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lsm.c

/*
 * AppArmor security module
 *
 * This file contains AppArmor LSM hooks.
 *
 * Copyright (C) 1998-2008 Novell/SUSE
 * Copyright 2009 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/net.h"
#include "include/path.h"
#include "include/policy.h"
#include "include/procattr.h"

/* Flag indicating whether initialization completed */
int apparmor_initialized;


/*
 * LSM hook functions
 */

/*
 * prepare new aa_task_context for modification by prepare_cred block
 */
static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
                         gfp_t gfp)
{
      struct aa_task_context *cxt = aa_dup_task_context(old->security, gfp);
      if (!cxt)
            return -ENOMEM;
      new->security = cxt;
      return 0;
}

/*
 * free the associated aa_task_context and put its profiles
 */
static void apparmor_cred_free(struct cred *cred)
{
      struct aa_task_context *cxt = cred->security;
      cred->security = NULL;
      aa_free_task_context(cxt);
}


static int apparmor_ptrace_may_access(struct task_struct *child,
                              unsigned int mode)
{
      return aa_ptrace(current, child, mode);
}


static int apparmor_ptrace_traceme(struct task_struct *parent)
{
      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);
      aa_cred_policy(cred, &profile);

      *effective   = cred->cap_effective;
      *inheritable = cred->cap_inheritable;
      *permitted   = cred->cap_permitted;

      if (profile) {
            *effective = cap_combine(*effective, profile->caps.set);
            *effective = cap_intersect(*effective, profile->caps.allowed);
      }
      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);

      aa_cred_policy(cred, &profile);
      if (profile && (!error || cap_raised(profile->caps.set, cap)))
            error = aa_capable(task, profile, cap, audit);

      return error;
}

static int apparmor_sysctl(struct ctl_table *table, int op)
{
      int error = 0;
      struct aa_profile *profile = aa_current_profile_wupd();

      if (profile) {
            char *buffer, *name;
            int mask;

            mask = 0;
            if (op & 4)
                  mask |= MAY_READ;
            if (op & 2)
                  mask |= MAY_WRITE;

            error = -ENOMEM;
            buffer = (char *)__get_free_page(GFP_KERNEL);
            if (!buffer)
                  goto out;

            /* 
             * TODO: convert this over to using a global or per
             * namespace control instead of a hard coded /proc
             */
            name = sysctl_pathname(table, buffer, PAGE_SIZE);
            if (name && name - buffer >= 5) {
                  struct path_cond cond = { 0, S_IFREG };
                  name -= 5;
                  memcpy(name, "/proc", 5);
                  error = aa_pathstr_perm(profile, "sysctl", name, mask,
                                    &cond);
            }
            free_page((unsigned long)buffer);
      }

out:
      return error;
}

static int common_perm(const char *op, struct path *path, u16 mask,
                   struct path_cond *cond)
{
      struct aa_profile *profile;
      int error = 0;

      profile = aa_current_profile();
      if (profile)
            error = aa_path_perm(profile, op, path, mask, cond);

      return error;
}

static int common_perm_dentry(const char *op, struct path *dir,
                        struct dentry *dentry, u16 mask, 
                        struct path_cond *cond)
{
      struct path path = { dir->mnt, dentry };

      return common_perm(op, &path, mask, cond);
}

static int common_perm_rm(const char *op, struct path *dir,
                    struct dentry *dentry, u16 mask)
{
      struct inode *inode = dentry->d_inode;
      struct path_cond cond = {};

      if (!dir->mnt || !inode || !mediated_filesystem(inode))
            return 0;

      cond.uid = inode->i_uid;
      cond.mode = inode->i_mode;

      return common_perm_dentry(op, dir, dentry, mask, &cond);
}

static int common_perm_create(const char *op, struct path *dir,
                        struct dentry *dentry, u16 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_dentry(op, dir, dentry, mask, &cond);
}

static int apparmor_path_unlink(struct path *dir, struct dentry *dentry)
{
      return common_perm_rm("unlink", dir, dentry, MAY_WRITE);
}

static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
                         int mode)
{
      return common_perm_create("mkdir", dir, dentry, AA_MAY_CREATE, S_IFDIR);
}

static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry)
{
      return common_perm_rm("rmdir", dir, dentry, MAY_WRITE);
}

static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
                         int mode, unsigned int dev)
{
      return common_perm_create("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("truncate", path, MAY_WRITE, &cond);
}

static int apparmor_path_symlink(struct path *dir, struct dentry *dentry,
                    const char *old_name)
{
      return common_perm_create("symlink_create", 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_wupd();
      if (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_wupd();
      if (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(profile, "rename_src", &old_path,
                             MAY_READ | MAY_WRITE, &cond);
            if (!error)
                  error = aa_path_perm(profile, "rename_dest", &new_path,
                                   AA_MAY_CREATE | MAY_WRITE, &cond);
                                   
      }
      return error;
}

static int apparmor_dentry_open(struct file *file, const struct cred *cred)
{
      struct aa_profile *profile;
      int error = 0;
        
      /* If in exec permission is handled by bprm hooks */
      if (current->in_execve ||
          !mediated_filesystem(file->f_path.dentry->d_inode))
            return 0;

      aa_cred_policy(cred, &profile);
      if (profile) {
            struct aa_file_cxt *fcxt = file->f_security;
            struct inode *inode = file->f_path.dentry->d_inode; 
            struct path_cond cond = { inode->i_uid, inode->i_mode };

            error = aa_path_perm(profile, "open", &file->f_path,
                             aa_map_file_to_perms(file), &cond);
            fcxt->profile = aa_get_profile(profile);
            /* todo cache actual allowed permissions */
            fcxt->allowed = 0;
      }

      return error;
}

static int apparmor_file_alloc_security(struct file *file)
{
      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 apparmor_file_permission(struct file *file, int mask)
{
      /*
       * Most basic (rw) file access is revalidated at exec.
       * The revalidation done here is for parent/child hat
       * file accesses.
       *
       * Currently profile replacement does not cause revalidation
       * or file revocation.
       *
       * TODO: cache profiles that have revalidated?
       */
      struct aa_file_cxt *fcxt = file->f_security;
      struct aa_profile *profile, *fprofile = fcxt->profile;
      int error = 0;

      if (!fprofile || !file->f_path.mnt ||
          !mediated_filesystem(file->f_path.dentry->d_inode))
            return 0;

      profile = aa_current_profile();
      /* TODO: Enable at exec time revalidation of files
      if (profile && (fprofile != profile) &&
          ((PROFILE_IS_HAT(profile) && (profile->parent == fprofile)) ||
           (PROFILE_IS_HAT(fprofile) && (fprofile->parent == profile))))
            error = aa_file_perm(profile, "file_perm", file, mask);
      */
      if (profile && ((fprofile != profile) || (mask & ~fcxt->allowed)))
            error = aa_file_perm(profile, "file_perm", file, mask);

      return error;
}

static int common_file_perm(const char *op, struct file *file, u16 mask)
{
      const struct aa_file_cxt *fcxt = file->f_security;
      struct aa_profile *profile, *fprofile = fcxt->profile;
      int error = 0;

      if (!fprofile || !file->f_path.mnt ||
          !mediated_filesystem(file->f_path.dentry->d_inode))
            return 0;

      profile = aa_current_profile_wupd();
      if (profile && ((fprofile != profile) || (mask & ~fcxt->allowed)))
            error = aa_file_perm(profile, op, file, mask);

      return error;
}

static int apparmor_file_lock(struct file *file, unsigned int cmd)
{
      u16 mask = AA_MAY_LOCK;

      if (cmd == F_WRLCK)
            mask |= MAY_WRITE;

      return common_file_perm("file_lock", file, mask);
}


/*
 * AppArmor doesn't current use the fcntl hook.
 * 
 * FIXME - these are not implemented yet - REMOVE file_fcntl hook
 * NOTE: some of the file control commands are further mediated
 *       by other hooks
 * F_SETOWN - security_file_set_fowner
 * F_SETLK - security_file_lock
 * F_SETLKW - security_file_lock
 * O_APPEND - AppArmor mediates append as a subset of full write
 *            so changing from full write to appending write is
 *            dropping priviledge and not restricted.


static int apparmor_file_fcntl(struct file *file, unsigned int cmd,
                       unsigned long arg)
{
      return 0;
}
*/

static int common_mmap(struct file *file, const char *operation,
               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(operation, 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)
{
      if ((addr < mmap_min_addr) && !capable(CAP_SYS_RAWIO)) {
            struct aa_profile *profile = aa_current_profile_wupd();
            if (profile)
                  /* future control check here */
                  return -EACCES;
            else
                  return -EACCES;
      }

      return common_mmap(file, "file_mmap", prot, flags);
}

static int apparmor_file_mprotect(struct vm_area_struct *vma,
                          unsigned long reqprot, unsigned long prot)
{
      return common_mmap(vma->vm_file, "file_mprotect", 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_namespace *ns;
      struct aa_profile *profile, *onexec, *prev;
      const struct cred *cred = aa_get_task_policy(task, &profile);
      struct aa_task_context *cxt = cred->security;
      ns = cxt->sys.profile->ns;
      onexec = cxt->sys.onexec;
      prev = cxt->sys.previous;

      /* task must be either querying itself, unconfined or can ptrace */
      if (current != task && profile && !capable(CAP_SYS_PTRACE)) {
            error = -EPERM;
      } else {
            if (strcmp(name, "current") == 0) {
                  error = aa_getprocattr(ns, profile, value);
            } else if (strcmp(name, "prev") == 0) {
                  if (prev)
                        error = aa_getprocattr(ns, prev, value);
            } else if (strcmp(name, "exec") == 0) {
                  if (onexec)
                        error = aa_getprocattr(ns, 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;
      int error;

      if (size == 0 || size >= PAGE_SIZE)
            return -EINVAL;

      /* task can only write its own attributes */
      if (current != task)
            return -EACCES;

      args = value;
      args[size] = '\0';
      args = strstrip(args);
      command = strsep(&args, " ");
      if (!args)
            return -EINVAL;
      while (isspace(*args))
            args++;
      if (!*args)
            return -EINVAL;

      if (strcmp(name, "current") == 0) {
            if (strcmp(command, "changehat") == 0) {
                  error = aa_setprocattr_changehat(args, !AA_DO_TEST);
            } else if (strcmp(command, "permhat") == 0) {
                  error = aa_setprocattr_changehat(args, AA_DO_TEST);
            } else if (strcmp(command, "changeprofile") == 0) {
                  error = aa_setprocattr_changeprofile(args, 0,
                                               !AA_DO_TEST);
            } else if (strcmp(command, "permprofile") == 0) {
                  error = aa_setprocattr_changeprofile(args, 0,
                                               AA_DO_TEST);
            } else if (strcmp(command, "permipc") == 0) {
                  error = aa_setprocattr_permipc(args);
            } else {
                  struct aa_audit sa;
                  memset(&sa, 0, sizeof(sa));
                  sa.operation = "setprocattr";
                  sa.gfp_mask = GFP_KERNEL;
                  sa.info = name;
                  sa.error = -EINVAL;
                  return aa_audit(AUDIT_APPARMOR_DENIED, NULL, &sa, NULL);
            }
      } else if (strcmp(name, "exec") == 0) {
            error = aa_setprocattr_changeprofile(strstrip(args), 1,
                                         !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_wupd();
      int error = 0;

      if (profile) {
            error = aa_task_setrlimit(profile, resource, new_rlim);
      }

      return error;
}

#ifdef CONFIG_SECURITY_APPARMOR_NETWORK
static int apparmor_socket_create(int family, int type, int protocol, int kern){
      struct aa_profile *profile;
      int error = 0;

      if (kern)
            return 0;

      profile = aa_current_profile();
      if (profile)
            error = aa_net_perm(profile, "socket_create", family,
                                          type, protocol);
      return error;
}

static int apparmor_socket_post_create(struct socket *sock, int family,
                              int type, int protocol, int kern)
{
      struct sock *sk = sock->sk;

      if (kern)
            return 0;

      return aa_revalidate_sk(sk, "socket_post_create");
}

static int apparmor_socket_bind(struct socket *sock,
                        struct sockaddr *address, int addrlen)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_bind");
}

static int apparmor_socket_connect(struct socket *sock,
                              struct sockaddr *address, int addrlen)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_connect");
}

static int apparmor_socket_listen(struct socket *sock, int backlog)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_listen");
}

static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_accept");
}

static int apparmor_socket_sendmsg(struct socket *sock,
                              struct msghdr *msg, int size)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_sendmsg");
}

static int apparmor_socket_recvmsg(struct socket *sock,
                           struct msghdr *msg, int size, int flags)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_recvmsg");
}

static int apparmor_socket_getsockname(struct socket *sock)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_getsockname");
}

static int apparmor_socket_getpeername(struct socket *sock)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_getpeername");
}

static int apparmor_socket_getsockopt(struct socket *sock, int level,
                              int optname)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_getsockopt");
}

static int apparmor_socket_setsockopt(struct socket *sock, int level,
                              int optname)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_setsockopt");
}

static int apparmor_socket_shutdown(struct socket *sock, int how)
{
      struct sock *sk = sock->sk;

      return aa_revalidate_sk(sk, "socket_shutdown");
}
#endif

static struct security_operations apparmor_ops = {
      .name =                       "apparmor",

      .ptrace_may_access =          apparmor_ptrace_may_access,
      .ptrace_traceme =       apparmor_ptrace_traceme,
      .capget =               apparmor_capget,
      .sysctl =               apparmor_sysctl,
      .capable =              apparmor_capable,
/*
      .inode_create =               apparmor_inode_create,
      .inode_setattr =        apparmor_inode_setattr,
      .inode_setxattr =       apparmor_inode_setxattr,
      .inode_getxattr =       apparmor_inode_getxattr,
      .inode_listxattr =            apparmor_inode_listxattr,
      .inode_removexattr =          apparmor_inode_removexattr,
      .inode_permission = ??? use to mediate owner access to non-mediated fs
*/

      .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_truncate =        apparmor_path_truncate,
      .dentry_open =                apparmor_dentry_open,

      .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,

/*    .file_fcntl =                 apparmor_file_fcntl, */

      .getprocattr =                apparmor_getprocattr,
      .setprocattr =                apparmor_setprocattr,

#ifdef CONFIG_SECURITY_APPARMOR_NETWORK
      .socket_create =        apparmor_socket_create,
      .socket_post_create =         apparmor_socket_post_create,
      .socket_bind =                apparmor_socket_bind,
      .socket_connect =       apparmor_socket_connect,
      .socket_listen =        apparmor_socket_listen,
      .socket_accept =        apparmor_socket_accept,
      .socket_sendmsg =       apparmor_socket_sendmsg,
      .socket_recvmsg =       apparmor_socket_recvmsg,
      .socket_getsockname =         apparmor_socket_getsockname,
      .socket_getpeername =         apparmor_socket_getpeername,
      .socket_getsockopt =          apparmor_socket_getsockopt,
      .socket_setsockopt =          apparmor_socket_setsockopt,
      .socket_shutdown =            apparmor_socket_shutdown,
#endif

      .cred_free =                  apparmor_cred_free,
      .cred_prepare =               apparmor_cred_prepare,

      .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 g_profile_mode = APPARMOR_ENFORCE;
module_param_call(mode, param_set_mode, param_get_mode,
              &g_profile_mode, S_IRUSR | S_IWUSR);

/* Debug mode */
int g_apparmor_debug;
module_param_named(debug, g_apparmor_debug, aabool, S_IRUSR | S_IWUSR);

/* Audit mode */
enum audit_mode g_apparmor_audit;
module_param_call(audit, param_set_audit, param_get_audit,
              &g_apparmor_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 g_apparmor_audit_header;
module_param_named(audit_header, g_apparmor_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 g_apparmor_lock_policy;
module_param_named(lock_policy, g_apparmor_lock_policy, aalockpolicy,
               S_IRUSR | S_IWUSR);

/* Syscall logging mode */
int g_apparmor_logsyscall;
module_param_named(logsyscall, g_apparmor_logsyscall, aabool,
               S_IRUSR | S_IWUSR);

/* Maximum pathname length before accesses will start getting rejected */
unsigned int g_apparmor_path_max = 2 * PATH_MAX;
module_param_named(path_max, g_apparmor_path_max, aauint, S_IRUSR | S_IWUSR);

/* Boot time disable flag */
#ifdef CONFIG_SECURITY_APPARMOR_DISABLE
#define AA_ENABLED_PERMS 0600
#else
#define AA_ENABLED_PERMS 0400
#endif
static int param_set_aa_enabled(const char *val, struct kernel_param *kp);
static unsigned int apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
module_param_call(enabled, param_set_aa_enabled, param_get_aauint,
              &apparmor_enabled, AA_ENABLED_PERMS);

static int __init apparmor_enabled_setup(char *str)
{
      apparmor_enabled = simple_strtol(str, NULL, 0);
      return 1;
}
__setup("apparmor=", apparmor_enabled_setup);

static int param_set_aalockpolicy(const char *val, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;
      if (g_apparmor_lock_policy)
            return -EACCES;
      return param_set_bool(val, kp);
}

static int param_get_aalockpolicy(char *buffer, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;
      return param_get_bool(buffer, kp);
}

static int param_set_aabool(const char *val, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;
      return param_set_bool(val, kp);
}

static int param_get_aabool(char *buffer, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;
      return param_get_bool(buffer, kp);
}

static int param_set_aauint(const char *val, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;
      return param_set_uint(val, kp);
}

static int param_get_aauint(char *buffer, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;
      return param_get_uint(buffer, kp);
}

/* allow run time disabling of apparmor */
static int param_set_aa_enabled(const char *val, struct kernel_param *kp)
{
      unsigned long l;

      if (!apparmor_initialized) {
            apparmor_enabled = 0;
            return 0;
      }

      if (__aa_task_is_confined(current))
            return -EPERM;

      if (!apparmor_enabled)
            return -EINVAL;

      if (!val)
            return -EINVAL;

      if (strict_strtoul(val, 0, &l) || l != 0)
            return -EINVAL;

      apparmor_enabled = 0;
      apparmor_disable();
      return 0;
}

static int param_get_audit(char *buffer, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;

      if (!apparmor_enabled)
            return -EINVAL;

      return sprintf(buffer, "%s", audit_mode_names[g_apparmor_audit]);
}

static int param_set_audit(const char *val, struct kernel_param *kp)
{
      int i;
      if (__aa_task_is_confined(current))
            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) {
                  g_apparmor_audit = i;
                  return 0;
            }
      }

      return -EINVAL;
}

static int param_get_mode(char *buffer, struct kernel_param *kp)
{
      if (__aa_task_is_confined(current))
            return -EPERM;

      if (!apparmor_enabled)
            return -EINVAL;

      return sprintf(buffer, "%s", profile_mode_names[g_profile_mode]);
}

static int param_set_mode(const char *val, struct kernel_param *kp)
{
      int i;
      if (__aa_task_is_confined(current))
            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) {
                  g_profile_mode = i;
                  return 0;
            }
      }

      return -EINVAL;
}


/*
 * AppArmor init functions
 */

static int set_init_cxt(void)
{
      struct cred *cred = (struct cred *) current->real_cred;
      struct aa_task_context *cxt;

      cxt = aa_alloc_task_context(GFP_KERNEL);
      if (!cxt)
            return -ENOMEM;

      cxt->sys.profile = aa_get_profile(default_namespace->unconfined);
      cred->security = cxt;

      return 0;
}

static int __init apparmor_init(void)
{
      int error;

      if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
            info_message("AppArmor disabled by boot time parameter\n");
            apparmor_enabled = 0;
            return 0;
      }

      /*
       * Activated with fs_initcall
      error = create_apparmorfs();
      if (error) {
            AA_ERROR("Unable to activate AppArmor filesystem\n");
            goto createfs_out;
      }
      */

      error = alloc_default_namespace();
      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 alloc_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 (g_profile_mode == APPARMOR_COMPLAIN)
            info_message("AppArmor initialized: complain mode enabled");
      else if (g_profile_mode == APPARMOR_KILL)
            info_message("AppArmor initialized: kill mode enabled");
      else
            info_message("AppArmor initialized");

      return error;

register_security_out:
      free_default_namespace();

alloc_out:
      destroy_apparmorfs();

/*createfs_out:*/
      apparmor_enabled = 0;
      return error;

}

security_initcall(apparmor_init);

void apparmor_disable(void)
{
      /* Remove and release all the profiles on the profile list. */
      aa_profile_ns_list_release();

      /* FIXME: cleanup profiles references on files */
      free_default_namespace();

      /*
       * Delay for an rcu cycle to make sure that all active task
       * context readers have finished, and all profiles have been
       * freed by their rcu callbacks.
       */
      synchronize_rcu();
      destroy_apparmorfs();
      apparmor_initialized = 0;

      info_message("AppArmor protection disabled");
}


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