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 <asm/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_SMB_DIRECT
 132         seq_printf(m, ",SMB_DIRECT");
 133 #endif
 134 #ifdef CONFIG_CIFS_STATS2
 135         seq_printf(m, ",STATS2");
 136 #elif defined(CONFIG_CIFS_STATS)
 137         seq_printf(m, ",STATS");
 138 #endif
 139 #ifdef CONFIG_CIFS_DEBUG2
 140         seq_printf(m, ",DEBUG2");
 141 #elif defined(CONFIG_CIFS_DEBUG)
 142         seq_printf(m, ",DEBUG");
 143 #endif
 144 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 145         seq_printf(m, ",ALLOW_INSECURE_LEGACY");
 146 #endif
 147 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 148         seq_printf(m, ",WEAK_PW_HASH");
 149 #endif
 150 #ifdef CONFIG_CIFS_POSIX
 151         seq_printf(m, ",CIFS_POSIX");
 152 #endif
 153 #ifdef CONFIG_CIFS_UPCALL
 154         seq_printf(m, ",UPCALL(SPNEGO)");
 155 #endif
 156 #ifdef CONFIG_CIFS_XATTR
 157         seq_printf(m, ",XATTR");
 158 #endif
 159 #ifdef CONFIG_CIFS_ACL
 160         seq_printf(m, ",ACL");
 161 #endif
 162         seq_putc(m, '\n');
 163         seq_printf(m, "Active VFS Requests: %d\n", GlobalTotalActiveXid);
 164         seq_printf(m, "Servers:");
 165
 166         i = 0;
 167         spin_lock(&cifs_tcp_ses_lock);
 168         list_for_each(tmp1, &cifs_tcp_ses_list) {
 169                 server = list_entry(tmp1, struct TCP_Server_Info,
 170                                     tcp_ses_list);
 171                 seq_printf(m, "\nNumber of credits: %d", server->credits);
 172                 i++;
 173                 list_for_each(tmp2, &server->smb_ses_list) {
 174                         ses = list_entry(tmp2, struct cifs_ses,
 175                                          smb_ses_list);
 176                         if ((ses->serverDomain == NULL) ||
 177                                 (ses->serverOS == NULL) ||
 178                                 (ses->serverNOS == NULL)) {
 179                                 seq_printf(m, "\n%d) entry for %s not fully "
 180                                            "displayed\n\t", i, ses->serverName);
 181                         } else {
 182                                 seq_printf(m,
 183                                     "\n%d) Name: %s  Domain: %s Uses: %d OS:"
 184                                     " %s\n\tNOS: %s\tCapability: 0x%x\n\tSMB"
 185                                     " session status: %d\t",
 186                                 i, ses->serverName, ses->serverDomain,
 187                                 ses->ses_count, ses->serverOS, ses->serverNOS,
 188                                 ses->capabilities, ses->status);
 189                         }
 190                         seq_printf(m, "TCP status: %d\n\tLocal Users To "
 191                                    "Server: %d SecMode: 0x%x Req On Wire: %d",
 192                                    server->tcpStatus, server->srv_count,
 193                                    server->sec_mode, in_flight(server));
 194
 195 #ifdef CONFIG_CIFS_STATS2
 196                         seq_printf(m, " In Send: %d In MaxReq Wait: %d",
 197                                 atomic_read(&server->in_send),
 198                                 atomic_read(&server->num_waiters));
 199 #endif
 200
 201                         seq_puts(m, "\n\tShares:");
 202                         j = 0;
 203                         list_for_each(tmp3, &ses->tcon_list) {
 204                                 tcon = list_entry(tmp3, struct cifs_tcon,
 205                                                   tcon_list);
 206                                 ++j;
 207                                 dev_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
 208                                 seq_printf(m, "\n\t%d) %s Mounts: %d ", j,
 209                                            tcon->treeName, tcon->tc_count);
 210                                 if (tcon->nativeFileSystem) {
 211                                         seq_printf(m, "Type: %s ",
 212                                                    tcon->nativeFileSystem);
 213                                 }
 214                                 seq_printf(m, "DevInfo: 0x%x Attributes: 0x%x"
 215                                         "\n\tPathComponentMax: %d Status: %d",
 216                                         le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics),
 217                                         le32_to_cpu(tcon->fsAttrInfo.Attributes),
 218                                         le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength),
 219                                         tcon->tidStatus);
 220                                 if (dev_type == FILE_DEVICE_DISK)
 221                                         seq_puts(m, " type: DISK ");
 222                                 else if (dev_type == FILE_DEVICE_CD_ROM)
 223                                         seq_puts(m, " type: CDROM ");
 224                                 else
 225                                         seq_printf(m, " type: %d ", dev_type);
 226                                 if (server->ops->dump_share_caps)
 227                                         server->ops->dump_share_caps(m, tcon);
 228
 229                                 if (tcon->need_reconnect)
 230                                         seq_puts(m, "\tDISCONNECTED ");
 231                                 seq_putc(m, '\n');
 232                         }
 233
 234                         seq_puts(m, "\n\tMIDs:\n");
 235
 236                         spin_lock(&GlobalMid_Lock);
 237                         list_for_each(tmp3, &server->pending_mid_q) {
 238                                 mid_entry = list_entry(tmp3, struct mid_q_entry,
 239                                         qhead);
 240                                 seq_printf(m, "\tState: %d com: %d pid:"
 241                                               " %d cbdata: %p mid %llu\n",
 242                                               mid_entry->mid_state,
 243                                               le16_to_cpu(mid_entry->command),
 244                                               mid_entry->pid,
 245                                               mid_entry->callback_data,
 246                                               mid_entry->mid);
 247                         }
 248                         spin_unlock(&GlobalMid_Lock);
 249                 }
 250         }
 251         spin_unlock(&cifs_tcp_ses_lock);
 252         seq_putc(m, '\n');
 253
 254         /* BB add code to dump additional info such as TCP session info now */
 255         return 0;
 256 }
 257
 258 static int cifs_debug_data_proc_open(struct inode *inode, struct file *file)
 259 {
 260         return single_open(file, cifs_debug_data_proc_show, NULL);
 261 }
 262
 263 static const struct file_operations cifs_debug_data_proc_fops = {
 264         .owner          = THIS_MODULE,
 265         .open           = cifs_debug_data_proc_open,
 266         .read           = seq_read,
 267         .llseek         = seq_lseek,
 268         .release        = single_release,
 269 };
 270
 271 #ifdef CONFIG_CIFS_STATS
 272 static ssize_t cifs_stats_proc_write(struct file *file,
 273                 const char __user *buffer, size_t count, loff_t *ppos)
 274 {
 275         bool bv;
 276         int rc;
 277         struct list_head *tmp1, *tmp2, *tmp3;
 278         struct TCP_Server_Info *server;
 279         struct cifs_ses *ses;
 280         struct cifs_tcon *tcon;
 281
 282         rc = kstrtobool_from_user(buffer, count, &bv);
 283         if (rc == 0) {
 284 #ifdef CONFIG_CIFS_STATS2
 285                 atomic_set(&totBufAllocCount, 0);
 286                 atomic_set(&totSmBufAllocCount, 0);
 287 #endif /* CONFIG_CIFS_STATS2 */
 288                 spin_lock(&GlobalMid_Lock);
 289                 GlobalMaxActiveXid = 0;
 290                 GlobalCurrentXid = 0;
 291                 spin_unlock(&GlobalMid_Lock);
 292                 spin_lock(&cifs_tcp_ses_lock);
 293                 list_for_each(tmp1, &cifs_tcp_ses_list) {
 294                         server = list_entry(tmp1, struct TCP_Server_Info,
 295                                             tcp_ses_list);
 296                         list_for_each(tmp2, &server->smb_ses_list) {
 297                                 ses = list_entry(tmp2, struct cifs_ses,
 298                                                  smb_ses_list);
 299                                 list_for_each(tmp3, &ses->tcon_list) {
 300                                         tcon = list_entry(tmp3,
 301                                                           struct cifs_tcon,
 302                                                           tcon_list);
 303                                         atomic_set(&tcon->num_smbs_sent, 0);
 304                                         spin_lock(&tcon->stat_lock);
 305                                         tcon->bytes_read = 0;
 306                                         tcon->bytes_written = 0;
 307                                         spin_unlock(&tcon->stat_lock);
 308                                         if (server->ops->clear_stats)
 309                                                 server->ops->clear_stats(tcon);
 310                                 }
 311                         }
 312                 }
 313                 spin_unlock(&cifs_tcp_ses_lock);
 314         } else {
 315                 return rc;
 316         }
 317
 318         return count;
 319 }
 320
 321 static int cifs_stats_proc_show(struct seq_file *m, void *v)
 322 {
 323         int i;
 324         struct list_head *tmp1, *tmp2, *tmp3;
 325         struct TCP_Server_Info *server;
 326         struct cifs_ses *ses;
 327         struct cifs_tcon *tcon;
 328
 329         seq_printf(m,
 330                         "Resources in use\nCIFS Session: %d\n",
 331                         sesInfoAllocCount.counter);
 332         seq_printf(m, "Share (unique mount targets): %d\n",
 333                         tconInfoAllocCount.counter);
 334         seq_printf(m, "SMB Request/Response Buffer: %d Pool size: %d\n",
 335                         bufAllocCount.counter,
 336                         cifs_min_rcv + tcpSesAllocCount.counter);
 337         seq_printf(m, "SMB Small Req/Resp Buffer: %d Pool size: %d\n",
 338                         smBufAllocCount.counter, cifs_min_small);
 339 #ifdef CONFIG_CIFS_STATS2
 340         seq_printf(m, "Total Large %d Small %d Allocations\n",
 341                                 atomic_read(&totBufAllocCount),
 342                                 atomic_read(&totSmBufAllocCount));
 343 #endif /* CONFIG_CIFS_STATS2 */
 344
 345         seq_printf(m, "Operations (MIDs): %d\n", atomic_read(&midCount));
 346         seq_printf(m,
 347                 "\n%d session %d share reconnects\n",
 348                 tcpSesReconnectCount.counter, tconInfoReconnectCount.counter);
 349
 350         seq_printf(m,
 351                 "Total vfs operations: %d maximum at one time: %d\n",
 352                 GlobalCurrentXid, GlobalMaxActiveXid);
 353
 354         i = 0;
 355         spin_lock(&cifs_tcp_ses_lock);
 356         list_for_each(tmp1, &cifs_tcp_ses_list) {
 357                 server = list_entry(tmp1, struct TCP_Server_Info,
 358                                     tcp_ses_list);
 359                 list_for_each(tmp2, &server->smb_ses_list) {
 360                         ses = list_entry(tmp2, struct cifs_ses,
 361                                          smb_ses_list);
 362                         list_for_each(tmp3, &ses->tcon_list) {
 363                                 tcon = list_entry(tmp3,
 364                                                   struct cifs_tcon,
 365                                                   tcon_list);
 366                                 i++;
 367                                 seq_printf(m, "\n%d) %s", i, tcon->treeName);
 368                                 if (tcon->need_reconnect)
 369                                         seq_puts(m, "\tDISCONNECTED ");
 370                                 seq_printf(m, "\nSMBs: %d",
 371                                            atomic_read(&tcon->num_smbs_sent));
 372                                 if (server->ops->print_stats)
 373                                         server->ops->print_stats(m, tcon);
 374                         }
 375                 }
 376         }
 377         spin_unlock(&cifs_tcp_ses_lock);
 378
 379         seq_putc(m, '\n');
 380         return 0;
 381 }
 382
 383 static int cifs_stats_proc_open(struct inode *inode, struct file *file)
 384 {
 385         return single_open(file, cifs_stats_proc_show, NULL);
 386 }
 387
 388 static const struct file_operations cifs_stats_proc_fops = {
 389         .owner          = THIS_MODULE,
 390         .open           = cifs_stats_proc_open,
 391         .read           = seq_read,
 392         .llseek         = seq_lseek,
 393         .release        = single_release,
 394         .write          = cifs_stats_proc_write,
 395 };
 396 #endif /* STATS */
 397
 398 static struct proc_dir_entry *proc_fs_cifs;
 399 static const struct file_operations cifsFYI_proc_fops;
 400 static const struct file_operations cifs_lookup_cache_proc_fops;
 401 static const struct file_operations traceSMB_proc_fops;
 402 static const struct file_operations cifs_security_flags_proc_fops;
 403 static const struct file_operations cifs_linux_ext_proc_fops;
 404
 405 void
 406 cifs_proc_init(void)
 407 {
 408         proc_fs_cifs = proc_mkdir("fs/cifs", NULL);
 409         if (proc_fs_cifs == NULL)
 410                 return;
 411
 412         proc_create("DebugData", 0, proc_fs_cifs, &cifs_debug_data_proc_fops);
 413
 414 #ifdef CONFIG_CIFS_STATS
 415         proc_create("Stats", 0, proc_fs_cifs, &cifs_stats_proc_fops);
 416 #endif /* STATS */
 417         proc_create("cifsFYI", 0, proc_fs_cifs, &cifsFYI_proc_fops);
 418         proc_create("traceSMB", 0, proc_fs_cifs, &traceSMB_proc_fops);
 419         proc_create("LinuxExtensionsEnabled", 0, proc_fs_cifs,
 420                     &cifs_linux_ext_proc_fops);
 421         proc_create("SecurityFlags", 0, proc_fs_cifs,
 422                     &cifs_security_flags_proc_fops);
 423         proc_create("LookupCacheEnabled", 0, proc_fs_cifs,
 424                     &cifs_lookup_cache_proc_fops);
 425 }
 426
 427 void
 428 cifs_proc_clean(void)
 429 {
 430         if (proc_fs_cifs == NULL)
 431                 return;
 432
 433         remove_proc_entry("DebugData", proc_fs_cifs);
 434         remove_proc_entry("cifsFYI", proc_fs_cifs);
 435         remove_proc_entry("traceSMB", proc_fs_cifs);
 436 #ifdef CONFIG_CIFS_STATS
 437         remove_proc_entry("Stats", proc_fs_cifs);
 438 #endif
 439         remove_proc_entry("SecurityFlags", proc_fs_cifs);
 440         remove_proc_entry("LinuxExtensionsEnabled", proc_fs_cifs);
 441         remove_proc_entry("LookupCacheEnabled", proc_fs_cifs);
 442         remove_proc_entry("fs/cifs", NULL);
 443 }
 444
 445 static int cifsFYI_proc_show(struct seq_file *m, void *v)
 446 {
 447         seq_printf(m, "%d\n", cifsFYI);
 448         return 0;
 449 }
 450
 451 static int cifsFYI_proc_open(struct inode *inode, struct file *file)
 452 {
 453         return single_open(file, cifsFYI_proc_show, NULL);
 454 }
 455
 456 static ssize_t cifsFYI_proc_write(struct file *file, const char __user *buffer,
 457                 size_t count, loff_t *ppos)
 458 {
 459         char c[2] = { '\0' };
 460         bool bv;
 461         int rc;
 462
 463         rc = get_user(c[0], buffer);
 464         if (rc)
 465                 return rc;
 466         if (strtobool(c, &bv) == 0)
 467                 cifsFYI = bv;
 468         else if ((c[0] > '1') && (c[0] <= '9'))
 469                 cifsFYI = (int) (c[0] - '0'); /* see cifs_debug.h for meanings */
 470
 471         return count;
 472 }
 473
 474 static const struct file_operations cifsFYI_proc_fops = {
 475         .owner          = THIS_MODULE,
 476         .open           = cifsFYI_proc_open,
 477         .read           = seq_read,
 478         .llseek         = seq_lseek,
 479         .release        = single_release,
 480         .write          = cifsFYI_proc_write,
 481 };
 482
 483 static int cifs_linux_ext_proc_show(struct seq_file *m, void *v)
 484 {
 485         seq_printf(m, "%d\n", linuxExtEnabled);
 486         return 0;
 487 }
 488
 489 static int cifs_linux_ext_proc_open(struct inode *inode, struct file *file)
 490 {
 491         return single_open(file, cifs_linux_ext_proc_show, NULL);
 492 }
 493
 494 static ssize_t cifs_linux_ext_proc_write(struct file *file,
 495                 const char __user *buffer, size_t count, loff_t *ppos)
 496 {
 497         int rc;
 498
 499         rc = kstrtobool_from_user(buffer, count, &linuxExtEnabled);
 500         if (rc)
 501                 return rc;
 502
 503         return count;
 504 }
 505
 506 static const struct file_operations cifs_linux_ext_proc_fops = {
 507         .owner          = THIS_MODULE,
 508         .open           = cifs_linux_ext_proc_open,
 509         .read           = seq_read,
 510         .llseek         = seq_lseek,
 511         .release        = single_release,
 512         .write          = cifs_linux_ext_proc_write,
 513 };
 514
 515 static int cifs_lookup_cache_proc_show(struct seq_file *m, void *v)
 516 {
 517         seq_printf(m, "%d\n", lookupCacheEnabled);
 518         return 0;
 519 }
 520
 521 static int cifs_lookup_cache_proc_open(struct inode *inode, struct file *file)
 522 {
 523         return single_open(file, cifs_lookup_cache_proc_show, NULL);
 524 }
 525
 526 static ssize_t cifs_lookup_cache_proc_write(struct file *file,
 527                 const char __user *buffer, size_t count, loff_t *ppos)
 528 {
 529         int rc;
 530
 531         rc = kstrtobool_from_user(buffer, count, &lookupCacheEnabled);
 532         if (rc)
 533                 return rc;
 534
 535         return count;
 536 }
 537
 538 static const struct file_operations cifs_lookup_cache_proc_fops = {
 539         .owner          = THIS_MODULE,
 540         .open           = cifs_lookup_cache_proc_open,
 541         .read           = seq_read,
 542         .llseek         = seq_lseek,
 543         .release        = single_release,
 544         .write          = cifs_lookup_cache_proc_write,
 545 };
 546
 547 static int traceSMB_proc_show(struct seq_file *m, void *v)
 548 {
 549         seq_printf(m, "%d\n", traceSMB);
 550         return 0;
 551 }
 552
 553 static int traceSMB_proc_open(struct inode *inode, struct file *file)
 554 {
 555         return single_open(file, traceSMB_proc_show, NULL);
 556 }
 557
 558 static ssize_t traceSMB_proc_write(struct file *file, const char __user *buffer,
 559                 size_t count, loff_t *ppos)
 560 {
 561         int rc;
 562
 563         rc = kstrtobool_from_user(buffer, count, &traceSMB);
 564         if (rc)
 565                 return rc;
 566
 567         return count;
 568 }
 569
 570 static const struct file_operations traceSMB_proc_fops = {
 571         .owner          = THIS_MODULE,
 572         .open           = traceSMB_proc_open,
 573         .read           = seq_read,
 574         .llseek         = seq_lseek,
 575         .release        = single_release,
 576         .write          = traceSMB_proc_write,
 577 };
 578
 579 static int cifs_security_flags_proc_show(struct seq_file *m, void *v)
 580 {
 581         seq_printf(m, "0x%x\n", global_secflags);
 582         return 0;
 583 }
 584
 585 static int cifs_security_flags_proc_open(struct inode *inode, struct file *file)
 586 {
 587         return single_open(file, cifs_security_flags_proc_show, NULL);
 588 }
 589
 590 /*
 591  * Ensure that if someone sets a MUST flag, that we disable all other MAY
 592  * flags except for the ones corresponding to the given MUST flag. If there are
 593  * multiple MUST flags, then try to prefer more secure ones.
 594  */
 595 static void
 596 cifs_security_flags_handle_must_flags(unsigned int *flags)
 597 {
 598         unsigned int signflags = *flags & CIFSSEC_MUST_SIGN;
 599
 600         if ((*flags & CIFSSEC_MUST_KRB5) == CIFSSEC_MUST_KRB5)
 601                 *flags = CIFSSEC_MUST_KRB5;
 602         else if ((*flags & CIFSSEC_MUST_NTLMSSP) == CIFSSEC_MUST_NTLMSSP)
 603                 *flags = CIFSSEC_MUST_NTLMSSP;
 604         else if ((*flags & CIFSSEC_MUST_NTLMV2) == CIFSSEC_MUST_NTLMV2)
 605                 *flags = CIFSSEC_MUST_NTLMV2;
 606         else if ((*flags & CIFSSEC_MUST_NTLM) == CIFSSEC_MUST_NTLM)
 607                 *flags = CIFSSEC_MUST_NTLM;
 608         else if (CIFSSEC_MUST_LANMAN &&
 609                  (*flags & CIFSSEC_MUST_LANMAN) == CIFSSEC_MUST_LANMAN)
 610                 *flags = CIFSSEC_MUST_LANMAN;
 611         else if (CIFSSEC_MUST_PLNTXT &&
 612                  (*flags & CIFSSEC_MUST_PLNTXT) == CIFSSEC_MUST_PLNTXT)
 613                 *flags = CIFSSEC_MUST_PLNTXT;
 614
 615         *flags |= signflags;
 616 }
 617
 618 static ssize_t cifs_security_flags_proc_write(struct file *file,
 619                 const char __user *buffer, size_t count, loff_t *ppos)
 620 {
 621         int rc;
 622         unsigned int flags;
 623         char flags_string[12];
 624         bool bv;
 625
 626         if ((count < 1) || (count > 11))
 627                 return -EINVAL;
 628
 629         memset(flags_string, 0, 12);
 630
 631         if (copy_from_user(flags_string, buffer, count))
 632                 return -EFAULT;
 633
 634         if (count < 3) {
 635                 /* single char or single char followed by null */
 636                 if (strtobool(flags_string, &bv) == 0) {
 637                         global_secflags = bv ? CIFSSEC_MAX : CIFSSEC_DEF;
 638                         return count;
 639                 } else if (!isdigit(flags_string[0])) {
 640                         cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 641                                         flags_string);
 642                         return -EINVAL;
 643                 }
 644         }
 645
 646         /* else we have a number */
 647         rc = kstrtouint(flags_string, 0, &flags);
 648         if (rc) {
 649                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 650                                 flags_string);
 651                 return rc;
 652         }
 653
 654         cifs_dbg(FYI, "sec flags 0x%x\n", flags);
 655
 656         if (flags == 0)  {
 657                 cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", flags_string);
 658                 return -EINVAL;
 659         }
 660
 661         if (flags & ~CIFSSEC_MASK) {
 662                 cifs_dbg(VFS, "Unsupported security flags: 0x%x\n",
 663                          flags & ~CIFSSEC_MASK);
 664                 return -EINVAL;
 665         }
 666
 667         cifs_security_flags_handle_must_flags(&flags);
 668
 669         /* flags look ok - update the global security flags for cifs module */
 670         global_secflags = flags;
 671         if (global_secflags & CIFSSEC_MUST_SIGN) {
 672                 /* requiring signing implies signing is allowed */
 673                 global_secflags |= CIFSSEC_MAY_SIGN;
 674                 cifs_dbg(FYI, "packet signing now required\n");
 675         } else if ((global_secflags & CIFSSEC_MAY_SIGN) == 0) {
 676                 cifs_dbg(FYI, "packet signing disabled\n");
 677         }
 678         /* BB should we turn on MAY flags for other MUST options? */
 679         return count;
 680 }
 681
 682 static const struct file_operations cifs_security_flags_proc_fops = {
 683         .owner          = THIS_MODULE,
 684         .open           = cifs_security_flags_proc_open,
 685         .read           = seq_read,
 686         .llseek         = seq_lseek,
 687         .release        = single_release,
 688         .write          = cifs_security_flags_proc_write,
 689 };
 690 #else
 691 inline void cifs_proc_init(void)
 692 {
 693 }
 694
 695 inline void cifs_proc_clean(void)
 696 {
 697 }
 698 #endif /* PROC_FS */