security/tomoyo/common.c

   1 /*
   2  * security/tomoyo/common.c
   3  *
   4  * Common functions for TOMOYO.
   5  *
   6  * Copyright (C) 2005-2010  NTT DATA CORPORATION
   7  */
   8
   9 #include <linux/uaccess.h>
  10 #include <linux/slab.h>
  11 #include <linux/security.h>
  12 #include <linux/hardirq.h>
  13 #include "common.h"
  14
  15 /* String table for functionality that takes 4 modes. */
  16 static const char *tomoyo_mode_4[4] = {
  17         "disabled", "learning", "permissive", "enforcing"
  18 };
  19 /* String table for functionality that takes 2 modes. */
  20 static const char *tomoyo_mode_2[4] = {
  21         "disabled", "enabled", "enabled", "enabled"
  22 };
  23
  24 /*
  25  * tomoyo_control_array is a static data which contains
  26  *
  27  *  (1) functionality name used by /sys/kernel/security/tomoyo/profile .
  28  *  (2) initial values for "struct tomoyo_profile".
  29  *  (3) max values for "struct tomoyo_profile".
  30  */
  31 static struct {
  32         const char *keyword;
  33         unsigned int current_value;
  34         const unsigned int max_value;
  35 } tomoyo_control_array[TOMOYO_MAX_CONTROL_INDEX] = {
  36         [TOMOYO_MAC_FOR_FILE]     = { "MAC_FOR_FILE",        0,       3 },
  37         [TOMOYO_MAX_ACCEPT_ENTRY] = { "MAX_ACCEPT_ENTRY", 2048, INT_MAX },
  38         [TOMOYO_VERBOSE]          = { "TOMOYO_VERBOSE",      1,       1 },
  39 };
  40
  41 /*
  42  * tomoyo_profile is a structure which is used for holding the mode of access
  43  * controls. TOMOYO has 4 modes: disabled, learning, permissive, enforcing.
  44  * An administrator can define up to 256 profiles.
  45  * The ->profile of "struct tomoyo_domain_info" is used for remembering
  46  * the profile's number (0 - 255) assigned to that domain.
  47  */
  48 static struct tomoyo_profile {
  49         unsigned int value[TOMOYO_MAX_CONTROL_INDEX];
  50         const struct tomoyo_path_info *comment;
  51 } *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
  52
  53 /* Permit policy management by non-root user? */
  54 static bool tomoyo_manage_by_non_root;
  55
  56 /* Utility functions. */
  57
  58 /**
  59  * tomoyo_print_name_union - Print a tomoyo_name_union.
  60  *
  61  * @head: Pointer to "struct tomoyo_io_buffer".
  62  * @ptr:  Pointer to "struct tomoyo_name_union".
  63  *
  64  * Returns true on success, false otherwise.
  65  */
  66 static bool tomoyo_print_name_union(struct tomoyo_io_buffer *head,
  67                                  const struct tomoyo_name_union *ptr)
  68 {
  69         int pos = head->read_avail;
  70         if (pos && head->read_buf[pos - 1] == ' ')
  71                 head->read_avail--;
  72         if (ptr->is_group)
  73                 return tomoyo_io_printf(head, " @%s",
  74                                         ptr->group->group_name->name);
  75         return tomoyo_io_printf(head, " %s", ptr->filename->name);
  76 }
  77
  78 /**
  79  * tomoyo_print_number_union - Print a tomoyo_number_union.
  80  *
  81  * @head:       Pointer to "struct tomoyo_io_buffer".
  82  * @ptr:        Pointer to "struct tomoyo_number_union".
  83  *
  84  * Returns true on success, false otherwise.
  85  */
  86 bool tomoyo_print_number_union(struct tomoyo_io_buffer *head,
  87                                const struct tomoyo_number_union *ptr)
  88 {
  89         unsigned long min;
  90         unsigned long max;
  91         u8 min_type;
  92         u8 max_type;
  93         if (!tomoyo_io_printf(head, " "))
  94                 return false;
  95         if (ptr->is_group)
  96                 return tomoyo_io_printf(head, "@%s",
  97                                         ptr->group->group_name->name);
  98         min_type = ptr->min_type;
  99         max_type = ptr->max_type;
 100         min = ptr->values[0];
 101         max = ptr->values[1];
 102         switch (min_type) {
 103         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 104                 if (!tomoyo_io_printf(head, "0x%lX", min))
 105                         return false;
 106                 break;
 107         case TOMOYO_VALUE_TYPE_OCTAL:
 108                 if (!tomoyo_io_printf(head, "0%lo", min))
 109                         return false;
 110                 break;
 111         default:
 112                 if (!tomoyo_io_printf(head, "%lu", min))
 113                         return false;
 114                 break;
 115         }
 116         if (min == max && min_type == max_type)
 117                 return true;
 118         switch (max_type) {
 119         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 120                 return tomoyo_io_printf(head, "-0x%lX", max);
 121         case TOMOYO_VALUE_TYPE_OCTAL:
 122                 return tomoyo_io_printf(head, "-0%lo", max);
 123         default:
 124                 return tomoyo_io_printf(head, "-%lu", max);
 125         }
 126 }
 127
 128 /**
 129  * tomoyo_io_printf - Transactional printf() to "struct tomoyo_io_buffer" structure.
 130  *
 131  * @head: Pointer to "struct tomoyo_io_buffer".
 132  * @fmt:  The printf()'s format string, followed by parameters.
 133  *
 134  * Returns true if output was written, false otherwise.
 135  *
 136  * The snprintf() will truncate, but tomoyo_io_printf() won't.
 137  */
 138 bool tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
 139 {
 140         va_list args;
 141         int len;
 142         int pos = head->read_avail;
 143         int size = head->readbuf_size - pos;
 144
 145         if (size <= 0)
 146                 return false;
 147         va_start(args, fmt);
 148         len = vsnprintf(head->read_buf + pos, size, fmt, args);
 149         va_end(args);
 150         if (pos + len >= head->readbuf_size)
 151                 return false;
 152         head->read_avail += len;
 153         return true;
 154 }
 155
 156 /**
 157  * tomoyo_check_flags - Check mode for specified functionality.
 158  *
 159  * @domain: Pointer to "struct tomoyo_domain_info".
 160  * @index:  The functionality to check mode.
 161  *
 162  * TOMOYO checks only process context.
 163  * This code disables TOMOYO's enforcement in case the function is called from
 164  * interrupt context.
 165  */
 166 unsigned int tomoyo_check_flags(const struct tomoyo_domain_info *domain,
 167                                 const u8 index)
 168 {
 169         const u8 profile = domain->profile;
 170
 171         if (WARN_ON(in_interrupt()))
 172                 return 0;
 173         return tomoyo_policy_loaded && index < TOMOYO_MAX_CONTROL_INDEX
 174 #if TOMOYO_MAX_PROFILES != 256
 175                 && profile < TOMOYO_MAX_PROFILES
 176 #endif
 177                 && tomoyo_profile_ptr[profile] ?
 178                 tomoyo_profile_ptr[profile]->value[index] : 0;
 179 }
 180
 181 /**
 182  * tomoyo_verbose_mode - Check whether TOMOYO is verbose mode.
 183  *
 184  * @domain: Pointer to "struct tomoyo_domain_info".
 185  *
 186  * Returns true if domain policy violation warning should be printed to
 187  * console.
 188  */
 189 bool tomoyo_verbose_mode(const struct tomoyo_domain_info *domain)
 190 {
 191         return tomoyo_check_flags(domain, TOMOYO_VERBOSE) != 0;
 192 }
 193
 194 /**
 195  * tomoyo_find_or_assign_new_profile - Create a new profile.
 196  *
 197  * @profile: Profile number to create.
 198  *
 199  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
 200  */
 201 static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned
 202                                                                 int profile)
 203 {
 204         struct tomoyo_profile *ptr = NULL;
 205         int i;
 206
 207         if (profile >= TOMOYO_MAX_PROFILES)
 208                 return NULL;
 209         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 210                 return NULL;
 211         ptr = tomoyo_profile_ptr[profile];
 212         if (ptr)
 213                 goto ok;
 214         ptr = kmalloc(sizeof(*ptr), GFP_NOFS);
 215         if (!tomoyo_memory_ok(ptr)) {
 216                 kfree(ptr);
 217                 ptr = NULL;
 218                 goto ok;
 219         }
 220         for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++)
 221                 ptr->value[i] = tomoyo_control_array[i].current_value;
 222         mb(); /* Avoid out-of-order execution. */
 223         tomoyo_profile_ptr[profile] = ptr;
 224  ok:
 225         mutex_unlock(&tomoyo_policy_lock);
 226         return ptr;
 227 }
 228
 229 /**
 230  * tomoyo_write_profile - Write to profile table.
 231  *
 232  * @head: Pointer to "struct tomoyo_io_buffer".
 233  *
 234  * Returns 0 on success, negative value otherwise.
 235  */
 236 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
 237 {
 238         char *data = head->write_buf;
 239         unsigned int i;
 240         unsigned int value;
 241         char *cp;
 242         struct tomoyo_profile *profile;
 243         unsigned long num;
 244
 245         cp = strchr(data, '-');
 246         if (cp)
 247                 *cp = '\0';
 248         if (strict_strtoul(data, 10, &num))
 249                 return -EINVAL;
 250         if (cp)
 251                 data = cp + 1;
 252         profile = tomoyo_find_or_assign_new_profile(num);
 253         if (!profile)
 254                 return -EINVAL;
 255         cp = strchr(data, '=');
 256         if (!cp)
 257                 return -EINVAL;
 258         *cp = '\0';
 259         if (!strcmp(data, "COMMENT")) {
 260                 const struct tomoyo_path_info *old_comment = profile->comment;
 261                 profile->comment = tomoyo_get_name(cp + 1);
 262                 tomoyo_put_name(old_comment);
 263                 return 0;
 264         }
 265         for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++) {
 266                 if (strcmp(data, tomoyo_control_array[i].keyword))
 267                         continue;
 268                 if (sscanf(cp + 1, "%u", &value) != 1) {
 269                         int j;
 270                         const char **modes;
 271                         switch (i) {
 272                         case TOMOYO_VERBOSE:
 273                                 modes = tomoyo_mode_2;
 274                                 break;
 275                         default:
 276                                 modes = tomoyo_mode_4;
 277                                 break;
 278                         }
 279                         for (j = 0; j < 4; j++) {
 280                                 if (strcmp(cp + 1, modes[j]))
 281                                         continue;
 282                                 value = j;
 283                                 break;
 284                         }
 285                         if (j == 4)
 286                                 return -EINVAL;
 287                 } else if (value > tomoyo_control_array[i].max_value) {
 288                         value = tomoyo_control_array[i].max_value;
 289                 }
 290                 profile->value[i] = value;
 291                 return 0;
 292         }
 293         return -EINVAL;
 294 }
 295
 296 /**
 297  * tomoyo_read_profile - Read from profile table.
 298  *
 299  * @head: Pointer to "struct tomoyo_io_buffer".
 300  *
 301  * Returns 0.
 302  */
 303 static int tomoyo_read_profile(struct tomoyo_io_buffer *head)
 304 {
 305         static const int total = TOMOYO_MAX_CONTROL_INDEX + 1;
 306         int step;
 307
 308         if (head->read_eof)
 309                 return 0;
 310         for (step = head->read_step; step < TOMOYO_MAX_PROFILES * total;
 311              step++) {
 312                 const u8 index = step / total;
 313                 u8 type = step % total;
 314                 const struct tomoyo_profile *profile
 315                         = tomoyo_profile_ptr[index];
 316                 head->read_step = step;
 317                 if (!profile)
 318                         continue;
 319                 if (!type) { /* Print profile' comment tag. */
 320                         if (!tomoyo_io_printf(head, "%u-COMMENT=%s\n",
 321                                               index, profile->comment ?
 322                                               profile->comment->name : ""))
 323                                 break;
 324                         continue;
 325                 }
 326                 type--;
 327                 if (type < TOMOYO_MAX_CONTROL_INDEX) {
 328                         const unsigned int value = profile->value[type];
 329                         const char **modes = NULL;
 330                         const char *keyword
 331                                 = tomoyo_control_array[type].keyword;
 332                         switch (tomoyo_control_array[type].max_value) {
 333                         case 3:
 334                                 modes = tomoyo_mode_4;
 335                                 break;
 336                         case 1:
 337                                 modes = tomoyo_mode_2;
 338                                 break;
 339                         }
 340                         if (modes) {
 341                                 if (!tomoyo_io_printf(head, "%u-%s=%s\n", index,
 342                                                       keyword, modes[value]))
 343                                         break;
 344                         } else {
 345                                 if (!tomoyo_io_printf(head, "%u-%s=%u\n", index,
 346                                                       keyword, value))
 347                                         break;
 348                         }
 349                 }
 350         }
 351         if (step == TOMOYO_MAX_PROFILES * total)
 352                 head->read_eof = true;
 353         return 0;
 354 }
 355
 356 /*
 357  * tomoyo_policy_manager_list is used for holding list of domainnames or
 358  * programs which are permitted to modify configuration via
 359  * /sys/kernel/security/tomoyo/ interface.
 360  *
 361  * An entry is added by
 362  *
 363  * # echo '<kernel> /sbin/mingetty /bin/login /bin/bash' > \
 364  *                                        /sys/kernel/security/tomoyo/manager
 365  *  (if you want to specify by a domainname)
 366  *
 367  *  or
 368  *
 369  * # echo '/usr/lib/ccs/editpolicy' > /sys/kernel/security/tomoyo/manager
 370  *  (if you want to specify by a program's location)
 371  *
 372  * and is deleted by
 373  *
 374  * # echo 'delete <kernel> /sbin/mingetty /bin/login /bin/bash' > \
 375  *                                        /sys/kernel/security/tomoyo/manager
 376  *
 377  *  or
 378  *
 379  * # echo 'delete /usr/lib/ccs/editpolicy' > \
 380  *                                        /sys/kernel/security/tomoyo/manager
 381  *
 382  * and all entries are retrieved by
 383  *
 384  * # cat /sys/kernel/security/tomoyo/manager
 385  */
 386 LIST_HEAD(tomoyo_policy_manager_list);
 387
 388 /**
 389  * tomoyo_update_manager_entry - Add a manager entry.
 390  *
 391  * @manager:   The path to manager or the domainnamme.
 392  * @is_delete: True if it is a delete request.
 393  *
 394  * Returns 0 on success, negative value otherwise.
 395  *
 396  * Caller holds tomoyo_read_lock().
 397  */
 398 static int tomoyo_update_manager_entry(const char *manager,
 399                                        const bool is_delete)
 400 {
 401         struct tomoyo_policy_manager_entry *ptr;
 402         struct tomoyo_policy_manager_entry e = { };
 403         int error = is_delete ? -ENOENT : -ENOMEM;
 404
 405         if (tomoyo_is_domain_def(manager)) {
 406                 if (!tomoyo_is_correct_domain(manager))
 407                         return -EINVAL;
 408                 e.is_domain = true;
 409         } else {
 410                 if (!tomoyo_is_correct_path(manager, 1, -1, -1))
 411                         return -EINVAL;
 412         }
 413         e.manager = tomoyo_get_name(manager);
 414         if (!e.manager)
 415                 return -ENOMEM;
 416         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 417                 goto out;
 418         list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
 419                 if (ptr->manager != e.manager)
 420                         continue;
 421                 ptr->is_deleted = is_delete;
 422                 error = 0;
 423                 break;
 424         }
 425         if (!is_delete && error) {
 426                 struct tomoyo_policy_manager_entry *entry =
 427                         tomoyo_commit_ok(&e, sizeof(e));
 428                 if (entry) {
 429                         list_add_tail_rcu(&entry->list,
 430                                           &tomoyo_policy_manager_list);
 431                         error = 0;
 432                 }
 433         }
 434         mutex_unlock(&tomoyo_policy_lock);
 435  out:
 436         tomoyo_put_name(e.manager);
 437         return error;
 438 }
 439
 440 /**
 441  * tomoyo_write_manager_policy - Write manager policy.
 442  *
 443  * @head: Pointer to "struct tomoyo_io_buffer".
 444  *
 445  * Returns 0 on success, negative value otherwise.
 446  *
 447  * Caller holds tomoyo_read_lock().
 448  */
 449 static int tomoyo_write_manager_policy(struct tomoyo_io_buffer *head)
 450 {
 451         char *data = head->write_buf;
 452         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
 453
 454         if (!strcmp(data, "manage_by_non_root")) {
 455                 tomoyo_manage_by_non_root = !is_delete;
 456                 return 0;
 457         }
 458         return tomoyo_update_manager_entry(data, is_delete);
 459 }
 460
 461 /**
 462  * tomoyo_read_manager_policy - Read manager policy.
 463  *
 464  * @head: Pointer to "struct tomoyo_io_buffer".
 465  *
 466  * Returns 0.
 467  *
 468  * Caller holds tomoyo_read_lock().
 469  */
 470 static int tomoyo_read_manager_policy(struct tomoyo_io_buffer *head)
 471 {
 472         struct list_head *pos;
 473         bool done = true;
 474
 475         if (head->read_eof)
 476                 return 0;
 477         list_for_each_cookie(pos, head->read_var2,
 478                              &tomoyo_policy_manager_list) {
 479                 struct tomoyo_policy_manager_entry *ptr;
 480                 ptr = list_entry(pos, struct tomoyo_policy_manager_entry,
 481                                  list);
 482                 if (ptr->is_deleted)
 483                         continue;
 484                 done = tomoyo_io_printf(head, "%s\n", ptr->manager->name);
 485                 if (!done)
 486                         break;
 487         }
 488         head->read_eof = done;
 489         return 0;
 490 }
 491
 492 /**
 493  * tomoyo_is_policy_manager - Check whether the current process is a policy manager.
 494  *
 495  * Returns true if the current process is permitted to modify policy
 496  * via /sys/kernel/security/tomoyo/ interface.
 497  *
 498  * Caller holds tomoyo_read_lock().
 499  */
 500 static bool tomoyo_is_policy_manager(void)
 501 {
 502         struct tomoyo_policy_manager_entry *ptr;
 503         const char *exe;
 504         const struct task_struct *task = current;
 505         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
 506         bool found = false;
 507
 508         if (!tomoyo_policy_loaded)
 509                 return true;
 510         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
 511                 return false;
 512         list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
 513                 if (!ptr->is_deleted && ptr->is_domain
 514                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
 515                         found = true;
 516                         break;
 517                 }
 518         }
 519         if (found)
 520                 return true;
 521         exe = tomoyo_get_exe();
 522         if (!exe)
 523                 return false;
 524         list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
 525                 if (!ptr->is_deleted && !ptr->is_domain
 526                     && !strcmp(exe, ptr->manager->name)) {
 527                         found = true;
 528                         break;
 529                 }
 530         }
 531         if (!found) { /* Reduce error messages. */
 532                 static pid_t last_pid;
 533                 const pid_t pid = current->pid;
 534                 if (last_pid != pid) {
 535                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
 536                                "update policies.\n", domainname->name, exe);
 537                         last_pid = pid;
 538                 }
 539         }
 540         kfree(exe);
 541         return found;
 542 }
 543
 544 /**
 545  * tomoyo_is_select_one - Parse select command.
 546  *
 547  * @head: Pointer to "struct tomoyo_io_buffer".
 548  * @data: String to parse.
 549  *
 550  * Returns true on success, false otherwise.
 551  *
 552  * Caller holds tomoyo_read_lock().
 553  */
 554 static bool tomoyo_is_select_one(struct tomoyo_io_buffer *head,
 555                                  const char *data)
 556 {
 557         unsigned int pid;
 558         struct tomoyo_domain_info *domain = NULL;
 559
 560         if (sscanf(data, "pid=%u", &pid) == 1) {
 561                 struct task_struct *p;
 562                 rcu_read_lock();
 563                 read_lock(&tasklist_lock);
 564                 p = find_task_by_vpid(pid);
 565                 if (p)
 566                         domain = tomoyo_real_domain(p);
 567                 read_unlock(&tasklist_lock);
 568                 rcu_read_unlock();
 569         } else if (!strncmp(data, "domain=", 7)) {
 570                 if (tomoyo_is_domain_def(data + 7))
 571                         domain = tomoyo_find_domain(data + 7);
 572         } else
 573                 return false;
 574         head->write_var1 = domain;
 575         /* Accessing read_buf is safe because head->io_sem is held. */
 576         if (!head->read_buf)
 577                 return true; /* Do nothing if open(O_WRONLY). */
 578         head->read_avail = 0;
 579         tomoyo_io_printf(head, "# select %s\n", data);
 580         head->read_single_domain = true;
 581         head->read_eof = !domain;
 582         if (domain) {
 583                 struct tomoyo_domain_info *d;
 584                 head->read_var1 = NULL;
 585                 list_for_each_entry_rcu(d, &tomoyo_domain_list, list) {
 586                         if (d == domain)
 587                                 break;
 588                         head->read_var1 = &d->list;
 589                 }
 590                 head->read_var2 = NULL;
 591                 head->read_bit = 0;
 592                 head->read_step = 0;
 593                 if (domain->is_deleted)
 594                         tomoyo_io_printf(head, "# This is a deleted domain.\n");
 595         }
 596         return true;
 597 }
 598
 599 /**
 600  * tomoyo_delete_domain - Delete a domain.
 601  *
 602  * @domainname: The name of domain.
 603  *
 604  * Returns 0.
 605  *
 606  * Caller holds tomoyo_read_lock().
 607  */
 608 static int tomoyo_delete_domain(char *domainname)
 609 {
 610         struct tomoyo_domain_info *domain;
 611         struct tomoyo_path_info name;
 612
 613         name.name = domainname;
 614         tomoyo_fill_path_info(&name);
 615         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 616                 return 0;
 617         /* Is there an active domain? */
 618         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 619                 /* Never delete tomoyo_kernel_domain */
 620                 if (domain == &tomoyo_kernel_domain)
 621                         continue;
 622                 if (domain->is_deleted ||
 623                     tomoyo_pathcmp(domain->domainname, &name))
 624                         continue;
 625                 domain->is_deleted = true;
 626                 break;
 627         }
 628         mutex_unlock(&tomoyo_policy_lock);
 629         return 0;
 630 }
 631
 632 /**
 633  * tomoyo_write_domain_policy2 - Write domain policy.
 634  *
 635  * @head: Pointer to "struct tomoyo_io_buffer".
 636  *
 637  * Returns 0 on success, negative value otherwise.
 638  *
 639  * Caller holds tomoyo_read_lock().
 640  */
 641 static int tomoyo_write_domain_policy2(char *data,
 642                                        struct tomoyo_domain_info *domain,
 643                                        const bool is_delete)
 644 {
 645         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
 646                 return tomoyo_write_mount_policy(data, domain, is_delete);
 647         return tomoyo_write_file_policy(data, domain, is_delete);
 648 }
 649
 650 /**
 651  * tomoyo_write_domain_policy - Write domain policy.
 652  *
 653  * @head: Pointer to "struct tomoyo_io_buffer".
 654  *
 655  * Returns 0 on success, negative value otherwise.
 656  *
 657  * Caller holds tomoyo_read_lock().
 658  */
 659 static int tomoyo_write_domain_policy(struct tomoyo_io_buffer *head)
 660 {
 661         char *data = head->write_buf;
 662         struct tomoyo_domain_info *domain = head->write_var1;
 663         bool is_delete = false;
 664         bool is_select = false;
 665         unsigned int profile;
 666
 667         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE))
 668                 is_delete = true;
 669         else if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_SELECT))
 670                 is_select = true;
 671         if (is_select && tomoyo_is_select_one(head, data))
 672                 return 0;
 673         /* Don't allow updating policies by non manager programs. */
 674         if (!tomoyo_is_policy_manager())
 675                 return -EPERM;
 676         if (tomoyo_is_domain_def(data)) {
 677                 domain = NULL;
 678                 if (is_delete)
 679                         tomoyo_delete_domain(data);
 680                 else if (is_select)
 681                         domain = tomoyo_find_domain(data);
 682                 else
 683                         domain = tomoyo_find_or_assign_new_domain(data, 0);
 684                 head->write_var1 = domain;
 685                 return 0;
 686         }
 687         if (!domain)
 688                 return -EINVAL;
 689
 690         if (sscanf(data, TOMOYO_KEYWORD_USE_PROFILE "%u", &profile) == 1
 691             && profile < TOMOYO_MAX_PROFILES) {
 692                 if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
 693                         domain->profile = (u8) profile;
 694                 return 0;
 695         }
 696         if (!strcmp(data, TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
 697                 domain->ignore_global_allow_read = !is_delete;
 698                 return 0;
 699         }
 700         return tomoyo_write_domain_policy2(data, domain, is_delete);
 701 }
 702
 703 /**
 704  * tomoyo_print_path_acl - Print a single path ACL entry.
 705  *
 706  * @head: Pointer to "struct tomoyo_io_buffer".
 707  * @ptr:  Pointer to "struct tomoyo_path_acl".
 708  *
 709  * Returns true on success, false otherwise.
 710  */
 711 static bool tomoyo_print_path_acl(struct tomoyo_io_buffer *head,
 712                                   struct tomoyo_path_acl *ptr)
 713 {
 714         int pos;
 715         u8 bit;
 716         const u16 perm = ptr->perm;
 717
 718         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
 719                 if (!(perm & (1 << bit)))
 720                         continue;
 721                 /* Print "read/write" instead of "read" and "write". */
 722                 if ((bit == TOMOYO_TYPE_READ || bit == TOMOYO_TYPE_WRITE)
 723                     && (perm & (1 << TOMOYO_TYPE_READ_WRITE)))
 724                         continue;
 725                 pos = head->read_avail;
 726                 if (!tomoyo_io_printf(head, "allow_%s ",
 727                                       tomoyo_path2keyword(bit)) ||
 728                     !tomoyo_print_name_union(head, &ptr->name) ||
 729                     !tomoyo_io_printf(head, "\n"))
 730                         goto out;
 731         }
 732         head->read_bit = 0;
 733         return true;
 734  out:
 735         head->read_bit = bit;
 736         head->read_avail = pos;
 737         return false;
 738 }
 739
 740 /**
 741  * tomoyo_print_path2_acl - Print a double path ACL entry.
 742  *
 743  * @head: Pointer to "struct tomoyo_io_buffer".
 744  * @ptr:  Pointer to "struct tomoyo_path2_acl".
 745  *
 746  * Returns true on success, false otherwise.
 747  */
 748 static bool tomoyo_print_path2_acl(struct tomoyo_io_buffer *head,
 749                                    struct tomoyo_path2_acl *ptr)
 750 {
 751         int pos;
 752         const u8 perm = ptr->perm;
 753         u8 bit;
 754
 755         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
 756                 if (!(perm & (1 << bit)))
 757                         continue;
 758                 pos = head->read_avail;
 759                 if (!tomoyo_io_printf(head, "allow_%s ",
 760                                       tomoyo_path22keyword(bit)) ||
 761                     !tomoyo_print_name_union(head, &ptr->name1) ||
 762                     !tomoyo_print_name_union(head, &ptr->name2) ||
 763                     !tomoyo_io_printf(head, "\n"))
 764                         goto out;
 765         }
 766         head->read_bit = 0;
 767         return true;
 768  out:
 769         head->read_bit = bit;
 770         head->read_avail = pos;
 771         return false;
 772 }
 773
 774 /**
 775  * tomoyo_print_path_number_acl - Print a path_number ACL entry.
 776  *
 777  * @head: Pointer to "struct tomoyo_io_buffer".
 778  * @ptr:  Pointer to "struct tomoyo_path_number_acl".
 779  *
 780  * Returns true on success, false otherwise.
 781  */
 782 static bool tomoyo_print_path_number_acl(struct tomoyo_io_buffer *head,
 783                                          struct tomoyo_path_number_acl *ptr)
 784 {
 785         int pos;
 786         u8 bit;
 787         const u8 perm = ptr->perm;
 788         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION;
 789              bit++) {
 790                 if (!(perm & (1 << bit)))
 791                         continue;
 792                 pos = head->read_avail;
 793                 if (!tomoyo_io_printf(head, "allow_%s",
 794                                       tomoyo_path_number2keyword(bit)) ||
 795                     !tomoyo_print_name_union(head, &ptr->name) ||
 796                     !tomoyo_print_number_union(head, &ptr->number) ||
 797                     !tomoyo_io_printf(head, "\n"))
 798                         goto out;
 799         }
 800         head->read_bit = 0;
 801         return true;
 802  out:
 803         head->read_bit = bit;
 804         head->read_avail = pos;
 805         return false;
 806 }
 807
 808 /**
 809  * tomoyo_print_path_number3_acl - Print a path_number3 ACL entry.
 810  *
 811  * @head: Pointer to "struct tomoyo_io_buffer".
 812  * @ptr:  Pointer to "struct tomoyo_path_number3_acl".
 813  *
 814  * Returns true on success, false otherwise.
 815  */
 816 static bool tomoyo_print_path_number3_acl(struct tomoyo_io_buffer *head,
 817                                           struct tomoyo_path_number3_acl *ptr)
 818 {
 819         int pos;
 820         u8 bit;
 821         const u16 perm = ptr->perm;
 822         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_NUMBER3_OPERATION;
 823              bit++) {
 824                 if (!(perm & (1 << bit)))
 825                         continue;
 826                 pos = head->read_avail;
 827                 if (!tomoyo_io_printf(head, "allow_%s",
 828                                       tomoyo_path_number32keyword(bit)) ||
 829                     !tomoyo_print_name_union(head, &ptr->name) ||
 830                     !tomoyo_print_number_union(head, &ptr->mode) ||
 831                     !tomoyo_print_number_union(head, &ptr->major) ||
 832                     !tomoyo_print_number_union(head, &ptr->minor) ||
 833                     !tomoyo_io_printf(head, "\n"))
 834                         goto out;
 835         }
 836         head->read_bit = 0;
 837         return true;
 838  out:
 839         head->read_bit = bit;
 840         head->read_avail = pos;
 841         return false;
 842 }
 843
 844 /**
 845  * tomoyo_print_mount_acl - Print a mount ACL entry.
 846  *
 847  * @head: Pointer to "struct tomoyo_io_buffer".
 848  * @ptr:  Pointer to "struct tomoyo_mount_acl".
 849  *
 850  * Returns true on success, false otherwise.
 851  */
 852 static bool tomoyo_print_mount_acl(struct tomoyo_io_buffer *head,
 853                                    struct tomoyo_mount_acl *ptr)
 854 {
 855         const int pos = head->read_avail;
 856         if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_MOUNT) ||
 857             !tomoyo_print_name_union(head, &ptr->dev_name) ||
 858             !tomoyo_print_name_union(head, &ptr->dir_name) ||
 859             !tomoyo_print_name_union(head, &ptr->fs_type) ||
 860             !tomoyo_print_number_union(head, &ptr->flags) ||
 861             !tomoyo_io_printf(head, "\n")) {
 862                 head->read_avail = pos;
 863                 return false;
 864         }
 865         return true;
 866 }
 867
 868 /**
 869  * tomoyo_print_entry - Print an ACL entry.
 870  *
 871  * @head: Pointer to "struct tomoyo_io_buffer".
 872  * @ptr:  Pointer to an ACL entry.
 873  *
 874  * Returns true on success, false otherwise.
 875  */
 876 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
 877                                struct tomoyo_acl_info *ptr)
 878 {
 879         const u8 acl_type = ptr->type;
 880
 881         if (acl_type == TOMOYO_TYPE_PATH_ACL) {
 882                 struct tomoyo_path_acl *acl
 883                         = container_of(ptr, struct tomoyo_path_acl, head);
 884                 return tomoyo_print_path_acl(head, acl);
 885         }
 886         if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
 887                 struct tomoyo_path2_acl *acl
 888                         = container_of(ptr, struct tomoyo_path2_acl, head);
 889                 return tomoyo_print_path2_acl(head, acl);
 890         }
 891         if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
 892                 struct tomoyo_path_number_acl *acl
 893                         = container_of(ptr, struct tomoyo_path_number_acl,
 894                                        head);
 895                 return tomoyo_print_path_number_acl(head, acl);
 896         }
 897         if (acl_type == TOMOYO_TYPE_PATH_NUMBER3_ACL) {
 898                 struct tomoyo_path_number3_acl *acl
 899                         = container_of(ptr, struct tomoyo_path_number3_acl,
 900                                        head);
 901                 return tomoyo_print_path_number3_acl(head, acl);
 902         }
 903         if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
 904                 struct tomoyo_mount_acl *acl
 905                         = container_of(ptr, struct tomoyo_mount_acl, head);
 906                 return tomoyo_print_mount_acl(head, acl);
 907         }
 908         BUG(); /* This must not happen. */
 909         return false;
 910 }
 911
 912 /**
 913  * tomoyo_read_domain_policy - Read domain policy.
 914  *
 915  * @head: Pointer to "struct tomoyo_io_buffer".
 916  *
 917  * Returns 0.
 918  *
 919  * Caller holds tomoyo_read_lock().
 920  */
 921 static int tomoyo_read_domain_policy(struct tomoyo_io_buffer *head)
 922 {
 923         struct list_head *dpos;
 924         struct list_head *apos;
 925         bool done = true;
 926
 927         if (head->read_eof)
 928                 return 0;
 929         if (head->read_step == 0)
 930                 head->read_step = 1;
 931         list_for_each_cookie(dpos, head->read_var1, &tomoyo_domain_list) {
 932                 struct tomoyo_domain_info *domain;
 933                 const char *quota_exceeded = "";
 934                 const char *transition_failed = "";
 935                 const char *ignore_global_allow_read = "";
 936                 domain = list_entry(dpos, struct tomoyo_domain_info, list);
 937                 if (head->read_step != 1)
 938                         goto acl_loop;
 939                 if (domain->is_deleted && !head->read_single_domain)
 940                         continue;
 941                 /* Print domainname and flags. */
 942                 if (domain->quota_warned)
 943                         quota_exceeded = "quota_exceeded\n";
 944                 if (domain->transition_failed)
 945                         transition_failed = "transition_failed\n";
 946                 if (domain->ignore_global_allow_read)
 947                         ignore_global_allow_read
 948                                 = TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n";
 949                 done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE
 950                                         "%u\n%s%s%s\n",
 951                                         domain->domainname->name,
 952                                         domain->profile, quota_exceeded,
 953                                         transition_failed,
 954                                         ignore_global_allow_read);
 955                 if (!done)
 956                         break;
 957                 head->read_step = 2;
 958 acl_loop:
 959                 if (head->read_step == 3)
 960                         goto tail_mark;
 961                 /* Print ACL entries in the domain. */
 962                 list_for_each_cookie(apos, head->read_var2,
 963                                      &domain->acl_info_list) {
 964                         struct tomoyo_acl_info *ptr
 965                                 = list_entry(apos, struct tomoyo_acl_info,
 966                                              list);
 967                         done = tomoyo_print_entry(head, ptr);
 968                         if (!done)
 969                                 break;
 970                 }
 971                 if (!done)
 972                         break;
 973                 head->read_step = 3;
 974 tail_mark:
 975                 done = tomoyo_io_printf(head, "\n");
 976                 if (!done)
 977                         break;
 978                 head->read_step = 1;
 979                 if (head->read_single_domain)
 980                         break;
 981         }
 982         head->read_eof = done;
 983         return 0;
 984 }
 985
 986 /**
 987  * tomoyo_write_domain_profile - Assign profile for specified domain.
 988  *
 989  * @head: Pointer to "struct tomoyo_io_buffer".
 990  *
 991  * Returns 0 on success, -EINVAL otherwise.
 992  *
 993  * This is equivalent to doing
 994  *
 995  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
 996  *     /usr/lib/ccs/loadpolicy -d
 997  *
 998  * Caller holds tomoyo_read_lock().
 999  */
1000 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
1001 {
1002         char *data = head->write_buf;
1003         char *cp = strchr(data, ' ');
1004         struct tomoyo_domain_info *domain;
1005         unsigned long profile;
1006
1007         if (!cp)
1008                 return -EINVAL;
1009         *cp = '\0';
1010         domain = tomoyo_find_domain(cp + 1);
1011         if (strict_strtoul(data, 10, &profile))
1012                 return -EINVAL;
1013         if (domain && profile < TOMOYO_MAX_PROFILES
1014             && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
1015                 domain->profile = (u8) profile;
1016         return 0;
1017 }
1018
1019 /**
1020  * tomoyo_read_domain_profile - Read only domainname and profile.
1021  *
1022  * @head: Pointer to "struct tomoyo_io_buffer".
1023  *
1024  * Returns list of profile number and domainname pairs.
1025  *
1026  * This is equivalent to doing
1027  *
1028  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
1029  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
1030  *     domainname = $0; } else if ( $1 == "use_profile" ) {
1031  *     print $2 " " domainname; domainname = ""; } } ; '
1032  *
1033  * Caller holds tomoyo_read_lock().
1034  */
1035 static int tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
1036 {
1037         struct list_head *pos;
1038         bool done = true;
1039
1040         if (head->read_eof)
1041                 return 0;
1042         list_for_each_cookie(pos, head->read_var1, &tomoyo_domain_list) {
1043                 struct tomoyo_domain_info *domain;
1044                 domain = list_entry(pos, struct tomoyo_domain_info, list);
1045                 if (domain->is_deleted)
1046                         continue;
1047                 done = tomoyo_io_printf(head, "%u %s\n", domain->profile,
1048                                         domain->domainname->name);
1049                 if (!done)
1050                         break;
1051         }
1052         head->read_eof = done;
1053         return 0;
1054 }
1055
1056 /**
1057  * tomoyo_write_pid: Specify PID to obtain domainname.
1058  *
1059  * @head: Pointer to "struct tomoyo_io_buffer".
1060  *
1061  * Returns 0.
1062  */
1063 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1064 {
1065         unsigned long pid;
1066         /* No error check. */
1067         strict_strtoul(head->write_buf, 10, &pid);
1068         head->read_step = (int) pid;
1069         head->read_eof = false;
1070         return 0;
1071 }
1072
1073 /**
1074  * tomoyo_read_pid - Get domainname of the specified PID.
1075  *
1076  * @head: Pointer to "struct tomoyo_io_buffer".
1077  *
1078  * Returns the domainname which the specified PID is in on success,
1079  * empty string otherwise.
1080  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1081  * using read()/write() interface rather than sysctl() interface.
1082  */
1083 static int tomoyo_read_pid(struct tomoyo_io_buffer *head)
1084 {
1085         if (head->read_avail == 0 && !head->read_eof) {
1086                 const int pid = head->read_step;
1087                 struct task_struct *p;
1088                 struct tomoyo_domain_info *domain = NULL;
1089                 rcu_read_lock();
1090                 read_lock(&tasklist_lock);
1091                 p = find_task_by_vpid(pid);
1092                 if (p)
1093                         domain = tomoyo_real_domain(p);
1094                 read_unlock(&tasklist_lock);
1095                 rcu_read_unlock();
1096                 if (domain)
1097                         tomoyo_io_printf(head, "%d %u %s", pid, domain->profile,
1098                                          domain->domainname->name);
1099                 head->read_eof = true;
1100         }
1101         return 0;
1102 }
1103
1104 /**
1105  * tomoyo_write_exception_policy - Write exception policy.
1106  *
1107  * @head: Pointer to "struct tomoyo_io_buffer".
1108  *
1109  * Returns 0 on success, negative value otherwise.
1110  *
1111  * Caller holds tomoyo_read_lock().
1112  */
1113 static int tomoyo_write_exception_policy(struct tomoyo_io_buffer *head)
1114 {
1115         char *data = head->write_buf;
1116         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
1117
1118         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_KEEP_DOMAIN))
1119                 return tomoyo_write_domain_keeper_policy(data, false,
1120                                                          is_delete);
1121         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_KEEP_DOMAIN))
1122                 return tomoyo_write_domain_keeper_policy(data, true, is_delete);
1123         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_INITIALIZE_DOMAIN))
1124                 return tomoyo_write_domain_initializer_policy(data, false,
1125                                                               is_delete);
1126         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN))
1127                 return tomoyo_write_domain_initializer_policy(data, true,
1128                                                               is_delete);
1129         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALIAS))
1130                 return tomoyo_write_alias_policy(data, is_delete);
1131         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_READ))
1132                 return tomoyo_write_globally_readable_policy(data, is_delete);
1133         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_FILE_PATTERN))
1134                 return tomoyo_write_pattern_policy(data, is_delete);
1135         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DENY_REWRITE))
1136                 return tomoyo_write_no_rewrite_policy(data, is_delete);
1137         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_PATH_GROUP))
1138                 return tomoyo_write_path_group_policy(data, is_delete);
1139         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NUMBER_GROUP))
1140                 return tomoyo_write_number_group_policy(data, is_delete);
1141         return -EINVAL;
1142 }
1143
1144 /**
1145  * tomoyo_read_exception_policy - Read exception policy.
1146  *
1147  * @head: Pointer to "struct tomoyo_io_buffer".
1148  *
1149  * Returns 0 on success, -EINVAL otherwise.
1150  *
1151  * Caller holds tomoyo_read_lock().
1152  */
1153 static int tomoyo_read_exception_policy(struct tomoyo_io_buffer *head)
1154 {
1155         if (!head->read_eof) {
1156                 switch (head->read_step) {
1157                 case 0:
1158                         head->read_var2 = NULL;
1159                         head->read_step = 1;
1160                 case 1:
1161                         if (!tomoyo_read_domain_keeper_policy(head))
1162                                 break;
1163                         head->read_var2 = NULL;
1164                         head->read_step = 2;
1165                 case 2:
1166                         if (!tomoyo_read_globally_readable_policy(head))
1167                                 break;
1168                         head->read_var2 = NULL;
1169                         head->read_step = 3;
1170                 case 3:
1171                         head->read_var2 = NULL;
1172                         head->read_step = 4;
1173                 case 4:
1174                         if (!tomoyo_read_domain_initializer_policy(head))
1175                                 break;
1176                         head->read_var2 = NULL;
1177                         head->read_step = 5;
1178                 case 5:
1179                         if (!tomoyo_read_alias_policy(head))
1180                                 break;
1181                         head->read_var2 = NULL;
1182                         head->read_step = 6;
1183                 case 6:
1184                         head->read_var2 = NULL;
1185                         head->read_step = 7;
1186                 case 7:
1187                         if (!tomoyo_read_file_pattern(head))
1188                                 break;
1189                         head->read_var2 = NULL;
1190                         head->read_step = 8;
1191                 case 8:
1192                         if (!tomoyo_read_no_rewrite_policy(head))
1193                                 break;
1194                         head->read_var2 = NULL;
1195                         head->read_step = 9;
1196                 case 9:
1197                         if (!tomoyo_read_path_group_policy(head))
1198                                 break;
1199                         head->read_var1 = NULL;
1200                         head->read_var2 = NULL;
1201                         head->read_step = 10;
1202                 case 10:
1203                         if (!tomoyo_read_number_group_policy(head))
1204                                 break;
1205                         head->read_var1 = NULL;
1206                         head->read_var2 = NULL;
1207                         head->read_step = 11;
1208                 case 11:
1209                         head->read_eof = true;
1210                         break;
1211                 default:
1212                         return -EINVAL;
1213                 }
1214         }
1215         return 0;
1216 }
1217
1218 /**
1219  * tomoyo_print_header - Get header line of audit log.
1220  *
1221  * @r: Pointer to "struct tomoyo_request_info".
1222  *
1223  * Returns string representation.
1224  *
1225  * This function uses kmalloc(), so caller must kfree() if this function
1226  * didn't return NULL.
1227  */
1228 static char *tomoyo_print_header(struct tomoyo_request_info *r)
1229 {
1230         static const char *tomoyo_mode_4[4] = {
1231                 "disabled", "learning", "permissive", "enforcing"
1232         };
1233         struct timeval tv;
1234         const pid_t gpid = task_pid_nr(current);
1235         static const int tomoyo_buffer_len = 4096;
1236         char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
1237         if (!buffer)
1238                 return NULL;
1239         do_gettimeofday(&tv);
1240         snprintf(buffer, tomoyo_buffer_len - 1,
1241                  "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
1242                  " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
1243                  " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
1244                  tv.tv_sec, r->profile, tomoyo_mode_4[r->mode], gpid,
1245                  (pid_t) sys_getpid(), (pid_t) sys_getppid(),
1246                  current_uid(), current_gid(), current_euid(),
1247                  current_egid(), current_suid(), current_sgid(),
1248                  current_fsuid(), current_fsgid());
1249         return buffer;
1250 }
1251
1252 /**
1253  * tomoyo_init_audit_log - Allocate buffer for audit logs.
1254  *
1255  * @len: Required size.
1256  * @r:   Pointer to "struct tomoyo_request_info".
1257  *
1258  * Returns pointer to allocated memory.
1259  *
1260  * The @len is updated to add the header lines' size on success.
1261  *
1262  * This function uses kzalloc(), so caller must kfree() if this function
1263  * didn't return NULL.
1264  */
1265 static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r)
1266 {
1267         char *buf = NULL;
1268         const char *header;
1269         const char *domainname;
1270         if (!r->domain)
1271                 r->domain = tomoyo_domain();
1272         domainname = r->domain->domainname->name;
1273         header = tomoyo_print_header(r);
1274         if (!header)
1275                 return NULL;
1276         *len += strlen(domainname) + strlen(header) + 10;
1277         buf = kzalloc(*len, GFP_NOFS);
1278         if (buf)
1279                 snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname);
1280         kfree(header);
1281         return buf;
1282 }
1283
1284 /* Wait queue for tomoyo_query_list. */
1285 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1286
1287 /* Lock for manipulating tomoyo_query_list. */
1288 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1289
1290 /* Structure for query. */
1291 struct tomoyo_query_entry {
1292         struct list_head list;
1293         char *query;
1294         int query_len;
1295         unsigned int serial;
1296         int timer;
1297         int answer;
1298 };
1299
1300 /* The list for "struct tomoyo_query_entry". */
1301 static LIST_HEAD(tomoyo_query_list);
1302
1303 /*
1304  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1305  * interface.
1306  */
1307 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1308
1309 /**
1310  * tomoyo_supervisor - Ask for the supervisor's decision.
1311  *
1312  * @r:       Pointer to "struct tomoyo_request_info".
1313  * @fmt:     The printf()'s format string, followed by parameters.
1314  *
1315  * Returns 0 if the supervisor decided to permit the access request which
1316  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1317  * supervisor decided to retry the access request which violated the policy in
1318  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1319  */
1320 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1321 {
1322         va_list args;
1323         int error = -EPERM;
1324         int pos;
1325         int len;
1326         static unsigned int tomoyo_serial;
1327         struct tomoyo_query_entry *tomoyo_query_entry = NULL;
1328         bool quota_exceeded = false;
1329         char *header;
1330         switch (r->mode) {
1331                 char *buffer;
1332         case TOMOYO_CONFIG_LEARNING:
1333                 if (!tomoyo_domain_quota_is_ok(r))
1334                         return 0;
1335                 va_start(args, fmt);
1336                 len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4;
1337                 va_end(args);
1338                 buffer = kmalloc(len, GFP_NOFS);
1339                 if (!buffer)
1340                         return 0;
1341                 va_start(args, fmt);
1342                 vsnprintf(buffer, len - 1, fmt, args);
1343                 va_end(args);
1344                 tomoyo_normalize_line(buffer);
1345                 tomoyo_write_domain_policy2(buffer, r->domain, false);
1346                 kfree(buffer);
1347                 /* fall through */
1348         case TOMOYO_CONFIG_PERMISSIVE:
1349                 return 0;
1350         }
1351         if (!r->domain)
1352                 r->domain = tomoyo_domain();
1353         if (!atomic_read(&tomoyo_query_observers))
1354                 return -EPERM;
1355         va_start(args, fmt);
1356         len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
1357         va_end(args);
1358         header = tomoyo_init_audit_log(&len, r);
1359         if (!header)
1360                 goto out;
1361         tomoyo_query_entry = kzalloc(sizeof(*tomoyo_query_entry), GFP_NOFS);
1362         if (!tomoyo_query_entry)
1363                 goto out;
1364         tomoyo_query_entry->query = kzalloc(len, GFP_NOFS);
1365         if (!tomoyo_query_entry->query)
1366                 goto out;
1367         len = ksize(tomoyo_query_entry->query);
1368         INIT_LIST_HEAD(&tomoyo_query_entry->list);
1369         spin_lock(&tomoyo_query_list_lock);
1370         if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
1371             sizeof(*tomoyo_query_entry) >= tomoyo_quota_for_query) {
1372                 quota_exceeded = true;
1373         } else {
1374                 tomoyo_query_memory_size += len + sizeof(*tomoyo_query_entry);
1375                 tomoyo_query_entry->serial = tomoyo_serial++;
1376         }
1377         spin_unlock(&tomoyo_query_list_lock);
1378         if (quota_exceeded)
1379                 goto out;
1380         pos = snprintf(tomoyo_query_entry->query, len - 1, "Q%u-%hu\n%s",
1381                        tomoyo_query_entry->serial, r->retry, header);
1382         kfree(header);
1383         header = NULL;
1384         va_start(args, fmt);
1385         vsnprintf(tomoyo_query_entry->query + pos, len - 1 - pos, fmt, args);
1386         tomoyo_query_entry->query_len = strlen(tomoyo_query_entry->query) + 1;
1387         va_end(args);
1388         spin_lock(&tomoyo_query_list_lock);
1389         list_add_tail(&tomoyo_query_entry->list, &tomoyo_query_list);
1390         spin_unlock(&tomoyo_query_list_lock);
1391         /* Give 10 seconds for supervisor's opinion. */
1392         for (tomoyo_query_entry->timer = 0;
1393              atomic_read(&tomoyo_query_observers) && tomoyo_query_entry->timer < 100;
1394              tomoyo_query_entry->timer++) {
1395                 wake_up(&tomoyo_query_wait);
1396                 set_current_state(TASK_INTERRUPTIBLE);
1397                 schedule_timeout(HZ / 10);
1398                 if (tomoyo_query_entry->answer)
1399                         break;
1400         }
1401         spin_lock(&tomoyo_query_list_lock);
1402         list_del(&tomoyo_query_entry->list);
1403         tomoyo_query_memory_size -= len + sizeof(*tomoyo_query_entry);
1404         spin_unlock(&tomoyo_query_list_lock);
1405         switch (tomoyo_query_entry->answer) {
1406         case 3: /* Asked to retry by administrator. */
1407                 error = TOMOYO_RETRY_REQUEST;
1408                 r->retry++;
1409                 break;
1410         case 1:
1411                 /* Granted by administrator. */
1412                 error = 0;
1413                 break;
1414         case 0:
1415                 /* Timed out. */
1416                 break;
1417         default:
1418                 /* Rejected by administrator. */
1419                 break;
1420         }
1421  out:
1422         if (tomoyo_query_entry)
1423                 kfree(tomoyo_query_entry->query);
1424         kfree(tomoyo_query_entry);
1425         kfree(header);
1426         return error;
1427 }
1428
1429 /**
1430  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1431  *
1432  * @file: Pointer to "struct file".
1433  * @wait: Pointer to "poll_table".
1434  *
1435  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1436  *
1437  * Waits for access requests which violated policy in enforcing mode.
1438  */
1439 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1440 {
1441         struct list_head *tmp;
1442         bool found = false;
1443         u8 i;
1444         for (i = 0; i < 2; i++) {
1445                 spin_lock(&tomoyo_query_list_lock);
1446                 list_for_each(tmp, &tomoyo_query_list) {
1447                         struct tomoyo_query_entry *ptr
1448                                 = list_entry(tmp, struct tomoyo_query_entry,
1449                                              list);
1450                         if (ptr->answer)
1451                                 continue;
1452                         found = true;
1453                         break;
1454                 }
1455                 spin_unlock(&tomoyo_query_list_lock);
1456                 if (found)
1457                         return POLLIN | POLLRDNORM;
1458                 if (i)
1459                         break;
1460                 poll_wait(file, &tomoyo_query_wait, wait);
1461         }
1462         return 0;
1463 }
1464
1465 /**
1466  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1467  *
1468  * @head: Pointer to "struct tomoyo_io_buffer".
1469  *
1470  * Returns 0.
1471  */
1472 static int tomoyo_read_query(struct tomoyo_io_buffer *head)
1473 {
1474         struct list_head *tmp;
1475         int pos = 0;
1476         int len = 0;
1477         char *buf;
1478         if (head->read_avail)
1479                 return 0;
1480         if (head->read_buf) {
1481                 kfree(head->read_buf);
1482                 head->read_buf = NULL;
1483                 head->readbuf_size = 0;
1484         }
1485         spin_lock(&tomoyo_query_list_lock);
1486         list_for_each(tmp, &tomoyo_query_list) {
1487                 struct tomoyo_query_entry *ptr
1488                         = list_entry(tmp, struct tomoyo_query_entry, list);
1489                 if (ptr->answer)
1490                         continue;
1491                 if (pos++ != head->read_step)
1492                         continue;
1493                 len = ptr->query_len;
1494                 break;
1495         }
1496         spin_unlock(&tomoyo_query_list_lock);
1497         if (!len) {
1498                 head->read_step = 0;
1499                 return 0;
1500         }
1501         buf = kzalloc(len, GFP_NOFS);
1502         if (!buf)
1503                 return 0;
1504         pos = 0;
1505         spin_lock(&tomoyo_query_list_lock);
1506         list_for_each(tmp, &tomoyo_query_list) {
1507                 struct tomoyo_query_entry *ptr
1508                         = list_entry(tmp, struct tomoyo_query_entry, list);
1509                 if (ptr->answer)
1510                         continue;
1511                 if (pos++ != head->read_step)
1512                         continue;
1513                 /*
1514                  * Some query can be skipped because tomoyo_query_list
1515                  * can change, but I don't care.
1516                  */
1517                 if (len == ptr->query_len)
1518                         memmove(buf, ptr->query, len);
1519                 break;
1520         }
1521         spin_unlock(&tomoyo_query_list_lock);
1522         if (buf[0]) {
1523                 head->read_avail = len;
1524                 head->readbuf_size = head->read_avail;
1525                 head->read_buf = buf;
1526                 head->read_step++;
1527         } else {
1528                 kfree(buf);
1529         }
1530         return 0;
1531 }
1532
1533 /**
1534  * tomoyo_write_answer - Write the supervisor's decision.
1535  *
1536  * @head: Pointer to "struct tomoyo_io_buffer".
1537  *
1538  * Returns 0 on success, -EINVAL otherwise.
1539  */
1540 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1541 {
1542         char *data = head->write_buf;
1543         struct list_head *tmp;
1544         unsigned int serial;
1545         unsigned int answer;
1546         spin_lock(&tomoyo_query_list_lock);
1547         list_for_each(tmp, &tomoyo_query_list) {
1548                 struct tomoyo_query_entry *ptr
1549                         = list_entry(tmp, struct tomoyo_query_entry, list);
1550                 ptr->timer = 0;
1551         }
1552         spin_unlock(&tomoyo_query_list_lock);
1553         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1554                 return -EINVAL;
1555         spin_lock(&tomoyo_query_list_lock);
1556         list_for_each(tmp, &tomoyo_query_list) {
1557                 struct tomoyo_query_entry *ptr
1558                         = list_entry(tmp, struct tomoyo_query_entry, list);
1559                 if (ptr->serial != serial)
1560                         continue;
1561                 if (!ptr->answer)
1562                         ptr->answer = answer;
1563                 break;
1564         }
1565         spin_unlock(&tomoyo_query_list_lock);
1566         return 0;
1567 }
1568
1569 /**
1570  * tomoyo_read_version: Get version.
1571  *
1572  * @head: Pointer to "struct tomoyo_io_buffer".
1573  *
1574  * Returns version information.
1575  */
1576 static int tomoyo_read_version(struct tomoyo_io_buffer *head)
1577 {
1578         if (!head->read_eof) {
1579                 tomoyo_io_printf(head, "2.2.0");
1580                 head->read_eof = true;
1581         }
1582         return 0;
1583 }
1584
1585 /**
1586  * tomoyo_read_self_domain - Get the current process's domainname.
1587  *
1588  * @head: Pointer to "struct tomoyo_io_buffer".
1589  *
1590  * Returns the current process's domainname.
1591  */
1592 static int tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1593 {
1594         if (!head->read_eof) {
1595                 /*
1596                  * tomoyo_domain()->domainname != NULL
1597                  * because every process belongs to a domain and
1598                  * the domain's name cannot be NULL.
1599                  */
1600                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1601                 head->read_eof = true;
1602         }
1603         return 0;
1604 }
1605
1606 /**
1607  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1608  *
1609  * @type: Type of interface.
1610  * @file: Pointer to "struct file".
1611  *
1612  * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
1613  *
1614  * Caller acquires tomoyo_read_lock().
1615  */
1616 int tomoyo_open_control(const u8 type, struct file *file)
1617 {
1618         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1619
1620         if (!head)
1621                 return -ENOMEM;
1622         mutex_init(&head->io_sem);
1623         head->type = type;
1624         switch (type) {
1625         case TOMOYO_DOMAINPOLICY:
1626                 /* /sys/kernel/security/tomoyo/domain_policy */
1627                 head->write = tomoyo_write_domain_policy;
1628                 head->read = tomoyo_read_domain_policy;
1629                 break;
1630         case TOMOYO_EXCEPTIONPOLICY:
1631                 /* /sys/kernel/security/tomoyo/exception_policy */
1632                 head->write = tomoyo_write_exception_policy;
1633                 head->read = tomoyo_read_exception_policy;
1634                 break;
1635         case TOMOYO_SELFDOMAIN:
1636                 /* /sys/kernel/security/tomoyo/self_domain */
1637                 head->read = tomoyo_read_self_domain;
1638                 break;
1639         case TOMOYO_DOMAIN_STATUS:
1640                 /* /sys/kernel/security/tomoyo/.domain_status */
1641                 head->write = tomoyo_write_domain_profile;
1642                 head->read = tomoyo_read_domain_profile;
1643                 break;
1644         case TOMOYO_PROCESS_STATUS:
1645                 /* /sys/kernel/security/tomoyo/.process_status */
1646                 head->write = tomoyo_write_pid;
1647                 head->read = tomoyo_read_pid;
1648                 break;
1649         case TOMOYO_VERSION:
1650                 /* /sys/kernel/security/tomoyo/version */
1651                 head->read = tomoyo_read_version;
1652                 head->readbuf_size = 128;
1653                 break;
1654         case TOMOYO_MEMINFO:
1655                 /* /sys/kernel/security/tomoyo/meminfo */
1656                 head->write = tomoyo_write_memory_quota;
1657                 head->read = tomoyo_read_memory_counter;
1658                 head->readbuf_size = 512;
1659                 break;
1660         case TOMOYO_PROFILE:
1661                 /* /sys/kernel/security/tomoyo/profile */
1662                 head->write = tomoyo_write_profile;
1663                 head->read = tomoyo_read_profile;
1664                 break;
1665         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1666                 head->poll = tomoyo_poll_query;
1667                 head->write = tomoyo_write_answer;
1668                 head->read = tomoyo_read_query;
1669                 break;
1670         case TOMOYO_MANAGER:
1671                 /* /sys/kernel/security/tomoyo/manager */
1672                 head->write = tomoyo_write_manager_policy;
1673                 head->read = tomoyo_read_manager_policy;
1674                 break;
1675         }
1676         if (!(file->f_mode & FMODE_READ)) {
1677                 /*
1678                  * No need to allocate read_buf since it is not opened
1679                  * for reading.
1680                  */
1681                 head->read = NULL;
1682                 head->poll = NULL;
1683         } else if (!head->poll) {
1684                 /* Don't allocate read_buf for poll() access. */
1685                 if (!head->readbuf_size)
1686                         head->readbuf_size = 4096 * 2;
1687                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1688                 if (!head->read_buf) {
1689                         kfree(head);
1690                         return -ENOMEM;
1691                 }
1692         }
1693         if (!(file->f_mode & FMODE_WRITE)) {
1694                 /*
1695                  * No need to allocate write_buf since it is not opened
1696                  * for writing.
1697                  */
1698                 head->write = NULL;
1699         } else if (head->write) {
1700                 head->writebuf_size = 4096 * 2;
1701                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1702                 if (!head->write_buf) {
1703                         kfree(head->read_buf);
1704                         kfree(head);
1705                         return -ENOMEM;
1706                 }
1707         }
1708         if (type != TOMOYO_QUERY)
1709                 head->reader_idx = tomoyo_read_lock();
1710         file->private_data = head;
1711         /*
1712          * Call the handler now if the file is
1713          * /sys/kernel/security/tomoyo/self_domain
1714          * so that the user can use
1715          * cat < /sys/kernel/security/tomoyo/self_domain"
1716          * to know the current process's domainname.
1717          */
1718         if (type == TOMOYO_SELFDOMAIN)
1719                 tomoyo_read_control(file, NULL, 0);
1720         /*
1721          * If the file is /sys/kernel/security/tomoyo/query , increment the
1722          * observer counter.
1723          * The obserber counter is used by tomoyo_supervisor() to see if
1724          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1725          */
1726         else if (type == TOMOYO_QUERY)
1727                 atomic_inc(&tomoyo_query_observers);
1728         return 0;
1729 }
1730
1731 /**
1732  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1733  *
1734  * @file: Pointer to "struct file".
1735  * @wait: Pointer to "poll_table".
1736  *
1737  * Waits for read readiness.
1738  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
1739  */
1740 int tomoyo_poll_control(struct file *file, poll_table *wait)
1741 {
1742         struct tomoyo_io_buffer *head = file->private_data;
1743         if (!head->poll)
1744                 return -ENOSYS;
1745         return head->poll(file, wait);
1746 }
1747
1748 /**
1749  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
1750  *
1751  * @file:       Pointer to "struct file".
1752  * @buffer:     Poiner to buffer to write to.
1753  * @buffer_len: Size of @buffer.
1754  *
1755  * Returns bytes read on success, negative value otherwise.
1756  *
1757  * Caller holds tomoyo_read_lock().
1758  */
1759 int tomoyo_read_control(struct file *file, char __user *buffer,
1760                         const int buffer_len)
1761 {
1762         int len = 0;
1763         struct tomoyo_io_buffer *head = file->private_data;
1764         char *cp;
1765
1766         if (!head->read)
1767                 return -ENOSYS;
1768         if (mutex_lock_interruptible(&head->io_sem))
1769                 return -EINTR;
1770         /* Call the policy handler. */
1771         len = head->read(head);
1772         if (len < 0)
1773                 goto out;
1774         /* Write to buffer. */
1775         len = head->read_avail;
1776         if (len > buffer_len)
1777                 len = buffer_len;
1778         if (!len)
1779                 goto out;
1780         /* head->read_buf changes by some functions. */
1781         cp = head->read_buf;
1782         if (copy_to_user(buffer, cp, len)) {
1783                 len = -EFAULT;
1784                 goto out;
1785         }
1786         head->read_avail -= len;
1787         memmove(cp, cp + len, head->read_avail);
1788  out:
1789         mutex_unlock(&head->io_sem);
1790         return len;
1791 }
1792
1793 /**
1794  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
1795  *
1796  * @file:       Pointer to "struct file".
1797  * @buffer:     Pointer to buffer to read from.
1798  * @buffer_len: Size of @buffer.
1799  *
1800  * Returns @buffer_len on success, negative value otherwise.
1801  *
1802  * Caller holds tomoyo_read_lock().
1803  */
1804 int tomoyo_write_control(struct file *file, const char __user *buffer,
1805                          const int buffer_len)
1806 {
1807         struct tomoyo_io_buffer *head = file->private_data;
1808         int error = buffer_len;
1809         int avail_len = buffer_len;
1810         char *cp0 = head->write_buf;
1811
1812         if (!head->write)
1813                 return -ENOSYS;
1814         if (!access_ok(VERIFY_READ, buffer, buffer_len))
1815                 return -EFAULT;
1816         /* Don't allow updating policies by non manager programs. */
1817         if (head->write != tomoyo_write_pid &&
1818             head->write != tomoyo_write_domain_policy &&
1819             !tomoyo_is_policy_manager())
1820                 return -EPERM;
1821         if (mutex_lock_interruptible(&head->io_sem))
1822                 return -EINTR;
1823         /* Read a line and dispatch it to the policy handler. */
1824         while (avail_len > 0) {
1825                 char c;
1826                 if (head->write_avail >= head->writebuf_size - 1) {
1827                         error = -ENOMEM;
1828                         break;
1829                 } else if (get_user(c, buffer)) {
1830                         error = -EFAULT;
1831                         break;
1832                 }
1833                 buffer++;
1834                 avail_len--;
1835                 cp0[head->write_avail++] = c;
1836                 if (c != '\n')
1837                         continue;
1838                 cp0[head->write_avail - 1] = '\0';
1839                 head->write_avail = 0;
1840                 tomoyo_normalize_line(cp0);
1841                 head->write(head);
1842         }
1843         mutex_unlock(&head->io_sem);
1844         return error;
1845 }
1846
1847 /**
1848  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
1849  *
1850  * @file: Pointer to "struct file".
1851  *
1852  * Releases memory and returns 0.
1853  *
1854  * Caller looses tomoyo_read_lock().
1855  */
1856 int tomoyo_close_control(struct file *file)
1857 {
1858         struct tomoyo_io_buffer *head = file->private_data;
1859         const bool is_write = !!head->write_buf;
1860
1861         /*
1862          * If the file is /sys/kernel/security/tomoyo/query , decrement the
1863          * observer counter.
1864          */
1865         if (head->type == TOMOYO_QUERY)
1866                 atomic_dec(&tomoyo_query_observers);
1867         else
1868                 tomoyo_read_unlock(head->reader_idx);
1869         /* Release memory used for policy I/O. */
1870         kfree(head->read_buf);
1871         head->read_buf = NULL;
1872         kfree(head->write_buf);
1873         head->write_buf = NULL;
1874         kfree(head);
1875         head = NULL;
1876         file->private_data = NULL;
1877         if (is_write)
1878                 tomoyo_run_gc();
1879         return 0;
1880 }
1881
1882 /**
1883  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
1884  */
1885 void tomoyo_check_profile(void)
1886 {
1887         struct tomoyo_domain_info *domain;
1888         const int idx = tomoyo_read_lock();
1889         tomoyo_policy_loaded = true;
1890         /* Check all profiles currently assigned to domains are defined. */
1891         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
1892                 const u8 profile = domain->profile;
1893                 if (tomoyo_profile_ptr[profile])
1894                         continue;
1895                 panic("Profile %u (used by '%s') not defined.\n",
1896                       profile, domain->domainname->name);
1897         }
1898         tomoyo_read_unlock(idx);
1899         printk(KERN_INFO "TOMOYO: 2.2.0   2009/04/01\n");
1900         printk(KERN_INFO "Mandatory Access Control activated.\n");
1901 }