security/integrity/platform_certs/platform_keyring.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Platform keyring for firmware/platform keys
   4  *
   5  * Copyright IBM Corporation, 2018
   6  * Author(s): Nayna Jain <nayna@linux.ibm.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/slab.h>
  15 #include "../integrity.h"
  16
  17 static struct key_acl platform_key_acl = {
  18         .usage  = REFCOUNT_INIT(1),
  19         .nr_ace = 2,
  20         .aces = {
  21                 KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_READ),
  22                 KEY_OWNER_ACE(KEY_ACE_VIEW),
  23         }
  24 };
  25
  26 /**
  27  * add_to_platform_keyring - Add to platform keyring without validation.
  28  * @source: Source of key
  29  * @data: The blob holding the key
  30  * @len: The length of the data blob
  31  *
  32  * Add a key to the platform keyring without checking its trust chain.  This
  33  * is available only during kernel initialisation.
  34  */
  35 void __init add_to_platform_keyring(const char *source, const void *data,
  36                                     size_t len)
  37 {
  38         int rc;
  39
  40         rc = integrity_load_cert(INTEGRITY_KEYRING_PLATFORM, source, data, len,
  41                                  &platform_key_acl);
  42         if (rc)
  43                 pr_info("Error adding keys to platform keyring %s\n", source);
  44 }
  45
  46 /*
  47  * Create the trusted keyrings.
  48  */
  49 static __init int platform_keyring_init(void)
  50 {
  51         int rc;
  52
  53         rc = integrity_init_keyring(INTEGRITY_KEYRING_PLATFORM);
  54         if (rc)
  55                 return rc;
  56
  57         pr_notice("Platform Keyring initialized\n");
  58         return 0;
  59 }
  60
  61 /*
  62  * Must be initialised before we try and load the keys into the keyring.
  63  */
  64 device_initcall(platform_keyring_init);