diff options
Diffstat (limited to 'src/charon/sa/authenticators/rsa_authenticator.c')
| -rw-r--r-- | src/charon/sa/authenticators/rsa_authenticator.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/src/charon/sa/authenticators/rsa_authenticator.c b/src/charon/sa/authenticators/rsa_authenticator.c new file mode 100644 index 000000000..8632c2314 --- /dev/null +++ b/src/charon/sa/authenticators/rsa_authenticator.c @@ -0,0 +1,194 @@ +/** + * @file authenticator.c + * + * @brief Implementation of authenticator_t. + * + */ + +/* + * Copyright (C) 2005-2006 Martin Willi + * Copyright (C) 2005 Jan Hutter + * 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 <http://www.fsf.org/copyleft/gpl.txt>. + * + * 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 <string.h> + +#include "rsa_authenticator.h" + +#include <config/policies/policy.h> +#include <daemon.h> + + +typedef struct private_rsa_authenticator_t private_rsa_authenticator_t; + +/** + * Private data of an rsa_authenticator_t object. + */ +struct private_rsa_authenticator_t { + + /** + * Public authenticator_t interface. + */ + rsa_authenticator_t public; + + /** + * Assigned IKE_SA + */ + ike_sa_t *ike_sa; +}; + +/** + * Builds the octets to be signed as described in section 2.15 of RFC 4306 + */ +chunk_t build_tbs_octets(private_rsa_authenticator_t *this, chunk_t ike_sa_init, + chunk_t nonce, identification_t *id, prf_t *prf) +{ + u_int8_t id_header_buf[] = {0x00, 0x00, 0x00, 0x00}; + chunk_t id_header = chunk_from_buf(id_header_buf); + chunk_t id_with_header, id_prfd, id_encoding; + + id_header_buf[0] = id->get_type(id); + id_encoding = id->get_encoding(id); + + id_with_header = chunk_cat("cc", id_header, id_encoding); + prf->allocate_bytes(prf, id_with_header, &id_prfd); + chunk_free(&id_with_header); + + return chunk_cat("ccm", ike_sa_init, nonce, id_prfd); +} + +/** + * Implementation of authenticator_t.verify. + */ +static status_t verify(private_rsa_authenticator_t *this, chunk_t ike_sa_init, + chunk_t my_nonce, auth_payload_t *auth_payload) +{ + status_t status; + chunk_t auth_data, octets; + rsa_public_key_t *public_key; + identification_t *other_id; + + other_id = this->ike_sa->get_other_id(this->ike_sa); + + if (auth_payload->get_auth_method(auth_payload) != AUTH_RSA) + { + return INVALID_ARG; + } + auth_data = auth_payload->get_data(auth_payload); + public_key = charon->credentials->get_trusted_public_key(charon->credentials, + other_id); + if (public_key == NULL) + { + DBG1(DBG_IKE, "no RSA public key found for '%D'", other_id); + return NOT_FOUND; + } + octets = build_tbs_octets(this, ike_sa_init, my_nonce, other_id, + this->ike_sa->get_auth_verify(this->ike_sa)); + status = public_key->verify_emsa_pkcs1_signature(public_key, octets, auth_data); + chunk_free(&octets); + + if (status != SUCCESS) + { + DBG1(DBG_IKE, "RSA signature verification failed"); + return status; + } + + DBG1(DBG_IKE, "authentication of '%D' with %N successful", + other_id, auth_method_names, AUTH_RSA); + return SUCCESS; +} + +/** + * Implementation of authenticator_t.build. + */ +static status_t build(private_rsa_authenticator_t *this, chunk_t ike_sa_init, + chunk_t other_nonce, auth_payload_t **auth_payload) +{ + chunk_t chunk; + chunk_t octets; + chunk_t auth_data; + status_t status; + rsa_public_key_t *my_pubkey; + rsa_private_key_t *my_key; + identification_t *my_id; + + my_id = this->ike_sa->get_my_id(this->ike_sa); + DBG1(DBG_IKE, "authentication of '%D' with %N (myself)", + my_id, auth_method_names, AUTH_RSA); + DBG2(DBG_IKE, "looking for RSA public key belonging to '%D'", my_id); + + my_pubkey = charon->credentials->get_rsa_public_key(charon->credentials, my_id); + if (my_pubkey == NULL) + { + DBG1(DBG_IKE, "no RSA public key found for '%D'", my_id); + return NOT_FOUND; + } + DBG2(DBG_IKE, "matching RSA public key found"); + chunk = my_pubkey->get_keyid(my_pubkey); + DBG2(DBG_IKE, "looking for RSA private key with keyid %#B", &chunk); + my_key = charon->credentials->get_rsa_private_key(charon->credentials, my_pubkey); + if (my_key == NULL) + { + DBG1(DBG_IKE, "no RSA private key found with for %D with keyid %#B", + my_id, &chunk); + return NOT_FOUND; + } + DBG2(DBG_IKE, "matching RSA private key found"); + + octets = build_tbs_octets(this, ike_sa_init, other_nonce, my_id, + this->ike_sa->get_auth_build(this->ike_sa)); + status = my_key->build_emsa_pkcs1_signature(my_key, HASH_SHA1, octets, &auth_data); + chunk_free(&octets); + + if (status != SUCCESS) + { + my_key->destroy(my_key); + DBG1(DBG_IKE, "build signature of SHA1 hash failed"); + return status; + } + DBG2(DBG_IKE, "successfully signed with RSA private key"); + + *auth_payload = auth_payload_create(); + (*auth_payload)->set_auth_method(*auth_payload, AUTH_RSA); + (*auth_payload)->set_data(*auth_payload, auth_data); + + my_key->destroy(my_key); + chunk_free(&auth_data); + return SUCCESS; +} + +/** + * Implementation of authenticator_t.destroy. + */ +static void destroy(private_rsa_authenticator_t *this) +{ + free(this); +} + +/* + * Described in header. + */ +rsa_authenticator_t *rsa_authenticator_create(ike_sa_t *ike_sa) +{ + private_rsa_authenticator_t *this = malloc_thing(private_rsa_authenticator_t); + + /* public functions */ + this->public.authenticator_interface.verify = (status_t(*)(authenticator_t*,chunk_t,chunk_t,auth_payload_t*))verify; + this->public.authenticator_interface.build = (status_t(*)(authenticator_t*,chunk_t,chunk_t,auth_payload_t**))build; + this->public.authenticator_interface.destroy = (void(*)(authenticator_t*))destroy; + + /* private data */ + this->ike_sa = ike_sa; + + return &this->public; +} |