Introduce "features" for the kernel backends returning kernel capabilities
[strongswan.git] / src / libhydra / kernel / kernel_interface.h
1 /*
2 * Copyright (C) 2006-2012 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 * Copyright (c) 2012 Nanoteq Pty Ltd
21 *
22 * Permission is hereby granted, free of charge, to any person obtaining a copy
23 * of this software and associated documentation files (the "Software"), to deal
24 * in the Software without restriction, including without limitation the rights
25 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
26 * copies of the Software, and to permit persons to whom the Software is
27 * furnished to do so, subject to the following conditions:
28 *
29 * The above copyright notice and this permission notice shall be included in
30 * all copies or substantial portions of the Software.
31 *
32 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
33 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
34 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
35 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
36 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
37 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
38 * THE SOFTWARE.
39 */
40
41 /**
42 * @defgroup kernel_interface kernel_interface
43 * @{ @ingroup hkernel
44 */
45
46 #ifndef KERNEL_INTERFACE_H_
47 #define KERNEL_INTERFACE_H_
48
49 typedef struct kernel_interface_t kernel_interface_t;
50 typedef enum kernel_feature_t kernel_feature_t;
51
52 #include <networking/host.h>
53 #include <crypto/prf_plus.h>
54
55 #include <kernel/kernel_listener.h>
56 #include <kernel/kernel_ipsec.h>
57 #include <kernel/kernel_net.h>
58
59 /**
60 * Bitfield of optional features a kernel backend supports.
61 *
62 * This feature-set is for both, kernel_ipsec_t and kernel_net_t. Each
63 * backend returns a subset of these features.
64 */
65 enum kernel_feature_t {
66 /** IPsec can process ESPv3 (RFC 4303) TFC padded packets */
67 KERNEL_ESP_V3_TFC = (1<<0),
68 };
69
70 /**
71 * Constructor function for ipsec kernel interface
72 */
73 typedef kernel_ipsec_t* (*kernel_ipsec_constructor_t)(void);
74
75 /**
76 * Constructor function for network kernel interface
77 */
78 typedef kernel_net_t* (*kernel_net_constructor_t)(void);
79
80 /**
81 * Manager and wrapper for different kernel interfaces.
82 *
83 * The kernel interface handles the communication with the kernel
84 * for SA and policy management and interface and IP address management.
85 */
86 struct kernel_interface_t {
87
88 /**
89 * Get the feature set supported by the net and ipsec kernel backends.
90 *
91 * @return ORed feature-set of backends
92 */
93 kernel_feature_t (*get_features)(kernel_interface_t *this);
94
95 /**
96 * Get a SPI from the kernel.
97 *
98 * @param src source address of SA
99 * @param dst destination address of SA
100 * @param protocol protocol for SA (ESP/AH)
101 * @param reqid unique ID for this SA
102 * @param spi allocated spi
103 * @return SUCCESS if operation completed
104 */
105 status_t (*get_spi)(kernel_interface_t *this, host_t *src, host_t *dst,
106 u_int8_t protocol, u_int32_t reqid, u_int32_t *spi);
107
108 /**
109 * Get a Compression Parameter Index (CPI) from the kernel.
110 *
111 * @param src source address of SA
112 * @param dst destination address of SA
113 * @param reqid unique ID for the corresponding SA
114 * @param cpi allocated cpi
115 * @return SUCCESS if operation completed
116 */
117 status_t (*get_cpi)(kernel_interface_t *this, host_t *src, host_t *dst,
118 u_int32_t reqid, u_int16_t *cpi);
119
120 /**
121 * Add an SA to the SAD.
122 *
123 * add_sa() may update an already allocated
124 * SPI (via get_spi). In this case, the replace
125 * flag must be set.
126 * This function does install a single SA for a
127 * single protocol in one direction.
128 *
129 * @param src source address for this SA
130 * @param dst destination address for this SA
131 * @param spi SPI allocated by us or remote peer
132 * @param protocol protocol for this SA (ESP/AH)
133 * @param reqid unique ID for this SA
134 * @param mark optional mark for this SA
135 * @param tfc Traffic Flow Confidentiality padding for this SA
136 * @param lifetime lifetime_cfg_t for this SA
137 * @param enc_alg Algorithm to use for encryption (ESP only)
138 * @param enc_key key to use for encryption
139 * @param int_alg Algorithm to use for integrity protection
140 * @param int_key key to use for integrity protection
141 * @param mode mode of the SA (tunnel, transport)
142 * @param ipcomp IPComp transform to use
143 * @param cpi CPI for IPComp
144 * @param encap enable UDP encapsulation for NAT traversal
145 * @param esn TRUE to use Extended Sequence Numbers
146 * @param inbound TRUE if this is an inbound SA
147 * @param src_ts traffic selector with BEET source address
148 * @param dst_ts traffic selector with BEET destination address
149 * @return SUCCESS if operation completed
150 */
151 status_t (*add_sa) (kernel_interface_t *this,
152 host_t *src, host_t *dst, u_int32_t spi,
153 u_int8_t protocol, u_int32_t reqid, mark_t mark,
154 u_int32_t tfc, lifetime_cfg_t *lifetime,
155 u_int16_t enc_alg, chunk_t enc_key,
156 u_int16_t int_alg, chunk_t int_key,
157 ipsec_mode_t mode, u_int16_t ipcomp, u_int16_t cpi,
158 bool encap, bool esn, bool inbound,
159 traffic_selector_t *src_ts, traffic_selector_t *dst_ts);
160
161 /**
162 * Update the hosts on an installed SA.
163 *
164 * We cannot directly update the destination address as the kernel
165 * requires the spi, the protocol AND the destination address (and family)
166 * to identify SAs. Therefore if the destination address changed we
167 * create a new SA and delete the old one.
168 *
169 * @param spi SPI of the SA
170 * @param protocol protocol for this SA (ESP/AH)
171 * @param cpi CPI for IPComp, 0 if no IPComp is used
172 * @param src current source address
173 * @param dst current destination address
174 * @param new_src new source address
175 * @param new_dst new destination address
176 * @param encap current use of UDP encapsulation
177 * @param new_encap new use of UDP encapsulation
178 * @param mark optional mark for this SA
179 * @return SUCCESS if operation completed, NOT_SUPPORTED if
180 * the kernel interface can't update the SA
181 */
182 status_t (*update_sa)(kernel_interface_t *this,
183 u_int32_t spi, u_int8_t protocol, u_int16_t cpi,
184 host_t *src, host_t *dst,
185 host_t *new_src, host_t *new_dst,
186 bool encap, bool new_encap, mark_t mark);
187
188 /**
189 * Query the number of bytes processed by an SA from the SAD.
190 *
191 * @param src source address for this SA
192 * @param dst destination address for this SA
193 * @param spi SPI allocated by us or remote peer
194 * @param protocol protocol for this SA (ESP/AH)
195 * @param mark optional mark for this SA
196 * @param[out] bytes the number of bytes processed by SA
197 * @return SUCCESS if operation completed
198 */
199 status_t (*query_sa) (kernel_interface_t *this, host_t *src, host_t *dst,
200 u_int32_t spi, u_int8_t protocol, mark_t mark,
201 u_int64_t *bytes);
202
203 /**
204 * Delete a previously installed SA from the SAD.
205 *
206 * @param src source address for this SA
207 * @param dst destination address for this SA
208 * @param spi SPI allocated by us or remote peer
209 * @param protocol protocol for this SA (ESP/AH)
210 * @param cpi CPI for IPComp or 0
211 * @param mark optional mark for this SA
212 * @return SUCCESS if operation completed
213 */
214 status_t (*del_sa) (kernel_interface_t *this, host_t *src, host_t *dst,
215 u_int32_t spi, u_int8_t protocol, u_int16_t cpi,
216 mark_t mark);
217
218 /**
219 * Flush all SAs from the SAD.
220 *
221 * @return SUCCESS if operation completed
222 */
223 status_t (*flush_sas) (kernel_interface_t *this);
224
225 /**
226 * Add a policy to the SPD.
227 *
228 * A policy is always associated to an SA. Traffic which matches a
229 * policy is handled by the SA with the same reqid.
230 *
231 * @param src source address of SA
232 * @param dst dest address of SA
233 * @param src_ts traffic selector to match traffic source
234 * @param dst_ts traffic selector to match traffic dest
235 * @param direction direction of traffic, POLICY_(IN|OUT|FWD)
236 * @param type type of policy, POLICY_(IPSEC|PASS|DROP)
237 * @param sa details about the SA(s) tied to this policy
238 * @param mark mark for this policy
239 * @param priority priority of this policy
240 * @return SUCCESS if operation completed
241 */
242 status_t (*add_policy) (kernel_interface_t *this,
243 host_t *src, host_t *dst,
244 traffic_selector_t *src_ts,
245 traffic_selector_t *dst_ts,
246 policy_dir_t direction, policy_type_t type,
247 ipsec_sa_cfg_t *sa, mark_t mark,
248 policy_priority_t priority);
249
250 /**
251 * Query the use time of a policy.
252 *
253 * The use time of a policy is the time the policy was used
254 * for the last time.
255 *
256 * @param src_ts traffic selector to match traffic source
257 * @param dst_ts traffic selector to match traffic dest
258 * @param direction direction of traffic, POLICY_(IN|OUT|FWD)
259 * @param mark optional mark
260 * @param[out] use_time the time of this SA's last use
261 * @return SUCCESS if operation completed
262 */
263 status_t (*query_policy) (kernel_interface_t *this,
264 traffic_selector_t *src_ts,
265 traffic_selector_t *dst_ts,
266 policy_dir_t direction, mark_t mark,
267 u_int32_t *use_time);
268
269 /**
270 * Remove a policy from the SPD.
271 *
272 * The kernel interface implements reference counting for policies.
273 * If the same policy is installed multiple times (in the case of rekeying),
274 * the reference counter is increased. del_policy() decreases the ref counter
275 * and removes the policy only when no more references are available.
276 *
277 * @param src_ts traffic selector to match traffic source
278 * @param dst_ts traffic selector to match traffic dest
279 * @param direction direction of traffic, POLICY_(IN|OUT|FWD)
280 * @param reqid unique ID of the associated SA
281 * @param mark optional mark
282 * @param priority priority of the policy
283 * @return SUCCESS if operation completed
284 */
285 status_t (*del_policy) (kernel_interface_t *this,
286 traffic_selector_t *src_ts,
287 traffic_selector_t *dst_ts,
288 policy_dir_t direction, u_int32_t reqid,
289 mark_t mark, policy_priority_t priority);
290
291 /**
292 * Flush all policies from the SPD.
293 *
294 * @return SUCCESS if operation completed
295 */
296 status_t (*flush_policies) (kernel_interface_t *this);
297
298 /**
299 * Get our outgoing source address for a destination.
300 *
301 * Does a route lookup to get the source address used to reach dest.
302 * The returned host is allocated and must be destroyed.
303 * An optional src address can be used to check if a route is available
304 * for the given source to dest.
305 *
306 * @param dest target destination address
307 * @param src source address to check, or NULL
308 * @return outgoing source address, NULL if unreachable
309 */
310 host_t* (*get_source_addr)(kernel_interface_t *this,
311 host_t *dest, host_t *src);
312
313 /**
314 * Get the next hop for a destination.
315 *
316 * Does a route lookup to get the next hop used to reach dest.
317 * The returned host is allocated and must be destroyed.
318 * An optional src address can be used to check if a route is available
319 * for the given source to dest.
320 *
321 * @param dest target destination address
322 * @return next hop address, NULL if unreachable
323 */
324 host_t* (*get_nexthop)(kernel_interface_t *this, host_t *dest, host_t *src);
325
326 /**
327 * Get the interface name of a local address. Interfaces that are down or
328 * ignored by config are not considered.
329 *
330 * @param host address to get interface name from
331 * @param name allocated interface name (optional)
332 * @return TRUE if interface found and usable
333 */
334 bool (*get_interface)(kernel_interface_t *this, host_t *host, char **name);
335
336 /**
337 * Creates an enumerator over all local addresses.
338 *
339 * This function blocks an internal cached address list until the
340 * enumerator gets destroyed.
341 * The hosts are read-only, do not modify of free.
342 *
343 * @param which a combination of address types to enumerate
344 * @return enumerator over host_t's
345 */
346 enumerator_t *(*create_address_enumerator) (kernel_interface_t *this,
347 kernel_address_type_t which);
348
349 /**
350 * Add a virtual IP to an interface.
351 *
352 * Virtual IPs are attached to an interface. If an IP is added multiple
353 * times, the IP is refcounted and not removed until del_ip() was called
354 * as many times as add_ip().
355 *
356 * @param virtual_ip virtual ip address to assign
357 * @param prefix prefix length to install IP with, -1 for auto
358 * @param iface interface to install virtual IP on
359 * @return SUCCESS if operation completed
360 */
361 status_t (*add_ip) (kernel_interface_t *this, host_t *virtual_ip, int prefix,
362 char *iface);
363
364 /**
365 * Remove a virtual IP from an interface.
366 *
367 * The kernel interface uses refcounting, see add_ip().
368 *
369 * @param virtual_ip virtual ip address to assign
370 * @param prefix prefix length of the IP to uninstall, -1 for auto
371 * @param wait TRUE to wait untily IP is gone
372 * @return SUCCESS if operation completed
373 */
374 status_t (*del_ip) (kernel_interface_t *this, host_t *virtual_ip,
375 int prefix, bool wait);
376
377 /**
378 * Add a route.
379 *
380 * @param dst_net destination net
381 * @param prefixlen destination net prefix length
382 * @param gateway gateway for this route
383 * @param src_ip sourc ip of the route
384 * @param if_name name of the interface the route is bound to
385 * @return SUCCESS if operation completed
386 * ALREADY_DONE if the route already exists
387 */
388 status_t (*add_route) (kernel_interface_t *this, chunk_t dst_net,
389 u_int8_t prefixlen, host_t *gateway, host_t *src_ip,
390 char *if_name);
391
392 /**
393 * Delete a route.
394 *
395 * @param dst_net destination net
396 * @param prefixlen destination net prefix length
397 * @param gateway gateway for this route
398 * @param src_ip sourc ip of the route
399 * @param if_name name of the interface the route is bound to
400 * @return SUCCESS if operation completed
401 */
402 status_t (*del_route) (kernel_interface_t *this, chunk_t dst_net,
403 u_int8_t prefixlen, host_t *gateway, host_t *src_ip,
404 char *if_name);
405
406 /**
407 * Set up a bypass policy for a given socket.
408 *
409 * @param fd socket file descriptor to setup policy for
410 * @param family protocol family of the socket
411 * @return TRUE if policy set up successfully
412 */
413 bool (*bypass_socket)(kernel_interface_t *this, int fd, int family);
414
415 /**
416 * Enable decapsulation of ESP-in-UDP packets for the given port/socket.
417 *
418 * @param fd socket file descriptor
419 * @param family protocol family of the socket
420 * @param port the UDP port
421 * @return TRUE if UDP decapsulation was enabled successfully
422 */
423 bool (*enable_udp_decap)(kernel_interface_t *this, int fd, int family,
424 u_int16_t port);
425
426
427 /**
428 * manager methods
429 */
430
431 /**
432 * Verifies that the given interface is usable and not excluded by
433 * configuration.
434 *
435 * @param iface interface name
436 * @return TRUE if usable
437 */
438 bool (*is_interface_usable)(kernel_interface_t *this, const char *iface);
439
440 /**
441 * Check if interfaces are excluded by config.
442 *
443 * @return TRUE if no interfaces are exclued by config
444 */
445 bool (*all_interfaces_usable)(kernel_interface_t *this);
446
447 /**
448 * Tries to find an IP address of a local interface that is included in the
449 * supplied traffic selector.
450 *
451 * @param ts traffic selector
452 * @param ip returned IP address (has to be destroyed)
453 * @return SUCCESS if address found
454 */
455 status_t (*get_address_by_ts)(kernel_interface_t *this,
456 traffic_selector_t *ts, host_t **ip);
457
458 /**
459 * Register an ipsec kernel interface constructor on the manager.
460 *
461 * @param create constructor to register
462 */
463 void (*add_ipsec_interface)(kernel_interface_t *this,
464 kernel_ipsec_constructor_t create);
465
466 /**
467 * Unregister an ipsec kernel interface constructor.
468 *
469 * @param create constructor to unregister
470 */
471 void (*remove_ipsec_interface)(kernel_interface_t *this,
472 kernel_ipsec_constructor_t create);
473
474 /**
475 * Register a network kernel interface constructor on the manager.
476 *
477 * @param create constructor to register
478 */
479 void (*add_net_interface)(kernel_interface_t *this,
480 kernel_net_constructor_t create);
481
482 /**
483 * Unregister a network kernel interface constructor.
484 *
485 * @param create constructor to unregister
486 */
487 void (*remove_net_interface)(kernel_interface_t *this,
488 kernel_net_constructor_t create);
489
490 /**
491 * Add a listener to the kernel interface.
492 *
493 * @param listener listener to add
494 */
495 void (*add_listener)(kernel_interface_t *this,
496 kernel_listener_t *listener);
497
498 /**
499 * Remove a listener from the kernel interface.
500 *
501 * @param listener listener to remove
502 */
503 void (*remove_listener)(kernel_interface_t *this,
504 kernel_listener_t *listener);
505
506 /**
507 * Raise an acquire event.
508 *
509 * @param reqid reqid of the policy to acquire
510 * @param src_ts source traffic selector
511 * @param dst_ts destination traffic selector
512 */
513 void (*acquire)(kernel_interface_t *this, u_int32_t reqid,
514 traffic_selector_t *src_ts, traffic_selector_t *dst_ts);
515
516 /**
517 * Raise an expire event.
518 *
519 * @param reqid reqid of the expired SA
520 * @param protocol protocol of the expired SA
521 * @param spi spi of the expired SA
522 * @param hard TRUE if it is a hard expire, FALSE otherwise
523 */
524 void (*expire)(kernel_interface_t *this, u_int32_t reqid,
525 u_int8_t protocol, u_int32_t spi, bool hard);
526
527 /**
528 * Raise a mapping event.
529 *
530 * @param reqid reqid of the SA
531 * @param spi spi of the SA
532 * @param remote new remote host
533 */
534 void (*mapping)(kernel_interface_t *this, u_int32_t reqid, u_int32_t spi,
535 host_t *remote);
536
537 /**
538 * Raise a migrate event.
539 *
540 * @param reqid reqid of the policy
541 * @param src_ts source traffic selector
542 * @param dst_ts destination traffic selector
543 * @param direction direction of the policy (in|out)
544 * @param local local host address to be used in the IKE_SA
545 * @param remote remote host address to be used in the IKE_SA
546 */
547 void (*migrate)(kernel_interface_t *this, u_int32_t reqid,
548 traffic_selector_t *src_ts, traffic_selector_t *dst_ts,
549 policy_dir_t direction, host_t *local, host_t *remote);
550
551 /**
552 * Raise a roam event.
553 *
554 * @param address TRUE if address list, FALSE if routing changed
555 */
556 void (*roam)(kernel_interface_t *this, bool address);
557
558 /**
559 * Register a new algorithm with the kernel interface.
560 *
561 * @param alg_id the IKE id of the algorithm
562 * @param type the transform type of the algorithm
563 * @param kernel_id the kernel id of the algorithm
564 * @param kernel_name the kernel name of the algorithm
565 */
566 void (*register_algorithm)(kernel_interface_t *this, u_int16_t alg_id,
567 transform_type_t type, u_int16_t kernel_id,
568 char *kernel_name);
569
570 /**
571 * Return the kernel-specific id and/or name for an algorithms depending on
572 * the arguments specified.
573 *
574 * @param alg_id the IKE id of the algorithm
575 * @param type the transform type of the algorithm
576 * @param kernel_id the kernel id of the algorithm (optional)
577 * @param kernel_name the kernel name of the algorithm (optional)
578 * @return TRUE if algorithm was found
579 */
580 bool (*lookup_algorithm)(kernel_interface_t *this, u_int16_t alg_id,
581 transform_type_t type, u_int16_t *kernel_id,
582 char **kernel_name);
583
584 /**
585 * Destroys a kernel_interface_manager_t object.
586 */
587 void (*destroy) (kernel_interface_t *this);
588 };
589
590 /**
591 * Creates an object of type kernel_interface_t.
592 */
593 kernel_interface_t *kernel_interface_create(void);
594
595 #endif /** KERNEL_INTERFACE_H_ @}*/