1 /* auditsc.c -- System-call auditing support 2 * Handles all system-call specific auditing features. 3 * 4 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. 5 * Copyright 2005 Hewlett-Packard Development Company, L.P. 6 * Copyright (C) 2005, 2006 IBM Corporation 7 * All Rights Reserved. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 22 * 23 * Written by Rickard E. (Rik) Faith <faith@redhat.com> 24 * 25 * Many of the ideas implemented here are from Stephen C. Tweedie, 26 * especially the idea of avoiding a copy by using getname. 27 * 28 * The method for actual interception of syscall entry and exit (not in 29 * this file -- see entry.S) is based on a GPL'd patch written by 30 * okir@suse.de and Copyright 2003 SuSE Linux AG. 31 * 32 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>, 33 * 2006. 34 * 35 * The support of additional filter rules compares (>, <, >=, <=) was 36 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. 37 * 38 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional 39 * filesystem information. 40 * 41 * Subject and object context labeling support added by <danjones@us.ibm.com> 42 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance. 43 */ 44 45 #include <linux/init.h> 46 #include <asm/types.h> 47 #include <asm/atomic.h> 48 #include <asm/types.h> 49 #include <linux/fs.h> 50 #include <linux/namei.h> 51 #include <linux/mm.h> 52 #include <linux/module.h> 53 #include <linux/mount.h> 54 #include <linux/socket.h> 55 #include <linux/mqueue.h> 56 #include <linux/audit.h> 57 #include <linux/personality.h> 58 #include <linux/time.h> 59 #include <linux/netlink.h> 60 #include <linux/compiler.h> 61 #include <asm/unistd.h> 62 #include <linux/security.h> 63 #include <linux/list.h> 64 #include <linux/tty.h> 65 #include <linux/selinux.h> 66 #include <linux/binfmts.h> 67 #include <linux/highmem.h> 68 #include <linux/syscalls.h> 69 70 #include "audit.h" 71 72 extern struct list_head audit_filter_list[]; 73 74 /* No syscall auditing will take place unless audit_enabled != 0. */ 75 extern int audit_enabled; 76 77 /* AUDIT_NAMES is the number of slots we reserve in the audit_context 78 * for saving names from getname(). */ 79 #define AUDIT_NAMES 20 80 81 /* Indicates that audit should log the full pathname. */ 82 #define AUDIT_NAME_FULL -1 83 84 /* number of audit rules */ 85 int audit_n_rules; 86 87 /* determines whether we collect data for signals sent */ 88 int audit_signals; 89 90 /* When fs/namei.c:getname() is called, we store the pointer in name and 91 * we don't let putname() free it (instead we free all of the saved 92 * pointers at syscall exit time). 93 * 94 * Further, in fs/namei.c:path_lookup() we store the inode and device. */ 95 struct audit_names { 96 const char *name; 97 int name_len; /* number of name's characters to log */ 98 unsigned name_put; /* call __putname() for this name */ 99 unsigned long ino; 100 dev_t dev; 101 umode_t mode; 102 uid_t uid; 103 gid_t gid; 104 dev_t rdev; 105 u32 osid; 106 }; 107 108 struct audit_aux_data { 109 struct audit_aux_data *next; 110 int type; 111 }; 112 113 #define AUDIT_AUX_IPCPERM 0 114 115 /* Number of target pids per aux struct. */ 116 #define AUDIT_AUX_PIDS 16 117 118 struct audit_aux_data_mq_open { 119 struct audit_aux_data d; 120 int oflag; 121 mode_t mode; 122 struct mq_attr attr; 123 }; 124 125 struct audit_aux_data_mq_sendrecv { 126 struct audit_aux_data d; 127 mqd_t mqdes; 128 size_t msg_len; 129 unsigned int msg_prio; 130 struct timespec abs_timeout; 131 }; 132 133 struct audit_aux_data_mq_notify { 134 struct audit_aux_data d; 135 mqd_t mqdes; 136 struct sigevent notification; 137 }; 138 139 struct audit_aux_data_mq_getsetattr { 140 struct audit_aux_data d; 141 mqd_t mqdes; 142 struct mq_attr mqstat; 143 }; 144 145 struct audit_aux_data_ipcctl { 146 struct audit_aux_data d; 147 struct ipc_perm p; 148 unsigned long qbytes; 149 uid_t uid; 150 gid_t gid; 151 mode_t mode; 152 u32 osid; 153 }; 154 155 struct audit_aux_data_execve { 156 struct audit_aux_data d; 157 int argc; 158 int envc; 159 char mem[0]; 160 }; 161 162 struct audit_aux_data_socketcall { 163 struct audit_aux_data d; 164 int nargs; 165 unsigned long args[0]; 166 }; 167 168 struct audit_aux_data_sockaddr { 169 struct audit_aux_data d; 170 int len; 171 char a[0]; 172 }; 173 174 struct audit_aux_data_fd_pair { 175 struct audit_aux_data d; 176 int fd[2]; 177 }; 178 179 struct audit_aux_data_path { 180 struct audit_aux_data d; 181 struct dentry *dentry; 182 struct vfsmount *mnt; 183 }; 184 185 struct audit_aux_data_pids { 186 struct audit_aux_data d; 187 pid_t target_pid[AUDIT_AUX_PIDS]; 188 u32 target_sid[AUDIT_AUX_PIDS]; 189 int pid_count; 190 }; 191 192 /* The per-task audit context. */ 193 struct audit_context { 194 int dummy; /* must be the first element */ 195 int in_syscall; /* 1 if task is in a syscall */ 196 enum audit_state state; 197 unsigned int serial; /* serial number for record */ 198 struct timespec ctime; /* time of syscall entry */ 199 uid_t loginuid; /* login uid (identity) */ 200 int major; /* syscall number */ 201 unsigned long argv[4]; /* syscall arguments */ 202 int return_valid; /* return code is valid */ 203 long return_code;/* syscall return code */ 204 int auditable; /* 1 if record should be written */ 205 int name_count; 206 struct audit_names names[AUDIT_NAMES]; 207 char * filterkey; /* key for rule that triggered record */ 208 struct dentry * pwd; 209 struct vfsmount * pwdmnt; 210 struct audit_context *previous; /* For nested syscalls */ 211 struct audit_aux_data *aux; 212 struct audit_aux_data *aux_pids; 213 214 /* Save things to print about task_struct */ 215 pid_t pid, ppid; 216 uid_t uid, euid, suid, fsuid; 217 gid_t gid, egid, sgid, fsgid; 218 unsigned long personality; 219 int arch; 220 221 pid_t target_pid; 222 u32 target_sid; 223 224 #if AUDIT_DEBUG 225 int put_count; 226 int ino_count; 227 #endif 228 }; 229 230 #define ACC_MODE(x) ("\004\002\006\006"[(x)&O_ACCMODE]) 231 static inline int open_arg(int flags, int mask) 232 { 233 int n = ACC_MODE(flags); 234 if (flags & (O_TRUNC | O_CREAT)) 235 n |= AUDIT_PERM_WRITE; 236 return n & mask; 237 } 238 239 static int audit_match_perm(struct audit_context *ctx, int mask) 240 { 241 unsigned n = ctx->major; 242 switch (audit_classify_syscall(ctx->arch, n)) { 243 case 0: /* native */ 244 if ((mask & AUDIT_PERM_WRITE) && 245 audit_match_class(AUDIT_CLASS_WRITE, n)) 246 return 1; 247 if ((mask & AUDIT_PERM_READ) && 248 audit_match_class(AUDIT_CLASS_READ, n)) 249 return 1; 250 if ((mask & AUDIT_PERM_ATTR) && 251 audit_match_class(AUDIT_CLASS_CHATTR, n)) 252 return 1; 253 return 0; 254 case 1: /* 32bit on biarch */ 255 if ((mask & AUDIT_PERM_WRITE) && 256 audit_match_class(AUDIT_CLASS_WRITE_32, n)) 257 return 1; 258 if ((mask & AUDIT_PERM_READ) && 259 audit_match_class(AUDIT_CLASS_READ_32, n)) 260 return 1; 261 if ((mask & AUDIT_PERM_ATTR) && 262 audit_match_class(AUDIT_CLASS_CHATTR_32, n)) 263 return 1; 264 return 0; 265 case 2: /* open */ 266 return mask & ACC_MODE(ctx->argv[1]); 267 case 3: /* openat */ 268 return mask & ACC_MODE(ctx->argv[2]); 269 case 4: /* socketcall */ 270 return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND); 271 case 5: /* execve */ 272 return mask & AUDIT_PERM_EXEC; 273 default: 274 return 0; 275 } 276 } 277 278 /* Determine if any context name data matches a rule's watch data */ 279 /* Compare a task_struct with an audit_rule. Return 1 on match, 0 280 * otherwise. */ 281 static int audit_filter_rules(struct task_struct *tsk, 282 struct audit_krule *rule, 283 struct audit_context *ctx, 284 struct audit_names *name, 285 enum audit_state *state) 286 { 287 int i, j, need_sid = 1; 288 u32 sid; 289 290 for (i = 0; i < rule->field_count; i++) { 291 struct audit_field *f = &rule->fields[i]; 292 int result = 0; 293 294 switch (f->type) { 295 case AUDIT_PID: 296 result = audit_comparator(tsk->pid, f->op, f->val); 297 break; 298 case AUDIT_PPID: 299 if (ctx) { 300 if (!ctx->ppid) 301 ctx->ppid = sys_getppid(); 302 result = audit_comparator(ctx->ppid, f->op, f->val); 303 } 304 break; 305 case AUDIT_UID: 306 result = audit_comparator(tsk->uid, f->op, f->val); 307 break; 308 case AUDIT_EUID: 309 result = audit_comparator(tsk->euid, f->op, f->val); 310 break; 311 case AUDIT_SUID: 312 result = audit_comparator(tsk->suid, f->op, f->val); 313 break; 314 case AUDIT_FSUID: 315 result = audit_comparator(tsk->fsuid, f->op, f->val); 316 break; 317 case AUDIT_GID: 318 result = audit_comparator(tsk->gid, f->op, f->val); 319 break; 320 case AUDIT_EGID: 321 result = audit_comparator(tsk->egid, f->op, f->val); 322 break; 323 case AUDIT_SGID: 324 result = audit_comparator(tsk->sgid, f->op, f->val); 325 break; 326 case AUDIT_FSGID: 327 result = audit_comparator(tsk->fsgid, f->op, f->val); 328 break; 329 case AUDIT_PERS: 330 result = audit_comparator(tsk->personality, f->op, f->val); 331 break; 332 case AUDIT_ARCH: 333 if (ctx) 334 result = audit_comparator(ctx->arch, f->op, f->val); 335 break; 336 337 case AUDIT_EXIT: 338 if (ctx && ctx->return_valid) 339 result = audit_comparator(ctx->return_code, f->op, f->val); 340 break; 341 case AUDIT_SUCCESS: 342 if (ctx && ctx->return_valid) { 343 if (f->val) 344 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); 345 else 346 result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); 347 } 348 break; 349 case AUDIT_DEVMAJOR: 350 if (name) 351 result = audit_comparator(MAJOR(name->dev), 352 f->op, f->val); 353 else if (ctx) { 354 for (j = 0; j < ctx->name_count; j++) { 355 if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) { 356 ++result; 357 break; 358 } 359 } 360 } 361 break; 362 case AUDIT_DEVMINOR: 363 if (name) 364 result = audit_comparator(MINOR(name->dev), 365 f->op, f->val); 366 else if (ctx) { 367 for (j = 0; j < ctx->name_count; j++) { 368 if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) { 369 ++result; 370 break; 371 } 372 } 373 } 374 break; 375 case AUDIT_INODE: 376 if (name) 377 result = (name->ino == f->val); 378 else if (ctx) { 379 for (j = 0; j < ctx->name_count; j++) { 380 if (audit_comparator(ctx->names[j].ino, f->op, f->val)) { 381 ++result; 382 break; 383 } 384 } 385 } 386 break; 387 case AUDIT_WATCH: 388 if (name && rule->watch->ino != (unsigned long)-1) 389 result = (name->dev == rule->watch->dev && 390 name->ino == rule->watch->ino); 391 break; 392 case AUDIT_LOGINUID: 393 result = 0; 394 if (ctx) 395 result = audit_comparator(ctx->loginuid, f->op, f->val); 396 break; 397 case AUDIT_SUBJ_USER: 398 case AUDIT_SUBJ_ROLE: 399 case AUDIT_SUBJ_TYPE: 400 case AUDIT_SUBJ_SEN: 401 case AUDIT_SUBJ_CLR: 402 /* NOTE: this may return negative values indicating 403 a temporary error. We simply treat this as a 404 match for now to avoid losing information that 405 may be wanted. An error message will also be 406 logged upon error */ 407 if (f->se_rule) { 408 if (need_sid) { 409 selinux_get_task_sid(tsk, &sid); 410 need_sid = 0; 411 } 412 result = selinux_audit_rule_match(sid, f->type, 413 f->op, 414 f->se_rule, 415 ctx); 416 } 417 break; 418 case AUDIT_OBJ_USER: 419 case AUDIT_OBJ_ROLE: 420 case AUDIT_OBJ_TYPE: 421 case AUDIT_OBJ_LEV_LOW: 422 case AUDIT_OBJ_LEV_HIGH: 423 /* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR 424 also applies here */ 425 if (f->se_rule) { 426 /* Find files that match */ 427 if (name) { 428 result = selinux_audit_rule_match( 429 name->osid, f->type, f->op, 430 f->se_rule, ctx); 431 } else if (ctx) { 432 for (j = 0; j < ctx->name_count; j++) { 433 if (selinux_audit_rule_match( 434 ctx->names[j].osid, 435 f->type, f->op, 436 f->se_rule, ctx)) { 437 ++result; 438 break; 439 } 440 } 441 } 442 /* Find ipc objects that match */ 443 if (ctx) { 444 struct audit_aux_data *aux; 445 for (aux = ctx->aux; aux; 446 aux = aux->next) { 447 if (aux->type == AUDIT_IPC) { 448 struct audit_aux_data_ipcctl *axi = (void *)aux; 449 if (selinux_audit_rule_match(axi->osid, f->type, f->op, f->se_rule, ctx)) { 450 ++result; 451 break; 452 } 453 } 454 } 455 } 456 } 457 break; 458 case AUDIT_ARG0: 459 case AUDIT_ARG1: 460 case AUDIT_ARG2: 461 case AUDIT_ARG3: 462 if (ctx) 463 result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); 464 break; 465 case AUDIT_FILTERKEY: 466 /* ignore this field for filtering */ 467 result = 1; 468 break; 469 case AUDIT_PERM: 470 result = audit_match_perm(ctx, f->val); 471 break; 472 } 473 474 if (!result) 475 return 0; 476 } 477 if (rule->filterkey) 478 ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC); 479 switch (rule->action) { 480 case AUDIT_NEVER: *state = AUDIT_DISABLED; break; 481 case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; 482 } 483 return 1; 484 } 485 486 /* At process creation time, we can determine if system-call auditing is 487 * completely disabled for this task. Since we only have the task 488 * structure at this point, we can only check uid and gid. 489 */ 490 static enum audit_state audit_filter_task(struct task_struct *tsk) 491 { 492 struct audit_entry *e; 493 enum audit_state state; 494 495 rcu_read_lock(); 496 list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) { 497 if (audit_filter_rules(tsk, &e->rule, NULL, NULL, &state)) { 498 rcu_read_unlock(); 499 return state; 500 } 501 } 502 rcu_read_unlock(); 503 return AUDIT_BUILD_CONTEXT; 504 } 505 506 /* At syscall entry and exit time, this filter is called if the 507 * audit_state is not low enough that auditing cannot take place, but is 508 * also not high enough that we already know we have to write an audit 509 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). 510 */ 511 static enum audit_state audit_filter_syscall(struct task_struct *tsk, 512 struct audit_context *ctx, 513 struct list_head *list) 514 { 515 struct audit_entry *e; 516 enum audit_state state; 517 518 if (audit_pid && tsk->tgid == audit_pid) 519 return AUDIT_DISABLED; 520 521 rcu_read_lock(); 522 if (!list_empty(list)) { 523 int word = AUDIT_WORD(ctx->major); 524 int bit = AUDIT_BIT(ctx->major); 525 526 list_for_each_entry_rcu(e, list, list) { 527 if ((e->rule.mask[word] & bit) == bit && 528 audit_filter_rules(tsk, &e->rule, ctx, NULL, 529 &state)) { 530 rcu_read_unlock(); 531 return state; 532 } 533 } 534 } 535 rcu_read_unlock(); 536 return AUDIT_BUILD_CONTEXT; 537 } 538 539 /* At syscall exit time, this filter is called if any audit_names[] have been 540 * collected during syscall processing. We only check rules in sublists at hash 541 * buckets applicable to the inode numbers in audit_names[]. 542 * Regarding audit_state, same rules apply as for audit_filter_syscall(). 543 */ 544 enum audit_state audit_filter_inodes(struct task_struct *tsk, 545 struct audit_context *ctx) 546 { 547 int i; 548 struct audit_entry *e; 549 enum audit_state state; 550 551 if (audit_pid && tsk->tgid == audit_pid) 552 return AUDIT_DISABLED; 553 554 rcu_read_lock(); 555 for (i = 0; i < ctx->name_count; i++) { 556 int word = AUDIT_WORD(ctx->major); 557 int bit = AUDIT_BIT(ctx->major); 558 struct audit_names *n = &ctx->names[i]; 559 int h = audit_hash_ino((u32)n->ino); 560 struct list_head *list = &audit_inode_hash[h]; 561 562 if (list_empty(list)) 563 continue; 564 565 list_for_each_entry_rcu(e, list, list) { 566 if ((e->rule.mask[word] & bit) == bit && 567 audit_filter_rules(tsk, &e->rule, ctx, n, &state)) { 568 rcu_read_unlock(); 569 return state; 570 } 571 } 572 } 573 rcu_read_unlock(); 574 return AUDIT_BUILD_CONTEXT; 575 } 576 577 void audit_set_auditable(struct audit_context *ctx) 578 { 579 ctx->auditable = 1; 580 } 581 582 static inline struct audit_context *audit_get_context(struct task_struct *tsk, 583 int return_valid, 584 int return_code) 585 { 586 struct audit_context *context = tsk->audit_context; 587 588 if (likely(!context)) 589 return NULL; 590 context->return_valid = return_valid; 591 context->return_code = return_code; 592 593 if (context->in_syscall && !context->dummy && !context->auditable) { 594 enum audit_state state; 595 596 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]); 597 if (state == AUDIT_RECORD_CONTEXT) { 598 context->auditable = 1; 599 goto get_context; 600 } 601 602 state = audit_filter_inodes(tsk, context); 603 if (state == AUDIT_RECORD_CONTEXT) 604 context->auditable = 1; 605 606 } 607 608 get_context: 609 610 tsk->audit_context = NULL; 611 return context; 612 } 613 614 static inline void audit_free_names(struct audit_context *context) 615 { 616 int i; 617 618 #if AUDIT_DEBUG == 2 619 if (context->auditable 620 ||context->put_count + context->ino_count != context->name_count) { 621 printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" 622 " name_count=%d put_count=%d" 623 " ino_count=%d [NOT freeing]\n", 624 __FILE__, __LINE__, 625 context->serial, context->major, context->in_syscall, 626 context->name_count, context->put_count, 627 context->ino_count); 628 for (i = 0; i < context->name_count; i++) { 629 printk(KERN_ERR "names[%d] = %p = %s\n", i, 630 context->names[i].name, 631 context->names[i].name ?: "(null)"); 632 } 633 dump_stack(); 634 return; 635 } 636 #endif 637 #if AUDIT_DEBUG 638 context->put_count = 0; 639 context->ino_count = 0; 640 #endif 641 642 for (i = 0; i < context->name_count; i++) { 643 if (context->names[i].name && context->names[i].name_put) 644 __putname(context->names[i].name); 645 } 646 context->name_count = 0; 647 if (context->pwd) 648 dput(context->pwd); 649 if (context->pwdmnt) 650 mntput(context->pwdmnt); 651 context->pwd = NULL; 652 context->pwdmnt = NULL; 653 } 654 655 static inline void audit_free_aux(struct audit_context *context) 656 { 657 struct audit_aux_data *aux; 658 659 while ((aux = context->aux)) { 660 if (aux->type == AUDIT_AVC_PATH) { 661 struct audit_aux_data_path *axi = (void *)aux; 662 dput(axi->dentry); 663 mntput(axi->mnt); 664 } 665 666 context->aux = aux->next; 667 kfree(aux); 668 } 669 while ((aux = context->aux_pids)) { 670 context->aux_pids = aux->next; 671 kfree(aux); 672 } 673 } 674 675 static inline void audit_zero_context(struct audit_context *context, 676 enum audit_state state) 677 { 678 uid_t loginuid = context->loginuid; 679 680 memset(context, 0, sizeof(*context)); 681 context->state = state; 682 context->loginuid = loginuid; 683 } 684 685 static inline struct audit_context *audit_alloc_context(enum audit_state state) 686 { 687 struct audit_context *context; 688 689 if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) 690 return NULL; 691 audit_zero_context(context, state); 692 return context; 693 } 694 695 /** 696 * audit_alloc - allocate an audit context block for a task 697 * @tsk: task 698 * 699 * Filter on the task information and allocate a per-task audit context 700 * if necessary. Doing so turns on system call auditing for the 701 * specified task. This is called from copy_process, so no lock is 702 * needed. 703 */ 704 int audit_alloc(struct task_struct *tsk) 705 { 706 struct audit_context *context; 707 enum audit_state state; 708 709 if (likely(!audit_enabled)) 710 return 0; /* Return if not auditing. */ 711 712 state = audit_filter_task(tsk); 713 if (likely(state == AUDIT_DISABLED)) 714 return 0; 715 716 if (!(context = audit_alloc_context(state))) { 717 audit_log_lost("out of memory in audit_alloc"); 718 return -ENOMEM; 719 } 720 721 /* Preserve login uid */ 722 context->loginuid = -1; 723 if (current->audit_context) 724 context->loginuid = current->audit_context->loginuid; 725 726 tsk->audit_context = context; 727 set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); 728 return 0; 729 } 730 731 static inline void audit_free_context(struct audit_context *context) 732 { 733 struct audit_context *previous; 734 int count = 0; 735 736 do { 737 previous = context->previous; 738 if (previous || (count && count < 10)) { 739 ++count; 740 printk(KERN_ERR "audit(:%d): major=%d name_count=%d:" 741 " freeing multiple contexts (%d)\n", 742 context->serial, context->major, 743 context->name_count, count); 744 } 745 audit_free_names(context); 746 audit_free_aux(context); 747 kfree(context->filterkey); 748 kfree(context); 749 context = previous; 750 } while (context); 751 if (count >= 10) 752 printk(KERN_ERR "audit: freed %d contexts\n", count); 753 } 754 755 void audit_log_task_context(struct audit_buffer *ab) 756 { 757 char *ctx = NULL; 758 unsigned len; 759 int error; 760 u32 sid; 761 762 selinux_get_task_sid(current, &sid); 763 if (!sid) 764 return; 765 766 error = selinux_sid_to_string(sid, &ctx, &len); 767 if (error) { 768 if (error != -EINVAL) 769 goto error_path; 770 return; 771 } 772 773 audit_log_format(ab, " subj=%s", ctx); 774 kfree(ctx); 775 return; 776 777 error_path: 778 audit_panic("error in audit_log_task_context"); 779 return; 780 } 781 782 EXPORT_SYMBOL(audit_log_task_context); 783 784 static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) 785 { 786 char name[sizeof(tsk->comm)]; 787 struct mm_struct *mm = tsk->mm; 788 struct vm_area_struct *vma; 789 790 /* tsk == current */ 791 792 get_task_comm(name, tsk); 793 audit_log_format(ab, " comm="); 794 audit_log_untrustedstring(ab, name); 795 796 if (mm) { 797 down_read(&mm->mmap_sem); 798 vma = mm->mmap; 799 while (vma) { 800 if ((vma->vm_flags & VM_EXECUTABLE) && 801 vma->vm_file) { 802 audit_log_d_path(ab, "exe=", 803 vma->vm_file->f_path.dentry, 804 vma->vm_file->f_path.mnt); 805 break; 806 } 807 vma = vma->vm_next; 808 } 809 up_read(&mm->mmap_sem); 810 } 811 audit_log_task_context(ab); 812 } 813 814 static int audit_log_pid_context(struct audit_context *context, pid_t pid, 815 u32 sid) 816 { 817 struct audit_buffer *ab; 818 char *s = NULL; 819 u32 len; 820 int rc = 0; 821 822 ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); 823 if (!ab) 824 return 1; 825 826 if (selinux_sid_to_string(sid, &s, &len)) { 827 audit_log_format(ab, "opid=%d obj=(none)", pid); 828 rc = 1; 829 } else 830 audit_log_format(ab, "opid=%d obj=%s", pid, s); 831 audit_log_end(ab); 832 kfree(s); 833 834 return rc; 835 } 836 837 static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) 838 { 839 int i, call_panic = 0; 840 struct audit_buffer *ab; 841 struct audit_aux_data *aux; 842 const char *tty; 843 844 /* tsk == current */ 845 context->pid = tsk->pid; 846 if (!context->ppid) 847 context->ppid = sys_getppid(); 848 context->uid = tsk->uid; 849 context->gid = tsk->gid; 850 context->euid = tsk->euid; 851 context->suid = tsk->suid; 852 context->fsuid = tsk->fsuid; 853 context->egid = tsk->egid; 854 context->sgid = tsk->sgid; 855 context->fsgid = tsk->fsgid; 856 context->personality = tsk->personality; 857 858 ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL); 859 if (!ab) 860 return; /* audit_panic has been called */ 861 audit_log_format(ab, "arch=%x syscall=%d", 862 context->arch, context->major); 863 if (context->personality != PER_LINUX) 864 audit_log_format(ab, " per=%lx", context->personality); 865 if (context->return_valid) 866 audit_log_format(ab, " success=%s exit=%ld", 867 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", 868 context->return_code); 869 870 mutex_lock(&tty_mutex); 871 read_lock(&tasklist_lock); 872 if (tsk->signal && tsk->signal->tty && tsk->signal->tty->name) 873 tty = tsk->signal->tty->name; 874 else 875 tty = "(none)"; 876 read_unlock(&tasklist_lock); 877 audit_log_format(ab, 878 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" 879 " ppid=%d pid=%d auid=%u uid=%u gid=%u" 880 " euid=%u suid=%u fsuid=%u" 881 " egid=%u sgid=%u fsgid=%u tty=%s", 882 context->argv[0], 883 context->argv[1], 884 context->argv[2], 885 context->argv[3], 886 context->name_count, 887 context->ppid, 888 context->pid, 889 context->loginuid, 890 context->uid, 891 context->gid, 892 context->euid, context->suid, context->fsuid, 893 context->egid, context->sgid, context->fsgid, tty); 894 895 mutex_unlock(&tty_mutex); 896 897 audit_log_task_info(ab, tsk); 898 if (context->filterkey) { 899 audit_log_format(ab, " key="); 900 audit_log_untrustedstring(ab, context->filterkey); 901 } else 902 audit_log_format(ab, " key=(null)"); 903 audit_log_end(ab); 904 905 for (aux = context->aux; aux; aux = aux->next) { 906 907 ab = audit_log_start(context, GFP_KERNEL, aux->type); 908 if (!ab) 909 continue; /* audit_panic has been called */ 910 911 switch (aux->type) { 912 case AUDIT_MQ_OPEN: { 913 struct audit_aux_data_mq_open *axi = (void *)aux; 914 audit_log_format(ab, 915 "oflag=0x%x mode=%#o mq_flags=0x%lx mq_maxmsg=%ld " 916 "mq_msgsize=%ld mq_curmsgs=%ld", 917 axi->oflag, axi->mode, axi->attr.mq_flags, 918 axi->attr.mq_maxmsg, axi->attr.mq_msgsize, 919 axi->attr.mq_curmsgs); 920 break; } 921 922 case AUDIT_MQ_SENDRECV: { 923 struct audit_aux_data_mq_sendrecv *axi = (void *)aux; 924 audit_log_format(ab, 925 "mqdes=%d msg_len=%zd msg_prio=%u " 926 "abs_timeout_sec=%ld abs_timeout_nsec=%ld", 927 axi->mqdes, axi->msg_len, axi->msg_prio, 928 axi->abs_timeout.tv_sec, axi->abs_timeout.tv_nsec); 929 break; } 930 931 case AUDIT_MQ_NOTIFY: { 932 struct audit_aux_data_mq_notify *axi = (void *)aux; 933 audit_log_format(ab, 934 "mqdes=%d sigev_signo=%d", 935 axi->mqdes, 936 axi->notification.sigev_signo); 937 break; } 938 939 case AUDIT_MQ_GETSETATTR: { 940 struct audit_aux_data_mq_getsetattr *axi = (void *)aux; 941 audit_log_format(ab, 942 "mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld " 943 "mq_curmsgs=%ld ", 944 axi->mqdes, 945 axi->mqstat.mq_flags, axi->mqstat.mq_maxmsg, 946 axi->mqstat.mq_msgsize, axi->mqstat.mq_curmsgs); 947 break; } 948 949 case AUDIT_IPC: { 950 struct audit_aux_data_ipcctl *axi = (void *)aux; 951 audit_log_format(ab, 952 "ouid=%u ogid=%u mode=%x", 953 axi->uid, axi->gid, axi->mode); 954 if (axi->osid != 0) { 955 char *ctx = NULL; 956 u32 len; 957 if (selinux_sid_to_string( 958 axi->osid, &ctx, &len)) { 959 audit_log_format(ab, " osid=%u", 960 axi->osid); 961 call_panic = 1; 962 } else 963 audit_log_format(ab, " obj=%s", ctx); 964 kfree(ctx); 965 } 966 break; } 967 968 case AUDIT_IPC_SET_PERM: { 969 struct audit_aux_data_ipcctl *axi = (void *)aux; 970 audit_log_format(ab, 971 "qbytes=%lx ouid=%u ogid=%u mode=%x", 972 axi->qbytes, axi->uid, axi->gid, axi->mode); 973 break; } 974 975 case AUDIT_EXECVE: { 976 struct audit_aux_data_execve *axi = (void *)aux; 977 int i; 978 const char *p; 979 for (i = 0, p = axi->mem; i < axi->argc; i++) { 980 audit_log_format(ab, "a%d=", i); 981 p = audit_log_untrustedstring(ab, p); 982 audit_log_format(ab, "\n"); 983 } 984 break; } 985 986 case AUDIT_SOCKETCALL: { 987 int i; 988 struct audit_aux_data_socketcall *axs = (void *)aux; 989 audit_log_format(ab, "nargs=%d", axs->nargs); 990 for (i=0; i<axs->nargs; i++) 991 audit_log_format(ab, " a%d=%lx", i, axs->args[i]); 992 break; } 993 994 case AUDIT_SOCKADDR: { 995 struct audit_aux_data_sockaddr *axs = (void *)aux; 996 997 audit_log_format(ab, "saddr="); 998 audit_log_hex(ab, axs->a, axs->len); 999 break; } 1000 1001 case AUDIT_AVC_PATH: { 1002 struct audit_aux_data_path *axi = (void *)aux; 1003 audit_log_d_path(ab, "path=", axi->dentry, axi->mnt); 1004 break; } 1005 1006 case AUDIT_FD_PAIR: { 1007 struct audit_aux_data_fd_pair *axs = (void *)aux; 1008 audit_log_format(ab, "fd0=%d fd1=%d", axs->fd[0], axs->fd[1]); 1009 break; } 1010 1011 } 1012 audit_log_end(ab); 1013 } 1014 1015 for (aux = context->aux_pids; aux; aux = aux->next) { 1016 struct audit_aux_data_pids *axs = (void *)aux; 1017 int i; 1018 1019 for (i = 0; i < axs->pid_count; i++) 1020 if (audit_log_pid_context(context, axs->target_pid[i], 1021 axs->target_sid[i])) 1022 call_panic = 1; 1023 } 1024 1025 if (context->target_pid && 1026 audit_log_pid_context(context, context->target_pid, 1027 context->target_sid)) 1028 call_panic = 1; 1029 1030 if (context->pwd && context->pwdmnt) { 1031 ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD); 1032 if (ab) { 1033 audit_log_d_path(ab, "cwd=", context->pwd, context->pwdmnt); 1034 audit_log_end(ab); 1035 } 1036 } 1037 for (i = 0; i < context->name_count; i++) { 1038 struct audit_names *n = &context->names[i]; 1039 1040 ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH); 1041 if (!ab) 1042 continue; /* audit_panic has been called */ 1043 1044 audit_log_format(ab, "item=%d", i); 1045 1046 if (n->name) { 1047 switch(n->name_len) { 1048 case AUDIT_NAME_FULL: 1049 /* log the full path */ 1050 audit_log_format(ab, " name="); 1051 audit_log_untrustedstring(ab, n->name); 1052 break; 1053 case 0: 1054 /* name was specified as a relative path and the 1055 * directory component is the cwd */ 1056 audit_log_d_path(ab, " name=", context->pwd, 1057 context->pwdmnt); 1058 break; 1059 default: 1060 /* log the name's directory component */ 1061 audit_log_format(ab, " name="); 1062 audit_log_n_untrustedstring(ab, n->name_len, 1063 n->name); 1064 } 1065 } else 1066 audit_log_format(ab, " name=(null)"); 1067 1068 if (n->ino != (unsigned long)-1) { 1069 audit_log_format(ab, " inode=%lu" 1070 " dev=%02x:%02x mode=%#o" 1071 " ouid=%u ogid=%u rdev=%02x:%02x", 1072 n->ino, 1073 MAJOR(n->dev), 1074 MINOR(n->dev), 1075 n->mode, 1076 n->uid, 1077 n->gid, 1078 MAJOR(n->rdev), 1079 MINOR(n->rdev)); 1080 } 1081 if (n->osid != 0) { 1082 char *ctx = NULL; 1083 u32 len; 1084 if (selinux_sid_to_string( 1085 n->osid, &ctx, &len)) { 1086 audit_log_format(ab, " osid=%u", n->osid); 1087 call_panic = 2; 1088 } else 1089 audit_log_format(ab, " obj=%s", ctx); 1090 kfree(ctx); 1091 } 1092 1093 audit_log_end(ab); 1094 } 1095 if (call_panic) 1096 audit_panic("error converting sid to string"); 1097 } 1098 1099 /** 1100 * audit_free - free a per-task audit context 1101 * @tsk: task whose audit context block to free 1102 * 1103 * Called from copy_process and do_exit 1104 */ 1105 void audit_free(struct task_struct *tsk) 1106 { 1107 struct audit_context *context; 1108 1109 context = audit_get_context(tsk, 0, 0); 1110 if (likely(!context)) 1111 return; 1112 1113 /* Check for system calls that do not go through the exit 1114 * function (e.g., exit_group), then free context block. 1115 * We use GFP_ATOMIC here because we might be doing this 1116 * in the context of the idle thread */ 1117 /* that can happen only if we are called from do_exit() */ 1118 if (context->in_syscall && context->auditable) 1119 audit_log_exit(context, tsk); 1120 1121 audit_free_context(context); 1122 } 1123 1124 /** 1125 * audit_syscall_entry - fill in an audit record at syscall entry 1126 * @tsk: task being audited 1127 * @arch: architecture type 1128 * @major: major syscall type (function) 1129 * @a1: additional syscall register 1 1130 * @a2: additional syscall register 2 1131 * @a3: additional syscall register 3 1132 * @a4: additional syscall register 4 1133 * 1134 * Fill in audit context at syscall entry. This only happens if the 1135 * audit context was created when the task was created and the state or 1136 * filters demand the audit context be built. If the state from the 1137 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, 1138 * then the record will be written at syscall exit time (otherwise, it 1139 * will only be written if another part of the kernel requests that it 1140 * be written). 1141 */ 1142 void audit_syscall_entry(int arch, int major, 1143 unsigned long a1, unsigned long a2, 1144 unsigned long a3, unsigned long a4) 1145 { 1146 struct task_struct *tsk = current; 1147 struct audit_context *context = tsk->audit_context; 1148 enum audit_state state; 1149 1150 BUG_ON(!context); 1151 1152 /* 1153 * This happens only on certain architectures that make system 1154 * calls in kernel_thread via the entry.S interface, instead of 1155 * with direct calls. (If you are porting to a new 1156 * architecture, hitting this condition can indicate that you 1157 * got the _exit/_leave calls backward in entry.S.) 1158 * 1159 * i386 no 1160 * x86_64 no 1161 * ppc64 yes (see arch/powerpc/platforms/iseries/misc.S) 1162 * 1163 * This also happens with vm86 emulation in a non-nested manner 1164 * (entries without exits), so this case must be caught. 1165 */ 1166 if (context->in_syscall) { 1167 struct audit_context *newctx; 1168 1169 #if AUDIT_DEBUG 1170 printk(KERN_ERR 1171 "audit(:%d) pid=%d in syscall=%d;" 1172 " entering syscall=%d\n", 1173 context->serial, tsk->pid, context->major, major); 1174 #endif 1175 newctx = audit_alloc_context(context->state); 1176 if (newctx) { 1177 newctx->previous = context; 1178 context = newctx; 1179 tsk->audit_context = newctx; 1180 } else { 1181 /* If we can't alloc a new context, the best we 1182 * can do is to leak memory (any pending putname 1183 * will be lost). The only other alternative is 1184 * to abandon auditing. */ 1185 audit_zero_context(context, context->state); 1186 } 1187 } 1188 BUG_ON(context->in_syscall || context->name_count); 1189 1190 if (!audit_enabled) 1191 return; 1192 1193 context->arch = arch; 1194 context->major = major; 1195 context->argv[0] = a1; 1196 context->argv[1] = a2; 1197 context->argv[2] = a3; 1198 context->argv[3] = a4; 1199 1200 state = context->state; 1201 context->dummy = !audit_n_rules; 1202 if (!context->dummy && (state == AUDIT_SETUP_CONTEXT || state == AUDIT_BUILD_CONTEXT)) 1203 state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]); 1204 if (likely(state == AUDIT_DISABLED)) 1205 return; 1206 1207 context->serial = 0; 1208 context->ctime = CURRENT_TIME; 1209 context->in_syscall = 1; 1210 context->auditable = !!(state == AUDIT_RECORD_CONTEXT); 1211 context->ppid = 0; 1212 } 1213 1214 /** 1215 * audit_syscall_exit - deallocate audit context after a system call 1216 * @tsk: task being audited 1217 * @valid: success/failure flag 1218 * @return_code: syscall return value 1219 * 1220 * Tear down after system call. If the audit context has been marked as 1221 * auditable (either because of the AUDIT_RECORD_CONTEXT state from 1222 * filtering, or because some other part of the kernel write an audit 1223 * message), then write out the syscall information. In call cases, 1224 * free the names stored from getname(). 1225 */ 1226 void audit_syscall_exit(int valid, long return_code) 1227 { 1228 struct task_struct *tsk = current; 1229 struct audit_context *context; 1230 1231 context = audit_get_context(tsk, valid, return_code); 1232 1233 if (likely(!context)) 1234 return; 1235 1236 if (context->in_syscall && context->auditable) 1237 audit_log_exit(context, tsk); 1238 1239 context->in_syscall = 0; 1240 context->auditable = 0; 1241 1242 if (context->previous) { 1243 struct audit_context *new_context = context->previous; 1244 context->previous = NULL; 1245 audit_free_context(context); 1246 tsk->audit_context = new_context; 1247 } else { 1248 audit_free_names(context); 1249 audit_free_aux(context); 1250 context->aux = NULL; 1251 context->aux_pids = NULL; 1252 context->target_pid = 0; 1253 context->target_sid = 0; 1254 kfree(context->filterkey); 1255 context->filterkey = NULL; 1256 tsk->audit_context = context; 1257 } 1258 } 1259 1260 /** 1261 * audit_getname - add a name to the list 1262 * @name: name to add 1263 * 1264 * Add a name to the list of audit names for this context. 1265 * Called from fs/namei.c:getname(). 1266 */ 1267 void __audit_getname(const char *name) 1268 { 1269 struct audit_context *context = current->audit_context; 1270 1271 if (IS_ERR(name) || !name) 1272 return; 1273 1274 if (!context->in_syscall) { 1275 #if AUDIT_DEBUG == 2 1276 printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n", 1277 __FILE__, __LINE__, context->serial, name); 1278 dump_stack(); 1279 #endif 1280 return; 1281 } 1282 BUG_ON(context->name_count >= AUDIT_NAMES); 1283 context->names[context->name_count].name = name; 1284 context->names[context->name_count].name_len = AUDIT_NAME_FULL; 1285 context->names[context->name_count].name_put = 1; 1286 context->names[context->name_count].ino = (unsigned long)-1; 1287 context->names[context->name_count].osid = 0; 1288 ++context->name_count; 1289 if (!context->pwd) { 1290 read_lock(¤t->fs->lock); 1291 context->pwd = dget(current->fs->pwd); 1292 context->pwdmnt = mntget(current->fs->pwdmnt); 1293 read_unlock(¤t->fs->lock); 1294 } 1295 1296 } 1297 1298 /* audit_putname - intercept a putname request 1299 * @name: name to intercept and delay for putname 1300 * 1301 * If we have stored the name from getname in the audit context, 1302 * then we delay the putname until syscall exit. 1303 * Called from include/linux/fs.h:putname(). 1304 */ 1305 void audit_putname(const char *name) 1306 { 1307 struct audit_context *context = current->audit_context; 1308 1309 BUG_ON(!context); 1310 if (!context->in_syscall) { 1311 #if AUDIT_DEBUG == 2 1312 printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n", 1313 __FILE__, __LINE__, context->serial, name); 1314 if (context->name_count) { 1315 int i; 1316 for (i = 0; i < context->name_count; i++) 1317 printk(KERN_ERR "name[%d] = %p = %s\n", i, 1318 context->names[i].name, 1319 context->names[i].name ?: "(null)"); 1320 } 1321 #endif 1322 __putname(name); 1323 } 1324 #if AUDIT_DEBUG 1325 else { 1326 ++context->put_count; 1327 if (context->put_count > context->name_count) { 1328 printk(KERN_ERR "%s:%d(:%d): major=%d" 1329 " in_syscall=%d putname(%p) name_count=%d" 1330 " put_count=%d\n", 1331 __FILE__, __LINE__, 1332 context->serial, context->major, 1333 context->in_syscall, name, context->name_count, 1334 context->put_count); 1335 dump_stack(); 1336 } 1337 } 1338 #endif 1339 } 1340 1341 static int audit_inc_name_count(struct audit_context *context, 1342 const struct inode *inode) 1343 { 1344 if (context->name_count >= AUDIT_NAMES) { 1345 if (inode) 1346 printk(KERN_DEBUG "name_count maxed, losing inode data: " 1347 "dev=%02x:%02x, inode=%lu", 1348 MAJOR(inode->i_sb->s_dev), 1349 MINOR(inode->i_sb->s_dev), 1350 inode->i_ino); 1351 1352 else 1353 printk(KERN_DEBUG "name_count maxed, losing inode data"); 1354 return 1; 1355 } 1356 context->name_count++; 1357 #if AUDIT_DEBUG 1358 context->ino_count++; 1359 #endif 1360 return 0; 1361 } 1362 1363 /* Copy inode data into an audit_names. */ 1364 static void audit_copy_inode(struct audit_names *name, const struct inode *inode) 1365 { 1366 name->ino = inode->i_ino; 1367 name->dev = inode->i_sb->s_dev; 1368 name->mode = inode->i_mode; 1369 name->uid = inode->i_uid; 1370 name->gid = inode->i_gid; 1371 name->rdev = inode->i_rdev; 1372 selinux_get_inode_sid(inode, &name->osid); 1373 } 1374 1375 /** 1376 * audit_inode - store the inode and device from a lookup 1377 * @name: name being audited 1378 * @inode: inode being audited 1379 * 1380 * Called from fs/namei.c:path_lookup(). 1381 */ 1382 void __audit_inode(const char *name, const struct inode *inode) 1383 { 1384 int idx; 1385 struct audit_context *context = current->audit_context; 1386 1387 if (!context->in_syscall) 1388 return; 1389 if (context->name_count 1390 && context->names[context->name_count-1].name 1391 && context->names[context->name_count-1].name == name) 1392 idx = context->name_count - 1; 1393 else if (context->name_count > 1 1394 && context->names[context->name_count-2].name 1395 && context->names[context->name_count-2].name == name) 1396 idx = context->name_count - 2; 1397 else { 1398 /* FIXME: how much do we care about inodes that have no 1399 * associated name? */ 1400 if (audit_inc_name_count(context, inode)) 1401 return; 1402 idx = context->name_count - 1; 1403 context->names[idx].name = NULL; 1404 } 1405 audit_copy_inode(&context->names[idx], inode); 1406 } 1407 1408 /** 1409 * audit_inode_child - collect inode info for created/removed objects 1410 * @dname: inode's dentry name 1411 * @inode: inode being audited 1412 * @parent: inode of dentry parent 1413 * 1414 * For syscalls that create or remove filesystem objects, audit_inode 1415 * can only collect information for the filesystem object's parent. 1416 * This call updates the audit context with the child's information. 1417 * Syscalls that create a new filesystem object must be hooked after 1418 * the object is created. Syscalls that remove a filesystem object 1419 * must be hooked prior, in order to capture the target inode during 1420 * unsuccessful attempts. 1421 */ 1422 void __audit_inode_child(const char *dname, const struct inode *inode, 1423 const struct inode *parent) 1424 { 1425 int idx; 1426 struct audit_context *context = current->audit_context; 1427 const char *found_parent = NULL, *found_child = NULL; 1428 int dirlen = 0; 1429 1430 if (!context->in_syscall) 1431 return; 1432 1433 /* determine matching parent */ 1434 if (!dname) 1435 goto add_names; 1436 1437 /* parent is more likely, look for it first */ 1438 for (idx = 0; idx < context->name_count; idx++) { 1439 struct audit_names *n = &context->names[idx]; 1440 1441 if (!n->name) 1442 continue; 1443 1444 if (n->ino == parent->i_ino && 1445 !audit_compare_dname_path(dname, n->name, &dirlen)) { 1446 n->name_len = dirlen; /* update parent data in place */ 1447 found_parent = n->name; 1448 goto add_names; 1449 } 1450 } 1451 1452 /* no matching parent, look for matching child */ 1453 for (idx = 0; idx < context->name_count; idx++) { 1454 struct audit_names *n = &context->names[idx]; 1455 1456 if (!n->name) 1457 continue; 1458 1459 /* strcmp() is the more likely scenario */ 1460 if (!strcmp(dname, n->name) || 1461 !audit_compare_dname_path(dname, n->name, &dirlen)) { 1462 if (inode) 1463 audit_copy_inode(n, inode); 1464 else 1465 n->ino = (unsigned long)-1; 1466 found_child = n->name; 1467 goto add_names; 1468 } 1469 } 1470 1471 add_names: 1472 if (!found_parent) { 1473 if (audit_inc_name_count(context, parent)) 1474 return; 1475 idx = context->name_count - 1; 1476 context->names[idx].name = NULL; 1477 audit_copy_inode(&context->names[idx], parent); 1478 } 1479 1480 if (!found_child) { 1481 if (audit_inc_name_count(context, inode)) 1482 return; 1483 idx = context->name_count - 1; 1484 1485 /* Re-use the name belonging to the slot for a matching parent 1486 * directory. All names for this context are relinquished in 1487 * audit_free_names() */ 1488 if (found_parent) { 1489 context->names[idx].name = found_parent; 1490 context->names[idx].name_len = AUDIT_NAME_FULL; 1491 /* don't call __putname() */ 1492 context->names[idx].name_put = 0; 1493 } else { 1494 context->names[idx].name = NULL; 1495 } 1496 1497 if (inode) 1498 audit_copy_inode(&context->names[idx], inode); 1499 else 1500 context->names[idx].ino = (unsigned long)-1; 1501 } 1502 } 1503 1504 /** 1505 * auditsc_get_stamp - get local copies of audit_context values 1506 * @ctx: audit_context for the task 1507 * @t: timespec to store time recorded in the audit_context 1508 * @serial: serial value that is recorded in the audit_context 1509 * 1510 * Also sets the context as auditable. 1511 */ 1512 void auditsc_get_stamp(struct audit_context *ctx, 1513 struct timespec *t, unsigned int *serial) 1514 { 1515 if (!ctx->serial) 1516 ctx->serial = audit_serial(); 1517 t->tv_sec = ctx->ctime.tv_sec; 1518 t->tv_nsec = ctx->ctime.tv_nsec; 1519 *serial = ctx->serial; 1520 ctx->auditable = 1; 1521 } 1522 1523 /** 1524 * audit_set_loginuid - set a task's audit_context loginuid 1525 * @task: task whose audit context is being modified 1526 * @loginuid: loginuid value 1527 * 1528 * Returns 0. 1529 * 1530 * Called (set) from fs/proc/base.c::proc_loginuid_write(). 1531 */ 1532 int audit_set_loginuid(struct task_struct *task, uid_t loginuid) 1533 { 1534 struct audit_context *context = task->audit_context; 1535 1536 if (context) { 1537 /* Only log if audit is enabled */ 1538 if (context->in_syscall) { 1539 struct audit_buffer *ab; 1540 1541 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); 1542 if (ab) { 1543 audit_log_format(ab, "login pid=%d uid=%u " 1544 "old auid=%u new auid=%u", 1545 task->pid, task->uid, 1546 context->loginuid, loginuid); 1547 audit_log_end(ab); 1548 } 1549 } 1550 context->loginuid = loginuid; 1551 } 1552 return 0; 1553 } 1554 1555 /** 1556 * audit_get_loginuid - get the loginuid for an audit_context 1557 * @ctx: the audit_context 1558 * 1559 * Returns the context's loginuid or -1 if @ctx is NULL. 1560 */ 1561 uid_t audit_get_loginuid(struct audit_context *ctx) 1562 { 1563 return ctx ? ctx->loginuid : -1; 1564 } 1565 1566 EXPORT_SYMBOL(audit_get_loginuid); 1567 1568 /** 1569 * __audit_mq_open - record audit data for a POSIX MQ open 1570 * @oflag: open flag 1571 * @mode: mode bits 1572 * @u_attr: queue attributes 1573 * 1574 * Returns 0 for success or NULL context or < 0 on error. 1575 */ 1576 int __audit_mq_open(int oflag, mode_t mode, struct mq_attr __user *u_attr) 1577 { 1578 struct audit_aux_data_mq_open *ax; 1579 struct audit_context *context = current->audit_context; 1580 1581 if (!audit_enabled) 1582 return 0; 1583 1584 if (likely(!context)) 1585 return 0; 1586 1587 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1588 if (!ax) 1589 return -ENOMEM; 1590 1591 if (u_attr != NULL) { 1592 if (copy_from_user(&ax->attr, u_attr, sizeof(ax->attr))) { 1593 kfree(ax); 1594 return -EFAULT; 1595 } 1596 } else 1597 memset(&ax->attr, 0, sizeof(ax->attr)); 1598 1599 ax->oflag = oflag; 1600 ax->mode = mode; 1601 1602 ax->d.type = AUDIT_MQ_OPEN; 1603 ax->d.next = context->aux; 1604 context->aux = (void *)ax; 1605 return 0; 1606 } 1607 1608 /** 1609 * __audit_mq_timedsend - record audit data for a POSIX MQ timed send 1610 * @mqdes: MQ descriptor 1611 * @msg_len: Message length 1612 * @msg_prio: Message priority 1613 * @u_abs_timeout: Message timeout in absolute time 1614 * 1615 * Returns 0 for success or NULL context or < 0 on error. 1616 */ 1617 int __audit_mq_timedsend(mqd_t mqdes, size_t msg_len, unsigned int msg_prio, 1618 const struct timespec __user *u_abs_timeout) 1619 { 1620 struct audit_aux_data_mq_sendrecv *ax; 1621 struct audit_context *context = current->audit_context; 1622 1623 if (!audit_enabled) 1624 return 0; 1625 1626 if (likely(!context)) 1627 return 0; 1628 1629 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1630 if (!ax) 1631 return -ENOMEM; 1632 1633 if (u_abs_timeout != NULL) { 1634 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) { 1635 kfree(ax); 1636 return -EFAULT; 1637 } 1638 } else 1639 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout)); 1640 1641 ax->mqdes = mqdes; 1642 ax->msg_len = msg_len; 1643 ax->msg_prio = msg_prio; 1644 1645 ax->d.type = AUDIT_MQ_SENDRECV; 1646 ax->d.next = context->aux; 1647 context->aux = (void *)ax; 1648 return 0; 1649 } 1650 1651 /** 1652 * __audit_mq_timedreceive - record audit data for a POSIX MQ timed receive 1653 * @mqdes: MQ descriptor 1654 * @msg_len: Message length 1655 * @u_msg_prio: Message priority 1656 * @u_abs_timeout: Message timeout in absolute time 1657 * 1658 * Returns 0 for success or NULL context or < 0 on error. 1659 */ 1660 int __audit_mq_timedreceive(mqd_t mqdes, size_t msg_len, 1661 unsigned int __user *u_msg_prio, 1662 const struct timespec __user *u_abs_timeout) 1663 { 1664 struct audit_aux_data_mq_sendrecv *ax; 1665 struct audit_context *context = current->audit_context; 1666 1667 if (!audit_enabled) 1668 return 0; 1669 1670 if (likely(!context)) 1671 return 0; 1672 1673 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1674 if (!ax) 1675 return -ENOMEM; 1676 1677 if (u_msg_prio != NULL) { 1678 if (get_user(ax->msg_prio, u_msg_prio)) { 1679 kfree(ax); 1680 return -EFAULT; 1681 } 1682 } else 1683 ax->msg_prio = 0; 1684 1685 if (u_abs_timeout != NULL) { 1686 if (copy_from_user(&ax->abs_timeout, u_abs_timeout, sizeof(ax->abs_timeout))) { 1687 kfree(ax); 1688 return -EFAULT; 1689 } 1690 } else 1691 memset(&ax->abs_timeout, 0, sizeof(ax->abs_timeout)); 1692 1693 ax->mqdes = mqdes; 1694 ax->msg_len = msg_len; 1695 1696 ax->d.type = AUDIT_MQ_SENDRECV; 1697 ax->d.next = context->aux; 1698 context->aux = (void *)ax; 1699 return 0; 1700 } 1701 1702 /** 1703 * __audit_mq_notify - record audit data for a POSIX MQ notify 1704 * @mqdes: MQ descriptor 1705 * @u_notification: Notification event 1706 * 1707 * Returns 0 for success or NULL context or < 0 on error. 1708 */ 1709 1710 int __audit_mq_notify(mqd_t mqdes, const struct sigevent __user *u_notification) 1711 { 1712 struct audit_aux_data_mq_notify *ax; 1713 struct audit_context *context = current->audit_context; 1714 1715 if (!audit_enabled) 1716 return 0; 1717 1718 if (likely(!context)) 1719 return 0; 1720 1721 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1722 if (!ax) 1723 return -ENOMEM; 1724 1725 if (u_notification != NULL) { 1726 if (copy_from_user(&ax->notification, u_notification, sizeof(ax->notification))) { 1727 kfree(ax); 1728 return -EFAULT; 1729 } 1730 } else 1731 memset(&ax->notification, 0, sizeof(ax->notification)); 1732 1733 ax->mqdes = mqdes; 1734 1735 ax->d.type = AUDIT_MQ_NOTIFY; 1736 ax->d.next = context->aux; 1737 context->aux = (void *)ax; 1738 return 0; 1739 } 1740 1741 /** 1742 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute 1743 * @mqdes: MQ descriptor 1744 * @mqstat: MQ flags 1745 * 1746 * Returns 0 for success or NULL context or < 0 on error. 1747 */ 1748 int __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat) 1749 { 1750 struct audit_aux_data_mq_getsetattr *ax; 1751 struct audit_context *context = current->audit_context; 1752 1753 if (!audit_enabled) 1754 return 0; 1755 1756 if (likely(!context)) 1757 return 0; 1758 1759 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1760 if (!ax) 1761 return -ENOMEM; 1762 1763 ax->mqdes = mqdes; 1764 ax->mqstat = *mqstat; 1765 1766 ax->d.type = AUDIT_MQ_GETSETATTR; 1767 ax->d.next = context->aux; 1768 context->aux = (void *)ax; 1769 return 0; 1770 } 1771 1772 /** 1773 * audit_ipc_obj - record audit data for ipc object 1774 * @ipcp: ipc permissions 1775 * 1776 * Returns 0 for success or NULL context or < 0 on error. 1777 */ 1778 int __audit_ipc_obj(struct kern_ipc_perm *ipcp) 1779 { 1780 struct audit_aux_data_ipcctl *ax; 1781 struct audit_context *context = current->audit_context; 1782 1783 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1784 if (!ax) 1785 return -ENOMEM; 1786 1787 ax->uid = ipcp->uid; 1788 ax->gid = ipcp->gid; 1789 ax->mode = ipcp->mode; 1790 selinux_get_ipc_sid(ipcp, &ax->osid); 1791 1792 ax->d.type = AUDIT_IPC; 1793 ax->d.next = context->aux; 1794 context->aux = (void *)ax; 1795 return 0; 1796 } 1797 1798 /** 1799 * audit_ipc_set_perm - record audit data for new ipc permissions 1800 * @qbytes: msgq bytes 1801 * @uid: msgq user id 1802 * @gid: msgq group id 1803 * @mode: msgq mode (permissions) 1804 * 1805 * Returns 0 for success or NULL context or < 0 on error. 1806 */ 1807 int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) 1808 { 1809 struct audit_aux_data_ipcctl *ax; 1810 struct audit_context *context = current->audit_context; 1811 1812 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1813 if (!ax) 1814 return -ENOMEM; 1815 1816 ax->qbytes = qbytes; 1817 ax->uid = uid; 1818 ax->gid = gid; 1819 ax->mode = mode; 1820 1821 ax->d.type = AUDIT_IPC_SET_PERM; 1822 ax->d.next = context->aux; 1823 context->aux = (void *)ax; 1824 return 0; 1825 } 1826 1827 int audit_bprm(struct linux_binprm *bprm) 1828 { 1829 struct audit_aux_data_execve *ax; 1830 struct audit_context *context = current->audit_context; 1831 unsigned long p, next; 1832 void *to; 1833 1834 if (likely(!audit_enabled || !context || context->dummy)) 1835 return 0; 1836 1837 ax = kmalloc(sizeof(*ax) + PAGE_SIZE * MAX_ARG_PAGES - bprm->p, 1838 GFP_KERNEL); 1839 if (!ax) 1840 return -ENOMEM; 1841 1842 ax->argc = bprm->argc; 1843 ax->envc = bprm->envc; 1844 for (p = bprm->p, to = ax->mem; p < MAX_ARG_PAGES*PAGE_SIZE; p = next) { 1845 struct page *page = bprm->page[p / PAGE_SIZE]; 1846 void *kaddr = kmap(page); 1847 next = (p + PAGE_SIZE) & ~(PAGE_SIZE - 1); 1848 memcpy(to, kaddr + (p & (PAGE_SIZE - 1)), next - p); 1849 to += next - p; 1850 kunmap(page); 1851 } 1852 1853 ax->d.type = AUDIT_EXECVE; 1854 ax->d.next = context->aux; 1855 context->aux = (void *)ax; 1856 return 0; 1857 } 1858 1859 1860 /** 1861 * audit_socketcall - record audit data for sys_socketcall 1862 * @nargs: number of args 1863 * @args: args array 1864 * 1865 * Returns 0 for success or NULL context or < 0 on error. 1866 */ 1867 int audit_socketcall(int nargs, unsigned long *args) 1868 { 1869 struct audit_aux_data_socketcall *ax; 1870 struct audit_context *context = current->audit_context; 1871 1872 if (likely(!context || context->dummy)) 1873 return 0; 1874 1875 ax = kmalloc(sizeof(*ax) + nargs * sizeof(unsigned long), GFP_KERNEL); 1876 if (!ax) 1877 return -ENOMEM; 1878 1879 ax->nargs = nargs; 1880 memcpy(ax->args, args, nargs * sizeof(unsigned long)); 1881 1882 ax->d.type = AUDIT_SOCKETCALL; 1883 ax->d.next = context->aux; 1884 context->aux = (void *)ax; 1885 return 0; 1886 } 1887 1888 /** 1889 * __audit_fd_pair - record audit data for pipe and socketpair 1890 * @fd1: the first file descriptor 1891 * @fd2: the second file descriptor 1892 * 1893 * Returns 0 for success or NULL context or < 0 on error. 1894 */ 1895 int __audit_fd_pair(int fd1, int fd2) 1896 { 1897 struct audit_context *context = current->audit_context; 1898 struct audit_aux_data_fd_pair *ax; 1899 1900 if (likely(!context)) { 1901 return 0; 1902 } 1903 1904 ax = kmalloc(sizeof(*ax), GFP_KERNEL); 1905 if (!ax) { 1906 return -ENOMEM; 1907 } 1908 1909 ax->fd[0] = fd1; 1910 ax->fd[1] = fd2; 1911 1912 ax->d.type = AUDIT_FD_PAIR; 1913 ax->d.next = context->aux; 1914 context->aux = (void *)ax; 1915 return 0; 1916 } 1917 1918 /** 1919 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto 1920 * @len: data length in user space 1921 * @a: data address in kernel space 1922 * 1923 * Returns 0 for success or NULL context or < 0 on error. 1924 */ 1925 int audit_sockaddr(int len, void *a) 1926 { 1927 struct audit_aux_data_sockaddr *ax; 1928 struct audit_context *context = current->audit_context; 1929 1930 if (likely(!context || context->dummy)) 1931 return 0; 1932 1933 ax = kmalloc(sizeof(*ax) + len, GFP_KERNEL); 1934 if (!ax) 1935 return -ENOMEM; 1936 1937 ax->len = len; 1938 memcpy(ax->a, a, len); 1939 1940 ax->d.type = AUDIT_SOCKADDR; 1941 ax->d.next = context->aux; 1942 context->aux = (void *)ax; 1943 return 0; 1944 } 1945 1946 void __audit_ptrace(struct task_struct *t) 1947 { 1948 struct audit_context *context = current->audit_context; 1949 1950 context->target_pid = t->pid; 1951 selinux_get_task_sid(t, &context->target_sid); 1952 } 1953 1954 /** 1955 * audit_avc_path - record the granting or denial of permissions 1956 * @dentry: dentry to record 1957 * @mnt: mnt to record 1958 * 1959 * Returns 0 for success or NULL context or < 0 on error. 1960 * 1961 * Called from security/selinux/avc.c::avc_audit() 1962 */ 1963 int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt) 1964 { 1965 struct audit_aux_data_path *ax; 1966 struct audit_context *context = current->audit_context; 1967 1968 if (likely(!context)) 1969 return 0; 1970 1971 ax = kmalloc(sizeof(*ax), GFP_ATOMIC); 1972 if (!ax) 1973 return -ENOMEM; 1974 1975 ax->dentry = dget(dentry); 1976 ax->mnt = mntget(mnt); 1977 1978 ax->d.type = AUDIT_AVC_PATH; 1979 ax->d.next = context->aux; 1980 context->aux = (void *)ax; 1981 return 0; 1982 } 1983 1984 /** 1985 * audit_signal_info - record signal info for shutting down audit subsystem 1986 * @sig: signal value 1987 * @t: task being signaled 1988 * 1989 * If the audit subsystem is being terminated, record the task (pid) 1990 * and uid that is doing that. 1991 */ 1992 int __audit_signal_info(int sig, struct task_struct *t) 1993 { 1994 struct audit_aux_data_pids *axp; 1995 struct task_struct *tsk = current; 1996 struct audit_context *ctx = tsk->audit_context; 1997 extern pid_t audit_sig_pid; 1998 extern uid_t audit_sig_uid; 1999 extern u32 audit_sig_sid; 2000 2001 if (audit_pid && t->tgid == audit_pid && 2002 (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1)) { 2003 audit_sig_pid = tsk->pid; 2004 if (ctx) 2005 audit_sig_uid = ctx->loginuid; 2006 else 2007 audit_sig_uid = tsk->uid; 2008 selinux_get_task_sid(tsk, &audit_sig_sid); 2009 } 2010 2011 if (!audit_signals) /* audit_context checked in wrapper */ 2012 return 0; 2013 2014 /* optimize the common case by putting first signal recipient directly 2015 * in audit_context */ 2016 if (!ctx->target_pid) { 2017 ctx->target_pid = t->tgid; 2018 selinux_get_task_sid(t, &ctx->target_sid); 2019 return 0; 2020 } 2021 2022 axp = (void *)ctx->aux_pids; 2023 if (!axp || axp->pid_count == AUDIT_AUX_PIDS) { 2024 axp = kzalloc(sizeof(*axp), GFP_ATOMIC); 2025 if (!axp) 2026 return -ENOMEM; 2027 2028 axp->d.type = AUDIT_OBJ_PID; 2029 axp->d.next = ctx->aux_pids; 2030 ctx->aux_pids = (void *)axp; 2031 } 2032 BUG_ON(axp->pid_count > AUDIT_AUX_PIDS); 2033 2034 axp->target_pid[axp->pid_count] = t->tgid; 2035 selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]); 2036 axp->pid_count++; 2037 2038 return 0; 2039 } 2040 2041 /** 2042 * audit_core_dumps - record information about processes that end abnormally 2043 * @sig: signal value 2044 * 2045 * If a process ends with a core dump, something fishy is going on and we 2046 * should record the event for investigation. 2047 */ 2048 void audit_core_dumps(long signr) 2049 { 2050 struct audit_buffer *ab; 2051 u32 sid; 2052 2053 if (!audit_enabled) 2054 return; 2055 2056 if (signr == SIGQUIT) /* don't care for those */ 2057 return; 2058 2059 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); 2060 audit_log_format(ab, "auid=%u uid=%u gid=%u", 2061 audit_get_loginuid(current->audit_context), 2062 current->uid, current->gid); 2063 selinux_get_task_sid(current, &sid); 2064 if (sid) { 2065 char *ctx = NULL; 2066 u32 len; 2067 2068 if (selinux_sid_to_string(sid, &ctx, &len)) 2069 audit_log_format(ab, " ssid=%u", sid); 2070 else 2071 audit_log_format(ab, " subj=%s", ctx); 2072 kfree(ctx); 2073 } 2074 audit_log_format(ab, " pid=%d comm=", current->pid); 2075 audit_log_untrustedstring(ab, current->comm); 2076 audit_log_format(ab, " sig=%ld", signr); 2077 audit_log_end(ab); 2078 } 2079