Implemented limited payload parsing for IKEv1 SA payloads
[strongswan.git] / src / libcharon / encoding / payloads / transform_attribute.c
1 /*
2 * Copyright (C) 2005-2010 Martin Willi
3 * Copyright (C) 2010 revosec AG
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 #include <string.h>
19 #include <stddef.h>
20
21 #include "transform_attribute.h"
22
23 #include <encoding/payloads/encodings.h>
24 #include <library.h>
25
26 ENUM(tattr_ph1_names, TATTR_PH1_ENCRYPTION_ALGORITHM, TATTR_PH1_GROUP_ORDER,
27 "ENCRYPTION_ALGORITHM",
28 "HASH_ALGORITHM",
29 "AUTH_METHOD",
30 "GROUP",
31 "GROUP_TYPE",
32 "GROUP_PRIME",
33 "GROUP_GENONE",
34 "GROUP_GENTWO",
35 "GROUP_CURVE_A",
36 "GROUP_CURVE_B",
37 "LIFE_TYPE",
38 "LIFE_DURATION",
39 "PRF",
40 "KEY_LENGTH",
41 "FIELD_SIZE",
42 "GROUP_ORDER",
43 );
44
45 ENUM(tattr_ph2_names, TATTR_PH2_SA_LIFE_TYPE, TATTR_PH2_EXT_SEQ_NUMBER,
46 "SA_LIFE_TYPE",
47 "SA_LIFE_DURATION",
48 "GROUP",
49 "ENCAP_MODE",
50 "AUTH_ALGORITHM",
51 "KEY_LENGTH",
52 "KEY_ROUNDS",
53 "COMP_DICT_SIZE",
54 "COMP_PRIV_ALGORITHM",
55 "ECN_TUNNEL",
56 "EXT_SEQ_NUMBER",
57 );
58
59 ENUM(tattr_ikev2_names, TATTR_IKEV2_KEY_LENGTH, TATTR_IKEV2_KEY_LENGTH,
60 "KEY_LENGTH",
61 );
62
63
64 typedef struct private_transform_attribute_t private_transform_attribute_t;
65
66 /**
67 * Private data of an transform_attribute_t object.
68 */
69 struct private_transform_attribute_t {
70
71 /**
72 * Public transform_attribute_t interface.
73 */
74 transform_attribute_t public;
75
76 /**
77 * Attribute Format Flag.
78 *
79 * - TRUE means value is stored in attribute_length_or_value
80 * - FALSE means value is stored in attribute_value
81 */
82 bool attribute_format;
83
84 /**
85 * Type of the attribute.
86 */
87 u_int16_t attribute_type;
88
89 /**
90 * Attribute Length if attribute_format is 0, attribute Value otherwise.
91 */
92 u_int16_t attribute_length_or_value;
93
94 /**
95 * Attribute value as chunk if attribute_format is 0 (FALSE).
96 */
97 chunk_t attribute_value;
98
99 /**
100 * Payload type, TRANSFORM_ATTRIBUTE or TRANSFORM_ATTRIBUTE_V1
101 */
102 payload_type_t type;
103 };
104
105 /**
106 * Encoding rules for IKEv1/IKEv2 transform attributes
107 */
108 static encoding_rule_t encodings[] = {
109 /* Flag defining the format of this payload */
110 { ATTRIBUTE_FORMAT, offsetof(private_transform_attribute_t, attribute_format) },
111 /* type of the attribute as 15 bit unsigned integer */
112 { ATTRIBUTE_TYPE, offsetof(private_transform_attribute_t, attribute_type) },
113 /* Length or value, depending on the attribute format flag */
114 { ATTRIBUTE_LENGTH_OR_VALUE,offsetof(private_transform_attribute_t, attribute_length_or_value) },
115 /* Value of attribute if attribute format flag is zero */
116 { ATTRIBUTE_VALUE, offsetof(private_transform_attribute_t, attribute_value) }
117 };
118
119 /*
120 1 2 3
121 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
122 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
123 !A! Attribute Type ! AF=0 Attribute Length !
124 !F! ! AF=1 Attribute Value !
125 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
126 ! AF=0 Attribute Value !
127 ! AF=1 Not Transmitted !
128 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
129 */
130
131 METHOD(payload_t, verify, status_t,
132 private_transform_attribute_t *this)
133 {
134 return SUCCESS;
135 }
136
137 METHOD(payload_t, get_encoding_rules, void,
138 private_transform_attribute_t *this, encoding_rule_t **rules,
139 size_t *rule_count)
140 {
141 *rules = encodings;
142 *rule_count = countof(encodings);
143 }
144
145 METHOD(payload_t, get_type, payload_type_t,
146 private_transform_attribute_t *this)
147 {
148 return this->type;
149 }
150
151 METHOD(payload_t, get_next_type, payload_type_t,
152 private_transform_attribute_t *this)
153 {
154 return NO_PAYLOAD;
155 }
156
157 METHOD(payload_t, set_next_type, void,
158 private_transform_attribute_t *this, payload_type_t type)
159 {
160 }
161
162 METHOD(payload_t, get_length, size_t,
163 private_transform_attribute_t *this)
164 {
165 if (this->attribute_format)
166 {
167 return 4;
168 }
169 return this->attribute_length_or_value + 4;
170 }
171
172 METHOD(transform_attribute_t, set_value_chunk, void,
173 private_transform_attribute_t *this, chunk_t value)
174 {
175 chunk_free(&this->attribute_value);
176
177 if (value.len != 2)
178 {
179 this->attribute_value = chunk_clone(value);
180 this->attribute_length_or_value = value.len;
181 this->attribute_format = FALSE;
182 }
183 else
184 {
185 memcpy(&this->attribute_length_or_value, value.ptr, value.len);
186 }
187 }
188
189 METHOD(transform_attribute_t, set_value, void,
190 private_transform_attribute_t *this, u_int16_t value)
191 {
192 chunk_free(&this->attribute_value);
193 this->attribute_length_or_value = value;
194 this->attribute_format = TRUE;
195 }
196
197 METHOD(transform_attribute_t, get_value_chunk, chunk_t,
198 private_transform_attribute_t *this)
199 {
200 if (this->attribute_format)
201 {
202 return chunk_from_thing(this->attribute_length_or_value);
203 }
204 return this->attribute_value;
205 }
206
207 METHOD(transform_attribute_t, get_value, u_int16_t,
208 private_transform_attribute_t *this)
209 {
210 return this->attribute_length_or_value;
211 }
212
213 METHOD(transform_attribute_t, set_attribute_type, void,
214 private_transform_attribute_t *this, u_int16_t type)
215 {
216 this->attribute_type = type & 0x7FFF;
217 }
218
219 METHOD(transform_attribute_t, get_attribute_type, u_int16_t,
220 private_transform_attribute_t *this)
221 {
222 return this->attribute_type;
223 }
224
225 METHOD(transform_attribute_t, clone_, transform_attribute_t*,
226 private_transform_attribute_t *this)
227 {
228 private_transform_attribute_t *new;
229
230 new = (private_transform_attribute_t*)transform_attribute_create(this->type);
231
232 new->attribute_format = this->attribute_format;
233 new->attribute_type = this->attribute_type;
234 new->attribute_length_or_value = this->attribute_length_or_value;
235
236 if (!new->attribute_format)
237 {
238 new->attribute_value = chunk_clone(this->attribute_value);
239 }
240 return &new->public;
241 }
242
243 METHOD2(payload_t, transform_attribute_t, destroy, void,
244 private_transform_attribute_t *this)
245 {
246 free(this->attribute_value.ptr);
247 free(this);
248 }
249
250 /*
251 * Described in header.
252 */
253 transform_attribute_t *transform_attribute_create(payload_type_t type)
254 {
255 private_transform_attribute_t *this;
256
257 INIT(this,
258 .public = {
259 .payload_interface = {
260 .verify = _verify,
261 .get_encoding_rules = _get_encoding_rules,
262 .get_length = _get_length,
263 .get_next_type = _get_next_type,
264 .set_next_type = _set_next_type,
265 .get_type = _get_type,
266 .destroy = _destroy,
267 },
268 .set_value_chunk = _set_value_chunk,
269 .set_value = _set_value,
270 .get_value_chunk = _get_value_chunk,
271 .get_value = _get_value,
272 .set_attribute_type = _set_attribute_type,
273 .get_attribute_type = _get_attribute_type,
274 .clone = _clone_,
275 .destroy = _destroy,
276 },
277 .attribute_format = TRUE,
278 .type = type,
279 );
280 return &this->public;
281 }
282
283 /*
284 * Described in header.
285 */
286 transform_attribute_t *transform_attribute_create_key_length(u_int16_t key_length)
287 {
288 transform_attribute_t *attribute;
289
290 attribute = transform_attribute_create(TRANSFORM_ATTRIBUTE);
291 attribute->set_attribute_type(attribute, TATTR_IKEV2_KEY_LENGTH);
292 attribute->set_value(attribute, key_length);
293
294 return attribute;
295 }