use MAX_RADIUS_ATTRIBUTE_SIZE constant from radius_message header file
[strongswan.git] / src / libcharon / plugins / eap_ttls / eap_ttls_peer.c
1 /*
2 * Copyright (C) 2010 Andreas Steffen
3 * Copyright (C) 2010 HSR Hochschule fuer Technik Rapperswil
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * for more details.
14 */
15
16 #include "eap_ttls_peer.h"
17 #include "eap_ttls_avp.h"
18
19 #include <debug.h>
20 #include <daemon.h>
21 #include <radius_message.h>
22 #include <sa/authenticators/eap/eap_method.h>
23
24 typedef struct private_eap_ttls_peer_t private_eap_ttls_peer_t;
25
26 /**
27 * Private data of an eap_ttls_peer_t object.
28 */
29 struct private_eap_ttls_peer_t {
30
31 /**
32 * Public eap_ttls_peer_t interface.
33 */
34 eap_ttls_peer_t public;
35
36 /**
37 * Server identity
38 */
39 identification_t *server;
40
41 /**
42 * Peer identity
43 */
44 identification_t *peer;
45
46 /**
47 * Current EAP-TTLS state
48 */
49 bool start_phase2;
50
51 /**
52 * Current phase 2 EAP method
53 */
54 eap_method_t *method;
55
56 /**
57 * Pending outbound EAP message
58 */
59 eap_payload_t *out;
60
61 /**
62 * AVP handler
63 */
64 eap_ttls_avp_t *avp;
65 };
66
67 METHOD(tls_application_t, process, status_t,
68 private_eap_ttls_peer_t *this, bio_reader_t *reader)
69 {
70 chunk_t avp_data = chunk_empty;
71 chunk_t eap_data = chunk_empty;
72 status_t status;
73 payload_t *payload;
74 eap_payload_t *in;
75 eap_packet_t *pkt;
76 eap_code_t code;
77 eap_type_t type, received_type;
78 u_int32_t vendor, received_vendor;
79 u_int16_t eap_len;
80 size_t eap_pos = 0;
81 bool concatenated = FALSE;
82
83 do
84 {
85 status = this->avp->process(this->avp, reader, &avp_data);
86 switch (status)
87 {
88 case SUCCESS:
89 break;
90 case NEED_MORE:
91 DBG1(DBG_IKE, "need more AVP data");
92 return NEED_MORE;
93 case FAILED:
94 default:
95 return FAILED;
96 }
97
98 if (eap_data.len == 0)
99 {
100 if (avp_data.len < 4)
101 {
102 DBG1(DBG_IKE, "AVP size to small to contain EAP header");
103 chunk_free(&avp_data);
104 return FAILED;
105 }
106 pkt = (eap_packet_t*)avp_data.ptr;
107 eap_len = untoh16(&pkt->length);
108
109 if (eap_len <= avp_data.len)
110 {
111 /* standard: EAP packet contained in a single AVP */
112 eap_data = avp_data;
113 break;
114 }
115 else if (avp_data.len == MAX_RADIUS_ATTRIBUTE_SIZE)
116 {
117 /* non-standard: EAP packet segmented into multiple AVPs */
118 eap_data = chunk_alloc(eap_len);
119 concatenated = TRUE;
120 }
121 else
122 {
123 DBG1(DBG_IKE, "non-radius segmentation of EAP packet into AVPs");
124 chunk_free(&avp_data);
125 return FAILED;
126 }
127 }
128
129 if (avp_data.len > eap_data.len - eap_pos)
130 {
131 DBG1(DBG_IKE, "AVP size to large to fit into EAP packet");
132 chunk_free(&avp_data);
133 chunk_free(&eap_data);
134 return FAILED;
135 }
136 memcpy(eap_data.ptr + eap_pos, avp_data.ptr, avp_data.len);
137 eap_pos += avp_data.len;
138 chunk_free(&avp_data);
139 }
140 while (eap_pos < eap_data.len);
141
142 in = eap_payload_create_data(eap_data);
143 chunk_free(&eap_data);
144 payload = (payload_t*)in;
145
146 if (payload->verify(payload) != SUCCESS)
147 {
148 in->destroy(in);
149 return FAILED;
150 }
151 code = in->get_code(in);
152 received_type = in->get_type(in, &received_vendor);
153 DBG1(DBG_IKE, "received tunneled EAP-TTLS AVP%s [EAP/%N/%N]",
154 concatenated ? "s" : "",
155 eap_code_short_names, code,
156 eap_type_short_names, received_type);
157 if (code != EAP_REQUEST)
158 {
159 DBG1(DBG_IKE, "%N expected", eap_code_names, EAP_REQUEST);
160 in->destroy(in);
161 return FAILED;
162 }
163
164 /* yet another phase2 authentication? */
165 if (this->method)
166 {
167 type = this->method->get_type(this->method, &vendor);
168
169 if (type != received_type || vendor != received_vendor)
170 {
171 this->method->destroy(this->method);
172 this->method = NULL;
173 }
174 }
175
176 if (this->method == NULL)
177 {
178 if (received_vendor)
179 {
180 DBG1(DBG_IKE, "server requested vendor specific EAP method %d-%d "
181 "(id 0x%02X)", received_type, received_vendor,
182 in->get_identifier(in));
183 }
184 else
185 {
186 DBG1(DBG_IKE, "server requested %N authentication (id 0x%02X)",
187 eap_type_names, received_type, in->get_identifier(in));
188 }
189 this->method = charon->eap->create_instance(charon->eap,
190 received_type, received_vendor,
191 EAP_PEER, this->server, this->peer);
192 if (!this->method)
193 {
194 DBG1(DBG_IKE, "EAP method not supported");
195 this->out = eap_payload_create_nak(in->get_identifier(in));
196 in->destroy(in);
197 return NEED_MORE;
198 }
199 type = this->method->get_type(this->method, &vendor);
200 this->start_phase2 = FALSE;
201 }
202
203 status = this->method->process(this->method, in, &this->out);
204 in->destroy(in);
205
206 switch (status)
207 {
208 case SUCCESS:
209 this->method->destroy(this->method);
210 this->method = NULL;
211 /* fall through to NEED_MORE */
212 case NEED_MORE:
213 return NEED_MORE;
214 case FAILED:
215 default:
216 if (vendor)
217 {
218 DBG1(DBG_IKE, "vendor specific EAP method %d-%d failed",
219 type, vendor);
220 }
221 else
222 {
223 DBG1(DBG_IKE, "%N method failed", eap_type_names, type);
224 }
225 return FAILED;
226 }
227 }
228
229 METHOD(tls_application_t, build, status_t,
230 private_eap_ttls_peer_t *this, bio_writer_t *writer)
231 {
232 chunk_t data;
233 eap_code_t code;
234 eap_type_t type;
235 u_int32_t vendor;
236
237 if (this->method == NULL && this->start_phase2)
238 {
239 /* generate an EAP Identity response */
240 this->method = charon->eap->create_instance(charon->eap, EAP_IDENTITY,
241 0, EAP_PEER, this->server, this->peer);
242 if (this->method == NULL)
243 {
244 DBG1(DBG_IKE, "EAP_IDENTITY method not available");
245 return FAILED;
246 }
247 this->method->process(this->method, NULL, &this->out);
248 this->method->destroy(this->method);
249 this->method = NULL;
250 this->start_phase2 = FALSE;
251 }
252
253 if (this->out)
254 {
255 code = this->out->get_code(this->out);
256 type = this->out->get_type(this->out, &vendor);
257 DBG1(DBG_IKE, "sending tunneled EAP-TTLS AVP [EAP/%N/%N]",
258 eap_code_short_names, code, eap_type_short_names, type);
259
260 /* get the raw EAP message data */
261 data = this->out->get_data(this->out);
262 this->avp->build(this->avp, writer, data);
263
264 this->out->destroy(this->out);
265 this->out = NULL;
266 }
267 return INVALID_STATE;
268 }
269
270 METHOD(tls_application_t, destroy, void,
271 private_eap_ttls_peer_t *this)
272 {
273 this->server->destroy(this->server);
274 this->peer->destroy(this->peer);
275 DESTROY_IF(this->method);
276 DESTROY_IF(this->out);
277 this->avp->destroy(this->avp);
278 free(this);
279 }
280
281 /**
282 * See header
283 */
284 eap_ttls_peer_t *eap_ttls_peer_create(identification_t *server,
285 identification_t *peer)
286 {
287 private_eap_ttls_peer_t *this;
288
289 INIT(this,
290 .public = {
291 .application = {
292 .process = _process,
293 .build = _build,
294 .destroy = _destroy,
295 },
296 },
297 .server = server->clone(server),
298 .peer = peer->clone(peer),
299 .start_phase2 = TRUE,
300 .avp = eap_ttls_avp_create(),
301 );
302
303 return &this->public;
304 }