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)
 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 smb2_hdr *shdr = (struct smb2_hdr *)buf;
 139         struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
 140         int hdr_size = sizeof(struct smb2_hdr);
 141         int pdu_size = sizeof(struct smb2_pdu);
 142         int command;
 143         __u32 calc_len; /* calculated length */
 144         __u64 mid;
 145
 146         /*
 147          * Add function to do table lookup of StructureSize by command
 148          * ie Validate the wct via smb2_struct_sizes table above
 149          */
 150         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 151                 struct smb2_transform_hdr *thdr =
 152                         (struct smb2_transform_hdr *)buf;
 153                 struct cifs_ses *ses = NULL;
 154                 struct cifs_ses *iter;
 155
 156                 /* decrypt frame now that it is completely read in */
 157                 spin_lock(&cifs_tcp_ses_lock);
 158                 list_for_each_entry(iter, &server->smb_ses_list, smb_ses_list) {
 159                         if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
 160                                 ses = iter;
 161                                 break;
 162                         }
 163                 }
 164                 spin_unlock(&cifs_tcp_ses_lock);
 165                 if (!ses) {
 166                         cifs_dbg(VFS, "no decryption - session id not found\n");
 167                         return 1;
 168                 }
 169         }
 170
 171         mid = le64_to_cpu(shdr->MessageId);
 172         if (len < pdu_size) {
 173                 if ((len >= hdr_size)
 174                     && (shdr->Status != 0)) {
 175                         pdu->StructureSize2 = 0;
 176                         /*
 177                          * As with SMB/CIFS, on some error cases servers may
 178                          * not return wct properly
 179                          */
 180                         return 0;
 181                 } else {
 182                         cifs_dbg(VFS, "Length less than SMB header size\n");
 183                 }
 184                 return 1;
 185         }
 186         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 187                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 188                          mid);
 189                 return 1;
 190         }
 191
 192         if (check_smb2_hdr(shdr, mid))
 193                 return 1;
 194
 195         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 196                 cifs_dbg(VFS, "Invalid structure size %u\n",
 197                          le16_to_cpu(shdr->StructureSize));
 198                 return 1;
 199         }
 200
 201         command = le16_to_cpu(shdr->Command);
 202         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 203                 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
 204                 return 1;
 205         }
 206
 207         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 208                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 209                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
 210                         /* error packets have 9 byte structure size */
 211                         cifs_dbg(VFS, "Invalid response size %u for command %d\n",
 212                                  le16_to_cpu(pdu->StructureSize2), command);
 213                         return 1;
 214                 } else if (command == SMB2_OPLOCK_BREAK_HE
 215                            && (shdr->Status == 0)
 216                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 217                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 218                         /* special case for SMB2.1 lease break message */
 219                         cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
 220                                  le16_to_cpu(pdu->StructureSize2));
 221                         return 1;
 222                 }
 223         }
 224
 225         calc_len = smb2_calc_size(buf);
 226
 227         /* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
 228          * be 0, and not a real miscalculation */
 229         if (command == SMB2_IOCTL_HE && calc_len == 0)
 230                 return 0;
 231
 232         if (command == SMB2_NEGOTIATE_HE)
 233                 calc_len += get_neg_ctxt_len(shdr, len, calc_len);
 234
 235         if (len != calc_len) {
 236                 /* create failed on symlink */
 237                 if (command == SMB2_CREATE_HE &&
 238                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 239                         return 0;
 240                 /* Windows 7 server returns 24 bytes more */
 241                 if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 242                         return 0;
 243                 /* server can return one byte more due to implied bcc[0] */
 244                 if (calc_len == len + 1)
 245                         return 0;
 246
 247                 /*
 248                  * Some windows servers (win2016) will pad also the final
 249                  * PDU in a compound to 8 bytes.
 250                  */
 251                 if (((calc_len + 7) & ~7) == len)
 252                         return 0;
 253
 254                 /*
 255                  * MacOS server pads after SMB2.1 write response with 3 bytes
 256                  * of junk. Other servers match RFC1001 len to actual
 257                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 258                  * Some windows servers also pad up to 8 bytes when compounding.
 259                  */
 260                 if (calc_len < len)
 261                         return 0;
 262
 263                 /* Only log a message if len was really miscalculated */
 264                 if (unlikely(cifsFYI))
 265                         cifs_dbg(FYI, "Server response too short: calculated "
 266                                  "length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
 267                                  calc_len, len, command, mid);
 268                 else
 269                         pr_warn("Server response too short: calculated length "
 270                                 "%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
 271                                 calc_len, len, command, mid);
 272
 273                 return 1;
 274         }
 275         return 0;
 276 }
 277
 278 /*
 279  * The size of the variable area depends on the offset and length fields
 280  * located in different fields for various SMB2 responses. SMB2 responses
 281  * with no variable length info, show an offset of zero for the offset field.
 282  */
 283 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 284         /* SMB2_NEGOTIATE */ true,
 285         /* SMB2_SESSION_SETUP */ true,
 286         /* SMB2_LOGOFF */ false,
 287         /* SMB2_TREE_CONNECT */ false,
 288         /* SMB2_TREE_DISCONNECT */ false,
 289         /* SMB2_CREATE */ true,
 290         /* SMB2_CLOSE */ false,
 291         /* SMB2_FLUSH */ false,
 292         /* SMB2_READ */ true,
 293         /* SMB2_WRITE */ false,
 294         /* SMB2_LOCK */ false,
 295         /* SMB2_IOCTL */ true,
 296         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 297         /* SMB2_ECHO */ false,
 298         /* SMB2_QUERY_DIRECTORY */ true,
 299         /* SMB2_CHANGE_NOTIFY */ true,
 300         /* SMB2_QUERY_INFO */ true,
 301         /* SMB2_SET_INFO */ false,
 302         /* SMB2_OPLOCK_BREAK */ false
 303 };
 304
 305 /*
 306  * Returns the pointer to the beginning of the data area. Length of the data
 307  * area and the offset to it (from the beginning of the smb are also returned.
 308  */
 309 char *
 310 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
 311 {
 312         *off = 0;
 313         *len = 0;
 314
 315         /* error responses do not have data area */
 316         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 317             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 318                                                 SMB2_ERROR_STRUCTURE_SIZE2_LE)
 319                 return NULL;
 320
 321         /*
 322          * Following commands have data areas so we have to get the location
 323          * of the data buffer offset and data buffer length for the particular
 324          * command.
 325          */
 326         switch (shdr->Command) {
 327         case SMB2_NEGOTIATE:
 328                 *off = le16_to_cpu(
 329                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 330                 *len = le16_to_cpu(
 331                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 332                 break;
 333         case SMB2_SESSION_SETUP:
 334                 *off = le16_to_cpu(
 335                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 336                 *len = le16_to_cpu(
 337                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 338                 break;
 339         case SMB2_CREATE:
 340                 *off = le32_to_cpu(
 341                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 342                 *len = le32_to_cpu(
 343                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 344                 break;
 345         case SMB2_QUERY_INFO:
 346                 *off = le16_to_cpu(
 347                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 348                 *len = le32_to_cpu(
 349                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 350                 break;
 351         case SMB2_READ:
 352                 /* TODO: is this a bug ? */
 353                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 354                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 355                 break;
 356         case SMB2_QUERY_DIRECTORY:
 357                 *off = le16_to_cpu(
 358                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 359                 *len = le32_to_cpu(
 360                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 361                 break;
 362         case SMB2_IOCTL:
 363                 *off = le32_to_cpu(
 364                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 365                 *len = le32_to_cpu(
 366                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 367                 break;
 368         case SMB2_CHANGE_NOTIFY:
 369                 *off = le16_to_cpu(
 370                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
 371                 *len = le32_to_cpu(
 372                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
 373                 break;
 374         default:
 375                 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
 376                 break;
 377         }
 378
 379         /*
 380          * Invalid length or offset probably means data area is invalid, but
 381          * we have little choice but to ignore the data area in this case.
 382          */
 383         if (*off > 4096) {
 384                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 385                 *len = 0;
 386                 *off = 0;
 387         } else if (*off < 0) {
 388                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 389                          *off);
 390                 *off = 0;
 391                 *len = 0;
 392         } else if (*len < 0) {
 393                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 394                          *len);
 395                 *len = 0;
 396         } else if (*len > 128 * 1024) {
 397                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 398                 *len = 0;
 399         }
 400
 401         /* return pointer to beginning of data area, ie offset from SMB start */
 402         if ((*off != 0) && (*len != 0))
 403                 return (char *)shdr + *off;
 404         else
 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
 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 *
 456 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 457 {
 458         int len;
 459         const char *start_of_path;
 460         __le16 *to;
 461         int map_type;
 462
 463         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 464                 map_type = SFM_MAP_UNI_RSVD;
 465         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 466                 map_type = SFU_MAP_UNI_RSVD;
 467         else
 468                 map_type = NO_MAP_UNI_RSVD;
 469
 470         /* Windows doesn't allow paths beginning with \ */
 471         if (from[0] == '\\')
 472                 start_of_path = from + 1;
 473
 474         /* SMB311 POSIX extensions paths do not include leading slash */
 475         else if (cifs_sb_master_tlink(cifs_sb) &&
 476                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 477                  (from[0] == '/')) {
 478                 start_of_path = from + 1;
 479         } else
 480                 start_of_path = from;
 481
 482         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 483                                    cifs_sb->local_nls, map_type);
 484         return to;
 485 }
 486
 487 __le32
 488 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 489 {
 490         __le32 lease = 0;
 491
 492         if (CIFS_CACHE_WRITE(cinode))
 493                 lease |= SMB2_LEASE_WRITE_CACHING_LE;
 494         if (CIFS_CACHE_HANDLE(cinode))
 495                 lease |= SMB2_LEASE_HANDLE_CACHING_LE;
 496         if (CIFS_CACHE_READ(cinode))
 497                 lease |= SMB2_LEASE_READ_CACHING_LE;
 498         return lease;
 499 }
 500
 501 struct smb2_lease_break_work {
 502         struct work_struct lease_break;
 503         struct tcon_link *tlink;
 504         __u8 lease_key[16];
 505         __le32 lease_state;
 506 };
 507
 508 static void
 509 cifs_ses_oplock_break(struct work_struct *work)
 510 {
 511         struct smb2_lease_break_work *lw = container_of(work,
 512                                 struct smb2_lease_break_work, lease_break);
 513         int rc = 0;
 514
 515         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 516                               lw->lease_state);
 517
 518         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 519         cifs_put_tlink(lw->tlink);
 520         kfree(lw);
 521 }
 522
 523 static void
 524 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
 525                               __le32 new_lease_state)
 526 {
 527         struct smb2_lease_break_work *lw;
 528
 529         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 530         if (!lw) {
 531                 cifs_put_tlink(tlink);
 532                 return;
 533         }
 534
 535         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 536         lw->tlink = tlink;
 537         lw->lease_state = new_lease_state;
 538         memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
 539         queue_work(cifsiod_wq, &lw->lease_break);
 540 }
 541
 542 static bool
 543 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 544 {
 545         __u8 lease_state;
 546         struct cifsFileInfo *cfile;
 547         struct cifsInodeInfo *cinode;
 548         int ack_req = le32_to_cpu(rsp->Flags &
 549                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 550
 551         lease_state = le32_to_cpu(rsp->NewLeaseState);
 552
 553         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 554                 cinode = CIFS_I(d_inode(cfile->dentry));
 555
 556                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 557                                                         SMB2_LEASE_KEY_SIZE))
 558                         continue;
 559
 560                 cifs_dbg(FYI, "found in the open list\n");
 561                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 562                          lease_state);
 563
 564                 if (ack_req)
 565                         cfile->oplock_break_cancelled = false;
 566                 else
 567                         cfile->oplock_break_cancelled = true;
 568
 569                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 570
 571                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 572                 cfile->oplock_level = lease_state;
 573
 574                 cifs_queue_oplock_break(cfile);
 575                 return true;
 576         }
 577
 578         return false;
 579 }
 580
 581 static struct cifs_pending_open *
 582 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
 583                                   struct smb2_lease_break *rsp)
 584 {
 585         __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
 586         int ack_req = le32_to_cpu(rsp->Flags &
 587                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 588         struct cifs_pending_open *open;
 589         struct cifs_pending_open *found = NULL;
 590
 591         list_for_each_entry(open, &tcon->pending_opens, olist) {
 592                 if (memcmp(open->lease_key, rsp->LeaseKey,
 593                            SMB2_LEASE_KEY_SIZE))
 594                         continue;
 595
 596                 if (!found && ack_req) {
 597                         found = open;
 598                 }
 599
 600                 cifs_dbg(FYI, "found in the pending open list\n");
 601                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 602                          lease_state);
 603
 604                 open->oplock = lease_state;
 605         }
 606
 607         return found;
 608 }
 609
 610 static bool
 611 smb2_is_valid_lease_break(char *buffer)
 612 {
 613         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 614         struct TCP_Server_Info *server;
 615         struct cifs_ses *ses;
 616         struct cifs_tcon *tcon;
 617         struct cifs_pending_open *open;
 618
 619         cifs_dbg(FYI, "Checking for lease break\n");
 620
 621         /* look up tcon based on tid & uid */
 622         spin_lock(&cifs_tcp_ses_lock);
 623         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
 624                 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
 625                         list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 626                                 spin_lock(&tcon->open_file_lock);
 627                                 cifs_stats_inc(
 628                                     &tcon->stats.cifs_stats.num_oplock_brks);
 629                                 if (smb2_tcon_has_lease(tcon, rsp)) {
 630                                         spin_unlock(&tcon->open_file_lock);
 631                                         spin_unlock(&cifs_tcp_ses_lock);
 632                                         return true;
 633                                 }
 634                                 open = smb2_tcon_find_pending_open_lease(tcon,
 635                                                                          rsp);
 636                                 if (open) {
 637                                         __u8 lease_key[SMB2_LEASE_KEY_SIZE];
 638                                         struct tcon_link *tlink;
 639
 640                                         tlink = cifs_get_tlink(open->tlink);
 641                                         memcpy(lease_key, open->lease_key,
 642                                                SMB2_LEASE_KEY_SIZE);
 643                                         spin_unlock(&tcon->open_file_lock);
 644                                         spin_unlock(&cifs_tcp_ses_lock);
 645                                         smb2_queue_pending_open_break(tlink,
 646                                                                       lease_key,
 647                                                                       rsp->NewLeaseState);
 648                                         return true;
 649                                 }
 650                                 spin_unlock(&tcon->open_file_lock);
 651
 652                                 if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
 653                                         spin_unlock(&cifs_tcp_ses_lock);
 654                                         return true;
 655                                 }
 656                         }
 657                 }
 658         }
 659         spin_unlock(&cifs_tcp_ses_lock);
 660         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 661         trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
 662                                    le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
 663                                    le64_to_cpu(rsp->hdr.SessionId),
 664                                    *((u64 *)rsp->LeaseKey),
 665                                    *((u64 *)&rsp->LeaseKey[8]));
 666
 667         return false;
 668 }
 669
 670 bool
 671 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 672 {
 673         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 674         struct cifs_ses *ses;
 675         struct cifs_tcon *tcon;
 676         struct cifsInodeInfo *cinode;
 677         struct cifsFileInfo *cfile;
 678
 679         cifs_dbg(FYI, "Checking for oplock break\n");
 680
 681         if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
 682                 return false;
 683
 684         if (rsp->StructureSize !=
 685                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 686                 if (le16_to_cpu(rsp->StructureSize) == 44)
 687                         return smb2_is_valid_lease_break(buffer);
 688                 else
 689                         return false;
 690         }
 691
 692         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 693
 694         /* look up tcon based on tid & uid */
 695         spin_lock(&cifs_tcp_ses_lock);
 696         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
 697                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 698
 699                         spin_lock(&tcon->open_file_lock);
 700                         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 701                                 if (rsp->PersistentFid !=
 702                                     cfile->fid.persistent_fid ||
 703                                     rsp->VolatileFid !=
 704                                     cfile->fid.volatile_fid)
 705                                         continue;
 706
 707                                 cifs_dbg(FYI, "file id match, oplock break\n");
 708                                 cifs_stats_inc(
 709                                     &tcon->stats.cifs_stats.num_oplock_brks);
 710                                 cinode = CIFS_I(d_inode(cfile->dentry));
 711                                 spin_lock(&cfile->file_info_lock);
 712                                 if (!CIFS_CACHE_WRITE(cinode) &&
 713                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 714                                         cfile->oplock_break_cancelled = true;
 715                                 else
 716                                         cfile->oplock_break_cancelled = false;
 717
 718                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 719                                         &cinode->flags);
 720
 721                                 cfile->oplock_epoch = 0;
 722                                 cfile->oplock_level = rsp->OplockLevel;
 723
 724                                 spin_unlock(&cfile->file_info_lock);
 725
 726                                 cifs_queue_oplock_break(cfile);
 727
 728                                 spin_unlock(&tcon->open_file_lock);
 729                                 spin_unlock(&cifs_tcp_ses_lock);
 730                                 return true;
 731                         }
 732                         spin_unlock(&tcon->open_file_lock);
 733                 }
 734         }
 735         spin_unlock(&cifs_tcp_ses_lock);
 736         cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
 737         trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
 738                                   le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
 739                                   le64_to_cpu(rsp->hdr.SessionId));
 740
 741         return true;
 742 }
 743
 744 void
 745 smb2_cancelled_close_fid(struct work_struct *work)
 746 {
 747         struct close_cancelled_open *cancelled = container_of(work,
 748                                         struct close_cancelled_open, work);
 749         struct cifs_tcon *tcon = cancelled->tcon;
 750         int rc;
 751
 752         if (cancelled->mid)
 753                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
 754                               cancelled->mid);
 755         else
 756                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
 757
 758         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
 759                         cancelled->fid.volatile_fid);
 760         if (rc)
 761                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 762
 763         cifs_put_tcon(tcon);
 764         kfree(cancelled);
 765 }
 766
 767 /*
 768  * Caller should already has an extra reference to @tcon
 769  * This function is used to queue work to close a handle to prevent leaks
 770  * on the server.
 771  * We handle two cases. If an open was interrupted after we sent the
 772  * SMB2_CREATE to the server but before we processed the reply, and second
 773  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
 774  */
 775 static int
 776 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 777                             __u64 persistent_fid, __u64 volatile_fid)
 778 {
 779         struct close_cancelled_open *cancelled;
 780
 781         cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
 782         if (!cancelled)
 783                 return -ENOMEM;
 784
 785         cancelled->fid.persistent_fid = persistent_fid;
 786         cancelled->fid.volatile_fid = volatile_fid;
 787         cancelled->tcon = tcon;
 788         cancelled->cmd = cmd;
 789         cancelled->mid = mid;
 790         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 791         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
 792
 793         return 0;
 794 }
 795
 796 int
 797 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 798                             __u64 volatile_fid)
 799 {
 800         int rc;
 801
 802         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 803         spin_lock(&cifs_tcp_ses_lock);
 804         if (tcon->tc_count <= 0) {
 805                 struct TCP_Server_Info *server = NULL;
 806
 807                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 808                 spin_unlock(&cifs_tcp_ses_lock);
 809
 810                 if (tcon->ses)
 811                         server = tcon->ses->server;
 812
 813                 cifs_server_dbg(FYI, "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
 814                                 tcon->tid, persistent_fid, volatile_fid);
 815
 816                 return 0;
 817         }
 818         tcon->tc_count++;
 819         spin_unlock(&cifs_tcp_ses_lock);
 820
 821         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 822                                          persistent_fid, volatile_fid);
 823         if (rc)
 824                 cifs_put_tcon(tcon);
 825
 826         return rc;
 827 }
 828
 829 int
 830 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 831 {
 832         struct smb2_hdr *hdr = mid->resp_buf;
 833         struct smb2_create_rsp *rsp = mid->resp_buf;
 834         struct cifs_tcon *tcon;
 835         int rc;
 836
 837         if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
 838             hdr->Status != STATUS_SUCCESS)
 839                 return 0;
 840
 841         tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
 842                                   le32_to_cpu(hdr->Id.SyncId.TreeId));
 843         if (!tcon)
 844                 return -ENOENT;
 845
 846         rc = __smb2_handle_cancelled_cmd(tcon,
 847                                          le16_to_cpu(hdr->Command),
 848                                          le64_to_cpu(hdr->MessageId),
 849                                          rsp->PersistentFileId,
 850                                          rsp->VolatileFileId);
 851         if (rc)
 852                 cifs_put_tcon(tcon);
 853
 854         return rc;
 855 }
 856
 857 /**
 858  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 859  *
 860  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 861  * SMB2 header.
 862  *
 863  * @ses:        server session structure
 864  * @server:     pointer to server info
 865  * @iov:        array containing the SMB request we will send to the server
 866  * @nvec:       number of array entries for the iov
 867  */
 868 int
 869 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
 870                            struct kvec *iov, int nvec)
 871 {
 872         int i, rc;
 873         struct sdesc *d;
 874         struct smb2_hdr *hdr;
 875
 876         hdr = (struct smb2_hdr *)iov[0].iov_base;
 877         /* neg prot are always taken */
 878         if (hdr->Command == SMB2_NEGOTIATE)
 879                 goto ok;
 880
 881         /*
 882          * If we process a command which wasn't a negprot it means the
 883          * neg prot was already done, so the server dialect was set
 884          * and we can test it. Preauth requires 3.1.1 for now.
 885          */
 886         if (server->dialect != SMB311_PROT_ID)
 887                 return 0;
 888
 889         if (hdr->Command != SMB2_SESSION_SETUP)
 890                 return 0;
 891
 892         /* skip last sess setup response */
 893         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 894             && (hdr->Status == NT_STATUS_OK
 895                 || (hdr->Status !=
 896                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
 897                 return 0;
 898
 899 ok:
 900         rc = smb311_crypto_shash_allocate(server);
 901         if (rc)
 902                 return rc;
 903
 904         d = server->secmech.sdescsha512;
 905         rc = crypto_shash_init(&d->shash);
 906         if (rc) {
 907                 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
 908                 return rc;
 909         }
 910
 911         rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
 912                                  SMB2_PREAUTH_HASH_SIZE);
 913         if (rc) {
 914                 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
 915                 return rc;
 916         }
 917
 918         for (i = 0; i < nvec; i++) {
 919                 rc = crypto_shash_update(&d->shash,
 920                                          iov[i].iov_base, iov[i].iov_len);
 921                 if (rc) {
 922                         cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
 923                                  __func__);
 924                         return rc;
 925                 }
 926         }
 927
 928         rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
 929         if (rc) {
 930                 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
 931                          __func__);
 932                 return rc;
 933         }
 934
 935         return 0;
 936 }