src/charon/kernel/kernel_interface.h

   1 /*
   2  * Copyright (C) 2006-2008 Tobias Brunner
   3  * Copyright (C) 2006 Daniel Roethlisberger
   4  * Copyright (C) 2005-2006 Martin Willi
   5  * Copyright (C) 2005 Jan Hutter
   6  * Hochschule fuer Technik Rapperswil
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2 of the License, or (at your
  11  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  * for more details.
  17  *
  18  * $Id$
  19  */
  20
  21 /**
  22  * @defgroup kernel_interface kernel_interface
  23  * @{ @ingroup kernel
  24  */
  25
  26 #ifndef KERNEL_INTERFACE_H_
  27 #define KERNEL_INTERFACE_H_
  28
  29 typedef struct kernel_interface_t kernel_interface_t;
  30
  31 #include <utils/host.h>
  32 #include <crypto/prf_plus.h>
  33 #include <encoding/payloads/proposal_substructure.h>
  34
  35 #include <kernel/kernel_ipsec.h>
  36 #include <kernel/kernel_net.h>
  37
  38 /**
  39  * Constructor function for ipsec kernel interface
  40  */
  41 typedef kernel_ipsec_t* (*kernel_ipsec_constructor_t)(void);
  42
  43 /**
  44  * Constructor function for network kernel interface
  45  */
  46 typedef kernel_net_t* (*kernel_net_constructor_t)(void);
  47
  48 /**
  49  * Manager and wrapper for different kernel interfaces.
  50  *
  51  * The kernel interface handles the communication with the kernel
  52  * for SA and policy management and interface and IP address management.
  53  */
  54 struct kernel_interface_t {
  55
  56         /**
  57          * Get a SPI from the kernel.
  58          *
  59          * @param src           source address of SA
  60          * @param dst           destination address of SA
  61          * @param protocol      protocol for SA (ESP/AH)
  62          * @param reqid         unique ID for this SA
  63          * @param spi           allocated spi
  64          * @return                              SUCCESS if operation completed
  65          */
  66         status_t (*get_spi)(kernel_interface_t *this, host_t *src, host_t *dst,
  67                                                 protocol_id_t protocol, u_int32_t reqid, u_int32_t *spi);
  68
  69         /**
  70          * Get a Compression Parameter Index (CPI) from the kernel.
  71          *
  72          * @param src           source address of SA
  73          * @param dst           destination address of SA
  74          * @param reqid         unique ID for the corresponding SA
  75          * @param cpi           allocated cpi
  76          * @return                              SUCCESS if operation completed
  77          */
  78         status_t (*get_cpi)(kernel_interface_t *this, host_t *src, host_t *dst,
  79                                                 u_int32_t reqid, u_int16_t *cpi);
  80
  81         /**
  82          * Add an SA to the SAD.
  83          *
  84          * add_sa() may update an already allocated
  85          * SPI (via get_spi). In this case, the replace
  86          * flag must be set.
  87          * This function does install a single SA for a
  88          * single protocol in one direction. The kernel-interface
  89          * gets the keys itself from the PRF, as we don't know
  90          * his algorithms and key sizes.
  91          *
  92          * @param src                   source address for this SA
  93          * @param dst                   destination address for this SA
  94          * @param spi                   SPI allocated by us or remote peer
  95          * @param protocol              protocol for this SA (ESP/AH)
  96          * @param reqid                 unique ID for this SA
  97          * @param expire_soft   lifetime in seconds before rekeying
  98          * @param expire_hard   lifetime in seconds before delete
  99          * @param enc_alg               Algorithm to use for encryption (ESP only)
 100          * @param enc_key               key to use for encryption
 101          * @param int_alg               Algorithm to use for integrity protection
 102          * @param int_key               key to use for integrity protection
 103          * @param mode                  mode of the SA (tunnel, transport)
 104          * @param ipcomp                IPComp transform to use
 105          * @param cpi                   CPI for IPComp
 106          * @param encap                 enable UDP encapsulation for NAT traversal
 107          * @param inbound               TRUE if this is an inbound SA
 108          * @return                              SUCCESS if operation completed
 109          */
 110         status_t (*add_sa) (kernel_interface_t *this,
 111                                                 host_t *src, host_t *dst, u_int32_t spi,
 112                                                 protocol_id_t protocol, u_int32_t reqid,
 113                                                 u_int64_t expire_soft, u_int64_t expire_hard,
 114                                             u_int16_t enc_alg, chunk_t enc_key,
 115                                             u_int16_t int_alg, chunk_t int_key,
 116                                                 ipsec_mode_t mode, u_int16_t ipcomp, u_int16_t cpi,
 117                                                 bool encap, bool inbound);
 118
 119         /**
 120          * Update the hosts on an installed SA.
 121          *
 122          * We cannot directly update the destination address as the kernel
 123          * requires the spi, the protocol AND the destination address (and family)
 124          * to identify SAs. Therefore if the destination address changed we
 125          * create a new SA and delete the old one.
 126          *
 127          * @param spi                   SPI of the SA
 128          * @param protocol              protocol for this SA (ESP/AH)
 129          * @param cpi                   CPI for IPComp, 0 if no IPComp is used
 130          * @param src                   current source address
 131          * @param dst                   current destination address
 132          * @param new_src               new source address
 133          * @param new_dst               new destination address
 134          * @param encap                 current use of UDP encapsulation
 135          * @param new_encap             new use of UDP encapsulation
 136          * @return                              SUCCESS if operation completed, NOT_SUPPORTED if
 137          *                      the kernel interface can't update the SA
 138          */
 139         status_t (*update_sa)(kernel_interface_t *this,
 140                                                   u_int32_t spi, protocol_id_t protocol, u_int16_t cpi,
 141                                                   host_t *src, host_t *dst,
 142                                                   host_t *new_src, host_t *new_dst,
 143                                                   bool encap, bool new_encap);
 144
 145         /**
 146          * Delete a previously installed SA from the SAD.
 147          *
 148          * @param dst                   destination address for this SA
 149          * @param spi                   SPI allocated by us or remote peer
 150          * @param protocol              protocol for this SA (ESP/AH)
 151          * @param cpi                   CPI for IPComp or 0
 152          * @return                              SUCCESS if operation completed
 153          */
 154         status_t (*del_sa) (kernel_interface_t *this, host_t *dst, u_int32_t spi,
 155                                                 protocol_id_t protocol, u_int16_t cpi);
 156
 157         /**
 158          * Add a policy to the SPD.
 159          *
 160          * A policy is always associated to an SA. Traffic which matches a
 161          * policy is handled by the SA with the same reqid.
 162          *
 163          * @param src                   source address of SA
 164          * @param dst                   dest address of SA
 165          * @param src_ts                traffic selector to match traffic source
 166          * @param dst_ts                traffic selector to match traffic dest
 167          * @param direction             direction of traffic, POLICY_IN, POLICY_OUT, POLICY_FWD
 168          * @param spi                   SPI of SA
 169          * @param protocol              protocol to use to protect traffic (AH/ESP)
 170          * @param reqid                 unique ID of an SA to use to enforce policy
 171          * @param mode                  mode of SA (tunnel, transport)
 172          * @param ipcomp                the IPComp transform used
 173          * @param cpi                   CPI for IPComp
 174          * @param routed                TRUE, if this policy is routed in the kernel
 175          * @return                              SUCCESS if operation completed
 176          */
 177         status_t (*add_policy) (kernel_interface_t *this,
 178                                                         host_t *src, host_t *dst,
 179                                                         traffic_selector_t *src_ts,
 180                                                         traffic_selector_t *dst_ts,
 181                                                         policy_dir_t direction, u_int32_t spi,
 182                                                         protocol_id_t protocol, u_int32_t reqid,
 183                                                         ipsec_mode_t mode, u_int16_t ipcomp, u_int16_t cpi,
 184                                                         bool routed);
 185
 186         /**
 187          * Query the use time of a policy.
 188          *
 189          * The use time of a policy is the time the policy was used
 190          * for the last time.
 191          *
 192          * @param src_ts                traffic selector to match traffic source
 193          * @param dst_ts                traffic selector to match traffic dest
 194          * @param direction             direction of traffic, POLICY_IN, POLICY_OUT, POLICY_FWD
 195          * @param[out] use_time the time of this SA's last use
 196          * @return                              SUCCESS if operation completed
 197          */
 198         status_t (*query_policy) (kernel_interface_t *this,
 199                                                           traffic_selector_t *src_ts,
 200                                                           traffic_selector_t *dst_ts,
 201                                                           policy_dir_t direction, u_int32_t *use_time);
 202
 203         /**
 204          * Remove a policy from the SPD.
 205          *
 206          * The kernel interface implements reference counting for policies.
 207          * If the same policy is installed multiple times (in the case of rekeying),
 208          * the reference counter is increased. del_policy() decreases the ref counter
 209          * and removes the policy only when no more references are available.
 210          *
 211          * @param src_ts                traffic selector to match traffic source
 212          * @param dst_ts                traffic selector to match traffic dest
 213          * @param direction             direction of traffic, POLICY_IN, POLICY_OUT, POLICY_FWD
 214          * @param unrouted              TRUE, if this policy is unrouted from the kernel
 215          * @return                              SUCCESS if operation completed
 216          */
 217         status_t (*del_policy) (kernel_interface_t *this,
 218                                                         traffic_selector_t *src_ts,
 219                                                         traffic_selector_t *dst_ts,
 220                                                         policy_dir_t direction,
 221                                                         bool unrouted);
 222
 223         /**
 224          * Get our outgoing source address for a destination.
 225          *
 226          * Does a route lookup to get the source address used to reach dest.
 227          * The returned host is allocated and must be destroyed.
 228          * An optional src address can be used to check if a route is available
 229          * for given source to dest.
 230          *
 231          * @param dest                  target destination address
 232          * @param src                   source address to check, or NULL
 233          * @return                              outgoing source address, NULL if unreachable
 234          */
 235         host_t* (*get_source_addr)(kernel_interface_t *this,
 236                                                            host_t *dest, host_t *src);
 237
 238         /**
 239          * Get the next hop for a destination.
 240          *
 241          * Does a route lookup to get the next hop used to reach dest.
 242          * The returned host is allocated and must be destroyed.
 243          *
 244          * @param dest                  target destination address
 245          * @return                              next hop address, NULL if unreachable
 246          */
 247         host_t* (*get_nexthop)(kernel_interface_t *this, host_t *dest);
 248
 249         /**
 250          * Get the interface name of a local address.
 251          *
 252          * @param host                  address to get interface name from
 253          * @return                              allocated interface name, or NULL if not found
 254          */
 255         char* (*get_interface) (kernel_interface_t *this, host_t *host);
 256
 257         /**
 258          * Creates an enumerator over all local addresses.
 259          *
 260          * This function blocks an internal cached address list until the
 261          * enumerator gets destroyed.
 262          * The hosts are read-only, do not modify of free.
 263          *
 264          * @param include_down_ifaces   TRUE to enumerate addresses from down interfaces
 265          * @param include_virtual_ips   TRUE to enumerate virtual ip addresses
 266          * @return                                              enumerator over host_t's
 267          */
 268         enumerator_t *(*create_address_enumerator) (kernel_interface_t *this,
 269                                                 bool include_down_ifaces, bool include_virtual_ips);
 270
 271         /**
 272          * Add a virtual IP to an interface.
 273          *
 274          * Virtual IPs are attached to an interface. If an IP is added multiple
 275          * times, the IP is refcounted and not removed until del_ip() was called
 276          * as many times as add_ip().
 277          * The virtual IP is attached to the interface where the iface_ip is found.
 278          *
 279          * @param virtual_ip    virtual ip address to assign
 280          * @param iface_ip              IP of an interface to attach virtual IP
 281          * @return                              SUCCESS if operation completed
 282          */
 283         status_t (*add_ip) (kernel_interface_t *this, host_t *virtual_ip,
 284                                                 host_t *iface_ip);
 285
 286         /**
 287          * Remove a virtual IP from an interface.
 288          *
 289          * The kernel interface uses refcounting, see add_ip().
 290          *
 291          * @param virtual_ip    virtual ip address to assign
 292          * @return                              SUCCESS if operation completed
 293          */
 294         status_t (*del_ip) (kernel_interface_t *this, host_t *virtual_ip);
 295
 296         /**
 297          * Add a route.
 298          *
 299          * @param dst_net               destination net
 300          * @param prefixlen             destination net prefix length
 301          * @param gateway               gateway for this route
 302          * @param src_ip                sourc ip of the route
 303          * @param if_name               name of the interface the route is bound to
 304          * @return                              SUCCESS if operation completed
 305          *                                              ALREADY_DONE if the route already exists
 306          */
 307         status_t (*add_route) (kernel_interface_t *this, chunk_t dst_net, u_int8_t prefixlen,
 308                                                                 host_t *gateway, host_t *src_ip, char *if_name);
 309
 310         /**
 311          * Delete a route.
 312          *
 313          * @param dst_net               destination net
 314          * @param prefixlen             destination net prefix length
 315          * @param gateway               gateway for this route
 316          * @param src_ip                sourc ip of the route
 317          * @param if_name               name of the interface the route is bound to
 318          * @return                              SUCCESS if operation completed
 319          */
 320         status_t (*del_route) (kernel_interface_t *this, chunk_t dst_net, u_int8_t prefixlen,
 321                                                                 host_t *gateway, host_t *src_ip, char *if_name);
 322
 323         /**
 324          * manager methods
 325          */
 326
 327         /**
 328          * Tries to find an ip address of a local interface that is included in the
 329          * supplied traffic selector.
 330          *
 331          * @param ts                    traffic selector
 332          * @param ip                    returned ip (has to be destroyed)
 333          * @return                              SUCCESS if address found
 334          */
 335         status_t (*get_address_by_ts) (kernel_interface_t *this,
 336                                                                                 traffic_selector_t *ts, host_t **ip);
 337
 338         /**
 339          * Register an ipsec kernel interface constructor on the manager.
 340          *
 341          * @param create                        constructor to register
 342          */
 343         void (*add_ipsec_interface)(kernel_interface_t *this, kernel_ipsec_constructor_t create);
 344
 345         /**
 346          * Unregister an ipsec kernel interface constructor.
 347          *
 348          * @param create                        constructor to unregister
 349          */
 350         void (*remove_ipsec_interface)(kernel_interface_t *this, kernel_ipsec_constructor_t create);
 351
 352         /**
 353          * Register a network kernel interface constructor on the manager.
 354          *
 355          * @param create                        constructor to register
 356          */
 357         void (*add_net_interface)(kernel_interface_t *this, kernel_net_constructor_t create);
 358
 359         /**
 360          * Unregister a network kernel interface constructor.
 361          *
 362          * @param create                        constructor to unregister
 363          */
 364         void (*remove_net_interface)(kernel_interface_t *this, kernel_net_constructor_t create);
 365
 366         /**
 367          * Create the kernel interfaces classes.
 368          */
 369         void (*create_interfaces)(kernel_interface_t *this);
 370
 371         /**
 372          * Destroys a kernel_interface_manager_t object.
 373          */
 374         void (*destroy) (kernel_interface_t *this);
 375 };
 376
 377 /**
 378  * Creates an object of type kernel_interface_t.
 379  */
 380 kernel_interface_t *kernel_interface_create(void);
 381
 382 #endif /* KERNEL_INTERFACE_H_ @} */