Merge branch 'eap-client-select'

This brings support for EAP-Nak payloads on the client (to select a
specific or supported method), and the server (via the eap-dynamic
plugin which selects a method supported/requested by the client).

src/libcharon/Makefile.am

@@ -316,6 +316,13 @@ if MONOLITHIC
 endif
 endif
 
+if USE_EAP_DYNAMIC
+  SUBDIRS += plugins/eap_dynamic
+if MONOLITHIC
+  libcharon_la_LIBADD += plugins/eap_dynamic/libstrongswan-eap-dynamic.la
+endif
+endif
+
 if USE_EAP_RADIUS
   SUBDIRS += plugins/eap_radius
 if MONOLITHIC

src/libcharon/encoding/payloads/eap_payload.c

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2005-2010 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -20,6 +21,7 @@
 
 #include <daemon.h>
 #include <eap/eap.h>
+#include <bio/bio_writer.h>
 
 typedef struct private_eap_payload_t private_eap_payload_t;
 
@@ -217,28 +219,93 @@ METHOD(eap_payload_t, get_identifier, u_int8_t,
 	return 0;
 }
 
+/**
+ * Get the current type at the given offset into this->data.
+ * @return	the new offset or 0 if failed
+ */
+static size_t extract_type(private_eap_payload_t *this, size_t offset,
+					       eap_type_t *type, u_int32_t *vendor)
+{
+	if (this->data.len > offset)
+	{
+		*vendor = 0;
+		*type = this->data.ptr[offset];
+		if (*type != EAP_EXPANDED)
+		{
+			return offset + 1;
+		}
+		if (this->data.len >= offset + 8)
+		{
+			*vendor = untoh32(this->data.ptr + offset) & 0x00FFFFFF;
+			*type = untoh32(this->data.ptr + offset + 4);
+			return offset + 8;
+		}
+	}
+	return 0;
+}
+
 METHOD(eap_payload_t, get_type, eap_type_t,
 	private_eap_payload_t *this, u_int32_t *vendor)
 {
 	eap_type_t type;
 
 	*vendor = 0;
-	if (this->data.len > 4)
+	if (extract_type(this, 4, &type, vendor))
 	{
-		type = this->data.ptr[4];
-		if (type != EAP_EXPANDED)
-		{
-			return type;
-		}
-		if (this->data.len >= 12)
-		{
-			*vendor = untoh32(this->data.ptr + 4) & 0x00FFFFFF;
-			return untoh32(this->data.ptr + 8);
-		}
+		return type;
 	}
 	return 0;
 }
 
+/**
+ * Type enumerator
+ */
+typedef struct {
+	/** public interface */
+	enumerator_t public;
+	/** payload */
+	private_eap_payload_t *payload;
+	/** current offset in the data */
+	size_t offset;
+} type_enumerator_t;
+
+METHOD(enumerator_t, enumerate_types, bool,
+	type_enumerator_t *this, eap_type_t *type, u_int32_t *vendor)
+{
+	this->offset = extract_type(this->payload, this->offset, type, vendor);
+	return this->offset;
+}
+
+METHOD(eap_payload_t, get_types, enumerator_t*,
+	private_eap_payload_t *this)
+{
+	type_enumerator_t *enumerator;
+	eap_type_t type;
+	u_int32_t vendor;
+	size_t offset;
+
+	offset = extract_type(this, 4, &type, &vendor);
+	if (offset && type == EAP_NAK)
+	{
+		INIT(enumerator,
+			.public = {
+				.enumerate = (void*)_enumerate_types,
+				.destroy = (void*)free,
+			},
+			.payload = this,
+			.offset = offset,
+		);
+		return &enumerator->public;
+	}
+	return enumerator_create_empty();
+}
+
+METHOD(eap_payload_t, is_expanded, bool,
+	private_eap_payload_t *this)
+{
+	return this->data.len > 4 ? this->data.ptr[4] == EAP_EXPANDED : FALSE;
+}
+
 METHOD2(payload_t, eap_payload_t, destroy, void,
 	private_eap_payload_t *this)
 {
@@ -270,6 +337,8 @@ eap_payload_t *eap_payload_create()
 			.get_code = _get_code,
 			.get_identifier = _get_identifier,
 			.get_type = _get_type,
+			.get_types = _get_types,
+			.is_expanded = _is_expanded,
 			.destroy = _destroy,
 		},
 		.next_payload = NO_PAYLOAD,
@@ -313,15 +382,81 @@ eap_payload_t *eap_payload_create_code(eap_code_t code, u_int8_t identifier)
 	return eap_payload_create_data(data);
 }
 
+/**
+ * Write the given type either expanded or not
+ */
+static void write_type(bio_writer_t *writer, eap_type_t type, u_int32_t vendor,
+					   bool expanded)
+{
+	if (expanded)
+	{
+		writer->write_uint8(writer, EAP_EXPANDED);
+		writer->write_uint24(writer, vendor);
+		writer->write_uint32(writer, type);
+	}
+	else
+	{
+		writer->write_uint8(writer, type);
+	}
+}
+
 /*
  * Described in header
  */
-eap_payload_t *eap_payload_create_nak(u_int8_t identifier)
+eap_payload_t *eap_payload_create_nak(u_int8_t identifier, eap_type_t type,
+									  u_int32_t vendor, bool expanded)
 {
-	chunk_t data;
+	enumerator_t *enumerator;
+	eap_type_t reg_type;
+	u_int32_t reg_vendor;
+	bio_writer_t *writer;
+	chunk_t length, data;
+	bool added_any = FALSE, found_vendor = FALSE;
+	eap_payload_t *payload;
 
-	data = chunk_from_chars(EAP_RESPONSE, identifier, 0, 0, EAP_NAK);
-	htoun16(data.ptr + 2, data.len);
-	return eap_payload_create_data(data);
+	writer = bio_writer_create(12);
+	writer->write_uint8(writer, EAP_RESPONSE);
+	writer->write_uint8(writer, identifier);
+	length = writer->skip(writer, 2);
+
+	write_type(writer, EAP_NAK, 0, expanded);
+
+	enumerator = charon->eap->create_enumerator(charon->eap, EAP_PEER);
+	while (enumerator->enumerate(enumerator, &reg_type, &reg_vendor))
+	{
+		if ((type && type != reg_type) ||
+			(type && vendor && vendor != reg_vendor))
+		{	/* the preferred type is only sent if we actually find it */
+			continue;
+		}
+		if (!reg_vendor || expanded)
+		{
+			write_type(writer, reg_type, reg_vendor, expanded);
+			added_any = TRUE;
+		}
+		else if (reg_vendor)
+		{	/* found vendor specifc method, but this is not an expanded Nak */
+			found_vendor = TRUE;
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	if (found_vendor)
+	{	/* request an expanded authentication type */
+		write_type(writer, EAP_EXPANDED, 0, expanded);
+		added_any = TRUE;
+	}
+	if (!added_any)
+	{	/* no methods added */
+		write_type(writer, 0, 0, expanded);
+	}
+
+	/* set length */
+	data = writer->get_buf(writer);
+	htoun16(length.ptr, data.len);
+
+	payload = eap_payload_create_data(data);
+	writer->destroy(writer);
+	return payload;
 }
 

src/libcharon/encoding/payloads/eap_payload.h

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2005-2006 Martin Willi
  * Copyright (C) 2005 Jan Hutter
  * Hochschule fuer Technik Rapperswil
@@ -81,6 +82,21 @@ struct eap_payload_t {
 	 */
 	eap_type_t (*get_type) (eap_payload_t *this, u_int32_t *vendor);
 
+	/**
+	 * Enumerate the EAP method types contained in an EAP-Nak (i.e. get_type()
+	 * returns EAP_NAK).
+	 *
+	 * @return			enumerator over (eap_type_t type, u_int32_t vendor)
+	 */
+	enumerator_t* (*get_types) (eap_payload_t *this);
+
+	/**
+	 * Check if the EAP method type is encoded in the Expanded Type format.
+	 *
+	 * @return			TRUE if in Expanded Type format
+	 */
+	bool (*is_expanded) (eap_payload_t *this);
+
 	/**
 	 * Destroys an eap_payload_t object.
 	 */
@@ -126,8 +142,12 @@ eap_payload_t *eap_payload_create_code(eap_code_t code, u_int8_t identifier);
  * Creates an eap_payload_t EAP_RESPONSE containing an EAP_NAK.
  *
  * @param identifier	EAP identifier to use in payload
+ * @param type			preferred auth type, 0 to send all supported types
+ * @param vendor		vendor identifier for auth type, 0 for default
+ * @param expanded		TRUE to send an expanded Nak
  * @return 				eap_payload_t object
  */
-eap_payload_t *eap_payload_create_nak(u_int8_t identifier);
+eap_payload_t *eap_payload_create_nak(u_int8_t identifier, eap_type_t type,
+									  u_int32_t vendor, bool expanded);
 
 #endif /** EAP_PAYLOAD_H_ @}*/

src/libcharon/plugins/eap_dynamic/Makefile.am

@@ -0,0 +1,16 @@
+
+INCLUDES = -I$(top_srcdir)/src/libstrongswan -I$(top_srcdir)/src/libhydra \
+	-I$(top_srcdir)/src/libcharon
+
+AM_CFLAGS = -rdynamic
+
+if MONOLITHIC
+noinst_LTLIBRARIES = libstrongswan-eap-dynamic.la
+else
+plugin_LTLIBRARIES = libstrongswan-eap-dynamic.la
+endif
+
+libstrongswan_eap_dynamic_la_SOURCES = \
+	eap_dynamic_plugin.h eap_dynamic_plugin.c eap_dynamic.h eap_dynamic.c
+
+libstrongswan_eap_dynamic_la_LDFLAGS = -module -avoid-version

src/libcharon/plugins/eap_dynamic/eap_dynamic.c

@@ -0,0 +1,393 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * 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_dynamic.h"
+
+#include <daemon.h>
+#include <library.h>
+
+typedef struct private_eap_dynamic_t private_eap_dynamic_t;
+
+/**
+ * Private data of an eap_dynamic_t object.
+ */
+struct private_eap_dynamic_t {
+
+	/**
+	 * Public authenticator_t interface.
+	 */
+	eap_dynamic_t public;
+
+	/**
+	 * ID of the server
+	 */
+	identification_t *server;
+
+	/**
+	 * ID of the peer
+	 */
+	identification_t *peer;
+
+	/**
+	 * Our supported EAP types (as eap_vendor_type_t*)
+	 */
+	linked_list_t *types;
+
+	/**
+	 * EAP types supported by peer, if any
+	 */
+	linked_list_t *other_types;
+
+	/**
+	 * Prefer types sent by peer
+	 */
+	bool prefer_peer;
+
+	/**
+	 * The proxied EAP method
+	 */
+	eap_method_t *method;
+};
+
+/**
+ * Compare two eap_vendor_type_t objects
+ */
+static bool entry_matches(eap_vendor_type_t *item, eap_vendor_type_t *other)
+{
+	return item->type == other->type && item->vendor == other->vendor;
+}
+
+/**
+ * Load the given EAP method
+ */
+static eap_method_t *load_method(private_eap_dynamic_t *this,
+								 eap_type_t type, u_int32_t vendor)
+{
+	eap_method_t *method;
+
+	method = charon->eap->create_instance(charon->eap, type, vendor, EAP_SERVER,
+										  this->server, this->peer);
+	if (!method)
+	{
+		if (vendor)
+		{
+			DBG1(DBG_IKE, "loading vendor specific EAP method %d-%d failed",
+				 type, vendor);
+		}
+		else
+		{
+			DBG1(DBG_IKE, "loading %N method failed", eap_type_names, type);
+		}
+	}
+	return method;
+}
+
+/**
+ * Select the first method we can instantiate and is supported by both peers.
+ */
+static void select_method(private_eap_dynamic_t *this)
+{
+	eap_vendor_type_t *entry;
+	linked_list_t *outer = this->types, *inner = this->other_types;
+	char *who = "peer";
+
+	if (this->other_types && this->prefer_peer)
+	{
+		outer = this->other_types;
+		inner = this->types;
+		who = "us";
+	}
+
+	while (outer->remove_first(outer, (void*)&entry) == SUCCESS)
+	{
+		if (inner)
+		{
+			if (inner->find_first(inner, (void*)entry_matches,
+								  NULL, entry) != SUCCESS)
+			{
+				if (entry->vendor)
+				{
+					DBG2(DBG_IKE, "proposed vendor specific EAP method %d-%d "
+						 "not supported by %s, skipped", entry->type,
+						  entry->vendor, who);
+				}
+				else
+				{
+					DBG2(DBG_IKE, "proposed %N method not supported by %s, "
+						 "skipped", eap_type_names, entry->type, who);
+				}
+				free(entry);
+				continue;
+			}
+		}
+		this->method = load_method(this, entry->type, entry->vendor);
+		if (this->method)
+		{
+			if (entry->vendor)
+			{
+				DBG1(DBG_IKE, "vendor specific EAP method %d-%d selected",
+					 entry->type, entry->vendor);
+			}
+			else
+			{
+				DBG1(DBG_IKE, "%N method selected", eap_type_names,
+					 entry->type);
+			}
+			free(entry);
+			break;
+		}
+		free(entry);
+	}
+}
+
+METHOD(eap_method_t, initiate, status_t,
+	private_eap_dynamic_t *this, eap_payload_t **out)
+{
+	if (!this->method)
+	{
+		select_method(this);
+		if (!this->method)
+		{
+			DBG1(DBG_IKE, "no supported EAP method found");
+			return FAILED;
+		}
+	}
+	return this->method->initiate(this->method, out);
+}
+
+METHOD(eap_method_t, process, status_t,
+	private_eap_dynamic_t *this, eap_payload_t *in, eap_payload_t **out)
+{
+	eap_type_t received_type, type;
+	u_int32_t received_vendor, vendor;
+
+	received_type = in->get_type(in, &received_vendor);
+	if (received_vendor == 0 && received_type == EAP_NAK)
+	{
+		enumerator_t *enumerator;
+
+		DBG1(DBG_IKE, "received %N, selecting a different EAP method",
+			 eap_type_names, EAP_NAK);
+
+		if (this->other_types)
+		{	/* we already received a Nak or a proper response before */
+			DBG1(DBG_IKE, "%N is not supported in this state", eap_type_names,
+				 EAP_NAK);
+			return FAILED;
+		}
+
+		this->other_types = linked_list_create();
+		enumerator = in->get_types(in);
+		while (enumerator->enumerate(enumerator, &type, &vendor))
+		{
+			eap_vendor_type_t *entry;
+
+			if (!type)
+			{
+				DBG1(DBG_IKE, "peer does not support any other EAP methods");
+				enumerator->destroy(enumerator);
+				return FAILED;
+			}
+			INIT(entry,
+				.type = type,
+				.vendor = vendor,
+			);
+			this->other_types->insert_last(this->other_types, entry);
+		}
+		enumerator->destroy(enumerator);
+
+		/* restart with a different method */
+		this->method->destroy(this->method);
+		this->method = NULL;
+		return initiate(this, out);
+	}
+	if (!this->other_types)
+	{	/* so we don't handle EAP-Naks later */
+		this->other_types = linked_list_create();
+	}
+	if (this->method)
+	{
+		return this->method->process(this->method, in, out);
+	}
+	return FAILED;
+}
+
+METHOD(eap_method_t, get_type, eap_type_t,
+	private_eap_dynamic_t *this, u_int32_t *vendor)
+{
+	if (this->method)
+	{
+		return this->method->get_type(this->method, vendor);
+	}
+	*vendor = 0;
+	return EAP_DYNAMIC;
+}
+
+METHOD(eap_method_t, get_msk, status_t,
+	private_eap_dynamic_t *this, chunk_t *msk)
+{
+	if (this->method)
+	{
+		return this->method->get_msk(this->method, msk);
+	}
+	return FAILED;
+}
+
+METHOD(eap_method_t, get_identifier, u_int8_t,
+	private_eap_dynamic_t *this)
+{
+	if (this->method)
+	{
+		return this->method->get_identifier(this->method);
+	}
+	return 0;
+}
+
+METHOD(eap_method_t, set_identifier, void,
+	private_eap_dynamic_t *this, u_int8_t identifier)
+{
+	if (this->method)
+	{
+		this->method->set_identifier(this->method, identifier);
+	}
+}
+
+METHOD(eap_method_t, is_mutual, bool,
+	private_eap_dynamic_t *this)
+{
+	if (this->method)
+	{
+		return this->method->is_mutual(this->method);
+	}
+	return FALSE;
+}
+
+METHOD(eap_method_t, destroy, void,
+	private_eap_dynamic_t *this)
+{
+	DESTROY_IF(this->method);
+	this->types->destroy_function(this->types, (void*)free);
+	DESTROY_FUNCTION_IF(this->other_types, (void*)free);
+	this->server->destroy(this->server);
+	this->peer->destroy(this->peer);
+	free(this);
+}
+
+/**
+ * Parse preferred EAP types
+ */
+static void handle_preferred_eap_types(private_eap_dynamic_t *this,
+									   char *methods)
+{
+	enumerator_t *enumerator;
+	eap_vendor_type_t *type, *entry;
+	linked_list_t *preferred;
+	char *method;
+
+	/* parse preferred EAP methods, format: type[-vendor], ... */
+	preferred = linked_list_create();
+	enumerator = enumerator_create_token(methods, ",", " ");
+	while (enumerator->enumerate(enumerator, &method))
+	{
+		type = eap_vendor_type_from_string(method);
+		if (type)
+		{
+			preferred->insert_last(preferred, type);
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	enumerator = this->types->create_enumerator(this->types);
+	while (preferred->remove_last(preferred, (void**)&type) == SUCCESS)
+	{	/* move (supported) types to the front, maintain the preferred order */
+		this->types->reset_enumerator(this->types, enumerator);
+		while (enumerator->enumerate(enumerator, &entry))
+		{
+			if (entry_matches(entry, type))
+			{
+				this->types->remove_at(this->types, enumerator);
+				this->types->insert_first(this->types, entry);
+				break;
+			}
+		}
+		free(type);
+	}
+	enumerator->destroy(enumerator);
+	preferred->destroy(preferred);
+}
+
+/**
+ * Get all supported EAP methods
+ */
+static void get_supported_eap_types(private_eap_dynamic_t *this)
+{
+	enumerator_t *enumerator;
+	eap_type_t type;
+	u_int32_t vendor;
+
+	enumerator = charon->eap->create_enumerator(charon->eap, EAP_SERVER);
+	while (enumerator->enumerate(enumerator, &type, &vendor))
+	{
+		eap_vendor_type_t *entry;
+
+		INIT(entry,
+			.type = type,
+			.vendor = vendor,
+		);
+		this->types->insert_last(this->types, entry);
+	}
+	enumerator->destroy(enumerator);
+}
+
+/*
+ * Defined in header
+ */
+eap_dynamic_t *eap_dynamic_create(identification_t *server,
+								  identification_t *peer)
+{
+	private_eap_dynamic_t *this;
+	char *preferred;
+
+	INIT(this,
+		.public = {
+			.interface = {
+				.initiate = _initiate,
+				.process = _process,
+				.get_type = _get_type,
+				.is_mutual = _is_mutual,
+				.get_msk = _get_msk,
+				.get_identifier = _get_identifier,
+				.set_identifier = _set_identifier,
+				.destroy = _destroy,
+			},
+		},
+		.peer = peer->clone(peer),
+		.server = server->clone(server),
+		.types = linked_list_create(),
+		.prefer_peer = lib->settings->get_bool(lib->settings,
+					"%s.plugins.eap-dynamic.prefer_peer", FALSE, charon->name),
+	);
+
+	/* get all supported EAP methods */
+	get_supported_eap_types(this);
+	/* move preferred methods to the front */
+	preferred = lib->settings->get_str(lib->settings,
+					"%s.plugins.eap-dynamic.preferred", NULL, charon->name);
+	if (preferred)
+	{
+		handle_preferred_eap_types(this, preferred);
+	}
+	return &this->public;
+}

src/libcharon/plugins/eap_dynamic/eap_dynamic.h

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * 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.
+ */
+
+/**
+ * @defgroup eap_dynamic_i eap_dynamic
+ * @{ @ingroup eap_dynamic
+ */
+
+#ifndef EAP_DYNAMIC_H_
+#define EAP_DYNAMIC_H_
+
+typedef struct eap_dynamic_t eap_dynamic_t;
+
+#include <sa/eap/eap_method.h>
+
+/**
+ * Implementation of the eap_method_t interface for a virtual EAP method that
+ * proxies other EAP methods and supports the selection of the actual method
+ * by the client.
+ */
+struct eap_dynamic_t {
+
+	/**
+	 * Implemented eap_method_t interface
+	 */
+	eap_method_t interface;
+};
+
+/**
+ * Create a dynamic EAP proxy serving any supported real method which is also
+ * supported (or selected) by the client.
+ *
+ * @param server	ID of the EAP server
+ * @param peer		ID of the EAP client
+ * @return			eap_dynamic_t object
+ */
+eap_dynamic_t *eap_dynamic_create(identification_t *server,
+								  identification_t *peer);
+
+#endif /** EAP_DYNAMIC_H_ @}*/

src/libcharon/plugins/eap_dynamic/eap_dynamic_plugin.c

@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * 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_dynamic_plugin.h"
+
+#include "eap_dynamic.h"
+
+#include <daemon.h>
+
+METHOD(plugin_t, get_name, char*,
+	eap_dynamic_plugin_t *this)
+{
+	return "eap-dynamic";
+}
+
+METHOD(plugin_t, get_features, int,
+	eap_dynamic_plugin_t *this, plugin_feature_t *features[])
+{
+	static plugin_feature_t f[] = {
+		PLUGIN_CALLBACK(eap_method_register, eap_dynamic_create),
+			PLUGIN_PROVIDE(EAP_SERVER, EAP_DYNAMIC),
+	};
+	*features = f;
+	return countof(f);
+}
+
+METHOD(plugin_t, destroy, void,
+	eap_dynamic_plugin_t *this)
+{
+	free(this);
+}
+
+/*
+ * see header file
+ */
+plugin_t *eap_dynamic_plugin_create()
+{
+	eap_dynamic_plugin_t *this;
+
+	INIT(this,
+		.plugin = {
+			.get_name = _get_name,
+			.get_features = _get_features,
+			.destroy = _destroy,
+		},
+	);
+
+	return &this->plugin;
+}
+

src/libcharon/plugins/eap_dynamic/eap_dynamic_plugin.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * 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.
+ */
+
+/**
+ * @defgroup eap_dynamic eap_dynamic
+ * @ingroup cplugins
+ *
+ * @defgroup eap_dynamic_plugin eap_dynamic_plugin
+ * @{ @ingroup eap_dynamic
+ */
+
+#ifndef EAP_DYNAMIC_PLUGIN_H_
+#define EAP_DYNAMIC_PLUGIN_H_
+
+#include <plugins/plugin.h>
+
+typedef struct eap_dynamic_plugin_t eap_dynamic_plugin_t;
+
+/**
+ * EAP plugin that can use any supported EAP method the client supports or
+ * prefers to use.
+ */
+struct eap_dynamic_plugin_t {
+
+	/**
+	 * implements plugin interface
+	 */
+	plugin_t plugin;
+};
+
+#endif /** EAP_DYNAMIC_PLUGIN_H_ @}*/

src/libcharon/plugins/eap_peap/eap_peap_peer.c

@@ -85,7 +85,7 @@ METHOD(tls_application_t, process, status_t,
 		default:
 			return FAILED;
 	}
- 		
+
 	in = eap_payload_create_data(data);
 	DBG3(DBG_IKE, "%B", &data);
 	chunk_free(&data);
@@ -151,7 +151,8 @@ METHOD(tls_application_t, process, status_t,
 		if (!this->ph2_method)
 		{
 			DBG1(DBG_IKE, "EAP method not supported");
-			this->out = eap_payload_create_nak(in->get_identifier(in));
+			this->out = eap_payload_create_nak(in->get_identifier(in), 0, 0,
+											   in->is_expanded(in));
 			in->destroy(in);
 			return NEED_MORE;
 		}

src/libcharon/plugins/eap_ttls/eap_ttls_peer.c

@@ -138,7 +138,7 @@ METHOD(tls_application_t, process, status_t,
 		chunk_free(&avp_data);
 	}
 	while (eap_pos < eap_data.len);
- 		
+
 	in = eap_payload_create_data(eap_data);
 	chunk_free(&eap_data);
 	payload = (payload_t*)in;
@@ -192,7 +192,8 @@ METHOD(tls_application_t, process, status_t,
 		if (!this->method)
 		{
 			DBG1(DBG_IKE, "EAP method not supported");
-			this->out = eap_payload_create_nak(in->get_identifier(in));
+			this->out = eap_payload_create_nak(in->get_identifier(in), 0, 0,
+											   in->is_expanded(in));
 			in->destroy(in);
 			return NEED_MORE;
 		}

src/libcharon/plugins/stroke/stroke_config.c

@@ -563,51 +563,20 @@ static auth_cfg_t *build_auth_cfg(private_stroke_config_t *this,
 	}
 	else if (strneq(auth, "eap", 3))
 	{
-		enumerator_t *enumerator;
-		char *str;
-		int i = 0, type = 0, vendor;
+		eap_vendor_type_t *type;
 
 		cfg->add(cfg, AUTH_RULE_AUTH_CLASS, AUTH_CLASS_EAP);
 
-		/* parse EAP string, format: eap[-type[-vendor]] */
-		enumerator = enumerator_create_token(auth, "-", " ");
-		while (enumerator->enumerate(enumerator, &str))
+		type = eap_vendor_type_from_string(auth);
+		if (type)
 		{
-			switch (i)
+			cfg->add(cfg, AUTH_RULE_EAP_TYPE, type->type);
+			if (type->vendor)
 			{
-				case 1:
-					type = eap_type_from_string(str);
-					if (!type)
-					{
-						type = atoi(str);
-						if (!type)
-						{
-							DBG1(DBG_CFG, "unknown EAP method: %s", str);
-							break;
-						}
-					}
-					cfg->add(cfg, AUTH_RULE_EAP_TYPE, type);
-					break;
-				case 2:
-					if (type)
-					{
-						vendor = atoi(str);
-						if (vendor)
-						{
-							cfg->add(cfg, AUTH_RULE_EAP_VENDOR, vendor);
-						}
-						else
-						{
-							DBG1(DBG_CFG, "unknown EAP vendor: %s", str);
-						}
-					}
-					break;
-				default:
-					break;
+				cfg->add(cfg, AUTH_RULE_EAP_VENDOR, type->vendor);
 			}
-			i++;
+			free(type);
 		}
-		enumerator->destroy(enumerator);
 
 		if (msg->add_conn.eap_identity)
 		{

src/libcharon/sa/eap/eap_manager.c

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2008 Martin Willi
  * Hochschule fuer Technik Rapperswil
  *
@@ -104,6 +105,44 @@ METHOD(eap_manager_t, remove_method, void,
 	this->lock->unlock(this->lock);
 }
 
+/**
+ * filter the registered methods
+ */
+static bool filter_methods(uintptr_t role, eap_entry_t **entry,
+						   eap_type_t *type, void *in, u_int32_t *vendor)
+{
+	if ((*entry)->role != (eap_role_t)role)
+	{
+		return FALSE;
+	}
+	if ((*entry)->vendor == 0 &&
+	   ((*entry)->type < 4 || (*entry)->type == EAP_EXPANDED ||
+	    (*entry)->type > EAP_EXPERIMENTAL))
+	{	/* filter invalid types */
+		return FALSE;
+	}
+	if (type)
+	{
+		*type = (*entry)->type;
+	}
+	if (vendor)
+	{
+		*vendor = (*entry)->vendor;
+	}
+	return TRUE;
+}
+
+METHOD(eap_manager_t, create_enumerator, enumerator_t*,
+	private_eap_manager_t *this, eap_role_t role)
+{
+	this->lock->read_lock(this->lock);
+	return enumerator_create_cleaner(
+				enumerator_create_filter(
+					this->methods->create_enumerator(this->methods),
+					(void*)filter_methods, (void*)(uintptr_t)role, NULL),
+				(void*)this->lock->unlock, this->lock);
+}
+
 METHOD(eap_manager_t, create_instance, eap_method_t*,
 	private_eap_manager_t *this, eap_type_t type, u_int32_t vendor,
 	eap_role_t role, identification_t *server, identification_t *peer)
@@ -150,6 +189,7 @@ eap_manager_t *eap_manager_create()
 			.public = {
 				.add_method = _add_method,
 				.remove_method = _remove_method,
+				.create_enumerator = _create_enumerator,
 				.create_instance = _create_instance,
 				.destroy = _destroy,
 			},

src/libcharon/sa/eap/eap_manager.h

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2008 Martin Willi
  * Hochschule fuer Technik Rapperswil
  *
@@ -53,6 +54,17 @@ struct eap_manager_t {
 	 */
 	void (*remove_method)(eap_manager_t *this, eap_constructor_t constructor);
 
+	/**
+	 * Enumerate the registered EAP authentication methods for the given role.
+	 *
+	 * @note Only authentication types are enumerated (e.g. EAP-Identity is not
+	 * even though it is registered as method with this manager).
+	 *
+	 * @param role			EAP role of methods to enumerate
+	 * @return				enumerator over (eap_type_t type, u_int32_t vendor)
+	 */
+	enumerator_t* (*create_enumerator)(eap_manager_t *this, eap_role_t role);
+
 	/**
 	 * Create a new EAP method instance.
 	 *

src/libcharon/sa/ikev2/authenticators/eap_authenticator.c

@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2012 Tobias Brunner
  * Copyright (C) 2006-2009 Martin Willi
  * Hochschule fuer Technik Rapperswil
  *
@@ -186,9 +187,9 @@ static eap_payload_t* server_initiate_eap(private_eap_authenticator_t *this,
 	if (this->method)
 	{
 		action = "initiating";
-		type = this->method->get_type(this->method, &vendor);
 		if (this->method->initiate(this->method, &out) == NEED_MORE)
 		{
+			type = this->method->get_type(this->method, &vendor);
 			if (vendor)
 			{
 				DBG1(DBG_IKE, "initiating EAP vendor type %d-%d method (id 0x%02X)",
@@ -201,6 +202,8 @@ static eap_payload_t* server_initiate_eap(private_eap_authenticator_t *this,
 			}
 			return out;
 		}
+		/* type might have changed for virtual methods */
+		type = this->method->get_type(this->method, &vendor);
 	}
 	if (vendor)
 	{
@@ -233,9 +236,10 @@ static void replace_eap_identity(private_eap_authenticator_t *this)
 static eap_payload_t* server_process_eap(private_eap_authenticator_t *this,
 										 eap_payload_t *in)
 {
-	eap_type_t type, received_type;
-	u_int32_t vendor, received_vendor;
+	eap_type_t type, received_type, conf_type;
+	u_int32_t vendor, received_vendor, conf_vendor;
 	eap_payload_t *out;
+	auth_cfg_t *auth;
 
 	if (in->get_code(in) != EAP_RESPONSE)
 	{
@@ -250,15 +254,25 @@ static eap_payload_t* server_process_eap(private_eap_authenticator_t *this,
 	{
 		if (received_vendor == 0 && received_type == EAP_NAK)
 		{
-			DBG1(DBG_IKE, "received %N, sending %N",
-				 eap_type_names, EAP_NAK, eap_code_names, EAP_FAILURE);
+			auth = this->ike_sa->get_auth_cfg(this->ike_sa, FALSE);
+			conf_type = (uintptr_t)auth->get(auth, AUTH_RULE_EAP_TYPE);
+			conf_vendor = (uintptr_t)auth->get(auth, AUTH_RULE_EAP_VENDOR);
+			if ((type == EAP_IDENTITY && !vendor) ||
+				(type == conf_type && vendor == conf_vendor))
+			{
+				DBG1(DBG_IKE, "received %N, sending %N",
+					 eap_type_names, EAP_NAK, eap_code_names, EAP_FAILURE);
+				return eap_payload_create_code(EAP_FAILURE,
+											   in->get_identifier(in));
+			}
+			/* virtual methods handle NAKs in process() */
 		}
 		else
 		{
 			DBG1(DBG_IKE, "received invalid EAP response, sending %N",
 				 eap_code_names, EAP_FAILURE);
+			return eap_payload_create_code(EAP_FAILURE, in->get_identifier(in));
 		}
-		return eap_payload_create_code(EAP_FAILURE, in->get_identifier(in));
 	}
 
 	switch (this->method->process(this->method, in, &out))
@@ -302,6 +316,8 @@ static eap_payload_t* server_process_eap(private_eap_authenticator_t *this,
 			return eap_payload_create_code(EAP_SUCCESS, in->get_identifier(in));
 		case FAILED:
 		default:
+			/* type might have changed for virtual methods */
+			type = this->method->get_type(this->method, &vendor);
 			if (vendor)
 			{
 				DBG1(DBG_IKE, "EAP vendor specific method %d-%d failed for "
@@ -324,8 +340,8 @@ static eap_payload_t* server_process_eap(private_eap_authenticator_t *this,
 static eap_payload_t* client_process_eap(private_eap_authenticator_t *this,
 										 eap_payload_t *in)
 {
-	eap_type_t type;
-	u_int32_t vendor;
+	eap_type_t type, conf_type;
+	u_int32_t vendor, conf_vendor;
 	auth_cfg_t *auth;
 	eap_payload_t *out;
 	identification_t *id;
@@ -357,9 +373,11 @@ static eap_payload_t* client_process_eap(private_eap_authenticator_t *this,
 			this->method->destroy(this->method);
 			this->method = NULL;
 		}
+		/* FIXME: sending a Nak is not correct here as EAP_IDENTITY (1) is no
+		 * EAP method (types 3-253, 255) */
 		DBG1(DBG_IKE, "%N not supported, sending EAP_NAK",
 			 eap_type_names, type);
-		return eap_payload_create_nak(in->get_identifier(in));
+		return eap_payload_create_nak(in->get_identifier(in), 0, 0, FALSE);
 	}
 	if (this->method == NULL)
 	{
@@ -373,11 +391,31 @@ static eap_payload_t* client_process_eap(private_eap_authenticator_t *this,
 			DBG1(DBG_IKE, "server requested %N authentication (id 0x%02X)",
 				 eap_type_names, type, in->get_identifier(in));
 		}
+		auth = this->ike_sa->get_auth_cfg(this->ike_sa, TRUE);
+		conf_type = (uintptr_t)auth->get(auth, AUTH_RULE_EAP_TYPE);
+		conf_vendor = (uintptr_t)auth->get(auth, AUTH_RULE_EAP_VENDOR);
+		if (conf_type != EAP_NAK &&
+		   (conf_type != type || conf_vendor != vendor))
+		{
+			if (conf_vendor)
+			{
+				DBG1(DBG_IKE, "requesting EAP method %d-%d, sending EAP_NAK",
+					 conf_type, conf_vendor);
+			}
+			else
+			{
+				DBG1(DBG_IKE, "requesting %N authentication, sending EAP_NAK",
+					 eap_type_names, conf_type);
+			}
+			return eap_payload_create_nak(in->get_identifier(in), conf_type,
+										  conf_vendor, in->is_expanded(in));
+		}
 		this->method = load_method(this, type, vendor, EAP_PEER);
 		if (!this->method)
 		{
 			DBG1(DBG_IKE, "EAP method not supported, sending EAP_NAK");
-			return eap_payload_create_nak(in->get_identifier(in));
+			return eap_payload_create_nak(in->get_identifier(in), 0, 0,
+										  in->is_expanded(in));
 		}
 	}