fs/cifs/cifs_debug.c

   1 /*
   2  *   fs/cifs_debug.c
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2000,2005
   5  *
   6  *   Modified by Steve French (sfrench@us.ibm.com)
   7  *
   8  *   This program is free software;  you can redistribute it and/or modify
   9  *   it under the terms of the GNU General Public License as published by
  10  *   the Free Software Foundation; either version 2 of the License, or
  11  *   (at your option) any later version.
  12  *
  13  *   This program is distributed in the hope that it will be useful,
  14  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  16  *   the GNU General Public License for more details.
  17  *
  18  *   You should have received a copy of the GNU General Public License
  19  *   along with this program;  if not, write to the Free Software
  20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  21  */
  22 #include <linux/fs.h>
  23 #include <linux/string.h>
  24 #include <linux/ctype.h>
  25 #include <linux/module.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/uaccess.h>
  28 #include "cifspdu.h"
  29 #include "cifsglob.h"
  30 #include "cifsproto.h"
  31 #include "cifs_debug.h"
  32 #include "cifsfs.h"
  33
  34 void
  35 cifs_dump_mem(char *label, void *data, int length)
  36 {
  37         pr_debug("%s: dump of %d bytes of data at 0x%p\n", label, length, data);
  38         print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET, 16, 4,
  39                        data, length, true);
  40 }
  41
  42 #ifdef CONFIG_CIFS_DEBUG
  43 void cifs_vfs_err(const char *fmt, ...)
  44 {
  45         struct va_format vaf;
  46         va_list args;
  47
  48         va_start(args, fmt);
  49
  50         vaf.fmt = fmt;
  51         vaf.va = &args;
  52
  53         pr_err_ratelimited("CIFS VFS: %pV", &vaf);
  54
  55         va_end(args);
  56 }
  57 #endif
  58
  59 void cifs_dump_detail(void *buf)
  60 {
  61 #ifdef CONFIG_CIFS_DEBUG2
  62         struct smb_hdr *smb = (struct smb_hdr *)buf;
  63
  64         cifs_dbg(VFS, "Cmd: %d Err: 0x%x Flags: 0x%x Flgs2: 0x%x Mid: %d Pid: %d\n",
  65                  smb->Command, smb->Status.CifsError,
  66                  smb->Flags, smb->Flags2, smb->Mid, smb->Pid);
  67         cifs_dbg(VFS, "smb buf %p len %u\n", smb, smbCalcSize(smb));
  68 #endif /* CONFIG_CIFS_DEBUG2 */
  69 }
  70
  71 void cifs_dump_mids(struct TCP_Server_Info *server)
  72 {
  73 #ifdef CONFIG_CIFS_DEBUG2
  74         struct list_head *tmp;
  75         struct mid_q_entry *mid_entry;
  76
  77         if (server == NULL)
  78                 return;
  79
  80         cifs_dbg(VFS, "Dump pending requests:\n");
  81         spin_lock(&GlobalMid_Lock);
  82         list_for_each(tmp, &server->pending_mid_q) {
  83                 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
  84                 cifs_dbg(VFS, "State: %d Cmd: %d Pid: %d Cbdata: %p Mid %llu\n",
  85                          mid_entry->mid_state,
  86                          le16_to_cpu(mid_entry->command),
  87                          mid_entry->pid,
  88                          mid_entry->callback_data,
  89                          mid_entry->mid);
  90 #ifdef CONFIG_CIFS_STATS2
  91                 cifs_dbg(VFS, "IsLarge: %d buf: %p time rcv: %ld now: %ld\n",
  92                          mid_entry->large_buf,
  93                          mid_entry->resp_buf,
  94                          mid_entry->when_received,
  95                          jiffies);
  96 #endif /* STATS2 */
  97                 cifs_dbg(VFS, "IsMult: %d IsEnd: %d\n",
  98                          mid_entry->multiRsp, mid_entry->multiEnd);
  99                 if (mid_entry->resp_buf) {
 100                         cifs_dump_detail(mid_entry->resp_buf);
 101                         cifs_dump_mem("existing buf: ",
 102                                 mid_entry->resp_buf, 62);
 103                 }
 104         }
 105         spin_unlock(&GlobalMid_Lock);
 106 #endif /* CONFIG_CIFS_DEBUG2 */
 107 }
 108
 109 #ifdef CONFIG_PROC_FS
 110 static int cifs_debug_data_proc_show(struct seq_file *m, void *v)
 111 {
 112         struct list_head *tmp1, *tmp2, *tmp3;
 113         struct mid_q_entry *mid_entry;
 114         struct TCP_Server_Info *server;
 115         struct cifs_ses *ses;
 116         struct cifs_tcon *tcon;
 117         int i, j;
 118         __u32 dev_type;
 119
 120         seq_puts(m,
 121                     "Display Internal CIFS Data Structures for Debugging\n"
 122                     "---------------------------------------------------\n");
 123         seq_printf(m, "CIFS Version %s\n", CIFS_VERSION);
 124         seq_printf(m, "Features:");
 125 #ifdef CONFIG_CIFS_DFS_UPCALL
 126         seq_printf(m, " dfs");
 127 #endif
 128 #ifdef CONFIG_CIFS_FSCACHE
 129         seq_printf(m, " fscache");
 130 #endif
 131 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 132         seq_printf(m, " lanman");
 133 #endif
 134 #ifdef CONFIG_CIFS_POSIX
 135         seq_printf(m, " posix");
 136 #endif
 137 #ifdef CONFIG_CIFS_UPCALL
 138         seq_printf(m, " spnego");
 139 #endif
 140 #ifdef CONFIG_CIFS_XATTR
 141         seq_printf(m, " xattr");
 142 #endif
 143 #ifdef CONFIG_CIFS_ACL
 144         seq_printf(m, " acl");
 145 #endif
 146         seq_putc(m, '\n');
 147         seq_printf(m, "Active VFS Requests: %d\n", GlobalTotalActiveXid);
 148         seq_printf(m, "Servers:");
 149
 150         i = 0;
 151         spin_lock(&cifs_tcp_ses_lock);
 152         list_for_each(tmp1, &cifs_tcp_ses_list) {
 153                 server = list_entry(tmp1, struct TCP_Server_Info,
 154                                     tcp_ses_list);
 155                 seq_printf(m, "\nNumber of credits: %d", server->credits);
 156                 i++;
 157                 list_for_each(tmp2, &server->smb_ses_list) {
 158                         ses = list_entry(tmp2, struct cifs_ses,
 159                                          smb_ses_list);
 160                         if ((ses->serverDomain == NULL) ||
 161                                 (ses->serverOS == NULL) ||
 162                                 (ses->serverNOS == NULL)) {
 163                                 seq_printf(m, "\n%d) Name: %s Uses: %d Capability: 0x%x\tSession Status: %d\t",
 164                                         i, ses->serverName, ses->ses_count,
 165                                         ses->capabilities, ses->status);
 166                                 if (ses->session_flags & SMB2_SESSION_FLAG_IS_GUEST)
 167                                         seq_printf(m, "Guest\t");
 168                                 else if (ses->session_flags & SMB2_SESSION_FLAG_IS_NULL)
 169                                         seq_printf(m, "Anonymous\t");
 170                         } else {
 171                                 seq_printf(m,
 172                                     "\n%d) Name: %s  Domain: %s Uses: %d OS:"
 173                                     " %s\n\tNOS: %s\tCapability: 0x%x\n\tSMB"
 174                                     " session status: %d\t",
 175                                 i, ses->serverName, ses->serverDomain,
 176                                 ses->ses_count, ses->serverOS, ses->serverNOS,
 177                                 ses->capabilities, ses->status);
 178                         }
 179                         seq_printf(m, "TCP status: %d\n\tLocal Users To "
 180                                    "Server: %d SecMode: 0x%x Req On Wire: %d",
 181                                    server->tcpStatus, server->srv_count,
 182                                    server->sec_mode, in_flight(server));
 183
 184 #ifdef CONFIG_CIFS_STATS2
 185                         seq_printf(m, " In Send: %d In MaxReq Wait: %d",
 186                                 atomic_read(&server->in_send),
 187                                 atomic_read(&server->num_waiters));
 188 #endif
 189
 190                         seq_puts(m, "\n\tShares:");
 191                         j = 0;
 192                         list_for_each(tmp3, &ses->tcon_list) {
 193                                 tcon = list_entry(tmp3, struct cifs_tcon,
 194                                                   tcon_list);
 195                                 ++j;
 196                                 dev_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
 197                                 seq_printf(m, "\n\t%d) %s Mounts: %d ", j,
 198                                            tcon->treeName, tcon->tc_count);
 199                                 if (tcon->nativeFileSystem) {
 200                                         seq_printf(m, "Type: %s ",
 201                                                    tcon->nativeFileSystem);
 202                                 }
 203                                 seq_printf(m, "DevInfo: 0x%x Attributes: 0x%x"
 204                                         "\n\tPathComponentMax: %d Status: %d",
 205                                         le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics),
 206                                         le32_to_cpu(tcon->fsAttrInfo.Attributes),
 207                                         le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength),
 208                                         tcon->tidStatus);
 209                                 if (dev_type == FILE_DEVICE_DISK)
 210                                         seq_puts(m, " type: DISK ");
 211                                 else if (dev_type == FILE_DEVICE_CD_ROM)
 212                                         seq_puts(m, " type: CDROM ");
 213                                 else
 214                                         seq_printf(m, " type: %d ", dev_type);
 215                                 if (server->ops->dump_share_caps)
 216                                         server->ops->dump_share_caps(m, tcon);
 217
 218                                 if (tcon->need_reconnect)
 219                                         seq_puts(m, "\tDISCONNECTED ");
 220                                 seq_putc(m, '\n');
 221                         }
 222
 223                         seq_puts(m, "\n\tMIDs:\n");
 224
 225                         spin_lock(&GlobalMid_Lock);
 226                         list_for_each(tmp3, &server->pending_mid_q) {
 227                                 mid_entry = list_entry(tmp3, struct mid_q_entry,
 228                                         qhead);
 229                                 seq_printf(m, "\tState: %d com: %d pid:"
 230                                               " %d cbdata: %p mid %llu\n",
 231                                               mid_entry->mid_state,
 232                                               le16_to_cpu(mid_entry->command),
 233                                               mid_entry->pid,
 234                                               mid_entry->callback_data,
 235                                               mid_entry->mid);
 236                         }
 237                         spin_unlock(&GlobalMid_Lock);
 238                 }
 239         }
 240         spin_unlock(&cifs_tcp_ses_lock);
 241         seq_putc(m, '\n');
 242
 243         /* BB add code to dump additional info such as TCP session info now */
 244         return 0;
 245 }
 246
 247 static int cifs_debug_data_proc_open(struct inode *inode, struct file *file)
 248 {
 249         return single_open(file, cifs_debug_data_proc_show, NULL);
 250 }
 251
 252 static const struct file_operations cifs_debug_data_proc_fops = {
 253         .open           = cifs_debug_data_proc_open,
 254         .read           = seq_read,
 255         .llseek         = seq_lseek,
 256         .release        = single_release,
 257 };
 258
 259 #ifdef CONFIG_CIFS_STATS
 260 static ssize_t cifs_stats_proc_write(struct file *file,
 261                 const char __user *buffer, size_t count, loff_t *ppos)
 262 {
 263         bool bv;
 264         int rc;
 265         struct list_head *tmp1, *tmp2, *tmp3;
 266         struct TCP_Server_Info *server;
 267         struct cifs_ses *ses;
 268         struct cifs_tcon *tcon;
 269
 270         rc = kstrtobool_from_user(buffer, count, &bv);
 271         if (rc == 0) {
 272 #ifdef CONFIG_CIFS_STATS2
 273                 atomic_set(&totBufAllocCount, 0);
 274                 atomic_set(&totSmBufAllocCount, 0);
 275 #endif /* CONFIG_CIFS_STATS2 */
 276                 spin_lock(&cifs_tcp_ses_lock);
 277                 list_for_each(tmp1, &cifs_tcp_ses_list) {
 278                         server = list_entry(tmp1, struct TCP_Server_Info,
 279                                             tcp_ses_list);
 280                         list_for_each(tmp2, &server->smb_ses_list) {
 281                                 ses = list_entry(tmp2, struct cifs_ses,
 282                                                  smb_ses_list);
 283                                 list_for_each(tmp3, &ses->tcon_list) {
 284                                         tcon = list_entry(tmp3,
 285                                                           struct cifs_tcon,
 286                                                           tcon_list);
 287                                         atomic_set(&tcon->num_smbs_sent, 0);
 288                                         if (server->ops->clear_stats)
 289                                                 server->ops->clear_stats(tcon);
 290                                 }
 291                         }
 292                 }
 293                 spin_unlock(&cifs_tcp_ses_lock);
 294         } else {
 295                 return rc;
 296         }
 297
 298         return count;
 299 }
 300
 301 static int cifs_stats_proc_show(struct seq_file *m, void *v)
 302 {
 303         int i;
 304         struct list_head *tmp1, *tmp2, *tmp3;
 305         struct TCP_Server_Info *server;
 306         struct cifs_ses *ses;
 307         struct cifs_tcon *tcon;
 308
 309         seq_printf(m,
 310                         "Resources in use\nCIFS Session: %d\n",
 311                         sesInfoAllocCount.counter);
 312         seq_printf(m, "Share (unique mount targets): %d\n",
 313                         tconInfoAllocCount.counter);
 314         seq_printf(m, "SMB Request/Response Buffer: %d Pool size: %d\n",
 315                         bufAllocCount.counter,
 316                         cifs_min_rcv + tcpSesAllocCount.counter);
 317         seq_printf(m, "SMB Small Req/Resp Buffer: %d Pool size: %d\n",
 318                         smBufAllocCount.counter, cifs_min_small);
 319 #ifdef CONFIG_CIFS_STATS2
 320         seq_printf(m, "Total Large %d Small %d Allocations\n",
 321                                 atomic_read(&totBufAllocCount),
 322                                 atomic_read(&totSmBufAllocCount));
 323 #endif /* CONFIG_CIFS_STATS2 */
 324
 325         seq_printf(m, "Operations (MIDs): %d\n", atomic_read(&midCount));
 326         seq_printf(m,
 327                 "\n%d session %d share reconnects\n",
 328                 tcpSesReconnectCount.counter, tconInfoReconnectCount.counter);
 329
 330         seq_printf(m,
 331                 "Total vfs operations: %d maximum at one time: %d\n",
 332                 GlobalCurrentXid, GlobalMaxActiveXid);
 333
 334         i = 0;
 335         spin_lock(&cifs_tcp_ses_lock);
 336         list_for_each(tmp1, &cifs_tcp_ses_list) {
 337                 server = list_entry(tmp1, struct TCP_Server_Info,
 338                                     tcp_ses_list);
 339                 list_for_each(tmp2, &server->smb_ses_list) {
 340                         ses = list_entry(tmp2, struct cifs_ses,
 341                                          smb_ses_list);
 342                         list_for_each(tmp3, &ses->tcon_list) {
 343                                 tcon = list_entry(tmp3,
 344                                                   struct cifs_tcon,
 345                                                   tcon_list);
 346                                 i++;
 347                                 seq_printf(m, "\n%d) %s", i, tcon->treeName);
 348                                 if (tcon->need_reconnect)
 349                                         seq_puts(m, "\tDISCONNECTED ");
 350                                 seq_printf(m, "\nSMBs: %d",
 351                                            atomic_read(&tcon->num_smbs_sent));
 352                                 if (server->ops->print_stats)
 353                                         server->ops->print_stats(m, tcon);
 354                         }
 355                 }
 356         }
 357         spin_unlock(&cifs_tcp_ses_lock);
 358
 359         seq_putc(m, '\n');
 360         return 0;
 361 }
 362
 363 static int cifs_stats_proc_open(struct inode *inode, struct file *file)
 364 {
 365         return single_open(file, cifs_stats_proc_show, NULL);
 366 }
 367
 368 static const struct file_operations cifs_stats_proc_fops = {
 369         .open           = cifs_stats_proc_open,
 370         .read           = seq_read,
 371         .llseek         = seq_lseek,
 372         .release        = single_release,
 373         .write          = cifs_stats_proc_write,
 374 };
 375 #endif /* STATS */
 376
 377 static struct proc_dir_entry *proc_fs_cifs;
 378 static const struct file_operations cifsFYI_proc_fops;
 379 static const struct file_operations cifs_lookup_cache_proc_fops;
 380 static const struct file_operations traceSMB_proc_fops;
 381 static const struct file_operations cifs_security_flags_proc_fops;
 382 static const struct file_operations cifs_linux_ext_proc_fops;
 383
 384 void
 385 cifs_proc_init(void)
 386 {
 387         proc_fs_cifs = proc_mkdir("fs/cifs", NULL);
 388         if (proc_fs_cifs == NULL)
 389                 return;
 390
 391         proc_create("DebugData", 0, proc_fs_cifs, &cifs_debug_data_proc_fops);
 392
 393 #ifdef CONFIG_CIFS_STATS
 394         proc_create("Stats", 0, proc_fs_cifs, &cifs_stats_proc_fops);
 395 #endif /* STATS */
 396         proc_create("cifsFYI", 0, proc_fs_cifs, &cifsFYI_proc_fops);
 397         proc_create("traceSMB", 0, proc_fs_cifs, &traceSMB_proc_fops);
 398         proc_create("LinuxExtensionsEnabled", 0, proc_fs_cifs,
 399                     &cifs_linux_ext_proc_fops);
 400         proc_create("SecurityFlags", 0, proc_fs_cifs,
 401                     &cifs_security_flags_proc_fops);
 402         proc_create("LookupCacheEnabled", 0, proc_fs_cifs,
 403                     &cifs_lookup_cache_proc_fops);
 404 }
 405
 406 void
 407 cifs_proc_clean(void)
 408 {
 409         if (proc_fs_cifs == NULL)
 410                 return;
 411
 412         remove_proc_entry("DebugData", proc_fs_cifs);
 413         remove_proc_entry("cifsFYI", proc_fs_cifs);
 414         remove_proc_entry("traceSMB", proc_fs_cifs);
 415 #ifdef CONFIG_CIFS_STATS
 416         remove_proc_entry("Stats", proc_fs_cifs);
 417 #endif
 418         remove_proc_entry("SecurityFlags", proc_fs_cifs);
 419         remove_proc_entry("LinuxExtensionsEnabled", proc_fs_cifs);
 420         remove_proc_entry("LookupCacheEnabled", proc_fs_cifs);
 421         remove_proc_entry("fs/cifs", NULL);
 422 }
 423
 424 static int cifsFYI_proc_show(struct seq_file *m, void *v)
 425 {
 426         seq_printf(m, "%d\n", cifsFYI);
 427         return 0;
 428 }
 429
 430 static int cifsFYI_proc_open(struct inode *inode, struct file *file)
 431 {
 432         return single_open(file, cifsFYI_proc_show, NULL);
 433 }
 434
 435 static ssize_t cifsFYI_proc_write(struct file *file, const char __user *buffer,
 436                 size_t count, loff_t *ppos)
 437 {
 438         char c[2] = { '\0' };
 439         bool bv;
 440         int rc;
 441
 442         rc = get_user(c[0], buffer);
 443         if (rc)
 444                 return rc;
 445         if (strtobool(c, &bv) == 0)
 446                 cifsFYI = bv;
 447         else if ((c[0] > '1') && (c[0] <= '9'))
 448                 cifsFYI = (int) (c[0] - '0'); /* see cifs_debug.h for meanings */
 449
 450         return count;
 451 }
 452
 453 static const struct file_operations cifsFYI_proc_fops = {
 454         .open           = cifsFYI_proc_open,
 455         .read           = seq_read,
 456         .llseek         = seq_lseek,
 457         .release        = single_release,
 458         .write          = cifsFYI_proc_write,
 459 };
 460
 461 static int cifs_linux_ext_proc_show(struct seq_file *m, void *v)
 462 {
 463         seq_printf(m, "%d\n", linuxExtEnabled);
 464         return 0;
 465 }
 466
 467 static int cifs_linux_ext_proc_open(struct inode *inode, struct file *file)
 468 {
 469         return single_open(file, cifs_linux_ext_proc_show, NULL);
 470 }
 471
 472 static ssize_t cifs_linux_ext_proc_write(struct file *file,
 473                 const char __user *buffer, size_t count, loff_t *ppos)
 474 {
 475         int rc;
 476
 477         rc = kstrtobool_from_user(buffer, count, &linuxExtEnabled);
 478         if (rc)
 479                 return rc;
 480
 481         return count;
 482 }
 483
 484 static const struct file_operations cifs_linux_ext_proc_fops = {
 485         .open           = cifs_linux_ext_proc_open,
 486         .read           = seq_read,
 487         .llseek         = seq_lseek,
 488         .release        = single_release,
 489         .write          = cifs_linux_ext_proc_write,
 490 };
 491
 492 static int cifs_lookup_cache_proc_show(struct seq_file *m, void *v)
 493 {
 494         seq_printf(m, "%d\n", lookupCacheEnabled);
 495         return 0;
 496 }
 497
 498 static int cifs_lookup_cache_proc_open(struct inode *inode, struct file *file)
 499 {
 500         return single_open(file, cifs_lookup_cache_proc_show, NULL);
 501 }
 502
 503 static ssize_t cifs_lookup_cache_proc_write(struct file *file,
 504                 const char __user *buffer, size_t count, loff_t *ppos)
 505 {
 506         int rc;
 507
 508         rc = kstrtobool_from_user(buffer, count, &lookupCacheEnabled);
 509         if (rc)
 510                 return rc;
 511
 512         return count;
 513 }
 514
 515 static const struct file_operations cifs_lookup_cache_proc_fops = {
 516         .open           = cifs_lookup_cache_proc_open,
 517         .read           = seq_read,
 518         .llseek         = seq_lseek,
 519         .release        = single_release,
 520         .write          = cifs_lookup_cache_proc_write,
 521 };
 522
 523 static int traceSMB_proc_show(struct seq_file *m, void *v)
 524 {
 525         seq_printf(m, "%d\n", traceSMB);
 526         return 0;
 527 }
 528
 529 static int traceSMB_proc_open(struct inode *inode, struct file *file)
 530 {
 531         return single_open(file, traceSMB_proc_show, NULL);
 532 }
 533
 534 static ssize_t traceSMB_proc_write(struct file *file, const char __user *buffer,
 535                 size_t count, loff_t *ppos)
 536 {
 537         int rc;
 538
 539         rc = kstrtobool_from_user(buffer, count, &traceSMB);
 540         if (rc)
 541                 return rc;
 542
 543         return count;
 544 }
 545
 546 static const struct file_operations traceSMB_proc_fops = {
 547         .open           = traceSMB_proc_open,
 548         .read           = seq_read,
 549         .llseek         = seq_lseek,
 550         .release        = single_release,
 551         .write          = traceSMB_proc_write,
 552 };
 553
 554 static int cifs_security_flags_proc_show(struct seq_file *m, void *v)
 555 {
 556         seq_printf(m, "0x%x\n", global_secflags);
 557         return 0;
 558 }
 559
 560 static int cifs_security_flags_proc_open(struct inode *inode, struct file *file)
 561 {
 562         return single_open(file, cifs_security_flags_proc_show, NULL);
 563 }
 564
 565 /*
 566  * Ensure that if someone sets a MUST flag, that we disable all other MAY
 567  * flags except for the ones corresponding to the given MUST flag. If there are
 568  * multiple MUST flags, then try to prefer more secure ones.
 569  */
 570 static void
 571 cifs_security_flags_handle_must_flags(unsigned int *flags)
 572 {
 573         unsigned int signflags = *flags & CIFSSEC_MUST_SIGN;
 574
 575         if ((*flags & CIFSSEC_MUST_KRB5) == CIFSSEC_MUST_KRB5)
 576                 *flags = CIFSSEC_MUST_KRB5;
 577         else if ((*flags & CIFSSEC_MUST_NTLMSSP) == CIFSSEC_MUST_NTLMSSP)
 578                 *flags = CIFSSEC_MUST_NTLMSSP;
 579         else if ((*flags & CIFSSEC_MUST_NTLMV2) == CIFSSEC_MUST_NTLMV2)
 580                 *flags = CIFSSEC_MUST_NTLMV2;
 581         else if ((*flags & CIFSSEC_MUST_NTLM) == CIFSSEC_MUST_NTLM)
 582                 *flags = CIFSSEC_MUST_NTLM;
 583         else if (CIFSSEC_MUST_LANMAN &&
 584                  (*flags & CIFSSEC_MUST_LANMAN) == CIFSSEC_MUST_LANMAN)
 585                 *flags = CIFSSEC_MUST_LANMAN;
 586         else if (CIFSSEC_MUST_PLNTXT &&
 587                  (*flags & CIFSSEC_MUST_PLNTXT) == CIFSSEC_MUST_PLNTXT)
 588                 *flags = CIFSSEC_MUST_PLNTXT;
 589
 590         *flags |= signflags;
 591 }
 592
 593 static ssize_t cifs_security_flags_proc_write(struct file *file,
 594                 const char __user *buffer, size_t count, loff_t *ppos)
 595 {
 596         int rc;
 597         unsigned int flags;
 598         char flags_string[12];
 599         bool bv;
 600
 601         if ((count < 1) || (count > 11))
 602                 return -EINVAL;
 603
 604         memset(flags_string, 0, 12);
 605
 606         if (copy_from_user(flags_string, buffer, count))
 607                 return -EFAULT;
 608
 609         if (count < 3) {
 610                 /* single char or single char followed by null */
 611                 if (strtobool(flags_string, &bv) == 0) {
 612                         global_secflags = bv ? CIFSSEC_MAX : CIFSSEC_DEF;
 613                         return count;
 614                 } else if (!isdigit(flags_string[0])) {
 615                         cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 616                                         flags_string);
 617                         return -EINVAL;
 618                 }
 619         }
 620
 621         /* else we have a number */
 622         rc = kstrtouint(flags_string, 0, &flags);
 623         if (rc) {
 624                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 625                                 flags_string);
 626                 return rc;
 627         }
 628
 629         cifs_dbg(FYI, "sec flags 0x%x\n", flags);
 630
 631         if (flags == 0)  {
 632                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", flags_string);
 633                 return -EINVAL;
 634         }
 635
 636         if (flags & ~CIFSSEC_MASK) {
 637                 cifs_dbg(VFS, "Unsupported security flags: 0x%x\n",
 638                          flags & ~CIFSSEC_MASK);
 639                 return -EINVAL;
 640         }
 641
 642         cifs_security_flags_handle_must_flags(&flags);
 643
 644         /* flags look ok - update the global security flags for cifs module */
 645         global_secflags = flags;
 646         if (global_secflags & CIFSSEC_MUST_SIGN) {
 647                 /* requiring signing implies signing is allowed */
 648                 global_secflags |= CIFSSEC_MAY_SIGN;
 649                 cifs_dbg(FYI, "packet signing now required\n");
 650         } else if ((global_secflags & CIFSSEC_MAY_SIGN) == 0) {
 651                 cifs_dbg(FYI, "packet signing disabled\n");
 652         }
 653         /* BB should we turn on MAY flags for other MUST options? */
 654         return count;
 655 }
 656
 657 static const struct file_operations cifs_security_flags_proc_fops = {
 658         .open           = cifs_security_flags_proc_open,
 659         .read           = seq_read,
 660         .llseek         = seq_lseek,
 661         .release        = single_release,
 662         .write          = cifs_security_flags_proc_write,
 663 };
 664 #else
 665 inline void cifs_proc_init(void)
 666 {
 667 }
 668
 669 inline void cifs_proc_clean(void)
 670 {
 671 }
 672 #endif /* PROC_FS */