security/integrity/ima/ima_mok.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2015 Juniper Networks, Inc.
   4  *
   5  * Author:
   6  * Petko Manolov <petko.manolov@konsulko.com>
   7  */
   8
   9 #include <linux/export.h>
  10 #include <linux/kernel.h>
  11 #include <linux/sched.h>
  12 #include <linux/cred.h>
  13 #include <linux/err.h>
  14 #include <linux/init.h>
  15 #include <linux/slab.h>
  16 #include <keys/system_keyring.h>
  17
  18
  19 static struct key_acl integrity_blacklist_keyring_acl = {
  20         .usage  = REFCOUNT_INIT(1),
  21         .nr_ace = 2,
  22         .aces = {
  23                 KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE),
  24                 KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_WRITE | KEY_ACE_SEARCH),
  25         }
  26 };
  27
  28 struct key *ima_blacklist_keyring;
  29
  30 /*
  31  * Allocate the IMA blacklist keyring
  32  */
  33 __init int ima_mok_init(void)
  34 {
  35         struct key_restriction *restriction;
  36
  37         pr_notice("Allocating IMA blacklist keyring.\n");
  38
  39         restriction = kzalloc(sizeof(struct key_restriction), GFP_KERNEL);
  40         if (!restriction)
  41                 panic("Can't allocate IMA blacklist restriction.");
  42
  43         restriction->check = restrict_link_by_builtin_trusted;
  44
  45         ima_blacklist_keyring = keyring_alloc(".ima_blacklist",
  46                                 KUIDT_INIT(0), KGIDT_INIT(0), current_cred(),
  47                                 &integrity_blacklist_keyring_acl,
  48                                 KEY_ALLOC_NOT_IN_QUOTA,
  49                                 restriction, NULL);
  50
  51         if (IS_ERR(ima_blacklist_keyring))
  52                 panic("Can't allocate IMA blacklist keyring.");
  53
  54         set_bit(KEY_FLAG_KEEP, &ima_blacklist_keyring->flags);
  55         return 0;
  56 }
  57 device_initcall(ima_mok_init);