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v5.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * AppArmor security module
   4 *
   5 * This file contains AppArmor LSM hooks.
   6 *
   7 * Copyright (C) 1998-2008 Novell/SUSE
   8 * Copyright 2009-2010 Canonical Ltd.
   9 */
  10
  11#include <linux/lsm_hooks.h>
  12#include <linux/moduleparam.h>
  13#include <linux/mm.h>
  14#include <linux/mman.h>
  15#include <linux/mount.h>
  16#include <linux/namei.h>
  17#include <linux/ptrace.h>
  18#include <linux/ctype.h>
  19#include <linux/sysctl.h>
  20#include <linux/audit.h>
  21#include <linux/user_namespace.h>
  22#include <linux/netfilter_ipv4.h>
  23#include <linux/netfilter_ipv6.h>
 
  24#include <net/sock.h>
  25#include <uapi/linux/mount.h>
  26
  27#include "include/apparmor.h"
  28#include "include/apparmorfs.h"
  29#include "include/audit.h"
  30#include "include/capability.h"
  31#include "include/cred.h"
  32#include "include/file.h"
  33#include "include/ipc.h"
  34#include "include/net.h"
  35#include "include/path.h"
  36#include "include/label.h"
  37#include "include/policy.h"
  38#include "include/policy_ns.h"
  39#include "include/procattr.h"
  40#include "include/mount.h"
  41#include "include/secid.h"
  42
  43/* Flag indicating whether initialization completed */
  44int apparmor_initialized;
  45
  46DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
 
 
 
 
 
 
 
  47
 
 
  48
  49/*
  50 * LSM hook functions
  51 */
  52
  53/*
  54 * put the associated labels
  55 */
  56static void apparmor_cred_free(struct cred *cred)
  57{
  58	aa_put_label(cred_label(cred));
  59	set_cred_label(cred, NULL);
  60}
  61
  62/*
  63 * allocate the apparmor part of blank credentials
  64 */
  65static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
  66{
  67	set_cred_label(cred, NULL);
  68	return 0;
  69}
  70
  71/*
  72 * prepare new cred label for modification by prepare_cred block
  73 */
  74static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
  75				 gfp_t gfp)
  76{
  77	set_cred_label(new, aa_get_newest_label(cred_label(old)));
  78	return 0;
  79}
  80
  81/*
  82 * transfer the apparmor data to a blank set of creds
  83 */
  84static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
  85{
  86	set_cred_label(new, aa_get_newest_label(cred_label(old)));
  87}
  88
  89static void apparmor_task_free(struct task_struct *task)
  90{
  91
  92	aa_free_task_ctx(task_ctx(task));
  93}
  94
  95static int apparmor_task_alloc(struct task_struct *task,
  96			       unsigned long clone_flags)
  97{
  98	struct aa_task_ctx *new = task_ctx(task);
  99
 100	aa_dup_task_ctx(new, task_ctx(current));
 101
 102	return 0;
 103}
 104
 105static int apparmor_ptrace_access_check(struct task_struct *child,
 106					unsigned int mode)
 107{
 108	struct aa_label *tracer, *tracee;
 109	int error;
 110
 111	tracer = __begin_current_label_crit_section();
 112	tracee = aa_get_task_label(child);
 113	error = aa_may_ptrace(tracer, tracee,
 114			(mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
 115						  : AA_PTRACE_TRACE);
 116	aa_put_label(tracee);
 117	__end_current_label_crit_section(tracer);
 118
 119	return error;
 120}
 121
 122static int apparmor_ptrace_traceme(struct task_struct *parent)
 123{
 124	struct aa_label *tracer, *tracee;
 125	int error;
 126
 127	tracee = __begin_current_label_crit_section();
 128	tracer = aa_get_task_label(parent);
 129	error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
 130	aa_put_label(tracer);
 131	__end_current_label_crit_section(tracee);
 132
 133	return error;
 134}
 135
 136/* Derived from security/commoncap.c:cap_capget */
 137static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
 138			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
 139{
 140	struct aa_label *label;
 141	const struct cred *cred;
 142
 143	rcu_read_lock();
 144	cred = __task_cred(target);
 145	label = aa_get_newest_cred_label(cred);
 146
 147	/*
 148	 * cap_capget is stacked ahead of this and will
 149	 * initialize effective and permitted.
 150	 */
 151	if (!unconfined(label)) {
 152		struct aa_profile *profile;
 153		struct label_it i;
 154
 155		label_for_each_confined(i, label, profile) {
 156			if (COMPLAIN_MODE(profile))
 157				continue;
 158			*effective = cap_intersect(*effective,
 159						   profile->caps.allow);
 160			*permitted = cap_intersect(*permitted,
 161						   profile->caps.allow);
 162		}
 163	}
 164	rcu_read_unlock();
 165	aa_put_label(label);
 166
 167	return 0;
 168}
 169
 170static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
 171			    int cap, unsigned int opts)
 172{
 173	struct aa_label *label;
 174	int error = 0;
 175
 176	label = aa_get_newest_cred_label(cred);
 177	if (!unconfined(label))
 178		error = aa_capable(label, cap, opts);
 179	aa_put_label(label);
 180
 181	return error;
 182}
 183
 184/**
 185 * common_perm - basic common permission check wrapper fn for paths
 186 * @op: operation being checked
 187 * @path: path to check permission of  (NOT NULL)
 188 * @mask: requested permissions mask
 189 * @cond: conditional info for the permission request  (NOT NULL)
 190 *
 191 * Returns: %0 else error code if error or permission denied
 192 */
 193static int common_perm(const char *op, const struct path *path, u32 mask,
 194		       struct path_cond *cond)
 195{
 196	struct aa_label *label;
 197	int error = 0;
 198
 199	label = __begin_current_label_crit_section();
 200	if (!unconfined(label))
 201		error = aa_path_perm(op, label, path, 0, mask, cond);
 202	__end_current_label_crit_section(label);
 203
 204	return error;
 205}
 206
 207/**
 208 * common_perm_cond - common permission wrapper around inode cond
 209 * @op: operation being checked
 210 * @path: location to check (NOT NULL)
 211 * @mask: requested permissions mask
 212 *
 213 * Returns: %0 else error code if error or permission denied
 214 */
 215static int common_perm_cond(const char *op, const struct path *path, u32 mask)
 216{
 217	struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
 218				  d_backing_inode(path->dentry)->i_mode
 
 
 219	};
 220
 221	if (!path_mediated_fs(path->dentry))
 222		return 0;
 223
 224	return common_perm(op, path, mask, &cond);
 225}
 226
 227/**
 228 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
 229 * @op: operation being checked
 230 * @dir: directory of the dentry  (NOT NULL)
 231 * @dentry: dentry to check  (NOT NULL)
 232 * @mask: requested permissions mask
 233 * @cond: conditional info for the permission request  (NOT NULL)
 234 *
 235 * Returns: %0 else error code if error or permission denied
 236 */
 237static int common_perm_dir_dentry(const char *op, const struct path *dir,
 238				  struct dentry *dentry, u32 mask,
 239				  struct path_cond *cond)
 240{
 241	struct path path = { .mnt = dir->mnt, .dentry = dentry };
 242
 243	return common_perm(op, &path, mask, cond);
 244}
 245
 246/**
 247 * common_perm_rm - common permission wrapper for operations doing rm
 248 * @op: operation being checked
 249 * @dir: directory that the dentry is in  (NOT NULL)
 250 * @dentry: dentry being rm'd  (NOT NULL)
 251 * @mask: requested permission mask
 252 *
 253 * Returns: %0 else error code if error or permission denied
 254 */
 255static int common_perm_rm(const char *op, const struct path *dir,
 256			  struct dentry *dentry, u32 mask)
 257{
 258	struct inode *inode = d_backing_inode(dentry);
 
 259	struct path_cond cond = { };
 260
 261	if (!inode || !path_mediated_fs(dentry))
 262		return 0;
 263
 264	cond.uid = inode->i_uid;
 265	cond.mode = inode->i_mode;
 266
 267	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
 268}
 269
 270/**
 271 * common_perm_create - common permission wrapper for operations doing create
 272 * @op: operation being checked
 273 * @dir: directory that dentry will be created in  (NOT NULL)
 274 * @dentry: dentry to create   (NOT NULL)
 275 * @mask: request permission mask
 276 * @mode: created file mode
 277 *
 278 * Returns: %0 else error code if error or permission denied
 279 */
 280static int common_perm_create(const char *op, const struct path *dir,
 281			      struct dentry *dentry, u32 mask, umode_t mode)
 282{
 283	struct path_cond cond = { current_fsuid(), mode };
 284
 285	if (!path_mediated_fs(dir->dentry))
 286		return 0;
 287
 288	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
 289}
 290
 291static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
 292{
 293	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
 294}
 295
 296static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
 297			       umode_t mode)
 298{
 299	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
 300				  S_IFDIR);
 301}
 302
 303static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
 304{
 305	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
 306}
 307
 308static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
 309			       umode_t mode, unsigned int dev)
 310{
 311	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
 312}
 313
 314static int apparmor_path_truncate(const struct path *path)
 315{
 316	return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
 317}
 318
 319static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
 320				 const char *old_name)
 321{
 322	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
 323				  S_IFLNK);
 324}
 325
 326static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
 327			      struct dentry *new_dentry)
 328{
 329	struct aa_label *label;
 330	int error = 0;
 331
 332	if (!path_mediated_fs(old_dentry))
 333		return 0;
 334
 335	label = begin_current_label_crit_section();
 336	if (!unconfined(label))
 337		error = aa_path_link(label, old_dentry, new_dir, new_dentry);
 338	end_current_label_crit_section(label);
 339
 340	return error;
 341}
 342
 343static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
 344				const struct path *new_dir, struct dentry *new_dentry)
 345{
 346	struct aa_label *label;
 347	int error = 0;
 348
 349	if (!path_mediated_fs(old_dentry))
 350		return 0;
 351
 352	label = begin_current_label_crit_section();
 353	if (!unconfined(label)) {
 
 354		struct path old_path = { .mnt = old_dir->mnt,
 355					 .dentry = old_dentry };
 356		struct path new_path = { .mnt = new_dir->mnt,
 357					 .dentry = new_dentry };
 358		struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
 359					  d_backing_inode(old_dentry)->i_mode
 
 360		};
 361
 362		error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
 363				     MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
 364				     AA_MAY_SETATTR | AA_MAY_DELETE,
 365				     &cond);
 366		if (!error)
 367			error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
 368					     0, MAY_WRITE | AA_MAY_SETATTR |
 369					     AA_MAY_CREATE, &cond);
 370
 371	}
 372	end_current_label_crit_section(label);
 373
 374	return error;
 375}
 376
 377static int apparmor_path_chmod(const struct path *path, umode_t mode)
 378{
 379	return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
 380}
 381
 382static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
 383{
 384	return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
 385}
 386
 387static int apparmor_inode_getattr(const struct path *path)
 388{
 389	return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
 390}
 391
 392static int apparmor_file_open(struct file *file)
 393{
 394	struct aa_file_ctx *fctx = file_ctx(file);
 395	struct aa_label *label;
 396	int error = 0;
 397
 398	if (!path_mediated_fs(file->f_path.dentry))
 399		return 0;
 400
 401	/* If in exec, permission is handled by bprm hooks.
 402	 * Cache permissions granted by the previous exec check, with
 403	 * implicit read and executable mmap which are required to
 404	 * actually execute the image.
 405	 */
 406	if (current->in_execve) {
 407		fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
 408		return 0;
 409	}
 410
 411	label = aa_get_newest_cred_label(file->f_cred);
 412	if (!unconfined(label)) {
 
 413		struct inode *inode = file_inode(file);
 414		struct path_cond cond = { inode->i_uid, inode->i_mode };
 
 
 
 415
 416		error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
 417				     aa_map_file_to_perms(file), &cond);
 418		/* todo cache full allowed permissions set and state */
 419		fctx->allow = aa_map_file_to_perms(file);
 420	}
 421	aa_put_label(label);
 422
 423	return error;
 424}
 425
 426static int apparmor_file_alloc_security(struct file *file)
 427{
 428	struct aa_file_ctx *ctx = file_ctx(file);
 429	struct aa_label *label = begin_current_label_crit_section();
 430
 431	spin_lock_init(&ctx->lock);
 432	rcu_assign_pointer(ctx->label, aa_get_label(label));
 433	end_current_label_crit_section(label);
 434	return 0;
 435}
 436
 437static void apparmor_file_free_security(struct file *file)
 438{
 439	struct aa_file_ctx *ctx = file_ctx(file);
 440
 441	if (ctx)
 442		aa_put_label(rcu_access_pointer(ctx->label));
 443}
 444
 445static int common_file_perm(const char *op, struct file *file, u32 mask)
 
 446{
 447	struct aa_label *label;
 448	int error = 0;
 449
 450	/* don't reaudit files closed during inheritance */
 451	if (file->f_path.dentry == aa_null.dentry)
 452		return -EACCES;
 453
 454	label = __begin_current_label_crit_section();
 455	error = aa_file_perm(op, label, file, mask);
 456	__end_current_label_crit_section(label);
 457
 458	return error;
 459}
 460
 461static int apparmor_file_receive(struct file *file)
 462{
 463	return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
 
 464}
 465
 466static int apparmor_file_permission(struct file *file, int mask)
 467{
 468	return common_file_perm(OP_FPERM, file, mask);
 469}
 470
 471static int apparmor_file_lock(struct file *file, unsigned int cmd)
 472{
 473	u32 mask = AA_MAY_LOCK;
 474
 475	if (cmd == F_WRLCK)
 476		mask |= MAY_WRITE;
 477
 478	return common_file_perm(OP_FLOCK, file, mask);
 479}
 480
 481static int common_mmap(const char *op, struct file *file, unsigned long prot,
 482		       unsigned long flags)
 483{
 484	int mask = 0;
 485
 486	if (!file || !file_ctx(file))
 487		return 0;
 488
 489	if (prot & PROT_READ)
 490		mask |= MAY_READ;
 491	/*
 492	 * Private mappings don't require write perms since they don't
 493	 * write back to the files
 494	 */
 495	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
 496		mask |= MAY_WRITE;
 497	if (prot & PROT_EXEC)
 498		mask |= AA_EXEC_MMAP;
 499
 500	return common_file_perm(op, file, mask);
 501}
 502
 503static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
 504			      unsigned long prot, unsigned long flags)
 505{
 506	return common_mmap(OP_FMMAP, file, prot, flags);
 507}
 508
 509static int apparmor_file_mprotect(struct vm_area_struct *vma,
 510				  unsigned long reqprot, unsigned long prot)
 511{
 512	return common_mmap(OP_FMPROT, vma->vm_file, prot,
 513			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
 
 514}
 515
 516static int apparmor_sb_mount(const char *dev_name, const struct path *path,
 517			     const char *type, unsigned long flags, void *data)
 518{
 519	struct aa_label *label;
 520	int error = 0;
 521
 522	/* Discard magic */
 523	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
 524		flags &= ~MS_MGC_MSK;
 525
 526	flags &= ~AA_MS_IGNORE_MASK;
 527
 528	label = __begin_current_label_crit_section();
 529	if (!unconfined(label)) {
 530		if (flags & MS_REMOUNT)
 531			error = aa_remount(label, path, flags, data);
 532		else if (flags & MS_BIND)
 533			error = aa_bind_mount(label, path, dev_name, flags);
 534		else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
 535				  MS_UNBINDABLE))
 536			error = aa_mount_change_type(label, path, flags);
 537		else if (flags & MS_MOVE)
 538			error = aa_move_mount(label, path, dev_name);
 539		else
 540			error = aa_new_mount(label, dev_name, path, type,
 541					     flags, data);
 542	}
 543	__end_current_label_crit_section(label);
 544
 545	return error;
 546}
 547
 548static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
 549{
 550	struct aa_label *label;
 551	int error = 0;
 552
 553	label = __begin_current_label_crit_section();
 554	if (!unconfined(label))
 555		error = aa_umount(label, mnt, flags);
 556	__end_current_label_crit_section(label);
 557
 558	return error;
 559}
 560
 561static int apparmor_sb_pivotroot(const struct path *old_path,
 562				 const struct path *new_path)
 563{
 564	struct aa_label *label;
 565	int error = 0;
 566
 567	label = aa_get_current_label();
 568	if (!unconfined(label))
 569		error = aa_pivotroot(label, old_path, new_path);
 570	aa_put_label(label);
 571
 572	return error;
 573}
 574
 575static int apparmor_getprocattr(struct task_struct *task, char *name,
 576				char **value)
 577{
 578	int error = -ENOENT;
 579	/* released below */
 580	const struct cred *cred = get_task_cred(task);
 581	struct aa_task_ctx *ctx = task_ctx(current);
 582	struct aa_label *label = NULL;
 583
 584	if (strcmp(name, "current") == 0)
 585		label = aa_get_newest_label(cred_label(cred));
 586	else if (strcmp(name, "prev") == 0  && ctx->previous)
 587		label = aa_get_newest_label(ctx->previous);
 588	else if (strcmp(name, "exec") == 0 && ctx->onexec)
 589		label = aa_get_newest_label(ctx->onexec);
 590	else
 591		error = -EINVAL;
 592
 593	if (label)
 594		error = aa_getprocattr(label, value);
 595
 596	aa_put_label(label);
 597	put_cred(cred);
 598
 599	return error;
 600}
 601
 602static int apparmor_setprocattr(const char *name, void *value,
 603				size_t size)
 604{
 605	char *command, *largs = NULL, *args = value;
 606	size_t arg_size;
 607	int error;
 608	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
 609
 610	if (size == 0)
 611		return -EINVAL;
 612
 613	/* AppArmor requires that the buffer must be null terminated atm */
 614	if (args[size - 1] != '\0') {
 615		/* null terminate */
 616		largs = args = kmalloc(size + 1, GFP_KERNEL);
 617		if (!args)
 618			return -ENOMEM;
 619		memcpy(args, value, size);
 620		args[size] = '\0';
 621	}
 622
 623	error = -EINVAL;
 624	args = strim(args);
 625	command = strsep(&args, " ");
 626	if (!args)
 627		goto out;
 628	args = skip_spaces(args);
 629	if (!*args)
 630		goto out;
 631
 632	arg_size = size - (args - (largs ? largs : (char *) value));
 633	if (strcmp(name, "current") == 0) {
 634		if (strcmp(command, "changehat") == 0) {
 635			error = aa_setprocattr_changehat(args, arg_size,
 636							 AA_CHANGE_NOFLAGS);
 637		} else if (strcmp(command, "permhat") == 0) {
 638			error = aa_setprocattr_changehat(args, arg_size,
 639							 AA_CHANGE_TEST);
 640		} else if (strcmp(command, "changeprofile") == 0) {
 641			error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
 642		} else if (strcmp(command, "permprofile") == 0) {
 643			error = aa_change_profile(args, AA_CHANGE_TEST);
 644		} else if (strcmp(command, "stack") == 0) {
 645			error = aa_change_profile(args, AA_CHANGE_STACK);
 646		} else
 647			goto fail;
 648	} else if (strcmp(name, "exec") == 0) {
 649		if (strcmp(command, "exec") == 0)
 650			error = aa_change_profile(args, AA_CHANGE_ONEXEC);
 651		else if (strcmp(command, "stack") == 0)
 652			error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
 653							 AA_CHANGE_STACK));
 654		else
 655			goto fail;
 656	} else
 657		/* only support the "current" and "exec" process attributes */
 658		goto fail;
 659
 660	if (!error)
 661		error = size;
 662out:
 663	kfree(largs);
 664	return error;
 665
 666fail:
 667	aad(&sa)->label = begin_current_label_crit_section();
 668	aad(&sa)->info = name;
 669	aad(&sa)->error = error = -EINVAL;
 670	aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
 671	end_current_label_crit_section(aad(&sa)->label);
 672	goto out;
 673}
 674
 675/**
 676 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
 677 * @bprm: binprm for the exec  (NOT NULL)
 678 */
 679static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
 680{
 681	struct aa_label *label = aa_current_raw_label();
 682	struct aa_label *new_label = cred_label(bprm->cred);
 683
 684	/* bail out if unconfined or not changing profile */
 685	if ((new_label->proxy == label->proxy) ||
 686	    (unconfined(new_label)))
 687		return;
 688
 689	aa_inherit_files(bprm->cred, current->files);
 690
 691	current->pdeath_signal = 0;
 692
 693	/* reset soft limits and set hard limits for the new label */
 694	__aa_transition_rlimits(label, new_label);
 695}
 696
 697/**
 698 * apparmor_bprm_committed_cred - do cleanup after new creds committed
 699 * @bprm: binprm for the exec  (NOT NULL)
 700 */
 701static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
 702{
 703	/* clear out temporary/transitional state from the context */
 704	aa_clear_task_ctx_trans(task_ctx(current));
 705
 706	return;
 707}
 708
 709static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
 710{
 711	struct aa_label *label = aa_get_task_label(p);
 712	*secid = label->secid;
 713	aa_put_label(label);
 714}
 715
 716static int apparmor_task_setrlimit(struct task_struct *task,
 717		unsigned int resource, struct rlimit *new_rlim)
 718{
 719	struct aa_label *label = __begin_current_label_crit_section();
 720	int error = 0;
 721
 722	if (!unconfined(label))
 723		error = aa_task_setrlimit(label, task, resource, new_rlim);
 724	__end_current_label_crit_section(label);
 725
 726	return error;
 727}
 728
 729static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
 730			      int sig, const struct cred *cred)
 731{
 732	struct aa_label *cl, *tl;
 733	int error;
 734
 735	if (cred) {
 736		/*
 737		 * Dealing with USB IO specific behavior
 738		 */
 739		cl = aa_get_newest_cred_label(cred);
 740		tl = aa_get_task_label(target);
 741		error = aa_may_signal(cl, tl, sig);
 742		aa_put_label(cl);
 743		aa_put_label(tl);
 744		return error;
 745	}
 746
 747	cl = __begin_current_label_crit_section();
 748	tl = aa_get_task_label(target);
 749	error = aa_may_signal(cl, tl, sig);
 750	aa_put_label(tl);
 751	__end_current_label_crit_section(cl);
 752
 753	return error;
 754}
 755
 756/**
 757 * apparmor_sk_alloc_security - allocate and attach the sk_security field
 758 */
 759static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
 760{
 761	struct aa_sk_ctx *ctx;
 762
 763	ctx = kzalloc(sizeof(*ctx), flags);
 764	if (!ctx)
 765		return -ENOMEM;
 766
 767	SK_CTX(sk) = ctx;
 768
 769	return 0;
 770}
 771
 772/**
 773 * apparmor_sk_free_security - free the sk_security field
 774 */
 775static void apparmor_sk_free_security(struct sock *sk)
 776{
 777	struct aa_sk_ctx *ctx = SK_CTX(sk);
 778
 779	SK_CTX(sk) = NULL;
 780	aa_put_label(ctx->label);
 781	aa_put_label(ctx->peer);
 782	kfree(ctx);
 783}
 784
 785/**
 786 * apparmor_clone_security - clone the sk_security field
 787 */
 788static void apparmor_sk_clone_security(const struct sock *sk,
 789				       struct sock *newsk)
 790{
 791	struct aa_sk_ctx *ctx = SK_CTX(sk);
 792	struct aa_sk_ctx *new = SK_CTX(newsk);
 793
 
 
 794	new->label = aa_get_label(ctx->label);
 
 
 
 795	new->peer = aa_get_label(ctx->peer);
 796}
 797
 798/**
 799 * apparmor_socket_create - check perms before creating a new socket
 800 */
 801static int apparmor_socket_create(int family, int type, int protocol, int kern)
 802{
 803	struct aa_label *label;
 804	int error = 0;
 805
 806	AA_BUG(in_interrupt());
 807
 808	label = begin_current_label_crit_section();
 809	if (!(kern || unconfined(label)))
 810		error = af_select(family,
 811				  create_perm(label, family, type, protocol),
 812				  aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
 813					     family, type, protocol));
 814	end_current_label_crit_section(label);
 815
 816	return error;
 817}
 818
 819/**
 820 * apparmor_socket_post_create - setup the per-socket security struct
 821 *
 822 * Note:
 823 * -   kernel sockets currently labeled unconfined but we may want to
 824 *     move to a special kernel label
 825 * -   socket may not have sk here if created with sock_create_lite or
 826 *     sock_alloc. These should be accept cases which will be handled in
 827 *     sock_graft.
 828 */
 829static int apparmor_socket_post_create(struct socket *sock, int family,
 830				       int type, int protocol, int kern)
 831{
 832	struct aa_label *label;
 833
 834	if (kern) {
 835		struct aa_ns *ns = aa_get_current_ns();
 836
 837		label = aa_get_label(ns_unconfined(ns));
 838		aa_put_ns(ns);
 839	} else
 840		label = aa_get_current_label();
 841
 842	if (sock->sk) {
 843		struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
 844
 845		aa_put_label(ctx->label);
 846		ctx->label = aa_get_label(label);
 847	}
 848	aa_put_label(label);
 849
 850	return 0;
 851}
 852
 853/**
 854 * apparmor_socket_bind - check perms before bind addr to socket
 855 */
 856static int apparmor_socket_bind(struct socket *sock,
 857				struct sockaddr *address, int addrlen)
 858{
 859	AA_BUG(!sock);
 860	AA_BUG(!sock->sk);
 861	AA_BUG(!address);
 862	AA_BUG(in_interrupt());
 863
 864	return af_select(sock->sk->sk_family,
 865			 bind_perm(sock, address, addrlen),
 866			 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
 867}
 868
 869/**
 870 * apparmor_socket_connect - check perms before connecting @sock to @address
 871 */
 872static int apparmor_socket_connect(struct socket *sock,
 873				   struct sockaddr *address, int addrlen)
 874{
 875	AA_BUG(!sock);
 876	AA_BUG(!sock->sk);
 877	AA_BUG(!address);
 878	AA_BUG(in_interrupt());
 879
 880	return af_select(sock->sk->sk_family,
 881			 connect_perm(sock, address, addrlen),
 882			 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
 883}
 884
 885/**
 886 * apparmor_socket_list - check perms before allowing listen
 887 */
 888static int apparmor_socket_listen(struct socket *sock, int backlog)
 889{
 890	AA_BUG(!sock);
 891	AA_BUG(!sock->sk);
 892	AA_BUG(in_interrupt());
 893
 894	return af_select(sock->sk->sk_family,
 895			 listen_perm(sock, backlog),
 896			 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
 897}
 898
 899/**
 900 * apparmor_socket_accept - check perms before accepting a new connection.
 901 *
 902 * Note: while @newsock is created and has some information, the accept
 903 *       has not been done.
 904 */
 905static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
 906{
 907	AA_BUG(!sock);
 908	AA_BUG(!sock->sk);
 909	AA_BUG(!newsock);
 910	AA_BUG(in_interrupt());
 911
 912	return af_select(sock->sk->sk_family,
 913			 accept_perm(sock, newsock),
 914			 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
 915}
 916
 917static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
 918			    struct msghdr *msg, int size)
 919{
 920	AA_BUG(!sock);
 921	AA_BUG(!sock->sk);
 922	AA_BUG(!msg);
 923	AA_BUG(in_interrupt());
 924
 925	return af_select(sock->sk->sk_family,
 926			 msg_perm(op, request, sock, msg, size),
 927			 aa_sk_perm(op, request, sock->sk));
 928}
 929
 930/**
 931 * apparmor_socket_sendmsg - check perms before sending msg to another socket
 932 */
 933static int apparmor_socket_sendmsg(struct socket *sock,
 934				   struct msghdr *msg, int size)
 935{
 936	return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
 937}
 938
 939/**
 940 * apparmor_socket_recvmsg - check perms before receiving a message
 941 */
 942static int apparmor_socket_recvmsg(struct socket *sock,
 943				   struct msghdr *msg, int size, int flags)
 944{
 945	return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
 946}
 947
 948/* revaliation, get/set attr, shutdown */
 949static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
 950{
 951	AA_BUG(!sock);
 952	AA_BUG(!sock->sk);
 953	AA_BUG(in_interrupt());
 954
 955	return af_select(sock->sk->sk_family,
 956			 sock_perm(op, request, sock),
 957			 aa_sk_perm(op, request, sock->sk));
 958}
 959
 960/**
 961 * apparmor_socket_getsockname - check perms before getting the local address
 962 */
 963static int apparmor_socket_getsockname(struct socket *sock)
 964{
 965	return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
 966}
 967
 968/**
 969 * apparmor_socket_getpeername - check perms before getting remote address
 970 */
 971static int apparmor_socket_getpeername(struct socket *sock)
 972{
 973	return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
 974}
 975
 976/* revaliation, get/set attr, opt */
 977static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
 978			    int level, int optname)
 979{
 980	AA_BUG(!sock);
 981	AA_BUG(!sock->sk);
 982	AA_BUG(in_interrupt());
 983
 984	return af_select(sock->sk->sk_family,
 985			 opt_perm(op, request, sock, level, optname),
 986			 aa_sk_perm(op, request, sock->sk));
 987}
 988
 989/**
 990 * apparmor_getsockopt - check perms before getting socket options
 991 */
 992static int apparmor_socket_getsockopt(struct socket *sock, int level,
 993				      int optname)
 994{
 995	return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
 996				level, optname);
 997}
 998
 999/**
1000 * apparmor_setsockopt - check perms before setting socket options
1001 */
1002static int apparmor_socket_setsockopt(struct socket *sock, int level,
1003				      int optname)
1004{
1005	return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1006				level, optname);
1007}
1008
1009/**
1010 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1011 */
1012static int apparmor_socket_shutdown(struct socket *sock, int how)
1013{
1014	return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1015}
1016
1017#ifdef CONFIG_NETWORK_SECMARK
1018/**
1019 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1020 *
1021 * Note: can not sleep may be called with locks held
1022 *
1023 * dont want protocol specific in __skb_recv_datagram()
1024 * to deny an incoming connection  socket_sock_rcv_skb()
1025 */
1026static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1027{
1028	struct aa_sk_ctx *ctx = SK_CTX(sk);
1029
1030	if (!skb->secmark)
1031		return 0;
1032
1033	return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1034				      skb->secmark, sk);
1035}
1036#endif
1037
1038
1039static struct aa_label *sk_peer_label(struct sock *sk)
1040{
1041	struct aa_sk_ctx *ctx = SK_CTX(sk);
1042
1043	if (ctx->peer)
1044		return ctx->peer;
1045
1046	return ERR_PTR(-ENOPROTOOPT);
1047}
1048
1049/**
1050 * apparmor_socket_getpeersec_stream - get security context of peer
1051 *
1052 * Note: for tcp only valid if using ipsec or cipso on lan
1053 */
1054static int apparmor_socket_getpeersec_stream(struct socket *sock,
1055					     char __user *optval,
1056					     int __user *optlen,
1057					     unsigned int len)
1058{
1059	char *name;
1060	int slen, error = 0;
1061	struct aa_label *label;
1062	struct aa_label *peer;
1063
1064	label = begin_current_label_crit_section();
1065	peer = sk_peer_label(sock->sk);
1066	if (IS_ERR(peer)) {
1067		error = PTR_ERR(peer);
1068		goto done;
1069	}
1070	slen = aa_label_asxprint(&name, labels_ns(label), peer,
1071				 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1072				 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1073	/* don't include terminating \0 in slen, it breaks some apps */
1074	if (slen < 0) {
1075		error = -ENOMEM;
1076	} else {
1077		if (slen > len) {
1078			error = -ERANGE;
1079		} else if (copy_to_user(optval, name, slen)) {
1080			error = -EFAULT;
1081			goto out;
1082		}
1083		if (put_user(slen, optlen))
1084			error = -EFAULT;
1085out:
1086		kfree(name);
1087
1088	}
1089
1090done:
1091	end_current_label_crit_section(label);
1092
1093	return error;
1094}
1095
1096/**
1097 * apparmor_socket_getpeersec_dgram - get security label of packet
1098 * @sock: the peer socket
1099 * @skb: packet data
1100 * @secid: pointer to where to put the secid of the packet
1101 *
1102 * Sets the netlabel socket state on sk from parent
1103 */
1104static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1105					    struct sk_buff *skb, u32 *secid)
1106
1107{
1108	/* TODO: requires secid support */
1109	return -ENOPROTOOPT;
1110}
1111
1112/**
1113 * apparmor_sock_graft - Initialize newly created socket
1114 * @sk: child sock
1115 * @parent: parent socket
1116 *
1117 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1118 *       just set sk security information off of current creating process label
1119 *       Labeling of sk for accept case - probably should be sock based
1120 *       instead of task, because of the case where an implicitly labeled
1121 *       socket is shared by different tasks.
1122 */
1123static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1124{
1125	struct aa_sk_ctx *ctx = SK_CTX(sk);
1126
1127	if (!ctx->label)
1128		ctx->label = aa_get_current_label();
1129}
1130
1131#ifdef CONFIG_NETWORK_SECMARK
1132static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
1133				      struct request_sock *req)
1134{
1135	struct aa_sk_ctx *ctx = SK_CTX(sk);
1136
1137	if (!skb->secmark)
1138		return 0;
1139
1140	return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1141				      skb->secmark, sk);
1142}
1143#endif
1144
1145/*
1146 * The cred blob is a pointer to, not an instance of, an aa_task_ctx.
1147 */
1148struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
1149	.lbs_cred = sizeof(struct aa_task_ctx *),
1150	.lbs_file = sizeof(struct aa_file_ctx),
1151	.lbs_task = sizeof(struct aa_task_ctx),
1152};
1153
1154static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1155	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1156	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1157	LSM_HOOK_INIT(capget, apparmor_capget),
1158	LSM_HOOK_INIT(capable, apparmor_capable),
1159
1160	LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1161	LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1162	LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1163
1164	LSM_HOOK_INIT(path_link, apparmor_path_link),
1165	LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1166	LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1167	LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1168	LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1169	LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1170	LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1171	LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1172	LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1173	LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1174	LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1175
1176	LSM_HOOK_INIT(file_open, apparmor_file_open),
1177	LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1178	LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1179	LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1180	LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1181	LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1182	LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1183	LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1184
1185	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1186	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1187
1188	LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1189	LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1190	LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1191
1192	LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1193	LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1194	LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1195	LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1196	LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1197	LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1198	LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1199	LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1200	LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1201	LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1202	LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1203	LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1204	LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1205#ifdef CONFIG_NETWORK_SECMARK
1206	LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1207#endif
1208	LSM_HOOK_INIT(socket_getpeersec_stream,
1209		      apparmor_socket_getpeersec_stream),
1210	LSM_HOOK_INIT(socket_getpeersec_dgram,
1211		      apparmor_socket_getpeersec_dgram),
1212	LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1213#ifdef CONFIG_NETWORK_SECMARK
1214	LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1215#endif
1216
1217	LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1218	LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1219	LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1220	LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1221
1222	LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
1223	LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1224	LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1225
1226	LSM_HOOK_INIT(task_free, apparmor_task_free),
1227	LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1228	LSM_HOOK_INIT(task_getsecid, apparmor_task_getsecid),
 
1229	LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1230	LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1231
1232#ifdef CONFIG_AUDIT
1233	LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1234	LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1235	LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1236	LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1237#endif
1238
1239	LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1240	LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1241	LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1242};
1243
1244/*
1245 * AppArmor sysfs module parameters
1246 */
1247
1248static int param_set_aabool(const char *val, const struct kernel_param *kp);
1249static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1250#define param_check_aabool param_check_bool
1251static const struct kernel_param_ops param_ops_aabool = {
1252	.flags = KERNEL_PARAM_OPS_FL_NOARG,
1253	.set = param_set_aabool,
1254	.get = param_get_aabool
1255};
1256
1257static int param_set_aauint(const char *val, const struct kernel_param *kp);
1258static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1259#define param_check_aauint param_check_uint
1260static const struct kernel_param_ops param_ops_aauint = {
1261	.set = param_set_aauint,
1262	.get = param_get_aauint
1263};
1264
 
 
 
 
 
 
 
 
 
 
1265static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1266static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1267#define param_check_aalockpolicy param_check_bool
1268static const struct kernel_param_ops param_ops_aalockpolicy = {
1269	.flags = KERNEL_PARAM_OPS_FL_NOARG,
1270	.set = param_set_aalockpolicy,
1271	.get = param_get_aalockpolicy
1272};
1273
1274static int param_set_audit(const char *val, const struct kernel_param *kp);
1275static int param_get_audit(char *buffer, const struct kernel_param *kp);
1276
1277static int param_set_mode(const char *val, const struct kernel_param *kp);
1278static int param_get_mode(char *buffer, const struct kernel_param *kp);
1279
1280/* Flag values, also controllable via /sys/module/apparmor/parameters
1281 * We define special types as we want to do additional mediation.
1282 */
1283
1284/* AppArmor global enforcement switch - complain, enforce, kill */
1285enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1286module_param_call(mode, param_set_mode, param_get_mode,
1287		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1288
1289/* whether policy verification hashing is enabled */
1290bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1291#ifdef CONFIG_SECURITY_APPARMOR_HASH
1292module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1293#endif
1294
 
 
 
 
 
1295/* Debug mode */
1296bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1297module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1298
1299/* Audit mode */
1300enum audit_mode aa_g_audit;
1301module_param_call(audit, param_set_audit, param_get_audit,
1302		  &aa_g_audit, S_IRUSR | S_IWUSR);
1303
1304/* Determines if audit header is included in audited messages.  This
1305 * provides more context if the audit daemon is not running
1306 */
1307bool aa_g_audit_header = true;
1308module_param_named(audit_header, aa_g_audit_header, aabool,
1309		   S_IRUSR | S_IWUSR);
1310
1311/* lock out loading/removal of policy
1312 * TODO: add in at boot loading of policy, which is the only way to
1313 *       load policy, if lock_policy is set
1314 */
1315bool aa_g_lock_policy;
1316module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1317		   S_IRUSR | S_IWUSR);
1318
1319/* Syscall logging mode */
1320bool aa_g_logsyscall;
1321module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1322
1323/* Maximum pathname length before accesses will start getting rejected */
1324unsigned int aa_g_path_max = 2 * PATH_MAX;
1325module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1326
1327/* Determines how paranoid loading of policy is and how much verification
1328 * on the loaded policy is done.
1329 * DEPRECATED: read only as strict checking of load is always done now
1330 * that none root users (user namespaces) can load policy.
1331 */
1332bool aa_g_paranoid_load = true;
1333module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1334
1335static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1336static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1337#define param_check_aaintbool param_check_int
1338static const struct kernel_param_ops param_ops_aaintbool = {
1339	.set = param_set_aaintbool,
1340	.get = param_get_aaintbool
1341};
1342/* Boot time disable flag */
1343static int apparmor_enabled __lsm_ro_after_init = 1;
1344module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1345
1346static int __init apparmor_enabled_setup(char *str)
1347{
1348	unsigned long enabled;
1349	int error = kstrtoul(str, 0, &enabled);
1350	if (!error)
1351		apparmor_enabled = enabled ? 1 : 0;
1352	return 1;
1353}
1354
1355__setup("apparmor=", apparmor_enabled_setup);
1356
1357/* set global flag turning off the ability to load policy */
1358static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1359{
1360	if (!apparmor_enabled)
1361		return -EINVAL;
1362	if (apparmor_initialized && !policy_admin_capable(NULL))
1363		return -EPERM;
1364	return param_set_bool(val, kp);
1365}
1366
1367static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1368{
1369	if (!apparmor_enabled)
1370		return -EINVAL;
1371	if (apparmor_initialized && !policy_view_capable(NULL))
1372		return -EPERM;
1373	return param_get_bool(buffer, kp);
1374}
1375
1376static int param_set_aabool(const char *val, const struct kernel_param *kp)
1377{
1378	if (!apparmor_enabled)
1379		return -EINVAL;
1380	if (apparmor_initialized && !policy_admin_capable(NULL))
1381		return -EPERM;
1382	return param_set_bool(val, kp);
1383}
1384
1385static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1386{
1387	if (!apparmor_enabled)
1388		return -EINVAL;
1389	if (apparmor_initialized && !policy_view_capable(NULL))
1390		return -EPERM;
1391	return param_get_bool(buffer, kp);
1392}
1393
1394static int param_set_aauint(const char *val, const struct kernel_param *kp)
1395{
1396	int error;
1397
1398	if (!apparmor_enabled)
1399		return -EINVAL;
1400	/* file is ro but enforce 2nd line check */
1401	if (apparmor_initialized)
1402		return -EPERM;
1403
1404	error = param_set_uint(val, kp);
 
1405	pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1406
1407	return error;
1408}
1409
1410static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1411{
1412	if (!apparmor_enabled)
1413		return -EINVAL;
1414	if (apparmor_initialized && !policy_view_capable(NULL))
1415		return -EPERM;
1416	return param_get_uint(buffer, kp);
1417}
1418
1419/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1420static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1421{
1422	struct kernel_param kp_local;
1423	bool value;
1424	int error;
1425
1426	if (apparmor_initialized)
1427		return -EPERM;
1428
1429	/* Create local copy, with arg pointing to bool type. */
1430	value = !!*((int *)kp->arg);
1431	memcpy(&kp_local, kp, sizeof(kp_local));
1432	kp_local.arg = &value;
1433
1434	error = param_set_bool(val, &kp_local);
1435	if (!error)
1436		*((int *)kp->arg) = *((bool *)kp_local.arg);
1437	return error;
1438}
1439
1440/*
1441 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1442 * 1/0, this converts the "int that is actually bool" back to bool for
1443 * display in the /sys filesystem, while keeping it "int" for the LSM
1444 * infrastructure.
1445 */
1446static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1447{
1448	struct kernel_param kp_local;
1449	bool value;
1450
1451	/* Create local copy, with arg pointing to bool type. */
1452	value = !!*((int *)kp->arg);
1453	memcpy(&kp_local, kp, sizeof(kp_local));
1454	kp_local.arg = &value;
1455
1456	return param_get_bool(buffer, &kp_local);
1457}
1458
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1459static int param_get_audit(char *buffer, const struct kernel_param *kp)
1460{
1461	if (!apparmor_enabled)
1462		return -EINVAL;
1463	if (apparmor_initialized && !policy_view_capable(NULL))
1464		return -EPERM;
1465	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1466}
1467
1468static int param_set_audit(const char *val, const struct kernel_param *kp)
1469{
1470	int i;
1471
1472	if (!apparmor_enabled)
1473		return -EINVAL;
1474	if (!val)
1475		return -EINVAL;
1476	if (apparmor_initialized && !policy_admin_capable(NULL))
1477		return -EPERM;
1478
1479	i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1480	if (i < 0)
1481		return -EINVAL;
1482
1483	aa_g_audit = i;
1484	return 0;
1485}
1486
1487static int param_get_mode(char *buffer, const struct kernel_param *kp)
1488{
1489	if (!apparmor_enabled)
1490		return -EINVAL;
1491	if (apparmor_initialized && !policy_view_capable(NULL))
1492		return -EPERM;
1493
1494	return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1495}
1496
1497static int param_set_mode(const char *val, const struct kernel_param *kp)
1498{
1499	int i;
1500
1501	if (!apparmor_enabled)
1502		return -EINVAL;
1503	if (!val)
1504		return -EINVAL;
1505	if (apparmor_initialized && !policy_admin_capable(NULL))
1506		return -EPERM;
1507
1508	i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1509			 val);
1510	if (i < 0)
1511		return -EINVAL;
1512
1513	aa_g_profile_mode = i;
1514	return 0;
1515}
1516
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1517/*
1518 * AppArmor init functions
1519 */
1520
1521/**
1522 * set_init_ctx - set a task context and profile on the first task.
1523 *
1524 * TODO: allow setting an alternate profile than unconfined
1525 */
1526static int __init set_init_ctx(void)
1527{
1528	struct cred *cred = (struct cred *)current->real_cred;
1529
1530	set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1531
1532	return 0;
1533}
1534
1535static void destroy_buffers(void)
1536{
1537	u32 i, j;
1538
1539	for_each_possible_cpu(i) {
1540		for_each_cpu_buffer(j) {
1541			kfree(per_cpu(aa_buffers, i).buf[j]);
1542			per_cpu(aa_buffers, i).buf[j] = NULL;
1543		}
 
 
 
1544	}
 
1545}
1546
1547static int __init alloc_buffers(void)
1548{
1549	u32 i, j;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1550
1551	for_each_possible_cpu(i) {
1552		for_each_cpu_buffer(j) {
1553			char *buffer;
1554
1555			if (cpu_to_node(i) > num_online_nodes())
1556				/* fallback to kmalloc for offline nodes */
1557				buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
1558			else
1559				buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
1560						      cpu_to_node(i));
1561			if (!buffer) {
1562				destroy_buffers();
1563				return -ENOMEM;
1564			}
1565			per_cpu(aa_buffers, i).buf[j] = buffer;
1566		}
 
1567	}
1568
1569	return 0;
1570}
1571
1572#ifdef CONFIG_SYSCTL
1573static int apparmor_dointvec(struct ctl_table *table, int write,
1574			     void __user *buffer, size_t *lenp, loff_t *ppos)
1575{
1576	if (!policy_admin_capable(NULL))
1577		return -EPERM;
1578	if (!apparmor_enabled)
1579		return -EINVAL;
1580
1581	return proc_dointvec(table, write, buffer, lenp, ppos);
1582}
1583
1584static struct ctl_path apparmor_sysctl_path[] = {
1585	{ .procname = "kernel", },
1586	{ }
1587};
1588
1589static struct ctl_table apparmor_sysctl_table[] = {
1590	{
1591		.procname       = "unprivileged_userns_apparmor_policy",
1592		.data           = &unprivileged_userns_apparmor_policy,
1593		.maxlen         = sizeof(int),
1594		.mode           = 0600,
1595		.proc_handler   = apparmor_dointvec,
1596	},
1597	{ }
1598};
1599
1600static int __init apparmor_init_sysctl(void)
1601{
1602	return register_sysctl_paths(apparmor_sysctl_path,
1603				     apparmor_sysctl_table) ? 0 : -ENOMEM;
1604}
1605#else
1606static inline int apparmor_init_sysctl(void)
1607{
1608	return 0;
1609}
1610#endif /* CONFIG_SYSCTL */
1611
1612#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
1613static unsigned int apparmor_ip_postroute(void *priv,
1614					  struct sk_buff *skb,
1615					  const struct nf_hook_state *state)
1616{
1617	struct aa_sk_ctx *ctx;
1618	struct sock *sk;
1619
1620	if (!skb->secmark)
1621		return NF_ACCEPT;
1622
1623	sk = skb_to_full_sk(skb);
1624	if (sk == NULL)
1625		return NF_ACCEPT;
1626
1627	ctx = SK_CTX(sk);
1628	if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
1629				    skb->secmark, sk))
1630		return NF_ACCEPT;
1631
1632	return NF_DROP_ERR(-ECONNREFUSED);
1633
1634}
1635
1636static unsigned int apparmor_ipv4_postroute(void *priv,
1637					    struct sk_buff *skb,
1638					    const struct nf_hook_state *state)
1639{
1640	return apparmor_ip_postroute(priv, skb, state);
1641}
1642
1643#if IS_ENABLED(CONFIG_IPV6)
1644static unsigned int apparmor_ipv6_postroute(void *priv,
1645					    struct sk_buff *skb,
1646					    const struct nf_hook_state *state)
1647{
1648	return apparmor_ip_postroute(priv, skb, state);
1649}
1650#endif
1651
1652static const struct nf_hook_ops apparmor_nf_ops[] = {
1653	{
1654		.hook =         apparmor_ipv4_postroute,
1655		.pf =           NFPROTO_IPV4,
1656		.hooknum =      NF_INET_POST_ROUTING,
1657		.priority =     NF_IP_PRI_SELINUX_FIRST,
1658	},
1659#if IS_ENABLED(CONFIG_IPV6)
1660	{
1661		.hook =         apparmor_ipv6_postroute,
1662		.pf =           NFPROTO_IPV6,
1663		.hooknum =      NF_INET_POST_ROUTING,
1664		.priority =     NF_IP6_PRI_SELINUX_FIRST,
1665	},
1666#endif
1667};
1668
1669static int __net_init apparmor_nf_register(struct net *net)
1670{
1671	int ret;
1672
1673	ret = nf_register_net_hooks(net, apparmor_nf_ops,
1674				    ARRAY_SIZE(apparmor_nf_ops));
1675	return ret;
1676}
1677
1678static void __net_exit apparmor_nf_unregister(struct net *net)
1679{
1680	nf_unregister_net_hooks(net, apparmor_nf_ops,
1681				ARRAY_SIZE(apparmor_nf_ops));
1682}
1683
1684static struct pernet_operations apparmor_net_ops = {
1685	.init = apparmor_nf_register,
1686	.exit = apparmor_nf_unregister,
1687};
1688
1689static int __init apparmor_nf_ip_init(void)
1690{
1691	int err;
1692
1693	if (!apparmor_enabled)
1694		return 0;
1695
1696	err = register_pernet_subsys(&apparmor_net_ops);
1697	if (err)
1698		panic("Apparmor: register_pernet_subsys: error %d\n", err);
1699
1700	return 0;
1701}
1702__initcall(apparmor_nf_ip_init);
1703#endif
1704
1705static int __init apparmor_init(void)
1706{
1707	int error;
1708
1709	aa_secids_init();
1710
1711	error = aa_setup_dfa_engine();
1712	if (error) {
1713		AA_ERROR("Unable to setup dfa engine\n");
1714		goto alloc_out;
1715	}
1716
1717	error = aa_alloc_root_ns();
1718	if (error) {
1719		AA_ERROR("Unable to allocate default profile namespace\n");
1720		goto alloc_out;
1721	}
1722
1723	error = apparmor_init_sysctl();
1724	if (error) {
1725		AA_ERROR("Unable to register sysctls\n");
1726		goto alloc_out;
1727
1728	}
1729
1730	error = alloc_buffers();
1731	if (error) {
1732		AA_ERROR("Unable to allocate work buffers\n");
1733		goto buffers_out;
1734	}
1735
1736	error = set_init_ctx();
1737	if (error) {
1738		AA_ERROR("Failed to set context on init task\n");
1739		aa_free_root_ns();
1740		goto buffers_out;
1741	}
1742	security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1743				"apparmor");
1744
1745	/* Report that AppArmor successfully initialized */
1746	apparmor_initialized = 1;
1747	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1748		aa_info_message("AppArmor initialized: complain mode enabled");
1749	else if (aa_g_profile_mode == APPARMOR_KILL)
1750		aa_info_message("AppArmor initialized: kill mode enabled");
1751	else
1752		aa_info_message("AppArmor initialized");
1753
1754	return error;
1755
1756buffers_out:
1757	destroy_buffers();
1758
1759alloc_out:
1760	aa_destroy_aafs();
1761	aa_teardown_dfa_engine();
1762
1763	apparmor_enabled = false;
1764	return error;
1765}
1766
1767DEFINE_LSM(apparmor) = {
1768	.name = "apparmor",
1769	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
1770	.enabled = &apparmor_enabled,
1771	.blobs = &apparmor_blob_sizes,
1772	.init = apparmor_init,
1773};
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * AppArmor security module
   4 *
   5 * This file contains AppArmor LSM hooks.
   6 *
   7 * Copyright (C) 1998-2008 Novell/SUSE
   8 * Copyright 2009-2010 Canonical Ltd.
   9 */
  10
  11#include <linux/lsm_hooks.h>
  12#include <linux/moduleparam.h>
  13#include <linux/mm.h>
  14#include <linux/mman.h>
  15#include <linux/mount.h>
  16#include <linux/namei.h>
  17#include <linux/ptrace.h>
  18#include <linux/ctype.h>
  19#include <linux/sysctl.h>
  20#include <linux/audit.h>
  21#include <linux/user_namespace.h>
  22#include <linux/netfilter_ipv4.h>
  23#include <linux/netfilter_ipv6.h>
  24#include <linux/zlib.h>
  25#include <net/sock.h>
  26#include <uapi/linux/mount.h>
  27
  28#include "include/apparmor.h"
  29#include "include/apparmorfs.h"
  30#include "include/audit.h"
  31#include "include/capability.h"
  32#include "include/cred.h"
  33#include "include/file.h"
  34#include "include/ipc.h"
  35#include "include/net.h"
  36#include "include/path.h"
  37#include "include/label.h"
  38#include "include/policy.h"
  39#include "include/policy_ns.h"
  40#include "include/procattr.h"
  41#include "include/mount.h"
  42#include "include/secid.h"
  43
  44/* Flag indicating whether initialization completed */
  45int apparmor_initialized;
  46
  47union aa_buffer {
  48	struct list_head list;
  49	char buffer[1];
  50};
  51
  52#define RESERVE_COUNT 2
  53static int reserve_count = RESERVE_COUNT;
  54static int buffer_count;
  55
  56static LIST_HEAD(aa_global_buffers);
  57static DEFINE_SPINLOCK(aa_buffers_lock);
  58
  59/*
  60 * LSM hook functions
  61 */
  62
  63/*
  64 * put the associated labels
  65 */
  66static void apparmor_cred_free(struct cred *cred)
  67{
  68	aa_put_label(cred_label(cred));
  69	set_cred_label(cred, NULL);
  70}
  71
  72/*
  73 * allocate the apparmor part of blank credentials
  74 */
  75static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
  76{
  77	set_cred_label(cred, NULL);
  78	return 0;
  79}
  80
  81/*
  82 * prepare new cred label for modification by prepare_cred block
  83 */
  84static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
  85				 gfp_t gfp)
  86{
  87	set_cred_label(new, aa_get_newest_label(cred_label(old)));
  88	return 0;
  89}
  90
  91/*
  92 * transfer the apparmor data to a blank set of creds
  93 */
  94static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
  95{
  96	set_cred_label(new, aa_get_newest_label(cred_label(old)));
  97}
  98
  99static void apparmor_task_free(struct task_struct *task)
 100{
 101
 102	aa_free_task_ctx(task_ctx(task));
 103}
 104
 105static int apparmor_task_alloc(struct task_struct *task,
 106			       unsigned long clone_flags)
 107{
 108	struct aa_task_ctx *new = task_ctx(task);
 109
 110	aa_dup_task_ctx(new, task_ctx(current));
 111
 112	return 0;
 113}
 114
 115static int apparmor_ptrace_access_check(struct task_struct *child,
 116					unsigned int mode)
 117{
 118	struct aa_label *tracer, *tracee;
 119	int error;
 120
 121	tracer = __begin_current_label_crit_section();
 122	tracee = aa_get_task_label(child);
 123	error = aa_may_ptrace(tracer, tracee,
 124			(mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
 125						  : AA_PTRACE_TRACE);
 126	aa_put_label(tracee);
 127	__end_current_label_crit_section(tracer);
 128
 129	return error;
 130}
 131
 132static int apparmor_ptrace_traceme(struct task_struct *parent)
 133{
 134	struct aa_label *tracer, *tracee;
 135	int error;
 136
 137	tracee = __begin_current_label_crit_section();
 138	tracer = aa_get_task_label(parent);
 139	error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
 140	aa_put_label(tracer);
 141	__end_current_label_crit_section(tracee);
 142
 143	return error;
 144}
 145
 146/* Derived from security/commoncap.c:cap_capget */
 147static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
 148			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
 149{
 150	struct aa_label *label;
 151	const struct cred *cred;
 152
 153	rcu_read_lock();
 154	cred = __task_cred(target);
 155	label = aa_get_newest_cred_label(cred);
 156
 157	/*
 158	 * cap_capget is stacked ahead of this and will
 159	 * initialize effective and permitted.
 160	 */
 161	if (!unconfined(label)) {
 162		struct aa_profile *profile;
 163		struct label_it i;
 164
 165		label_for_each_confined(i, label, profile) {
 166			if (COMPLAIN_MODE(profile))
 167				continue;
 168			*effective = cap_intersect(*effective,
 169						   profile->caps.allow);
 170			*permitted = cap_intersect(*permitted,
 171						   profile->caps.allow);
 172		}
 173	}
 174	rcu_read_unlock();
 175	aa_put_label(label);
 176
 177	return 0;
 178}
 179
 180static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
 181			    int cap, unsigned int opts)
 182{
 183	struct aa_label *label;
 184	int error = 0;
 185
 186	label = aa_get_newest_cred_label(cred);
 187	if (!unconfined(label))
 188		error = aa_capable(label, cap, opts);
 189	aa_put_label(label);
 190
 191	return error;
 192}
 193
 194/**
 195 * common_perm - basic common permission check wrapper fn for paths
 196 * @op: operation being checked
 197 * @path: path to check permission of  (NOT NULL)
 198 * @mask: requested permissions mask
 199 * @cond: conditional info for the permission request  (NOT NULL)
 200 *
 201 * Returns: %0 else error code if error or permission denied
 202 */
 203static int common_perm(const char *op, const struct path *path, u32 mask,
 204		       struct path_cond *cond)
 205{
 206	struct aa_label *label;
 207	int error = 0;
 208
 209	label = __begin_current_label_crit_section();
 210	if (!unconfined(label))
 211		error = aa_path_perm(op, label, path, 0, mask, cond);
 212	__end_current_label_crit_section(label);
 213
 214	return error;
 215}
 216
 217/**
 218 * common_perm_cond - common permission wrapper around inode cond
 219 * @op: operation being checked
 220 * @path: location to check (NOT NULL)
 221 * @mask: requested permissions mask
 222 *
 223 * Returns: %0 else error code if error or permission denied
 224 */
 225static int common_perm_cond(const char *op, const struct path *path, u32 mask)
 226{
 227	struct user_namespace *mnt_userns = mnt_user_ns(path->mnt);
 228	struct path_cond cond = {
 229		i_uid_into_mnt(mnt_userns, d_backing_inode(path->dentry)),
 230		d_backing_inode(path->dentry)->i_mode
 231	};
 232
 233	if (!path_mediated_fs(path->dentry))
 234		return 0;
 235
 236	return common_perm(op, path, mask, &cond);
 237}
 238
 239/**
 240 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
 241 * @op: operation being checked
 242 * @dir: directory of the dentry  (NOT NULL)
 243 * @dentry: dentry to check  (NOT NULL)
 244 * @mask: requested permissions mask
 245 * @cond: conditional info for the permission request  (NOT NULL)
 246 *
 247 * Returns: %0 else error code if error or permission denied
 248 */
 249static int common_perm_dir_dentry(const char *op, const struct path *dir,
 250				  struct dentry *dentry, u32 mask,
 251				  struct path_cond *cond)
 252{
 253	struct path path = { .mnt = dir->mnt, .dentry = dentry };
 254
 255	return common_perm(op, &path, mask, cond);
 256}
 257
 258/**
 259 * common_perm_rm - common permission wrapper for operations doing rm
 260 * @op: operation being checked
 261 * @dir: directory that the dentry is in  (NOT NULL)
 262 * @dentry: dentry being rm'd  (NOT NULL)
 263 * @mask: requested permission mask
 264 *
 265 * Returns: %0 else error code if error or permission denied
 266 */
 267static int common_perm_rm(const char *op, const struct path *dir,
 268			  struct dentry *dentry, u32 mask)
 269{
 270	struct inode *inode = d_backing_inode(dentry);
 271	struct user_namespace *mnt_userns = mnt_user_ns(dir->mnt);
 272	struct path_cond cond = { };
 273
 274	if (!inode || !path_mediated_fs(dentry))
 275		return 0;
 276
 277	cond.uid = i_uid_into_mnt(mnt_userns, inode);
 278	cond.mode = inode->i_mode;
 279
 280	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
 281}
 282
 283/**
 284 * common_perm_create - common permission wrapper for operations doing create
 285 * @op: operation being checked
 286 * @dir: directory that dentry will be created in  (NOT NULL)
 287 * @dentry: dentry to create   (NOT NULL)
 288 * @mask: request permission mask
 289 * @mode: created file mode
 290 *
 291 * Returns: %0 else error code if error or permission denied
 292 */
 293static int common_perm_create(const char *op, const struct path *dir,
 294			      struct dentry *dentry, u32 mask, umode_t mode)
 295{
 296	struct path_cond cond = { current_fsuid(), mode };
 297
 298	if (!path_mediated_fs(dir->dentry))
 299		return 0;
 300
 301	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
 302}
 303
 304static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
 305{
 306	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
 307}
 308
 309static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
 310			       umode_t mode)
 311{
 312	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
 313				  S_IFDIR);
 314}
 315
 316static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
 317{
 318	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
 319}
 320
 321static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
 322			       umode_t mode, unsigned int dev)
 323{
 324	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
 325}
 326
 327static int apparmor_path_truncate(const struct path *path)
 328{
 329	return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
 330}
 331
 332static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
 333				 const char *old_name)
 334{
 335	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
 336				  S_IFLNK);
 337}
 338
 339static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
 340			      struct dentry *new_dentry)
 341{
 342	struct aa_label *label;
 343	int error = 0;
 344
 345	if (!path_mediated_fs(old_dentry))
 346		return 0;
 347
 348	label = begin_current_label_crit_section();
 349	if (!unconfined(label))
 350		error = aa_path_link(label, old_dentry, new_dir, new_dentry);
 351	end_current_label_crit_section(label);
 352
 353	return error;
 354}
 355
 356static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
 357				const struct path *new_dir, struct dentry *new_dentry)
 358{
 359	struct aa_label *label;
 360	int error = 0;
 361
 362	if (!path_mediated_fs(old_dentry))
 363		return 0;
 364
 365	label = begin_current_label_crit_section();
 366	if (!unconfined(label)) {
 367		struct user_namespace *mnt_userns = mnt_user_ns(old_dir->mnt);
 368		struct path old_path = { .mnt = old_dir->mnt,
 369					 .dentry = old_dentry };
 370		struct path new_path = { .mnt = new_dir->mnt,
 371					 .dentry = new_dentry };
 372		struct path_cond cond = {
 373			i_uid_into_mnt(mnt_userns, d_backing_inode(old_dentry)),
 374			d_backing_inode(old_dentry)->i_mode
 375		};
 376
 377		error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
 378				     MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
 379				     AA_MAY_SETATTR | AA_MAY_DELETE,
 380				     &cond);
 381		if (!error)
 382			error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
 383					     0, MAY_WRITE | AA_MAY_SETATTR |
 384					     AA_MAY_CREATE, &cond);
 385
 386	}
 387	end_current_label_crit_section(label);
 388
 389	return error;
 390}
 391
 392static int apparmor_path_chmod(const struct path *path, umode_t mode)
 393{
 394	return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
 395}
 396
 397static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
 398{
 399	return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
 400}
 401
 402static int apparmor_inode_getattr(const struct path *path)
 403{
 404	return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
 405}
 406
 407static int apparmor_file_open(struct file *file)
 408{
 409	struct aa_file_ctx *fctx = file_ctx(file);
 410	struct aa_label *label;
 411	int error = 0;
 412
 413	if (!path_mediated_fs(file->f_path.dentry))
 414		return 0;
 415
 416	/* If in exec, permission is handled by bprm hooks.
 417	 * Cache permissions granted by the previous exec check, with
 418	 * implicit read and executable mmap which are required to
 419	 * actually execute the image.
 420	 */
 421	if (current->in_execve) {
 422		fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
 423		return 0;
 424	}
 425
 426	label = aa_get_newest_cred_label(file->f_cred);
 427	if (!unconfined(label)) {
 428		struct user_namespace *mnt_userns = file_mnt_user_ns(file);
 429		struct inode *inode = file_inode(file);
 430		struct path_cond cond = {
 431			i_uid_into_mnt(mnt_userns, inode),
 432			inode->i_mode
 433		};
 434
 435		error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
 436				     aa_map_file_to_perms(file), &cond);
 437		/* todo cache full allowed permissions set and state */
 438		fctx->allow = aa_map_file_to_perms(file);
 439	}
 440	aa_put_label(label);
 441
 442	return error;
 443}
 444
 445static int apparmor_file_alloc_security(struct file *file)
 446{
 447	struct aa_file_ctx *ctx = file_ctx(file);
 448	struct aa_label *label = begin_current_label_crit_section();
 449
 450	spin_lock_init(&ctx->lock);
 451	rcu_assign_pointer(ctx->label, aa_get_label(label));
 452	end_current_label_crit_section(label);
 453	return 0;
 454}
 455
 456static void apparmor_file_free_security(struct file *file)
 457{
 458	struct aa_file_ctx *ctx = file_ctx(file);
 459
 460	if (ctx)
 461		aa_put_label(rcu_access_pointer(ctx->label));
 462}
 463
 464static int common_file_perm(const char *op, struct file *file, u32 mask,
 465			    bool in_atomic)
 466{
 467	struct aa_label *label;
 468	int error = 0;
 469
 470	/* don't reaudit files closed during inheritance */
 471	if (file->f_path.dentry == aa_null.dentry)
 472		return -EACCES;
 473
 474	label = __begin_current_label_crit_section();
 475	error = aa_file_perm(op, label, file, mask, in_atomic);
 476	__end_current_label_crit_section(label);
 477
 478	return error;
 479}
 480
 481static int apparmor_file_receive(struct file *file)
 482{
 483	return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
 484				false);
 485}
 486
 487static int apparmor_file_permission(struct file *file, int mask)
 488{
 489	return common_file_perm(OP_FPERM, file, mask, false);
 490}
 491
 492static int apparmor_file_lock(struct file *file, unsigned int cmd)
 493{
 494	u32 mask = AA_MAY_LOCK;
 495
 496	if (cmd == F_WRLCK)
 497		mask |= MAY_WRITE;
 498
 499	return common_file_perm(OP_FLOCK, file, mask, false);
 500}
 501
 502static int common_mmap(const char *op, struct file *file, unsigned long prot,
 503		       unsigned long flags, bool in_atomic)
 504{
 505	int mask = 0;
 506
 507	if (!file || !file_ctx(file))
 508		return 0;
 509
 510	if (prot & PROT_READ)
 511		mask |= MAY_READ;
 512	/*
 513	 * Private mappings don't require write perms since they don't
 514	 * write back to the files
 515	 */
 516	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
 517		mask |= MAY_WRITE;
 518	if (prot & PROT_EXEC)
 519		mask |= AA_EXEC_MMAP;
 520
 521	return common_file_perm(op, file, mask, in_atomic);
 522}
 523
 524static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
 525			      unsigned long prot, unsigned long flags)
 526{
 527	return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
 528}
 529
 530static int apparmor_file_mprotect(struct vm_area_struct *vma,
 531				  unsigned long reqprot, unsigned long prot)
 532{
 533	return common_mmap(OP_FMPROT, vma->vm_file, prot,
 534			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
 535			   false);
 536}
 537
 538static int apparmor_sb_mount(const char *dev_name, const struct path *path,
 539			     const char *type, unsigned long flags, void *data)
 540{
 541	struct aa_label *label;
 542	int error = 0;
 543
 544	/* Discard magic */
 545	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
 546		flags &= ~MS_MGC_MSK;
 547
 548	flags &= ~AA_MS_IGNORE_MASK;
 549
 550	label = __begin_current_label_crit_section();
 551	if (!unconfined(label)) {
 552		if (flags & MS_REMOUNT)
 553			error = aa_remount(label, path, flags, data);
 554		else if (flags & MS_BIND)
 555			error = aa_bind_mount(label, path, dev_name, flags);
 556		else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
 557				  MS_UNBINDABLE))
 558			error = aa_mount_change_type(label, path, flags);
 559		else if (flags & MS_MOVE)
 560			error = aa_move_mount(label, path, dev_name);
 561		else
 562			error = aa_new_mount(label, dev_name, path, type,
 563					     flags, data);
 564	}
 565	__end_current_label_crit_section(label);
 566
 567	return error;
 568}
 569
 570static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
 571{
 572	struct aa_label *label;
 573	int error = 0;
 574
 575	label = __begin_current_label_crit_section();
 576	if (!unconfined(label))
 577		error = aa_umount(label, mnt, flags);
 578	__end_current_label_crit_section(label);
 579
 580	return error;
 581}
 582
 583static int apparmor_sb_pivotroot(const struct path *old_path,
 584				 const struct path *new_path)
 585{
 586	struct aa_label *label;
 587	int error = 0;
 588
 589	label = aa_get_current_label();
 590	if (!unconfined(label))
 591		error = aa_pivotroot(label, old_path, new_path);
 592	aa_put_label(label);
 593
 594	return error;
 595}
 596
 597static int apparmor_getprocattr(struct task_struct *task, char *name,
 598				char **value)
 599{
 600	int error = -ENOENT;
 601	/* released below */
 602	const struct cred *cred = get_task_cred(task);
 603	struct aa_task_ctx *ctx = task_ctx(current);
 604	struct aa_label *label = NULL;
 605
 606	if (strcmp(name, "current") == 0)
 607		label = aa_get_newest_label(cred_label(cred));
 608	else if (strcmp(name, "prev") == 0  && ctx->previous)
 609		label = aa_get_newest_label(ctx->previous);
 610	else if (strcmp(name, "exec") == 0 && ctx->onexec)
 611		label = aa_get_newest_label(ctx->onexec);
 612	else
 613		error = -EINVAL;
 614
 615	if (label)
 616		error = aa_getprocattr(label, value);
 617
 618	aa_put_label(label);
 619	put_cred(cred);
 620
 621	return error;
 622}
 623
 624static int apparmor_setprocattr(const char *name, void *value,
 625				size_t size)
 626{
 627	char *command, *largs = NULL, *args = value;
 628	size_t arg_size;
 629	int error;
 630	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
 631
 632	if (size == 0)
 633		return -EINVAL;
 634
 635	/* AppArmor requires that the buffer must be null terminated atm */
 636	if (args[size - 1] != '\0') {
 637		/* null terminate */
 638		largs = args = kmalloc(size + 1, GFP_KERNEL);
 639		if (!args)
 640			return -ENOMEM;
 641		memcpy(args, value, size);
 642		args[size] = '\0';
 643	}
 644
 645	error = -EINVAL;
 646	args = strim(args);
 647	command = strsep(&args, " ");
 648	if (!args)
 649		goto out;
 650	args = skip_spaces(args);
 651	if (!*args)
 652		goto out;
 653
 654	arg_size = size - (args - (largs ? largs : (char *) value));
 655	if (strcmp(name, "current") == 0) {
 656		if (strcmp(command, "changehat") == 0) {
 657			error = aa_setprocattr_changehat(args, arg_size,
 658							 AA_CHANGE_NOFLAGS);
 659		} else if (strcmp(command, "permhat") == 0) {
 660			error = aa_setprocattr_changehat(args, arg_size,
 661							 AA_CHANGE_TEST);
 662		} else if (strcmp(command, "changeprofile") == 0) {
 663			error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
 664		} else if (strcmp(command, "permprofile") == 0) {
 665			error = aa_change_profile(args, AA_CHANGE_TEST);
 666		} else if (strcmp(command, "stack") == 0) {
 667			error = aa_change_profile(args, AA_CHANGE_STACK);
 668		} else
 669			goto fail;
 670	} else if (strcmp(name, "exec") == 0) {
 671		if (strcmp(command, "exec") == 0)
 672			error = aa_change_profile(args, AA_CHANGE_ONEXEC);
 673		else if (strcmp(command, "stack") == 0)
 674			error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
 675							 AA_CHANGE_STACK));
 676		else
 677			goto fail;
 678	} else
 679		/* only support the "current" and "exec" process attributes */
 680		goto fail;
 681
 682	if (!error)
 683		error = size;
 684out:
 685	kfree(largs);
 686	return error;
 687
 688fail:
 689	aad(&sa)->label = begin_current_label_crit_section();
 690	aad(&sa)->info = name;
 691	aad(&sa)->error = error = -EINVAL;
 692	aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
 693	end_current_label_crit_section(aad(&sa)->label);
 694	goto out;
 695}
 696
 697/**
 698 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
 699 * @bprm: binprm for the exec  (NOT NULL)
 700 */
 701static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
 702{
 703	struct aa_label *label = aa_current_raw_label();
 704	struct aa_label *new_label = cred_label(bprm->cred);
 705
 706	/* bail out if unconfined or not changing profile */
 707	if ((new_label->proxy == label->proxy) ||
 708	    (unconfined(new_label)))
 709		return;
 710
 711	aa_inherit_files(bprm->cred, current->files);
 712
 713	current->pdeath_signal = 0;
 714
 715	/* reset soft limits and set hard limits for the new label */
 716	__aa_transition_rlimits(label, new_label);
 717}
 718
 719/**
 720 * apparmor_bprm_committed_cred - do cleanup after new creds committed
 721 * @bprm: binprm for the exec  (NOT NULL)
 722 */
 723static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
 724{
 725	/* clear out temporary/transitional state from the context */
 726	aa_clear_task_ctx_trans(task_ctx(current));
 727
 728	return;
 729}
 730
 731static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
 732{
 733	struct aa_label *label = aa_get_task_label(p);
 734	*secid = label->secid;
 735	aa_put_label(label);
 736}
 737
 738static int apparmor_task_setrlimit(struct task_struct *task,
 739		unsigned int resource, struct rlimit *new_rlim)
 740{
 741	struct aa_label *label = __begin_current_label_crit_section();
 742	int error = 0;
 743
 744	if (!unconfined(label))
 745		error = aa_task_setrlimit(label, task, resource, new_rlim);
 746	__end_current_label_crit_section(label);
 747
 748	return error;
 749}
 750
 751static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
 752			      int sig, const struct cred *cred)
 753{
 754	struct aa_label *cl, *tl;
 755	int error;
 756
 757	if (cred) {
 758		/*
 759		 * Dealing with USB IO specific behavior
 760		 */
 761		cl = aa_get_newest_cred_label(cred);
 762		tl = aa_get_task_label(target);
 763		error = aa_may_signal(cl, tl, sig);
 764		aa_put_label(cl);
 765		aa_put_label(tl);
 766		return error;
 767	}
 768
 769	cl = __begin_current_label_crit_section();
 770	tl = aa_get_task_label(target);
 771	error = aa_may_signal(cl, tl, sig);
 772	aa_put_label(tl);
 773	__end_current_label_crit_section(cl);
 774
 775	return error;
 776}
 777
 778/**
 779 * apparmor_sk_alloc_security - allocate and attach the sk_security field
 780 */
 781static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
 782{
 783	struct aa_sk_ctx *ctx;
 784
 785	ctx = kzalloc(sizeof(*ctx), flags);
 786	if (!ctx)
 787		return -ENOMEM;
 788
 789	SK_CTX(sk) = ctx;
 790
 791	return 0;
 792}
 793
 794/**
 795 * apparmor_sk_free_security - free the sk_security field
 796 */
 797static void apparmor_sk_free_security(struct sock *sk)
 798{
 799	struct aa_sk_ctx *ctx = SK_CTX(sk);
 800
 801	SK_CTX(sk) = NULL;
 802	aa_put_label(ctx->label);
 803	aa_put_label(ctx->peer);
 804	kfree(ctx);
 805}
 806
 807/**
 808 * apparmor_clone_security - clone the sk_security field
 809 */
 810static void apparmor_sk_clone_security(const struct sock *sk,
 811				       struct sock *newsk)
 812{
 813	struct aa_sk_ctx *ctx = SK_CTX(sk);
 814	struct aa_sk_ctx *new = SK_CTX(newsk);
 815
 816	if (new->label)
 817		aa_put_label(new->label);
 818	new->label = aa_get_label(ctx->label);
 819
 820	if (new->peer)
 821		aa_put_label(new->peer);
 822	new->peer = aa_get_label(ctx->peer);
 823}
 824
 825/**
 826 * apparmor_socket_create - check perms before creating a new socket
 827 */
 828static int apparmor_socket_create(int family, int type, int protocol, int kern)
 829{
 830	struct aa_label *label;
 831	int error = 0;
 832
 833	AA_BUG(in_interrupt());
 834
 835	label = begin_current_label_crit_section();
 836	if (!(kern || unconfined(label)))
 837		error = af_select(family,
 838				  create_perm(label, family, type, protocol),
 839				  aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
 840					     family, type, protocol));
 841	end_current_label_crit_section(label);
 842
 843	return error;
 844}
 845
 846/**
 847 * apparmor_socket_post_create - setup the per-socket security struct
 848 *
 849 * Note:
 850 * -   kernel sockets currently labeled unconfined but we may want to
 851 *     move to a special kernel label
 852 * -   socket may not have sk here if created with sock_create_lite or
 853 *     sock_alloc. These should be accept cases which will be handled in
 854 *     sock_graft.
 855 */
 856static int apparmor_socket_post_create(struct socket *sock, int family,
 857				       int type, int protocol, int kern)
 858{
 859	struct aa_label *label;
 860
 861	if (kern) {
 862		struct aa_ns *ns = aa_get_current_ns();
 863
 864		label = aa_get_label(ns_unconfined(ns));
 865		aa_put_ns(ns);
 866	} else
 867		label = aa_get_current_label();
 868
 869	if (sock->sk) {
 870		struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
 871
 872		aa_put_label(ctx->label);
 873		ctx->label = aa_get_label(label);
 874	}
 875	aa_put_label(label);
 876
 877	return 0;
 878}
 879
 880/**
 881 * apparmor_socket_bind - check perms before bind addr to socket
 882 */
 883static int apparmor_socket_bind(struct socket *sock,
 884				struct sockaddr *address, int addrlen)
 885{
 886	AA_BUG(!sock);
 887	AA_BUG(!sock->sk);
 888	AA_BUG(!address);
 889	AA_BUG(in_interrupt());
 890
 891	return af_select(sock->sk->sk_family,
 892			 bind_perm(sock, address, addrlen),
 893			 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
 894}
 895
 896/**
 897 * apparmor_socket_connect - check perms before connecting @sock to @address
 898 */
 899static int apparmor_socket_connect(struct socket *sock,
 900				   struct sockaddr *address, int addrlen)
 901{
 902	AA_BUG(!sock);
 903	AA_BUG(!sock->sk);
 904	AA_BUG(!address);
 905	AA_BUG(in_interrupt());
 906
 907	return af_select(sock->sk->sk_family,
 908			 connect_perm(sock, address, addrlen),
 909			 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
 910}
 911
 912/**
 913 * apparmor_socket_list - check perms before allowing listen
 914 */
 915static int apparmor_socket_listen(struct socket *sock, int backlog)
 916{
 917	AA_BUG(!sock);
 918	AA_BUG(!sock->sk);
 919	AA_BUG(in_interrupt());
 920
 921	return af_select(sock->sk->sk_family,
 922			 listen_perm(sock, backlog),
 923			 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
 924}
 925
 926/**
 927 * apparmor_socket_accept - check perms before accepting a new connection.
 928 *
 929 * Note: while @newsock is created and has some information, the accept
 930 *       has not been done.
 931 */
 932static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
 933{
 934	AA_BUG(!sock);
 935	AA_BUG(!sock->sk);
 936	AA_BUG(!newsock);
 937	AA_BUG(in_interrupt());
 938
 939	return af_select(sock->sk->sk_family,
 940			 accept_perm(sock, newsock),
 941			 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
 942}
 943
 944static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
 945			    struct msghdr *msg, int size)
 946{
 947	AA_BUG(!sock);
 948	AA_BUG(!sock->sk);
 949	AA_BUG(!msg);
 950	AA_BUG(in_interrupt());
 951
 952	return af_select(sock->sk->sk_family,
 953			 msg_perm(op, request, sock, msg, size),
 954			 aa_sk_perm(op, request, sock->sk));
 955}
 956
 957/**
 958 * apparmor_socket_sendmsg - check perms before sending msg to another socket
 959 */
 960static int apparmor_socket_sendmsg(struct socket *sock,
 961				   struct msghdr *msg, int size)
 962{
 963	return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
 964}
 965
 966/**
 967 * apparmor_socket_recvmsg - check perms before receiving a message
 968 */
 969static int apparmor_socket_recvmsg(struct socket *sock,
 970				   struct msghdr *msg, int size, int flags)
 971{
 972	return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
 973}
 974
 975/* revaliation, get/set attr, shutdown */
 976static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
 977{
 978	AA_BUG(!sock);
 979	AA_BUG(!sock->sk);
 980	AA_BUG(in_interrupt());
 981
 982	return af_select(sock->sk->sk_family,
 983			 sock_perm(op, request, sock),
 984			 aa_sk_perm(op, request, sock->sk));
 985}
 986
 987/**
 988 * apparmor_socket_getsockname - check perms before getting the local address
 989 */
 990static int apparmor_socket_getsockname(struct socket *sock)
 991{
 992	return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
 993}
 994
 995/**
 996 * apparmor_socket_getpeername - check perms before getting remote address
 997 */
 998static int apparmor_socket_getpeername(struct socket *sock)
 999{
1000	return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
1001}
1002
1003/* revaliation, get/set attr, opt */
1004static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
1005			    int level, int optname)
1006{
1007	AA_BUG(!sock);
1008	AA_BUG(!sock->sk);
1009	AA_BUG(in_interrupt());
1010
1011	return af_select(sock->sk->sk_family,
1012			 opt_perm(op, request, sock, level, optname),
1013			 aa_sk_perm(op, request, sock->sk));
1014}
1015
1016/**
1017 * apparmor_getsockopt - check perms before getting socket options
1018 */
1019static int apparmor_socket_getsockopt(struct socket *sock, int level,
1020				      int optname)
1021{
1022	return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
1023				level, optname);
1024}
1025
1026/**
1027 * apparmor_setsockopt - check perms before setting socket options
1028 */
1029static int apparmor_socket_setsockopt(struct socket *sock, int level,
1030				      int optname)
1031{
1032	return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1033				level, optname);
1034}
1035
1036/**
1037 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1038 */
1039static int apparmor_socket_shutdown(struct socket *sock, int how)
1040{
1041	return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1042}
1043
1044#ifdef CONFIG_NETWORK_SECMARK
1045/**
1046 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1047 *
1048 * Note: can not sleep may be called with locks held
1049 *
1050 * dont want protocol specific in __skb_recv_datagram()
1051 * to deny an incoming connection  socket_sock_rcv_skb()
1052 */
1053static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1054{
1055	struct aa_sk_ctx *ctx = SK_CTX(sk);
1056
1057	if (!skb->secmark)
1058		return 0;
1059
1060	return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1061				      skb->secmark, sk);
1062}
1063#endif
1064
1065
1066static struct aa_label *sk_peer_label(struct sock *sk)
1067{
1068	struct aa_sk_ctx *ctx = SK_CTX(sk);
1069
1070	if (ctx->peer)
1071		return ctx->peer;
1072
1073	return ERR_PTR(-ENOPROTOOPT);
1074}
1075
1076/**
1077 * apparmor_socket_getpeersec_stream - get security context of peer
1078 *
1079 * Note: for tcp only valid if using ipsec or cipso on lan
1080 */
1081static int apparmor_socket_getpeersec_stream(struct socket *sock,
1082					     char __user *optval,
1083					     int __user *optlen,
1084					     unsigned int len)
1085{
1086	char *name;
1087	int slen, error = 0;
1088	struct aa_label *label;
1089	struct aa_label *peer;
1090
1091	label = begin_current_label_crit_section();
1092	peer = sk_peer_label(sock->sk);
1093	if (IS_ERR(peer)) {
1094		error = PTR_ERR(peer);
1095		goto done;
1096	}
1097	slen = aa_label_asxprint(&name, labels_ns(label), peer,
1098				 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1099				 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1100	/* don't include terminating \0 in slen, it breaks some apps */
1101	if (slen < 0) {
1102		error = -ENOMEM;
1103	} else {
1104		if (slen > len) {
1105			error = -ERANGE;
1106		} else if (copy_to_user(optval, name, slen)) {
1107			error = -EFAULT;
1108			goto out;
1109		}
1110		if (put_user(slen, optlen))
1111			error = -EFAULT;
1112out:
1113		kfree(name);
1114
1115	}
1116
1117done:
1118	end_current_label_crit_section(label);
1119
1120	return error;
1121}
1122
1123/**
1124 * apparmor_socket_getpeersec_dgram - get security label of packet
1125 * @sock: the peer socket
1126 * @skb: packet data
1127 * @secid: pointer to where to put the secid of the packet
1128 *
1129 * Sets the netlabel socket state on sk from parent
1130 */
1131static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1132					    struct sk_buff *skb, u32 *secid)
1133
1134{
1135	/* TODO: requires secid support */
1136	return -ENOPROTOOPT;
1137}
1138
1139/**
1140 * apparmor_sock_graft - Initialize newly created socket
1141 * @sk: child sock
1142 * @parent: parent socket
1143 *
1144 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1145 *       just set sk security information off of current creating process label
1146 *       Labeling of sk for accept case - probably should be sock based
1147 *       instead of task, because of the case where an implicitly labeled
1148 *       socket is shared by different tasks.
1149 */
1150static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1151{
1152	struct aa_sk_ctx *ctx = SK_CTX(sk);
1153
1154	if (!ctx->label)
1155		ctx->label = aa_get_current_label();
1156}
1157
1158#ifdef CONFIG_NETWORK_SECMARK
1159static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
1160				      struct request_sock *req)
1161{
1162	struct aa_sk_ctx *ctx = SK_CTX(sk);
1163
1164	if (!skb->secmark)
1165		return 0;
1166
1167	return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1168				      skb->secmark, sk);
1169}
1170#endif
1171
1172/*
1173 * The cred blob is a pointer to, not an instance of, an aa_task_ctx.
1174 */
1175struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
1176	.lbs_cred = sizeof(struct aa_task_ctx *),
1177	.lbs_file = sizeof(struct aa_file_ctx),
1178	.lbs_task = sizeof(struct aa_task_ctx),
1179};
1180
1181static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1182	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1183	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1184	LSM_HOOK_INIT(capget, apparmor_capget),
1185	LSM_HOOK_INIT(capable, apparmor_capable),
1186
1187	LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1188	LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1189	LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1190
1191	LSM_HOOK_INIT(path_link, apparmor_path_link),
1192	LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1193	LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1194	LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1195	LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1196	LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1197	LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1198	LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1199	LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1200	LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1201	LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1202
1203	LSM_HOOK_INIT(file_open, apparmor_file_open),
1204	LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1205	LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1206	LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1207	LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1208	LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1209	LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1210	LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1211
1212	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1213	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1214
1215	LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1216	LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1217	LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1218
1219	LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1220	LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1221	LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1222	LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1223	LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1224	LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1225	LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1226	LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1227	LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1228	LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1229	LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1230	LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1231	LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1232#ifdef CONFIG_NETWORK_SECMARK
1233	LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1234#endif
1235	LSM_HOOK_INIT(socket_getpeersec_stream,
1236		      apparmor_socket_getpeersec_stream),
1237	LSM_HOOK_INIT(socket_getpeersec_dgram,
1238		      apparmor_socket_getpeersec_dgram),
1239	LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1240#ifdef CONFIG_NETWORK_SECMARK
1241	LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1242#endif
1243
1244	LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1245	LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1246	LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1247	LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1248
1249	LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
1250	LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1251	LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1252
1253	LSM_HOOK_INIT(task_free, apparmor_task_free),
1254	LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1255	LSM_HOOK_INIT(task_getsecid_subj, apparmor_task_getsecid),
1256	LSM_HOOK_INIT(task_getsecid_obj, apparmor_task_getsecid),
1257	LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1258	LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1259
1260#ifdef CONFIG_AUDIT
1261	LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1262	LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1263	LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1264	LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1265#endif
1266
1267	LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1268	LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1269	LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1270};
1271
1272/*
1273 * AppArmor sysfs module parameters
1274 */
1275
1276static int param_set_aabool(const char *val, const struct kernel_param *kp);
1277static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1278#define param_check_aabool param_check_bool
1279static const struct kernel_param_ops param_ops_aabool = {
1280	.flags = KERNEL_PARAM_OPS_FL_NOARG,
1281	.set = param_set_aabool,
1282	.get = param_get_aabool
1283};
1284
1285static int param_set_aauint(const char *val, const struct kernel_param *kp);
1286static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1287#define param_check_aauint param_check_uint
1288static const struct kernel_param_ops param_ops_aauint = {
1289	.set = param_set_aauint,
1290	.get = param_get_aauint
1291};
1292
1293static int param_set_aacompressionlevel(const char *val,
1294					const struct kernel_param *kp);
1295static int param_get_aacompressionlevel(char *buffer,
1296					const struct kernel_param *kp);
1297#define param_check_aacompressionlevel param_check_int
1298static const struct kernel_param_ops param_ops_aacompressionlevel = {
1299	.set = param_set_aacompressionlevel,
1300	.get = param_get_aacompressionlevel
1301};
1302
1303static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1304static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1305#define param_check_aalockpolicy param_check_bool
1306static const struct kernel_param_ops param_ops_aalockpolicy = {
1307	.flags = KERNEL_PARAM_OPS_FL_NOARG,
1308	.set = param_set_aalockpolicy,
1309	.get = param_get_aalockpolicy
1310};
1311
1312static int param_set_audit(const char *val, const struct kernel_param *kp);
1313static int param_get_audit(char *buffer, const struct kernel_param *kp);
1314
1315static int param_set_mode(const char *val, const struct kernel_param *kp);
1316static int param_get_mode(char *buffer, const struct kernel_param *kp);
1317
1318/* Flag values, also controllable via /sys/module/apparmor/parameters
1319 * We define special types as we want to do additional mediation.
1320 */
1321
1322/* AppArmor global enforcement switch - complain, enforce, kill */
1323enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1324module_param_call(mode, param_set_mode, param_get_mode,
1325		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1326
1327/* whether policy verification hashing is enabled */
1328bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1329#ifdef CONFIG_SECURITY_APPARMOR_HASH
1330module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1331#endif
1332
1333/* policy loaddata compression level */
1334int aa_g_rawdata_compression_level = Z_DEFAULT_COMPRESSION;
1335module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
1336		   aacompressionlevel, 0400);
1337
1338/* Debug mode */
1339bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1340module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1341
1342/* Audit mode */
1343enum audit_mode aa_g_audit;
1344module_param_call(audit, param_set_audit, param_get_audit,
1345		  &aa_g_audit, S_IRUSR | S_IWUSR);
1346
1347/* Determines if audit header is included in audited messages.  This
1348 * provides more context if the audit daemon is not running
1349 */
1350bool aa_g_audit_header = true;
1351module_param_named(audit_header, aa_g_audit_header, aabool,
1352		   S_IRUSR | S_IWUSR);
1353
1354/* lock out loading/removal of policy
1355 * TODO: add in at boot loading of policy, which is the only way to
1356 *       load policy, if lock_policy is set
1357 */
1358bool aa_g_lock_policy;
1359module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1360		   S_IRUSR | S_IWUSR);
1361
1362/* Syscall logging mode */
1363bool aa_g_logsyscall;
1364module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1365
1366/* Maximum pathname length before accesses will start getting rejected */
1367unsigned int aa_g_path_max = 2 * PATH_MAX;
1368module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1369
1370/* Determines how paranoid loading of policy is and how much verification
1371 * on the loaded policy is done.
1372 * DEPRECATED: read only as strict checking of load is always done now
1373 * that none root users (user namespaces) can load policy.
1374 */
1375bool aa_g_paranoid_load = true;
1376module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1377
1378static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1379static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1380#define param_check_aaintbool param_check_int
1381static const struct kernel_param_ops param_ops_aaintbool = {
1382	.set = param_set_aaintbool,
1383	.get = param_get_aaintbool
1384};
1385/* Boot time disable flag */
1386static int apparmor_enabled __lsm_ro_after_init = 1;
1387module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1388
1389static int __init apparmor_enabled_setup(char *str)
1390{
1391	unsigned long enabled;
1392	int error = kstrtoul(str, 0, &enabled);
1393	if (!error)
1394		apparmor_enabled = enabled ? 1 : 0;
1395	return 1;
1396}
1397
1398__setup("apparmor=", apparmor_enabled_setup);
1399
1400/* set global flag turning off the ability to load policy */
1401static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1402{
1403	if (!apparmor_enabled)
1404		return -EINVAL;
1405	if (apparmor_initialized && !policy_admin_capable(NULL))
1406		return -EPERM;
1407	return param_set_bool(val, kp);
1408}
1409
1410static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1411{
1412	if (!apparmor_enabled)
1413		return -EINVAL;
1414	if (apparmor_initialized && !policy_view_capable(NULL))
1415		return -EPERM;
1416	return param_get_bool(buffer, kp);
1417}
1418
1419static int param_set_aabool(const char *val, const struct kernel_param *kp)
1420{
1421	if (!apparmor_enabled)
1422		return -EINVAL;
1423	if (apparmor_initialized && !policy_admin_capable(NULL))
1424		return -EPERM;
1425	return param_set_bool(val, kp);
1426}
1427
1428static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1429{
1430	if (!apparmor_enabled)
1431		return -EINVAL;
1432	if (apparmor_initialized && !policy_view_capable(NULL))
1433		return -EPERM;
1434	return param_get_bool(buffer, kp);
1435}
1436
1437static int param_set_aauint(const char *val, const struct kernel_param *kp)
1438{
1439	int error;
1440
1441	if (!apparmor_enabled)
1442		return -EINVAL;
1443	/* file is ro but enforce 2nd line check */
1444	if (apparmor_initialized)
1445		return -EPERM;
1446
1447	error = param_set_uint(val, kp);
1448	aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
1449	pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1450
1451	return error;
1452}
1453
1454static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1455{
1456	if (!apparmor_enabled)
1457		return -EINVAL;
1458	if (apparmor_initialized && !policy_view_capable(NULL))
1459		return -EPERM;
1460	return param_get_uint(buffer, kp);
1461}
1462
1463/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1464static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1465{
1466	struct kernel_param kp_local;
1467	bool value;
1468	int error;
1469
1470	if (apparmor_initialized)
1471		return -EPERM;
1472
1473	/* Create local copy, with arg pointing to bool type. */
1474	value = !!*((int *)kp->arg);
1475	memcpy(&kp_local, kp, sizeof(kp_local));
1476	kp_local.arg = &value;
1477
1478	error = param_set_bool(val, &kp_local);
1479	if (!error)
1480		*((int *)kp->arg) = *((bool *)kp_local.arg);
1481	return error;
1482}
1483
1484/*
1485 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1486 * 1/0, this converts the "int that is actually bool" back to bool for
1487 * display in the /sys filesystem, while keeping it "int" for the LSM
1488 * infrastructure.
1489 */
1490static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1491{
1492	struct kernel_param kp_local;
1493	bool value;
1494
1495	/* Create local copy, with arg pointing to bool type. */
1496	value = !!*((int *)kp->arg);
1497	memcpy(&kp_local, kp, sizeof(kp_local));
1498	kp_local.arg = &value;
1499
1500	return param_get_bool(buffer, &kp_local);
1501}
1502
1503static int param_set_aacompressionlevel(const char *val,
1504					const struct kernel_param *kp)
1505{
1506	int error;
1507
1508	if (!apparmor_enabled)
1509		return -EINVAL;
1510	if (apparmor_initialized)
1511		return -EPERM;
1512
1513	error = param_set_int(val, kp);
1514
1515	aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
1516					       Z_NO_COMPRESSION,
1517					       Z_BEST_COMPRESSION);
1518	pr_info("AppArmor: policy rawdata compression level set to %u\n",
1519		aa_g_rawdata_compression_level);
1520
1521	return error;
1522}
1523
1524static int param_get_aacompressionlevel(char *buffer,
1525					const struct kernel_param *kp)
1526{
1527	if (!apparmor_enabled)
1528		return -EINVAL;
1529	if (apparmor_initialized && !policy_view_capable(NULL))
1530		return -EPERM;
1531	return param_get_int(buffer, kp);
1532}
1533
1534static int param_get_audit(char *buffer, const struct kernel_param *kp)
1535{
1536	if (!apparmor_enabled)
1537		return -EINVAL;
1538	if (apparmor_initialized && !policy_view_capable(NULL))
1539		return -EPERM;
1540	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1541}
1542
1543static int param_set_audit(const char *val, const struct kernel_param *kp)
1544{
1545	int i;
1546
1547	if (!apparmor_enabled)
1548		return -EINVAL;
1549	if (!val)
1550		return -EINVAL;
1551	if (apparmor_initialized && !policy_admin_capable(NULL))
1552		return -EPERM;
1553
1554	i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1555	if (i < 0)
1556		return -EINVAL;
1557
1558	aa_g_audit = i;
1559	return 0;
1560}
1561
1562static int param_get_mode(char *buffer, const struct kernel_param *kp)
1563{
1564	if (!apparmor_enabled)
1565		return -EINVAL;
1566	if (apparmor_initialized && !policy_view_capable(NULL))
1567		return -EPERM;
1568
1569	return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1570}
1571
1572static int param_set_mode(const char *val, const struct kernel_param *kp)
1573{
1574	int i;
1575
1576	if (!apparmor_enabled)
1577		return -EINVAL;
1578	if (!val)
1579		return -EINVAL;
1580	if (apparmor_initialized && !policy_admin_capable(NULL))
1581		return -EPERM;
1582
1583	i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1584			 val);
1585	if (i < 0)
1586		return -EINVAL;
1587
1588	aa_g_profile_mode = i;
1589	return 0;
1590}
1591
1592char *aa_get_buffer(bool in_atomic)
1593{
1594	union aa_buffer *aa_buf;
1595	bool try_again = true;
1596	gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1597
1598retry:
1599	spin_lock(&aa_buffers_lock);
1600	if (buffer_count > reserve_count ||
1601	    (in_atomic && !list_empty(&aa_global_buffers))) {
1602		aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1603					  list);
1604		list_del(&aa_buf->list);
1605		buffer_count--;
1606		spin_unlock(&aa_buffers_lock);
1607		return &aa_buf->buffer[0];
1608	}
1609	if (in_atomic) {
1610		/*
1611		 * out of reserve buffers and in atomic context so increase
1612		 * how many buffers to keep in reserve
1613		 */
1614		reserve_count++;
1615		flags = GFP_ATOMIC;
1616	}
1617	spin_unlock(&aa_buffers_lock);
1618
1619	if (!in_atomic)
1620		might_sleep();
1621	aa_buf = kmalloc(aa_g_path_max, flags);
1622	if (!aa_buf) {
1623		if (try_again) {
1624			try_again = false;
1625			goto retry;
1626		}
1627		pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
1628		return NULL;
1629	}
1630	return &aa_buf->buffer[0];
1631}
1632
1633void aa_put_buffer(char *buf)
1634{
1635	union aa_buffer *aa_buf;
1636
1637	if (!buf)
1638		return;
1639	aa_buf = container_of(buf, union aa_buffer, buffer[0]);
1640
1641	spin_lock(&aa_buffers_lock);
1642	list_add(&aa_buf->list, &aa_global_buffers);
1643	buffer_count++;
1644	spin_unlock(&aa_buffers_lock);
1645}
1646
1647/*
1648 * AppArmor init functions
1649 */
1650
1651/**
1652 * set_init_ctx - set a task context and profile on the first task.
1653 *
1654 * TODO: allow setting an alternate profile than unconfined
1655 */
1656static int __init set_init_ctx(void)
1657{
1658	struct cred *cred = (__force struct cred *)current->real_cred;
1659
1660	set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1661
1662	return 0;
1663}
1664
1665static void destroy_buffers(void)
1666{
1667	union aa_buffer *aa_buf;
1668
1669	spin_lock(&aa_buffers_lock);
1670	while (!list_empty(&aa_global_buffers)) {
1671		aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1672					 list);
1673		list_del(&aa_buf->list);
1674		spin_unlock(&aa_buffers_lock);
1675		kfree(aa_buf);
1676		spin_lock(&aa_buffers_lock);
1677	}
1678	spin_unlock(&aa_buffers_lock);
1679}
1680
1681static int __init alloc_buffers(void)
1682{
1683	union aa_buffer *aa_buf;
1684	int i, num;
1685
1686	/*
1687	 * A function may require two buffers at once. Usually the buffers are
1688	 * used for a short period of time and are shared. On UP kernel buffers
1689	 * two should be enough, with more CPUs it is possible that more
1690	 * buffers will be used simultaneously. The preallocated pool may grow.
1691	 * This preallocation has also the side-effect that AppArmor will be
1692	 * disabled early at boot if aa_g_path_max is extremly high.
1693	 */
1694	if (num_online_cpus() > 1)
1695		num = 4 + RESERVE_COUNT;
1696	else
1697		num = 2 + RESERVE_COUNT;
1698
1699	for (i = 0; i < num; i++) {
1700
1701		aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
1702				 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1703		if (!aa_buf) {
1704			destroy_buffers();
1705			return -ENOMEM;
 
 
 
 
 
 
 
 
1706		}
1707		aa_put_buffer(&aa_buf->buffer[0]);
1708	}
 
1709	return 0;
1710}
1711
1712#ifdef CONFIG_SYSCTL
1713static int apparmor_dointvec(struct ctl_table *table, int write,
1714			     void *buffer, size_t *lenp, loff_t *ppos)
1715{
1716	if (!policy_admin_capable(NULL))
1717		return -EPERM;
1718	if (!apparmor_enabled)
1719		return -EINVAL;
1720
1721	return proc_dointvec(table, write, buffer, lenp, ppos);
1722}
1723
1724static struct ctl_path apparmor_sysctl_path[] = {
1725	{ .procname = "kernel", },
1726	{ }
1727};
1728
1729static struct ctl_table apparmor_sysctl_table[] = {
1730	{
1731		.procname       = "unprivileged_userns_apparmor_policy",
1732		.data           = &unprivileged_userns_apparmor_policy,
1733		.maxlen         = sizeof(int),
1734		.mode           = 0600,
1735		.proc_handler   = apparmor_dointvec,
1736	},
1737	{ }
1738};
1739
1740static int __init apparmor_init_sysctl(void)
1741{
1742	return register_sysctl_paths(apparmor_sysctl_path,
1743				     apparmor_sysctl_table) ? 0 : -ENOMEM;
1744}
1745#else
1746static inline int apparmor_init_sysctl(void)
1747{
1748	return 0;
1749}
1750#endif /* CONFIG_SYSCTL */
1751
1752#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
1753static unsigned int apparmor_ip_postroute(void *priv,
1754					  struct sk_buff *skb,
1755					  const struct nf_hook_state *state)
1756{
1757	struct aa_sk_ctx *ctx;
1758	struct sock *sk;
1759
1760	if (!skb->secmark)
1761		return NF_ACCEPT;
1762
1763	sk = skb_to_full_sk(skb);
1764	if (sk == NULL)
1765		return NF_ACCEPT;
1766
1767	ctx = SK_CTX(sk);
1768	if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
1769				    skb->secmark, sk))
1770		return NF_ACCEPT;
1771
1772	return NF_DROP_ERR(-ECONNREFUSED);
1773
1774}
1775
1776static unsigned int apparmor_ipv4_postroute(void *priv,
1777					    struct sk_buff *skb,
1778					    const struct nf_hook_state *state)
1779{
1780	return apparmor_ip_postroute(priv, skb, state);
1781}
1782
1783#if IS_ENABLED(CONFIG_IPV6)
1784static unsigned int apparmor_ipv6_postroute(void *priv,
1785					    struct sk_buff *skb,
1786					    const struct nf_hook_state *state)
1787{
1788	return apparmor_ip_postroute(priv, skb, state);
1789}
1790#endif
1791
1792static const struct nf_hook_ops apparmor_nf_ops[] = {
1793	{
1794		.hook =         apparmor_ipv4_postroute,
1795		.pf =           NFPROTO_IPV4,
1796		.hooknum =      NF_INET_POST_ROUTING,
1797		.priority =     NF_IP_PRI_SELINUX_FIRST,
1798	},
1799#if IS_ENABLED(CONFIG_IPV6)
1800	{
1801		.hook =         apparmor_ipv6_postroute,
1802		.pf =           NFPROTO_IPV6,
1803		.hooknum =      NF_INET_POST_ROUTING,
1804		.priority =     NF_IP6_PRI_SELINUX_FIRST,
1805	},
1806#endif
1807};
1808
1809static int __net_init apparmor_nf_register(struct net *net)
1810{
1811	int ret;
1812
1813	ret = nf_register_net_hooks(net, apparmor_nf_ops,
1814				    ARRAY_SIZE(apparmor_nf_ops));
1815	return ret;
1816}
1817
1818static void __net_exit apparmor_nf_unregister(struct net *net)
1819{
1820	nf_unregister_net_hooks(net, apparmor_nf_ops,
1821				ARRAY_SIZE(apparmor_nf_ops));
1822}
1823
1824static struct pernet_operations apparmor_net_ops = {
1825	.init = apparmor_nf_register,
1826	.exit = apparmor_nf_unregister,
1827};
1828
1829static int __init apparmor_nf_ip_init(void)
1830{
1831	int err;
1832
1833	if (!apparmor_enabled)
1834		return 0;
1835
1836	err = register_pernet_subsys(&apparmor_net_ops);
1837	if (err)
1838		panic("Apparmor: register_pernet_subsys: error %d\n", err);
1839
1840	return 0;
1841}
1842__initcall(apparmor_nf_ip_init);
1843#endif
1844
1845static int __init apparmor_init(void)
1846{
1847	int error;
1848
1849	aa_secids_init();
1850
1851	error = aa_setup_dfa_engine();
1852	if (error) {
1853		AA_ERROR("Unable to setup dfa engine\n");
1854		goto alloc_out;
1855	}
1856
1857	error = aa_alloc_root_ns();
1858	if (error) {
1859		AA_ERROR("Unable to allocate default profile namespace\n");
1860		goto alloc_out;
1861	}
1862
1863	error = apparmor_init_sysctl();
1864	if (error) {
1865		AA_ERROR("Unable to register sysctls\n");
1866		goto alloc_out;
1867
1868	}
1869
1870	error = alloc_buffers();
1871	if (error) {
1872		AA_ERROR("Unable to allocate work buffers\n");
1873		goto alloc_out;
1874	}
1875
1876	error = set_init_ctx();
1877	if (error) {
1878		AA_ERROR("Failed to set context on init task\n");
1879		aa_free_root_ns();
1880		goto buffers_out;
1881	}
1882	security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1883				"apparmor");
1884
1885	/* Report that AppArmor successfully initialized */
1886	apparmor_initialized = 1;
1887	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1888		aa_info_message("AppArmor initialized: complain mode enabled");
1889	else if (aa_g_profile_mode == APPARMOR_KILL)
1890		aa_info_message("AppArmor initialized: kill mode enabled");
1891	else
1892		aa_info_message("AppArmor initialized");
1893
1894	return error;
1895
1896buffers_out:
1897	destroy_buffers();
 
1898alloc_out:
1899	aa_destroy_aafs();
1900	aa_teardown_dfa_engine();
1901
1902	apparmor_enabled = false;
1903	return error;
1904}
1905
1906DEFINE_LSM(apparmor) = {
1907	.name = "apparmor",
1908	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
1909	.enabled = &apparmor_enabled,
1910	.blobs = &apparmor_blob_sizes,
1911	.init = apparmor_init,
1912};