xref: /freebsd/contrib/ntp/libntp/lib/isc/unix/net.c (revision 535af610) 
1 /*
2  * Copyright (C) 2004, 2005, 2007, 2008, 2012  Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (C) 1999-2003  Internet Software Consortium.
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15  * PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* $Id$ */
19 
20 #include <config.h>
21 
22 #include <sys/types.h>
23 
24 #if defined(HAVE_SYS_SYSCTL_H)
25 #if defined(HAVE_SYS_PARAM_H)
26 #include <sys/param.h>
27 #endif
28 #include <sys/sysctl.h>
29 #endif
30 
31 #include <errno.h>
32 #include <unistd.h>
33 
34 #include <isc/log.h>
35 #include <isc/msgs.h>
36 #include <isc/net.h>
37 #include <isc/once.h>
38 #include <isc/strerror.h>
39 #include <isc/string.h>
40 #include <isc/util.h>
41 
42 /*%
43  * Definitions about UDP port range specification.  This is a total mess of
44  * portability variants: some use sysctl (but the sysctl names vary), some use
45  * system-specific interfaces, some have the same interface for IPv4 and IPv6,
46  * some separate them, etc...
47  */
48 
49 /*%
50  * The last resort defaults: use all non well known port space
51  */
52 #ifndef ISC_NET_PORTRANGELOW
53 #define ISC_NET_PORTRANGELOW 1024
54 #endif	/* ISC_NET_PORTRANGELOW */
55 #ifndef ISC_NET_PORTRANGEHIGH
56 #define ISC_NET_PORTRANGEHIGH 65535
57 #endif	/* ISC_NET_PORTRANGEHIGH */
58 
59 #ifdef HAVE_SYSCTLBYNAME
60 
61 /*%
62  * sysctl variants
63  */
64 #if defined(__FreeBSD__) || defined(__APPLE__) || defined(__DragonFly__)
65 #define USE_SYSCTL_PORTRANGE
66 #define SYSCTL_V4PORTRANGE_LOW	"net.inet.ip.portrange.hifirst"
67 #define SYSCTL_V4PORTRANGE_HIGH	"net.inet.ip.portrange.hilast"
68 #define SYSCTL_V6PORTRANGE_LOW	"net.inet.ip.portrange.hifirst"
69 #define SYSCTL_V6PORTRANGE_HIGH	"net.inet.ip.portrange.hilast"
70 #endif
71 
72 #ifdef __NetBSD__
73 #define USE_SYSCTL_PORTRANGE
74 #define SYSCTL_V4PORTRANGE_LOW	"net.inet.ip.anonportmin"
75 #define SYSCTL_V4PORTRANGE_HIGH	"net.inet.ip.anonportmax"
76 #define SYSCTL_V6PORTRANGE_LOW	"net.inet6.ip6.anonportmin"
77 #define SYSCTL_V6PORTRANGE_HIGH	"net.inet6.ip6.anonportmax"
78 #endif
79 
80 #else /* !HAVE_SYSCTLBYNAME */
81 
82 #ifdef __OpenBSD__
83 #define USE_SYSCTL_PORTRANGE
84 #define SYSCTL_V4PORTRANGE_LOW	{ CTL_NET, PF_INET, IPPROTO_IP, \
85 				  IPCTL_IPPORT_HIFIRSTAUTO }
86 #define SYSCTL_V4PORTRANGE_HIGH	{ CTL_NET, PF_INET, IPPROTO_IP, \
87 				  IPCTL_IPPORT_HILASTAUTO }
88 /* Same for IPv6 */
89 #define SYSCTL_V6PORTRANGE_LOW	SYSCTL_V4PORTRANGE_LOW
90 #define SYSCTL_V6PORTRANGE_HIGH	SYSCTL_V4PORTRANGE_HIGH
91 #endif
92 
93 #endif /* HAVE_SYSCTLBYNAME */
94 
95 #if defined(ISC_PLATFORM_NEEDIN6ADDRANY)
96 const struct in6_addr isc_net_in6addrany = IN6ADDR_ANY_INIT;
97 #endif
98 
99 #if defined(ISC_PLATFORM_HAVEIPV6)
100 
101 # if defined(ISC_PLATFORM_NEEDIN6ADDRLOOPBACK)
102 const struct in6_addr isc_net_in6addrloop = IN6ADDR_LOOPBACK_INIT;
103 # endif
104 
105 # if defined(WANT_IPV6)
106 static isc_once_t 	once_ipv6only = ISC_ONCE_INIT;
107 # endif
108 
109 # if defined(ISC_PLATFORM_HAVEIPV6) && \
110      defined(WANT_IPV6) && defined(ISC_PLATFORM_HAVEIN6PKTINFO)
111 static isc_once_t 	once_ipv6pktinfo = ISC_ONCE_INIT;
112 # endif
113 #endif /* ISC_PLATFORM_HAVEIPV6 */
114 
115 static isc_once_t 	once = ISC_ONCE_INIT;
116 
117 static isc_result_t	ipv4_result = ISC_R_NOTFOUND;
118 static isc_result_t	ipv6_result = ISC_R_NOTFOUND;
119 static isc_result_t	unix_result = ISC_R_NOTFOUND;
120 static isc_result_t	ipv6only_result = ISC_R_NOTFOUND;
121 static isc_result_t	ipv6pktinfo_result = ISC_R_NOTFOUND;
122 
123 static isc_result_t
124 try_proto(int domain) {
125 	int s;
126 	isc_result_t result = ISC_R_SUCCESS;
127 	char strbuf[ISC_STRERRORSIZE];
128 
129 	s = socket(domain, SOCK_STREAM, 0);
130 	if (s == -1) {
131 		switch (errno) {
132 #ifdef EAFNOSUPPORT
133 		case EAFNOSUPPORT:
134 #endif
135 #ifdef EPROTONOSUPPORT
136 		case EPROTONOSUPPORT:
137 #endif
138 #ifdef EINVAL
139 		case EINVAL:
140 #endif
141 			return (ISC_R_NOTFOUND);
142 		default:
143 			isc__strerror(errno, strbuf, sizeof(strbuf));
144 			UNEXPECTED_ERROR(__FILE__, __LINE__,
145 					 "socket() %s: %s",
146 					 isc_msgcat_get(isc_msgcat,
147 							ISC_MSGSET_GENERAL,
148 							ISC_MSG_FAILED,
149 							"failed"),
150 					 strbuf);
151 			return (ISC_R_UNEXPECTED);
152 		}
153 	}
154 
155 #ifdef ISC_PLATFORM_HAVEIPV6
156 #ifdef WANT_IPV6
157 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
158 	if (domain == PF_INET6) {
159 		struct sockaddr_in6 sin6;
160 		GETSOCKNAME_SOCKLEN_TYPE len;	/* NTP local change */
161 
162 		/*
163 		 * Check to see if IPv6 is broken, as is common on Linux.
164 		 */
165 		len = sizeof(sin6);
166 		if (getsockname(s, (struct sockaddr *)&sin6, &len) < 0)
167 		{
168 			isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
169 				      ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR,
170 				      "retrieving the address of an IPv6 "
171 				      "socket from the kernel failed.");
172 			isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL,
173 				      ISC_LOGMODULE_SOCKET, ISC_LOG_ERROR,
174 				      "IPv6 is not supported.");
175 			result = ISC_R_NOTFOUND;
176 		} else {
177 			if (len == sizeof(struct sockaddr_in6))
178 				result = ISC_R_SUCCESS;
179 			else {
180 				isc_log_write(isc_lctx,
181 					      ISC_LOGCATEGORY_GENERAL,
182 					      ISC_LOGMODULE_SOCKET,
183 					      ISC_LOG_ERROR,
184 					      "IPv6 structures in kernel and "
185 					      "user space do not match.");
186 				isc_log_write(isc_lctx,
187 					      ISC_LOGCATEGORY_GENERAL,
188 					      ISC_LOGMODULE_SOCKET,
189 					      ISC_LOG_ERROR,
190 					      "IPv6 is not supported.");
191 				result = ISC_R_NOTFOUND;
192 			}
193 		}
194 	}
195 #endif
196 #endif
197 #endif
198 
199 	(void)close(s);
200 
201 	return (result);
202 }
203 
204 static void
205 initialize_action(void) {
206 	ipv4_result = try_proto(PF_INET);
207 #ifdef ISC_PLATFORM_HAVEIPV6
208 #ifdef WANT_IPV6
209 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
210 	ipv6_result = try_proto(PF_INET6);
211 #endif
212 #endif
213 #endif
214 #ifdef ISC_PLATFORM_HAVESYSUNH
215 	unix_result = try_proto(PF_UNIX);
216 #endif
217 }
218 
219 static void
220 initialize(void) {
221 	RUNTIME_CHECK(isc_once_do(&once, initialize_action) == ISC_R_SUCCESS);
222 }
223 
224 isc_result_t
225 isc_net_probeipv4(void) {
226 	initialize();
227 	return (ipv4_result);
228 }
229 
230 isc_result_t
231 isc_net_probeipv6(void) {
232 	initialize();
233 	return (ipv6_result);
234 }
235 
236 isc_result_t
237 isc_net_probeunix(void) {
238 	initialize();
239 	return (unix_result);
240 }
241 
242 #ifdef ISC_PLATFORM_HAVEIPV6
243 #ifdef WANT_IPV6
244 static void
245 try_ipv6only(void) {
246 #ifdef IPV6_V6ONLY
247 	int s, on;
248 	char strbuf[ISC_STRERRORSIZE];
249 #endif
250 	isc_result_t result;
251 
252 	result = isc_net_probeipv6();
253 	if (result != ISC_R_SUCCESS) {
254 		ipv6only_result = result;
255 		return;
256 	}
257 
258 #ifndef IPV6_V6ONLY
259 	ipv6only_result = ISC_R_NOTFOUND;
260 	return;
261 #else
262 	/* check for TCP sockets */
263 	s = socket(PF_INET6, SOCK_STREAM, 0);
264 	if (s == -1) {
265 		isc__strerror(errno, strbuf, sizeof(strbuf));
266 		UNEXPECTED_ERROR(__FILE__, __LINE__,
267 				 "socket() %s: %s",
268 				 isc_msgcat_get(isc_msgcat,
269 						ISC_MSGSET_GENERAL,
270 						ISC_MSG_FAILED,
271 						"failed"),
272 				 strbuf);
273 		ipv6only_result = ISC_R_UNEXPECTED;
274 		return;
275 	}
276 
277 	on = 1;
278 	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
279 		ipv6only_result = ISC_R_NOTFOUND;
280 		goto close;
281 	}
282 
283 	close(s);
284 
285 	/* check for UDP sockets */
286 	s = socket(PF_INET6, SOCK_DGRAM, 0);
287 	if (s == -1) {
288 		isc__strerror(errno, strbuf, sizeof(strbuf));
289 		UNEXPECTED_ERROR(__FILE__, __LINE__,
290 				 "socket() %s: %s",
291 				 isc_msgcat_get(isc_msgcat,
292 						ISC_MSGSET_GENERAL,
293 						ISC_MSG_FAILED,
294 						"failed"),
295 				 strbuf);
296 		ipv6only_result = ISC_R_UNEXPECTED;
297 		return;
298 	}
299 
300 	on = 1;
301 	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
302 		ipv6only_result = ISC_R_NOTFOUND;
303 		goto close;
304 	}
305 
306 	ipv6only_result = ISC_R_SUCCESS;
307 
308 close:
309 	close(s);
310 	return;
311 #endif /* IPV6_V6ONLY */
312 }
313 
314 static void
315 initialize_ipv6only(void) {
316 	RUNTIME_CHECK(isc_once_do(&once_ipv6only,
317 				  try_ipv6only) == ISC_R_SUCCESS);
318 }
319 
320 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
321 static void
322 try_ipv6pktinfo(void) {
323 	int s, on;
324 	char strbuf[ISC_STRERRORSIZE];
325 	isc_result_t result;
326 	int optname;
327 
328 	result = isc_net_probeipv6();
329 	if (result != ISC_R_SUCCESS) {
330 		ipv6pktinfo_result = result;
331 		return;
332 	}
333 
334 	/* we only use this for UDP sockets */
335 	s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
336 	if (s == -1) {
337 		isc__strerror(errno, strbuf, sizeof(strbuf));
338 		UNEXPECTED_ERROR(__FILE__, __LINE__,
339 				 "socket() %s: %s",
340 				 isc_msgcat_get(isc_msgcat,
341 						ISC_MSGSET_GENERAL,
342 						ISC_MSG_FAILED,
343 						"failed"),
344 				 strbuf);
345 		ipv6pktinfo_result = ISC_R_UNEXPECTED;
346 		return;
347 	}
348 
349 #ifdef IPV6_RECVPKTINFO
350 	optname = IPV6_RECVPKTINFO;
351 #else
352 	optname = IPV6_PKTINFO;
353 #endif
354 	on = 1;
355 	if (setsockopt(s, IPPROTO_IPV6, optname, &on, sizeof(on)) < 0) {
356 		ipv6pktinfo_result = ISC_R_NOTFOUND;
357 		goto close;
358 	}
359 
360 	ipv6pktinfo_result = ISC_R_SUCCESS;
361 
362 close:
363 	close(s);
364 	return;
365 }
366 
367 static void
368 initialize_ipv6pktinfo(void) {
369 	RUNTIME_CHECK(isc_once_do(&once_ipv6pktinfo,
370 				  try_ipv6pktinfo) == ISC_R_SUCCESS);
371 }
372 #endif /* ISC_PLATFORM_HAVEIN6PKTINFO */
373 #endif /* WANT_IPV6 */
374 #endif /* ISC_PLATFORM_HAVEIPV6 */
375 
376 isc_result_t
377 isc_net_probe_ipv6only(void) {
378 #ifdef ISC_PLATFORM_HAVEIPV6
379 #ifdef WANT_IPV6
380 	initialize_ipv6only();
381 #else
382 	ipv6only_result = ISC_R_NOTFOUND;
383 #endif
384 #endif
385 	return (ipv6only_result);
386 }
387 
388 isc_result_t
389 isc_net_probe_ipv6pktinfo(void) {
390 #ifdef ISC_PLATFORM_HAVEIPV6
391 #ifdef ISC_PLATFORM_HAVEIN6PKTINFO
392 #ifdef WANT_IPV6
393 	initialize_ipv6pktinfo();
394 #else
395 	ipv6pktinfo_result = ISC_R_NOTFOUND;
396 #endif
397 #endif
398 #endif
399 	return (ipv6pktinfo_result);
400 }
401 
402 #if defined(USE_SYSCTL_PORTRANGE)
403 #if defined(HAVE_SYSCTLBYNAME)
404 static isc_result_t
405 getudpportrange_sysctl(int af, in_port_t *low, in_port_t *high) {
406 	int port_low, port_high;
407 	size_t portlen;
408 	const char *sysctlname_lowport, *sysctlname_hiport;
409 
410 	if (af == AF_INET) {
411 		sysctlname_lowport = SYSCTL_V4PORTRANGE_LOW;
412 		sysctlname_hiport = SYSCTL_V4PORTRANGE_HIGH;
413 	} else {
414 		sysctlname_lowport = SYSCTL_V6PORTRANGE_LOW;
415 		sysctlname_hiport = SYSCTL_V6PORTRANGE_HIGH;
416 	}
417 	portlen = sizeof(portlen);
418 	if (sysctlbyname(sysctlname_lowport, &port_low, &portlen,
419 			 NULL, 0) < 0) {
420 		return (ISC_R_FAILURE);
421 	}
422 	portlen = sizeof(portlen);
423 	if (sysctlbyname(sysctlname_hiport, &port_high, &portlen,
424 			 NULL, 0) < 0) {
425 		return (ISC_R_FAILURE);
426 	}
427 	if ((port_low & ~0xffff) != 0 || (port_high & ~0xffff) != 0)
428 		return (ISC_R_RANGE);
429 
430 	*low = (in_port_t)port_low;
431 	*high = (in_port_t)port_high;
432 
433 	return (ISC_R_SUCCESS);
434 }
435 #else /* !HAVE_SYSCTLBYNAME */
436 static isc_result_t
437 getudpportrange_sysctl(int af, in_port_t *low, in_port_t *high) {
438 	int mib_lo4[4] = SYSCTL_V4PORTRANGE_LOW;
439 	int mib_hi4[4] = SYSCTL_V4PORTRANGE_HIGH;
440 	int mib_lo6[4] = SYSCTL_V6PORTRANGE_LOW;
441 	int mib_hi6[4] = SYSCTL_V6PORTRANGE_HIGH;
442 	int *mib_lo, *mib_hi, miblen;
443 	int port_low, port_high;
444 	size_t portlen;
445 
446 	if (af == AF_INET) {
447 		mib_lo = mib_lo4;
448 		mib_hi = mib_hi4;
449 		miblen = sizeof(mib_lo4) / sizeof(mib_lo4[0]);
450 	} else {
451 		mib_lo = mib_lo6;
452 		mib_hi = mib_hi6;
453 		miblen = sizeof(mib_lo6) / sizeof(mib_lo6[0]);
454 	}
455 
456 	portlen = sizeof(portlen);
457 	if (sysctl(mib_lo, miblen, &port_low, &portlen, NULL, 0) < 0) {
458 		return (ISC_R_FAILURE);
459 	}
460 
461 	portlen = sizeof(portlen);
462 	if (sysctl(mib_hi, miblen, &port_high, &portlen, NULL, 0) < 0) {
463 		return (ISC_R_FAILURE);
464 	}
465 
466 	if ((port_low & ~0xffff) != 0 || (port_high & ~0xffff) != 0)
467 		return (ISC_R_RANGE);
468 
469 	*low = (in_port_t) port_low;
470 	*high = (in_port_t) port_high;
471 
472 	return (ISC_R_SUCCESS);
473 }
474 #endif /* HAVE_SYSCTLBYNAME */
475 #endif /* USE_SYSCTL_PORTRANGE */
476 
477 isc_result_t
478 isc_net_getudpportrange(int af, in_port_t *low, in_port_t *high) {
479 	int result = ISC_R_FAILURE;
480 
481 	REQUIRE(low != NULL && high != NULL);
482 
483 #if defined(USE_SYSCTL_PORTRANGE)
484 	result = getudpportrange_sysctl(af, low, high);
485 #else
486 	UNUSED(af);
487 #endif
488 
489 	if (result != ISC_R_SUCCESS) {
490 		*low = ISC_NET_PORTRANGELOW;
491 		*high = ISC_NET_PORTRANGEHIGH;
492 	}
493 
494 	return (ISC_R_SUCCESS);	/* we currently never fail in this function */
495 }
496 
497 void
498 isc_net_disableipv4(void) {
499 	initialize();
500 	if (ipv4_result == ISC_R_SUCCESS)
501 		ipv4_result = ISC_R_DISABLED;
502 }
503 
504 void
505 isc_net_disableipv6(void) {
506 	initialize();
507 	if (ipv6_result == ISC_R_SUCCESS)
508 		ipv6_result = ISC_R_DISABLED;
509 }
510 
511 void
512 isc_net_enableipv4(void) {
513 	initialize();
514 	if (ipv4_result == ISC_R_DISABLED)
515 		ipv4_result = ISC_R_SUCCESS;
516 }
517 
518 void
519 isc_net_enableipv6(void) {
520 	initialize();
521 	if (ipv6_result == ISC_R_DISABLED)
522 		ipv6_result = ISC_R_SUCCESS;
523 }
524