linux_dsm_epyc7002/security/integrity/digsig.c
Dmitry Kasatkin f4dc37785e integrity: define '.evm' as a builtin 'trusted' keyring
Require all keys added to the EVM keyring be signed by an
existing trusted key on the system trusted keyring.

This patch also switches IMA to use integrity_init_keyring().

Changes in v3:
* Added 'init_keyring' config based variable to skip initializing
  keyring instead of using  __integrity_init_keyring() wrapper.
* Added dependency back to CONFIG_IMA_TRUSTED_KEYRING

Changes in v2:
* Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common
  CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option
* Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config
  file compatibility. (Mimi Zohar)

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-11-23 14:30:02 -05:00

131 lines
2.9 KiB
C

/*
* 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/sched.h>
#include <linux/slab.h>
#include <linux/cred.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] = {
#ifndef CONFIG_INTEGRITY_TRUSTED_KEYRING
"_evm",
"_ima",
#else
".evm",
".ima",
#endif
"_module",
};
#ifdef CONFIG_INTEGRITY_TRUSTED_KEYRING
static bool init_keyring __initdata = true;
#else
static bool init_keyring __initdata;
#endif
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\n", keyring_name[id], err);
keyring[id] = NULL;
return err;
}
}
switch (sig[1]) {
case 1:
/* v1 API expect signature without xattr type */
return digsig_verify(keyring[id], sig + 1, siglen - 1,
digest, digestlen);
case 2:
return asymmetric_verify(keyring[id], sig, siglen,
digest, digestlen);
}
return -EOPNOTSUPP;
}
int __init integrity_init_keyring(const unsigned int id)
{
const struct cred *cred = current_cred();
int err = 0;
if (!init_keyring)
return 0;
keyring[id] = keyring_alloc(keyring_name[id], KUIDT_INIT(0),
KGIDT_INIT(0), cred,
((KEY_POS_ALL & ~KEY_POS_SETATTR) |
KEY_USR_VIEW | KEY_USR_READ |
KEY_USR_WRITE | KEY_USR_SEARCH),
KEY_ALLOC_NOT_IN_QUOTA, NULL);
if (!IS_ERR(keyring[id]))
set_bit(KEY_FLAG_TRUSTED_ONLY, &keyring[id]->flags);
else {
err = PTR_ERR(keyring[id]);
pr_info("Can't allocate %s keyring (%d)\n",
keyring_name[id], err);
keyring[id] = NULL;
}
return err;
}
int __init integrity_load_x509(const unsigned int id, const char *path)
{
key_ref_t key;
char *data;
int rc;
if (!keyring[id])
return -EINVAL;
rc = integrity_read_file(path, &data);
if (rc < 0)
return rc;
key = key_create_or_update(make_key_ref(keyring[id], 1),
"asymmetric",
NULL,
data,
rc,
((KEY_POS_ALL & ~KEY_POS_SETATTR) |
KEY_USR_VIEW | KEY_USR_READ),
KEY_ALLOC_NOT_IN_QUOTA);
if (IS_ERR(key)) {
rc = PTR_ERR(key);
pr_err("Problem loading X.509 certificate (%d): %s\n",
rc, path);
} else {
pr_notice("Loaded X.509 cert '%s': %s\n",
key_ref_to_ptr(key)->description, path);
key_ref_put(key);
}
kfree(data);
return 0;
}