366 	free_rsp_buf(sess_data->buf0_type, iov[0].iov_base);
1367 	sess_data->buf0_type = CIFS_NO_BUFFER;
1368 	kfree_sensitive(iov[2].iov_base);
1369 }
1370 
1371 static int
sess_establish_session(struct sess_data * sess_data)1372 sess_establish_session(struct sess_data *sess_data)
1373 {
1374 	struct cifs_ses *ses = sess_data->ses;
1375 	struct TCP_Server_Info *server = sess_data->server;
1376 
1377 	cifs_server_lock(server);
1378 	if (!server->session_estab) {
1379 		if (server->sign) {
1380 			server->session_key.response =
1381 				kmemdup(ses->auth_key.response,
1382 				ses->auth_key.len, GFP_KERNEL);
1383 			if (!server->session_key.response) {
1384 				cifs_server_unlock(server);
1385 				return -ENOMEM;
1386 			}
1387 			server->session_key.len =
1388 						ses->auth_key.len;
1389 		}
1390 		server->sequence_number = 0x2;
1391 		server->session_estab = true;
1392 	}
1393 	cifs_server_unlock(server);
1394 
1395 	cifs_dbg(FYI, "CIFS session established successfully\n");
1396 	return 0;
1397 }
1398 
1399 static int
sess_sendreceive(struct sess_data * sess_data)1400 sess_sendreceive(struct sess_data *sess_data)
1401 {
1402 	int rc;
1403 	struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
1404 	__u16 count;
1405 	struct kvec rsp_iov = { NULL, 0 };
1406 
1407 	count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
1408 	be32_add_cpu(&smb_buf->smb_buf_length, count);
1409 	put_bcc(count, smb_buf);
1410 
1411 	rc = SendReceive2(sess_data->xid, sess_data->ses,
1412 			  sess_data->iov, 3 /* num_iovecs */,
1413 			  &sess_data->buf0_type,
1414 			  CIFS_LOG_ERROR, &rsp_iov);
1415 	cifs_small_buf_release(sess_data->iov[0].iov_base);
1416 	memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
1417 
1418 	return rc;
1419 }
1420 
1421 static void
sess_auth_ntlmv2(struct sess_data * sess_data)1422 sess_auth_ntlmv2(struct sess_data *sess_data)
1423 {
1424 	int rc = 0;
1425 	struct smb_hdr *smb_buf;
1426 	SESSION_SETUP_ANDX *pSMB;
1427 	char *bcc_ptr;
1428 	struct cifs_ses *ses = sess_data->ses;
1429 	struct TCP_Server_Info *server = sess_data->server;
1430 	__u32 capabilities;
1431 	__u16 bytes_remaining;
1432 
1433 	/* old style NTLM sessionsetup */
1434 	/* wct = 13 */
1435 	rc = sess_alloc_buffer(sess_data, 13);
1436 	if (rc)
1437 		goto out;
1438 
1439 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1440 	bcc_ptr = sess_data->iov[2].iov_base;
1441 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1442 
1443 	pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
1444 
1445 	/* LM2 password would be here if we supported it */
1446 	pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
1447 
1448 	if (ses->user_name != NULL) {
1449 		/* calculate nlmv2 response and session key */
1450 		rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
1451 		if (rc) {
1452 			cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
1453 			goto out;
1454 		}
1455 
1456 		memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
1457 				ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1458 		bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
1459 
1460 		/* set case sensitive password length after tilen may get
1461 		 * assigned, tilen is 0 otherwise.
1462 		 */
1463 		pSMB->req_no_secext.CaseSensitivePasswordLength =
1464 			cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
1465 	} else {
1466 		pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
1467 	}
1468 
1469 	if (ses->capabilities & CAP_UNICODE) {
1470 		if (!IS_ALIGNED(sess_data->iov[0].iov_len, 2)) {
1471 			*bcc_ptr = 0;
1472 			bcc_ptr++;
1473 		}
1474 		unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1475 	} else {
1476 		ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
1477 	}
1478 
1479 
1480 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1481 			(long) sess_data->iov[2].iov_base;
1482 
1483 	rc = sess_sendreceive(sess_data);
1484 	if (rc)
1485 		goto out;
1486 
1487 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1488 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1489 
1490 	if (smb_buf->WordCount != 3) {
1491 		rc = -EIO;
1492 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1493 		goto out;
1494 	}
1495 
1496 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1497 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1498 
1499 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1500 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1501 
1502 	bytes_remaining = get_bcc(smb_buf);
1503 	bcc_ptr = pByteArea(smb_buf);
1504 
1505 	/* BB check if Unicode and decode strings */
1506 	if (bytes_remaining == 0) {
1507 		/* no string area to decode, do nothing */
1508 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1509 		/* unicode string area must be word-aligned */
1510 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1511 			++bcc_ptr;
1512 			--bytes_remaining;
1513 		}
1514 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1515 				      sess_data->nls_cp);
1516 	} else {
1517 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1518 				    sess_data->nls_cp);
1519 	}
1520 
1521 	rc = sess_establish_session(sess_data);
1522 out:
1523 	sess_data->result = rc;
1524 	sess_data->func = NULL;
1525 	sess_free_buffer(sess_data);
1526 	kfree_sensitive(ses->auth_key.response);
1527 	ses->auth_key.response = NULL;
1528 }
1529 
1530 #ifdef CONFIG_CIFS_UPCALL
1531 static void
sess_auth_kerberos(struct sess_data * sess_data)1532 sess_auth_kerberos(struct sess_data *sess_data)
1533 {
1534 	int rc = 0;
1535 	struct smb_hdr *smb_buf;
1536 	SESSION_SETUP_ANDX *pSMB;
1537 	char *bcc_ptr;
1538 	struct cifs_ses *ses = sess_data->ses;
1539 	struct TCP_Server_Info *server = sess_data->server;
1540 	__u32 capabilities;
1541 	__u16 bytes_remaining;
1542 	struct key *spnego_key = NULL;
1543 	struct cifs_spnego_msg *msg;
1544 	u16 blob_len;
1545 
1546 	/* extended security */
1547 	/* wct = 12 */
1548 	rc = sess_alloc_buffer(sess_data, 12);
1549 	if (rc)
1550 		goto out;
1551 
1552 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1553 	bcc_ptr = sess_data->iov[2].iov_base;
1554 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1555 
1556 	spnego_key = cifs_get_spnego_key(ses, server);
1557 	if (IS_ERR(spnego_key)) {
1558 		rc = PTR_ERR(spnego_key);
1559 		spnego_key = NULL;
1560 		goto out;
1561 	}
1562 
1563 	msg = spnego_key->payload.data[0];
1564 	/*
1565 	 * check version field to make sure that cifs.upcall is
1566 	 * sending us a response in an expected form
1567 	 */
1568 	if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
1569 		cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
1570 			 CIFS_SPNEGO_UPCALL_VERSION, msg->version);
1571 		rc = -EKEYREJECTED;
1572 		goto out_put_spnego_key;
1573 	}
1574 
1575 	kfree_sensitive(ses->auth_key.response);
1576 	ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
1577 					 GFP_KERNEL);
1578 	if (!ses->auth_key.response) {
1579 		cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
1580 			 msg->sesskey_len);
1581 		rc = -ENOMEM;
1582 		goto out_put_spnego_key;
1583 	}
1584 	ses->auth_key.len = msg->sesskey_len;
1585 
1586 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1587 	capabilities |= CAP_EXTENDED_SECURITY;
1588 	pSMB->req.Capabilities = cpu_to_le32(capabilities);
1589 	sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
1590 	sess_data->iov[1].iov_len = msg->secblob_len;
1591 	pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
1592 
1593 	if (pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) {
1594 		/* unicode strings must be word aligned */
1595 		if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1596 			*bcc_ptr = 0;
1597 			bcc_ptr++;
1598 		}
1599 		unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1600 		unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1601 	} else {
1602 		ascii_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1603 		ascii_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
1604 	}
1605 
1606 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1607 			(long) sess_data->iov[2].iov_base;
1608 
1609 	rc = sess_sendreceive(sess_data);
1610 	if (rc)
1611 		goto out_put_spnego_key;
1612 
1613 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1614 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1615 
1616 	if (smb_buf->WordCount != 4) {
1617 		rc = -EIO;
1618 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1619 		goto out_put_spnego_key;
1620 	}
1621 
1622 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1623 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1624 
1625 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1626 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1627 
1628 	bytes_remaining = get_bcc(smb_buf);
1629 	bcc_ptr = pByteArea(smb_buf);
1630 
1631 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1632 	if (blob_len > bytes_remaining) {
1633 		cifs_dbg(VFS, "bad security blob length %d\n",
1634 				blob_len);
1635 		rc = -EINVAL;
1636 		goto out_put_spnego_key;
1637 	}
1638 	bcc_ptr += blob_len;
1639 	bytes_remaining -= blob_len;
1640 
1641 	/* BB check if Unicode and decode strings */
1642 	if (bytes_remaining == 0) {
1643 		/* no string area to decode, do nothing */
1644 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1645 		/* unicode string area must be word-aligned */
1646 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1647 			++bcc_ptr;
1648 			--bytes_remaining;
1649 		}
1650 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1651 				      sess_data->nls_cp);
1652 	} else {
1653 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1654 				    sess_data->nls_cp);
1655 	}
1656 
1657 	rc = sess_establish_session(sess_data);
1658 out_put_spnego_key:
1659 	key_invalidate(spnego_key);
1660 	key_put(spnego_key);
1661 out:
1662 	sess_data->result = rc;
1663 	sess_data->func = NULL;
1664 	sess_free_buffer(sess_data);
1665 	kfree_sensitive(ses->auth_key.response);
1666 	ses->auth_key.response = NULL;
1667 }
1668 
1669 #endif /* ! CONFIG_CIFS_UPCALL */
1670 
1671 /*
1672  * The required kvec buffers have to be allocated before calling this
1673  * function.
1674  */
1675 static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data * sess_data)1676 _sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
1677 {
1678 	SESSION_SETUP_ANDX *pSMB;
1679 	struct cifs_ses *ses = sess_data->ses;
1680 	struct TCP_Server_Info *server = sess_data->server;
1681 	__u32 capabilities;
1682 	char *bcc_ptr;
1683 
1684 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1685 
1686 	capabilities = cifs_ssetup_hdr(ses, server, pSMB);
1687 	if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
1688 		cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
1689 		return -ENOSYS;
1690 	}
1691 
1692 	pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
1693 	capabilities |= CAP_EXTENDED_SECURITY;
1694 	pSMB->req.Capabilities |= cpu_to_le32(capabilities);
1695 
1696 	bcc_ptr = sess_data->iov[2].iov_base;
1697 	/* unicode strings must be word aligned */
1698 	if (!IS_ALIGNED(sess_data->iov[0].iov_len + sess_data->iov[1].iov_len, 2)) {
1699 		*bcc_ptr = 0;
1700 		bcc_ptr++;
1701 	}
1702 	unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
1703 
1704 	sess_data->iov[2].iov_len = (long) bcc_ptr -
1705 					(long) sess_data->iov[2].iov_base;
1706 
1707 	return 0;
1708 }
1709 
1710 static void
1711 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
1712 
1713 static void
sess_auth_rawntlmssp_negotiate(struct sess_data * sess_data)1714 sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
1715 {
1716 	int rc;
1717 	struct smb_hdr *smb_buf;
1718 	SESSION_SETUP_ANDX *pSMB;
1719 	struct cifs_ses *ses = sess_data->ses;
1720 	struct TCP_Server_Info *server = sess_data->server;
1721 	__u16 bytes_remaining;
1722 	char *bcc_ptr;
1723 	unsigned char *ntlmsspblob = NULL;
1724 	u16 blob_len;
1725 
1726 	cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
1727 
1728 	/*
1729 	 * if memory allocation is successful, caller of this function
1730 	 * frees it.
1731 	 */
1732 	ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
1733 	if (!ses->ntlmssp) {
1734 		rc = -ENOMEM;
1735 		goto out;
1736 	}
1737 	ses->ntlmssp->sesskey_per_smbsess = false;
1738 
1739 	/* wct = 12 */
1740 	rc = sess_alloc_buffer(sess_data, 12);
1741 	if (rc)
1742 		goto out;
1743 
1744 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1745 
1746 	/* Build security blob before we assemble the request */
1747 	rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
1748 				     &blob_len, ses, server,
1749 				     sess_data->nls_cp);
1750 	if (rc)
1751 		goto out_free_ntlmsspblob;
1752 
1753 	sess_data->iov[1].iov_len = blob_len;
1754 	sess_data->iov[1].iov_base = ntlmsspblob;
1755 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1756 
1757 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1758 	if (rc)
1759 		goto out_free_ntlmsspblob;
1760 
1761 	rc = sess_sendreceive(sess_data);
1762 
1763 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1764 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1765 
1766 	/* If true, rc here is expected and not an error */
1767 	if (sess_data->buf0_type != CIFS_NO_BUFFER &&
1768 	    smb_buf->Status.CifsError ==
1769 			cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
1770 		rc = 0;
1771 
1772 	if (rc)
1773 		goto out_free_ntlmsspblob;
1774 
1775 	cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
1776 
1777 	if (smb_buf->WordCount != 4) {
1778 		rc = -EIO;
1779 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1780 		goto out_free_ntlmsspblob;
1781 	}
1782 
1783 	ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
1784 	cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
1785 
1786 	bytes_remaining = get_bcc(smb_buf);
1787 	bcc_ptr = pByteArea(smb_buf);
1788 
1789 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1790 	if (blob_len > bytes_remaining) {
1791 		cifs_dbg(VFS, "bad security blob length %d\n",
1792 				blob_len);
1793 		rc = -EINVAL;
1794 		goto out_free_ntlmsspblob;
1795 	}
1796 
1797 	rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
1798 
1799 out_free_ntlmsspblob:
1800 	kfree_sensitive(ntlmsspblob);
1801 out:
1802 	sess_free_buffer(sess_data);
1803 
1804 	if (!rc) {
1805 		sess_data->func = sess_auth_rawntlmssp_authenticate;
1806 		return;
1807 	}
1808 
1809 	/* Else error. Cleanup */
1810 	kfree_sensitive(ses->auth_key.response);
1811 	ses->auth_key.response = NULL;
1812 	kfree_sensitive(ses->ntlmssp);
1813 	ses->ntlmssp = NULL;
1814 
1815 	sess_data->func = NULL;
1816 	sess_data->result = rc;
1817 }
1818 
1819 static void
sess_auth_rawntlmssp_authenticate(struct sess_data * sess_data)1820 sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
1821 {
1822 	int rc;
1823 	struct smb_hdr *smb_buf;
1824 	SESSION_SETUP_ANDX *pSMB;
1825 	struct cifs_ses *ses = sess_data->ses;
1826 	struct TCP_Server_Info *server = sess_data->server;
1827 	__u16 bytes_remaining;
1828 	char *bcc_ptr;
1829 	unsigned char *ntlmsspblob = NULL;
1830 	u16 blob_len;
1831 
1832 	cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
1833 
1834 	/* wct = 12 */
1835 	rc = sess_alloc_buffer(sess_data, 12);
1836 	if (rc)
1837 		goto out;
1838 
1839 	/* Build security blob before we assemble the request */
1840 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1841 	smb_buf = (struct smb_hdr *)pSMB;
1842 	rc = build_ntlmssp_auth_blob(&ntlmsspblob,
1843 					&blob_len, ses, server,
1844 					sess_data->nls_cp);
1845 	if (rc)
1846 		goto out_free_ntlmsspblob;
1847 	sess_data->iov[1].iov_len = blob_len;
1848 	sess_data->iov[1].iov_base = ntlmsspblob;
1849 	pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
1850 	/*
1851 	 * Make sure that we tell the server that we are using
1852 	 * the uid that it just gave us back on the response
1853 	 * (challenge)
1854 	 */
1855 	smb_buf->Uid = ses->Suid;
1856 
1857 	rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
1858 	if (rc)
1859 		goto out_free_ntlmsspblob;
1860 
1861 	rc = sess_sendreceive(sess_data);
1862 	if (rc)
1863 		goto out_free_ntlmsspblob;
1864 
1865 	pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
1866 	smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
1867 	if (smb_buf->WordCount != 4) {
1868 		rc = -EIO;
1869 		cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
1870 		goto out_free_ntlmsspblob;
1871 	}
1872 
1873 	if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
1874 		cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
1875 
1876 	if (ses->Suid != smb_buf->Uid) {
1877 		ses->Suid = smb_buf->Uid;
1878 		cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
1879 	}
1880 
1881 	bytes_remaining = get_bcc(smb_buf);
1882 	bcc_ptr = pByteArea(smb_buf);
1883 	blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
1884 	if (blob_len > bytes_remaining) {
1885 		cifs_dbg(VFS, "bad security blob length %d\n",
1886 				blob_len);
1887 		rc = -EINVAL;
1888 		goto out_free_ntlmsspblob;
1889 	}
1890 	bcc_ptr += blob_len;
1891 	bytes_remaining -= blob_len;
1892 
1893 
1894 	/* BB check if Unicode and decode strings */
1895 	if (bytes_remaining == 0) {
1896 		/* no string area to decode, do nothing */
1897 	} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
1898 		/* unicode string area must be word-aligned */
1899 		if (!IS_ALIGNED((unsigned long)bcc_ptr - (unsigned long)smb_buf, 2)) {
1900 			++bcc_ptr;
1901 			--bytes_remaining;
1902 		}
1903 		decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
1904 				      sess_data->nls_cp);
1905 	} else {
1906 		decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
1907 				    sess_data->nls_cp);
1908 	}
1909 
1910 out_free_ntlmsspblob:
1911 	kfree_sensitive(ntlmsspblob);
1912 out:
1913 	sess_free_buffer(sess_data);
1914 
1915 	if (!rc)
1916 		rc = sess_establish_session(sess_data);
1917 
1918 	/* Cleanup */
1919 	kfree_sensitive(ses->auth_key.response);
1920 	ses->auth_key.response = NULL;
1921 	kfree_sensitive(ses->ntlmssp);
1922 	ses->ntlmssp = NULL;
1923 
1924 	sess_data->func = NULL;
1925 	sess_data->result = rc;
1926 }
1927 
select_sec(struct sess_data * sess_data)1928 static int select_sec(struct sess_data *sess_data)
1929 {
1930 	int type;
1931 	struct cifs_ses *ses = sess_data->ses;
1932 	struct TCP_Server_Info *server = sess_data->server;
1933 
1934 	type = cifs_select_sectype(server, ses->sectype);
1935 	cifs_dbg(FYI, "sess setup type %d\n", type);
1936 	if (type == Unspecified) {
1937 		cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
1938 		return -EINVAL;
1939 	}
1940 
1941 	switch (type) {
1942 	case NTLMv2:
1943 		sess_data->func = sess_auth_ntlmv2;
1944 		break;
1945 	case Kerberos:
1946 #ifdef CONFIG_CIFS_UPCALL
1947 		sess_data->func = sess_auth_kerberos;
1948 		break;
1949 #else
1950 		cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
1951 		return -ENOSYS;
1952 #endif /* CONFIG_CIFS_UPCALL */
1953 	case RawNTLMSSP:
1954 		sess_data->func = sess_auth_rawntlmssp_negotiate;
1955 		break;
1956 	default:
1957 		cifs_dbg(VFS, "secType %d not supported!\n", type);
1958 		return -ENOSYS;
1959 	}
1960 
1961 	return 0;
1962 }
1963 
CIFS_SessSetup(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server,const struct nls_table * nls_cp)1964 int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
1965 		   struct TCP_Server_Info *server,
1966 		   const struct nls_table *nls_cp)
1967 {
1968 	int rc = 0;
1969 	struct sess_data *sess_data;
1970 
1971 	if (ses == NULL) {
1972 		WARN(1, "%s: ses == NULL!", __func__);
1973 		return -EINVAL;
1974 	}
1975 
1976 	sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
1977 	if (!sess_data)
1978 		return -ENOMEM;
1979 
1980 	sess_data->xid = xid;
1981 	sess_data->ses = ses;
1982 	sess_data->server = server;
1983 	sess_data->buf0_type = CIFS_NO_BUFFER;
1984 	sess_data->nls_cp = (struct nls_table *) nls_cp;
1985 
1986 	rc = select_sec(sess_data);
1987 	if (rc)
1988 		goto out;
1989 
1990 	while (sess_data->func)
1991 		sess_data->func(sess_data);
1992 
1993 	/* Store result before we free sess_data */
1994 	rc = sess_data->result;
1995 
1996 out:
1997 	kfree_sensitive(sess_data);
1998 	return rc;
1999 }
2000 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
2001