9d4f95401e49163ea2a0f0ac3a7bcadea5dc1bbe
[strongswan.git] / Source / charon / payloads / sa_payload.c
1 /**
2 * @file sa_payload.c
3 *
4 * @brief Declaration of the class sa_payload_t.
5 *
6 * An object of this type represents an IKEv2 SA-Payload and contains proposal
7 * substructures.
8 *
9 */
10
11 /*
12 * Copyright (C) 2005 Jan Hutter, Martin Willi
13 * Hochschule fuer Technik Rapperswil
14 *
15 * This program is free software; you can redistribute it and/or modify it
16 * under the terms of the GNU General Public License as published by the
17 * Free Software Foundation; either version 2 of the License, or (at your
18 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
19 *
20 * This program is distributed in the hope that it will be useful, but
21 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
22 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
23 * for more details.
24 */
25
26 /* offsetof macro */
27 #include <stddef.h>
28
29 #include "sa_payload.h"
30
31 #include "encodings.h"
32 #include "../utils/allocator.h"
33 #include "../utils/linked_list.h"
34
35
36 /**
37 * Private data of an sa_payload_t' Object
38 *
39 */
40 typedef struct private_sa_payload_s private_sa_payload_t;
41
42 struct private_sa_payload_s {
43 /**
44 * public sa_payload_t interface
45 */
46 sa_payload_t public;
47
48 /**
49 * next payload type
50 */
51 u_int8_t next_payload;
52
53 /**
54 * Critical flag
55 */
56 bool critical;
57
58 /**
59 * Length of this payload
60 */
61 u_int16_t payload_length;
62
63 /**
64 * Proposals in this payload are stored in a linked_list_t
65 */
66 linked_list_t * proposals;
67
68 /**
69 * @brief Computes the length of this payload.
70 *
71 * @param this calling private_sa_payload_t object
72 * @return
73 * SUCCESS in any case
74 */
75 status_t (*compute_length) (private_sa_payload_t *this);
76 };
77
78 /**
79 * Encoding rules to parse or generate a IKEv2-SA Payload
80 *
81 * The defined offsets are the positions in a object of type
82 * private_sa_payload_t.
83 *
84 */
85 encoding_rule_t sa_payload_encodings[] = {
86 /* 1 Byte next payload type, stored in the field next_payload */
87 { U_INT_8, offsetof(private_sa_payload_t, next_payload) },
88 /* the critical bit */
89 { FLAG, offsetof(private_sa_payload_t, critical) },
90 /* 7 Bit reserved bits, nowhere stored */
91 { RESERVED_BIT, 0 },
92 { RESERVED_BIT, 0 },
93 { RESERVED_BIT, 0 },
94 { RESERVED_BIT, 0 },
95 { RESERVED_BIT, 0 },
96 { RESERVED_BIT, 0 },
97 { RESERVED_BIT, 0 },
98 /* Length of the whole SA payload*/
99 { PAYLOAD_LENGTH, offsetof(private_sa_payload_t, payload_length) },
100 /* Proposals are stored in a proposal substructure,
101 offset points to a linked_list_t pointer */
102 { PROPOSALS, offsetof(private_sa_payload_t, proposals) }
103 };
104
105 /**
106 * Implements payload_t's and sa_payload_t's destroy function.
107 * See #payload_s.destroy or sa_payload_s.destroy for description.
108 */
109 static status_t destroy(private_sa_payload_t *this)
110 {
111 /* all proposals are getting destroyed */
112 while (this->proposals->get_count(this->proposals) > 0)
113 {
114 proposal_substructure_t *current_proposal;
115 if (this->proposals->remove_last(this->proposals,(void **)&current_proposal) != SUCCESS)
116 {
117 break;
118 }
119 current_proposal->destroy(current_proposal);
120 }
121 this->proposals->destroy(this->proposals);
122
123 allocator_free(this);
124
125 return SUCCESS;
126 }
127
128 /**
129 * Implements payload_t's get_encoding_rules function.
130 * See #payload_s.get_encoding_rules for description.
131 */
132 static status_t get_encoding_rules(private_sa_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
133 {
134 *rules = sa_payload_encodings;
135 *rule_count = sizeof(sa_payload_encodings) / sizeof(encoding_rule_t);
136
137 return SUCCESS;
138 }
139
140 /**
141 * Implements payload_t's get_type function.
142 * See #payload_s.get_type for description.
143 */
144 static payload_type_t get_type(private_sa_payload_t *this)
145 {
146 return SECURITY_ASSOCIATION;
147 }
148
149 /**
150 * Implements payload_t's get_next_type function.
151 * See #payload_s.get_next_type for description.
152 */
153 static payload_type_t get_next_type(private_sa_payload_t *this)
154 {
155 return (this->next_payload);
156 }
157
158 /**
159 * Implements payload_t's set_next_type function.
160 * See #payload_s.set_next_type for description.
161 */
162 static status_t set_next_type(private_sa_payload_t *this,payload_type_t type)
163 {
164 this->next_payload = type;
165 return SUCCESS;
166 }
167
168 /**
169 * Implements payload_t's get_length function.
170 * See #payload_s.get_length for description.
171 */
172 static size_t get_length(private_sa_payload_t *this)
173 {
174 this->compute_length(this);
175 return this->payload_length;
176 }
177
178 /**
179 * Implements sa_payload_t's create_proposal_substructure_iterator function.
180 * See #sa_payload_s.create_proposal_substructure_iterator for description.
181 */
182 static status_t create_proposal_substructure_iterator (private_sa_payload_t *this,linked_list_iterator_t **iterator,bool forward)
183 {
184 return (this->proposals->create_iterator(this->proposals,iterator,forward));
185 }
186
187 /**
188 * Implements sa_payload_t's add_proposal_substructure function.
189 * See #sa_payload_s.add_proposal_substructure for description.
190 */
191 static status_t add_proposal_substructure (private_sa_payload_t *this,proposal_substructure_t *proposal)
192 {
193 status_t status;
194 status = this->proposals->insert_last(this->proposals,(void *) proposal);
195 this->compute_length(this);
196 return status;
197 }
198
199 /**
200 * Implements private_sa_payload_t's compute_length function.
201 * See #private_sa_payload_s.compute_length for description.
202 */
203 static status_t compute_length (private_sa_payload_t *this)
204 {
205 linked_list_iterator_t *iterator;
206 status_t status;
207 size_t length = SA_PAYLOAD_HEADER_LENGTH;
208 status = this->proposals->create_iterator(this->proposals,&iterator,TRUE);
209 if (status != SUCCESS)
210 {
211 return length;
212 }
213 while (iterator->has_next(iterator))
214 {
215 payload_t *current_proposal;
216 iterator->current(iterator,(void **) &current_proposal);
217 length += current_proposal->get_length(current_proposal);
218 }
219 iterator->destroy(iterator);
220
221 this->payload_length = length;
222
223 return SUCCESS;
224 }
225
226 /*
227 * Described in header
228 */
229 sa_payload_t *sa_payload_create()
230 {
231 private_sa_payload_t *this = allocator_alloc_thing(private_sa_payload_t);
232 if (this == NULL)
233 {
234 return NULL;
235 }
236
237 this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
238 this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
239 this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
240 this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
241 this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
242 this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
243 this->public.create_proposal_substructure_iterator = (status_t (*) (sa_payload_t *,linked_list_iterator_t **,bool)) create_proposal_substructure_iterator;
244 this->public.add_proposal_substructure = (status_t (*) (sa_payload_t *,proposal_substructure_t *)) add_proposal_substructure;
245 this->public.destroy = (status_t (*) (sa_payload_t *)) destroy;
246
247 /* private functions */
248 this->compute_length = compute_length;
249
250 /* set default values of the fields */
251 this->critical = SA_PAYLOAD_CRITICAL_FLAG;
252 this->next_payload = NO_PAYLOAD;
253 this->payload_length = SA_PAYLOAD_HEADER_LENGTH;
254
255 this->proposals = linked_list_create();
256
257 if (this->proposals == NULL)
258 {
259 allocator_free(this);
260 return NULL;
261 }
262 return (&(this->public));
263 }
264
265