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 #include <linux/kobject.h>
  32 #include <linux/ctype.h>
  33
  34 /* selinuxfs pseudo filesystem for exporting the security policy API.
  35    Based on the proc code and the fs/nfsd/nfsctl.c code. */
  36
  37 #include "flask.h"
  38 #include "avc.h"
  39 #include "avc_ss.h"
  40 #include "security.h"
  41 #include "objsec.h"
  42 #include "conditional.h"
  43
  44 /* Policy capability filenames */
  45 static char *policycap_names[] = {
  46         "network_peer_controls",
  47         "open_perms"
  48 };
  49
  50 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
  51
  52 static int __init checkreqprot_setup(char *str)
  53 {
  54         unsigned long checkreqprot;
  55         if (!strict_strtoul(str, 0, &checkreqprot))
  56                 selinux_checkreqprot = checkreqprot ? 1 : 0;
  57         return 1;
  58 }
  59 __setup("checkreqprot=", checkreqprot_setup);
  60
  61 static DEFINE_MUTEX(sel_mutex);
  62
  63 /* global data for booleans */
  64 static struct dentry *bool_dir;
  65 static int bool_num;
  66 static char **bool_pending_names;
  67 static int *bool_pending_values;
  68
  69 /* global data for classes */
  70 static struct dentry *class_dir;
  71 static unsigned long last_class_ino;
  72
  73 static char policy_opened;
  74
  75 /* global data for policy capabilities */
  76 static struct dentry *policycap_dir;
  77
  78 extern void selnl_notify_setenforce(int val);
  79
  80 /* Check whether a task is allowed to use a security operation. */
  81 static int task_has_security(struct task_struct *tsk,
  82                              u32 perms)
  83 {
  84         const struct task_security_struct *tsec;
  85         u32 sid = 0;
  86
  87         rcu_read_lock();
  88         tsec = __task_cred(tsk)->security;
  89         if (tsec)
  90                 sid = tsec->sid;
  91         rcu_read_unlock();
  92         if (!tsec)
  93                 return -EACCES;
  94
  95         return avc_has_perm(sid, SECINITSID_SECURITY,
  96                             SECCLASS_SECURITY, perms, NULL);
  97 }
  98
  99 enum sel_inos {
 100         SEL_ROOT_INO = 2,
 101         SEL_LOAD,       /* load policy */
 102         SEL_ENFORCE,    /* get or set enforcing status */
 103         SEL_CONTEXT,    /* validate context */
 104         SEL_ACCESS,     /* compute access decision */
 105         SEL_CREATE,     /* compute create labeling decision */
 106         SEL_RELABEL,    /* compute relabeling decision */
 107         SEL_USER,       /* compute reachable user contexts */
 108         SEL_POLICYVERS, /* return policy version for this kernel */
 109         SEL_COMMIT_BOOLS, /* commit new boolean values */
 110         SEL_MLS,        /* return if MLS policy is enabled */
 111         SEL_DISABLE,    /* disable SELinux until next reboot */
 112         SEL_MEMBER,     /* compute polyinstantiation membership decision */
 113         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
 114         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
 115         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
 116         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
 117         SEL_STATUS,     /* export current status using mmap() */
 118         SEL_POLICY,     /* allow userspace to read the in kernel policy */
 119         SEL_INO_NEXT,   /* The next inode number to use */
 120 };
 121
 122 static unsigned long sel_last_ino = SEL_INO_NEXT - 1;
 123
 124 #define SEL_INITCON_INO_OFFSET          0x01000000
 125 #define SEL_BOOL_INO_OFFSET             0x02000000
 126 #define SEL_CLASS_INO_OFFSET            0x04000000
 127 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
 128 #define SEL_INO_MASK                    0x00ffffff
 129
 130 #define TMPBUFLEN       12
 131 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 132                                 size_t count, loff_t *ppos)
 133 {
 134         char tmpbuf[TMPBUFLEN];
 135         ssize_t length;
 136
 137         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
 138         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 139 }
 140
 141 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 142 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 143                                  size_t count, loff_t *ppos)
 144
 145 {
 146         char *page = NULL;
 147         ssize_t length;
 148         int new_value;
 149
 150         length = -ENOMEM;
 151         if (count >= PAGE_SIZE)
 152                 goto out;
 153
 154         /* No partial writes. */
 155         length = EINVAL;
 156         if (*ppos != 0)
 157                 goto out;
 158
 159         length = -ENOMEM;
 160         page = (char *)get_zeroed_page(GFP_KERNEL);
 161         if (!page)
 162                 goto out;
 163
 164         length = -EFAULT;
 165         if (copy_from_user(page, buf, count))
 166                 goto out;
 167
 168         length = -EINVAL;
 169         if (sscanf(page, "%d", &new_value) != 1)
 170                 goto out;
 171
 172         if (new_value != selinux_enforcing) {
 173                 length = task_has_security(current, SECURITY__SETENFORCE);
 174                 if (length)
 175                         goto out;
 176                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 177                         "enforcing=%d old_enforcing=%d auid=%u ses=%u",
 178                         new_value, selinux_enforcing,
 179                         audit_get_loginuid(current),
 180                         audit_get_sessionid(current));
 181                 selinux_enforcing = new_value;
 182                 if (selinux_enforcing)
 183                         avc_ss_reset(0);
 184                 selnl_notify_setenforce(selinux_enforcing);
 185                 selinux_status_update_setenforce(selinux_enforcing);
 186         }
 187         length = count;
 188 out:
 189         free_page((unsigned long) page);
 190         return length;
 191 }
 192 #else
 193 #define sel_write_enforce NULL
 194 #endif
 195
 196 static const struct file_operations sel_enforce_ops = {
 197         .read           = sel_read_enforce,
 198         .write          = sel_write_enforce,
 199         .llseek         = generic_file_llseek,
 200 };
 201
 202 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 203                                         size_t count, loff_t *ppos)
 204 {
 205         char tmpbuf[TMPBUFLEN];
 206         ssize_t length;
 207         ino_t ino = filp->f_path.dentry->d_inode->i_ino;
 208         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 209                 security_get_reject_unknown() : !security_get_allow_unknown();
 210
 211         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 212         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 213 }
 214
 215 static const struct file_operations sel_handle_unknown_ops = {
 216         .read           = sel_read_handle_unknown,
 217         .llseek         = generic_file_llseek,
 218 };
 219
 220 static int sel_open_handle_status(struct inode *inode, struct file *filp)
 221 {
 222         struct page    *status = selinux_kernel_status_page();
 223
 224         if (!status)
 225                 return -ENOMEM;
 226
 227         filp->private_data = status;
 228
 229         return 0;
 230 }
 231
 232 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 233                                       size_t count, loff_t *ppos)
 234 {
 235         struct page    *status = filp->private_data;
 236
 237         BUG_ON(!status);
 238
 239         return simple_read_from_buffer(buf, count, ppos,
 240                                        page_address(status),
 241                                        sizeof(struct selinux_kernel_status));
 242 }
 243
 244 static int sel_mmap_handle_status(struct file *filp,
 245                                   struct vm_area_struct *vma)
 246 {
 247         struct page    *status = filp->private_data;
 248         unsigned long   size = vma->vm_end - vma->vm_start;
 249
 250         BUG_ON(!status);
 251
 252         /* only allows one page from the head */
 253         if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 254                 return -EIO;
 255         /* disallow writable mapping */
 256         if (vma->vm_flags & VM_WRITE)
 257                 return -EPERM;
 258         /* disallow mprotect() turns it into writable */
 259         vma->vm_flags &= ~VM_MAYWRITE;
 260
 261         return remap_pfn_range(vma, vma->vm_start,
 262                                page_to_pfn(status),
 263                                size, vma->vm_page_prot);
 264 }
 265
 266 static const struct file_operations sel_handle_status_ops = {
 267         .open           = sel_open_handle_status,
 268         .read           = sel_read_handle_status,
 269         .mmap           = sel_mmap_handle_status,
 270         .llseek         = generic_file_llseek,
 271 };
 272
 273 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 274 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 275                                  size_t count, loff_t *ppos)
 276
 277 {
 278         char *page = NULL;
 279         ssize_t length;
 280         int new_value;
 281         extern int selinux_disable(void);
 282
 283         length = -ENOMEM;
 284         if (count >= PAGE_SIZE)
 285                 goto out;;
 286
 287         /* No partial writes. */
 288         length = -EINVAL;
 289         if (*ppos != 0)
 290                 goto out;
 291
 292         length = -ENOMEM;
 293         page = (char *)get_zeroed_page(GFP_KERNEL);
 294         if (!page)
 295                 goto out;
 296
 297         length = -EFAULT;
 298         if (copy_from_user(page, buf, count))
 299                 goto out;
 300
 301         length = -EINVAL;
 302         if (sscanf(page, "%d", &new_value) != 1)
 303                 goto out;
 304
 305         if (new_value) {
 306                 length = selinux_disable();
 307                 if (length)
 308                         goto out;
 309                 audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
 310                         "selinux=0 auid=%u ses=%u",
 311                         audit_get_loginuid(current),
 312                         audit_get_sessionid(current));
 313         }
 314
 315         length = count;
 316 out:
 317         free_page((unsigned long) page);
 318         return length;
 319 }
 320 #else
 321 #define sel_write_disable NULL
 322 #endif
 323
 324 static const struct file_operations sel_disable_ops = {
 325         .write          = sel_write_disable,
 326         .llseek         = generic_file_llseek,
 327 };
 328
 329 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 330                                    size_t count, loff_t *ppos)
 331 {
 332         char tmpbuf[TMPBUFLEN];
 333         ssize_t length;
 334
 335         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 336         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 337 }
 338
 339 static const struct file_operations sel_policyvers_ops = {
 340         .read           = sel_read_policyvers,
 341         .llseek         = generic_file_llseek,
 342 };
 343
 344 /* declaration for sel_write_load */
 345 static int sel_make_bools(void);
 346 static int sel_make_classes(void);
 347 static int sel_make_policycap(void);
 348
 349 /* declaration for sel_make_class_dirs */
 350 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
 351                         unsigned long *ino);
 352
 353 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 354                                 size_t count, loff_t *ppos)
 355 {
 356         char tmpbuf[TMPBUFLEN];
 357         ssize_t length;
 358
 359         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 360                            security_mls_enabled());
 361         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 362 }
 363
 364 static const struct file_operations sel_mls_ops = {
 365         .read           = sel_read_mls,
 366         .llseek         = generic_file_llseek,
 367 };
 368
 369 struct policy_load_memory {
 370         size_t len;
 371         void *data;
 372 };
 373
 374 static int sel_open_policy(struct inode *inode, struct file *filp)
 375 {
 376         struct policy_load_memory *plm = NULL;
 377         int rc;
 378
 379         BUG_ON(filp->private_data);
 380
 381         mutex_lock(&sel_mutex);
 382
 383         rc = task_has_security(current, SECURITY__READ_POLICY);
 384         if (rc)
 385                 goto err;
 386
 387         rc = -EBUSY;
 388         if (policy_opened)
 389                 goto err;
 390
 391         rc = -ENOMEM;
 392         plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 393         if (!plm)
 394                 goto err;
 395
 396         if (i_size_read(inode) != security_policydb_len()) {
 397                 mutex_lock(&inode->i_mutex);
 398                 i_size_write(inode, security_policydb_len());
 399                 mutex_unlock(&inode->i_mutex);
 400         }
 401
 402         rc = security_read_policy(&plm->data, &plm->len);
 403         if (rc)
 404                 goto err;
 405
 406         policy_opened = 1;
 407
 408         filp->private_data = plm;
 409
 410         mutex_unlock(&sel_mutex);
 411
 412         return 0;
 413 err:
 414         mutex_unlock(&sel_mutex);
 415
 416         if (plm)
 417                 vfree(plm->data);
 418         kfree(plm);
 419         return rc;
 420 }
 421
 422 static int sel_release_policy(struct inode *inode, struct file *filp)
 423 {
 424         struct policy_load_memory *plm = filp->private_data;
 425
 426         BUG_ON(!plm);
 427
 428         policy_opened = 0;
 429
 430         vfree(plm->data);
 431         kfree(plm);
 432
 433         return 0;
 434 }
 435
 436 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 437                                size_t count, loff_t *ppos)
 438 {
 439         struct policy_load_memory *plm = filp->private_data;
 440         int ret;
 441
 442         mutex_lock(&sel_mutex);
 443
 444         ret = task_has_security(current, SECURITY__READ_POLICY);
 445         if (ret)
 446                 goto out;
 447
 448         ret = simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 449 out:
 450         mutex_unlock(&sel_mutex);
 451         return ret;
 452 }
 453
 454 static int sel_mmap_policy_fault(struct vm_area_struct *vma,
 455                                  struct vm_fault *vmf)
 456 {
 457         struct policy_load_memory *plm = vma->vm_file->private_data;
 458         unsigned long offset;
 459         struct page *page;
 460
 461         if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 462                 return VM_FAULT_SIGBUS;
 463
 464         offset = vmf->pgoff << PAGE_SHIFT;
 465         if (offset >= roundup(plm->len, PAGE_SIZE))
 466                 return VM_FAULT_SIGBUS;
 467
 468         page = vmalloc_to_page(plm->data + offset);
 469         get_page(page);
 470
 471         vmf->page = page;
 472
 473         return 0;
 474 }
 475
 476 static struct vm_operations_struct sel_mmap_policy_ops = {
 477         .fault = sel_mmap_policy_fault,
 478         .page_mkwrite = sel_mmap_policy_fault,
 479 };
 480
 481 int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 482 {
 483         if (vma->vm_flags & VM_SHARED) {
 484                 /* do not allow mprotect to make mapping writable */
 485                 vma->vm_flags &= ~VM_MAYWRITE;
 486
 487                 if (vma->vm_flags & VM_WRITE)
 488                         return -EACCES;
 489         }
 490
 491         vma->vm_flags |= VM_RESERVED;
 492         vma->vm_ops = &sel_mmap_policy_ops;
 493
 494         return 0;
 495 }
 496
 497 static const struct file_operations sel_policy_ops = {
 498         .open           = sel_open_policy,
 499         .read           = sel_read_policy,
 500         .mmap           = sel_mmap_policy,
 501         .release        = sel_release_policy,
 502 };
 503
 504 static ssize_t sel_write_load(struct file *file, const char __user *buf,
 505                               size_t count, loff_t *ppos)
 506
 507 {
 508         ssize_t length;
 509         void *data = NULL;
 510
 511         mutex_lock(&sel_mutex);
 512
 513         length = task_has_security(current, SECURITY__LOAD_POLICY);
 514         if (length)
 515                 goto out;
 516
 517         /* No partial writes. */
 518         length = -EINVAL;
 519         if (*ppos != 0)
 520                 goto out;
 521
 522         length = -EFBIG;
 523         if (count > 64 * 1024 * 1024)
 524                 goto out;
 525
 526         length = -ENOMEM;
 527         data = vmalloc(count);
 528         if (!data)
 529                 goto out;
 530
 531         length = -EFAULT;
 532         if (copy_from_user(data, buf, count) != 0)
 533                 goto out;
 534
 535         length = security_load_policy(data, count);
 536         if (length)
 537                 goto out;
 538
 539         length = sel_make_bools();
 540         if (length)
 541                 goto out1;
 542
 543         length = sel_make_classes();
 544         if (length)
 545                 goto out1;
 546
 547         length = sel_make_policycap();
 548         if (length)
 549                 goto out1;
 550
 551         length = count;
 552
 553 out1:
 554         audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 555                 "policy loaded auid=%u ses=%u",
 556                 audit_get_loginuid(current),
 557                 audit_get_sessionid(current));
 558 out:
 559         mutex_unlock(&sel_mutex);
 560         vfree(data);
 561         return length;
 562 }
 563
 564 static const struct file_operations sel_load_ops = {
 565         .write          = sel_write_load,
 566         .llseek         = generic_file_llseek,
 567 };
 568
 569 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 570 {
 571         char *canon = NULL;
 572         u32 sid, len;
 573         ssize_t length;
 574
 575         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
 576         if (length)
 577                 goto out;
 578
 579         length = security_context_to_sid(buf, size, &sid);
 580         if (length)
 581                 goto out;
 582
 583         length = security_sid_to_context(sid, &canon, &len);
 584         if (length)
 585                 goto out;
 586
 587         length = -ERANGE;
 588         if (len > SIMPLE_TRANSACTION_LIMIT) {
 589                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 590                         "payload max\n", __func__, len);
 591                 goto out;
 592         }
 593
 594         memcpy(buf, canon, len);
 595         length = len;
 596 out:
 597         kfree(canon);
 598         return length;
 599 }
 600
 601 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 602                                      size_t count, loff_t *ppos)
 603 {
 604         char tmpbuf[TMPBUFLEN];
 605         ssize_t length;
 606
 607         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
 608         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 609 }
 610
 611 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 612                                       size_t count, loff_t *ppos)
 613 {
 614         char *page = NULL;
 615         ssize_t length;
 616         unsigned int new_value;
 617
 618         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
 619         if (length)
 620                 goto out;
 621
 622         length = -ENOMEM;
 623         if (count >= PAGE_SIZE)
 624                 goto out;
 625
 626         /* No partial writes. */
 627         length = -EINVAL;
 628         if (*ppos != 0)
 629                 goto out;
 630
 631         length = -ENOMEM;
 632         page = (char *)get_zeroed_page(GFP_KERNEL);
 633         if (!page)
 634                 goto out;
 635
 636         length = -EFAULT;
 637         if (copy_from_user(page, buf, count))
 638                 goto out;
 639
 640         length = -EINVAL;
 641         if (sscanf(page, "%u", &new_value) != 1)
 642                 goto out;
 643
 644         selinux_checkreqprot = new_value ? 1 : 0;
 645         length = count;
 646 out:
 647         free_page((unsigned long) page);
 648         return length;
 649 }
 650 static const struct file_operations sel_checkreqprot_ops = {
 651         .read           = sel_read_checkreqprot,
 652         .write          = sel_write_checkreqprot,
 653         .llseek         = generic_file_llseek,
 654 };
 655
 656 /*
 657  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 658  */
 659 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 660 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 661 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 662 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 663 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 664
 665 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 666         [SEL_ACCESS] = sel_write_access,
 667         [SEL_CREATE] = sel_write_create,
 668         [SEL_RELABEL] = sel_write_relabel,
 669         [SEL_USER] = sel_write_user,
 670         [SEL_MEMBER] = sel_write_member,
 671         [SEL_CONTEXT] = sel_write_context,
 672 };
 673
 674 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 675 {
 676         ino_t ino = file->f_path.dentry->d_inode->i_ino;
 677         char *data;
 678         ssize_t rv;
 679
 680         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 681                 return -EINVAL;
 682
 683         data = simple_transaction_get(file, buf, size);
 684         if (IS_ERR(data))
 685                 return PTR_ERR(data);
 686
 687         rv = write_op[ino](file, data, size);
 688         if (rv > 0) {
 689                 simple_transaction_set(file, rv);
 690                 rv = size;
 691         }
 692         return rv;
 693 }
 694
 695 static const struct file_operations transaction_ops = {
 696         .write          = selinux_transaction_write,
 697         .read           = simple_transaction_read,
 698         .release        = simple_transaction_release,
 699         .llseek         = generic_file_llseek,
 700 };
 701
 702 /*
 703  * payload - write methods
 704  * If the method has a response, the response should be put in buf,
 705  * and the length returned.  Otherwise return 0 or and -error.
 706  */
 707
 708 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 709 {
 710         char *scon = NULL, *tcon = NULL;
 711         u32 ssid, tsid;
 712         u16 tclass;
 713         struct av_decision avd;
 714         ssize_t length;
 715
 716         length = task_has_security(current, SECURITY__COMPUTE_AV);
 717         if (length)
 718                 goto out;
 719
 720         length = -ENOMEM;
 721         scon = kzalloc(size + 1, GFP_KERNEL);
 722         if (!scon)
 723                 goto out;
 724
 725         length = -ENOMEM;
 726         tcon = kzalloc(size + 1, GFP_KERNEL);
 727         if (!tcon)
 728                 goto out;
 729
 730         length = -EINVAL;
 731         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 732                 goto out;
 733
 734         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 735         if (length)
 736                 goto out;
 737
 738         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 739         if (length)
 740                 goto out;
 741
 742         security_compute_av_user(ssid, tsid, tclass, &avd);
 743
 744         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 745                           "%x %x %x %x %u %x",
 746                           avd.allowed, 0xffffffff,
 747                           avd.auditallow, avd.auditdeny,
 748                           avd.seqno, avd.flags);
 749 out:
 750         kfree(tcon);
 751         kfree(scon);
 752         return length;
 753 }
 754
 755 static inline int hexcode_to_int(int code) {
 756         if (code == '\0' || !isxdigit(code))
 757                 return -1;
 758         if (isdigit(code))
 759                 return code - '0';
 760         return tolower(code) - 'a' + 10;
 761 }
 762
 763 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 764 {
 765         char *scon = NULL, *tcon = NULL;
 766         char *namebuf = NULL, *objname = NULL;
 767         u32 ssid, tsid, newsid;
 768         u16 tclass;
 769         ssize_t length;
 770         char *newcon = NULL;
 771         u32 len;
 772         int nargs;
 773
 774         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 775         if (length)
 776                 goto out;
 777
 778         length = -ENOMEM;
 779         scon = kzalloc(size + 1, GFP_KERNEL);
 780         if (!scon)
 781                 goto out;
 782
 783         length = -ENOMEM;
 784         tcon = kzalloc(size + 1, GFP_KERNEL);
 785         if (!tcon)
 786                 goto out;
 787
 788         length = -ENOMEM;
 789         namebuf = kzalloc(size + 1, GFP_KERNEL);
 790         if (!namebuf)
 791                 goto out;
 792
 793         length = -EINVAL;
 794         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 795         if (nargs < 3 || nargs > 4)
 796                 goto out;
 797         if (nargs == 4) {
 798                 /*
 799                  * If and when the name of new object to be queried contains
 800                  * either whitespace or multibyte characters, they shall be
 801                  * encoded based on the percentage-encoding rule.
 802                  * If not encoded, the sscanf logic picks up only left-half
 803                  * of the supplied name; splitted by a whitespace unexpectedly.
 804                  */
 805                 char   *r, *w;
 806                 int     c1, c2;
 807
 808                 r = w = namebuf;
 809                 do {
 810                         c1 = *r++;
 811                         if (c1 == '+')
 812                                 c1 = ' ';
 813                         else if (c1 == '%') {
 814                                 if ((c1 = hexcode_to_int(*r++)) < 0)
 815                                         goto out;
 816                                 if ((c2 = hexcode_to_int(*r++)) < 0)
 817                                         goto out;
 818                                 c1 = (c1 << 4) | c2;
 819                         }
 820                         *w++ = c1;
 821                 } while (c1 != '\0');
 822
 823                 objname = namebuf;
 824         }
 825
 826         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 827         if (length)
 828                 goto out;
 829
 830         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 831         if (length)
 832                 goto out;
 833
 834         length = security_transition_sid_user(ssid, tsid, tclass,
 835                                               objname, &newsid);
 836         if (length)
 837                 goto out;
 838
 839         length = security_sid_to_context(newsid, &newcon, &len);
 840         if (length)
 841                 goto out;
 842
 843         length = -ERANGE;
 844         if (len > SIMPLE_TRANSACTION_LIMIT) {
 845                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 846                         "payload max\n", __func__, len);
 847                 goto out;
 848         }
 849
 850         memcpy(buf, newcon, len);
 851         length = len;
 852 out:
 853         kfree(newcon);
 854         kfree(namebuf);
 855         kfree(tcon);
 856         kfree(scon);
 857         return length;
 858 }
 859
 860 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 861 {
 862         char *scon = NULL, *tcon = NULL;
 863         u32 ssid, tsid, newsid;
 864         u16 tclass;
 865         ssize_t length;
 866         char *newcon = NULL;
 867         u32 len;
 868
 869         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 870         if (length)
 871                 goto out;
 872
 873         length = -ENOMEM;
 874         scon = kzalloc(size + 1, GFP_KERNEL);
 875         if (!scon)
 876                 goto out;
 877
 878         length = -ENOMEM;
 879         tcon = kzalloc(size + 1, GFP_KERNEL);
 880         if (!tcon)
 881                 goto out;
 882
 883         length = -EINVAL;
 884         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 885                 goto out;
 886
 887         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 888         if (length)
 889                 goto out;
 890
 891         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 892         if (length)
 893                 goto out;
 894
 895         length = security_change_sid(ssid, tsid, tclass, &newsid);
 896         if (length)
 897                 goto out;
 898
 899         length = security_sid_to_context(newsid, &newcon, &len);
 900         if (length)
 901                 goto out;
 902
 903         length = -ERANGE;
 904         if (len > SIMPLE_TRANSACTION_LIMIT)
 905                 goto out;
 906
 907         memcpy(buf, newcon, len);
 908         length = len;
 909 out:
 910         kfree(newcon);
 911         kfree(tcon);
 912         kfree(scon);
 913         return length;
 914 }
 915
 916 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
 917 {
 918         char *con = NULL, *user = NULL, *ptr;
 919         u32 sid, *sids = NULL;
 920         ssize_t length;
 921         char *newcon;
 922         int i, rc;
 923         u32 len, nsids;
 924
 925         length = task_has_security(current, SECURITY__COMPUTE_USER);
 926         if (length)
 927                 goto out;;
 928
 929         length = -ENOMEM;
 930         con = kzalloc(size + 1, GFP_KERNEL);
 931         if (!con)
 932                 goto out;;
 933
 934         length = -ENOMEM;
 935         user = kzalloc(size + 1, GFP_KERNEL);
 936         if (!user)
 937                 goto out;
 938
 939         length = -EINVAL;
 940         if (sscanf(buf, "%s %s", con, user) != 2)
 941                 goto out;
 942
 943         length = security_context_to_sid(con, strlen(con) + 1, &sid);
 944         if (length)
 945                 goto out;
 946
 947         length = security_get_user_sids(sid, user, &sids, &nsids);
 948         if (length)
 949                 goto out;
 950
 951         length = sprintf(buf, "%u", nsids) + 1;
 952         ptr = buf + length;
 953         for (i = 0; i < nsids; i++) {
 954                 rc = security_sid_to_context(sids[i], &newcon, &len);
 955                 if (rc) {
 956                         length = rc;
 957                         goto out;
 958                 }
 959                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
 960                         kfree(newcon);
 961                         length = -ERANGE;
 962                         goto out;
 963                 }
 964                 memcpy(ptr, newcon, len);
 965                 kfree(newcon);
 966                 ptr += len;
 967                 length += len;
 968         }
 969 out:
 970         kfree(sids);
 971         kfree(user);
 972         kfree(con);
 973         return length;
 974 }
 975
 976 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
 977 {
 978         char *scon = NULL, *tcon = NULL;
 979         u32 ssid, tsid, newsid;
 980         u16 tclass;
 981         ssize_t length;
 982         char *newcon = NULL;
 983         u32 len;
 984
 985         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
 986         if (length)
 987                 goto out;
 988
 989         length = -ENOMEM;
 990         scon = kzalloc(size + 1, GFP_KERNEL);
 991         if (!scon)
 992                 goto out;;
 993
 994         length = -ENOMEM;
 995         tcon = kzalloc(size + 1, GFP_KERNEL);
 996         if (!tcon)
 997                 goto out;
 998
 999         length = -EINVAL;
1000         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1001                 goto out;
1002
1003         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
1004         if (length)
1005                 goto out;
1006
1007         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
1008         if (length)
1009                 goto out;
1010
1011         length = security_member_sid(ssid, tsid, tclass, &newsid);
1012         if (length)
1013                 goto out;
1014
1015         length = security_sid_to_context(newsid, &newcon, &len);
1016         if (length)
1017                 goto out;
1018
1019         length = -ERANGE;
1020         if (len > SIMPLE_TRANSACTION_LIMIT) {
1021                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1022                         "payload max\n", __func__, len);
1023                 goto out;
1024         }
1025
1026         memcpy(buf, newcon, len);
1027         length = len;
1028 out:
1029         kfree(newcon);
1030         kfree(tcon);
1031         kfree(scon);
1032         return length;
1033 }
1034
1035 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1036 {
1037         struct inode *ret = new_inode(sb);
1038
1039         if (ret) {
1040                 ret->i_mode = mode;
1041                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1042         }
1043         return ret;
1044 }
1045
1046 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1047                              size_t count, loff_t *ppos)
1048 {
1049         char *page = NULL;
1050         ssize_t length;
1051         ssize_t ret;
1052         int cur_enforcing;
1053         struct inode *inode = filep->f_path.dentry->d_inode;
1054         unsigned index = inode->i_ino & SEL_INO_MASK;
1055         const char *name = filep->f_path.dentry->d_name.name;
1056
1057         mutex_lock(&sel_mutex);
1058
1059         ret = -EINVAL;
1060         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1061                 goto out;
1062
1063         ret = -ENOMEM;
1064         page = (char *)get_zeroed_page(GFP_KERNEL);
1065         if (!page)
1066                 goto out;
1067
1068         cur_enforcing = security_get_bool_value(index);
1069         if (cur_enforcing < 0) {
1070                 ret = cur_enforcing;
1071                 goto out;
1072         }
1073         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1074                           bool_pending_values[index]);
1075         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1076 out:
1077         mutex_unlock(&sel_mutex);
1078         free_page((unsigned long)page);
1079         return ret;
1080 }
1081
1082 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1083                               size_t count, loff_t *ppos)
1084 {
1085         char *page = NULL;
1086         ssize_t length;
1087         int new_value;
1088         struct inode *inode = filep->f_path.dentry->d_inode;
1089         unsigned index = inode->i_ino & SEL_INO_MASK;
1090         const char *name = filep->f_path.dentry->d_name.name;
1091
1092         mutex_lock(&sel_mutex);
1093
1094         length = task_has_security(current, SECURITY__SETBOOL);
1095         if (length)
1096                 goto out;
1097
1098         length = -EINVAL;
1099         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1100                 goto out;
1101
1102         length = -ENOMEM;
1103         if (count >= PAGE_SIZE)
1104                 goto out;
1105
1106         /* No partial writes. */
1107         length = -EINVAL;
1108         if (*ppos != 0)
1109                 goto out;
1110
1111         length = -ENOMEM;
1112         page = (char *)get_zeroed_page(GFP_KERNEL);
1113         if (!page)
1114                 goto out;
1115
1116         length = -EFAULT;
1117         if (copy_from_user(page, buf, count))
1118                 goto out;
1119
1120         length = -EINVAL;
1121         if (sscanf(page, "%d", &new_value) != 1)
1122                 goto out;
1123
1124         if (new_value)
1125                 new_value = 1;
1126
1127         bool_pending_values[index] = new_value;
1128         length = count;
1129
1130 out:
1131         mutex_unlock(&sel_mutex);
1132         free_page((unsigned long) page);
1133         return length;
1134 }
1135
1136 static const struct file_operations sel_bool_ops = {
1137         .read           = sel_read_bool,
1138         .write          = sel_write_bool,
1139         .llseek         = generic_file_llseek,
1140 };
1141
1142 static ssize_t sel_commit_bools_write(struct file *filep,
1143                                       const char __user *buf,
1144                                       size_t count, loff_t *ppos)
1145 {
1146         char *page = NULL;
1147         ssize_t length;
1148         int new_value;
1149
1150         mutex_lock(&sel_mutex);
1151
1152         length = task_has_security(current, SECURITY__SETBOOL);
1153         if (length)
1154                 goto out;
1155
1156         length = -ENOMEM;
1157         if (count >= PAGE_SIZE)
1158                 goto out;
1159
1160         /* No partial writes. */
1161         length = -EINVAL;
1162         if (*ppos != 0)
1163                 goto out;
1164
1165         length = -ENOMEM;
1166         page = (char *)get_zeroed_page(GFP_KERNEL);
1167         if (!page)
1168                 goto out;
1169
1170         length = -EFAULT;
1171         if (copy_from_user(page, buf, count))
1172                 goto out;
1173
1174         length = -EINVAL;
1175         if (sscanf(page, "%d", &new_value) != 1)
1176                 goto out;
1177
1178         length = 0;
1179         if (new_value && bool_pending_values)
1180                 length = security_set_bools(bool_num, bool_pending_values);
1181
1182         if (!length)
1183                 length = count;
1184
1185 out:
1186         mutex_unlock(&sel_mutex);
1187         free_page((unsigned long) page);
1188         return length;
1189 }
1190
1191 static const struct file_operations sel_commit_bools_ops = {
1192         .write          = sel_commit_bools_write,
1193         .llseek         = generic_file_llseek,
1194 };
1195
1196 static void sel_remove_entries(struct dentry *de)
1197 {
1198         struct list_head *node;
1199
1200         spin_lock(&de->d_lock);
1201         node = de->d_subdirs.next;
1202         while (node != &de->d_subdirs) {
1203                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1204
1205                 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
1206                 list_del_init(node);
1207
1208                 if (d->d_inode) {
1209                         dget_dlock(d);
1210                         spin_unlock(&de->d_lock);
1211                         spin_unlock(&d->d_lock);
1212                         d_delete(d);
1213                         simple_unlink(de->d_inode, d);
1214                         dput(d);
1215                         spin_lock(&de->d_lock);
1216                 } else
1217                         spin_unlock(&d->d_lock);
1218                 node = de->d_subdirs.next;
1219         }
1220
1221         spin_unlock(&de->d_lock);
1222 }
1223
1224 #define BOOL_DIR_NAME "booleans"
1225
1226 static int sel_make_bools(void)
1227 {
1228         int i, ret;
1229         ssize_t len;
1230         struct dentry *dentry = NULL;
1231         struct dentry *dir = bool_dir;
1232         struct inode *inode = NULL;
1233         struct inode_security_struct *isec;
1234         char **names = NULL, *page;
1235         int num;
1236         int *values = NULL;
1237         u32 sid;
1238
1239         /* remove any existing files */
1240         for (i = 0; i < bool_num; i++)
1241                 kfree(bool_pending_names[i]);
1242         kfree(bool_pending_names);
1243         kfree(bool_pending_values);
1244         bool_pending_names = NULL;
1245         bool_pending_values = NULL;
1246
1247         sel_remove_entries(dir);
1248
1249         ret = -ENOMEM;
1250         page = (char *)get_zeroed_page(GFP_KERNEL);
1251         if (!page)
1252                 goto out;
1253
1254         ret = security_get_bools(&num, &names, &values);
1255         if (ret)
1256                 goto out;
1257
1258         for (i = 0; i < num; i++) {
1259                 ret = -ENOMEM;
1260                 dentry = d_alloc_name(dir, names[i]);
1261                 if (!dentry)
1262                         goto out;
1263
1264                 ret = -ENOMEM;
1265                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1266                 if (!inode)
1267                         goto out;
1268
1269                 ret = -EINVAL;
1270                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1271                 if (len < 0)
1272                         goto out;
1273
1274                 ret = -ENAMETOOLONG;
1275                 if (len >= PAGE_SIZE)
1276                         goto out;
1277
1278                 isec = (struct inode_security_struct *)inode->i_security;
1279                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1280                 if (ret)
1281                         goto out;
1282
1283                 isec->sid = sid;
1284                 isec->initialized = 1;
1285                 inode->i_fop = &sel_bool_ops;
1286                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1287                 d_add(dentry, inode);
1288         }
1289         bool_num = num;
1290         bool_pending_names = names;
1291         bool_pending_values = values;
1292
1293         free_page((unsigned long)page);
1294         return 0;
1295 out:
1296         free_page((unsigned long)page);
1297
1298         if (names) {
1299                 for (i = 0; i < num; i++)
1300                         kfree(names[i]);
1301                 kfree(names);
1302         }
1303         kfree(values);
1304         sel_remove_entries(dir);
1305
1306         return ret;
1307 }
1308
1309 #define NULL_FILE_NAME "null"
1310
1311 struct dentry *selinux_null;
1312
1313 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1314                                             size_t count, loff_t *ppos)
1315 {
1316         char tmpbuf[TMPBUFLEN];
1317         ssize_t length;
1318
1319         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1320         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1321 }
1322
1323 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1324                                              const char __user *buf,
1325                                              size_t count, loff_t *ppos)
1326
1327 {
1328         char *page = NULL;
1329         ssize_t ret;
1330         int new_value;
1331
1332         ret = task_has_security(current, SECURITY__SETSECPARAM);
1333         if (ret)
1334                 goto out;
1335
1336         ret = -ENOMEM;
1337         if (count >= PAGE_SIZE)
1338                 goto out;
1339
1340         /* No partial writes. */
1341         ret = -EINVAL;
1342         if (*ppos != 0)
1343                 goto out;
1344
1345         ret = -ENOMEM;
1346         page = (char *)get_zeroed_page(GFP_KERNEL);
1347         if (!page)
1348                 goto out;
1349
1350         ret = -EFAULT;
1351         if (copy_from_user(page, buf, count))
1352                 goto out;
1353
1354         ret = -EINVAL;
1355         if (sscanf(page, "%u", &new_value) != 1)
1356                 goto out;
1357
1358         avc_cache_threshold = new_value;
1359
1360         ret = count;
1361 out:
1362         free_page((unsigned long)page);
1363         return ret;
1364 }
1365
1366 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1367                                        size_t count, loff_t *ppos)
1368 {
1369         char *page;
1370         ssize_t length;
1371
1372         page = (char *)__get_free_page(GFP_KERNEL);
1373         if (!page)
1374                 return -ENOMEM;
1375
1376         length = avc_get_hash_stats(page);
1377         if (length >= 0)
1378                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1379         free_page((unsigned long)page);
1380
1381         return length;
1382 }
1383
1384 static const struct file_operations sel_avc_cache_threshold_ops = {
1385         .read           = sel_read_avc_cache_threshold,
1386         .write          = sel_write_avc_cache_threshold,
1387         .llseek         = generic_file_llseek,
1388 };
1389
1390 static const struct file_operations sel_avc_hash_stats_ops = {
1391         .read           = sel_read_avc_hash_stats,
1392         .llseek         = generic_file_llseek,
1393 };
1394
1395 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1396 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1397 {
1398         int cpu;
1399
1400         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1401                 if (!cpu_possible(cpu))
1402                         continue;
1403                 *idx = cpu + 1;
1404                 return &per_cpu(avc_cache_stats, cpu);
1405         }
1406         return NULL;
1407 }
1408
1409 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1410 {
1411         loff_t n = *pos - 1;
1412
1413         if (*pos == 0)
1414                 return SEQ_START_TOKEN;
1415
1416         return sel_avc_get_stat_idx(&n);
1417 }
1418
1419 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1420 {
1421         return sel_avc_get_stat_idx(pos);
1422 }
1423
1424 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1425 {
1426         struct avc_cache_stats *st = v;
1427
1428         if (v == SEQ_START_TOKEN)
1429                 seq_printf(seq, "lookups hits misses allocations reclaims "
1430                            "frees\n");
1431         else
1432                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1433                            st->hits, st->misses, st->allocations,
1434                            st->reclaims, st->frees);
1435         return 0;
1436 }
1437
1438 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1439 { }
1440
1441 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1442         .start          = sel_avc_stats_seq_start,
1443         .next           = sel_avc_stats_seq_next,
1444         .show           = sel_avc_stats_seq_show,
1445         .stop           = sel_avc_stats_seq_stop,
1446 };
1447
1448 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1449 {
1450         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1451 }
1452
1453 static const struct file_operations sel_avc_cache_stats_ops = {
1454         .open           = sel_open_avc_cache_stats,
1455         .read           = seq_read,
1456         .llseek         = seq_lseek,
1457         .release        = seq_release,
1458 };
1459 #endif
1460
1461 static int sel_make_avc_files(struct dentry *dir)
1462 {
1463         int i;
1464         static struct tree_descr files[] = {
1465                 { "cache_threshold",
1466                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1467                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1468 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1469                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1470 #endif
1471         };
1472
1473         for (i = 0; i < ARRAY_SIZE(files); i++) {
1474                 struct inode *inode;
1475                 struct dentry *dentry;
1476
1477                 dentry = d_alloc_name(dir, files[i].name);
1478                 if (!dentry)
1479                         return -ENOMEM;
1480
1481                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1482                 if (!inode)
1483                         return -ENOMEM;
1484
1485                 inode->i_fop = files[i].ops;
1486                 inode->i_ino = ++sel_last_ino;
1487                 d_add(dentry, inode);
1488         }
1489
1490         return 0;
1491 }
1492
1493 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1494                                 size_t count, loff_t *ppos)
1495 {
1496         struct inode *inode;
1497         char *con;
1498         u32 sid, len;
1499         ssize_t ret;
1500
1501         inode = file->f_path.dentry->d_inode;
1502         sid = inode->i_ino&SEL_INO_MASK;
1503         ret = security_sid_to_context(sid, &con, &len);
1504         if (ret)
1505                 return ret;
1506
1507         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1508         kfree(con);
1509         return ret;
1510 }
1511
1512 static const struct file_operations sel_initcon_ops = {
1513         .read           = sel_read_initcon,
1514         .llseek         = generic_file_llseek,
1515 };
1516
1517 static int sel_make_initcon_files(struct dentry *dir)
1518 {
1519         int i;
1520
1521         for (i = 1; i <= SECINITSID_NUM; i++) {
1522                 struct inode *inode;
1523                 struct dentry *dentry;
1524                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1525                 if (!dentry)
1526                         return -ENOMEM;
1527
1528                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1529                 if (!inode)
1530                         return -ENOMEM;
1531
1532                 inode->i_fop = &sel_initcon_ops;
1533                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1534                 d_add(dentry, inode);
1535         }
1536
1537         return 0;
1538 }
1539
1540 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1541 {
1542         return a / b - (a % b < 0);
1543 }
1544
1545 static inline unsigned long sel_class_to_ino(u16 class)
1546 {
1547         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1548 }
1549
1550 static inline u16 sel_ino_to_class(unsigned long ino)
1551 {
1552         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1553 }
1554
1555 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1556 {
1557         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1558 }
1559
1560 static inline u32 sel_ino_to_perm(unsigned long ino)
1561 {
1562         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1563 }
1564
1565 static ssize_t sel_read_class(struct file *file, char __user *buf,
1566                                 size_t count, loff_t *ppos)
1567 {
1568         ssize_t rc, len;
1569         char *page;
1570         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1571
1572         page = (char *)__get_free_page(GFP_KERNEL);
1573         if (!page)
1574                 return -ENOMEM;
1575
1576         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1577         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1578         free_page((unsigned long)page);
1579
1580         return rc;
1581 }
1582
1583 static const struct file_operations sel_class_ops = {
1584         .read           = sel_read_class,
1585         .llseek         = generic_file_llseek,
1586 };
1587
1588 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1589                                 size_t count, loff_t *ppos)
1590 {
1591         ssize_t rc, len;
1592         char *page;
1593         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1594
1595         page = (char *)__get_free_page(GFP_KERNEL);
1596         if (!page)
1597                 return -ENOMEM;
1598
1599         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1600         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1601         free_page((unsigned long)page);
1602
1603         return rc;
1604 }
1605
1606 static const struct file_operations sel_perm_ops = {
1607         .read           = sel_read_perm,
1608         .llseek         = generic_file_llseek,
1609 };
1610
1611 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1612                                   size_t count, loff_t *ppos)
1613 {
1614         int value;
1615         char tmpbuf[TMPBUFLEN];
1616         ssize_t length;
1617         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1618
1619         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1620         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1621
1622         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1623 }
1624
1625 static const struct file_operations sel_policycap_ops = {
1626         .read           = sel_read_policycap,
1627         .llseek         = generic_file_llseek,
1628 };
1629
1630 static int sel_make_perm_files(char *objclass, int classvalue,
1631                                 struct dentry *dir)
1632 {
1633         int i, rc, nperms;
1634         char **perms;
1635
1636         rc = security_get_permissions(objclass, &perms, &nperms);
1637         if (rc)
1638                 return rc;
1639
1640         for (i = 0; i < nperms; i++) {
1641                 struct inode *inode;
1642                 struct dentry *dentry;
1643
1644                 rc = -ENOMEM;
1645                 dentry = d_alloc_name(dir, perms[i]);
1646                 if (!dentry)
1647                         goto out;
1648
1649                 rc = -ENOMEM;
1650                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1651                 if (!inode)
1652                         goto out;
1653
1654                 inode->i_fop = &sel_perm_ops;
1655                 /* i+1 since perm values are 1-indexed */
1656                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1657                 d_add(dentry, inode);
1658         }
1659         rc = 0;
1660 out:
1661         for (i = 0; i < nperms; i++)
1662                 kfree(perms[i]);
1663         kfree(perms);
1664         return rc;
1665 }
1666
1667 static int sel_make_class_dir_entries(char *classname, int index,
1668                                         struct dentry *dir)
1669 {
1670         struct dentry *dentry = NULL;
1671         struct inode *inode = NULL;
1672         int rc;
1673
1674         dentry = d_alloc_name(dir, "index");
1675         if (!dentry)
1676                 return -ENOMEM;
1677
1678         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1679         if (!inode)
1680                 return -ENOMEM;
1681
1682         inode->i_fop = &sel_class_ops;
1683         inode->i_ino = sel_class_to_ino(index);
1684         d_add(dentry, inode);
1685
1686         dentry = d_alloc_name(dir, "perms");
1687         if (!dentry)
1688                 return -ENOMEM;
1689
1690         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1691         if (rc)
1692                 return rc;
1693
1694         rc = sel_make_perm_files(classname, index, dentry);
1695
1696         return rc;
1697 }
1698
1699 static void sel_remove_classes(void)
1700 {
1701         struct list_head *class_node;
1702
1703         list_for_each(class_node, &class_dir->d_subdirs) {
1704                 struct dentry *class_subdir = list_entry(class_node,
1705                                         struct dentry, d_u.d_child);
1706                 struct list_head *class_subdir_node;
1707
1708                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1709                         struct dentry *d = list_entry(class_subdir_node,
1710                                                 struct dentry, d_u.d_child);
1711
1712                         if (d->d_inode)
1713                                 if (d->d_inode->i_mode & S_IFDIR)
1714                                         sel_remove_entries(d);
1715                 }
1716
1717                 sel_remove_entries(class_subdir);
1718         }
1719
1720         sel_remove_entries(class_dir);
1721 }
1722
1723 static int sel_make_classes(void)
1724 {
1725         int rc, nclasses, i;
1726         char **classes;
1727
1728         /* delete any existing entries */
1729         sel_remove_classes();
1730
1731         rc = security_get_classes(&classes, &nclasses);
1732         if (rc)
1733                 return rc;
1734
1735         /* +2 since classes are 1-indexed */
1736         last_class_ino = sel_class_to_ino(nclasses + 2);
1737
1738         for (i = 0; i < nclasses; i++) {
1739                 struct dentry *class_name_dir;
1740
1741                 rc = -ENOMEM;
1742                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1743                 if (!class_name_dir)
1744                         goto out;
1745
1746                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1747                                 &last_class_ino);
1748                 if (rc)
1749                         goto out;
1750
1751                 /* i+1 since class values are 1-indexed */
1752                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1753                                 class_name_dir);
1754                 if (rc)
1755                         goto out;
1756         }
1757         rc = 0;
1758 out:
1759         for (i = 0; i < nclasses; i++)
1760                 kfree(classes[i]);
1761         kfree(classes);
1762         return rc;
1763 }
1764
1765 static int sel_make_policycap(void)
1766 {
1767         unsigned int iter;
1768         struct dentry *dentry = NULL;
1769         struct inode *inode = NULL;
1770
1771         sel_remove_entries(policycap_dir);
1772
1773         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1774                 if (iter < ARRAY_SIZE(policycap_names))
1775                         dentry = d_alloc_name(policycap_dir,
1776                                               policycap_names[iter]);
1777                 else
1778                         dentry = d_alloc_name(policycap_dir, "unknown");
1779
1780                 if (dentry == NULL)
1781                         return -ENOMEM;
1782
1783                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1784                 if (inode == NULL)
1785                         return -ENOMEM;
1786
1787                 inode->i_fop = &sel_policycap_ops;
1788                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1789                 d_add(dentry, inode);
1790         }
1791
1792         return 0;
1793 }
1794
1795 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1796                         unsigned long *ino)
1797 {
1798         struct inode *inode;
1799
1800         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1801         if (!inode)
1802                 return -ENOMEM;
1803
1804         inode->i_op = &simple_dir_inode_operations;
1805         inode->i_fop = &simple_dir_operations;
1806         inode->i_ino = ++(*ino);
1807         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1808         inc_nlink(inode);
1809         d_add(dentry, inode);
1810         /* bump link count on parent directory, too */
1811         inc_nlink(dir);
1812
1813         return 0;
1814 }
1815
1816 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1817 {
1818         int ret;
1819         struct dentry *dentry;
1820         struct inode *inode, *root_inode;
1821         struct inode_security_struct *isec;
1822
1823         static struct tree_descr selinux_files[] = {
1824                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1825                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1826                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1827                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1828                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1829                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1830                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1831                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1832                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1833                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1834                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1835                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1836                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1837                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1838                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1839                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1840                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR},
1841                 /* last one */ {""}
1842         };
1843         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1844         if (ret)
1845                 goto err;
1846
1847         root_inode = sb->s_root->d_inode;
1848
1849         ret = -ENOMEM;
1850         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1851         if (!dentry)
1852                 goto err;
1853
1854         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1855         if (ret)
1856                 goto err;
1857
1858         bool_dir = dentry;
1859
1860         ret = -ENOMEM;
1861         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1862         if (!dentry)
1863                 goto err;
1864
1865         ret = -ENOMEM;
1866         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1867         if (!inode)
1868                 goto err;
1869
1870         inode->i_ino = ++sel_last_ino;
1871         isec = (struct inode_security_struct *)inode->i_security;
1872         isec->sid = SECINITSID_DEVNULL;
1873         isec->sclass = SECCLASS_CHR_FILE;
1874         isec->initialized = 1;
1875
1876         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1877         d_add(dentry, inode);
1878         selinux_null = dentry;
1879
1880         ret = -ENOMEM;
1881         dentry = d_alloc_name(sb->s_root, "avc");
1882         if (!dentry)
1883                 goto err;
1884
1885         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1886         if (ret)
1887                 goto err;
1888
1889         ret = sel_make_avc_files(dentry);
1890         if (ret)
1891                 goto err;
1892
1893         ret = -ENOMEM;
1894         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1895         if (!dentry)
1896                 goto err;
1897
1898         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1899         if (ret)
1900                 goto err;
1901
1902         ret = sel_make_initcon_files(dentry);
1903         if (ret)
1904                 goto err;
1905
1906         ret = -ENOMEM;
1907         dentry = d_alloc_name(sb->s_root, "class");
1908         if (!dentry)
1909                 goto err;
1910
1911         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1912         if (ret)
1913                 goto err;
1914
1915         class_dir = dentry;
1916
1917         ret = -ENOMEM;
1918         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1919         if (!dentry)
1920                 goto err;
1921
1922         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1923         if (ret)
1924                 goto err;
1925
1926         policycap_dir = dentry;
1927
1928         return 0;
1929 err:
1930         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1931                 __func__);
1932         return ret;
1933 }
1934
1935 static struct dentry *sel_mount(struct file_system_type *fs_type,
1936                       int flags, const char *dev_name, void *data)
1937 {
1938         return mount_single(fs_type, flags, data, sel_fill_super);
1939 }
1940
1941 static struct file_system_type sel_fs_type = {
1942         .name           = "selinuxfs",
1943         .mount          = sel_mount,
1944         .kill_sb        = kill_litter_super,
1945 };
1946
1947 struct vfsmount *selinuxfs_mount;
1948 static struct kobject *selinuxfs_kobj;
1949
1950 static int __init init_sel_fs(void)
1951 {
1952         int err;
1953
1954         if (!selinux_enabled)
1955                 return 0;
1956
1957         selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj);
1958         if (!selinuxfs_kobj)
1959                 return -ENOMEM;
1960
1961         err = register_filesystem(&sel_fs_type);
1962         if (err) {
1963                 kobject_put(selinuxfs_kobj);
1964                 return err;
1965         }
1966
1967         selinuxfs_mount = kern_mount(&sel_fs_type);
1968         if (IS_ERR(selinuxfs_mount)) {
1969                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1970                 err = PTR_ERR(selinuxfs_mount);
1971                 selinuxfs_mount = NULL;
1972         }
1973
1974         return err;
1975 }
1976
1977 __initcall(init_sel_fs);
1978
1979 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1980 void exit_sel_fs(void)
1981 {
1982         kobject_put(selinuxfs_kobj);
1983         unregister_filesystem(&sel_fs_type);
1984 }
1985 #endif