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 unsigned int __smb2_calc_size(void *buf, bool *have_data,
23 bool *data_area_overlap);
24
25 static int
check_smb2_hdr(struct smb2_hdr * shdr,__u64 mid)26 check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
27 {
28 __u64 wire_mid = le64_to_cpu(shdr->MessageId);
29
30 /*
31 * Make sure that this really is an SMB, that it is a response,
32 * and that the message ids match.
33 */
34 if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
35 (mid == wire_mid)) {
36 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
37 return 0;
38 else {
39 /* only one valid case where server sends us request */
40 if (shdr->Command == SMB2_OPLOCK_BREAK)
41 return 0;
42 else
43 cifs_dbg(VFS, "Received Request not response\n");
44 }
45 } else { /* bad signature or mid */
46 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
47 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
48 le32_to_cpu(shdr->ProtocolId));
49 if (mid != wire_mid)
50 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
51 mid, wire_mid);
52 }
53 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
54 return 1;
55 }
56
57 /*
58 * The following table defines the expected "StructureSize" of SMB2 responses
59 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
60 *
61 * Note that commands are defined in smb2pdu.h in le16 but the array below is
62 * indexed by command in host byte order
63 */
64 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
65 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
66 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
67 /* SMB2_LOGOFF */ cpu_to_le16(4),
68 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
69 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
70 /* SMB2_CREATE */ cpu_to_le16(89),
71 /* SMB2_CLOSE */ cpu_to_le16(60),
72 /* SMB2_FLUSH */ cpu_to_le16(4),
73 /* SMB2_READ */ cpu_to_le16(17),
74 /* SMB2_WRITE */ cpu_to_le16(17),
75 /* SMB2_LOCK */ cpu_to_le16(4),
76 /* SMB2_IOCTL */ cpu_to_le16(49),
77 /* BB CHECK this ... not listed in documentation */
78 /* SMB2_CANCEL */ cpu_to_le16(0),
79 /* SMB2_ECHO */ cpu_to_le16(4),
80 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
81 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
82 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
83 /* SMB2_SET_INFO */ cpu_to_le16(2),
84 /* BB FIXME can also be 44 for lease break */
85 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
86 };
87
88 /*
89 * Minimum received PDU size for commands whose response carries a
90 * variable-length data area. A non-zero entry marks the command as
91 * having one, and gives the length smb2_check_message() requires
92 * before smb2_get_data_area_len() reads the offset and length fields
93 * out of the fixed response struct.
94 */
95 static const size_t smb2_min_pdu_len[NUMBER_OF_SMB2_COMMANDS] = {
96 /* SMB2_NEGOTIATE */ sizeof(struct smb2_negotiate_rsp),
97 /* SMB2_SESSION_SETUP */ sizeof(struct smb2_sess_setup_rsp),
98 /* SMB2_LOGOFF */ 0,
99 /* SMB2_TREE_CONNECT */ 0,
100 /* SMB2_TREE_DISCONNECT */ 0,
101 /* SMB2_CREATE */ sizeof(struct smb2_create_rsp),
102 /* SMB2_CLOSE */ 0,
103 /* SMB2_FLUSH */ 0,
104 /* SMB2_READ */ sizeof(struct smb2_read_rsp),
105 /* SMB2_WRITE */ 0,
106 /* SMB2_LOCK */ 0,
107 /* SMB2_IOCTL */ sizeof(struct smb2_ioctl_rsp),
108 /* SMB2_CANCEL */ 0,
109 /* SMB2_ECHO */ 0,
110 /* SMB2_QUERY_DIRECTORY */ sizeof(struct smb2_query_directory_rsp),
111 /* SMB2_CHANGE_NOTIFY */ sizeof(struct smb2_change_notify_rsp),
112 /* SMB2_QUERY_INFO */ sizeof(struct smb2_query_info_rsp),
113 /* SMB2_SET_INFO */ 0,
114 /* SMB2_OPLOCK_BREAK */ 0,
115 };
116
117 #define smb2_has_data_area(cmd) (smb2_min_pdu_len[cmd] != 0)
118 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
119
get_neg_ctxt_len(struct smb2_hdr * hdr,__u32 len,__u32 non_ctxlen)120 static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
121 __u32 non_ctxlen)
122 {
123 __u16 neg_count;
124 __u32 nc_offset, size_of_pad_before_neg_ctxts;
125 struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
126
127 /* Negotiate contexts are only valid for latest dialect SMB3.11 */
128 neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
129 if ((neg_count == 0) ||
130 (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
131 return 0;
132
133 /*
134 * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
135 * which security mechanisms the server supports) make sure that
136 * the negotiate contexts start after it
137 */
138 nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
139 /*
140 * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
141 * and the latter is 1 byte bigger than the fix-sized area of the
142 * NEGOTIATE response
143 */
144 if (nc_offset + 1 < non_ctxlen) {
145 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
146 return 0;
147 } else if (nc_offset + 1 == non_ctxlen) {
148 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
149 size_of_pad_before_neg_ctxts = 0;
150 } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
151 /* has padding, but no SPNEGO blob */
152 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
153 else
154 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
155
156 /* Verify that at least minimal negotiate contexts fit within frame */
157 if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
158 pr_warn_once("negotiate context goes beyond end\n");
159 return 0;
160 }
161
162 cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
163 len - nc_offset, size_of_pad_before_neg_ctxts);
164
165 /* length of negcontexts including pad from end of sec blob to them */
166 return (len - nc_offset) + size_of_pad_before_neg_ctxts;
167 }
168
169 int
smb2_check_message(char * buf,unsigned int pdu_len,unsigned int len,struct TCP_Server_Info * server)170 smb2_check_message(char *buf, unsigned int pdu_len, unsigned int len,
171 struct TCP_Server_Info *server)
172 {
173 struct TCP_Server_Info *pserver;
174 struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
175 struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
176 int hdr_size = sizeof(struct smb2_hdr);
177 int pdu_size = sizeof(struct smb2_pdu);
178 int command;
179 __u32 calc_len; /* calculated length */
180 __u64 mid;
181 bool have_data;
182 bool data_area_overlap;
183
184 /* If server is a channel, select the primary channel */
185 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
186
187 /*
188 * Add function to do table lookup of StructureSize by command
189 * ie Validate the wct via smb2_struct_sizes table above
190 */
191 if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
192 struct smb2_transform_hdr *thdr =
193 (struct smb2_transform_hdr *)buf;
194 struct cifs_ses *ses = NULL;
195 struct cifs_ses *iter;
196
197 /* decrypt frame now that it is completely read in */
198 spin_lock(&cifs_tcp_ses_lock);
199 list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
200 if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
201 ses = iter;
202 break;
203 }
204 }
205 spin_unlock(&cifs_tcp_ses_lock);
206 if (!ses) {
207 cifs_dbg(VFS, "no decryption - session id not found\n");
208 return 1;
209 }
210 }
211
212 mid = le64_to_cpu(shdr->MessageId);
213 if (check_smb2_hdr(shdr, mid))
214 return 1;
215
216 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
217 cifs_dbg(VFS, "Invalid structure size %u\n",
218 le16_to_cpu(shdr->StructureSize));
219 return 1;
220 }
221
222 command = le16_to_cpu(shdr->Command);
223 if (command >= NUMBER_OF_SMB2_COMMANDS) {
224 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
225 return 1;
226 }
227
228 if (len < pdu_size) {
229 if ((len >= hdr_size)
230 && (shdr->Status != 0)) {
231 pdu->StructureSize2 = 0;
232 /*
233 * As with SMB/CIFS, on some error cases servers may
234 * not return wct properly
235 */
236 return 0;
237 } else {
238 cifs_dbg(VFS, "Length less than SMB header size\n");
239 }
240 return 1;
241 }
242 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
243 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
244 mid);
245 return 1;
246 }
247
248 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
249 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
250 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
251 /* error packets have 9 byte structure size */
252 cifs_dbg(VFS, "Invalid response size %u for command %d\n",
253 le16_to_cpu(pdu->StructureSize2), command);
254 return 1;
255 } else if (command == SMB2_OPLOCK_BREAK_HE
256 && (shdr->Status == 0)
257 && (le16_to_cpu(pdu->StructureSize2) != 44)
258 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
259 /* special case for SMB2.1 lease break message */
260 cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
261 le16_to_cpu(pdu->StructureSize2));
262 return 1;
263 }
264 }
265
266 if ((shdr->Status == STATUS_SUCCESS ||
267 shdr->Status == STATUS_MORE_PROCESSING_REQUIRED ||
268 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE) &&
269 smb2_has_data_area(command) &&
270 len < smb2_min_pdu_len[command]) {
271 cifs_server_dbg(VFS, "SMB2 command %d response too short: %u < %zu\n",
272 command, len, smb2_min_pdu_len[command]);
273 return 1;
274 }
275
276 have_data = false;
277 data_area_overlap = false;
278 calc_len = __smb2_calc_size(buf, &have_data, &data_area_overlap);
279
280 /* Reject responses whose data area overlaps the fixed area. */
281 if (data_area_overlap)
282 return 1;
283
284 /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
285 * be 0, and not a real miscalculation */
286 if (command == SMB2_IOCTL_HE && calc_len == 0)
287 return 0;
288
289 if (command == SMB2_NEGOTIATE_HE)
290 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
291
292 if (len != calc_len) {
293 /* create failed on symlink */
294 if (command == SMB2_CREATE_HE &&
295 shdr->Status == STATUS_STOPPED_ON_SYMLINK &&
296 len > calc_len)
297 return 0;
298 /* Windows 7 server returns 24 bytes more */
299 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
300 return 0;
301 /*
302 * Server can return one byte more due to implied bcc[0].
303 * Allow it only when there is no data area; if data_length > 0
304 * the +1 gap indicates an overreported data length rather than
305 * the bcc[0] omission.
306 */
307 if (calc_len == len + 1 && !have_data)
308 return 0;
309
310 /*
311 * Some windows servers (win2016) will pad also the final
312 * PDU in a compound to 8 bytes.
313 */
314 if (ALIGN(calc_len, 8) == len)
315 return 0;
316
317 /*
318 * MacOS server pads after SMB2.1 write response with 3 bytes
319 * of junk. Other servers match RFC1001 len to actual
320 * SMB2/SMB3 frame length (header + smb2 response specific data)
321 * Some windows servers also pad up to 8 bytes when compounding.
322 */
323 if (calc_len < len)
324 return 0;
325
326 /* Only log a message if len was really miscalculated */
327 if (unlikely(cifsFYI))
328 cifs_dbg(FYI, "Server response too short: calculated "
329 "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
330 calc_len, len, command, mid);
331 else
332 pr_warn("Server response too short: calculated length "
333 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
334 calc_len, len, command, mid);
335
336 return 1;
337 }
338 return 0;
339 }
340
341 /*
342 * Returns the pointer to the beginning of the data area. Length of the data
343 * area and the offset to it (from the beginning of the smb are also returned.
344 */
345 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * shdr)346 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
347 {
348 const int max_off = 4096;
349 const int max_len = 128 * 1024;
350
351 *off = 0;
352 *len = 0;
353
354 /* error responses do not have data area */
355 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
356 (((struct smb2_err_rsp *)shdr)->StructureSize) ==
357 SMB2_ERROR_STRUCTURE_SIZE2_LE)
358 return NULL;
359
360 /*
361 * Following commands have data areas so we have to get the location
362 * of the data buffer offset and data buffer length for the particular
363 * command.
364 */
365 switch (shdr->Command) {
366 case SMB2_NEGOTIATE:
367 *off = le16_to_cpu(
368 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
369 *len = le16_to_cpu(
370 ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
371 break;
372 case SMB2_SESSION_SETUP:
373 *off = le16_to_cpu(
374 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
375 *len = le16_to_cpu(
376 ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
377 break;
378 case SMB2_CREATE:
379 *off = le32_to_cpu(
380 ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
381 *len = le32_to_cpu(
382 ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
383 break;
384 case SMB2_QUERY_INFO:
385 *off = le16_to_cpu(
386 ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
387 *len = le32_to_cpu(
388 ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
389 break;
390 case SMB2_READ:
391 /* TODO: is this a bug ? */
392 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
393 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
394 break;
395 case SMB2_QUERY_DIRECTORY:
396 *off = le16_to_cpu(
397 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
398 *len = le32_to_cpu(
399 ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
400 break;
401 case SMB2_IOCTL:
402 *off = le32_to_cpu(
403 ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
404 *len = le32_to_cpu(
405 ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
406 break;
407 case SMB2_CHANGE_NOTIFY:
408 *off = le16_to_cpu(
409 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
410 *len = le32_to_cpu(
411 ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
412 break;
413 default:
414 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
415 break;
416 }
417
418 /*
419 * Invalid length or offset probably means data area is invalid, but
420 * we have little choice but to ignore the data area in this case.
421 */
422 if (unlikely(*off < 0 || *off > max_off ||
423 *len < 0 || *len > max_len)) {
424 cifs_dbg(VFS, "%s: invalid data area (off=%d len=%d)\n",
425 __func__, *off, *len);
426 *off = 0;
427 *len = 0;
428 } else if (*off == 0) {
429 *len = 0;
430 }
431
432 /* return pointer to beginning of data area, ie offset from SMB start */
433 if (*off > 0 && *len > 0)
434 return (char *)shdr + *off;
435 return NULL;
436 }
437
438 /*
439 * Calculate the size of the SMB message based on the fixed header, fixed
440 * parameter area, and variable data area.
441 *
442 * If have_data is not NULL, it is set when a non-empty data area is found.
443 * If data_area_overlap is not NULL, it is set when the data area overlaps
444 * the fixed area.
445 */
446 static unsigned int
__smb2_calc_size(void * buf,bool * have_data,bool * data_area_overlap)447 __smb2_calc_size(void *buf, bool *have_data, bool *data_area_overlap)
448 {
449 struct smb2_pdu *pdu = buf;
450 struct smb2_hdr *shdr = &pdu->hdr;
451 int offset; /* the offset from the beginning of SMB to data area */
452 int data_length = 0; /* the length of the variable length data area */
453 /* Structure Size has already been checked to make sure it is 64 */
454 int len = le16_to_cpu(shdr->StructureSize);
455
456 if (have_data)
457 *have_data = false;
458 if (data_area_overlap)
459 *data_area_overlap = false;
460
461 /*
462 * StructureSize2, ie length of fixed parameter area has already
463 * been checked to make sure it is the correct length.
464 */
465 len += le16_to_cpu(pdu->StructureSize2);
466
467 if (!smb2_has_data_area(le16_to_cpu(shdr->Command)))
468 goto calc_size_exit;
469
470 smb2_get_data_area_len(&offset, &data_length, shdr);
471 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
472
473 if (data_length > 0) {
474 /*
475 * Check to make sure that data area begins after fixed area,
476 * Note that last byte of the fixed area is part of data area
477 * for some commands, typically those with odd StructureSize,
478 * so we must add one to the calculation.
479 */
480 if (offset + 1 < len) {
481 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
482 offset + 1, len);
483 if (data_area_overlap)
484 *data_area_overlap = true;
485 data_length = 0;
486 goto calc_size_exit;
487 } else {
488 len = offset + data_length;
489 }
490 }
491 calc_size_exit:
492 cifs_dbg(FYI, "SMB2 len %d\n", len);
493 if (have_data)
494 *have_data = (data_length > 0);
495 return len;
496 }
497
498 unsigned int
smb2_calc_size(void * buf)499 smb2_calc_size(void *buf)
500 {
501 return __smb2_calc_size(buf, NULL, NULL);
502 }
503
504 /* Note: caller must free return buffer */
505 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)506 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
507 {
508 const char *start_of_path;
509 int len;
510
511 /* Windows doesn't allow paths beginning with \ */
512 if (from[0] == '\\')
513 start_of_path = from + 1;
514
515 /* SMB311 POSIX extensions paths do not include leading slash */
516 else if (cifs_sb_master_tlink(cifs_sb) &&
517 cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
518 (from[0] == '/')) {
519 start_of_path = from + 1;
520 } else
521 start_of_path = from;
522
523 return cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
524 cifs_sb->local_nls, cifs_remap(cifs_sb));
525 }
526
smb2_get_lease_state(struct cifsInodeInfo * cinode,unsigned int oplock)527 __le32 smb2_get_lease_state(struct cifsInodeInfo *cinode, unsigned int oplock)
528 {
529 unsigned int sbflags = cifs_sb_flags(CIFS_SB(cinode));
530 __le32 lease = 0;
531
532 if ((oplock & CIFS_CACHE_WRITE_FLG) || (sbflags & CIFS_MOUNT_RW_CACHE))
533 lease |= SMB2_LEASE_WRITE_CACHING_LE;
534 if (oplock & CIFS_CACHE_HANDLE_FLG)
535 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
536 if ((oplock & CIFS_CACHE_READ_FLG) || (sbflags & CIFS_MOUNT_RO_CACHE))
537 lease |= SMB2_LEASE_READ_CACHING_LE;
538 return lease;
539 }
540
541 struct smb2_lease_break_work {
542 struct work_struct lease_break;
543 struct tcon_link *tlink;
544 __u8 lease_key[16];
545 __le32 lease_state;
546 };
547
548 static void
cifs_ses_oplock_break(struct work_struct * work)549 cifs_ses_oplock_break(struct work_struct *work)
550 {
551 struct smb2_lease_break_work *lw = container_of(work,
552 struct smb2_lease_break_work, lease_break);
553 int rc = 0;
554
555 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
556 lw->lease_state);
557
558 cifs_dbg(FYI, "Lease release rc %d\n", rc);
559 cifs_put_tlink(lw->tlink);
560 kfree(lw);
561 }
562
563 static void
smb2_queue_pending_open_break(struct tcon_link * tlink,__u8 * lease_key,__le32 new_lease_state)564 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
565 __le32 new_lease_state)
566 {
567 struct smb2_lease_break_work *lw;
568
569 lw = kmalloc_obj(struct smb2_lease_break_work);
570 if (!lw) {
571 cifs_put_tlink(tlink);
572 return;
573 }
574
575 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
576 lw->tlink = tlink;
577 lw->lease_state = new_lease_state;
578 memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
579 queue_work(cifsiod_wq, &lw->lease_break);
580 }
581
582 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)583 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
584 {
585 __u8 lease_state;
586 struct cifsFileInfo *cfile;
587 struct cifsInodeInfo *cinode;
588 int ack_req = le32_to_cpu(rsp->Flags &
589 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
590
591 lease_state = le32_to_cpu(rsp->NewLeaseState);
592
593 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
594 cinode = CIFS_I(d_inode(cfile->dentry));
595
596 if (memcmp(cinode->lease_key, rsp->LeaseKey,
597 SMB2_LEASE_KEY_SIZE))
598 continue;
599
600 cifs_dbg(FYI, "found in the open list\n");
601 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
602 lease_state);
603
604 if (ack_req)
605 cfile->oplock_break_cancelled = false;
606 else
607 cfile->oplock_break_cancelled = true;
608
609 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
610
611 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
612 cfile->oplock_level = lease_state;
613
614 cifs_queue_oplock_break(cfile);
615 return true;
616 }
617
618 return false;
619 }
620
621 static struct cifs_pending_open *
smb2_tcon_find_pending_open_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp)622 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
623 struct smb2_lease_break *rsp)
624 {
625 __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
626 int ack_req = le32_to_cpu(rsp->Flags &
627 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
628 struct cifs_pending_open *open;
629 struct cifs_pending_open *found = NULL;
630
631 list_for_each_entry(open, &tcon->pending_opens, olist) {
632 if (memcmp(open->lease_key, rsp->LeaseKey,
633 SMB2_LEASE_KEY_SIZE))
634 continue;
635
636 if (!found && ack_req) {
637 found = open;
638 }
639
640 cifs_dbg(FYI, "found in the pending open list\n");
641 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
642 lease_state);
643
644 open->oplock = lease_state;
645 }
646
647 return found;
648 }
649
650 static bool
smb2_is_valid_lease_break(char * buffer,struct TCP_Server_Info * server)651 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
652 {
653 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
654 struct TCP_Server_Info *pserver;
655 struct cifs_ses *ses;
656 struct cifs_tcon *tcon;
657 struct cifs_pending_open *open;
658
659 /* Trace receipt of lease break request from server */
660 trace_smb3_lease_break_enter(le32_to_cpu(rsp->CurrentLeaseState),
661 le32_to_cpu(rsp->Flags),
662 le16_to_cpu(rsp->Epoch),
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 cifs_dbg(FYI, "Checking for lease break\n");
669
670 /* If server is a channel, select the primary channel */
671 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
672
673 /* look up tcon based on tid & uid */
674 spin_lock(&cifs_tcp_ses_lock);
675 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
676 if (cifs_ses_exiting(ses))
677 continue;
678 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
679 spin_lock(&tcon->open_file_lock);
680 cifs_stats_inc(
681 &tcon->stats.cifs_stats.num_oplock_brks);
682 if (smb2_tcon_has_lease(tcon, rsp)) {
683 spin_unlock(&tcon->open_file_lock);
684 spin_unlock(&cifs_tcp_ses_lock);
685 return true;
686 }
687 open = smb2_tcon_find_pending_open_lease(tcon,
688 rsp);
689 if (open) {
690 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
691 struct tcon_link *tlink;
692
693 tlink = cifs_get_tlink(open->tlink);
694 memcpy(lease_key, open->lease_key,
695 SMB2_LEASE_KEY_SIZE);
696 spin_unlock(&tcon->open_file_lock);
697 spin_unlock(&cifs_tcp_ses_lock);
698 smb2_queue_pending_open_break(tlink,
699 lease_key,
700 rsp->NewLeaseState);
701 return true;
702 }
703 spin_unlock(&tcon->open_file_lock);
704
705 if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
706 spin_unlock(&cifs_tcp_ses_lock);
707 return true;
708 }
709 }
710 }
711 spin_unlock(&cifs_tcp_ses_lock);
712 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
713 trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
714 le32_to_cpu(rsp->Flags),
715 le16_to_cpu(rsp->Epoch),
716 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
717 le64_to_cpu(rsp->hdr.SessionId),
718 *((u64 *)rsp->LeaseKey),
719 *((u64 *)&rsp->LeaseKey[8]));
720
721 return false;
722 }
723
724 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)725 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
726 {
727 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
728 struct TCP_Server_Info *pserver;
729 struct cifs_ses *ses;
730 struct cifs_tcon *tcon;
731 struct cifsInodeInfo *cinode;
732 struct cifsFileInfo *cfile;
733
734 cifs_dbg(FYI, "Checking for oplock break\n");
735
736 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
737 return false;
738
739 if (rsp->StructureSize !=
740 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
741 if (le16_to_cpu(rsp->StructureSize) == 44)
742 return smb2_is_valid_lease_break(buffer, server);
743 else
744 return false;
745 }
746
747 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
748
749 /* If server is a channel, select the primary channel */
750 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
751
752 /* look up tcon based on tid & uid */
753 spin_lock(&cifs_tcp_ses_lock);
754 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
755 if (cifs_ses_exiting(ses))
756 continue;
757 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
758
759 spin_lock(&tcon->open_file_lock);
760 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
761 if (rsp->PersistentFid !=
762 cfile->fid.persistent_fid ||
763 rsp->VolatileFid !=
764 cfile->fid.volatile_fid)
765 continue;
766
767 cifs_dbg(FYI, "file id match, oplock break\n");
768 cifs_stats_inc(
769 &tcon->stats.cifs_stats.num_oplock_brks);
770 cinode = CIFS_I(d_inode(cfile->dentry));
771 spin_lock(&cfile->file_info_lock);
772 if (!CIFS_CACHE_WRITE(cinode) &&
773 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
774 cfile->oplock_break_cancelled = true;
775 else
776 cfile->oplock_break_cancelled = false;
777
778 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
779 &cinode->flags);
780
781 cfile->oplock_epoch = 0;
782 cfile->oplock_level = rsp->OplockLevel;
783
784 spin_unlock(&cfile->file_info_lock);
785
786 cifs_queue_oplock_break(cfile);
787
788 spin_unlock(&tcon->open_file_lock);
789 spin_unlock(&cifs_tcp_ses_lock);
790 return true;
791 }
792 spin_unlock(&tcon->open_file_lock);
793 }
794 }
795 spin_unlock(&cifs_tcp_ses_lock);
796 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
797 trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
798 le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
799 le64_to_cpu(rsp->hdr.SessionId));
800
801 return true;
802 }
803
804 void
smb2_cancelled_close_fid(struct work_struct * work)805 smb2_cancelled_close_fid(struct work_struct *work)
806 {
807 struct close_cancelled_open *cancelled = container_of(work,
808 struct close_cancelled_open, work);
809 struct cifs_tcon *tcon = cancelled->tcon;
810 int rc;
811
812 if (cancelled->mid)
813 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
814 cancelled->mid);
815 else
816 cifs_tcon_dbg(VFS, "Close interrupted close\n");
817
818 rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
819 cancelled->fid.volatile_fid);
820 if (rc)
821 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
822
823 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close_fid);
824 kfree(cancelled);
825 }
826
827 /*
828 * Caller should already has an extra reference to @tcon
829 * This function is used to queue work to close a handle to prevent leaks
830 * on the server.
831 * We handle two cases. If an open was interrupted after we sent the
832 * SMB2_CREATE to the server but before we processed the reply, and second
833 * if a close was interrupted before we sent the SMB2_CLOSE to the server.
834 */
835 static int
__smb2_handle_cancelled_cmd(struct cifs_tcon * tcon,__u16 cmd,__u64 mid,__u64 persistent_fid,__u64 volatile_fid,bool account_remote_open)836 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
837 __u64 persistent_fid, __u64 volatile_fid,
838 bool account_remote_open)
839 {
840 struct close_cancelled_open *cancelled;
841
842 cancelled = kzalloc_obj(*cancelled);
843 if (!cancelled)
844 return -ENOMEM;
845
846 cancelled->fid.persistent_fid = persistent_fid;
847 cancelled->fid.volatile_fid = volatile_fid;
848 cancelled->tcon = tcon;
849 cancelled->cmd = cmd;
850 cancelled->mid = mid;
851 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
852 if (account_remote_open)
853 atomic_inc(&tcon->num_remote_opens);
854 WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
855
856 return 0;
857 }
858
859 int
smb2_handle_cancelled_close(struct cifs_tcon * tcon,__u64 persistent_fid,__u64 volatile_fid)860 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
861 __u64 volatile_fid)
862 {
863 int rc;
864
865 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
866 spin_lock(&tcon->tc_lock);
867 if (tcon->tc_count <= 0) {
868 struct TCP_Server_Info *server = NULL;
869
870 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
871 netfs_trace_tcon_ref_see_cancelled_close);
872 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
873 spin_unlock(&tcon->tc_lock);
874
875 if (tcon->ses) {
876 server = tcon->ses->server;
877 cifs_server_dbg(FYI,
878 "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
879 tcon->tid, persistent_fid, volatile_fid);
880 }
881
882 return 0;
883 }
884 tcon->tc_count++;
885 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
886 netfs_trace_tcon_ref_get_cancelled_close);
887 spin_unlock(&tcon->tc_lock);
888
889 rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
890 persistent_fid, volatile_fid, false);
891 if (rc)
892 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_close);
893
894 return rc;
895 }
896
897 int
smb2_handle_cancelled_mid(struct mid_q_entry * mid,struct TCP_Server_Info * server)898 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
899 {
900 struct smb2_hdr *hdr = mid->resp_buf;
901 struct smb2_create_rsp *rsp = mid->resp_buf;
902 struct cifs_tcon *tcon;
903 int rc;
904
905 if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
906 hdr->Status != STATUS_SUCCESS)
907 return 0;
908
909 tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
910 le32_to_cpu(hdr->Id.SyncId.TreeId));
911 if (!tcon)
912 return -ENOENT;
913
914 rc = __smb2_handle_cancelled_cmd(tcon,
915 le16_to_cpu(hdr->Command),
916 le64_to_cpu(hdr->MessageId),
917 rsp->PersistentFileId,
918 rsp->VolatileFileId, true);
919 if (rc)
920 cifs_put_tcon(tcon, netfs_trace_tcon_ref_put_cancelled_mid);
921
922 return rc;
923 }
924
925 /**
926 * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
927 *
928 * Assumes @iov does not contain the rfc1002 length and iov[0] has the
929 * SMB2 header.
930 *
931 * @ses: server session structure
932 * @server: pointer to server info
933 * @iov: array containing the SMB request we will send to the server
934 * @nvec: number of array entries for the iov
935 */
936 void
smb311_update_preauth_hash(struct cifs_ses * ses,struct TCP_Server_Info * server,struct kvec * iov,int nvec)937 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
938 struct kvec *iov, int nvec)
939 {
940 int i;
941 struct smb2_hdr *hdr;
942 struct sha512_ctx sha_ctx;
943
944 hdr = (struct smb2_hdr *)iov[0].iov_base;
945 /* neg prot are always taken */
946 if (hdr->Command == SMB2_NEGOTIATE)
947 goto ok;
948
949 /*
950 * If we process a command which wasn't a negprot it means the
951 * neg prot was already done, so the server dialect was set
952 * and we can test it. Preauth requires 3.1.1 for now.
953 */
954 if (server->dialect != SMB311_PROT_ID)
955 return;
956
957 if (hdr->Command != SMB2_SESSION_SETUP)
958 return;
959
960 /* skip last sess setup response */
961 if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
962 && (hdr->Status == NT_STATUS_OK
963 || (hdr->Status !=
964 cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
965 return;
966
967 ok:
968 sha512_init(&sha_ctx);
969 sha512_update(&sha_ctx, ses->preauth_sha_hash, SMB2_PREAUTH_HASH_SIZE);
970 for (i = 0; i < nvec; i++)
971 sha512_update(&sha_ctx, iov[i].iov_base, iov[i].iov_len);
972 sha512_final(&sha_ctx, ses->preauth_sha_hash);
973 }
974