1 /*
2 * fs/cifs/smb2misc.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2011
5 * Etersoft, 2012
6 * Author(s): Steve French (sfrench@us.ibm.com)
7 * Pavel Shilovsky (pshilovsky@samba.org) 2012
8 *
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23 #include <linux/ctype.h>
24 #include "smb2pdu.h"
25 #include "cifsglob.h"
26 #include "cifsproto.h"
27 #include "smb2proto.h"
28 #include "cifs_debug.h"
29 #include "cifs_unicode.h"
30 #include "smb2status.h"
31 #include "smb2glob.h"
32 #include "nterr.h"
33
34 static int
check_smb2_hdr(struct smb2_sync_hdr * shdr,__u64 mid)35 check_smb2_hdr(struct smb2_sync_hdr *shdr, __u64 mid)
36 {
37 __u64 wire_mid = le64_to_cpu(shdr->MessageId);
38
39 /*
40 * Make sure that this really is an SMB, that it is a response,
41 * and that the message ids match.
42 */
43 if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
44 (mid == wire_mid)) {
45 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
46 return 0;
47 else {
48 /* only one valid case where server sends us request */
49 if (shdr->Command == SMB2_OPLOCK_BREAK)
50 return 0;
51 else
52 cifs_dbg(VFS, "Received Request not response\n");
53 }
54 } else { /* bad signature or mid */
55 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
56 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
57 le32_to_cpu(shdr->ProtocolId));
58 if (mid != wire_mid)
59 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
60 mid, wire_mid);
61 }
62 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
63 return 1;
64 }
65
66 /*
67 * The following table defines the expected "StructureSize" of SMB2 responses
68 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
69 *
70 * Note that commands are defined in smb2pdu.h in le16 but the array below is
71 * indexed by command in host byte order
72 */
73 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
74 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
75 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
76 /* SMB2_LOGOFF */ cpu_to_le16(4),
77 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
78 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
79 /* SMB2_CREATE */ cpu_to_le16(89),
80 /* SMB2_CLOSE */ cpu_to_le16(60),
81 /* SMB2_FLUSH */ cpu_to_le16(4),
82 /* SMB2_READ */ cpu_to_le16(17),
83 /* SMB2_WRITE */ cpu_to_le16(17),
84 /* SMB2_LOCK */ cpu_to_le16(4),
85 /* SMB2_IOCTL */ cpu_to_le16(49),
86 /* BB CHECK this ... not listed in documentation */
87 /* SMB2_CANCEL */ cpu_to_le16(0),
88 /* SMB2_ECHO */ cpu_to_le16(4),
89 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
90 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
91 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
92 /* SMB2_SET_INFO */ cpu_to_le16(2),
93 /* BB FIXME can also be 44 for lease break */
94 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
95 };
96
97 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_sync_hdr) + sizeof(struct smb2_negotiate_rsp))
98
get_neg_ctxt_len(struct smb2_sync_hdr * hdr,__u32 len,__u32 non_ctxlen)99 static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
100 __u32 non_ctxlen)
101 {
102 __u16 neg_count;
103 __u32 nc_offset, size_of_pad_before_neg_ctxts;
104 struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
105
106 /* Negotiate contexts are only valid for latest dialect SMB3.11 */
107 neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
108 if ((neg_count == 0) ||
109 (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
110 return 0;
111
112 /* Make sure that negotiate contexts start after gss security blob */
113 nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
114 if (nc_offset + 1 < non_ctxlen) {
115 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
116 return 0;
117 } else if (nc_offset + 1 == non_ctxlen) {
118 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
119 size_of_pad_before_neg_ctxts = 0;
120 } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
121 /* has padding, but no SPNEGO blob */
122 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
123 else
124 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
125
126 /* Verify that at least minimal negotiate contexts fit within frame */
127 if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
128 pr_warn_once("negotiate context goes beyond end\n");
129 return 0;
130 }
131
132 cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
133 len - nc_offset, size_of_pad_before_neg_ctxts);
134
135 /* length of negcontexts including pad from end of sec blob to them */
136 return (len - nc_offset) + size_of_pad_before_neg_ctxts;
137 }
138
139 int
smb2_check_message(char * buf,unsigned int len,struct TCP_Server_Info * srvr)140 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
141 {
142 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
143 struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
144 __u64 mid;
145 __u32 clc_len; /* calculated length */
146 int command;
147 int pdu_size = sizeof(struct smb2_sync_pdu);
148 int hdr_size = sizeof(struct smb2_sync_hdr);
149
150 /*
151 * Add function to do table lookup of StructureSize by command
152 * ie Validate the wct via smb2_struct_sizes table above
153 */
154 if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
155 struct smb2_transform_hdr *thdr =
156 (struct smb2_transform_hdr *)buf;
157 struct cifs_ses *ses = NULL;
158 struct list_head *tmp;
159
160 /* decrypt frame now that it is completely read in */
161 spin_lock(&cifs_tcp_ses_lock);
162 list_for_each(tmp, &srvr->smb_ses_list) {
163 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
164 if (ses->Suid == thdr->SessionId)
165 break;
166
167 ses = NULL;
168 }
169 spin_unlock(&cifs_tcp_ses_lock);
170 if (ses == NULL) {
171 cifs_dbg(VFS, "no decryption - session id not found\n");
172 return 1;
173 }
174 }
175
176 mid = le64_to_cpu(shdr->MessageId);
177 if (len < pdu_size) {
178 if ((len >= hdr_size)
179 && (shdr->Status != 0)) {
180 pdu->StructureSize2 = 0;
181 /*
182 * As with SMB/CIFS, on some error cases servers may
183 * not return wct properly
184 */
185 return 0;
186 } else {
187 cifs_dbg(VFS, "Length less than SMB header size\n");
188 }
189 return 1;
190 }
191 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
192 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
193 mid);
194 return 1;
195 }
196
197 if (check_smb2_hdr(shdr, mid))
198 return 1;
199
200 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
201 cifs_dbg(VFS, "Invalid structure size %u\n",
202 le16_to_cpu(shdr->StructureSize));
203 return 1;
204 }
205
206 command = le16_to_cpu(shdr->Command);
207 if (command >= NUMBER_OF_SMB2_COMMANDS) {
208 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
209 return 1;
210 }
211
212 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
213 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
214 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
215 /* error packets have 9 byte structure size */
216 cifs_dbg(VFS, "Invalid response size %u for command %d\n",
217 le16_to_cpu(pdu->StructureSize2), command);
218 return 1;
219 } else if (command == SMB2_OPLOCK_BREAK_HE
220 && (shdr->Status == 0)
221 && (le16_to_cpu(pdu->StructureSize2) != 44)
222 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
223 /* special case for SMB2.1 lease break message */
224 cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
225 le16_to_cpu(pdu->StructureSize2));
226 return 1;
227 }
228 }
229
230 clc_len = smb2_calc_size(buf, srvr);
231
232 if (shdr->Command == SMB2_NEGOTIATE)
233 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
234
235 if (len != clc_len) {
236 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
237 clc_len, len, mid);
238 /* create failed on symlink */
239 if (command == SMB2_CREATE_HE &&
240 shdr->Status == STATUS_STOPPED_ON_SYMLINK)
241 return 0;
242 /* Windows 7 server returns 24 bytes more */
243 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
244 return 0;
245 /* server can return one byte more due to implied bcc[0] */
246 if (clc_len == len + 1)
247 return 0;
248
249 /*
250 * Some windows servers (win2016) will pad also the final
251 * PDU in a compound to 8 bytes.
252 */
253 if (((clc_len + 7) & ~7) == len)
254 return 0;
255
256 /*
257 * MacOS server pads after SMB2.1 write response with 3 bytes
258 * of junk. Other servers match RFC1001 len to actual
259 * SMB2/SMB3 frame length (header + smb2 response specific data)
260 * Some windows servers also pad up to 8 bytes when compounding.
261 */
262 if (clc_len < len)
263 return 0;
264
265 pr_warn_once(
266 "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
267 len, clc_len, command, mid);
268
269 return 1;
270 }
271 return 0;
272 }
273
274 /*
275 * The size of the variable area depends on the offset and length fields
276 * located in different fields for various SMB2 responses. SMB2 responses
277 * with no variable length info, show an offset of zero for the offset field.
278 */
279 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
280 /* SMB2_NEGOTIATE */ true,
281 /* SMB2_SESSION_SETUP */ true,
282 /* SMB2_LOGOFF */ false,
283 /* SMB2_TREE_CONNECT */ false,
284 /* SMB2_TREE_DISCONNECT */ false,
285 /* SMB2_CREATE */ true,
286 /* SMB2_CLOSE */ false,
287 /* SMB2_FLUSH */ false,
288 /* SMB2_READ */ true,
289 /* SMB2_WRITE */ false,
290 /* SMB2_LOCK */ false,
291 /* SMB2_IOCTL */ true,
292 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
293 /* SMB2_ECHO */ false,
294 /* SMB2_QUERY_DIRECTORY */ true,
295 /* SMB2_CHANGE_NOTIFY */ true,
296 /* SMB2_QUERY_INFO */ true,
297 /* SMB2_SET_INFO */ false,
298 /* SMB2_OPLOCK_BREAK */ false
299 };
300
301 /*
302 * Returns the pointer to the beginning of the data area. Length of the data
303 * area and the offset to it (from the beginning of the smb are also returned.
304 */
305 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_sync_hdr * shdr)306 smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
307 {
308 const int max_off = 4096;
309 const int max_len = 128 * 1024;
310
311 *off = 0;
312 *len = 0;
313
314 /* error responses do not have data area */
315 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
316 (((struct smb2_err_rsp *)shdr)->StructureSize) ==
317 SMB2_ERROR_STRUCTURE_SIZE2)
318 return NULL;
319
320 /*
321 * Following commands have data areas so we have to get the location
322 * of the data buffer offset and data buffer length for the particular
323 * command.
324 */
325 switch (shdr->Command) {
326 case SMB2_NEGOTIATE:
327 *off = le16_to_cpu(
328 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
329 *len = le16_to_cpu(
330 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
331 break;
332 case SMB2_SESSION_SETUP:
333 *off = le16_to_cpu(
334 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
335 *len = le16_to_cpu(
336 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
337 break;
338 case SMB2_CREATE:
339 *off = le32_to_cpu(
340 ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
341 *len = le32_to_cpu(
342 ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
343 break;
344 case SMB2_QUERY_INFO:
345 *off = le16_to_cpu(
346 ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
347 *len = le32_to_cpu(
348 ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
349 break;
350 case SMB2_READ:
351 /* TODO: is this a bug ? */
352 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
353 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
354 break;
355 case SMB2_QUERY_DIRECTORY:
356 *off = le16_to_cpu(
357 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
358 *len = le32_to_cpu(
359 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
360 break;
361 case SMB2_IOCTL:
362 *off = le32_to_cpu(
363 ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
364 *len = le32_to_cpu(
365 ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
366 break;
367 case SMB2_CHANGE_NOTIFY:
368 *off = le16_to_cpu(
369 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
370 *len = le32_to_cpu(
371 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
372 break;
373 default:
374 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
375 break;
376 }
377
378 /*
379 * Invalid length or offset probably means data area is invalid, but
380 * we have little choice but to ignore the data area in this case.
381 */
382 if (unlikely(*off < 0 || *off > max_off ||
383 *len < 0 || *len > max_len)) {
384 cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
385 __func__, *off, *len);
386 *off = 0;
387 *len = 0;
388 } else if (*off == 0) {
389 *len = 0;
390 }
391
392 /* return pointer to beginning of data area, ie offset from SMB start */
393 if (*off > 0 && *len > 0)
394 return (char *)shdr + *off;
395 return NULL;
396 }
397
398 /*
399 * Calculate the size of the SMB message based on the fixed header
400 * portion, the number of word parameters and the data portion of the message.
401 */
402 unsigned int
smb2_calc_size(void * buf,struct TCP_Server_Info * srvr)403 smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
404 {
405 struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
406 struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
407 int offset; /* the offset from the beginning of SMB to data area */
408 int data_length; /* the length of the variable length data area */
409 /* Structure Size has already been checked to make sure it is 64 */
410 int len = le16_to_cpu(shdr->StructureSize);
411
412 /*
413 * StructureSize2, ie length of fixed parameter area has already
414 * been checked to make sure it is the correct length.
415 */
416 len += le16_to_cpu(pdu->StructureSize2);
417
418 if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
419 goto calc_size_exit;
420
421 smb2_get_data_area_len(&offset, &data_length, shdr);
422 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
423
424 if (data_length > 0) {
425 /*
426 * Check to make sure that data area begins after fixed area,
427 * Note that last byte of the fixed area is part of data area
428 * for some commands, typically those with odd StructureSize,
429 * so we must add one to the calculation.
430 */
431 if (offset + 1 < len) {
432 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
433 offset + 1, len);
434 data_length = 0;
435 } else {
436 len = offset + data_length;
437 }
438 }
439 calc_size_exit:
440 cifs_dbg(FYI, "SMB2 len %d\n", len);
441 return len;
442 }
443
444 /* Note: caller must free return buffer */
445 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)446 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
447 {
448 int len;
449 const char *start_of_path;
450 __le16 *to;
451 int map_type;
452
453 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
454 map_type = SFM_MAP_UNI_RSVD;
455 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
456 map_type = SFU_MAP_UNI_RSVD;
457 else
458 map_type = NO_MAP_UNI_RSVD;
459
460 /* Windows doesn't allow paths beginning with \ */
461 if (from[0] == '\\')
462 start_of_path = from + 1;
463
464 /* SMB311 POSIX extensions paths do not include leading slash */
465 else if (cifs_sb_master_tlink(cifs_sb) &&
466 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
467 (from[0] == '/')) {
468 start_of_path = from + 1;
469 } else
470 start_of_path = from;
471
472 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
473 cifs_sb->local_nls, map_type);
474 return to;
475 }
476
477 __le32
smb2_get_lease_state(struct cifsInodeInfo * cinode)478 smb2_get_lease_state(struct cifsInodeInfo *cinode)
479 {
480 __le32 lease = 0;
481
482 if (CIFS_CACHE_WRITE(cinode))
483 lease |= SMB2_LEASE_WRITE_CACHING;
484 if (CIFS_CACHE_HANDLE(cinode))
485 lease |= SMB2_LEASE_HANDLE_CACHING;
486 if (CIFS_CACHE_READ(cinode))
487 lease |= SMB2_LEASE_READ_CACHING;
488 return lease;
489 }
490
491 struct smb2_lease_break_work {
492 struct work_struct lease_break;
493 struct tcon_link *tlink;
494 __u8 lease_key[16];
495 __le32 lease_state;
496 };
497
498 static void
cifs_ses_oplock_break(struct work_struct * work)499 cifs_ses_oplock_break(struct work_struct *work)
500 {
501 struct smb2_lease_break_work *lw = container_of(work,
502 struct smb2_lease_break_work, lease_break);
503 int rc = 0;
504
505 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
506 lw->lease_state);
507
508 cifs_dbg(FYI, "Lease release rc %d\n", rc);
509 cifs_put_tlink(lw->tlink);
510 kfree(lw);
511 }
512
513 static void
smb2_queue_pending_open_break(struct tcon_link * tlink,__u8 * lease_key,__le32 new_lease_state)514 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
515 __le32 new_lease_state)
516 {
517 struct smb2_lease_break_work *lw;
518
519 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
520 if (!lw) {
521 cifs_put_tlink(tlink);
522 return;
523 }
524
525 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
526 lw->tlink = tlink;
527 lw->lease_state = new_lease_state;
528 memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
529 queue_work(cifsiod_wq, &lw->lease_break);
530 }
531
532 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)533 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
534 {
535 __u8 lease_state;
536 struct list_head *tmp;
537 struct cifsFileInfo *cfile;
538 struct cifsInodeInfo *cinode;
539 int ack_req = le32_to_cpu(rsp->Flags &
540 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
541
542 lease_state = le32_to_cpu(rsp->NewLeaseState);
543
544 list_for_each(tmp, &tcon->openFileList) {
545 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
546 cinode = CIFS_I(d_inode(cfile->dentry));
547
548 if (memcmp(cinode->lease_key, rsp->LeaseKey,
549 SMB2_LEASE_KEY_SIZE))
550 continue;
551
552 cifs_dbg(FYI, "found in the open list\n");
553 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
554 lease_state);
555
556 if (ack_req)
557 cfile->oplock_break_cancelled = false;
558 else
559 cfile->oplock_break_cancelled = true;
560
561 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
562
563 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
564 cfile->oplock_level = lease_state;
565
566 cifs_queue_oplock_break(cfile);
567 return true;
568 }
569
570 return false;
571 }
572
573 static struct cifs_pending_open *
smb2_tcon_find_pending_open_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)574 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
575 struct smb2_lease_break *rsp)
576 {
577 __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
578 int ack_req = le32_to_cpu(rsp->Flags &
579 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
580 struct cifs_pending_open *open;
581 struct cifs_pending_open *found = NULL;
582
583 list_for_each_entry(open, &tcon->pending_opens, olist) {
584 if (memcmp(open->lease_key, rsp->LeaseKey,
585 SMB2_LEASE_KEY_SIZE))
586 continue;
587
588 if (!found && ack_req) {
589 found = open;
590 }
591
592 cifs_dbg(FYI, "found in the pending open list\n");
593 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
594 lease_state);
595
596 open->oplock = lease_state;
597 }
598
599 return found;
600 }
601
602 static bool
smb2_is_valid_lease_break(char * buffer)603 smb2_is_valid_lease_break(char *buffer)
604 {
605 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
606 struct list_head *tmp, *tmp1, *tmp2;
607 struct TCP_Server_Info *server;
608 struct cifs_ses *ses;
609 struct cifs_tcon *tcon;
610 struct cifs_pending_open *open;
611
612 cifs_dbg(FYI, "Checking for lease break\n");
613
614 /* look up tcon based on tid & uid */
615 spin_lock(&cifs_tcp_ses_lock);
616 list_for_each(tmp, &cifs_tcp_ses_list) {
617 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
618
619 list_for_each(tmp1, &server->smb_ses_list) {
620 ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
621
622 list_for_each(tmp2, &ses->tcon_list) {
623 tcon = list_entry(tmp2, struct cifs_tcon,
624 tcon_list);
625 spin_lock(&tcon->open_file_lock);
626 cifs_stats_inc(
627 &tcon->stats.cifs_stats.num_oplock_brks);
628 if (smb2_tcon_has_lease(tcon, rsp)) {
629 spin_unlock(&tcon->open_file_lock);
630 spin_unlock(&cifs_tcp_ses_lock);
631 return true;
632 }
633 open = smb2_tcon_find_pending_open_lease(tcon,
634 rsp);
635 if (open) {
636 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
637 struct tcon_link *tlink;
638
639 tlink = cifs_get_tlink(open->tlink);
640 memcpy(lease_key, open->lease_key,
641 SMB2_LEASE_KEY_SIZE);
642 spin_unlock(&tcon->open_file_lock);
643 spin_unlock(&cifs_tcp_ses_lock);
644 smb2_queue_pending_open_break(tlink,
645 lease_key,
646 rsp->NewLeaseState);
647 return true;
648 }
649 spin_unlock(&tcon->open_file_lock);
650
651 if (tcon->crfid.is_valid &&
652 !memcmp(rsp->LeaseKey,
653 tcon->crfid.fid->lease_key,
654 SMB2_LEASE_KEY_SIZE)) {
655 INIT_WORK(&tcon->crfid.lease_break,
656 smb2_cached_lease_break);
657 queue_work(cifsiod_wq,
658 &tcon->crfid.lease_break);
659 spin_unlock(&cifs_tcp_ses_lock);
660 return true;
661 }
662 }
663 }
664 }
665 spin_unlock(&cifs_tcp_ses_lock);
666 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
667 return false;
668 }
669
670 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)671 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
672 {
673 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
674 struct list_head *tmp, *tmp1, *tmp2;
675 struct cifs_ses *ses;
676 struct cifs_tcon *tcon;
677 struct cifsInodeInfo *cinode;
678 struct cifsFileInfo *cfile;
679
680 cifs_dbg(FYI, "Checking for oplock break\n");
681
682 if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
683 return false;
684
685 if (rsp->StructureSize !=
686 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
687 if (le16_to_cpu(rsp->StructureSize) == 44)
688 return smb2_is_valid_lease_break(buffer);
689 else
690 return false;
691 }
692
693 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
694
695 /* look up tcon based on tid & uid */
696 spin_lock(&cifs_tcp_ses_lock);
697 list_for_each(tmp, &server->smb_ses_list) {
698 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
699
700 list_for_each(tmp1, &ses->tcon_list) {
701 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
702
703 spin_lock(&tcon->open_file_lock);
704 list_for_each(tmp2, &tcon->openFileList) {
705 cfile = list_entry(tmp2, struct cifsFileInfo,
706 tlist);
707 if (rsp->PersistentFid !=
708 cfile->fid.persistent_fid ||
709 rsp->VolatileFid !=
710 cfile->fid.volatile_fid)
711 continue;
712
713 cifs_dbg(FYI, "file id match, oplock break\n");
714 cifs_stats_inc(
715 &tcon->stats.cifs_stats.num_oplock_brks);
716 cinode = CIFS_I(d_inode(cfile->dentry));
717 spin_lock(&cfile->file_info_lock);
718 if (!CIFS_CACHE_WRITE(cinode) &&
719 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
720 cfile->oplock_break_cancelled = true;
721 else
722 cfile->oplock_break_cancelled = false;
723
724 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
725 &cinode->flags);
726
727 cfile->oplock_epoch = 0;
728 cfile->oplock_level = rsp->OplockLevel;
729
730 spin_unlock(&cfile->file_info_lock);
731
732 cifs_queue_oplock_break(cfile);
733
734 spin_unlock(&tcon->open_file_lock);
735 spin_unlock(&cifs_tcp_ses_lock);
736 return true;
737 }
738 spin_unlock(&tcon->open_file_lock);
739 }
740 }
741 spin_unlock(&cifs_tcp_ses_lock);
742 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
743 return true;
744 }
745
746 void
smb2_cancelled_close_fid(struct work_struct * work)747 smb2_cancelled_close_fid(struct work_struct *work)
748 {
749 struct close_cancelled_open *cancelled = container_of(work,
750 struct close_cancelled_open, work);
751 struct cifs_tcon *tcon = cancelled->tcon;
752 int rc;
753
754 if (cancelled->mid)
755 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llx\n",
756 cancelled->mid);
757 else
758 cifs_tcon_dbg(VFS, "Close interrupted close\n");
759
760 rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
761 cancelled->fid.volatile_fid);
762 if (rc)
763 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
764
765 cifs_put_tcon(tcon);
766 kfree(cancelled);
767 }
768
769 /*
770 * Caller should already has an extra reference to @tcon
771 * This function is used to queue work to close a handle to prevent leaks
772 * on the server.
773 * We handle two cases. If an open was interrupted after we sent the
774 * SMB2_CREATE to the server but before we processed the reply, and second
775 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
776 */
777 static int
__smb2_handle_cancelled_cmd(struct cifs_tcon * tcon,__u16 cmd,__u64 mid,__u64 persistent_fid,__u64 volatile_fid)778 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
779 __u64 persistent_fid, __u64 volatile_fid)
780 {
781 struct close_cancelled_open *cancelled;
782
783 cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
784 if (!cancelled)
785 return -ENOMEM;
786
787 cancelled->fid.persistent_fid = persistent_fid;
788 cancelled->fid.volatile_fid = volatile_fid;
789 cancelled->tcon = tcon;
790 cancelled->cmd = cmd;
791 cancelled->mid = mid;
792 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
793 WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
794
795 return 0;
796 }
797
798 int
smb2_handle_cancelled_close(struct cifs_tcon * tcon,__u64 persistent_fid,__u64 volatile_fid)799 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
800 __u64 volatile_fid)
801 {
802 int rc;
803
804 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
805 spin_lock(&cifs_tcp_ses_lock);
806 if (tcon->tc_count <= 0) {
807 struct TCP_Server_Info *server = NULL;
808
809 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
810 spin_unlock(&cifs_tcp_ses_lock);
811
812 if (tcon->ses)
813 server = tcon->ses->server;
814
815 cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
816 tcon->tid, persistent_fid, volatile_fid);
817
818 return 0;
819 }
820 tcon->tc_count++;
821 spin_unlock(&cifs_tcp_ses_lock);
822
823 rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
824 persistent_fid, volatile_fid);
825 if (rc)
826 cifs_put_tcon(tcon);
827
828 return rc;
829 }
830
831 int
smb2_handle_cancelled_mid(struct mid_q_entry * mid,struct TCP_Server_Info * server)832 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
833 {
834 struct smb2_sync_hdr *sync_hdr = mid->resp_buf;
835 struct smb2_create_rsp *rsp = mid->resp_buf;
836 struct cifs_tcon *tcon;
837 int rc;
838
839 if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || sync_hdr->Command != SMB2_CREATE ||
840 sync_hdr->Status != STATUS_SUCCESS)
841 return 0;
842
843 tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
844 sync_hdr->TreeId);
845 if (!tcon)
846 return -ENOENT;
847
848 rc = __smb2_handle_cancelled_cmd(tcon,
849 le16_to_cpu(sync_hdr->Command),
850 le64_to_cpu(sync_hdr->MessageId),
851 rsp->PersistentFileId,
852 rsp->VolatileFileId);
853 if (rc)
854 cifs_put_tcon(tcon);
855
856 return rc;
857 }
858
859 /**
860 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
861 *
862 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
863 * SMB2 header.
864 */
865 int
smb311_update_preauth_hash(struct cifs_ses * ses,struct kvec * iov,int nvec)866 smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
867 {
868 int i, rc;
869 struct sdesc *d;
870 struct smb2_sync_hdr *hdr;
871 struct TCP_Server_Info *server = cifs_ses_server(ses);
872
873 hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
874 /* neg prot are always taken */
875 if (hdr->Command == SMB2_NEGOTIATE)
876 goto ok;
877
878 /*
879 * If we process a command which wasn't a negprot it means the
880 * neg prot was already done, so the server dialect was set
881 * and we can test it. Preauth requires 3.1.1 for now.
882 */
883 if (server->dialect != SMB311_PROT_ID)
884 return 0;
885
886 if (hdr->Command != SMB2_SESSION_SETUP)
887 return 0;
888
889 /* skip last sess setup response */
890 if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
891 && (hdr->Status == NT_STATUS_OK
892 || (hdr->Status !=
893 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
894 return 0;
895
896 ok:
897 rc = smb311_crypto_shash_allocate(server);
898 if (rc)
899 return rc;
900
901 d = server->secmech.sdescsha512;
902 rc = crypto_shash_init(&d->shash);
903 if (rc) {
904 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
905 return rc;
906 }
907
908 rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
909 SMB2_PREAUTH_HASH_SIZE);
910 if (rc) {
911 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
912 return rc;
913 }
914
915 for (i = 0; i < nvec; i++) {
916 rc = crypto_shash_update(&d->shash,
917 iov[i].iov_base, iov[i].iov_len);
918 if (rc) {
919 cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
920 __func__);
921 return rc;
922 }
923 }
924
925 rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
926 if (rc) {
927 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
928 __func__);
929 return rc;
930 }
931
932 return 0;
933 }
934