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 <crypto/sha2.h>
11 #include <linux/ctype.h>
12 #include "cifsglob.h"
13 #include "cifsproto.h"
14 #include "smb2proto.h"
15 #include "cifs_debug.h"
16 #include "cifs_unicode.h"
17 #include "../common/smb2status.h"
18 #include "smb2glob.h"
19 #include "nterr.h"
20 #include "cached_dir.h"
21
22 static int
check_smb2_hdr(struct smb2_hdr * shdr,__u64 mid)23 check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
24 {
25 __u64 wire_mid = le64_to_cpu(shdr->MessageId);
26
27 /*
28 * Make sure that this really is an SMB, that it is a response,
29 * and that the message ids match.
30 */
31 if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
32 (mid == wire_mid)) {
33 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
34 return 0;
35 else {
36 /* only one valid case where server sends us request */
37 if (shdr->Command == SMB2_OPLOCK_BREAK)
38 return 0;
39 else
40 cifs_dbg(VFS, "Received Request not response\n");
41 }
42 } else { /* bad signature or mid */
43 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
44 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
45 le32_to_cpu(shdr->ProtocolId));
46 if (mid != wire_mid)
47 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
48 mid, wire_mid);
49 }
50 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
51 return 1;
52 }
53
54 /*
55 * The following table defines the expected "StructureSize" of SMB2 responses
56 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
57 *
58 * Note that commands are defined in smb2pdu.h in le16 but the array below is
59 * indexed by command in host byte order
60 */
61 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
62 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
63 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
64 /* SMB2_LOGOFF */ cpu_to_le16(4),
65 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
66 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
67 /* SMB2_CREATE */ cpu_to_le16(89),
68 /* SMB2_CLOSE */ cpu_to_le16(60),
69 /* SMB2_FLUSH */ cpu_to_le16(4),
70 /* SMB2_READ */ cpu_to_le16(17),
71 /* SMB2_WRITE */ cpu_to_le16(17),
72 /* SMB2_LOCK */ cpu_to_le16(4),
73 /* SMB2_IOCTL */ cpu_to_le16(49),
74 /* BB CHECK this ... not listed in documentation */
75 /* SMB2_CANCEL */ cpu_to_le16(0),
76 /* SMB2_ECHO */ cpu_to_le16(4),
77 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
78 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
79 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
80 /* SMB2_SET_INFO */ cpu_to_le16(2),
81 /* BB FIXME can also be 44 for lease break */
82 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
83 };
84
85 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
86
get_neg_ctxt_len(struct smb2_hdr * hdr,__u32 len,__u32 non_ctxlen)87 static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
88 __u32 non_ctxlen)
89 {
90 __u16 neg_count;
91 __u32 nc_offset, size_of_pad_before_neg_ctxts;
92 struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
93
94 /* Negotiate contexts are only valid for latest dialect SMB3.11 */
95 neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
96 if ((neg_count == 0) ||
97 (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
98 return 0;
99
100 /*
101 * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
102 * which security mechanisms the server supports) make sure that
103 * the negotiate contexts start after it
104 */
105 nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
106 /*
107 * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
108 * and the latter is 1 byte bigger than the fix-sized area of the
109 * NEGOTIATE response
110 */
111 if (nc_offset + 1 < non_ctxlen) {
112 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
113 return 0;
114 } else if (nc_offset + 1 == non_ctxlen) {
115 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
116 size_of_pad_before_neg_ctxts = 0;
117 } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
118 /* has padding, but no SPNEGO blob */
119 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
120 else
121 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
122
123 /* Verify that at least minimal negotiate contexts fit within frame */
124 if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
125 pr_warn_once("negotiate context goes beyond end\n");
126 return 0;
127 }
128
129 cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
130 len - nc_offset, size_of_pad_before_neg_ctxts);
131
132 /* length of negcontexts including pad from end of sec blob to them */
133 return (len - nc_offset) + size_of_pad_before_neg_ctxts;
134 }
135
136 int
smb2_check_message(char * buf,unsigned int len,struct TCP_Server_Info * server)137 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
138 {
139 struct TCP_Server_Info *pserver;
140 struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
141 struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
142 int hdr_size = sizeof(struct smb2_hdr);
143 int pdu_size = sizeof(struct smb2_pdu);
144 int command;
145 __u32 calc_len; /* calculated length */
146 __u64 mid;
147
148 /* If server is a channel, select the primary channel */
149 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
150
151 /*
152 * Add function to do table lookup of StructureSize by command
153 * ie Validate the wct via smb2_struct_sizes table above
154 */
155 if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
156 struct smb2_transform_hdr *thdr =
157 (struct smb2_transform_hdr *)buf;
158 struct cifs_ses *ses = NULL;
159 struct cifs_ses *iter;
160
161 /* decrypt frame now that it is completely read in */
162 spin_lock(&cifs_tcp_ses_lock);
163 list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
164 if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
165 ses = iter;
166 break;
167 }
168 }
169 spin_unlock(&cifs_tcp_ses_lock);
170 if (!ses) {
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 (check_smb2_hdr(shdr, mid))
178 return 1;
179
180 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
181 cifs_dbg(VFS, "Invalid structure size %u\n",
182 le16_to_cpu(shdr->StructureSize));
183 return 1;
184 }
185
186 command = le16_to_cpu(shdr->Command);
187 if (command >= NUMBER_OF_SMB2_COMMANDS) {
188 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
189 return 1;
190 }
191
192 if (len < pdu_size) {
193 if ((len >= hdr_size)
194 && (shdr->Status != 0)) {
195 pdu->StructureSize2 = 0;
196 /*
197 * As with SMB/CIFS, on some error cases servers may
198 * not return wct properly
199 */
200 return 0;
201 } else {
202 cifs_dbg(VFS, "Length less than SMB header size\n");
203 }
204 return 1;
205 }
206 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
207 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
208 mid);
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_LE)) {
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 calc_len = smb2_calc_size(buf);
231
232 /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
233 * be 0, and not a real miscalculation */
234 if (command == SMB2_IOCTL_HE && calc_len == 0)
235 return 0;
236
237 if (command == SMB2_NEGOTIATE_HE)
238 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
239
240 if (len != calc_len) {
241 /* create failed on symlink */
242 if (command == SMB2_CREATE_HE &&
243 shdr->Status == STATUS_STOPPED_ON_SYMLINK)
244 return 0;
245 /* Windows 7 server returns 24 bytes more */
246 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
247 return 0;
248 /* server can return one byte more due to implied bcc[0] */
249 if (calc_len == len + 1)
250 return 0;
251
252 /*
253 * Some windows servers (win2016) will pad also the final
254 * PDU in a compound to 8 bytes.
255 */
256 if (ALIGN(calc_len, 8) == len)
257 return 0;
258
259 /*
260 * MacOS server pads after SMB2.1 write response with 3 bytes
261 * of junk. Other servers match RFC1001 len to actual
262 * SMB2/SMB3 frame length (header + smb2 response specific data)
263 * Some windows servers also pad up to 8 bytes when compounding.
264 */
265 if (calc_len < len)
266 return 0;
267
268 /* Only log a message if len was really miscalculated */
269 if (unlikely(cifsFYI))
270 cifs_dbg(FYI, "Server response too short: calculated "
271 "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
272 calc_len, len, command, mid);
273 else
274 pr_warn("Server response too short: calculated length "
275 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
276 calc_len, len, command, mid);
277
278 return 1;
279 }
280 return 0;
281 }
282
283 /*
284 * The size of the variable area depends on the offset and length fields
285 * located in different fields for various SMB2 responses. SMB2 responses
286 * with no variable length info, show an offset of zero for the offset field.
287 */
288 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
289 /* SMB2_NEGOTIATE */ true,
290 /* SMB2_SESSION_SETUP */ true,
291 /* SMB2_LOGOFF */ false,
292 /* SMB2_TREE_CONNECT */ false,
293 /* SMB2_TREE_DISCONNECT */ false,
294 /* SMB2_CREATE */ true,
295 /* SMB2_CLOSE */ false,
296 /* SMB2_FLUSH */ false,
297 /* SMB2_READ */ true,
298 /* SMB2_WRITE */ false,
299 /* SMB2_LOCK */ false,
300 /* SMB2_IOCTL */ true,
301 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
302 /* SMB2_ECHO */ false,
303 /* SMB2_QUERY_DIRECTORY */ true,
304 /* SMB2_CHANGE_NOTIFY */ true,
305 /* SMB2_QUERY_INFO */ true,
306 /* SMB2_SET_INFO */ false,
307 /* SMB2_OPLOCK_BREAK */ false
308 };
309
310 /*
311 * Returns the pointer to the beginning of the data area. Length of the data
312 * area and the offset to it (from the beginning of the smb are also returned.
313 */
314 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * shdr)315 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
316 {
317 const int max_off = 4096;
318 const int max_len = 128 * 1024;
319
320 *off = 0;
321 *len = 0;
322
323 /* error responses do not have data area */
324 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
325 (((struct smb2_err_rsp *)shdr)->StructureSize) ==
326 SMB2_ERROR_STRUCTURE_SIZE2_LE)
327 return NULL;
328
329 /*
330 * Following commands have data areas so we have to get the location
331 * of the data buffer offset and data buffer length for the particular
332 * command.
333 */
334 switch (shdr->Command) {
335 case SMB2_NEGOTIATE:
336 *off = le16_to_cpu(
337 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
338 *len = le16_to_cpu(
339 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
340 break;
341 case SMB2_SESSION_SETUP:
342 *off = le16_to_cpu(
343 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
344 *len = le16_to_cpu(
345 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
346 break;
347 case SMB2_CREATE:
348 *off = le32_to_cpu(
349 ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
350 *len = le32_to_cpu(
351 ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
352 break;
353 case SMB2_QUERY_INFO:
354 *off = le16_to_cpu(
355 ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
356 *len = le32_to_cpu(
357 ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
358 break;
359 case SMB2_READ:
360 /* TODO: is this a bug ? */
361 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
362 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
363 break;
364 case SMB2_QUERY_DIRECTORY:
365 *off = le16_to_cpu(
366 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
367 *len = le32_to_cpu(
368 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
369 break;
370 case SMB2_IOCTL:
371 *off = le32_to_cpu(
372 ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
373 *len = le32_to_cpu(
374 ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
375 break;
376 case SMB2_CHANGE_NOTIFY:
377 *off = le16_to_cpu(
378 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
379 *len = le32_to_cpu(
380 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
381 break;
382 default:
383 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
384 break;
385 }
386
387 /*
388 * Invalid length or offset probably means data area is invalid, but
389 * we have little choice but to ignore the data area in this case.
390 */
391 if (unlikely(*off < 0 || *off > max_off ||
392 *len < 0 || *len > max_len)) {
393 cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
394 __func__, *off, *len);
395 *off = 0;
396 *len = 0;
397 } else if (*off == 0) {
398 *len = 0;
399 }
400
401 /* return pointer to beginning of data area, ie offset from SMB start */
402 if (*off > 0 && *len > 0)
403 return (char *)shdr + *off;
404 return NULL;
405 }
406
407 /*
408 * Calculate the size of the SMB message based on the fixed header
409 * portion, the number of word parameters and the data portion of the message.
410 */
411 unsigned int
smb2_calc_size(void * buf)412 smb2_calc_size(void *buf)
413 {
414 struct smb2_pdu *pdu = buf;
415 struct smb2_hdr *shdr = &pdu->hdr;
416 int offset; /* the offset from the beginning of SMB to data area */
417 int data_length; /* the length of the variable length data area */
418 /* Structure Size has already been checked to make sure it is 64 */
419 int len = le16_to_cpu(shdr->StructureSize);
420
421 /*
422 * StructureSize2, ie length of fixed parameter area has already
423 * been checked to make sure it is the correct length.
424 */
425 len += le16_to_cpu(pdu->StructureSize2);
426
427 if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
428 goto calc_size_exit;
429
430 smb2_get_data_area_len(&offset, &data_length, shdr);
431 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
432
433 if (data_length > 0) {
434 /*
435 * Check to make sure that data area begins after fixed area,
436 * Note that last byte of the fixed area is part of data area
437 * for some commands, typically those with odd StructureSize,
438 * so we must add one to the calculation.
439 */
440 if (offset + 1 < len) {
441 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
442 offset + 1, len);
443 data_length = 0;
444 } else {
445 len = offset + data_length;
446 }
447 }
448 calc_size_exit:
449 cifs_dbg(FYI, "SMB2 len %d\n", len);
450 return len;
451 }
452
453 /* Note: caller must free return buffer */
454 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)455 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
456 {
457 int len;
458 const char *start_of_path;
459 __le16 *to;
460 int map_type;
461
462 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
463 map_type = SFM_MAP_UNI_RSVD;
464 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
465 map_type = SFU_MAP_UNI_RSVD;
466 else
467 map_type = NO_MAP_UNI_RSVD;
468
469 /* Windows doesn't allow paths beginning with \ */
470 if (from[0] == '\\')
471 start_of_path = from + 1;
472
473 /* SMB311 POSIX extensions paths do not include leading slash */
474 else if (cifs_sb_master_tlink(cifs_sb) &&
475 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
476 (from[0] == '/')) {
477 start_of_path = from + 1;
478 } else
479 start_of_path = from;
480
481 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
482 cifs_sb->local_nls, map_type);
483 return to;
484 }
485
486 __le32
smb2_get_lease_state(struct cifsInodeInfo * cinode)487 smb2_get_lease_state(struct cifsInodeInfo *cinode)
488 {
489 __le32 lease = 0;
490
491 if (CIFS_CACHE_WRITE(cinode))
492 lease |= SMB2_LEASE_WRITE_CACHING_LE;
493 if (CIFS_CACHE_HANDLE(cinode))
494 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
495 if (CIFS_CACHE_READ(cinode))
496 lease |= SMB2_LEASE_READ_CACHING_LE;
497 return lease;
498 }
499
500 struct smb2_lease_break_work {
501 struct work_struct lease_break;
502 struct tcon_link *tlink;
503 __u8 lease_key[16];
504 __le32 lease_state;
505 };
506
507 static void
cifs_ses_oplock_break(struct work_struct * work)508 cifs_ses_oplock_break(struct work_struct *work)
509 {
510 struct smb2_lease_break_work *lw = container_of(work,
511 struct smb2_lease_break_work, lease_break);
512 int rc = 0;
513
514 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
515 lw->lease_state);
516
517 cifs_dbg(FYI, "Lease release rc %d\n", rc);
518 cifs_put_tlink(lw->tlink);
519 kfree(lw);
520 }
521
522 static void
smb2_queue_pending_open_break(struct tcon_link * tlink,__u8 * lease_key,__le32 new_lease_state)523 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
524 __le32 new_lease_state)
525 {
526 struct smb2_lease_break_work *lw;
527
528 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
529 if (!lw) {
530 cifs_put_tlink(tlink);
531 return;
532 }
533
534 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
535 lw->tlink = tlink;
536 lw->lease_state = new_lease_state;
537 memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
538 queue_work(cifsiod_wq, &lw->lease_break);
539 }
540
541 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)542 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
543 {
544 __u8 lease_state;
545 struct cifsFileInfo *cfile;
546 struct cifsInodeInfo *cinode;
547 int ack_req = le32_to_cpu(rsp->Flags &
548 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
549
550 lease_state = le32_to_cpu(rsp->NewLeaseState);
551
552 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
553 cinode = CIFS_I(d_inode(cfile->dentry));
554
555 if (memcmp(cinode->lease_key, rsp->LeaseKey,
556 SMB2_LEASE_KEY_SIZE))
557 continue;
558
559 cifs_dbg(FYI, "found in the open list\n");
560 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
561 lease_state);
562
563 if (ack_req)
564 cfile->oplock_break_cancelled = false;
565 else
566 cfile->oplock_break_cancelled = true;
567
568 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
569
570 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
571 cfile->oplock_level = lease_state;
572
573 cifs_queue_oplock_break(cfile);
574 return true;
575 }
576
577 return false;
578 }
579
580 static struct cifs_pending_open *
smb2_tcon_find_pending_open_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)581 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
582 struct smb2_lease_break *rsp)
583 {
584 __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
585 int ack_req = le32_to_cpu(rsp->Flags &
586 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
587 struct cifs_pending_open *open;
588 struct cifs_pending_open *found = NULL;
589
590 list_for_each_entry(open, &tcon->pending_opens, olist) {
591 if (memcmp(open->lease_key, rsp->LeaseKey,
592 SMB2_LEASE_KEY_SIZE))
593 continue;
594
595 if (!found && ack_req) {
596 found = open;
597 }
598
599 cifs_dbg(FYI, "found in the pending open list\n");
600 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
601 lease_state);
602
603 open->oplock = lease_state;
604 }
605
606 return found;
607 }
608
609 static bool
smb2_is_valid_lease_break(char * buffer,struct TCP_Server_Info * server)610 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
611 {
612 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
613 struct TCP_Server_Info *pserver;
614 struct cifs_ses *ses;
615 struct cifs_tcon *tcon;
616 struct cifs_pending_open *open;
617
618 /* Trace receipt of lease break request from server */
619 trace_smb3_lease_break_enter(le32_to_cpu(rsp->CurrentLeaseState),
620 le32_to_cpu(rsp->Flags),
621 le16_to_cpu(rsp->Epoch),
622 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
623 le64_to_cpu(rsp->hdr.SessionId),
624 *((u64 *)rsp->LeaseKey),
625 *((u64 *)&rsp->LeaseKey[8]));
626
627 cifs_dbg(FYI, "Checking for lease break\n");
628
629 /* If server is a channel, select the primary channel */
630 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
631
632 /* look up tcon based on tid & uid */
633 spin_lock(&cifs_tcp_ses_lock);
634 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
635 if (cifs_ses_exiting(ses))
636 continue;
637 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
638 spin_lock(&tcon->open_file_lock);
639 cifs_stats_inc(
640 &tcon->stats.cifs_stats.num_oplock_brks);
641 if (smb2_tcon_has_lease(tcon, rsp)) {
642 spin_unlock(&tcon->open_file_lock);
643 spin_unlock(&cifs_tcp_ses_lock);
644 return true;
645 }
646 open = smb2_tcon_find_pending_open_lease(tcon,
647 rsp);
648 if (open) {
649 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
650 struct tcon_link *tlink;
651
652 tlink = cifs_get_tlink(open->tlink);
653 memcpy(lease_key, open->lease_key,
654 SMB2_LEASE_KEY_SIZE);
655 spin_unlock(&tcon->open_file_lock);
656 spin_unlock(&cifs_tcp_ses_lock);
657 smb2_queue_pending_open_break(tlink,
658 lease_key,
659 rsp->NewLeaseState);
660 return true;
661 }
662 spin_unlock(&tcon->open_file_lock);
663
664 if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
665 spin_unlock(&cifs_tcp_ses_lock);
666 return true;
667 }
668 }
669 }
670 spin_unlock(&cifs_tcp_ses_lock);
671 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
672 trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
673 le32_to_cpu(rsp->Flags),
674 le16_to_cpu(rsp->Epoch),
675 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
676 le64_to_cpu(rsp->hdr.SessionId),
677 *((u64 *)rsp->LeaseKey),
678 *((u64 *)&rsp->LeaseKey[8]));
679
680 return false;
681 }
682
683 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)684 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
685 {
686 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
687 struct TCP_Server_Info *pserver;
688 struct cifs_ses *ses;
689 struct cifs_tcon *tcon;
690 struct cifsInodeInfo *cinode;
691 struct cifsFileInfo *cfile;
692
693 cifs_dbg(FYI, "Checking for oplock break\n");
694
695 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
696 return false;
697
698 if (rsp->StructureSize !=
699 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
700 if (le16_to_cpu(rsp->StructureSize) == 44)
701 return smb2_is_valid_lease_break(buffer, server);
702 else
703 return false;
704 }
705
706 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
707
708 /* If server is a channel, select the primary channel */
709 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
710
711 /* look up tcon based on tid & uid */
712 spin_lock(&cifs_tcp_ses_lock);
713 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
714 if (cifs_ses_exiting(ses))
715 continue;
716 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
717
718 spin_lock(&tcon->open_file_lock);
719 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
720 if (rsp->PersistentFid !=
721 cfile->fid.persistent_fid ||
722 rsp->VolatileFid !=
723 cfile->fid.volatile_fid)
724 continue;
725
726 cifs_dbg(FYI, "file id match, oplock break\n");
727 cifs_stats_inc(
728 &tcon->stats.cifs_stats.num_oplock_brks);
729 cinode = CIFS_I(d_inode(cfile->dentry));
730 spin_lock(&cfile->file_info_lock);
731 if (!CIFS_CACHE_WRITE(cinode) &&
732 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
733 cfile->oplock_break_cancelled = true;
734 else
735 cfile->oplock_break_cancelled = false;
736
737 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
738 &cinode->flags);
739
740 cfile->oplock_epoch = 0;
741 cfile->oplock_level = rsp->OplockLevel;
742
743 spin_unlock(&cfile->file_info_lock);
744
745 cifs_queue_oplock_break(cfile);
746
747 spin_unlock(&tcon->open_file_lock);
748 spin_unlock(&cifs_tcp_ses_lock);
749 return true;
750 }
751 spin_unlock(&tcon->open_file_lock);
752 }
753 }
754 spin_unlock(&cifs_tcp_ses_lock);
755 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
756 trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
757 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
758 le64_to_cpu(rsp->hdr.SessionId));
759
760 return true;
761 }
762
763 void
smb2_cancelled_close_fid(struct work_struct * work)764 smb2_cancelled_close_fid(struct work_struct *work)
765 {
766 struct close_cancelled_open *cancelled = container_of(work,
767 struct close_cancelled_open, work);
768 struct cifs_tcon *tcon = cancelled->tcon;
769 int rc;
770
771 if (cancelled->mid)
772 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
773 cancelled->mid);
774 else
775 cifs_tcon_dbg(VFS, "Close interrupted close\n");
776
777 rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
778 cancelled->fid.volatile_fid);
779 if (rc)
780 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
781
782 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close_fid);
783 kfree(cancelled);
784 }
785
786 /*
787 * Caller should already has an extra reference to @tcon
788 * This function is used to queue work to close a handle to prevent leaks
789 * on the server.
790 * We handle two cases. If an open was interrupted after we sent the
791 * SMB2_CREATE to the server but before we processed the reply, and second
792 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
793 */
794 static int
__smb2_handle_cancelled_cmd(struct cifs_tcon * tcon,__u16 cmd,__u64 mid,__u64 persistent_fid,__u64 volatile_fid)795 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
796 __u64 persistent_fid, __u64 volatile_fid)
797 {
798 struct close_cancelled_open *cancelled;
799
800 cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
801 if (!cancelled)
802 return -ENOMEM;
803
804 cancelled->fid.persistent_fid = persistent_fid;
805 cancelled->fid.volatile_fid = volatile_fid;
806 cancelled->tcon = tcon;
807 cancelled->cmd = cmd;
808 cancelled->mid = mid;
809 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
810 WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
811
812 return 0;
813 }
814
815 int
smb2_handle_cancelled_close(struct cifs_tcon * tcon,__u64 persistent_fid,__u64 volatile_fid)816 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
817 __u64 volatile_fid)
818 {
819 int rc;
820
821 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
822 spin_lock(&cifs_tcp_ses_lock);
823 if (tcon->tc_count <= 0) {
824 struct TCP_Server_Info *server = NULL;
825
826 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
827 netfs_trace_tcon_ref_see_cancelled_close);
828 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
829 spin_unlock(&cifs_tcp_ses_lock);
830
831 if (tcon->ses) {
832 server = tcon->ses->server;
833 cifs_server_dbg(FYI,
834 "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
835 tcon->tid, persistent_fid, volatile_fid);
836 }
837
838 return 0;
839 }
840 tcon->tc_count++;
841 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
842 netfs_trace_tcon_ref_get_cancelled_close);
843 spin_unlock(&cifs_tcp_ses_lock);
844
845 rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
846 persistent_fid, volatile_fid);
847 if (rc)
848 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close);
849
850 return rc;
851 }
852
853 int
smb2_handle_cancelled_mid(struct mid_q_entry * mid,struct TCP_Server_Info * server)854 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
855 {
856 struct smb2_hdr *hdr = mid->resp_buf;
857 struct smb2_create_rsp *rsp = mid->resp_buf;
858 struct cifs_tcon *tcon;
859 int rc;
860
861 if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
862 hdr->Status != STATUS_SUCCESS)
863 return 0;
864
865 tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
866 le32_to_cpu(hdr->Id.SyncId.TreeId));
867 if (!tcon)
868 return -ENOENT;
869
870 rc = __smb2_handle_cancelled_cmd(tcon,
871 le16_to_cpu(hdr->Command),
872 le64_to_cpu(hdr->MessageId),
873 rsp->PersistentFileId,
874 rsp->VolatileFileId);
875 if (rc)
876 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_mid);
877
878 return rc;
879 }
880
881 /**
882 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
883 *
884 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
885 * SMB2 header.
886 *
887 * @ses: server session structure
888 * @server: pointer to server info
889 * @iov: array containing the SMB request we will send to the server
890 * @nvec: number of array entries for the iov
891 */
892 void
smb311_update_preauth_hash(struct cifs_ses * ses,struct TCP_Server_Info * server,struct kvec * iov,int nvec)893 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
894 struct kvec *iov, int nvec)
895 {
896 int i;
897 struct smb2_hdr *hdr;
898 struct sha512_ctx sha_ctx;
899
900 hdr = (struct smb2_hdr *)iov[0].iov_base;
901 /* neg prot are always taken */
902 if (hdr->Command == SMB2_NEGOTIATE)
903 goto ok;
904
905 /*
906 * If we process a command which wasn't a negprot it means the
907 * neg prot was already done, so the server dialect was set
908 * and we can test it. Preauth requires 3.1.1 for now.
909 */
910 if (server->dialect != SMB311_PROT_ID)
911 return;
912
913 if (hdr->Command != SMB2_SESSION_SETUP)
914 return;
915
916 /* skip last sess setup response */
917 if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
918 && (hdr->Status == NT_STATUS_OK
919 || (hdr->Status !=
920 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
921 return;
922
923 ok:
924 sha512_init(&sha_ctx);
925 sha512_update(&sha_ctx, ses->preauth_sha_hash, SMB2_PREAUTH_HASH_SIZE);
926 for (i = 0; i < nvec; i++)
927 sha512_update(&sha_ctx, iov[i].iov_base, iov[i].iov_len);
928 sha512_final(&sha_ctx, ses->preauth_sha_hash);
929 }
930