strongswan/src/charon/sa/authenticators/eap_authenticator.c

361 lines
9.3 KiB
C

/**
* @file eap_authenticator.c
*
* @brief Implementation of eap_authenticator_t.
*
*/
/*
* Copyright (C) 2006 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 <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 "eap_authenticator.h"
#include <daemon.h>
#include <config/peer_cfg.h>
#include <sa/authenticators/eap/eap_method.h>
typedef struct private_eap_authenticator_t private_eap_authenticator_t;
/**
* Private data of an eap_authenticator_t object.
*/
struct private_eap_authenticator_t {
/**
* Public authenticator_t interface.
*/
eap_authenticator_t public;
/**
* Assigned IKE_SA
*/
ike_sa_t *ike_sa;
/**
* Role of this authenticator, PEER or SERVER
*/
eap_role_t role;
/**
* Current EAP method processing
*/
eap_method_t *method;
/**
* MSK used to build and verify auth payload
*/
chunk_t msk;
};
extern chunk_t build_shared_key_signature(chunk_t ike_sa_init, chunk_t nonce,
chunk_t secret, identification_t *id,
prf_t *prf_skp, prf_t *prf);
/**
* Implementation of authenticator_t.verify.
*/
static status_t verify(private_eap_authenticator_t *this, chunk_t ike_sa_init,
chunk_t my_nonce, auth_payload_t *auth_payload)
{
chunk_t auth_data, recv_auth_data;
identification_t *other_id = this->ike_sa->get_other_id(this->ike_sa);
auth_data = build_shared_key_signature(ike_sa_init, my_nonce, this->msk,
other_id, this->ike_sa->get_auth_verify(this->ike_sa),
this->ike_sa->get_prf(this->ike_sa));
recv_auth_data = auth_payload->get_data(auth_payload);
if (!chunk_equals(auth_data, recv_auth_data))
{
DBG1(DBG_IKE, "verification of AUTH payload created from EAP MSK failed");
chunk_free(&auth_data);
return FAILED;
}
chunk_free(&auth_data);
DBG1(DBG_IKE, "authentication of '%D' with %N successful",
other_id, auth_method_names, AUTH_EAP);
return SUCCESS;
}
/**
* Implementation of authenticator_t.build.
*/
static status_t build(private_eap_authenticator_t *this, chunk_t ike_sa_init,
chunk_t other_nonce, auth_payload_t **auth_payload)
{
chunk_t auth_data;
identification_t *my_id = this->ike_sa->get_my_id(this->ike_sa);
DBG1(DBG_IKE, "authentication of '%D' (myself) with %N",
my_id, auth_method_names, AUTH_EAP);
auth_data = build_shared_key_signature(ike_sa_init, other_nonce, this->msk,
my_id, this->ike_sa->get_auth_build(this->ike_sa),
this->ike_sa->get_prf(this->ike_sa));
*auth_payload = auth_payload_create();
(*auth_payload)->set_auth_method(*auth_payload, AUTH_PSK);
(*auth_payload)->set_data(*auth_payload, auth_data);
chunk_free(&auth_data);
return SUCCESS;
}
/**
* Implementation of eap_authenticator_t.initiate
*/
static status_t initiate(private_eap_authenticator_t *this, eap_type_t type,
eap_payload_t **out)
{
/* if initiate() is called, role is always server */
this->role = EAP_SERVER;
if (type == 0)
{
DBG1(DBG_IKE,
"client requested EAP authentication, but configuration forbids it");
*out = eap_payload_create_code(EAP_FAILURE);
return FAILED;
}
DBG1(DBG_IKE, "requesting %N authentication", eap_type_names, type);
this->method = eap_method_create(type, this->role,
this->ike_sa->get_my_id(this->ike_sa),
this->ike_sa->get_other_id(this->ike_sa));
if (this->method == NULL)
{
DBG1(DBG_IKE, "configured EAP server method %N not supported, sending %N",
eap_type_names, type, eap_code_names, EAP_FAILURE);
*out = eap_payload_create_code(EAP_FAILURE);
return FAILED;
}
if (this->method->initiate(this->method, out) != NEED_MORE)
{
DBG1(DBG_IKE, "failed to initiate %N, sending %N",
eap_type_names, type, eap_code_names, EAP_FAILURE);
*out = eap_payload_create_code(EAP_FAILURE);
return FAILED;
}
return NEED_MORE;
}
/**
* Processing method for a peer
*/
static status_t process_peer(private_eap_authenticator_t *this,
eap_payload_t *in, eap_payload_t **out)
{
eap_type_t type = in->get_type(in);
if (type == EAP_IDENTITY)
{
eap_method_t *method = eap_method_create(type, EAP_PEER,
this->ike_sa->get_other_id(this->ike_sa),
this->ike_sa->get_my_id(this->ike_sa));
if (method == NULL || method->process(method, in, out) != SUCCESS)
{
DBG1(DBG_IKE, "EAP server requested %N, but unable to process",
eap_type_names, type);
DESTROY_IF(method);
return FAILED;
}
DBG1(DBG_IKE, "EAP server requested %N, sending IKE identity",
eap_type_names, type);
method->destroy(method);
return NEED_MORE;
}
/* create an eap_method for the first call */
if (this->method == NULL)
{
DBG1(DBG_IKE, "EAP server requested %N authentication",
eap_type_names, type);
this->method = eap_method_create(type, EAP_PEER,
this->ike_sa->get_other_id(this->ike_sa),
this->ike_sa->get_my_id(this->ike_sa));
if (this->method == NULL)
{
DBG1(DBG_IKE, "EAP server requested unsupported "
"EAP method %N, sending EAP_NAK", eap_type_names, type);
*out = eap_payload_create_nak();
return NEED_MORE;
}
}
switch (this->method->process(this->method, in, out))
{
case NEED_MORE:
return NEED_MORE;
case SUCCESS:
DBG1(DBG_IKE, "EAP method %N succeded",
eap_type_names, this->method->get_type(this->method));
return SUCCESS;
case FAILED:
default:
DBG1(DBG_IKE, "EAP method %N failed",
eap_type_names, this->method->get_type(this->method));
return FAILED;
}
}
/**
* Processing method for a server
*/
static status_t process_server(private_eap_authenticator_t *this,
eap_payload_t *in, eap_payload_t **out)
{
switch (this->method->process(this->method, in, out))
{
case NEED_MORE:
return NEED_MORE;
case SUCCESS:
if (this->method->get_msk(this->method, &this->msk) == SUCCESS)
{
DBG1(DBG_IKE, "EAP method %N succeded, MSK established",
eap_type_names, this->method->get_type(this->method));
this->msk = chunk_clone(this->msk);
*out = eap_payload_create_code(EAP_SUCCESS);
return SUCCESS;
}
DBG1(DBG_IKE, "EAP method %N succeded, but no MSK established",
eap_type_names, this->method->get_type(this->method));
*out = eap_payload_create_code(EAP_FAILURE);
return FAILED;
case FAILED:
default:
DBG1(DBG_IKE, "EAP method %N failed for peer %D",
eap_type_names, this->method->get_type(this->method),
this->ike_sa->get_other_id(this->ike_sa));
*out = eap_payload_create_code(EAP_FAILURE);
return FAILED;
}
}
/**
* Implementation of eap_authenticator_t.process
*/
static status_t process(private_eap_authenticator_t *this, eap_payload_t *in,
eap_payload_t **out)
{
eap_code_t code = in->get_code(in);
switch (this->role)
{
case EAP_SERVER:
{
switch (code)
{
case EAP_RESPONSE:
{
return process_server(this, in, out);
}
default:
{
DBG1(DBG_IKE, "received %N, sending %N",
eap_code_names, code, eap_code_names, EAP_FAILURE);
*out = eap_payload_create_code(EAP_FAILURE);
return FAILED;
}
}
}
case EAP_PEER:
{
switch (code)
{
case EAP_REQUEST:
{
return process_peer(this, in, out);
}
case EAP_SUCCESS:
{
if (this->method->get_msk(this->method, &this->msk) == SUCCESS)
{
this->msk = chunk_clone(this->msk);
return SUCCESS;
}
DBG1(DBG_IKE, "EAP method %N has no MSK established",
eap_type_names, this->method->get_type(this->method));
return FAILED;
}
case EAP_FAILURE:
default:
{
DBG1(DBG_IKE, "received %N, EAP authentication failed",
eap_code_names, code);
return FAILED;
}
}
}
default:
{
return FAILED;
}
}
}
/**
* Implementation of authenticator_t.is_mutual.
*/
static bool is_mutual(private_eap_authenticator_t *this)
{
if (this->method)
{
return this->method->is_mutual(this->method);
}
return FALSE;
}
/**
* Implementation of authenticator_t.destroy.
*/
static void destroy(private_eap_authenticator_t *this)
{
DESTROY_IF(this->method);
chunk_free(&this->msk);
free(this);
}
/*
* Described in header.
*/
eap_authenticator_t *eap_authenticator_create(ike_sa_t *ike_sa)
{
private_eap_authenticator_t *this = malloc_thing(private_eap_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;
this->public.is_mutual = (bool(*)(eap_authenticator_t*))is_mutual;
this->public.initiate = (status_t(*)(eap_authenticator_t*,eap_type_t,eap_payload_t**))initiate;
this->public.process = (status_t(*)(eap_authenticator_t*,eap_payload_t*,eap_payload_t**))process;
/* private data */
this->ike_sa = ike_sa;
this->role = EAP_PEER;
this->method = NULL;
this->msk = chunk_empty;
return &this->public;
}