- refactored ike proposal
[strongswan.git] / Source / charon / encoding / payloads / sa_payload.c
1 /**
2 * @file sa_payload.c
3 *
4 * @brief Implementation of sa_payload_t.
5 *
6 */
7
8 /*
9 * Copyright (C) 2005 Jan Hutter, 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 /* offsetof macro */
24 #include <stddef.h>
25
26 #include "sa_payload.h"
27
28 #include <encoding/payloads/encodings.h>
29 #include <utils/allocator.h>
30 #include <utils/linked_list.h>
31
32
33 typedef struct private_sa_payload_t private_sa_payload_t;
34
35 /**
36 * Private data of an sa_payload_t object.
37 *
38 */
39 struct private_sa_payload_t {
40 /**
41 * Public sa_payload_t interface.
42 */
43 sa_payload_t public;
44
45 /**
46 * Next payload type.
47 */
48 u_int8_t next_payload;
49
50 /**
51 * Critical flag.
52 */
53 bool critical;
54
55 /**
56 * Length of this payload.
57 */
58 u_int16_t payload_length;
59
60 /**
61 * Proposals in this payload are stored in a linked_list_t.
62 */
63 linked_list_t * proposals;
64
65 /**
66 * @brief Computes the length of this payload.
67 *
68 * @param this calling private_sa_payload_t object
69 */
70 void (*compute_length) (private_sa_payload_t *this);
71 };
72
73 /**
74 * Encoding rules to parse or generate a IKEv2-SA Payload
75 *
76 * The defined offsets are the positions in a object of type
77 * private_sa_payload_t.
78 *
79 */
80 encoding_rule_t sa_payload_encodings[] = {
81 /* 1 Byte next payload type, stored in the field next_payload */
82 { U_INT_8, offsetof(private_sa_payload_t, next_payload) },
83 /* the critical bit */
84 { FLAG, offsetof(private_sa_payload_t, critical) },
85 /* 7 Bit reserved bits, nowhere stored */
86 { RESERVED_BIT, 0 },
87 { RESERVED_BIT, 0 },
88 { RESERVED_BIT, 0 },
89 { RESERVED_BIT, 0 },
90 { RESERVED_BIT, 0 },
91 { RESERVED_BIT, 0 },
92 { RESERVED_BIT, 0 },
93 /* Length of the whole SA payload*/
94 { PAYLOAD_LENGTH, offsetof(private_sa_payload_t, payload_length) },
95 /* Proposals are stored in a proposal substructure,
96 offset points to a linked_list_t pointer */
97 { PROPOSALS, offsetof(private_sa_payload_t, proposals) }
98 };
99
100 /*
101 1 2 3
102 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
103 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
104 ! Next Payload !C! RESERVED ! Payload Length !
105 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
106 ! !
107 ~ <Proposals> ~
108 ! !
109 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
110 */
111
112 /**
113 * Implementation of payload_t.verify.
114 */
115 static status_t verify(private_sa_payload_t *this)
116 {
117 int proposal_number = 1;
118 status_t status = SUCCESS;
119 iterator_t *iterator;
120 bool first = TRUE;
121
122 if (this->critical)
123 {
124 /* critical bit set! */
125 return FAILED;
126 }
127
128 /* check proposal numbering */
129 iterator = this->proposals->create_iterator(this->proposals,TRUE);
130
131 while(iterator->has_next(iterator))
132 {
133 proposal_substructure_t *current_proposal;
134 iterator->current(iterator,(void **)&current_proposal);
135 if (current_proposal->get_proposal_number(current_proposal) > proposal_number)
136 {
137 if (first)
138 {
139 /* first number must be 1 */
140 status = FAILED;
141 break;
142 }
143
144 if (current_proposal->get_proposal_number(current_proposal) != (proposal_number + 1))
145 {
146 /* must be only one more then previous proposal */
147 status = FAILED;
148 break;
149 }
150 }
151 else if (current_proposal->get_proposal_number(current_proposal) < proposal_number)
152 {
153 /* must not be smaller then proceeding one */
154 status = FAILED;
155 break;
156 }
157
158 status = current_proposal->payload_interface.verify(&(current_proposal->payload_interface));
159 if (status != SUCCESS)
160 {
161 break;
162 }
163 first = FALSE;
164 }
165
166 iterator->destroy(iterator);
167 return status;
168 }
169
170
171 /**
172 * Implementation of payload_t.destroy and sa_payload_t.destroy.
173 */
174 static status_t destroy(private_sa_payload_t *this)
175 {
176 /* all proposals are getting destroyed */
177 while (this->proposals->get_count(this->proposals) > 0)
178 {
179 proposal_substructure_t *current_proposal;
180 this->proposals->remove_last(this->proposals,(void **)&current_proposal);
181 current_proposal->destroy(current_proposal);
182 }
183 this->proposals->destroy(this->proposals);
184
185 allocator_free(this);
186
187 return SUCCESS;
188 }
189
190 /**
191 * Implementation of payload_t.get_encoding_rules.
192 */
193 static void get_encoding_rules(private_sa_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
194 {
195 *rules = sa_payload_encodings;
196 *rule_count = sizeof(sa_payload_encodings) / sizeof(encoding_rule_t);
197 }
198
199 /**
200 * Implementation of payload_t.get_type.
201 */
202 static payload_type_t get_type(private_sa_payload_t *this)
203 {
204 return SECURITY_ASSOCIATION;
205 }
206
207 /**
208 * Implementation of payload_t.get_next_type.
209 */
210 static payload_type_t get_next_type(private_sa_payload_t *this)
211 {
212 return (this->next_payload);
213 }
214
215 /**
216 * Implementation of payload_t.set_next_type.
217 */
218 static void set_next_type(private_sa_payload_t *this,payload_type_t type)
219 {
220 this->next_payload = type;
221 }
222
223 /**
224 * Implementation of payload_t.get_length.
225 */
226 static size_t get_length(private_sa_payload_t *this)
227 {
228 this->compute_length(this);
229 return this->payload_length;
230 }
231
232 /**
233 * Implementation of sa_payload_t.create_proposal_substructure_iterator.
234 */
235 static iterator_t *create_proposal_substructure_iterator (private_sa_payload_t *this,bool forward)
236 {
237 return this->proposals->create_iterator(this->proposals,forward);
238 }
239
240 /**
241 * Implementation of sa_payload_t.add_proposal_substructure.
242 */
243 static void add_proposal_substructure (private_sa_payload_t *this,proposal_substructure_t *proposal)
244 {
245 status_t status;
246 if (this->proposals->get_count(this->proposals) > 0)
247 {
248 proposal_substructure_t *last_proposal;
249 status = this->proposals->get_last(this->proposals,(void **) &last_proposal);
250 /* last transform is now not anymore last one */
251 last_proposal->set_is_last_proposal(last_proposal,FALSE);
252 }
253 proposal->set_is_last_proposal(proposal,TRUE);
254
255 this->proposals->insert_last(this->proposals,(void *) proposal);
256 this->compute_length(this);
257 }
258
259 /**
260 * Implementation of sa_payload_t.add_proposal.
261 */
262 static void add_proposal(private_sa_payload_t *this, proposal_t *proposal)
263 {
264 proposal_substructure_t *substructure;
265 protocol_id_t proto[2];
266 u_int i;
267
268 /* build the substructures for every protocol */
269 proposal->get_protocols(proposal, proto);
270 for (i = 0; i<2; i++)
271 {
272 if (proto[i] != UNDEFINED_PROTOCOL_ID)
273 {
274 substructure = proposal_substructure_create_from_proposal(proposal, proto[i]);
275 add_proposal_substructure(this, substructure);
276 }
277 }
278 }
279
280 /**
281 * Implementation of sa_payload_t.get_proposals.
282 */
283 static linked_list_t *get_proposals(private_sa_payload_t *this)
284 {
285 int proposal_struct_number = 0;
286 iterator_t *iterator;
287 proposal_t *proposal;
288 linked_list_t *proposal_list;
289
290 /* this list will hold our proposals */
291 proposal_list = linked_list_create();
292
293 /* iterate over structures, one OR MORE structures will result in a proposal */
294 iterator = this->proposals->create_iterator(this->proposals,TRUE);
295 while (iterator->has_next(iterator))
296 {
297 proposal_substructure_t *proposal_struct;
298 iterator->current(iterator,(void **)&(proposal_struct));
299
300 if (proposal_struct->get_proposal_number(proposal_struct) > proposal_struct_number)
301 {
302 /* here starts a new proposal, create a new one and add it to the list */
303 proposal_struct_number = proposal_struct->get_proposal_number(proposal_struct);
304 proposal = proposal_create(proposal_struct_number);
305 proposal_list->insert_last(proposal_list, proposal);
306 }
307 /* proposal_substructure_t does the dirty work and builds up the proposal */
308 proposal_struct->add_to_proposal(proposal_struct, proposal);
309 }
310 iterator->destroy(iterator);
311 return proposal_list;
312 }
313
314 /**
315 * Implementation of private_sa_payload_t.compute_length.
316 */
317 static void compute_length (private_sa_payload_t *this)
318 {
319 iterator_t *iterator;
320 size_t length = SA_PAYLOAD_HEADER_LENGTH;
321 iterator = this->proposals->create_iterator(this->proposals,TRUE);
322 while (iterator->has_next(iterator))
323 {
324 payload_t *current_proposal;
325 iterator->current(iterator,(void **) &current_proposal);
326 length += current_proposal->get_length(current_proposal);
327 }
328 iterator->destroy(iterator);
329
330 this->payload_length = length;
331 }
332
333 /*
334 * Described in header.
335 */
336 sa_payload_t *sa_payload_create()
337 {
338 private_sa_payload_t *this = allocator_alloc_thing(private_sa_payload_t);
339
340 /* public interface */
341 this->public.payload_interface.verify = (status_t (*) (payload_t *))verify;
342 this->public.payload_interface.get_encoding_rules = (void (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
343 this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
344 this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
345 this->public.payload_interface.set_next_type = (void (*) (payload_t *,payload_type_t)) set_next_type;
346 this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
347 this->public.payload_interface.destroy = (void (*) (payload_t *))destroy;
348
349 /* public functions */
350 this->public.create_proposal_substructure_iterator = (iterator_t* (*) (sa_payload_t *,bool)) create_proposal_substructure_iterator;
351 this->public.add_proposal_substructure = (void (*) (sa_payload_t *,proposal_substructure_t *)) add_proposal_substructure;
352 this->public.get_proposals = (linked_list_t* (*) (sa_payload_t *)) get_proposals;
353 this->public.destroy = (void (*) (sa_payload_t *)) destroy;
354
355 /* private functions */
356 this->compute_length = compute_length;
357
358 /* set default values of the fields */
359 this->critical = SA_PAYLOAD_CRITICAL_FLAG;
360 this->next_payload = NO_PAYLOAD;
361 this->payload_length = SA_PAYLOAD_HEADER_LENGTH;
362
363 this->proposals = linked_list_create();
364 return (&(this->public));
365 }
366
367 /*
368 * Described in header.
369 */
370 sa_payload_t *sa_payload_create_from_proposal_list(linked_list_t *proposals)
371 {
372 iterator_t *iterator;
373 proposal_t *proposal;
374 sa_payload_t *sa_payload = sa_payload_create();
375
376 /* add every payload from the list */
377 iterator = proposals->create_iterator(proposals, TRUE);
378 while (iterator->has_next(iterator))
379 {
380 iterator->current(iterator, (void**)&proposal);
381 add_proposal((private_sa_payload_t*)sa_payload, proposal);
382 }
383 iterator->destroy(iterator);
384
385 return sa_payload;
386 }
387
388 /*
389 * Described in header.
390 */
391 sa_payload_t *sa_payload_create_from_proposal(proposal_t *proposal)
392 {
393 sa_payload_t *sa_payload = sa_payload_create();
394
395 add_proposal((private_sa_payload_t*)sa_payload, proposal);
396
397 return sa_payload;
398 }