security/selinux/selinuxfs.c

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