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
  33 static int
  34 check_smb2_hdr(struct smb2_sync_hdr *shdr, __u64 mid)
  35 {
  36         __u64 wire_mid = le64_to_cpu(shdr->MessageId);
  37
  38         /*
  39          * Make sure that this really is an SMB, that it is a response,
  40          * and that the message ids match.
  41          */
  42         if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
  43             (mid == wire_mid)) {
  44                 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
  45                         return 0;
  46                 else {
  47                         /* only one valid case where server sends us request */
  48                         if (shdr->Command == SMB2_OPLOCK_BREAK)
  49                                 return 0;
  50                         else
  51                                 cifs_dbg(VFS, "Received Request not response\n");
  52                 }
  53         } else { /* bad signature or mid */
  54                 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
  55                         cifs_dbg(VFS, "Bad protocol string signature header %x\n",
  56                                  le32_to_cpu(shdr->ProtocolId));
  57                 if (mid != wire_mid)
  58                         cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
  59                                  mid, wire_mid);
  60         }
  61         cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
  62         return 1;
  63 }
  64
  65 /*
  66  *  The following table defines the expected "StructureSize" of SMB2 responses
  67  *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
  68  *
  69  *  Note that commands are defined in smb2pdu.h in le16 but the array below is
  70  *  indexed by command in host byte order
  71  */
  72 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
  73         /* SMB2_NEGOTIATE */ cpu_to_le16(65),
  74         /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
  75         /* SMB2_LOGOFF */ cpu_to_le16(4),
  76         /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
  77         /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
  78         /* SMB2_CREATE */ cpu_to_le16(89),
  79         /* SMB2_CLOSE */ cpu_to_le16(60),
  80         /* SMB2_FLUSH */ cpu_to_le16(4),
  81         /* SMB2_READ */ cpu_to_le16(17),
  82         /* SMB2_WRITE */ cpu_to_le16(17),
  83         /* SMB2_LOCK */ cpu_to_le16(4),
  84         /* SMB2_IOCTL */ cpu_to_le16(49),
  85         /* BB CHECK this ... not listed in documentation */
  86         /* SMB2_CANCEL */ cpu_to_le16(0),
  87         /* SMB2_ECHO */ cpu_to_le16(4),
  88         /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
  89         /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
  90         /* SMB2_QUERY_INFO */ cpu_to_le16(9),
  91         /* SMB2_SET_INFO */ cpu_to_le16(2),
  92         /* BB FIXME can also be 44 for lease break */
  93         /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
  94 };
  95
  96 static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
  97                               __u32 non_ctxlen)
  98 {
  99         __u16 neg_count;
 100         __u32 nc_offset, size_of_pad_before_neg_ctxts;
 101         struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
 102
 103         /* Negotiate contexts are only valid for latest dialect SMB3.11 */
 104         neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
 105         if ((neg_count == 0) ||
 106            (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
 107                 return 0;
 108
 109         /* Make sure that negotiate contexts start after gss security blob */
 110         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
 111         if (nc_offset < non_ctxlen) {
 112                 printk_once(KERN_WARNING "invalid negotiate context offset\n");
 113                 return 0;
 114         }
 115         size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 116
 117         /* Verify that at least minimal negotiate contexts fit within frame */
 118         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
 119                 printk_once(KERN_WARNING "negotiate context goes beyond end\n");
 120                 return 0;
 121         }
 122
 123         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
 124                 len - nc_offset, size_of_pad_before_neg_ctxts);
 125
 126         /* length of negcontexts including pad from end of sec blob to them */
 127         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
 128 }
 129
 130 int
 131 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 132 {
 133         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
 134         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
 135         __u64 mid;
 136         __u32 clc_len;  /* calculated length */
 137         int command;
 138         int pdu_size = sizeof(struct smb2_sync_pdu);
 139         int hdr_size = sizeof(struct smb2_sync_hdr);
 140
 141         /*
 142          * Add function to do table lookup of StructureSize by command
 143          * ie Validate the wct via smb2_struct_sizes table above
 144          */
 145         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 146                 struct smb2_transform_hdr *thdr =
 147                         (struct smb2_transform_hdr *)buf;
 148                 struct cifs_ses *ses = NULL;
 149                 struct list_head *tmp;
 150
 151                 /* decrypt frame now that it is completely read in */
 152                 spin_lock(&cifs_tcp_ses_lock);
 153                 list_for_each(tmp, &srvr->smb_ses_list) {
 154                         ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 155                         if (ses->Suid == thdr->SessionId)
 156                                 break;
 157
 158                         ses = NULL;
 159                 }
 160                 spin_unlock(&cifs_tcp_ses_lock);
 161                 if (ses == NULL) {
 162                         cifs_dbg(VFS, "no decryption - session id not found\n");
 163                         return 1;
 164                 }
 165         }
 166
 167         mid = le64_to_cpu(shdr->MessageId);
 168         if (len < pdu_size) {
 169                 if ((len >= hdr_size)
 170                     && (shdr->Status != 0)) {
 171                         pdu->StructureSize2 = 0;
 172                         /*
 173                          * As with SMB/CIFS, on some error cases servers may
 174                          * not return wct properly
 175                          */
 176                         return 0;
 177                 } else {
 178                         cifs_dbg(VFS, "Length less than SMB header size\n");
 179                 }
 180                 return 1;
 181         }
 182         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 183                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 184                          mid);
 185                 return 1;
 186         }
 187
 188         if (check_smb2_hdr(shdr, mid))
 189                 return 1;
 190
 191         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 192                 cifs_dbg(VFS, "Illegal structure size %u\n",
 193                          le16_to_cpu(shdr->StructureSize));
 194                 return 1;
 195         }
 196
 197         command = le16_to_cpu(shdr->Command);
 198         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 199                 cifs_dbg(VFS, "Illegal SMB2 command %d\n", command);
 200                 return 1;
 201         }
 202
 203         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 204                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 205                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
 206                         /* error packets have 9 byte structure size */
 207                         cifs_dbg(VFS, "Illegal response size %u for command %d\n",
 208                                  le16_to_cpu(pdu->StructureSize2), command);
 209                         return 1;
 210                 } else if (command == SMB2_OPLOCK_BREAK_HE
 211                            && (shdr->Status == 0)
 212                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 213                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 214                         /* special case for SMB2.1 lease break message */
 215                         cifs_dbg(VFS, "Illegal response size %d for oplock break\n",
 216                                  le16_to_cpu(pdu->StructureSize2));
 217                         return 1;
 218                 }
 219         }
 220
 221         clc_len = smb2_calc_size(buf, srvr);
 222
 223         if (shdr->Command == SMB2_NEGOTIATE)
 224                 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
 225
 226         if (len != clc_len) {
 227                 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
 228                          clc_len, len, mid);
 229                 /* create failed on symlink */
 230                 if (command == SMB2_CREATE_HE &&
 231                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 232                         return 0;
 233                 /* Windows 7 server returns 24 bytes more */
 234                 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 235                         return 0;
 236                 /* server can return one byte more due to implied bcc[0] */
 237                 if (clc_len == len + 1)
 238                         return 0;
 239
 240                 /*
 241                  * Some windows servers (win2016) will pad also the final
 242                  * PDU in a compound to 8 bytes.
 243                  */
 244                 if (((clc_len + 7) & ~7) == len)
 245                         return 0;
 246
 247                 /*
 248                  * MacOS server pads after SMB2.1 write response with 3 bytes
 249                  * of junk. Other servers match RFC1001 len to actual
 250                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 251                  * Some windows servers also pad up to 8 bytes when compounding.
 252                  * If pad is longer than eight bytes, log the server behavior
 253                  * (once), since may indicate a problem but allow it and continue
 254                  * since the frame is parseable.
 255                  */
 256                 if (clc_len < len) {
 257                         pr_warn_once(
 258                              "srv rsp padded more than expected. Length %d not %d for cmd:%d mid:%llu\n",
 259                              len, clc_len, command, mid);
 260                         return 0;
 261                 }
 262                 pr_warn_once(
 263                         "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
 264                         len, clc_len, command, mid);
 265
 266                 return 1;
 267         }
 268         return 0;
 269 }
 270
 271 /*
 272  * The size of the variable area depends on the offset and length fields
 273  * located in different fields for various SMB2 responses. SMB2 responses
 274  * with no variable length info, show an offset of zero for the offset field.
 275  */
 276 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 277         /* SMB2_NEGOTIATE */ true,
 278         /* SMB2_SESSION_SETUP */ true,
 279         /* SMB2_LOGOFF */ false,
 280         /* SMB2_TREE_CONNECT */ false,
 281         /* SMB2_TREE_DISCONNECT */ false,
 282         /* SMB2_CREATE */ true,
 283         /* SMB2_CLOSE */ false,
 284         /* SMB2_FLUSH */ false,
 285         /* SMB2_READ */ true,
 286         /* SMB2_WRITE */ false,
 287         /* SMB2_LOCK */ false,
 288         /* SMB2_IOCTL */ true,
 289         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 290         /* SMB2_ECHO */ false,
 291         /* SMB2_QUERY_DIRECTORY */ true,
 292         /* SMB2_CHANGE_NOTIFY */ true,
 293         /* SMB2_QUERY_INFO */ true,
 294         /* SMB2_SET_INFO */ false,
 295         /* SMB2_OPLOCK_BREAK */ false
 296 };
 297
 298 /*
 299  * Returns the pointer to the beginning of the data area. Length of the data
 300  * area and the offset to it (from the beginning of the smb are also returned.
 301  */
 302 char *
 303 smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
 304 {
 305         *off = 0;
 306         *len = 0;
 307
 308         /* error responses do not have data area */
 309         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 310             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 311                                                 SMB2_ERROR_STRUCTURE_SIZE2)
 312                 return NULL;
 313
 314         /*
 315          * Following commands have data areas so we have to get the location
 316          * of the data buffer offset and data buffer length for the particular
 317          * command.
 318          */
 319         switch (shdr->Command) {
 320         case SMB2_NEGOTIATE:
 321                 *off = le16_to_cpu(
 322                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 323                 *len = le16_to_cpu(
 324                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 325                 break;
 326         case SMB2_SESSION_SETUP:
 327                 *off = le16_to_cpu(
 328                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 329                 *len = le16_to_cpu(
 330                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 331                 break;
 332         case SMB2_CREATE:
 333                 *off = le32_to_cpu(
 334                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 335                 *len = le32_to_cpu(
 336                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 337                 break;
 338         case SMB2_QUERY_INFO:
 339                 *off = le16_to_cpu(
 340                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 341                 *len = le32_to_cpu(
 342                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 343                 break;
 344         case SMB2_READ:
 345                 /* TODO: is this a bug ? */
 346                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 347                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 348                 break;
 349         case SMB2_QUERY_DIRECTORY:
 350                 *off = le16_to_cpu(
 351                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 352                 *len = le32_to_cpu(
 353                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 354                 break;
 355         case SMB2_IOCTL:
 356                 *off = le32_to_cpu(
 357                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 358                 *len = le32_to_cpu(
 359                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 360                 break;
 361         case SMB2_CHANGE_NOTIFY:
 362         default:
 363                 /* BB FIXME for unimplemented cases above */
 364                 cifs_dbg(VFS, "no length check for command\n");
 365                 break;
 366         }
 367
 368         /*
 369          * Invalid length or offset probably means data area is invalid, but
 370          * we have little choice but to ignore the data area in this case.
 371          */
 372         if (*off > 4096) {
 373                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 374                 *len = 0;
 375                 *off = 0;
 376         } else if (*off < 0) {
 377                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 378                          *off);
 379                 *off = 0;
 380                 *len = 0;
 381         } else if (*len < 0) {
 382                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 383                          *len);
 384                 *len = 0;
 385         } else if (*len > 128 * 1024) {
 386                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 387                 *len = 0;
 388         }
 389
 390         /* return pointer to beginning of data area, ie offset from SMB start */
 391         if ((*off != 0) && (*len != 0))
 392                 return (char *)shdr + *off;
 393         else
 394                 return NULL;
 395 }
 396
 397 /*
 398  * Calculate the size of the SMB message based on the fixed header
 399  * portion, the number of word parameters and the data portion of the message.
 400  */
 401 unsigned int
 402 smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 403 {
 404         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
 405         struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
 406         int offset; /* the offset from the beginning of SMB to data area */
 407         int data_length; /* the length of the variable length data area */
 408         /* Structure Size has already been checked to make sure it is 64 */
 409         int len = le16_to_cpu(shdr->StructureSize);
 410
 411         /*
 412          * StructureSize2, ie length of fixed parameter area has already
 413          * been checked to make sure it is the correct length.
 414          */
 415         len += le16_to_cpu(pdu->StructureSize2);
 416
 417         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 418                 goto calc_size_exit;
 419
 420         smb2_get_data_area_len(&offset, &data_length, shdr);
 421         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 422
 423         if (data_length > 0) {
 424                 /*
 425                  * Check to make sure that data area begins after fixed area,
 426                  * Note that last byte of the fixed area is part of data area
 427                  * for some commands, typically those with odd StructureSize,
 428                  * so we must add one to the calculation.
 429                  */
 430                 if (offset + 1 < len) {
 431                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
 432                                  offset + 1, len);
 433                         data_length = 0;
 434                 } else {
 435                         len = offset + data_length;
 436                 }
 437         }
 438 calc_size_exit:
 439         cifs_dbg(FYI, "SMB2 len %d\n", len);
 440         return len;
 441 }
 442
 443 /* Note: caller must free return buffer */
 444 __le16 *
 445 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 446 {
 447         int len;
 448         const char *start_of_path;
 449         __le16 *to;
 450         int map_type;
 451
 452         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 453                 map_type = SFM_MAP_UNI_RSVD;
 454         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 455                 map_type = SFU_MAP_UNI_RSVD;
 456         else
 457                 map_type = NO_MAP_UNI_RSVD;
 458
 459         /* Windows doesn't allow paths beginning with \ */
 460         if (from[0] == '\\')
 461                 start_of_path = from + 1;
 462
 463         /* SMB311 POSIX extensions paths do not include leading slash */
 464         else if (cifs_sb_master_tlink(cifs_sb) &&
 465                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 466                  (from[0] == '/')) {
 467                 start_of_path = from + 1;
 468         } else
 469                 start_of_path = from;
 470
 471         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 472                                    cifs_sb->local_nls, map_type);
 473         return to;
 474 }
 475
 476 __le32
 477 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 478 {
 479         __le32 lease = 0;
 480
 481         if (CIFS_CACHE_WRITE(cinode))
 482                 lease |= SMB2_LEASE_WRITE_CACHING;
 483         if (CIFS_CACHE_HANDLE(cinode))
 484                 lease |= SMB2_LEASE_HANDLE_CACHING;
 485         if (CIFS_CACHE_READ(cinode))
 486                 lease |= SMB2_LEASE_READ_CACHING;
 487         return lease;
 488 }
 489
 490 struct smb2_lease_break_work {
 491         struct work_struct lease_break;
 492         struct tcon_link *tlink;
 493         __u8 lease_key[16];
 494         __le32 lease_state;
 495 };
 496
 497 static void
 498 cifs_ses_oplock_break(struct work_struct *work)
 499 {
 500         struct smb2_lease_break_work *lw = container_of(work,
 501                                 struct smb2_lease_break_work, lease_break);
 502         int rc = 0;
 503
 504         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 505                               lw->lease_state);
 506
 507         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 508         cifs_put_tlink(lw->tlink);
 509         kfree(lw);
 510 }
 511
 512 static bool
 513 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
 514                     struct smb2_lease_break_work *lw)
 515 {
 516         bool found;
 517         __u8 lease_state;
 518         struct list_head *tmp;
 519         struct cifsFileInfo *cfile;
 520         struct cifs_pending_open *open;
 521         struct cifsInodeInfo *cinode;
 522         int ack_req = le32_to_cpu(rsp->Flags &
 523                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 524
 525         lease_state = le32_to_cpu(rsp->NewLeaseState);
 526
 527         list_for_each(tmp, &tcon->openFileList) {
 528                 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
 529                 cinode = CIFS_I(d_inode(cfile->dentry));
 530
 531                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 532                                                         SMB2_LEASE_KEY_SIZE))
 533                         continue;
 534
 535                 cifs_dbg(FYI, "found in the open list\n");
 536                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 537                          le32_to_cpu(rsp->NewLeaseState));
 538
 539                 if (ack_req)
 540                         cfile->oplock_break_cancelled = false;
 541                 else
 542                         cfile->oplock_break_cancelled = true;
 543
 544                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 545
 546                 /*
 547                  * Set or clear flags depending on the lease state being READ.
 548                  * HANDLE caching flag should be added when the client starts
 549                  * to defer closing remote file handles with HANDLE leases.
 550                  */
 551                 if (lease_state & SMB2_LEASE_READ_CACHING_HE)
 552                         set_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
 553                                 &cinode->flags);
 554                 else
 555                         clear_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
 556                                   &cinode->flags);
 557
 558                 cifs_queue_oplock_break(cfile);
 559                 kfree(lw);
 560                 return true;
 561         }
 562
 563         found = false;
 564         list_for_each_entry(open, &tcon->pending_opens, olist) {
 565                 if (memcmp(open->lease_key, rsp->LeaseKey,
 566                            SMB2_LEASE_KEY_SIZE))
 567                         continue;
 568
 569                 if (!found && ack_req) {
 570                         found = true;
 571                         memcpy(lw->lease_key, open->lease_key,
 572                                SMB2_LEASE_KEY_SIZE);
 573                         lw->tlink = cifs_get_tlink(open->tlink);
 574                         queue_work(cifsiod_wq, &lw->lease_break);
 575                 }
 576
 577                 cifs_dbg(FYI, "found in the pending open list\n");
 578                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 579                          le32_to_cpu(rsp->NewLeaseState));
 580
 581                 open->oplock = lease_state;
 582         }
 583
 584         return found;
 585 }
 586
 587 static bool
 588 smb2_is_valid_lease_break(char *buffer)
 589 {
 590         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 591         struct list_head *tmp, *tmp1, *tmp2;
 592         struct TCP_Server_Info *server;
 593         struct cifs_ses *ses;
 594         struct cifs_tcon *tcon;
 595         struct smb2_lease_break_work *lw;
 596
 597         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 598         if (!lw)
 599                 return false;
 600
 601         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 602         lw->lease_state = rsp->NewLeaseState;
 603
 604         cifs_dbg(FYI, "Checking for lease break\n");
 605
 606         /* look up tcon based on tid & uid */
 607         spin_lock(&cifs_tcp_ses_lock);
 608         list_for_each(tmp, &cifs_tcp_ses_list) {
 609                 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 610
 611                 list_for_each(tmp1, &server->smb_ses_list) {
 612                         ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 613
 614                         list_for_each(tmp2, &ses->tcon_list) {
 615                                 tcon = list_entry(tmp2, struct cifs_tcon,
 616                                                   tcon_list);
 617                                 spin_lock(&tcon->open_file_lock);
 618                                 cifs_stats_inc(
 619                                     &tcon->stats.cifs_stats.num_oplock_brks);
 620                                 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
 621                                         spin_unlock(&tcon->open_file_lock);
 622                                         spin_unlock(&cifs_tcp_ses_lock);
 623                                         return true;
 624                                 }
 625                                 spin_unlock(&tcon->open_file_lock);
 626
 627                                 if (tcon->crfid.is_valid &&
 628                                     !memcmp(rsp->LeaseKey,
 629                                             tcon->crfid.fid->lease_key,
 630                                             SMB2_LEASE_KEY_SIZE)) {
 631                                         INIT_WORK(&tcon->crfid.lease_break,
 632                                                   smb2_cached_lease_break);
 633                                         queue_work(cifsiod_wq,
 634                                                    &tcon->crfid.lease_break);
 635                                         spin_unlock(&cifs_tcp_ses_lock);
 636                                         return true;
 637                                 }
 638                         }
 639                 }
 640         }
 641         spin_unlock(&cifs_tcp_ses_lock);
 642         kfree(lw);
 643         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 644         return false;
 645 }
 646
 647 bool
 648 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 649 {
 650         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 651         struct list_head *tmp, *tmp1, *tmp2;
 652         struct cifs_ses *ses;
 653         struct cifs_tcon *tcon;
 654         struct cifsInodeInfo *cinode;
 655         struct cifsFileInfo *cfile;
 656
 657         cifs_dbg(FYI, "Checking for oplock break\n");
 658
 659         if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
 660                 return false;
 661
 662         if (rsp->StructureSize !=
 663                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 664                 if (le16_to_cpu(rsp->StructureSize) == 44)
 665                         return smb2_is_valid_lease_break(buffer);
 666                 else
 667                         return false;
 668         }
 669
 670         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 671
 672         /* look up tcon based on tid & uid */
 673         spin_lock(&cifs_tcp_ses_lock);
 674         list_for_each(tmp, &server->smb_ses_list) {
 675                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 676                 list_for_each(tmp1, &ses->tcon_list) {
 677                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
 678
 679                         cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
 680                         spin_lock(&tcon->open_file_lock);
 681                         list_for_each(tmp2, &tcon->openFileList) {
 682                                 cfile = list_entry(tmp2, struct cifsFileInfo,
 683                                                      tlist);
 684                                 if (rsp->PersistentFid !=
 685                                     cfile->fid.persistent_fid ||
 686                                     rsp->VolatileFid !=
 687                                     cfile->fid.volatile_fid)
 688                                         continue;
 689
 690                                 cifs_dbg(FYI, "file id match, oplock break\n");
 691                                 cinode = CIFS_I(d_inode(cfile->dentry));
 692                                 spin_lock(&cfile->file_info_lock);
 693                                 if (!CIFS_CACHE_WRITE(cinode) &&
 694                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 695                                         cfile->oplock_break_cancelled = true;
 696                                 else
 697                                         cfile->oplock_break_cancelled = false;
 698
 699                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 700                                         &cinode->flags);
 701
 702                                 /*
 703                                  * Set flag if the server downgrades the oplock
 704                                  * to L2 else clear.
 705                                  */
 706                                 if (rsp->OplockLevel)
 707                                         set_bit(
 708                                            CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
 709                                            &cinode->flags);
 710                                 else
 711                                         clear_bit(
 712                                            CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
 713                                            &cinode->flags);
 714                                 spin_unlock(&cfile->file_info_lock);
 715
 716                                 cifs_queue_oplock_break(cfile);
 717
 718                                 spin_unlock(&tcon->open_file_lock);
 719                                 spin_unlock(&cifs_tcp_ses_lock);
 720                                 return true;
 721                         }
 722                         spin_unlock(&tcon->open_file_lock);
 723                         spin_unlock(&cifs_tcp_ses_lock);
 724                         cifs_dbg(FYI, "No matching file for oplock break\n");
 725                         return true;
 726                 }
 727         }
 728         spin_unlock(&cifs_tcp_ses_lock);
 729         cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
 730         return false;
 731 }
 732
 733 void
 734 smb2_cancelled_close_fid(struct work_struct *work)
 735 {
 736         struct close_cancelled_open *cancelled = container_of(work,
 737                                         struct close_cancelled_open, work);
 738
 739         cifs_dbg(VFS, "Close unmatched open\n");
 740
 741         SMB2_close(0, cancelled->tcon, cancelled->fid.persistent_fid,
 742                    cancelled->fid.volatile_fid);
 743         cifs_put_tcon(cancelled->tcon);
 744         kfree(cancelled);
 745 }
 746
 747 int
 748 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
 749 {
 750         struct smb2_sync_hdr *sync_hdr = (struct smb2_sync_hdr *)buffer;
 751         struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
 752         struct cifs_tcon *tcon;
 753         struct close_cancelled_open *cancelled;
 754
 755         if (sync_hdr->Command != SMB2_CREATE ||
 756             sync_hdr->Status != STATUS_SUCCESS)
 757                 return 0;
 758
 759         cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
 760         if (!cancelled)
 761                 return -ENOMEM;
 762
 763         tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
 764                                   sync_hdr->TreeId);
 765         if (!tcon) {
 766                 kfree(cancelled);
 767                 return -ENOENT;
 768         }
 769
 770         cancelled->fid.persistent_fid = rsp->PersistentFileId;
 771         cancelled->fid.volatile_fid = rsp->VolatileFileId;
 772         cancelled->tcon = tcon;
 773         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 774         queue_work(cifsiod_wq, &cancelled->work);
 775
 776         return 0;
 777 }
 778
 779 /**
 780  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 781  *
 782  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 783  * SMB2 header.
 784  */
 785 int
 786 smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
 787 {
 788         int i, rc;
 789         struct sdesc *d;
 790         struct smb2_sync_hdr *hdr;
 791
 792         if (ses->server->tcpStatus == CifsGood) {
 793                 /* skip non smb311 connections */
 794                 if (ses->server->dialect != SMB311_PROT_ID)
 795                         return 0;
 796
 797                 /* skip last sess setup response */
 798                 hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
 799                 if (hdr->Flags & SMB2_FLAGS_SIGNED)
 800                         return 0;
 801         }
 802
 803         rc = smb311_crypto_shash_allocate(ses->server);
 804         if (rc)
 805                 return rc;
 806
 807         d = ses->server->secmech.sdescsha512;
 808         rc = crypto_shash_init(&d->shash);
 809         if (rc) {
 810                 cifs_dbg(VFS, "%s: could not init sha512 shash\n", __func__);
 811                 return rc;
 812         }
 813
 814         rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
 815                                  SMB2_PREAUTH_HASH_SIZE);
 816         if (rc) {
 817                 cifs_dbg(VFS, "%s: could not update sha512 shash\n", __func__);
 818                 return rc;
 819         }
 820
 821         for (i = 0; i < nvec; i++) {
 822                 rc = crypto_shash_update(&d->shash,
 823                                          iov[i].iov_base, iov[i].iov_len);
 824                 if (rc) {
 825                         cifs_dbg(VFS, "%s: could not update sha512 shash\n",
 826                                  __func__);
 827                         return rc;
 828                 }
 829         }
 830
 831         rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
 832         if (rc) {
 833                 cifs_dbg(VFS, "%s: could not finalize sha512 shash\n",
 834                          __func__);
 835                 return rc;
 836         }
 837
 838         return 0;
 839 }