diff options
Diffstat (limited to 'src/charon/plugins/eap_aka/eap_aka_peer.c')
| -rw-r--r-- | src/charon/plugins/eap_aka/eap_aka_peer.c | 397 |
1 files changed, 397 insertions, 0 deletions
diff --git a/src/charon/plugins/eap_aka/eap_aka_peer.c b/src/charon/plugins/eap_aka/eap_aka_peer.c new file mode 100644 index 000000000..079ab13a6 --- /dev/null +++ b/src/charon/plugins/eap_aka/eap_aka_peer.c @@ -0,0 +1,397 @@ +/* + * Copyright (C) 2006-2009 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 "eap_aka_peer.h" + +#include <library.h> +#include <daemon.h> + +#include <simaka_message.h> +#include <simaka_crypto.h> + +typedef struct private_eap_aka_peer_t private_eap_aka_peer_t; + +/** + * Private data of an eap_aka_peer_t object. + */ +struct private_eap_aka_peer_t { + + /** + * Public authenticator_t interface. + */ + eap_aka_peer_t public; + + /** + * EAP-AKA crypto helper + */ + simaka_crypto_t *crypto; + + /** + * ID of the peer + */ + identification_t *peer; + + /** + * MSK + */ + chunk_t msk; +}; + +/** + * Create a AKA_CLIENT_ERROR: "Unable to process" + */ +static eap_payload_t* create_client_error(private_eap_aka_peer_t *this, + u_int8_t identifier) +{ + simaka_message_t *message; + eap_payload_t *out; + u_int16_t encoded; + + DBG1(DBG_IKE, "sending client error '%N'", + simaka_client_error_names, AKA_UNABLE_TO_PROCESS); + + message = simaka_message_create(FALSE, identifier, + EAP_AKA, AKA_CLIENT_ERROR); + encoded = htons(AKA_UNABLE_TO_PROCESS); + message->add_attribute(message, AT_CLIENT_ERROR_CODE, + chunk_create((char*)&encoded, sizeof(encoded))); + out = message->generate(message, this->crypto, chunk_empty); + message->destroy(message); + return out; +} + +/** + * Process an EAP-AKA/Request/Challenge message + */ +static status_t process_challenge(private_eap_aka_peer_t *this, + simaka_message_t *in, eap_payload_t **out) +{ + simaka_message_t *message; + enumerator_t *enumerator; + simaka_attribute_t type; + sim_card_t *card; + chunk_t data, rand = chunk_empty, autn = chunk_empty; + u_char res[AKA_RES_LEN], ck[AKA_CK_LEN], ik[AKA_IK_LEN], auts[AKA_AUTS_LEN]; + status_t status = NOT_FOUND; + + enumerator = in->create_attribute_enumerator(in); + while (enumerator->enumerate(enumerator, &type, &data)) + { + switch (type) + { + case AT_RAND: + rand = data; + break; + case AT_AUTN: + autn = data; + break; + default: + if (!simaka_attribute_skippable(type)) + { + *out = create_client_error(this, in->get_identifier(in)); + enumerator->destroy(enumerator); + return NEED_MORE; + } + break; + } + } + enumerator->destroy(enumerator); + + if (!rand.len || !autn.len) + { + DBG1(DBG_IKE, "received invalid EAP-AKA challenge message"); + *out = create_client_error(this, in->get_identifier(in)); + return NEED_MORE; + } + + enumerator = charon->sim->create_card_enumerator(charon->sim); + while (enumerator->enumerate(enumerator, &card)) + { + status = card->get_quintuplet(card, this->peer, rand.ptr, autn.ptr, + ck, ik, res); + if (status != FAILED) + { /* try next on error */ + break; + } + } + enumerator->destroy(enumerator); + + if (status == INVALID_STATE && + card->resync(card, this->peer, rand.ptr, auts)) + { + DBG1(DBG_IKE, "received SQN invalid, sending %N", + simaka_subtype_names, AKA_SYNCHRONIZATION_FAILURE); + message = simaka_message_create(FALSE, in->get_identifier(in), + EAP_AKA, AKA_SYNCHRONIZATION_FAILURE); + message->add_attribute(message, AT_AUTS, + chunk_create(auts, AKA_AUTS_LEN)); + *out = message->generate(message, this->crypto, chunk_empty); + message->destroy(message); + return NEED_MORE; + } + if (status != SUCCESS) + { + DBG1(DBG_IKE, "no USIM found with quintuplets for '%Y', sending %N", + this->peer, simaka_subtype_names, AKA_AUTHENTICATION_REJECT); + message = simaka_message_create(FALSE, in->get_identifier(in), + EAP_AKA, AKA_AUTHENTICATION_REJECT); + *out = message->generate(message, this->crypto, chunk_empty); + message->destroy(message); + return NEED_MORE; + } + + data = chunk_cata("cc", chunk_create(ik, AKA_IK_LEN), + chunk_create(ck, AKA_CK_LEN)); + free(this->msk.ptr); + this->msk = this->crypto->derive_keys_full(this->crypto, this->peer, data); + + /* verify EAP message MAC AT_MAC */ + if (!in->verify(in, this->crypto, chunk_empty)) + { + DBG1(DBG_IKE, "AT_MAC verification failed "); + *out = create_client_error(this, in->get_identifier(in)); + return NEED_MORE; + } + + message = simaka_message_create(FALSE, in->get_identifier(in), + EAP_AKA, AKA_CHALLENGE); + message->add_attribute(message, AT_RES, chunk_create(res, AKA_RES_LEN)); + *out = message->generate(message, this->crypto, chunk_empty); + message->destroy(message); + return NEED_MORE; +} + +/** + * Process an EAP-AKA/Request/Identity message + */ +static status_t process_identity(private_eap_aka_peer_t *this, + simaka_message_t *in, eap_payload_t **out) +{ + simaka_message_t *message; + enumerator_t *enumerator; + simaka_attribute_t type; + chunk_t data; + + enumerator = in->create_attribute_enumerator(in); + while (enumerator->enumerate(enumerator, &type, &data)) + { + switch (type) + { + case AT_PERMANENT_ID_REQ: + case AT_FULLAUTH_ID_REQ: + case AT_ANY_ID_REQ: + DBG1(DBG_IKE, "server requested %N, sending '%Y'", + simaka_attribute_names, type, this->peer); + /* we reply with our permanent identity in any case */ + break; + default: + if (!simaka_attribute_skippable(type)) + { + *out = create_client_error(this, in->get_identifier(in)); + enumerator->destroy(enumerator); + return NEED_MORE; + } + break; + } + } + enumerator->destroy(enumerator); + + message = simaka_message_create(FALSE, in->get_identifier(in), + EAP_AKA, AKA_IDENTITY); + message->add_attribute(message, AT_IDENTITY, + this->peer->get_encoding(this->peer)); + *out = message->generate(message, this->crypto, chunk_empty); + message->destroy(message); + return NEED_MORE; +} + +/** + * Process an EAP-AKA/Request/Notification message + */ +static status_t process_notification(private_eap_aka_peer_t *this, + simaka_message_t *in, eap_payload_t **out) +{ + simaka_message_t *message; + enumerator_t *enumerator; + simaka_attribute_t type; + chunk_t data; + bool success = TRUE; + + enumerator = in->create_attribute_enumerator(in); + while (enumerator->enumerate(enumerator, &type, &data)) + { + if (type == AT_NOTIFICATION) + { + u_int16_t code; + + memcpy(&code, data.ptr, sizeof(code)); + code = ntohs(code); + + /* test success bit */ + if (!(data.ptr[0] & 0x80)) + { + success = FALSE; + DBG1(DBG_IKE, "received EAP-AKA notification error '%N'", + simaka_notification_names, code); + } + else + { + DBG1(DBG_IKE, "received EAP-AKA notification '%N'", + simaka_notification_names, code); + } + } + else if (!simaka_attribute_skippable(type)) + { + success = FALSE; + break; + } + } + enumerator->destroy(enumerator); + + if (success) + { /* empty notification reply */ + message = simaka_message_create(FALSE, in->get_identifier(in), + EAP_AKA, AKA_NOTIFICATION); + *out = message->generate(message, this->crypto, chunk_empty); + message->destroy(message); + } + else + { + *out = create_client_error(this, in->get_identifier(in)); + } + return NEED_MORE; +} + + +/** + * Implementation of eap_method_t.process + */ +static status_t process(private_eap_aka_peer_t *this, + eap_payload_t *in, eap_payload_t **out) +{ + simaka_message_t *message; + status_t status; + + message = simaka_message_create_from_payload(in); + if (!message) + { + *out = create_client_error(this, in->get_identifier(in)); + return NEED_MORE; + } + if (!message->parse(message, this->crypto)) + { + message->destroy(message); + *out = create_client_error(this, in->get_identifier(in)); + return NEED_MORE; + } + switch (message->get_subtype(message)) + { + case AKA_IDENTITY: + status = process_identity(this, message, out); + break; + case AKA_CHALLENGE: + status = process_challenge(this, message, out); + break; + case AKA_NOTIFICATION: + status = process_notification(this, message, out); + break; + default: + DBG1(DBG_IKE, "unable to process EAP-AKA subtype %N", + simaka_subtype_names, message->get_subtype(message)); + *out = create_client_error(this, in->get_identifier(in)); + status = NEED_MORE; + break; + } + message->destroy(message); + return status; +} + +/** + * Implementation of eap_method_t.initiate + */ +static status_t initiate(private_eap_aka_peer_t *this, eap_payload_t **out) +{ + /* peer never initiates */ + return FAILED; +} + +/** + * Implementation of eap_method_t.get_type. + */ +static eap_type_t get_type(private_eap_aka_peer_t *this, u_int32_t *vendor) +{ + *vendor = 0; + return EAP_AKA; +} + +/** + * Implementation of eap_method_t.get_msk. + */ +static status_t get_msk(private_eap_aka_peer_t *this, chunk_t *msk) +{ + if (this->msk.ptr) + { + *msk = this->msk; + return SUCCESS; + } + return FAILED; +} + +/** + * Implementation of eap_method_t.is_mutual. + */ +static bool is_mutual(private_eap_aka_peer_t *this) +{ + return TRUE; +} + +/** + * Implementation of eap_method_t.destroy. + */ +static void destroy(private_eap_aka_peer_t *this) +{ + this->crypto->destroy(this->crypto); + this->peer->destroy(this->peer); + free(this->msk.ptr); + free(this); +} + +/* + * Described in header. + */ +eap_aka_peer_t *eap_aka_peer_create(identification_t *server, + identification_t *peer) +{ + private_eap_aka_peer_t *this = malloc_thing(private_eap_aka_peer_t); + + this->public.interface.initiate = (status_t(*)(eap_method_t*,eap_payload_t**))initiate; + this->public.interface.process = (status_t(*)(eap_method_t*,eap_payload_t*,eap_payload_t**))process; + this->public.interface.get_type = (eap_type_t(*)(eap_method_t*,u_int32_t*))get_type; + this->public.interface.is_mutual = (bool(*)(eap_method_t*))is_mutual; + this->public.interface.get_msk = (status_t(*)(eap_method_t*,chunk_t*))get_msk; + this->public.interface.destroy = (void(*)(eap_method_t*))destroy; + + this->crypto = simaka_crypto_create(); + if (!this->crypto) + { + free(this); + return NULL; + } + this->peer = peer->clone(peer); + this->msk = chunk_empty; + + return &this->public; +} + |