security/selinux/selinuxfs.c

   1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
   2  *
   3  *      Added conditional policy language extensions
   4  *
   5  *  Updated: Hewlett-Packard <paul.moore@hp.com>
   6  *
   7  *      Added support for the policy capability bitmap
   8  *
   9  * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
  10  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
  11  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
  12  *      This program is free software; you can redistribute it and/or modify
  13  *      it under the terms of the GNU General Public License as published by
  14  *      the Free Software Foundation, version 2.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/pagemap.h>
  19 #include <linux/slab.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/fs.h>
  22 #include <linux/mutex.h>
  23 #include <linux/init.h>
  24 #include <linux/string.h>
  25 #include <linux/security.h>
  26 #include <linux/major.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/percpu.h>
  29 #include <linux/audit.h>
  30 #include <linux/uaccess.h>
  31
  32 /* selinuxfs pseudo filesystem for exporting the security policy API.
  33    Based on the proc code and the fs/nfsd/nfsctl.c code. */
  34
  35 #include "flask.h"
  36 #include "avc.h"
  37 #include "avc_ss.h"
  38 #include "security.h"
  39 #include "objsec.h"
  40 #include "conditional.h"
  41
  42 /* Policy capability filenames */
  43 static char *policycap_names[] = {
  44         "network_peer_controls",
  45         "open_perms"
  46 };
  47
  48 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
  49
  50 static int __init checkreqprot_setup(char *str)
  51 {
  52         unsigned long checkreqprot;
  53         if (!strict_strtoul(str, 0, &checkreqprot))
  54                 selinux_checkreqprot = checkreqprot ? 1 : 0;
  55         return 1;
  56 }
  57 __setup("checkreqprot=", checkreqprot_setup);
  58
  59 static DEFINE_MUTEX(sel_mutex);
  60
  61 /* global data for booleans */
  62 static struct dentry *bool_dir;
  63 static int bool_num;
  64 static char **bool_pending_names;
  65 static int *bool_pending_values;
  66
  67 /* global data for classes */
  68 static struct dentry *class_dir;
  69 static unsigned long last_class_ino;
  70
  71 /* global data for policy capabilities */
  72 static struct dentry *policycap_dir;
  73
  74 extern void selnl_notify_setenforce(int val);
  75
  76 /* Check whether a task is allowed to use a security operation. */
  77 static int task_has_security(struct task_struct *tsk,
  78                              u32 perms)
  79 {
  80         const struct task_security_struct *tsec;
  81         u32 sid = 0;
  82
  83         rcu_read_lock();
  84         tsec = __task_cred(tsk)->security;
  85         if (tsec)
  86                 sid = tsec->sid;
  87         rcu_read_unlock();
  88         if (!tsec)
  89                 return -EACCES;
  90
  91         return avc_has_perm(sid, SECINITSID_SECURITY,
  92                             SECCLASS_SECURITY, perms, NULL);
  93 }
  94
  95 enum sel_inos {
  96         SEL_ROOT_INO = 2,
  97         SEL_LOAD,       /* load policy */
  98         SEL_ENFORCE,    /* get or set enforcing status */
  99         SEL_CONTEXT,    /* validate context */
 100         SEL_ACCESS,     /* compute access decision */
 101         SEL_CREATE,     /* compute create labeling decision */
 102         SEL_RELABEL,    /* compute relabeling decision */
 103         SEL_USER,       /* compute reachable user contexts */
 104         SEL_POLICYVERS, /* return policy version for this kernel */
 105         SEL_COMMIT_BOOLS, /* commit new boolean values */
 106         SEL_MLS,        /* return if MLS policy is enabled */
 107         SEL_DISABLE,    /* disable SELinux until next reboot */
 108         SEL_MEMBER,     /* compute polyinstantiation membership decision */
 109         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
 110         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
 111         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
 112         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
 113         SEL_INO_NEXT,   /* The next inode number to use */
 114 };
 115
 116 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
 117
 118 #define SEL_INITCON_INO_OFFSET          0x01000000
 119 #define SEL_BOOL_INO_OFFSET             0x02000000
 120 #define SEL_CLASS_INO_OFFSET            0x04000000
 121 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
 122 #define SEL_INO_MASK                    0x00ffffff
 123
 124 #define TMPBUFLEN       12
 125 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 126                                 size_t count, loff_t *ppos)
 127 {
 128         char tmpbuf[TMPBUFLEN];
 129         ssize_t length;
 130
 131         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
 132         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 133 }
 134
 135 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 136 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 137                                  size_t count, loff_t *ppos)
 138
 139 {
 140         char *page;
 141         ssize_t length;
 142         int new_value;
 143
 144         if (count >= PAGE_SIZE)
 145                 return -ENOMEM;
 146         if (*ppos != 0) {
 147                 /* No partial writes. */
 148                 return -EINVAL;
 149         }
 150         page = (char *)get_zeroed_page(GFP_KERNEL);
 151         if (!page)
 152                 return -ENOMEM;
 153         length = -EFAULT;
 154         if (copy_from_user(page, buf, count))
 155                 goto out;
 156
 157         length = -EINVAL;
 158         if (sscanf(page, "%d", &new_value) != 1)
 159                 goto out;
 160
 161         if (new_value != selinux_enforcing) {
 162                 length = task_has_security(current, SECURITY__SETENFORCE);
 163                 if (length)
 164                         goto out;
 165                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 166                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
 167                         new_value, selinux_enforcing,
 168                         audit_get_loginuid(current),
 169                         audit_get_sessionid(current));
 170                 selinux_enforcing = new_value;
 171                 if (selinux_enforcing)
 172                         avc_ss_reset(0);
 173                 selnl_notify_setenforce(selinux_enforcing);
 174         }
 175         length = count;
 176 out:
 177         free_page((unsigned long) page);
 178         return length;
 179 }
 180 #else
 181 #define sel_write_enforce NULL
 182 #endif
 183
 184 static const struct file_operations sel_enforce_ops = {
 185         .read           = sel_read_enforce,
 186         .write          = sel_write_enforce,
 187 };
 188
 189 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 190                                         size_t count, loff_t *ppos)
 191 {
 192         char tmpbuf[TMPBUFLEN];
 193         ssize_t length;
 194         ino_t ino = filp->f_path.dentry->d_inode->i_ino;
 195         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 196                 security_get_reject_unknown() : !security_get_allow_unknown();
 197
 198         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 199         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 200 }
 201
 202 static const struct file_operations sel_handle_unknown_ops = {
 203         .read           = sel_read_handle_unknown,
 204 };
 205
 206 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 207 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 208                                  size_t count, loff_t *ppos)
 209
 210 {
 211         char *page;
 212         ssize_t length;
 213         int new_value;
 214         extern int selinux_disable(void);
 215
 216         if (count >= PAGE_SIZE)
 217                 return -ENOMEM;
 218         if (*ppos != 0) {
 219                 /* No partial writes. */
 220                 return -EINVAL;
 221         }
 222         page = (char *)get_zeroed_page(GFP_KERNEL);
 223         if (!page)
 224                 return -ENOMEM;
 225         length = -EFAULT;
 226         if (copy_from_user(page, buf, count))
 227                 goto out;
 228
 229         length = -EINVAL;
 230         if (sscanf(page, "%d", &new_value) != 1)
 231                 goto out;
 232
 233         if (new_value) {
 234                 length = selinux_disable();
 235                 if (length < 0)
 236                         goto out;
 237                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 238                         "selinux=0 auid=%u ses=%u",
 239                         audit_get_loginuid(current),
 240                         audit_get_sessionid(current));
 241         }
 242
 243         length = count;
 244 out:
 245         free_page((unsigned long) page);
 246         return length;
 247 }
 248 #else
 249 #define sel_write_disable NULL
 250 #endif
 251
 252 static const struct file_operations sel_disable_ops = {
 253         .write          = sel_write_disable,
 254 };
 255
 256 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 257                                    size_t count, loff_t *ppos)
 258 {
 259         char tmpbuf[TMPBUFLEN];
 260         ssize_t length;
 261
 262         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 263         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 264 }
 265
 266 static const struct file_operations sel_policyvers_ops = {
 267         .read           = sel_read_policyvers,
 268 };
 269
 270 /* declaration for sel_write_load */
 271 static int sel_make_bools(void);
 272 static int sel_make_classes(void);
 273 static int sel_make_policycap(void);
 274
 275 /* declaration for sel_make_class_dirs */
 276 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
 277                         unsigned long *ino);
 278
 279 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 280                                 size_t count, loff_t *ppos)
 281 {
 282         char tmpbuf[TMPBUFLEN];
 283         ssize_t length;
 284
 285         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 286                            security_mls_enabled());
 287         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 288 }
 289
 290 static const struct file_operations sel_mls_ops = {
 291         .read           = sel_read_mls,
 292 };
 293
 294 static ssize_t sel_write_load(struct file *file, const char __user *buf,
 295                               size_t count, loff_t *ppos)
 296
 297 {
 298         int ret;
 299         ssize_t length;
 300         void *data = NULL;
 301
 302         mutex_lock(&sel_mutex);
 303
 304         length = task_has_security(current, SECURITY__LOAD_POLICY);
 305         if (length)
 306                 goto out;
 307
 308         if (*ppos != 0) {
 309                 /* No partial writes. */
 310                 length = -EINVAL;
 311                 goto out;
 312         }
 313
 314         if ((count > 64 * 1024 * 1024)
 315             || (data = vmalloc(count)) == NULL) {
 316                 length = -ENOMEM;
 317                 goto out;
 318         }
 319
 320         length = -EFAULT;
 321         if (copy_from_user(data, buf, count) != 0)
 322                 goto out;
 323
 324         length = security_load_policy(data, count);
 325         if (length)
 326                 goto out;
 327
 328         ret = sel_make_bools();
 329         if (ret) {
 330                 length = ret;
 331                 goto out1;
 332         }
 333
 334         ret = sel_make_classes();
 335         if (ret) {
 336                 length = ret;
 337                 goto out1;
 338         }
 339
 340         ret = sel_make_policycap();
 341         if (ret)
 342                 length = ret;
 343         else
 344                 length = count;
 345
 346 out1:
 347         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 348                 "policy loaded auid=%u ses=%u",
 349                 audit_get_loginuid(current),
 350                 audit_get_sessionid(current));
 351 out:
 352         mutex_unlock(&sel_mutex);
 353         vfree(data);
 354         return length;
 355 }
 356
 357 static const struct file_operations sel_load_ops = {
 358         .write          = sel_write_load,
 359 };
 360
 361 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 362 {
 363         char *canon;
 364         u32 sid, len;
 365         ssize_t length;
 366
 367         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
 368         if (length)
 369                 return length;
 370
 371         length = security_context_to_sid(buf, size, &sid);
 372         if (length < 0)
 373                 return length;
 374
 375         length = security_sid_to_context(sid, &canon, &len);
 376         if (length < 0)
 377                 return length;
 378
 379         if (len > SIMPLE_TRANSACTION_LIMIT) {
 380                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 381                         "payload max\n", __func__, len);
 382                 length = -ERANGE;
 383                 goto out;
 384         }
 385
 386         memcpy(buf, canon, len);
 387         length = len;
 388 out:
 389         kfree(canon);
 390         return length;
 391 }
 392
 393 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 394                                      size_t count, loff_t *ppos)
 395 {
 396         char tmpbuf[TMPBUFLEN];
 397         ssize_t length;
 398
 399         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
 400         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 401 }
 402
 403 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 404                                       size_t count, loff_t *ppos)
 405 {
 406         char *page;
 407         ssize_t length;
 408         unsigned int new_value;
 409
 410         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
 411         if (length)
 412                 return length;
 413
 414         if (count >= PAGE_SIZE)
 415                 return -ENOMEM;
 416         if (*ppos != 0) {
 417                 /* No partial writes. */
 418                 return -EINVAL;
 419         }
 420         page = (char *)get_zeroed_page(GFP_KERNEL);
 421         if (!page)
 422                 return -ENOMEM;
 423         length = -EFAULT;
 424         if (copy_from_user(page, buf, count))
 425                 goto out;
 426
 427         length = -EINVAL;
 428         if (sscanf(page, "%u", &new_value) != 1)
 429                 goto out;
 430
 431         selinux_checkreqprot = new_value ? 1 : 0;
 432         length = count;
 433 out:
 434         free_page((unsigned long) page);
 435         return length;
 436 }
 437 static const struct file_operations sel_checkreqprot_ops = {
 438         .read           = sel_read_checkreqprot,
 439         .write          = sel_write_checkreqprot,
 440 };
 441
 442 /*
 443  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 444  */
 445 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 446 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 447 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 448 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 449 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 450
 451 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 452         [SEL_ACCESS] = sel_write_access,
 453         [SEL_CREATE] = sel_write_create,
 454         [SEL_RELABEL] = sel_write_relabel,
 455         [SEL_USER] = sel_write_user,
 456         [SEL_MEMBER] = sel_write_member,
 457         [SEL_CONTEXT] = sel_write_context,
 458 };
 459
 460 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 461 {
 462         ino_t ino = file->f_path.dentry->d_inode->i_ino;
 463         char *data;
 464         ssize_t rv;
 465
 466         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 467                 return -EINVAL;
 468
 469         data = simple_transaction_get(file, buf, size);
 470         if (IS_ERR(data))
 471                 return PTR_ERR(data);
 472
 473         rv = write_op[ino](file, data, size);
 474         if (rv > 0) {
 475                 simple_transaction_set(file, rv);
 476                 rv = size;
 477         }
 478         return rv;
 479 }
 480
 481 static const struct file_operations transaction_ops = {
 482         .write          = selinux_transaction_write,
 483         .read           = simple_transaction_read,
 484         .release        = simple_transaction_release,
 485 };
 486
 487 /*
 488  * payload - write methods
 489  * If the method has a response, the response should be put in buf,
 490  * and the length returned.  Otherwise return 0 or and -error.
 491  */
 492
 493 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 494 {
 495         char *scon, *tcon;
 496         u32 ssid, tsid;
 497         u16 tclass;
 498         struct av_decision avd;
 499         ssize_t length;
 500
 501         length = task_has_security(current, SECURITY__COMPUTE_AV);
 502         if (length)
 503                 return length;
 504
 505         length = -ENOMEM;
 506         scon = kzalloc(size + 1, GFP_KERNEL);
 507         if (!scon)
 508                 return length;
 509
 510         tcon = kzalloc(size + 1, GFP_KERNEL);
 511         if (!tcon)
 512                 goto out;
 513
 514         length = -EINVAL;
 515         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 516                 goto out2;
 517
 518         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 519         if (length < 0)
 520                 goto out2;
 521         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 522         if (length < 0)
 523                 goto out2;
 524
 525         security_compute_av_user(ssid, tsid, tclass, &avd);
 526
 527         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 528                           "%x %x %x %x %u %x",
 529                           avd.allowed, 0xffffffff,
 530                           avd.auditallow, avd.auditdeny,
 531                           avd.seqno, avd.flags);
 532 out2:
 533         kfree(tcon);
 534 out:
 535         kfree(scon);
 536         return length;
 537 }
 538
 539 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 540 {
 541         char *scon, *tcon;
 542         u32 ssid, tsid, newsid;
 543         u16 tclass;
 544         ssize_t length;
 545         char *newcon;
 546         u32 len;
 547
 548         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 549         if (length)
 550                 return length;
 551
 552         length = -ENOMEM;
 553         scon = kzalloc(size + 1, GFP_KERNEL);
 554         if (!scon)
 555                 return length;
 556
 557         tcon = kzalloc(size + 1, GFP_KERNEL);
 558         if (!tcon)
 559                 goto out;
 560
 561         length = -EINVAL;
 562         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 563                 goto out2;
 564
 565         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 566         if (length < 0)
 567                 goto out2;
 568         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 569         if (length < 0)
 570                 goto out2;
 571
 572         length = security_transition_sid_user(ssid, tsid, tclass, &newsid);
 573         if (length < 0)
 574                 goto out2;
 575
 576         length = security_sid_to_context(newsid, &newcon, &len);
 577         if (length < 0)
 578                 goto out2;
 579
 580         if (len > SIMPLE_TRANSACTION_LIMIT) {
 581                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 582                         "payload max\n", __func__, len);
 583                 length = -ERANGE;
 584                 goto out3;
 585         }
 586
 587         memcpy(buf, newcon, len);
 588         length = len;
 589 out3:
 590         kfree(newcon);
 591 out2:
 592         kfree(tcon);
 593 out:
 594         kfree(scon);
 595         return length;
 596 }
 597
 598 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 599 {
 600         char *scon, *tcon;
 601         u32 ssid, tsid, newsid;
 602         u16 tclass;
 603         ssize_t length;
 604         char *newcon;
 605         u32 len;
 606
 607         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 608         if (length)
 609                 return length;
 610
 611         length = -ENOMEM;
 612         scon = kzalloc(size + 1, GFP_KERNEL);
 613         if (!scon)
 614                 return length;
 615
 616         tcon = kzalloc(size + 1, GFP_KERNEL);
 617         if (!tcon)
 618                 goto out;
 619
 620         length = -EINVAL;
 621         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 622                 goto out2;
 623
 624         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 625         if (length < 0)
 626                 goto out2;
 627         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 628         if (length < 0)
 629                 goto out2;
 630
 631         length = security_change_sid(ssid, tsid, tclass, &newsid);
 632         if (length < 0)
 633                 goto out2;
 634
 635         length = security_sid_to_context(newsid, &newcon, &len);
 636         if (length < 0)
 637                 goto out2;
 638
 639         if (len > SIMPLE_TRANSACTION_LIMIT) {
 640                 length = -ERANGE;
 641                 goto out3;
 642         }
 643
 644         memcpy(buf, newcon, len);
 645         length = len;
 646 out3:
 647         kfree(newcon);
 648 out2:
 649         kfree(tcon);
 650 out:
 651         kfree(scon);
 652         return length;
 653 }
 654
 655 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
 656 {
 657         char *con, *user, *ptr;
 658         u32 sid, *sids;
 659         ssize_t length;
 660         char *newcon;
 661         int i, rc;
 662         u32 len, nsids;
 663
 664         length = task_has_security(current, SECURITY__COMPUTE_USER);
 665         if (length)
 666                 return length;
 667
 668         length = -ENOMEM;
 669         con = kzalloc(size + 1, GFP_KERNEL);
 670         if (!con)
 671                 return length;
 672
 673         user = kzalloc(size + 1, GFP_KERNEL);
 674         if (!user)
 675                 goto out;
 676
 677         length = -EINVAL;
 678         if (sscanf(buf, "%s %s", con, user) != 2)
 679                 goto out2;
 680
 681         length = security_context_to_sid(con, strlen(con) + 1, &sid);
 682         if (length < 0)
 683                 goto out2;
 684
 685         length = security_get_user_sids(sid, user, &sids, &nsids);
 686         if (length < 0)
 687                 goto out2;
 688
 689         length = sprintf(buf, "%u", nsids) + 1;
 690         ptr = buf + length;
 691         for (i = 0; i < nsids; i++) {
 692                 rc = security_sid_to_context(sids[i], &newcon, &len);
 693                 if (rc) {
 694                         length = rc;
 695                         goto out3;
 696                 }
 697                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
 698                         kfree(newcon);
 699                         length = -ERANGE;
 700                         goto out3;
 701                 }
 702                 memcpy(ptr, newcon, len);
 703                 kfree(newcon);
 704                 ptr += len;
 705                 length += len;
 706         }
 707 out3:
 708         kfree(sids);
 709 out2:
 710         kfree(user);
 711 out:
 712         kfree(con);
 713         return length;
 714 }
 715
 716 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
 717 {
 718         char *scon, *tcon;
 719         u32 ssid, tsid, newsid;
 720         u16 tclass;
 721         ssize_t length;
 722         char *newcon;
 723         u32 len;
 724
 725         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
 726         if (length)
 727                 return length;
 728
 729         length = -ENOMEM;
 730         scon = kzalloc(size + 1, GFP_KERNEL);
 731         if (!scon)
 732                 return length;
 733
 734         tcon = kzalloc(size + 1, GFP_KERNEL);
 735         if (!tcon)
 736                 goto out;
 737
 738         length = -EINVAL;
 739         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 740                 goto out2;
 741
 742         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 743         if (length < 0)
 744                 goto out2;
 745         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 746         if (length < 0)
 747                 goto out2;
 748
 749         length = security_member_sid(ssid, tsid, tclass, &newsid);
 750         if (length < 0)
 751                 goto out2;
 752
 753         length = security_sid_to_context(newsid, &newcon, &len);
 754         if (length < 0)
 755                 goto out2;
 756
 757         if (len > SIMPLE_TRANSACTION_LIMIT) {
 758                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 759                         "payload max\n", __func__, len);
 760                 length = -ERANGE;
 761                 goto out3;
 762         }
 763
 764         memcpy(buf, newcon, len);
 765         length = len;
 766 out3:
 767         kfree(newcon);
 768 out2:
 769         kfree(tcon);
 770 out:
 771         kfree(scon);
 772         return length;
 773 }
 774
 775 static struct inode *sel_make_inode(struct super_block *sb, int mode)
 776 {
 777         struct inode *ret = new_inode(sb);
 778
 779         if (ret) {
 780                 ret->i_mode = mode;
 781                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
 782         }
 783         return ret;
 784 }
 785
 786 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
 787                              size_t count, loff_t *ppos)
 788 {
 789         char *page = NULL;
 790         ssize_t length;
 791         ssize_t ret;
 792         int cur_enforcing;
 793         struct inode *inode = filep->f_path.dentry->d_inode;
 794         unsigned index = inode->i_ino & SEL_INO_MASK;
 795         const char *name = filep->f_path.dentry->d_name.name;
 796
 797         mutex_lock(&sel_mutex);
 798
 799         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
 800                 ret = -EINVAL;
 801                 goto out;
 802         }
 803
 804         page = (char *)get_zeroed_page(GFP_KERNEL);
 805         if (!page) {
 806                 ret = -ENOMEM;
 807                 goto out;
 808         }
 809
 810         cur_enforcing = security_get_bool_value(index);
 811         if (cur_enforcing < 0) {
 812                 ret = cur_enforcing;
 813                 goto out;
 814         }
 815         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
 816                           bool_pending_values[index]);
 817         ret = simple_read_from_buffer(buf, count, ppos, page, length);
 818 out:
 819         mutex_unlock(&sel_mutex);
 820         if (page)
 821                 free_page((unsigned long)page);
 822         return ret;
 823 }
 824
 825 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
 826                               size_t count, loff_t *ppos)
 827 {
 828         char *page = NULL;
 829         ssize_t length;
 830         int new_value;
 831         struct inode *inode = filep->f_path.dentry->d_inode;
 832         unsigned index = inode->i_ino & SEL_INO_MASK;
 833         const char *name = filep->f_path.dentry->d_name.name;
 834
 835         mutex_lock(&sel_mutex);
 836
 837         length = task_has_security(current, SECURITY__SETBOOL);
 838         if (length)
 839                 goto out;
 840
 841         if (index >= bool_num || strcmp(name, bool_pending_names[index])) {
 842                 length = -EINVAL;
 843                 goto out;
 844         }
 845
 846         if (count >= PAGE_SIZE) {
 847                 length = -ENOMEM;
 848                 goto out;
 849         }
 850
 851         if (*ppos != 0) {
 852                 /* No partial writes. */
 853                 length = -EINVAL;
 854                 goto out;
 855         }
 856         page = (char *)get_zeroed_page(GFP_KERNEL);
 857         if (!page) {
 858                 length = -ENOMEM;
 859                 goto out;
 860         }
 861
 862         length = -EFAULT;
 863         if (copy_from_user(page, buf, count))
 864                 goto out;
 865
 866         length = -EINVAL;
 867         if (sscanf(page, "%d", &new_value) != 1)
 868                 goto out;
 869
 870         if (new_value)
 871                 new_value = 1;
 872
 873         bool_pending_values[index] = new_value;
 874         length = count;
 875
 876 out:
 877         mutex_unlock(&sel_mutex);
 878         if (page)
 879                 free_page((unsigned long) page);
 880         return length;
 881 }
 882
 883 static const struct file_operations sel_bool_ops = {
 884         .read           = sel_read_bool,
 885         .write          = sel_write_bool,
 886 };
 887
 888 static ssize_t sel_commit_bools_write(struct file *filep,
 889                                       const char __user *buf,
 890                                       size_t count, loff_t *ppos)
 891 {
 892         char *page = NULL;
 893         ssize_t length;
 894         int new_value;
 895
 896         mutex_lock(&sel_mutex);
 897
 898         length = task_has_security(current, SECURITY__SETBOOL);
 899         if (length)
 900                 goto out;
 901
 902         if (count >= PAGE_SIZE) {
 903                 length = -ENOMEM;
 904                 goto out;
 905         }
 906         if (*ppos != 0) {
 907                 /* No partial writes. */
 908                 goto out;
 909         }
 910         page = (char *)get_zeroed_page(GFP_KERNEL);
 911         if (!page) {
 912                 length = -ENOMEM;
 913                 goto out;
 914         }
 915
 916         length = -EFAULT;
 917         if (copy_from_user(page, buf, count))
 918                 goto out;
 919
 920         length = -EINVAL;
 921         if (sscanf(page, "%d", &new_value) != 1)
 922                 goto out;
 923
 924         if (new_value && bool_pending_values)
 925                 security_set_bools(bool_num, bool_pending_values);
 926
 927         length = count;
 928
 929 out:
 930         mutex_unlock(&sel_mutex);
 931         if (page)
 932                 free_page((unsigned long) page);
 933         return length;
 934 }
 935
 936 static const struct file_operations sel_commit_bools_ops = {
 937         .write          = sel_commit_bools_write,
 938 };
 939
 940 static void sel_remove_entries(struct dentry *de)
 941 {
 942         struct list_head *node;
 943
 944         spin_lock(&dcache_lock);
 945         node = de->d_subdirs.next;
 946         while (node != &de->d_subdirs) {
 947                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
 948                 list_del_init(node);
 949
 950                 if (d->d_inode) {
 951                         d = dget_locked(d);
 952                         spin_unlock(&dcache_lock);
 953                         d_delete(d);
 954                         simple_unlink(de->d_inode, d);
 955                         dput(d);
 956                         spin_lock(&dcache_lock);
 957                 }
 958                 node = de->d_subdirs.next;
 959         }
 960
 961         spin_unlock(&dcache_lock);
 962 }
 963
 964 #define BOOL_DIR_NAME "booleans"
 965
 966 static int sel_make_bools(void)
 967 {
 968         int i, ret = 0;
 969         ssize_t len;
 970         struct dentry *dentry = NULL;
 971         struct dentry *dir = bool_dir;
 972         struct inode *inode = NULL;
 973         struct inode_security_struct *isec;
 974         char **names = NULL, *page;
 975         int num;
 976         int *values = NULL;
 977         u32 sid;
 978
 979         /* remove any existing files */
 980         for (i = 0; i < bool_num; i++)
 981                 kfree(bool_pending_names[i]);
 982         kfree(bool_pending_names);
 983         kfree(bool_pending_values);
 984         bool_pending_names = NULL;
 985         bool_pending_values = NULL;
 986
 987         sel_remove_entries(dir);
 988
 989         page = (char *)get_zeroed_page(GFP_KERNEL);
 990         if (!page)
 991                 return -ENOMEM;
 992
 993         ret = security_get_bools(&num, &names, &values);
 994         if (ret != 0)
 995                 goto out;
 996
 997         for (i = 0; i < num; i++) {
 998                 dentry = d_alloc_name(dir, names[i]);
 999                 if (!dentry) {
1000                         ret = -ENOMEM;
1001                         goto err;
1002                 }
1003                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1004                 if (!inode) {
1005                         ret = -ENOMEM;
1006                         goto err;
1007                 }
1008
1009                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1010                 if (len < 0) {
1011                         ret = -EINVAL;
1012                         goto err;
1013                 } else if (len >= PAGE_SIZE) {
1014                         ret = -ENAMETOOLONG;
1015                         goto err;
1016                 }
1017                 isec = (struct inode_security_struct *)inode->i_security;
1018                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1019                 if (ret)
1020                         goto err;
1021                 isec->sid = sid;
1022                 isec->initialized = 1;
1023                 inode->i_fop = &sel_bool_ops;
1024                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1025                 d_add(dentry, inode);
1026         }
1027         bool_num = num;
1028         bool_pending_names = names;
1029         bool_pending_values = values;
1030 out:
1031         free_page((unsigned long)page);
1032         return ret;
1033 err:
1034         if (names) {
1035                 for (i = 0; i < num; i++)
1036                         kfree(names[i]);
1037                 kfree(names);
1038         }
1039         kfree(values);
1040         sel_remove_entries(dir);
1041         ret = -ENOMEM;
1042         goto out;
1043 }
1044
1045 #define NULL_FILE_NAME "null"
1046
1047 struct dentry *selinux_null;
1048
1049 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1050                                             size_t count, loff_t *ppos)
1051 {
1052         char tmpbuf[TMPBUFLEN];
1053         ssize_t length;
1054
1055         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1056         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1057 }
1058
1059 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1060                                              const char __user *buf,
1061                                              size_t count, loff_t *ppos)
1062
1063 {
1064         char *page;
1065         ssize_t ret;
1066         int new_value;
1067
1068         if (count >= PAGE_SIZE) {
1069                 ret = -ENOMEM;
1070                 goto out;
1071         }
1072
1073         if (*ppos != 0) {
1074                 /* No partial writes. */
1075                 ret = -EINVAL;
1076                 goto out;
1077         }
1078
1079         page = (char *)get_zeroed_page(GFP_KERNEL);
1080         if (!page) {
1081                 ret = -ENOMEM;
1082                 goto out;
1083         }
1084
1085         if (copy_from_user(page, buf, count)) {
1086                 ret = -EFAULT;
1087                 goto out_free;
1088         }
1089
1090         if (sscanf(page, "%u", &new_value) != 1) {
1091                 ret = -EINVAL;
1092                 goto out;
1093         }
1094
1095         if (new_value != avc_cache_threshold) {
1096                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1097                 if (ret)
1098                         goto out_free;
1099                 avc_cache_threshold = new_value;
1100         }
1101         ret = count;
1102 out_free:
1103         free_page((unsigned long)page);
1104 out:
1105         return ret;
1106 }
1107
1108 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1109                                        size_t count, loff_t *ppos)
1110 {
1111         char *page;
1112         ssize_t ret = 0;
1113
1114         page = (char *)__get_free_page(GFP_KERNEL);
1115         if (!page) {
1116                 ret = -ENOMEM;
1117                 goto out;
1118         }
1119         ret = avc_get_hash_stats(page);
1120         if (ret >= 0)
1121                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1122         free_page((unsigned long)page);
1123 out:
1124         return ret;
1125 }
1126
1127 static const struct file_operations sel_avc_cache_threshold_ops = {
1128         .read           = sel_read_avc_cache_threshold,
1129         .write          = sel_write_avc_cache_threshold,
1130 };
1131
1132 static const struct file_operations sel_avc_hash_stats_ops = {
1133         .read           = sel_read_avc_hash_stats,
1134 };
1135
1136 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1137 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1138 {
1139         int cpu;
1140
1141         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1142                 if (!cpu_possible(cpu))
1143                         continue;
1144                 *idx = cpu + 1;
1145                 return &per_cpu(avc_cache_stats, cpu);
1146         }
1147         return NULL;
1148 }
1149
1150 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1151 {
1152         loff_t n = *pos - 1;
1153
1154         if (*pos == 0)
1155                 return SEQ_START_TOKEN;
1156
1157         return sel_avc_get_stat_idx(&n);
1158 }
1159
1160 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1161 {
1162         return sel_avc_get_stat_idx(pos);
1163 }
1164
1165 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1166 {
1167         struct avc_cache_stats *st = v;
1168
1169         if (v == SEQ_START_TOKEN)
1170                 seq_printf(seq, "lookups hits misses allocations reclaims "
1171                            "frees\n");
1172         else
1173                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1174                            st->hits, st->misses, st->allocations,
1175                            st->reclaims, st->frees);
1176         return 0;
1177 }
1178
1179 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1180 { }
1181
1182 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1183         .start          = sel_avc_stats_seq_start,
1184         .next           = sel_avc_stats_seq_next,
1185         .show           = sel_avc_stats_seq_show,
1186         .stop           = sel_avc_stats_seq_stop,
1187 };
1188
1189 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1190 {
1191         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1192 }
1193
1194 static const struct file_operations sel_avc_cache_stats_ops = {
1195         .open           = sel_open_avc_cache_stats,
1196         .read           = seq_read,
1197         .llseek         = seq_lseek,
1198         .release        = seq_release,
1199 };
1200 #endif
1201
1202 static int sel_make_avc_files(struct dentry *dir)
1203 {
1204         int i, ret = 0;
1205         static struct tree_descr files[] = {
1206                 { "cache_threshold",
1207                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1208                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1209 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1210                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1211 #endif
1212         };
1213
1214         for (i = 0; i < ARRAY_SIZE(files); i++) {
1215                 struct inode *inode;
1216                 struct dentry *dentry;
1217
1218                 dentry = d_alloc_name(dir, files[i].name);
1219                 if (!dentry) {
1220                         ret = -ENOMEM;
1221                         goto out;
1222                 }
1223
1224                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1225                 if (!inode) {
1226                         ret = -ENOMEM;
1227                         goto out;
1228                 }
1229                 inode->i_fop = files[i].ops;
1230                 inode->i_ino = ++sel_last_ino;
1231                 d_add(dentry, inode);
1232         }
1233 out:
1234         return ret;
1235 }
1236
1237 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1238                                 size_t count, loff_t *ppos)
1239 {
1240         struct inode *inode;
1241         char *con;
1242         u32 sid, len;
1243         ssize_t ret;
1244
1245         inode = file->f_path.dentry->d_inode;
1246         sid = inode->i_ino&SEL_INO_MASK;
1247         ret = security_sid_to_context(sid, &con, &len);
1248         if (ret < 0)
1249                 return ret;
1250
1251         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1252         kfree(con);
1253         return ret;
1254 }
1255
1256 static const struct file_operations sel_initcon_ops = {
1257         .read           = sel_read_initcon,
1258 };
1259
1260 static int sel_make_initcon_files(struct dentry *dir)
1261 {
1262         int i, ret = 0;
1263
1264         for (i = 1; i <= SECINITSID_NUM; i++) {
1265                 struct inode *inode;
1266                 struct dentry *dentry;
1267                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1268                 if (!dentry) {
1269                         ret = -ENOMEM;
1270                         goto out;
1271                 }
1272
1273                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1274                 if (!inode) {
1275                         ret = -ENOMEM;
1276                         goto out;
1277                 }
1278                 inode->i_fop = &sel_initcon_ops;
1279                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1280                 d_add(dentry, inode);
1281         }
1282 out:
1283         return ret;
1284 }
1285
1286 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1287 {
1288         return a / b - (a % b < 0);
1289 }
1290
1291 static inline unsigned long sel_class_to_ino(u16 class)
1292 {
1293         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1294 }
1295
1296 static inline u16 sel_ino_to_class(unsigned long ino)
1297 {
1298         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1299 }
1300
1301 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1302 {
1303         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1304 }
1305
1306 static inline u32 sel_ino_to_perm(unsigned long ino)
1307 {
1308         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1309 }
1310
1311 static ssize_t sel_read_class(struct file *file, char __user *buf,
1312                                 size_t count, loff_t *ppos)
1313 {
1314         ssize_t rc, len;
1315         char *page;
1316         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1317
1318         page = (char *)__get_free_page(GFP_KERNEL);
1319         if (!page) {
1320                 rc = -ENOMEM;
1321                 goto out;
1322         }
1323
1324         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1325         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1326         free_page((unsigned long)page);
1327 out:
1328         return rc;
1329 }
1330
1331 static const struct file_operations sel_class_ops = {
1332         .read           = sel_read_class,
1333 };
1334
1335 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1336                                 size_t count, loff_t *ppos)
1337 {
1338         ssize_t rc, len;
1339         char *page;
1340         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1341
1342         page = (char *)__get_free_page(GFP_KERNEL);
1343         if (!page) {
1344                 rc = -ENOMEM;
1345                 goto out;
1346         }
1347
1348         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1349         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1350         free_page((unsigned long)page);
1351 out:
1352         return rc;
1353 }
1354
1355 static const struct file_operations sel_perm_ops = {
1356         .read           = sel_read_perm,
1357 };
1358
1359 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1360                                   size_t count, loff_t *ppos)
1361 {
1362         int value;
1363         char tmpbuf[TMPBUFLEN];
1364         ssize_t length;
1365         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1366
1367         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1368         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1369
1370         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1371 }
1372
1373 static const struct file_operations sel_policycap_ops = {
1374         .read           = sel_read_policycap,
1375 };
1376
1377 static int sel_make_perm_files(char *objclass, int classvalue,
1378                                 struct dentry *dir)
1379 {
1380         int i, rc = 0, nperms;
1381         char **perms;
1382
1383         rc = security_get_permissions(objclass, &perms, &nperms);
1384         if (rc)
1385                 goto out;
1386
1387         for (i = 0; i < nperms; i++) {
1388                 struct inode *inode;
1389                 struct dentry *dentry;
1390
1391                 dentry = d_alloc_name(dir, perms[i]);
1392                 if (!dentry) {
1393                         rc = -ENOMEM;
1394                         goto out1;
1395                 }
1396
1397                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1398                 if (!inode) {
1399                         rc = -ENOMEM;
1400                         goto out1;
1401                 }
1402                 inode->i_fop = &sel_perm_ops;
1403                 /* i+1 since perm values are 1-indexed */
1404                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1405                 d_add(dentry, inode);
1406         }
1407
1408 out1:
1409         for (i = 0; i < nperms; i++)
1410                 kfree(perms[i]);
1411         kfree(perms);
1412 out:
1413         return rc;
1414 }
1415
1416 static int sel_make_class_dir_entries(char *classname, int index,
1417                                         struct dentry *dir)
1418 {
1419         struct dentry *dentry = NULL;
1420         struct inode *inode = NULL;
1421         int rc;
1422
1423         dentry = d_alloc_name(dir, "index");
1424         if (!dentry) {
1425                 rc = -ENOMEM;
1426                 goto out;
1427         }
1428
1429         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1430         if (!inode) {
1431                 rc = -ENOMEM;
1432                 goto out;
1433         }
1434
1435         inode->i_fop = &sel_class_ops;
1436         inode->i_ino = sel_class_to_ino(index);
1437         d_add(dentry, inode);
1438
1439         dentry = d_alloc_name(dir, "perms");
1440         if (!dentry) {
1441                 rc = -ENOMEM;
1442                 goto out;
1443         }
1444
1445         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1446         if (rc)
1447                 goto out;
1448
1449         rc = sel_make_perm_files(classname, index, dentry);
1450
1451 out:
1452         return rc;
1453 }
1454
1455 static void sel_remove_classes(void)
1456 {
1457         struct list_head *class_node;
1458
1459         list_for_each(class_node, &class_dir->d_subdirs) {
1460                 struct dentry *class_subdir = list_entry(class_node,
1461                                         struct dentry, d_u.d_child);
1462                 struct list_head *class_subdir_node;
1463
1464                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1465                         struct dentry *d = list_entry(class_subdir_node,
1466                                                 struct dentry, d_u.d_child);
1467
1468                         if (d->d_inode)
1469                                 if (d->d_inode->i_mode & S_IFDIR)
1470                                         sel_remove_entries(d);
1471                 }
1472
1473                 sel_remove_entries(class_subdir);
1474         }
1475
1476         sel_remove_entries(class_dir);
1477 }
1478
1479 static int sel_make_classes(void)
1480 {
1481         int rc = 0, nclasses, i;
1482         char **classes;
1483
1484         /* delete any existing entries */
1485         sel_remove_classes();
1486
1487         rc = security_get_classes(&classes, &nclasses);
1488         if (rc < 0)
1489                 goto out;
1490
1491         /* +2 since classes are 1-indexed */
1492         last_class_ino = sel_class_to_ino(nclasses + 2);
1493
1494         for (i = 0; i < nclasses; i++) {
1495                 struct dentry *class_name_dir;
1496
1497                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1498                 if (!class_name_dir) {
1499                         rc = -ENOMEM;
1500                         goto out1;
1501                 }
1502
1503                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1504                                 &last_class_ino);
1505                 if (rc)
1506                         goto out1;
1507
1508                 /* i+1 since class values are 1-indexed */
1509                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1510                                 class_name_dir);
1511                 if (rc)
1512                         goto out1;
1513         }
1514
1515 out1:
1516         for (i = 0; i < nclasses; i++)
1517                 kfree(classes[i]);
1518         kfree(classes);
1519 out:
1520         return rc;
1521 }
1522
1523 static int sel_make_policycap(void)
1524 {
1525         unsigned int iter;
1526         struct dentry *dentry = NULL;
1527         struct inode *inode = NULL;
1528
1529         sel_remove_entries(policycap_dir);
1530
1531         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1532                 if (iter < ARRAY_SIZE(policycap_names))
1533                         dentry = d_alloc_name(policycap_dir,
1534                                               policycap_names[iter]);
1535                 else
1536                         dentry = d_alloc_name(policycap_dir, "unknown");
1537
1538                 if (dentry == NULL)
1539                         return -ENOMEM;
1540
1541                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1542                 if (inode == NULL)
1543                         return -ENOMEM;
1544
1545                 inode->i_fop = &sel_policycap_ops;
1546                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1547                 d_add(dentry, inode);
1548         }
1549
1550         return 0;
1551 }
1552
1553 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1554                         unsigned long *ino)
1555 {
1556         int ret = 0;
1557         struct inode *inode;
1558
1559         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1560         if (!inode) {
1561                 ret = -ENOMEM;
1562                 goto out;
1563         }
1564         inode->i_op = &simple_dir_inode_operations;
1565         inode->i_fop = &simple_dir_operations;
1566         inode->i_ino = ++(*ino);
1567         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1568         inc_nlink(inode);
1569         d_add(dentry, inode);
1570         /* bump link count on parent directory, too */
1571         inc_nlink(dir);
1572 out:
1573         return ret;
1574 }
1575
1576 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1577 {
1578         int ret;
1579         struct dentry *dentry;
1580         struct inode *inode, *root_inode;
1581         struct inode_security_struct *isec;
1582
1583         static struct tree_descr selinux_files[] = {
1584                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1585                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1586                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1587                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1588                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1589                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1590                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1591                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1592                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1593                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1594                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1595                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1596                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1597                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1598                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1599                 /* last one */ {""}
1600         };
1601         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1602         if (ret)
1603                 goto err;
1604
1605         root_inode = sb->s_root->d_inode;
1606
1607         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1608         if (!dentry) {
1609                 ret = -ENOMEM;
1610                 goto err;
1611         }
1612
1613         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1614         if (ret)
1615                 goto err;
1616
1617         bool_dir = dentry;
1618
1619         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1620         if (!dentry) {
1621                 ret = -ENOMEM;
1622                 goto err;
1623         }
1624
1625         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1626         if (!inode) {
1627                 ret = -ENOMEM;
1628                 goto err;
1629         }
1630         inode->i_ino = ++sel_last_ino;
1631         isec = (struct inode_security_struct *)inode->i_security;
1632         isec->sid = SECINITSID_DEVNULL;
1633         isec->sclass = SECCLASS_CHR_FILE;
1634         isec->initialized = 1;
1635
1636         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1637         d_add(dentry, inode);
1638         selinux_null = dentry;
1639
1640         dentry = d_alloc_name(sb->s_root, "avc");
1641         if (!dentry) {
1642                 ret = -ENOMEM;
1643                 goto err;
1644         }
1645
1646         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1647         if (ret)
1648                 goto err;
1649
1650         ret = sel_make_avc_files(dentry);
1651         if (ret)
1652                 goto err;
1653
1654         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1655         if (!dentry) {
1656                 ret = -ENOMEM;
1657                 goto err;
1658         }
1659
1660         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1661         if (ret)
1662                 goto err;
1663
1664         ret = sel_make_initcon_files(dentry);
1665         if (ret)
1666                 goto err;
1667
1668         dentry = d_alloc_name(sb->s_root, "class");
1669         if (!dentry) {
1670                 ret = -ENOMEM;
1671                 goto err;
1672         }
1673
1674         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1675         if (ret)
1676                 goto err;
1677
1678         class_dir = dentry;
1679
1680         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1681         if (!dentry) {
1682                 ret = -ENOMEM;
1683                 goto err;
1684         }
1685
1686         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1687         if (ret)
1688                 goto err;
1689
1690         policycap_dir = dentry;
1691
1692 out:
1693         return ret;
1694 err:
1695         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1696                 __func__);
1697         goto out;
1698 }
1699
1700 static int sel_get_sb(struct file_system_type *fs_type,
1701                       int flags, const char *dev_name, void *data,
1702                       struct vfsmount *mnt)
1703 {
1704         return get_sb_single(fs_type, flags, data, sel_fill_super, mnt);
1705 }
1706
1707 static struct file_system_type sel_fs_type = {
1708         .name           = "selinuxfs",
1709         .get_sb         = sel_get_sb,
1710         .kill_sb        = kill_litter_super,
1711 };
1712
1713 struct vfsmount *selinuxfs_mount;
1714
1715 static int __init init_sel_fs(void)
1716 {
1717         int err;
1718
1719         if (!selinux_enabled)
1720                 return 0;
1721         err = register_filesystem(&sel_fs_type);
1722         if (!err) {
1723                 selinuxfs_mount = kern_mount(&sel_fs_type);
1724                 if (IS_ERR(selinuxfs_mount)) {
1725                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1726                         err = PTR_ERR(selinuxfs_mount);
1727                         selinuxfs_mount = NULL;
1728                 }
1729         }
1730         return err;
1731 }
1732
1733 __initcall(init_sel_fs);
1734
1735 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1736 void exit_sel_fs(void)
1737 {
1738         unregister_filesystem(&sel_fs_type);
1739 }
1740 #endif