/* * Copyright (C) 2006-2012 Tobias Brunner * Copyright (C) 2006 Daniel Roethlisberger * Copyright (C) 2005-2006 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. */ /** * @defgroup kernel_ipsec kernel_ipsec * @{ @ingroup hkernel */ #ifndef KERNEL_IPSEC_H_ #define KERNEL_IPSEC_H_ typedef struct kernel_ipsec_t kernel_ipsec_t; #include #include #include #include #include /** * Interface to the ipsec subsystem of the kernel. * * The kernel ipsec interface handles the communication with the kernel * for SA and policy management. It allows setup of these, and provides * further the handling of kernel events. * Policy information are cached in the interface. This is necessary to do * reference counting. The Linux kernel does not allow the same policy * installed twice, but we need this as CHILD_SA exist multiple times * when rekeying. Thats why we do reference counting of policies. */ struct kernel_ipsec_t { /** * Get the feature set supported by this kernel backend. * * @return ORed feature-set of backend */ kernel_feature_t (*get_features)(kernel_ipsec_t *this); /** * Get a SPI from the kernel. * * @param src source address of SA * @param dst destination address of SA * @param protocol protocol for SA (ESP/AH) * @param reqid unique ID for this SA * @param spi allocated spi * @return SUCCESS if operation completed */ status_t (*get_spi)(kernel_ipsec_t *this, host_t *src, host_t *dst, u_int8_t protocol, u_int32_t reqid, u_int32_t *spi); /** * Get a Compression Parameter Index (CPI) from the kernel. * * @param src source address of SA * @param dst destination address of SA * @param reqid unique ID for the corresponding SA * @param cpi allocated cpi * @return SUCCESS if operation completed */ status_t (*get_cpi)(kernel_ipsec_t *this, host_t *src, host_t *dst, u_int32_t reqid, u_int16_t *cpi); /** * Add an SA to the SAD. * * add_sa() may update an already allocated * SPI (via get_spi). In this case, the replace * flag must be set. * This function does install a single SA for a * single protocol in one direction. * * @param src source address for this SA * @param dst destination address for this SA * @param spi SPI allocated by us or remote peer * @param protocol protocol for this SA (ESP/AH) * @param reqid unique ID for this SA * @param mark mark for this SA * @param tfc Traffic Flow Confidentiality padding for this SA * @param lifetime lifetime_cfg_t for this SA * @param enc_alg Algorithm to use for encryption (ESP only) * @param enc_key key to use for encryption * @param int_alg Algorithm to use for integrity protection * @param int_key key to use for integrity protection * @param mode mode of the SA (tunnel, transport) * @param ipcomp IPComp transform to use * @param cpi CPI for IPComp * @param replay_window anti-replay window size * @param initiator TRUE if initiator of the exchange creating this SA * @param encap enable UDP encapsulation for NAT traversal * @param esn TRUE to use Extended Sequence Numbers * @param inbound TRUE if this is an inbound SA * @param src_ts traffic selector with BEET source address * @param dst_ts traffic selector with BEET destination address * @return SUCCESS if operation completed */ status_t (*add_sa) (kernel_ipsec_t *this, host_t *src, host_t *dst, u_int32_t spi, u_int8_t protocol, u_int32_t reqid, mark_t mark, u_int32_t tfc, lifetime_cfg_t *lifetime, u_int16_t enc_alg, chunk_t enc_key, u_int16_t int_alg, chunk_t int_key, ipsec_mode_t mode, u_int16_t ipcomp, u_int16_t cpi, u_int32_t replay_window, bool initiator, bool encap, bool esn, bool inbound, traffic_selector_t *src_ts, traffic_selector_t *dst_ts); /** * Update the hosts on an installed SA. * * We cannot directly update the destination address as the kernel * requires the spi, the protocol AND the destination address (and family) * to identify SAs. Therefore if the destination address changed we * create a new SA and delete the old one. * * @param spi SPI of the SA * @param protocol protocol for this SA (ESP/AH) * @param cpi CPI for IPComp, 0 if no IPComp is used * @param src current source address * @param dst current destination address * @param new_src new source address * @param new_dst new destination address * @param encap current use of UDP encapsulation * @param new_encap new use of UDP encapsulation * @param mark optional mark for this SA * @return SUCCESS if operation completed, NOT_SUPPORTED if * the kernel interface can't update the SA */ status_t (*update_sa)(kernel_ipsec_t *this, u_int32_t spi, u_int8_t protocol, u_int16_t cpi, host_t *src, host_t *dst, host_t *new_src, host_t *new_dst, bool encap, bool new_encap, mark_t mark); /** * Query the number of bytes processed by an SA from the SAD. * * @param src source address for this SA * @param dst destination address for this SA * @param spi SPI allocated by us or remote peer * @param protocol protocol for this SA (ESP/AH) * @param mark optional mark for this SA * @param[out] bytes the number of bytes processed by SA * @param[out] packets number of packets processed by SA * @param[out] time last (monotonic) time of SA use * @return SUCCESS if operation completed */ status_t (*query_sa) (kernel_ipsec_t *this, host_t *src, host_t *dst, u_int32_t spi, u_int8_t protocol, mark_t mark, u_int64_t *bytes, u_int64_t *packets, time_t *time); /** * Delete a previusly installed SA from the SAD. * * @param src source address for this SA * @param dst destination address for this SA * @param spi SPI allocated by us or remote peer * @param protocol protocol for this SA (ESP/AH) * @param cpi CPI for IPComp or 0 * @param mark optional mark for this SA * @return SUCCESS if operation completed */ status_t (*del_sa) (kernel_ipsec_t *this, host_t *src, host_t *dst, u_int32_t spi, u_int8_t protocol, u_int16_t cpi, mark_t mark); /** * Flush all SAs from the SAD. * * @return SUCCESS if operation completed */ status_t (*flush_sas) (kernel_ipsec_t *this); /** * Add a policy to the SPD. * * A policy is always associated to an SA. Traffic which matches a * policy is handled by the SA with the same reqid. * * @param src source address of SA * @param dst dest address of SA * @param src_ts traffic selector to match traffic source * @param dst_ts traffic selector to match traffic dest * @param direction direction of traffic, POLICY_(IN|OUT|FWD) * @param type type of policy, POLICY_(IPSEC|PASS|DROP) * @param sa details about the SA(s) tied to this policy * @param mark mark for this policy * @param priority priority of this policy * @return SUCCESS if operation completed */ status_t (*add_policy) (kernel_ipsec_t *this, host_t *src, host_t *dst, traffic_selector_t *src_ts, traffic_selector_t *dst_ts, policy_dir_t direction, policy_type_t type, ipsec_sa_cfg_t *sa, mark_t mark, policy_priority_t priority); /** * Query the use time of a policy. * * The use time of a policy is the time the policy was used for the last * time. It is not the system time, but a monotonic timestamp as returned * by time_monotonic. * * @param src_ts traffic selector to match traffic source * @param dst_ts traffic selector to match traffic dest * @param direction direction of traffic, POLICY_(IN|OUT|FWD) * @param mark optional mark * @param[out] use_time the monotonic timestamp of this SA's last use * @return SUCCESS if operation completed */ status_t (*query_policy) (kernel_ipsec_t *this, traffic_selector_t *src_ts, traffic_selector_t *dst_ts, policy_dir_t direction, mark_t mark, time_t *use_time); /** * Remove a policy from the SPD. * * The kernel interface implements reference counting for policies. * If the same policy is installed multiple times (in the case of rekeying), * the reference counter is increased. del_policy() decreases the ref counter * and removes the policy only when no more references are available. * * @param src_ts traffic selector to match traffic source * @param dst_ts traffic selector to match traffic dest * @param direction direction of traffic, POLICY_(IN|OUT|FWD) * @param reqid unique ID of the associated SA * @param mark optional mark * @param priority priority of the policy * @return SUCCESS if operation completed */ status_t (*del_policy) (kernel_ipsec_t *this, traffic_selector_t *src_ts, traffic_selector_t *dst_ts, policy_dir_t direction, u_int32_t reqid, mark_t mark, policy_priority_t priority); /** * Flush all policies from the SPD. * * @return SUCCESS if operation completed */ status_t (*flush_policies) (kernel_ipsec_t *this); /** * Install a bypass policy for the given socket. * * @param fd socket file descriptor to setup policy for * @param family protocol family of the socket * @return TRUE of policy set up successfully */ bool (*bypass_socket)(kernel_ipsec_t *this, int fd, int family); /** * Enable decapsulation of ESP-in-UDP packets for the given port/socket. * * @param fd socket file descriptor * @param family protocol family of the socket * @param port the UDP port * @return TRUE if UDP decapsulation was enabled successfully */ bool (*enable_udp_decap)(kernel_ipsec_t *this, int fd, int family, u_int16_t port); /** * Destroy the implementation. */ void (*destroy) (kernel_ipsec_t *this); }; /** * Helper function to (un-)register IPsec kernel interfaces from plugin features. * * This function is a plugin_feature_callback_t and can be used with the * PLUGIN_CALLBACK macro to register an IPsec kernel interface constructor. * * @param plugin plugin registering the kernel interface * @param feature associated plugin feature * @param reg TRUE to register, FALSE to unregister * @param data data passed to callback, an kernel_ipsec_constructor_t */ bool kernel_ipsec_register(plugin_t *plugin, plugin_feature_t *feature, bool reg, void *data); #endif /** KERNEL_IPSEC_H_ @}*/