security/selinux/selinuxfs.c

   1 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
   2  *
   3  *      Added conditional policy language extensions
   4  *
   5  *  Updated: Hewlett-Packard <paul@paul-moore.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 ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 756 {
 757         char *scon = NULL, *tcon = NULL;
 758         char *namebuf = NULL, *objname = NULL;
 759         u32 ssid, tsid, newsid;
 760         u16 tclass;
 761         ssize_t length;
 762         char *newcon = NULL;
 763         u32 len;
 764         int nargs;
 765
 766         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 767         if (length)
 768                 goto out;
 769
 770         length = -ENOMEM;
 771         scon = kzalloc(size + 1, GFP_KERNEL);
 772         if (!scon)
 773                 goto out;
 774
 775         length = -ENOMEM;
 776         tcon = kzalloc(size + 1, GFP_KERNEL);
 777         if (!tcon)
 778                 goto out;
 779
 780         length = -ENOMEM;
 781         namebuf = kzalloc(size + 1, GFP_KERNEL);
 782         if (!namebuf)
 783                 goto out;
 784
 785         length = -EINVAL;
 786         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 787         if (nargs < 3 || nargs > 4)
 788                 goto out;
 789         if (nargs == 4) {
 790                 /*
 791                  * If and when the name of new object to be queried contains
 792                  * either whitespace or multibyte characters, they shall be
 793                  * encoded based on the percentage-encoding rule.
 794                  * If not encoded, the sscanf logic picks up only left-half
 795                  * of the supplied name; splitted by a whitespace unexpectedly.
 796                  */
 797                 char   *r, *w;
 798                 int     c1, c2;
 799
 800                 r = w = namebuf;
 801                 do {
 802                         c1 = *r++;
 803                         if (c1 == '+')
 804                                 c1 = ' ';
 805                         else if (c1 == '%') {
 806                                 c1 = hex_to_bin(*r++);
 807                                 if (c1 < 0)
 808                                         goto out;
 809                                 c2 = hex_to_bin(*r++);
 810                                 if (c2 < 0)
 811                                         goto out;
 812                                 c1 = (c1 << 4) | c2;
 813                         }
 814                         *w++ = c1;
 815                 } while (c1 != '\0');
 816
 817                 objname = namebuf;
 818         }
 819
 820         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 821         if (length)
 822                 goto out;
 823
 824         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 825         if (length)
 826                 goto out;
 827
 828         length = security_transition_sid_user(ssid, tsid, tclass,
 829                                               objname, &newsid);
 830         if (length)
 831                 goto out;
 832
 833         length = security_sid_to_context(newsid, &newcon, &len);
 834         if (length)
 835                 goto out;
 836
 837         length = -ERANGE;
 838         if (len > SIMPLE_TRANSACTION_LIMIT) {
 839                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
 840                         "payload max\n", __func__, len);
 841                 goto out;
 842         }
 843
 844         memcpy(buf, newcon, len);
 845         length = len;
 846 out:
 847         kfree(newcon);
 848         kfree(namebuf);
 849         kfree(tcon);
 850         kfree(scon);
 851         return length;
 852 }
 853
 854 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
 855 {
 856         char *scon = NULL, *tcon = NULL;
 857         u32 ssid, tsid, newsid;
 858         u16 tclass;
 859         ssize_t length;
 860         char *newcon = NULL;
 861         u32 len;
 862
 863         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 864         if (length)
 865                 goto out;
 866
 867         length = -ENOMEM;
 868         scon = kzalloc(size + 1, GFP_KERNEL);
 869         if (!scon)
 870                 goto out;
 871
 872         length = -ENOMEM;
 873         tcon = kzalloc(size + 1, GFP_KERNEL);
 874         if (!tcon)
 875                 goto out;
 876
 877         length = -EINVAL;
 878         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 879                 goto out;
 880
 881         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 882         if (length)
 883                 goto out;
 884
 885         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
 886         if (length)
 887                 goto out;
 888
 889         length = security_change_sid(ssid, tsid, tclass, &newsid);
 890         if (length)
 891                 goto out;
 892
 893         length = security_sid_to_context(newsid, &newcon, &len);
 894         if (length)
 895                 goto out;
 896
 897         length = -ERANGE;
 898         if (len > SIMPLE_TRANSACTION_LIMIT)
 899                 goto out;
 900
 901         memcpy(buf, newcon, len);
 902         length = len;
 903 out:
 904         kfree(newcon);
 905         kfree(tcon);
 906         kfree(scon);
 907         return length;
 908 }
 909
 910 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
 911 {
 912         char *con = NULL, *user = NULL, *ptr;
 913         u32 sid, *sids = NULL;
 914         ssize_t length;
 915         char *newcon;
 916         int i, rc;
 917         u32 len, nsids;
 918
 919         length = task_has_security(current, SECURITY__COMPUTE_USER);
 920         if (length)
 921                 goto out;
 922
 923         length = -ENOMEM;
 924         con = kzalloc(size + 1, GFP_KERNEL);
 925         if (!con)
 926                 goto out;
 927
 928         length = -ENOMEM;
 929         user = kzalloc(size + 1, GFP_KERNEL);
 930         if (!user)
 931                 goto out;
 932
 933         length = -EINVAL;
 934         if (sscanf(buf, "%s %s", con, user) != 2)
 935                 goto out;
 936
 937         length = security_context_to_sid(con, strlen(con) + 1, &sid);
 938         if (length)
 939                 goto out;
 940
 941         length = security_get_user_sids(sid, user, &sids, &nsids);
 942         if (length)
 943                 goto out;
 944
 945         length = sprintf(buf, "%u", nsids) + 1;
 946         ptr = buf + length;
 947         for (i = 0; i < nsids; i++) {
 948                 rc = security_sid_to_context(sids[i], &newcon, &len);
 949                 if (rc) {
 950                         length = rc;
 951                         goto out;
 952                 }
 953                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
 954                         kfree(newcon);
 955                         length = -ERANGE;
 956                         goto out;
 957                 }
 958                 memcpy(ptr, newcon, len);
 959                 kfree(newcon);
 960                 ptr += len;
 961                 length += len;
 962         }
 963 out:
 964         kfree(sids);
 965         kfree(user);
 966         kfree(con);
 967         return length;
 968 }
 969
 970 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
 971 {
 972         char *scon = NULL, *tcon = NULL;
 973         u32 ssid, tsid, newsid;
 974         u16 tclass;
 975         ssize_t length;
 976         char *newcon = NULL;
 977         u32 len;
 978
 979         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
 980         if (length)
 981                 goto out;
 982
 983         length = -ENOMEM;
 984         scon = kzalloc(size + 1, GFP_KERNEL);
 985         if (!scon)
 986                 goto out;
 987
 988         length = -ENOMEM;
 989         tcon = kzalloc(size + 1, GFP_KERNEL);
 990         if (!tcon)
 991                 goto out;
 992
 993         length = -EINVAL;
 994         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 995                 goto out;
 996
 997         length = security_context_to_sid(scon, strlen(scon) + 1, &ssid);
 998         if (length)
 999                 goto out;
1000
1001         length = security_context_to_sid(tcon, strlen(tcon) + 1, &tsid);
1002         if (length)
1003                 goto out;
1004
1005         length = security_member_sid(ssid, tsid, tclass, &newsid);
1006         if (length)
1007                 goto out;
1008
1009         length = security_sid_to_context(newsid, &newcon, &len);
1010         if (length)
1011                 goto out;
1012
1013         length = -ERANGE;
1014         if (len > SIMPLE_TRANSACTION_LIMIT) {
1015                 printk(KERN_ERR "SELinux: %s:  context size (%u) exceeds "
1016                         "payload max\n", __func__, len);
1017                 goto out;
1018         }
1019
1020         memcpy(buf, newcon, len);
1021         length = len;
1022 out:
1023         kfree(newcon);
1024         kfree(tcon);
1025         kfree(scon);
1026         return length;
1027 }
1028
1029 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1030 {
1031         struct inode *ret = new_inode(sb);
1032
1033         if (ret) {
1034                 ret->i_mode = mode;
1035                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
1036         }
1037         return ret;
1038 }
1039
1040 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1041                              size_t count, loff_t *ppos)
1042 {
1043         char *page = NULL;
1044         ssize_t length;
1045         ssize_t ret;
1046         int cur_enforcing;
1047         struct inode *inode = filep->f_path.dentry->d_inode;
1048         unsigned index = inode->i_ino & SEL_INO_MASK;
1049         const char *name = filep->f_path.dentry->d_name.name;
1050
1051         mutex_lock(&sel_mutex);
1052
1053         ret = -EINVAL;
1054         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1055                 goto out;
1056
1057         ret = -ENOMEM;
1058         page = (char *)get_zeroed_page(GFP_KERNEL);
1059         if (!page)
1060                 goto out;
1061
1062         cur_enforcing = security_get_bool_value(index);
1063         if (cur_enforcing < 0) {
1064                 ret = cur_enforcing;
1065                 goto out;
1066         }
1067         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1068                           bool_pending_values[index]);
1069         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1070 out:
1071         mutex_unlock(&sel_mutex);
1072         free_page((unsigned long)page);
1073         return ret;
1074 }
1075
1076 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1077                               size_t count, loff_t *ppos)
1078 {
1079         char *page = NULL;
1080         ssize_t length;
1081         int new_value;
1082         struct inode *inode = filep->f_path.dentry->d_inode;
1083         unsigned index = inode->i_ino & SEL_INO_MASK;
1084         const char *name = filep->f_path.dentry->d_name.name;
1085
1086         mutex_lock(&sel_mutex);
1087
1088         length = task_has_security(current, SECURITY__SETBOOL);
1089         if (length)
1090                 goto out;
1091
1092         length = -EINVAL;
1093         if (index >= bool_num || strcmp(name, bool_pending_names[index]))
1094                 goto out;
1095
1096         length = -ENOMEM;
1097         if (count >= PAGE_SIZE)
1098                 goto out;
1099
1100         /* No partial writes. */
1101         length = -EINVAL;
1102         if (*ppos != 0)
1103                 goto out;
1104
1105         length = -ENOMEM;
1106         page = (char *)get_zeroed_page(GFP_KERNEL);
1107         if (!page)
1108                 goto out;
1109
1110         length = -EFAULT;
1111         if (copy_from_user(page, buf, count))
1112                 goto out;
1113
1114         length = -EINVAL;
1115         if (sscanf(page, "%d", &new_value) != 1)
1116                 goto out;
1117
1118         if (new_value)
1119                 new_value = 1;
1120
1121         bool_pending_values[index] = new_value;
1122         length = count;
1123
1124 out:
1125         mutex_unlock(&sel_mutex);
1126         free_page((unsigned long) page);
1127         return length;
1128 }
1129
1130 static const struct file_operations sel_bool_ops = {
1131         .read           = sel_read_bool,
1132         .write          = sel_write_bool,
1133         .llseek         = generic_file_llseek,
1134 };
1135
1136 static ssize_t sel_commit_bools_write(struct file *filep,
1137                                       const char __user *buf,
1138                                       size_t count, loff_t *ppos)
1139 {
1140         char *page = NULL;
1141         ssize_t length;
1142         int new_value;
1143
1144         mutex_lock(&sel_mutex);
1145
1146         length = task_has_security(current, SECURITY__SETBOOL);
1147         if (length)
1148                 goto out;
1149
1150         length = -ENOMEM;
1151         if (count >= PAGE_SIZE)
1152                 goto out;
1153
1154         /* No partial writes. */
1155         length = -EINVAL;
1156         if (*ppos != 0)
1157                 goto out;
1158
1159         length = -ENOMEM;
1160         page = (char *)get_zeroed_page(GFP_KERNEL);
1161         if (!page)
1162                 goto out;
1163
1164         length = -EFAULT;
1165         if (copy_from_user(page, buf, count))
1166                 goto out;
1167
1168         length = -EINVAL;
1169         if (sscanf(page, "%d", &new_value) != 1)
1170                 goto out;
1171
1172         length = 0;
1173         if (new_value && bool_pending_values)
1174                 length = security_set_bools(bool_num, bool_pending_values);
1175
1176         if (!length)
1177                 length = count;
1178
1179 out:
1180         mutex_unlock(&sel_mutex);
1181         free_page((unsigned long) page);
1182         return length;
1183 }
1184
1185 static const struct file_operations sel_commit_bools_ops = {
1186         .write          = sel_commit_bools_write,
1187         .llseek         = generic_file_llseek,
1188 };
1189
1190 static void sel_remove_entries(struct dentry *de)
1191 {
1192         struct list_head *node;
1193
1194         spin_lock(&de->d_lock);
1195         node = de->d_subdirs.next;
1196         while (node != &de->d_subdirs) {
1197                 struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
1198
1199                 spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
1200                 list_del_init(node);
1201
1202                 if (d->d_inode) {
1203                         dget_dlock(d);
1204                         spin_unlock(&de->d_lock);
1205                         spin_unlock(&d->d_lock);
1206                         d_delete(d);
1207                         simple_unlink(de->d_inode, d);
1208                         dput(d);
1209                         spin_lock(&de->d_lock);
1210                 } else
1211                         spin_unlock(&d->d_lock);
1212                 node = de->d_subdirs.next;
1213         }
1214
1215         spin_unlock(&de->d_lock);
1216 }
1217
1218 #define BOOL_DIR_NAME "booleans"
1219
1220 static int sel_make_bools(void)
1221 {
1222         int i, ret;
1223         ssize_t len;
1224         struct dentry *dentry = NULL;
1225         struct dentry *dir = bool_dir;
1226         struct inode *inode = NULL;
1227         struct inode_security_struct *isec;
1228         char **names = NULL, *page;
1229         int num;
1230         int *values = NULL;
1231         u32 sid;
1232
1233         /* remove any existing files */
1234         for (i = 0; i < bool_num; i++)
1235                 kfree(bool_pending_names[i]);
1236         kfree(bool_pending_names);
1237         kfree(bool_pending_values);
1238         bool_pending_names = NULL;
1239         bool_pending_values = NULL;
1240
1241         sel_remove_entries(dir);
1242
1243         ret = -ENOMEM;
1244         page = (char *)get_zeroed_page(GFP_KERNEL);
1245         if (!page)
1246                 goto out;
1247
1248         ret = security_get_bools(&num, &names, &values);
1249         if (ret)
1250                 goto out;
1251
1252         for (i = 0; i < num; i++) {
1253                 ret = -ENOMEM;
1254                 dentry = d_alloc_name(dir, names[i]);
1255                 if (!dentry)
1256                         goto out;
1257
1258                 ret = -ENOMEM;
1259                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1260                 if (!inode)
1261                         goto out;
1262
1263                 ret = -EINVAL;
1264                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1265                 if (len < 0)
1266                         goto out;
1267
1268                 ret = -ENAMETOOLONG;
1269                 if (len >= PAGE_SIZE)
1270                         goto out;
1271
1272                 isec = (struct inode_security_struct *)inode->i_security;
1273                 ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid);
1274                 if (ret)
1275                         goto out;
1276
1277                 isec->sid = sid;
1278                 isec->initialized = 1;
1279                 inode->i_fop = &sel_bool_ops;
1280                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1281                 d_add(dentry, inode);
1282         }
1283         bool_num = num;
1284         bool_pending_names = names;
1285         bool_pending_values = values;
1286
1287         free_page((unsigned long)page);
1288         return 0;
1289 out:
1290         free_page((unsigned long)page);
1291
1292         if (names) {
1293                 for (i = 0; i < num; i++)
1294                         kfree(names[i]);
1295                 kfree(names);
1296         }
1297         kfree(values);
1298         sel_remove_entries(dir);
1299
1300         return ret;
1301 }
1302
1303 #define NULL_FILE_NAME "null"
1304
1305 struct dentry *selinux_null;
1306
1307 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1308                                             size_t count, loff_t *ppos)
1309 {
1310         char tmpbuf[TMPBUFLEN];
1311         ssize_t length;
1312
1313         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1314         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1315 }
1316
1317 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1318                                              const char __user *buf,
1319                                              size_t count, loff_t *ppos)
1320
1321 {
1322         char *page = NULL;
1323         ssize_t ret;
1324         int new_value;
1325
1326         ret = task_has_security(current, SECURITY__SETSECPARAM);
1327         if (ret)
1328                 goto out;
1329
1330         ret = -ENOMEM;
1331         if (count >= PAGE_SIZE)
1332                 goto out;
1333
1334         /* No partial writes. */
1335         ret = -EINVAL;
1336         if (*ppos != 0)
1337                 goto out;
1338
1339         ret = -ENOMEM;
1340         page = (char *)get_zeroed_page(GFP_KERNEL);
1341         if (!page)
1342                 goto out;
1343
1344         ret = -EFAULT;
1345         if (copy_from_user(page, buf, count))
1346                 goto out;
1347
1348         ret = -EINVAL;
1349         if (sscanf(page, "%u", &new_value) != 1)
1350                 goto out;
1351
1352         avc_cache_threshold = new_value;
1353
1354         ret = count;
1355 out:
1356         free_page((unsigned long)page);
1357         return ret;
1358 }
1359
1360 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1361                                        size_t count, loff_t *ppos)
1362 {
1363         char *page;
1364         ssize_t length;
1365
1366         page = (char *)__get_free_page(GFP_KERNEL);
1367         if (!page)
1368                 return -ENOMEM;
1369
1370         length = avc_get_hash_stats(page);
1371         if (length >= 0)
1372                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1373         free_page((unsigned long)page);
1374
1375         return length;
1376 }
1377
1378 static const struct file_operations sel_avc_cache_threshold_ops = {
1379         .read           = sel_read_avc_cache_threshold,
1380         .write          = sel_write_avc_cache_threshold,
1381         .llseek         = generic_file_llseek,
1382 };
1383
1384 static const struct file_operations sel_avc_hash_stats_ops = {
1385         .read           = sel_read_avc_hash_stats,
1386         .llseek         = generic_file_llseek,
1387 };
1388
1389 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1390 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1391 {
1392         int cpu;
1393
1394         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1395                 if (!cpu_possible(cpu))
1396                         continue;
1397                 *idx = cpu + 1;
1398                 return &per_cpu(avc_cache_stats, cpu);
1399         }
1400         return NULL;
1401 }
1402
1403 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1404 {
1405         loff_t n = *pos - 1;
1406
1407         if (*pos == 0)
1408                 return SEQ_START_TOKEN;
1409
1410         return sel_avc_get_stat_idx(&n);
1411 }
1412
1413 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1414 {
1415         return sel_avc_get_stat_idx(pos);
1416 }
1417
1418 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1419 {
1420         struct avc_cache_stats *st = v;
1421
1422         if (v == SEQ_START_TOKEN)
1423                 seq_printf(seq, "lookups hits misses allocations reclaims "
1424                            "frees\n");
1425         else {
1426                 unsigned int lookups = st->lookups;
1427                 unsigned int misses = st->misses;
1428                 unsigned int hits = lookups - misses;
1429                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1430                            hits, misses, st->allocations,
1431                            st->reclaims, st->frees);
1432         }
1433         return 0;
1434 }
1435
1436 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1437 { }
1438
1439 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1440         .start          = sel_avc_stats_seq_start,
1441         .next           = sel_avc_stats_seq_next,
1442         .show           = sel_avc_stats_seq_show,
1443         .stop           = sel_avc_stats_seq_stop,
1444 };
1445
1446 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1447 {
1448         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1449 }
1450
1451 static const struct file_operations sel_avc_cache_stats_ops = {
1452         .open           = sel_open_avc_cache_stats,
1453         .read           = seq_read,
1454         .llseek         = seq_lseek,
1455         .release        = seq_release,
1456 };
1457 #endif
1458
1459 static int sel_make_avc_files(struct dentry *dir)
1460 {
1461         int i;
1462         static struct tree_descr files[] = {
1463                 { "cache_threshold",
1464                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1465                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1466 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1467                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1468 #endif
1469         };
1470
1471         for (i = 0; i < ARRAY_SIZE(files); i++) {
1472                 struct inode *inode;
1473                 struct dentry *dentry;
1474
1475                 dentry = d_alloc_name(dir, files[i].name);
1476                 if (!dentry)
1477                         return -ENOMEM;
1478
1479                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1480                 if (!inode)
1481                         return -ENOMEM;
1482
1483                 inode->i_fop = files[i].ops;
1484                 inode->i_ino = ++sel_last_ino;
1485                 d_add(dentry, inode);
1486         }
1487
1488         return 0;
1489 }
1490
1491 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1492                                 size_t count, loff_t *ppos)
1493 {
1494         struct inode *inode;
1495         char *con;
1496         u32 sid, len;
1497         ssize_t ret;
1498
1499         inode = file->f_path.dentry->d_inode;
1500         sid = inode->i_ino&SEL_INO_MASK;
1501         ret = security_sid_to_context(sid, &con, &len);
1502         if (ret)
1503                 return ret;
1504
1505         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1506         kfree(con);
1507         return ret;
1508 }
1509
1510 static const struct file_operations sel_initcon_ops = {
1511         .read           = sel_read_initcon,
1512         .llseek         = generic_file_llseek,
1513 };
1514
1515 static int sel_make_initcon_files(struct dentry *dir)
1516 {
1517         int i;
1518
1519         for (i = 1; i <= SECINITSID_NUM; i++) {
1520                 struct inode *inode;
1521                 struct dentry *dentry;
1522                 dentry = d_alloc_name(dir, security_get_initial_sid_context(i));
1523                 if (!dentry)
1524                         return -ENOMEM;
1525
1526                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1527                 if (!inode)
1528                         return -ENOMEM;
1529
1530                 inode->i_fop = &sel_initcon_ops;
1531                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1532                 d_add(dentry, inode);
1533         }
1534
1535         return 0;
1536 }
1537
1538 static inline unsigned int sel_div(unsigned long a, unsigned long b)
1539 {
1540         return a / b - (a % b < 0);
1541 }
1542
1543 static inline unsigned long sel_class_to_ino(u16 class)
1544 {
1545         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1546 }
1547
1548 static inline u16 sel_ino_to_class(unsigned long ino)
1549 {
1550         return sel_div(ino & SEL_INO_MASK, SEL_VEC_MAX + 1);
1551 }
1552
1553 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1554 {
1555         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1556 }
1557
1558 static inline u32 sel_ino_to_perm(unsigned long ino)
1559 {
1560         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1561 }
1562
1563 static ssize_t sel_read_class(struct file *file, char __user *buf,
1564                                 size_t count, loff_t *ppos)
1565 {
1566         ssize_t rc, len;
1567         char *page;
1568         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1569
1570         page = (char *)__get_free_page(GFP_KERNEL);
1571         if (!page)
1572                 return -ENOMEM;
1573
1574         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_class(ino));
1575         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1576         free_page((unsigned long)page);
1577
1578         return rc;
1579 }
1580
1581 static const struct file_operations sel_class_ops = {
1582         .read           = sel_read_class,
1583         .llseek         = generic_file_llseek,
1584 };
1585
1586 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1587                                 size_t count, loff_t *ppos)
1588 {
1589         ssize_t rc, len;
1590         char *page;
1591         unsigned long ino = file->f_path.dentry->d_inode->i_ino;
1592
1593         page = (char *)__get_free_page(GFP_KERNEL);
1594         if (!page)
1595                 return -ENOMEM;
1596
1597         len = snprintf(page, PAGE_SIZE, "%d", sel_ino_to_perm(ino));
1598         rc = simple_read_from_buffer(buf, count, ppos, page, len);
1599         free_page((unsigned long)page);
1600
1601         return rc;
1602 }
1603
1604 static const struct file_operations sel_perm_ops = {
1605         .read           = sel_read_perm,
1606         .llseek         = generic_file_llseek,
1607 };
1608
1609 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1610                                   size_t count, loff_t *ppos)
1611 {
1612         int value;
1613         char tmpbuf[TMPBUFLEN];
1614         ssize_t length;
1615         unsigned long i_ino = file->f_path.dentry->d_inode->i_ino;
1616
1617         value = security_policycap_supported(i_ino & SEL_INO_MASK);
1618         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1619
1620         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1621 }
1622
1623 static const struct file_operations sel_policycap_ops = {
1624         .read           = sel_read_policycap,
1625         .llseek         = generic_file_llseek,
1626 };
1627
1628 static int sel_make_perm_files(char *objclass, int classvalue,
1629                                 struct dentry *dir)
1630 {
1631         int i, rc, nperms;
1632         char **perms;
1633
1634         rc = security_get_permissions(objclass, &perms, &nperms);
1635         if (rc)
1636                 return rc;
1637
1638         for (i = 0; i < nperms; i++) {
1639                 struct inode *inode;
1640                 struct dentry *dentry;
1641
1642                 rc = -ENOMEM;
1643                 dentry = d_alloc_name(dir, perms[i]);
1644                 if (!dentry)
1645                         goto out;
1646
1647                 rc = -ENOMEM;
1648                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1649                 if (!inode)
1650                         goto out;
1651
1652                 inode->i_fop = &sel_perm_ops;
1653                 /* i+1 since perm values are 1-indexed */
1654                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1655                 d_add(dentry, inode);
1656         }
1657         rc = 0;
1658 out:
1659         for (i = 0; i < nperms; i++)
1660                 kfree(perms[i]);
1661         kfree(perms);
1662         return rc;
1663 }
1664
1665 static int sel_make_class_dir_entries(char *classname, int index,
1666                                         struct dentry *dir)
1667 {
1668         struct dentry *dentry = NULL;
1669         struct inode *inode = NULL;
1670         int rc;
1671
1672         dentry = d_alloc_name(dir, "index");
1673         if (!dentry)
1674                 return -ENOMEM;
1675
1676         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1677         if (!inode)
1678                 return -ENOMEM;
1679
1680         inode->i_fop = &sel_class_ops;
1681         inode->i_ino = sel_class_to_ino(index);
1682         d_add(dentry, inode);
1683
1684         dentry = d_alloc_name(dir, "perms");
1685         if (!dentry)
1686                 return -ENOMEM;
1687
1688         rc = sel_make_dir(dir->d_inode, dentry, &last_class_ino);
1689         if (rc)
1690                 return rc;
1691
1692         rc = sel_make_perm_files(classname, index, dentry);
1693
1694         return rc;
1695 }
1696
1697 static void sel_remove_classes(void)
1698 {
1699         struct list_head *class_node;
1700
1701         list_for_each(class_node, &class_dir->d_subdirs) {
1702                 struct dentry *class_subdir = list_entry(class_node,
1703                                         struct dentry, d_u.d_child);
1704                 struct list_head *class_subdir_node;
1705
1706                 list_for_each(class_subdir_node, &class_subdir->d_subdirs) {
1707                         struct dentry *d = list_entry(class_subdir_node,
1708                                                 struct dentry, d_u.d_child);
1709
1710                         if (d->d_inode)
1711                                 if (d->d_inode->i_mode & S_IFDIR)
1712                                         sel_remove_entries(d);
1713                 }
1714
1715                 sel_remove_entries(class_subdir);
1716         }
1717
1718         sel_remove_entries(class_dir);
1719 }
1720
1721 static int sel_make_classes(void)
1722 {
1723         int rc, nclasses, i;
1724         char **classes;
1725
1726         /* delete any existing entries */
1727         sel_remove_classes();
1728
1729         rc = security_get_classes(&classes, &nclasses);
1730         if (rc)
1731                 return rc;
1732
1733         /* +2 since classes are 1-indexed */
1734         last_class_ino = sel_class_to_ino(nclasses + 2);
1735
1736         for (i = 0; i < nclasses; i++) {
1737                 struct dentry *class_name_dir;
1738
1739                 rc = -ENOMEM;
1740                 class_name_dir = d_alloc_name(class_dir, classes[i]);
1741                 if (!class_name_dir)
1742                         goto out;
1743
1744                 rc = sel_make_dir(class_dir->d_inode, class_name_dir,
1745                                 &last_class_ino);
1746                 if (rc)
1747                         goto out;
1748
1749                 /* i+1 since class values are 1-indexed */
1750                 rc = sel_make_class_dir_entries(classes[i], i + 1,
1751                                 class_name_dir);
1752                 if (rc)
1753                         goto out;
1754         }
1755         rc = 0;
1756 out:
1757         for (i = 0; i < nclasses; i++)
1758                 kfree(classes[i]);
1759         kfree(classes);
1760         return rc;
1761 }
1762
1763 static int sel_make_policycap(void)
1764 {
1765         unsigned int iter;
1766         struct dentry *dentry = NULL;
1767         struct inode *inode = NULL;
1768
1769         sel_remove_entries(policycap_dir);
1770
1771         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1772                 if (iter < ARRAY_SIZE(policycap_names))
1773                         dentry = d_alloc_name(policycap_dir,
1774                                               policycap_names[iter]);
1775                 else
1776                         dentry = d_alloc_name(policycap_dir, "unknown");
1777
1778                 if (dentry == NULL)
1779                         return -ENOMEM;
1780
1781                 inode = sel_make_inode(policycap_dir->d_sb, S_IFREG | S_IRUGO);
1782                 if (inode == NULL)
1783                         return -ENOMEM;
1784
1785                 inode->i_fop = &sel_policycap_ops;
1786                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1787                 d_add(dentry, inode);
1788         }
1789
1790         return 0;
1791 }
1792
1793 static int sel_make_dir(struct inode *dir, struct dentry *dentry,
1794                         unsigned long *ino)
1795 {
1796         struct inode *inode;
1797
1798         inode = sel_make_inode(dir->i_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1799         if (!inode)
1800                 return -ENOMEM;
1801
1802         inode->i_op = &simple_dir_inode_operations;
1803         inode->i_fop = &simple_dir_operations;
1804         inode->i_ino = ++(*ino);
1805         /* directory inodes start off with i_nlink == 2 (for "." entry) */
1806         inc_nlink(inode);
1807         d_add(dentry, inode);
1808         /* bump link count on parent directory, too */
1809         inc_nlink(dir);
1810
1811         return 0;
1812 }
1813
1814 static int sel_fill_super(struct super_block *sb, void *data, int silent)
1815 {
1816         int ret;
1817         struct dentry *dentry;
1818         struct inode *inode, *root_inode;
1819         struct inode_security_struct *isec;
1820
1821         static struct tree_descr selinux_files[] = {
1822                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1823                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1824                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1825                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1826                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1827                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1828                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1829                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1830                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1831                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1832                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1833                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1834                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1835                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1836                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
1837                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
1838                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUSR},
1839                 /* last one */ {""}
1840         };
1841         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1842         if (ret)
1843                 goto err;
1844
1845         root_inode = sb->s_root->d_inode;
1846
1847         ret = -ENOMEM;
1848         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1849         if (!dentry)
1850                 goto err;
1851
1852         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1853         if (ret)
1854                 goto err;
1855
1856         bool_dir = dentry;
1857
1858         ret = -ENOMEM;
1859         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1860         if (!dentry)
1861                 goto err;
1862
1863         ret = -ENOMEM;
1864         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1865         if (!inode)
1866                 goto err;
1867
1868         inode->i_ino = ++sel_last_ino;
1869         isec = (struct inode_security_struct *)inode->i_security;
1870         isec->sid = SECINITSID_DEVNULL;
1871         isec->sclass = SECCLASS_CHR_FILE;
1872         isec->initialized = 1;
1873
1874         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1875         d_add(dentry, inode);
1876         selinux_null = dentry;
1877
1878         ret = -ENOMEM;
1879         dentry = d_alloc_name(sb->s_root, "avc");
1880         if (!dentry)
1881                 goto err;
1882
1883         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1884         if (ret)
1885                 goto err;
1886
1887         ret = sel_make_avc_files(dentry);
1888         if (ret)
1889                 goto err;
1890
1891         ret = -ENOMEM;
1892         dentry = d_alloc_name(sb->s_root, "initial_contexts");
1893         if (!dentry)
1894                 goto err;
1895
1896         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1897         if (ret)
1898                 goto err;
1899
1900         ret = sel_make_initcon_files(dentry);
1901         if (ret)
1902                 goto err;
1903
1904         ret = -ENOMEM;
1905         dentry = d_alloc_name(sb->s_root, "class");
1906         if (!dentry)
1907                 goto err;
1908
1909         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1910         if (ret)
1911                 goto err;
1912
1913         class_dir = dentry;
1914
1915         ret = -ENOMEM;
1916         dentry = d_alloc_name(sb->s_root, "policy_capabilities");
1917         if (!dentry)
1918                 goto err;
1919
1920         ret = sel_make_dir(root_inode, dentry, &sel_last_ino);
1921         if (ret)
1922                 goto err;
1923
1924         policycap_dir = dentry;
1925
1926         return 0;
1927 err:
1928         printk(KERN_ERR "SELinux: %s:  failed while creating inodes\n",
1929                 __func__);
1930         return ret;
1931 }
1932
1933 static struct dentry *sel_mount(struct file_system_type *fs_type,
1934                       int flags, const char *dev_name, void *data)
1935 {
1936         return mount_single(fs_type, flags, data, sel_fill_super);
1937 }
1938
1939 static struct file_system_type sel_fs_type = {
1940         .name           = "selinuxfs",
1941         .mount          = sel_mount,
1942         .kill_sb        = kill_litter_super,
1943 };
1944
1945 struct vfsmount *selinuxfs_mount;
1946 static struct kobject *selinuxfs_kobj;
1947
1948 static int __init init_sel_fs(void)
1949 {
1950         int err;
1951
1952         if (!selinux_enabled)
1953                 return 0;
1954
1955         selinuxfs_kobj = kobject_create_and_add("selinux", fs_kobj);
1956         if (!selinuxfs_kobj)
1957                 return -ENOMEM;
1958
1959         err = register_filesystem(&sel_fs_type);
1960         if (err) {
1961                 kobject_put(selinuxfs_kobj);
1962                 return err;
1963         }
1964
1965         selinuxfs_mount = kern_mount(&sel_fs_type);
1966         if (IS_ERR(selinuxfs_mount)) {
1967                 printk(KERN_ERR "selinuxfs:  could not mount!\n");
1968                 err = PTR_ERR(selinuxfs_mount);
1969                 selinuxfs_mount = NULL;
1970         }
1971
1972         return err;
1973 }
1974
1975 __initcall(init_sel_fs);
1976
1977 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1978 void exit_sel_fs(void)
1979 {
1980         kobject_put(selinuxfs_kobj);
1981         kern_unmount(selinuxfs_mount);
1982         unregister_filesystem(&sel_fs_type);
1983 }
1984 #endif