updated strongswan.conf man page
[strongswan.git] / src / libimcv / plugins / imc_scanner / imc_scanner.c
1 /*
2 * Copyright (C) 2011-2012 Andreas Steffen
3 * 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 "imc_scanner_state.h"
17
18 #include <imc/imc_agent.h>
19 #include <imc/imc_msg.h>
20 #include <ietf/ietf_attr.h>
21 #include <ietf/ietf_attr_attr_request.h>
22 #include <ietf/ietf_attr_port_filter.h>
23
24 #include <tncif_pa_subtypes.h>
25
26 #include <pen/pen.h>
27 #include <utils/lexparser.h>
28 #include <utils/debug.h>
29
30 #include <stdio.h>
31
32 /* IMC definitions */
33
34 static const char imc_name[] = "Scanner";
35
36 static pen_type_t msg_types[] = {
37 { PEN_IETF, PA_SUBTYPE_IETF_VPN }
38 };
39
40 static imc_agent_t *imc_scanner;
41
42 /**
43 * see section 3.8.1 of TCG TNC IF-IMC Specification 1.3
44 */
45 TNC_Result TNC_IMC_Initialize(TNC_IMCID imc_id,
46 TNC_Version min_version,
47 TNC_Version max_version,
48 TNC_Version *actual_version)
49 {
50 if (imc_scanner)
51 {
52 DBG1(DBG_IMC, "IMC \"%s\" has already been initialized", imc_name);
53 return TNC_RESULT_ALREADY_INITIALIZED;
54 }
55 imc_scanner = imc_agent_create(imc_name, msg_types, countof(msg_types),
56 imc_id, actual_version);
57 if (!imc_scanner)
58 {
59 return TNC_RESULT_FATAL;
60 }
61 if (min_version > TNC_IFIMC_VERSION_1 || max_version < TNC_IFIMC_VERSION_1)
62 {
63 DBG1(DBG_IMC, "no common IF-IMC version");
64 return TNC_RESULT_NO_COMMON_VERSION;
65 }
66 return TNC_RESULT_SUCCESS;
67 }
68
69 /**
70 * see section 3.8.2 of TCG TNC IF-IMC Specification 1.3
71 */
72 TNC_Result TNC_IMC_NotifyConnectionChange(TNC_IMCID imc_id,
73 TNC_ConnectionID connection_id,
74 TNC_ConnectionState new_state)
75 {
76 imc_state_t *state;
77
78 if (!imc_scanner)
79 {
80 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
81 return TNC_RESULT_NOT_INITIALIZED;
82 }
83 switch (new_state)
84 {
85 case TNC_CONNECTION_STATE_CREATE:
86 state = imc_scanner_state_create(connection_id);
87 return imc_scanner->create_state(imc_scanner, state);
88 case TNC_CONNECTION_STATE_HANDSHAKE:
89 if (imc_scanner->change_state(imc_scanner, connection_id, new_state,
90 &state) != TNC_RESULT_SUCCESS)
91 {
92 return TNC_RESULT_FATAL;
93 }
94 state->set_result(state, imc_id,
95 TNC_IMV_EVALUATION_RESULT_DONT_KNOW);
96 return TNC_RESULT_SUCCESS;
97 case TNC_CONNECTION_STATE_DELETE:
98 return imc_scanner->delete_state(imc_scanner, connection_id);
99 default:
100 return imc_scanner->change_state(imc_scanner, connection_id,
101 new_state, NULL);
102 }
103 }
104
105 /**
106 * Determine all TCP and UDP server sockets listening on physical interfaces
107 */
108 static bool do_netstat(ietf_attr_port_filter_t *attr)
109 {
110 FILE *file;
111 char buf[BUF_LEN];
112 chunk_t line, token;
113 int n = 0;
114 bool success = FALSE;
115 const char loopback_v4[] = "127.0.0.1";
116 const char loopback_v6[] = "::1";
117
118 /* Open a pipe stream for reading the output of the netstat commmand */
119 file = popen("/bin/netstat -n -l -p -4 -6 --inet", "r");
120 if (!file)
121 {
122 DBG1(DBG_IMC, "failed to run netstat command");
123 return FALSE;
124 }
125
126 /* Read the output a line at a time */
127 while (fgets(buf, sizeof(buf), file))
128 {
129 u_char *pos;
130 u_int8_t new_protocol, protocol;
131 u_int16_t new_port, port;
132 int i;
133 enumerator_t *enumerator;
134 bool allowed, found = FALSE;
135
136 DBG2(DBG_IMC, "%.*s", (int)(strlen(buf)-1), buf);
137
138 if (n++ < 2)
139 {
140 /* skip the first two header lines */
141 continue;
142 }
143 line = chunk_create(buf, strlen(buf));
144
145 /* Extract the IP protocol type */
146 if (!extract_token(&token, ' ', &line))
147 {
148 DBG1(DBG_IMC, "protocol field in netstat output not found");
149 goto end;
150 }
151 if (match("tcp", &token) || match("tcp6", &token))
152 {
153 new_protocol = IPPROTO_TCP;
154 }
155 else if (match("udp", &token) || match("udp6", &token))
156 {
157 new_protocol = IPPROTO_UDP;
158 }
159 else
160 {
161 DBG1(DBG_IMC, "skipped unknown IP protocol in netstat output");
162 continue;
163 }
164
165 /* Skip the Recv-Q and Send-Q fields */
166 for (i = 0; i < 3; i++)
167 {
168 if (!eat_whitespace(&line) || !extract_token(&token, ' ', &line))
169 {
170 token = chunk_empty;
171 break;
172 }
173 }
174 if (token.len == 0)
175 {
176 DBG1(DBG_IMC, "local address field in netstat output not found");
177 goto end;
178 }
179
180 /* Find the local port appended to the local address */
181 pos = token.ptr + token.len;
182 while (*--pos != ':' && --token.len);
183 if (*pos != ':')
184 {
185 DBG1(DBG_IMC, "local port field in netstat output not found");
186 goto end;
187 }
188 token.len--;
189
190 /* ignore ports of IPv4 and IPv6 loopback interfaces */
191 if ((token.len == strlen(loopback_v4) &&
192 memeq(loopback_v4, token.ptr, token.len)) ||
193 (token.len == strlen(loopback_v6) &&
194 memeq(loopback_v6, token.ptr, token.len)))
195 {
196 continue;
197 }
198
199 /* convert the port string to an integer */
200 new_port = atoi(pos+1);
201
202 /* check if the there is already a port entry */
203 enumerator = attr->create_port_enumerator(attr);
204 while (enumerator->enumerate(enumerator, &allowed, &protocol, &port))
205 {
206 if (new_port == port && new_protocol == protocol)
207 {
208 found = TRUE;
209 }
210 }
211 enumerator->destroy(enumerator);
212
213 /* Skip the duplicate port entry */
214 if (found)
215 {
216 continue;
217 }
218
219 /* Add new port entry */
220 attr->add_port(attr, FALSE, new_protocol, new_port);
221 }
222
223 /* Successfully completed the parsing of the netstat output */
224 success = TRUE;
225
226 end:
227 /* Close the pipe stream */
228 pclose(file);
229 return success;
230 }
231
232 /**
233 * Add IETF Port Filter attribute to the send queue
234 */
235 static TNC_Result add_port_filter(imc_msg_t *msg)
236 {
237 pa_tnc_attr_t *attr;
238 ietf_attr_port_filter_t *attr_port_filter;
239
240 attr = ietf_attr_port_filter_create();
241 attr->set_noskip_flag(attr, TRUE);
242 attr_port_filter = (ietf_attr_port_filter_t*)attr;
243 if (!do_netstat(attr_port_filter))
244 {
245 attr->destroy(attr);
246 return TNC_RESULT_FATAL;
247 }
248 msg->add_attribute(msg, attr);
249
250 return TNC_RESULT_SUCCESS;
251 }
252
253 /**
254 * see section 3.8.3 of TCG TNC IF-IMC Specification 1.3
255 */
256 TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id,
257 TNC_ConnectionID connection_id)
258 {
259 imc_state_t *state;
260 imc_msg_t *out_msg;
261 TNC_Result result = TNC_RESULT_SUCCESS;
262
263 if (!imc_scanner)
264 {
265 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
266 return TNC_RESULT_NOT_INITIALIZED;
267 }
268 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
269 {
270 return TNC_RESULT_FATAL;
271 }
272 if (lib->settings->get_bool(lib->settings,
273 "libimcv.plugins.imc-scanner.push_info", TRUE))
274 {
275 out_msg = imc_msg_create(imc_scanner, state, connection_id, imc_id,
276 TNC_IMVID_ANY, msg_types[0]);
277 result = add_port_filter(out_msg);
278 if (result == TNC_RESULT_SUCCESS)
279 {
280 /* send PA-TNC message with the excl flag not set */
281 result = out_msg->send(out_msg, FALSE);
282 }
283 out_msg->destroy(out_msg);
284 }
285
286 return result;
287 }
288
289 static TNC_Result receive_message(imc_msg_t *in_msg)
290 {
291 imc_msg_t *out_msg;
292 enumerator_t *enumerator;
293 pa_tnc_attr_t *attr;
294 pen_type_t attr_type;
295 TNC_Result result = TNC_RESULT_SUCCESS;
296 bool fatal_error = FALSE;
297
298 /* parse received PA-TNC message and handle local and remote errors */
299 result = in_msg->receive(in_msg, &fatal_error);
300 if (result != TNC_RESULT_SUCCESS)
301 {
302 return result;
303 }
304 out_msg = imc_msg_create_as_reply(in_msg);
305
306 /* analyze PA-TNC attributes */
307 enumerator = in_msg->create_attribute_enumerator(in_msg);
308 while (enumerator->enumerate(enumerator, &attr))
309 {
310 attr_type = attr->get_type(attr);
311
312 if (attr_type.vendor_id != PEN_IETF)
313 {
314 continue;
315 }
316 if (attr_type.type == IETF_ATTR_ATTRIBUTE_REQUEST)
317 {
318 ietf_attr_attr_request_t *attr_cast;
319 pen_type_t *entry;
320 enumerator_t *e;
321
322 attr_cast = (ietf_attr_attr_request_t*)attr;
323
324 e = attr_cast->create_enumerator(attr_cast);
325 while (e->enumerate(e, &entry))
326 {
327 if (entry->vendor_id != PEN_IETF)
328 {
329 continue;
330 }
331 switch (entry->type)
332 {
333 case IETF_ATTR_PORT_FILTER:
334 result = add_port_filter(out_msg);
335 break;
336 default:
337 break;
338 }
339 }
340 e->destroy(e);
341 }
342 }
343 enumerator->destroy(enumerator);
344
345 if (fatal_error)
346 {
347 result = TNC_RESULT_FATAL;
348 }
349 else if (result == TNC_RESULT_SUCCESS)
350 {
351 result = out_msg->send(out_msg, TRUE);
352 }
353 out_msg->destroy(out_msg);
354
355 return result;
356 }
357
358 /**
359 * see section 3.8.4 of TCG TNC IF-IMC Specification 1.3
360
361 */
362 TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id,
363 TNC_ConnectionID connection_id,
364 TNC_BufferReference msg,
365 TNC_UInt32 msg_len,
366 TNC_MessageType msg_type)
367 {
368 imc_state_t *state;
369 imc_msg_t *in_msg;
370 TNC_Result result;
371
372 if (!imc_scanner)
373 {
374 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
375 return TNC_RESULT_NOT_INITIALIZED;
376 }
377 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
378 {
379 return TNC_RESULT_FATAL;
380 }
381
382 in_msg = imc_msg_create_from_data(imc_scanner, state, connection_id,
383 msg_type, chunk_create(msg, msg_len));
384 result = receive_message(in_msg);
385 in_msg->destroy(in_msg);
386
387 return result;
388 }
389
390 /**
391 * see section 3.8.6 of TCG TNC IF-IMV Specification 1.3
392 */
393 TNC_Result TNC_IMC_ReceiveMessageLong(TNC_IMCID imc_id,
394 TNC_ConnectionID connection_id,
395 TNC_UInt32 msg_flags,
396 TNC_BufferReference msg,
397 TNC_UInt32 msg_len,
398 TNC_VendorID msg_vid,
399 TNC_MessageSubtype msg_subtype,
400 TNC_UInt32 src_imv_id,
401 TNC_UInt32 dst_imc_id)
402 {
403 imc_state_t *state;
404 imc_msg_t *in_msg;
405 TNC_Result result;
406
407 if (!imc_scanner)
408 {
409 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
410 return TNC_RESULT_NOT_INITIALIZED;
411 }
412 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
413 {
414 return TNC_RESULT_FATAL;
415 }
416 in_msg = imc_msg_create_from_long_data(imc_scanner, state, connection_id,
417 src_imv_id, dst_imc_id, msg_vid, msg_subtype,
418 chunk_create(msg, msg_len));
419 result = receive_message(in_msg);
420 in_msg->destroy(in_msg);
421
422 return result;
423 }
424
425 /**
426 * see section 3.8.7 of TCG TNC IF-IMC Specification 1.3
427 */
428 TNC_Result TNC_IMC_BatchEnding(TNC_IMCID imc_id,
429 TNC_ConnectionID connection_id)
430 {
431 if (!imc_scanner)
432 {
433 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
434 return TNC_RESULT_NOT_INITIALIZED;
435 }
436 return TNC_RESULT_SUCCESS;
437 }
438
439 /**
440 * see section 3.8.8 of TCG TNC IF-IMC Specification 1.3
441 */
442 TNC_Result TNC_IMC_Terminate(TNC_IMCID imc_id)
443 {
444 if (!imc_scanner)
445 {
446 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
447 return TNC_RESULT_NOT_INITIALIZED;
448 }
449 imc_scanner->destroy(imc_scanner);
450 imc_scanner = NULL;
451
452 return TNC_RESULT_SUCCESS;
453 }
454
455 /**
456 * see section 4.2.8.1 of TCG TNC IF-IMC Specification 1.3
457 */
458 TNC_Result TNC_IMC_ProvideBindFunction(TNC_IMCID imc_id,
459 TNC_TNCC_BindFunctionPointer bind_function)
460 {
461 if (!imc_scanner)
462 {
463 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
464 return TNC_RESULT_NOT_INITIALIZED;
465 }
466 return imc_scanner->bind_functions(imc_scanner, bind_function);
467 }