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 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_sync_hdr) + sizeof(struct smb2_negotiate_rsp))
  98
  99 static __u32 get_neg_ctxt_len(struct smb2_sync_hdr *hdr, __u32 len,
 100                               __u32 non_ctxlen)
 101 {
 102         __u16 neg_count;
 103         __u32 nc_offset, size_of_pad_before_neg_ctxts;
 104         struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
 105
 106         /* Negotiate contexts are only valid for latest dialect SMB3.11 */
 107         neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
 108         if ((neg_count == 0) ||
 109            (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
 110                 return 0;
 111
 112         /* Make sure that negotiate contexts start after gss security blob */
 113         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
 114         if (nc_offset + 1 < non_ctxlen) {
 115                 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
 116                 return 0;
 117         } else if (nc_offset + 1 == non_ctxlen) {
 118                 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
 119                 size_of_pad_before_neg_ctxts = 0;
 120         } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE)
 121                 /* has padding, but no SPNEGO blob */
 122                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
 123         else
 124                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 125
 126         /* Verify that at least minimal negotiate contexts fit within frame */
 127         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
 128                 pr_warn_once("negotiate context goes beyond end\n");
 129                 return 0;
 130         }
 131
 132         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
 133                 len - nc_offset, size_of_pad_before_neg_ctxts);
 134
 135         /* length of negcontexts including pad from end of sec blob to them */
 136         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
 137 }
 138
 139 int
 140 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 141 {
 142         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
 143         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
 144         __u64 mid;
 145         __u32 clc_len;  /* calculated length */
 146         int command;
 147         int pdu_size = sizeof(struct smb2_sync_pdu);
 148         int hdr_size = sizeof(struct smb2_sync_hdr);
 149
 150         /*
 151          * Add function to do table lookup of StructureSize by command
 152          * ie Validate the wct via smb2_struct_sizes table above
 153          */
 154         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 155                 struct smb2_transform_hdr *thdr =
 156                         (struct smb2_transform_hdr *)buf;
 157                 struct cifs_ses *ses = NULL;
 158                 struct list_head *tmp;
 159
 160                 /* decrypt frame now that it is completely read in */
 161                 spin_lock(&cifs_tcp_ses_lock);
 162                 list_for_each(tmp, &srvr->smb_ses_list) {
 163                         ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 164                         if (ses->Suid == thdr->SessionId)
 165                                 break;
 166
 167                         ses = NULL;
 168                 }
 169                 spin_unlock(&cifs_tcp_ses_lock);
 170                 if (ses == NULL) {
 171                         cifs_dbg(VFS, "no decryption - session id not found\n");
 172                         return 1;
 173                 }
 174         }
 175
 176         mid = le64_to_cpu(shdr->MessageId);
 177         if (len < pdu_size) {
 178                 if ((len >= hdr_size)
 179                     && (shdr->Status != 0)) {
 180                         pdu->StructureSize2 = 0;
 181                         /*
 182                          * As with SMB/CIFS, on some error cases servers may
 183                          * not return wct properly
 184                          */
 185                         return 0;
 186                 } else {
 187                         cifs_dbg(VFS, "Length less than SMB header size\n");
 188                 }
 189                 return 1;
 190         }
 191         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 192                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 193                          mid);
 194                 return 1;
 195         }
 196
 197         if (check_smb2_hdr(shdr, mid))
 198                 return 1;
 199
 200         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 201                 cifs_dbg(VFS, "Invalid structure size %u\n",
 202                          le16_to_cpu(shdr->StructureSize));
 203                 return 1;
 204         }
 205
 206         command = le16_to_cpu(shdr->Command);
 207         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 208                 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
 209                 return 1;
 210         }
 211
 212         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 213                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 214                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
 215                         /* error packets have 9 byte structure size */
 216                         cifs_dbg(VFS, "Invalid response size %u for command %d\n",
 217                                  le16_to_cpu(pdu->StructureSize2), command);
 218                         return 1;
 219                 } else if (command == SMB2_OPLOCK_BREAK_HE
 220                            && (shdr->Status == 0)
 221                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 222                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 223                         /* special case for SMB2.1 lease break message */
 224                         cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
 225                                  le16_to_cpu(pdu->StructureSize2));
 226                         return 1;
 227                 }
 228         }
 229
 230         clc_len = smb2_calc_size(buf, srvr);
 231
 232         if (shdr->Command == SMB2_NEGOTIATE)
 233                 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
 234
 235         if (len != clc_len) {
 236                 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
 237                          clc_len, len, mid);
 238                 /* create failed on symlink */
 239                 if (command == SMB2_CREATE_HE &&
 240                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 241                         return 0;
 242                 /* Windows 7 server returns 24 bytes more */
 243                 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 244                         return 0;
 245                 /* server can return one byte more due to implied bcc[0] */
 246                 if (clc_len == len + 1)
 247                         return 0;
 248
 249                 /*
 250                  * Some windows servers (win2016) will pad also the final
 251                  * PDU in a compound to 8 bytes.
 252                  */
 253                 if (((clc_len + 7) & ~7) == len)
 254                         return 0;
 255
 256                 /*
 257                  * MacOS server pads after SMB2.1 write response with 3 bytes
 258                  * of junk. Other servers match RFC1001 len to actual
 259                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 260                  * Some windows servers also pad up to 8 bytes when compounding.
 261                  */
 262                 if (clc_len < len)
 263                         return 0;
 264
 265                 pr_warn_once(
 266                         "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
 267                         len, clc_len, command, mid);
 268
 269                 return 1;
 270         }
 271         return 0;
 272 }
 273
 274 /*
 275  * The size of the variable area depends on the offset and length fields
 276  * located in different fields for various SMB2 responses. SMB2 responses
 277  * with no variable length info, show an offset of zero for the offset field.
 278  */
 279 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 280         /* SMB2_NEGOTIATE */ true,
 281         /* SMB2_SESSION_SETUP */ true,
 282         /* SMB2_LOGOFF */ false,
 283         /* SMB2_TREE_CONNECT */ false,
 284         /* SMB2_TREE_DISCONNECT */ false,
 285         /* SMB2_CREATE */ true,
 286         /* SMB2_CLOSE */ false,
 287         /* SMB2_FLUSH */ false,
 288         /* SMB2_READ */ true,
 289         /* SMB2_WRITE */ false,
 290         /* SMB2_LOCK */ false,
 291         /* SMB2_IOCTL */ true,
 292         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 293         /* SMB2_ECHO */ false,
 294         /* SMB2_QUERY_DIRECTORY */ true,
 295         /* SMB2_CHANGE_NOTIFY */ true,
 296         /* SMB2_QUERY_INFO */ true,
 297         /* SMB2_SET_INFO */ false,
 298         /* SMB2_OPLOCK_BREAK */ false
 299 };
 300
 301 /*
 302  * Returns the pointer to the beginning of the data area. Length of the data
 303  * area and the offset to it (from the beginning of the smb are also returned.
 304  */
 305 char *
 306 smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
 307 {
 308         *off = 0;
 309         *len = 0;
 310
 311         /* error responses do not have data area */
 312         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 313             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 314                                                 SMB2_ERROR_STRUCTURE_SIZE2)
 315                 return NULL;
 316
 317         /*
 318          * Following commands have data areas so we have to get the location
 319          * of the data buffer offset and data buffer length for the particular
 320          * command.
 321          */
 322         switch (shdr->Command) {
 323         case SMB2_NEGOTIATE:
 324                 *off = le16_to_cpu(
 325                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 326                 *len = le16_to_cpu(
 327                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 328                 break;
 329         case SMB2_SESSION_SETUP:
 330                 *off = le16_to_cpu(
 331                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 332                 *len = le16_to_cpu(
 333                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 334                 break;
 335         case SMB2_CREATE:
 336                 *off = le32_to_cpu(
 337                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 338                 *len = le32_to_cpu(
 339                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 340                 break;
 341         case SMB2_QUERY_INFO:
 342                 *off = le16_to_cpu(
 343                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 344                 *len = le32_to_cpu(
 345                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 346                 break;
 347         case SMB2_READ:
 348                 /* TODO: is this a bug ? */
 349                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 350                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 351                 break;
 352         case SMB2_QUERY_DIRECTORY:
 353                 *off = le16_to_cpu(
 354                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 355                 *len = le32_to_cpu(
 356                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 357                 break;
 358         case SMB2_IOCTL:
 359                 *off = le32_to_cpu(
 360                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 361                 *len = le32_to_cpu(
 362                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 363                 break;
 364         case SMB2_CHANGE_NOTIFY:
 365                 *off = le16_to_cpu(
 366                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
 367                 *len = le32_to_cpu(
 368                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
 369                 break;
 370         default:
 371                 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
 372                 break;
 373         }
 374
 375         /*
 376          * Invalid length or offset probably means data area is invalid, but
 377          * we have little choice but to ignore the data area in this case.
 378          */
 379         if (*off > 4096) {
 380                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 381                 *len = 0;
 382                 *off = 0;
 383         } else if (*off < 0) {
 384                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 385                          *off);
 386                 *off = 0;
 387                 *len = 0;
 388         } else if (*len < 0) {
 389                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 390                          *len);
 391                 *len = 0;
 392         } else if (*len > 128 * 1024) {
 393                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 394                 *len = 0;
 395         }
 396
 397         /* return pointer to beginning of data area, ie offset from SMB start */
 398         if ((*off != 0) && (*len != 0))
 399                 return (char *)shdr + *off;
 400         else
 401                 return NULL;
 402 }
 403
 404 /*
 405  * Calculate the size of the SMB message based on the fixed header
 406  * portion, the number of word parameters and the data portion of the message.
 407  */
 408 unsigned int
 409 smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 410 {
 411         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
 412         struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
 413         int offset; /* the offset from the beginning of SMB to data area */
 414         int data_length; /* the length of the variable length data area */
 415         /* Structure Size has already been checked to make sure it is 64 */
 416         int len = le16_to_cpu(shdr->StructureSize);
 417
 418         /*
 419          * StructureSize2, ie length of fixed parameter area has already
 420          * been checked to make sure it is the correct length.
 421          */
 422         len += le16_to_cpu(pdu->StructureSize2);
 423
 424         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 425                 goto calc_size_exit;
 426
 427         smb2_get_data_area_len(&offset, &data_length, shdr);
 428         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 429
 430         if (data_length > 0) {
 431                 /*
 432                  * Check to make sure that data area begins after fixed area,
 433                  * Note that last byte of the fixed area is part of data area
 434                  * for some commands, typically those with odd StructureSize,
 435                  * so we must add one to the calculation.
 436                  */
 437                 if (offset + 1 < len) {
 438                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
 439                                  offset + 1, len);
 440                         data_length = 0;
 441                 } else {
 442                         len = offset + data_length;
 443                 }
 444         }
 445 calc_size_exit:
 446         cifs_dbg(FYI, "SMB2 len %d\n", len);
 447         return len;
 448 }
 449
 450 /* Note: caller must free return buffer */
 451 __le16 *
 452 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 453 {
 454         int len;
 455         const char *start_of_path;
 456         __le16 *to;
 457         int map_type;
 458
 459         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 460                 map_type = SFM_MAP_UNI_RSVD;
 461         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 462                 map_type = SFU_MAP_UNI_RSVD;
 463         else
 464                 map_type = NO_MAP_UNI_RSVD;
 465
 466         /* Windows doesn't allow paths beginning with \ */
 467         if (from[0] == '\\')
 468                 start_of_path = from + 1;
 469
 470         /* SMB311 POSIX extensions paths do not include leading slash */
 471         else if (cifs_sb_master_tlink(cifs_sb) &&
 472                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 473                  (from[0] == '/')) {
 474                 start_of_path = from + 1;
 475         } else
 476                 start_of_path = from;
 477
 478         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 479                                    cifs_sb->local_nls, map_type);
 480         return to;
 481 }
 482
 483 __le32
 484 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 485 {
 486         __le32 lease = 0;
 487
 488         if (CIFS_CACHE_WRITE(cinode))
 489                 lease |= SMB2_LEASE_WRITE_CACHING;
 490         if (CIFS_CACHE_HANDLE(cinode))
 491                 lease |= SMB2_LEASE_HANDLE_CACHING;
 492         if (CIFS_CACHE_READ(cinode))
 493                 lease |= SMB2_LEASE_READ_CACHING;
 494         return lease;
 495 }
 496
 497 struct smb2_lease_break_work {
 498         struct work_struct lease_break;
 499         struct tcon_link *tlink;
 500         __u8 lease_key[16];
 501         __le32 lease_state;
 502 };
 503
 504 static void
 505 cifs_ses_oplock_break(struct work_struct *work)
 506 {
 507         struct smb2_lease_break_work *lw = container_of(work,
 508                                 struct smb2_lease_break_work, lease_break);
 509         int rc = 0;
 510
 511         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 512                               lw->lease_state);
 513
 514         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 515         cifs_put_tlink(lw->tlink);
 516         kfree(lw);
 517 }
 518
 519 static void
 520 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
 521                               __le32 new_lease_state)
 522 {
 523         struct smb2_lease_break_work *lw;
 524
 525         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 526         if (!lw) {
 527                 cifs_put_tlink(tlink);
 528                 return;
 529         }
 530
 531         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 532         lw->tlink = tlink;
 533         lw->lease_state = new_lease_state;
 534         memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
 535         queue_work(cifsiod_wq, &lw->lease_break);
 536 }
 537
 538 static bool
 539 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 540 {
 541         __u8 lease_state;
 542         struct list_head *tmp;
 543         struct cifsFileInfo *cfile;
 544         struct cifsInodeInfo *cinode;
 545         int ack_req = le32_to_cpu(rsp->Flags &
 546                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 547
 548         lease_state = le32_to_cpu(rsp->NewLeaseState);
 549
 550         list_for_each(tmp, &tcon->openFileList) {
 551                 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
 552                 cinode = CIFS_I(d_inode(cfile->dentry));
 553
 554                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 555                                                         SMB2_LEASE_KEY_SIZE))
 556                         continue;
 557
 558                 cifs_dbg(FYI, "found in the open list\n");
 559                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 560                          lease_state);
 561
 562                 if (ack_req)
 563                         cfile->oplock_break_cancelled = false;
 564                 else
 565                         cfile->oplock_break_cancelled = true;
 566
 567                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 568
 569                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 570                 cfile->oplock_level = lease_state;
 571
 572                 cifs_queue_oplock_break(cfile);
 573                 return true;
 574         }
 575
 576         return false;
 577 }
 578
 579 static struct cifs_pending_open *
 580 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
 581                                   struct smb2_lease_break *rsp)
 582 {
 583         __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
 584         int ack_req = le32_to_cpu(rsp->Flags &
 585                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 586         struct cifs_pending_open *open;
 587         struct cifs_pending_open *found = NULL;
 588
 589         list_for_each_entry(open, &tcon->pending_opens, olist) {
 590                 if (memcmp(open->lease_key, rsp->LeaseKey,
 591                            SMB2_LEASE_KEY_SIZE))
 592                         continue;
 593
 594                 if (!found && ack_req) {
 595                         found = open;
 596                 }
 597
 598                 cifs_dbg(FYI, "found in the pending open list\n");
 599                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 600                          lease_state);
 601
 602                 open->oplock = lease_state;
 603         }
 604
 605         return found;
 606 }
 607
 608 static bool
 609 smb2_is_valid_lease_break(char *buffer)
 610 {
 611         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 612         struct list_head *tmp, *tmp1, *tmp2;
 613         struct TCP_Server_Info *server;
 614         struct cifs_ses *ses;
 615         struct cifs_tcon *tcon;
 616         struct cifs_pending_open *open;
 617
 618         cifs_dbg(FYI, "Checking for lease break\n");
 619
 620         /* look up tcon based on tid & uid */
 621         spin_lock(&cifs_tcp_ses_lock);
 622         list_for_each(tmp, &cifs_tcp_ses_list) {
 623                 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 624
 625                 list_for_each(tmp1, &server->smb_ses_list) {
 626                         ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 627
 628                         list_for_each(tmp2, &ses->tcon_list) {
 629                                 tcon = list_entry(tmp2, struct cifs_tcon,
 630                                                   tcon_list);
 631                                 spin_lock(&tcon->open_file_lock);
 632                                 cifs_stats_inc(
 633                                     &tcon->stats.cifs_stats.num_oplock_brks);
 634                                 if (smb2_tcon_has_lease(tcon, rsp)) {
 635                                         spin_unlock(&tcon->open_file_lock);
 636                                         spin_unlock(&cifs_tcp_ses_lock);
 637                                         return true;
 638                                 }
 639                                 open = smb2_tcon_find_pending_open_lease(tcon,
 640                                                                          rsp);
 641                                 if (open) {
 642                                         __u8 lease_key[SMB2_LEASE_KEY_SIZE];
 643                                         struct tcon_link *tlink;
 644
 645                                         tlink = cifs_get_tlink(open->tlink);
 646                                         memcpy(lease_key, open->lease_key,
 647                                                SMB2_LEASE_KEY_SIZE);
 648                                         spin_unlock(&tcon->open_file_lock);
 649                                         spin_unlock(&cifs_tcp_ses_lock);
 650                                         smb2_queue_pending_open_break(tlink,
 651                                                                       lease_key,
 652                                                                       rsp->NewLeaseState);
 653                                         return true;
 654                                 }
 655                                 spin_unlock(&tcon->open_file_lock);
 656
 657                                 if (tcon->crfid.is_valid &&
 658                                     !memcmp(rsp->LeaseKey,
 659                                             tcon->crfid.fid->lease_key,
 660                                             SMB2_LEASE_KEY_SIZE)) {
 661                                         INIT_WORK(&tcon->crfid.lease_break,
 662                                                   smb2_cached_lease_break);
 663                                         queue_work(cifsiod_wq,
 664                                                    &tcon->crfid.lease_break);
 665                                         spin_unlock(&cifs_tcp_ses_lock);
 666                                         return true;
 667                                 }
 668                         }
 669                 }
 670         }
 671         spin_unlock(&cifs_tcp_ses_lock);
 672         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 673         return false;
 674 }
 675
 676 bool
 677 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 678 {
 679         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 680         struct list_head *tmp, *tmp1, *tmp2;
 681         struct cifs_ses *ses;
 682         struct cifs_tcon *tcon;
 683         struct cifsInodeInfo *cinode;
 684         struct cifsFileInfo *cfile;
 685
 686         cifs_dbg(FYI, "Checking for oplock break\n");
 687
 688         if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
 689                 return false;
 690
 691         if (rsp->StructureSize !=
 692                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 693                 if (le16_to_cpu(rsp->StructureSize) == 44)
 694                         return smb2_is_valid_lease_break(buffer);
 695                 else
 696                         return false;
 697         }
 698
 699         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 700
 701         /* look up tcon based on tid & uid */
 702         spin_lock(&cifs_tcp_ses_lock);
 703         list_for_each(tmp, &server->smb_ses_list) {
 704                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 705
 706                 list_for_each(tmp1, &ses->tcon_list) {
 707                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
 708
 709                         spin_lock(&tcon->open_file_lock);
 710                         list_for_each(tmp2, &tcon->openFileList) {
 711                                 cfile = list_entry(tmp2, struct cifsFileInfo,
 712                                                      tlist);
 713                                 if (rsp->PersistentFid !=
 714                                     cfile->fid.persistent_fid ||
 715                                     rsp->VolatileFid !=
 716                                     cfile->fid.volatile_fid)
 717                                         continue;
 718
 719                                 cifs_dbg(FYI, "file id match, oplock break\n");
 720                                 cifs_stats_inc(
 721                                     &tcon->stats.cifs_stats.num_oplock_brks);
 722                                 cinode = CIFS_I(d_inode(cfile->dentry));
 723                                 spin_lock(&cfile->file_info_lock);
 724                                 if (!CIFS_CACHE_WRITE(cinode) &&
 725                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 726                                         cfile->oplock_break_cancelled = true;
 727                                 else
 728                                         cfile->oplock_break_cancelled = false;
 729
 730                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 731                                         &cinode->flags);
 732
 733                                 cfile->oplock_epoch = 0;
 734                                 cfile->oplock_level = rsp->OplockLevel;
 735
 736                                 spin_unlock(&cfile->file_info_lock);
 737
 738                                 cifs_queue_oplock_break(cfile);
 739
 740                                 spin_unlock(&tcon->open_file_lock);
 741                                 spin_unlock(&cifs_tcp_ses_lock);
 742                                 return true;
 743                         }
 744                         spin_unlock(&tcon->open_file_lock);
 745                 }
 746         }
 747         spin_unlock(&cifs_tcp_ses_lock);
 748         cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
 749         return true;
 750 }
 751
 752 void
 753 smb2_cancelled_close_fid(struct work_struct *work)
 754 {
 755         struct close_cancelled_open *cancelled = container_of(work,
 756                                         struct close_cancelled_open, work);
 757         struct cifs_tcon *tcon = cancelled->tcon;
 758         int rc;
 759
 760         if (cancelled->mid)
 761                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llx\n",
 762                               cancelled->mid);
 763         else
 764                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
 765
 766         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
 767                         cancelled->fid.volatile_fid);
 768         if (rc)
 769                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 770
 771         cifs_put_tcon(tcon);
 772         kfree(cancelled);
 773 }
 774
 775 /*
 776  * Caller should already has an extra reference to @tcon
 777  * This function is used to queue work to close a handle to prevent leaks
 778  * on the server.
 779  * We handle two cases. If an open was interrupted after we sent the
 780  * SMB2_CREATE to the server but before we processed the reply, and second
 781  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
 782  */
 783 static int
 784 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 785                             __u64 persistent_fid, __u64 volatile_fid)
 786 {
 787         struct close_cancelled_open *cancelled;
 788
 789         cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
 790         if (!cancelled)
 791                 return -ENOMEM;
 792
 793         cancelled->fid.persistent_fid = persistent_fid;
 794         cancelled->fid.volatile_fid = volatile_fid;
 795         cancelled->tcon = tcon;
 796         cancelled->cmd = cmd;
 797         cancelled->mid = mid;
 798         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 799         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
 800
 801         return 0;
 802 }
 803
 804 int
 805 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 806                             __u64 volatile_fid)
 807 {
 808         int rc;
 809
 810         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 811         spin_lock(&cifs_tcp_ses_lock);
 812         if (tcon->tc_count <= 0) {
 813                 struct TCP_Server_Info *server = NULL;
 814
 815                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 816                 spin_unlock(&cifs_tcp_ses_lock);
 817
 818                 if (tcon->ses)
 819                         server = tcon->ses->server;
 820
 821                 cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
 822                                 tcon->tid, persistent_fid, volatile_fid);
 823
 824                 return 0;
 825         }
 826         tcon->tc_count++;
 827         spin_unlock(&cifs_tcp_ses_lock);
 828
 829         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 830                                          persistent_fid, volatile_fid);
 831         if (rc)
 832                 cifs_put_tcon(tcon);
 833
 834         return rc;
 835 }
 836
 837 int
 838 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 839 {
 840         struct smb2_sync_hdr *sync_hdr = mid->resp_buf;
 841         struct smb2_create_rsp *rsp = mid->resp_buf;
 842         struct cifs_tcon *tcon;
 843         int rc;
 844
 845         if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || sync_hdr->Command != SMB2_CREATE ||
 846             sync_hdr->Status != STATUS_SUCCESS)
 847                 return 0;
 848
 849         tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
 850                                   sync_hdr->TreeId);
 851         if (!tcon)
 852                 return -ENOENT;
 853
 854         rc = __smb2_handle_cancelled_cmd(tcon,
 855                                          le16_to_cpu(sync_hdr->Command),
 856                                          le64_to_cpu(sync_hdr->MessageId),
 857                                          rsp->PersistentFileId,
 858                                          rsp->VolatileFileId);
 859         if (rc)
 860                 cifs_put_tcon(tcon);
 861
 862         return rc;
 863 }
 864
 865 /**
 866  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 867  *
 868  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 869  * SMB2 header.
 870  */
 871 int
 872 smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
 873 {
 874         int i, rc;
 875         struct sdesc *d;
 876         struct smb2_sync_hdr *hdr;
 877         struct TCP_Server_Info *server = cifs_ses_server(ses);
 878
 879         hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
 880         /* neg prot are always taken */
 881         if (hdr->Command == SMB2_NEGOTIATE)
 882                 goto ok;
 883
 884         /*
 885          * If we process a command which wasn't a negprot it means the
 886          * neg prot was already done, so the server dialect was set
 887          * and we can test it. Preauth requires 3.1.1 for now.
 888          */
 889         if (server->dialect != SMB311_PROT_ID)
 890                 return 0;
 891
 892         if (hdr->Command != SMB2_SESSION_SETUP)
 893                 return 0;
 894
 895         /* skip last sess setup response */
 896         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 897             && (hdr->Status == NT_STATUS_OK
 898                 || (hdr->Status !=
 899                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
 900                 return 0;
 901
 902 ok:
 903         rc = smb311_crypto_shash_allocate(server);
 904         if (rc)
 905                 return rc;
 906
 907         d = server->secmech.sdescsha512;
 908         rc = crypto_shash_init(&d->shash);
 909         if (rc) {
 910                 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
 911                 return rc;
 912         }
 913
 914         rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
 915                                  SMB2_PREAUTH_HASH_SIZE);
 916         if (rc) {
 917                 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
 918                 return rc;
 919         }
 920
 921         for (i = 0; i < nvec; i++) {
 922                 rc = crypto_shash_update(&d->shash,
 923                                          iov[i].iov_base, iov[i].iov_len);
 924                 if (rc) {
 925                         cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
 926                                  __func__);
 927                         return rc;
 928                 }
 929         }
 930
 931         rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
 932         if (rc) {
 933                 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
 934                          __func__);
 935                 return rc;
 936         }
 937
 938         return 0;
 939 }