diff options
| -rw-r--r-- | crypto/asymmetric_keys/Kconfig | 13 | ||||
| -rw-r--r-- | crypto/asymmetric_keys/Makefile | 7 | ||||
| -rw-r--r-- | crypto/asymmetric_keys/pkcs7_key_type.c | 97 |
3 files changed, 117 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index a7cec9dd6154..b6df198d1b6f 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -46,4 +46,17 @@ config PKCS7_MESSAGE_PARSER This option provides support for parsing PKCS#7 format messages for signature data and provides the ability to verify the signature. +config PKCS7_TEST_KEY + tristate "PKCS#7 testing key type" + depends on PKCS7_MESSAGE_PARSER + select SYSTEM_TRUSTED_KEYRING + help + This option provides a type of key that can be loaded up from a + PKCS#7 message - provided the message is signed by a trusted key. If + it is, the PKCS#7 wrapper is discarded and reading the key returns + just the payload. If it isn't, adding the key will fail with an + error. + + This is intended for testing the PKCS#7 parser. + endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index d63cb4320b96..92d0e9af24d5 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -40,3 +40,10 @@ $(obj)/pkcs7_parser.o: $(obj)/pkcs7-asn1.h $(obj)/pkcs7-asn1.o: $(obj)/pkcs7-asn1.c $(obj)/pkcs7-asn1.h clean-files += pkcs7-asn1.c pkcs7-asn1.h + +# +# PKCS#7 parser testing key +# +obj-$(CONFIG_PKCS7_TEST_KEY) += pkcs7_test_key.o +pkcs7_test_key-y := \ + pkcs7_key_type.o diff --git a/crypto/asymmetric_keys/pkcs7_key_type.c b/crypto/asymmetric_keys/pkcs7_key_type.c new file mode 100644 index 000000000000..b1797d2516e2 --- /dev/null +++ b/crypto/asymmetric_keys/pkcs7_key_type.c @@ -0,0 +1,97 @@ +/* Testing module to load key from trusted PKCS#7 message + * + * Copyright (C) 2014 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) "PKCS7key: "fmt +#include <linux/key.h> +#include <linux/key-type.h> +#include <crypto/pkcs7.h> +#include <keys/user-type.h> +#include <keys/system_keyring.h> +#include "pkcs7_parser.h" + +/* + * Instantiate a PKCS#7 wrapped and validated key. + */ +int pkcs7_instantiate(struct key *key, struct key_preparsed_payload *prep) +{ + struct pkcs7_message *pkcs7; + const void *data, *saved_prep_data; + size_t datalen, saved_prep_datalen; + bool trusted; + int ret; + + kenter(""); + + saved_prep_data = prep->data; + saved_prep_datalen = prep->datalen; + pkcs7 = pkcs7_parse_message(saved_prep_data, saved_prep_datalen); + if (IS_ERR(pkcs7)) { + ret = PTR_ERR(pkcs7); + goto error; + } + + ret = pkcs7_verify(pkcs7); + if (ret < 0) + goto error_free; + + ret = pkcs7_validate_trust(pkcs7, system_trusted_keyring, &trusted); + if (ret < 0) + goto error_free; + if (!trusted) + pr_warn("PKCS#7 message doesn't chain back to a trusted key\n"); + + ret = pkcs7_get_content_data(pkcs7, &data, &datalen, false); + if (ret < 0) + goto error_free; + + prep->data = data; + prep->datalen = datalen; + ret = user_instantiate(key, prep); + prep->data = saved_prep_data; + prep->datalen = saved_prep_datalen; + +error_free: + pkcs7_free_message(pkcs7); +error: + kleave(" = %d", ret); + return ret; +} + +/* + * user defined keys take an arbitrary string as the description and an + * arbitrary blob of data as the payload + */ +struct key_type key_type_pkcs7 = { + .name = "pkcs7_test", + .def_lookup_type = KEYRING_SEARCH_LOOKUP_DIRECT, + .instantiate = pkcs7_instantiate, + .match = user_match, + .revoke = user_revoke, + .destroy = user_destroy, + .describe = user_describe, + .read = user_read, +}; + +/* + * Module stuff + */ +static int __init pkcs7_key_init(void) +{ + return register_key_type(&key_type_pkcs7); +} + +static void __exit pkcs7_key_cleanup(void) +{ + unregister_key_type(&key_type_pkcs7); +} + +module_init(pkcs7_key_init); +module_exit(pkcs7_key_cleanup); |