Splitted EAP-AKA in peer and server implementations, use libsimaka helper library

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;
+}
+