- added verify function to all payload types
[strongswan.git] / Source / charon / payloads / transform_attribute.c
1 /**
2 * @file transform_attribute.c
3 *
4 * @brief Declaration of the class transform_attribute_t.
5 *
6 * An object of this type represents an IKEv2 TRANSFORM attribute.
7 *
8 */
9
10 /*
11 * Copyright (C) 2005 Jan Hutter, Martin Willi
12 * Hochschule fuer Technik Rapperswil
13 *
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU General Public License as published by the
16 * Free Software Foundation; either version 2 of the License, or (at your
17 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
18 *
19 * This program is distributed in the hope that it will be useful, but
20 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
21 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 * for more details.
23 */
24
25 /* offsetof macro */
26 #include <stddef.h>
27
28 #include "transform_attribute.h"
29
30 #include "encodings.h"
31 #include "../types.h"
32 #include "../utils/allocator.h"
33
34 /**
35 * Private data of an transform_attribute_t Object
36 *
37 */
38 typedef struct private_transform_attribute_s private_transform_attribute_t;
39
40 struct private_transform_attribute_s {
41 /**
42 * public transform_attribute_t interface
43 */
44 transform_attribute_t public;
45
46 /**
47 * Attribute Format Flag
48 *
49 * - TRUE means value is stored in attribute_length_or_value
50 * - FALSE means value is stored in attribute_value
51 */
52 bool attribute_format;
53
54 /**
55 * Type of the attribute
56 */
57 u_int16_t attribute_type;
58
59 /**
60 * Attribute Length if attribute_format is 0, attribute Value otherwise
61 */
62 u_int16_t attribute_length_or_value;
63
64 /**
65 * Attribute value as chunk if attribute_format is 0 (FALSE)
66 */
67 chunk_t attribute_value;
68 };
69
70
71
72 /**
73 * string mappings for transform_attribute_type_t
74 */
75 mapping_t transform_attribute_type_m[] = {
76 {ATTRIBUTE_UNDEFINED, "ATTRIBUTE_UNDEFINED"},
77 {KEY_LENGTH, "KEY_LENGTH"},
78 {MAPPING_END, NULL}
79 };
80
81 /**
82 * Encoding rules to parse or generate a Transform attribute
83 *
84 * The defined offsets are the positions in a object of type
85 * private_transform_attribute_t.
86 *
87 */
88 encoding_rule_t transform_attribute_encodings[] = {
89 /* Flag defining the format of this payload */
90 { ATTRIBUTE_FORMAT, offsetof(private_transform_attribute_t, attribute_format) },
91 /* type of the attribute as 15 bit unsigned integer */
92 { ATTRIBUTE_TYPE, offsetof(private_transform_attribute_t, attribute_type) },
93 /* Length or value, depending on the attribute format flag */
94 { ATTRIBUTE_LENGTH_OR_VALUE, offsetof(private_transform_attribute_t, attribute_length_or_value) },
95 /* Value of attribute if attribute format flag is zero */
96 { ATTRIBUTE_VALUE, offsetof(private_transform_attribute_t, attribute_value) }
97 };
98
99 /*
100 1 2 3
101 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
102 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
103 !A! Attribute Type ! AF=0 Attribute Length !
104 !F! ! AF=1 Attribute Value !
105 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
106 ! AF=0 Attribute Value !
107 ! AF=1 Not Transmitted !
108 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
109 */
110
111 /**
112 * Implements payload_t's verify function.
113 * See #payload_s.verify for description.
114 */
115 static status_t verify(private_transform_attribute_t *this)
116 {
117 if (this->attribute_type != KEY_LENGTH)
118 {
119 return FAILED;
120 }
121
122 return SUCCESS;
123 }
124
125 /**
126 * Implements payload_t's and transform_attribute_t's destroy function.
127 * See #payload_s.destroy or transform_attribute_s.destroy for description.
128 */
129 static status_t destroy(private_transform_attribute_t *this)
130 {
131 if (this->attribute_value.ptr != NULL)
132 {
133 allocator_free(this->attribute_value.ptr);
134 }
135 allocator_free(this);
136
137 return SUCCESS;
138 }
139
140 /**
141 * Implements payload_t's get_encoding_rules function.
142 * See #payload_s.get_encoding_rules for description.
143 */
144 static status_t get_encoding_rules(private_transform_attribute_t *this, encoding_rule_t **rules, size_t *rule_count)
145 {
146 *rules = transform_attribute_encodings;
147 *rule_count = sizeof(transform_attribute_encodings) / sizeof(encoding_rule_t);
148
149 return SUCCESS;
150 }
151
152 /**
153 * Implements payload_t's get_type function.
154 * See #payload_s.get_type for description.
155 */
156 static payload_type_t get_type(private_transform_attribute_t *this)
157 {
158 return TRANSFORM_ATTRIBUTE;
159 }
160
161 /**
162 * Implements payload_t's get_next_type function.
163 * See #payload_s.get_next_type for description.
164 */
165 static payload_type_t get_next_type(private_transform_attribute_t *this)
166 {
167 return (NO_PAYLOAD);
168 }
169
170 /**
171 * Implements payload_t's set_next_type function.
172 * See #payload_s.set_next_type for description.
173 */
174 static status_t set_next_type(private_transform_attribute_t *this,payload_type_t type)
175 {
176 return SUCCESS;
177 }
178
179 /**
180 * Implements payload_t's get_length function.
181 * See #payload_s.get_length for description.
182 */
183 static size_t get_length(private_transform_attribute_t *this)
184 {
185 if (this->attribute_format == TRUE)
186 {
187 /*Attribute size is only 4 byte */
188 return 4;
189 }
190 return (this->attribute_length_or_value + 4);
191 }
192 /**
193 * Implements transform_attribute_t's set_value function.
194 * See #transform_attribute_s.set_value for description.
195 */
196 static status_t set_value_chunk(private_transform_attribute_t *this, chunk_t value)
197 {
198 if (this->attribute_value.ptr != NULL)
199 {
200 /* free existing value */
201 allocator_free(this->attribute_value.ptr);
202 this->attribute_value.ptr = NULL;
203 this->attribute_value.len = 0;
204
205 }
206
207 if (value.len > 2)
208 {
209 this->attribute_value.ptr = allocator_clone_bytes(value.ptr,value.len);
210 if (this->attribute_value.ptr == NULL)
211 {
212 return OUT_OF_RES;
213 }
214 this->attribute_value.len = value.len;
215 this->attribute_length_or_value = value.len;
216 /* attribute has not a fixed length */
217 this->attribute_format = FALSE;
218 }
219 else
220 {
221 memcpy(&(this->attribute_length_or_value),value.ptr,value.len);
222 }
223 return SUCCESS;
224 }
225
226 /**
227 * Implements transform_attribute_t's set_value function.
228 * See #transform_attribute_s.set_value for description.
229 */
230 static status_t set_value(private_transform_attribute_t *this, u_int16_t value)
231 {
232 if (this->attribute_value.ptr != NULL)
233 {
234 /* free existing value */
235 allocator_free(this->attribute_value.ptr);
236 this->attribute_value.ptr = NULL;
237 this->attribute_value.len = 0;
238
239 }
240 this->attribute_length_or_value = value;
241 return SUCCESS;
242 }
243
244 /**
245 * Implements transform_attribute_t's get_value_chunk function.
246 * See #transform_attribute_s.get_value_chunk for description.
247 */
248 static chunk_t get_value_chunk (private_transform_attribute_t *this)
249 {
250 chunk_t value;
251
252 if (this->attribute_format == FALSE)
253 {
254 value.ptr = this->attribute_value.ptr;
255 value.len = this->attribute_value.len;
256 }
257 else
258 {
259 value.ptr = (void *) &(this->attribute_length_or_value);
260 value.len = 2;
261 }
262
263 return value;
264 }
265
266 /**
267 * Implements transform_attribute_t's get_value function.
268 * See #transform_attribute_s.get_value for description.
269 */
270 static u_int16_t get_value (private_transform_attribute_t *this)
271 {
272 return this->attribute_length_or_value;
273 }
274
275
276 /**
277 * Implements transform_attribute_t's set_attribute_type function.
278 * See #transform_attribute_s.set_attribute_type for description.
279 */
280 static status_t set_attribute_type (private_transform_attribute_t *this, u_int16_t type)
281 {
282 this->attribute_type = type & 0x7FFF;
283 return SUCCESS;
284 }
285
286 /**
287 * Implements transform_attribute_t's get_attribute_type function.
288 * See #transform_attribute_s.get_attribute_type for description.
289 */
290 static u_int16_t get_attribute_type (private_transform_attribute_t *this)
291 {
292 return this->attribute_type;
293 }
294
295 /*
296 * Described in header
297 */
298 transform_attribute_t *transform_attribute_create()
299 {
300 private_transform_attribute_t *this = allocator_alloc_thing(private_transform_attribute_t);
301 if (this == NULL)
302 {
303 return NULL;
304 }
305
306 /* payload interface */
307 this->public.payload_interface.verify = (status_t (*) (payload_t *))verify;
308 this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
309 this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
310 this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
311 this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
312 this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
313 this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
314
315 /* public functions */
316 this->public.set_value_chunk = (status_t (*) (transform_attribute_t *,chunk_t)) set_value_chunk;
317 this->public.set_value = (status_t (*) (transform_attribute_t *,u_int16_t)) set_value;
318 this->public.get_value_chunk = (chunk_t (*) (transform_attribute_t *)) get_value_chunk;
319 this->public.get_value = (u_int16_t (*) (transform_attribute_t *)) get_value;
320 this->public.set_attribute_type = (status_t (*) (transform_attribute_t *,u_int16_t type)) set_attribute_type;
321 this->public.get_attribute_type = (u_int16_t (*) (transform_attribute_t *)) get_attribute_type;
322 this->public.destroy = (status_t (*) (transform_attribute_t *)) destroy;
323
324 /* set default values of the fields */
325 this->attribute_format = TRUE;
326 this->attribute_type = 0;
327 this->attribute_length_or_value = 0;
328 this->attribute_value.ptr = NULL;
329 this->attribute_value.len = 0;
330
331 return (&(this->public));
332 }
333