1 // SPDX-License-Identifier: LGPL-2.1
2 /*
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 */
10 #include <linux/ctype.h>
11 #include "cifsglob.h"
12 #include "cifsproto.h"
13 #include "smb2proto.h"
14 #include "cifs_debug.h"
15 #include "cifs_unicode.h"
16 #include "smb2status.h"
17 #include "smb2glob.h"
18 #include "nterr.h"
19 #include "cached_dir.h"
20
21 static int
22 check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
23 {
24 __u64 wire_mid = le64_to_cpu(shdr->MessageId);
25
26 /*
27 * Make sure that this really is an SMB, that it is a response,
28 * and that the message ids match.
29 */
30 if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
31 (mid == wire_mid)) {
32 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
33 return 0;
34 else {
35 /* only one valid case where server sends us request */
36 if (shdr->Command == SMB2_OPLOCK_BREAK)
37 return 0;
38 else
39 cifs_dbg(VFS, "Received Request not response\n");
40 }
41 } else { /* bad signature or mid */
42 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
43 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
44 le32_to_cpu(shdr->ProtocolId));
45 if (mid != wire_mid)
46 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
47 mid, wire_mid);
48 }
49 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
50 return 1;
51 }
52
53 /*
54 * The following table defines the expected "StructureSize" of SMB2 responses
55 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
56 *
57 * Note that commands are defined in smb2pdu.h in le16 but the array below is
58 * indexed by command in host byte order
59 */
60 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
61 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
62 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
63 /* SMB2_LOGOFF */ cpu_to_le16(4),
64 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
65 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
66 /* SMB2_CREATE */ cpu_to_le16(89),
67 /* SMB2_CLOSE */ cpu_to_le16(60),
68 /* SMB2_FLUSH */ cpu_to_le16(4),
69 /* SMB2_READ */ cpu_to_le16(17),
70 /* SMB2_WRITE */ cpu_to_le16(17),
71 /* SMB2_LOCK */ cpu_to_le16(4),
72 /* SMB2_IOCTL */ cpu_to_le16(49),
73 /* BB CHECK this ... not listed in documentation */
74 /* SMB2_CANCEL */ cpu_to_le16(0),
75 /* SMB2_ECHO */ cpu_to_le16(4),
76 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
77 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
78 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
79 /* SMB2_SET_INFO */ cpu_to_le16(2),
80 /* BB FIXME can also be 44 for lease break */
81 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
82 };
83
84 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
85
86 static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
87 __u32 non_ctxlen)
88 {
89 __u16 neg_count;
90 __u32 nc_offset, size_of_pad_before_neg_ctxts;
91 struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
92
93 /* Negotiate contexts are only valid for latest dialect SMB3.11 */
94 neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
95 if ((neg_count == 0) ||
96 (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
97 return 0;
98
99 /*
100 * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
101 * which security mechanisms the server supports) make sure that
102 * the negotiate contexts start after it
103 */
104 nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
105 /*
106 * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
107 * and the latter is 1 byte bigger than the fix-sized area of the
108 * NEGOTIATE response
109 */
110 if (nc_offset + 1 < non_ctxlen) {
111 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
112 return 0;
113 } else if (nc_offset + 1 == non_ctxlen) {
114 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
115 size_of_pad_before_neg_ctxts = 0;
116 } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
117 /* has padding, but no SPNEGO blob */
118 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
119 else
120 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
121
122 /* Verify that at least minimal negotiate contexts fit within frame */
123 if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
124 pr_warn_once("negotiate context goes beyond end\n");
125 return 0;
126 }
127
128 cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
129 len - nc_offset, size_of_pad_before_neg_ctxts);
130
131 /* length of negcontexts including pad from end of sec blob to them */
132 return (len - nc_offset) + size_of_pad_before_neg_ctxts;
133 }
134
135 int
136 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
137 {
138 struct TCP_Server_Info *pserver;
139 struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
140 struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
141 int hdr_size = sizeof(struct smb2_hdr);
142 int pdu_size = sizeof(struct smb2_pdu);
143 int command;
144 __u32 calc_len; /* calculated length */
145 __u64 mid;
146
147 /* If server is a channel, select the primary channel */
148 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
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 cifs_ses *iter;
159
160 /* decrypt frame now that it is completely read in */
161 spin_lock(&cifs_tcp_ses_lock);
162 list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
163 if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
164 ses = iter;
165 break;
166 }
167 }
168 spin_unlock(&cifs_tcp_ses_lock);
169 if (!ses) {
170 cifs_dbg(VFS, "no decryption - session id not found\n");
171 return 1;
172 }
173 }
174
175 mid = le64_to_cpu(shdr->MessageId);
176 if (check_smb2_hdr(shdr, mid))
177 return 1;
178
179 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
180 cifs_dbg(VFS, "Invalid structure size %u\n",
181 le16_to_cpu(shdr->StructureSize));
182 return 1;
183 }
184
185 command = le16_to_cpu(shdr->Command);
186 if (command >= NUMBER_OF_SMB2_COMMANDS) {
187 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
188 return 1;
189 }
190
191 if (len < pdu_size) {
192 if ((len >= hdr_size)
193 && (shdr->Status != 0)) {
194 pdu->StructureSize2 = 0;
195 /*
196 * As with SMB/CIFS, on some error cases servers may
197 * not return wct properly
198 */
199 return 0;
200 } else {
201 cifs_dbg(VFS, "Length less than SMB header size\n");
202 }
203 return 1;
204 }
205 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
206 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
207 mid);
208 return 1;
209 }
210
211 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
212 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
213 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
214 /* error packets have 9 byte structure size */
215 cifs_dbg(VFS, "Invalid response size %u for command %d\n",
216 le16_to_cpu(pdu->StructureSize2), command);
217 return 1;
218 } else if (command == SMB2_OPLOCK_BREAK_HE
219 && (shdr->Status == 0)
220 && (le16_to_cpu(pdu->StructureSize2) != 44)
221 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
222 /* special case for SMB2.1 lease break message */
223 cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
224 le16_to_cpu(pdu->StructureSize2));
225 return 1;
226 }
227 }
228
229 calc_len = smb2_calc_size(buf);
230
231 /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
232 * be 0, and not a real miscalculation */
233 if (command == SMB2_IOCTL_HE && calc_len == 0)
234 return 0;
235
236 if (command == SMB2_NEGOTIATE_HE)
237 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
238
239 if (len != calc_len) {
240 /* create failed on symlink */
241 if (command == SMB2_CREATE_HE &&
242 shdr->Status == STATUS_STOPPED_ON_SYMLINK)
243 return 0;
244 /* Windows 7 server returns 24 bytes more */
245 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
246 return 0;
247 /* server can return one byte more due to implied bcc[0] */
248 if (calc_len == len + 1)
249 return 0;
250
251 /*
252 * Some windows servers (win2016) will pad also the final
253 * PDU in a compound to 8 bytes.
254 */
255 if (ALIGN(calc_len, 8) == len)
256 return 0;
257
258 /*
259 * MacOS server pads after SMB2.1 write response with 3 bytes
260 * of junk. Other servers match RFC1001 len to actual
261 * SMB2/SMB3 frame length (header + smb2 response specific data)
262 * Some windows servers also pad up to 8 bytes when compounding.
263 */
264 if (calc_len < len)
265 return 0;
266
267 /* Only log a message if len was really miscalculated */
268 if (unlikely(cifsFYI))
269 cifs_dbg(FYI, "Server response too short: calculated "
270 "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
271 calc_len, len, command, mid);
272 else
273 pr_warn("Server response too short: calculated length "
274 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
275 calc_len, len, command, mid);
276
277 return 1;
278 }
279 return 0;
280 }
281
282 /*
283 * The size of the variable area depends on the offset and length fields
284 * located in different fields for various SMB2 responses. SMB2 responses
285 * with no variable length info, show an offset of zero for the offset field.
286 */
287 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
288 /* SMB2_NEGOTIATE */ true,
289 /* SMB2_SESSION_SETUP */ true,
290 /* SMB2_LOGOFF */ false,
291 /* SMB2_TREE_CONNECT */ false,
292 /* SMB2_TREE_DISCONNECT */ false,
293 /* SMB2_CREATE */ true,
294 /* SMB2_CLOSE */ false,
295 /* SMB2_FLUSH */ false,
296 /* SMB2_READ */ true,
297 /* SMB2_WRITE */ false,
298 /* SMB2_LOCK */ false,
299 /* SMB2_IOCTL */ true,
300 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
301 /* SMB2_ECHO */ false,
302 /* SMB2_QUERY_DIRECTORY */ true,
303 /* SMB2_CHANGE_NOTIFY */ true,
304 /* SMB2_QUERY_INFO */ true,
305 /* SMB2_SET_INFO */ false,
306 /* SMB2_OPLOCK_BREAK */ false
307 };
308
309 /*
310 * Returns the pointer to the beginning of the data area. Length of the data
311 * area and the offset to it (from the beginning of the smb are also returned.
312 */
313 char *
314 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
315 {
316 const int max_off = 4096;
317 const int max_len = 128 * 1024;
318
319 *off = 0;
320 *len = 0;
321
322 /* error responses do not have data area */
323 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
324 (((struct smb2_err_rsp *)shdr)->StructureSize) ==
325 SMB2_ERROR_STRUCTURE_SIZE2_LE)
326 return NULL;
327
328 /*
329 * Following commands have data areas so we have to get the location
330 * of the data buffer offset and data buffer length for the particular
331 * command.
332 */
333 switch (shdr->Command) {
334 case SMB2_NEGOTIATE:
335 *off = le16_to_cpu(
336 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
337 *len = le16_to_cpu(
338 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
339 break;
340 case SMB2_SESSION_SETUP:
341 *off = le16_to_cpu(
342 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
343 *len = le16_to_cpu(
344 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
345 break;
346 case SMB2_CREATE:
347 *off = le32_to_cpu(
348 ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
349 *len = le32_to_cpu(
350 ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
351 break;
352 case SMB2_QUERY_INFO:
353 *off = le16_to_cpu(
354 ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
355 *len = le32_to_cpu(
356 ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
357 break;
358 case SMB2_READ:
359 /* TODO: is this a bug ? */
360 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
361 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
362 break;
363 case SMB2_QUERY_DIRECTORY:
364 *off = le16_to_cpu(
365 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
366 *len = le32_to_cpu(
367 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
368 break;
369 case SMB2_IOCTL:
370 *off = le32_to_cpu(
371 ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
372 *len = le32_to_cpu(
373 ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
374 break;
375 case SMB2_CHANGE_NOTIFY:
376 *off = le16_to_cpu(
377 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
378 *len = le32_to_cpu(
379 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
380 break;
381 default:
382 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
383 break;
384 }
385
386 /*
387 * Invalid length or offset probably means data area is invalid, but
388 * we have little choice but to ignore the data area in this case.
389 */
390 if (unlikely(*off < 0 || *off > max_off ||
391 *len < 0 || *len > max_len)) {
392 cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
393 __func__, *off, *len);
394 *off = 0;
395 *len = 0;
396 } else if (*off == 0) {
397 *len = 0;
398 }
399
400 /* return pointer to beginning of data area, ie offset from SMB start */
401 if (*off > 0 && *len > 0)
402 return (char *)shdr + *off;
403 return NULL;
404 }
405
406 /*
407 * Calculate the size of the SMB message based on the fixed header
408 * portion, the number of word parameters and the data portion of the message.
409 */
410 unsigned int
411 smb2_calc_size(void *buf)
412 {
413 struct smb2_pdu *pdu = buf;
414 struct smb2_hdr *shdr = &pdu->hdr;
415 int offset; /* the offset from the beginning of SMB to data area */
416 int data_length; /* the length of the variable length data area */
417 /* Structure Size has already been checked to make sure it is 64 */
418 int len = le16_to_cpu(shdr->StructureSize);
419
420 /*
421 * StructureSize2, ie length of fixed parameter area has already
422 * been checked to make sure it is the correct length.
423 */
424 len += le16_to_cpu(pdu->StructureSize2);
425
426 if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
427 goto calc_size_exit;
428
429 smb2_get_data_area_len(&offset, &data_length, shdr);
430 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
431
432 if (data_length > 0) {
433 /*
434 * Check to make sure that data area begins after fixed area,
435 * Note that last byte of the fixed area is part of data area
436 * for some commands, typically those with odd StructureSize,
437 * so we must add one to the calculation.
438 */
439 if (offset + 1 < len) {
440 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
441 offset + 1, len);
442 data_length = 0;
443 } else {
444 len = offset + data_length;
445 }
446 }
447 calc_size_exit:
448 cifs_dbg(FYI, "SMB2 len %d\n", len);
449 return len;
450 }
451
452 /* Note: caller must free return buffer */
453 __le16 *
454 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
455 {
456 int len;
457 const char *start_of_path;
458 __le16 *to;
459 int map_type;
460
461 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
462 map_type = SFM_MAP_UNI_RSVD;
463 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
464 map_type = SFU_MAP_UNI_RSVD;
465 else
466 map_type = NO_MAP_UNI_RSVD;
467
468 /* Windows doesn't allow paths beginning with \ */
469 if (from[0] == '\\')
470 start_of_path = from + 1;
471
472 /* SMB311 POSIX extensions paths do not include leading slash */
473 else if (cifs_sb_master_tlink(cifs_sb) &&
474 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
475 (from[0] == '/')) {
476 start_of_path = from + 1;
477 } else
478 start_of_path = from;
479
480 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
481 cifs_sb->local_nls, map_type);
482 return to;
483 }
484
485 __le32
486 smb2_get_lease_state(struct cifsInodeInfo *cinode)
487 {
488 __le32 lease = 0;
489
490 if (CIFS_CACHE_WRITE(cinode))
491 lease |= SMB2_LEASE_WRITE_CACHING_LE;
492 if (CIFS_CACHE_HANDLE(cinode))
493 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
494 if (CIFS_CACHE_READ(cinode))
495 lease |= SMB2_LEASE_READ_CACHING_LE;
496 return lease;
497 }
498
499 struct smb2_lease_break_work {
500 struct work_struct lease_break;
501 struct tcon_link *tlink;
502 __u8 lease_key[16];
503 __le32 lease_state;
504 };
505
506 static void
507 cifs_ses_oplock_break(struct work_struct *work)
508 {
509 struct smb2_lease_break_work *lw = container_of(work,
510 struct smb2_lease_break_work, lease_break);
511 int rc = 0;
512
513 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
514 lw->lease_state);
515
516 cifs_dbg(FYI, "Lease release rc %d\n", rc);
517 cifs_put_tlink(lw->tlink);
518 kfree(lw);
519 }
520
521 static void
522 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
523 __le32 new_lease_state)
524 {
525 struct smb2_lease_break_work *lw;
526
527 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
528 if (!lw) {
529 cifs_put_tlink(tlink);
530 return;
531 }
532
533 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
534 lw->tlink = tlink;
535 lw->lease_state = new_lease_state;
536 memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
537 queue_work(cifsiod_wq, &lw->lease_break);
538 }
539
540 static bool
541 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
542 {
543 __u8 lease_state;
544 struct cifsFileInfo *cfile;
545 struct cifsInodeInfo *cinode;
546 int ack_req = le32_to_cpu(rsp->Flags &
547 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
548
549 lease_state = le32_to_cpu(rsp->NewLeaseState);
550
551 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
552 cinode = CIFS_I(d_inode(cfile->dentry));
553
554 if (memcmp(cinode->lease_key, rsp->LeaseKey,
555 SMB2_LEASE_KEY_SIZE))
556 continue;
557
558 cifs_dbg(FYI, "found in the open list\n");
559 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
560 lease_state);
561
562 if (ack_req)
563 cfile->oplock_break_cancelled = false;
564 else
565 cfile->oplock_break_cancelled = true;
566
567 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
568
569 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
570 cfile->oplock_level = lease_state;
571
572 cifs_queue_oplock_break(cfile);
573 return true;
574 }
575
576 return false;
577 }
578
579 static struct cifs_pending_open *
580 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
581 struct smb2_lease_break *rsp)
582 {
583 __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
584 int ack_req = le32_to_cpu(rsp->Flags &
585 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
586 struct cifs_pending_open *open;
587 struct cifs_pending_open *found = NULL;
588
589 list_for_each_entry(open, &tcon->pending_opens, olist) {
590 if (memcmp(open->lease_key, rsp->LeaseKey,
591 SMB2_LEASE_KEY_SIZE))
592 continue;
593
594 if (!found && ack_req) {
595 found = open;
596 }
597
598 cifs_dbg(FYI, "found in the pending open list\n");
599 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
600 lease_state);
601
602 open->oplock = lease_state;
603 }
604
605 return found;
606 }
607
608 static bool
609 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
610 {
611 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
612 struct TCP_Server_Info *pserver;
613 struct cifs_ses *ses;
614 struct cifs_tcon *tcon;
615 struct cifs_pending_open *open;
616
617 cifs_dbg(FYI, "Checking for lease break\n");
618
619 /* If server is a channel, select the primary channel */
620 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
621
622 /* look up tcon based on tid & uid */
623 spin_lock(&cifs_tcp_ses_lock);
624 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
625 if (cifs_ses_exiting(ses))
626 continue;
627 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
628 spin_lock(&tcon->open_file_lock);
629 cifs_stats_inc(
630 &tcon->stats.cifs_stats.num_oplock_brks);
631 if (smb2_tcon_has_lease(tcon, rsp)) {
632 spin_unlock(&tcon->open_file_lock);
633 spin_unlock(&cifs_tcp_ses_lock);
634 return true;
635 }
636 open = smb2_tcon_find_pending_open_lease(tcon,
637 rsp);
638 if (open) {
639 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
640 struct tcon_link *tlink;
641
642 tlink = cifs_get_tlink(open->tlink);
643 memcpy(lease_key, open->lease_key,
644 SMB2_LEASE_KEY_SIZE);
645 spin_unlock(&tcon->open_file_lock);
646 spin_unlock(&cifs_tcp_ses_lock);
647 smb2_queue_pending_open_break(tlink,
648 lease_key,
649 rsp->NewLeaseState);
650 return true;
651 }
652 spin_unlock(&tcon->open_file_lock);
653
654 if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
655 spin_unlock(&cifs_tcp_ses_lock);
656 return true;
657 }
658 }
659 }
660 spin_unlock(&cifs_tcp_ses_lock);
661 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
662 trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
663 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
664 le64_to_cpu(rsp->hdr.SessionId),
665 *((u64 *)rsp->LeaseKey),
666 *((u64 *)&rsp->LeaseKey[8]));
667
668 return false;
669 }
670
671 bool
672 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
673 {
674 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
675 struct TCP_Server_Info *pserver;
676 struct cifs_ses *ses;
677 struct cifs_tcon *tcon;
678 struct cifsInodeInfo *cinode;
679 struct cifsFileInfo *cfile;
680
681 cifs_dbg(FYI, "Checking for oplock break\n");
682
683 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
684 return false;
685
686 if (rsp->StructureSize !=
687 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
688 if (le16_to_cpu(rsp->StructureSize) == 44)
689 return smb2_is_valid_lease_break(buffer, server);
690 else
691 return false;
692 }
693
694 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
695
696 /* If server is a channel, select the primary channel */
697 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
698
699 /* look up tcon based on tid & uid */
700 spin_lock(&cifs_tcp_ses_lock);
701 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
702 if (cifs_ses_exiting(ses))
703 continue;
704 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
705
706 spin_lock(&tcon->open_file_lock);
707 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
708 if (rsp->PersistentFid !=
709 cfile->fid.persistent_fid ||
710 rsp->VolatileFid !=
711 cfile->fid.volatile_fid)
712 continue;
713
714 cifs_dbg(FYI, "file id match, oplock break\n");
715 cifs_stats_inc(
716 &tcon->stats.cifs_stats.num_oplock_brks);
717 cinode = CIFS_I(d_inode(cfile->dentry));
718 spin_lock(&cfile->file_info_lock);
719 if (!CIFS_CACHE_WRITE(cinode) &&
720 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
721 cfile->oplock_break_cancelled = true;
722 else
723 cfile->oplock_break_cancelled = false;
724
725 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
726 &cinode->flags);
727
728 cfile->oplock_epoch = 0;
729 cfile->oplock_level = rsp->OplockLevel;
730
731 spin_unlock(&cfile->file_info_lock);
732
733 cifs_queue_oplock_break(cfile);
734
735 spin_unlock(&tcon->open_file_lock);
736 spin_unlock(&cifs_tcp_ses_lock);
737 return true;
738 }
739 spin_unlock(&tcon->open_file_lock);
740 }
741 }
742 spin_unlock(&cifs_tcp_ses_lock);
743 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
744 trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
745 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
746 le64_to_cpu(rsp->hdr.SessionId));
747
748 return true;
749 }
750
751 void
752 smb2_cancelled_close_fid(struct work_struct *work)
753 {
754 struct close_cancelled_open *cancelled = container_of(work,
755 struct close_cancelled_open, work);
756 struct cifs_tcon *tcon = cancelled->tcon;
757 int rc;
758
759 if (cancelled->mid)
760 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
761 cancelled->mid);
762 else
763 cifs_tcon_dbg(VFS, "Close interrupted close\n");
764
765 rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
766 cancelled->fid.volatile_fid);
767 if (rc)
768 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
769
770 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close_fid);
771 kfree(cancelled);
772 }
773
774 /*
775 * Caller should already has an extra reference to @tcon
776 * This function is used to queue work to close a handle to prevent leaks
777 * on the server.
778 * We handle two cases. If an open was interrupted after we sent the
779 * SMB2_CREATE to the server but before we processed the reply, and second
780 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
781 */
782 static int
783 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
784 __u64 persistent_fid, __u64 volatile_fid)
785 {
786 struct close_cancelled_open *cancelled;
787
788 cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
789 if (!cancelled)
790 return -ENOMEM;
791
792 cancelled->fid.persistent_fid = persistent_fid;
793 cancelled->fid.volatile_fid = volatile_fid;
794 cancelled->tcon = tcon;
795 cancelled->cmd = cmd;
796 cancelled->mid = mid;
797 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
798 WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
799
800 return 0;
801 }
802
803 int
804 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
805 __u64 volatile_fid)
806 {
807 int rc;
808
809 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
810 spin_lock(&cifs_tcp_ses_lock);
811 if (tcon->tc_count <= 0) {
812 struct TCP_Server_Info *server = NULL;
813
814 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
815 netfs_trace_tcon_ref_see_cancelled_close);
816 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
817 spin_unlock(&cifs_tcp_ses_lock);
818
819 if (tcon->ses)
820 server = tcon->ses->server;
821
822 cifs_server_dbg(FYI, "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
823 tcon->tid, persistent_fid, volatile_fid);
824
825 return 0;
826 }
827 tcon->tc_count++;
828 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
829 netfs_trace_tcon_ref_get_cancelled_close);
830 spin_unlock(&cifs_tcp_ses_lock);
831
832 rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
833 persistent_fid, volatile_fid);
834 if (rc)
835 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close);
836
837 return rc;
838 }
839
840 int
841 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
842 {
843 struct smb2_hdr *hdr = mid->resp_buf;
844 struct smb2_create_rsp *rsp = mid->resp_buf;
845 struct cifs_tcon *tcon;
846 int rc;
847
848 if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
849 hdr->Status != STATUS_SUCCESS)
850 return 0;
851
852 tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
853 le32_to_cpu(hdr->Id.SyncId.TreeId));
854 if (!tcon)
855 return -ENOENT;
856
857 rc = __smb2_handle_cancelled_cmd(tcon,
858 le16_to_cpu(hdr->Command),
859 le64_to_cpu(hdr->MessageId),
860 rsp->PersistentFileId,
861 rsp->VolatileFileId);
862 if (rc)
863 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_mid);
864
865 return rc;
866 }
867
868 /**
869 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
870 *
871 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
872 * SMB2 header.
873 *
874 * @ses: server session structure
875 * @server: pointer to server info
876 * @iov: array containing the SMB request we will send to the server
877 * @nvec: number of array entries for the iov
878 */
879 int
880 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
881 struct kvec *iov, int nvec)
882 {
883 int i, rc;
884 struct smb2_hdr *hdr;
885 struct shash_desc *sha512 = NULL;
886
887 hdr = (struct smb2_hdr *)iov[0].iov_base;
888 /* neg prot are always taken */
889 if (hdr->Command == SMB2_NEGOTIATE)
890 goto ok;
891
892 /*
893 * If we process a command which wasn't a negprot it means the
894 * neg prot was already done, so the server dialect was set
895 * and we can test it. Preauth requires 3.1.1 for now.
896 */
897 if (server->dialect != SMB311_PROT_ID)
898 return 0;
899
900 if (hdr->Command != SMB2_SESSION_SETUP)
901 return 0;
902
903 /* skip last sess setup response */
904 if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
905 && (hdr->Status == NT_STATUS_OK
906 || (hdr->Status !=
907 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
908 return 0;
909
910 ok:
911 rc = smb311_crypto_shash_allocate(server);
912 if (rc)
913 return rc;
914
915 sha512 = server->secmech.sha512;
916 rc = crypto_shash_init(sha512);
917 if (rc) {
918 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
919 return rc;
920 }
921
922 rc = crypto_shash_update(sha512, ses->preauth_sha_hash,
923 SMB2_PREAUTH_HASH_SIZE);
924 if (rc) {
925 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
926 return rc;
927 }
928
929 for (i = 0; i < nvec; i++) {
930 rc = crypto_shash_update(sha512, iov[i].iov_base, iov[i].iov_len);
931 if (rc) {
932 cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
933 __func__);
934 return rc;
935 }
936 }
937
938 rc = crypto_shash_final(sha512, ses->preauth_sha_hash);
939 if (rc) {
940 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
941 __func__);
942 return rc;
943 }
944
945 return 0;
946 }
947
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