openssl: Use dynamically allocated array to determine EC curves
[strongswan.git] / src / libimcv / plugins / imc_scanner / imc_scanner.c
1 /*
2 * Copyright (C) 2011-2015 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_FIREWALL }
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_DELETE:
89 return imc_scanner->delete_state(imc_scanner, connection_id);
90 default:
91 return imc_scanner->change_state(imc_scanner, connection_id,
92 new_state, NULL);
93 }
94 }
95
96 /**
97 * Determine all TCP and UDP server sockets listening on physical interfaces
98 */
99 static bool do_netstat(ietf_attr_port_filter_t *attr)
100 {
101 FILE *file;
102 char buf[BUF_LEN];
103 chunk_t line, token;
104 int n = 0;
105 bool success = FALSE;
106 const char system_v4[] = "127.0.1.1";
107 const char loopback_v4[] = "127.0.0.1";
108 const char loopback_v6[] = "::1";
109
110 /* Open a pipe stream for reading the output of the netstat command */
111 file = popen("/bin/netstat -n -l -p -4 -6 --inet", "r");
112 if (!file)
113 {
114 DBG1(DBG_IMC, "failed to run netstat command");
115 return FALSE;
116 }
117
118 /* Read the output a line at a time */
119 while (fgets(buf, sizeof(buf), file))
120 {
121 u_char *pos;
122 uint8_t new_protocol, protocol;
123 uint16_t new_port, port;
124 int i;
125 enumerator_t *enumerator;
126 bool allowed, found = FALSE;
127
128 DBG2(DBG_IMC, "%.*s", (int)(strlen(buf)-1), buf);
129
130 if (n++ < 2)
131 {
132 /* skip the first two header lines */
133 continue;
134 }
135 line = chunk_create(buf, strlen(buf));
136
137 /* Extract the IP protocol type */
138 if (!extract_token(&token, ' ', &line))
139 {
140 DBG1(DBG_IMC, "protocol field in netstat output not found");
141 goto end;
142 }
143 if (match("tcp", &token) || match("tcp6", &token))
144 {
145 new_protocol = IPPROTO_TCP;
146 }
147 else if (match("udp", &token) || match("udp6", &token))
148 {
149 new_protocol = IPPROTO_UDP;
150 }
151 else
152 {
153 DBG1(DBG_IMC, "skipped unknown IP protocol in netstat output");
154 continue;
155 }
156
157 /* Skip the Recv-Q and Send-Q fields */
158 for (i = 0; i < 3; i++)
159 {
160 if (!eat_whitespace(&line) || !extract_token(&token, ' ', &line))
161 {
162 token = chunk_empty;
163 break;
164 }
165 }
166 if (token.len == 0)
167 {
168 DBG1(DBG_IMC, "local address field in netstat output not found");
169 goto end;
170 }
171
172 /* Find the local port appended to the local address */
173 pos = token.ptr + token.len;
174 while (*--pos != ':' && --token.len);
175 if (*pos != ':')
176 {
177 DBG1(DBG_IMC, "local port field in netstat output not found");
178 goto end;
179 }
180 token.len--;
181
182 /* ignore ports of IPv4 and IPv6 loopback interfaces
183 and the internal system IPv4 address */
184 if ((token.len == strlen(system_v4) &&
185 memeq(system_v4, token.ptr, token.len)) ||
186 (token.len == strlen(loopback_v4) &&
187 memeq(loopback_v4, token.ptr, token.len)) ||
188 (token.len == strlen(loopback_v6) &&
189 memeq(loopback_v6, token.ptr, token.len)))
190 {
191 continue;
192 }
193
194 /* convert the port string to an integer */
195 new_port = atoi(pos+1);
196
197 /* check if the there is already a port entry */
198 enumerator = attr->create_port_enumerator(attr);
199 while (enumerator->enumerate(enumerator, &allowed, &protocol, &port))
200 {
201 if (new_port == port && new_protocol == protocol)
202 {
203 found = TRUE;
204 }
205 }
206 enumerator->destroy(enumerator);
207
208 /* Skip the duplicate port entry */
209 if (found)
210 {
211 continue;
212 }
213
214 /* Add new port entry */
215 attr->add_port(attr, FALSE, new_protocol, new_port);
216 }
217
218 /* Successfully completed the parsing of the netstat output */
219 success = TRUE;
220
221 end:
222 /* Close the pipe stream */
223 pclose(file);
224 return success;
225 }
226
227 /**
228 * Add IETF Port Filter attribute to the send queue
229 */
230 static TNC_Result add_port_filter(imc_msg_t *msg)
231 {
232 pa_tnc_attr_t *attr;
233 ietf_attr_port_filter_t *attr_port_filter;
234
235 attr = ietf_attr_port_filter_create(pen_type_create(PEN_IETF,
236 IETF_ATTR_PORT_FILTER));
237 attr->set_noskip_flag(attr, TRUE);
238 attr_port_filter = (ietf_attr_port_filter_t*)attr;
239 if (!do_netstat(attr_port_filter))
240 {
241 attr->destroy(attr);
242 return TNC_RESULT_FATAL;
243 }
244 msg->add_attribute(msg, attr);
245
246 return TNC_RESULT_SUCCESS;
247 }
248
249 /**
250 * see section 3.8.3 of TCG TNC IF-IMC Specification 1.3
251 */
252 TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id,
253 TNC_ConnectionID connection_id)
254 {
255 imc_state_t *state;
256 imc_msg_t *out_msg;
257 TNC_Result result = TNC_RESULT_SUCCESS;
258
259 if (!imc_scanner)
260 {
261 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
262 return TNC_RESULT_NOT_INITIALIZED;
263 }
264 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
265 {
266 return TNC_RESULT_FATAL;
267 }
268 if (lib->settings->get_bool(lib->settings,
269 "%s.plugins.imc-scanner.push_info", TRUE, lib->ns))
270 {
271 out_msg = imc_msg_create(imc_scanner, state, connection_id, imc_id,
272 TNC_IMVID_ANY, msg_types[0]);
273 result = add_port_filter(out_msg);
274 if (result == TNC_RESULT_SUCCESS)
275 {
276 /* send PA-TNC message with the excl flag not set */
277 result = out_msg->send(out_msg, FALSE);
278 }
279 out_msg->destroy(out_msg);
280 }
281
282 return result;
283 }
284
285 static TNC_Result receive_message(imc_msg_t *in_msg)
286 {
287 imc_msg_t *out_msg;
288 enumerator_t *enumerator;
289 pa_tnc_attr_t *attr;
290 pen_type_t attr_type;
291 TNC_Result result = TNC_RESULT_SUCCESS;
292 bool fatal_error = FALSE;
293
294 /* generate an outgoing PA-TNC message - we might need it */
295 out_msg = imc_msg_create_as_reply(in_msg);
296
297 /* parse received PA-TNC message and handle local and remote errors */
298 result = in_msg->receive(in_msg, out_msg, &fatal_error);
299 if (result != TNC_RESULT_SUCCESS)
300 {
301 out_msg->destroy(out_msg);
302 return result;
303 }
304
305 /* analyze PA-TNC attributes */
306 enumerator = in_msg->create_attribute_enumerator(in_msg);
307 while (enumerator->enumerate(enumerator, &attr))
308 {
309 attr_type = attr->get_type(attr);
310
311 if (attr_type.vendor_id != PEN_IETF)
312 {
313 continue;
314 }
315 if (attr_type.type == IETF_ATTR_ATTRIBUTE_REQUEST)
316 {
317 ietf_attr_attr_request_t *attr_cast;
318 pen_type_t *entry;
319 enumerator_t *e;
320
321 attr_cast = (ietf_attr_attr_request_t*)attr;
322
323 e = attr_cast->create_enumerator(attr_cast);
324 while (e->enumerate(e, &entry))
325 {
326 if (entry->vendor_id != PEN_IETF)
327 {
328 continue;
329 }
330 switch (entry->type)
331 {
332 case IETF_ATTR_PORT_FILTER:
333 result = add_port_filter(out_msg);
334 break;
335 default:
336 break;
337 }
338 }
339 e->destroy(e);
340 }
341 }
342 enumerator->destroy(enumerator);
343
344 if (fatal_error)
345 {
346 result = TNC_RESULT_FATAL;
347 }
348 else if (result == TNC_RESULT_SUCCESS)
349 {
350 /* send PA-TNC message with the EXCL flag set */
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 }