git.oblomov.eu Git - linux-2.6/blob - 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 >= 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 >= 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 > 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 >= 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 >= 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 = kzalloc(size+1, GFP_KERNEL);
 428         if (!scon)
 429                 return length;
 430
 431         tcon = kzalloc(size+1, GFP_KERNEL);
 432         if (!tcon)
 433                 goto out;
 434
 435         length = -EINVAL;
 436         if (sscanf(buf, "%s %s %hu %x", scon, tcon, &tclass, &req) != 4)
 437                 goto out2;
 438
 439         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 440         if (length < 0)
 441                 goto out2;
 442         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 443         if (length < 0)
 444                 goto out2;
 445
 446         length = security_compute_av(ssid, tsid, tclass, req, &avd);
 447         if (length < 0)
 448                 goto out2;
 449
 450         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 451                           "%x %x %x %x %u",
 452                           avd.allowed, avd.decided,
 453                           avd.auditallow, avd.auditdeny,
 454                           avd.seqno);
 455 out2:
 456         kfree(tcon);
 457 out:
 458         kfree(scon);
 459         return length;
 460 }
 461
 462 static ssize_t sel_write_create(struct file * file, char *buf, size_t size)
 463 {
 464         char *scon, *tcon;
 465         u32 ssid, tsid, newsid;
 466         u16 tclass;
 467         ssize_t length;
 468         char *newcon;
 469         u32 len;
 470
 471         length = task_has_security(current, SECURITY__COMPUTE_CREATE);
 472         if (length)
 473                 return length;
 474
 475         length = -ENOMEM;
 476         scon = kzalloc(size+1, GFP_KERNEL);
 477         if (!scon)
 478                 return length;
 479
 480         tcon = kzalloc(size+1, GFP_KERNEL);
 481         if (!tcon)
 482                 goto out;
 483
 484         length = -EINVAL;
 485         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 486                 goto out2;
 487
 488         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 489         if (length < 0)
 490                 goto out2;
 491         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 492         if (length < 0)
 493                 goto out2;
 494
 495         length = security_transition_sid(ssid, tsid, tclass, &newsid);
 496         if (length < 0)
 497                 goto out2;
 498
 499         length = security_sid_to_context(newsid, &newcon, &len);
 500         if (length < 0)
 501                 goto out2;
 502
 503         if (len > SIMPLE_TRANSACTION_LIMIT) {
 504                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
 505                        "max\n", __FUNCTION__, len);
 506                 length = -ERANGE;
 507                 goto out3;
 508         }
 509
 510         memcpy(buf, newcon, len);
 511         length = len;
 512 out3:
 513         kfree(newcon);
 514 out2:
 515         kfree(tcon);
 516 out:
 517         kfree(scon);
 518         return length;
 519 }
 520
 521 static ssize_t sel_write_relabel(struct file * file, char *buf, size_t size)
 522 {
 523         char *scon, *tcon;
 524         u32 ssid, tsid, newsid;
 525         u16 tclass;
 526         ssize_t length;
 527         char *newcon;
 528         u32 len;
 529
 530         length = task_has_security(current, SECURITY__COMPUTE_RELABEL);
 531         if (length)
 532                 return length;
 533
 534         length = -ENOMEM;
 535         scon = kzalloc(size+1, GFP_KERNEL);
 536         if (!scon)
 537                 return length;
 538
 539         tcon = kzalloc(size+1, GFP_KERNEL);
 540         if (!tcon)
 541                 goto out;
 542
 543         length = -EINVAL;
 544         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 545                 goto out2;
 546
 547         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 548         if (length < 0)
 549                 goto out2;
 550         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 551         if (length < 0)
 552                 goto out2;
 553
 554         length = security_change_sid(ssid, tsid, tclass, &newsid);
 555         if (length < 0)
 556                 goto out2;
 557
 558         length = security_sid_to_context(newsid, &newcon, &len);
 559         if (length < 0)
 560                 goto out2;
 561
 562         if (len > SIMPLE_TRANSACTION_LIMIT) {
 563                 length = -ERANGE;
 564                 goto out3;
 565         }
 566
 567         memcpy(buf, newcon, len);
 568         length = len;
 569 out3:
 570         kfree(newcon);
 571 out2:
 572         kfree(tcon);
 573 out:
 574         kfree(scon);
 575         return length;
 576 }
 577
 578 static ssize_t sel_write_user(struct file * file, char *buf, size_t size)
 579 {
 580         char *con, *user, *ptr;
 581         u32 sid, *sids;
 582         ssize_t length;
 583         char *newcon;
 584         int i, rc;
 585         u32 len, nsids;
 586
 587         length = task_has_security(current, SECURITY__COMPUTE_USER);
 588         if (length)
 589                 return length;
 590
 591         length = -ENOMEM;
 592         con = kzalloc(size+1, GFP_KERNEL);
 593         if (!con)
 594                 return length;
 595
 596         user = kzalloc(size+1, GFP_KERNEL);
 597         if (!user)
 598                 goto out;
 599
 600         length = -EINVAL;
 601         if (sscanf(buf, "%s %s", con, user) != 2)
 602                 goto out2;
 603
 604         length = security_context_to_sid(con, strlen(con)+1, &sid);
 605         if (length < 0)
 606                 goto out2;
 607
 608         length = security_get_user_sids(sid, user, &sids, &nsids);
 609         if (length < 0)
 610                 goto out2;
 611
 612         length = sprintf(buf, "%u", nsids) + 1;
 613         ptr = buf + length;
 614         for (i = 0; i < nsids; i++) {
 615                 rc = security_sid_to_context(sids[i], &newcon, &len);
 616                 if (rc) {
 617                         length = rc;
 618                         goto out3;
 619                 }
 620                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
 621                         kfree(newcon);
 622                         length = -ERANGE;
 623                         goto out3;
 624                 }
 625                 memcpy(ptr, newcon, len);
 626                 kfree(newcon);
 627                 ptr += len;
 628                 length += len;
 629         }
 630 out3:
 631         kfree(sids);
 632 out2:
 633         kfree(user);
 634 out:
 635         kfree(con);
 636         return length;
 637 }
 638
 639 static ssize_t sel_write_member(struct file * file, char *buf, size_t size)
 640 {
 641         char *scon, *tcon;
 642         u32 ssid, tsid, newsid;
 643         u16 tclass;
 644         ssize_t length;
 645         char *newcon;
 646         u32 len;
 647
 648         length = task_has_security(current, SECURITY__COMPUTE_MEMBER);
 649         if (length)
 650                 return length;
 651
 652         length = -ENOMEM;
 653         scon = kzalloc(size+1, GFP_KERNEL);
 654         if (!scon)
 655                 return length;
 656
 657         tcon = kzalloc(size+1, GFP_KERNEL);
 658         if (!tcon)
 659                 goto out;
 660
 661         length = -EINVAL;
 662         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 663                 goto out2;
 664
 665         length = security_context_to_sid(scon, strlen(scon)+1, &ssid);
 666         if (length < 0)
 667                 goto out2;
 668         length = security_context_to_sid(tcon, strlen(tcon)+1, &tsid);
 669         if (length < 0)
 670                 goto out2;
 671
 672         length = security_member_sid(ssid, tsid, tclass, &newsid);
 673         if (length < 0)
 674                 goto out2;
 675
 676         length = security_sid_to_context(newsid, &newcon, &len);
 677         if (length < 0)
 678                 goto out2;
 679
 680         if (len > SIMPLE_TRANSACTION_LIMIT) {
 681                 printk(KERN_ERR "%s:  context size (%u) exceeds payload "
 682                        "max\n", __FUNCTION__, len);
 683                 length = -ERANGE;
 684                 goto out3;
 685         }
 686
 687         memcpy(buf, newcon, len);
 688         length = len;
 689 out3:
 690         kfree(newcon);
 691 out2:
 692         kfree(tcon);
 693 out:
 694         kfree(scon);
 695         return length;
 696 }
 697
 698 static struct inode *sel_make_inode(struct super_block *sb, int mode)
 699 {
 700         struct inode *ret = new_inode(sb);
 701
 702         if (ret) {
 703                 ret->i_mode = mode;
 704                 ret->i_uid = ret->i_gid = 0;
 705                 ret->i_blksize = PAGE_CACHE_SIZE;
 706                 ret->i_blocks = 0;
 707                 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
 708         }
 709         return ret;
 710 }
 711
 712 #define BOOL_INO_OFFSET 30
 713
 714 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
 715                              size_t count, loff_t *ppos)
 716 {
 717         char *page = NULL;
 718         ssize_t length;
 719         ssize_t end;
 720         ssize_t ret;
 721         int cur_enforcing;
 722         struct inode *inode;
 723
 724         down(&sel_sem);
 725
 726         ret = -EFAULT;
 727
 728         /* check to see if this file has been deleted */
 729         if (!filep->f_op)
 730                 goto out;
 731
 732         if (count > PAGE_SIZE) {
 733                 ret = -EINVAL;
 734                 goto out;
 735         }
 736         if (!(page = (char*)get_zeroed_page(GFP_KERNEL))) {
 737                 ret = -ENOMEM;
 738                 goto out;
 739         }
 740
 741         inode = filep->f_dentry->d_inode;
 742         cur_enforcing = security_get_bool_value(inode->i_ino - BOOL_INO_OFFSET);
 743         if (cur_enforcing < 0) {
 744                 ret = cur_enforcing;
 745                 goto out;
 746         }
 747
 748         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
 749                           bool_pending_values[inode->i_ino - BOOL_INO_OFFSET]);
 750         if (length < 0) {
 751                 ret = length;
 752                 goto out;
 753         }
 754
 755         if (*ppos >= length) {
 756                 ret = 0;
 757                 goto out;
 758         }
 759         if (count + *ppos > length)
 760                 count = length - *ppos;
 761         end = count + *ppos;
 762         if (copy_to_user(buf, (char *) page + *ppos, count)) {
 763                 ret = -EFAULT;
 764                 goto out;
 765         }
 766         *ppos = end;
 767         ret = count;
 768 out:
 769         up(&sel_sem);
 770         if (page)
 771                 free_page((unsigned long)page);
 772         return ret;
 773 }
 774
 775 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
 776                               size_t count, loff_t *ppos)
 777 {
 778         char *page = NULL;
 779         ssize_t length = -EFAULT;
 780         int new_value;
 781         struct inode *inode;
 782
 783         down(&sel_sem);
 784
 785         length = task_has_security(current, SECURITY__SETBOOL);
 786         if (length)
 787                 goto out;
 788
 789         /* check to see if this file has been deleted */
 790         if (!filep->f_op)
 791                 goto out;
 792
 793         if (count >= PAGE_SIZE) {
 794                 length = -ENOMEM;
 795                 goto out;
 796         }
 797         if (*ppos != 0) {
 798                 /* No partial writes. */
 799                 goto out;
 800         }
 801         page = (char*)get_zeroed_page(GFP_KERNEL);
 802         if (!page) {
 803                 length = -ENOMEM;
 804                 goto out;
 805         }
 806
 807         if (copy_from_user(page, buf, count))
 808                 goto out;
 809
 810         length = -EINVAL;
 811         if (sscanf(page, "%d", &new_value) != 1)
 812                 goto out;
 813
 814         if (new_value)
 815                 new_value = 1;
 816
 817         inode = filep->f_dentry->d_inode;
 818         bool_pending_values[inode->i_ino - BOOL_INO_OFFSET] = new_value;
 819         length = count;
 820
 821 out:
 822         up(&sel_sem);
 823         if (page)
 824                 free_page((unsigned long) page);
 825         return length;
 826 }
 827
 828 static struct file_operations sel_bool_ops = {
 829         .read           = sel_read_bool,
 830         .write          = sel_write_bool,
 831 };
 832
 833 static ssize_t sel_commit_bools_write(struct file *filep,
 834                                       const char __user *buf,
 835                                       size_t count, loff_t *ppos)
 836 {
 837         char *page = NULL;
 838         ssize_t length = -EFAULT;
 839         int new_value;
 840
 841         down(&sel_sem);
 842
 843         length = task_has_security(current, SECURITY__SETBOOL);
 844         if (length)
 845                 goto out;
 846
 847         /* check to see if this file has been deleted */
 848         if (!filep->f_op)
 849                 goto out;
 850
 851         if (count >= PAGE_SIZE) {
 852                 length = -ENOMEM;
 853                 goto out;
 854         }
 855         if (*ppos != 0) {
 856                 /* No partial writes. */
 857                 goto out;
 858         }
 859         page = (char*)get_zeroed_page(GFP_KERNEL);
 860         if (!page) {
 861                 length = -ENOMEM;
 862                 goto out;
 863         }
 864
 865         if (copy_from_user(page, buf, count))
 866                 goto out;
 867
 868         length = -EINVAL;
 869         if (sscanf(page, "%d", &new_value) != 1)
 870                 goto out;
 871
 872         if (new_value && bool_pending_values) {
 873                 security_set_bools(bool_num, bool_pending_values);
 874         }
 875
 876         length = count;
 877
 878 out:
 879         up(&sel_sem);
 880         if (page)
 881                 free_page((unsigned long) page);
 882         return length;
 883 }
 884
 885 static struct file_operations sel_commit_bools_ops = {
 886         .write          = sel_commit_bools_write,
 887 };
 888
 889 /* delete booleans - partial revoke() from
 890  * fs/proc/generic.c proc_kill_inodes */
 891 static void sel_remove_bools(struct dentry *de)
 892 {
 893         struct list_head *p, *node;
 894         struct super_block *sb = de->d_sb;
 895
 896         spin_lock(&dcache_lock);
 897         node = de->d_subdirs.next;
 898         while (node != &de->d_subdirs) {
 899                 struct dentry *d = list_entry(node, struct dentry, d_child);
 900                 list_del_init(node);
 901
 902                 if (d->d_inode) {
 903                         d = dget_locked(d);
 904                         spin_unlock(&dcache_lock);
 905                         d_delete(d);
 906                         simple_unlink(de->d_inode, d);
 907                         dput(d);
 908                         spin_lock(&dcache_lock);
 909                 }
 910                 node = de->d_subdirs.next;
 911         }
 912
 913         spin_unlock(&dcache_lock);
 914
 915         file_list_lock();
 916         list_for_each(p, &sb->s_files) {
 917                 struct file * filp = list_entry(p, struct file, f_list);
 918                 struct dentry * dentry = filp->f_dentry;
 919
 920                 if (dentry->d_parent != de) {
 921                         continue;
 922                 }
 923                 filp->f_op = NULL;
 924         }
 925         file_list_unlock();
 926 }
 927
 928 #define BOOL_DIR_NAME "booleans"
 929
 930 static int sel_make_bools(void)
 931 {
 932         int i, ret = 0;
 933         ssize_t len;
 934         struct dentry *dentry = NULL;
 935         struct dentry *dir = bool_dir;
 936         struct inode *inode = NULL;
 937         struct inode_security_struct *isec;
 938         char **names = NULL, *page;
 939         int num;
 940         int *values = NULL;
 941         u32 sid;
 942
 943         /* remove any existing files */
 944         kfree(bool_pending_values);
 945         bool_pending_values = NULL;
 946
 947         sel_remove_bools(dir);
 948
 949         if (!(page = (char*)get_zeroed_page(GFP_KERNEL)))
 950                 return -ENOMEM;
 951
 952         ret = security_get_bools(&num, &names, &values);
 953         if (ret != 0)
 954                 goto out;
 955
 956         for (i = 0; i < num; i++) {
 957                 dentry = d_alloc_name(dir, names[i]);
 958                 if (!dentry) {
 959                         ret = -ENOMEM;
 960                         goto err;
 961                 }
 962                 inode = sel_make_inode(dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
 963                 if (!inode) {
 964                         ret = -ENOMEM;
 965                         goto err;
 966                 }
 967
 968                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
 969                 if (len < 0) {
 970                         ret = -EINVAL;
 971                         goto err;
 972                 } else if (len >= PAGE_SIZE) {
 973                         ret = -ENAMETOOLONG;
 974                         goto err;
 975                 }
 976                 isec = (struct inode_security_struct*)inode->i_security;
 977                 if ((ret = security_genfs_sid("selinuxfs", page, SECCLASS_FILE, &sid)))
 978                         goto err;
 979                 isec->sid = sid;
 980                 isec->initialized = 1;
 981                 inode->i_fop = &sel_bool_ops;
 982                 inode->i_ino = i + BOOL_INO_OFFSET;
 983                 d_add(dentry, inode);
 984         }
 985         bool_num = num;
 986         bool_pending_values = values;
 987 out:
 988         free_page((unsigned long)page);
 989         if (names) {
 990                 for (i = 0; i < num; i++)
 991                         kfree(names[i]);
 992                 kfree(names);
 993         }
 994         return ret;
 995 err:
 996         kfree(values);
 997         d_genocide(dir);
 998         ret = -ENOMEM;
 999         goto out;
1000 }
1001
1002 #define NULL_FILE_NAME "null"
1003
1004 struct dentry *selinux_null = NULL;
1005
1006 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1007                                             size_t count, loff_t *ppos)
1008 {
1009         char tmpbuf[TMPBUFLEN];
1010         ssize_t length;
1011
1012         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", avc_cache_threshold);
1013         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1014 }
1015
1016 static ssize_t sel_write_avc_cache_threshold(struct file * file,
1017                                              const char __user * buf,
1018                                              size_t count, loff_t *ppos)
1019
1020 {
1021         char *page;
1022         ssize_t ret;
1023         int new_value;
1024
1025         if (count >= PAGE_SIZE) {
1026                 ret = -ENOMEM;
1027                 goto out;
1028         }
1029
1030         if (*ppos != 0) {
1031                 /* No partial writes. */
1032                 ret = -EINVAL;
1033                 goto out;
1034         }
1035
1036         page = (char*)get_zeroed_page(GFP_KERNEL);
1037         if (!page) {
1038                 ret = -ENOMEM;
1039                 goto out;
1040         }
1041
1042         if (copy_from_user(page, buf, count)) {
1043                 ret = -EFAULT;
1044                 goto out_free;
1045         }
1046
1047         if (sscanf(page, "%u", &new_value) != 1) {
1048                 ret = -EINVAL;
1049                 goto out;
1050         }
1051
1052         if (new_value != avc_cache_threshold) {
1053                 ret = task_has_security(current, SECURITY__SETSECPARAM);
1054                 if (ret)
1055                         goto out_free;
1056                 avc_cache_threshold = new_value;
1057         }
1058         ret = count;
1059 out_free:
1060         free_page((unsigned long)page);
1061 out:
1062         return ret;
1063 }
1064
1065 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1066                                        size_t count, loff_t *ppos)
1067 {
1068         char *page;
1069         ssize_t ret = 0;
1070
1071         page = (char *)__get_free_page(GFP_KERNEL);
1072         if (!page) {
1073                 ret = -ENOMEM;
1074                 goto out;
1075         }
1076         ret = avc_get_hash_stats(page);
1077         if (ret >= 0)
1078                 ret = simple_read_from_buffer(buf, count, ppos, page, ret);
1079         free_page((unsigned long)page);
1080 out:
1081         return ret;
1082 }
1083
1084 static struct file_operations sel_avc_cache_threshold_ops = {
1085         .read           = sel_read_avc_cache_threshold,
1086         .write          = sel_write_avc_cache_threshold,
1087 };
1088
1089 static struct file_operations sel_avc_hash_stats_ops = {
1090         .read           = sel_read_avc_hash_stats,
1091 };
1092
1093 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1094 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1095 {
1096         int cpu;
1097
1098         for (cpu = *idx; cpu < NR_CPUS; ++cpu) {
1099                 if (!cpu_possible(cpu))
1100                         continue;
1101                 *idx = cpu + 1;
1102                 return &per_cpu(avc_cache_stats, cpu);
1103         }
1104         return NULL;
1105 }
1106
1107 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1108 {
1109         loff_t n = *pos - 1;
1110
1111         if (*pos == 0)
1112                 return SEQ_START_TOKEN;
1113
1114         return sel_avc_get_stat_idx(&n);
1115 }
1116
1117 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1118 {
1119         return sel_avc_get_stat_idx(pos);
1120 }
1121
1122 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1123 {
1124         struct avc_cache_stats *st = v;
1125
1126         if (v == SEQ_START_TOKEN)
1127                 seq_printf(seq, "lookups hits misses allocations reclaims "
1128                            "frees\n");
1129         else
1130                 seq_printf(seq, "%u %u %u %u %u %u\n", st->lookups,
1131                            st->hits, st->misses, st->allocations,
1132                            st->reclaims, st->frees);
1133         return 0;
1134 }
1135
1136 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1137 { }
1138
1139 static struct seq_operations sel_avc_cache_stats_seq_ops = {
1140         .start          = sel_avc_stats_seq_start,
1141         .next           = sel_avc_stats_seq_next,
1142         .show           = sel_avc_stats_seq_show,
1143         .stop           = sel_avc_stats_seq_stop,
1144 };
1145
1146 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1147 {
1148         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1149 }
1150
1151 static struct file_operations sel_avc_cache_stats_ops = {
1152         .open           = sel_open_avc_cache_stats,
1153         .read           = seq_read,
1154         .llseek         = seq_lseek,
1155         .release        = seq_release,
1156 };
1157 #endif
1158
1159 static int sel_make_avc_files(struct dentry *dir)
1160 {
1161         int i, ret = 0;
1162         static struct tree_descr files[] = {
1163                 { "cache_threshold",
1164                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1165                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1166 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1167                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1168 #endif
1169         };
1170
1171         for (i = 0; i < sizeof (files) / sizeof (files[0]); i++) {
1172                 struct inode *inode;
1173                 struct dentry *dentry;
1174
1175                 dentry = d_alloc_name(dir, files[i].name);
1176                 if (!dentry) {
1177                         ret = -ENOMEM;
1178                         goto err;
1179                 }
1180
1181                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1182                 if (!inode) {
1183                         ret = -ENOMEM;
1184                         goto err;
1185                 }
1186                 inode->i_fop = files[i].ops;
1187                 d_add(dentry, inode);
1188         }
1189 out:
1190         return ret;
1191 err:
1192         d_genocide(dir);
1193         goto out;
1194 }
1195
1196 static int sel_make_dir(struct super_block *sb, struct dentry *dentry)
1197 {
1198         int ret = 0;
1199         struct inode *inode;
1200
1201         inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1202         if (!inode) {
1203                 ret = -ENOMEM;
1204                 goto out;
1205         }
1206         inode->i_op = &simple_dir_inode_operations;
1207         inode->i_fop = &simple_dir_operations;
1208         d_add(dentry, inode);
1209 out:
1210         return ret;
1211 }
1212
1213 static int sel_fill_super(struct super_block * sb, void * data, int silent)
1214 {
1215         int ret;
1216         struct dentry *dentry;
1217         struct inode *inode;
1218         struct inode_security_struct *isec;
1219
1220         static struct tree_descr selinux_files[] = {
1221                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1222                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1223                 [SEL_CONTEXT] = {"context", &sel_context_ops, S_IRUGO|S_IWUGO},
1224                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1225                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1226                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1227                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1228                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1229                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1230                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1231                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1232                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1233                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1234                 /* last one */ {""}
1235         };
1236         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
1237         if (ret)
1238                 return ret;
1239
1240         dentry = d_alloc_name(sb->s_root, BOOL_DIR_NAME);
1241         if (!dentry)
1242                 return -ENOMEM;
1243
1244         inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1245         if (!inode)
1246                 goto out;
1247         inode->i_op = &simple_dir_inode_operations;
1248         inode->i_fop = &simple_dir_operations;
1249         d_add(dentry, inode);
1250         bool_dir = dentry;
1251         ret = sel_make_bools();
1252         if (ret)
1253                 goto out;
1254
1255         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
1256         if (!dentry)
1257                 return -ENOMEM;
1258
1259         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
1260         if (!inode)
1261                 goto out;
1262         isec = (struct inode_security_struct*)inode->i_security;
1263         isec->sid = SECINITSID_DEVNULL;
1264         isec->sclass = SECCLASS_CHR_FILE;
1265         isec->initialized = 1;
1266
1267         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
1268         d_add(dentry, inode);
1269         selinux_null = dentry;
1270
1271         dentry = d_alloc_name(sb->s_root, "avc");
1272         if (!dentry)
1273                 return -ENOMEM;
1274
1275         ret = sel_make_dir(sb, dentry);
1276         if (ret)
1277                 goto out;
1278
1279         ret = sel_make_avc_files(dentry);
1280         if (ret)
1281                 goto out;
1282
1283         return 0;
1284 out:
1285         dput(dentry);
1286         printk(KERN_ERR "%s:  failed while creating inodes\n", __FUNCTION__);
1287         return -ENOMEM;
1288 }
1289
1290 static struct super_block *sel_get_sb(struct file_system_type *fs_type,
1291                                       int flags, const char *dev_name, void *data)
1292 {
1293         return get_sb_single(fs_type, flags, data, sel_fill_super);
1294 }
1295
1296 static struct file_system_type sel_fs_type = {
1297         .name           = "selinuxfs",
1298         .get_sb         = sel_get_sb,
1299         .kill_sb        = kill_litter_super,
1300 };
1301
1302 struct vfsmount *selinuxfs_mount;
1303
1304 static int __init init_sel_fs(void)
1305 {
1306         int err;
1307
1308         if (!selinux_enabled)
1309                 return 0;
1310         err = register_filesystem(&sel_fs_type);
1311         if (!err) {
1312                 selinuxfs_mount = kern_mount(&sel_fs_type);
1313                 if (IS_ERR(selinuxfs_mount)) {
1314                         printk(KERN_ERR "selinuxfs:  could not mount!\n");
1315                         err = PTR_ERR(selinuxfs_mount);
1316                         selinuxfs_mount = NULL;
1317                 }
1318         }
1319         return err;
1320 }
1321
1322 __initcall(init_sel_fs);
1323
1324 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
1325 void exit_sel_fs(void)
1326 {
1327         unregister_filesystem(&sel_fs_type);
1328 }
1329 #endif