ike-sa-manager: Remove IKE_SA checkout by CHILD_SA reqid
[strongswan.git] / src / libcharon / sa / ike_sa_manager.h
1 /*
2 * Copyright (C) 2008 Tobias Brunner
3 * Copyright (C) 2005-2008 Martin Willi
4 * Copyright (C) 2005 Jan Hutter
5 * Hochschule fuer Technik Rapperswil
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 */
17
18 /**
19 * @defgroup ike_sa_manager ike_sa_manager
20 * @{ @ingroup sa
21 */
22
23 #ifndef IKE_SA_MANAGER_H_
24 #define IKE_SA_MANAGER_H_
25
26 typedef struct ike_sa_manager_t ike_sa_manager_t;
27
28 #include <library.h>
29 #include <sa/ike_sa.h>
30 #include <encoding/message.h>
31 #include <config/peer_cfg.h>
32
33 /**
34 * Manages and synchronizes access to all IKE_SAs.
35 *
36 * To synchronize access to thread-unsave IKE_SAs, they are checked out for
37 * use and checked in afterwards. A checked out SA is exclusively accessible
38 * by the owning thread.
39 */
40 struct ike_sa_manager_t {
41
42 /**
43 * Checkout an existing IKE_SA.
44 *
45 * @param ike_sa_id the SA identifier, will be updated
46 * @returns
47 * - checked out IKE_SA if found
48 * - NULL, if specified IKE_SA is not found.
49 */
50 ike_sa_t* (*checkout) (ike_sa_manager_t* this, ike_sa_id_t *sa_id);
51
52 /**
53 * Create and check out a new IKE_SA.
54 *
55 * @param version IKE version of this SA
56 * @param initiator TRUE for initiator, FALSE otherwise
57 * @returns created and checked out IKE_SA
58 */
59 ike_sa_t* (*checkout_new) (ike_sa_manager_t* this, ike_version_t version,
60 bool initiator);
61
62 /**
63 * Checkout an IKE_SA by a message.
64 *
65 * In some situations, it is necessary that the manager knows the
66 * message to use for the checkout. This has the following reasons:
67 *
68 * 1. If the targeted IKE_SA is already processing a message, we do not
69 * check it out if the message ID is the same.
70 * 2. If it is an IKE_SA_INIT request, we have to check if it is a
71 * retransmission. If so, we have to drop the message, we would
72 * create another unneeded IKE_SA for each retransmitted packet.
73 *
74 * A call to checkout_by_message() returns a (maybe new created) IKE_SA.
75 * If processing the message does not make sense (for the reasons above),
76 * NULL is returned.
77 *
78 * @param ike_sa_id the SA identifier, will be updated
79 * @returns
80 * - checked out/created IKE_SA
81 * - NULL to not process message further
82 */
83 ike_sa_t* (*checkout_by_message) (ike_sa_manager_t* this, message_t *message);
84
85 /**
86 * Checkout an IKE_SA for initiation by a peer_config.
87 *
88 * To initiate, a CHILD_SA may be established within an existing IKE_SA.
89 * This call checks for an existing IKE_SA by comparing the configuration.
90 * If the CHILD_SA can be created in an existing IKE_SA, the matching SA
91 * is returned.
92 * If no IKE_SA is found, a new one is created. This is also the case when
93 * the found IKE_SA is in the DELETING state.
94 *
95 * @param peer_cfg configuration used to find an existing IKE_SA
96 * @return checked out/created IKE_SA
97 */
98 ike_sa_t* (*checkout_by_config) (ike_sa_manager_t* this,
99 peer_cfg_t *peer_cfg);
100
101 /**
102 * Check for duplicates of the given IKE_SA.
103 *
104 * Measures are taken according to the uniqueness policy of the IKE_SA.
105 * The return value indicates whether duplicates have been found and if
106 * further measures should be taken (e.g. cancelling an IKE_AUTH exchange).
107 * check_uniqueness() must be called before the IKE_SA is complete,
108 * deadlocks occur otherwise.
109 *
110 * @param ike_sa ike_sa to check
111 * @param force_replace replace existing SAs, regardless of unique policy
112 * @return TRUE, if the given IKE_SA has duplicates and
113 * should be deleted
114 */
115 bool (*check_uniqueness)(ike_sa_manager_t *this, ike_sa_t *ike_sa,
116 bool force_replace);
117
118 /**
119 * Check if we already have a connected IKE_SA between two identities.
120 *
121 * @param me own identity
122 * @param other remote identity
123 * @param family address family to include in uniqueness check
124 * @return TRUE if we have a connected IKE_SA
125 */
126 bool (*has_contact)(ike_sa_manager_t *this, identification_t *me,
127 identification_t *other, int family);
128
129 /**
130 * Check out an IKE_SA a unique ID.
131 *
132 * Every IKE_SA is uniquely identified by a numerical ID. This checkout
133 * function uses the unique ID of the IKE_SA to check it out.
134 *
135 * @param id unique ID of the object
136 * @return
137 * - checked out IKE_SA, if found
138 * - NULL, if not found
139 */
140 ike_sa_t* (*checkout_by_id) (ike_sa_manager_t* this, u_int32_t id);
141
142 /**
143 * Check out an IKE_SA by the policy/connection name.
144 *
145 * Check out the IKE_SA by the configuration name, either from the IKE- or
146 * one of its CHILD_SAs.
147 *
148 * @param name name of the connection/policy
149 * @param child TRUE to use policy name, FALSE to use conn name
150 * @return
151 * - checked out IKE_SA, if found
152 * - NULL, if not found
153 */
154 ike_sa_t* (*checkout_by_name) (ike_sa_manager_t* this, char *name,
155 bool child);
156
157 /**
158 * Create an enumerator over all stored IKE_SAs.
159 *
160 * While enumerating an IKE_SA, it is temporarily checked out and
161 * automatically checked in after the current enumeration step.
162 *
163 * @param wait TRUE to wait for checked out SAs, FALSE to skip
164 * @return enumerator over all IKE_SAs.
165 */
166 enumerator_t *(*create_enumerator) (ike_sa_manager_t* this, bool wait);
167
168 /**
169 * Create an enumerator over ike_sa_id_t*, matching peer identities.
170 *
171 * The remote peer is identified by its XAuth or EAP identity, if available.
172 *
173 * @param me local peer identity to match
174 * @param other remote peer identity to match
175 * @param family address family to match, 0 for any
176 * @return enumerator over ike_sa_id_t*
177 */
178 enumerator_t* (*create_id_enumerator)(ike_sa_manager_t *this,
179 identification_t *me, identification_t *other,
180 int family);
181
182 /**
183 * Checkin the SA after usage.
184 *
185 * If the IKE_SA is not registered in the manager, a new entry is created.
186 *
187 * @param ike_sa_id the SA identifier, will be updated
188 * @param ike_sa checked out SA
189 */
190 void (*checkin) (ike_sa_manager_t* this, ike_sa_t *ike_sa);
191
192 /**
193 * Destroy a checked out SA.
194 *
195 * The IKE SA is destroyed without notification of the remote peer.
196 * Use this only if the other peer doesn't respond or behaves not
197 * as predicted.
198 * Checking in and destruction is an atomic operation (for the IKE_SA),
199 * so this can be called if the SA is in a "unclean" state, without the
200 * risk that another thread can get the SA.
201 *
202 * @param ike_sa SA to delete
203 */
204 void (*checkin_and_destroy) (ike_sa_manager_t* this, ike_sa_t *ike_sa);
205
206 /**
207 * Get the number of IKE_SAs currently registered.
208 *
209 * @return number of registered IKE_SAs
210 */
211 u_int (*get_count)(ike_sa_manager_t *this);
212
213 /**
214 * Get the number of IKE_SAs which are in the connecting state.
215 *
216 * To prevent the server from resource exhaustion, cookies and other
217 * mechanisms are used. The number of half open IKE_SAs is a good
218 * indicator to see if a peer is flooding the server.
219 * If a host is supplied, only the number of half open IKE_SAs initiated
220 * from this IP are counted.
221 * Only SAs for which we are the responder are counted.
222 *
223 * @param ip NULL for all, IP for half open IKE_SAs with IP
224 * @return number of half open IKE_SAs
225 */
226 u_int (*get_half_open_count) (ike_sa_manager_t *this, host_t *ip);
227
228 /**
229 * Delete all existing IKE_SAs and destroy them immediately.
230 *
231 * Threads will be driven out, so all SAs can be deleted cleanly.
232 * To a flush(), an immediate call to destroy() is mandatory; no other
233 * method may be used.
234 */
235 void (*flush)(ike_sa_manager_t *this);
236
237 /**
238 * Destroys the manager with all associated SAs.
239 *
240 * A call to flush() is required before calling destroy.
241 */
242 void (*destroy) (ike_sa_manager_t *this);
243 };
244
245 /**
246 * Create the IKE_SA manager.
247 *
248 * @returns ike_sa_manager_t object, NULL if initialization fails
249 */
250 ike_sa_manager_t *ike_sa_manager_create(void);
251
252 #endif /** IKE_SA_MANAGER_H_ @}*/