/* * Copyright (C) 2008 Tobias Brunner * Copyright (C) 2005-2008 Martin Willi * Copyright (C) 2005 Jan Hutter * 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 . * * 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. * * $Id: ike_sa_manager.h 4811 2008-12-17 09:00:22Z martin $ */ /** * @defgroup ike_sa_manager ike_sa_manager * @{ @ingroup sa */ #ifndef IKE_SA_MANAGER_H_ #define IKE_SA_MANAGER_H_ typedef struct ike_sa_manager_t ike_sa_manager_t; #include #include #include #include /** * Manages and synchronizes access to all IKE_SAs. * * To synchronize access to thread-unsave IKE_SAs, they are checked out for * use and checked in afterwards. A checked out SA is exclusively accessible * by the owning thread. */ struct ike_sa_manager_t { /** * Checkout an existing IKE_SA. * * @param ike_sa_id the SA identifier, will be updated * @returns * - checked out IKE_SA if found * - NULL, if specified IKE_SA is not found. */ ike_sa_t* (*checkout) (ike_sa_manager_t* this, ike_sa_id_t *sa_id); /** * Create and check out a new IKE_SA. * * @param initiator TRUE for initiator, FALSE otherwise * @returns created and checked out IKE_SA */ ike_sa_t* (*checkout_new) (ike_sa_manager_t* this, bool initiator); /** * Checkout an IKE_SA by a message. * * In some situations, it is necessary that the manager knows the * message to use for the checkout. This has the following reasons: * * 1. If the targeted IKE_SA is already processing a message, we do not * check it out if the message ID is the same. * 2. If it is an IKE_SA_INIT request, we have to check if it is a * retransmission. If so, we have to drop the message, we would * create another unneeded IKE_SA for each retransmitted packet. * * A call to checkout_by_message() returns a (maybe new created) IKE_SA. * If processing the message does not make sense (for the reasons above), * NULL is returned. * * @param ike_sa_id the SA identifier, will be updated * @returns * - checked out/created IKE_SA * - NULL to not process message further */ ike_sa_t* (*checkout_by_message) (ike_sa_manager_t* this, message_t *message); /** * Checkout an IKE_SA for initiation by a peer_config. * * To initiate, a CHILD_SA may be established within an existing IKE_SA. * This call checks for an existing IKE_SA by comparing the configuration. * If the CHILD_SA can be created in an existing IKE_SA, the matching SA * is returned. * If no IKE_SA is found, a new one is created. This is also the case when * the found IKE_SA is in the DELETING state. * * @param peer_cfg configuration used to find an existing IKE_SA * @return checked out/created IKE_SA */ ike_sa_t* (*checkout_by_config) (ike_sa_manager_t* this, peer_cfg_t *peer_cfg); /** * Check for duplicates of the given IKE_SA. * * Measures are taken according to the uniqueness policy of the IKE_SA. * The return value indicates whether duplicates have been found and if * further measures should be taken (e.g. cancelling an IKE_AUTH exchange). * check_uniqueness() must be called before the IKE_SA is complete, * deadlocks occur otherwise. * * @param ike_sa ike_sa to check * @return TRUE, if the given IKE_SA has duplicates and * should be deleted */ bool (*check_uniqueness)(ike_sa_manager_t *this, ike_sa_t *ike_sa); /** * Check out an IKE_SA a unique ID. * * Every IKE_SA and every CHILD_SA is uniquely identified by an ID. * These checkout function uses, depending * on the child parameter, the unique ID of the IKE_SA or the reqid * of one of a IKE_SAs CHILD_SA. * * @param id unique ID of the object * @param child TRUE to use CHILD, FALSE to use IKE_SA * @return * - checked out IKE_SA, if found * - NULL, if not found */ ike_sa_t* (*checkout_by_id) (ike_sa_manager_t* this, u_int32_t id, bool child); /** * Check out an IKE_SA by the policy/connection name. * * Check out the IKE_SA by the configuration name, either from the IKE- or * one of its CHILD_SAs. * * @param name name of the connection/policy * @param child TRUE to use policy name, FALSE to use conn name * @return * - checked out IKE_SA, if found * - NULL, if not found */ ike_sa_t* (*checkout_by_name) (ike_sa_manager_t* this, char *name, bool child); /** * Create an enumerator over all stored IKE_SAs. * * While enumerating an IKE_SA, it is temporarily checked out and * automatically checked in after the current enumeration step. * * @return enumerator over all IKE_SAs. */ enumerator_t *(*create_enumerator) (ike_sa_manager_t* this); /** * Checkin the SA after usage. * * If the IKE_SA is not registered in the manager, a new entry is created. * * @param ike_sa_id the SA identifier, will be updated * @param ike_sa checked out SA */ void (*checkin) (ike_sa_manager_t* this, ike_sa_t *ike_sa); /** * Destroy a checked out SA. * * The IKE SA is destroyed without notification of the remote peer. * Use this only if the other peer doesn't respond or behaves not * as predicted. * Checking in and destruction is an atomic operation (for the IKE_SA), * so this can be called if the SA is in a "unclean" state, without the * risk that another thread can get the SA. * * @param ike_sa SA to delete */ void (*checkin_and_destroy) (ike_sa_manager_t* this, ike_sa_t *ike_sa); /** * Get the number of IKE_SAs which are in the connecting state. * * To prevent the server from resource exhaustion, cookies and other * mechanisms are used. The number of half open IKE_SAs is a good * indicator to see if a peer is flooding the server. * If a host is supplied, only the number of half open IKE_SAs initiated * from this IP are counted. * Only SAs for which we are the responder are counted. * * @param ip NULL for all, IP for half open IKE_SAs with IP * @return number of half open IKE_SAs */ int (*get_half_open_count) (ike_sa_manager_t *this, host_t *ip); /** * Delete all existing IKE_SAs and destroy them immediately. * * Threads will be driven out, so all SAs can be deleted cleanly. */ void (*flush)(ike_sa_manager_t *this); /** * Destroys the manager with all associated SAs. * * A call to flush() is required before calling destroy. */ void (*destroy) (ike_sa_manager_t *this); }; /** * Create the IKE_SA manager. * * @returns ike_sa_manager_t object, NULL if initialization fails */ ike_sa_manager_t *ike_sa_manager_create(void); #endif /*IKE_SA_MANAGER_H_ @} */