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/config.h>
  13 #include <linux/kernel.h>
  14 #include <linux/pagemap.h>
  15 #include <linux/slab.h>
  16 #include <linux/vmalloc.h>
  17 #include <linux/fs.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 <asm/uaccess.h>
  25 #include <asm/semaphore.h>
  26
  27 /* selinuxfs pseudo filesystem for exporting the security policy API.
  28    Based on the proc code and the fs/nfsd/nfsctl.c code. */
  29
  30 #include "flask.h"
  31 #include "avc.h"
  32 #include "avc_ss.h"
  33 #include "security.h"
  34 #include "objsec.h"
  35 #include "conditional.h"
  36
  37 unsigned int selinux_checkreqprot = CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
  38
  39 static int __init checkreqprot_setup(char *str)
  40 {
  41         selinux_checkreqprot = simple_strtoul(str,NULL,0) ? 1 : 0;
  42         return 1;
  43 }
  44 __setup("checkreqprot=", checkreqprot_setup);
  45
  46
  47 static DECLARE_MUTEX(sel_sem);
  48
  49 /* global data for booleans */
  50 static struct dentry *bool_dir = NULL;
  51 static int bool_num = 0;
  52 static int *bool_pending_values = NULL;
  53
  54 extern void selnl_notify_setenforce(int val);
  55
  56 /* Check whether a task is allowed to use a security operation. */
  57 static int task_has_security(struct task_struct *tsk,
  58                              u32 perms)
  59 {
  60         struct task_security_struct *tsec;
  61
  62         tsec = tsk->security;
  63         if (!tsec)
  64                 return -EACCES;
  65
  66         return avc_has_perm(tsec->sid, SECINITSID_SECURITY,
  67                             SECCLASS_SECURITY, perms, NULL);
  68 }
  69
  70 enum sel_inos {
  71         SEL_ROOT_INO = 2,
  72         SEL_LOAD,       /* load policy */
  73         SEL_ENFORCE,    /* get or set enforcing status */
  74         SEL_CONTEXT,    /* validate context */
  75         SEL_ACCESS,     /* compute access decision */
  76         SEL_CREATE,     /* compute create labeling decision */
  77         SEL_RELABEL,    /* compute relabeling decision */
  78         SEL_USER,       /* compute reachable user contexts */
  79         SEL_POLICYVERS, /* return policy version for this kernel */
  80         SEL_COMMIT_BOOLS, /* commit new boolean values */
  81         SEL_MLS,        /* return if MLS policy is enabled */
  82         SEL_DISABLE,    /* disable SELinux until next reboot */
  83         SEL_AVC,        /* AVC management directory */
  84         SEL_MEMBER,     /* compute polyinstantiation membership decision */
  85         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
  86 };
  87
  88 #define TMPBUFLEN       12
  89 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
  90                                 size_t count, loff_t *ppos)
  91 {
  92         char tmpbuf[TMPBUFLEN];
  93         ssize_t length;
  94
  95         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_enforcing);
  96         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
  97 }
  98
  99 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 100 static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
 101                                  size_t count, loff_t *ppos)
 102
 103 {
 104         char *page;
 105         ssize_t length;
 106         int new_value;
 107
 108         if (count < 0 || count >= PAGE_SIZE)
 109                 return -ENOMEM;
 110         if (*ppos != 0) {
 111                 /* No partial writes. */
 112                 return -EINVAL;
 113         }
 114         page = (char*)get_zeroed_page(GFP_KERNEL);
 115         if (!page)
 116                 return -ENOMEM;
 117         length = -EFAULT;
 118         if (copy_from_user(page, buf, count))
 119                 goto out;
 120
 121         length = -EINVAL;
 122         if (sscanf(page, "%d", &new_value) != 1)
 123                 goto out;
 124
 125         if (new_value != selinux_enforcing) {
 126                 length = task_has_security(current, SECURITY__SETENFORCE);
 127                 if (length)
 128                         goto out;
 129                 selinux_enforcing = new_value;
 130                 if (selinux_enforcing)
 131                         avc_ss_reset(0);
 132                 selnl_notify_setenforce(selinux_enforcing);
 133         }
 134         length = count;
 135 out:
 136         free_page((unsigned long) page);
 137         return length;
 138 }
 139 #else
 140 #define sel_write_enforce NULL
 141 #endif
 142
 143 static struct file_operations sel_enforce_ops = {
 144         .read           = sel_read_enforce,
 145         .write          = sel_write_enforce,
 146 };
 147
 148 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 149 static ssize_t sel_write_disable(struct file * file, const char __user * buf,
 150                                  size_t count, loff_t *ppos)
 151
 152 {
 153         char *page;
 154         ssize_t length;
 155         int new_value;
 156         extern int selinux_disable(void);
 157
 158         if (count < 0 || count >= PAGE_SIZE)
 159                 return -ENOMEM;
 160         if (*ppos != 0) {
 161                 /* No partial writes. */
 162                 return -EINVAL;
 163         }
 164         page = (char*)get_zeroed_page(GFP_KERNEL);
 165         if (!page)
 166                 return -ENOMEM;
 167         length = -EFAULT;
 168         if (copy_from_user(page, buf, count))
 169                 goto out;
 170
 171         length = -EINVAL;
 172         if (sscanf(page, "%d", &new_value) != 1)
 173                 goto out;
 174
 175         if (new_value) {
 176                 length = selinux_disable();
 177                 if (length < 0)
 178                         goto out;
 179         }
 180
 181         length = count;
 182 out:
 183         free_page((unsigned long) page);
 184         return length;
 185 }
 186 #else
 187 #define sel_write_disable NULL
 188 #endif
 189
 190 static struct file_operations sel_disable_ops = {
 191         .write          = sel_write_disable,
 192 };
 193
 194 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 195                                    size_t count, loff_t *ppos)
 196 {
 197         char tmpbuf[TMPBUFLEN];
 198         ssize_t length;
 199
 200         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 201         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 202 }
 203
 204 static struct file_operations sel_policyvers_ops = {
 205         .read           = sel_read_policyvers,
 206 };
 207
 208 /* declaration for sel_write_load */
 209 static int sel_make_bools(void);
 210
 211 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 212                                 size_t count, loff_t *ppos)
 213 {
 214         char tmpbuf[TMPBUFLEN];
 215         ssize_t length;
 216
 217         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", selinux_mls_enabled);
 218         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 219 }
 220
 221 static struct file_operations sel_mls_ops = {
 222         .read           = sel_read_mls,
 223 };
 224
 225 static ssize_t sel_write_load(struct file * file, const char __user * buf,
 226                               size_t count, loff_t *ppos)
 227
 228 {
 229         int ret;
 230         ssize_t length;
 231         void *data = NULL;
 232
 233         down(&sel_sem);
 234
 235         length = task_has_security(current, SECURITY__LOAD_POLICY);
 236         if (length)
 237                 goto out;
 238
 239         if (*ppos != 0) {
 240                 /* No partial writes. */
 241                 length = -EINVAL;
 242                 goto out;
 243         }
 244
 245         if ((count < 0) || (count > 64 * 1024 * 1024)
 246             || (data = vmalloc(count)) == NULL) {
 247                 length = -ENOMEM;
 248                 goto out;
 249         }
 250
 251         length = -EFAULT;
 252         if (copy_from_user(data, buf, count) != 0)
 253                 goto out;
 254
 255         length = security_load_policy(data, count);
 256         if (length)
 257                 goto out;
 258
 259         ret = sel_make_bools();
 260         if (ret)
 261                 length = ret;
 262         else
 263                 length = count;
 264 out:
 265         up(&sel_sem);
 266         vfree(data);
 267         return length;
 268 }
 269
 270 static struct file_operations sel_load_ops = {
 271         .write          = sel_write_load,
 272 };
 273
 274
 275 static ssize_t sel_write_context(struct file * file, const char __user * buf,
 276                                  size_t count, loff_t *ppos)
 277
 278 {
 279         char *page;
 280         u32 sid;
 281         ssize_t length;
 282
 283         length = task_has_security(current, SECURITY__CHECK_CONTEXT);
 284         if (length)
 285                 return length;
 286
 287         if (count < 0 || count >= PAGE_SIZE)
 288                 return -ENOMEM;
 289         if (*ppos != 0) {
 290                 /* No partial writes. */
 291                 return -EINVAL;
 292         }
 293         page = (char*)get_zeroed_page(GFP_KERNEL);
 294         if (!page)
 295                 return -ENOMEM;
 296         length = -EFAULT;
 297         if (copy_from_user(page, buf, count))
 298                 goto out;
 299
 300         length = security_context_to_sid(page, count, &sid);
 301         if (length < 0)
 302                 goto out;
 303
 304         length = count;
 305 out:
 306         free_page((unsigned long) page);
 307         return length;
 308 }
 309
 310 static struct file_operations sel_context_ops = {
 311         .write          = sel_write_context,
 312 };
 313
 314 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 315                                      size_t count, loff_t *ppos)
 316 {
 317         char tmpbuf[TMPBUFLEN];
 318         ssize_t length;
 319
 320         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", selinux_checkreqprot);
 321         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 322 }
 323
 324 static ssize_t sel_write_checkreqprot(struct file * file, const char __user * buf,
 325                                       size_t count, loff_t *ppos)
 326 {
 327         char *page;
 328         ssize_t length;
 329         unsigned int new_value;
 330
 331         length = task_has_security(current, SECURITY__SETCHECKREQPROT);
 332         if (length)
 333                 return length;
 334
 335         if (count < 0 || count >= PAGE_SIZE)
 336                 return -ENOMEM;
 337         if (*ppos != 0) {
 338                 /* No partial writes. */
 339                 return -EINVAL;
 340         }
 341         page = (char*)get_zeroed_page(GFP_KERNEL);
 342         if (!page)
 343                 return -ENOMEM;
 344         length = -EFAULT;
 345         if (copy_from_user(page, buf, count))
 346                 goto out;
 347
 348         length = -EINVAL;
 349         if (sscanf(page, "%u", &new_value) != 1)
 350                 goto out;
 351
 352         selinux_checkreqprot = new_value ? 1 : 0;
 353         length = count;
 354 out:
 355         free_page((unsigned long) page);
 356         return length;
 357 }
 358 static struct file_operations sel_checkreqprot_ops = {
 359         .read           = sel_read_checkreqprot,
 360         .write          = sel_write_checkreqprot,
 361 };
 362
 363 /*
 364  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 365  */
 366 static ssize_t sel_write_access(struct file * file, char *buf, size_t size);
 367 static ssize_t sel_write_create(struct file * file, char *buf, size_t size);
 368 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size);
 369 static ssize_t sel_write_user(struct file * file, char *buf, size_t size);
 370 static ssize_t sel_write_member(struct file * file, char *buf, size_t size);
 371
 372 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 373         [SEL_ACCESS] = sel_write_access,
 374         [SEL_CREATE] = sel_write_create,
 375         [SEL_RELABEL] = sel_write_relabel,
 376         [SEL_USER] = sel_write_user,
 377         [SEL_MEMBER] = sel_write_member,
 378 };
 379
 380 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 381 {
 382         ino_t ino =  file->f_dentry->d_inode->i_ino;
 383         char *data;
 384         ssize_t rv;
 385
 386         if (ino >= sizeof(write_op)/sizeof(write_op[0]) || !write_op[ino])
 387                 return -EINVAL;
 388
 389         data = simple_transaction_get(file, buf, size);
 390         if (IS_ERR(data))
 391                 return PTR_ERR(data);
 392
 393         rv =  write_op[ino](file, data, size);
 394         if (rv>0) {
 395                 simple_transaction_set(file, rv);
 396                 rv = size;
 397         }
 398         return rv;
 399 }
 400
 401 static struct file_operations transaction_ops = {
 402         .write          = selinux_transaction_write,
 403         .read           = simple_transaction_read,
 404         .release        = simple_transaction_release,
 405 };
 406
 407 /*
 408  * payload - write methods
 409  * If the method has a response, the response should be put in buf,
 410  * and the length returned.  Otherwise return 0 or and -error.
 411  */
 412
 413 static ssize_t sel_write_access(struct file * file, char *buf, size_t size)
 414 {
 415         char *scon, *tcon;
 416         u32 ssid, tsid;
 417         u16 tclass;
 418         u32 req;
 419         struct av_decision avd;
 420         ssize_t length;
 421
 422         length = task_has_security(current, SECURITY__COMPUTE_AV);
 423         if (length)
 424                 return length;
 425
 426         length = -ENOMEM;
 427         scon = kmalloc(size+1, GFP_KERNEL);
 428         if (!scon)
 429                 return length;
 430         memset(scon, 0, size+1);
 431
 432         tcon = kmalloc(size+1, GFP_KERNEL);
 433         if (!tcon)
 434                 goto out;
 435         memset(tcon, 0, size+1);
 436
 437         length = -EINVAL;
 438         if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
 439                 goto out2;
 440
 441         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 442         if (length < 0)
 443                 goto out2;
 444         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 445         if (length < 0)
 446                 goto out2;
 447
 448         length = security_compute_av(ssid, tsid, tclass, req, &avd);
 449         if (length < 0)
 450                 goto out2;
 451
 452         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 453                           "%x %x %x %x %u",
 454                           avd.allowed, avd.decided,
 455                           avd.auditallow, avd.auditdeny,
 456                           avd.seqno);
 457 out2:
 458         kfree(tcon);
 459 out:
 460         kfree(scon);
 461         return length;
 462 }
 463
 464 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
 465 {
 466         char *scon, *tcon;
 467         u32 ssid, tsid, newsid;
 468         u16 tclass;
 469         ssize_t length;
 470         char *newcon;
 471         u32 len;
 472
 473         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 474         if (length)
 475                 return length;
 476
 477         length = -ENOMEM;
 478         scon = kmalloc(size+1, GFP_KERNEL);
 479         if (!scon)
 480                 return length;
 481         memset(scon, 0, size+1);
 482
 483         tcon = kmalloc(size+1, GFP_KERNEL);
 484         if (!tcon)
 485                 goto out;
 486         memset(tcon, 0, size+1);
 487
 488         length = -EINVAL;
 489         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 490                 goto out2;
 491
 492         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 493         if (length < 0)
 494                 goto out2;
 495         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 496         if (length < 0)
 497                 goto out2;
 498
 499         length = security_transition_sid(ssid, tsid, tclass, &newsid);
 500         if (length < 0)
 501                 goto out2;
 502
 503         length = security_sid_to_context(newsid, &newcon, &len);
 504         if (length < 0)
 505                 goto out2;
 506
 507         if (len > SIMPLE_TRANSACTION_LIMIT) {
 508                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
 509                        "max\n", __FUNCTION__, len);
 510                 length = -ERANGE;
 511                 goto out3;
 512         }
 513
 514         memcpy(buf, newcon, len);
 515         length = len;
 516 out3:
 517         kfree(newcon);
 518 out2:
 519         kfree(tcon);
 520 out:
 521         kfree(scon);
 522         return length;
 523 }
 524
 525 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
 526 {
 527         char *scon, *tcon;
 528         u32 ssid, tsid, newsid;
 529         u16 tclass;
 530         ssize_t length;
 531         char *newcon;
 532         u32 len;
 533
 534         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 535         if (length)
 536                 return length;
 537
 538         length = -ENOMEM;
 539         scon = kmalloc(size+1, GFP_KERNEL);
 540         if (!scon)
 541                 return length;
 542         memset(scon, 0, size+1);
 543
 544         tcon = kmalloc(size+1, GFP_KERNEL);
 545         if (!tcon)
 546                 goto out;
 547         memset(tcon, 0, size+1);
 548
 549         length = -EINVAL;
 550         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 551                 goto out2;
 552
 553         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 554         if (length < 0)
 555                 goto out2;
 556         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 557         if (length < 0)
 558                 goto out2;
 559
 560         length = security_change_sid(ssid, tsid, tclass, &newsid);
 561         if (length < 0)
 562                 goto out2;
 563
 564         length = security_sid_to_context(newsid, &newcon, &len);
 565         if (length < 0)
 566                 goto out2;
 567
 568         if (len > SIMPLE_TRANSACTION_LIMIT) {
 569                 length = -ERANGE;
 570                 goto out3;
 571         }
 572
 573         memcpy(buf, newcon, len);
 574         length = len;
 575 out3:
 576         kfree(newcon);
 577 out2:
 578         kfree(tcon);
 579 out:
 580         kfree(scon);
 581         return length;
 582 }
 583
 584 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
 585 {
 586         char *con, *user, *ptr;
 587         u32 sid, *sids;
 588         ssize_t length;
 589         char *newcon;
 590         int i, rc;
 591         u32 len, nsids;
 592
 593         length = task_has_security(current, SECURITY__COMPUTE_USER);
 594         if (length)
 595                 return length;
 596
 597         length = -ENOMEM;
 598         con = kmalloc(size+1, GFP_KERNEL);
 599         if (!con)
 600                 return length;
 601         memset(con, 0, size+1);
 602
 603         user = kmalloc(size+1, GFP_KERNEL);
 604         if (!user)
 605                 goto out;
 606         memset(user, 0, size+1);
 607
 608         length = -EINVAL;
 609         if (sscanf(buf, "%s %s", con, user) != 2)
 610                 goto out2;
 611
 612         length = security_context_to_sid(con, strlen(con)+1, &sid);
 613         if (length < 0)
 614                 goto out2;
 615
 616         length = security_get_user_sids(sid, user, &sids, &nsids);
 617         if (length < 0)
 618                 goto out2;
 619
 620         length = sprintf(buf, "%u", nsids) + 1;
 621         ptr = buf + length;
 622         for (i = 0; i < nsids; i++) {
 623                 rc = security_sid_to_context(sids[i], &newcon, &len);
 624                 if (rc) {
 625                         length = rc;
 626                         goto out3;
 627                 }
 628                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
 629                         kfree(newcon);
 630                         length = -ERANGE;
 631                         goto out3;
 632                 }
 633                 memcpy(ptr, newcon, len);
 634                 kfree(newcon);
 635                 ptr += len;
 636                 length += len;
 637         }
 638 out3:
 639         kfree(sids);
 640 out2:
 641         kfree(user);
 642 out:
 643         kfree(con);
 644         return length;
 645 }
 646
 647 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
 648 {
 649         char *scon, *tcon;
 650         u32 ssid, tsid, newsid;
 651         u16 tclass;
 652         ssize_t length;
 653         char *newcon;
 654         u32 len;
 655
 656         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
 657         if (length)
 658                 return length;
 659
 660         length = -ENOMEM;
 661         scon = kmalloc(size+1, GFP_KERNEL);
 662         if (!scon)
 663                 return length;
 664         memset(scon, 0, size+1);
 665
 666         tcon = kmalloc(size+1, GFP_KERNEL);
 667         if (!tcon)
 668                 goto out;
 669         memset(tcon, 0, size+1);
 670
 671         length = -EINVAL;
 672         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 673                 goto out2;
 674
 675         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 676         if (length < 0)
 677                 goto out2;
 678         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 679         if (length < 0)
 680                 goto out2;
 681
 682         length = security_member_sid(ssid, tsid, tclass, &newsid);
 683         if (length < 0)
 684                 goto out2;
 685
 686         length = security_sid_to_context(newsid, &newcon, &len);
 687         if (length < 0)
 688                 goto out2;
 689
 690         if (len > SIMPLE_TRANSACTION_LIMIT) {
 691                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
 692                        "max\n", __FUNCTION__, len);
 693                 length = -ERANGE;
 694                 goto out3;
 695         }
 696
 697         memcpy(buf, newcon, len);
 698         length = len;
 699 out3:
 700         kfree(newcon);
 701 out2:
 702         kfree(tcon);
 703 out:
 704         kfree(scon);
 705         return length;
 706 }
 707
 708 static struct inode *sel_make_inode(struct super_block *sb, int mode)
 709 {
 710         struct inode *ret = new_inode(sb);
 711
 712         if (ret) {
 713                 ret->i_mode = mode;
 714                 ret->i_uid = ret->i_gid = 0;
 715                 ret->i_blksize = PAGE_CACHE_SIZE;
 716                 ret->i_blocks = 0;
 717                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
 718         }
 719         return ret;
 720 }
 721
 722 #define BOOL_INO_OFFSET 30
 723
 724 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
 725                              size_t count, loff_t *ppos)
 726 {
 727         char *page = NULL;
 728         ssize_t length;
 729         ssize_t end;
 730         ssize_t ret;
 731         int cur_enforcing;
 732         struct inode *inode;
 733
 734         down(&sel_sem);
 735
 736         ret = -EFAULT;
 737
 738         /* check to see if this file has been deleted */
 739         if (!filep->f_op)
 740                 goto out;
 741
 742         if (count < 0 || count > PAGE_SIZE) {
 743                 ret = -EINVAL;
 744                 goto out;
 745         }
 746         if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
 747                 ret = -ENOMEM;
 748                 goto out;
 749         }
 750
 751         inode = filep->f_dentry->d_inode;
 752         cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
 753         if (cur_enforcing < 0) {
 754                 ret = cur_enforcing;
 755                 goto out;
 756         }
 757
 758         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
 759                           bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
 760         if (length < 0) {
 761                 ret = length;
 762                 goto out;
 763         }
 764
 765         if (*ppos >= length) {
 766                 ret = 0;
 767                 goto out;
 768         }
 769         if (count + *ppos > length)
 770                 count = length - *ppos;
 771         end = count + *ppos;
 772         if (copy_to_user(buf, (char *) page + *ppos, count)) {
 773                 ret = -EFAULT;
 774                 goto out;
 775         }
 776         *ppos = end;
 777         ret = count;
 778 out:
 779         up(&sel_sem);
 780         if (page)
 781                 free_page((unsigned long)page);
 782         return ret;
 783 }
 784
 785 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
 786                               size_t count, loff_t *ppos)
 787 {
 788         char *page = NULL;
 789         ssize_t length = -EFAULT;
 790         int new_value;
 791         struct inode *inode;
 792
 793         down(&sel_sem);
 794
 795         length = task_has_security(current, SECURITY__SETBOOL);
 796         if (length)
 797                 goto out;
 798
 799         /* check to see if this file has been deleted */
 800         if (!filep->f_op)
 801                 goto out;
 802
 803         if (count < 0 || count >= PAGE_SIZE) {
 804                 length = -ENOMEM;
 805                 goto out;
 806         }
 807         if (*ppos != 0) {
 808                 /* No partial writes. */
 809                 goto out;
 810         }
 811         page = (char*)get_zeroed_page(GFP_KERNEL);
 812         if (!page) {
 813                 length = -ENOMEM;
 814                 goto out;
 815         }
 816
 817         if (copy_from_user(page, buf, count))
 818                 goto out;
 819
 820         length = -EINVAL;
 821         if (sscanf(page, "%d", &new_value) != 1)
 822                 goto out;
 823
 824         if (new_value)
 825                 new_value = 1;
 826
 827         inode = filep->f_dentry->d_inode;
 828         bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value;
 829         length = count;
 830
 831 out:
 832         up(&sel_sem);
 833         if (page)
 834                 free_page((unsigned long) page);
 835         return length;
 836 }
 837
 838 static struct file_operations sel_bool_ops = {
 839         .read           = sel_read_bool,
 840         .write          = sel_write_bool,
 841 };
 842
 843 static ssize_t sel_commit_bools_write(struct file *filep,
 844                                       const char __user *buf,
 845                                       size_t count, loff_t *ppos)
 846 {
 847         char *page = NULL;
 848         ssize_t length = -EFAULT;
 849         int new_value;
 850
 851         down(&sel_sem);
 852
 853         length = task_has_security(current, SECURITY__SETBOOL);
 854         if (length)
 855                 goto out;
 856
 857         /* check to see if this file has been deleted */
 858         if (!filep->f_op)
 859                 goto out;
 860
 861         if (count < 0 || count >= PAGE_SIZE) {
 862                 length = -ENOMEM;
 863                 goto out;
 864         }
 865         if (*ppos != 0) {
 866                 /* No partial writes. */
 867                 goto out;
 868         }
 869         page = (char*)get_zeroed_page(GFP_KERNEL);
 870         if (!page) {
 871                 length = -ENOMEM;
 872                 goto out;
 873         }
 874
 875         if (copy_from_user(page, buf, count))
 876                 goto out;
 877
 878         length = -EINVAL;
 879         if (sscanf(page, "%d", &new_value) != 1)
 880                 goto out;
 881
 882         if (new_value) {
 883                 security_set_bools(bool_num, bool_pending_values);
 884         }
 885
 886         length = count;
 887
 888 out:
 889         up(&sel_sem);
 890         if (page)
 891                 free_page((unsigned long) page);
 892         return length;
 893 }
 894
 895 static struct file_operations sel_commit_bools_ops = {
 896         .write          = sel_commit_bools_write,
 897 };
 898
 899 /* delete booleans - partial revoke() from
 900  * fs/proc/generic.c proc_kill_inodes */
 901 static void sel_remove_bools(struct dentry *de)
 902 {
 903         struct list_head *p, *node;
 904         struct super_block *sb = de->d_sb;
 905
 906         spin_lock(&dcache_lock);
 907         node = de->d_subdirs.next;
 908         while (node != &de->d_subdirs) {
 909                 struct dentry *d = list_entry(node, struct dentry, d_child);
 910                 list_del_init(node);
 911
 912                 if (d->d_inode) {
 913                         d = dget_locked(d);
 914                         spin_unlock(&dcache_lock);
 915                         d_delete(d);
 916                         simple_unlink(de->d_inode, d);
 917                         dput(d);
 918                         spin_lock(&dcache_lock);
 919                 }
 920                 node = de->d_subdirs.next;
 921         }
 922
 923         spin_unlock(&dcache_lock);
 924
 925         file_list_lock();
 926         list_for_each(p, &sb->s_files) {
 927                 struct file * filp = list_entry(p, struct file, f_list);
 928                 struct dentry * dentry = filp->f_dentry;
 929
 930                 if (dentry->d_parent != de) {
 931                         continue;
 932                 }
 933                 filp->f_op = NULL;
 934         }
 935         file_list_unlock();
 936 }
 937
 938 #define BOOL_DIR_NAME "booleans"
 939
 940 static int sel_make_bools(void)
 941 {
 942         int i, ret = 0;
 943         ssize_t len;
 944         struct dentry *dentry = NULL;
 945         struct dentry *dir = bool_dir;
 946         struct inode *inode = NULL;
 947         struct inode_security_struct *isec;
 948         char **names = NULL, *page;
 949         int num;
 950         int *values = NULL;
 951         u32 sid;
 952
 953         /* remove any existing files */
 954         if (bool_pending_values)
 955                 kfree(bool_pending_values);
 956
 957         sel_remove_bools(dir);
 958
 959         if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
 960                 return -ENOMEM;
 961
 962         ret = security_get_bools(&num, &names, &values);
 963         if (ret != 0)
 964                 goto out;
 965
 966         for (i = 0; i < num; i++) {
 967                 dentry = d_alloc_name(dir, names[i]);
 968                 if (!dentry) {
 969                         ret = -ENOMEM;
 970                         goto err;
 971                 }
 972                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
 973                 if (!inode) {
 974                         ret = -ENOMEM;
 975                         goto err;
 976                 }
 977
 978                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
 979                 if (len < 0) {
 980                         ret = -EINVAL;
 981                         goto err;
 982                 } else if (len >= PAGE_SIZE) {
 983                         ret = -ENAMETOOLONG;
 984                         goto err;
 985                 }
 986                 isec = (struct inode_security_struct*)inode->i_security;
 987                 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
 988                         goto err;
 989                 isec->sid = sid;
 990                 isec->initialized = 1;
 991                 inode->i_fop = &sel_bool_ops;
 992                 inode->i_ino = i + BOOL_INO_OFFSET;
 993                 d_add(dentry, inode);
 994         }
 995         bool_num = num;
 996         bool_pending_values = values;
 997 out:
 998         free_page((unsigned long)page);
 999         if (names) {
1000                 for (i = 0; i < num; i++) {
1001                         if (names[i])
1002                                 kfree(names[i]);
1003                 }
1004                 kfree(names);
1005         }
1006         return ret;
1007 err:
1008         d_genocide(dir);
1009         ret = -ENOMEM;
1010         goto out;
1011 }
1012
1013 #define NULL_FILE_NAME "null"
1014
1015 struct dentry *selinux_null = NULL;
1016
1017 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1018                                             size_t count, loff_t *ppos)
1019 {
1020         char tmpbuf[TMPBUFLEN];
1021         ssize_t length;
1022
1023         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1024         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1025 }
1026
1027 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1028                                              const char __user * buf,
1029                                              size_t count, loff_t *ppos)
1030
1031 {
1032         char *page;
1033         ssize_t ret;
1034         int new_value;
1035
1036         if (count < 0 || count >= PAGE_SIZE) {
1037                 ret = -ENOMEM;
1038                 goto out;
1039         }
1040
1041         if (*ppos != 0) {
1042                 /* No partial writes. */
1043                 ret = -EINVAL;
1044                 goto out;
1045         }
1046
1047         page = (char*)get_zeroed_page(GFP_KERNEL);
1048         if (!page) {
1049                 ret = -ENOMEM;
1050                 goto out;
1051         }
1052
1053         if (copy_from_user(page, buf, count)) {
1054                 ret = -EFAULT;
1055                 goto out_free;
1056         }
1057
1058         if (sscanf(page, "%u", &new_value) != 1) {
1059                 ret = -EINVAL;
1060                 goto out;
1061         }
1062
1063         if (new_value != avc_cache_threshold) {
1064                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1065                 if (ret)
1066                         goto out_free;
1067                 avc_cache_threshold = new_value;
1068         }
1069         ret = count;
1070 out_free:
1071         free_page((unsigned long)page);
1072 out:
1073         return ret;
1074 }
1075
1076 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1077                                        size_t count, loff_t *ppos)
1078 {
1079         char *page;
1080         ssize_t ret = 0;
1081
1082         page = (char *)__get_free_page(GFP_KERNEL);
1083         if (!page) {
1084                 ret = -ENOMEM;
1085                 goto out;
1086         }
1087         ret = avc_get_hash_stats(page);
1088         if (ret >= 0)
1089                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1090         free_page((unsigned long)page);
1091 out:
1092         return ret;
1093 }
1094
1095 static struct file_operations sel_avc_cache_threshold_ops = {
1096         .read           = sel_read_avc_cache_threshold,
1097         .write          = sel_write_avc_cache_threshold,
1098 };
1099
1100 static struct file_operations sel_avc_hash_stats_ops = {
1101         .read           = sel_read_avc_hash_stats,
1102 };
1103
1104 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1105 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1106 {
1107         int cpu;
1108
1109         for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1110                 if (!cpu_possible(cpu))
1111                         continue;
1112                 *idx = cpu + 1;
1113                 return &per_cpu(avc_cache_stats, cpu);
1114         }
1115         return NULL;
1116 }
1117
1118 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1119 {
1120         loff_t n = *pos - 1;
1121
1122         if (*pos == 0)
1123                 return SEQ_START_TOKEN;
1124
1125         return sel_avc_get_stat_idx(&n);
1126 }
1127
1128 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1129 {
1130         return sel_avc_get_stat_idx(pos);
1131 }
1132
1133 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1134 {
1135         struct avc_cache_stats *st = v;
1136
1137         if (v == SEQ_START_TOKEN)
1138                 seq_printf(seq, "lookups hits misses allocations reclaims "
1139                            "frees\n");
1140         else
1141                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1142                            st->hits, st->misses, st->allocations,
1143                            st->reclaims, st->frees);
1144         return 0;
1145 }
1146
1147 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1148 { }
1149
1150 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1151         .start          = sel_avc_stats_seq_start,
1152         .next           = sel_avc_stats_seq_next,
1153         .show           = sel_avc_stats_seq_show,
1154         .stop           = sel_avc_stats_seq_stop,
1155 };
1156
1157 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1158 {
1159         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1160 }
1161
1162 static struct file_operations sel_avc_cache_stats_ops = {
1163         .open           = sel_open_avc_cache_stats,
1164         .read           = seq_read,
1165         .llseek         = seq_lseek,
1166         .release        = seq_release,
1167 };
1168 #endif
1169
1170 static int sel_make_avc_files(struct dentry *dir)
1171 {
1172         int i, ret = 0;
1173         static struct tree_descr files[] = {
1174                 { "cache_threshold",
1175                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1176                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1177 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1178                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1179 #endif
1180         };
1181
1182         for (i = 0; i < sizeof (files) / sizeof (files[0]); i++) {
1183                 struct inode *inode;
1184                 struct dentry *dentry;
1185
1186                 dentry = d_alloc_name(dir, files[i].name);
1187                 if (!dentry) {
1188                         ret = -ENOMEM;
1189                         goto err;
1190                 }
1191
1192                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1193                 if (!inode) {
1194                         ret = -ENOMEM;
1195                         goto err;
1196                 }
1197                 inode->i_fop = files[i].ops;
1198                 d_add(dentry, inode);
1199         }
1200 out:
1201         return ret;
1202 err:
1203         d_genocide(dir);
1204         goto out;
1205 }
1206
1207 static int sel_make_dir(struct super_block *sb, struct dentry *dentry)
1208 {
1209         int ret = 0;
1210         struct inode *inode;
1211
1212         inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1213         if (!inode) {
1214                 ret = -ENOMEM;
1215                 goto out;
1216         }
1217         inode->i_op = &simple_dir_inode_operations;
1218         inode->i_fop = &simple_dir_operations;
1219         d_add(dentry, inode);
1220 out:
1221         return ret;
1222 }
1223
1224 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1225 {
1226         int ret;
1227         struct dentry *dentry;
1228         struct inode *inode;
1229         struct inode_security_struct *isec;
1230
1231         static struct tree_descr selinux_files[] = {
1232                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1233                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1234                 [SEL_CONTEXT] = {"context", &sel_context_ops, S_IRUGO|S_IWUGO},
1235                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1236                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1237                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1238                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1239                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1240                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1241                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1242                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1243                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1244                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1245                 /* last one */ {""}
1246         };
1247         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1248         if (ret)
1249                 return ret;
1250
1251         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1252         if (!dentry)
1253                 return -ENOMEM;
1254
1255         inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1256         if (!inode)
1257                 goto out;
1258         inode->i_op = &simple_dir_inode_operations;
1259         inode->i_fop = &simple_dir_operations;
1260         d_add(dentry, inode);
1261         bool_dir = dentry;
1262         ret = sel_make_bools();
1263         if (ret)
1264                 goto out;
1265
1266         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1267         if (!dentry)
1268                 return -ENOMEM;
1269
1270         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1271         if (!inode)
1272                 goto out;
1273         isec = (struct inode_security_struct*)inode->i_security;
1274         isec->sid = SECINITSID_DEVNULL;
1275         isec->sclass = SECCLASS_CHR_FILE;
1276         isec->initialized = 1;
1277
1278         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1279         d_add(dentry, inode);
1280         selinux_null = dentry;
1281
1282         dentry = d_alloc_name(sb->s_root, "avc");
1283         if (!dentry)
1284                 return -ENOMEM;
1285
1286         ret = sel_make_dir(sb, dentry);
1287         if (ret)
1288                 goto out;
1289
1290         ret = sel_make_avc_files(dentry);
1291         if (ret)
1292                 goto out;
1293
1294         return 0;
1295 out:
1296         dput(dentry);
1297         printk(KERN_ERR "%s:  failed while creating inodes\n", __FUNCTION__);
1298         return -ENOMEM;
1299 }
1300
1301 static struct super_block *sel_get_sb(struct file_system_type *fs_type,
1302                                       int flags, const char *dev_name, void *data)
1303 {
1304         return get_sb_single(fs_type, flags, data, sel_fill_super);
1305 }
1306
1307 static struct file_system_type sel_fs_type = {
1308         .name           = "selinuxfs",
1309         .get_sb         = sel_get_sb,
1310         .kill_sb        = kill_litter_super,
1311 };
1312
1313 struct vfsmount *selinuxfs_mount;
1314
1315 static int __init init_sel_fs(void)
1316 {
1317         int err;
1318
1319         if (!selinux_enabled)
1320                 return 0;
1321         err = register_filesystem(&sel_fs_type);
1322         if (!err) {
1323                 selinuxfs_mount = kern_mount(&sel_fs_type);
1324                 if (IS_ERR(selinuxfs_mount)) {
1325                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1326                         err = PTR_ERR(selinuxfs_mount);
1327                         selinuxfs_mount = NULL;
1328                 }
1329         }
1330         return err;
1331 }
1332
1333 __initcall(init_sel_fs);
1334
1335 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1336 void exit_sel_fs(void)
1337 {
1338         unregister_filesystem(&sel_fs_type);
1339 }
1340 #endif