fs/cifs/smb2misc.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002,2011
   5  *                 Etersoft, 2012
   6  *   Author(s): Steve French (sfrench@us.ibm.com)
   7  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
   8  *
   9  */
  10 #include <linux/ctype.h>
  11 #include "cifsglob.h"
  12 #include "cifsproto.h"
  13 #include "smb2proto.h"
  14 #include "cifs_debug.h"
  15 #include "cifs_unicode.h"
  16 #include "smb2status.h"
  17 #include "smb2glob.h"
  18 #include "nterr.h"
  19
  20 static int
  21 check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
  22 {
  23         __u64 wire_mid = le64_to_cpu(shdr->MessageId);
  24
  25         /*
  26          * Make sure that this really is an SMB, that it is a response,
  27          * and that the message ids match.
  28          */
  29         if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
  30             (mid == wire_mid)) {
  31                 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
  32                         return 0;
  33                 else {
  34                         /* only one valid case where server sends us request */
  35                         if (shdr->Command == SMB2_OPLOCK_BREAK)
  36                                 return 0;
  37                         else
  38                                 cifs_dbg(VFS, "Received Request not response\n");
  39                 }
  40         } else { /* bad signature or mid */
  41                 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
  42                         cifs_dbg(VFS, "Bad protocol string signature header %x\n",
  43                                  le32_to_cpu(shdr->ProtocolId));
  44                 if (mid != wire_mid)
  45                         cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
  46                                  mid, wire_mid);
  47         }
  48         cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
  49         return 1;
  50 }
  51
  52 /*
  53  *  The following table defines the expected "StructureSize" of SMB2 responses
  54  *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
  55  *
  56  *  Note that commands are defined in smb2pdu.h in le16 but the array below is
  57  *  indexed by command in host byte order
  58  */
  59 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
  60         /* SMB2_NEGOTIATE */ cpu_to_le16(65),
  61         /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
  62         /* SMB2_LOGOFF */ cpu_to_le16(4),
  63         /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
  64         /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
  65         /* SMB2_CREATE */ cpu_to_le16(89),
  66         /* SMB2_CLOSE */ cpu_to_le16(60),
  67         /* SMB2_FLUSH */ cpu_to_le16(4),
  68         /* SMB2_READ */ cpu_to_le16(17),
  69         /* SMB2_WRITE */ cpu_to_le16(17),
  70         /* SMB2_LOCK */ cpu_to_le16(4),
  71         /* SMB2_IOCTL */ cpu_to_le16(49),
  72         /* BB CHECK this ... not listed in documentation */
  73         /* SMB2_CANCEL */ cpu_to_le16(0),
  74         /* SMB2_ECHO */ cpu_to_le16(4),
  75         /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
  76         /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
  77         /* SMB2_QUERY_INFO */ cpu_to_le16(9),
  78         /* SMB2_SET_INFO */ cpu_to_le16(2),
  79         /* BB FIXME can also be 44 for lease break */
  80         /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
  81 };
  82
  83 #define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
  84
  85 static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
  86                               __u32 non_ctxlen)
  87 {
  88         __u16 neg_count;
  89         __u32 nc_offset, size_of_pad_before_neg_ctxts;
  90         struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
  91
  92         /* Negotiate contexts are only valid for latest dialect SMB3.11 */
  93         neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
  94         if ((neg_count == 0) ||
  95            (pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
  96                 return 0;
  97
  98         /*
  99          * if SPNEGO blob present (ie the RFC2478 GSS info which indicates
 100          * which security mechanisms the server supports) make sure that
 101          * the negotiate contexts start after it
 102          */
 103         nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
 104         /*
 105          * non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
 106          * and the latter is 1 byte bigger than the fix-sized area of the
 107          * NEGOTIATE response
 108          */
 109         if (nc_offset + 1 < non_ctxlen) {
 110                 pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
 111                 return 0;
 112         } else if (nc_offset + 1 == non_ctxlen) {
 113                 cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
 114                 size_of_pad_before_neg_ctxts = 0;
 115         } else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE)
 116                 /* has padding, but no SPNEGO blob */
 117                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
 118         else
 119                 size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
 120
 121         /* Verify that at least minimal negotiate contexts fit within frame */
 122         if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
 123                 pr_warn_once("negotiate context goes beyond end\n");
 124                 return 0;
 125         }
 126
 127         cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
 128                 len - nc_offset, size_of_pad_before_neg_ctxts);
 129
 130         /* length of negcontexts including pad from end of sec blob to them */
 131         return (len - nc_offset) + size_of_pad_before_neg_ctxts;
 132 }
 133
 134 int
 135 smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *srvr)
 136 {
 137         struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
 138         struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
 139         __u64 mid;
 140         __u32 clc_len;  /* calculated length */
 141         int command;
 142         int pdu_size = sizeof(struct smb2_pdu);
 143         int hdr_size = sizeof(struct smb2_hdr);
 144
 145         /*
 146          * Add function to do table lookup of StructureSize by command
 147          * ie Validate the wct via smb2_struct_sizes table above
 148          */
 149         if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
 150                 struct smb2_transform_hdr *thdr =
 151                         (struct smb2_transform_hdr *)buf;
 152                 struct cifs_ses *ses = NULL;
 153
 154                 /* decrypt frame now that it is completely read in */
 155                 spin_lock(&cifs_tcp_ses_lock);
 156                 list_for_each_entry(ses, &srvr->smb_ses_list, smb_ses_list) {
 157                         if (ses->Suid == le64_to_cpu(thdr->SessionId))
 158                                 break;
 159                 }
 160                 spin_unlock(&cifs_tcp_ses_lock);
 161                 if (list_entry_is_head(ses, &srvr->smb_ses_list,
 162                                        smb_ses_list)) {
 163                         cifs_dbg(VFS, "no decryption - session id not found\n");
 164                         return 1;
 165                 }
 166         }
 167
 168         mid = le64_to_cpu(shdr->MessageId);
 169         if (len < pdu_size) {
 170                 if ((len >= hdr_size)
 171                     && (shdr->Status != 0)) {
 172                         pdu->StructureSize2 = 0;
 173                         /*
 174                          * As with SMB/CIFS, on some error cases servers may
 175                          * not return wct properly
 176                          */
 177                         return 0;
 178                 } else {
 179                         cifs_dbg(VFS, "Length less than SMB header size\n");
 180                 }
 181                 return 1;
 182         }
 183         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
 184                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
 185                          mid);
 186                 return 1;
 187         }
 188
 189         if (check_smb2_hdr(shdr, mid))
 190                 return 1;
 191
 192         if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
 193                 cifs_dbg(VFS, "Invalid structure size %u\n",
 194                          le16_to_cpu(shdr->StructureSize));
 195                 return 1;
 196         }
 197
 198         command = le16_to_cpu(shdr->Command);
 199         if (command >= NUMBER_OF_SMB2_COMMANDS) {
 200                 cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
 201                 return 1;
 202         }
 203
 204         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
 205                 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
 206                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
 207                         /* error packets have 9 byte structure size */
 208                         cifs_dbg(VFS, "Invalid response size %u for command %d\n",
 209                                  le16_to_cpu(pdu->StructureSize2), command);
 210                         return 1;
 211                 } else if (command == SMB2_OPLOCK_BREAK_HE
 212                            && (shdr->Status == 0)
 213                            && (le16_to_cpu(pdu->StructureSize2) != 44)
 214                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
 215                         /* special case for SMB2.1 lease break message */
 216                         cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
 217                                  le16_to_cpu(pdu->StructureSize2));
 218                         return 1;
 219                 }
 220         }
 221
 222         clc_len = smb2_calc_size(buf, srvr);
 223
 224         if (shdr->Command == SMB2_NEGOTIATE)
 225                 clc_len += get_neg_ctxt_len(shdr, len, clc_len);
 226
 227         if (len != clc_len) {
 228                 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
 229                          clc_len, len, mid);
 230                 /* create failed on symlink */
 231                 if (command == SMB2_CREATE_HE &&
 232                     shdr->Status == STATUS_STOPPED_ON_SYMLINK)
 233                         return 0;
 234                 /* Windows 7 server returns 24 bytes more */
 235                 if (clc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
 236                         return 0;
 237                 /* server can return one byte more due to implied bcc[0] */
 238                 if (clc_len == len + 1)
 239                         return 0;
 240
 241                 /*
 242                  * Some windows servers (win2016) will pad also the final
 243                  * PDU in a compound to 8 bytes.
 244                  */
 245                 if (((clc_len + 7) & ~7) == len)
 246                         return 0;
 247
 248                 /*
 249                  * MacOS server pads after SMB2.1 write response with 3 bytes
 250                  * of junk. Other servers match RFC1001 len to actual
 251                  * SMB2/SMB3 frame length (header + smb2 response specific data)
 252                  * Some windows servers also pad up to 8 bytes when compounding.
 253                  */
 254                 if (clc_len < len)
 255                         return 0;
 256
 257                 pr_warn_once(
 258                         "srv rsp too short, len %d not %d. cmd:%d mid:%llu\n",
 259                         len, clc_len, command, mid);
 260
 261                 return 1;
 262         }
 263         return 0;
 264 }
 265
 266 /*
 267  * The size of the variable area depends on the offset and length fields
 268  * located in different fields for various SMB2 responses. SMB2 responses
 269  * with no variable length info, show an offset of zero for the offset field.
 270  */
 271 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
 272         /* SMB2_NEGOTIATE */ true,
 273         /* SMB2_SESSION_SETUP */ true,
 274         /* SMB2_LOGOFF */ false,
 275         /* SMB2_TREE_CONNECT */ false,
 276         /* SMB2_TREE_DISCONNECT */ false,
 277         /* SMB2_CREATE */ true,
 278         /* SMB2_CLOSE */ false,
 279         /* SMB2_FLUSH */ false,
 280         /* SMB2_READ */ true,
 281         /* SMB2_WRITE */ false,
 282         /* SMB2_LOCK */ false,
 283         /* SMB2_IOCTL */ true,
 284         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
 285         /* SMB2_ECHO */ false,
 286         /* SMB2_QUERY_DIRECTORY */ true,
 287         /* SMB2_CHANGE_NOTIFY */ true,
 288         /* SMB2_QUERY_INFO */ true,
 289         /* SMB2_SET_INFO */ false,
 290         /* SMB2_OPLOCK_BREAK */ false
 291 };
 292
 293 /*
 294  * Returns the pointer to the beginning of the data area. Length of the data
 295  * area and the offset to it (from the beginning of the smb are also returned.
 296  */
 297 char *
 298 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
 299 {
 300         *off = 0;
 301         *len = 0;
 302
 303         /* error responses do not have data area */
 304         if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
 305             (((struct smb2_err_rsp *)shdr)->StructureSize) ==
 306                                                 SMB2_ERROR_STRUCTURE_SIZE2)
 307                 return NULL;
 308
 309         /*
 310          * Following commands have data areas so we have to get the location
 311          * of the data buffer offset and data buffer length for the particular
 312          * command.
 313          */
 314         switch (shdr->Command) {
 315         case SMB2_NEGOTIATE:
 316                 *off = le16_to_cpu(
 317                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
 318                 *len = le16_to_cpu(
 319                   ((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
 320                 break;
 321         case SMB2_SESSION_SETUP:
 322                 *off = le16_to_cpu(
 323                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
 324                 *len = le16_to_cpu(
 325                   ((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
 326                 break;
 327         case SMB2_CREATE:
 328                 *off = le32_to_cpu(
 329                     ((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
 330                 *len = le32_to_cpu(
 331                     ((struct smb2_create_rsp *)shdr)->CreateContextsLength);
 332                 break;
 333         case SMB2_QUERY_INFO:
 334                 *off = le16_to_cpu(
 335                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
 336                 *len = le32_to_cpu(
 337                     ((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
 338                 break;
 339         case SMB2_READ:
 340                 /* TODO: is this a bug ? */
 341                 *off = ((struct smb2_read_rsp *)shdr)->DataOffset;
 342                 *len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
 343                 break;
 344         case SMB2_QUERY_DIRECTORY:
 345                 *off = le16_to_cpu(
 346                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
 347                 *len = le32_to_cpu(
 348                   ((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
 349                 break;
 350         case SMB2_IOCTL:
 351                 *off = le32_to_cpu(
 352                   ((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
 353                 *len = le32_to_cpu(
 354                   ((struct smb2_ioctl_rsp *)shdr)->OutputCount);
 355                 break;
 356         case SMB2_CHANGE_NOTIFY:
 357                 *off = le16_to_cpu(
 358                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
 359                 *len = le32_to_cpu(
 360                   ((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
 361                 break;
 362         default:
 363                 cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
 364                 break;
 365         }
 366
 367         /*
 368          * Invalid length or offset probably means data area is invalid, but
 369          * we have little choice but to ignore the data area in this case.
 370          */
 371         if (*off > 4096) {
 372                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
 373                 *len = 0;
 374                 *off = 0;
 375         } else if (*off < 0) {
 376                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
 377                          *off);
 378                 *off = 0;
 379                 *len = 0;
 380         } else if (*len < 0) {
 381                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
 382                          *len);
 383                 *len = 0;
 384         } else if (*len > 128 * 1024) {
 385                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
 386                 *len = 0;
 387         }
 388
 389         /* return pointer to beginning of data area, ie offset from SMB start */
 390         if ((*off != 0) && (*len != 0))
 391                 return (char *)shdr + *off;
 392         else
 393                 return NULL;
 394 }
 395
 396 /*
 397  * Calculate the size of the SMB message based on the fixed header
 398  * portion, the number of word parameters and the data portion of the message.
 399  */
 400 unsigned int
 401 smb2_calc_size(void *buf, struct TCP_Server_Info *srvr)
 402 {
 403         struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
 404         struct smb2_hdr *shdr = &pdu->hdr;
 405         int offset; /* the offset from the beginning of SMB to data area */
 406         int data_length; /* the length of the variable length data area */
 407         /* Structure Size has already been checked to make sure it is 64 */
 408         int len = le16_to_cpu(shdr->StructureSize);
 409
 410         /*
 411          * StructureSize2, ie length of fixed parameter area has already
 412          * been checked to make sure it is the correct length.
 413          */
 414         len += le16_to_cpu(pdu->StructureSize2);
 415
 416         if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
 417                 goto calc_size_exit;
 418
 419         smb2_get_data_area_len(&offset, &data_length, shdr);
 420         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
 421
 422         if (data_length > 0) {
 423                 /*
 424                  * Check to make sure that data area begins after fixed area,
 425                  * Note that last byte of the fixed area is part of data area
 426                  * for some commands, typically those with odd StructureSize,
 427                  * so we must add one to the calculation.
 428                  */
 429                 if (offset + 1 < len) {
 430                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
 431                                  offset + 1, len);
 432                         data_length = 0;
 433                 } else {
 434                         len = offset + data_length;
 435                 }
 436         }
 437 calc_size_exit:
 438         cifs_dbg(FYI, "SMB2 len %d\n", len);
 439         return len;
 440 }
 441
 442 /* Note: caller must free return buffer */
 443 __le16 *
 444 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
 445 {
 446         int len;
 447         const char *start_of_path;
 448         __le16 *to;
 449         int map_type;
 450
 451         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
 452                 map_type = SFM_MAP_UNI_RSVD;
 453         else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
 454                 map_type = SFU_MAP_UNI_RSVD;
 455         else
 456                 map_type = NO_MAP_UNI_RSVD;
 457
 458         /* Windows doesn't allow paths beginning with \ */
 459         if (from[0] == '\\')
 460                 start_of_path = from + 1;
 461
 462         /* SMB311 POSIX extensions paths do not include leading slash */
 463         else if (cifs_sb_master_tlink(cifs_sb) &&
 464                  cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
 465                  (from[0] == '/')) {
 466                 start_of_path = from + 1;
 467         } else
 468                 start_of_path = from;
 469
 470         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
 471                                    cifs_sb->local_nls, map_type);
 472         return to;
 473 }
 474
 475 __le32
 476 smb2_get_lease_state(struct cifsInodeInfo *cinode)
 477 {
 478         __le32 lease = 0;
 479
 480         if (CIFS_CACHE_WRITE(cinode))
 481                 lease |= SMB2_LEASE_WRITE_CACHING;
 482         if (CIFS_CACHE_HANDLE(cinode))
 483                 lease |= SMB2_LEASE_HANDLE_CACHING;
 484         if (CIFS_CACHE_READ(cinode))
 485                 lease |= SMB2_LEASE_READ_CACHING;
 486         return lease;
 487 }
 488
 489 struct smb2_lease_break_work {
 490         struct work_struct lease_break;
 491         struct tcon_link *tlink;
 492         __u8 lease_key[16];
 493         __le32 lease_state;
 494 };
 495
 496 static void
 497 cifs_ses_oplock_break(struct work_struct *work)
 498 {
 499         struct smb2_lease_break_work *lw = container_of(work,
 500                                 struct smb2_lease_break_work, lease_break);
 501         int rc = 0;
 502
 503         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
 504                               lw->lease_state);
 505
 506         cifs_dbg(FYI, "Lease release rc %d\n", rc);
 507         cifs_put_tlink(lw->tlink);
 508         kfree(lw);
 509 }
 510
 511 static void
 512 smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
 513                               __le32 new_lease_state)
 514 {
 515         struct smb2_lease_break_work *lw;
 516
 517         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 518         if (!lw) {
 519                 cifs_put_tlink(tlink);
 520                 return;
 521         }
 522
 523         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 524         lw->tlink = tlink;
 525         lw->lease_state = new_lease_state;
 526         memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
 527         queue_work(cifsiod_wq, &lw->lease_break);
 528 }
 529
 530 static bool
 531 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
 532 {
 533         __u8 lease_state;
 534         struct cifsFileInfo *cfile;
 535         struct cifsInodeInfo *cinode;
 536         int ack_req = le32_to_cpu(rsp->Flags &
 537                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 538
 539         lease_state = le32_to_cpu(rsp->NewLeaseState);
 540
 541         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 542                 cinode = CIFS_I(d_inode(cfile->dentry));
 543
 544                 if (memcmp(cinode->lease_key, rsp->LeaseKey,
 545                                                         SMB2_LEASE_KEY_SIZE))
 546                         continue;
 547
 548                 cifs_dbg(FYI, "found in the open list\n");
 549                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 550                          lease_state);
 551
 552                 if (ack_req)
 553                         cfile->oplock_break_cancelled = false;
 554                 else
 555                         cfile->oplock_break_cancelled = true;
 556
 557                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
 558
 559                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 560                 cfile->oplock_level = lease_state;
 561
 562                 cifs_queue_oplock_break(cfile);
 563                 return true;
 564         }
 565
 566         return false;
 567 }
 568
 569 static struct cifs_pending_open *
 570 smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
 571                                   struct smb2_lease_break *rsp)
 572 {
 573         __u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
 574         int ack_req = le32_to_cpu(rsp->Flags &
 575                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
 576         struct cifs_pending_open *open;
 577         struct cifs_pending_open *found = NULL;
 578
 579         list_for_each_entry(open, &tcon->pending_opens, olist) {
 580                 if (memcmp(open->lease_key, rsp->LeaseKey,
 581                            SMB2_LEASE_KEY_SIZE))
 582                         continue;
 583
 584                 if (!found && ack_req) {
 585                         found = open;
 586                 }
 587
 588                 cifs_dbg(FYI, "found in the pending open list\n");
 589                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 590                          lease_state);
 591
 592                 open->oplock = lease_state;
 593         }
 594
 595         return found;
 596 }
 597
 598 static bool
 599 smb2_is_valid_lease_break(char *buffer)
 600 {
 601         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 602         struct TCP_Server_Info *server;
 603         struct cifs_ses *ses;
 604         struct cifs_tcon *tcon;
 605         struct cifs_pending_open *open;
 606
 607         cifs_dbg(FYI, "Checking for lease break\n");
 608
 609         /* look up tcon based on tid & uid */
 610         spin_lock(&cifs_tcp_ses_lock);
 611         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
 612                 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
 613                         list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 614                                 spin_lock(&tcon->open_file_lock);
 615                                 cifs_stats_inc(
 616                                     &tcon->stats.cifs_stats.num_oplock_brks);
 617                                 if (smb2_tcon_has_lease(tcon, rsp)) {
 618                                         spin_unlock(&tcon->open_file_lock);
 619                                         spin_unlock(&cifs_tcp_ses_lock);
 620                                         return true;
 621                                 }
 622                                 open = smb2_tcon_find_pending_open_lease(tcon,
 623                                                                          rsp);
 624                                 if (open) {
 625                                         __u8 lease_key[SMB2_LEASE_KEY_SIZE];
 626                                         struct tcon_link *tlink;
 627
 628                                         tlink = cifs_get_tlink(open->tlink);
 629                                         memcpy(lease_key, open->lease_key,
 630                                                SMB2_LEASE_KEY_SIZE);
 631                                         spin_unlock(&tcon->open_file_lock);
 632                                         spin_unlock(&cifs_tcp_ses_lock);
 633                                         smb2_queue_pending_open_break(tlink,
 634                                                                       lease_key,
 635                                                                       rsp->NewLeaseState);
 636                                         return true;
 637                                 }
 638                                 spin_unlock(&tcon->open_file_lock);
 639
 640                                 if (tcon->crfid.is_valid &&
 641                                     !memcmp(rsp->LeaseKey,
 642                                             tcon->crfid.fid->lease_key,
 643                                             SMB2_LEASE_KEY_SIZE)) {
 644                                         tcon->crfid.time = 0;
 645                                         INIT_WORK(&tcon->crfid.lease_break,
 646                                                   smb2_cached_lease_break);
 647                                         queue_work(cifsiod_wq,
 648                                                    &tcon->crfid.lease_break);
 649                                         spin_unlock(&cifs_tcp_ses_lock);
 650                                         return true;
 651                                 }
 652                         }
 653                 }
 654         }
 655         spin_unlock(&cifs_tcp_ses_lock);
 656         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 657         return false;
 658 }
 659
 660 bool
 661 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 662 {
 663         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 664         struct cifs_ses *ses;
 665         struct cifs_tcon *tcon;
 666         struct cifsInodeInfo *cinode;
 667         struct cifsFileInfo *cfile;
 668
 669         cifs_dbg(FYI, "Checking for oplock break\n");
 670
 671         if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
 672                 return false;
 673
 674         if (rsp->StructureSize !=
 675                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 676                 if (le16_to_cpu(rsp->StructureSize) == 44)
 677                         return smb2_is_valid_lease_break(buffer);
 678                 else
 679                         return false;
 680         }
 681
 682         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 683
 684         /* look up tcon based on tid & uid */
 685         spin_lock(&cifs_tcp_ses_lock);
 686         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
 687                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 688
 689                         spin_lock(&tcon->open_file_lock);
 690                         list_for_each_entry(cfile, &tcon->openFileList, tlist) {
 691                                 if (rsp->PersistentFid !=
 692                                     cfile->fid.persistent_fid ||
 693                                     rsp->VolatileFid !=
 694                                     cfile->fid.volatile_fid)
 695                                         continue;
 696
 697                                 cifs_dbg(FYI, "file id match, oplock break\n");
 698                                 cifs_stats_inc(
 699                                     &tcon->stats.cifs_stats.num_oplock_brks);
 700                                 cinode = CIFS_I(d_inode(cfile->dentry));
 701                                 spin_lock(&cfile->file_info_lock);
 702                                 if (!CIFS_CACHE_WRITE(cinode) &&
 703                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 704                                         cfile->oplock_break_cancelled = true;
 705                                 else
 706                                         cfile->oplock_break_cancelled = false;
 707
 708                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 709                                         &cinode->flags);
 710
 711                                 cfile->oplock_epoch = 0;
 712                                 cfile->oplock_level = rsp->OplockLevel;
 713
 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                 }
 724         }
 725         spin_unlock(&cifs_tcp_ses_lock);
 726         cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
 727         return true;
 728 }
 729
 730 void
 731 smb2_cancelled_close_fid(struct work_struct *work)
 732 {
 733         struct close_cancelled_open *cancelled = container_of(work,
 734                                         struct close_cancelled_open, work);
 735         struct cifs_tcon *tcon = cancelled->tcon;
 736         int rc;
 737
 738         if (cancelled->mid)
 739                 cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
 740                               cancelled->mid);
 741         else
 742                 cifs_tcon_dbg(VFS, "Close interrupted close\n");
 743
 744         rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
 745                         cancelled->fid.volatile_fid);
 746         if (rc)
 747                 cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
 748
 749         cifs_put_tcon(tcon);
 750         kfree(cancelled);
 751 }
 752
 753 /*
 754  * Caller should already has an extra reference to @tcon
 755  * This function is used to queue work to close a handle to prevent leaks
 756  * on the server.
 757  * We handle two cases. If an open was interrupted after we sent the
 758  * SMB2_CREATE to the server but before we processed the reply, and second
 759  * if a close was interrupted before we sent the SMB2_CLOSE to the server.
 760  */
 761 static int
 762 __smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
 763                             __u64 persistent_fid, __u64 volatile_fid)
 764 {
 765         struct close_cancelled_open *cancelled;
 766
 767         cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
 768         if (!cancelled)
 769                 return -ENOMEM;
 770
 771         cancelled->fid.persistent_fid = persistent_fid;
 772         cancelled->fid.volatile_fid = volatile_fid;
 773         cancelled->tcon = tcon;
 774         cancelled->cmd = cmd;
 775         cancelled->mid = mid;
 776         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 777         WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
 778
 779         return 0;
 780 }
 781
 782 int
 783 smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
 784                             __u64 volatile_fid)
 785 {
 786         int rc;
 787
 788         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
 789         spin_lock(&cifs_tcp_ses_lock);
 790         if (tcon->tc_count <= 0) {
 791                 struct TCP_Server_Info *server = NULL;
 792
 793                 WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
 794                 spin_unlock(&cifs_tcp_ses_lock);
 795
 796                 if (tcon->ses)
 797                         server = tcon->ses->server;
 798
 799                 cifs_server_dbg(FYI, "tid=%u: tcon is closing, skipping async close retry of fid %llu %llu\n",
 800                                 tcon->tid, persistent_fid, volatile_fid);
 801
 802                 return 0;
 803         }
 804         tcon->tc_count++;
 805         spin_unlock(&cifs_tcp_ses_lock);
 806
 807         rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
 808                                          persistent_fid, volatile_fid);
 809         if (rc)
 810                 cifs_put_tcon(tcon);
 811
 812         return rc;
 813 }
 814
 815 int
 816 smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 817 {
 818         struct smb2_hdr *hdr = mid->resp_buf;
 819         struct smb2_create_rsp *rsp = mid->resp_buf;
 820         struct cifs_tcon *tcon;
 821         int rc;
 822
 823         if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
 824             hdr->Status != STATUS_SUCCESS)
 825                 return 0;
 826
 827         tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
 828                                   le32_to_cpu(hdr->Id.SyncId.TreeId));
 829         if (!tcon)
 830                 return -ENOENT;
 831
 832         rc = __smb2_handle_cancelled_cmd(tcon,
 833                                          le16_to_cpu(hdr->Command),
 834                                          le64_to_cpu(hdr->MessageId),
 835                                          rsp->PersistentFileId,
 836                                          rsp->VolatileFileId);
 837         if (rc)
 838                 cifs_put_tcon(tcon);
 839
 840         return rc;
 841 }
 842
 843 /**
 844  * smb311_update_preauth_hash - update @ses hash with the packet data in @iov
 845  *
 846  * Assumes @iov does not contain the rfc1002 length and iov[0] has the
 847  * SMB2 header.
 848  *
 849  * @ses:        server session structure
 850  * @server:     pointer to server info
 851  * @iov:        array containing the SMB request we will send to the server
 852  * @nvec:       number of array entries for the iov
 853  */
 854 int
 855 smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
 856                            struct kvec *iov, int nvec)
 857 {
 858         int i, rc;
 859         struct sdesc *d;
 860         struct smb2_hdr *hdr;
 861
 862         hdr = (struct smb2_hdr *)iov[0].iov_base;
 863         /* neg prot are always taken */
 864         if (hdr->Command == SMB2_NEGOTIATE)
 865                 goto ok;
 866
 867         /*
 868          * If we process a command which wasn't a negprot it means the
 869          * neg prot was already done, so the server dialect was set
 870          * and we can test it. Preauth requires 3.1.1 for now.
 871          */
 872         if (server->dialect != SMB311_PROT_ID)
 873                 return 0;
 874
 875         if (hdr->Command != SMB2_SESSION_SETUP)
 876                 return 0;
 877
 878         /* skip last sess setup response */
 879         if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
 880             && (hdr->Status == NT_STATUS_OK
 881                 || (hdr->Status !=
 882                     cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
 883                 return 0;
 884
 885 ok:
 886         rc = smb311_crypto_shash_allocate(server);
 887         if (rc)
 888                 return rc;
 889
 890         d = server->secmech.sdescsha512;
 891         rc = crypto_shash_init(&d->shash);
 892         if (rc) {
 893                 cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
 894                 return rc;
 895         }
 896
 897         rc = crypto_shash_update(&d->shash, ses->preauth_sha_hash,
 898                                  SMB2_PREAUTH_HASH_SIZE);
 899         if (rc) {
 900                 cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
 901                 return rc;
 902         }
 903
 904         for (i = 0; i < nvec; i++) {
 905                 rc = crypto_shash_update(&d->shash,
 906                                          iov[i].iov_base, iov[i].iov_len);
 907                 if (rc) {
 908                         cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
 909                                  __func__);
 910                         return rc;
 911                 }
 912         }
 913
 914         rc = crypto_shash_final(&d->shash, ses->preauth_sha_hash);
 915         if (rc) {
 916                 cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
 917                          __func__);
 918                 return rc;
 919         }
 920
 921         return 0;
 922 }