src/libcharon/kernel/kernel_interface.h

   1 /*
   2  * Copyright (C) 2006-2009 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
  19 /**
  20  * @defgroup kernel_interface kernel_interface
  21  * @{ @ingroup kernel
  22  */
  23
  24 #ifndef KERNEL_INTERFACE_H_
  25 #define KERNEL_INTERFACE_H_
  26
  27 typedef struct kernel_interface_t kernel_interface_t;
  28
  29 #include <utils/host.h>
  30 #include <crypto/prf_plus.h>
  31 #include <encoding/payloads/proposal_substructure.h>
  32
  33 #include <kernel/kernel_ipsec.h>
  34 #include <kernel/kernel_net.h>
  35
  36 /**
  37  * Constructor function for ipsec kernel interface
  38  */
  39 typedef kernel_ipsec_t* (*kernel_ipsec_constructor_t)(void);
  40
  41 /**
  42  * Constructor function for network kernel interface
  43  */
  44 typedef kernel_net_t* (*kernel_net_constructor_t)(void);
  45
  46 /**
  47  * Manager and wrapper for different kernel interfaces.
  48  *
  49  * The kernel interface handles the communication with the kernel
  50  * for SA and policy management and interface and IP address management.
  51  */
  52 struct kernel_interface_t {
  53
  54         /**
  55          * Get a SPI from the kernel.
  56          *
  57          * @param src           source address of SA
  58          * @param dst           destination address of SA
  59          * @param protocol      protocol for SA (ESP/AH)
  60          * @param reqid         unique ID for this SA
  61          * @param spi           allocated spi
  62          * @return                              SUCCESS if operation completed
  63          */
  64         status_t (*get_spi)(kernel_interface_t *this, host_t *src, host_t *dst,
  65                                                 protocol_id_t protocol, u_int32_t reqid, u_int32_t *spi);
  66
  67         /**
  68          * Get a Compression Parameter Index (CPI) from the kernel.
  69          *
  70          * @param src           source address of SA
  71          * @param dst           destination address of SA
  72          * @param reqid         unique ID for the corresponding SA
  73          * @param cpi           allocated cpi
  74          * @return                              SUCCESS if operation completed
  75          */
  76         status_t (*get_cpi)(kernel_interface_t *this, host_t *src, host_t *dst,
  77                                                 u_int32_t reqid, u_int16_t *cpi);
  78
  79         /**
  80          * Add an SA to the SAD.
  81          *
  82          * add_sa() may update an already allocated
  83          * SPI (via get_spi). In this case, the replace
  84          * flag must be set.
  85          * This function does install a single SA for a
  86          * single protocol in one direction.
  87          *
  88          * @param src                   source address for this SA
  89          * @param dst                   destination address for this SA
  90          * @param spi                   SPI allocated by us or remote peer
  91          * @param protocol              protocol for this SA (ESP/AH)
  92          * @param reqid                 unique ID for this SA
  93          * @param mark                  optional mark for this SA
  94          * @param lifetime              lifetime_cfg_t for this SA
  95          * @param enc_alg               Algorithm to use for encryption (ESP only)
  96          * @param enc_key               key to use for encryption
  97          * @param int_alg               Algorithm to use for integrity protection
  98          * @param int_key               key to use for integrity protection
  99          * @param mode                  mode of the SA (tunnel, transport)
 100          * @param ipcomp                IPComp transform to use
 101          * @param cpi                   CPI for IPComp
 102          * @param encap                 enable UDP encapsulation for NAT traversal
 103          * @param inbound               TRUE if this is an inbound SA
 104          * @param src_ts                traffic selector with BEET source address
 105          * @param dst_ts                traffic selector with BEET destination address
 106          * @return                              SUCCESS if operation completed
 107          */
 108         status_t (*add_sa) (kernel_interface_t *this,
 109                                                 host_t *src, host_t *dst, u_int32_t spi,
 110                                                 protocol_id_t protocol, u_int32_t reqid, mark_t mark,
 111                                                 lifetime_cfg_t *lifetime,
 112                                                 u_int16_t enc_alg, chunk_t enc_key,
 113                                                 u_int16_t int_alg, chunk_t int_key,
 114                                                 ipsec_mode_t mode, u_int16_t ipcomp, u_int16_t cpi,
 115                                                 bool encap, bool inbound,
 116                                                 traffic_selector_t *src_ts, traffic_selector_t *dst_ts);
 117
 118         /**
 119          * Update the hosts on an installed SA.
 120          *
 121          * We cannot directly update the destination address as the kernel
 122          * requires the spi, the protocol AND the destination address (and family)
 123          * to identify SAs. Therefore if the destination address changed we
 124          * create a new SA and delete the old one.
 125          *
 126          * @param spi                   SPI of the SA
 127          * @param protocol              protocol for this SA (ESP/AH)
 128          * @param cpi                   CPI for IPComp, 0 if no IPComp is used
 129          * @param src                   current source address
 130          * @param dst                   current destination address
 131          * @param new_src               new source address
 132          * @param new_dst               new destination address
 133          * @param encap                 current use of UDP encapsulation
 134          * @param new_encap             new use of UDP encapsulation
 135          * @param mark                  optional mark for this SA
 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, mark_t mark);
 144
 145         /**
 146          * Query the number of bytes processed by an SA from the SAD.
 147          *
 148          * @param src                   source address for this SA
 149          * @param dst                   destination address for this SA
 150          * @param spi                   SPI allocated by us or remote peer
 151          * @param protocol              protocol for this SA (ESP/AH)
 152          * @param mark                  optional mark for this SA
 153          * @param[out] bytes    the number of bytes processed by SA
 154          * @return                              SUCCESS if operation completed
 155          */
 156         status_t (*query_sa) (kernel_interface_t *this, host_t *src, host_t *dst,
 157                                                   u_int32_t spi, protocol_id_t protocol, mark_t mark,
 158                                                   u_int64_t *bytes);
 159
 160         /**
 161          * Delete a previously installed SA from the SAD.
 162          *
 163          * @param src                   source address for this SA
 164          * @param dst                   destination address for this SA
 165          * @param spi                   SPI allocated by us or remote peer
 166          * @param protocol              protocol for this SA (ESP/AH)
 167          * @param cpi                   CPI for IPComp or 0
 168          * @param mark                  optional mark for this SA
 169          * @return                              SUCCESS if operation completed
 170          */
 171         status_t (*del_sa) (kernel_interface_t *this, host_t *src, host_t *dst,
 172                                                 u_int32_t spi, protocol_id_t protocol, u_int16_t cpi,
 173                                                 mark_t mark);
 174
 175         /**
 176          * Add a policy to the SPD.
 177          *
 178          * A policy is always associated to an SA. Traffic which matches a
 179          * policy is handled by the SA with the same reqid.
 180          *
 181          * @param src                   source address of SA
 182          * @param dst                   dest address of SA
 183          * @param src_ts                traffic selector to match traffic source
 184          * @param dst_ts                traffic selector to match traffic dest
 185          * @param direction             direction of traffic, POLICY_IN, POLICY_OUT, POLICY_FWD
 186          * @param spi                   SPI of SA
 187          * @param protocol              protocol to use to protect traffic (AH/ESP)
 188          * @param reqid                 unique ID of an SA to use to enforce policy
 189          * @param mark                  mark for this policy
 190          * @param mode                  mode of SA (tunnel, transport)
 191          * @param ipcomp                the IPComp transform used
 192          * @param cpi                   CPI for IPComp
 193          * @param routed                TRUE, if this policy is routed in the kernel
 194          * @return                              SUCCESS if operation completed
 195          */
 196         status_t (*add_policy) (kernel_interface_t *this,
 197                                                         host_t *src, host_t *dst,
 198                                                         traffic_selector_t *src_ts,
 199                                                         traffic_selector_t *dst_ts,
 200                                                         policy_dir_t direction, u_int32_t spi,
 201                                                         protocol_id_t protocol, u_int32_t reqid,
 202                                                         mark_t mark, ipsec_mode_t mode, u_int16_t ipcomp,
 203                                                         u_int16_t cpi, bool routed);
 204
 205         /**
 206          * Query the use time of a policy.
 207          *
 208          * The use time of a policy is the time the policy was used
 209          * for the last time.
 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 mark                  optional mark
 215          * @param[out] use_time the time of this SA's last use
 216          * @return                              SUCCESS if operation completed
 217          */
 218         status_t (*query_policy) (kernel_interface_t *this,
 219                                                           traffic_selector_t *src_ts,
 220                                                           traffic_selector_t *dst_ts,
 221                                                           policy_dir_t direction, mark_t mark,
 222                                                           u_int32_t *use_time);
 223
 224         /**
 225          * Remove a policy from the SPD.
 226          *
 227          * The kernel interface implements reference counting for policies.
 228          * If the same policy is installed multiple times (in the case of rekeying),
 229          * the reference counter is increased. del_policy() decreases the ref counter
 230          * and removes the policy only when no more references are available.
 231          *
 232          * @param src_ts                traffic selector to match traffic source
 233          * @param dst_ts                traffic selector to match traffic dest
 234          * @param direction             direction of traffic, POLICY_IN, POLICY_OUT, POLICY_FWD
 235          * @param mark                  optional mark
 236          * @param unrouted              TRUE, if this policy is unrouted from the kernel
 237          * @return                              SUCCESS if operation completed
 238          */
 239         status_t (*del_policy) (kernel_interface_t *this,
 240                                                         traffic_selector_t *src_ts,
 241                                                         traffic_selector_t *dst_ts,
 242                                                         policy_dir_t direction, mark_t mark,
 243                                                         bool unrouted);
 244
 245         /**
 246          * Get our outgoing source address for a destination.
 247          *
 248          * Does a route lookup to get the source address used to reach dest.
 249          * The returned host is allocated and must be destroyed.
 250          * An optional src address can be used to check if a route is available
 251          * for given source to dest.
 252          *
 253          * @param dest                  target destination address
 254          * @param src                   source address to check, or NULL
 255          * @return                              outgoing source address, NULL if unreachable
 256          */
 257         host_t* (*get_source_addr)(kernel_interface_t *this,
 258                                                            host_t *dest, host_t *src);
 259
 260         /**
 261          * Get the next hop for a destination.
 262          *
 263          * Does a route lookup to get the next hop used to reach dest.
 264          * The returned host is allocated and must be destroyed.
 265          *
 266          * @param dest                  target destination address
 267          * @return                              next hop address, NULL if unreachable
 268          */
 269         host_t* (*get_nexthop)(kernel_interface_t *this, host_t *dest);
 270
 271         /**
 272          * Get the interface name of a local address.
 273          *
 274          * @param host                  address to get interface name from
 275          * @return                              allocated interface name, or NULL if not found
 276          */
 277         char* (*get_interface) (kernel_interface_t *this, host_t *host);
 278
 279         /**
 280          * Creates an enumerator over all local addresses.
 281          *
 282          * This function blocks an internal cached address list until the
 283          * enumerator gets destroyed.
 284          * The hosts are read-only, do not modify of free.
 285          *
 286          * @param include_down_ifaces   TRUE to enumerate addresses from down interfaces
 287          * @param include_virtual_ips   TRUE to enumerate virtual ip addresses
 288          * @return                                              enumerator over host_t's
 289          */
 290         enumerator_t *(*create_address_enumerator) (kernel_interface_t *this,
 291                                                 bool include_down_ifaces, bool include_virtual_ips);
 292
 293         /**
 294          * Add a virtual IP to an interface.
 295          *
 296          * Virtual IPs are attached to an interface. If an IP is added multiple
 297          * times, the IP is refcounted and not removed until del_ip() was called
 298          * as many times as add_ip().
 299          * The virtual IP is attached to the interface where the iface_ip is found.
 300          *
 301          * @param virtual_ip    virtual ip address to assign
 302          * @param iface_ip              IP of an interface to attach virtual IP
 303          * @return                              SUCCESS if operation completed
 304          */
 305         status_t (*add_ip) (kernel_interface_t *this, host_t *virtual_ip,
 306                                                 host_t *iface_ip);
 307
 308         /**
 309          * Remove a virtual IP from an interface.
 310          *
 311          * The kernel interface uses refcounting, see add_ip().
 312          *
 313          * @param virtual_ip    virtual ip address to assign
 314          * @return                              SUCCESS if operation completed
 315          */
 316         status_t (*del_ip) (kernel_interface_t *this, host_t *virtual_ip);
 317
 318         /**
 319          * Add a route.
 320          *
 321          * @param dst_net               destination net
 322          * @param prefixlen             destination net prefix length
 323          * @param gateway               gateway for this route
 324          * @param src_ip                sourc ip of the route
 325          * @param if_name               name of the interface the route is bound to
 326          * @return                              SUCCESS if operation completed
 327          *                                              ALREADY_DONE if the route already exists
 328          */
 329         status_t (*add_route) (kernel_interface_t *this, chunk_t dst_net, u_int8_t prefixlen,
 330                                                                 host_t *gateway, host_t *src_ip, char *if_name);
 331
 332         /**
 333          * Delete a route.
 334          *
 335          * @param dst_net               destination net
 336          * @param prefixlen             destination net prefix length
 337          * @param gateway               gateway for this route
 338          * @param src_ip                sourc ip of the route
 339          * @param if_name               name of the interface the route is bound to
 340          * @return                              SUCCESS if operation completed
 341          */
 342         status_t (*del_route) (kernel_interface_t *this, chunk_t dst_net, u_int8_t prefixlen,
 343                                                                 host_t *gateway, host_t *src_ip, char *if_name);
 344
 345         /**
 346          * Set up a bypass policy for a given socket.
 347          *
 348          * @param fd                    socket file descriptor to setup policy for
 349          * @param family                protocol family of the socket
 350          * @return                              TRUE of policy set up successfully
 351          */
 352         bool (*bypass_socket)(kernel_interface_t *this, int fd, int family);
 353
 354         /**
 355          * manager methods
 356          */
 357
 358         /**
 359          * Tries to find an ip address of a local interface that is included in the
 360          * supplied traffic selector.
 361          *
 362          * @param ts                    traffic selector
 363          * @param ip                    returned ip (has to be destroyed)
 364          * @return                              SUCCESS if address found
 365          */
 366         status_t (*get_address_by_ts) (kernel_interface_t *this,
 367                                                                                 traffic_selector_t *ts, host_t **ip);
 368
 369         /**
 370          * Register an ipsec kernel interface constructor on the manager.
 371          *
 372          * @param create                        constructor to register
 373          */
 374         void (*add_ipsec_interface)(kernel_interface_t *this, kernel_ipsec_constructor_t create);
 375
 376         /**
 377          * Unregister an ipsec kernel interface constructor.
 378          *
 379          * @param create                        constructor to unregister
 380          */
 381         void (*remove_ipsec_interface)(kernel_interface_t *this, kernel_ipsec_constructor_t create);
 382
 383         /**
 384          * Register a network kernel interface constructor on the manager.
 385          *
 386          * @param create                        constructor to register
 387          */
 388         void (*add_net_interface)(kernel_interface_t *this, kernel_net_constructor_t create);
 389
 390         /**
 391          * Unregister a network kernel interface constructor.
 392          *
 393          * @param create                        constructor to unregister
 394          */
 395         void (*remove_net_interface)(kernel_interface_t *this, kernel_net_constructor_t create);
 396
 397         /**
 398          * Destroys a kernel_interface_manager_t object.
 399          */
 400         void (*destroy) (kernel_interface_t *this);
 401 };
 402
 403 /**
 404  * Creates an object of type kernel_interface_t.
 405  */
 406 kernel_interface_t *kernel_interface_create(void);
 407
 408 #endif /** KERNEL_INTERFACE_H_ @}*/