fs/cifs/connect.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   3  *   fs/cifs/connect.c
   4  *
   5  *   Copyright (C) International Business Machines  Corp., 2002,2011
   6  *   Author(s): Steve French (sfrench@us.ibm.com)
   7  *
   8  */
   9 #include <linux/fs.h>
  10 #include <linux/net.h>
  11 #include <linux/string.h>
  12 #include <linux/sched/mm.h>
  13 #include <linux/sched/signal.h>
  14 #include <linux/list.h>
  15 #include <linux/wait.h>
  16 #include <linux/slab.h>
  17 #include <linux/pagemap.h>
  18 #include <linux/ctype.h>
  19 #include <linux/utsname.h>
  20 #include <linux/mempool.h>
  21 #include <linux/delay.h>
  22 #include <linux/completion.h>
  23 #include <linux/kthread.h>
  24 #include <linux/pagevec.h>
  25 #include <linux/freezer.h>
  26 #include <linux/namei.h>
  27 #include <linux/uuid.h>
  28 #include <linux/uaccess.h>
  29 #include <asm/processor.h>
  30 #include <linux/inet.h>
  31 #include <linux/module.h>
  32 #include <keys/user-type.h>
  33 #include <net/ipv6.h>
  34 #include <linux/parser.h>
  35 #include <linux/bvec.h>
  36 #include "cifspdu.h"
  37 #include "cifsglob.h"
  38 #include "cifsproto.h"
  39 #include "cifs_unicode.h"
  40 #include "cifs_debug.h"
  41 #include "cifs_fs_sb.h"
  42 #include "ntlmssp.h"
  43 #include "nterr.h"
  44 #include "rfc1002pdu.h"
  45 #include "fscache.h"
  46 #include "smb2proto.h"
  47 #include "smbdirect.h"
  48 #include "dns_resolve.h"
  49 #ifdef CONFIG_CIFS_DFS_UPCALL
  50 #include "dfs_cache.h"
  51 #endif
  52 #include "fs_context.h"
  53 #include "cifs_swn.h"
  54
  55 extern mempool_t *cifs_req_poolp;
  56 extern bool disable_legacy_dialects;
  57
  58 /* FIXME: should these be tunable? */
  59 #define TLINK_ERROR_EXPIRE      (1 * HZ)
  60 #define TLINK_IDLE_EXPIRE       (600 * HZ)
  61
  62 /* Drop the connection to not overload the server */
  63 #define NUM_STATUS_IO_TIMEOUT   5
  64
  65 static int ip_connect(struct TCP_Server_Info *server);
  66 static int generic_ip_connect(struct TCP_Server_Info *server);
  67 static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
  68 static void cifs_prune_tlinks(struct work_struct *work);
  69
  70 /*
  71  * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
  72  * get their ip addresses changed at some point.
  73  *
  74  * This should be called with server->srv_mutex held.
  75  */
  76 static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
  77 {
  78         int rc;
  79         int len;
  80         char *unc, *ipaddr = NULL;
  81         time64_t expiry, now;
  82         unsigned long ttl = SMB_DNS_RESOLVE_INTERVAL_DEFAULT;
  83
  84         if (!server->hostname)
  85                 return -EINVAL;
  86
  87         len = strlen(server->hostname) + 3;
  88
  89         unc = kmalloc(len, GFP_KERNEL);
  90         if (!unc) {
  91                 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
  92                 return -ENOMEM;
  93         }
  94         scnprintf(unc, len, "\\\\%s", server->hostname);
  95
  96         rc = dns_resolve_server_name_to_ip(unc, &ipaddr, &expiry);
  97         kfree(unc);
  98
  99         if (rc < 0) {
 100                 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
 101                          __func__, server->hostname, rc);
 102                 goto requeue_resolve;
 103         }
 104
 105         spin_lock(&cifs_tcp_ses_lock);
 106         rc = cifs_convert_address((struct sockaddr *)&server->dstaddr, ipaddr,
 107                                   strlen(ipaddr));
 108         spin_unlock(&cifs_tcp_ses_lock);
 109         kfree(ipaddr);
 110
 111         /* rc == 1 means success here */
 112         if (rc) {
 113                 now = ktime_get_real_seconds();
 114                 if (expiry && expiry > now)
 115                         /*
 116                          * To make sure we don't use the cached entry, retry 1s
 117                          * after expiry.
 118                          */
 119                         ttl = (expiry - now + 1);
 120         }
 121         rc = !rc ? -1 : 0;
 122
 123 requeue_resolve:
 124         cifs_dbg(FYI, "%s: next dns resolution scheduled for %lu seconds in the future\n",
 125                  __func__, ttl);
 126         mod_delayed_work(cifsiod_wq, &server->resolve, (ttl * HZ));
 127
 128         return rc;
 129 }
 130
 131
 132 static void cifs_resolve_server(struct work_struct *work)
 133 {
 134         int rc;
 135         struct TCP_Server_Info *server = container_of(work,
 136                                         struct TCP_Server_Info, resolve.work);
 137
 138         mutex_lock(&server->srv_mutex);
 139
 140         /*
 141          * Resolve the hostname again to make sure that IP address is up-to-date.
 142          */
 143         rc = reconn_set_ipaddr_from_hostname(server);
 144         if (rc) {
 145                 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
 146                                 __func__, rc);
 147         }
 148
 149         mutex_unlock(&server->srv_mutex);
 150 }
 151
 152 #ifdef CONFIG_CIFS_DFS_UPCALL
 153 /* These functions must be called with server->srv_mutex held */
 154 static void reconn_set_next_dfs_target(struct TCP_Server_Info *server,
 155                                        struct cifs_sb_info *cifs_sb,
 156                                        struct dfs_cache_tgt_list *tgt_list,
 157                                        struct dfs_cache_tgt_iterator **tgt_it)
 158 {
 159         const char *name;
 160         int rc;
 161
 162         if (!cifs_sb || !cifs_sb->origin_fullpath)
 163                 return;
 164
 165         if (!*tgt_it) {
 166                 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
 167         } else {
 168                 *tgt_it = dfs_cache_get_next_tgt(tgt_list, *tgt_it);
 169                 if (!*tgt_it)
 170                         *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
 171         }
 172
 173         cifs_dbg(FYI, "%s: UNC: %s\n", __func__, cifs_sb->origin_fullpath);
 174
 175         name = dfs_cache_get_tgt_name(*tgt_it);
 176
 177         kfree(server->hostname);
 178
 179         server->hostname = extract_hostname(name);
 180         if (IS_ERR(server->hostname)) {
 181                 cifs_dbg(FYI,
 182                          "%s: failed to extract hostname from target: %ld\n",
 183                          __func__, PTR_ERR(server->hostname));
 184                 return;
 185         }
 186
 187         rc = reconn_set_ipaddr_from_hostname(server);
 188         if (rc) {
 189                 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
 190                          __func__, rc);
 191         }
 192 }
 193
 194 static inline int reconn_setup_dfs_targets(struct cifs_sb_info *cifs_sb,
 195                                            struct dfs_cache_tgt_list *tl)
 196 {
 197         if (!cifs_sb->origin_fullpath)
 198                 return -EOPNOTSUPP;
 199         return dfs_cache_noreq_find(cifs_sb->origin_fullpath + 1, NULL, tl);
 200 }
 201 #endif
 202
 203 /*
 204  * cifs tcp session reconnection
 205  *
 206  * mark tcp session as reconnecting so temporarily locked
 207  * mark all smb sessions as reconnecting for tcp session
 208  * reconnect tcp session
 209  * wake up waiters on reconnection? - (not needed currently)
 210  */
 211 int
 212 cifs_reconnect(struct TCP_Server_Info *server)
 213 {
 214         int rc = 0;
 215         struct list_head *tmp, *tmp2;
 216         struct cifs_ses *ses;
 217         struct cifs_tcon *tcon;
 218         struct mid_q_entry *mid_entry;
 219         struct list_head retry_list;
 220 #ifdef CONFIG_CIFS_DFS_UPCALL
 221         struct super_block *sb = NULL;
 222         struct cifs_sb_info *cifs_sb = NULL;
 223         struct dfs_cache_tgt_list tgt_list = DFS_CACHE_TGT_LIST_INIT(tgt_list);
 224         struct dfs_cache_tgt_iterator *tgt_it = NULL;
 225 #endif
 226
 227         spin_lock(&GlobalMid_Lock);
 228         server->nr_targets = 1;
 229 #ifdef CONFIG_CIFS_DFS_UPCALL
 230         spin_unlock(&GlobalMid_Lock);
 231         sb = cifs_get_tcp_super(server);
 232         if (IS_ERR(sb)) {
 233                 rc = PTR_ERR(sb);
 234                 cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n",
 235                          __func__, rc);
 236                 sb = NULL;
 237         } else {
 238                 cifs_sb = CIFS_SB(sb);
 239                 rc = reconn_setup_dfs_targets(cifs_sb, &tgt_list);
 240                 if (rc) {
 241                         cifs_sb = NULL;
 242                         if (rc != -EOPNOTSUPP) {
 243                                 cifs_server_dbg(VFS, "%s: no target servers for DFS failover\n",
 244                                                 __func__);
 245                         }
 246                 } else {
 247                         server->nr_targets = dfs_cache_get_nr_tgts(&tgt_list);
 248                 }
 249         }
 250         cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__,
 251                  server->nr_targets);
 252         spin_lock(&GlobalMid_Lock);
 253 #endif
 254         if (server->tcpStatus == CifsExiting) {
 255                 /* the demux thread will exit normally
 256                 next time through the loop */
 257                 spin_unlock(&GlobalMid_Lock);
 258 #ifdef CONFIG_CIFS_DFS_UPCALL
 259                 dfs_cache_free_tgts(&tgt_list);
 260                 cifs_put_tcp_super(sb);
 261 #endif
 262                 wake_up(&server->response_q);
 263                 return rc;
 264         } else
 265                 server->tcpStatus = CifsNeedReconnect;
 266         spin_unlock(&GlobalMid_Lock);
 267         server->maxBuf = 0;
 268         server->max_read = 0;
 269
 270         cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
 271         trace_smb3_reconnect(server->CurrentMid, server->conn_id, server->hostname);
 272
 273         /* before reconnecting the tcp session, mark the smb session (uid)
 274                 and the tid bad so they are not used until reconnected */
 275         cifs_dbg(FYI, "%s: marking sessions and tcons for reconnect\n",
 276                  __func__);
 277         spin_lock(&cifs_tcp_ses_lock);
 278         list_for_each(tmp, &server->smb_ses_list) {
 279                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 280                 ses->need_reconnect = true;
 281                 list_for_each(tmp2, &ses->tcon_list) {
 282                         tcon = list_entry(tmp2, struct cifs_tcon, tcon_list);
 283                         tcon->need_reconnect = true;
 284                 }
 285                 if (ses->tcon_ipc)
 286                         ses->tcon_ipc->need_reconnect = true;
 287         }
 288         spin_unlock(&cifs_tcp_ses_lock);
 289
 290         /* do not want to be sending data on a socket we are freeing */
 291         cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
 292         mutex_lock(&server->srv_mutex);
 293         if (server->ssocket) {
 294                 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n",
 295                          server->ssocket->state, server->ssocket->flags);
 296                 kernel_sock_shutdown(server->ssocket, SHUT_WR);
 297                 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n",
 298                          server->ssocket->state, server->ssocket->flags);
 299                 sock_release(server->ssocket);
 300                 server->ssocket = NULL;
 301         }
 302         server->sequence_number = 0;
 303         server->session_estab = false;
 304         kfree(server->session_key.response);
 305         server->session_key.response = NULL;
 306         server->session_key.len = 0;
 307         server->lstrp = jiffies;
 308
 309         /* mark submitted MIDs for retry and issue callback */
 310         INIT_LIST_HEAD(&retry_list);
 311         cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
 312         spin_lock(&GlobalMid_Lock);
 313         list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 314                 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 315                 kref_get(&mid_entry->refcount);
 316                 if (mid_entry->mid_state == MID_REQUEST_SUBMITTED)
 317                         mid_entry->mid_state = MID_RETRY_NEEDED;
 318                 list_move(&mid_entry->qhead, &retry_list);
 319                 mid_entry->mid_flags |= MID_DELETED;
 320         }
 321         spin_unlock(&GlobalMid_Lock);
 322         mutex_unlock(&server->srv_mutex);
 323
 324         cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
 325         list_for_each_safe(tmp, tmp2, &retry_list) {
 326                 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 327                 list_del_init(&mid_entry->qhead);
 328                 mid_entry->callback(mid_entry);
 329                 cifs_mid_q_entry_release(mid_entry);
 330         }
 331
 332         if (cifs_rdma_enabled(server)) {
 333                 mutex_lock(&server->srv_mutex);
 334                 smbd_destroy(server);
 335                 mutex_unlock(&server->srv_mutex);
 336         }
 337
 338         do {
 339                 try_to_freeze();
 340
 341                 mutex_lock(&server->srv_mutex);
 342
 343
 344                 if (!cifs_swn_set_server_dstaddr(server)) {
 345 #ifdef CONFIG_CIFS_DFS_UPCALL
 346                 if (cifs_sb && cifs_sb->origin_fullpath)
 347                         /*
 348                          * Set up next DFS target server (if any) for reconnect. If DFS
 349                          * feature is disabled, then we will retry last server we
 350                          * connected to before.
 351                          */
 352                         reconn_set_next_dfs_target(server, cifs_sb, &tgt_list, &tgt_it);
 353                 else {
 354 #endif
 355                         /*
 356                          * Resolve the hostname again to make sure that IP address is up-to-date.
 357                          */
 358                         rc = reconn_set_ipaddr_from_hostname(server);
 359                         if (rc) {
 360                                 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
 361                                                 __func__, rc);
 362                         }
 363
 364 #ifdef CONFIG_CIFS_DFS_UPCALL
 365                 }
 366 #endif
 367
 368
 369                 }
 370
 371                 if (cifs_rdma_enabled(server))
 372                         rc = smbd_reconnect(server);
 373                 else
 374                         rc = generic_ip_connect(server);
 375                 if (rc) {
 376                         cifs_dbg(FYI, "reconnect error %d\n", rc);
 377                         mutex_unlock(&server->srv_mutex);
 378                         msleep(3000);
 379                 } else {
 380                         atomic_inc(&tcpSesReconnectCount);
 381                         set_credits(server, 1);
 382                         spin_lock(&GlobalMid_Lock);
 383                         if (server->tcpStatus != CifsExiting)
 384                                 server->tcpStatus = CifsNeedNegotiate;
 385                         spin_unlock(&GlobalMid_Lock);
 386                         cifs_swn_reset_server_dstaddr(server);
 387                         mutex_unlock(&server->srv_mutex);
 388                 }
 389         } while (server->tcpStatus == CifsNeedReconnect);
 390
 391 #ifdef CONFIG_CIFS_DFS_UPCALL
 392         if (tgt_it) {
 393                 rc = dfs_cache_noreq_update_tgthint(cifs_sb->origin_fullpath + 1,
 394                                                     tgt_it);
 395                 if (rc) {
 396                         cifs_server_dbg(VFS, "%s: failed to update DFS target hint: rc = %d\n",
 397                                  __func__, rc);
 398                 }
 399                 dfs_cache_free_tgts(&tgt_list);
 400         }
 401
 402         cifs_put_tcp_super(sb);
 403 #endif
 404         if (server->tcpStatus == CifsNeedNegotiate)
 405                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 406
 407         wake_up(&server->response_q);
 408         return rc;
 409 }
 410
 411 static void
 412 cifs_echo_request(struct work_struct *work)
 413 {
 414         int rc;
 415         struct TCP_Server_Info *server = container_of(work,
 416                                         struct TCP_Server_Info, echo.work);
 417
 418         /*
 419          * We cannot send an echo if it is disabled.
 420          * Also, no need to ping if we got a response recently.
 421          */
 422
 423         if (server->tcpStatus == CifsNeedReconnect ||
 424             server->tcpStatus == CifsExiting ||
 425             server->tcpStatus == CifsNew ||
 426             (server->ops->can_echo && !server->ops->can_echo(server)) ||
 427             time_before(jiffies, server->lstrp + server->echo_interval - HZ))
 428                 goto requeue_echo;
 429
 430         rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
 431         if (rc)
 432                 cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
 433                          server->hostname);
 434
 435         /* Check witness registrations */
 436         cifs_swn_check();
 437
 438 requeue_echo:
 439         queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
 440 }
 441
 442 static bool
 443 allocate_buffers(struct TCP_Server_Info *server)
 444 {
 445         if (!server->bigbuf) {
 446                 server->bigbuf = (char *)cifs_buf_get();
 447                 if (!server->bigbuf) {
 448                         cifs_server_dbg(VFS, "No memory for large SMB response\n");
 449                         msleep(3000);
 450                         /* retry will check if exiting */
 451                         return false;
 452                 }
 453         } else if (server->large_buf) {
 454                 /* we are reusing a dirty large buf, clear its start */
 455                 memset(server->bigbuf, 0, HEADER_SIZE(server));
 456         }
 457
 458         if (!server->smallbuf) {
 459                 server->smallbuf = (char *)cifs_small_buf_get();
 460                 if (!server->smallbuf) {
 461                         cifs_server_dbg(VFS, "No memory for SMB response\n");
 462                         msleep(1000);
 463                         /* retry will check if exiting */
 464                         return false;
 465                 }
 466                 /* beginning of smb buffer is cleared in our buf_get */
 467         } else {
 468                 /* if existing small buf clear beginning */
 469                 memset(server->smallbuf, 0, HEADER_SIZE(server));
 470         }
 471
 472         return true;
 473 }
 474
 475 static bool
 476 server_unresponsive(struct TCP_Server_Info *server)
 477 {
 478         /*
 479          * We need to wait 3 echo intervals to make sure we handle such
 480          * situations right:
 481          * 1s  client sends a normal SMB request
 482          * 2s  client gets a response
 483          * 30s echo workqueue job pops, and decides we got a response recently
 484          *     and don't need to send another
 485          * ...
 486          * 65s kernel_recvmsg times out, and we see that we haven't gotten
 487          *     a response in >60s.
 488          */
 489         if ((server->tcpStatus == CifsGood ||
 490             server->tcpStatus == CifsNeedNegotiate) &&
 491             (!server->ops->can_echo || server->ops->can_echo(server)) &&
 492             time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
 493                 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
 494                          (3 * server->echo_interval) / HZ);
 495                 cifs_reconnect(server);
 496                 return true;
 497         }
 498
 499         return false;
 500 }
 501
 502 static inline bool
 503 zero_credits(struct TCP_Server_Info *server)
 504 {
 505         int val;
 506
 507         spin_lock(&server->req_lock);
 508         val = server->credits + server->echo_credits + server->oplock_credits;
 509         if (server->in_flight == 0 && val == 0) {
 510                 spin_unlock(&server->req_lock);
 511                 return true;
 512         }
 513         spin_unlock(&server->req_lock);
 514         return false;
 515 }
 516
 517 static int
 518 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 519 {
 520         int length = 0;
 521         int total_read;
 522
 523         smb_msg->msg_control = NULL;
 524         smb_msg->msg_controllen = 0;
 525
 526         for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
 527                 try_to_freeze();
 528
 529                 /* reconnect if no credits and no requests in flight */
 530                 if (zero_credits(server)) {
 531                         cifs_reconnect(server);
 532                         return -ECONNABORTED;
 533                 }
 534
 535                 if (server_unresponsive(server))
 536                         return -ECONNABORTED;
 537                 if (cifs_rdma_enabled(server) && server->smbd_conn)
 538                         length = smbd_recv(server->smbd_conn, smb_msg);
 539                 else
 540                         length = sock_recvmsg(server->ssocket, smb_msg, 0);
 541
 542                 if (server->tcpStatus == CifsExiting)
 543                         return -ESHUTDOWN;
 544
 545                 if (server->tcpStatus == CifsNeedReconnect) {
 546                         cifs_reconnect(server);
 547                         return -ECONNABORTED;
 548                 }
 549
 550                 if (length == -ERESTARTSYS ||
 551                     length == -EAGAIN ||
 552                     length == -EINTR) {
 553                         /*
 554                          * Minimum sleep to prevent looping, allowing socket
 555                          * to clear and app threads to set tcpStatus
 556                          * CifsNeedReconnect if server hung.
 557                          */
 558                         usleep_range(1000, 2000);
 559                         length = 0;
 560                         continue;
 561                 }
 562
 563                 if (length <= 0) {
 564                         cifs_dbg(FYI, "Received no data or error: %d\n", length);
 565                         cifs_reconnect(server);
 566                         return -ECONNABORTED;
 567                 }
 568         }
 569         return total_read;
 570 }
 571
 572 int
 573 cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 574                       unsigned int to_read)
 575 {
 576         struct msghdr smb_msg;
 577         struct kvec iov = {.iov_base = buf, .iov_len = to_read};
 578         iov_iter_kvec(&smb_msg.msg_iter, READ, &iov, 1, to_read);
 579
 580         return cifs_readv_from_socket(server, &smb_msg);
 581 }
 582
 583 ssize_t
 584 cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
 585 {
 586         struct msghdr smb_msg;
 587
 588         /*
 589          *  iov_iter_discard already sets smb_msg.type and count and iov_offset
 590          *  and cifs_readv_from_socket sets msg_control and msg_controllen
 591          *  so little to initialize in struct msghdr
 592          */
 593         smb_msg.msg_name = NULL;
 594         smb_msg.msg_namelen = 0;
 595         iov_iter_discard(&smb_msg.msg_iter, READ, to_read);
 596
 597         return cifs_readv_from_socket(server, &smb_msg);
 598 }
 599
 600 int
 601 cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 602         unsigned int page_offset, unsigned int to_read)
 603 {
 604         struct msghdr smb_msg;
 605         struct bio_vec bv = {
 606                 .bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
 607         iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read);
 608         return cifs_readv_from_socket(server, &smb_msg);
 609 }
 610
 611 static bool
 612 is_smb_response(struct TCP_Server_Info *server, unsigned char type)
 613 {
 614         /*
 615          * The first byte big endian of the length field,
 616          * is actually not part of the length but the type
 617          * with the most common, zero, as regular data.
 618          */
 619         switch (type) {
 620         case RFC1002_SESSION_MESSAGE:
 621                 /* Regular SMB response */
 622                 return true;
 623         case RFC1002_SESSION_KEEP_ALIVE:
 624                 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
 625                 break;
 626         case RFC1002_POSITIVE_SESSION_RESPONSE:
 627                 cifs_dbg(FYI, "RFC 1002 positive session response\n");
 628                 break;
 629         case RFC1002_NEGATIVE_SESSION_RESPONSE:
 630                 /*
 631                  * We get this from Windows 98 instead of an error on
 632                  * SMB negprot response.
 633                  */
 634                 cifs_dbg(FYI, "RFC 1002 negative session response\n");
 635                 /* give server a second to clean up */
 636                 msleep(1000);
 637                 /*
 638                  * Always try 445 first on reconnect since we get NACK
 639                  * on some if we ever connected to port 139 (the NACK
 640                  * is since we do not begin with RFC1001 session
 641                  * initialize frame).
 642                  */
 643                 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
 644                 cifs_reconnect(server);
 645                 break;
 646         default:
 647                 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
 648                 cifs_reconnect(server);
 649         }
 650
 651         return false;
 652 }
 653
 654 void
 655 dequeue_mid(struct mid_q_entry *mid, bool malformed)
 656 {
 657 #ifdef CONFIG_CIFS_STATS2
 658         mid->when_received = jiffies;
 659 #endif
 660         spin_lock(&GlobalMid_Lock);
 661         if (!malformed)
 662                 mid->mid_state = MID_RESPONSE_RECEIVED;
 663         else
 664                 mid->mid_state = MID_RESPONSE_MALFORMED;
 665         /*
 666          * Trying to handle/dequeue a mid after the send_recv()
 667          * function has finished processing it is a bug.
 668          */
 669         if (mid->mid_flags & MID_DELETED)
 670                 pr_warn_once("trying to dequeue a deleted mid\n");
 671         else {
 672                 list_del_init(&mid->qhead);
 673                 mid->mid_flags |= MID_DELETED;
 674         }
 675         spin_unlock(&GlobalMid_Lock);
 676 }
 677
 678 static unsigned int
 679 smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 680 {
 681         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
 682
 683         /*
 684          * SMB1 does not use credits.
 685          */
 686         if (server->vals->header_preamble_size)
 687                 return 0;
 688
 689         return le16_to_cpu(shdr->CreditRequest);
 690 }
 691
 692 static void
 693 handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 694            char *buf, int malformed)
 695 {
 696         if (server->ops->check_trans2 &&
 697             server->ops->check_trans2(mid, server, buf, malformed))
 698                 return;
 699         mid->credits_received = smb2_get_credits_from_hdr(buf, server);
 700         mid->resp_buf = buf;
 701         mid->large_buf = server->large_buf;
 702         /* Was previous buf put in mpx struct for multi-rsp? */
 703         if (!mid->multiRsp) {
 704                 /* smb buffer will be freed by user thread */
 705                 if (server->large_buf)
 706                         server->bigbuf = NULL;
 707                 else
 708                         server->smallbuf = NULL;
 709         }
 710         dequeue_mid(mid, malformed);
 711 }
 712
 713 static void clean_demultiplex_info(struct TCP_Server_Info *server)
 714 {
 715         int length;
 716
 717         /* take it off the list, if it's not already */
 718         spin_lock(&cifs_tcp_ses_lock);
 719         list_del_init(&server->tcp_ses_list);
 720         spin_unlock(&cifs_tcp_ses_lock);
 721
 722         cancel_delayed_work_sync(&server->echo);
 723         cancel_delayed_work_sync(&server->resolve);
 724
 725         spin_lock(&GlobalMid_Lock);
 726         server->tcpStatus = CifsExiting;
 727         spin_unlock(&GlobalMid_Lock);
 728         wake_up_all(&server->response_q);
 729
 730         /* check if we have blocked requests that need to free */
 731         spin_lock(&server->req_lock);
 732         if (server->credits <= 0)
 733                 server->credits = 1;
 734         spin_unlock(&server->req_lock);
 735         /*
 736          * Although there should not be any requests blocked on this queue it
 737          * can not hurt to be paranoid and try to wake up requests that may
 738          * haven been blocked when more than 50 at time were on the wire to the
 739          * same server - they now will see the session is in exit state and get
 740          * out of SendReceive.
 741          */
 742         wake_up_all(&server->request_q);
 743         /* give those requests time to exit */
 744         msleep(125);
 745         if (cifs_rdma_enabled(server))
 746                 smbd_destroy(server);
 747         if (server->ssocket) {
 748                 sock_release(server->ssocket);
 749                 server->ssocket = NULL;
 750         }
 751
 752         if (!list_empty(&server->pending_mid_q)) {
 753                 struct list_head dispose_list;
 754                 struct mid_q_entry *mid_entry;
 755                 struct list_head *tmp, *tmp2;
 756
 757                 INIT_LIST_HEAD(&dispose_list);
 758                 spin_lock(&GlobalMid_Lock);
 759                 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 760                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 761                         cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
 762                         kref_get(&mid_entry->refcount);
 763                         mid_entry->mid_state = MID_SHUTDOWN;
 764                         list_move(&mid_entry->qhead, &dispose_list);
 765                         mid_entry->mid_flags |= MID_DELETED;
 766                 }
 767                 spin_unlock(&GlobalMid_Lock);
 768
 769                 /* now walk dispose list and issue callbacks */
 770                 list_for_each_safe(tmp, tmp2, &dispose_list) {
 771                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 772                         cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
 773                         list_del_init(&mid_entry->qhead);
 774                         mid_entry->callback(mid_entry);
 775                         cifs_mid_q_entry_release(mid_entry);
 776                 }
 777                 /* 1/8th of sec is more than enough time for them to exit */
 778                 msleep(125);
 779         }
 780
 781         if (!list_empty(&server->pending_mid_q)) {
 782                 /*
 783                  * mpx threads have not exited yet give them at least the smb
 784                  * send timeout time for long ops.
 785                  *
 786                  * Due to delays on oplock break requests, we need to wait at
 787                  * least 45 seconds before giving up on a request getting a
 788                  * response and going ahead and killing cifsd.
 789                  */
 790                 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
 791                 msleep(46000);
 792                 /*
 793                  * If threads still have not exited they are probably never
 794                  * coming home not much else we can do but free the memory.
 795                  */
 796         }
 797
 798         kfree(server->hostname);
 799         kfree(server);
 800
 801         length = atomic_dec_return(&tcpSesAllocCount);
 802         if (length > 0)
 803                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
 804 }
 805
 806 static int
 807 standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 808 {
 809         int length;
 810         char *buf = server->smallbuf;
 811         unsigned int pdu_length = server->pdu_size;
 812
 813         /* make sure this will fit in a large buffer */
 814         if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
 815                 server->vals->header_preamble_size) {
 816                 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
 817                 cifs_reconnect(server);
 818                 return -ECONNABORTED;
 819         }
 820
 821         /* switch to large buffer if too big for a small one */
 822         if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
 823                 server->large_buf = true;
 824                 memcpy(server->bigbuf, buf, server->total_read);
 825                 buf = server->bigbuf;
 826         }
 827
 828         /* now read the rest */
 829         length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
 830                                        pdu_length - HEADER_SIZE(server) + 1
 831                                        + server->vals->header_preamble_size);
 832
 833         if (length < 0)
 834                 return length;
 835         server->total_read += length;
 836
 837         dump_smb(buf, server->total_read);
 838
 839         return cifs_handle_standard(server, mid);
 840 }
 841
 842 int
 843 cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
 844 {
 845         char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
 846         int length;
 847
 848         /*
 849          * We know that we received enough to get to the MID as we
 850          * checked the pdu_length earlier. Now check to see
 851          * if the rest of the header is OK. We borrow the length
 852          * var for the rest of the loop to avoid a new stack var.
 853          *
 854          * 48 bytes is enough to display the header and a little bit
 855          * into the payload for debugging purposes.
 856          */
 857         length = server->ops->check_message(buf, server->total_read, server);
 858         if (length != 0)
 859                 cifs_dump_mem("Bad SMB: ", buf,
 860                         min_t(unsigned int, server->total_read, 48));
 861
 862         if (server->ops->is_session_expired &&
 863             server->ops->is_session_expired(buf)) {
 864                 cifs_reconnect(server);
 865                 return -1;
 866         }
 867
 868         if (server->ops->is_status_pending &&
 869             server->ops->is_status_pending(buf, server))
 870                 return -1;
 871
 872         if (!mid)
 873                 return length;
 874
 875         handle_mid(mid, server, buf, length);
 876         return 0;
 877 }
 878
 879 static void
 880 smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 881 {
 882         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
 883         int scredits, in_flight;
 884
 885         /*
 886          * SMB1 does not use credits.
 887          */
 888         if (server->vals->header_preamble_size)
 889                 return;
 890
 891         if (shdr->CreditRequest) {
 892                 spin_lock(&server->req_lock);
 893                 server->credits += le16_to_cpu(shdr->CreditRequest);
 894                 scredits = server->credits;
 895                 in_flight = server->in_flight;
 896                 spin_unlock(&server->req_lock);
 897                 wake_up(&server->request_q);
 898
 899                 trace_smb3_add_credits(server->CurrentMid,
 900                                 server->conn_id, server->hostname, scredits,
 901                                 le16_to_cpu(shdr->CreditRequest), in_flight);
 902                 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
 903                                 __func__, le16_to_cpu(shdr->CreditRequest),
 904                                 scredits);
 905         }
 906 }
 907
 908
 909 static int
 910 cifs_demultiplex_thread(void *p)
 911 {
 912         int i, num_mids, length;
 913         struct TCP_Server_Info *server = p;
 914         unsigned int pdu_length;
 915         unsigned int next_offset;
 916         char *buf = NULL;
 917         struct task_struct *task_to_wake = NULL;
 918         struct mid_q_entry *mids[MAX_COMPOUND];
 919         char *bufs[MAX_COMPOUND];
 920         unsigned int noreclaim_flag, num_io_timeout = 0;
 921
 922         noreclaim_flag = memalloc_noreclaim_save();
 923         cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
 924
 925         length = atomic_inc_return(&tcpSesAllocCount);
 926         if (length > 1)
 927                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
 928
 929         set_freezable();
 930         allow_kernel_signal(SIGKILL);
 931         while (server->tcpStatus != CifsExiting) {
 932                 if (try_to_freeze())
 933                         continue;
 934
 935                 if (!allocate_buffers(server))
 936                         continue;
 937
 938                 server->large_buf = false;
 939                 buf = server->smallbuf;
 940                 pdu_length = 4; /* enough to get RFC1001 header */
 941
 942                 length = cifs_read_from_socket(server, buf, pdu_length);
 943                 if (length < 0)
 944                         continue;
 945
 946                 if (server->vals->header_preamble_size == 0)
 947                         server->total_read = 0;
 948                 else
 949                         server->total_read = length;
 950
 951                 /*
 952                  * The right amount was read from socket - 4 bytes,
 953                  * so we can now interpret the length field.
 954                  */
 955                 pdu_length = get_rfc1002_length(buf);
 956
 957                 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
 958                 if (!is_smb_response(server, buf[0]))
 959                         continue;
 960 next_pdu:
 961                 server->pdu_size = pdu_length;
 962
 963                 /* make sure we have enough to get to the MID */
 964                 if (server->pdu_size < HEADER_SIZE(server) - 1 -
 965                     server->vals->header_preamble_size) {
 966                         cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
 967                                  server->pdu_size);
 968                         cifs_reconnect(server);
 969                         continue;
 970                 }
 971
 972                 /* read down to the MID */
 973                 length = cifs_read_from_socket(server,
 974                              buf + server->vals->header_preamble_size,
 975                              HEADER_SIZE(server) - 1
 976                              - server->vals->header_preamble_size);
 977                 if (length < 0)
 978                         continue;
 979                 server->total_read += length;
 980
 981                 if (server->ops->next_header) {
 982                         next_offset = server->ops->next_header(buf);
 983                         if (next_offset)
 984                                 server->pdu_size = next_offset;
 985                 }
 986
 987                 memset(mids, 0, sizeof(mids));
 988                 memset(bufs, 0, sizeof(bufs));
 989                 num_mids = 0;
 990
 991                 if (server->ops->is_transform_hdr &&
 992                     server->ops->receive_transform &&
 993                     server->ops->is_transform_hdr(buf)) {
 994                         length = server->ops->receive_transform(server,
 995                                                                 mids,
 996                                                                 bufs,
 997                                                                 &num_mids);
 998                 } else {
 999                         mids[0] = server->ops->find_mid(server, buf);
1000                         bufs[0] = buf;
1001                         num_mids = 1;
1002
1003                         if (!mids[0] || !mids[0]->receive)
1004                                 length = standard_receive3(server, mids[0]);
1005                         else
1006                                 length = mids[0]->receive(server, mids[0]);
1007                 }
1008
1009                 if (length < 0) {
1010                         for (i = 0; i < num_mids; i++)
1011                                 if (mids[i])
1012                                         cifs_mid_q_entry_release(mids[i]);
1013                         continue;
1014                 }
1015
1016                 if (server->ops->is_status_io_timeout &&
1017                     server->ops->is_status_io_timeout(buf)) {
1018                         num_io_timeout++;
1019                         if (num_io_timeout > NUM_STATUS_IO_TIMEOUT) {
1020                                 cifs_reconnect(server);
1021                                 num_io_timeout = 0;
1022                                 continue;
1023                         }
1024                 }
1025
1026                 server->lstrp = jiffies;
1027
1028                 for (i = 0; i < num_mids; i++) {
1029                         if (mids[i] != NULL) {
1030                                 mids[i]->resp_buf_size = server->pdu_size;
1031
1032                                 if (bufs[i] && server->ops->is_network_name_deleted)
1033                                         server->ops->is_network_name_deleted(bufs[i],
1034                                                                         server);
1035
1036                                 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1037                                         mids[i]->callback(mids[i]);
1038
1039                                 cifs_mid_q_entry_release(mids[i]);
1040                         } else if (server->ops->is_oplock_break &&
1041                                    server->ops->is_oplock_break(bufs[i],
1042                                                                 server)) {
1043                                 smb2_add_credits_from_hdr(bufs[i], server);
1044                                 cifs_dbg(FYI, "Received oplock break\n");
1045                         } else {
1046                                 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1047                                                 atomic_read(&midCount));
1048                                 cifs_dump_mem("Received Data is: ", bufs[i],
1049                                               HEADER_SIZE(server));
1050                                 smb2_add_credits_from_hdr(bufs[i], server);
1051 #ifdef CONFIG_CIFS_DEBUG2
1052                                 if (server->ops->dump_detail)
1053                                         server->ops->dump_detail(bufs[i],
1054                                                                  server);
1055                                 cifs_dump_mids(server);
1056 #endif /* CIFS_DEBUG2 */
1057                         }
1058                 }
1059
1060                 if (pdu_length > server->pdu_size) {
1061                         if (!allocate_buffers(server))
1062                                 continue;
1063                         pdu_length -= server->pdu_size;
1064                         server->total_read = 0;
1065                         server->large_buf = false;
1066                         buf = server->smallbuf;
1067                         goto next_pdu;
1068                 }
1069         } /* end while !EXITING */
1070
1071         /* buffer usually freed in free_mid - need to free it here on exit */
1072         cifs_buf_release(server->bigbuf);
1073         if (server->smallbuf) /* no sense logging a debug message if NULL */
1074                 cifs_small_buf_release(server->smallbuf);
1075
1076         task_to_wake = xchg(&server->tsk, NULL);
1077         clean_demultiplex_info(server);
1078
1079         /* if server->tsk was NULL then wait for a signal before exiting */
1080         if (!task_to_wake) {
1081                 set_current_state(TASK_INTERRUPTIBLE);
1082                 while (!signal_pending(current)) {
1083                         schedule();
1084                         set_current_state(TASK_INTERRUPTIBLE);
1085                 }
1086                 set_current_state(TASK_RUNNING);
1087         }
1088
1089         memalloc_noreclaim_restore(noreclaim_flag);
1090         module_put_and_exit(0);
1091 }
1092
1093 /**
1094  * Returns true if srcaddr isn't specified and rhs isn't specified, or
1095  * if srcaddr is specified and matches the IP address of the rhs argument
1096  */
1097 bool
1098 cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1099 {
1100         switch (srcaddr->sa_family) {
1101         case AF_UNSPEC:
1102                 return (rhs->sa_family == AF_UNSPEC);
1103         case AF_INET: {
1104                 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1105                 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1106                 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1107         }
1108         case AF_INET6: {
1109                 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1110                 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1111                 return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
1112         }
1113         default:
1114                 WARN_ON(1);
1115                 return false; /* don't expect to be here */
1116         }
1117 }
1118
1119 /*
1120  * If no port is specified in addr structure, we try to match with 445 port
1121  * and if it fails - with 139 ports. It should be called only if address
1122  * families of server and addr are equal.
1123  */
1124 static bool
1125 match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1126 {
1127         __be16 port, *sport;
1128
1129         /* SMBDirect manages its own ports, don't match it here */
1130         if (server->rdma)
1131                 return true;
1132
1133         switch (addr->sa_family) {
1134         case AF_INET:
1135                 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1136                 port = ((struct sockaddr_in *) addr)->sin_port;
1137                 break;
1138         case AF_INET6:
1139                 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1140                 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1141                 break;
1142         default:
1143                 WARN_ON(1);
1144                 return false;
1145         }
1146
1147         if (!port) {
1148                 port = htons(CIFS_PORT);
1149                 if (port == *sport)
1150                         return true;
1151
1152                 port = htons(RFC1001_PORT);
1153         }
1154
1155         return port == *sport;
1156 }
1157
1158 static bool
1159 match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
1160               struct sockaddr *srcaddr)
1161 {
1162         switch (addr->sa_family) {
1163         case AF_INET: {
1164                 struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
1165                 struct sockaddr_in *srv_addr4 =
1166                                         (struct sockaddr_in *)&server->dstaddr;
1167
1168                 if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
1169                         return false;
1170                 break;
1171         }
1172         case AF_INET6: {
1173                 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
1174                 struct sockaddr_in6 *srv_addr6 =
1175                                         (struct sockaddr_in6 *)&server->dstaddr;
1176
1177                 if (!ipv6_addr_equal(&addr6->sin6_addr,
1178                                      &srv_addr6->sin6_addr))
1179                         return false;
1180                 if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
1181                         return false;
1182                 break;
1183         }
1184         default:
1185                 WARN_ON(1);
1186                 return false; /* don't expect to be here */
1187         }
1188
1189         if (!cifs_match_ipaddr(srcaddr, (struct sockaddr *)&server->srcaddr))
1190                 return false;
1191
1192         return true;
1193 }
1194
1195 static bool
1196 match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1197 {
1198         /*
1199          * The select_sectype function should either return the ctx->sectype
1200          * that was specified, or "Unspecified" if that sectype was not
1201          * compatible with the given NEGOTIATE request.
1202          */
1203         if (server->ops->select_sectype(server, ctx->sectype)
1204              == Unspecified)
1205                 return false;
1206
1207         /*
1208          * Now check if signing mode is acceptable. No need to check
1209          * global_secflags at this point since if MUST_SIGN is set then
1210          * the server->sign had better be too.
1211          */
1212         if (ctx->sign && !server->sign)
1213                 return false;
1214
1215         return true;
1216 }
1217
1218 static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1219 {
1220         struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1221
1222         if (ctx->nosharesock)
1223                 return 0;
1224
1225         /* If multidialect negotiation see if existing sessions match one */
1226         if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1227                 if (server->vals->protocol_id < SMB30_PROT_ID)
1228                         return 0;
1229         } else if (strcmp(ctx->vals->version_string,
1230                    SMBDEFAULT_VERSION_STRING) == 0) {
1231                 if (server->vals->protocol_id < SMB21_PROT_ID)
1232                         return 0;
1233         } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1234                 return 0;
1235
1236         if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1237                 return 0;
1238
1239         if (!match_address(server, addr,
1240                            (struct sockaddr *)&ctx->srcaddr))
1241                 return 0;
1242
1243         if (!match_port(server, addr))
1244                 return 0;
1245
1246         if (!match_security(server, ctx))
1247                 return 0;
1248
1249         if (server->echo_interval != ctx->echo_interval * HZ)
1250                 return 0;
1251
1252         if (server->rdma != ctx->rdma)
1253                 return 0;
1254
1255         if (server->ignore_signature != ctx->ignore_signature)
1256                 return 0;
1257
1258         if (server->min_offload != ctx->min_offload)
1259                 return 0;
1260
1261         return 1;
1262 }
1263
1264 struct TCP_Server_Info *
1265 cifs_find_tcp_session(struct smb3_fs_context *ctx)
1266 {
1267         struct TCP_Server_Info *server;
1268
1269         spin_lock(&cifs_tcp_ses_lock);
1270         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1271 #ifdef CONFIG_CIFS_DFS_UPCALL
1272                 /*
1273                  * DFS failover implementation in cifs_reconnect() requires unique tcp sessions for
1274                  * DFS connections to do failover properly, so avoid sharing them with regular
1275                  * shares or even links that may connect to same server but having completely
1276                  * different failover targets.
1277                  */
1278                 if (server->is_dfs_conn)
1279                         continue;
1280 #endif
1281                 /*
1282                  * Skip ses channels since they're only handled in lower layers
1283                  * (e.g. cifs_send_recv).
1284                  */
1285                 if (server->is_channel || !match_server(server, ctx))
1286                         continue;
1287
1288                 ++server->srv_count;
1289                 spin_unlock(&cifs_tcp_ses_lock);
1290                 cifs_dbg(FYI, "Existing tcp session with server found\n");
1291                 return server;
1292         }
1293         spin_unlock(&cifs_tcp_ses_lock);
1294         return NULL;
1295 }
1296
1297 void
1298 cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1299 {
1300         struct task_struct *task;
1301
1302         spin_lock(&cifs_tcp_ses_lock);
1303         if (--server->srv_count > 0) {
1304                 spin_unlock(&cifs_tcp_ses_lock);
1305                 return;
1306         }
1307
1308         /* srv_count can never go negative */
1309         WARN_ON(server->srv_count < 0);
1310
1311         put_net(cifs_net_ns(server));
1312
1313         list_del_init(&server->tcp_ses_list);
1314         spin_unlock(&cifs_tcp_ses_lock);
1315
1316         cancel_delayed_work_sync(&server->echo);
1317         cancel_delayed_work_sync(&server->resolve);
1318
1319         if (from_reconnect)
1320                 /*
1321                  * Avoid deadlock here: reconnect work calls
1322                  * cifs_put_tcp_session() at its end. Need to be sure
1323                  * that reconnect work does nothing with server pointer after
1324                  * that step.
1325                  */
1326                 cancel_delayed_work(&server->reconnect);
1327         else
1328                 cancel_delayed_work_sync(&server->reconnect);
1329
1330         spin_lock(&GlobalMid_Lock);
1331         server->tcpStatus = CifsExiting;
1332         spin_unlock(&GlobalMid_Lock);
1333
1334         cifs_crypto_secmech_release(server);
1335         cifs_fscache_release_client_cookie(server);
1336
1337         kfree(server->session_key.response);
1338         server->session_key.response = NULL;
1339         server->session_key.len = 0;
1340
1341         task = xchg(&server->tsk, NULL);
1342         if (task)
1343                 send_sig(SIGKILL, task, 1);
1344 }
1345
1346 struct TCP_Server_Info *
1347 cifs_get_tcp_session(struct smb3_fs_context *ctx)
1348 {
1349         struct TCP_Server_Info *tcp_ses = NULL;
1350         int rc;
1351
1352         cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1353
1354         /* see if we already have a matching tcp_ses */
1355         tcp_ses = cifs_find_tcp_session(ctx);
1356         if (tcp_ses)
1357                 return tcp_ses;
1358
1359         tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1360         if (!tcp_ses) {
1361                 rc = -ENOMEM;
1362                 goto out_err;
1363         }
1364
1365         tcp_ses->ops = ctx->ops;
1366         tcp_ses->vals = ctx->vals;
1367         cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1368         tcp_ses->hostname = extract_hostname(ctx->UNC);
1369         if (IS_ERR(tcp_ses->hostname)) {
1370                 rc = PTR_ERR(tcp_ses->hostname);
1371                 goto out_err_crypto_release;
1372         }
1373
1374         tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1375         tcp_ses->noblockcnt = ctx->rootfs;
1376         tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1377         tcp_ses->noautotune = ctx->noautotune;
1378         tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1379         tcp_ses->rdma = ctx->rdma;
1380         tcp_ses->in_flight = 0;
1381         tcp_ses->max_in_flight = 0;
1382         tcp_ses->credits = 1;
1383         init_waitqueue_head(&tcp_ses->response_q);
1384         init_waitqueue_head(&tcp_ses->request_q);
1385         INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1386         mutex_init(&tcp_ses->srv_mutex);
1387         memcpy(tcp_ses->workstation_RFC1001_name,
1388                 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1389         memcpy(tcp_ses->server_RFC1001_name,
1390                 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1391         tcp_ses->session_estab = false;
1392         tcp_ses->sequence_number = 0;
1393         tcp_ses->reconnect_instance = 1;
1394         tcp_ses->lstrp = jiffies;
1395         tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1396         spin_lock_init(&tcp_ses->req_lock);
1397         INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1398         INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1399         INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1400         INIT_DELAYED_WORK(&tcp_ses->resolve, cifs_resolve_server);
1401         INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1402         mutex_init(&tcp_ses->reconnect_mutex);
1403         memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1404                sizeof(tcp_ses->srcaddr));
1405         memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1406                 sizeof(tcp_ses->dstaddr));
1407         if (ctx->use_client_guid)
1408                 memcpy(tcp_ses->client_guid, ctx->client_guid,
1409                        SMB2_CLIENT_GUID_SIZE);
1410         else
1411                 generate_random_uuid(tcp_ses->client_guid);
1412         /*
1413          * at this point we are the only ones with the pointer
1414          * to the struct since the kernel thread not created yet
1415          * no need to spinlock this init of tcpStatus or srv_count
1416          */
1417         tcp_ses->tcpStatus = CifsNew;
1418         ++tcp_ses->srv_count;
1419
1420         if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1421                 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1422                 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1423         else
1424                 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1425         if (tcp_ses->rdma) {
1426 #ifndef CONFIG_CIFS_SMB_DIRECT
1427                 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1428                 rc = -ENOENT;
1429                 goto out_err_crypto_release;
1430 #endif
1431                 tcp_ses->smbd_conn = smbd_get_connection(
1432                         tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1433                 if (tcp_ses->smbd_conn) {
1434                         cifs_dbg(VFS, "RDMA transport established\n");
1435                         rc = 0;
1436                         goto smbd_connected;
1437                 } else {
1438                         rc = -ENOENT;
1439                         goto out_err_crypto_release;
1440                 }
1441         }
1442         rc = ip_connect(tcp_ses);
1443         if (rc < 0) {
1444                 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1445                 goto out_err_crypto_release;
1446         }
1447 smbd_connected:
1448         /*
1449          * since we're in a cifs function already, we know that
1450          * this will succeed. No need for try_module_get().
1451          */
1452         __module_get(THIS_MODULE);
1453         tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1454                                   tcp_ses, "cifsd");
1455         if (IS_ERR(tcp_ses->tsk)) {
1456                 rc = PTR_ERR(tcp_ses->tsk);
1457                 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1458                 module_put(THIS_MODULE);
1459                 goto out_err_crypto_release;
1460         }
1461         tcp_ses->min_offload = ctx->min_offload;
1462         /*
1463          * at this point we are the only ones with the pointer
1464          * to the struct since the kernel thread not created yet
1465          * no need to spinlock this update of tcpStatus
1466          */
1467         tcp_ses->tcpStatus = CifsNeedNegotiate;
1468
1469         if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1470                 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1471         else
1472                 tcp_ses->max_credits = ctx->max_credits;
1473
1474         tcp_ses->nr_targets = 1;
1475         tcp_ses->ignore_signature = ctx->ignore_signature;
1476         /* thread spawned, put it on the list */
1477         spin_lock(&cifs_tcp_ses_lock);
1478         list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1479         spin_unlock(&cifs_tcp_ses_lock);
1480
1481         cifs_fscache_get_client_cookie(tcp_ses);
1482
1483         /* queue echo request delayed work */
1484         queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1485
1486         /* queue dns resolution delayed work */
1487         cifs_dbg(FYI, "%s: next dns resolution scheduled for %d seconds in the future\n",
1488                  __func__, SMB_DNS_RESOLVE_INTERVAL_DEFAULT);
1489
1490         queue_delayed_work(cifsiod_wq, &tcp_ses->resolve, (SMB_DNS_RESOLVE_INTERVAL_DEFAULT * HZ));
1491
1492         return tcp_ses;
1493
1494 out_err_crypto_release:
1495         cifs_crypto_secmech_release(tcp_ses);
1496
1497         put_net(cifs_net_ns(tcp_ses));
1498
1499 out_err:
1500         if (tcp_ses) {
1501                 if (!IS_ERR(tcp_ses->hostname))
1502                         kfree(tcp_ses->hostname);
1503                 if (tcp_ses->ssocket)
1504                         sock_release(tcp_ses->ssocket);
1505                 kfree(tcp_ses);
1506         }
1507         return ERR_PTR(rc);
1508 }
1509
1510 static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1511 {
1512         if (ctx->sectype != Unspecified &&
1513             ctx->sectype != ses->sectype)
1514                 return 0;
1515
1516         /*
1517          * If an existing session is limited to less channels than
1518          * requested, it should not be reused
1519          */
1520         if (ses->chan_max < ctx->max_channels)
1521                 return 0;
1522
1523         switch (ses->sectype) {
1524         case Kerberos:
1525                 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1526                         return 0;
1527                 break;
1528         default:
1529                 /* NULL username means anonymous session */
1530                 if (ses->user_name == NULL) {
1531                         if (!ctx->nullauth)
1532                                 return 0;
1533                         break;
1534                 }
1535
1536                 /* anything else takes username/password */
1537                 if (strncmp(ses->user_name,
1538                             ctx->username ? ctx->username : "",
1539                             CIFS_MAX_USERNAME_LEN))
1540                         return 0;
1541                 if ((ctx->username && strlen(ctx->username) != 0) &&
1542                     ses->password != NULL &&
1543                     strncmp(ses->password,
1544                             ctx->password ? ctx->password : "",
1545                             CIFS_MAX_PASSWORD_LEN))
1546                         return 0;
1547         }
1548         return 1;
1549 }
1550
1551 /**
1552  * cifs_setup_ipc - helper to setup the IPC tcon for the session
1553  *
1554  * A new IPC connection is made and stored in the session
1555  * tcon_ipc. The IPC tcon has the same lifetime as the session.
1556  */
1557 static int
1558 cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1559 {
1560         int rc = 0, xid;
1561         struct cifs_tcon *tcon;
1562         char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1563         bool seal = false;
1564         struct TCP_Server_Info *server = ses->server;
1565
1566         /*
1567          * If the mount request that resulted in the creation of the
1568          * session requires encryption, force IPC to be encrypted too.
1569          */
1570         if (ctx->seal) {
1571                 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1572                         seal = true;
1573                 else {
1574                         cifs_server_dbg(VFS,
1575                                  "IPC: server doesn't support encryption\n");
1576                         return -EOPNOTSUPP;
1577                 }
1578         }
1579
1580         tcon = tconInfoAlloc();
1581         if (tcon == NULL)
1582                 return -ENOMEM;
1583
1584         scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1585
1586         xid = get_xid();
1587         tcon->ses = ses;
1588         tcon->ipc = true;
1589         tcon->seal = seal;
1590         rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1591         free_xid(xid);
1592
1593         if (rc) {
1594                 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1595                 tconInfoFree(tcon);
1596                 goto out;
1597         }
1598
1599         cifs_dbg(FYI, "IPC tcon rc = %d ipc tid = %d\n", rc, tcon->tid);
1600
1601         ses->tcon_ipc = tcon;
1602 out:
1603         return rc;
1604 }
1605
1606 /**
1607  * cifs_free_ipc - helper to release the session IPC tcon
1608  *
1609  * Needs to be called everytime a session is destroyed.
1610  *
1611  * On session close, the IPC is closed and the server must release all tcons of the session.
1612  * No need to send a tree disconnect here.
1613  *
1614  * Besides, it will make the server to not close durable and resilient files on session close, as
1615  * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1616  */
1617 static int
1618 cifs_free_ipc(struct cifs_ses *ses)
1619 {
1620         struct cifs_tcon *tcon = ses->tcon_ipc;
1621
1622         if (tcon == NULL)
1623                 return 0;
1624
1625         tconInfoFree(tcon);
1626         ses->tcon_ipc = NULL;
1627         return 0;
1628 }
1629
1630 static struct cifs_ses *
1631 cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1632 {
1633         struct cifs_ses *ses;
1634
1635         spin_lock(&cifs_tcp_ses_lock);
1636         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1637                 if (ses->status == CifsExiting)
1638                         continue;
1639                 if (!match_session(ses, ctx))
1640                         continue;
1641                 ++ses->ses_count;
1642                 spin_unlock(&cifs_tcp_ses_lock);
1643                 return ses;
1644         }
1645         spin_unlock(&cifs_tcp_ses_lock);
1646         return NULL;
1647 }
1648
1649 void cifs_put_smb_ses(struct cifs_ses *ses)
1650 {
1651         unsigned int rc, xid;
1652         struct TCP_Server_Info *server = ses->server;
1653         cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
1654
1655         spin_lock(&cifs_tcp_ses_lock);
1656         if (ses->status == CifsExiting) {
1657                 spin_unlock(&cifs_tcp_ses_lock);
1658                 return;
1659         }
1660
1661         cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
1662         cifs_dbg(FYI, "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->treeName : "NONE");
1663
1664         if (--ses->ses_count > 0) {
1665                 spin_unlock(&cifs_tcp_ses_lock);
1666                 return;
1667         }
1668         spin_unlock(&cifs_tcp_ses_lock);
1669
1670         /* ses_count can never go negative */
1671         WARN_ON(ses->ses_count < 0);
1672
1673         spin_lock(&GlobalMid_Lock);
1674         if (ses->status == CifsGood)
1675                 ses->status = CifsExiting;
1676         spin_unlock(&GlobalMid_Lock);
1677
1678         cifs_free_ipc(ses);
1679
1680         if (ses->status == CifsExiting && server->ops->logoff) {
1681                 xid = get_xid();
1682                 rc = server->ops->logoff(xid, ses);
1683                 if (rc)
1684                         cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
1685                                 __func__, rc);
1686                 _free_xid(xid);
1687         }
1688
1689         spin_lock(&cifs_tcp_ses_lock);
1690         list_del_init(&ses->smb_ses_list);
1691         spin_unlock(&cifs_tcp_ses_lock);
1692
1693         /* close any extra channels */
1694         if (ses->chan_count > 1) {
1695                 int i;
1696
1697                 for (i = 1; i < ses->chan_count; i++)
1698                         cifs_put_tcp_session(ses->chans[i].server, 0);
1699         }
1700
1701         sesInfoFree(ses);
1702         cifs_put_tcp_session(server, 0);
1703 }
1704
1705 #ifdef CONFIG_KEYS
1706
1707 /* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
1708 #define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
1709
1710 /* Populate username and pw fields from keyring if possible */
1711 static int
1712 cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
1713 {
1714         int rc = 0;
1715         int is_domain = 0;
1716         const char *delim, *payload;
1717         char *desc;
1718         ssize_t len;
1719         struct key *key;
1720         struct TCP_Server_Info *server = ses->server;
1721         struct sockaddr_in *sa;
1722         struct sockaddr_in6 *sa6;
1723         const struct user_key_payload *upayload;
1724
1725         desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
1726         if (!desc)
1727                 return -ENOMEM;
1728
1729         /* try to find an address key first */
1730         switch (server->dstaddr.ss_family) {
1731         case AF_INET:
1732                 sa = (struct sockaddr_in *)&server->dstaddr;
1733                 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
1734                 break;
1735         case AF_INET6:
1736                 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
1737                 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
1738                 break;
1739         default:
1740                 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
1741                          server->dstaddr.ss_family);
1742                 rc = -EINVAL;
1743                 goto out_err;
1744         }
1745
1746         cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
1747         key = request_key(&key_type_logon, desc, "");
1748         if (IS_ERR(key)) {
1749                 if (!ses->domainName) {
1750                         cifs_dbg(FYI, "domainName is NULL\n");
1751                         rc = PTR_ERR(key);
1752                         goto out_err;
1753                 }
1754
1755                 /* didn't work, try to find a domain key */
1756                 sprintf(desc, "cifs:d:%s", ses->domainName);
1757                 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
1758                 key = request_key(&key_type_logon, desc, "");
1759                 if (IS_ERR(key)) {
1760                         rc = PTR_ERR(key);
1761                         goto out_err;
1762                 }
1763                 is_domain = 1;
1764         }
1765
1766         down_read(&key->sem);
1767         upayload = user_key_payload_locked(key);
1768         if (IS_ERR_OR_NULL(upayload)) {
1769                 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
1770                 goto out_key_put;
1771         }
1772
1773         /* find first : in payload */
1774         payload = upayload->data;
1775         delim = strnchr(payload, upayload->datalen, ':');
1776         cifs_dbg(FYI, "payload=%s\n", payload);
1777         if (!delim) {
1778                 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
1779                          upayload->datalen);
1780                 rc = -EINVAL;
1781                 goto out_key_put;
1782         }
1783
1784         len = delim - payload;
1785         if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
1786                 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
1787                          len);
1788                 rc = -EINVAL;
1789                 goto out_key_put;
1790         }
1791
1792         ctx->username = kstrndup(payload, len, GFP_KERNEL);
1793         if (!ctx->username) {
1794                 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
1795                          len);
1796                 rc = -ENOMEM;
1797                 goto out_key_put;
1798         }
1799         cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
1800
1801         len = key->datalen - (len + 1);
1802         if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
1803                 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
1804                 rc = -EINVAL;
1805                 kfree(ctx->username);
1806                 ctx->username = NULL;
1807                 goto out_key_put;
1808         }
1809
1810         ++delim;
1811         ctx->password = kstrndup(delim, len, GFP_KERNEL);
1812         if (!ctx->password) {
1813                 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
1814                          len);
1815                 rc = -ENOMEM;
1816                 kfree(ctx->username);
1817                 ctx->username = NULL;
1818                 goto out_key_put;
1819         }
1820
1821         /*
1822          * If we have a domain key then we must set the domainName in the
1823          * for the request.
1824          */
1825         if (is_domain && ses->domainName) {
1826                 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
1827                 if (!ctx->domainname) {
1828                         cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
1829                                  len);
1830                         rc = -ENOMEM;
1831                         kfree(ctx->username);
1832                         ctx->username = NULL;
1833                         kfree_sensitive(ctx->password);
1834                         ctx->password = NULL;
1835                         goto out_key_put;
1836                 }
1837         }
1838
1839 out_key_put:
1840         up_read(&key->sem);
1841         key_put(key);
1842 out_err:
1843         kfree(desc);
1844         cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
1845         return rc;
1846 }
1847 #else /* ! CONFIG_KEYS */
1848 static inline int
1849 cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
1850                    struct cifs_ses *ses __attribute__((unused)))
1851 {
1852         return -ENOSYS;
1853 }
1854 #endif /* CONFIG_KEYS */
1855
1856 /**
1857  * cifs_get_smb_ses - get a session matching @ctx data from @server
1858  *
1859  * This function assumes it is being called from cifs_mount() where we
1860  * already got a server reference (server refcount +1). See
1861  * cifs_get_tcon() for refcount explanations.
1862  */
1863 struct cifs_ses *
1864 cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1865 {
1866         int rc = -ENOMEM;
1867         unsigned int xid;
1868         struct cifs_ses *ses;
1869         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
1870         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
1871
1872         xid = get_xid();
1873
1874         ses = cifs_find_smb_ses(server, ctx);
1875         if (ses) {
1876                 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
1877                          ses->status);
1878
1879                 mutex_lock(&ses->session_mutex);
1880                 rc = cifs_negotiate_protocol(xid, ses);
1881                 if (rc) {
1882                         mutex_unlock(&ses->session_mutex);
1883                         /* problem -- put our ses reference */
1884                         cifs_put_smb_ses(ses);
1885                         free_xid(xid);
1886                         return ERR_PTR(rc);
1887                 }
1888                 if (ses->need_reconnect) {
1889                         cifs_dbg(FYI, "Session needs reconnect\n");
1890                         rc = cifs_setup_session(xid, ses,
1891                                                 ctx->local_nls);
1892                         if (rc) {
1893                                 mutex_unlock(&ses->session_mutex);
1894                                 /* problem -- put our reference */
1895                                 cifs_put_smb_ses(ses);
1896                                 free_xid(xid);
1897                                 return ERR_PTR(rc);
1898                         }
1899                 }
1900                 mutex_unlock(&ses->session_mutex);
1901
1902                 /* existing SMB ses has a server reference already */
1903                 cifs_put_tcp_session(server, 0);
1904                 free_xid(xid);
1905                 return ses;
1906         }
1907
1908         cifs_dbg(FYI, "Existing smb sess not found\n");
1909         ses = sesInfoAlloc();
1910         if (ses == NULL)
1911                 goto get_ses_fail;
1912
1913         /* new SMB session uses our server ref */
1914         ses->server = server;
1915         if (server->dstaddr.ss_family == AF_INET6)
1916                 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
1917         else
1918                 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
1919
1920         if (ctx->username) {
1921                 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
1922                 if (!ses->user_name)
1923                         goto get_ses_fail;
1924         }
1925
1926         /* ctx->password freed at unmount */
1927         if (ctx->password) {
1928                 ses->password = kstrdup(ctx->password, GFP_KERNEL);
1929                 if (!ses->password)
1930                         goto get_ses_fail;
1931         }
1932         if (ctx->domainname) {
1933                 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
1934                 if (!ses->domainName)
1935                         goto get_ses_fail;
1936         }
1937         if (ctx->domainauto)
1938                 ses->domainAuto = ctx->domainauto;
1939         ses->cred_uid = ctx->cred_uid;
1940         ses->linux_uid = ctx->linux_uid;
1941
1942         ses->sectype = ctx->sectype;
1943         ses->sign = ctx->sign;
1944         mutex_lock(&ses->session_mutex);
1945
1946         /* add server as first channel */
1947         ses->chans[0].server = server;
1948         ses->chan_count = 1;
1949         ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
1950
1951         rc = cifs_negotiate_protocol(xid, ses);
1952         if (!rc)
1953                 rc = cifs_setup_session(xid, ses, ctx->local_nls);
1954
1955         /* each channel uses a different signing key */
1956         memcpy(ses->chans[0].signkey, ses->smb3signingkey,
1957                sizeof(ses->smb3signingkey));
1958
1959         mutex_unlock(&ses->session_mutex);
1960         if (rc)
1961                 goto get_ses_fail;
1962
1963         /* success, put it on the list and add it as first channel */
1964         spin_lock(&cifs_tcp_ses_lock);
1965         list_add(&ses->smb_ses_list, &server->smb_ses_list);
1966         spin_unlock(&cifs_tcp_ses_lock);
1967
1968         free_xid(xid);
1969
1970         cifs_setup_ipc(ses, ctx);
1971
1972         return ses;
1973
1974 get_ses_fail:
1975         sesInfoFree(ses);
1976         free_xid(xid);
1977         return ERR_PTR(rc);
1978 }
1979
1980 static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
1981 {
1982         if (tcon->tidStatus == CifsExiting)
1983                 return 0;
1984         if (strncmp(tcon->treeName, ctx->UNC, MAX_TREE_SIZE))
1985                 return 0;
1986         if (tcon->seal != ctx->seal)
1987                 return 0;
1988         if (tcon->snapshot_time != ctx->snapshot_time)
1989                 return 0;
1990         if (tcon->handle_timeout != ctx->handle_timeout)
1991                 return 0;
1992         if (tcon->no_lease != ctx->no_lease)
1993                 return 0;
1994         if (tcon->nodelete != ctx->nodelete)
1995                 return 0;
1996         return 1;
1997 }
1998
1999 static struct cifs_tcon *
2000 cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2001 {
2002         struct list_head *tmp;
2003         struct cifs_tcon *tcon;
2004
2005         spin_lock(&cifs_tcp_ses_lock);
2006         list_for_each(tmp, &ses->tcon_list) {
2007                 tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
2008
2009                 if (!match_tcon(tcon, ctx))
2010                         continue;
2011                 ++tcon->tc_count;
2012                 spin_unlock(&cifs_tcp_ses_lock);
2013                 return tcon;
2014         }
2015         spin_unlock(&cifs_tcp_ses_lock);
2016         return NULL;
2017 }
2018
2019 void
2020 cifs_put_tcon(struct cifs_tcon *tcon)
2021 {
2022         unsigned int xid;
2023         struct cifs_ses *ses;
2024
2025         /*
2026          * IPC tcon share the lifetime of their session and are
2027          * destroyed in the session put function
2028          */
2029         if (tcon == NULL || tcon->ipc)
2030                 return;
2031
2032         ses = tcon->ses;
2033         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2034         spin_lock(&cifs_tcp_ses_lock);
2035         if (--tcon->tc_count > 0) {
2036                 spin_unlock(&cifs_tcp_ses_lock);
2037                 return;
2038         }
2039
2040         /* tc_count can never go negative */
2041         WARN_ON(tcon->tc_count < 0);
2042
2043         if (tcon->use_witness) {
2044                 int rc;
2045
2046                 rc = cifs_swn_unregister(tcon);
2047                 if (rc < 0) {
2048                         cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2049                                         __func__, rc);
2050                 }
2051         }
2052
2053         list_del_init(&tcon->tcon_list);
2054         spin_unlock(&cifs_tcp_ses_lock);
2055
2056         xid = get_xid();
2057         if (ses->server->ops->tree_disconnect)
2058                 ses->server->ops->tree_disconnect(xid, tcon);
2059         _free_xid(xid);
2060
2061         cifs_fscache_release_super_cookie(tcon);
2062         tconInfoFree(tcon);
2063         cifs_put_smb_ses(ses);
2064 }
2065
2066 /**
2067  * cifs_get_tcon - get a tcon matching @ctx data from @ses
2068  *
2069  * - tcon refcount is the number of mount points using the tcon.
2070  * - ses refcount is the number of tcon using the session.
2071  *
2072  * 1. This function assumes it is being called from cifs_mount() where
2073  *    we already got a session reference (ses refcount +1).
2074  *
2075  * 2. Since we're in the context of adding a mount point, the end
2076  *    result should be either:
2077  *
2078  * a) a new tcon already allocated with refcount=1 (1 mount point) and
2079  *    its session refcount incremented (1 new tcon). This +1 was
2080  *    already done in (1).
2081  *
2082  * b) an existing tcon with refcount+1 (add a mount point to it) and
2083  *    identical ses refcount (no new tcon). Because of (1) we need to
2084  *    decrement the ses refcount.
2085  */
2086 static struct cifs_tcon *
2087 cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2088 {
2089         int rc, xid;
2090         struct cifs_tcon *tcon;
2091
2092         tcon = cifs_find_tcon(ses, ctx);
2093         if (tcon) {
2094                 /*
2095                  * tcon has refcount already incremented but we need to
2096                  * decrement extra ses reference gotten by caller (case b)
2097                  */
2098                 cifs_dbg(FYI, "Found match on UNC path\n");
2099                 cifs_put_smb_ses(ses);
2100                 return tcon;
2101         }
2102
2103         if (!ses->server->ops->tree_connect) {
2104                 rc = -ENOSYS;
2105                 goto out_fail;
2106         }
2107
2108         tcon = tconInfoAlloc();
2109         if (tcon == NULL) {
2110                 rc = -ENOMEM;
2111                 goto out_fail;
2112         }
2113
2114         if (ctx->snapshot_time) {
2115                 if (ses->server->vals->protocol_id == 0) {
2116                         cifs_dbg(VFS,
2117                              "Use SMB2 or later for snapshot mount option\n");
2118                         rc = -EOPNOTSUPP;
2119                         goto out_fail;
2120                 } else
2121                         tcon->snapshot_time = ctx->snapshot_time;
2122         }
2123
2124         if (ctx->handle_timeout) {
2125                 if (ses->server->vals->protocol_id == 0) {
2126                         cifs_dbg(VFS,
2127                              "Use SMB2.1 or later for handle timeout option\n");
2128                         rc = -EOPNOTSUPP;
2129                         goto out_fail;
2130                 } else
2131                         tcon->handle_timeout = ctx->handle_timeout;
2132         }
2133
2134         tcon->ses = ses;
2135         if (ctx->password) {
2136                 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2137                 if (!tcon->password) {
2138                         rc = -ENOMEM;
2139                         goto out_fail;
2140                 }
2141         }
2142
2143         if (ctx->seal) {
2144                 if (ses->server->vals->protocol_id == 0) {
2145                         cifs_dbg(VFS,
2146                                  "SMB3 or later required for encryption\n");
2147                         rc = -EOPNOTSUPP;
2148                         goto out_fail;
2149                 } else if (tcon->ses->server->capabilities &
2150                                         SMB2_GLOBAL_CAP_ENCRYPTION)
2151                         tcon->seal = true;
2152                 else {
2153                         cifs_dbg(VFS, "Encryption is not supported on share\n");
2154                         rc = -EOPNOTSUPP;
2155                         goto out_fail;
2156                 }
2157         }
2158
2159         if (ctx->linux_ext) {
2160                 if (ses->server->posix_ext_supported) {
2161                         tcon->posix_extensions = true;
2162                         pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2163                 } else {
2164                         cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2165                         rc = -EOPNOTSUPP;
2166                         goto out_fail;
2167                 }
2168         }
2169
2170         /*
2171          * BB Do we need to wrap session_mutex around this TCon call and Unix
2172          * SetFS as we do on SessSetup and reconnect?
2173          */
2174         xid = get_xid();
2175         rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2176                                             ctx->local_nls);
2177         free_xid(xid);
2178         cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2179         if (rc)
2180                 goto out_fail;
2181
2182         tcon->use_persistent = false;
2183         /* check if SMB2 or later, CIFS does not support persistent handles */
2184         if (ctx->persistent) {
2185                 if (ses->server->vals->protocol_id == 0) {
2186                         cifs_dbg(VFS,
2187                              "SMB3 or later required for persistent handles\n");
2188                         rc = -EOPNOTSUPP;
2189                         goto out_fail;
2190                 } else if (ses->server->capabilities &
2191                            SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2192                         tcon->use_persistent = true;
2193                 else /* persistent handles requested but not supported */ {
2194                         cifs_dbg(VFS,
2195                                 "Persistent handles not supported on share\n");
2196                         rc = -EOPNOTSUPP;
2197                         goto out_fail;
2198                 }
2199         } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2200              && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2201              && (ctx->nopersistent == false)) {
2202                 cifs_dbg(FYI, "enabling persistent handles\n");
2203                 tcon->use_persistent = true;
2204         } else if (ctx->resilient) {
2205                 if (ses->server->vals->protocol_id == 0) {
2206                         cifs_dbg(VFS,
2207                              "SMB2.1 or later required for resilient handles\n");
2208                         rc = -EOPNOTSUPP;
2209                         goto out_fail;
2210                 }
2211                 tcon->use_resilient = true;
2212         }
2213
2214         tcon->use_witness = false;
2215         if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2216                 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2217                         if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2218                                 /*
2219                                  * Set witness in use flag in first place
2220                                  * to retry registration in the echo task
2221                                  */
2222                                 tcon->use_witness = true;
2223                                 /* And try to register immediately */
2224                                 rc = cifs_swn_register(tcon);
2225                                 if (rc < 0) {
2226                                         cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2227                                         goto out_fail;
2228                                 }
2229                         } else {
2230                                 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2231                                 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2232                                 rc = -EOPNOTSUPP;
2233                                 goto out_fail;
2234                         }
2235                 } else {
2236                         cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2237                         rc = -EOPNOTSUPP;
2238                         goto out_fail;
2239                 }
2240         }
2241
2242         /* If the user really knows what they are doing they can override */
2243         if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2244                 if (ctx->cache_ro)
2245                         cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2246                 else if (ctx->cache_rw)
2247                         cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2248         }
2249
2250         if (ctx->no_lease) {
2251                 if (ses->server->vals->protocol_id == 0) {
2252                         cifs_dbg(VFS,
2253                                 "SMB2 or later required for nolease option\n");
2254                         rc = -EOPNOTSUPP;
2255                         goto out_fail;
2256                 } else
2257                         tcon->no_lease = ctx->no_lease;
2258         }
2259
2260         /*
2261          * We can have only one retry value for a connection to a share so for
2262          * resources mounted more than once to the same server share the last
2263          * value passed in for the retry flag is used.
2264          */
2265         tcon->retry = ctx->retry;
2266         tcon->nocase = ctx->nocase;
2267         if (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING)
2268                 tcon->nohandlecache = ctx->nohandlecache;
2269         else
2270                 tcon->nohandlecache = true;
2271         tcon->nodelete = ctx->nodelete;
2272         tcon->local_lease = ctx->local_lease;
2273         INIT_LIST_HEAD(&tcon->pending_opens);
2274
2275         spin_lock(&cifs_tcp_ses_lock);
2276         list_add(&tcon->tcon_list, &ses->tcon_list);
2277         spin_unlock(&cifs_tcp_ses_lock);
2278
2279         cifs_fscache_get_super_cookie(tcon);
2280
2281         return tcon;
2282
2283 out_fail:
2284         tconInfoFree(tcon);
2285         return ERR_PTR(rc);
2286 }
2287
2288 void
2289 cifs_put_tlink(struct tcon_link *tlink)
2290 {
2291         if (!tlink || IS_ERR(tlink))
2292                 return;
2293
2294         if (!atomic_dec_and_test(&tlink->tl_count) ||
2295             test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2296                 tlink->tl_time = jiffies;
2297                 return;
2298         }
2299
2300         if (!IS_ERR(tlink_tcon(tlink)))
2301                 cifs_put_tcon(tlink_tcon(tlink));
2302         kfree(tlink);
2303         return;
2304 }
2305
2306 static int
2307 compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2308 {
2309         struct cifs_sb_info *old = CIFS_SB(sb);
2310         struct cifs_sb_info *new = mnt_data->cifs_sb;
2311         unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2312         unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2313
2314         if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2315                 return 0;
2316
2317         if (old->mnt_cifs_serverino_autodisabled)
2318                 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2319
2320         if (oldflags != newflags)
2321                 return 0;
2322
2323         /*
2324          * We want to share sb only if we don't specify an r/wsize or
2325          * specified r/wsize is greater than or equal to existing one.
2326          */
2327         if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2328                 return 0;
2329
2330         if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2331                 return 0;
2332
2333         if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2334             !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2335                 return 0;
2336
2337         if (old->ctx->file_mode != new->ctx->file_mode ||
2338             old->ctx->dir_mode != new->ctx->dir_mode)
2339                 return 0;
2340
2341         if (strcmp(old->local_nls->charset, new->local_nls->charset))
2342                 return 0;
2343
2344         if (old->ctx->acregmax != new->ctx->acregmax)
2345                 return 0;
2346         if (old->ctx->acdirmax != new->ctx->acdirmax)
2347                 return 0;
2348
2349         return 1;
2350 }
2351
2352 static int
2353 match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2354 {
2355         struct cifs_sb_info *old = CIFS_SB(sb);
2356         struct cifs_sb_info *new = mnt_data->cifs_sb;
2357         bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2358                 old->prepath;
2359         bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2360                 new->prepath;
2361
2362         if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2363                 return 1;
2364         else if (!old_set && !new_set)
2365                 return 1;
2366
2367         return 0;
2368 }
2369
2370 int
2371 cifs_match_super(struct super_block *sb, void *data)
2372 {
2373         struct cifs_mnt_data *mnt_data = (struct cifs_mnt_data *)data;
2374         struct smb3_fs_context *ctx;
2375         struct cifs_sb_info *cifs_sb;
2376         struct TCP_Server_Info *tcp_srv;
2377         struct cifs_ses *ses;
2378         struct cifs_tcon *tcon;
2379         struct tcon_link *tlink;
2380         int rc = 0;
2381
2382         spin_lock(&cifs_tcp_ses_lock);
2383         cifs_sb = CIFS_SB(sb);
2384         tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2385         if (IS_ERR(tlink)) {
2386                 spin_unlock(&cifs_tcp_ses_lock);
2387                 return rc;
2388         }
2389         tcon = tlink_tcon(tlink);
2390         ses = tcon->ses;
2391         tcp_srv = ses->server;
2392
2393         ctx = mnt_data->ctx;
2394
2395         if (!match_server(tcp_srv, ctx) ||
2396             !match_session(ses, ctx) ||
2397             !match_tcon(tcon, ctx) ||
2398             !match_prepath(sb, mnt_data)) {
2399                 rc = 0;
2400                 goto out;
2401         }
2402
2403         rc = compare_mount_options(sb, mnt_data);
2404 out:
2405         spin_unlock(&cifs_tcp_ses_lock);
2406         cifs_put_tlink(tlink);
2407         return rc;
2408 }
2409
2410 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2411 static struct lock_class_key cifs_key[2];
2412 static struct lock_class_key cifs_slock_key[2];
2413
2414 static inline void
2415 cifs_reclassify_socket4(struct socket *sock)
2416 {
2417         struct sock *sk = sock->sk;
2418         BUG_ON(!sock_allow_reclassification(sk));
2419         sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2420                 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2421 }
2422
2423 static inline void
2424 cifs_reclassify_socket6(struct socket *sock)
2425 {
2426         struct sock *sk = sock->sk;
2427         BUG_ON(!sock_allow_reclassification(sk));
2428         sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2429                 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2430 }
2431 #else
2432 static inline void
2433 cifs_reclassify_socket4(struct socket *sock)
2434 {
2435 }
2436
2437 static inline void
2438 cifs_reclassify_socket6(struct socket *sock)
2439 {
2440 }
2441 #endif
2442
2443 /* See RFC1001 section 14 on representation of Netbios names */
2444 static void rfc1002mangle(char *target, char *source, unsigned int length)
2445 {
2446         unsigned int i, j;
2447
2448         for (i = 0, j = 0; i < (length); i++) {
2449                 /* mask a nibble at a time and encode */
2450                 target[j] = 'A' + (0x0F & (source[i] >> 4));
2451                 target[j+1] = 'A' + (0x0F & source[i]);
2452                 j += 2;
2453         }
2454
2455 }
2456
2457 static int
2458 bind_socket(struct TCP_Server_Info *server)
2459 {
2460         int rc = 0;
2461         if (server->srcaddr.ss_family != AF_UNSPEC) {
2462                 /* Bind to the specified local IP address */
2463                 struct socket *socket = server->ssocket;
2464                 rc = socket->ops->bind(socket,
2465                                        (struct sockaddr *) &server->srcaddr,
2466                                        sizeof(server->srcaddr));
2467                 if (rc < 0) {
2468                         struct sockaddr_in *saddr4;
2469                         struct sockaddr_in6 *saddr6;
2470                         saddr4 = (struct sockaddr_in *)&server->srcaddr;
2471                         saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2472                         if (saddr6->sin6_family == AF_INET6)
2473                                 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2474                                          &saddr6->sin6_addr, rc);
2475                         else
2476                                 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2477                                          &saddr4->sin_addr.s_addr, rc);
2478                 }
2479         }
2480         return rc;
2481 }
2482
2483 static int
2484 ip_rfc1001_connect(struct TCP_Server_Info *server)
2485 {
2486         int rc = 0;
2487         /*
2488          * some servers require RFC1001 sessinit before sending
2489          * negprot - BB check reconnection in case where second
2490          * sessinit is sent but no second negprot
2491          */
2492         struct rfc1002_session_packet *ses_init_buf;
2493         struct smb_hdr *smb_buf;
2494         ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
2495                                GFP_KERNEL);
2496         if (ses_init_buf) {
2497                 ses_init_buf->trailer.session_req.called_len = 32;
2498
2499                 if (server->server_RFC1001_name[0] != 0)
2500                         rfc1002mangle(ses_init_buf->trailer.
2501                                       session_req.called_name,
2502                                       server->server_RFC1001_name,
2503                                       RFC1001_NAME_LEN_WITH_NULL);
2504                 else
2505                         rfc1002mangle(ses_init_buf->trailer.
2506                                       session_req.called_name,
2507                                       DEFAULT_CIFS_CALLED_NAME,
2508                                       RFC1001_NAME_LEN_WITH_NULL);
2509
2510                 ses_init_buf->trailer.session_req.calling_len = 32;
2511
2512                 /*
2513                  * calling name ends in null (byte 16) from old smb
2514                  * convention.
2515                  */
2516                 if (server->workstation_RFC1001_name[0] != 0)
2517                         rfc1002mangle(ses_init_buf->trailer.
2518                                       session_req.calling_name,
2519                                       server->workstation_RFC1001_name,
2520                                       RFC1001_NAME_LEN_WITH_NULL);
2521                 else
2522                         rfc1002mangle(ses_init_buf->trailer.
2523                                       session_req.calling_name,
2524                                       "LINUX_CIFS_CLNT",
2525                                       RFC1001_NAME_LEN_WITH_NULL);
2526
2527                 ses_init_buf->trailer.session_req.scope1 = 0;
2528                 ses_init_buf->trailer.session_req.scope2 = 0;
2529                 smb_buf = (struct smb_hdr *)ses_init_buf;
2530
2531                 /* sizeof RFC1002_SESSION_REQUEST with no scope */
2532                 smb_buf->smb_buf_length = cpu_to_be32(0x81000044);
2533                 rc = smb_send(server, smb_buf, 0x44);
2534                 kfree(ses_init_buf);
2535                 /*
2536                  * RFC1001 layer in at least one server
2537                  * requires very short break before negprot
2538                  * presumably because not expecting negprot
2539                  * to follow so fast.  This is a simple
2540                  * solution that works without
2541                  * complicating the code and causes no
2542                  * significant slowing down on mount
2543                  * for everyone else
2544                  */
2545                 usleep_range(1000, 2000);
2546         }
2547         /*
2548          * else the negprot may still work without this
2549          * even though malloc failed
2550          */
2551
2552         return rc;
2553 }
2554
2555 static int
2556 generic_ip_connect(struct TCP_Server_Info *server)
2557 {
2558         int rc = 0;
2559         __be16 sport;
2560         int slen, sfamily;
2561         struct socket *socket = server->ssocket;
2562         struct sockaddr *saddr;
2563
2564         saddr = (struct sockaddr *) &server->dstaddr;
2565
2566         if (server->dstaddr.ss_family == AF_INET6) {
2567                 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
2568
2569                 sport = ipv6->sin6_port;
2570                 slen = sizeof(struct sockaddr_in6);
2571                 sfamily = AF_INET6;
2572                 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
2573                                 ntohs(sport));
2574         } else {
2575                 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
2576
2577                 sport = ipv4->sin_port;
2578                 slen = sizeof(struct sockaddr_in);
2579                 sfamily = AF_INET;
2580                 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
2581                                 ntohs(sport));
2582         }
2583
2584         if (socket == NULL) {
2585                 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
2586                                    IPPROTO_TCP, &socket, 1);
2587                 if (rc < 0) {
2588                         cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
2589                         server->ssocket = NULL;
2590                         return rc;
2591                 }
2592
2593                 /* BB other socket options to set KEEPALIVE, NODELAY? */
2594                 cifs_dbg(FYI, "Socket created\n");
2595                 server->ssocket = socket;
2596                 socket->sk->sk_allocation = GFP_NOFS;
2597                 if (sfamily == AF_INET6)
2598                         cifs_reclassify_socket6(socket);
2599                 else
2600                         cifs_reclassify_socket4(socket);
2601         }
2602
2603         rc = bind_socket(server);
2604         if (rc < 0)
2605                 return rc;
2606
2607         /*
2608          * Eventually check for other socket options to change from
2609          * the default. sock_setsockopt not used because it expects
2610          * user space buffer
2611          */
2612         socket->sk->sk_rcvtimeo = 7 * HZ;
2613         socket->sk->sk_sndtimeo = 5 * HZ;
2614
2615         /* make the bufsizes depend on wsize/rsize and max requests */
2616         if (server->noautotune) {
2617                 if (socket->sk->sk_sndbuf < (200 * 1024))
2618                         socket->sk->sk_sndbuf = 200 * 1024;
2619                 if (socket->sk->sk_rcvbuf < (140 * 1024))
2620                         socket->sk->sk_rcvbuf = 140 * 1024;
2621         }
2622
2623         if (server->tcp_nodelay)
2624                 tcp_sock_set_nodelay(socket->sk);
2625
2626         cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
2627                  socket->sk->sk_sndbuf,
2628                  socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
2629
2630         rc = socket->ops->connect(socket, saddr, slen,
2631                                   server->noblockcnt ? O_NONBLOCK : 0);
2632         /*
2633          * When mounting SMB root file systems, we do not want to block in
2634          * connect. Otherwise bail out and then let cifs_reconnect() perform
2635          * reconnect failover - if possible.
2636          */
2637         if (server->noblockcnt && rc == -EINPROGRESS)
2638                 rc = 0;
2639         if (rc < 0) {
2640                 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
2641                 sock_release(socket);
2642                 server->ssocket = NULL;
2643                 return rc;
2644         }
2645
2646         if (sport == htons(RFC1001_PORT))
2647                 rc = ip_rfc1001_connect(server);
2648
2649         return rc;
2650 }
2651
2652 static int
2653 ip_connect(struct TCP_Server_Info *server)
2654 {
2655         __be16 *sport;
2656         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2657         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2658
2659         if (server->dstaddr.ss_family == AF_INET6)
2660                 sport = &addr6->sin6_port;
2661         else
2662                 sport = &addr->sin_port;
2663
2664         if (*sport == 0) {
2665                 int rc;
2666
2667                 /* try with 445 port at first */
2668                 *sport = htons(CIFS_PORT);
2669
2670                 rc = generic_ip_connect(server);
2671                 if (rc >= 0)
2672                         return rc;
2673
2674                 /* if it failed, try with 139 port */
2675                 *sport = htons(RFC1001_PORT);
2676         }
2677
2678         return generic_ip_connect(server);
2679 }
2680
2681 void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
2682                           struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
2683 {
2684         /*
2685          * If we are reconnecting then should we check to see if
2686          * any requested capabilities changed locally e.g. via
2687          * remount but we can not do much about it here
2688          * if they have (even if we could detect it by the following)
2689          * Perhaps we could add a backpointer to array of sb from tcon
2690          * or if we change to make all sb to same share the same
2691          * sb as NFS - then we only have one backpointer to sb.
2692          * What if we wanted to mount the server share twice once with
2693          * and once without posixacls or posix paths?
2694          */
2695         __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
2696
2697         if (ctx && ctx->no_linux_ext) {
2698                 tcon->fsUnixInfo.Capability = 0;
2699                 tcon->unix_ext = 0; /* Unix Extensions disabled */
2700                 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
2701                 return;
2702         } else if (ctx)
2703                 tcon->unix_ext = 1; /* Unix Extensions supported */
2704
2705         if (!tcon->unix_ext) {
2706                 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
2707                 return;
2708         }
2709
2710         if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
2711                 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
2712                 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
2713                 /*
2714                  * check for reconnect case in which we do not
2715                  * want to change the mount behavior if we can avoid it
2716                  */
2717                 if (ctx == NULL) {
2718                         /*
2719                          * turn off POSIX ACL and PATHNAMES if not set
2720                          * originally at mount time
2721                          */
2722                         if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
2723                                 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
2724                         if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
2725                                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
2726                                         cifs_dbg(VFS, "POSIXPATH support change\n");
2727                                 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
2728                         } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
2729                                 cifs_dbg(VFS, "possible reconnect error\n");
2730                                 cifs_dbg(VFS, "server disabled POSIX path support\n");
2731                         }
2732                 }
2733
2734                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
2735                         cifs_dbg(VFS, "per-share encryption not supported yet\n");
2736
2737                 cap &= CIFS_UNIX_CAP_MASK;
2738                 if (ctx && ctx->no_psx_acl)
2739                         cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
2740                 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
2741                         cifs_dbg(FYI, "negotiated posix acl support\n");
2742                         if (cifs_sb)
2743                                 cifs_sb->mnt_cifs_flags |=
2744                                         CIFS_MOUNT_POSIXACL;
2745                 }
2746
2747                 if (ctx && ctx->posix_paths == 0)
2748                         cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
2749                 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
2750                         cifs_dbg(FYI, "negotiate posix pathnames\n");
2751                         if (cifs_sb)
2752                                 cifs_sb->mnt_cifs_flags |=
2753                                         CIFS_MOUNT_POSIX_PATHS;
2754                 }
2755
2756                 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
2757 #ifdef CONFIG_CIFS_DEBUG2
2758                 if (cap & CIFS_UNIX_FCNTL_CAP)
2759                         cifs_dbg(FYI, "FCNTL cap\n");
2760                 if (cap & CIFS_UNIX_EXTATTR_CAP)
2761                         cifs_dbg(FYI, "EXTATTR cap\n");
2762                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
2763                         cifs_dbg(FYI, "POSIX path cap\n");
2764                 if (cap & CIFS_UNIX_XATTR_CAP)
2765                         cifs_dbg(FYI, "XATTR cap\n");
2766                 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
2767                         cifs_dbg(FYI, "POSIX ACL cap\n");
2768                 if (cap & CIFS_UNIX_LARGE_READ_CAP)
2769                         cifs_dbg(FYI, "very large read cap\n");
2770                 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
2771                         cifs_dbg(FYI, "very large write cap\n");
2772                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
2773                         cifs_dbg(FYI, "transport encryption cap\n");
2774                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
2775                         cifs_dbg(FYI, "mandatory transport encryption cap\n");
2776 #endif /* CIFS_DEBUG2 */
2777                 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
2778                         if (ctx == NULL)
2779                                 cifs_dbg(FYI, "resetting capabilities failed\n");
2780                         else
2781                                 cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");
2782
2783                 }
2784         }
2785 }
2786
2787 int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
2788 {
2789         struct smb3_fs_context *ctx = cifs_sb->ctx;
2790
2791         INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
2792
2793         spin_lock_init(&cifs_sb->tlink_tree_lock);
2794         cifs_sb->tlink_tree = RB_ROOT;
2795
2796         cifs_dbg(FYI, "file mode: %04ho  dir mode: %04ho\n",
2797                  ctx->file_mode, ctx->dir_mode);
2798
2799         /* this is needed for ASCII cp to Unicode converts */
2800         if (ctx->iocharset == NULL) {
2801                 /* load_nls_default cannot return null */
2802                 cifs_sb->local_nls = load_nls_default();
2803         } else {
2804                 cifs_sb->local_nls = load_nls(ctx->iocharset);
2805                 if (cifs_sb->local_nls == NULL) {
2806                         cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
2807                                  ctx->iocharset);
2808                         return -ELIBACC;
2809                 }
2810         }
2811         ctx->local_nls = cifs_sb->local_nls;
2812
2813         smb3_update_mnt_flags(cifs_sb);
2814
2815         if (ctx->direct_io)
2816                 cifs_dbg(FYI, "mounting share using direct i/o\n");
2817         if (ctx->cache_ro) {
2818                 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
2819                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
2820         } else if (ctx->cache_rw) {
2821                 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
2822                 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
2823                                             CIFS_MOUNT_RW_CACHE);
2824         }
2825
2826         if ((ctx->cifs_acl) && (ctx->dynperm))
2827                 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
2828
2829         if (ctx->prepath) {
2830                 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
2831                 if (cifs_sb->prepath == NULL)
2832                         return -ENOMEM;
2833                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
2834         }
2835
2836         return 0;
2837 }
2838
2839 /* Release all succeed connections */
2840 static inline void mount_put_conns(struct cifs_sb_info *cifs_sb,
2841                                    unsigned int xid,
2842                                    struct TCP_Server_Info *server,
2843                                    struct cifs_ses *ses, struct cifs_tcon *tcon)
2844 {
2845         int rc = 0;
2846
2847         if (tcon)
2848                 cifs_put_tcon(tcon);
2849         else if (ses)
2850                 cifs_put_smb_ses(ses);
2851         else if (server)
2852                 cifs_put_tcp_session(server, 0);
2853         cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
2854         free_xid(xid);
2855 }
2856
2857 /* Get connections for tcp, ses and tcon */
2858 static int mount_get_conns(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
2859                            unsigned int *xid,
2860                            struct TCP_Server_Info **nserver,
2861                            struct cifs_ses **nses, struct cifs_tcon **ntcon)
2862 {
2863         int rc = 0;
2864         struct TCP_Server_Info *server;
2865         struct cifs_ses *ses;
2866         struct cifs_tcon *tcon;
2867
2868         *nserver = NULL;
2869         *nses = NULL;
2870         *ntcon = NULL;
2871
2872         *xid = get_xid();
2873
2874         /* get a reference to a tcp session */
2875         server = cifs_get_tcp_session(ctx);
2876         if (IS_ERR(server)) {
2877                 rc = PTR_ERR(server);
2878                 return rc;
2879         }
2880
2881         *nserver = server;
2882
2883         /* get a reference to a SMB session */
2884         ses = cifs_get_smb_ses(server, ctx);
2885         if (IS_ERR(ses)) {
2886                 rc = PTR_ERR(ses);
2887                 return rc;
2888         }
2889
2890         *nses = ses;
2891
2892         if ((ctx->persistent == true) && (!(ses->server->capabilities &
2893                                             SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
2894                 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
2895                 return -EOPNOTSUPP;
2896         }
2897
2898         /* search for existing tcon to this server share */
2899         tcon = cifs_get_tcon(ses, ctx);
2900         if (IS_ERR(tcon)) {
2901                 rc = PTR_ERR(tcon);
2902                 return rc;
2903         }
2904
2905         *ntcon = tcon;
2906
2907         /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
2908         if (tcon->posix_extensions)
2909                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
2910
2911         /* tell server which Unix caps we support */
2912         if (cap_unix(tcon->ses)) {
2913                 /*
2914                  * reset of caps checks mount to see if unix extensions disabled
2915                  * for just this mount.
2916                  */
2917                 reset_cifs_unix_caps(*xid, tcon, cifs_sb, ctx);
2918                 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
2919                     (le64_to_cpu(tcon->fsUnixInfo.Capability) &
2920                      CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP))
2921                         return -EACCES;
2922         } else
2923                 tcon->unix_ext = 0; /* server does not support them */
2924
2925         /* do not care if a following call succeed - informational */
2926         if (!tcon->pipe && server->ops->qfs_tcon) {
2927                 server->ops->qfs_tcon(*xid, tcon, cifs_sb);
2928                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
2929                         if (tcon->fsDevInfo.DeviceCharacteristics &
2930                             cpu_to_le32(FILE_READ_ONLY_DEVICE))
2931                                 cifs_dbg(VFS, "mounted to read only share\n");
2932                         else if ((cifs_sb->mnt_cifs_flags &
2933                                   CIFS_MOUNT_RW_CACHE) == 0)
2934                                 cifs_dbg(VFS, "read only mount of RW share\n");
2935                         /* no need to log a RW mount of a typical RW share */
2936                 }
2937         }
2938
2939         /*
2940          * Clamp the rsize/wsize mount arguments if they are too big for the server
2941          * and set the rsize/wsize to the negotiated values if not passed in by
2942          * the user on mount
2943          */
2944         if ((cifs_sb->ctx->wsize == 0) ||
2945             (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
2946                 cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
2947         if ((cifs_sb->ctx->rsize == 0) ||
2948             (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
2949                 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
2950
2951         return 0;
2952 }
2953
2954 static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
2955                              struct cifs_tcon *tcon)
2956 {
2957         struct tcon_link *tlink;
2958
2959         /* hang the tcon off of the superblock */
2960         tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
2961         if (tlink == NULL)
2962                 return -ENOMEM;
2963
2964         tlink->tl_uid = ses->linux_uid;
2965         tlink->tl_tcon = tcon;
2966         tlink->tl_time = jiffies;
2967         set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
2968         set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
2969
2970         cifs_sb->master_tlink = tlink;
2971         spin_lock(&cifs_sb->tlink_tree_lock);
2972         tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
2973         spin_unlock(&cifs_sb->tlink_tree_lock);
2974
2975         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
2976                                 TLINK_IDLE_EXPIRE);
2977         return 0;
2978 }
2979
2980 #ifdef CONFIG_CIFS_DFS_UPCALL
2981 static int mount_get_dfs_conns(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
2982                                unsigned int *xid, struct TCP_Server_Info **nserver,
2983                                struct cifs_ses **nses, struct cifs_tcon **ntcon)
2984 {
2985         int rc;
2986
2987         ctx->nosharesock = true;
2988         rc = mount_get_conns(ctx, cifs_sb, xid, nserver, nses, ntcon);
2989         if (*nserver) {
2990                 cifs_dbg(FYI, "%s: marking tcp session as a dfs connection\n", __func__);
2991                 spin_lock(&cifs_tcp_ses_lock);
2992                 (*nserver)->is_dfs_conn = true;
2993                 spin_unlock(&cifs_tcp_ses_lock);
2994         }
2995         return rc;
2996 }
2997
2998 /*
2999  * cifs_build_path_to_root returns full path to root when we do not have an
3000  * existing connection (tcon)
3001  */
3002 static char *
3003 build_unc_path_to_root(const struct smb3_fs_context *ctx,
3004                        const struct cifs_sb_info *cifs_sb, bool useppath)
3005 {
3006         char *full_path, *pos;
3007         unsigned int pplen = useppath && ctx->prepath ?
3008                 strlen(ctx->prepath) + 1 : 0;
3009         unsigned int unc_len = strnlen(ctx->UNC, MAX_TREE_SIZE + 1);
3010
3011         if (unc_len > MAX_TREE_SIZE)
3012                 return ERR_PTR(-EINVAL);
3013
3014         full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
3015         if (full_path == NULL)
3016                 return ERR_PTR(-ENOMEM);
3017
3018         memcpy(full_path, ctx->UNC, unc_len);
3019         pos = full_path + unc_len;
3020
3021         if (pplen) {
3022                 *pos = CIFS_DIR_SEP(cifs_sb);
3023                 memcpy(pos + 1, ctx->prepath, pplen);
3024                 pos += pplen;
3025         }
3026
3027         *pos = '\0'; /* add trailing null */
3028         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
3029         cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
3030         return full_path;
3031 }
3032
3033 /**
3034  * expand_dfs_referral - Perform a dfs referral query and update the cifs_sb
3035  *
3036  * If a referral is found, cifs_sb->ctx->mount_options will be (re-)allocated
3037  * to a string containing updated options for the submount.  Otherwise it
3038  * will be left untouched.
3039  *
3040  * Returns the rc from get_dfs_path to the caller, which can be used to
3041  * determine whether there were referrals.
3042  */
3043 static int
3044 expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
3045                     struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
3046                     char *ref_path)
3047 {
3048         int rc;
3049         struct dfs_info3_param referral = {0};
3050         char *full_path = NULL, *mdata = NULL;
3051
3052         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
3053                 return -EREMOTE;
3054
3055         full_path = build_unc_path_to_root(ctx, cifs_sb, true);
3056         if (IS_ERR(full_path))
3057                 return PTR_ERR(full_path);
3058
3059         rc = dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb),
3060                             ref_path, &referral, NULL);
3061         if (!rc) {
3062                 char *fake_devname = NULL;
3063
3064                 mdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options,
3065                                                    full_path + 1, &referral,
3066                                                    &fake_devname);
3067                 free_dfs_info_param(&referral);
3068
3069                 if (IS_ERR(mdata)) {
3070                         rc = PTR_ERR(mdata);
3071                         mdata = NULL;
3072                 } else {
3073                         /*
3074                          * We can not clear out the whole structure since we
3075                          * no longer have an explicit function to parse
3076                          * a mount-string. Instead we need to clear out the
3077                          * individual fields that are no longer valid.
3078                          */
3079                         kfree(ctx->prepath);
3080                         ctx->prepath = NULL;
3081                         rc = cifs_setup_volume_info(ctx, mdata, fake_devname);
3082                 }
3083                 kfree(fake_devname);
3084                 kfree(cifs_sb->ctx->mount_options);
3085                 cifs_sb->ctx->mount_options = mdata;
3086         }
3087         kfree(full_path);
3088         return rc;
3089 }
3090
3091 static int get_next_dfs_tgt(struct dfs_cache_tgt_list *tgt_list,
3092                             struct dfs_cache_tgt_iterator **tgt_it)
3093 {
3094         if (!*tgt_it)
3095                 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
3096         else
3097                 *tgt_it = dfs_cache_get_next_tgt(tgt_list, *tgt_it);
3098         return !*tgt_it ? -EHOSTDOWN : 0;
3099 }
3100
3101 static int update_vol_info(const struct dfs_cache_tgt_iterator *tgt_it,
3102                            struct smb3_fs_context *fake_ctx, struct smb3_fs_context *ctx)
3103 {
3104         const char *tgt = dfs_cache_get_tgt_name(tgt_it);
3105         int len = strlen(tgt) + 2;
3106         char *new_unc;
3107
3108         new_unc = kmalloc(len, GFP_KERNEL);
3109         if (!new_unc)
3110                 return -ENOMEM;
3111         scnprintf(new_unc, len, "\\%s", tgt);
3112
3113         kfree(ctx->UNC);
3114         ctx->UNC = new_unc;
3115
3116         if (fake_ctx->prepath) {
3117                 kfree(ctx->prepath);
3118                 ctx->prepath = fake_ctx->prepath;
3119                 fake_ctx->prepath = NULL;
3120         }
3121         memcpy(&ctx->dstaddr, &fake_ctx->dstaddr, sizeof(ctx->dstaddr));
3122
3123         return 0;
3124 }
3125
3126 static int do_dfs_failover(const char *path, const char *full_path, struct cifs_sb_info *cifs_sb,
3127                            struct smb3_fs_context *ctx, struct cifs_ses *root_ses,
3128                            unsigned int *xid, struct TCP_Server_Info **server,
3129                            struct cifs_ses **ses, struct cifs_tcon **tcon)
3130 {
3131         int rc;
3132         char *npath = NULL;
3133         struct dfs_cache_tgt_list tgt_list = DFS_CACHE_TGT_LIST_INIT(tgt_list);
3134         struct dfs_cache_tgt_iterator *tgt_it = NULL;
3135         struct smb3_fs_context tmp_ctx = {NULL};
3136
3137         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
3138                 return -EOPNOTSUPP;
3139
3140         npath = dfs_cache_canonical_path(path, cifs_sb->local_nls, cifs_remap(cifs_sb));
3141         if (IS_ERR(npath))
3142                 return PTR_ERR(npath);
3143
3144         cifs_dbg(FYI, "%s: path=%s full_path=%s\n", __func__, npath, full_path);
3145
3146         rc = dfs_cache_noreq_find(npath, NULL, &tgt_list);
3147         if (rc)
3148                 goto out;
3149         /*
3150          * We use a 'tmp_ctx' here because we need pass it down to the mount_{get,put} functions to
3151          * test connection against new DFS targets.
3152          */
3153         rc = smb3_fs_context_dup(&tmp_ctx, ctx);
3154         if (rc)
3155                 goto out;
3156
3157         for (;;) {
3158                 struct dfs_info3_param ref = {0};
3159                 char *fake_devname = NULL, *mdata = NULL;
3160
3161                 /* Get next DFS target server - if any */
3162                 rc = get_next_dfs_tgt(&tgt_list, &tgt_it);
3163                 if (rc)
3164                         break;
3165
3166                 rc = dfs_cache_get_tgt_referral(npath, tgt_it, &ref);
3167                 if (rc)
3168                         break;
3169
3170                 cifs_dbg(FYI, "%s: old ctx: UNC=%s prepath=%s\n", __func__, tmp_ctx.UNC,
3171                          tmp_ctx.prepath);
3172
3173                 mdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options, full_path + 1, &ref,
3174                                                    &fake_devname);
3175                 free_dfs_info_param(&ref);
3176
3177                 if (IS_ERR(mdata)) {
3178                         rc = PTR_ERR(mdata);
3179                         mdata = NULL;
3180                 } else
3181                         rc = cifs_setup_volume_info(&tmp_ctx, mdata, fake_devname);
3182
3183                 kfree(mdata);
3184                 kfree(fake_devname);
3185
3186                 if (rc)
3187                         break;
3188
3189                 cifs_dbg(FYI, "%s: new ctx: UNC=%s prepath=%s\n", __func__, tmp_ctx.UNC,
3190                          tmp_ctx.prepath);
3191
3192                 mount_put_conns(cifs_sb, *xid, *server, *ses, *tcon);
3193                 rc = mount_get_dfs_conns(&tmp_ctx, cifs_sb, xid, server, ses, tcon);
3194                 if (!rc || (*server && *ses)) {
3195                         /*
3196                          * We were able to connect to new target server. Update current context with
3197                          * new target server.
3198                          */
3199                         rc = update_vol_info(tgt_it, &tmp_ctx, ctx);
3200                         break;
3201                 }
3202         }
3203         if (!rc) {
3204                 cifs_dbg(FYI, "%s: final ctx: UNC=%s prepath=%s\n", __func__, tmp_ctx.UNC,
3205                          tmp_ctx.prepath);
3206                 /*
3207                  * Update DFS target hint in DFS referral cache with the target server we
3208                  * successfully reconnected to.
3209                  */
3210                 rc = dfs_cache_update_tgthint(*xid, root_ses ? root_ses : *ses, cifs_sb->local_nls,
3211                                               cifs_remap(cifs_sb), path, tgt_it);
3212         }
3213
3214 out:
3215         kfree(npath);
3216         smb3_cleanup_fs_context_contents(&tmp_ctx);
3217         dfs_cache_free_tgts(&tgt_list);
3218         return rc;
3219 }
3220 #endif
3221
3222 /* TODO: all callers to this are broken. We are not parsing mount_options here
3223  * we should pass a clone of the original context?
3224  */
3225 int
3226 cifs_setup_volume_info(struct smb3_fs_context *ctx, const char *mntopts, const char *devname)
3227 {
3228         int rc;
3229
3230         if (devname) {
3231                 cifs_dbg(FYI, "%s: devname=%s\n", __func__, devname);
3232                 rc = smb3_parse_devname(devname, ctx);
3233                 if (rc) {
3234                         cifs_dbg(VFS, "%s: failed to parse %s: %d\n", __func__, devname, rc);
3235                         return rc;
3236                 }
3237         }
3238
3239         if (mntopts) {
3240                 char *ip;
3241
3242                 rc = smb3_parse_opt(mntopts, "ip", &ip);
3243                 if (rc) {
3244                         cifs_dbg(VFS, "%s: failed to parse ip options: %d\n", __func__, rc);
3245                         return rc;
3246                 }
3247
3248                 rc = cifs_convert_address((struct sockaddr *)&ctx->dstaddr, ip, strlen(ip));
3249                 kfree(ip);
3250                 if (!rc) {
3251                         cifs_dbg(VFS, "%s: failed to convert ip address\n", __func__);
3252                         return -EINVAL;
3253                 }
3254         }
3255
3256         if (ctx->nullauth) {
3257                 cifs_dbg(FYI, "Anonymous login\n");
3258                 kfree(ctx->username);
3259                 ctx->username = NULL;
3260         } else if (ctx->username) {
3261                 /* BB fixme parse for domain name here */
3262                 cifs_dbg(FYI, "Username: %s\n", ctx->username);
3263         } else {
3264                 cifs_dbg(VFS, "No username specified\n");
3265         /* In userspace mount helper we can get user name from alternate
3266            locations such as env variables and files on disk */
3267                 return -EINVAL;
3268         }
3269
3270         return 0;
3271 }
3272
3273 static int
3274 cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3275                                         unsigned int xid,
3276                                         struct cifs_tcon *tcon,
3277                                         struct cifs_sb_info *cifs_sb,
3278                                         char *full_path,
3279                                         int added_treename)
3280 {
3281         int rc;
3282         char *s;
3283         char sep, tmp;
3284         int skip = added_treename ? 1 : 0;
3285
3286         sep = CIFS_DIR_SEP(cifs_sb);
3287         s = full_path;
3288
3289         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3290         while (rc == 0) {
3291                 /* skip separators */
3292                 while (*s == sep)
3293                         s++;
3294                 if (!*s)
3295                         break;
3296                 /* next separator */
3297                 while (*s && *s != sep)
3298                         s++;
3299                 /*
3300                  * if the treename is added, we then have to skip the first
3301                  * part within the separators
3302                  */
3303                 if (skip) {
3304                         skip = 0;
3305                         continue;
3306                 }
3307                 /*
3308                  * temporarily null-terminate the path at the end of
3309                  * the current component
3310                  */
3311                 tmp = *s;
3312                 *s = 0;
3313                 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3314                                                      full_path);
3315                 *s = tmp;
3316         }
3317         return rc;
3318 }
3319
3320 /*
3321  * Check if path is remote (e.g. a DFS share). Return -EREMOTE if it is,
3322  * otherwise 0.
3323  */
3324 static int is_path_remote(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx,
3325                           const unsigned int xid,
3326                           struct TCP_Server_Info *server,
3327                           struct cifs_tcon *tcon)
3328 {
3329         int rc;
3330         char *full_path;
3331
3332         if (!server->ops->is_path_accessible)
3333                 return -EOPNOTSUPP;
3334
3335         /*
3336          * cifs_build_path_to_root works only when we have a valid tcon
3337          */
3338         full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3339                                             tcon->Flags & SMB_SHARE_IS_IN_DFS);
3340         if (full_path == NULL)
3341                 return -ENOMEM;
3342
3343         cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3344
3345         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3346                                              full_path);
3347         if (rc != 0 && rc != -EREMOTE) {
3348                 kfree(full_path);
3349                 return rc;
3350         }
3351
3352         if (rc != -EREMOTE) {
3353                 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3354                         cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3355                 if (rc != 0) {
3356                         cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3357                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3358                         rc = 0;
3359                 }
3360         }
3361
3362         kfree(full_path);
3363         return rc;
3364 }
3365
3366 #ifdef CONFIG_CIFS_DFS_UPCALL
3367 static void set_root_ses(struct cifs_sb_info *cifs_sb, const uuid_t *mount_id, struct cifs_ses *ses,
3368                          struct cifs_ses **root_ses)
3369 {
3370         if (ses) {
3371                 spin_lock(&cifs_tcp_ses_lock);
3372                 ses->ses_count++;
3373                 spin_unlock(&cifs_tcp_ses_lock);
3374                 dfs_cache_add_refsrv_session(mount_id, ses);
3375         }
3376         *root_ses = ses;
3377 }
3378
3379 /* Set up next dfs prefix path in @dfs_path */
3380 static int next_dfs_prepath(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx,
3381                             const unsigned int xid, struct TCP_Server_Info *server,
3382                             struct cifs_tcon *tcon, char **dfs_path)
3383 {
3384         char *path, *npath;
3385         int added_treename = is_tcon_dfs(tcon);
3386         int rc;
3387
3388         path = cifs_build_path_to_root(ctx, cifs_sb, tcon, added_treename);
3389         if (!path)
3390                 return -ENOMEM;
3391
3392         rc = is_path_remote(cifs_sb, ctx, xid, server, tcon);
3393         if (rc == -EREMOTE) {
3394                 struct smb3_fs_context v = {NULL};
3395                 /* if @path contains a tree name, skip it in the prefix path */
3396                 if (added_treename) {
3397                         rc = smb3_parse_devname(path, &v);
3398                         if (rc)
3399                                 goto out;
3400                         npath = build_unc_path_to_root(&v, cifs_sb, true);
3401                         smb3_cleanup_fs_context_contents(&v);
3402                 } else {
3403                         v.UNC = ctx->UNC;
3404                         v.prepath = path + 1;
3405                         npath = build_unc_path_to_root(&v, cifs_sb, true);
3406                 }
3407
3408                 if (IS_ERR(npath)) {
3409                         rc = PTR_ERR(npath);
3410                         goto out;
3411                 }
3412
3413                 kfree(*dfs_path);
3414                 *dfs_path = npath;
3415                 rc = -EREMOTE;
3416         }
3417
3418 out:
3419         kfree(path);
3420         return rc;
3421 }
3422
3423 /* Check if resolved targets can handle any DFS referrals */
3424 static int is_referral_server(const char *ref_path, struct cifs_sb_info *cifs_sb,
3425                               struct cifs_tcon *tcon, bool *ref_server)
3426 {
3427         int rc;
3428         struct dfs_info3_param ref = {0};
3429
3430         cifs_dbg(FYI, "%s: ref_path=%s\n", __func__, ref_path);
3431
3432         if (is_tcon_dfs(tcon)) {
3433                 *ref_server = true;
3434         } else {
3435                 char *npath;
3436
3437                 npath = dfs_cache_canonical_path(ref_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
3438                 if (IS_ERR(npath))
3439                         return PTR_ERR(npath);
3440
3441                 rc = dfs_cache_noreq_find(npath, &ref, NULL);
3442                 kfree(npath);
3443                 if (rc) {
3444                         cifs_dbg(VFS, "%s: dfs_cache_noreq_find: failed (rc=%d)\n", __func__, rc);
3445                         return rc;
3446                 }
3447                 cifs_dbg(FYI, "%s: ref.flags=0x%x\n", __func__, ref.flags);
3448                 /*
3449                  * Check if all targets are capable of handling DFS referrals as per
3450                  * MS-DFSC 2.2.4 RESP_GET_DFS_REFERRAL.
3451                  */
3452                 *ref_server = !!(ref.flags & DFSREF_REFERRAL_SERVER);
3453                 free_dfs_info_param(&ref);
3454         }
3455         return 0;
3456 }
3457
3458 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3459 {
3460         int rc = 0;
3461         unsigned int xid;
3462         struct TCP_Server_Info *server = NULL;
3463         struct cifs_ses *ses = NULL, *root_ses = NULL;
3464         struct cifs_tcon *tcon = NULL;
3465         int count = 0;
3466         uuid_t mount_id = {0};
3467         char *ref_path = NULL, *full_path = NULL;
3468         char *oldmnt = NULL;
3469         bool ref_server = false;
3470
3471         rc = mount_get_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3472         /*
3473          * If called with 'nodfs' mount option, then skip DFS resolving.  Otherwise unconditionally
3474          * try to get an DFS referral (even cached) to determine whether it is an DFS mount.
3475          *
3476          * Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem
3477          * to respond with PATH_NOT_COVERED to requests that include the prefix.
3478          */
3479         if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) ||
3480             dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb), ctx->UNC + 1, NULL,
3481                            NULL)) {
3482                 if (rc)
3483                         goto error;
3484                 /* Check if it is fully accessible and then mount it */
3485                 rc = is_path_remote(cifs_sb, ctx, xid, server, tcon);
3486                 if (!rc)
3487                         goto out;
3488                 if (rc != -EREMOTE)
3489                         goto error;
3490         }
3491
3492         mount_put_conns(cifs_sb, xid, server, ses, tcon);
3493         /*
3494          * Ignore error check here because we may failover to other targets from cached a
3495          * referral.
3496          */
3497         (void)mount_get_dfs_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3498
3499         /* Get path of DFS root */
3500         ref_path = build_unc_path_to_root(ctx, cifs_sb, false);
3501         if (IS_ERR(ref_path)) {
3502                 rc = PTR_ERR(ref_path);
3503                 ref_path = NULL;
3504                 goto error;
3505         }
3506
3507         uuid_gen(&mount_id);
3508         set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
3509         do {
3510                 /* Save full path of last DFS path we used to resolve final target server */
3511                 kfree(full_path);
3512                 full_path = build_unc_path_to_root(ctx, cifs_sb, !!count);
3513                 if (IS_ERR(full_path)) {
3514                         rc = PTR_ERR(full_path);
3515                         full_path = NULL;
3516                         break;
3517                 }
3518                 /* Chase referral */
3519                 oldmnt = cifs_sb->ctx->mount_options;
3520                 rc = expand_dfs_referral(xid, root_ses, ctx, cifs_sb, ref_path + 1);
3521                 if (rc)
3522                         break;
3523                 /* Connect to new DFS target only if we were redirected */
3524                 if (oldmnt != cifs_sb->ctx->mount_options) {
3525                         mount_put_conns(cifs_sb, xid, server, ses, tcon);
3526                         rc = mount_get_dfs_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3527                 }
3528                 if (rc && !server && !ses) {
3529                         /* Failed to connect. Try to connect to other targets in the referral. */
3530                         rc = do_dfs_failover(ref_path + 1, full_path, cifs_sb, ctx, root_ses, &xid,
3531                                              &server, &ses, &tcon);
3532                 }
3533                 if (rc == -EACCES || rc == -EOPNOTSUPP || !server || !ses)
3534                         break;
3535                 if (!tcon)
3536                         continue;
3537
3538                 /* Make sure that requests go through new root servers */
3539                 rc = is_referral_server(ref_path + 1, cifs_sb, tcon, &ref_server);
3540                 if (rc)
3541                         break;
3542                 if (ref_server)
3543                         set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
3544
3545                 /* Get next dfs path and then continue chasing them if -EREMOTE */
3546                 rc = next_dfs_prepath(cifs_sb, ctx, xid, server, tcon, &ref_path);
3547                 /* Prevent recursion on broken link referrals */
3548                 if (rc == -EREMOTE && ++count > MAX_NESTED_LINKS)
3549                         rc = -ELOOP;
3550         } while (rc == -EREMOTE);
3551
3552         if (rc || !tcon || !ses)
3553                 goto error;
3554
3555         kfree(ref_path);
3556         /*
3557          * Store DFS full path in both superblock and tree connect structures.
3558          *
3559          * For DFS root mounts, the prefix path (cifs_sb->prepath) is preserved during reconnect so
3560          * only the root path is set in cifs_sb->origin_fullpath and tcon->dfs_path. And for DFS
3561          * links, the prefix path is included in both and may be changed during reconnect.  See
3562          * cifs_tree_connect().
3563          */
3564         ref_path = dfs_cache_canonical_path(full_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
3565         kfree(full_path);
3566         full_path = NULL;
3567
3568         if (IS_ERR(ref_path)) {
3569                 rc = PTR_ERR(ref_path);
3570                 ref_path = NULL;
3571                 goto error;
3572         }
3573         cifs_sb->origin_fullpath = ref_path;
3574
3575         ref_path = kstrdup(cifs_sb->origin_fullpath, GFP_KERNEL);
3576         if (!ref_path) {
3577                 rc = -ENOMEM;
3578                 goto error;
3579         }
3580         spin_lock(&cifs_tcp_ses_lock);
3581         tcon->dfs_path = ref_path;
3582         ref_path = NULL;
3583         spin_unlock(&cifs_tcp_ses_lock);
3584
3585         /*
3586          * After reconnecting to a different server, unique ids won't
3587          * match anymore, so we disable serverino. This prevents
3588          * dentry revalidation to think the dentry are stale (ESTALE).
3589          */
3590         cifs_autodisable_serverino(cifs_sb);
3591         /*
3592          * Force the use of prefix path to support failover on DFS paths that
3593          * resolve to targets that have different prefix paths.
3594          */
3595         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3596         kfree(cifs_sb->prepath);
3597         cifs_sb->prepath = ctx->prepath;
3598         ctx->prepath = NULL;
3599         uuid_copy(&cifs_sb->dfs_mount_id, &mount_id);
3600
3601 out:
3602         free_xid(xid);
3603         cifs_try_adding_channels(cifs_sb, ses);
3604         return mount_setup_tlink(cifs_sb, ses, tcon);
3605
3606 error:
3607         kfree(ref_path);
3608         kfree(full_path);
3609         kfree(cifs_sb->origin_fullpath);
3610         dfs_cache_put_refsrv_sessions(&mount_id);
3611         mount_put_conns(cifs_sb, xid, server, ses, tcon);
3612         return rc;
3613 }
3614 #else
3615 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3616 {
3617         int rc = 0;
3618         unsigned int xid;
3619         struct cifs_ses *ses;
3620         struct cifs_tcon *tcon;
3621         struct TCP_Server_Info *server;
3622
3623         rc = mount_get_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3624         if (rc)
3625                 goto error;
3626
3627         if (tcon) {
3628                 rc = is_path_remote(cifs_sb, ctx, xid, server, tcon);
3629                 if (rc == -EREMOTE)
3630                         rc = -EOPNOTSUPP;
3631                 if (rc)
3632                         goto error;
3633         }
3634
3635         free_xid(xid);
3636
3637         return mount_setup_tlink(cifs_sb, ses, tcon);
3638
3639 error:
3640         mount_put_conns(cifs_sb, xid, server, ses, tcon);
3641         return rc;
3642 }
3643 #endif
3644
3645 /*
3646  * Issue a TREE_CONNECT request.
3647  */
3648 int
3649 CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3650          const char *tree, struct cifs_tcon *tcon,
3651          const struct nls_table *nls_codepage)
3652 {
3653         struct smb_hdr *smb_buffer;
3654         struct smb_hdr *smb_buffer_response;
3655         TCONX_REQ *pSMB;
3656         TCONX_RSP *pSMBr;
3657         unsigned char *bcc_ptr;
3658         int rc = 0;
3659         int length;
3660         __u16 bytes_left, count;
3661
3662         if (ses == NULL)
3663                 return -EIO;
3664
3665         smb_buffer = cifs_buf_get();
3666         if (smb_buffer == NULL)
3667                 return -ENOMEM;
3668
3669         smb_buffer_response = smb_buffer;
3670
3671         header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3672                         NULL /*no tid */ , 4 /*wct */ );
3673
3674         smb_buffer->Mid = get_next_mid(ses->server);
3675         smb_buffer->Uid = ses->Suid;
3676         pSMB = (TCONX_REQ *) smb_buffer;
3677         pSMBr = (TCONX_RSP *) smb_buffer_response;
3678
3679         pSMB->AndXCommand = 0xFF;
3680         pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3681         bcc_ptr = &pSMB->Password[0];
3682         if (tcon->pipe || (ses->server->sec_mode & SECMODE_USER)) {
3683                 pSMB->PasswordLength = cpu_to_le16(1);  /* minimum */
3684                 *bcc_ptr = 0; /* password is null byte */
3685                 bcc_ptr++;              /* skip password */
3686                 /* already aligned so no need to do it below */
3687         }
3688
3689         if (ses->server->sign)
3690                 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3691
3692         if (ses->capabilities & CAP_STATUS32) {
3693                 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3694         }
3695         if (ses->capabilities & CAP_DFS) {
3696                 smb_buffer->Flags2 |= SMBFLG2_DFS;
3697         }
3698         if (ses->capabilities & CAP_UNICODE) {
3699                 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3700                 length =
3701                     cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3702                         6 /* max utf8 char length in bytes */ *
3703                         (/* server len*/ + 256 /* share len */), nls_codepage);
3704                 bcc_ptr += 2 * length;  /* convert num 16 bit words to bytes */
3705                 bcc_ptr += 2;   /* skip trailing null */
3706         } else {                /* ASCII */
3707                 strcpy(bcc_ptr, tree);
3708                 bcc_ptr += strlen(tree) + 1;
3709         }
3710         strcpy(bcc_ptr, "?????");
3711         bcc_ptr += strlen("?????");
3712         bcc_ptr += 1;
3713         count = bcc_ptr - &pSMB->Password[0];
3714         be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3715         pSMB->ByteCount = cpu_to_le16(count);
3716
3717         rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3718                          0);
3719
3720         /* above now done in SendReceive */
3721         if (rc == 0) {
3722                 bool is_unicode;
3723
3724                 tcon->tidStatus = CifsGood;
3725                 tcon->need_reconnect = false;
3726                 tcon->tid = smb_buffer_response->Tid;
3727                 bcc_ptr = pByteArea(smb_buffer_response);
3728                 bytes_left = get_bcc(smb_buffer_response);
3729                 length = strnlen(bcc_ptr, bytes_left - 2);
3730                 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3731                         is_unicode = true;
3732                 else
3733                         is_unicode = false;
3734
3735
3736                 /* skip service field (NB: this field is always ASCII) */
3737                 if (length == 3) {
3738                         if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3739                             (bcc_ptr[2] == 'C')) {
3740                                 cifs_dbg(FYI, "IPC connection\n");
3741                                 tcon->ipc = true;
3742                                 tcon->pipe = true;
3743                         }
3744                 } else if (length == 2) {
3745                         if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3746                                 /* the most common case */
3747                                 cifs_dbg(FYI, "disk share connection\n");
3748                         }
3749                 }
3750                 bcc_ptr += length + 1;
3751                 bytes_left -= (length + 1);
3752                 strlcpy(tcon->treeName, tree, sizeof(tcon->treeName));
3753
3754                 /* mostly informational -- no need to fail on error here */
3755                 kfree(tcon->nativeFileSystem);
3756                 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3757                                                       bytes_left, is_unicode,
3758                                                       nls_codepage);
3759
3760                 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3761
3762                 if ((smb_buffer_response->WordCount == 3) ||
3763                          (smb_buffer_response->WordCount == 7))
3764                         /* field is in same location */
3765                         tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3766                 else
3767                         tcon->Flags = 0;
3768                 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3769         }
3770
3771         cifs_buf_release(smb_buffer);
3772         return rc;
3773 }
3774
3775 static void delayed_free(struct rcu_head *p)
3776 {
3777         struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3778
3779         unload_nls(cifs_sb->local_nls);
3780         smb3_cleanup_fs_context(cifs_sb->ctx);
3781         kfree(cifs_sb);
3782 }
3783
3784 void
3785 cifs_umount(struct cifs_sb_info *cifs_sb)
3786 {
3787         struct rb_root *root = &cifs_sb->tlink_tree;
3788         struct rb_node *node;
3789         struct tcon_link *tlink;
3790
3791         cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3792
3793         spin_lock(&cifs_sb->tlink_tree_lock);
3794         while ((node = rb_first(root))) {
3795                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3796                 cifs_get_tlink(tlink);
3797                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3798                 rb_erase(node, root);
3799
3800                 spin_unlock(&cifs_sb->tlink_tree_lock);
3801                 cifs_put_tlink(tlink);
3802                 spin_lock(&cifs_sb->tlink_tree_lock);
3803         }
3804         spin_unlock(&cifs_sb->tlink_tree_lock);
3805
3806         kfree(cifs_sb->prepath);
3807 #ifdef CONFIG_CIFS_DFS_UPCALL
3808         dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
3809         kfree(cifs_sb->origin_fullpath);
3810 #endif
3811         call_rcu(&cifs_sb->rcu, delayed_free);
3812 }
3813
3814 int
3815 cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses)
3816 {
3817         int rc = 0;
3818         struct TCP_Server_Info *server = cifs_ses_server(ses);
3819
3820         if (!server->ops->need_neg || !server->ops->negotiate)
3821                 return -ENOSYS;
3822
3823         /* only send once per connect */
3824         if (!server->ops->need_neg(server))
3825                 return 0;
3826
3827         rc = server->ops->negotiate(xid, ses);
3828         if (rc == 0) {
3829                 spin_lock(&GlobalMid_Lock);
3830                 if (server->tcpStatus == CifsNeedNegotiate)
3831                         server->tcpStatus = CifsGood;
3832                 else
3833                         rc = -EHOSTDOWN;
3834                 spin_unlock(&GlobalMid_Lock);
3835         }
3836
3837         return rc;
3838 }
3839
3840 int
3841 cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3842                    struct nls_table *nls_info)
3843 {
3844         int rc = -ENOSYS;
3845         struct TCP_Server_Info *server = cifs_ses_server(ses);
3846
3847         if (!ses->binding) {
3848                 ses->capabilities = server->capabilities;
3849                 if (!linuxExtEnabled)
3850                         ses->capabilities &= (~server->vals->cap_unix);
3851
3852                 if (ses->auth_key.response) {
3853                         cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3854                                  ses->auth_key.response);
3855                         kfree(ses->auth_key.response);
3856                         ses->auth_key.response = NULL;
3857                         ses->auth_key.len = 0;
3858                 }
3859         }
3860
3861         cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3862                  server->sec_mode, server->capabilities, server->timeAdj);
3863
3864         if (server->ops->sess_setup)
3865                 rc = server->ops->sess_setup(xid, ses, nls_info);
3866
3867         if (rc)
3868                 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3869
3870         return rc;
3871 }
3872
3873 static int
3874 cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3875 {
3876         ctx->sectype = ses->sectype;
3877
3878         /* krb5 is special, since we don't need username or pw */
3879         if (ctx->sectype == Kerberos)
3880                 return 0;
3881
3882         return cifs_set_cifscreds(ctx, ses);
3883 }
3884
3885 static struct cifs_tcon *
3886 cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3887 {
3888         int rc;
3889         struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3890         struct cifs_ses *ses;
3891         struct cifs_tcon *tcon = NULL;
3892         struct smb3_fs_context *ctx;
3893
3894         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3895         if (ctx == NULL)
3896                 return ERR_PTR(-ENOMEM);
3897
3898         ctx->local_nls = cifs_sb->local_nls;
3899         ctx->linux_uid = fsuid;
3900         ctx->cred_uid = fsuid;
3901         ctx->UNC = master_tcon->treeName;
3902         ctx->retry = master_tcon->retry;
3903         ctx->nocase = master_tcon->nocase;
3904         ctx->nohandlecache = master_tcon->nohandlecache;
3905         ctx->local_lease = master_tcon->local_lease;
3906         ctx->no_lease = master_tcon->no_lease;
3907         ctx->resilient = master_tcon->use_resilient;
3908         ctx->persistent = master_tcon->use_persistent;
3909         ctx->handle_timeout = master_tcon->handle_timeout;
3910         ctx->no_linux_ext = !master_tcon->unix_ext;
3911         ctx->linux_ext = master_tcon->posix_extensions;
3912         ctx->sectype = master_tcon->ses->sectype;
3913         ctx->sign = master_tcon->ses->sign;
3914         ctx->seal = master_tcon->seal;
3915         ctx->witness = master_tcon->use_witness;
3916
3917         rc = cifs_set_vol_auth(ctx, master_tcon->ses);
3918         if (rc) {
3919                 tcon = ERR_PTR(rc);
3920                 goto out;
3921         }
3922
3923         /* get a reference for the same TCP session */
3924         spin_lock(&cifs_tcp_ses_lock);
3925         ++master_tcon->ses->server->srv_count;
3926         spin_unlock(&cifs_tcp_ses_lock);
3927
3928         ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
3929         if (IS_ERR(ses)) {
3930                 tcon = (struct cifs_tcon *)ses;
3931                 cifs_put_tcp_session(master_tcon->ses->server, 0);
3932                 goto out;
3933         }
3934
3935         tcon = cifs_get_tcon(ses, ctx);
3936         if (IS_ERR(tcon)) {
3937                 cifs_put_smb_ses(ses);
3938                 goto out;
3939         }
3940
3941         if (cap_unix(ses))
3942                 reset_cifs_unix_caps(0, tcon, NULL, ctx);
3943
3944 out:
3945         kfree(ctx->username);
3946         kfree_sensitive(ctx->password);
3947         kfree(ctx);
3948
3949         return tcon;
3950 }
3951
3952 struct cifs_tcon *
3953 cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
3954 {
3955         return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
3956 }
3957
3958 /* find and return a tlink with given uid */
3959 static struct tcon_link *
3960 tlink_rb_search(struct rb_root *root, kuid_t uid)
3961 {
3962         struct rb_node *node = root->rb_node;
3963         struct tcon_link *tlink;
3964
3965         while (node) {
3966                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3967
3968                 if (uid_gt(tlink->tl_uid, uid))
3969                         node = node->rb_left;
3970                 else if (uid_lt(tlink->tl_uid, uid))
3971                         node = node->rb_right;
3972                 else
3973                         return tlink;
3974         }
3975         return NULL;
3976 }
3977
3978 /* insert a tcon_link into the tree */
3979 static void
3980 tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
3981 {
3982         struct rb_node **new = &(root->rb_node), *parent = NULL;
3983         struct tcon_link *tlink;
3984
3985         while (*new) {
3986                 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
3987                 parent = *new;
3988
3989                 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
3990                         new = &((*new)->rb_left);
3991                 else
3992                         new = &((*new)->rb_right);
3993         }
3994
3995         rb_link_node(&new_tlink->tl_rbnode, parent, new);
3996         rb_insert_color(&new_tlink->tl_rbnode, root);
3997 }
3998
3999 /*
4000  * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
4001  * current task.
4002  *
4003  * If the superblock doesn't refer to a multiuser mount, then just return
4004  * the master tcon for the mount.
4005  *
4006  * First, search the rbtree for an existing tcon for this fsuid. If one
4007  * exists, then check to see if it's pending construction. If it is then wait
4008  * for construction to complete. Once it's no longer pending, check to see if
4009  * it failed and either return an error or retry construction, depending on
4010  * the timeout.
4011  *
4012  * If one doesn't exist then insert a new tcon_link struct into the tree and
4013  * try to construct a new one.
4014  */
4015 struct tcon_link *
4016 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
4017 {
4018         int ret;
4019         kuid_t fsuid = current_fsuid();
4020         struct tcon_link *tlink, *newtlink;
4021
4022         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
4023                 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
4024
4025         spin_lock(&cifs_sb->tlink_tree_lock);
4026         tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4027         if (tlink)
4028                 cifs_get_tlink(tlink);
4029         spin_unlock(&cifs_sb->tlink_tree_lock);
4030
4031         if (tlink == NULL) {
4032                 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4033                 if (newtlink == NULL)
4034                         return ERR_PTR(-ENOMEM);
4035                 newtlink->tl_uid = fsuid;
4036                 newtlink->tl_tcon = ERR_PTR(-EACCES);
4037                 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4038                 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4039                 cifs_get_tlink(newtlink);
4040
4041                 spin_lock(&cifs_sb->tlink_tree_lock);
4042                 /* was one inserted after previous search? */
4043                 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4044                 if (tlink) {
4045                         cifs_get_tlink(tlink);
4046                         spin_unlock(&cifs_sb->tlink_tree_lock);
4047                         kfree(newtlink);
4048                         goto wait_for_construction;
4049                 }
4050                 tlink = newtlink;
4051                 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4052                 spin_unlock(&cifs_sb->tlink_tree_lock);
4053         } else {
4054 wait_for_construction:
4055                 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4056                                   TASK_INTERRUPTIBLE);
4057                 if (ret) {
4058                         cifs_put_tlink(tlink);
4059                         return ERR_PTR(-ERESTARTSYS);
4060                 }
4061
4062                 /* if it's good, return it */
4063                 if (!IS_ERR(tlink->tl_tcon))
4064                         return tlink;
4065
4066                 /* return error if we tried this already recently */
4067                 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4068                         cifs_put_tlink(tlink);
4069                         return ERR_PTR(-EACCES);
4070                 }
4071
4072                 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4073                         goto wait_for_construction;
4074         }
4075
4076         tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4077         clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4078         wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4079
4080         if (IS_ERR(tlink->tl_tcon)) {
4081                 cifs_put_tlink(tlink);
4082                 return ERR_PTR(-EACCES);
4083         }
4084
4085         return tlink;
4086 }
4087
4088 /*
4089  * periodic workqueue job that scans tcon_tree for a superblock and closes
4090  * out tcons.
4091  */
4092 static void
4093 cifs_prune_tlinks(struct work_struct *work)
4094 {
4095         struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4096                                                     prune_tlinks.work);
4097         struct rb_root *root = &cifs_sb->tlink_tree;
4098         struct rb_node *node;
4099         struct rb_node *tmp;
4100         struct tcon_link *tlink;
4101
4102         /*
4103          * Because we drop the spinlock in the loop in order to put the tlink
4104          * it's not guarded against removal of links from the tree. The only
4105          * places that remove entries from the tree are this function and
4106          * umounts. Because this function is non-reentrant and is canceled
4107          * before umount can proceed, this is safe.
4108          */
4109         spin_lock(&cifs_sb->tlink_tree_lock);
4110         node = rb_first(root);
4111         while (node != NULL) {
4112                 tmp = node;
4113                 node = rb_next(tmp);
4114                 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4115
4116                 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4117                     atomic_read(&tlink->tl_count) != 0 ||
4118                     time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4119                         continue;
4120
4121                 cifs_get_tlink(tlink);
4122                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4123                 rb_erase(tmp, root);
4124
4125                 spin_unlock(&cifs_sb->tlink_tree_lock);
4126                 cifs_put_tlink(tlink);
4127                 spin_lock(&cifs_sb->tlink_tree_lock);
4128         }
4129         spin_unlock(&cifs_sb->tlink_tree_lock);
4130
4131         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4132                                 TLINK_IDLE_EXPIRE);
4133 }
4134
4135 #ifdef CONFIG_CIFS_DFS_UPCALL
4136 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4137 {
4138         int rc;
4139         struct TCP_Server_Info *server = tcon->ses->server;
4140         const struct smb_version_operations *ops = server->ops;
4141         struct dfs_cache_tgt_list tl;
4142         struct dfs_cache_tgt_iterator *it = NULL;
4143         char *tree;
4144         const char *tcp_host;
4145         size_t tcp_host_len;
4146         const char *dfs_host;
4147         size_t dfs_host_len;
4148         char *share = NULL, *prefix = NULL;
4149         struct dfs_info3_param ref = {0};
4150         bool isroot;
4151
4152         tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL);
4153         if (!tree)
4154                 return -ENOMEM;
4155
4156         /* If it is not dfs or there was no cached dfs referral, then reconnect to same share */
4157         if (!tcon->dfs_path || dfs_cache_noreq_find(tcon->dfs_path + 1, &ref, &tl)) {
4158                 if (tcon->ipc) {
4159                         scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
4160                         rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
4161                 } else {
4162                         rc = ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
4163                 }
4164                 goto out;
4165         }
4166
4167         isroot = ref.server_type == DFS_TYPE_ROOT;
4168         free_dfs_info_param(&ref);
4169
4170         extract_unc_hostname(server->hostname, &tcp_host, &tcp_host_len);
4171
4172         for (it = dfs_cache_get_tgt_iterator(&tl); it; it = dfs_cache_get_next_tgt(&tl, it)) {
4173                 bool target_match;
4174
4175                 kfree(share);
4176                 kfree(prefix);
4177                 share = NULL;
4178                 prefix = NULL;
4179
4180                 rc = dfs_cache_get_tgt_share(tcon->dfs_path + 1, it, &share, &prefix);
4181                 if (rc) {
4182                         cifs_dbg(VFS, "%s: failed to parse target share %d\n",
4183                                  __func__, rc);
4184                         continue;
4185                 }
4186
4187                 extract_unc_hostname(share, &dfs_host, &dfs_host_len);
4188
4189                 if (dfs_host_len != tcp_host_len
4190                     || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) {
4191                         cifs_dbg(FYI, "%s: %.*s doesn't match %.*s\n", __func__, (int)dfs_host_len,
4192                                  dfs_host, (int)tcp_host_len, tcp_host);
4193
4194                         rc = match_target_ip(server, dfs_host, dfs_host_len, &target_match);
4195                         if (rc) {
4196                                 cifs_dbg(VFS, "%s: failed to match target ip: %d\n", __func__, rc);
4197                                 break;
4198                         }
4199
4200                         if (!target_match) {
4201                                 cifs_dbg(FYI, "%s: skipping target\n", __func__);
4202                                 continue;
4203                         }
4204                 }
4205
4206                 if (tcon->ipc) {
4207                         scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", share);
4208                         rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
4209                 } else {
4210                         scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);
4211                         rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
4212                         /* Only handle prefix paths of DFS link targets */
4213                         if (!rc && !isroot) {
4214                                 rc = update_super_prepath(tcon, prefix);
4215                                 break;
4216                         }
4217                 }
4218                 if (rc == -EREMOTE)
4219                         break;
4220         }
4221
4222         kfree(share);
4223         kfree(prefix);
4224
4225         if (!rc) {
4226                 if (it)
4227                         rc = dfs_cache_noreq_update_tgthint(tcon->dfs_path + 1, it);
4228                 else
4229                         rc = -ENOENT;
4230         }
4231         dfs_cache_free_tgts(&tl);
4232 out:
4233         kfree(tree);
4234         return rc;
4235 }
4236 #else
4237 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4238 {
4239         const struct smb_version_operations *ops = tcon->ses->server->ops;
4240
4241         return ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
4242 }
4243 #endif