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 pdu_len,unsigned int len,struct TCP_Server_Info * server)137 smb2_check_message(char *buf, unsigned int pdu_len, unsigned int len,
138 struct TCP_Server_Info *server)
139 {
140 struct TCP_Server_Info *pserver;
141 struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
142 struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
143 int hdr_size = sizeof(struct smb2_hdr);
144 int pdu_size = sizeof(struct smb2_pdu);
145 int command;
146 __u32 calc_len; /* calculated length */
147 __u64 mid;
148
149 /* If server is a channel, select the primary channel */
150 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
151
152 /*
153 * Add function to do table lookup of StructureSize by command
154 * ie Validate the wct via smb2_struct_sizes table above
155 */
156 if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
157 struct smb2_transform_hdr *thdr =
158 (struct smb2_transform_hdr *)buf;
159 struct cifs_ses *ses = NULL;
160 struct cifs_ses *iter;
161
162 /* decrypt frame now that it is completely read in */
163 spin_lock(&cifs_tcp_ses_lock);
164 list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
165 if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
166 ses = iter;
167 break;
168 }
169 }
170 spin_unlock(&cifs_tcp_ses_lock);
171 if (!ses) {
172 cifs_dbg(VFS, "no decryption - session id not found\n");
173 return 1;
174 }
175 }
176
177 mid = le64_to_cpu(shdr->MessageId);
178 if (check_smb2_hdr(shdr, mid))
179 return 1;
180
181 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
182 cifs_dbg(VFS, "Invalid structure size %u\n",
183 le16_to_cpu(shdr->StructureSize));
184 return 1;
185 }
186
187 command = le16_to_cpu(shdr->Command);
188 if (command >= NUMBER_OF_SMB2_COMMANDS) {
189 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
190 return 1;
191 }
192
193 if (len < pdu_size) {
194 if ((len >= hdr_size)
195 && (shdr->Status != 0)) {
196 pdu->StructureSize2 = 0;
197 /*
198 * As with SMB/CIFS, on some error cases servers may
199 * not return wct properly
200 */
201 return 0;
202 } else {
203 cifs_dbg(VFS, "Length less than SMB header size\n");
204 }
205 return 1;
206 }
207 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
208 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
209 mid);
210 return 1;
211 }
212
213 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
214 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
215 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
216 /* error packets have 9 byte structure size */
217 cifs_dbg(VFS, "Invalid response size %u for command %d\n",
218 le16_to_cpu(pdu->StructureSize2), command);
219 return 1;
220 } else if (command == SMB2_OPLOCK_BREAK_HE
221 && (shdr->Status == 0)
222 && (le16_to_cpu(pdu->StructureSize2) != 44)
223 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
224 /* special case for SMB2.1 lease break message */
225 cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
226 le16_to_cpu(pdu->StructureSize2));
227 return 1;
228 }
229 }
230
231 calc_len = smb2_calc_size(buf);
232
233 /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
234 * be 0, and not a real miscalculation */
235 if (command == SMB2_IOCTL_HE && calc_len == 0)
236 return 0;
237
238 if (command == SMB2_NEGOTIATE_HE)
239 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
240
241 if (len != calc_len) {
242 /* create failed on symlink */
243 if (command == SMB2_CREATE_HE &&
244 shdr->Status == STATUS_STOPPED_ON_SYMLINK)
245 return 0;
246 /* Windows 7 server returns 24 bytes more */
247 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
248 return 0;
249 /* server can return one byte more due to implied bcc[0] */
250 if (calc_len == len + 1)
251 return 0;
252
253 /*
254 * Some windows servers (win2016) will pad also the final
255 * PDU in a compound to 8 bytes.
256 */
257 if (ALIGN(calc_len, 8) == len)
258 return 0;
259
260 /*
261 * MacOS server pads after SMB2.1 write response with 3 bytes
262 * of junk. Other servers match RFC1001 len to actual
263 * SMB2/SMB3 frame length (header + smb2 response specific data)
264 * Some windows servers also pad up to 8 bytes when compounding.
265 */
266 if (calc_len < len)
267 return 0;
268
269 /* Only log a message if len was really miscalculated */
270 if (unlikely(cifsFYI))
271 cifs_dbg(FYI, "Server response too short: calculated "
272 "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
273 calc_len, len, command, mid);
274 else
275 pr_warn("Server response too short: calculated length "
276 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
277 calc_len, len, command, mid);
278
279 return 1;
280 }
281 return 0;
282 }
283
284 /*
285 * The size of the variable area depends on the offset and length fields
286 * located in different fields for various SMB2 responses. SMB2 responses
287 * with no variable length info, show an offset of zero for the offset field.
288 */
289 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
290 /* SMB2_NEGOTIATE */ true,
291 /* SMB2_SESSION_SETUP */ true,
292 /* SMB2_LOGOFF */ false,
293 /* SMB2_TREE_CONNECT */ false,
294 /* SMB2_TREE_DISCONNECT */ false,
295 /* SMB2_CREATE */ true,
296 /* SMB2_CLOSE */ false,
297 /* SMB2_FLUSH */ false,
298 /* SMB2_READ */ true,
299 /* SMB2_WRITE */ false,
300 /* SMB2_LOCK */ false,
301 /* SMB2_IOCTL */ true,
302 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
303 /* SMB2_ECHO */ false,
304 /* SMB2_QUERY_DIRECTORY */ true,
305 /* SMB2_CHANGE_NOTIFY */ true,
306 /* SMB2_QUERY_INFO */ true,
307 /* SMB2_SET_INFO */ false,
308 /* SMB2_OPLOCK_BREAK */ false
309 };
310
311 /*
312 * Returns the pointer to the beginning of the data area. Length of the data
313 * area and the offset to it (from the beginning of the smb are also returned.
314 */
315 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * shdr)316 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
317 {
318 const int max_off = 4096;
319 const int max_len = 128 * 1024;
320
321 *off = 0;
322 *len = 0;
323
324 /* error responses do not have data area */
325 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
326 (((struct smb2_err_rsp *)shdr)->StructureSize) ==
327 SMB2_ERROR_STRUCTURE_SIZE2_LE)
328 return NULL;
329
330 /*
331 * Following commands have data areas so we have to get the location
332 * of the data buffer offset and data buffer length for the particular
333 * command.
334 */
335 switch (shdr->Command) {
336 case SMB2_NEGOTIATE:
337 *off = le16_to_cpu(
338 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
339 *len = le16_to_cpu(
340 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
341 break;
342 case SMB2_SESSION_SETUP:
343 *off = le16_to_cpu(
344 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
345 *len = le16_to_cpu(
346 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
347 break;
348 case SMB2_CREATE:
349 *off = le32_to_cpu(
350 ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
351 *len = le32_to_cpu(
352 ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
353 break;
354 case SMB2_QUERY_INFO:
355 *off = le16_to_cpu(
356 ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
357 *len = le32_to_cpu(
358 ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
359 break;
360 case SMB2_READ:
361 /* TODO: is this a bug ? */
362 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
363 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
364 break;
365 case SMB2_QUERY_DIRECTORY:
366 *off = le16_to_cpu(
367 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
368 *len = le32_to_cpu(
369 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
370 break;
371 case SMB2_IOCTL:
372 *off = le32_to_cpu(
373 ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
374 *len = le32_to_cpu(
375 ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
376 break;
377 case SMB2_CHANGE_NOTIFY:
378 *off = le16_to_cpu(
379 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
380 *len = le32_to_cpu(
381 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
382 break;
383 default:
384 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
385 break;
386 }
387
388 /*
389 * Invalid length or offset probably means data area is invalid, but
390 * we have little choice but to ignore the data area in this case.
391 */
392 if (unlikely(*off < 0 || *off > max_off ||
393 *len < 0 || *len > max_len)) {
394 cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
395 __func__, *off, *len);
396 *off = 0;
397 *len = 0;
398 } else if (*off == 0) {
399 *len = 0;
400 }
401
402 /* return pointer to beginning of data area, ie offset from SMB start */
403 if (*off > 0 && *len > 0)
404 return (char *)shdr + *off;
405 return NULL;
406 }
407
408 /*
409 * Calculate the size of the SMB message based on the fixed header
410 * portion, the number of word parameters and the data portion of the message.
411 */
412 unsigned int
smb2_calc_size(void * buf)413 smb2_calc_size(void *buf)
414 {
415 struct smb2_pdu *pdu = buf;
416 struct smb2_hdr *shdr = &pdu->hdr;
417 int offset; /* the offset from the beginning of SMB to data area */
418 int data_length; /* the length of the variable length data area */
419 /* Structure Size has already been checked to make sure it is 64 */
420 int len = le16_to_cpu(shdr->StructureSize);
421
422 /*
423 * StructureSize2, ie length of fixed parameter area has already
424 * been checked to make sure it is the correct length.
425 */
426 len += le16_to_cpu(pdu->StructureSize2);
427
428 if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
429 goto calc_size_exit;
430
431 smb2_get_data_area_len(&offset, &data_length, shdr);
432 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
433
434 if (data_length > 0) {
435 /*
436 * Check to make sure that data area begins after fixed area,
437 * Note that last byte of the fixed area is part of data area
438 * for some commands, typically those with odd StructureSize,
439 * so we must add one to the calculation.
440 */
441 if (offset + 1 < len) {
442 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
443 offset + 1, len);
444 data_length = 0;
445 } else {
446 len = offset + data_length;
447 }
448 }
449 calc_size_exit:
450 cifs_dbg(FYI, "SMB2 len %d\n", len);
451 return len;
452 }
453
454 /* Note: caller must free return buffer */
455 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)456 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
457 {
458 const char *start_of_path;
459 int len;
460
461 /* Windows doesn't allow paths beginning with \ */
462 if (from[0] == '\\')
463 start_of_path = from + 1;
464
465 /* SMB311 POSIX extensions paths do not include leading slash */
466 else if (cifs_sb_master_tlink(cifs_sb) &&
467 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
468 (from[0] == '/')) {
469 start_of_path = from + 1;
470 } else
471 start_of_path = from;
472
473 return cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
474 cifs_sb->local_nls, cifs_remap(cifs_sb));
475 }
476
smb2_get_lease_state(struct cifsInodeInfo * cinode,unsigned int oplock)477 __le32 smb2_get_lease_state(struct cifsInodeInfo *cinode, unsigned int oplock)
478 {
479 unsigned int sbflags = cifs_sb_flags(CIFS_SB(cinode));
480 __le32 lease = 0;
481
482 if ((oplock & CIFS_CACHE_WRITE_FLG) || (sbflags & CIFS_MOUNT_RW_CACHE))
483 lease |= SMB2_LEASE_WRITE_CACHING_LE;
484 if (oplock & CIFS_CACHE_HANDLE_FLG)
485 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
486 if ((oplock & CIFS_CACHE_READ_FLG) || (sbflags & CIFS_MOUNT_RO_CACHE))
487 lease |= SMB2_LEASE_READ_CACHING_LE;
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_obj(struct smb2_lease_break_work);
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 cifsFileInfo *cfile;
537 struct cifsInodeInfo *cinode;
538 int ack_req = le32_to_cpu(rsp->Flags &
539 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
540
541 lease_state = le32_to_cpu(rsp->NewLeaseState);
542
543 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
544 cinode = CIFS_I(d_inode(cfile->dentry));
545
546 if (memcmp(cinode->lease_key, rsp->LeaseKey,
547 SMB2_LEASE_KEY_SIZE))
548 continue;
549
550 cifs_dbg(FYI, "found in the open list\n");
551 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
552 lease_state);
553
554 if (ack_req)
555 cfile->oplock_break_cancelled = false;
556 else
557 cfile->oplock_break_cancelled = true;
558
559 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
560
561 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
562 cfile->oplock_level = lease_state;
563
564 cifs_queue_oplock_break(cfile);
565 return true;
566 }
567
568 return false;
569 }
570
571 static struct cifs_pending_open *
smb2_tcon_find_pending_open_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)572 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
573 struct smb2_lease_break *rsp)
574 {
575 __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
576 int ack_req = le32_to_cpu(rsp->Flags &
577 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
578 struct cifs_pending_open *open;
579 struct cifs_pending_open *found = NULL;
580
581 list_for_each_entry(open, &tcon->pending_opens, olist) {
582 if (memcmp(open->lease_key, rsp->LeaseKey,
583 SMB2_LEASE_KEY_SIZE))
584 continue;
585
586 if (!found && ack_req) {
587 found = open;
588 }
589
590 cifs_dbg(FYI, "found in the pending open list\n");
591 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
592 lease_state);
593
594 open->oplock = lease_state;
595 }
596
597 return found;
598 }
599
600 static bool
smb2_is_valid_lease_break(char * buffer,struct TCP_Server_Info * server)601 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
602 {
603 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
604 struct TCP_Server_Info *pserver;
605 struct cifs_ses *ses;
606 struct cifs_tcon *tcon;
607 struct cifs_pending_open *open;
608
609 /* Trace receipt of lease break request from server */
610 trace_smb3_lease_break_enter(le32_to_cpu(rsp->CurrentLeaseState),
611 le32_to_cpu(rsp->Flags),
612 le16_to_cpu(rsp->Epoch),
613 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
614 le64_to_cpu(rsp->hdr.SessionId),
615 *((u64 *)rsp->LeaseKey),
616 *((u64 *)&rsp->LeaseKey[8]));
617
618 cifs_dbg(FYI, "Checking for lease break\n");
619
620 /* If server is a channel, select the primary channel */
621 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
622
623 /* look up tcon based on tid & uid */
624 spin_lock(&cifs_tcp_ses_lock);
625 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
626 if (cifs_ses_exiting(ses))
627 continue;
628 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
629 spin_lock(&tcon->open_file_lock);
630 cifs_stats_inc(
631 &tcon->stats.cifs_stats.num_oplock_brks);
632 if (smb2_tcon_has_lease(tcon, rsp)) {
633 spin_unlock(&tcon->open_file_lock);
634 spin_unlock(&cifs_tcp_ses_lock);
635 return true;
636 }
637 open = smb2_tcon_find_pending_open_lease(tcon,
638 rsp);
639 if (open) {
640 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
641 struct tcon_link *tlink;
642
643 tlink = cifs_get_tlink(open->tlink);
644 memcpy(lease_key, open->lease_key,
645 SMB2_LEASE_KEY_SIZE);
646 spin_unlock(&tcon->open_file_lock);
647 spin_unlock(&cifs_tcp_ses_lock);
648 smb2_queue_pending_open_break(tlink,
649 lease_key,
650 rsp->NewLeaseState);
651 return true;
652 }
653 spin_unlock(&tcon->open_file_lock);
654
655 if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
656 spin_unlock(&cifs_tcp_ses_lock);
657 return true;
658 }
659 }
660 }
661 spin_unlock(&cifs_tcp_ses_lock);
662 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
663 trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
664 le32_to_cpu(rsp->Flags),
665 le16_to_cpu(rsp->Epoch),
666 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
667 le64_to_cpu(rsp->hdr.SessionId),
668 *((u64 *)rsp->LeaseKey),
669 *((u64 *)&rsp->LeaseKey[8]));
670
671 return false;
672 }
673
674 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)675 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
676 {
677 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
678 struct TCP_Server_Info *pserver;
679 struct cifs_ses *ses;
680 struct cifs_tcon *tcon;
681 struct cifsInodeInfo *cinode;
682 struct cifsFileInfo *cfile;
683
684 cifs_dbg(FYI, "Checking for oplock break\n");
685
686 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
687 return false;
688
689 if (rsp->StructureSize !=
690 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
691 if (le16_to_cpu(rsp->StructureSize) == 44)
692 return smb2_is_valid_lease_break(buffer, server);
693 else
694 return false;
695 }
696
697 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
698
699 /* If server is a channel, select the primary channel */
700 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
701
702 /* look up tcon based on tid & uid */
703 spin_lock(&cifs_tcp_ses_lock);
704 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
705 if (cifs_ses_exiting(ses))
706 continue;
707 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
708
709 spin_lock(&tcon->open_file_lock);
710 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
711 if (rsp->PersistentFid !=
712 cfile->fid.persistent_fid ||
713 rsp->VolatileFid !=
714 cfile->fid.volatile_fid)
715 continue;
716
717 cifs_dbg(FYI, "file id match, oplock break\n");
718 cifs_stats_inc(
719 &tcon->stats.cifs_stats.num_oplock_brks);
720 cinode = CIFS_I(d_inode(cfile->dentry));
721 spin_lock(&cfile->file_info_lock);
722 if (!CIFS_CACHE_WRITE(cinode) &&
723 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
724 cfile->oplock_break_cancelled = true;
725 else
726 cfile->oplock_break_cancelled = false;
727
728 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
729 &cinode->flags);
730
731 cfile->oplock_epoch = 0;
732 cfile->oplock_level = rsp->OplockLevel;
733
734 spin_unlock(&cfile->file_info_lock);
735
736 cifs_queue_oplock_break(cfile);
737
738 spin_unlock(&tcon->open_file_lock);
739 spin_unlock(&cifs_tcp_ses_lock);
740 return true;
741 }
742 spin_unlock(&tcon->open_file_lock);
743 }
744 }
745 spin_unlock(&cifs_tcp_ses_lock);
746 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
747 trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
748 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
749 le64_to_cpu(rsp->hdr.SessionId));
750
751 return true;
752 }
753
754 void
smb2_cancelled_close_fid(struct work_struct * work)755 smb2_cancelled_close_fid(struct work_struct *work)
756 {
757 struct close_cancelled_open *cancelled = container_of(work,
758 struct close_cancelled_open, work);
759 struct cifs_tcon *tcon = cancelled->tcon;
760 int rc;
761
762 if (cancelled->mid)
763 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
764 cancelled->mid);
765 else
766 cifs_tcon_dbg(VFS, "Close interrupted close\n");
767
768 rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
769 cancelled->fid.volatile_fid);
770 if (rc)
771 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
772
773 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close_fid);
774 kfree(cancelled);
775 }
776
777 /*
778 * Caller should already has an extra reference to @tcon
779 * This function is used to queue work to close a handle to prevent leaks
780 * on the server.
781 * We handle two cases. If an open was interrupted after we sent the
782 * SMB2_CREATE to the server but before we processed the reply, and second
783 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
784 */
785 static int
__smb2_handle_cancelled_cmd(struct cifs_tcon * tcon,__u16 cmd,__u64 mid,__u64 persistent_fid,__u64 volatile_fid)786 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
787 __u64 persistent_fid, __u64 volatile_fid)
788 {
789 struct close_cancelled_open *cancelled;
790
791 cancelled = kzalloc_obj(*cancelled);
792 if (!cancelled)
793 return -ENOMEM;
794
795 cancelled->fid.persistent_fid = persistent_fid;
796 cancelled->fid.volatile_fid = volatile_fid;
797 cancelled->tcon = tcon;
798 cancelled->cmd = cmd;
799 cancelled->mid = mid;
800 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
801 WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
802
803 return 0;
804 }
805
806 int
smb2_handle_cancelled_close(struct cifs_tcon * tcon,__u64 persistent_fid,__u64 volatile_fid)807 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
808 __u64 volatile_fid)
809 {
810 int rc;
811
812 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
813 spin_lock(&tcon->tc_lock);
814 if (tcon->tc_count <= 0) {
815 struct TCP_Server_Info *server = NULL;
816
817 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
818 netfs_trace_tcon_ref_see_cancelled_close);
819 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
820 spin_unlock(&tcon->tc_lock);
821
822 if (tcon->ses) {
823 server = tcon->ses->server;
824 cifs_server_dbg(FYI,
825 "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
826 tcon->tid, persistent_fid, volatile_fid);
827 }
828
829 return 0;
830 }
831 tcon->tc_count++;
832 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
833 netfs_trace_tcon_ref_get_cancelled_close);
834 spin_unlock(&tcon->tc_lock);
835
836 rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
837 persistent_fid, volatile_fid);
838 if (rc)
839 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close);
840
841 return rc;
842 }
843
844 int
smb2_handle_cancelled_mid(struct mid_q_entry * mid,struct TCP_Server_Info * server)845 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
846 {
847 struct smb2_hdr *hdr = mid->resp_buf;
848 struct smb2_create_rsp *rsp = mid->resp_buf;
849 struct cifs_tcon *tcon;
850 int rc;
851
852 if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
853 hdr->Status != STATUS_SUCCESS)
854 return 0;
855
856 tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
857 le32_to_cpu(hdr->Id.SyncId.TreeId));
858 if (!tcon)
859 return -ENOENT;
860
861 rc = __smb2_handle_cancelled_cmd(tcon,
862 le16_to_cpu(hdr->Command),
863 le64_to_cpu(hdr->MessageId),
864 rsp->PersistentFileId,
865 rsp->VolatileFileId);
866 if (rc)
867 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_mid);
868
869 return rc;
870 }
871
872 /**
873 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
874 *
875 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
876 * SMB2 header.
877 *
878 * @ses: server session structure
879 * @server: pointer to server info
880 * @iov: array containing the SMB request we will send to the server
881 * @nvec: number of array entries for the iov
882 */
883 void
smb311_update_preauth_hash(struct cifs_ses * ses,struct TCP_Server_Info * server,struct kvec * iov,int nvec)884 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
885 struct kvec *iov, int nvec)
886 {
887 int i;
888 struct smb2_hdr *hdr;
889 struct sha512_ctx sha_ctx;
890
891 hdr = (struct smb2_hdr *)iov[0].iov_base;
892 /* neg prot are always taken */
893 if (hdr->Command == SMB2_NEGOTIATE)
894 goto ok;
895
896 /*
897 * If we process a command which wasn't a negprot it means the
898 * neg prot was already done, so the server dialect was set
899 * and we can test it. Preauth requires 3.1.1 for now.
900 */
901 if (server->dialect != SMB311_PROT_ID)
902 return;
903
904 if (hdr->Command != SMB2_SESSION_SETUP)
905 return;
906
907 /* skip last sess setup response */
908 if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
909 && (hdr->Status == NT_STATUS_OK
910 || (hdr->Status !=
911 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
912 return;
913
914 ok:
915 sha512_init(&sha_ctx);
916 sha512_update(&sha_ctx, ses->preauth_sha_hash, SMB2_PREAUTH_HASH_SIZE);
917 for (i = 0; i < nvec; i++)
918 sha512_update(&sha_ctx, iov[i].iov_base, iov[i].iov_len);
919 sha512_final(&sha_ctx, ses->preauth_sha_hash);
920 }
921