Add a DNS attribute handler to updown, passing servers to updown script

2012-08-21 09:38:01 +02:00
parent c60f1da424
commit e0d3014a17
6 changed files with 377 additions and 4 deletions
@@ -0,0 +1,243 @@
+/*
+ * Copyright (C) 2012 Martin Willi
+ * Copyright (C) 2012 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 "updown_handler.h"
+
+#include <daemon.h>
+#include <utils/linked_list.h>
+#include <threading/rwlock.h>
+
+typedef struct private_updown_handler_t private_updown_handler_t;
+
+/**
+ * Private data of an updown_handler_t object.
+ */
+struct private_updown_handler_t {
+
+	/**
+	 * Public updown_handler_t interface.
+	 */
+	updown_handler_t public;
+
+	/**
+	 * List of connection specific attributes, as attributes_t
+	 */
+	linked_list_t *attrs;
+
+	/**
+	 * rwlock to lock access to pools
+	 */
+	rwlock_t *lock;
+};
+
+/**
+ * Attributes assigned to an IKE_SA
+ */
+typedef struct {
+	/** unique IKE_SA identifier */
+	u_int id;
+	/** list of DNS attributes, as host_t */
+	linked_list_t *dns;
+} attributes_t;
+
+/**
+ * Destroy an attributes_t entry
+ */
+static void attributes_destroy(attributes_t *this)
+{
+	this->dns->destroy_offset(this->dns, offsetof(host_t, destroy));
+	free(this);
+}
+
+METHOD(attribute_handler_t, handle, bool,
+	private_updown_handler_t *this, identification_t *server,
+	configuration_attribute_type_t type, chunk_t data)
+{
+	attributes_t *current, *attr = NULL;
+	enumerator_t *enumerator;
+	ike_sa_t *ike_sa;
+	host_t *host;
+
+	ike_sa = charon->bus->get_sa(charon->bus);
+	if (!ike_sa)
+	{
+		return FALSE;
+	}
+	switch (type)
+	{
+		case INTERNAL_IP4_DNS:
+			host = host_create_from_chunk(AF_INET, data, 0);
+			break;
+		case INTERNAL_IP6_DNS:
+			host = host_create_from_chunk(AF_INET6, data, 0);
+			break;
+		default:
+			return FALSE;
+	}
+	if (!host)
+	{
+		return FALSE;
+	}
+
+	this->lock->write_lock(this->lock);
+	enumerator = this->attrs->create_enumerator(this->attrs);
+	while (enumerator->enumerate(enumerator, &current))
+	{
+		if (current->id == ike_sa->get_unique_id(ike_sa))
+		{
+			attr = current;
+		}
+	}
+	enumerator->destroy(enumerator);
+
+	if (!attr)
+	{
+		INIT(attr,
+			.id = ike_sa->get_unique_id(ike_sa),
+			.dns = linked_list_create(),
+		);
+		this->attrs->insert_last(this->attrs, attr);
+	}
+	attr->dns->insert_last(attr->dns, host);
+	this->lock->unlock(this->lock);
+
+	return TRUE;
+}
+
+METHOD(attribute_handler_t, release, void,
+	private_updown_handler_t *this, identification_t *server,
+	configuration_attribute_type_t type, chunk_t data)
+{
+	attributes_t *attr;
+	enumerator_t *enumerator, *servers;
+	ike_sa_t *ike_sa;
+	host_t *host;
+	bool found = FALSE;
+	int family;
+
+	switch (type)
+	{
+		case INTERNAL_IP4_DNS:
+			family = AF_INET;
+			break;
+		case INTERNAL_IP6_DNS:
+			family = AF_INET6;
+			break;
+		default:
+			return;
+	}
+
+	ike_sa = charon->bus->get_sa(charon->bus);
+	if (ike_sa)
+	{
+		this->lock->write_lock(this->lock);
+		enumerator = this->attrs->create_enumerator(this->attrs);
+		while (enumerator->enumerate(enumerator, &attr))
+		{
+			if (attr->id == ike_sa->get_unique_id(ike_sa))
+			{
+				servers = attr->dns->create_enumerator(attr->dns);
+				while (servers->enumerate(servers, &host))
+				{
+					if (host->get_family(host) == family &&
+						chunk_equals(data, host->get_address(host)))
+					{
+						attr->dns->remove_at(attr->dns, servers);
+						host->destroy(host);
+						found = TRUE;
+						break;
+					}
+				}
+				servers->destroy(servers);
+				if (attr->dns->get_count(attr->dns) == 0)
+				{
+					this->attrs->remove_at(this->attrs, enumerator);
+					attributes_destroy(attr);
+					break;
+				}
+			}
+			if (found)
+			{
+				break;
+			}
+		}
+		enumerator->destroy(enumerator);
+		this->lock->unlock(this->lock);
+	}
+}
+
+METHOD(updown_handler_t, create_dns_enumerator, enumerator_t*,
+	private_updown_handler_t *this, u_int id)
+{
+	attributes_t *attr;
+	enumerator_t *enumerator;
+	ike_sa_t *ike_sa;
+
+	ike_sa = charon->bus->get_sa(charon->bus);
+	if (!ike_sa)
+	{
+		return FALSE;
+	}
+
+	this->lock->read_lock(this->lock);
+	enumerator = this->attrs->create_enumerator(this->attrs);
+	while (enumerator->enumerate(enumerator, &attr))
+	{
+		if (attr->id == ike_sa->get_unique_id(ike_sa))
+		{
+			enumerator->destroy(enumerator);
+			return enumerator_create_cleaner(
+										attr->dns->create_enumerator(attr->dns),
+										(void*)this->lock->unlock, this->lock);
+		}
+	}
+	enumerator->destroy(enumerator);
+	this->lock->unlock(this->lock);
+
+	return enumerator_create_empty();
+}
+
+
+METHOD(updown_handler_t, destroy, void,
+	private_updown_handler_t *this)
+{
+	this->lock->destroy(this->lock);
+	this->attrs->destroy_function(this->attrs, (void*)attributes_destroy);
+	free(this);
+}
+
+/**
+ * See header
+ */
+updown_handler_t *updown_handler_create()
+{
+	private_updown_handler_t *this;
+
+	INIT(this,
+		.public = {
+			.handler = {
+				.handle = _handle,
+				.release = _release,
+				.create_attribute_enumerator = enumerator_create_empty,
+			},
+			.create_dns_enumerator = _create_dns_enumerator,
+			.destroy = _destroy,
+		},
+		.attrs = linked_list_create(),
+		.lock = rwlock_create(RWLOCK_TYPE_DEFAULT),
+	);
+
+	return &this->public;
+}