1 files changed, 444 insertions, 0 deletions
diff --git a/src/libcharon/config/backend_manager.c b/src/libcharon/config/backend_manager.c
new file mode 100644
index 000000000..90ef58563
--- /dev/null
+++ b/src/libcharon/config/backend_manager.c
@@ -0,0 +1,444 @@
+/*
+ * Copyright (C) 2007-2009 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 "backend_manager.h"
+
+#include <sys/types.h>
+
+#include <daemon.h>
+#include <utils/linked_list.h>
+#include <threading/rwlock.h>
+
+
+typedef struct private_backend_manager_t private_backend_manager_t;
+
+/**
+ * Private data of an backend_manager_t object.
+ */
+struct private_backend_manager_t {
+
+	/**
+	 * Public part of backend_manager_t object.
+	 */
+	backend_manager_t public;
+
+	/**
+	 * list of registered backends
+	 */
+	linked_list_t *backends;
+
+	/**
+	 * rwlock for backends
+	 */
+	rwlock_t *lock;
+};
+
+/**
+ * match of an ike_cfg
+ */
+typedef enum ike_cfg_match_t {
+	MATCH_NONE  = 0x00,
+	MATCH_ANY   = 0x01,
+	MATCH_ME	= 0x04,
+	MATCH_OTHER = 0x08,
+} ike_cfg_match_t;
+
+/**
+ * data to pass nested IKE enumerator
+ */
+typedef struct {
+	private_backend_manager_t *this;
+	host_t *me;
+	host_t *other;
+} ike_data_t;
+
+/**
+ * inner enumerator constructor for IKE cfgs
+ */
+static enumerator_t *ike_enum_create(backend_t *backend, ike_data_t *data)
+{
+	return backend->create_ike_cfg_enumerator(backend, data->me, data->other);
+}
+
+/**
+ * get a match of a candidate ike_cfg for two hosts
+ */
+static ike_cfg_match_t get_ike_match(ike_cfg_t *cand, host_t *me, host_t *other)
+{
+	host_t *me_cand, *other_cand;
+	ike_cfg_match_t match = MATCH_NONE;
+
+	if (me)
+	{
+		me_cand = host_create_from_dns(cand->get_my_addr(cand),
+									   me->get_family(me), 0);
+		if (!me_cand)
+		{
+			return MATCH_NONE;
+		}
+		if (me_cand->ip_equals(me_cand, me))
+		{
+			match += MATCH_ME;
+		}
+		else if (me_cand->is_anyaddr(me_cand))
+		{
+			match += MATCH_ANY;
+		}
+		me_cand->destroy(me_cand);
+	}
+	else
+	{
+		match += MATCH_ANY;
+	}
+
+	if (other)
+	{
+		other_cand = host_create_from_dns(cand->get_other_addr(cand),
+										  other->get_family(other), 0);
+		if (!other_cand)
+		{
+			return MATCH_NONE;
+		}
+		if (other_cand->ip_equals(other_cand, other))
+		{
+			match += MATCH_OTHER;
+		}
+		else if (other_cand->is_anyaddr(other_cand))
+		{
+			match += MATCH_ANY;
+		}
+		other_cand->destroy(other_cand);
+	}
+	else
+	{
+		match += MATCH_ANY;
+	}
+	return match;
+}
+
+/**
+ * implements backend_manager_t.get_ike_cfg.
+ */
+static ike_cfg_t *get_ike_cfg(private_backend_manager_t *this,
+							  host_t *me, host_t *other)
+{
+	ike_cfg_t *current, *found = NULL;
+	enumerator_t *enumerator;
+	ike_cfg_match_t match, best = MATCH_ANY;
+	ike_data_t *data;
+
+	data = malloc_thing(ike_data_t);
+	data->this = this;
+	data->me = me;
+	data->other = other;
+
+	DBG2(DBG_CFG, "looking for an ike config for %H...%H", me, other);
+
+	this->lock->read_lock(this->lock);
+	enumerator = enumerator_create_nested(
+						this->backends->create_enumerator(this->backends),
+						(void*)ike_enum_create, data, (void*)free);
+	while (enumerator->enumerate(enumerator, (void**)&current))
+	{
+		match = get_ike_match(current, me, other);
+
+		if (match)
+		{
+			DBG2(DBG_CFG, "  candidate: %s...%s, prio %d",
+				 current->get_my_addr(current),
+				 current->get_other_addr(current), match);
+			if (match > best)
+			{
+				DESTROY_IF(found);
+				found = current;
+				found->get_ref(found);
+				best = match;
+			}
+		}
+	}
+	enumerator->destroy(enumerator);
+	this->lock->unlock(this->lock);
+	if (found)
+	{
+		DBG2(DBG_CFG, "found matching ike config: %s...%s with prio %d",
+			 found->get_my_addr(found), found->get_other_addr(found), best);
+	}
+	return found;
+}
+
+/**
+ * Get the best ID match in one of the configs auth_cfg
+ */
+static id_match_t get_peer_match(identification_t *id,
+								 peer_cfg_t *cfg, bool local)
+{
+	enumerator_t *enumerator;
+	auth_cfg_t *auth;
+	identification_t *candidate;
+	id_match_t match = ID_MATCH_NONE;
+
+	if (!id)
+	{
+		return ID_MATCH_ANY;
+	}
+
+	/* compare first auth config only */
+	enumerator = cfg->create_auth_cfg_enumerator(cfg, local);
+	if (enumerator->enumerate(enumerator, &auth))
+	{
+		candidate = auth->get(auth, AUTH_RULE_IDENTITY);
+		if (candidate)
+		{
+			match = id->matches(id, candidate);
+			/* match vice-versa, as the proposed IDr might be ANY */
+			if (!match)
+			{
+				match = candidate->matches(candidate, id);
+			}
+		}
+		else
+		{
+			match = ID_MATCH_ANY;
+		}
+	}
+	enumerator->destroy(enumerator);
+	return match;
+}
+
+/**
+ * data to pass nested peer enumerator
+ */
+typedef struct {
+	rwlock_t *lock;
+	identification_t *me;
+	identification_t *other;
+} peer_data_t;
+
+/**
+ * list element to help sorting
+ */
+typedef struct {
+	id_match_t match_peer;
+	ike_cfg_match_t match_ike;
+	peer_cfg_t *cfg;
+} match_entry_t;
+
+/**
+ * inner enumerator constructor for peer cfgs
+ */
+static enumerator_t *peer_enum_create(backend_t *backend, peer_data_t *data)
+{
+	return backend->create_peer_cfg_enumerator(backend, data->me, data->other);
+}
+
+/**
+ * unlock/cleanup peer enumerator
+ */
+static void peer_enum_destroy(peer_data_t *data)
+{
+	data->lock->unlock(data->lock);
+	free(data);
+}
+
+/**
+ * convert enumerator value from match_entry to config
+ */
+static bool peer_enum_filter(linked_list_t *configs,
+							 match_entry_t **in, peer_cfg_t **out)
+{
+	*out = (*in)->cfg;
+	return TRUE;
+}
+
+/**
+ * Clean up temporary config list
+ */
+static void peer_enum_filter_destroy(linked_list_t *configs)
+{
+	match_entry_t *entry;
+
+	while (configs->remove_last(configs, (void**)&entry) == SUCCESS)
+	{
+		entry->cfg->destroy(entry->cfg);
+		free(entry);
+	}
+	configs->destroy(configs);
+}
+
+/**
+ * Insert entry into match-sorted list, using helper
+ */
+static void insert_sorted(match_entry_t *entry, linked_list_t *list,
+						  linked_list_t *helper)
+{
+	match_entry_t *current;
+
+	while (list->remove_first(list, (void**)&current) == SUCCESS)
+	{
+		helper->insert_last(helper, current);
+	}
+	while (helper->remove_first(helper, (void**)&current) == SUCCESS)
+	{
+		if (entry && (
+			 (entry->match_ike > current->match_ike &&
+			  entry->match_peer >= current->match_peer) ||
+			 (entry->match_ike >= current->match_ike &&
+			  entry->match_peer > current->match_peer)))
+		{
+			list->insert_last(list, entry);
+			entry = NULL;
+		}
+		list->insert_last(list, current);
+	}
+	if (entry)
+	{
+		list->insert_last(list, entry);
+	}
+}
+
+/**
+ * Implements backend_manager_t.create_peer_cfg_enumerator.
+ */
+static enumerator_t *create_peer_cfg_enumerator(private_backend_manager_t *this,
+							host_t *me, host_t *other, identification_t *my_id,
+							identification_t *other_id)
+{
+	enumerator_t *enumerator;
+	peer_data_t *data;
+	peer_cfg_t *cfg;
+	linked_list_t *configs, *helper;
+
+	data = malloc_thing(peer_data_t);
+	data->lock = this->lock;
+	data->me = my_id;
+	data->other = other_id;
+
+	/* create a sorted list with all matches */
+	this->lock->read_lock(this->lock);
+	enumerator = enumerator_create_nested(
+					this->backends->create_enumerator(this->backends),
+					(void*)peer_enum_create, data, (void*)peer_enum_destroy);
+
+	if (!me && !other && !my_id && !other_id)
+	{	/* shortcut if we are doing a "listall" */
+		return enumerator;
+	}
+
+	DBG1(DBG_CFG, "looking for peer configs matching %H[%Y]...%H[%Y]",
+		 me, my_id, other, other_id);
+
+	configs = linked_list_create();
+	/* only once allocated helper list for sorting */
+	helper = linked_list_create();
+	while (enumerator->enumerate(enumerator, &cfg))
+	{
+		id_match_t match_peer_me, match_peer_other;
+		ike_cfg_match_t match_ike;
+		match_entry_t *entry;
+
+		match_peer_me = get_peer_match(my_id, cfg, TRUE);
+		match_peer_other = get_peer_match(other_id, cfg, FALSE);
+		match_ike = get_ike_match(cfg->get_ike_cfg(cfg), me, other);
+
+		if (match_peer_me && match_peer_other && match_ike)
+		{
+			DBG2(DBG_CFG, "  candidate \"%s\", match: %d/%d/%d (me/other/ike)",
+				 cfg->get_name(cfg), match_peer_me, match_peer_other, match_ike);
+
+			entry = malloc_thing(match_entry_t);
+			entry->match_peer = match_peer_me + match_peer_other;
+			entry->match_ike = match_ike;
+			entry->cfg = cfg->get_ref(cfg);
+			insert_sorted(entry, configs, helper);
+		}
+	}
+	enumerator->destroy(enumerator);
+	helper->destroy(helper);
+
+	return enumerator_create_filter(configs->create_enumerator(configs),
+									(void*)peer_enum_filter, configs,
+									(void*)peer_enum_filter_destroy);
+}
+
+/**
+ * implements backend_manager_t.get_peer_cfg_by_name.
+ */
+static peer_cfg_t *get_peer_cfg_by_name(private_backend_manager_t *this, char *name)
+{
+	backend_t *backend;
+	peer_cfg_t *config = NULL;
+	enumerator_t *enumerator;
+
+	this->lock->read_lock(this->lock);
+	enumerator = this->backends->create_enumerator(this->backends);
+	while (config == NULL && enumerator->enumerate(enumerator, (void**)&backend))
+	{
+		config = backend->get_peer_cfg_by_name(backend, name);
+	}
+	enumerator->destroy(enumerator);
+	this->lock->unlock(this->lock);
+	return config;
+}
+
+/**
+ * Implementation of backend_manager_t.remove_backend.
+ */
+static void remove_backend(private_backend_manager_t *this, backend_t *backend)
+{
+	this->lock->write_lock(this->lock);
+	this->backends->remove(this->backends, backend, NULL);
+	this->lock->unlock(this->lock);
+}
+
+/**
+ * Implementation of backend_manager_t.add_backend.
+ */
+static void add_backend(private_backend_manager_t *this, backend_t *backend)
+{
+	this->lock->write_lock(this->lock);
+	this->backends->insert_last(this->backends, backend);
+	this->lock->unlock(this->lock);
+}
+
+/**
+ * Implementation of backend_manager_t.destroy.
+ */
+static void destroy(private_backend_manager_t *this)
+{
+	this->backends->destroy(this->backends);
+	this->lock->destroy(this->lock);
+	free(this);
+}
+
+/*
+ * Described in header-file
+ */
+backend_manager_t *backend_manager_create()
+{
+	private_backend_manager_t *this = malloc_thing(private_backend_manager_t);
+
+	this->public.get_ike_cfg = (ike_cfg_t* (*)(backend_manager_t*, host_t*, host_t*))get_ike_cfg;
+	this->public.get_peer_cfg_by_name = (peer_cfg_t* (*)(backend_manager_t*,char*))get_peer_cfg_by_name;
+	this->public.create_peer_cfg_enumerator = (enumerator_t* (*)(backend_manager_t*,host_t*,host_t*,identification_t*,identification_t*))create_peer_cfg_enumerator;
+	this->public.add_backend = (void(*)(backend_manager_t*, backend_t *backend))add_backend;
+	this->public.remove_backend = (void(*)(backend_manager_t*, backend_t *backend))remove_backend;
+	this->public.destroy = (void (*)(backend_manager_t*))destroy;
+
+	this->backends = linked_list_create();
+	this->lock = rwlock_create(RWLOCK_TYPE_DEFAULT);
+
+	return &this->public;
+}
+