fs/cifs/smb2misc.c

   1 /*
   2  *   fs/cifs/smb2misc.c
   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  *   This library is free software; you can redistribute it and/or modify
  10  *   it under the terms of the GNU Lesser General Public License as published
  11  *   by the Free Software Foundation; either version 2.1 of the License, or
  12  *   (at your option) any later version.
  13  *
  14  *   This library is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  17  *   the GNU Lesser General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU Lesser General Public License
  20  *   along with this library; if not, write to the Free Software
  21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23 #include <linux/ctype.h>
  24 #include "smb2pdu.h"
  25 #include "cifsglob.h"
  26 #include "cifsproto.h"
  27 #include "smb2proto.h"
  28 #include "cifs_debug.h"
  29 #include "cifs_unicode.h"
  30 #include "smb2status.h"
  31 #include "smb2glob.h"
  32 #include "nterr.h"
  33
  34 static int
  35 check_smb2_hdr(struct smb2_sync_hdr *shdr, __u64 mid)
  36 {
  37         __u64 wire_mid = le64_to_cpu(shdr->MessageId);
  38
  39         /*
  40          * Make sure that this really is an SMB, that it is a response,
  41          * and that the message ids match.
  42          */
  43         if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
  44             (mid == wire_mid)) {
  45                 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
  46                         return 0;
  47                 else {
  48                         /* only one valid case where server sends us request */
  49                         if (shdr->Command == SMB2_OPLOCK_BREAK)
  50                                 return 0;
  51                         else
  52                                 cifs_dbg(VFS, "Received Request not response\n");
  53                 }
  54         } else { /* bad signature or mid */
  55                 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
  56                         cifs_dbg(VFS, "Bad protocol string signature header %x\n",
  57                                  le32_to_cpu(shdr->ProtocolId));
  58                 if (mid != wire_mid)
  59                         cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
  60                                  mid, wire_mid);
  61         }
  62         cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
  63         return 1;
  64 }
  65
  66 /*
  67  *  The following table defines the expected "StructureSize" of SMB2 responses
  68  *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
  69  *
  70  *  Note that commands are defined in smb2pdu.h in le16 but the array below is
  71  *  indexed by command in host byte order
  72  */
  73 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
  74         /* SMB2_NEGOTIATE */ cpu_to_le16(65),
  75         /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
  76         /* SMB2_LOGOFF */ cpu_to_le16(4),
  77         /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
  78         /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
  79         /* SMB2_CREATE */ cpu_to_le16(89),
  80         /* SMB2_CLOSE */ cpu_to_le16(60),
  81         /* SMB2_FLUSH */ cpu_to_le16(4),
  82         /* SMB2_READ */ cpu_to_le16(17),
  83         /* SMB2_WRITE */ cpu_to_le16(17),
  84         /* SMB2_LOCK */ cpu_to_le16(4),
  85         /* SMB2_IOCTL */ cpu_to_le16(49),
  86         /* BB CHECK this ... not listed in documentation */
  87         /* SMB2_CANCEL */ cpu_to_le16(0),
  88         /* SMB2_ECHO */ cpu_to_le16(4),
  89         /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
  90         /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
  91         /* SMB2_QUERY_INFO */ cpu_to_le16(9),
  92         /* SMB2_SET_INFO */ cpu_to_le16(2),
  93         /* BB FIXME can also be 44 for lease break */
  94         /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
  95 };
  96
  97 static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
  98                               __u32 non_ctxlen)
  99 {
 100         __u16 neg_count;
 101         __u32 nc_offset, size_of_pad_before_neg_ctxts;
 102         struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
 103
 104         /* Negotiate contexts are only valid for latest dialect SMB3.11 */
 105         neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
 106         if ((neg_count == 0) ||
 107            (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
 108                 return 0;
 109
 110         /* Make sure that negotiate contexts start after gss security blob */
 111         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
 112         if (nc_offset < non_ctxlen) {
 113                 printk_once(KERN_WARNING "invalid negotiate context offset\n");
 114                 return 0;
 115         }
 116         size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 117
 118         /* Verify that at least minimal negotiate contexts fit within frame */
 119         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
 120                 printk_once(KERN_WARNING "negotiate context goes beyond end\n");
 121                 return 0;
 122         }
 123
 124         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
 125                 len - nc_offset, size_of_pad_before_neg_ctxts);
 126
 127         /* length of negcontexts including pad from end of sec blob to them */
 128         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
 129 }
 130
 131 int
 132 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 133 {
 134         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
 135         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
 136         __u64 mid;
 137         __u32 clc_len;  /* calculated length */
 138         int command;
 139         int pdu_size = sizeof(struct smb2_sync_pdu);
 140         int hdr_size = sizeof(struct smb2_sync_hdr);
 141
 142         /*
 143          * Add function to do table lookup of StructureSize by command
 144          * ie Validate the wct via smb2_struct_sizes table above
 145          */
 146         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 147                 struct smb2_transform_hdr *thdr =
 148                         (struct smb2_transform_hdr *)buf;
 149                 struct cifs_ses *ses = NULL;
 150                 struct list_head *tmp;
 151
 152                 /* decrypt frame now that it is completely read in */
 153                 spin_lock(&cifs_tcp_ses_lock);
 154                 list_for_each(tmp, &srvr->smb_ses_list) {
 155                         ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 156                         if (ses->Suid == thdr->SessionId)
 157                                 break;
 158
 159                         ses = NULL;
 160                 }
 161                 spin_unlock(&cifs_tcp_ses_lock);
 162                 if (ses == NULL) {
 163                         cifs_dbg(VFS, "no decryption - session id not found\n");
 164                         return 1;
 165                 }
 166         }
 167
 168         mid = le64_to_cpu(shdr->MessageId);
 169         if (len < pdu_size) {
 170                 if ((len >= hdr_size)
 171                     && (shdr->Status != 0)) {
 172                         pdu->StructureSize2 = 0;
 173                         /*
 174                          * As with SMB/CIFS, on some error cases servers may
 175                          * not return wct properly
 176                          */
 177                         return 0;
 178                 } else {
 179                         cifs_dbg(VFS, "Length less than SMB header size\n");
 180                 }
 181                 return 1;
 182         }
 183         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 184                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 185                          mid);
 186                 return 1;
 187         }
 188
 189         if (check_smb2_hdr(shdr, mid))
 190                 return 1;
 191
 192         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 193                 cifs_dbg(VFS, "Illegal structure size %u\n",
 194                          le16_to_cpu(shdr->StructureSize));
 195                 return 1;
 196         }
 197
 198         command = le16_to_cpu(shdr->Command);
 199         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 200                 cifs_dbg(VFS, "Illegal SMB2 command %d\n", command);
 201                 return 1;
 202         }
 203
 204         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 205                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 206                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
 207                         /* error packets have 9 byte structure size */
 208                         cifs_dbg(VFS, "Illegal response size %u for command %d\n",
 209                                  le16_to_cpu(pdu->StructureSize2), command);
 210                         return 1;
 211                 } else if (command == SMB2_OPLOCK_BREAK_HE
 212                            && (shdr->Status == 0)
 213                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 214                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 215                         /* special case for SMB2.1 lease break message */
 216                         cifs_dbg(VFS, "Illegal response size %d for oplock break\n",
 217                                  le16_to_cpu(pdu->StructureSize2));
 218                         return 1;
 219                 }
 220         }
 221
 222         clc_len = smb2_calc_size(buf, srvr);
 223
 224         if (shdr->Command == SMB2_NEGOTIATE)
 225                 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
 226
 227         if (len != clc_len) {
 228                 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
 229                          clc_len, len, mid);
 230                 /* create failed on symlink */
 231                 if (command == SMB2_CREATE_HE &&
 232                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 233                         return 0;
 234                 /* Windows 7 server returns 24 bytes more */
 235                 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 236                         return 0;
 237                 /* server can return one byte more due to implied bcc[0] */
 238                 if (clc_len == len + 1)
 239                         return 0;
 240
 241                 /*
 242                  * Some windows servers (win2016) will pad also the final
 243                  * PDU in a compound to 8 bytes.
 244                  */
 245                 if (((clc_len + 7) & ~7) == len)
 246                         return 0;
 247
 248                 /*
 249                  * MacOS server pads after SMB2.1 write response with 3 bytes
 250                  * of junk. Other servers match RFC1001 len to actual
 251                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 252                  * Some windows servers also pad up to 8 bytes when compounding.
 253                  */
 254                 if (clc_len < len)
 255                         return 0;
 256
 257                 pr_warn_once(
 258                         "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
 259                         len, clc_len, command, mid);
 260
 261                 return 1;
 262         }
 263         return 0;
 264 }
 265
 266 /*
 267  * The size of the variable area depends on the offset and length fields
 268  * located in different fields for various SMB2 responses. SMB2 responses
 269  * with no variable length info, show an offset of zero for the offset field.
 270  */
 271 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 272         /* SMB2_NEGOTIATE */ true,
 273         /* SMB2_SESSION_SETUP */ true,
 274         /* SMB2_LOGOFF */ false,
 275         /* SMB2_TREE_CONNECT */ false,
 276         /* SMB2_TREE_DISCONNECT */ false,
 277         /* SMB2_CREATE */ true,
 278         /* SMB2_CLOSE */ false,
 279         /* SMB2_FLUSH */ false,
 280         /* SMB2_READ */ true,
 281         /* SMB2_WRITE */ false,
 282         /* SMB2_LOCK */ false,
 283         /* SMB2_IOCTL */ true,
 284         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 285         /* SMB2_ECHO */ false,
 286         /* SMB2_QUERY_DIRECTORY */ true,
 287         /* SMB2_CHANGE_NOTIFY */ true,
 288         /* SMB2_QUERY_INFO */ true,
 289         /* SMB2_SET_INFO */ false,
 290         /* SMB2_OPLOCK_BREAK */ false
 291 };
 292
 293 /*
 294  * Returns the pointer to the beginning of the data area. Length of the data
 295  * area and the offset to it (from the beginning of the smb are also returned.
 296  */
 297 char *
 298 smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
 299 {
 300         *off = 0;
 301         *len = 0;
 302
 303         /* error responses do not have data area */
 304         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 305             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 306                                                 SMB2_ERROR_STRUCTURE_SIZE2)
 307                 return NULL;
 308
 309         /*
 310          * Following commands have data areas so we have to get the location
 311          * of the data buffer offset and data buffer length for the particular
 312          * command.
 313          */
 314         switch (shdr->Command) {
 315         case SMB2_NEGOTIATE:
 316                 *off = le16_to_cpu(
 317                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 318                 *len = le16_to_cpu(
 319                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 320                 break;
 321         case SMB2_SESSION_SETUP:
 322                 *off = le16_to_cpu(
 323                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 324                 *len = le16_to_cpu(
 325                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 326                 break;
 327         case SMB2_CREATE:
 328                 *off = le32_to_cpu(
 329                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 330                 *len = le32_to_cpu(
 331                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 332                 break;
 333         case SMB2_QUERY_INFO:
 334                 *off = le16_to_cpu(
 335                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 336                 *len = le32_to_cpu(
 337                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 338                 break;
 339         case SMB2_READ:
 340                 /* TODO: is this a bug ? */
 341                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 342                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 343                 break;
 344         case SMB2_QUERY_DIRECTORY:
 345                 *off = le16_to_cpu(
 346                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 347                 *len = le32_to_cpu(
 348                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 349                 break;
 350         case SMB2_IOCTL:
 351                 *off = le32_to_cpu(
 352                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 353                 *len = le32_to_cpu(
 354                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 355                 break;
 356         case SMB2_CHANGE_NOTIFY:
 357         default:
 358                 /* BB FIXME for unimplemented cases above */
 359                 cifs_dbg(VFS, "no length check for command\n");
 360                 break;
 361         }
 362
 363         /*
 364          * Invalid length or offset probably means data area is invalid, but
 365          * we have little choice but to ignore the data area in this case.
 366          */
 367         if (*off > 4096) {
 368                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 369                 *len = 0;
 370                 *off = 0;
 371         } else if (*off < 0) {
 372                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 373                          *off);
 374                 *off = 0;
 375                 *len = 0;
 376         } else if (*len < 0) {
 377                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 378                          *len);
 379                 *len = 0;
 380         } else if (*len > 128 * 1024) {
 381                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 382                 *len = 0;
 383         }
 384
 385         /* return pointer to beginning of data area, ie offset from SMB start */
 386         if ((*off != 0) && (*len != 0))
 387                 return (char *)shdr + *off;
 388         else
 389                 return NULL;
 390 }
 391
 392 /*
 393  * Calculate the size of the SMB message based on the fixed header
 394  * portion, the number of word parameters and the data portion of the message.
 395  */
 396 unsigned int
 397 smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 398 {
 399         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
 400         struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
 401         int offset; /* the offset from the beginning of SMB to data area */
 402         int data_length; /* the length of the variable length data area */
 403         /* Structure Size has already been checked to make sure it is 64 */
 404         int len = le16_to_cpu(shdr->StructureSize);
 405
 406         /*
 407          * StructureSize2, ie length of fixed parameter area has already
 408          * been checked to make sure it is the correct length.
 409          */
 410         len += le16_to_cpu(pdu->StructureSize2);
 411
 412         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 413                 goto calc_size_exit;
 414
 415         smb2_get_data_area_len(&offset, &data_length, shdr);
 416         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 417
 418         if (data_length > 0) {
 419                 /*
 420                  * Check to make sure that data area begins after fixed area,
 421                  * Note that last byte of the fixed area is part of data area
 422                  * for some commands, typically those with odd StructureSize,
 423                  * so we must add one to the calculation.
 424                  */
 425                 if (offset + 1 < len) {
 426                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
 427                                  offset + 1, len);
 428                         data_length = 0;
 429                 } else {
 430                         len = offset + data_length;
 431                 }
 432         }
 433 calc_size_exit:
 434         cifs_dbg(FYI, "SMB2 len %d\n", len);
 435         return len;
 436 }
 437
 438 /* Note: caller must free return buffer */
 439 __le16 *
 440 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 441 {
 442         int len;
 443         const char *start_of_path;
 444         __le16 *to;
 445         int map_type;
 446
 447         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 448                 map_type = SFM_MAP_UNI_RSVD;
 449         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 450                 map_type = SFU_MAP_UNI_RSVD;
 451         else
 452                 map_type = NO_MAP_UNI_RSVD;
 453
 454         /* Windows doesn't allow paths beginning with \ */
 455         if (from[0] == '\\')
 456                 start_of_path = from + 1;
 457
 458         /* SMB311 POSIX extensions paths do not include leading slash */
 459         else if (cifs_sb_master_tlink(cifs_sb) &&
 460                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 461                  (from[0] == '/')) {
 462                 start_of_path = from + 1;
 463         } else
 464                 start_of_path = from;
 465
 466         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 467                                    cifs_sb->local_nls, map_type);
 468         return to;
 469 }
 470
 471 __le32
 472 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 473 {
 474         __le32 lease = 0;
 475
 476         if (CIFS_CACHE_WRITE(cinode))
 477                 lease |= SMB2_LEASE_WRITE_CACHING;
 478         if (CIFS_CACHE_HANDLE(cinode))
 479                 lease |= SMB2_LEASE_HANDLE_CACHING;
 480         if (CIFS_CACHE_READ(cinode))
 481                 lease |= SMB2_LEASE_READ_CACHING;
 482         return lease;
 483 }
 484
 485 struct smb2_lease_break_work {
 486         struct work_struct lease_break;
 487         struct tcon_link *tlink;
 488         __u8 lease_key[16];
 489         __le32 lease_state;
 490 };
 491
 492 static void
 493 cifs_ses_oplock_break(struct work_struct *work)
 494 {
 495         struct smb2_lease_break_work *lw = container_of(work,
 496                                 struct smb2_lease_break_work, lease_break);
 497         int rc = 0;
 498
 499         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 500                               lw->lease_state);
 501
 502         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 503         cifs_put_tlink(lw->tlink);
 504         kfree(lw);
 505 }
 506
 507 static bool
 508 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
 509                     struct smb2_lease_break_work *lw)
 510 {
 511         bool found;
 512         __u8 lease_state;
 513         struct list_head *tmp;
 514         struct cifsFileInfo *cfile;
 515         struct cifs_pending_open *open;
 516         struct cifsInodeInfo *cinode;
 517         int ack_req = le32_to_cpu(rsp->Flags &
 518                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 519
 520         lease_state = le32_to_cpu(rsp->NewLeaseState);
 521
 522         list_for_each(tmp, &tcon->openFileList) {
 523                 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
 524                 cinode = CIFS_I(d_inode(cfile->dentry));
 525
 526                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 527                                                         SMB2_LEASE_KEY_SIZE))
 528                         continue;
 529
 530                 cifs_dbg(FYI, "found in the open list\n");
 531                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 532                          lease_state);
 533
 534                 if (ack_req)
 535                         cfile->oplock_break_cancelled = false;
 536                 else
 537                         cfile->oplock_break_cancelled = true;
 538
 539                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 540
 541                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 542                 cfile->oplock_level = lease_state;
 543
 544                 cifs_queue_oplock_break(cfile);
 545                 kfree(lw);
 546                 return true;
 547         }
 548
 549         found = false;
 550         list_for_each_entry(open, &tcon->pending_opens, olist) {
 551                 if (memcmp(open->lease_key, rsp->LeaseKey,
 552                            SMB2_LEASE_KEY_SIZE))
 553                         continue;
 554
 555                 if (!found && ack_req) {
 556                         found = true;
 557                         memcpy(lw->lease_key, open->lease_key,
 558                                SMB2_LEASE_KEY_SIZE);
 559                         lw->tlink = cifs_get_tlink(open->tlink);
 560                         queue_work(cifsiod_wq, &lw->lease_break);
 561                 }
 562
 563                 cifs_dbg(FYI, "found in the pending open list\n");
 564                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 565                          lease_state);
 566
 567                 open->oplock = lease_state;
 568         }
 569
 570         return found;
 571 }
 572
 573 static bool
 574 smb2_is_valid_lease_break(char *buffer)
 575 {
 576         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 577         struct list_head *tmp, *tmp1, *tmp2;
 578         struct TCP_Server_Info *server;
 579         struct cifs_ses *ses;
 580         struct cifs_tcon *tcon;
 581         struct smb2_lease_break_work *lw;
 582
 583         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 584         if (!lw)
 585                 return false;
 586
 587         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 588         lw->lease_state = rsp->NewLeaseState;
 589
 590         cifs_dbg(FYI, "Checking for lease break\n");
 591
 592         /* look up tcon based on tid & uid */
 593         spin_lock(&cifs_tcp_ses_lock);
 594         list_for_each(tmp, &cifs_tcp_ses_list) {
 595                 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 596
 597                 list_for_each(tmp1, &server->smb_ses_list) {
 598                         ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 599
 600                         list_for_each(tmp2, &ses->tcon_list) {
 601                                 tcon = list_entry(tmp2, struct cifs_tcon,
 602                                                   tcon_list);
 603                                 spin_lock(&tcon->open_file_lock);
 604                                 cifs_stats_inc(
 605                                     &tcon->stats.cifs_stats.num_oplock_brks);
 606                                 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
 607                                         spin_unlock(&tcon->open_file_lock);
 608                                         spin_unlock(&cifs_tcp_ses_lock);
 609                                         return true;
 610                                 }
 611                                 spin_unlock(&tcon->open_file_lock);
 612
 613                                 if (tcon->crfid.is_valid &&
 614                                     !memcmp(rsp->LeaseKey,
 615                                             tcon->crfid.fid->lease_key,
 616                                             SMB2_LEASE_KEY_SIZE)) {
 617                                         INIT_WORK(&tcon->crfid.lease_break,
 618                                                   smb2_cached_lease_break);
 619                                         queue_work(cifsiod_wq,
 620                                                    &tcon->crfid.lease_break);
 621                                         spin_unlock(&cifs_tcp_ses_lock);
 622                                         return true;
 623                                 }
 624                         }
 625                 }
 626         }
 627         spin_unlock(&cifs_tcp_ses_lock);
 628         kfree(lw);
 629         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 630         return false;
 631 }
 632
 633 bool
 634 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 635 {
 636         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 637         struct list_head *tmp, *tmp1, *tmp2;
 638         struct cifs_ses *ses;
 639         struct cifs_tcon *tcon;
 640         struct cifsInodeInfo *cinode;
 641         struct cifsFileInfo *cfile;
 642
 643         cifs_dbg(FYI, "Checking for oplock break\n");
 644
 645         if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
 646                 return false;
 647
 648         if (rsp->StructureSize !=
 649                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 650                 if (le16_to_cpu(rsp->StructureSize) == 44)
 651                         return smb2_is_valid_lease_break(buffer);
 652                 else
 653                         return false;
 654         }
 655
 656         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 657
 658         /* look up tcon based on tid & uid */
 659         spin_lock(&cifs_tcp_ses_lock);
 660         list_for_each(tmp, &server->smb_ses_list) {
 661                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 662
 663                 list_for_each(tmp1, &ses->tcon_list) {
 664                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
 665
 666                         spin_lock(&tcon->open_file_lock);
 667                         list_for_each(tmp2, &tcon->openFileList) {
 668                                 cfile = list_entry(tmp2, struct cifsFileInfo,
 669                                                      tlist);
 670                                 if (rsp->PersistentFid !=
 671                                     cfile->fid.persistent_fid ||
 672                                     rsp->VolatileFid !=
 673                                     cfile->fid.volatile_fid)
 674                                         continue;
 675
 676                                 cifs_dbg(FYI, "file id match, oplock break\n");
 677                                 cifs_stats_inc(
 678                                     &tcon->stats.cifs_stats.num_oplock_brks);
 679                                 cinode = CIFS_I(d_inode(cfile->dentry));
 680                                 spin_lock(&cfile->file_info_lock);
 681                                 if (!CIFS_CACHE_WRITE(cinode) &&
 682                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 683                                         cfile->oplock_break_cancelled = true;
 684                                 else
 685                                         cfile->oplock_break_cancelled = false;
 686
 687                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 688                                         &cinode->flags);
 689
 690                                 cfile->oplock_epoch = 0;
 691                                 cfile->oplock_level = rsp->OplockLevel;
 692
 693                                 spin_unlock(&cfile->file_info_lock);
 694
 695                                 cifs_queue_oplock_break(cfile);
 696
 697                                 spin_unlock(&tcon->open_file_lock);
 698                                 spin_unlock(&cifs_tcp_ses_lock);
 699                                 return true;
 700                         }
 701                         spin_unlock(&tcon->open_file_lock);
 702                 }
 703         }
 704         spin_unlock(&cifs_tcp_ses_lock);
 705         cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
 706         return false;
 707 }
 708
 709 void
 710 smb2_cancelled_close_fid(struct work_struct *work)
 711 {
 712         struct close_cancelled_open *cancelled = container_of(work,
 713                                         struct close_cancelled_open, work);
 714         struct cifs_tcon *tcon = cancelled->tcon;
 715         int rc;
 716
 717         if (cancelled->mid)
 718                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llx\n",
 719                               cancelled->mid);
 720         else
 721                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
 722
 723         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
 724                         cancelled->fid.volatile_fid);
 725         if (rc)
 726                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 727
 728         cifs_put_tcon(tcon);
 729         kfree(cancelled);
 730 }
 731
 732 /*
 733  * Caller should already has an extra reference to @tcon
 734  * This function is used to queue work to close a handle to prevent leaks
 735  * on the server.
 736  * We handle two cases. If an open was interrupted after we sent the
 737  * SMB2_CREATE to the server but before we processed the reply, and second
 738  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
 739  */
 740 static int
 741 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 742                             __u64 persistent_fid, __u64 volatile_fid)
 743 {
 744         struct close_cancelled_open *cancelled;
 745
 746         cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
 747         if (!cancelled)
 748                 return -ENOMEM;
 749
 750         cancelled->fid.persistent_fid = persistent_fid;
 751         cancelled->fid.volatile_fid = volatile_fid;
 752         cancelled->tcon = tcon;
 753         cancelled->cmd = cmd;
 754         cancelled->mid = mid;
 755         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 756         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
 757
 758         return 0;
 759 }
 760
 761 int
 762 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 763                             __u64 volatile_fid)
 764 {
 765         int rc;
 766
 767         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 768         spin_lock(&cifs_tcp_ses_lock);
 769         if (tcon->tc_count <= 0) {
 770                 struct TCP_Server_Info *server = NULL;
 771
 772                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 773                 spin_unlock(&cifs_tcp_ses_lock);
 774
 775                 if (tcon->ses)
 776                         server = tcon->ses->server;
 777
 778                 cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
 779                                 tcon->tid, persistent_fid, volatile_fid);
 780
 781                 return 0;
 782         }
 783         tcon->tc_count++;
 784         spin_unlock(&cifs_tcp_ses_lock);
 785
 786         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 787                                          persistent_fid, volatile_fid);
 788         if (rc)
 789                 cifs_put_tcon(tcon);
 790
 791         return rc;
 792 }
 793
 794 int
 795 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
 796 {
 797         struct smb2_sync_hdr *sync_hdr = (struct smb2_sync_hdr *)buffer;
 798         struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
 799         struct cifs_tcon *tcon;
 800         int rc;
 801
 802         if (sync_hdr->Command != SMB2_CREATE ||
 803             sync_hdr->Status != STATUS_SUCCESS)
 804                 return 0;
 805
 806         tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
 807                                   sync_hdr->TreeId);
 808         if (!tcon)
 809                 return -ENOENT;
 810
 811         rc = __smb2_handle_cancelled_cmd(tcon,
 812                                          le16_to_cpu(sync_hdr->Command),
 813                                          le64_to_cpu(sync_hdr->MessageId),
 814                                          rsp->PersistentFileId,
 815                                          rsp->VolatileFileId);
 816         if (rc)
 817                 cifs_put_tcon(tcon);
 818
 819         return rc;
 820 }
 821
 822 /**
 823  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 824  *
 825  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 826  * SMB2 header.
 827  */
 828 int
 829 smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
 830 {
 831         int i, rc;
 832         struct sdesc *d;
 833         struct smb2_sync_hdr *hdr;
 834         struct TCP_Server_Info *server = cifs_ses_server(ses);
 835
 836         hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
 837         /* neg prot are always taken */
 838         if (hdr->Command == SMB2_NEGOTIATE)
 839                 goto ok;
 840
 841         /*
 842          * If we process a command which wasn't a negprot it means the
 843          * neg prot was already done, so the server dialect was set
 844          * and we can test it. Preauth requires 3.1.1 for now.
 845          */
 846         if (server->dialect != SMB311_PROT_ID)
 847                 return 0;
 848
 849         if (hdr->Command != SMB2_SESSION_SETUP)
 850                 return 0;
 851
 852         /* skip last sess setup response */
 853         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 854             && (hdr->Status == NT_STATUS_OK
 855                 || (hdr->Status !=
 856                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
 857                 return 0;
 858
 859 ok:
 860         rc = smb311_crypto_shash_allocate(server);
 861         if (rc)
 862                 return rc;
 863
 864         d = server->secmech.sdescsha512;
 865         rc = crypto_shash_init(&d->shash);
 866         if (rc) {
 867                 cifs_dbg(VFS, "%s: could not init sha512 shash\n", __func__);
 868                 return rc;
 869         }
 870
 871         rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
 872                                  SMB2_PREAUTH_HASH_SIZE);
 873         if (rc) {
 874                 cifs_dbg(VFS, "%s: could not update sha512 shash\n", __func__);
 875                 return rc;
 876         }
 877
 878         for (i = 0; i < nvec; i++) {
 879                 rc = crypto_shash_update(&d->shash,
 880                                          iov[i].iov_base, iov[i].iov_len);
 881                 if (rc) {
 882                         cifs_dbg(VFS, "%s: could not update sha512 shash\n",
 883                                  __func__);
 884                         return rc;
 885                 }
 886         }
 887
 888         rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
 889         if (rc) {
 890                 cifs_dbg(VFS, "%s: could not finalize sha512 shash\n",
 891                          __func__);
 892                 return rc;
 893         }
 894
 895         return 0;
 896 }