bb5224f260a90d695f72b60571905c6cde4ae8b0
[strongswan.git] / src / charon / sa / child_sa.h
1 /**
2 * @file child_sa.h
3 *
4 * @brief Interface of child_sa_t.
5 *
6 */
7
8 /*
9 * Copyright (C) 2005 Martin Willi
10 * Hochschule fuer Technik Rapperswil
11 *
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the
14 * Free Software Foundation; either version 2 of the License, or (at your
15 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
19 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 * for more details.
21 */
22
23
24 #ifndef CHILD_SA_H_
25 #define CHILD_SA_H_
26
27 #include <types.h>
28 #include <crypto/prf_plus.h>
29 #include <encoding/payloads/proposal_substructure.h>
30 #include <utils/logger.h>
31
32 typedef struct child_sa_t child_sa_t;
33
34 /**
35 * @brief Represents multiple IPsec SAs between two hosts.
36 *
37 * A child_sa_t contains multiple SAs. SAs for both
38 * directions are managed in one child_sa_t object, and
39 * if both AH and ESP is set up, both protocols are managed
40 * by one child_sa_t. This means we can have two or
41 * in the AH+ESP case four IPsec-SAs in one child_sa_t.
42 *
43 * The procedure for child sa setup is as follows:
44 * - A gets SPIs for a proposal via child_sa_t.alloc
45 * - A send the updated proposal to B
46 * - B selects a suitable proposal
47 * - B calls child_sa_t.add to add and update the selected proposal
48 * - B sends the updated proposal to A
49 * - A calls child_sa_t.update to update the already allocated SPIs with the chosen proposal
50 *
51 * Once SAs are set up, policies can be added using add_policies.
52 *
53 *
54 * @b Constructors:
55 * - child_sa_create()
56 *
57 * @ingroup sa
58 */
59 struct child_sa_t {
60
61 /**
62 * @brief Allocate SPIs for a given proposals.
63 *
64 * Since the kernel manages SPIs for us, we need
65 * to allocate them. If the proposal contains more
66 * than one protocol, for each protocol an SPI is
67 * allocated. SPIs are stored internally and written
68 * back to the proposal.
69 *
70 * @param this calling object
71 * @param proposal proposal for which SPIs are allocated
72 */
73 status_t (*alloc)(child_sa_t *this, linked_list_t* proposals);
74
75 /**
76 * @brief Install the kernel SAs for a proposal.
77 *
78 * Since the kernel manages SPIs for us, we need
79 * to allocate them. If the proposal contains more
80 * than one protocol, for each protocol an SPI is
81 * allocated. SPIs are stored internally and written
82 * back to the proposal.
83 *
84 * @param this calling object
85 * @param proposal proposal for which SPIs are allocated
86 * @param prf_plus key material to use for key derivation
87 */
88 status_t (*add)(child_sa_t *this, proposal_t *proposal, prf_plus_t *prf_plus);
89
90 /**
91 * @brief Install the kernel SAs for a proposal, if SPIs already allocated.
92 *
93 * This one updates the SAs in the kernel, which are
94 * allocated via alloc, with a selected proposals.
95 *
96 * @param this calling object
97 * @param proposal proposal for which SPIs are allocated
98 * @param prf_plus key material to use for key derivation
99 */
100 status_t (*update)(child_sa_t *this, proposal_t *proposal, prf_plus_t *prf_plus);
101
102 /**
103 * @brief Install the policies using some traffic selectors.
104 *
105 * Supplied lists of traffic_selector_t's specify the policies
106 * to use for this child sa.
107 *
108 * @param this calling object
109 * @param my_ts traffic selectors for local site
110 * @param other_ts traffic selectors for remote site
111 * @return SUCCESS or FAILED
112 */
113 status_t (*add_policies) (child_sa_t *this, linked_list_t *my_ts_list, linked_list_t *other_ts_list);
114
115 /**
116 * @brief Log the status of a child_sa to a logger.
117 *
118 * The status of ESP/AH SAs is logged with the supplied logger in
119 * a human readable form.
120 * Supplying NULL as logger uses the internal child_sa logger
121 * to do the logging. The name is only a log-prefix without further
122 * meaning.
123 *
124 * @param this calling object
125 * @param logger logger to use for logging
126 * @param name connection name
127 */
128 void (*log_status) (child_sa_t *this, logger_t *logger, char *name);
129
130 /**
131 * @brief Destroys a child_sa.
132 *
133 * @param this calling object
134 */
135 void (*destroy) (child_sa_t *this);
136 };
137
138 /**
139 * @brief Constructor to create a new child_sa_t.
140 *
141 * @param me own address
142 * @param other remote address
143 * @return child_sa_t object
144 *
145 * @ingroup sa
146 */
147 child_sa_t * child_sa_create(host_t *me, host_t *other);
148
149 #endif /*CHILD_SA_H_*/