libimcv: Move settings to <ns>.imcv and <ns>.plugins with fallback
[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 system_v4[] = "127.0.1.1";
116 const char loopback_v4[] = "127.0.0.1";
117 const char loopback_v6[] = "::1";
118
119 /* Open a pipe stream for reading the output of the netstat commmand */
120 file = popen("/bin/netstat -n -l -p -4 -6 --inet", "r");
121 if (!file)
122 {
123 DBG1(DBG_IMC, "failed to run netstat command");
124 return FALSE;
125 }
126
127 /* Read the output a line at a time */
128 while (fgets(buf, sizeof(buf), file))
129 {
130 u_char *pos;
131 u_int8_t new_protocol, protocol;
132 u_int16_t new_port, port;
133 int i;
134 enumerator_t *enumerator;
135 bool allowed, found = FALSE;
136
137 DBG2(DBG_IMC, "%.*s", (int)(strlen(buf)-1), buf);
138
139 if (n++ < 2)
140 {
141 /* skip the first two header lines */
142 continue;
143 }
144 line = chunk_create(buf, strlen(buf));
145
146 /* Extract the IP protocol type */
147 if (!extract_token(&token, ' ', &line))
148 {
149 DBG1(DBG_IMC, "protocol field in netstat output not found");
150 goto end;
151 }
152 if (match("tcp", &token) || match("tcp6", &token))
153 {
154 new_protocol = IPPROTO_TCP;
155 }
156 else if (match("udp", &token) || match("udp6", &token))
157 {
158 new_protocol = IPPROTO_UDP;
159 }
160 else
161 {
162 DBG1(DBG_IMC, "skipped unknown IP protocol in netstat output");
163 continue;
164 }
165
166 /* Skip the Recv-Q and Send-Q fields */
167 for (i = 0; i < 3; i++)
168 {
169 if (!eat_whitespace(&line) || !extract_token(&token, ' ', &line))
170 {
171 token = chunk_empty;
172 break;
173 }
174 }
175 if (token.len == 0)
176 {
177 DBG1(DBG_IMC, "local address field in netstat output not found");
178 goto end;
179 }
180
181 /* Find the local port appended to the local address */
182 pos = token.ptr + token.len;
183 while (*--pos != ':' && --token.len);
184 if (*pos != ':')
185 {
186 DBG1(DBG_IMC, "local port field in netstat output not found");
187 goto end;
188 }
189 token.len--;
190
191 /* ignore ports of IPv4 and IPv6 loopback interfaces
192 and the internal system IPv4 address */
193 if ((token.len == strlen(system_v4) &&
194 memeq(system_v4, token.ptr, token.len)) ||
195 (token.len == strlen(loopback_v4) &&
196 memeq(loopback_v4, token.ptr, token.len)) ||
197 (token.len == strlen(loopback_v6) &&
198 memeq(loopback_v6, token.ptr, token.len)))
199 {
200 continue;
201 }
202
203 /* convert the port string to an integer */
204 new_port = atoi(pos+1);
205
206 /* check if the there is already a port entry */
207 enumerator = attr->create_port_enumerator(attr);
208 while (enumerator->enumerate(enumerator, &allowed, &protocol, &port))
209 {
210 if (new_port == port && new_protocol == protocol)
211 {
212 found = TRUE;
213 }
214 }
215 enumerator->destroy(enumerator);
216
217 /* Skip the duplicate port entry */
218 if (found)
219 {
220 continue;
221 }
222
223 /* Add new port entry */
224 attr->add_port(attr, FALSE, new_protocol, new_port);
225 }
226
227 /* Successfully completed the parsing of the netstat output */
228 success = TRUE;
229
230 end:
231 /* Close the pipe stream */
232 pclose(file);
233 return success;
234 }
235
236 /**
237 * Add IETF Port Filter attribute to the send queue
238 */
239 static TNC_Result add_port_filter(imc_msg_t *msg)
240 {
241 pa_tnc_attr_t *attr;
242 ietf_attr_port_filter_t *attr_port_filter;
243
244 attr = ietf_attr_port_filter_create();
245 attr->set_noskip_flag(attr, TRUE);
246 attr_port_filter = (ietf_attr_port_filter_t*)attr;
247 if (!do_netstat(attr_port_filter))
248 {
249 attr->destroy(attr);
250 return TNC_RESULT_FATAL;
251 }
252 msg->add_attribute(msg, attr);
253
254 return TNC_RESULT_SUCCESS;
255 }
256
257 /**
258 * see section 3.8.3 of TCG TNC IF-IMC Specification 1.3
259 */
260 TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id,
261 TNC_ConnectionID connection_id)
262 {
263 imc_state_t *state;
264 imc_msg_t *out_msg;
265 TNC_Result result = TNC_RESULT_SUCCESS;
266
267 if (!imc_scanner)
268 {
269 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
270 return TNC_RESULT_NOT_INITIALIZED;
271 }
272 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
273 {
274 return TNC_RESULT_FATAL;
275 }
276 if (lib->settings->get_bool(lib->settings,
277 "%s.plugins.imc-scanner.push_info", TRUE, lib->ns))
278 {
279 out_msg = imc_msg_create(imc_scanner, state, connection_id, imc_id,
280 TNC_IMVID_ANY, msg_types[0]);
281 result = add_port_filter(out_msg);
282 if (result == TNC_RESULT_SUCCESS)
283 {
284 /* send PA-TNC message with the excl flag not set */
285 result = out_msg->send(out_msg, FALSE);
286 }
287 out_msg->destroy(out_msg);
288 }
289
290 return result;
291 }
292
293 static TNC_Result receive_message(imc_msg_t *in_msg)
294 {
295 imc_msg_t *out_msg;
296 enumerator_t *enumerator;
297 pa_tnc_attr_t *attr;
298 pen_type_t attr_type;
299 TNC_Result result = TNC_RESULT_SUCCESS;
300 bool fatal_error = FALSE;
301
302 /* parse received PA-TNC message and handle local and remote errors */
303 result = in_msg->receive(in_msg, &fatal_error);
304 if (result != TNC_RESULT_SUCCESS)
305 {
306 return result;
307 }
308 out_msg = imc_msg_create_as_reply(in_msg);
309
310 /* analyze PA-TNC attributes */
311 enumerator = in_msg->create_attribute_enumerator(in_msg);
312 while (enumerator->enumerate(enumerator, &attr))
313 {
314 attr_type = attr->get_type(attr);
315
316 if (attr_type.vendor_id != PEN_IETF)
317 {
318 continue;
319 }
320 if (attr_type.type == IETF_ATTR_ATTRIBUTE_REQUEST)
321 {
322 ietf_attr_attr_request_t *attr_cast;
323 pen_type_t *entry;
324 enumerator_t *e;
325
326 attr_cast = (ietf_attr_attr_request_t*)attr;
327
328 e = attr_cast->create_enumerator(attr_cast);
329 while (e->enumerate(e, &entry))
330 {
331 if (entry->vendor_id != PEN_IETF)
332 {
333 continue;
334 }
335 switch (entry->type)
336 {
337 case IETF_ATTR_PORT_FILTER:
338 result = add_port_filter(out_msg);
339 break;
340 default:
341 break;
342 }
343 }
344 e->destroy(e);
345 }
346 }
347 enumerator->destroy(enumerator);
348
349 if (fatal_error)
350 {
351 result = TNC_RESULT_FATAL;
352 }
353 else if (result == TNC_RESULT_SUCCESS)
354 {
355 result = out_msg->send(out_msg, TRUE);
356 }
357 out_msg->destroy(out_msg);
358
359 return result;
360 }
361
362 /**
363 * see section 3.8.4 of TCG TNC IF-IMC Specification 1.3
364
365 */
366 TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id,
367 TNC_ConnectionID connection_id,
368 TNC_BufferReference msg,
369 TNC_UInt32 msg_len,
370 TNC_MessageType msg_type)
371 {
372 imc_state_t *state;
373 imc_msg_t *in_msg;
374 TNC_Result result;
375
376 if (!imc_scanner)
377 {
378 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
379 return TNC_RESULT_NOT_INITIALIZED;
380 }
381 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
382 {
383 return TNC_RESULT_FATAL;
384 }
385
386 in_msg = imc_msg_create_from_data(imc_scanner, state, connection_id,
387 msg_type, chunk_create(msg, msg_len));
388 result = receive_message(in_msg);
389 in_msg->destroy(in_msg);
390
391 return result;
392 }
393
394 /**
395 * see section 3.8.6 of TCG TNC IF-IMV Specification 1.3
396 */
397 TNC_Result TNC_IMC_ReceiveMessageLong(TNC_IMCID imc_id,
398 TNC_ConnectionID connection_id,
399 TNC_UInt32 msg_flags,
400 TNC_BufferReference msg,
401 TNC_UInt32 msg_len,
402 TNC_VendorID msg_vid,
403 TNC_MessageSubtype msg_subtype,
404 TNC_UInt32 src_imv_id,
405 TNC_UInt32 dst_imc_id)
406 {
407 imc_state_t *state;
408 imc_msg_t *in_msg;
409 TNC_Result result;
410
411 if (!imc_scanner)
412 {
413 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
414 return TNC_RESULT_NOT_INITIALIZED;
415 }
416 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
417 {
418 return TNC_RESULT_FATAL;
419 }
420 in_msg = imc_msg_create_from_long_data(imc_scanner, state, connection_id,
421 src_imv_id, dst_imc_id, msg_vid, msg_subtype,
422 chunk_create(msg, msg_len));
423 result = receive_message(in_msg);
424 in_msg->destroy(in_msg);
425
426 return result;
427 }
428
429 /**
430 * see section 3.8.7 of TCG TNC IF-IMC Specification 1.3
431 */
432 TNC_Result TNC_IMC_BatchEnding(TNC_IMCID imc_id,
433 TNC_ConnectionID connection_id)
434 {
435 if (!imc_scanner)
436 {
437 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
438 return TNC_RESULT_NOT_INITIALIZED;
439 }
440 return TNC_RESULT_SUCCESS;
441 }
442
443 /**
444 * see section 3.8.8 of TCG TNC IF-IMC Specification 1.3
445 */
446 TNC_Result TNC_IMC_Terminate(TNC_IMCID imc_id)
447 {
448 if (!imc_scanner)
449 {
450 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
451 return TNC_RESULT_NOT_INITIALIZED;
452 }
453 imc_scanner->destroy(imc_scanner);
454 imc_scanner = NULL;
455
456 return TNC_RESULT_SUCCESS;
457 }
458
459 /**
460 * see section 4.2.8.1 of TCG TNC IF-IMC Specification 1.3
461 */
462 TNC_Result TNC_IMC_ProvideBindFunction(TNC_IMCID imc_id,
463 TNC_TNCC_BindFunctionPointer bind_function)
464 {
465 if (!imc_scanner)
466 {
467 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
468 return TNC_RESULT_NOT_INITIALIZED;
469 }
470 return imc_scanner->bind_functions(imc_scanner, bind_function);
471 }