security/selinux/selinuxfs.c

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