eap-radius: support plain XAuth RADIUS authentication using User-Password

src/libcharon/plugins/eap_radius/Makefile.am

@@ -17,6 +17,7 @@ endif
 libstrongswan_eap_radius_la_SOURCES = \
 	eap_radius_plugin.h eap_radius_plugin.c \
 	eap_radius.h eap_radius.c \
+	eap_radius_xauth.h eap_radius_xauth.c \
 	eap_radius_accounting.h eap_radius_accounting.c \
 	eap_radius_provider.h eap_radius_provider.c \
 	eap_radius_dae.h eap_radius_dae.c \

src/libcharon/plugins/eap_radius/eap_radius_plugin.c

@@ -17,6 +17,7 @@
 #include "eap_radius_plugin.h"
 
 #include "eap_radius.h"
+#include "eap_radius_xauth.h"
 #include "eap_radius_accounting.h"
 #include "eap_radius_dae.h"
 #include "eap_radius_forward.h"
@@ -236,6 +237,9 @@ METHOD(plugin_t, get_features, int,
 		PLUGIN_CALLBACK(eap_method_register, eap_radius_create),
 			PLUGIN_PROVIDE(EAP_SERVER, EAP_RADIUS),
 				PLUGIN_DEPENDS(CUSTOM, "eap-radius"),
+		PLUGIN_CALLBACK(xauth_method_register, eap_radius_xauth_create_server),
+			PLUGIN_PROVIDE(XAUTH_SERVER, "radius"),
+				PLUGIN_DEPENDS(CUSTOM, "eap-radius"),
 		PLUGIN_CALLBACK((plugin_feature_callback_t)plugin_cb, NULL),
 			PLUGIN_PROVIDE(CUSTOM, "eap-radius"),
 				PLUGIN_DEPENDS(HASHER, HASH_MD5),

src/libcharon/plugins/eap_radius/eap_radius_xauth.c

@@ -0,0 +1,199 @@
+/*
+ * Copyright (C) 2013 Martin Willi
+ * Copyright (C) 2013 revosec AG
+ *
+ * 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_radius_xauth.h"
+#include "eap_radius_plugin.h"
+#include "eap_radius.h"
+
+#include <daemon.h>
+#include <radius_client.h>
+
+
+typedef struct private_eap_radius_xauth_t private_eap_radius_xauth_t;
+
+/**
+ * Private data of an eap_radius_xauth_t object.
+ */
+struct private_eap_radius_xauth_t {
+
+	/**
+	 * Public interface.
+	 */
+	eap_radius_xauth_t public;
+
+	/**
+	 * ID of the server
+	 */
+	identification_t *server;
+
+	/**
+	 * ID of the peer
+	 */
+	identification_t *peer;
+
+	/**
+	 * RADIUS connection
+	 */
+	radius_client_t *client;
+};
+
+METHOD(xauth_method_t, initiate, status_t,
+	private_eap_radius_xauth_t *this, cp_payload_t **out)
+{
+	cp_payload_t *cp;
+
+	cp = cp_payload_create_type(CONFIGURATION_V1, CFG_REQUEST);
+	cp->add_attribute(cp, configuration_attribute_create_chunk(
+				CONFIGURATION_ATTRIBUTE_V1, XAUTH_USER_NAME, chunk_empty));
+	cp->add_attribute(cp, configuration_attribute_create_chunk(
+				CONFIGURATION_ATTRIBUTE_V1, XAUTH_USER_PASSWORD, chunk_empty));
+	*out = cp;
+	return NEED_MORE;
+}
+
+/**
+ * Verify a password using RADIUS User-Name/User-Password attributes
+ */
+static status_t verify_radius(private_eap_radius_xauth_t *this, chunk_t pass)
+{
+	radius_message_t *request, *response;
+	status_t status = FAILED;
+
+	request = radius_message_create(RMC_ACCESS_REQUEST);
+	request->add(request, RAT_USER_NAME, this->peer->get_encoding(this->peer));
+	request->add(request, RAT_USER_PASSWORD, pass);
+
+	eap_radius_build_attributes(request);
+
+	response = this->client->request(this->client, request);
+	if (response)
+	{
+		switch (response->get_code(response))
+		{
+			case RMC_ACCESS_ACCEPT:
+				eap_radius_process_attributes(response);
+				status = SUCCESS;
+				break;
+			case RMC_ACCESS_CHALLENGE:
+				DBG1(DBG_IKE, "RADIUS Access-Challenge not supported");
+				/* FALL */
+			case RMC_ACCESS_REJECT:
+			default:
+				DBG1(DBG_IKE, "RADIUS authentication of '%Y' failed",
+					 this->peer);
+				break;
+		}
+		response->destroy(response);
+	}
+	else
+	{
+		eap_radius_handle_timeout(NULL);
+	}
+	request->destroy(request);
+	return status;
+}
+
+METHOD(xauth_method_t, process, status_t,
+	private_eap_radius_xauth_t *this, cp_payload_t *in, cp_payload_t **out)
+{
+	configuration_attribute_t *attr;
+	enumerator_t *enumerator;
+	identification_t *id;
+	chunk_t user = chunk_empty, pass = chunk_empty;
+
+	enumerator = in->create_attribute_enumerator(in);
+	while (enumerator->enumerate(enumerator, &attr))
+	{
+		switch (attr->get_type(attr))
+		{
+			case XAUTH_USER_NAME:
+				user = attr->get_chunk(attr);
+				break;
+			case XAUTH_USER_PASSWORD:
+				pass = attr->get_chunk(attr);
+				/* trim password to any null termination. As User-Password
+				 * uses null padding, we can't have any null in it, and some
+				 * clients actually send null terminated strings (Android). */
+				pass.len = strnlen(pass.ptr, pass.len);
+				break;
+			default:
+				break;
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	if (!user.ptr || !pass.ptr)
+	{
+		DBG1(DBG_IKE, "peer did not respond to our XAuth request");
+		return FAILED;
+	}
+	if (user.len)
+	{
+		id = identification_create_from_data(user);
+		if (!id)
+		{
+			DBG1(DBG_IKE, "failed to parse provided XAuth username");
+			return FAILED;
+		}
+		this->peer->destroy(this->peer);
+		this->peer = id;
+	}
+	return verify_radius(this, pass);
+}
+
+METHOD(xauth_method_t, get_identity, identification_t*,
+	private_eap_radius_xauth_t *this)
+{
+	return this->peer;
+}
+
+METHOD(xauth_method_t, destroy, void,
+	private_eap_radius_xauth_t *this)
+{
+	DESTROY_IF(this->client);
+	this->server->destroy(this->server);
+	this->peer->destroy(this->peer);
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+eap_radius_xauth_t *eap_radius_xauth_create_server(identification_t *server,
+												   identification_t *peer)
+{
+	private_eap_radius_xauth_t *this;
+
+	INIT(this,
+		.public = {
+			.xauth_method = {
+				.initiate = _initiate,
+				.process = _process,
+				.get_identity = _get_identity,
+				.destroy = _destroy,
+			},
+		},
+		.server = server->clone(server),
+		.peer = peer->clone(peer),
+		.client = eap_radius_create_client(),
+	);
+
+	if (!this->client)
+	{
+		destroy(this);
+		return NULL;
+	}
+	return &this->public;
+}

src/libcharon/plugins/eap_radius/eap_radius_xauth.h

@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2013 Martin Willi
+ * Copyright (C) 2013 revosec AG
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup eap_radius_xauth eap_radius_xauth
+ * @{ @ingroup eap_radius
+ */
+
+#ifndef EAP_RADIUS_XAUTH_H_
+#define EAP_RADIUS_XAUTH_H_
+
+#include <sa/xauth/xauth_method.h>
+
+typedef struct eap_radius_xauth_t eap_radius_xauth_t;
+
+/**
+ * XAuth backend using plain RADIUS authentication (no EAP involved).
+ */
+struct eap_radius_xauth_t {
+
+	/**
+	 * Implements XAuth module interface
+	 */
+	xauth_method_t xauth_method;
+};
+
+/**
+ * Creates the RADIUS XAuth method, acting as server.
+ *
+ * @param server	ID of the XAuth server
+ * @param peer		ID of the XAuth client
+ * @return			xauth_generic_t object
+ */
+eap_radius_xauth_t *eap_radius_xauth_create_server(identification_t *server,
+												   identification_t *peer);
+
+#endif /** EAP_RADIUS_XAUTH_H_ @}*/