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 "common.h"
  13
  14 /* Profile version. Currently only 20090903 is defined. */
  15 static unsigned int tomoyo_profile_version;
  16
  17 /* Profile table. Memory is allocated as needed. */
  18 static struct tomoyo_profile *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
  19
  20 /* String table for functionality that takes 4 modes. */
  21 static const char *tomoyo_mode[4] = {
  22         "disabled", "learning", "permissive", "enforcing"
  23 };
  24
  25 /* String table for /sys/kernel/security/tomoyo/profile */
  26 static const char *tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
  27                                        + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
  28         [TOMOYO_MAC_FILE_EXECUTE]    = "file::execute",
  29         [TOMOYO_MAC_FILE_OPEN]       = "file::open",
  30         [TOMOYO_MAC_FILE_CREATE]     = "file::create",
  31         [TOMOYO_MAC_FILE_UNLINK]     = "file::unlink",
  32         [TOMOYO_MAC_FILE_GETATTR]    = "file::getattr",
  33         [TOMOYO_MAC_FILE_MKDIR]      = "file::mkdir",
  34         [TOMOYO_MAC_FILE_RMDIR]      = "file::rmdir",
  35         [TOMOYO_MAC_FILE_MKFIFO]     = "file::mkfifo",
  36         [TOMOYO_MAC_FILE_MKSOCK]     = "file::mksock",
  37         [TOMOYO_MAC_FILE_TRUNCATE]   = "file::truncate",
  38         [TOMOYO_MAC_FILE_SYMLINK]    = "file::symlink",
  39         [TOMOYO_MAC_FILE_MKBLOCK]    = "file::mkblock",
  40         [TOMOYO_MAC_FILE_MKCHAR]     = "file::mkchar",
  41         [TOMOYO_MAC_FILE_LINK]       = "file::link",
  42         [TOMOYO_MAC_FILE_RENAME]     = "file::rename",
  43         [TOMOYO_MAC_FILE_CHMOD]      = "file::chmod",
  44         [TOMOYO_MAC_FILE_CHOWN]      = "file::chown",
  45         [TOMOYO_MAC_FILE_CHGRP]      = "file::chgrp",
  46         [TOMOYO_MAC_FILE_IOCTL]      = "file::ioctl",
  47         [TOMOYO_MAC_FILE_CHROOT]     = "file::chroot",
  48         [TOMOYO_MAC_FILE_MOUNT]      = "file::mount",
  49         [TOMOYO_MAC_FILE_UMOUNT]     = "file::unmount",
  50         [TOMOYO_MAC_FILE_PIVOT_ROOT] = "file::pivot_root",
  51         [TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
  52 };
  53
  54 /* String table for PREFERENCE keyword. */
  55 static const char * const tomoyo_pref_keywords[TOMOYO_MAX_PREF] = {
  56         [TOMOYO_PREF_MAX_LEARNING_ENTRY] = "max_learning_entry",
  57 };
  58
  59 /* Permit policy management by non-root user? */
  60 static bool tomoyo_manage_by_non_root;
  61
  62 /* Utility functions. */
  63
  64 /**
  65  * tomoyo_yesno - Return "yes" or "no".
  66  *
  67  * @value: Bool value.
  68  */
  69 /*
  70 static const char *tomoyo_yesno(const unsigned int value)
  71 {
  72         return value ? "yes" : "no";
  73 }
  74 */
  75
  76 /**
  77  * tomoyo_addprintf - strncat()-like-snprintf().
  78  *
  79  * @buffer: Buffer to write to. Must be '\0'-terminated.
  80  * @len:    Size of @buffer.
  81  * @fmt:    The printf()'s format string, followed by parameters.
  82  *
  83  * Returns nothing.
  84  */
  85 static void tomoyo_addprintf(char *buffer, int len, const char *fmt, ...)
  86 {
  87         va_list args;
  88         const int pos = strlen(buffer);
  89         va_start(args, fmt);
  90         vsnprintf(buffer + pos, len - pos - 1, fmt, args);
  91         va_end(args);
  92 }
  93
  94 /**
  95  * tomoyo_flush - Flush queued string to userspace's buffer.
  96  *
  97  * @head:   Pointer to "struct tomoyo_io_buffer".
  98  *
  99  * Returns true if all data was flushed, false otherwise.
 100  */
 101 static bool tomoyo_flush(struct tomoyo_io_buffer *head)
 102 {
 103         while (head->r.w_pos) {
 104                 const char *w = head->r.w[0];
 105                 int len = strlen(w);
 106                 if (len) {
 107                         if (len > head->read_user_buf_avail)
 108                                 len = head->read_user_buf_avail;
 109                         if (!len)
 110                                 return false;
 111                         if (copy_to_user(head->read_user_buf, w, len))
 112                                 return false;
 113                         head->read_user_buf_avail -= len;
 114                         head->read_user_buf += len;
 115                         w += len;
 116                 }
 117                 head->r.w[0] = w;
 118                 if (*w)
 119                         return false;
 120                 /* Add '\0' for query. */
 121                 if (head->poll) {
 122                         if (!head->read_user_buf_avail ||
 123                             copy_to_user(head->read_user_buf, "", 1))
 124                                 return false;
 125                         head->read_user_buf_avail--;
 126                         head->read_user_buf++;
 127                 }
 128                 head->r.w_pos--;
 129                 for (len = 0; len < head->r.w_pos; len++)
 130                         head->r.w[len] = head->r.w[len + 1];
 131         }
 132         head->r.avail = 0;
 133         return true;
 134 }
 135
 136 /**
 137  * tomoyo_set_string - Queue string to "struct tomoyo_io_buffer" structure.
 138  *
 139  * @head:   Pointer to "struct tomoyo_io_buffer".
 140  * @string: String to print.
 141  *
 142  * Note that @string has to be kept valid until @head is kfree()d.
 143  * This means that char[] allocated on stack memory cannot be passed to
 144  * this function. Use tomoyo_io_printf() for char[] allocated on stack memory.
 145  */
 146 static void tomoyo_set_string(struct tomoyo_io_buffer *head, const char *string)
 147 {
 148         if (head->r.w_pos < TOMOYO_MAX_IO_READ_QUEUE) {
 149                 head->r.w[head->r.w_pos++] = string;
 150                 tomoyo_flush(head);
 151         } else
 152                 WARN_ON(1);
 153 }
 154
 155 /**
 156  * tomoyo_io_printf - printf() to "struct tomoyo_io_buffer" structure.
 157  *
 158  * @head: Pointer to "struct tomoyo_io_buffer".
 159  * @fmt:  The printf()'s format string, followed by parameters.
 160  */
 161 void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
 162 {
 163         va_list args;
 164         int len;
 165         int pos = head->r.avail;
 166         int size = head->readbuf_size - pos;
 167         if (size <= 0)
 168                 return;
 169         va_start(args, fmt);
 170         len = vsnprintf(head->read_buf + pos, size, fmt, args) + 1;
 171         va_end(args);
 172         if (pos + len >= head->readbuf_size) {
 173                 WARN_ON(1);
 174                 return;
 175         }
 176         head->r.avail += len;
 177         tomoyo_set_string(head, head->read_buf + pos);
 178 }
 179
 180 /**
 181  * tomoyo_set_space - Put a space to "struct tomoyo_io_buffer" structure.
 182  *
 183  * @head: Pointer to "struct tomoyo_io_buffer".
 184  *
 185  * Returns nothing.
 186  */
 187 static void tomoyo_set_space(struct tomoyo_io_buffer *head)
 188 {
 189         tomoyo_set_string(head, " ");
 190 }
 191
 192 /**
 193  * tomoyo_set_lf - Put a line feed to "struct tomoyo_io_buffer" structure.
 194  *
 195  * @head: Pointer to "struct tomoyo_io_buffer".
 196  *
 197  * Returns nothing.
 198  */
 199 static bool tomoyo_set_lf(struct tomoyo_io_buffer *head)
 200 {
 201         tomoyo_set_string(head, "\n");
 202         return !head->r.w_pos;
 203 }
 204
 205 /**
 206  * tomoyo_set_slash - Put a shash to "struct tomoyo_io_buffer" structure.
 207  *
 208  * @head: Pointer to "struct tomoyo_io_buffer".
 209  *
 210  * Returns nothing.
 211  */
 212 static void tomoyo_set_slash(struct tomoyo_io_buffer *head)
 213 {
 214         tomoyo_set_string(head, "/");
 215 }
 216
 217 /**
 218  * tomoyo_print_name_union - Print a tomoyo_name_union.
 219  *
 220  * @head: Pointer to "struct tomoyo_io_buffer".
 221  * @ptr:  Pointer to "struct tomoyo_name_union".
 222  */
 223 static void tomoyo_print_name_union(struct tomoyo_io_buffer *head,
 224                                     const struct tomoyo_name_union *ptr)
 225 {
 226         tomoyo_set_space(head);
 227         if (ptr->group) {
 228                 tomoyo_set_string(head, "@");
 229                 tomoyo_set_string(head, ptr->group->group_name->name);
 230         } else {
 231                 tomoyo_set_string(head, ptr->filename->name);
 232         }
 233 }
 234
 235 /**
 236  * tomoyo_print_number_union - Print a tomoyo_number_union.
 237  *
 238  * @head:       Pointer to "struct tomoyo_io_buffer".
 239  * @ptr:        Pointer to "struct tomoyo_number_union".
 240  */
 241 static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
 242                                       const struct tomoyo_number_union *ptr)
 243 {
 244         tomoyo_set_space(head);
 245         if (ptr->group) {
 246                 tomoyo_set_string(head, "@");
 247                 tomoyo_set_string(head, ptr->group->group_name->name);
 248         } else {
 249                 int i;
 250                 unsigned long min = ptr->values[0];
 251                 const unsigned long max = ptr->values[1];
 252                 u8 min_type = ptr->value_type[0];
 253                 const u8 max_type = ptr->value_type[1];
 254                 char buffer[128];
 255                 buffer[0] = '\0';
 256                 for (i = 0; i < 2; i++) {
 257                         switch (min_type) {
 258                         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
 259                                 tomoyo_addprintf(buffer, sizeof(buffer),
 260                                                  "0x%lX", min);
 261                                 break;
 262                         case TOMOYO_VALUE_TYPE_OCTAL:
 263                                 tomoyo_addprintf(buffer, sizeof(buffer),
 264                                                  "0%lo", min);
 265                                 break;
 266                         default:
 267                                 tomoyo_addprintf(buffer, sizeof(buffer),
 268                                                  "%lu", min);
 269                                 break;
 270                         }
 271                         if (min == max && min_type == max_type)
 272                                 break;
 273                         tomoyo_addprintf(buffer, sizeof(buffer), "-");
 274                         min_type = max_type;
 275                         min = max;
 276                 }
 277                 tomoyo_io_printf(head, "%s", buffer);
 278         }
 279 }
 280
 281 /**
 282  * tomoyo_assign_profile - Create a new profile.
 283  *
 284  * @profile: Profile number to create.
 285  *
 286  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
 287  */
 288 static struct tomoyo_profile *tomoyo_assign_profile(const unsigned int profile)
 289 {
 290         struct tomoyo_profile *ptr;
 291         struct tomoyo_profile *entry;
 292         if (profile >= TOMOYO_MAX_PROFILES)
 293                 return NULL;
 294         ptr = tomoyo_profile_ptr[profile];
 295         if (ptr)
 296                 return ptr;
 297         entry = kzalloc(sizeof(*entry), GFP_NOFS);
 298         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 299                 goto out;
 300         ptr = tomoyo_profile_ptr[profile];
 301         if (!ptr && tomoyo_memory_ok(entry)) {
 302                 ptr = entry;
 303                 ptr->default_config = TOMOYO_CONFIG_DISABLED;
 304                 memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
 305                        sizeof(ptr->config));
 306                 ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] = 2048;
 307                 mb(); /* Avoid out-of-order execution. */
 308                 tomoyo_profile_ptr[profile] = ptr;
 309                 entry = NULL;
 310         }
 311         mutex_unlock(&tomoyo_policy_lock);
 312  out:
 313         kfree(entry);
 314         return ptr;
 315 }
 316
 317 /**
 318  * tomoyo_profile - Find a profile.
 319  *
 320  * @profile: Profile number to find.
 321  *
 322  * Returns pointer to "struct tomoyo_profile".
 323  */
 324 struct tomoyo_profile *tomoyo_profile(const u8 profile)
 325 {
 326         static struct tomoyo_profile tomoyo_null_profile;
 327         struct tomoyo_profile *ptr = tomoyo_profile_ptr[profile];
 328         if (!ptr)
 329                 ptr = &tomoyo_null_profile;
 330         return ptr;
 331 }
 332
 333 /**
 334  * tomoyo_find_yesno - Find values for specified keyword.
 335  *
 336  * @string: String to check.
 337  * @find:   Name of keyword.
 338  *
 339  * Returns 1 if "@find=yes" was found, 0 if "@find=no" was found, -1 otherwise.
 340  */
 341 /*
 342 static s8 tomoyo_find_yesno(const char *string, const char *find)
 343 {
 344         const char *cp = strstr(string, find);
 345         if (cp) {
 346                 cp += strlen(find);
 347                 if (!strncmp(cp, "=yes", 4))
 348                         return 1;
 349                 else if (!strncmp(cp, "=no", 3))
 350                         return 0;
 351         }
 352         return -1;
 353 }
 354 */
 355
 356 /**
 357  * tomoyo_set_uint - Set value for specified preference.
 358  *
 359  * @i:      Pointer to "unsigned int".
 360  * @string: String to check.
 361  * @find:   Name of keyword.
 362  *
 363  * Returns nothing.
 364  */
 365 static void tomoyo_set_uint(unsigned int *i, const char *string,
 366                             const char *find)
 367 {
 368         const char *cp = strstr(string, find);
 369         if (cp)
 370                 sscanf(cp + strlen(find), "=%u", i);
 371 }
 372
 373 /**
 374  * tomoyo_set_mode - Set mode for specified profile.
 375  *
 376  * @name:    Name of functionality.
 377  * @value:   Mode for @name.
 378  * @profile: Pointer to "struct tomoyo_profile".
 379  *
 380  * Returns 0 on success, negative value otherwise.
 381  */
 382 static int tomoyo_set_mode(char *name, const char *value,
 383                            struct tomoyo_profile *profile)
 384 {
 385         u8 i;
 386         u8 config;
 387         if (!strcmp(name, "CONFIG")) {
 388                 i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
 389                 config = profile->default_config;
 390         } else if (tomoyo_str_starts(&name, "CONFIG::")) {
 391                 config = 0;
 392                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX
 393                              + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
 394                         if (strcmp(name, tomoyo_mac_keywords[i]))
 395                                 continue;
 396                         config = profile->config[i];
 397                         break;
 398                 }
 399                 if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 400                         return -EINVAL;
 401         } else {
 402                 return -EINVAL;
 403         }
 404         if (strstr(value, "use_default")) {
 405                 config = TOMOYO_CONFIG_USE_DEFAULT;
 406         } else {
 407                 u8 mode;
 408                 for (mode = 0; mode < 4; mode++)
 409                         if (strstr(value, tomoyo_mode[mode]))
 410                                 /*
 411                                  * Update lower 3 bits in order to distinguish
 412                                  * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
 413                                  */
 414                                 config = (config & ~7) | mode;
 415         }
 416         if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
 417                 profile->config[i] = config;
 418         else if (config != TOMOYO_CONFIG_USE_DEFAULT)
 419                 profile->default_config = config;
 420         return 0;
 421 }
 422
 423 /**
 424  * tomoyo_write_profile - Write profile table.
 425  *
 426  * @head: Pointer to "struct tomoyo_io_buffer".
 427  *
 428  * Returns 0 on success, negative value otherwise.
 429  */
 430 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
 431 {
 432         char *data = head->write_buf;
 433         unsigned int i;
 434         char *cp;
 435         struct tomoyo_profile *profile;
 436         if (sscanf(data, "PROFILE_VERSION=%u", &tomoyo_profile_version) == 1)
 437                 return 0;
 438         i = simple_strtoul(data, &cp, 10);
 439         if (*cp != '-')
 440                 return -EINVAL;
 441         data = cp + 1;
 442         profile = tomoyo_assign_profile(i);
 443         if (!profile)
 444                 return -EINVAL;
 445         cp = strchr(data, '=');
 446         if (!cp)
 447                 return -EINVAL;
 448         *cp++ = '\0';
 449         if (!strcmp(data, "COMMENT")) {
 450                 static DEFINE_SPINLOCK(lock);
 451                 const struct tomoyo_path_info *new_comment
 452                         = tomoyo_get_name(cp);
 453                 const struct tomoyo_path_info *old_comment;
 454                 if (!new_comment)
 455                         return -ENOMEM;
 456                 spin_lock(&lock);
 457                 old_comment = profile->comment;
 458                 profile->comment = new_comment;
 459                 spin_unlock(&lock);
 460                 tomoyo_put_name(old_comment);
 461                 return 0;
 462         }
 463         if (!strcmp(data, "PREFERENCE")) {
 464                 for (i = 0; i < TOMOYO_MAX_PREF; i++)
 465                         tomoyo_set_uint(&profile->pref[i], cp,
 466                                         tomoyo_pref_keywords[i]);
 467                 return 0;
 468         }
 469         return tomoyo_set_mode(data, cp, profile);
 470 }
 471
 472 static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
 473 {
 474         tomoyo_io_printf(head, "={ mode=%s }\n", tomoyo_mode[config & 3]);
 475 }
 476
 477 /**
 478  * tomoyo_read_profile - Read profile table.
 479  *
 480  * @head: Pointer to "struct tomoyo_io_buffer".
 481  */
 482 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 483 {
 484         u8 index;
 485         const struct tomoyo_profile *profile;
 486  next:
 487         index = head->r.index;
 488         profile = tomoyo_profile_ptr[index];
 489         switch (head->r.step) {
 490         case 0:
 491                 tomoyo_io_printf(head, "PROFILE_VERSION=%s\n", "20090903");
 492                 head->r.step++;
 493                 break;
 494         case 1:
 495                 for ( ; head->r.index < TOMOYO_MAX_PROFILES;
 496                       head->r.index++)
 497                         if (tomoyo_profile_ptr[head->r.index])
 498                                 break;
 499                 if (head->r.index == TOMOYO_MAX_PROFILES)
 500                         return;
 501                 head->r.step++;
 502                 break;
 503         case 2:
 504                 {
 505                         u8 i;
 506                         const struct tomoyo_path_info *comment =
 507                                 profile->comment;
 508                         tomoyo_io_printf(head, "%u-COMMENT=", index);
 509                         tomoyo_set_string(head, comment ? comment->name : "");
 510                         tomoyo_set_lf(head);
 511                         tomoyo_io_printf(head, "%u-PREFERENCE={ ", index);
 512                         for (i = 0; i < TOMOYO_MAX_PREF; i++)
 513                                 tomoyo_io_printf(head, "%s=%u ",
 514                                                  tomoyo_pref_keywords[i],
 515                                                  profile->pref[i]);
 516                         tomoyo_set_string(head, "}\n");
 517                         head->r.step++;
 518                 }
 519                 break;
 520         case 3:
 521                 {
 522                         tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
 523                         tomoyo_print_config(head, profile->default_config);
 524                         head->r.bit = 0;
 525                         head->r.step++;
 526                 }
 527                 break;
 528         case 4:
 529                 for ( ; head->r.bit < TOMOYO_MAX_MAC_INDEX
 530                               + TOMOYO_MAX_MAC_CATEGORY_INDEX; head->r.bit++) {
 531                         const u8 i = head->r.bit;
 532                         const u8 config = profile->config[i];
 533                         if (config == TOMOYO_CONFIG_USE_DEFAULT)
 534                                 continue;
 535                         tomoyo_io_printf(head, "%u-%s%s", index, "CONFIG::",
 536                                          tomoyo_mac_keywords[i]);
 537                         tomoyo_print_config(head, config);
 538                         head->r.bit++;
 539                         break;
 540                 }
 541                 if (head->r.bit == TOMOYO_MAX_MAC_INDEX
 542                     + TOMOYO_MAX_MAC_CATEGORY_INDEX) {
 543                         head->r.index++;
 544                         head->r.step = 1;
 545                 }
 546                 break;
 547         }
 548         if (tomoyo_flush(head))
 549                 goto next;
 550 }
 551
 552 static bool tomoyo_same_manager(const struct tomoyo_acl_head *a,
 553                                 const struct tomoyo_acl_head *b)
 554 {
 555         return container_of(a, struct tomoyo_manager, head)->manager ==
 556                 container_of(b, struct tomoyo_manager, head)->manager;
 557 }
 558
 559 /**
 560  * tomoyo_update_manager_entry - Add a manager entry.
 561  *
 562  * @manager:   The path to manager or the domainnamme.
 563  * @is_delete: True if it is a delete request.
 564  *
 565  * Returns 0 on success, negative value otherwise.
 566  *
 567  * Caller holds tomoyo_read_lock().
 568  */
 569 static int tomoyo_update_manager_entry(const char *manager,
 570                                        const bool is_delete)
 571 {
 572         struct tomoyo_manager e = { };
 573         struct tomoyo_acl_param param = {
 574                 .is_delete = is_delete,
 575                 .list = &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 576         };
 577         int error = is_delete ? -ENOENT : -ENOMEM;
 578         if (tomoyo_domain_def(manager)) {
 579                 if (!tomoyo_correct_domain(manager))
 580                         return -EINVAL;
 581                 e.is_domain = true;
 582         } else {
 583                 if (!tomoyo_correct_path(manager))
 584                         return -EINVAL;
 585         }
 586         e.manager = tomoyo_get_name(manager);
 587         if (e.manager) {
 588                 error = tomoyo_update_policy(&e.head, sizeof(e), &param,
 589                                              tomoyo_same_manager);
 590                 tomoyo_put_name(e.manager);
 591         }
 592         return error;
 593 }
 594
 595 /**
 596  * tomoyo_write_manager - Write manager policy.
 597  *
 598  * @head: Pointer to "struct tomoyo_io_buffer".
 599  *
 600  * Returns 0 on success, negative value otherwise.
 601  *
 602  * Caller holds tomoyo_read_lock().
 603  */
 604 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
 605 {
 606         char *data = head->write_buf;
 607         bool is_delete = tomoyo_str_starts(&data, "delete ");
 608
 609         if (!strcmp(data, "manage_by_non_root")) {
 610                 tomoyo_manage_by_non_root = !is_delete;
 611                 return 0;
 612         }
 613         return tomoyo_update_manager_entry(data, is_delete);
 614 }
 615
 616 /**
 617  * tomoyo_read_manager - Read manager policy.
 618  *
 619  * @head: Pointer to "struct tomoyo_io_buffer".
 620  *
 621  * Caller holds tomoyo_read_lock().
 622  */
 623 static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
 624 {
 625         if (head->r.eof)
 626                 return;
 627         list_for_each_cookie(head->r.acl,
 628                              &tomoyo_policy_list[TOMOYO_ID_MANAGER]) {
 629                 struct tomoyo_manager *ptr =
 630                         list_entry(head->r.acl, typeof(*ptr), head.list);
 631                 if (ptr->head.is_deleted)
 632                         continue;
 633                 if (!tomoyo_flush(head))
 634                         return;
 635                 tomoyo_set_string(head, ptr->manager->name);
 636                 tomoyo_set_lf(head);
 637         }
 638         head->r.eof = true;
 639 }
 640
 641 /**
 642  * tomoyo_manager - Check whether the current process is a policy manager.
 643  *
 644  * Returns true if the current process is permitted to modify policy
 645  * via /sys/kernel/security/tomoyo/ interface.
 646  *
 647  * Caller holds tomoyo_read_lock().
 648  */
 649 static bool tomoyo_manager(void)
 650 {
 651         struct tomoyo_manager *ptr;
 652         const char *exe;
 653         const struct task_struct *task = current;
 654         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
 655         bool found = false;
 656
 657         if (!tomoyo_policy_loaded)
 658                 return true;
 659         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
 660                 return false;
 661         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 662                                 head.list) {
 663                 if (!ptr->head.is_deleted && ptr->is_domain
 664                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
 665                         found = true;
 666                         break;
 667                 }
 668         }
 669         if (found)
 670                 return true;
 671         exe = tomoyo_get_exe();
 672         if (!exe)
 673                 return false;
 674         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
 675                                 head.list) {
 676                 if (!ptr->head.is_deleted && !ptr->is_domain
 677                     && !strcmp(exe, ptr->manager->name)) {
 678                         found = true;
 679                         break;
 680                 }
 681         }
 682         if (!found) { /* Reduce error messages. */
 683                 static pid_t last_pid;
 684                 const pid_t pid = current->pid;
 685                 if (last_pid != pid) {
 686                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
 687                                "update policies.\n", domainname->name, exe);
 688                         last_pid = pid;
 689                 }
 690         }
 691         kfree(exe);
 692         return found;
 693 }
 694
 695 /**
 696  * tomoyo_select_one - Parse select command.
 697  *
 698  * @head: Pointer to "struct tomoyo_io_buffer".
 699  * @data: String to parse.
 700  *
 701  * Returns true on success, false otherwise.
 702  *
 703  * Caller holds tomoyo_read_lock().
 704  */
 705 static bool tomoyo_select_one(struct tomoyo_io_buffer *head, const char *data)
 706 {
 707         unsigned int pid;
 708         struct tomoyo_domain_info *domain = NULL;
 709         bool global_pid = false;
 710
 711         if (!strcmp(data, "allow_execute")) {
 712                 head->r.print_execute_only = true;
 713                 return true;
 714         }
 715         if (sscanf(data, "pid=%u", &pid) == 1 ||
 716             (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
 717                 struct task_struct *p;
 718                 rcu_read_lock();
 719                 read_lock(&tasklist_lock);
 720                 if (global_pid)
 721                         p = find_task_by_pid_ns(pid, &init_pid_ns);
 722                 else
 723                         p = find_task_by_vpid(pid);
 724                 if (p)
 725                         domain = tomoyo_real_domain(p);
 726                 read_unlock(&tasklist_lock);
 727                 rcu_read_unlock();
 728         } else if (!strncmp(data, "domain=", 7)) {
 729                 if (tomoyo_domain_def(data + 7))
 730                         domain = tomoyo_find_domain(data + 7);
 731         } else
 732                 return false;
 733         head->w.domain = domain;
 734         /* Accessing read_buf is safe because head->io_sem is held. */
 735         if (!head->read_buf)
 736                 return true; /* Do nothing if open(O_WRONLY). */
 737         memset(&head->r, 0, sizeof(head->r));
 738         head->r.print_this_domain_only = true;
 739         if (domain)
 740                 head->r.domain = &domain->list;
 741         else
 742                 head->r.eof = 1;
 743         tomoyo_io_printf(head, "# select %s\n", data);
 744         if (domain && domain->is_deleted)
 745                 tomoyo_io_printf(head, "# This is a deleted domain.\n");
 746         return true;
 747 }
 748
 749 /**
 750  * tomoyo_delete_domain - Delete a domain.
 751  *
 752  * @domainname: The name of domain.
 753  *
 754  * Returns 0.
 755  *
 756  * Caller holds tomoyo_read_lock().
 757  */
 758 static int tomoyo_delete_domain(char *domainname)
 759 {
 760         struct tomoyo_domain_info *domain;
 761         struct tomoyo_path_info name;
 762
 763         name.name = domainname;
 764         tomoyo_fill_path_info(&name);
 765         if (mutex_lock_interruptible(&tomoyo_policy_lock))
 766                 return 0;
 767         /* Is there an active domain? */
 768         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 769                 /* Never delete tomoyo_kernel_domain */
 770                 if (domain == &tomoyo_kernel_domain)
 771                         continue;
 772                 if (domain->is_deleted ||
 773                     tomoyo_pathcmp(domain->domainname, &name))
 774                         continue;
 775                 domain->is_deleted = true;
 776                 break;
 777         }
 778         mutex_unlock(&tomoyo_policy_lock);
 779         return 0;
 780 }
 781
 782 /**
 783  * tomoyo_write_domain2 - Write domain policy.
 784  *
 785  * @list:      Pointer to "struct list_head".
 786  * @data:      Policy to be interpreted.
 787  * @is_delete: True if it is a delete request.
 788  *
 789  * Returns 0 on success, negative value otherwise.
 790  *
 791  * Caller holds tomoyo_read_lock().
 792  */
 793 static int tomoyo_write_domain2(struct list_head *list, char *data,
 794                                 const bool is_delete)
 795 {
 796         struct tomoyo_acl_param param = {
 797                 .list = list,
 798                 .data = data,
 799                 .is_delete = is_delete,
 800         };
 801         static const struct {
 802                 const char *keyword;
 803                 int (*write) (struct tomoyo_acl_param *);
 804         } tomoyo_callback[1] = {
 805                 { "file ", tomoyo_write_file },
 806         };
 807         u8 i;
 808         for (i = 0; i < 1; i++) {
 809                 if (!tomoyo_str_starts(&param.data,
 810                                        tomoyo_callback[i].keyword))
 811                         continue;
 812                 return tomoyo_callback[i].write(&param);
 813         }
 814         return -EINVAL;
 815 }
 816
 817 /**
 818  * tomoyo_write_domain - Write domain policy.
 819  *
 820  * @head: Pointer to "struct tomoyo_io_buffer".
 821  *
 822  * Returns 0 on success, negative value otherwise.
 823  *
 824  * Caller holds tomoyo_read_lock().
 825  */
 826 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
 827 {
 828         char *data = head->write_buf;
 829         struct tomoyo_domain_info *domain = head->w.domain;
 830         bool is_delete = false;
 831         bool is_select = false;
 832         unsigned int profile;
 833
 834         if (tomoyo_str_starts(&data, "delete "))
 835                 is_delete = true;
 836         else if (tomoyo_str_starts(&data, "select "))
 837                 is_select = true;
 838         if (is_select && tomoyo_select_one(head, data))
 839                 return 0;
 840         /* Don't allow updating policies by non manager programs. */
 841         if (!tomoyo_manager())
 842                 return -EPERM;
 843         if (tomoyo_domain_def(data)) {
 844                 domain = NULL;
 845                 if (is_delete)
 846                         tomoyo_delete_domain(data);
 847                 else if (is_select)
 848                         domain = tomoyo_find_domain(data);
 849                 else
 850                         domain = tomoyo_assign_domain(data, 0);
 851                 head->w.domain = domain;
 852                 return 0;
 853         }
 854         if (!domain)
 855                 return -EINVAL;
 856
 857         if (sscanf(data, "use_profile %u", &profile) == 1
 858             && profile < TOMOYO_MAX_PROFILES) {
 859                 if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
 860                         domain->profile = (u8) profile;
 861                 return 0;
 862         }
 863         if (!strcmp(data, "quota_exceeded")) {
 864                 domain->quota_warned = !is_delete;
 865                 return 0;
 866         }
 867         if (!strcmp(data, "transition_failed")) {
 868                 domain->transition_failed = !is_delete;
 869                 return 0;
 870         }
 871         return tomoyo_write_domain2(&domain->acl_info_list, data, is_delete);
 872 }
 873
 874 /**
 875  * tomoyo_set_group - Print category name.
 876  *
 877  * @head:     Pointer to "struct tomoyo_io_buffer".
 878  * @category: Category name.
 879  *
 880  * Returns nothing.
 881  */
 882 static void tomoyo_set_group(struct tomoyo_io_buffer *head,
 883                              const char *category)
 884 {
 885         tomoyo_set_string(head, category);
 886 }
 887
 888 /**
 889  * tomoyo_print_entry - Print an ACL entry.
 890  *
 891  * @head: Pointer to "struct tomoyo_io_buffer".
 892  * @acl:  Pointer to an ACL entry.
 893  *
 894  * Returns true on success, false otherwise.
 895  */
 896 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
 897                                struct tomoyo_acl_info *acl)
 898 {
 899         const u8 acl_type = acl->type;
 900         bool first = true;
 901         u8 bit;
 902
 903         if (acl->is_deleted)
 904                 return true;
 905         if (!tomoyo_flush(head))
 906                 return false;
 907         else if (acl_type == TOMOYO_TYPE_PATH_ACL) {
 908                 struct tomoyo_path_acl *ptr =
 909                         container_of(acl, typeof(*ptr), head);
 910                 const u16 perm = ptr->perm;
 911                 for (bit = 0; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
 912                         if (!(perm & (1 << bit)))
 913                                 continue;
 914                         if (head->r.print_execute_only &&
 915                             bit != TOMOYO_TYPE_EXECUTE)
 916                                 continue;
 917                         if (first) {
 918                                 tomoyo_set_group(head, "file ");
 919                                 first = false;
 920                         } else {
 921                                 tomoyo_set_slash(head);
 922                         }
 923                         tomoyo_set_string(head, tomoyo_path_keyword[bit]);
 924                 }
 925                 if (first)
 926                         return true;
 927                 tomoyo_print_name_union(head, &ptr->name);
 928         } else if (head->r.print_execute_only) {
 929                 return true;
 930         } else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
 931                 struct tomoyo_path2_acl *ptr =
 932                         container_of(acl, typeof(*ptr), head);
 933                 const u8 perm = ptr->perm;
 934                 for (bit = 0; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
 935                         if (!(perm & (1 << bit)))
 936                                 continue;
 937                         if (first) {
 938                                 tomoyo_set_group(head, "file ");
 939                                 first = false;
 940                         } else {
 941                                 tomoyo_set_slash(head);
 942                         }
 943                         tomoyo_set_string(head, tomoyo_mac_keywords
 944                                           [tomoyo_pp2mac[bit]]);
 945                 }
 946                 if (first)
 947                         return true;
 948                 tomoyo_print_name_union(head, &ptr->name1);
 949                 tomoyo_print_name_union(head, &ptr->name2);
 950         } else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
 951                 struct tomoyo_path_number_acl *ptr =
 952                         container_of(acl, typeof(*ptr), head);
 953                 const u8 perm = ptr->perm;
 954                 for (bit = 0; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION; bit++) {
 955                         if (!(perm & (1 << bit)))
 956                                 continue;
 957                         if (first) {
 958                                 tomoyo_set_group(head, "file ");
 959                                 first = false;
 960                         } else {
 961                                 tomoyo_set_slash(head);
 962                         }
 963                         tomoyo_set_string(head, tomoyo_mac_keywords
 964                                           [tomoyo_pn2mac[bit]]);
 965                 }
 966                 if (first)
 967                         return true;
 968                 tomoyo_print_name_union(head, &ptr->name);
 969                 tomoyo_print_number_union(head, &ptr->number);
 970         } else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
 971                 struct tomoyo_mkdev_acl *ptr =
 972                         container_of(acl, typeof(*ptr), head);
 973                 const u8 perm = ptr->perm;
 974                 for (bit = 0; bit < TOMOYO_MAX_MKDEV_OPERATION; bit++) {
 975                         if (!(perm & (1 << bit)))
 976                                 continue;
 977                         if (first) {
 978                                 tomoyo_set_group(head, "file ");
 979                                 first = false;
 980                         } else {
 981                                 tomoyo_set_slash(head);
 982                         }
 983                         tomoyo_set_string(head, tomoyo_mac_keywords
 984                                           [tomoyo_pnnn2mac[bit]]);
 985                 }
 986                 if (first)
 987                         return true;
 988                 tomoyo_print_name_union(head, &ptr->name);
 989                 tomoyo_print_number_union(head, &ptr->mode);
 990                 tomoyo_print_number_union(head, &ptr->major);
 991                 tomoyo_print_number_union(head, &ptr->minor);
 992         } else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
 993                 struct tomoyo_mount_acl *ptr =
 994                         container_of(acl, typeof(*ptr), head);
 995                 tomoyo_set_group(head, "file mount");
 996                 tomoyo_print_name_union(head, &ptr->dev_name);
 997                 tomoyo_print_name_union(head, &ptr->dir_name);
 998                 tomoyo_print_name_union(head, &ptr->fs_type);
 999                 tomoyo_print_number_union(head, &ptr->flags);
1000         }
1001         tomoyo_set_lf(head);
1002         return true;
1003 }
1004
1005 /**
1006  * tomoyo_read_domain2 - Read domain policy.
1007  *
1008  * @head:   Pointer to "struct tomoyo_io_buffer".
1009  * @domain: Pointer to "struct tomoyo_domain_info".
1010  *
1011  * Caller holds tomoyo_read_lock().
1012  *
1013  * Returns true on success, false otherwise.
1014  */
1015 static bool tomoyo_read_domain2(struct tomoyo_io_buffer *head,
1016                                 struct tomoyo_domain_info *domain)
1017 {
1018         list_for_each_cookie(head->r.acl, &domain->acl_info_list) {
1019                 struct tomoyo_acl_info *ptr =
1020                         list_entry(head->r.acl, typeof(*ptr), list);
1021                 if (!tomoyo_print_entry(head, ptr))
1022                         return false;
1023         }
1024         head->r.acl = NULL;
1025         return true;
1026 }
1027
1028 /**
1029  * tomoyo_read_domain - Read domain policy.
1030  *
1031  * @head: Pointer to "struct tomoyo_io_buffer".
1032  *
1033  * Caller holds tomoyo_read_lock().
1034  */
1035 static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
1036 {
1037         if (head->r.eof)
1038                 return;
1039         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1040                 struct tomoyo_domain_info *domain =
1041                         list_entry(head->r.domain, typeof(*domain), list);
1042                 switch (head->r.step) {
1043                 case 0:
1044                         if (domain->is_deleted &&
1045                             !head->r.print_this_domain_only)
1046                                 continue;
1047                         /* Print domainname and flags. */
1048                         tomoyo_set_string(head, domain->domainname->name);
1049                         tomoyo_set_lf(head);
1050                         tomoyo_io_printf(head, "use_profile %u\n",
1051                                          domain->profile);
1052                         if (domain->quota_warned)
1053                                 tomoyo_set_string(head, "quota_exceeded\n");
1054                         if (domain->transition_failed)
1055                                 tomoyo_set_string(head, "transition_failed\n");
1056                         head->r.step++;
1057                         tomoyo_set_lf(head);
1058                         /* fall through */
1059                 case 1:
1060                         if (!tomoyo_read_domain2(head, domain))
1061                                 return;
1062                         head->r.step++;
1063                         if (!tomoyo_set_lf(head))
1064                                 return;
1065                         /* fall through */
1066                 case 2:
1067                         head->r.step = 0;
1068                         if (head->r.print_this_domain_only)
1069                                 goto done;
1070                 }
1071         }
1072  done:
1073         head->r.eof = true;
1074 }
1075
1076 /**
1077  * tomoyo_write_domain_profile - Assign profile for specified domain.
1078  *
1079  * @head: Pointer to "struct tomoyo_io_buffer".
1080  *
1081  * Returns 0 on success, -EINVAL otherwise.
1082  *
1083  * This is equivalent to doing
1084  *
1085  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
1086  *     /usr/sbin/tomoyo-loadpolicy -d
1087  *
1088  * Caller holds tomoyo_read_lock().
1089  */
1090 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
1091 {
1092         char *data = head->write_buf;
1093         char *cp = strchr(data, ' ');
1094         struct tomoyo_domain_info *domain;
1095         unsigned long profile;
1096
1097         if (!cp)
1098                 return -EINVAL;
1099         *cp = '\0';
1100         domain = tomoyo_find_domain(cp + 1);
1101         if (strict_strtoul(data, 10, &profile))
1102                 return -EINVAL;
1103         if (domain && profile < TOMOYO_MAX_PROFILES
1104             && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
1105                 domain->profile = (u8) profile;
1106         return 0;
1107 }
1108
1109 /**
1110  * tomoyo_read_domain_profile - Read only domainname and profile.
1111  *
1112  * @head: Pointer to "struct tomoyo_io_buffer".
1113  *
1114  * Returns list of profile number and domainname pairs.
1115  *
1116  * This is equivalent to doing
1117  *
1118  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
1119  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
1120  *     domainname = $0; } else if ( $1 == "use_profile" ) {
1121  *     print $2 " " domainname; domainname = ""; } } ; '
1122  *
1123  * Caller holds tomoyo_read_lock().
1124  */
1125 static void tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
1126 {
1127         if (head->r.eof)
1128                 return;
1129         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1130                 struct tomoyo_domain_info *domain =
1131                         list_entry(head->r.domain, typeof(*domain), list);
1132                 if (domain->is_deleted)
1133                         continue;
1134                 if (!tomoyo_flush(head))
1135                         return;
1136                 tomoyo_io_printf(head, "%u ", domain->profile);
1137                 tomoyo_set_string(head, domain->domainname->name);
1138                 tomoyo_set_lf(head);
1139         }
1140         head->r.eof = true;
1141 }
1142
1143 /**
1144  * tomoyo_write_pid: Specify PID to obtain domainname.
1145  *
1146  * @head: Pointer to "struct tomoyo_io_buffer".
1147  *
1148  * Returns 0.
1149  */
1150 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1151 {
1152         head->r.eof = false;
1153         return 0;
1154 }
1155
1156 /**
1157  * tomoyo_read_pid - Get domainname of the specified PID.
1158  *
1159  * @head: Pointer to "struct tomoyo_io_buffer".
1160  *
1161  * Returns the domainname which the specified PID is in on success,
1162  * empty string otherwise.
1163  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1164  * using read()/write() interface rather than sysctl() interface.
1165  */
1166 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1167 {
1168         char *buf = head->write_buf;
1169         bool global_pid = false;
1170         unsigned int pid;
1171         struct task_struct *p;
1172         struct tomoyo_domain_info *domain = NULL;
1173
1174         /* Accessing write_buf is safe because head->io_sem is held. */
1175         if (!buf) {
1176                 head->r.eof = true;
1177                 return; /* Do nothing if open(O_RDONLY). */
1178         }
1179         if (head->r.w_pos || head->r.eof)
1180                 return;
1181         head->r.eof = true;
1182         if (tomoyo_str_starts(&buf, "global-pid "))
1183                 global_pid = true;
1184         pid = (unsigned int) simple_strtoul(buf, NULL, 10);
1185         rcu_read_lock();
1186         read_lock(&tasklist_lock);
1187         if (global_pid)
1188                 p = find_task_by_pid_ns(pid, &init_pid_ns);
1189         else
1190                 p = find_task_by_vpid(pid);
1191         if (p)
1192                 domain = tomoyo_real_domain(p);
1193         read_unlock(&tasklist_lock);
1194         rcu_read_unlock();
1195         if (!domain)
1196                 return;
1197         tomoyo_io_printf(head, "%u %u ", pid, domain->profile);
1198         tomoyo_set_string(head, domain->domainname->name);
1199 }
1200
1201 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1202         [TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain",
1203         [TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain",
1204         [TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain",
1205         [TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain",
1206 };
1207
1208 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1209         [TOMOYO_PATH_GROUP]   = "path_group ",
1210         [TOMOYO_NUMBER_GROUP] = "number_group ",
1211 };
1212
1213 /**
1214  * tomoyo_write_exception - Write exception policy.
1215  *
1216  * @head: Pointer to "struct tomoyo_io_buffer".
1217  *
1218  * Returns 0 on success, negative value otherwise.
1219  *
1220  * Caller holds tomoyo_read_lock().
1221  */
1222 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
1223 {
1224         struct tomoyo_acl_param param = {
1225                 .data = head->write_buf,
1226         };
1227         u8 i;
1228         param.is_delete = tomoyo_str_starts(&param.data, "delete ");
1229         if (tomoyo_str_starts(&param.data, "aggregator "))
1230                 return tomoyo_write_aggregator(&param);
1231         for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
1232                 if (tomoyo_str_starts(&param.data, tomoyo_transition_type[i]))
1233                         return tomoyo_write_transition_control(&param, i);
1234         for (i = 0; i < TOMOYO_MAX_GROUP; i++)
1235                 if (tomoyo_str_starts(&param.data, tomoyo_group_name[i]))
1236                         return tomoyo_write_group(&param, i);
1237         return -EINVAL;
1238 }
1239
1240 /**
1241  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
1242  *
1243  * @head: Pointer to "struct tomoyo_io_buffer".
1244  * @idx:  Index number.
1245  *
1246  * Returns true on success, false otherwise.
1247  *
1248  * Caller holds tomoyo_read_lock().
1249  */
1250 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1251 {
1252         list_for_each_cookie(head->r.group, &tomoyo_group_list[idx]) {
1253                 struct tomoyo_group *group =
1254                         list_entry(head->r.group, typeof(*group), head.list);
1255                 list_for_each_cookie(head->r.acl, &group->member_list) {
1256                         struct tomoyo_acl_head *ptr =
1257                                 list_entry(head->r.acl, typeof(*ptr), list);
1258                         if (ptr->is_deleted)
1259                                 continue;
1260                         if (!tomoyo_flush(head))
1261                                 return false;
1262                         tomoyo_set_string(head, tomoyo_group_name[idx]);
1263                         tomoyo_set_string(head, group->group_name->name);
1264                         if (idx == TOMOYO_PATH_GROUP) {
1265                                 tomoyo_set_space(head);
1266                                 tomoyo_set_string(head, container_of
1267                                                (ptr, struct tomoyo_path_group,
1268                                                 head)->member_name->name);
1269                         } else if (idx == TOMOYO_NUMBER_GROUP) {
1270                                 tomoyo_print_number_union(head, &container_of
1271                                                           (ptr,
1272                                                    struct tomoyo_number_group,
1273                                                            head)->number);
1274                         }
1275                         tomoyo_set_lf(head);
1276                 }
1277                 head->r.acl = NULL;
1278         }
1279         head->r.group = NULL;
1280         return true;
1281 }
1282
1283 /**
1284  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1285  *
1286  * @head: Pointer to "struct tomoyo_io_buffer".
1287  * @idx:  Index number.
1288  *
1289  * Returns true on success, false otherwise.
1290  *
1291  * Caller holds tomoyo_read_lock().
1292  */
1293 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1294 {
1295         list_for_each_cookie(head->r.acl, &tomoyo_policy_list[idx]) {
1296                 struct tomoyo_acl_head *acl =
1297                         container_of(head->r.acl, typeof(*acl), list);
1298                 if (acl->is_deleted)
1299                         continue;
1300                 if (!tomoyo_flush(head))
1301                         return false;
1302                 switch (idx) {
1303                 case TOMOYO_ID_TRANSITION_CONTROL:
1304                         {
1305                                 struct tomoyo_transition_control *ptr =
1306                                         container_of(acl, typeof(*ptr), head);
1307                                 tomoyo_set_string(head, tomoyo_transition_type
1308                                                   [ptr->type]);
1309                                 tomoyo_set_string(head, ptr->program ?
1310                                                   ptr->program->name : "any");
1311                                 tomoyo_set_string(head, " from ");
1312                                 tomoyo_set_string(head, ptr->domainname ?
1313                                                   ptr->domainname->name :
1314                                                   "any");
1315                         }
1316                         break;
1317                 case TOMOYO_ID_AGGREGATOR:
1318                         {
1319                                 struct tomoyo_aggregator *ptr =
1320                                         container_of(acl, typeof(*ptr), head);
1321                                 tomoyo_set_string(head, "aggregator ");
1322                                 tomoyo_set_string(head,
1323                                                   ptr->original_name->name);
1324                                 tomoyo_set_space(head);
1325                                 tomoyo_set_string(head,
1326                                                ptr->aggregated_name->name);
1327                         }
1328                         break;
1329                 default:
1330                         continue;
1331                 }
1332                 tomoyo_set_lf(head);
1333         }
1334         head->r.acl = NULL;
1335         return true;
1336 }
1337
1338 /**
1339  * tomoyo_read_exception - Read exception policy.
1340  *
1341  * @head: Pointer to "struct tomoyo_io_buffer".
1342  *
1343  * Caller holds tomoyo_read_lock().
1344  */
1345 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
1346 {
1347         if (head->r.eof)
1348                 return;
1349         while (head->r.step < TOMOYO_MAX_POLICY &&
1350                tomoyo_read_policy(head, head->r.step))
1351                 head->r.step++;
1352         if (head->r.step < TOMOYO_MAX_POLICY)
1353                 return;
1354         while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1355                tomoyo_read_group(head, head->r.step - TOMOYO_MAX_POLICY))
1356                 head->r.step++;
1357         if (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1358                 return;
1359         head->r.eof = true;
1360 }
1361
1362 /**
1363  * tomoyo_print_header - Get header line of audit log.
1364  *
1365  * @r: Pointer to "struct tomoyo_request_info".
1366  *
1367  * Returns string representation.
1368  *
1369  * This function uses kmalloc(), so caller must kfree() if this function
1370  * didn't return NULL.
1371  */
1372 static char *tomoyo_print_header(struct tomoyo_request_info *r)
1373 {
1374         struct timeval tv;
1375         const pid_t gpid = task_pid_nr(current);
1376         static const int tomoyo_buffer_len = 4096;
1377         char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
1378         pid_t ppid;
1379         if (!buffer)
1380                 return NULL;
1381         do_gettimeofday(&tv);
1382         rcu_read_lock();
1383         ppid = task_tgid_vnr(current->real_parent);
1384         rcu_read_unlock();
1385         snprintf(buffer, tomoyo_buffer_len - 1,
1386                  "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
1387                  " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
1388                  " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
1389                  tv.tv_sec, r->profile, tomoyo_mode[r->mode], gpid,
1390                  task_tgid_vnr(current), ppid,
1391                  current_uid(), current_gid(), current_euid(),
1392                  current_egid(), current_suid(), current_sgid(),
1393                  current_fsuid(), current_fsgid());
1394         return buffer;
1395 }
1396
1397 /**
1398  * tomoyo_init_audit_log - Allocate buffer for audit logs.
1399  *
1400  * @len: Required size.
1401  * @r:   Pointer to "struct tomoyo_request_info".
1402  *
1403  * Returns pointer to allocated memory.
1404  *
1405  * The @len is updated to add the header lines' size on success.
1406  *
1407  * This function uses kzalloc(), so caller must kfree() if this function
1408  * didn't return NULL.
1409  */
1410 static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r)
1411 {
1412         char *buf = NULL;
1413         const char *header;
1414         const char *domainname;
1415         if (!r->domain)
1416                 r->domain = tomoyo_domain();
1417         domainname = r->domain->domainname->name;
1418         header = tomoyo_print_header(r);
1419         if (!header)
1420                 return NULL;
1421         *len += strlen(domainname) + strlen(header) + 10;
1422         buf = kzalloc(*len, GFP_NOFS);
1423         if (buf)
1424                 snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname);
1425         kfree(header);
1426         return buf;
1427 }
1428
1429 /* Wait queue for tomoyo_query_list. */
1430 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1431
1432 /* Lock for manipulating tomoyo_query_list. */
1433 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1434
1435 /* Structure for query. */
1436 struct tomoyo_query {
1437         struct list_head list;
1438         char *query;
1439         int query_len;
1440         unsigned int serial;
1441         int timer;
1442         int answer;
1443 };
1444
1445 /* The list for "struct tomoyo_query". */
1446 static LIST_HEAD(tomoyo_query_list);
1447
1448 /*
1449  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1450  * interface.
1451  */
1452 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1453
1454 /**
1455  * tomoyo_supervisor - Ask for the supervisor's decision.
1456  *
1457  * @r:       Pointer to "struct tomoyo_request_info".
1458  * @fmt:     The printf()'s format string, followed by parameters.
1459  *
1460  * Returns 0 if the supervisor decided to permit the access request which
1461  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1462  * supervisor decided to retry the access request which violated the policy in
1463  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1464  */
1465 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1466 {
1467         va_list args;
1468         int error = -EPERM;
1469         int pos;
1470         int len;
1471         static unsigned int tomoyo_serial;
1472         struct tomoyo_query *entry = NULL;
1473         bool quota_exceeded = false;
1474         char *header;
1475         switch (r->mode) {
1476                 char *buffer;
1477         case TOMOYO_CONFIG_LEARNING:
1478                 if (!tomoyo_domain_quota_is_ok(r))
1479                         return 0;
1480                 va_start(args, fmt);
1481                 len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4;
1482                 va_end(args);
1483                 buffer = kmalloc(len, GFP_NOFS);
1484                 if (!buffer)
1485                         return 0;
1486                 va_start(args, fmt);
1487                 vsnprintf(buffer, len - 1, fmt, args);
1488                 va_end(args);
1489                 tomoyo_normalize_line(buffer);
1490                 tomoyo_write_domain2(&r->domain->acl_info_list, buffer, false);
1491                 kfree(buffer);
1492                 /* fall through */
1493         case TOMOYO_CONFIG_PERMISSIVE:
1494                 return 0;
1495         }
1496         if (!r->domain)
1497                 r->domain = tomoyo_domain();
1498         if (!atomic_read(&tomoyo_query_observers))
1499                 return -EPERM;
1500         va_start(args, fmt);
1501         len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
1502         va_end(args);
1503         header = tomoyo_init_audit_log(&len, r);
1504         if (!header)
1505                 goto out;
1506         entry = kzalloc(sizeof(*entry), GFP_NOFS);
1507         if (!entry)
1508                 goto out;
1509         entry->query = kzalloc(len, GFP_NOFS);
1510         if (!entry->query)
1511                 goto out;
1512         len = ksize(entry->query);
1513         spin_lock(&tomoyo_query_list_lock);
1514         if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
1515             sizeof(*entry) >= tomoyo_quota_for_query) {
1516                 quota_exceeded = true;
1517         } else {
1518                 tomoyo_query_memory_size += len + sizeof(*entry);
1519                 entry->serial = tomoyo_serial++;
1520         }
1521         spin_unlock(&tomoyo_query_list_lock);
1522         if (quota_exceeded)
1523                 goto out;
1524         pos = snprintf(entry->query, len - 1, "Q%u-%hu\n%s",
1525                        entry->serial, r->retry, header);
1526         kfree(header);
1527         header = NULL;
1528         va_start(args, fmt);
1529         vsnprintf(entry->query + pos, len - 1 - pos, fmt, args);
1530         entry->query_len = strlen(entry->query) + 1;
1531         va_end(args);
1532         spin_lock(&tomoyo_query_list_lock);
1533         list_add_tail(&entry->list, &tomoyo_query_list);
1534         spin_unlock(&tomoyo_query_list_lock);
1535         /* Give 10 seconds for supervisor's opinion. */
1536         for (entry->timer = 0;
1537              atomic_read(&tomoyo_query_observers) && entry->timer < 100;
1538              entry->timer++) {
1539                 wake_up(&tomoyo_query_wait);
1540                 set_current_state(TASK_INTERRUPTIBLE);
1541                 schedule_timeout(HZ / 10);
1542                 if (entry->answer)
1543                         break;
1544         }
1545         spin_lock(&tomoyo_query_list_lock);
1546         list_del(&entry->list);
1547         tomoyo_query_memory_size -= len + sizeof(*entry);
1548         spin_unlock(&tomoyo_query_list_lock);
1549         switch (entry->answer) {
1550         case 3: /* Asked to retry by administrator. */
1551                 error = TOMOYO_RETRY_REQUEST;
1552                 r->retry++;
1553                 break;
1554         case 1:
1555                 /* Granted by administrator. */
1556                 error = 0;
1557                 break;
1558         case 0:
1559                 /* Timed out. */
1560                 break;
1561         default:
1562                 /* Rejected by administrator. */
1563                 break;
1564         }
1565  out:
1566         if (entry)
1567                 kfree(entry->query);
1568         kfree(entry);
1569         kfree(header);
1570         return error;
1571 }
1572
1573 /**
1574  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1575  *
1576  * @file: Pointer to "struct file".
1577  * @wait: Pointer to "poll_table".
1578  *
1579  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1580  *
1581  * Waits for access requests which violated policy in enforcing mode.
1582  */
1583 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1584 {
1585         struct list_head *tmp;
1586         bool found = false;
1587         u8 i;
1588         for (i = 0; i < 2; i++) {
1589                 spin_lock(&tomoyo_query_list_lock);
1590                 list_for_each(tmp, &tomoyo_query_list) {
1591                         struct tomoyo_query *ptr =
1592                                 list_entry(tmp, typeof(*ptr), list);
1593                         if (ptr->answer)
1594                                 continue;
1595                         found = true;
1596                         break;
1597                 }
1598                 spin_unlock(&tomoyo_query_list_lock);
1599                 if (found)
1600                         return POLLIN | POLLRDNORM;
1601                 if (i)
1602                         break;
1603                 poll_wait(file, &tomoyo_query_wait, wait);
1604         }
1605         return 0;
1606 }
1607
1608 /**
1609  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1610  *
1611  * @head: Pointer to "struct tomoyo_io_buffer".
1612  */
1613 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1614 {
1615         struct list_head *tmp;
1616         int pos = 0;
1617         int len = 0;
1618         char *buf;
1619         if (head->r.w_pos)
1620                 return;
1621         if (head->read_buf) {
1622                 kfree(head->read_buf);
1623                 head->read_buf = NULL;
1624         }
1625         spin_lock(&tomoyo_query_list_lock);
1626         list_for_each(tmp, &tomoyo_query_list) {
1627                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1628                 if (ptr->answer)
1629                         continue;
1630                 if (pos++ != head->r.query_index)
1631                         continue;
1632                 len = ptr->query_len;
1633                 break;
1634         }
1635         spin_unlock(&tomoyo_query_list_lock);
1636         if (!len) {
1637                 head->r.query_index = 0;
1638                 return;
1639         }
1640         buf = kzalloc(len, GFP_NOFS);
1641         if (!buf)
1642                 return;
1643         pos = 0;
1644         spin_lock(&tomoyo_query_list_lock);
1645         list_for_each(tmp, &tomoyo_query_list) {
1646                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1647                 if (ptr->answer)
1648                         continue;
1649                 if (pos++ != head->r.query_index)
1650                         continue;
1651                 /*
1652                  * Some query can be skipped because tomoyo_query_list
1653                  * can change, but I don't care.
1654                  */
1655                 if (len == ptr->query_len)
1656                         memmove(buf, ptr->query, len);
1657                 break;
1658         }
1659         spin_unlock(&tomoyo_query_list_lock);
1660         if (buf[0]) {
1661                 head->read_buf = buf;
1662                 head->r.w[head->r.w_pos++] = buf;
1663                 head->r.query_index++;
1664         } else {
1665                 kfree(buf);
1666         }
1667 }
1668
1669 /**
1670  * tomoyo_write_answer - Write the supervisor's decision.
1671  *
1672  * @head: Pointer to "struct tomoyo_io_buffer".
1673  *
1674  * Returns 0 on success, -EINVAL otherwise.
1675  */
1676 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1677 {
1678         char *data = head->write_buf;
1679         struct list_head *tmp;
1680         unsigned int serial;
1681         unsigned int answer;
1682         spin_lock(&tomoyo_query_list_lock);
1683         list_for_each(tmp, &tomoyo_query_list) {
1684                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1685                 ptr->timer = 0;
1686         }
1687         spin_unlock(&tomoyo_query_list_lock);
1688         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1689                 return -EINVAL;
1690         spin_lock(&tomoyo_query_list_lock);
1691         list_for_each(tmp, &tomoyo_query_list) {
1692                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1693                 if (ptr->serial != serial)
1694                         continue;
1695                 if (!ptr->answer)
1696                         ptr->answer = answer;
1697                 break;
1698         }
1699         spin_unlock(&tomoyo_query_list_lock);
1700         return 0;
1701 }
1702
1703 /**
1704  * tomoyo_read_version: Get version.
1705  *
1706  * @head: Pointer to "struct tomoyo_io_buffer".
1707  *
1708  * Returns version information.
1709  */
1710 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
1711 {
1712         if (!head->r.eof) {
1713                 tomoyo_io_printf(head, "2.4.0");
1714                 head->r.eof = true;
1715         }
1716 }
1717
1718 /**
1719  * tomoyo_read_self_domain - Get the current process's domainname.
1720  *
1721  * @head: Pointer to "struct tomoyo_io_buffer".
1722  *
1723  * Returns the current process's domainname.
1724  */
1725 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1726 {
1727         if (!head->r.eof) {
1728                 /*
1729                  * tomoyo_domain()->domainname != NULL
1730                  * because every process belongs to a domain and
1731                  * the domain's name cannot be NULL.
1732                  */
1733                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1734                 head->r.eof = true;
1735         }
1736 }
1737
1738 /**
1739  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1740  *
1741  * @type: Type of interface.
1742  * @file: Pointer to "struct file".
1743  *
1744  * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
1745  *
1746  * Caller acquires tomoyo_read_lock().
1747  */
1748 int tomoyo_open_control(const u8 type, struct file *file)
1749 {
1750         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1751
1752         if (!head)
1753                 return -ENOMEM;
1754         mutex_init(&head->io_sem);
1755         head->type = type;
1756         switch (type) {
1757         case TOMOYO_DOMAINPOLICY:
1758                 /* /sys/kernel/security/tomoyo/domain_policy */
1759                 head->write = tomoyo_write_domain;
1760                 head->read = tomoyo_read_domain;
1761                 break;
1762         case TOMOYO_EXCEPTIONPOLICY:
1763                 /* /sys/kernel/security/tomoyo/exception_policy */
1764                 head->write = tomoyo_write_exception;
1765                 head->read = tomoyo_read_exception;
1766                 break;
1767         case TOMOYO_SELFDOMAIN:
1768                 /* /sys/kernel/security/tomoyo/self_domain */
1769                 head->read = tomoyo_read_self_domain;
1770                 break;
1771         case TOMOYO_DOMAIN_STATUS:
1772                 /* /sys/kernel/security/tomoyo/.domain_status */
1773                 head->write = tomoyo_write_domain_profile;
1774                 head->read = tomoyo_read_domain_profile;
1775                 break;
1776         case TOMOYO_PROCESS_STATUS:
1777                 /* /sys/kernel/security/tomoyo/.process_status */
1778                 head->write = tomoyo_write_pid;
1779                 head->read = tomoyo_read_pid;
1780                 break;
1781         case TOMOYO_VERSION:
1782                 /* /sys/kernel/security/tomoyo/version */
1783                 head->read = tomoyo_read_version;
1784                 head->readbuf_size = 128;
1785                 break;
1786         case TOMOYO_MEMINFO:
1787                 /* /sys/kernel/security/tomoyo/meminfo */
1788                 head->write = tomoyo_write_memory_quota;
1789                 head->read = tomoyo_read_memory_counter;
1790                 head->readbuf_size = 512;
1791                 break;
1792         case TOMOYO_PROFILE:
1793                 /* /sys/kernel/security/tomoyo/profile */
1794                 head->write = tomoyo_write_profile;
1795                 head->read = tomoyo_read_profile;
1796                 break;
1797         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1798                 head->poll = tomoyo_poll_query;
1799                 head->write = tomoyo_write_answer;
1800                 head->read = tomoyo_read_query;
1801                 break;
1802         case TOMOYO_MANAGER:
1803                 /* /sys/kernel/security/tomoyo/manager */
1804                 head->write = tomoyo_write_manager;
1805                 head->read = tomoyo_read_manager;
1806                 break;
1807         }
1808         if (!(file->f_mode & FMODE_READ)) {
1809                 /*
1810                  * No need to allocate read_buf since it is not opened
1811                  * for reading.
1812                  */
1813                 head->read = NULL;
1814                 head->poll = NULL;
1815         } else if (!head->poll) {
1816                 /* Don't allocate read_buf for poll() access. */
1817                 if (!head->readbuf_size)
1818                         head->readbuf_size = 4096 * 2;
1819                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1820                 if (!head->read_buf) {
1821                         kfree(head);
1822                         return -ENOMEM;
1823                 }
1824         }
1825         if (!(file->f_mode & FMODE_WRITE)) {
1826                 /*
1827                  * No need to allocate write_buf since it is not opened
1828                  * for writing.
1829                  */
1830                 head->write = NULL;
1831         } else if (head->write) {
1832                 head->writebuf_size = 4096 * 2;
1833                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1834                 if (!head->write_buf) {
1835                         kfree(head->read_buf);
1836                         kfree(head);
1837                         return -ENOMEM;
1838                 }
1839         }
1840         if (type != TOMOYO_QUERY)
1841                 head->reader_idx = tomoyo_read_lock();
1842         file->private_data = head;
1843         /*
1844          * If the file is /sys/kernel/security/tomoyo/query , increment the
1845          * observer counter.
1846          * The obserber counter is used by tomoyo_supervisor() to see if
1847          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1848          */
1849         if (type == TOMOYO_QUERY)
1850                 atomic_inc(&tomoyo_query_observers);
1851         return 0;
1852 }
1853
1854 /**
1855  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1856  *
1857  * @file: Pointer to "struct file".
1858  * @wait: Pointer to "poll_table".
1859  *
1860  * Waits for read readiness.
1861  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
1862  */
1863 int tomoyo_poll_control(struct file *file, poll_table *wait)
1864 {
1865         struct tomoyo_io_buffer *head = file->private_data;
1866         if (!head->poll)
1867                 return -ENOSYS;
1868         return head->poll(file, wait);
1869 }
1870
1871 /**
1872  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
1873  *
1874  * @head:       Pointer to "struct tomoyo_io_buffer".
1875  * @buffer:     Poiner to buffer to write to.
1876  * @buffer_len: Size of @buffer.
1877  *
1878  * Returns bytes read on success, negative value otherwise.
1879  *
1880  * Caller holds tomoyo_read_lock().
1881  */
1882 int tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
1883                         const int buffer_len)
1884 {
1885         int len;
1886
1887         if (!head->read)
1888                 return -ENOSYS;
1889         if (mutex_lock_interruptible(&head->io_sem))
1890                 return -EINTR;
1891         head->read_user_buf = buffer;
1892         head->read_user_buf_avail = buffer_len;
1893         if (tomoyo_flush(head))
1894                 /* Call the policy handler. */
1895                 head->read(head);
1896         tomoyo_flush(head);
1897         len = head->read_user_buf - buffer;
1898         mutex_unlock(&head->io_sem);
1899         return len;
1900 }
1901
1902 /**
1903  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
1904  *
1905  * @head:       Pointer to "struct tomoyo_io_buffer".
1906  * @buffer:     Pointer to buffer to read from.
1907  * @buffer_len: Size of @buffer.
1908  *
1909  * Returns @buffer_len on success, negative value otherwise.
1910  *
1911  * Caller holds tomoyo_read_lock().
1912  */
1913 int tomoyo_write_control(struct tomoyo_io_buffer *head,
1914                          const char __user *buffer, const int buffer_len)
1915 {
1916         int error = buffer_len;
1917         int avail_len = buffer_len;
1918         char *cp0 = head->write_buf;
1919
1920         if (!head->write)
1921                 return -ENOSYS;
1922         if (!access_ok(VERIFY_READ, buffer, buffer_len))
1923                 return -EFAULT;
1924         /* Don't allow updating policies by non manager programs. */
1925         if (head->write != tomoyo_write_pid &&
1926             head->write != tomoyo_write_domain && !tomoyo_manager())
1927                 return -EPERM;
1928         if (mutex_lock_interruptible(&head->io_sem))
1929                 return -EINTR;
1930         /* Read a line and dispatch it to the policy handler. */
1931         while (avail_len > 0) {
1932                 char c;
1933                 if (head->w.avail >= head->writebuf_size - 1) {
1934                         error = -ENOMEM;
1935                         break;
1936                 } else if (get_user(c, buffer)) {
1937                         error = -EFAULT;
1938                         break;
1939                 }
1940                 buffer++;
1941                 avail_len--;
1942                 cp0[head->w.avail++] = c;
1943                 if (c != '\n')
1944                         continue;
1945                 cp0[head->w.avail - 1] = '\0';
1946                 head->w.avail = 0;
1947                 tomoyo_normalize_line(cp0);
1948                 head->write(head);
1949         }
1950         mutex_unlock(&head->io_sem);
1951         return error;
1952 }
1953
1954 /**
1955  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
1956  *
1957  * @head: Pointer to "struct tomoyo_io_buffer".
1958  *
1959  * Releases memory and returns 0.
1960  *
1961  * Caller looses tomoyo_read_lock().
1962  */
1963 int tomoyo_close_control(struct tomoyo_io_buffer *head)
1964 {
1965         const bool is_write = !!head->write_buf;
1966
1967         /*
1968          * If the file is /sys/kernel/security/tomoyo/query , decrement the
1969          * observer counter.
1970          */
1971         if (head->type == TOMOYO_QUERY)
1972                 atomic_dec(&tomoyo_query_observers);
1973         else
1974                 tomoyo_read_unlock(head->reader_idx);
1975         /* Release memory used for policy I/O. */
1976         kfree(head->read_buf);
1977         head->read_buf = NULL;
1978         kfree(head->write_buf);
1979         head->write_buf = NULL;
1980         kfree(head);
1981         if (is_write)
1982                 tomoyo_run_gc();
1983         return 0;
1984 }
1985
1986 /**
1987  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
1988  */
1989 void tomoyo_check_profile(void)
1990 {
1991         struct tomoyo_domain_info *domain;
1992         const int idx = tomoyo_read_lock();
1993         tomoyo_policy_loaded = true;
1994         /* Check all profiles currently assigned to domains are defined. */
1995         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
1996                 const u8 profile = domain->profile;
1997                 if (tomoyo_profile_ptr[profile])
1998                         continue;
1999                 printk(KERN_ERR "You need to define profile %u before using it.\n",
2000                        profile);
2001                 printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.3/ "
2002                        "for more information.\n");
2003                 panic("Profile %u (used by '%s') not defined.\n",
2004                       profile, domain->domainname->name);
2005         }
2006         tomoyo_read_unlock(idx);
2007         if (tomoyo_profile_version != 20090903) {
2008                 printk(KERN_ERR "You need to install userland programs for "
2009                        "TOMOYO 2.3 and initialize policy configuration.\n");
2010                 printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.3/ "
2011                        "for more information.\n");
2012                 panic("Profile version %u is not supported.\n",
2013                       tomoyo_profile_version);
2014         }
2015         printk(KERN_INFO "TOMOYO: 2.3.0\n");
2016         printk(KERN_INFO "Mandatory Access Control activated.\n");
2017 }