From 6862128151fb78f63685a8da5575783c426d64a7 Mon Sep 17 00:00:00 2001 From: Martin Willi Date: Wed, 5 Apr 2006 12:10:50 +0000 Subject: ../svn-commit.tmp --- Source/lib/crypto/signers/hmac_signer.c | 168 ++++++++++++++++++++++++++++++++ 1 file changed, 168 insertions(+) create mode 100644 Source/lib/crypto/signers/hmac_signer.c (limited to 'Source/lib/crypto/signers/hmac_signer.c') diff --git a/Source/lib/crypto/signers/hmac_signer.c b/Source/lib/crypto/signers/hmac_signer.c new file mode 100644 index 000000000..e4311da1b --- /dev/null +++ b/Source/lib/crypto/signers/hmac_signer.c @@ -0,0 +1,168 @@ +/** + * @file hmac_signer.c + * + * @brief Implementation of hmac_signer_t. + * + */ + +/* + * Copyright (C) 2005 Jan Hutter, Martin Willi + * Hochschule fuer Technik Rapperswil + * + * 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; either version 2 of the License, or (at your + * option) any later version. See . + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + */ + +#include "hmac_signer.h" + +#include +#include + +/** + * This class represents a hmac signer with 12 byte (96 bit) output. + */ +#define BLOCK_SIZE 12 + +typedef struct private_hmac_signer_t private_hmac_signer_t; + +/** + * Private data structure with signing context. + */ +struct private_hmac_signer_t { + /** + * Public interface of hmac_signer_t. + */ + hmac_signer_t public; + + /* + * Assigned hmac function. + */ + prf_t *hmac_prf; +}; + +/** + * Implementation of signer_t.get_signature. + */ +static void get_signature (private_hmac_signer_t *this, chunk_t data, u_int8_t *buffer) +{ + u_int8_t full_mac[this->hmac_prf->get_block_size(this->hmac_prf)]; + + this->hmac_prf->get_bytes(this->hmac_prf,data,full_mac); + + /* copy mac aka signature :-) */ + memcpy(buffer,full_mac,BLOCK_SIZE); +} + +/** + * Implementation of signer_t.allocate_signature. + */ +static void allocate_signature (private_hmac_signer_t *this, chunk_t data, chunk_t *chunk) +{ + chunk_t signature; + u_int8_t full_mac[this->hmac_prf->get_block_size(this->hmac_prf)]; + + this->hmac_prf->get_bytes(this->hmac_prf,data,full_mac); + + signature.ptr = allocator_alloc(BLOCK_SIZE); + signature.len = BLOCK_SIZE; + + /* copy signature */ + memcpy(signature.ptr,full_mac,BLOCK_SIZE); + + *chunk = signature; +} + +/** + * Implementation of signer_t.verify_signature. + */ +static bool verify_signature (private_hmac_signer_t *this, chunk_t data, chunk_t signature) +{ + u_int8_t full_mac[this->hmac_prf->get_block_size(this->hmac_prf)]; + + this->hmac_prf->get_bytes(this->hmac_prf,data,full_mac); + + if (signature.len != BLOCK_SIZE) + { + return FALSE; + } + + /* compare mac aka signature :-) */ + if (memcmp(signature.ptr,full_mac,BLOCK_SIZE) == 0) + { + return TRUE; + } + else + { + return FALSE; + } +} + +/** + * Implementation of signer_t.get_key_size. + */ +static size_t get_key_size (private_hmac_signer_t *this) +{ + /* for HMAC signer, IKEv2 uses block size as key size */ + return this->hmac_prf->get_block_size(this->hmac_prf); +} + +/** + * Implementation of signer_t.get_block_size. + */ +static size_t get_block_size (private_hmac_signer_t *this) +{ + return BLOCK_SIZE; +} + +/** + * Implementation of signer_t.set_key. + */ +static void set_key (private_hmac_signer_t *this, chunk_t key) +{ + this->hmac_prf->set_key(this->hmac_prf,key); +} + +/** + * Implementation of signer_t.destroy. + */ +static status_t destroy(private_hmac_signer_t *this) +{ + this->hmac_prf->destroy(this->hmac_prf); + allocator_free(this); + return SUCCESS; +} + +/* + * Described in header + */ +hmac_signer_t *hmac_signer_create(hash_algorithm_t hash_algoritm) +{ + private_hmac_signer_t *this = allocator_alloc_thing(private_hmac_signer_t); + + this->hmac_prf = (prf_t *) hmac_prf_create(hash_algoritm); + + if (this->hmac_prf == NULL) + { + /* algorithm not supported */ + allocator_free(this); + return NULL; + } + + /* interface functions */ + this->public.signer_interface.get_signature = (void (*) (signer_t*, chunk_t, u_int8_t*))get_signature; + this->public.signer_interface.allocate_signature = (void (*) (signer_t*, chunk_t, chunk_t*))allocate_signature; + this->public.signer_interface.verify_signature = (bool (*) (signer_t*, chunk_t, chunk_t))verify_signature; + this->public.signer_interface.get_key_size = (size_t (*) (signer_t*))get_key_size; + this->public.signer_interface.get_block_size = (size_t (*) (signer_t*))get_block_size; + this->public.signer_interface.set_key = (void (*) (signer_t*,chunk_t))set_key; + this->public.signer_interface.destroy = (void (*) (signer_t*))destroy; + + return &(this->public); +} -- cgit v1.2.3