linux/fs/cifs/cifs_debug.c
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   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
  34void
  35cifs_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
  43void 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
  59void 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
  71void 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
 110static 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) entry for %s not fully "
 164                                           "displayed\n\t", i, ses->serverName);
 165                        } else {
 166                                seq_printf(m,
 167                                    "\n%d) Name: %s  Domain: %s Uses: %d OS:"
 168                                    " %s\n\tNOS: %s\tCapability: 0x%x\n\tSMB"
 169                                    " session status: %d\t",
 170                                i, ses->serverName, ses->serverDomain,
 171                                ses->ses_count, ses->serverOS, ses->serverNOS,
 172                                ses->capabilities, ses->status);
 173                        }
 174                        seq_printf(m, "TCP status: %d\n\tLocal Users To "
 175                                   "Server: %d SecMode: 0x%x Req On Wire: %d",
 176                                   server->tcpStatus, server->srv_count,
 177                                   server->sec_mode, in_flight(server));
 178
 179#ifdef CONFIG_CIFS_STATS2
 180                        seq_printf(m, " In Send: %d In MaxReq Wait: %d",
 181                                atomic_read(&server->in_send),
 182                                atomic_read(&server->num_waiters));
 183#endif
 184
 185                        seq_puts(m, "\n\tShares:");
 186                        j = 0;
 187                        list_for_each(tmp3, &ses->tcon_list) {
 188                                tcon = list_entry(tmp3, struct cifs_tcon,
 189                                                  tcon_list);
 190                                ++j;
 191                                dev_type = le32_to_cpu(tcon->fsDevInfo.DeviceType);
 192                                seq_printf(m, "\n\t%d) %s Mounts: %d ", j,
 193                                           tcon->treeName, tcon->tc_count);
 194                                if (tcon->nativeFileSystem) {
 195                                        seq_printf(m, "Type: %s ",
 196                                                   tcon->nativeFileSystem);
 197                                }
 198                                seq_printf(m, "DevInfo: 0x%x Attributes: 0x%x"
 199                                        "\n\tPathComponentMax: %d Status: %d",
 200                                        le32_to_cpu(tcon->fsDevInfo.DeviceCharacteristics),
 201                                        le32_to_cpu(tcon->fsAttrInfo.Attributes),
 202                                        le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength),
 203                                        tcon->tidStatus);
 204                                if (dev_type == FILE_DEVICE_DISK)
 205                                        seq_puts(m, " type: DISK ");
 206                                else if (dev_type == FILE_DEVICE_CD_ROM)
 207                                        seq_puts(m, " type: CDROM ");
 208                                else
 209                                        seq_printf(m, " type: %d ", dev_type);
 210                                if (server->ops->dump_share_caps)
 211                                        server->ops->dump_share_caps(m, tcon);
 212
 213                                if (tcon->need_reconnect)
 214                                        seq_puts(m, "\tDISCONNECTED ");
 215                                seq_putc(m, '\n');
 216                        }
 217
 218                        seq_puts(m, "\n\tMIDs:\n");
 219
 220                        spin_lock(&GlobalMid_Lock);
 221                        list_for_each(tmp3, &server->pending_mid_q) {
 222                                mid_entry = list_entry(tmp3, struct mid_q_entry,
 223                                        qhead);
 224                                seq_printf(m, "\tState: %d com: %d pid:"
 225                                              " %d cbdata: %p mid %llu\n",
 226                                              mid_entry->mid_state,
 227                                              le16_to_cpu(mid_entry->command),
 228                                              mid_entry->pid,
 229                                              mid_entry->callback_data,
 230                                              mid_entry->mid);
 231                        }
 232                        spin_unlock(&GlobalMid_Lock);
 233                }
 234        }
 235        spin_unlock(&cifs_tcp_ses_lock);
 236        seq_putc(m, '\n');
 237
 238        /* BB add code to dump additional info such as TCP session info now */
 239        return 0;
 240}
 241
 242static int cifs_debug_data_proc_open(struct inode *inode, struct file *file)
 243{
 244        return single_open(file, cifs_debug_data_proc_show, NULL);
 245}
 246
 247static const struct file_operations cifs_debug_data_proc_fops = {
 248        .open           = cifs_debug_data_proc_open,
 249        .read           = seq_read,
 250        .llseek         = seq_lseek,
 251        .release        = single_release,
 252};
 253
 254#ifdef CONFIG_CIFS_STATS
 255static ssize_t cifs_stats_proc_write(struct file *file,
 256                const char __user *buffer, size_t count, loff_t *ppos)
 257{
 258        bool bv;
 259        int rc;
 260        struct list_head *tmp1, *tmp2, *tmp3;
 261        struct TCP_Server_Info *server;
 262        struct cifs_ses *ses;
 263        struct cifs_tcon *tcon;
 264
 265        rc = kstrtobool_from_user(buffer, count, &bv);
 266        if (rc == 0) {
 267#ifdef CONFIG_CIFS_STATS2
 268                atomic_set(&totBufAllocCount, 0);
 269                atomic_set(&totSmBufAllocCount, 0);
 270#endif /* CONFIG_CIFS_STATS2 */
 271                spin_lock(&cifs_tcp_ses_lock);
 272                list_for_each(tmp1, &cifs_tcp_ses_list) {
 273                        server = list_entry(tmp1, struct TCP_Server_Info,
 274                                            tcp_ses_list);
 275                        list_for_each(tmp2, &server->smb_ses_list) {
 276                                ses = list_entry(tmp2, struct cifs_ses,
 277                                                 smb_ses_list);
 278                                list_for_each(tmp3, &ses->tcon_list) {
 279                                        tcon = list_entry(tmp3,
 280                                                          struct cifs_tcon,
 281                                                          tcon_list);
 282                                        atomic_set(&tcon->num_smbs_sent, 0);
 283                                        if (server->ops->clear_stats)
 284                                                server->ops->clear_stats(tcon);
 285                                }
 286                        }
 287                }
 288                spin_unlock(&cifs_tcp_ses_lock);
 289        } else {
 290                return rc;
 291        }
 292
 293        return count;
 294}
 295
 296static int cifs_stats_proc_show(struct seq_file *m, void *v)
 297{
 298        int i;
 299        struct list_head *tmp1, *tmp2, *tmp3;
 300        struct TCP_Server_Info *server;
 301        struct cifs_ses *ses;
 302        struct cifs_tcon *tcon;
 303
 304        seq_printf(m,
 305                        "Resources in use\nCIFS Session: %d\n",
 306                        sesInfoAllocCount.counter);
 307        seq_printf(m, "Share (unique mount targets): %d\n",
 308                        tconInfoAllocCount.counter);
 309        seq_printf(m, "SMB Request/Response Buffer: %d Pool size: %d\n",
 310                        bufAllocCount.counter,
 311                        cifs_min_rcv + tcpSesAllocCount.counter);
 312        seq_printf(m, "SMB Small Req/Resp Buffer: %d Pool size: %d\n",
 313                        smBufAllocCount.counter, cifs_min_small);
 314#ifdef CONFIG_CIFS_STATS2
 315        seq_printf(m, "Total Large %d Small %d Allocations\n",
 316                                atomic_read(&totBufAllocCount),
 317                                atomic_read(&totSmBufAllocCount));
 318#endif /* CONFIG_CIFS_STATS2 */
 319
 320        seq_printf(m, "Operations (MIDs): %d\n", atomic_read(&midCount));
 321        seq_printf(m,
 322                "\n%d session %d share reconnects\n",
 323                tcpSesReconnectCount.counter, tconInfoReconnectCount.counter);
 324
 325        seq_printf(m,
 326                "Total vfs operations: %d maximum at one time: %d\n",
 327                GlobalCurrentXid, GlobalMaxActiveXid);
 328
 329        i = 0;
 330        spin_lock(&cifs_tcp_ses_lock);
 331        list_for_each(tmp1, &cifs_tcp_ses_list) {
 332                server = list_entry(tmp1, struct TCP_Server_Info,
 333                                    tcp_ses_list);
 334                list_for_each(tmp2, &server->smb_ses_list) {
 335                        ses = list_entry(tmp2, struct cifs_ses,
 336                                         smb_ses_list);
 337                        list_for_each(tmp3, &ses->tcon_list) {
 338                                tcon = list_entry(tmp3,
 339                                                  struct cifs_tcon,
 340                                                  tcon_list);
 341                                i++;
 342                                seq_printf(m, "\n%d) %s", i, tcon->treeName);
 343                                if (tcon->need_reconnect)
 344                                        seq_puts(m, "\tDISCONNECTED ");
 345                                seq_printf(m, "\nSMBs: %d",
 346                                           atomic_read(&tcon->num_smbs_sent));
 347                                if (server->ops->print_stats)
 348                                        server->ops->print_stats(m, tcon);
 349                        }
 350                }
 351        }
 352        spin_unlock(&cifs_tcp_ses_lock);
 353
 354        seq_putc(m, '\n');
 355        return 0;
 356}
 357
 358static int cifs_stats_proc_open(struct inode *inode, struct file *file)
 359{
 360        return single_open(file, cifs_stats_proc_show, NULL);
 361}
 362
 363static const struct file_operations cifs_stats_proc_fops = {
 364        .open           = cifs_stats_proc_open,
 365        .read           = seq_read,
 366        .llseek         = seq_lseek,
 367        .release        = single_release,
 368        .write          = cifs_stats_proc_write,
 369};
 370#endif /* STATS */
 371
 372static struct proc_dir_entry *proc_fs_cifs;
 373static const struct file_operations cifsFYI_proc_fops;
 374static const struct file_operations cifs_lookup_cache_proc_fops;
 375static const struct file_operations traceSMB_proc_fops;
 376static const struct file_operations cifs_security_flags_proc_fops;
 377static const struct file_operations cifs_linux_ext_proc_fops;
 378
 379void
 380cifs_proc_init(void)
 381{
 382        proc_fs_cifs = proc_mkdir("fs/cifs", NULL);
 383        if (proc_fs_cifs == NULL)
 384                return;
 385
 386        proc_create("DebugData", 0, proc_fs_cifs, &cifs_debug_data_proc_fops);
 387
 388#ifdef CONFIG_CIFS_STATS
 389        proc_create("Stats", 0, proc_fs_cifs, &cifs_stats_proc_fops);
 390#endif /* STATS */
 391        proc_create("cifsFYI", 0, proc_fs_cifs, &cifsFYI_proc_fops);
 392        proc_create("traceSMB", 0, proc_fs_cifs, &traceSMB_proc_fops);
 393        proc_create("LinuxExtensionsEnabled", 0, proc_fs_cifs,
 394                    &cifs_linux_ext_proc_fops);
 395        proc_create("SecurityFlags", 0, proc_fs_cifs,
 396                    &cifs_security_flags_proc_fops);
 397        proc_create("LookupCacheEnabled", 0, proc_fs_cifs,
 398                    &cifs_lookup_cache_proc_fops);
 399}
 400
 401void
 402cifs_proc_clean(void)
 403{
 404        if (proc_fs_cifs == NULL)
 405                return;
 406
 407        remove_proc_entry("DebugData", proc_fs_cifs);
 408        remove_proc_entry("cifsFYI", proc_fs_cifs);
 409        remove_proc_entry("traceSMB", proc_fs_cifs);
 410#ifdef CONFIG_CIFS_STATS
 411        remove_proc_entry("Stats", proc_fs_cifs);
 412#endif
 413        remove_proc_entry("SecurityFlags", proc_fs_cifs);
 414        remove_proc_entry("LinuxExtensionsEnabled", proc_fs_cifs);
 415        remove_proc_entry("LookupCacheEnabled", proc_fs_cifs);
 416        remove_proc_entry("fs/cifs", NULL);
 417}
 418
 419static int cifsFYI_proc_show(struct seq_file *m, void *v)
 420{
 421        seq_printf(m, "%d\n", cifsFYI);
 422        return 0;
 423}
 424
 425static int cifsFYI_proc_open(struct inode *inode, struct file *file)
 426{
 427        return single_open(file, cifsFYI_proc_show, NULL);
 428}
 429
 430static ssize_t cifsFYI_proc_write(struct file *file, const char __user *buffer,
 431                size_t count, loff_t *ppos)
 432{
 433        char c[2] = { '\0' };
 434        bool bv;
 435        int rc;
 436
 437        rc = get_user(c[0], buffer);
 438        if (rc)
 439                return rc;
 440        if (strtobool(c, &bv) == 0)
 441                cifsFYI = bv;
 442        else if ((c[0] > '1') && (c[0] <= '9'))
 443                cifsFYI = (int) (c[0] - '0'); /* see cifs_debug.h for meanings */
 444
 445        return count;
 446}
 447
 448static const struct file_operations cifsFYI_proc_fops = {
 449        .open           = cifsFYI_proc_open,
 450        .read           = seq_read,
 451        .llseek         = seq_lseek,
 452        .release        = single_release,
 453        .write          = cifsFYI_proc_write,
 454};
 455
 456static int cifs_linux_ext_proc_show(struct seq_file *m, void *v)
 457{
 458        seq_printf(m, "%d\n", linuxExtEnabled);
 459        return 0;
 460}
 461
 462static int cifs_linux_ext_proc_open(struct inode *inode, struct file *file)
 463{
 464        return single_open(file, cifs_linux_ext_proc_show, NULL);
 465}
 466
 467static ssize_t cifs_linux_ext_proc_write(struct file *file,
 468                const char __user *buffer, size_t count, loff_t *ppos)
 469{
 470        int rc;
 471
 472        rc = kstrtobool_from_user(buffer, count, &linuxExtEnabled);
 473        if (rc)
 474                return rc;
 475
 476        return count;
 477}
 478
 479static const struct file_operations cifs_linux_ext_proc_fops = {
 480        .open           = cifs_linux_ext_proc_open,
 481        .read           = seq_read,
 482        .llseek         = seq_lseek,
 483        .release        = single_release,
 484        .write          = cifs_linux_ext_proc_write,
 485};
 486
 487static int cifs_lookup_cache_proc_show(struct seq_file *m, void *v)
 488{
 489        seq_printf(m, "%d\n", lookupCacheEnabled);
 490        return 0;
 491}
 492
 493static int cifs_lookup_cache_proc_open(struct inode *inode, struct file *file)
 494{
 495        return single_open(file, cifs_lookup_cache_proc_show, NULL);
 496}
 497
 498static ssize_t cifs_lookup_cache_proc_write(struct file *file,
 499                const char __user *buffer, size_t count, loff_t *ppos)
 500{
 501        int rc;
 502
 503        rc = kstrtobool_from_user(buffer, count, &lookupCacheEnabled);
 504        if (rc)
 505                return rc;
 506
 507        return count;
 508}
 509
 510static const struct file_operations cifs_lookup_cache_proc_fops = {
 511        .open           = cifs_lookup_cache_proc_open,
 512        .read           = seq_read,
 513        .llseek         = seq_lseek,
 514        .release        = single_release,
 515        .write          = cifs_lookup_cache_proc_write,
 516};
 517
 518static int traceSMB_proc_show(struct seq_file *m, void *v)
 519{
 520        seq_printf(m, "%d\n", traceSMB);
 521        return 0;
 522}
 523
 524static int traceSMB_proc_open(struct inode *inode, struct file *file)
 525{
 526        return single_open(file, traceSMB_proc_show, NULL);
 527}
 528
 529static ssize_t traceSMB_proc_write(struct file *file, const char __user *buffer,
 530                size_t count, loff_t *ppos)
 531{
 532        int rc;
 533
 534        rc = kstrtobool_from_user(buffer, count, &traceSMB);
 535        if (rc)
 536                return rc;
 537
 538        return count;
 539}
 540
 541static const struct file_operations traceSMB_proc_fops = {
 542        .open           = traceSMB_proc_open,
 543        .read           = seq_read,
 544        .llseek         = seq_lseek,
 545        .release        = single_release,
 546        .write          = traceSMB_proc_write,
 547};
 548
 549static int cifs_security_flags_proc_show(struct seq_file *m, void *v)
 550{
 551        seq_printf(m, "0x%x\n", global_secflags);
 552        return 0;
 553}
 554
 555static int cifs_security_flags_proc_open(struct inode *inode, struct file *file)
 556{
 557        return single_open(file, cifs_security_flags_proc_show, NULL);
 558}
 559
 560/*
 561 * Ensure that if someone sets a MUST flag, that we disable all other MAY
 562 * flags except for the ones corresponding to the given MUST flag. If there are
 563 * multiple MUST flags, then try to prefer more secure ones.
 564 */
 565static void
 566cifs_security_flags_handle_must_flags(unsigned int *flags)
 567{
 568        unsigned int signflags = *flags & CIFSSEC_MUST_SIGN;
 569
 570        if ((*flags & CIFSSEC_MUST_KRB5) == CIFSSEC_MUST_KRB5)
 571                *flags = CIFSSEC_MUST_KRB5;
 572        else if ((*flags & CIFSSEC_MUST_NTLMSSP) == CIFSSEC_MUST_NTLMSSP)
 573                *flags = CIFSSEC_MUST_NTLMSSP;
 574        else if ((*flags & CIFSSEC_MUST_NTLMV2) == CIFSSEC_MUST_NTLMV2)
 575                *flags = CIFSSEC_MUST_NTLMV2;
 576        else if ((*flags & CIFSSEC_MUST_NTLM) == CIFSSEC_MUST_NTLM)
 577                *flags = CIFSSEC_MUST_NTLM;
 578        else if (CIFSSEC_MUST_LANMAN &&
 579                 (*flags & CIFSSEC_MUST_LANMAN) == CIFSSEC_MUST_LANMAN)
 580                *flags = CIFSSEC_MUST_LANMAN;
 581        else if (CIFSSEC_MUST_PLNTXT &&
 582                 (*flags & CIFSSEC_MUST_PLNTXT) == CIFSSEC_MUST_PLNTXT)
 583                *flags = CIFSSEC_MUST_PLNTXT;
 584
 585        *flags |= signflags;
 586}
 587
 588static ssize_t cifs_security_flags_proc_write(struct file *file,
 589                const char __user *buffer, size_t count, loff_t *ppos)
 590{
 591        int rc;
 592        unsigned int flags;
 593        char flags_string[12];
 594        bool bv;
 595
 596        if ((count < 1) || (count > 11))
 597                return -EINVAL;
 598
 599        memset(flags_string, 0, 12);
 600
 601        if (copy_from_user(flags_string, buffer, count))
 602                return -EFAULT;
 603
 604        if (count < 3) {
 605                /* single char or single char followed by null */
 606                if (strtobool(flags_string, &bv) == 0) {
 607                        global_secflags = bv ? CIFSSEC_MAX : CIFSSEC_DEF;
 608                        return count;
 609                } else if (!isdigit(flags_string[0])) {
 610                        cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 611                                        flags_string);
 612                        return -EINVAL;
 613                }
 614        }
 615
 616        /* else we have a number */
 617        rc = kstrtouint(flags_string, 0, &flags);
 618        if (rc) {
 619                cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
 620                                flags_string);
 621                return rc;
 622        }
 623
 624        cifs_dbg(FYI, "sec flags 0x%x\n", flags);
 625
 626        if (flags == 0)  {
 627                cifs_dbg(VFS, "Invalid SecurityFlags: %s\n", flags_string);
 628                return -EINVAL;
 629        }
 630
 631        if (flags & ~CIFSSEC_MASK) {
 632                cifs_dbg(VFS, "Unsupported security flags: 0x%x\n",
 633                         flags & ~CIFSSEC_MASK);
 634                return -EINVAL;
 635        }
 636
 637        cifs_security_flags_handle_must_flags(&flags);
 638
 639        /* flags look ok - update the global security flags for cifs module */
 640        global_secflags = flags;
 641        if (global_secflags & CIFSSEC_MUST_SIGN) {
 642                /* requiring signing implies signing is allowed */
 643                global_secflags |= CIFSSEC_MAY_SIGN;
 644                cifs_dbg(FYI, "packet signing now required\n");
 645        } else if ((global_secflags & CIFSSEC_MAY_SIGN) == 0) {
 646                cifs_dbg(FYI, "packet signing disabled\n");
 647        }
 648        /* BB should we turn on MAY flags for other MUST options? */
 649        return count;
 650}
 651
 652static const struct file_operations cifs_security_flags_proc_fops = {
 653        .open           = cifs_security_flags_proc_open,
 654        .read           = seq_read,
 655        .llseek         = seq_lseek,
 656        .release        = single_release,
 657        .write          = cifs_security_flags_proc_write,
 658};
 659#else
 660inline void cifs_proc_init(void)
 661{
 662}
 663
 664inline void cifs_proc_clean(void)
 665{
 666}
 667#endif /* PROC_FS */
 668