diff --git a/crypto/Kconfig b/crypto/Kconfig index a3238051b03e..1ca0b246f29f 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1043,5 +1043,6 @@ config CRYPTO_USER_API_SKCIPHER key cipher algorithms. source "drivers/crypto/Kconfig" +source crypto/asymmetric_keys/Kconfig endif # if CRYPTO diff --git a/crypto/Makefile b/crypto/Makefile index 30f33d675330..ced472e18fc3 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -96,3 +96,4 @@ obj-$(CONFIG_CRYPTO_USER_API_SKCIPHER) += algif_skcipher.o # obj-$(CONFIG_XOR_BLOCKS) += xor.o obj-$(CONFIG_ASYNC_CORE) += async_tx/ +obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys/ diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig new file mode 100644 index 000000000000..cad29b3efa0e --- /dev/null +++ b/crypto/asymmetric_keys/Kconfig @@ -0,0 +1,13 @@ +menuconfig ASYMMETRIC_KEY_TYPE + tristate "Asymmetric (public-key cryptographic) key type" + depends on KEYS + help + This option provides support for a key type that holds the data for + the asymmetric keys used for public key cryptographic operations such + as encryption, decryption, signature generation and signature + verification. + +if ASYMMETRIC_KEY_TYPE + + +endif # ASYMMETRIC_KEY_TYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile new file mode 100644 index 000000000000..b725bcce4cfd --- /dev/null +++ b/crypto/asymmetric_keys/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for asymmetric cryptographic keys +# + +obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o + +asymmetric_keys-y := asymmetric_type.o diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h new file mode 100644 index 000000000000..515b63430812 --- /dev/null +++ b/crypto/asymmetric_keys/asymmetric_keys.h @@ -0,0 +1,15 @@ +/* Internal definitions for asymmetric key type + * + * 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. + */ + +static inline const char *asymmetric_key_id(const struct key *key) +{ + return key->type_data.p[1]; +} diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c new file mode 100644 index 000000000000..bfb0424026aa --- /dev/null +++ b/crypto/asymmetric_keys/asymmetric_type.c @@ -0,0 +1,156 @@ +/* Asymmetric public-key cryptography key type + * + * See Documentation/security/asymmetric-keys.txt + * + * 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. + */ +#include +#include +#include +#include +#include "asymmetric_keys.h" + +MODULE_LICENSE("GPL"); + +/* + * Match asymmetric keys on (part of) their name + * We have some shorthand methods for matching keys. We allow: + * + * "" - request a key by description + * "id:" - request a key matching the ID + * ":" - request a key of a subtype + */ +static int asymmetric_key_match(const struct key *key, const void *description) +{ + const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); + const char *spec = description; + const char *id, *kid; + ptrdiff_t speclen; + size_t idlen, kidlen; + + if (!subtype || !spec || !*spec) + return 0; + + /* See if the full key description matches as is */ + if (key->description && strcmp(key->description, description) == 0) + return 1; + + /* All tests from here on break the criterion description into a + * specifier, a colon and then an identifier. + */ + id = strchr(spec, ':'); + if (!id) + return 0; + + speclen = id - spec; + id++; + + /* Anything after here requires a partial match on the ID string */ + kid = asymmetric_key_id(key); + if (!kid) + return 0; + + idlen = strlen(id); + kidlen = strlen(kid); + if (idlen > kidlen) + return 0; + + kid += kidlen - idlen; + if (strcasecmp(id, kid) != 0) + return 0; + + if (speclen == 2 && + memcmp(spec, "id", 2) == 0) + return 1; + + if (speclen == subtype->name_len && + memcmp(spec, subtype->name, speclen) == 0) + return 1; + + return 0; +} + +/* + * Describe the asymmetric key + */ +static void asymmetric_key_describe(const struct key *key, struct seq_file *m) +{ + const struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); + const char *kid = asymmetric_key_id(key); + size_t n; + + seq_puts(m, key->description); + + if (subtype) { + seq_puts(m, ": "); + subtype->describe(key, m); + + if (kid) { + seq_putc(m, ' '); + n = strlen(kid); + if (n <= 8) + seq_puts(m, kid); + else + seq_puts(m, kid + n - 8); + } + + seq_puts(m, " ["); + /* put something here to indicate the key's capabilities */ + seq_putc(m, ']'); + } +} + +/* + * Instantiate a asymmetric_key defined key. The key was preparsed, so we just + * have to transfer the data here. + */ +static int asymmetric_key_instantiate(struct key *key, struct key_preparsed_payload *prep) +{ + return -EOPNOTSUPP; +} + +/* + * dispose of the data dangling from the corpse of a asymmetric key + */ +static void asymmetric_key_destroy(struct key *key) +{ + struct asymmetric_key_subtype *subtype = asymmetric_key_subtype(key); + if (subtype) { + subtype->destroy(key->payload.data); + module_put(subtype->owner); + key->type_data.p[0] = NULL; + } + kfree(key->type_data.p[1]); + key->type_data.p[1] = NULL; +} + +struct key_type key_type_asymmetric = { + .name = "asymmetric", + .instantiate = asymmetric_key_instantiate, + .match = asymmetric_key_match, + .destroy = asymmetric_key_destroy, + .describe = asymmetric_key_describe, +}; +EXPORT_SYMBOL_GPL(key_type_asymmetric); + +/* + * Module stuff + */ +static int __init asymmetric_key_init(void) +{ + return register_key_type(&key_type_asymmetric); +} + +static void __exit asymmetric_key_cleanup(void) +{ + unregister_key_type(&key_type_asymmetric); +} + +module_init(asymmetric_key_init); +module_exit(asymmetric_key_cleanup); diff --git a/include/keys/asymmetric-subtype.h b/include/keys/asymmetric-subtype.h new file mode 100644 index 000000000000..4b840e822209 --- /dev/null +++ b/include/keys/asymmetric-subtype.h @@ -0,0 +1,55 @@ +/* Asymmetric public-key cryptography key subtype + * + * See Documentation/security/asymmetric-keys.txt + * + * 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. + */ + +#ifndef _KEYS_ASYMMETRIC_SUBTYPE_H +#define _KEYS_ASYMMETRIC_SUBTYPE_H + +#include +#include + +struct public_key_signature; + +/* + * Keys of this type declare a subtype that indicates the handlers and + * capabilities. + */ +struct asymmetric_key_subtype { + struct module *owner; + const char *name; + unsigned short name_len; /* length of name */ + + /* Describe a key of this subtype for /proc/keys */ + void (*describe)(const struct key *key, struct seq_file *m); + + /* Destroy a key of this subtype */ + void (*destroy)(void *payload); + + /* Verify the signature on a key of this subtype (optional) */ + int (*verify_signature)(const struct key *key, + const struct public_key_signature *sig); +}; + +/** + * asymmetric_key_subtype - Get the subtype from an asymmetric key + * @key: The key of interest. + * + * Retrieves and returns the subtype pointer of the asymmetric key from the + * type-specific data attached to the key. + */ +static inline +struct asymmetric_key_subtype *asymmetric_key_subtype(const struct key *key) +{ + return key->type_data.p[0]; +} + +#endif /* _KEYS_ASYMMETRIC_SUBTYPE_H */ diff --git a/include/keys/asymmetric-type.h b/include/keys/asymmetric-type.h new file mode 100644 index 000000000000..7dd473496180 --- /dev/null +++ b/include/keys/asymmetric-type.h @@ -0,0 +1,25 @@ +/* Asymmetric Public-key cryptography key type interface + * + * See Documentation/security/asymmetric-keys.txt + * + * 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. + */ + +#ifndef _KEYS_ASYMMETRIC_TYPE_H +#define _KEYS_ASYMMETRIC_TYPE_H + +#include + +extern struct key_type key_type_asymmetric; + +/* + * The payload is at the discretion of the subtype. + */ + +#endif /* _KEYS_ASYMMETRIC_TYPE_H */