diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index 5ed46eecb299..8dcdf0cdb261 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -4,6 +4,6 @@ obj-$(CONFIG_ASYMMETRIC_KEY_TYPE) += asymmetric_keys.o -asymmetric_keys-y := asymmetric_type.o +asymmetric_keys-y := asymmetric_type.o signature.o obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o diff --git a/crypto/asymmetric_keys/signature.c b/crypto/asymmetric_keys/signature.c new file mode 100644 index 000000000000..50b3f880b4ff --- /dev/null +++ b/crypto/asymmetric_keys/signature.c @@ -0,0 +1,49 @@ +/* Signature verification with an asymmetric key + * + * 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" + +/** + * verify_signature - Initiate the use of an asymmetric key to verify a signature + * @key: The asymmetric key to verify against + * @sig: The signature to check + * + * Returns 0 if successful or else an error. + */ +int verify_signature(const struct key *key, + const struct public_key_signature *sig) +{ + const struct asymmetric_key_subtype *subtype; + int ret; + + pr_devel("==>%s()\n", __func__); + + if (key->type != &key_type_asymmetric) + return -EINVAL; + subtype = asymmetric_key_subtype(key); + if (!subtype || + !key->payload.data) + return -EINVAL; + if (!subtype->verify_signature) + return -ENOTSUPP; + + ret = subtype->verify_signature(key, sig); + + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_signature); diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h index 4b8b6c16eac6..f5b0224c9967 100644 --- a/include/crypto/public_key.h +++ b/include/crypto/public_key.h @@ -101,4 +101,8 @@ struct public_key_signature { }; }; +struct key; +extern int verify_signature(const struct key *key, + const struct public_key_signature *sig); + #endif /* _LINUX_PUBLIC_KEY_H */