summaryrefslogtreecommitdiff
path: root/src/charon/daemon.c
blob: 62e29b365f6f120d2b7438efe5838965530a2012 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
/**
 * @file daemon.c
 * 
 * @brief Implementation of daemon_t and main of IKEv2-Daemon.
 * 
 */

/*
 * Copyright (C) 2006 Tobias Brunner, Daniel Roethlisberger
 * Copyright (C) 2005-2006 Martin Willi
 * Copyright (C) 2005 Jan Hutter
 * Hochschule fuer Technik Rapperswil
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 */

#include <stdio.h>
#include <linux/capability.h>
#include <sys/prctl.h>
#include <signal.h>
#include <pthread.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <time.h>
#include <string.h>
#include <getopt.h>
#include <errno.h>
#ifdef HAVE_BACKTRACE
# include <execinfo.h>
#endif /* HAVE_BACKTRACE */

#include "daemon.h"

#include <library.h>
#include <crypto/ca.h>
#include <utils/fetcher.h>
#include <config/credentials/local_credential_store.h>
#include <config/backends/local_backend.h>
#include <sa/authenticators/eap/eap_method.h>

/* on some distros, a capset definition is missing */
#ifdef NO_CAPSET_DEFINED
extern int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
#endif /* NO_CAPSET_DEFINED */

typedef struct private_daemon_t private_daemon_t;

/**
 * Private additions to daemon_t, contains threads and internal functions.
 */
struct private_daemon_t {
	/**
	 * Public members of daemon_t.
	 */
	daemon_t public;
	
	/**
	 * Signal set used for signal handling.
	 */
	sigset_t signal_set;
	
	/** 
	 * The thread_id of main-thread.
	 */
	pthread_t main_thread_id;
};

/**
 * One and only instance of the daemon.
 */
daemon_t *charon;

/**
 * hook in library for debugging messages
 */
extern void (*dbg) (int level, char *fmt, ...);

/**
 * Logging hook for library logs, spreads debug message over bus
 */
static void dbg_bus(int level, char *fmt, ...)
{
	va_list args;
	
	va_start(args, fmt);
	charon->bus->vsignal(charon->bus, DBG_LIB, level, fmt, args);
	va_end(args);
}

/**
 * Logging hook for library logs, using stderr output
 */
static void dbg_stderr(int level, char *fmt, ...)
{
	va_list args;
	
	va_start(args, fmt);
	fprintf(stderr, "00[LIB] ");
	vfprintf(stderr, fmt, args);
	fprintf(stderr, "\n");
	va_end(args);
}

/**
 * Run the daemon and handle unix signals
 */
static void run(private_daemon_t *this)
{
	/* reselect signals for this thread */
	sigemptyset(&(this->signal_set));
	sigaddset(&(this->signal_set), SIGINT); 
	sigaddset(&(this->signal_set), SIGHUP); 
	sigaddset(&(this->signal_set), SIGTERM); 
	pthread_sigmask(SIG_BLOCK, &(this->signal_set), 0);
	
	while(TRUE)
	{
		int signal_number;
		int error;
		
		error = sigwait(&(this->signal_set), &signal_number);
		if(error)
		{
			DBG1(DBG_DMN, "error %d while waiting for a signal", error);
			return;
		}
		switch (signal_number)
		{
			case SIGHUP:
			{
				DBG1(DBG_DMN, "signal of type SIGHUP received. Ignored");
				break;
			}
			case SIGINT:
			{
				DBG1(DBG_DMN, "signal of type SIGINT received. Shutting down");
				return;
			}
			case SIGTERM:
				DBG1(DBG_DMN, "signal of type SIGTERM received. Shutting down");
				return;
			default:
			{
				DBG1(DBG_DMN, "unknown signal %d received. Ignored", signal_number);
				break;
			}
		}
	}
}

/**
 * Clean up all daemon resources
 */
static void destroy(private_daemon_t *this)
{
	/* destruction is a non trivial task, we need to follow 
	* a strict order to prevent threading issues! 
	* Kill active threads first, except the sender, as
	* the killed IKE_SA want to send delete messages.
	*/
	/* we don't want to receive anything anymore... */
	DESTROY_IF(this->public.receiver);
	/* ignore all incoming user requests */
	DESTROY_IF(this->public.interfaces);
	/* stop scheduing jobs */
	DESTROY_IF(this->public.scheduler);
	/* stop processing jobs */
	DESTROY_IF(this->public.thread_pool);
	/* shut down manager with all IKE SAs */
	DESTROY_IF(this->public.ike_sa_manager);
	/* all child SAs should be down now, so kill kernel interface */
	DESTROY_IF(this->public.kernel_interface);
	/* destroy other infrastructure */
	DESTROY_IF(this->public.job_queue);
	DESTROY_IF(this->public.event_queue);
	DESTROY_IF(this->public.credentials);
	DESTROY_IF(this->public.backends);
	/* we hope the sender could send the outstanding deletes, but 
	 * we shut down here at any cost */
	DESTROY_IF(this->public.sender);
	DESTROY_IF(this->public.socket);
	/* before destroying bus with its listeners, rehook library logs */
	dbg = dbg_stderr;
	DESTROY_IF(this->public.bus);
	DESTROY_IF(this->public.outlog);
	DESTROY_IF(this->public.syslog);
	DESTROY_IF(this->public.authlog);
	free(this);
}


/**
 * Enforce daemon shutdown, with a given reason to do so.
 */
static void kill_daemon(private_daemon_t *this, char *reason)
{
	/* we send SIGTERM, so the daemon can cleanly shut down */
	DBG1(DBG_DMN, "killing daemon: %s", reason);
	if (this->main_thread_id == pthread_self())
	{
		/* initialization failed, terminate daemon */
		destroy(this);
		unlink(PID_FILE);
		exit(-1);
	}
	else
	{
		DBG1(DBG_DMN, "sending SIGTERM to ourself");
		raise(SIGTERM);
		/* thread must die, since he produced a ciritcal failure and can't continue */
		pthread_exit(NULL);
	}
}

/**
 * drop daemon capabilities
 */
static void drop_capabilities(private_daemon_t *this, bool full)
{
	struct __user_cap_header_struct hdr;
	struct __user_cap_data_struct data;
	/* CAP_NET_ADMIN is needed to use netlink */
	u_int32_t keep = (1<<CAP_NET_ADMIN);
	
	if (full)
	{
#		if IPSEC_GID
			setgid(IPSEC_GID);
#		endif
#		if IPSEC_UID
			setuid(IPSEC_UID);
#		endif
	}
	else
	{
		/* CAP_NET_BIND_SERVICE to bind services below port 1024, 
		 * CAP_NET_RAW to create RAW sockets.
		 * CAP_DAC_READ_SEARCH is needed to read ipsec.secrets */
		keep |= (1<<CAP_NET_BIND_SERVICE);
		keep |= (1<<CAP_NET_RAW);
		keep |= (1<<CAP_DAC_READ_SEARCH);
	}

	hdr.version = _LINUX_CAPABILITY_VERSION;
	hdr.pid = 0;
	data.effective = data.permitted = keep;
	data.inheritable = 0;
	
	if (capset(&hdr, &data))
	{
		kill_daemon(this, "unable to drop threads capabilities");
	}
}

/**
 * Initialize the daemon, optional with a strict crl policy
 */
static void initialize(private_daemon_t *this, bool syslog, level_t levels[])
{
	credential_store_t* credentials;
	signal_t signal;
	
	/* for uncritical pseudo random numbers */
	srandom(time(NULL) + getpid());
	
	/* setup bus and it's listeners first to enable log output */
	this->public.bus = bus_create();
	this->public.outlog = file_logger_create(stdout);
	this->public.syslog = sys_logger_create(LOG_DAEMON);
	this->public.authlog = sys_logger_create(LOG_AUTHPRIV);
	this->public.bus->add_listener(this->public.bus, &this->public.syslog->listener);
	this->public.bus->add_listener(this->public.bus, &this->public.outlog->listener);
	this->public.bus->add_listener(this->public.bus, &this->public.authlog->listener);
	this->public.authlog->set_level(this->public.authlog, SIG_ANY, LEVEL_AUDIT);
	/* set up hook to log dbg message in library via charons message bus */
	dbg = dbg_bus;
	
	/* apply loglevels */
	for (signal = 0; signal < DBG_MAX; signal++)
	{
		this->public.syslog->set_level(this->public.syslog,
									   signal, levels[signal]);
		if (!syslog)
		{
			this->public.outlog->set_level(this->public.outlog,
										   signal, levels[signal]);
		}
	}
	
	DBG1(DBG_DMN, "starting charon (strongSwan Version %s)", VERSION);
	
	this->public.socket = socket_create(IKEV2_UDP_PORT, IKEV2_NATT_PORT);
	this->public.ike_sa_manager = ike_sa_manager_create();
	this->public.job_queue = job_queue_create();
	this->public.event_queue = event_queue_create();
	this->public.credentials = (credential_store_t*)local_credential_store_create();
	this->public.backends = backend_manager_create();

	/* initialize fetcher_t class */
	fetcher_initialize();

	/* load secrets, ca certificates and crls */
	credentials = this->public.credentials;
	credentials->load_ca_certificates(credentials);
	credentials->load_aa_certificates(credentials);
	credentials->load_attr_certificates(credentials);
	credentials->load_ocsp_certificates(credentials);
	credentials->load_crls(credentials);
	credentials->load_secrets(credentials);
	
	/* start building threads, we are multi-threaded NOW */
	this->public.interfaces = interface_manager_create();
	this->public.sender = sender_create();
	this->public.receiver = receiver_create();
	this->public.scheduler = scheduler_create();
	this->public.kernel_interface = kernel_interface_create();
	this->public.thread_pool = thread_pool_create(NUMBER_OF_WORKING_THREADS);
}

/**
 * Handle SIGSEGV/SIGILL signals raised by threads
 */
void signal_handler(int signal)
{
#ifdef HAVE_BACKTRACE
	void *array[20];
	size_t size;
	char **strings;
	size_t i;

	size = backtrace(array, 20);
	strings = backtrace_symbols(array, size);

	DBG1(DBG_DMN, "thread %u received %s. Dumping %d frames from stack:",
		 pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL", size);

	for (i = 0; i < size; i++)
	{
		DBG1(DBG_DMN, "    %s", strings[i]);
	}
	free (strings);
#else /* !HAVE_BACKTRACE */
	DBG1(DBG_DMN, "thread %u received %s",
		 pthread_self(), signal == SIGSEGV ? "SIGSEGV" : "SIGILL");
#endif /* HAVE_BACKTRACE */
	DBG1(DBG_DMN, "killing ourself hard after SIGSEGV");
	raise(SIGKILL);
}

/**
 * Create the daemon.
 */
private_daemon_t *daemon_create(void)
{	
	private_daemon_t *this = malloc_thing(private_daemon_t);
	struct sigaction action;
		
	/* assign methods */
	this->public.kill = (void (*) (daemon_t*,char*))kill_daemon;
	this->public.drop_capabilities = (void(*)(daemon_t*,bool))drop_capabilities;
	
	/* NULL members for clean destruction */
	this->public.socket = NULL;
	this->public.ike_sa_manager = NULL;
	this->public.job_queue = NULL;
	this->public.event_queue = NULL;
	this->public.credentials = NULL;
	this->public.backends = NULL;
	this->public.sender= NULL;
	this->public.receiver = NULL;
	this->public.scheduler = NULL;
	this->public.kernel_interface = NULL;
	this->public.thread_pool = NULL;
	this->public.interfaces = NULL;
	this->public.bus = NULL;
	this->public.outlog = NULL;
	this->public.syslog = NULL;
	this->public.authlog = NULL;
	
	this->main_thread_id = pthread_self();
	
	/* setup signal handling for all threads */
	sigemptyset(&(this->signal_set));
	sigaddset(&(this->signal_set), SIGSEGV);
	sigaddset(&(this->signal_set), SIGINT); 
	sigaddset(&(this->signal_set), SIGHUP); 
	sigaddset(&(this->signal_set), SIGTERM); 
	pthread_sigmask(SIG_BLOCK, &(this->signal_set), 0);
	
	/* setup SIGSEGV handler for all threads */
	action.sa_handler = signal_handler;
	action.sa_mask = this->signal_set;
	action.sa_flags = 0;
	sigaction(SIGSEGV, &action, NULL);
	sigaction(SIGILL, &action, NULL);
	return this;
}

/**
 * print command line usage and exit
 */
static void usage(const char *msg)
{
	if (msg != NULL && *msg != '\0')
	{
		fprintf(stderr, "%s\n", msg);
	}
	fprintf(stderr, "Usage: charon\n"
					"         [--help]\n"
					"         [--version]\n"
					"         [--strictcrlpolicy]\n"
					"         [--cachecrls]\n"
					"         [--crlcheckinterval <interval>]\n"
					"         [--eapdir <dir>]\n"
					"         [--use-syslog]\n"
					"         [--debug-<type> <level>]\n"
					"           <type>:  log context type (dmn|mgr|ike|chd|job|cfg|knl|net|enc|lib)\n"
					"           <level>: log verbosity (-1 = silent, 0 = audit, 1 = control,\n"
					"                                    2 = controlmore, 3 = raw, 4 = private)\n"
					"\n"
		   );
	exit(msg == NULL? 0 : 1);
}

/**
 * Main function, manages the daemon.
 */
int main(int argc, char *argv[])
{
	u_int crl_check_interval = 0;
	strict_t strict_crl_policy = STRICT_NO;
	bool cache_crls = FALSE;
	bool use_syslog = FALSE;
	char *eapdir = IPSEC_EAPDIR;

	private_daemon_t *private_charon;
	FILE *pid_file;
	struct stat stb;
	linked_list_t *list;
	host_t *host;
	level_t levels[DBG_MAX];
	int signal;
	
	prctl(PR_SET_KEEPCAPS, 1);
	
	/* drop the capabilities we won't need at all */
	drop_capabilities(NULL, FALSE);
	
	/* use CTRL loglevel for default */
	for (signal = 0; signal < DBG_MAX; signal++)
	{
		levels[signal] = LEVEL_CTRL;
	}
	
	/* handle arguments */
	for (;;)
	{
		struct option long_opts[] = {
			{ "help", no_argument, NULL, 'h' },
			{ "version", no_argument, NULL, 'v' },
			{ "use-syslog", no_argument, NULL, 'l' },
			{ "strictcrlpolicy", required_argument, NULL, 'r' },
			{ "cachecrls", no_argument, NULL, 'C' },
			{ "crlcheckinterval", required_argument, NULL, 'x' },
			{ "eapdir", required_argument, NULL, 'e' },
			/* TODO: handle "debug-all" */
			{ "debug-dmn", required_argument, &signal, DBG_DMN },
			{ "debug-mgr", required_argument, &signal, DBG_MGR },
			{ "debug-ike", required_argument, &signal, DBG_IKE },
			{ "debug-chd", required_argument, &signal, DBG_CHD },
			{ "debug-job", required_argument, &signal, DBG_JOB },
			{ "debug-cfg", required_argument, &signal, DBG_CFG },
			{ "debug-knl", required_argument, &signal, DBG_KNL },
			{ "debug-net", required_argument, &signal, DBG_NET },
			{ "debug-enc", required_argument, &signal, DBG_ENC },
			{ "debug-lib", required_argument, &signal, DBG_LIB },
			{ 0,0,0,0 }
		};
		
		int c = getopt_long(argc, argv, "", long_opts, NULL);
		switch (c)
		{
			case EOF:
	    		break;
			case 'h':
				usage(NULL);
				break;
			case 'v':
				printf("Linux strongSwan %s\n", VERSION);
				exit(0);
			case 'l':
				use_syslog = TRUE;
				continue;
			case 'r':
				strict_crl_policy = atoi(optarg);
				continue;
			case 'C':
				cache_crls = TRUE;
				continue;
			case 'x':
				crl_check_interval = atoi(optarg);
				continue;
			case 'e':
				eapdir = optarg;
				continue;
			case 0:
				/* option is in signal */
				levels[signal] = atoi(optarg);
				continue;
			default:
				usage("");
				break;
		}
		break;
	}

	private_charon = daemon_create();
	charon = (daemon_t*)private_charon;
	
	/* initialize daemon */
	initialize(private_charon, use_syslog, levels);

	/* load pluggable EAP modules */
	eap_method_load(eapdir);
	
	/* set strict_crl_policy, cache_crls and crl_check_interval options */
	ca_info_set_options(strict_crl_policy, cache_crls, crl_check_interval);

	/* check/setup PID file */
	if (stat(PID_FILE, &stb) == 0)
	{
		DBG1(DBG_DMN, "charon already running (\""PID_FILE"\" exists)");
		destroy(private_charon);
		exit(-1);
	}
	pid_file = fopen(PID_FILE, "w");
	if (pid_file)
	{
		fprintf(pid_file, "%d\n", getpid());
		fclose(pid_file);
	}
	
	/* log socket info */
	list = charon->kernel_interface->create_address_list(charon->kernel_interface);
	DBG1(DBG_NET, "listening on %d addresses:", list->get_count(list));
	while (list->remove_first(list, (void**)&host) == SUCCESS)
	{
		DBG1(DBG_NET, "  %H", host);
		host->destroy(host);
	}
	list->destroy(list);
	
	/* drop additional capabilites (bind & root) */
	drop_capabilities(private_charon, TRUE);
	
	/* run daemon */
	run(private_charon);
	
	eap_method_unload();
	fetcher_finalize();
	/* normal termination, cleanup and exit */
	destroy(private_charon);
	unlink(PID_FILE);
	
	return 0;
}