/contrib/ntp/libisc/ifiter_getifaddrs.c

  1/*
  2 * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
  3 * Copyright (C) 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: ifiter_getifaddrs.c,v 1.2.68.3 2004/03/06 08:14:59 marka Exp $ */
 19
 20/*
 21 * Obtain the list of network interfaces using the getifaddrs(3) library.
 22 */
 23
 24#include <ifaddrs.h>
 25
 26#define IFITER_MAGIC		ISC_MAGIC('I', 'F', 'I', 'G')
 27#define VALID_IFITER(t)		ISC_MAGIC_VALID(t, IFITER_MAGIC)
 28
 29struct isc_interfaceiter {
 30	unsigned int		magic;		/* Magic number. */
 31	isc_mem_t		*mctx;
 32	void			*buf;		/* (unused) */
 33	unsigned int		bufsize;	/* (always 0) */
 34	struct ifaddrs		*ifaddrs;	/* List of ifaddrs */
 35	struct ifaddrs		*pos;		/* Ptr to current ifaddr */
 36	isc_interface_t		current;	/* Current interface data. */
 37	isc_result_t		result;		/* Last result code. */
 38};
 39
 40isc_result_t
 41isc_interfaceiter_create(isc_mem_t *mctx, isc_interfaceiter_t **iterp) {
 42	isc_interfaceiter_t *iter;
 43	isc_result_t result;
 44	char strbuf[ISC_STRERRORSIZE];
 45
 46	REQUIRE(iterp != NULL);
 47	REQUIRE(*iterp == NULL);
 48
 49	iter = isc_mem_get(mctx, sizeof(*iter));
 50	if (iter == NULL)
 51		return (ISC_R_NOMEMORY);
 52
 53	iter->mctx = mctx;
 54	iter->buf = NULL;
 55	iter->bufsize = 0;
 56	iter->ifaddrs = NULL;
 57
 58	if (getifaddrs(&iter->ifaddrs) < 0) {
 59		isc__strerror(errno, strbuf, sizeof(strbuf));
 60		UNEXPECTED_ERROR(__FILE__, __LINE__,
 61				 isc_msgcat_get(isc_msgcat,
 62						ISC_MSGSET_IFITERGETIFADDRS,
 63						ISC_MSG_GETIFADDRS,
 64						"getting interface "
 65						"addresses: getifaddrs: %s"),
 66				 strbuf);
 67		result = ISC_R_UNEXPECTED;
 68		goto failure;
 69	}
 70
 71	/*
 72	 * A newly created iterator has an undefined position
 73	 * until isc_interfaceiter_first() is called.
 74	 */
 75	iter->pos = NULL;
 76	iter->result = ISC_R_FAILURE;
 77
 78	iter->magic = IFITER_MAGIC;
 79	*iterp = iter;
 80	return (ISC_R_SUCCESS);
 81
 82 failure:
 83	if (iter->ifaddrs != NULL) /* just in case */
 84		freeifaddrs(iter->ifaddrs);
 85	isc_mem_put(mctx, iter, sizeof(*iter));
 86	return (result);
 87}
 88
 89/*
 90 * Get information about the current interface to iter->current.
 91 * If successful, return ISC_R_SUCCESS.
 92 * If the interface has an unsupported address family,
 93 * return ISC_R_IGNORE.
 94 */
 95
 96static isc_result_t
 97internal_current(isc_interfaceiter_t *iter) {
 98	struct ifaddrs *ifa;
 99	int family;
100	unsigned int namelen;
101
102	REQUIRE(VALID_IFITER(iter));
103
104	ifa = iter->pos;
105
106	INSIST(ifa != NULL);
107	INSIST(ifa->ifa_name != NULL);
108	INSIST(ifa->ifa_addr != NULL);
109
110	family = ifa->ifa_addr->sa_family;
111	if (family != AF_INET && family != AF_INET6)
112		return (ISC_R_IGNORE);
113
114	memset(&iter->current, 0, sizeof(iter->current));
115
116	namelen = strlen(ifa->ifa_name);
117	if (namelen > sizeof(iter->current.name) - 1)
118		namelen = sizeof(iter->current.name) - 1;
119
120	memset(iter->current.name, 0, sizeof(iter->current.name));
121	memcpy(iter->current.name, ifa->ifa_name, namelen);
122
123	iter->current.flags = 0;
124
125	if ((ifa->ifa_flags & IFF_UP) != 0)
126		iter->current.flags |= INTERFACE_F_UP;
127
128	if ((ifa->ifa_flags & IFF_POINTOPOINT) != 0)
129		iter->current.flags |= INTERFACE_F_POINTTOPOINT;
130
131	if ((ifa->ifa_flags & IFF_LOOPBACK) != 0)
132		iter->current.flags |= INTERFACE_F_LOOPBACK;
133
134	if ((ifa->ifa_flags & IFF_BROADCAST) != 0) {
135		iter->current.flags |= INTERFACE_F_BROADCAST;
136	}
137
138#ifdef IFF_MULTICAST
139	if ((ifa->ifa_flags & IFF_MULTICAST) != 0) {
140		iter->current.flags |= INTERFACE_F_MULTICAST;
141	}
142#endif
143	iter->current.af = family;
144
145	get_addr(family, &iter->current.address, ifa->ifa_addr, ifa->ifa_name);
146
147	if (ifa->ifa_netmask != NULL)
148		get_addr(family, &iter->current.netmask, ifa->ifa_netmask,
149			 ifa->ifa_name);
150
151	if (ifa->ifa_dstaddr != NULL &&
152	    (iter->current.flags & INTERFACE_F_POINTTOPOINT) != 0)
153		get_addr(family, &iter->current.dstaddress, ifa->ifa_dstaddr,
154			 ifa->ifa_name);
155
156	if (ifa->ifa_broadaddr != NULL &&
157	    (iter->current.flags & INTERFACE_F_BROADCAST) != 0)
158		get_addr(family, &iter->current.broadcast, ifa->ifa_broadaddr,
159			 ifa->ifa_name);
160
161	return (ISC_R_SUCCESS);
162}
163
164/*
165 * Step the iterator to the next interface.  Unlike
166 * isc_interfaceiter_next(), this may leave the iterator
167 * positioned on an interface that will ultimately
168 * be ignored.  Return ISC_R_NOMORE if there are no more
169 * interfaces, otherwise ISC_R_SUCCESS.
170 */
171static isc_result_t
172internal_next(isc_interfaceiter_t *iter) {
173	iter->pos = iter->pos->ifa_next;
174
175	if (iter->pos == NULL)
176		return (ISC_R_NOMORE);
177
178	return (ISC_R_SUCCESS);
179}
180
181static void
182internal_destroy(isc_interfaceiter_t *iter) {
183	if (iter->ifaddrs)
184		freeifaddrs(iter->ifaddrs);
185	iter->ifaddrs = NULL;
186}
187
188static
189void internal_first(isc_interfaceiter_t *iter) {
190	iter->pos = iter->ifaddrs;
191}