AppArmor: LSM interface, and security module initialization

AppArmor hooks to interface with the LSM, module parameters and module
initialization.
Signed-off-by: NJohn Johansen <john.johansen@canonical.com>
Signed-off-by: NJames Morris <jmorris@namei.org>

security/apparmor/lsm.c

+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor LSM hooks.
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#include <linux/security.h>
+#include <linux/moduleparam.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/ptrace.h>
+#include <linux/ctype.h>
+#include <linux/sysctl.h>
+#include <linux/audit.h>
+#include <net/sock.h>
+
+#include "include/apparmor.h"
+#include "include/apparmorfs.h"
+#include "include/audit.h"
+#include "include/capability.h"
+#include "include/context.h"
+#include "include/file.h"
+#include "include/ipc.h"
+#include "include/path.h"
+#include "include/policy.h"
+#include "include/procattr.h"
+
+/* Flag indicating whether initialization completed */
+int apparmor_initialized __initdata;
+
+/*
+ * LSM hook functions
+ */
+
+/*
+ * free the associated aa_task_cxt and put its profiles
+ */
+static void apparmor_cred_free(struct cred *cred)
+{
+	aa_free_task_context(cred->security);
+	cred->security = NULL;
+}
+
+/*
+ * allocate the apparmor part of blank credentials
+ */
+static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
+{
+	/* freed by apparmor_cred_free */
+	struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
+	if (!cxt)
+		return -ENOMEM;
+
+	cred->security = cxt;
+	return 0;
+}
+
+/*
+ * prepare new aa_task_cxt for modification by prepare_cred block
+ */
+static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
+				 gfp_t gfp)
+{
+	/* freed by apparmor_cred_free */
+	struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
+	if (!cxt)
+		return -ENOMEM;
+
+	aa_dup_task_context(cxt, old->security);
+	new->security = cxt;
+	return 0;
+}
+
+/*
+ * transfer the apparmor data to a blank set of creds
+ */
+static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
+{
+	const struct aa_task_cxt *old_cxt = old->security;
+	struct aa_task_cxt *new_cxt = new->security;
+
+	aa_dup_task_context(new_cxt, old_cxt);
+}
+
+static int apparmor_ptrace_access_check(struct task_struct *child,
+					unsigned int mode)
+{
+	int error = cap_ptrace_access_check(child, mode);
+	if (error)
+		return error;
+
+	return aa_ptrace(current, child, mode);
+}
+
+static int apparmor_ptrace_traceme(struct task_struct *parent)
+{
+	int error = cap_ptrace_traceme(parent);
+	if (error)
+		return error;
+
+	return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
+}
+
+/* Derived from security/commoncap.c:cap_capget */
+static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
+			   kernel_cap_t *inheritable, kernel_cap_t *permitted)
+{
+	struct aa_profile *profile;
+	const struct cred *cred;
+
+	rcu_read_lock();
+	cred = __task_cred(target);
+	profile = aa_cred_profile(cred);
+
+	*effective = cred->cap_effective;
+	*inheritable = cred->cap_inheritable;
+	*permitted = cred->cap_permitted;
+
+	if (!unconfined(profile)) {
+		*effective = cap_intersect(*effective, profile->caps.allow);
+		*permitted = cap_intersect(*permitted, profile->caps.allow);
+	}
+	rcu_read_unlock();
+
+	return 0;
+}
+
+static int apparmor_capable(struct task_struct *task, const struct cred *cred,
+			    int cap, int audit)
+{
+	struct aa_profile *profile;
+	/* cap_capable returns 0 on success, else -EPERM */
+	int error = cap_capable(task, cred, cap, audit);
+	if (!error) {
+		profile = aa_cred_profile(cred);
+		if (!unconfined(profile))
+			error = aa_capable(task, profile, cap, audit);
+	}
+	return error;
+}
+
+/**
+ * common_perm - basic common permission check wrapper fn for paths
+ * @op: operation being checked
+ * @path: path to check permission of  (NOT NULL)
+ * @mask: requested permissions mask
+ * @cond: conditional info for the permission request  (NOT NULL)
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm(int op, struct path *path, u32 mask,
+		       struct path_cond *cond)
+{
+	struct aa_profile *profile;
+	int error = 0;
+
+	profile = __aa_current_profile();
+	if (!unconfined(profile))
+		error = aa_path_perm(op, profile, path, 0, mask, cond);
+
+	return error;
+}
+
+/**
+ * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
+ * @op: operation being checked
+ * @dir: directory of the dentry  (NOT NULL)
+ * @dentry: dentry to check  (NOT NULL)
+ * @mask: requested permissions mask
+ * @cond: conditional info for the permission request  (NOT NULL)
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_dir_dentry(int op, struct path *dir,
+				  struct dentry *dentry, u32 mask,
+				  struct path_cond *cond)
+{
+	struct path path = { dir->mnt, dentry };
+
+	return common_perm(op, &path, mask, cond);
+}
+
+/**
+ * common_perm_mnt_dentry - common permission wrapper when mnt, dentry
+ * @op: operation being checked
+ * @mnt: mount point of dentry (NOT NULL)
+ * @dentry: dentry to check  (NOT NULL)
+ * @mask: requested permissions mask
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_mnt_dentry(int op, struct vfsmount *mnt,
+				  struct dentry *dentry, u32 mask)
+{
+	struct path path = { mnt, dentry };
+	struct path_cond cond = { dentry->d_inode->i_uid,
+				  dentry->d_inode->i_mode
+	};
+
+	return common_perm(op, &path, mask, &cond);
+}
+
+/**
+ * common_perm_rm - common permission wrapper for operations doing rm
+ * @op: operation being checked
+ * @dir: directory that the dentry is in  (NOT NULL)
+ * @dentry: dentry being rm'd  (NOT NULL)
+ * @mask: requested permission mask
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_rm(int op, struct path *dir,
+			  struct dentry *dentry, u32 mask)
+{
+	struct inode *inode = dentry->d_inode;
+	struct path_cond cond = { };
+
+	if (!inode || !dir->mnt || !mediated_filesystem(inode))
+		return 0;
+
+	cond.uid = inode->i_uid;
+	cond.mode = inode->i_mode;
+
+	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
+}
+
+/**
+ * common_perm_create - common permission wrapper for operations doing create
+ * @op: operation being checked
+ * @dir: directory that dentry will be created in  (NOT NULL)
+ * @dentry: dentry to create   (NOT NULL)
+ * @mask: request permission mask
+ * @mode: created file mode
+ *
+ * Returns: %0 else error code if error or permission denied
+ */
+static int common_perm_create(int op, struct path *dir, struct dentry *dentry,
+			      u32 mask, umode_t mode)
+{
+	struct path_cond cond = { current_fsuid(), mode };
+
+	if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode))
+		return 0;
+
+	return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
+}
+
+static int apparmor_path_unlink(struct path *dir, struct dentry *dentry)
+{
+	return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
+}
+
+static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
+			       int mode)
+{
+	return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
+				  S_IFDIR);
+}
+
+static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry)
+{
+	return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
+}
+
+static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
+			       int mode, unsigned int dev)
+{
+	return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
+}
+
+static int apparmor_path_truncate(struct path *path, loff_t length,
+				  unsigned int time_attrs)
+{
+	struct path_cond cond = { path->dentry->d_inode->i_uid,
+				  path->dentry->d_inode->i_mode
+	};
+
+	if (!path->mnt || !mediated_filesystem(path->dentry->d_inode))
+		return 0;
+
+	return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE,
+			   &cond);
+}
+
+static int apparmor_path_symlink(struct path *dir, struct dentry *dentry,
+				 const char *old_name)
+{
+	return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
+				  S_IFLNK);
+}
+
+static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir,
+			      struct dentry *new_dentry)
+{
+	struct aa_profile *profile;
+	int error = 0;
+
+	if (!mediated_filesystem(old_dentry->d_inode))
+		return 0;
+
+	profile = aa_current_profile();
+	if (!unconfined(profile))
+		error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
+	return error;
+}
+
+static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry,
+				struct path *new_dir, struct dentry *new_dentry)
+{
+	struct aa_profile *profile;
+	int error = 0;
+
+	if (!mediated_filesystem(old_dentry->d_inode))
+		return 0;
+
+	profile = aa_current_profile();
+	if (!unconfined(profile)) {
+		struct path old_path = { old_dir->mnt, old_dentry };
+		struct path new_path = { new_dir->mnt, new_dentry };
+		struct path_cond cond = { old_dentry->d_inode->i_uid,
+					  old_dentry->d_inode->i_mode
+		};
+
+		error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
+				     MAY_READ | AA_MAY_META_READ | MAY_WRITE |
+				     AA_MAY_META_WRITE | AA_MAY_DELETE,
+				     &cond);
+		if (!error)
+			error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
+					     0, MAY_WRITE | AA_MAY_META_WRITE |
+					     AA_MAY_CREATE, &cond);
+
+	}
+	return error;
+}
+
+static int apparmor_path_chmod(struct dentry *dentry, struct vfsmount *mnt,
+			       mode_t mode)
+{
+	if (!mediated_filesystem(dentry->d_inode))
+		return 0;
+
+	return common_perm_mnt_dentry(OP_CHMOD, mnt, dentry, AA_MAY_CHMOD);
+}
+
+static int apparmor_path_chown(struct path *path, uid_t uid, gid_t gid)
+{
+	struct path_cond cond =  { path->dentry->d_inode->i_uid,
+				   path->dentry->d_inode->i_mode
+	};
+
+	if (!mediated_filesystem(path->dentry->d_inode))
+		return 0;
+
+	return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond);
+}
+
+static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
+{
+	if (!mediated_filesystem(dentry->d_inode))
+		return 0;
+
+	return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry,
+				      AA_MAY_META_READ);
+}
+
+static int apparmor_dentry_open(struct file *file, const struct cred *cred)
+{
+	struct aa_file_cxt *fcxt = file->f_security;
+	struct aa_profile *profile;
+	int error = 0;
+
+	if (!mediated_filesystem(file->f_path.dentry->d_inode))
+		return 0;
+
+	/* If in exec, permission is handled by bprm hooks.
+	 * Cache permissions granted by the previous exec check, with
+	 * implicit read and executable mmap which are required to
+	 * actually execute the image.
+	 */
+	if (current->in_execve) {
+		fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
+		return 0;
+	}
+
+	profile = aa_cred_profile(cred);
+	if (!unconfined(profile)) {
+		struct inode *inode = file->f_path.dentry->d_inode;
+		struct path_cond cond = { inode->i_uid, inode->i_mode };
+
+		error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
+				     aa_map_file_to_perms(file), &cond);
+		/* todo cache full allowed permissions set and state */
+		fcxt->allow = aa_map_file_to_perms(file);
+	}
+
+	return error;
+}
+
+static int apparmor_file_alloc_security(struct file *file)
+{
+	/* freed by apparmor_file_free_security */
+	file->f_security = aa_alloc_file_context(GFP_KERNEL);
+	if (!file->f_security)
+		return -ENOMEM;
+	return 0;
+
+}
+
+static void apparmor_file_free_security(struct file *file)
+{
+	struct aa_file_cxt *cxt = file->f_security;
+
+	aa_free_file_context(cxt);
+}
+
+static int common_file_perm(int op, struct file *file, u32 mask)
+{
+	struct aa_file_cxt *fcxt = file->f_security;
+	struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
+	int error = 0;
+
+	BUG_ON(!fprofile);
+
+	if (!file->f_path.mnt ||
+	    !mediated_filesystem(file->f_path.dentry->d_inode))
+		return 0;
+
+	profile = __aa_current_profile();
+
+	/* revalidate access, if task is unconfined, or the cached cred
+	 * doesn't match or if the request is for more permissions than
+	 * was granted.
+	 *
+	 * Note: the test for !unconfined(fprofile) is to handle file
+	 *       delegation from unconfined tasks
+	 */
+	if (!unconfined(profile) && !unconfined(fprofile) &&
+	    ((fprofile != profile) || (mask & ~fcxt->allow)))
+		error = aa_file_perm(op, profile, file, mask);
+
+	return error;
+}
+
+static int apparmor_file_permission(struct file *file, int mask)
+{
+	return common_file_perm(OP_FPERM, file, mask);
+}
+
+static int apparmor_file_lock(struct file *file, unsigned int cmd)
+{
+	u32 mask = AA_MAY_LOCK;
+
+	if (cmd == F_WRLCK)
+		mask |= MAY_WRITE;
+
+	return common_file_perm(OP_FLOCK, file, mask);
+}
+
+static int common_mmap(int op, struct file *file, unsigned long prot,
+		       unsigned long flags)
+{
+	struct dentry *dentry;
+	int mask = 0;
+
+	if (!file || !file->f_security)
+		return 0;
+
+	if (prot & PROT_READ)
+		mask |= MAY_READ;
+	/*
+	 * Private mappings don't require write perms since they don't
+	 * write back to the files
+	 */
+	if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
+		mask |= MAY_WRITE;
+	if (prot & PROT_EXEC)
+		mask |= AA_EXEC_MMAP;
+
+	dentry = file->f_path.dentry;
+	return common_file_perm(op, file, mask);
+}
+
+static int apparmor_file_mmap(struct file *file, unsigned long reqprot,
+			      unsigned long prot, unsigned long flags,
+			      unsigned long addr, unsigned long addr_only)
+{
+	int rc = 0;
+
+	/* do DAC check */
+	rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
+	if (rc || addr_only)
+		return rc;
+
+	return common_mmap(OP_FMMAP, file, prot, flags);
+}
+
+static int apparmor_file_mprotect(struct vm_area_struct *vma,
+				  unsigned long reqprot, unsigned long prot)
+{
+	return common_mmap(OP_FMPROT, vma->vm_file, prot,
+			   !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
+}
+
+static int apparmor_getprocattr(struct task_struct *task, char *name,
+				char **value)
+{
+	int error = -ENOENT;
+	struct aa_profile *profile;
+	/* released below */
+	const struct cred *cred = get_task_cred(task);
+	struct aa_task_cxt *cxt = cred->security;
+	profile = aa_cred_profile(cred);
+
+	if (strcmp(name, "current") == 0)
+		error = aa_getprocattr(aa_newest_version(cxt->profile),
+				       value);
+	else if (strcmp(name, "prev") == 0  && cxt->previous)
+		error = aa_getprocattr(aa_newest_version(cxt->previous),
+				       value);
+	else if (strcmp(name, "exec") == 0 && cxt->onexec)
+		error = aa_getprocattr(aa_newest_version(cxt->onexec),
+				       value);
+	else
+		error = -EINVAL;
+
+	put_cred(cred);
+
+	return error;
+}
+
+static int apparmor_setprocattr(struct task_struct *task, char *name,
+				void *value, size_t size)
+{
+	char *command, *args = value;
+	size_t arg_size;
+	int error;
+
+	if (size == 0)
+		return -EINVAL;
+	/* args points to a PAGE_SIZE buffer, AppArmor requires that
+	 * the buffer must be null terminated or have size <= PAGE_SIZE -1
+	 * so that AppArmor can null terminate them
+	 */
+	if (args[size - 1] != '\0') {
+		if (size == PAGE_SIZE)
+			return -EINVAL;
+		args[size] = '\0';
+	}
+
+	/* task can only write its own attributes */
+	if (current != task)
+		return -EACCES;
+
+	args = value;
+	args = strim(args);
+	command = strsep(&args, " ");
+	if (!args)
+		return -EINVAL;
+	args = skip_spaces(args);
+	if (!*args)
+		return -EINVAL;
+
+	arg_size = size - (args - (char *) value);
+	if (strcmp(name, "current") == 0) {
+		if (strcmp(command, "changehat") == 0) {
+			error = aa_setprocattr_changehat(args, arg_size,
+							 !AA_DO_TEST);
+		} else if (strcmp(command, "permhat") == 0) {
+			error = aa_setprocattr_changehat(args, arg_size,
+							 AA_DO_TEST);
+		} else if (strcmp(command, "changeprofile") == 0) {
+			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
+							     !AA_DO_TEST);
+		} else if (strcmp(command, "permprofile") == 0) {
+			error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
+							     AA_DO_TEST);
+		} else if (strcmp(command, "permipc") == 0) {
+			error = aa_setprocattr_permipc(args);
+		} else {
+			struct common_audit_data sa;
+			COMMON_AUDIT_DATA_INIT(&sa, NONE);
+			sa.aad.op = OP_SETPROCATTR;
+			sa.aad.info = name;
+			sa.aad.error = -EINVAL;
+			return aa_audit(AUDIT_APPARMOR_DENIED, NULL, GFP_KERNEL,
+					&sa, NULL);
+		}
+	} else if (strcmp(name, "exec") == 0) {
+		error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
+						     !AA_DO_TEST);
+	} else {
+		/* only support the "current" and "exec" process attributes */
+		return -EINVAL;
+	}
+	if (!error)
+		error = size;
+	return error;
+}
+
+static int apparmor_task_setrlimit(unsigned int resource,
+				   struct rlimit *new_rlim)
+{
+	struct aa_profile *profile = aa_current_profile();
+	int error = 0;
+
+	if (!unconfined(profile))
+		error = aa_task_setrlimit(profile, resource, new_rlim);
+
+	return error;
+}
+
+static struct security_operations apparmor_ops = {
+	.name =				"apparmor",
+
+	.ptrace_access_check =		apparmor_ptrace_access_check,
+	.ptrace_traceme =		apparmor_ptrace_traceme,
+	.capget =			apparmor_capget,
+	.capable =			apparmor_capable,
+
+	.path_link =			apparmor_path_link,
+	.path_unlink =			apparmor_path_unlink,
+	.path_symlink =			apparmor_path_symlink,
+	.path_mkdir =			apparmor_path_mkdir,
+	.path_rmdir =			apparmor_path_rmdir,
+	.path_mknod =			apparmor_path_mknod,
+	.path_rename =			apparmor_path_rename,
+	.path_chmod =			apparmor_path_chmod,
+	.path_chown =			apparmor_path_chown,
+	.path_truncate =		apparmor_path_truncate,
+	.dentry_open =			apparmor_dentry_open,
+	.inode_getattr =                apparmor_inode_getattr,
+
+	.file_permission =		apparmor_file_permission,
+	.file_alloc_security =		apparmor_file_alloc_security,
+	.file_free_security =		apparmor_file_free_security,
+	.file_mmap =			apparmor_file_mmap,
+	.file_mprotect =		apparmor_file_mprotect,
+	.file_lock =			apparmor_file_lock,
+
+	.getprocattr =			apparmor_getprocattr,
+	.setprocattr =			apparmor_setprocattr,
+
+	.cred_alloc_blank =		apparmor_cred_alloc_blank,
+	.cred_free =			apparmor_cred_free,
+	.cred_prepare =			apparmor_cred_prepare,
+	.cred_transfer =		apparmor_cred_transfer,
+
+	.bprm_set_creds =		apparmor_bprm_set_creds,
+	.bprm_committing_creds =	apparmor_bprm_committing_creds,
+	.bprm_committed_creds =		apparmor_bprm_committed_creds,
+	.bprm_secureexec =		apparmor_bprm_secureexec,
+
+	.task_setrlimit =		apparmor_task_setrlimit,
+};
+
+/*
+ * AppArmor sysfs module parameters
+ */
+
+static int param_set_aabool(const char *val, struct kernel_param *kp);
+static int param_get_aabool(char *buffer, struct kernel_param *kp);
+#define param_check_aabool(name, p) __param_check(name, p, int)
+
+static int param_set_aauint(const char *val, struct kernel_param *kp);
+static int param_get_aauint(char *buffer, struct kernel_param *kp);
+#define param_check_aauint(name, p) __param_check(name, p, int)
+
+static int param_set_aalockpolicy(const char *val, struct kernel_param *kp);
+static int param_get_aalockpolicy(char *buffer, struct kernel_param *kp);
+#define param_check_aalockpolicy(name, p) __param_check(name, p, int)
+
+static int param_set_audit(const char *val, struct kernel_param *kp);
+static int param_get_audit(char *buffer, struct kernel_param *kp);
+#define param_check_audit(name, p) __param_check(name, p, int)
+
+static int param_set_mode(const char *val, struct kernel_param *kp);
+static int param_get_mode(char *buffer, struct kernel_param *kp);
+#define param_check_mode(name, p) __param_check(name, p, int)
+
+/* Flag values, also controllable via /sys/module/apparmor/parameters
+ * We define special types as we want to do additional mediation.
+ */
+
+/* AppArmor global enforcement switch - complain, enforce, kill */
+enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
+module_param_call(mode, param_set_mode, param_get_mode,
+		  &aa_g_profile_mode, S_IRUSR | S_IWUSR);
+
+/* Debug mode */
+int aa_g_debug;
+module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
+
+/* Audit mode */
+enum audit_mode aa_g_audit;
+module_param_call(audit, param_set_audit, param_get_audit,
+		  &aa_g_audit, S_IRUSR | S_IWUSR);
+
+/* Determines if audit header is included in audited messages.  This
+ * provides more context if the audit daemon is not running
+ */
+int aa_g_audit_header = 1;
+module_param_named(audit_header, aa_g_audit_header, aabool,
+		   S_IRUSR | S_IWUSR);
+
+/* lock out loading/removal of policy
+ * TODO: add in at boot loading of policy, which is the only way to
+ *       load policy, if lock_policy is set
+ */
+int aa_g_lock_policy;
+module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
+		   S_IRUSR | S_IWUSR);
+
+/* Syscall logging mode */
+int aa_g_logsyscall;
+module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
+
+/* Maximum pathname length before accesses will start getting rejected */
+unsigned int aa_g_path_max = 2 * PATH_MAX;
+module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
+
+/* Determines how paranoid loading of policy is and how much verification
+ * on the loaded policy is done.
+ */
+int aa_g_paranoid_load = 1;
+module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
+		   S_IRUSR | S_IWUSR);
+
+/* Boot time disable flag */
+static unsigned int apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
+module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR);
+
+static int __init apparmor_enabled_setup(char *str)
+{
+	unsigned long enabled;
+	int error = strict_strtoul(str, 0, &enabled);
+	if (!error)
+		apparmor_enabled = enabled ? 1 : 0;
+	return 1;
+}
+
+__setup("apparmor=", apparmor_enabled_setup);
+
+/* set global flag turning off the ability to load policy */
+static int param_set_aalockpolicy(const char *val, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+	if (aa_g_lock_policy)
+		return -EACCES;
+	return param_set_bool(val, kp);
+}
+
+static int param_get_aalockpolicy(char *buffer, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+	return param_get_bool(buffer, kp);
+}
+
+static int param_set_aabool(const char *val, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+	return param_set_bool(val, kp);
+}
+
+static int param_get_aabool(char *buffer, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+	return param_get_bool(buffer, kp);
+}
+
+static int param_set_aauint(const char *val, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+	return param_set_uint(val, kp);
+}
+
+static int param_get_aauint(char *buffer, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+	return param_get_uint(buffer, kp);
+}
+
+static int param_get_audit(char *buffer, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+
+	if (!apparmor_enabled)
+		return -EINVAL;
+
+	return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
+}
+
+static int param_set_audit(const char *val, struct kernel_param *kp)
+{
+	int i;
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+
+	if (!apparmor_enabled)
+		return -EINVAL;
+
+	if (!val)
+		return -EINVAL;
+
+	for (i = 0; i < AUDIT_MAX_INDEX; i++) {
+		if (strcmp(val, audit_mode_names[i]) == 0) {
+			aa_g_audit = i;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int param_get_mode(char *buffer, struct kernel_param *kp)
+{
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+
+	if (!apparmor_enabled)
+		return -EINVAL;
+
+	return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]);
+}
+
+static int param_set_mode(const char *val, struct kernel_param *kp)
+{
+	int i;
+	if (!capable(CAP_MAC_ADMIN))
+		return -EPERM;
+
+	if (!apparmor_enabled)
+		return -EINVAL;
+
+	if (!val)
+		return -EINVAL;
+
+	for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) {
+		if (strcmp(val, profile_mode_names[i]) == 0) {
+			aa_g_profile_mode = i;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+/*
+ * AppArmor init functions
+ */
+
+/**
+ * set_init_cxt - set a task context and profile on the first task.
+ *
+ * TODO: allow setting an alternate profile than unconfined
+ */
+static int __init set_init_cxt(void)
+{
+	struct cred *cred = (struct cred *)current->real_cred;
+	struct aa_task_cxt *cxt;
+
+	cxt = aa_alloc_task_context(GFP_KERNEL);
+	if (!cxt)
+		return -ENOMEM;
+
+	cxt->profile = aa_get_profile(root_ns->unconfined);
+	cred->security = cxt;
+
+	return 0;
+}
+
+static int __init apparmor_init(void)
+{
+	int error;
+
+	if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
+		aa_info_message("AppArmor disabled by boot time parameter");
+		apparmor_enabled = 0;
+		return 0;
+	}
+
+	error = aa_alloc_root_ns();
+	if (error) {
+		AA_ERROR("Unable to allocate default profile namespace\n");
+		goto alloc_out;
+	}
+
+	error = set_init_cxt();
+	if (error) {
+		AA_ERROR("Failed to set context on init task\n");
+		goto register_security_out;
+	}
+
+	error = register_security(&apparmor_ops);
+	if (error) {
+		AA_ERROR("Unable to register AppArmor\n");
+		goto register_security_out;
+	}
+
+	/* Report that AppArmor successfully initialized */
+	apparmor_initialized = 1;
+	if (aa_g_profile_mode == APPARMOR_COMPLAIN)
+		aa_info_message("AppArmor initialized: complain mode enabled");
+	else if (aa_g_profile_mode == APPARMOR_KILL)
+		aa_info_message("AppArmor initialized: kill mode enabled");
+	else
+		aa_info_message("AppArmor initialized");
+
+	return error;
+
+register_security_out:
+	aa_free_root_ns();
+
+alloc_out:
+	aa_destroy_aafs();
+
+	apparmor_enabled = 0;
+	return error;
+
+}
+
+security_initcall(apparmor_init);