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         /*
 113          * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
 114          * which security mechanisms the server supports) make sure that
 115          * the negotiate contexts start after it
 116          */
 117         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
 118         /*
 119          * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
 120          * and the latter is 1 byte bigger than the fix-sized area of the
 121          * NEGOTIATE response
 122          */
 123         if (nc_offset + 1 < non_ctxlen) {
 124                 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
 125                 return 0;
 126         } else if (nc_offset + 1 == non_ctxlen) {
 127                 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
 128                 size_of_pad_before_neg_ctxts = 0;
 129         } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE)
 130                 /* has padding, but no SPNEGO blob */
 131                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
 132         else
 133                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 134
 135         /* Verify that at least minimal negotiate contexts fit within frame */
 136         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
 137                 pr_warn_once("negotiate context goes beyond end\n");
 138                 return 0;
 139         }
 140
 141         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
 142                 len - nc_offset, size_of_pad_before_neg_ctxts);
 143
 144         /* length of negcontexts including pad from end of sec blob to them */
 145         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
 146 }
 147
 148 int
 149 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 150 {
 151         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buf;
 152         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)shdr;
 153         __u64 mid;
 154         __u32 clc_len;  /* calculated length */
 155         int command;
 156         int pdu_size = sizeof(struct smb2_sync_pdu);
 157         int hdr_size = sizeof(struct smb2_sync_hdr);
 158
 159         /*
 160          * Add function to do table lookup of StructureSize by command
 161          * ie Validate the wct via smb2_struct_sizes table above
 162          */
 163         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 164                 struct smb2_transform_hdr *thdr =
 165                         (struct smb2_transform_hdr *)buf;
 166                 struct cifs_ses *ses = NULL;
 167                 struct list_head *tmp;
 168
 169                 /* decrypt frame now that it is completely read in */
 170                 spin_lock(&cifs_tcp_ses_lock);
 171                 list_for_each(tmp, &srvr->smb_ses_list) {
 172                         ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 173                         if (ses->Suid == thdr->SessionId)
 174                                 break;
 175
 176                         ses = NULL;
 177                 }
 178                 spin_unlock(&cifs_tcp_ses_lock);
 179                 if (ses == NULL) {
 180                         cifs_dbg(VFS, "no decryption - session id not found\n");
 181                         return 1;
 182                 }
 183         }
 184
 185         mid = le64_to_cpu(shdr->MessageId);
 186         if (len < pdu_size) {
 187                 if ((len >= hdr_size)
 188                     && (shdr->Status != 0)) {
 189                         pdu->StructureSize2 = 0;
 190                         /*
 191                          * As with SMB/CIFS, on some error cases servers may
 192                          * not return wct properly
 193                          */
 194                         return 0;
 195                 } else {
 196                         cifs_dbg(VFS, "Length less than SMB header size\n");
 197                 }
 198                 return 1;
 199         }
 200         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 201                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 202                          mid);
 203                 return 1;
 204         }
 205
 206         if (check_smb2_hdr(shdr, mid))
 207                 return 1;
 208
 209         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 210                 cifs_dbg(VFS, "Invalid structure size %u\n",
 211                          le16_to_cpu(shdr->StructureSize));
 212                 return 1;
 213         }
 214
 215         command = le16_to_cpu(shdr->Command);
 216         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 217                 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
 218                 return 1;
 219         }
 220
 221         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 222                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 223                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
 224                         /* error packets have 9 byte structure size */
 225                         cifs_dbg(VFS, "Invalid response size %u for command %d\n",
 226                                  le16_to_cpu(pdu->StructureSize2), command);
 227                         return 1;
 228                 } else if (command == SMB2_OPLOCK_BREAK_HE
 229                            && (shdr->Status == 0)
 230                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 231                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 232                         /* special case for SMB2.1 lease break message */
 233                         cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
 234                                  le16_to_cpu(pdu->StructureSize2));
 235                         return 1;
 236                 }
 237         }
 238
 239         clc_len = smb2_calc_size(buf, srvr);
 240
 241         if (shdr->Command == SMB2_NEGOTIATE)
 242                 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
 243
 244         if (len != clc_len) {
 245                 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
 246                          clc_len, len, mid);
 247                 /* create failed on symlink */
 248                 if (command == SMB2_CREATE_HE &&
 249                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 250                         return 0;
 251                 /* Windows 7 server returns 24 bytes more */
 252                 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 253                         return 0;
 254                 /* server can return one byte more due to implied bcc[0] */
 255                 if (clc_len == len + 1)
 256                         return 0;
 257
 258                 /*
 259                  * Some windows servers (win2016) will pad also the final
 260                  * PDU in a compound to 8 bytes.
 261                  */
 262                 if (((clc_len + 7) & ~7) == len)
 263                         return 0;
 264
 265                 /*
 266                  * MacOS server pads after SMB2.1 write response with 3 bytes
 267                  * of junk. Other servers match RFC1001 len to actual
 268                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 269                  * Some windows servers also pad up to 8 bytes when compounding.
 270                  */
 271                 if (clc_len < len)
 272                         return 0;
 273
 274                 pr_warn_once(
 275                         "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
 276                         len, clc_len, command, mid);
 277
 278                 return 1;
 279         }
 280         return 0;
 281 }
 282
 283 /*
 284  * The size of the variable area depends on the offset and length fields
 285  * located in different fields for various SMB2 responses. SMB2 responses
 286  * with no variable length info, show an offset of zero for the offset field.
 287  */
 288 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 289         /* SMB2_NEGOTIATE */ true,
 290         /* SMB2_SESSION_SETUP */ true,
 291         /* SMB2_LOGOFF */ false,
 292         /* SMB2_TREE_CONNECT */ false,
 293         /* SMB2_TREE_DISCONNECT */ false,
 294         /* SMB2_CREATE */ true,
 295         /* SMB2_CLOSE */ false,
 296         /* SMB2_FLUSH */ false,
 297         /* SMB2_READ */ true,
 298         /* SMB2_WRITE */ false,
 299         /* SMB2_LOCK */ false,
 300         /* SMB2_IOCTL */ true,
 301         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 302         /* SMB2_ECHO */ false,
 303         /* SMB2_QUERY_DIRECTORY */ true,
 304         /* SMB2_CHANGE_NOTIFY */ true,
 305         /* SMB2_QUERY_INFO */ true,
 306         /* SMB2_SET_INFO */ false,
 307         /* SMB2_OPLOCK_BREAK */ false
 308 };
 309
 310 /*
 311  * Returns the pointer to the beginning of the data area. Length of the data
 312  * area and the offset to it (from the beginning of the smb are also returned.
 313  */
 314 char *
 315 smb2_get_data_area_len(int *off, int *len, struct smb2_sync_hdr *shdr)
 316 {
 317         *off = 0;
 318         *len = 0;
 319
 320         /* error responses do not have data area */
 321         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 322             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 323                                                 SMB2_ERROR_STRUCTURE_SIZE2)
 324                 return NULL;
 325
 326         /*
 327          * Following commands have data areas so we have to get the location
 328          * of the data buffer offset and data buffer length for the particular
 329          * command.
 330          */
 331         switch (shdr->Command) {
 332         case SMB2_NEGOTIATE:
 333                 *off = le16_to_cpu(
 334                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 335                 *len = le16_to_cpu(
 336                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 337                 break;
 338         case SMB2_SESSION_SETUP:
 339                 *off = le16_to_cpu(
 340                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 341                 *len = le16_to_cpu(
 342                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 343                 break;
 344         case SMB2_CREATE:
 345                 *off = le32_to_cpu(
 346                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 347                 *len = le32_to_cpu(
 348                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 349                 break;
 350         case SMB2_QUERY_INFO:
 351                 *off = le16_to_cpu(
 352                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 353                 *len = le32_to_cpu(
 354                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 355                 break;
 356         case SMB2_READ:
 357                 /* TODO: is this a bug ? */
 358                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 359                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 360                 break;
 361         case SMB2_QUERY_DIRECTORY:
 362                 *off = le16_to_cpu(
 363                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 364                 *len = le32_to_cpu(
 365                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 366                 break;
 367         case SMB2_IOCTL:
 368                 *off = le32_to_cpu(
 369                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 370                 *len = le32_to_cpu(
 371                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 372                 break;
 373         case SMB2_CHANGE_NOTIFY:
 374                 *off = le16_to_cpu(
 375                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
 376                 *len = le32_to_cpu(
 377                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
 378                 break;
 379         default:
 380                 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
 381                 break;
 382         }
 383
 384         /*
 385          * Invalid length or offset probably means data area is invalid, but
 386          * we have little choice but to ignore the data area in this case.
 387          */
 388         if (*off > 4096) {
 389                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 390                 *len = 0;
 391                 *off = 0;
 392         } else if (*off < 0) {
 393                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 394                          *off);
 395                 *off = 0;
 396                 *len = 0;
 397         } else if (*len < 0) {
 398                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 399                          *len);
 400                 *len = 0;
 401         } else if (*len > 128 * 1024) {
 402                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 403                 *len = 0;
 404         }
 405
 406         /* return pointer to beginning of data area, ie offset from SMB start */
 407         if ((*off != 0) && (*len != 0))
 408                 return (char *)shdr + *off;
 409         else
 410                 return NULL;
 411 }
 412
 413 /*
 414  * Calculate the size of the SMB message based on the fixed header
 415  * portion, the number of word parameters and the data portion of the message.
 416  */
 417 unsigned int
 418 smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 419 {
 420         struct smb2_sync_pdu *pdu = (struct smb2_sync_pdu *)buf;
 421         struct smb2_sync_hdr *shdr = &pdu->sync_hdr;
 422         int offset; /* the offset from the beginning of SMB to data area */
 423         int data_length; /* the length of the variable length data area */
 424         /* Structure Size has already been checked to make sure it is 64 */
 425         int len = le16_to_cpu(shdr->StructureSize);
 426
 427         /*
 428          * StructureSize2, ie length of fixed parameter area has already
 429          * been checked to make sure it is the correct length.
 430          */
 431         len += le16_to_cpu(pdu->StructureSize2);
 432
 433         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 434                 goto calc_size_exit;
 435
 436         smb2_get_data_area_len(&offset, &data_length, shdr);
 437         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 438
 439         if (data_length > 0) {
 440                 /*
 441                  * Check to make sure that data area begins after fixed area,
 442                  * Note that last byte of the fixed area is part of data area
 443                  * for some commands, typically those with odd StructureSize,
 444                  * so we must add one to the calculation.
 445                  */
 446                 if (offset + 1 < len) {
 447                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
 448                                  offset + 1, len);
 449                         data_length = 0;
 450                 } else {
 451                         len = offset + data_length;
 452                 }
 453         }
 454 calc_size_exit:
 455         cifs_dbg(FYI, "SMB2 len %d\n", len);
 456         return len;
 457 }
 458
 459 /* Note: caller must free return buffer */
 460 __le16 *
 461 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 462 {
 463         int len;
 464         const char *start_of_path;
 465         __le16 *to;
 466         int map_type;
 467
 468         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 469                 map_type = SFM_MAP_UNI_RSVD;
 470         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 471                 map_type = SFU_MAP_UNI_RSVD;
 472         else
 473                 map_type = NO_MAP_UNI_RSVD;
 474
 475         /* Windows doesn't allow paths beginning with \ */
 476         if (from[0] == '\\')
 477                 start_of_path = from + 1;
 478
 479         /* SMB311 POSIX extensions paths do not include leading slash */
 480         else if (cifs_sb_master_tlink(cifs_sb) &&
 481                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 482                  (from[0] == '/')) {
 483                 start_of_path = from + 1;
 484         } else
 485                 start_of_path = from;
 486
 487         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 488                                    cifs_sb->local_nls, map_type);
 489         return to;
 490 }
 491
 492 __le32
 493 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 494 {
 495         __le32 lease = 0;
 496
 497         if (CIFS_CACHE_WRITE(cinode))
 498                 lease |= SMB2_LEASE_WRITE_CACHING;
 499         if (CIFS_CACHE_HANDLE(cinode))
 500                 lease |= SMB2_LEASE_HANDLE_CACHING;
 501         if (CIFS_CACHE_READ(cinode))
 502                 lease |= SMB2_LEASE_READ_CACHING;
 503         return lease;
 504 }
 505
 506 struct smb2_lease_break_work {
 507         struct work_struct lease_break;
 508         struct tcon_link *tlink;
 509         __u8 lease_key[16];
 510         __le32 lease_state;
 511 };
 512
 513 static void
 514 cifs_ses_oplock_break(struct work_struct *work)
 515 {
 516         struct smb2_lease_break_work *lw = container_of(work,
 517                                 struct smb2_lease_break_work, lease_break);
 518         int rc = 0;
 519
 520         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 521                               lw->lease_state);
 522
 523         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 524         cifs_put_tlink(lw->tlink);
 525         kfree(lw);
 526 }
 527
 528 static void
 529 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
 530                               __le32 new_lease_state)
 531 {
 532         struct smb2_lease_break_work *lw;
 533
 534         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 535         if (!lw) {
 536                 cifs_put_tlink(tlink);
 537                 return;
 538         }
 539
 540         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 541         lw->tlink = tlink;
 542         lw->lease_state = new_lease_state;
 543         memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
 544         queue_work(cifsiod_wq, &lw->lease_break);
 545 }
 546
 547 static bool
 548 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 549 {
 550         __u8 lease_state;
 551         struct list_head *tmp;
 552         struct cifsFileInfo *cfile;
 553         struct cifsInodeInfo *cinode;
 554         int ack_req = le32_to_cpu(rsp->Flags &
 555                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 556
 557         lease_state = le32_to_cpu(rsp->NewLeaseState);
 558
 559         list_for_each(tmp, &tcon->openFileList) {
 560                 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
 561                 cinode = CIFS_I(d_inode(cfile->dentry));
 562
 563                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 564                                                         SMB2_LEASE_KEY_SIZE))
 565                         continue;
 566
 567                 cifs_dbg(FYI, "found in the open list\n");
 568                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 569                          lease_state);
 570
 571                 if (ack_req)
 572                         cfile->oplock_break_cancelled = false;
 573                 else
 574                         cfile->oplock_break_cancelled = true;
 575
 576                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 577
 578                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 579                 cfile->oplock_level = lease_state;
 580
 581                 cifs_queue_oplock_break(cfile);
 582                 return true;
 583         }
 584
 585         return false;
 586 }
 587
 588 static struct cifs_pending_open *
 589 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
 590                                   struct smb2_lease_break *rsp)
 591 {
 592         __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
 593         int ack_req = le32_to_cpu(rsp->Flags &
 594                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 595         struct cifs_pending_open *open;
 596         struct cifs_pending_open *found = NULL;
 597
 598         list_for_each_entry(open, &tcon->pending_opens, olist) {
 599                 if (memcmp(open->lease_key, rsp->LeaseKey,
 600                            SMB2_LEASE_KEY_SIZE))
 601                         continue;
 602
 603                 if (!found && ack_req) {
 604                         found = open;
 605                 }
 606
 607                 cifs_dbg(FYI, "found in the pending open list\n");
 608                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 609                          lease_state);
 610
 611                 open->oplock = lease_state;
 612         }
 613
 614         return found;
 615 }
 616
 617 static bool
 618 smb2_is_valid_lease_break(char *buffer)
 619 {
 620         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 621         struct list_head *tmp, *tmp1, *tmp2;
 622         struct TCP_Server_Info *server;
 623         struct cifs_ses *ses;
 624         struct cifs_tcon *tcon;
 625         struct cifs_pending_open *open;
 626
 627         cifs_dbg(FYI, "Checking for lease break\n");
 628
 629         /* look up tcon based on tid & uid */
 630         spin_lock(&cifs_tcp_ses_lock);
 631         list_for_each(tmp, &cifs_tcp_ses_list) {
 632                 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 633
 634                 list_for_each(tmp1, &server->smb_ses_list) {
 635                         ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 636
 637                         list_for_each(tmp2, &ses->tcon_list) {
 638                                 tcon = list_entry(tmp2, struct cifs_tcon,
 639                                                   tcon_list);
 640                                 spin_lock(&tcon->open_file_lock);
 641                                 cifs_stats_inc(
 642                                     &tcon->stats.cifs_stats.num_oplock_brks);
 643                                 if (smb2_tcon_has_lease(tcon, rsp)) {
 644                                         spin_unlock(&tcon->open_file_lock);
 645                                         spin_unlock(&cifs_tcp_ses_lock);
 646                                         return true;
 647                                 }
 648                                 open = smb2_tcon_find_pending_open_lease(tcon,
 649                                                                          rsp);
 650                                 if (open) {
 651                                         __u8 lease_key[SMB2_LEASE_KEY_SIZE];
 652                                         struct tcon_link *tlink;
 653
 654                                         tlink = cifs_get_tlink(open->tlink);
 655                                         memcpy(lease_key, open->lease_key,
 656                                                SMB2_LEASE_KEY_SIZE);
 657                                         spin_unlock(&tcon->open_file_lock);
 658                                         spin_unlock(&cifs_tcp_ses_lock);
 659                                         smb2_queue_pending_open_break(tlink,
 660                                                                       lease_key,
 661                                                                       rsp->NewLeaseState);
 662                                         return true;
 663                                 }
 664                                 spin_unlock(&tcon->open_file_lock);
 665
 666                                 if (tcon->crfid.is_valid &&
 667                                     !memcmp(rsp->LeaseKey,
 668                                             tcon->crfid.fid->lease_key,
 669                                             SMB2_LEASE_KEY_SIZE)) {
 670                                         INIT_WORK(&tcon->crfid.lease_break,
 671                                                   smb2_cached_lease_break);
 672                                         queue_work(cifsiod_wq,
 673                                                    &tcon->crfid.lease_break);
 674                                         spin_unlock(&cifs_tcp_ses_lock);
 675                                         return true;
 676                                 }
 677                         }
 678                 }
 679         }
 680         spin_unlock(&cifs_tcp_ses_lock);
 681         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 682         return false;
 683 }
 684
 685 bool
 686 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 687 {
 688         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 689         struct list_head *tmp, *tmp1, *tmp2;
 690         struct cifs_ses *ses;
 691         struct cifs_tcon *tcon;
 692         struct cifsInodeInfo *cinode;
 693         struct cifsFileInfo *cfile;
 694
 695         cifs_dbg(FYI, "Checking for oplock break\n");
 696
 697         if (rsp->sync_hdr.Command != SMB2_OPLOCK_BREAK)
 698                 return false;
 699
 700         if (rsp->StructureSize !=
 701                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 702                 if (le16_to_cpu(rsp->StructureSize) == 44)
 703                         return smb2_is_valid_lease_break(buffer);
 704                 else
 705                         return false;
 706         }
 707
 708         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 709
 710         /* look up tcon based on tid & uid */
 711         spin_lock(&cifs_tcp_ses_lock);
 712         list_for_each(tmp, &server->smb_ses_list) {
 713                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 714
 715                 list_for_each(tmp1, &ses->tcon_list) {
 716                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
 717
 718                         spin_lock(&tcon->open_file_lock);
 719                         list_for_each(tmp2, &tcon->openFileList) {
 720                                 cfile = list_entry(tmp2, struct cifsFileInfo,
 721                                                      tlist);
 722                                 if (rsp->PersistentFid !=
 723                                     cfile->fid.persistent_fid ||
 724                                     rsp->VolatileFid !=
 725                                     cfile->fid.volatile_fid)
 726                                         continue;
 727
 728                                 cifs_dbg(FYI, "file id match, oplock break\n");
 729                                 cifs_stats_inc(
 730                                     &tcon->stats.cifs_stats.num_oplock_brks);
 731                                 cinode = CIFS_I(d_inode(cfile->dentry));
 732                                 spin_lock(&cfile->file_info_lock);
 733                                 if (!CIFS_CACHE_WRITE(cinode) &&
 734                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 735                                         cfile->oplock_break_cancelled = true;
 736                                 else
 737                                         cfile->oplock_break_cancelled = false;
 738
 739                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 740                                         &cinode->flags);
 741
 742                                 cfile->oplock_epoch = 0;
 743                                 cfile->oplock_level = rsp->OplockLevel;
 744
 745                                 spin_unlock(&cfile->file_info_lock);
 746
 747                                 cifs_queue_oplock_break(cfile);
 748
 749                                 spin_unlock(&tcon->open_file_lock);
 750                                 spin_unlock(&cifs_tcp_ses_lock);
 751                                 return true;
 752                         }
 753                         spin_unlock(&tcon->open_file_lock);
 754                 }
 755         }
 756         spin_unlock(&cifs_tcp_ses_lock);
 757         cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
 758         return false;
 759 }
 760
 761 void
 762 smb2_cancelled_close_fid(struct work_struct *work)
 763 {
 764         struct close_cancelled_open *cancelled = container_of(work,
 765                                         struct close_cancelled_open, work);
 766         struct cifs_tcon *tcon = cancelled->tcon;
 767         int rc;
 768
 769         if (cancelled->mid)
 770                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llx\n",
 771                               cancelled->mid);
 772         else
 773                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
 774
 775         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
 776                         cancelled->fid.volatile_fid);
 777         if (rc)
 778                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 779
 780         cifs_put_tcon(tcon);
 781         kfree(cancelled);
 782 }
 783
 784 /*
 785  * Caller should already has an extra reference to @tcon
 786  * This function is used to queue work to close a handle to prevent leaks
 787  * on the server.
 788  * We handle two cases. If an open was interrupted after we sent the
 789  * SMB2_CREATE to the server but before we processed the reply, and second
 790  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
 791  */
 792 static int
 793 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 794                             __u64 persistent_fid, __u64 volatile_fid)
 795 {
 796         struct close_cancelled_open *cancelled;
 797
 798         cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
 799         if (!cancelled)
 800                 return -ENOMEM;
 801
 802         cancelled->fid.persistent_fid = persistent_fid;
 803         cancelled->fid.volatile_fid = volatile_fid;
 804         cancelled->tcon = tcon;
 805         cancelled->cmd = cmd;
 806         cancelled->mid = mid;
 807         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 808         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
 809
 810         return 0;
 811 }
 812
 813 int
 814 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 815                             __u64 volatile_fid)
 816 {
 817         int rc;
 818
 819         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 820         spin_lock(&cifs_tcp_ses_lock);
 821         if (tcon->tc_count <= 0) {
 822                 struct TCP_Server_Info *server = NULL;
 823
 824                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 825                 spin_unlock(&cifs_tcp_ses_lock);
 826
 827                 if (tcon->ses)
 828                         server = tcon->ses->server;
 829
 830                 cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
 831                                 tcon->tid, persistent_fid, volatile_fid);
 832
 833                 return 0;
 834         }
 835         tcon->tc_count++;
 836         spin_unlock(&cifs_tcp_ses_lock);
 837
 838         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 839                                          persistent_fid, volatile_fid);
 840         if (rc)
 841                 cifs_put_tcon(tcon);
 842
 843         return rc;
 844 }
 845
 846 int
 847 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
 848 {
 849         struct smb2_sync_hdr *sync_hdr = (struct smb2_sync_hdr *)buffer;
 850         struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
 851         struct cifs_tcon *tcon;
 852         int rc;
 853
 854         if (sync_hdr->Command != SMB2_CREATE ||
 855             sync_hdr->Status != STATUS_SUCCESS)
 856                 return 0;
 857
 858         tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
 859                                   sync_hdr->TreeId);
 860         if (!tcon)
 861                 return -ENOENT;
 862
 863         rc = __smb2_handle_cancelled_cmd(tcon,
 864                                          le16_to_cpu(sync_hdr->Command),
 865                                          le64_to_cpu(sync_hdr->MessageId),
 866                                          rsp->PersistentFileId,
 867                                          rsp->VolatileFileId);
 868         if (rc)
 869                 cifs_put_tcon(tcon);
 870
 871         return rc;
 872 }
 873
 874 /**
 875  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 876  *
 877  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 878  * SMB2 header.
 879  *
 880  * @ses:        server session structure
 881  * @iov:        array containing the SMB request we will send to the server
 882  * @nvec:       number of array entries for the iov
 883  */
 884 int
 885 smb311_update_preauth_hash(struct cifs_ses *ses, struct kvec *iov, int nvec)
 886 {
 887         int i, rc;
 888         struct sdesc *d;
 889         struct smb2_sync_hdr *hdr;
 890         struct TCP_Server_Info *server = cifs_ses_server(ses);
 891
 892         hdr = (struct smb2_sync_hdr *)iov[0].iov_base;
 893         /* neg prot are always taken */
 894         if (hdr->Command == SMB2_NEGOTIATE)
 895                 goto ok;
 896
 897         /*
 898          * If we process a command which wasn't a negprot it means the
 899          * neg prot was already done, so the server dialect was set
 900          * and we can test it. Preauth requires 3.1.1 for now.
 901          */
 902         if (server->dialect != SMB311_PROT_ID)
 903                 return 0;
 904
 905         if (hdr->Command != SMB2_SESSION_SETUP)
 906                 return 0;
 907
 908         /* skip last sess setup response */
 909         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 910             && (hdr->Status == NT_STATUS_OK
 911                 || (hdr->Status !=
 912                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
 913                 return 0;
 914
 915 ok:
 916         rc = smb311_crypto_shash_allocate(server);
 917         if (rc)
 918                 return rc;
 919
 920         d = server->secmech.sdescsha512;
 921         rc = crypto_shash_init(&d->shash);
 922         if (rc) {
 923                 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
 924                 return rc;
 925         }
 926
 927         rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
 928                                  SMB2_PREAUTH_HASH_SIZE);
 929         if (rc) {
 930                 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
 931                 return rc;
 932         }
 933
 934         for (i = 0; i < nvec; i++) {
 935                 rc = crypto_shash_update(&d->shash,
 936                                          iov[i].iov_base, iov[i].iov_len);
 937                 if (rc) {
 938                         cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
 939                                  __func__);
 940                         return rc;
 941                 }
 942         }
 943
 944         rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
 945         if (rc) {
 946                 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
 947                          __func__);
 948                 return rc;
 949         }
 950
 951         return 0;
 952 }