/contrib/ntp/libisc/net.c

  1/*
  2 * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 1999-2003  Internet Software Consortium.
  4 *
  5 * Permission to use, copy, modify, and 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: net.c,v 1.22.2.2.10.7 2004/04/29 01:31:22 marka Exp $ */
 19
 20#include <config.h>
 21
 22#include <errno.h>
 23#include <unistd.h>
 24
 25#include <isc/net.h>
 26#include <isc/once.h>
 27#include <isc/strerror.h>
 28#include <isc/string.h>
 29#include <isc/util.h>
 30
 31#if defined(ISC_PLATFORM_HAVEIPV6) && defined(ISC_PLATFORM_NEEDIN6ADDRANY)
 32const struct in6_addr isc_net_in6addrany = IN6ADDR_ANY_INIT;
 33#endif
 34
 35#if defined(ISC_PLATFORM_HAVEIPV6) && defined(ISC_PLATFORM_NEEDIN6ADDRLOOPBACK)
 36const struct in6_addr isc_net_in6addrloop = IN6ADDR_LOOPBACK_INIT;
 37#endif
 38
 39static isc_boolean_t 	once = ISC_FALSE;
 40static isc_once_t 	once_ipv6only = ISC_ONCE_INIT;
 41static isc_once_t 	once_ipv6pktinfo = ISC_ONCE_INIT;
 42static isc_result_t	ipv4_result = ISC_R_NOTFOUND;
 43static isc_result_t	ipv6_result = ISC_R_NOTFOUND;
 44static isc_result_t	ipv6only_result = ISC_R_NOTFOUND;
 45static isc_result_t	ipv6pktinfo_result = ISC_R_NOTFOUND;
 46
 47static isc_result_t
 48try_proto(int domain) {
 49	int s;
 50	isc_result_t result = ISC_R_SUCCESS;
 51	char strbuf[ISC_STRERRORSIZE];
 52
 53	s = socket(domain, SOCK_STREAM, 0);
 54	if (s == -1) {
 55		switch (errno) {
 56#ifdef EAFNOSUPPORT
 57		case EAFNOSUPPORT:
 58#endif
 59#ifdef EPROTONOSUPPORT
 60		case EPROTONOSUPPORT:
 61#endif
 62#ifdef EINVAL
 63		case EINVAL:
 64#endif
 65			return (ISC_R_NOTFOUND);
 66		default:
 67			isc__strerror(errno, strbuf, sizeof(strbuf));
 68			UNEXPECTED_ERROR(__FILE__, __LINE__,
 69					 "socket() failed: %s",
 70					 strbuf);
 71			return (ISC_R_UNEXPECTED);
 72		}
 73	}
 74
 75#ifdef ISC_PLATFORM_HAVEIPV6
 76#ifdef WANT_IPV6
 77#ifdef ISC_PLATFORM_HAVEIN6PKTINFO
 78	if (domain == PF_INET6) {
 79		struct sockaddr_in6 sin6;
 80		GETSOCKNAME_SOCKLEN_TYPE len;
 81
 82		/*
 83		 * Check to see if IPv6 is broken, as is common on Linux.
 84		 */
 85		len = sizeof(sin6);
 86		if (getsockname(s, (struct sockaddr *)&sin6, &len) < 0)
 87		{
 88			result = ISC_R_NOTFOUND;
 89		} else {
 90			if (len == sizeof(struct sockaddr_in6))
 91				result = ISC_R_SUCCESS;
 92			else {
 93				result = ISC_R_NOTFOUND;
 94			}
 95		}
 96	}
 97#endif
 98#endif
 99#endif
100
101	(void)close(s);
102
103	return (result);
104}
105
106static void
107initialize_action(void) {
108	ipv4_result = try_proto(PF_INET);
109#ifdef ISC_PLATFORM_HAVEIPV6
110#ifdef WANT_IPV6
111#ifdef ISC_PLATFORM_HAVEIN6PKTINFO
112	ipv6_result = try_proto(PF_INET6);
113#endif
114#endif
115#endif
116}
117
118static void
119initialize(void) {
120	if(once == ISC_FALSE) {
121		initialize_action();
122		once = ISC_TRUE;
123	}
124}
125
126isc_result_t
127isc_net_probeipv4(void) {
128	initialize();
129	return (ipv4_result);
130}
131
132isc_result_t
133isc_net_probeipv6(void) {
134	initialize();
135	return (ipv6_result);
136}
137
138#ifdef ISC_PLATFORM_HAVEIPV6
139#ifdef WANT_IPV6
140static void
141try_ipv6only(void) {
142#ifdef IPV6_V6ONLY
143	int s, on;
144	char strbuf[ISC_STRERRORSIZE];
145#endif
146	isc_result_t result;
147
148	result = isc_net_probeipv6();
149	if (result != ISC_R_SUCCESS) {
150		ipv6only_result = result;
151		return;
152	}
153
154#ifndef IPV6_V6ONLY
155	ipv6only_result = ISC_R_NOTFOUND;
156	return;
157#else
158	/* check for TCP sockets */
159	s = socket(PF_INET6, SOCK_STREAM, 0);
160	if (s == -1) {
161		isc__strerror(errno, strbuf, sizeof(strbuf));
162		UNEXPECTED_ERROR(__FILE__, __LINE__,
163				 "socket() failed: %s",
164				 strbuf);
165		ipv6only_result = ISC_R_UNEXPECTED;
166		return;
167	}
168
169	on = 1;
170	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
171		ipv6only_result = ISC_R_NOTFOUND;
172		goto close;
173	}
174
175	close(s);
176
177	/* check for UDP sockets */
178	s = socket(PF_INET6, SOCK_DGRAM, 0);
179	if (s == -1) {
180		isc__strerror(errno, strbuf, sizeof(strbuf));
181		UNEXPECTED_ERROR(__FILE__, __LINE__,
182				 "socket() failed: %s",
183				 strbuf);
184		ipv6only_result = ISC_R_UNEXPECTED;
185		return;
186	}
187
188	on = 1;
189	if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0) {
190		ipv6only_result = ISC_R_NOTFOUND;
191		goto close;
192	}
193
194	close(s);
195
196	ipv6only_result = ISC_R_SUCCESS;
197
198close:
199	close(s);
200	return;
201#endif /* IPV6_V6ONLY */
202}
203
204static void
205initialize_ipv6only(void) {
206	RUNTIME_CHECK(isc_once_do(&once_ipv6only,
207				  try_ipv6only) == ISC_R_SUCCESS);
208}
209
210static void
211try_ipv6pktinfo(void) {
212	int s, on;
213	char strbuf[ISC_STRERRORSIZE];
214	isc_result_t result;
215	int optname;
216
217	result = isc_net_probeipv6();
218	if (result != ISC_R_SUCCESS) {
219		ipv6pktinfo_result = result;
220		return;
221	}
222
223	/* we only use this for UDP sockets */
224	s = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
225	if (s == -1) {
226		isc__strerror(errno, strbuf, sizeof(strbuf));
227		UNEXPECTED_ERROR(__FILE__, __LINE__,
228				 "socket() failed: %s",
229				 strbuf);
230		ipv6pktinfo_result = ISC_R_UNEXPECTED;
231		return;
232	}
233
234#ifdef IPV6_RECVPKTINFO
235	optname = IPV6_RECVPKTINFO;
236#else
237	optname = IPV6_PKTINFO;
238#endif
239	on = 1;
240	if (setsockopt(s, IPPROTO_IPV6, optname, &on, sizeof(on)) < 0) {
241		ipv6pktinfo_result = ISC_R_NOTFOUND;
242		goto close;
243	}
244
245	close(s);
246	ipv6pktinfo_result = ISC_R_SUCCESS;
247
248close:
249	close(s);
250	return;
251}
252
253static void
254initialize_ipv6pktinfo(void) {
255	RUNTIME_CHECK(isc_once_do(&once_ipv6pktinfo,
256				  try_ipv6pktinfo) == ISC_R_SUCCESS);
257}
258#endif /* WANT_IPV6 */
259#endif /* ISC_PLATFORM_HAVEIPV6 */
260
261isc_result_t
262isc_net_probe_ipv6only(void) {
263#ifdef ISC_PLATFORM_HAVEIPV6
264#ifdef WANT_IPV6
265	initialize_ipv6only();
266#else
267	ipv6only_result = ISC_R_NOTFOUND;
268#endif
269#endif
270	return (ipv6only_result);
271}
272
273isc_result_t
274isc_net_probe_ipv6pktinfo(void) {
275#ifdef ISC_PLATFORM_HAVEIPV6
276#ifdef WANT_IPV6
277	initialize_ipv6pktinfo();
278#else
279	ipv6pktinfo_result = ISC_R_NOTFOUND;
280#endif
281#endif
282	return (ipv6pktinfo_result);
283}
284
285void
286isc_net_disableipv4(void) {
287	initialize();
288	if (ipv4_result == ISC_R_SUCCESS)
289		ipv4_result = ISC_R_DISABLED;
290}
291
292void
293isc_net_disableipv6(void) {
294	initialize();
295	if (ipv6_result == ISC_R_SUCCESS)
296		ipv6_result = ISC_R_DISABLED;
297}
298
299void
300isc_net_enableipv4(void) {
301	initialize();
302	if (ipv4_result == ISC_R_DISABLED)
303		ipv4_result = ISC_R_SUCCESS;
304}
305
306void
307isc_net_enableipv6(void) {
308	initialize();
309	if (ipv6_result == ISC_R_DISABLED)
310		ipv6_result = ISC_R_SUCCESS;
311}