diff options
author | David Howells <dhowells@redhat.com> | 2016-04-06 16:14:26 +0100 |
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committer | David Howells <dhowells@redhat.com> | 2016-04-11 22:42:55 +0100 |
commit | cfb664ff2b71fbbdc438b8e6db2a1412440432a2 (patch) | |
tree | 8a57e6e577376339a77c61bfaa83fdce5252319e /crypto/asymmetric_keys | |
parent | 5f7f5c81e59be5ce262c5b7d0ede9565a2558d80 (diff) | |
download | linux-stable-cfb664ff2b71fbbdc438b8e6db2a1412440432a2.tar.gz linux-stable-cfb664ff2b71fbbdc438b8e6db2a1412440432a2.tar.bz2 linux-stable-cfb664ff2b71fbbdc438b8e6db2a1412440432a2.zip |
X.509: Move the trust validation code out to its own file
Move the X.509 trust validation code out to its own file so that it can be
generalised.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'crypto/asymmetric_keys')
-rw-r--r-- | crypto/asymmetric_keys/Makefile | 5 | ||||
-rw-r--r-- | crypto/asymmetric_keys/restrict.c | 106 | ||||
-rw-r--r-- | crypto/asymmetric_keys/x509_parser.h | 6 | ||||
-rw-r--r-- | crypto/asymmetric_keys/x509_public_key.c | 79 |
4 files changed, 116 insertions, 80 deletions
diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index f90486256f01..6516855bec18 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -4,7 +4,10 @@ obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o -asymmetric_keys-y := asymmetric_type.o signature.o +asymmetric_keys-y := \ + asymmetric_type.o \ + restrict.o \ + signature.o obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c new file mode 100644 index 000000000000..b4c10f2f5034 --- /dev/null +++ b/crypto/asymmetric_keys/restrict.c @@ -0,0 +1,106 @@ +/* Instantiate a public key crypto key from an X.509 Certificate + * + * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#define pr_fmt(fmt) "X.509: "fmt +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/mpi.h> +#include <linux/asn1_decoder.h> +#include <keys/asymmetric-subtype.h> +#include <keys/asymmetric-parser.h> +#include <keys/system_keyring.h> +#include <crypto/hash.h> +#include <crypto/public_key.h> +#include "asymmetric_keys.h" +#include "x509_parser.h" + +static bool use_builtin_keys; +static struct asymmetric_key_id *ca_keyid; + +#ifndef MODULE +static struct { + struct asymmetric_key_id id; + unsigned char data[10]; +} cakey; + +static int __init ca_keys_setup(char *str) +{ + if (!str) /* default system keyring */ + return 1; + + if (strncmp(str, "id:", 3) == 0) { + struct asymmetric_key_id *p = &cakey.id; + size_t hexlen = (strlen(str) - 3) / 2; + int ret; + + if (hexlen == 0 || hexlen > sizeof(cakey.data)) { + pr_err("Missing or invalid ca_keys id\n"); + return 1; + } + + ret = __asymmetric_key_hex_to_key_id(str + 3, p, hexlen); + if (ret < 0) + pr_err("Unparsable ca_keys id hex string\n"); + else + ca_keyid = p; /* owner key 'id:xxxxxx' */ + } else if (strcmp(str, "builtin") == 0) { + use_builtin_keys = true; + } + + return 1; +} +__setup("ca_keys=", ca_keys_setup); +#endif + +/* + * Check the new certificate against the ones in the trust keyring. If one of + * those is the signing key and validates the new certificate, then mark the + * new certificate as being trusted. + * + * Return 0 if the new certificate was successfully validated, 1 if we couldn't + * find a matching parent certificate in the trusted list and an error if there + * is a matching certificate but the signature check fails. + */ +int x509_validate_trust(struct x509_certificate *cert, + struct key *trust_keyring) +{ + struct public_key_signature *sig = cert->sig; + struct key *key; + int ret = 1; + + if (!sig->auth_ids[0] && !sig->auth_ids[1]) + return 1; + + if (!trust_keyring) + return -EOPNOTSUPP; + if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid)) + return -EPERM; + if (cert->unsupported_sig) + return -ENOPKG; + + key = find_asymmetric_key(trust_keyring, + sig->auth_ids[0], sig->auth_ids[1], + false); + if (IS_ERR(key)) + return PTR_ERR(key); + + if (!use_builtin_keys || + test_bit(KEY_FLAG_BUILTIN, &key->flags)) { + ret = verify_signature(key, cert->sig); + if (ret == -ENOPKG) + cert->unsupported_sig = true; + } + key_put(key); + return ret; +} +EXPORT_SYMBOL_GPL(x509_validate_trust); diff --git a/crypto/asymmetric_keys/x509_parser.h b/crypto/asymmetric_keys/x509_parser.h index 05eef1c68881..7a802b09a509 100644 --- a/crypto/asymmetric_keys/x509_parser.h +++ b/crypto/asymmetric_keys/x509_parser.h @@ -58,3 +58,9 @@ extern int x509_decode_time(time64_t *_t, size_t hdrlen, */ extern int x509_get_sig_params(struct x509_certificate *cert); extern int x509_check_for_self_signed(struct x509_certificate *cert); + +/* + * public_key_trust.c + */ +extern int x509_validate_trust(struct x509_certificate *cert, + struct key *trust_keyring); diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c index 117a6ee71a4d..6d7f42f0de9a 100644 --- a/crypto/asymmetric_keys/x509_public_key.c +++ b/crypto/asymmetric_keys/x509_public_key.c @@ -20,44 +20,6 @@ #include "asymmetric_keys.h" #include "x509_parser.h" -static bool use_builtin_keys; -static struct asymmetric_key_id *ca_keyid; - -#ifndef MODULE -static struct { - struct asymmetric_key_id id; - unsigned char data[10]; -} cakey; - -static int __init ca_keys_setup(char *str) -{ - if (!str) /* default system keyring */ - return 1; - - if (strncmp(str, "id:", 3) == 0) { - struct asymmetric_key_id *p = &cakey.id; - size_t hexlen = (strlen(str) - 3) / 2; - int ret; - - if (hexlen == 0 || hexlen > sizeof(cakey.data)) { - pr_err("Missing or invalid ca_keys id\n"); - return 1; - } - - ret = __asymmetric_key_hex_to_key_id(str + 3, p, hexlen); - if (ret < 0) - pr_err("Unparsable ca_keys id hex string\n"); - else - ca_keyid = p; /* owner key 'id:xxxxxx' */ - } else if (strcmp(str, "builtin") == 0) { - use_builtin_keys = true; - } - - return 1; -} -__setup("ca_keys=", ca_keys_setup); -#endif - /* * Set up the signature parameters in an X.509 certificate. This involves * digesting the signed data and extracting the signature. @@ -188,47 +150,6 @@ not_self_signed: } /* - * Check the new certificate against the ones in the trust keyring. If one of - * those is the signing key and validates the new certificate, then mark the - * new certificate as being trusted. - * - * Return 0 if the new certificate was successfully validated, 1 if we couldn't - * find a matching parent certificate in the trusted list and an error if there - * is a matching certificate but the signature check fails. - */ -static int x509_validate_trust(struct x509_certificate *cert, - struct key *trust_keyring) -{ - struct public_key_signature *sig = cert->sig; - struct key *key; - int ret = 1; - - if (!sig->auth_ids[0] && !sig->auth_ids[1]) - return 1; - - if (!trust_keyring) - return -EOPNOTSUPP; - if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid)) - return -EPERM; - if (cert->unsupported_sig) - return -ENOPKG; - - key = find_asymmetric_key(trust_keyring, - sig->auth_ids[0], sig->auth_ids[1], false); - if (IS_ERR(key)) - return PTR_ERR(key); - - if (!use_builtin_keys || - test_bit(KEY_FLAG_BUILTIN, &key->flags)) { - ret = verify_signature(key, cert->sig); - if (ret == -ENOPKG) - cert->unsupported_sig = true; - } - key_put(key); - return ret; -} - -/* * Attempt to parse a data blob for a key as an X509 certificate. */ static int x509_key_preparse(struct key_preparsed_payload *prep) |