use base IMC ID if src IMC ID is not supported
[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 <pa_tnc/pa_tnc_msg.h>
20 #include <ietf/ietf_attr.h>
21 #include <ietf/ietf_attr_pa_tnc_error.h>
22 #include <ietf/ietf_attr_port_filter.h>
23 #include <ietf/ietf_attr_assess_result.h>
24
25 #include <tncif_pa_subtypes.h>
26
27 #include <pen/pen.h>
28 #include <utils/lexparser.h>
29 #include <debug.h>
30
31 #include <stdio.h>
32
33 /* IMC definitions */
34
35 static const char imc_name[] = "Scanner";
36
37 #define IMC_VENDOR_ID PEN_ITA
38 #define IMC_SUBTYPE PA_SUBTYPE_ITA_SCANNER
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, IMC_VENDOR_ID, IMC_SUBTYPE,
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, BUF_LEN-1, 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", 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 static TNC_Result send_message(TNC_ConnectionID connection_id)
233 {
234 linked_list_t *attr_list;
235 pa_tnc_attr_t *attr;
236 ietf_attr_port_filter_t *attr_port_filter;
237 TNC_Result result;
238
239 attr = ietf_attr_port_filter_create();
240 attr->set_noskip_flag(attr, TRUE);
241 attr_port_filter = (ietf_attr_port_filter_t*)attr;
242 if (!do_netstat(attr_port_filter))
243 {
244 attr->destroy(attr);
245 return TNC_RESULT_FATAL;
246 }
247 attr_list = linked_list_create();
248 attr_list->insert_last(attr_list, attr);
249 result = imc_scanner->send_message(imc_scanner, connection_id, FALSE, 0,
250 TNC_IMVID_ANY, attr_list);
251 attr_list->destroy(attr_list);
252
253 return result;
254 }
255
256 /**
257 * see section 3.8.3 of TCG TNC IF-IMC Specification 1.3
258 */
259 TNC_Result TNC_IMC_BeginHandshake(TNC_IMCID imc_id,
260 TNC_ConnectionID connection_id)
261 {
262 if (!imc_scanner)
263 {
264 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
265 return TNC_RESULT_NOT_INITIALIZED;
266 }
267 return send_message(connection_id);
268 }
269
270 static TNC_Result receive_message(TNC_IMCID imc_id,
271 TNC_ConnectionID connection_id,
272 TNC_UInt32 msg_flags,
273 chunk_t msg,
274 TNC_VendorID msg_vid,
275 TNC_MessageSubtype msg_subtype,
276 TNC_UInt32 src_imv_id,
277 TNC_UInt32 dst_imc_id)
278 {
279 pa_tnc_msg_t *pa_tnc_msg;
280 pa_tnc_attr_t *attr;
281 pen_type_t attr_type;
282 imc_state_t *state;
283 enumerator_t *enumerator;
284 TNC_Result result;
285 TNC_UInt32 target_imc_id;
286 bool fatal_error;
287
288 if (!imc_scanner)
289 {
290 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
291 return TNC_RESULT_NOT_INITIALIZED;
292 }
293
294 /* get current IMC state */
295 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
296 {
297 return TNC_RESULT_FATAL;
298 }
299
300 /* parse received PA-TNC message and automatically handle any errors */
301 result = imc_scanner->receive_message(imc_scanner, state, msg, msg_vid,
302 msg_subtype, src_imv_id, dst_imc_id, &pa_tnc_msg);
303
304 /* no parsed PA-TNC attributes available if an error occurred */
305 if (!pa_tnc_msg)
306 {
307 return result;
308 }
309 target_imc_id = (dst_imc_id == TNC_IMCID_ANY) ? imc_id : dst_imc_id;
310
311 /* preprocess any IETF standard error attributes */
312 fatal_error = pa_tnc_msg->process_ietf_std_errors(pa_tnc_msg);
313
314 /* analyze PA-TNC attributes */
315 enumerator = pa_tnc_msg->create_attribute_enumerator(pa_tnc_msg);
316 while (enumerator->enumerate(enumerator, &attr))
317 {
318 attr_type = attr->get_type(attr);
319
320 if (attr_type.vendor_id == PEN_IETF &&
321 attr_type.type == IETF_ATTR_ASSESSMENT_RESULT)
322 {
323 ietf_attr_assess_result_t *ietf_attr;
324
325 ietf_attr = (ietf_attr_assess_result_t*)attr;
326 state->set_result(state, target_imc_id,
327 ietf_attr->get_result(ietf_attr));
328 }
329 }
330 enumerator->destroy(enumerator);
331 pa_tnc_msg->destroy(pa_tnc_msg);
332
333 if (fatal_error)
334 {
335 return TNC_RESULT_FATAL;
336 }
337
338 /* if no assessment result is known then repeat the measurement */
339 return state->get_result(state, target_imc_id, NULL) ?
340 TNC_RESULT_SUCCESS : send_message(connection_id);
341 }
342
343 /**
344 * see section 3.8.4 of TCG TNC IF-IMC Specification 1.3
345
346 */
347 TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id,
348 TNC_ConnectionID connection_id,
349 TNC_BufferReference msg,
350 TNC_UInt32 msg_len,
351 TNC_MessageType msg_type)
352 {
353 TNC_VendorID msg_vid;
354 TNC_MessageSubtype msg_subtype;
355
356 msg_vid = msg_type >> 8;
357 msg_subtype = msg_type & TNC_SUBTYPE_ANY;
358
359 return receive_message(imc_id, connection_id, 0, chunk_create(msg, msg_len),
360 msg_vid, msg_subtype, 0, TNC_IMCID_ANY);
361 }
362
363 /**
364 * see section 3.8.6 of TCG TNC IF-IMV Specification 1.3
365 */
366 TNC_Result TNC_IMC_ReceiveMessageLong(TNC_IMCID imc_id,
367 TNC_ConnectionID connection_id,
368 TNC_UInt32 msg_flags,
369 TNC_BufferReference msg,
370 TNC_UInt32 msg_len,
371 TNC_VendorID msg_vid,
372 TNC_MessageSubtype msg_subtype,
373 TNC_UInt32 src_imv_id,
374 TNC_UInt32 dst_imc_id)
375 {
376 return receive_message(imc_id, connection_id, msg_flags,
377 chunk_create(msg, msg_len), msg_vid, msg_subtype,
378 src_imv_id, dst_imc_id);
379 }
380
381 /**
382 * see section 3.8.7 of TCG TNC IF-IMC Specification 1.3
383 */
384 TNC_Result TNC_IMC_BatchEnding(TNC_IMCID imc_id,
385 TNC_ConnectionID connection_id)
386 {
387 if (!imc_scanner)
388 {
389 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
390 return TNC_RESULT_NOT_INITIALIZED;
391 }
392 return TNC_RESULT_SUCCESS;
393 }
394
395 /**
396 * see section 3.8.8 of TCG TNC IF-IMC Specification 1.3
397 */
398 TNC_Result TNC_IMC_Terminate(TNC_IMCID imc_id)
399 {
400 if (!imc_scanner)
401 {
402 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
403 return TNC_RESULT_NOT_INITIALIZED;
404 }
405 imc_scanner->destroy(imc_scanner);
406 imc_scanner = NULL;
407
408 return TNC_RESULT_SUCCESS;
409 }
410
411 /**
412 * see section 4.2.8.1 of TCG TNC IF-IMC Specification 1.3
413 */
414 TNC_Result TNC_IMC_ProvideBindFunction(TNC_IMCID imc_id,
415 TNC_TNCC_BindFunctionPointer bind_function)
416 {
417 if (!imc_scanner)
418 {
419 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
420 return TNC_RESULT_NOT_INITIALIZED;
421 }
422 return imc_scanner->bind_functions(imc_scanner, bind_function);
423 }