fs/cifs/smb2misc.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002,2011
   5  *                 Etersoft, 2012
   6  *   Author(s): Steve French (sfrench@us.ibm.com)
   7  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
   8  *
   9  */
  10 #include <linux/ctype.h>
  11 #include "cifsglob.h"
  12 #include "cifsproto.h"
  13 #include "smb2proto.h"
  14 #include "cifs_debug.h"
  15 #include "cifs_unicode.h"
  16 #include "smb2status.h"
  17 #include "smb2glob.h"
  18 #include "nterr.h"
  19 #include "cached_dir.h"
  20
  21 static int
  22 check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
  23 {
  24         __u64 wire_mid = le64_to_cpu(shdr->MessageId);
  25
  26         /*
  27          * Make sure that this really is an SMB, that it is a response,
  28          * and that the message ids match.
  29          */
  30         if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
  31             (mid == wire_mid)) {
  32                 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
  33                         return 0;
  34                 else {
  35                         /* only one valid case where server sends us request */
  36                         if (shdr->Command == SMB2_OPLOCK_BREAK)
  37                                 return 0;
  38                         else
  39                                 cifs_dbg(VFS, "Received Request not response\n");
  40                 }
  41         } else { /* bad signature or mid */
  42                 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
  43                         cifs_dbg(VFS, "Bad protocol string signature header %x\n",
  44                                  le32_to_cpu(shdr->ProtocolId));
  45                 if (mid != wire_mid)
  46                         cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
  47                                  mid, wire_mid);
  48         }
  49         cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
  50         return 1;
  51 }
  52
  53 /*
  54  *  The following table defines the expected "StructureSize" of SMB2 responses
  55  *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
  56  *
  57  *  Note that commands are defined in smb2pdu.h in le16 but the array below is
  58  *  indexed by command in host byte order
  59  */
  60 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
  61         /* SMB2_NEGOTIATE */ cpu_to_le16(65),
  62         /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
  63         /* SMB2_LOGOFF */ cpu_to_le16(4),
  64         /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
  65         /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
  66         /* SMB2_CREATE */ cpu_to_le16(89),
  67         /* SMB2_CLOSE */ cpu_to_le16(60),
  68         /* SMB2_FLUSH */ cpu_to_le16(4),
  69         /* SMB2_READ */ cpu_to_le16(17),
  70         /* SMB2_WRITE */ cpu_to_le16(17),
  71         /* SMB2_LOCK */ cpu_to_le16(4),
  72         /* SMB2_IOCTL */ cpu_to_le16(49),
  73         /* BB CHECK this ... not listed in documentation */
  74         /* SMB2_CANCEL */ cpu_to_le16(0),
  75         /* SMB2_ECHO */ cpu_to_le16(4),
  76         /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
  77         /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
  78         /* SMB2_QUERY_INFO */ cpu_to_le16(9),
  79         /* SMB2_SET_INFO */ cpu_to_le16(2),
  80         /* BB FIXME can also be 44 for lease break */
  81         /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
  82 };
  83
  84 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
  85
  86 static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
  87                               __u32 non_ctxlen)
  88 {
  89         __u16 neg_count;
  90         __u32 nc_offset, size_of_pad_before_neg_ctxts;
  91         struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
  92
  93         /* Negotiate contexts are only valid for latest dialect SMB3.11 */
  94         neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
  95         if ((neg_count == 0) ||
  96            (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
  97                 return 0;
  98
  99         /*
 100          * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
 101          * which security mechanisms the server supports) make sure that
 102          * the negotiate contexts start after it
 103          */
 104         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
 105         /*
 106          * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
 107          * and the latter is 1 byte bigger than the fix-sized area of the
 108          * NEGOTIATE response
 109          */
 110         if (nc_offset + 1 < non_ctxlen) {
 111                 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
 112                 return 0;
 113         } else if (nc_offset + 1 == non_ctxlen) {
 114                 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
 115                 size_of_pad_before_neg_ctxts = 0;
 116         } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
 117                 /* has padding, but no SPNEGO blob */
 118                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
 119         else
 120                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 121
 122         /* Verify that at least minimal negotiate contexts fit within frame */
 123         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
 124                 pr_warn_once("negotiate context goes beyond end\n");
 125                 return 0;
 126         }
 127
 128         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
 129                 len - nc_offset, size_of_pad_before_neg_ctxts);
 130
 131         /* length of negcontexts including pad from end of sec blob to them */
 132         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
 133 }
 134
 135 int
 136 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
 137 {
 138         struct TCP_Server_Info *pserver;
 139         struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
 140         struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
 141         int hdr_size = sizeof(struct smb2_hdr);
 142         int pdu_size = sizeof(struct smb2_pdu);
 143         int command;
 144         __u32 calc_len; /* calculated length */
 145         __u64 mid;
 146
 147         /* If server is a channel, select the primary channel */
 148         pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
 149
 150         /*
 151          * Add function to do table lookup of StructureSize by command
 152          * ie Validate the wct via smb2_struct_sizes table above
 153          */
 154         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 155                 struct smb2_transform_hdr *thdr =
 156                         (struct smb2_transform_hdr *)buf;
 157                 struct cifs_ses *ses = NULL;
 158                 struct cifs_ses *iter;
 159
 160                 /* decrypt frame now that it is completely read in */
 161                 spin_lock(&cifs_tcp_ses_lock);
 162                 list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
 163                         if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
 164                                 ses = iter;
 165                                 break;
 166                         }
 167                 }
 168                 spin_unlock(&cifs_tcp_ses_lock);
 169                 if (!ses) {
 170                         cifs_dbg(VFS, "no decryption - session id not found\n");
 171                         return 1;
 172                 }
 173         }
 174
 175         mid = le64_to_cpu(shdr->MessageId);
 176         if (len < pdu_size) {
 177                 if ((len >= hdr_size)
 178                     && (shdr->Status != 0)) {
 179                         pdu->StructureSize2 = 0;
 180                         /*
 181                          * As with SMB/CIFS, on some error cases servers may
 182                          * not return wct properly
 183                          */
 184                         return 0;
 185                 } else {
 186                         cifs_dbg(VFS, "Length less than SMB header size\n");
 187                 }
 188                 return 1;
 189         }
 190         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 191                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 192                          mid);
 193                 return 1;
 194         }
 195
 196         if (check_smb2_hdr(shdr, mid))
 197                 return 1;
 198
 199         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 200                 cifs_dbg(VFS, "Invalid structure size %u\n",
 201                          le16_to_cpu(shdr->StructureSize));
 202                 return 1;
 203         }
 204
 205         command = le16_to_cpu(shdr->Command);
 206         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 207                 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
 208                 return 1;
 209         }
 210
 211         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 212                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 213                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
 214                         /* error packets have 9 byte structure size */
 215                         cifs_dbg(VFS, "Invalid response size %u for command %d\n",
 216                                  le16_to_cpu(pdu->StructureSize2), command);
 217                         return 1;
 218                 } else if (command == SMB2_OPLOCK_BREAK_HE
 219                            && (shdr->Status == 0)
 220                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 221                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 222                         /* special case for SMB2.1 lease break message */
 223                         cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
 224                                  le16_to_cpu(pdu->StructureSize2));
 225                         return 1;
 226                 }
 227         }
 228
 229         calc_len = smb2_calc_size(buf);
 230
 231         /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
 232          * be 0, and not a real miscalculation */
 233         if (command == SMB2_IOCTL_HE && calc_len == 0)
 234                 return 0;
 235
 236         if (command == SMB2_NEGOTIATE_HE)
 237                 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
 238
 239         if (len != calc_len) {
 240                 /* create failed on symlink */
 241                 if (command == SMB2_CREATE_HE &&
 242                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 243                         return 0;
 244                 /* Windows 7 server returns 24 bytes more */
 245                 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 246                         return 0;
 247                 /* server can return one byte more due to implied bcc[0] */
 248                 if (calc_len == len + 1)
 249                         return 0;
 250
 251                 /*
 252                  * Some windows servers (win2016) will pad also the final
 253                  * PDU in a compound to 8 bytes.
 254                  */
 255                 if (ALIGN(calc_len, 8) == len)
 256                         return 0;
 257
 258                 /*
 259                  * MacOS server pads after SMB2.1 write response with 3 bytes
 260                  * of junk. Other servers match RFC1001 len to actual
 261                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 262                  * Some windows servers also pad up to 8 bytes when compounding.
 263                  */
 264                 if (calc_len < len)
 265                         return 0;
 266
 267                 /* Only log a message if len was really miscalculated */
 268                 if (unlikely(cifsFYI))
 269                         cifs_dbg(FYI, "Server response too short: calculated "
 270                                  "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
 271                                  calc_len, len, command, mid);
 272                 else
 273                         pr_warn("Server response too short: calculated length "
 274                                 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
 275                                 calc_len, len, command, mid);
 276
 277                 return 1;
 278         }
 279         return 0;
 280 }
 281
 282 /*
 283  * The size of the variable area depends on the offset and length fields
 284  * located in different fields for various SMB2 responses. SMB2 responses
 285  * with no variable length info, show an offset of zero for the offset field.
 286  */
 287 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 288         /* SMB2_NEGOTIATE */ true,
 289         /* SMB2_SESSION_SETUP */ true,
 290         /* SMB2_LOGOFF */ false,
 291         /* SMB2_TREE_CONNECT */ false,
 292         /* SMB2_TREE_DISCONNECT */ false,
 293         /* SMB2_CREATE */ true,
 294         /* SMB2_CLOSE */ false,
 295         /* SMB2_FLUSH */ false,
 296         /* SMB2_READ */ true,
 297         /* SMB2_WRITE */ false,
 298         /* SMB2_LOCK */ false,
 299         /* SMB2_IOCTL */ true,
 300         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 301         /* SMB2_ECHO */ false,
 302         /* SMB2_QUERY_DIRECTORY */ true,
 303         /* SMB2_CHANGE_NOTIFY */ true,
 304         /* SMB2_QUERY_INFO */ true,
 305         /* SMB2_SET_INFO */ false,
 306         /* SMB2_OPLOCK_BREAK */ false
 307 };
 308
 309 /*
 310  * Returns the pointer to the beginning of the data area. Length of the data
 311  * area and the offset to it (from the beginning of the smb are also returned.
 312  */
 313 char *
 314 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
 315 {
 316         *off = 0;
 317         *len = 0;
 318
 319         /* error responses do not have data area */
 320         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 321             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 322                                                 SMB2_ERROR_STRUCTURE_SIZE2_LE)
 323                 return NULL;
 324
 325         /*
 326          * Following commands have data areas so we have to get the location
 327          * of the data buffer offset and data buffer length for the particular
 328          * command.
 329          */
 330         switch (shdr->Command) {
 331         case SMB2_NEGOTIATE:
 332                 *off = le16_to_cpu(
 333                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 334                 *len = le16_to_cpu(
 335                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 336                 break;
 337         case SMB2_SESSION_SETUP:
 338                 *off = le16_to_cpu(
 339                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 340                 *len = le16_to_cpu(
 341                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 342                 break;
 343         case SMB2_CREATE:
 344                 *off = le32_to_cpu(
 345                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 346                 *len = le32_to_cpu(
 347                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 348                 break;
 349         case SMB2_QUERY_INFO:
 350                 *off = le16_to_cpu(
 351                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 352                 *len = le32_to_cpu(
 353                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 354                 break;
 355         case SMB2_READ:
 356                 /* TODO: is this a bug ? */
 357                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 358                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 359                 break;
 360         case SMB2_QUERY_DIRECTORY:
 361                 *off = le16_to_cpu(
 362                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 363                 *len = le32_to_cpu(
 364                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 365                 break;
 366         case SMB2_IOCTL:
 367                 *off = le32_to_cpu(
 368                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 369                 *len = le32_to_cpu(
 370                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 371                 break;
 372         case SMB2_CHANGE_NOTIFY:
 373                 *off = le16_to_cpu(
 374                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
 375                 *len = le32_to_cpu(
 376                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
 377                 break;
 378         default:
 379                 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
 380                 break;
 381         }
 382
 383         /*
 384          * Invalid length or offset probably means data area is invalid, but
 385          * we have little choice but to ignore the data area in this case.
 386          */
 387         if (*off > 4096) {
 388                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 389                 *len = 0;
 390                 *off = 0;
 391         } else if (*off < 0) {
 392                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 393                          *off);
 394                 *off = 0;
 395                 *len = 0;
 396         } else if (*len < 0) {
 397                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 398                          *len);
 399                 *len = 0;
 400         } else if (*len > 128 * 1024) {
 401                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 402                 *len = 0;
 403         }
 404
 405         /* return pointer to beginning of data area, ie offset from SMB start */
 406         if ((*off != 0) && (*len != 0))
 407                 return (char *)shdr + *off;
 408         else
 409                 return NULL;
 410 }
 411
 412 /*
 413  * Calculate the size of the SMB message based on the fixed header
 414  * portion, the number of word parameters and the data portion of the message.
 415  */
 416 unsigned int
 417 smb2_calc_size(void *buf)
 418 {
 419         struct smb2_pdu *pdu = buf;
 420         struct smb2_hdr *shdr = &pdu->hdr;
 421         int offset; /* the offset from the beginning of SMB to data area */
 422         int data_length; /* the length of the variable length data area */
 423         /* Structure Size has already been checked to make sure it is 64 */
 424         int len = le16_to_cpu(shdr->StructureSize);
 425
 426         /*
 427          * StructureSize2, ie length of fixed parameter area has already
 428          * been checked to make sure it is the correct length.
 429          */
 430         len += le16_to_cpu(pdu->StructureSize2);
 431
 432         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 433                 goto calc_size_exit;
 434
 435         smb2_get_data_area_len(&offset, &data_length, shdr);
 436         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 437
 438         if (data_length > 0) {
 439                 /*
 440                  * Check to make sure that data area begins after fixed area,
 441                  * Note that last byte of the fixed area is part of data area
 442                  * for some commands, typically those with odd StructureSize,
 443                  * so we must add one to the calculation.
 444                  */
 445                 if (offset + 1 < len) {
 446                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
 447                                  offset + 1, len);
 448                         data_length = 0;
 449                 } else {
 450                         len = offset + data_length;
 451                 }
 452         }
 453 calc_size_exit:
 454         cifs_dbg(FYI, "SMB2 len %d\n", len);
 455         return len;
 456 }
 457
 458 /* Note: caller must free return buffer */
 459 __le16 *
 460 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 461 {
 462         int len;
 463         const char *start_of_path;
 464         __le16 *to;
 465         int map_type;
 466
 467         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 468                 map_type = SFM_MAP_UNI_RSVD;
 469         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 470                 map_type = SFU_MAP_UNI_RSVD;
 471         else
 472                 map_type = NO_MAP_UNI_RSVD;
 473
 474         /* Windows doesn't allow paths beginning with \ */
 475         if (from[0] == '\\')
 476                 start_of_path = from + 1;
 477
 478         /* SMB311 POSIX extensions paths do not include leading slash */
 479         else if (cifs_sb_master_tlink(cifs_sb) &&
 480                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 481                  (from[0] == '/')) {
 482                 start_of_path = from + 1;
 483         } else
 484                 start_of_path = from;
 485
 486         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 487                                    cifs_sb->local_nls, map_type);
 488         return to;
 489 }
 490
 491 __le32
 492 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 493 {
 494         __le32 lease = 0;
 495
 496         if (CIFS_CACHE_WRITE(cinode))
 497                 lease |= SMB2_LEASE_WRITE_CACHING_LE;
 498         if (CIFS_CACHE_HANDLE(cinode))
 499                 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
 500         if (CIFS_CACHE_READ(cinode))
 501                 lease |= SMB2_LEASE_READ_CACHING_LE;
 502         return lease;
 503 }
 504
 505 struct smb2_lease_break_work {
 506         struct work_struct lease_break;
 507         struct tcon_link *tlink;
 508         __u8 lease_key[16];
 509         __le32 lease_state;
 510 };
 511
 512 static void
 513 cifs_ses_oplock_break(struct work_struct *work)
 514 {
 515         struct smb2_lease_break_work *lw = container_of(work,
 516                                 struct smb2_lease_break_work, lease_break);
 517         int rc = 0;
 518
 519         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 520                               lw->lease_state);
 521
 522         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 523         cifs_put_tlink(lw->tlink);
 524         kfree(lw);
 525 }
 526
 527 static void
 528 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
 529                               __le32 new_lease_state)
 530 {
 531         struct smb2_lease_break_work *lw;
 532
 533         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 534         if (!lw) {
 535                 cifs_put_tlink(tlink);
 536                 return;
 537         }
 538
 539         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 540         lw->tlink = tlink;
 541         lw->lease_state = new_lease_state;
 542         memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
 543         queue_work(cifsiod_wq, &lw->lease_break);
 544 }
 545
 546 static bool
 547 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 548 {
 549         __u8 lease_state;
 550         struct cifsFileInfo *cfile;
 551         struct cifsInodeInfo *cinode;
 552         int ack_req = le32_to_cpu(rsp->Flags &
 553                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 554
 555         lease_state = le32_to_cpu(rsp->NewLeaseState);
 556
 557         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 558                 cinode = CIFS_I(d_inode(cfile->dentry));
 559
 560                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 561                                                         SMB2_LEASE_KEY_SIZE))
 562                         continue;
 563
 564                 cifs_dbg(FYI, "found in the open list\n");
 565                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 566                          lease_state);
 567
 568                 if (ack_req)
 569                         cfile->oplock_break_cancelled = false;
 570                 else
 571                         cfile->oplock_break_cancelled = true;
 572
 573                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 574
 575                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 576                 cfile->oplock_level = lease_state;
 577
 578                 cifs_queue_oplock_break(cfile);
 579                 return true;
 580         }
 581
 582         return false;
 583 }
 584
 585 static struct cifs_pending_open *
 586 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
 587                                   struct smb2_lease_break *rsp)
 588 {
 589         __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
 590         int ack_req = le32_to_cpu(rsp->Flags &
 591                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 592         struct cifs_pending_open *open;
 593         struct cifs_pending_open *found = NULL;
 594
 595         list_for_each_entry(open, &tcon->pending_opens, olist) {
 596                 if (memcmp(open->lease_key, rsp->LeaseKey,
 597                            SMB2_LEASE_KEY_SIZE))
 598                         continue;
 599
 600                 if (!found && ack_req) {
 601                         found = open;
 602                 }
 603
 604                 cifs_dbg(FYI, "found in the pending open list\n");
 605                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 606                          lease_state);
 607
 608                 open->oplock = lease_state;
 609         }
 610
 611         return found;
 612 }
 613
 614 static bool
 615 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
 616 {
 617         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 618         struct TCP_Server_Info *pserver;
 619         struct cifs_ses *ses;
 620         struct cifs_tcon *tcon;
 621         struct cifs_pending_open *open;
 622
 623         cifs_dbg(FYI, "Checking for lease break\n");
 624
 625         /* If server is a channel, select the primary channel */
 626         pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
 627
 628         /* look up tcon based on tid & uid */
 629         spin_lock(&cifs_tcp_ses_lock);
 630         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 631                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 632                         spin_lock(&tcon->open_file_lock);
 633                         cifs_stats_inc(
 634                                        &tcon->stats.cifs_stats.num_oplock_brks);
 635                         if (smb2_tcon_has_lease(tcon, rsp)) {
 636                                 spin_unlock(&tcon->open_file_lock);
 637                                 spin_unlock(&cifs_tcp_ses_lock);
 638                                 return true;
 639                         }
 640                         open = smb2_tcon_find_pending_open_lease(tcon,
 641                                                                  rsp);
 642                         if (open) {
 643                                 __u8 lease_key[SMB2_LEASE_KEY_SIZE];
 644                                 struct tcon_link *tlink;
 645
 646                                 tlink = cifs_get_tlink(open->tlink);
 647                                 memcpy(lease_key, open->lease_key,
 648                                        SMB2_LEASE_KEY_SIZE);
 649                                 spin_unlock(&tcon->open_file_lock);
 650                                 spin_unlock(&cifs_tcp_ses_lock);
 651                                 smb2_queue_pending_open_break(tlink,
 652                                                               lease_key,
 653                                                               rsp->NewLeaseState);
 654                                 return true;
 655                         }
 656                         spin_unlock(&tcon->open_file_lock);
 657
 658                         if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
 659                                 spin_unlock(&cifs_tcp_ses_lock);
 660                                 return true;
 661                         }
 662                 }
 663         }
 664         spin_unlock(&cifs_tcp_ses_lock);
 665         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 666         trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
 667                                    le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
 668                                    le64_to_cpu(rsp->hdr.SessionId),
 669                                    *((u64 *)rsp->LeaseKey),
 670                                    *((u64 *)&rsp->LeaseKey[8]));
 671
 672         return false;
 673 }
 674
 675 bool
 676 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 677 {
 678         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 679         struct TCP_Server_Info *pserver;
 680         struct cifs_ses *ses;
 681         struct cifs_tcon *tcon;
 682         struct cifsInodeInfo *cinode;
 683         struct cifsFileInfo *cfile;
 684
 685         cifs_dbg(FYI, "Checking for oplock break\n");
 686
 687         if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
 688                 return false;
 689
 690         if (rsp->StructureSize !=
 691                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 692                 if (le16_to_cpu(rsp->StructureSize) == 44)
 693                         return smb2_is_valid_lease_break(buffer, server);
 694                 else
 695                         return false;
 696         }
 697
 698         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 699
 700         /* If server is a channel, select the primary channel */
 701         pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
 702
 703         /* look up tcon based on tid & uid */
 704         spin_lock(&cifs_tcp_ses_lock);
 705         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 706                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 707
 708                         spin_lock(&tcon->open_file_lock);
 709                         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 710                                 if (rsp->PersistentFid !=
 711                                     cfile->fid.persistent_fid ||
 712                                     rsp->VolatileFid !=
 713                                     cfile->fid.volatile_fid)
 714                                         continue;
 715
 716                                 cifs_dbg(FYI, "file id match, oplock break\n");
 717                                 cifs_stats_inc(
 718                                     &tcon->stats.cifs_stats.num_oplock_brks);
 719                                 cinode = CIFS_I(d_inode(cfile->dentry));
 720                                 spin_lock(&cfile->file_info_lock);
 721                                 if (!CIFS_CACHE_WRITE(cinode) &&
 722                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 723                                         cfile->oplock_break_cancelled = true;
 724                                 else
 725                                         cfile->oplock_break_cancelled = false;
 726
 727                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 728                                         &cinode->flags);
 729
 730                                 cfile->oplock_epoch = 0;
 731                                 cfile->oplock_level = rsp->OplockLevel;
 732
 733                                 spin_unlock(&cfile->file_info_lock);
 734
 735                                 cifs_queue_oplock_break(cfile);
 736
 737                                 spin_unlock(&tcon->open_file_lock);
 738                                 spin_unlock(&cifs_tcp_ses_lock);
 739                                 return true;
 740                         }
 741                         spin_unlock(&tcon->open_file_lock);
 742                 }
 743         }
 744         spin_unlock(&cifs_tcp_ses_lock);
 745         cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
 746         trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
 747                                   le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
 748                                   le64_to_cpu(rsp->hdr.SessionId));
 749
 750         return true;
 751 }
 752
 753 void
 754 smb2_cancelled_close_fid(struct work_struct *work)
 755 {
 756         struct close_cancelled_open *cancelled = container_of(work,
 757                                         struct close_cancelled_open, work);
 758         struct cifs_tcon *tcon = cancelled->tcon;
 759         int rc;
 760
 761         if (cancelled->mid)
 762                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
 763                               cancelled->mid);
 764         else
 765                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
 766
 767         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
 768                         cancelled->fid.volatile_fid);
 769         if (rc)
 770                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 771
 772         cifs_put_tcon(tcon);
 773         kfree(cancelled);
 774 }
 775
 776 /*
 777  * Caller should already has an extra reference to @tcon
 778  * This function is used to queue work to close a handle to prevent leaks
 779  * on the server.
 780  * We handle two cases. If an open was interrupted after we sent the
 781  * SMB2_CREATE to the server but before we processed the reply, and second
 782  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
 783  */
 784 static int
 785 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 786                             __u64 persistent_fid, __u64 volatile_fid)
 787 {
 788         struct close_cancelled_open *cancelled;
 789
 790         cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
 791         if (!cancelled)
 792                 return -ENOMEM;
 793
 794         cancelled->fid.persistent_fid = persistent_fid;
 795         cancelled->fid.volatile_fid = volatile_fid;
 796         cancelled->tcon = tcon;
 797         cancelled->cmd = cmd;
 798         cancelled->mid = mid;
 799         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 800         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
 801
 802         return 0;
 803 }
 804
 805 int
 806 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 807                             __u64 volatile_fid)
 808 {
 809         int rc;
 810
 811         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 812         spin_lock(&cifs_tcp_ses_lock);
 813         if (tcon->tc_count <= 0) {
 814                 struct TCP_Server_Info *server = NULL;
 815
 816                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 817                 spin_unlock(&cifs_tcp_ses_lock);
 818
 819                 if (tcon->ses)
 820                         server = tcon->ses->server;
 821
 822                 cifs_server_dbg(FYI, "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
 823                                 tcon->tid, persistent_fid, volatile_fid);
 824
 825                 return 0;
 826         }
 827         tcon->tc_count++;
 828         spin_unlock(&cifs_tcp_ses_lock);
 829
 830         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 831                                          persistent_fid, volatile_fid);
 832         if (rc)
 833                 cifs_put_tcon(tcon);
 834
 835         return rc;
 836 }
 837
 838 int
 839 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 840 {
 841         struct smb2_hdr *hdr = mid->resp_buf;
 842         struct smb2_create_rsp *rsp = mid->resp_buf;
 843         struct cifs_tcon *tcon;
 844         int rc;
 845
 846         if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
 847             hdr->Status != STATUS_SUCCESS)
 848                 return 0;
 849
 850         tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
 851                                   le32_to_cpu(hdr->Id.SyncId.TreeId));
 852         if (!tcon)
 853                 return -ENOENT;
 854
 855         rc = __smb2_handle_cancelled_cmd(tcon,
 856                                          le16_to_cpu(hdr->Command),
 857                                          le64_to_cpu(hdr->MessageId),
 858                                          rsp->PersistentFileId,
 859                                          rsp->VolatileFileId);
 860         if (rc)
 861                 cifs_put_tcon(tcon);
 862
 863         return rc;
 864 }
 865
 866 /**
 867  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 868  *
 869  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 870  * SMB2 header.
 871  *
 872  * @ses:        server session structure
 873  * @server:     pointer to server info
 874  * @iov:        array containing the SMB request we will send to the server
 875  * @nvec:       number of array entries for the iov
 876  */
 877 int
 878 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
 879                            struct kvec *iov, int nvec)
 880 {
 881         int i, rc;
 882         struct smb2_hdr *hdr;
 883         struct shash_desc *sha512 = NULL;
 884
 885         hdr = (struct smb2_hdr *)iov[0].iov_base;
 886         /* neg prot are always taken */
 887         if (hdr->Command == SMB2_NEGOTIATE)
 888                 goto ok;
 889
 890         /*
 891          * If we process a command which wasn't a negprot it means the
 892          * neg prot was already done, so the server dialect was set
 893          * and we can test it. Preauth requires 3.1.1 for now.
 894          */
 895         if (server->dialect != SMB311_PROT_ID)
 896                 return 0;
 897
 898         if (hdr->Command != SMB2_SESSION_SETUP)
 899                 return 0;
 900
 901         /* skip last sess setup response */
 902         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 903             && (hdr->Status == NT_STATUS_OK
 904                 || (hdr->Status !=
 905                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
 906                 return 0;
 907
 908 ok:
 909         rc = smb311_crypto_shash_allocate(server);
 910         if (rc)
 911                 return rc;
 912
 913         sha512 = server->secmech.sha512;
 914         rc = crypto_shash_init(sha512);
 915         if (rc) {
 916                 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
 917                 return rc;
 918         }
 919
 920         rc = crypto_shash_update(sha512, ses->preauth_sha_hash,
 921                                  SMB2_PREAUTH_HASH_SIZE);
 922         if (rc) {
 923                 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
 924                 return rc;
 925         }
 926
 927         for (i = 0; i < nvec; i++) {
 928                 rc = crypto_shash_update(sha512, iov[i].iov_base, iov[i].iov_len);
 929                 if (rc) {
 930                         cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
 931                                  __func__);
 932                         return rc;
 933                 }
 934         }
 935
 936         rc = crypto_shash_final(sha512, ses->preauth_sha_hash);
 937         if (rc) {
 938                 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
 939                          __func__);
 940                 return rc;
 941         }
 942
 943         return 0;
 944 }