/*
   * Copyright (C) 2011 Intel Corporation
   *
   * Author:
   * Dmitry Kasatkin <dmitry.kasatkin@intel.com>
   *
   * 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.
   *
   */
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <linux/err.h>
  #include <linux/rbtree.h>
  #include <linux/key-type.h>
  #include <linux/digsig.h>
  
  #include "integrity.h"
  
  static struct key *keyring[INTEGRITY_KEYRING_MAX];
  
  static const char *keyring_name[INTEGRITY_KEYRING_MAX] = {
  	"_evm",
  	"_module",
  	"_ima",
  };
  
  int integrity_digsig_verify(const unsigned int id, const char *sig, int siglen,
  					const char *digest, int digestlen)
  {
  	if (id >= INTEGRITY_KEYRING_MAX)
  		return -EINVAL;
  
  	if (!keyring[id]) {
  		keyring[id] =
  			request_key(&key_type_keyring, keyring_name[id], NULL);
  		if (IS_ERR(keyring[id])) {
  			int err = PTR_ERR(keyring[id]);
  			pr_err("no %s keyring: %d
  ", keyring_name[id], err);
  			keyring[id] = NULL;
  			return err;
  		}
  	}
  
  	return digsig_verify(keyring[id], sig, siglen, digest, digestlen);
  }