introduced sending of standard IETF Assessment Result PA-TNC attribute by IMVs
[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 bool fatal_error;
286
287 if (!imc_scanner)
288 {
289 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
290 return TNC_RESULT_NOT_INITIALIZED;
291 }
292
293 /* get current IMC state */
294 if (!imc_scanner->get_state(imc_scanner, connection_id, &state))
295 {
296 return TNC_RESULT_FATAL;
297 }
298
299 /* parse received PA-TNC message and automatically handle any errors */
300 result = imc_scanner->receive_message(imc_scanner, state, msg, msg_vid,
301 msg_subtype, src_imv_id, dst_imc_id, &pa_tnc_msg);
302
303 /* no parsed PA-TNC attributes available if an error occurred */
304 if (!pa_tnc_msg)
305 {
306 return result;
307 }
308
309 /* preprocess any IETF standard error attributes */
310 fatal_error = pa_tnc_msg->process_ietf_std_errors(pa_tnc_msg);
311
312 /* analyze PA-TNC attributes */
313 enumerator = pa_tnc_msg->create_attribute_enumerator(pa_tnc_msg);
314 while (enumerator->enumerate(enumerator, &attr))
315 {
316 attr_type = attr->get_type(attr);
317
318 if (attr_type.vendor_id == PEN_IETF &&
319 attr_type.type == IETF_ATTR_ASSESSMENT_RESULT)
320 {
321 ietf_attr_assess_result_t *ietf_attr;
322
323 ietf_attr = (ietf_attr_assess_result_t*)attr;
324 state->set_result(state, dst_imc_id,
325 ietf_attr->get_result(ietf_attr));
326 }
327 }
328 enumerator->destroy(enumerator);
329 pa_tnc_msg->destroy(pa_tnc_msg);
330
331 if (fatal_error)
332 {
333 return TNC_RESULT_FATAL;
334 }
335
336 /* if no assessment result is known then repeat the measurement */
337 return state->get_result(state, dst_imc_id, NULL) ?
338 TNC_RESULT_SUCCESS : send_message(connection_id);
339 }
340
341 /**
342 * see section 3.8.4 of TCG TNC IF-IMC Specification 1.3
343
344 */
345 TNC_Result TNC_IMC_ReceiveMessage(TNC_IMCID imc_id,
346 TNC_ConnectionID connection_id,
347 TNC_BufferReference msg,
348 TNC_UInt32 msg_len,
349 TNC_MessageType msg_type)
350 {
351 TNC_VendorID msg_vid;
352 TNC_MessageSubtype msg_subtype;
353
354 msg_vid = msg_type >> 8;
355 msg_subtype = msg_type & TNC_SUBTYPE_ANY;
356
357 return receive_message(imc_id, connection_id, 0, chunk_create(msg, msg_len),
358 msg_vid, msg_subtype, 0, TNC_IMCID_ANY);
359 }
360
361 /**
362 * see section 3.8.6 of TCG TNC IF-IMV Specification 1.3
363 */
364 TNC_Result TNC_IMC_ReceiveMessageLong(TNC_IMCID imc_id,
365 TNC_ConnectionID connection_id,
366 TNC_UInt32 msg_flags,
367 TNC_BufferReference msg,
368 TNC_UInt32 msg_len,
369 TNC_VendorID msg_vid,
370 TNC_MessageSubtype msg_subtype,
371 TNC_UInt32 src_imv_id,
372 TNC_UInt32 dst_imc_id)
373 {
374 return receive_message(imc_id, connection_id, msg_flags,
375 chunk_create(msg, msg_len), msg_vid, msg_subtype,
376 src_imv_id, dst_imc_id);
377 }
378
379 /**
380 * see section 3.8.7 of TCG TNC IF-IMC Specification 1.3
381 */
382 TNC_Result TNC_IMC_BatchEnding(TNC_IMCID imc_id,
383 TNC_ConnectionID connection_id)
384 {
385 if (!imc_scanner)
386 {
387 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
388 return TNC_RESULT_NOT_INITIALIZED;
389 }
390 return TNC_RESULT_SUCCESS;
391 }
392
393 /**
394 * see section 3.8.8 of TCG TNC IF-IMC Specification 1.3
395 */
396 TNC_Result TNC_IMC_Terminate(TNC_IMCID imc_id)
397 {
398 if (!imc_scanner)
399 {
400 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
401 return TNC_RESULT_NOT_INITIALIZED;
402 }
403 imc_scanner->destroy(imc_scanner);
404 imc_scanner = NULL;
405
406 return TNC_RESULT_SUCCESS;
407 }
408
409 /**
410 * see section 4.2.8.1 of TCG TNC IF-IMC Specification 1.3
411 */
412 TNC_Result TNC_IMC_ProvideBindFunction(TNC_IMCID imc_id,
413 TNC_TNCC_BindFunctionPointer bind_function)
414 {
415 if (!imc_scanner)
416 {
417 DBG1(DBG_IMC, "IMC \"%s\" has not been initialized", imc_name);
418 return TNC_RESULT_NOT_INITIALIZED;
419 }
420 return imc_scanner->bind_functions(imc_scanner, bind_function);
421 }