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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	lib/libc/asr/getaddrinfo_async.c	Lines:	0	358	0.0 %
Date:	2017-11-13	Branches:	0	295	0.0 %


/*	$OpenBSD: getaddrinfo_async.c,v 1.54 2017/02/27 10:44:46 jca Exp $	*/
/*
 * Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <net/if.h>
#include <netdb.h>

#include <asr.h>
#include <errno.h>
#include <ifaddrs.h>
#include <resolv.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>

#include "asr_private.h"

struct match {
	int family;
	int socktype;
	int protocol;
};

static int getaddrinfo_async_run(struct asr_query *, struct asr_result *);
static int get_port(const char *, const char *, int);
static int iter_family(struct asr_query *, int);
static int addrinfo_add(struct asr_query *, const struct sockaddr *, const char *);
static int addrinfo_from_file(struct asr_query *, int,  FILE *);
static int addrinfo_from_pkt(struct asr_query *, char *, size_t);
static int addrconfig_setup(struct asr_query *);

static const struct match matches[] = {
	{ PF_INET,	SOCK_DGRAM,	IPPROTO_UDP	},
	{ PF_INET,	SOCK_STREAM,	IPPROTO_TCP	},
	{ PF_INET,	SOCK_RAW,	0		},
	{ PF_INET6,	SOCK_DGRAM,	IPPROTO_UDP	},
	{ PF_INET6,	SOCK_STREAM,	IPPROTO_TCP	},
	{ PF_INET6,	SOCK_RAW,	0		},
	{ -1,		0,		0,		},
};

#define MATCH_FAMILY(a, b) ((a) == matches[(b)].family || (a) == PF_UNSPEC)
#define MATCH_PROTO(a, b) ((a) == matches[(b)].protocol || (a) == 0 || matches[(b)].protocol == 0)
/* Do not match SOCK_RAW unless explicitely specified */
#define MATCH_SOCKTYPE(a, b) ((a) == matches[(b)].socktype || ((a) == 0 && \
				matches[(b)].socktype != SOCK_RAW))

enum {
	DOM_INIT,
	DOM_DOMAIN,
	DOM_DONE
};

struct asr_query *
getaddrinfo_async(const char *hostname, const char *servname,
	const struct addrinfo *hints, void *asr)
{
	struct asr_ctx		*ac;
	struct asr_query	*as;

	if (hints == NULL || (hints->ai_flags & AI_NUMERICHOST) == 0)
		ac = _asr_use_resolver(asr);
	else
		ac = _asr_no_resolver();
	if ((as = _asr_async_new(ac, ASR_GETADDRINFO)) == NULL)
		goto abort; /* errno set */
	as->as_run = getaddrinfo_async_run;

	if (hostname) {
		if ((as->as.ai.hostname = strdup(hostname)) == NULL)
			goto abort; /* errno set */
	}
	if (servname && (as->as.ai.servname = strdup(servname)) == NULL)
		goto abort; /* errno set */
	if (hints)
		memmove(&as->as.ai.hints, hints, sizeof *hints);
	else {
		memset(&as->as.ai.hints, 0, sizeof as->as.ai.hints);
		as->as.ai.hints.ai_family = PF_UNSPEC;
		as->as.ai.hints.ai_flags = AI_ADDRCONFIG;
	}

	_asr_ctx_unref(ac);
	return (as);
    abort:
	if (as)
		_asr_async_free(as);
	_asr_ctx_unref(ac);
	return (NULL);
}
DEF_WEAK(getaddrinfo_async);

static int
getaddrinfo_async_run(struct asr_query *as, struct asr_result *ar)
{
	char		 fqdn[MAXDNAME];
	const char	*str;
	struct addrinfo	*ai;
	int		 i, family, r;
	FILE		*f;
	union {
		struct sockaddr		sa;
		struct sockaddr_in	sain;
		struct sockaddr_in6	sain6;
	} sa;

    next:
	switch (as->as_state) {

	case ASR_STATE_INIT:

		/*
		 * First, make sure the parameters are valid.
		 */

		as->as_count = 0;

		if (as->as.ai.hostname == NULL &&
		    as->as.ai.servname == NULL) {
			ar->ar_gai_errno = EAI_NONAME;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (as->as.ai.hostname && as->as.ai.hostname[0] == '\0') {
			ar->ar_gai_errno = EAI_NODATA;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		ai = &as->as.ai.hints;

		if (ai->ai_addrlen ||
		    ai->ai_canonname ||
		    ai->ai_addr ||
		    ai->ai_next) {
			ar->ar_gai_errno = EAI_BADHINTS;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (ai->ai_flags & ~AI_MASK ||
		    (ai->ai_flags & AI_CANONNAME && ai->ai_flags & AI_FQDN)) {
			ar->ar_gai_errno = EAI_BADFLAGS;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (ai->ai_family != PF_UNSPEC &&
		    ai->ai_family != PF_INET &&
		    ai->ai_family != PF_INET6) {
			ar->ar_gai_errno = EAI_FAMILY;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (ai->ai_socktype &&
		    ai->ai_socktype != SOCK_DGRAM  &&
		    ai->ai_socktype != SOCK_STREAM &&
		    ai->ai_socktype != SOCK_RAW) {
			ar->ar_gai_errno = EAI_SOCKTYPE;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (ai->ai_socktype == SOCK_RAW &&
		    get_port(as->as.ai.servname, NULL, 1) != 0) {
			ar->ar_gai_errno = EAI_SERVICE;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		/* Restrict result set to configured address families */
		if (ai->ai_flags & AI_ADDRCONFIG) {
			if (addrconfig_setup(as) == -1) {
				ar->ar_errno = errno;
				ar->ar_gai_errno = EAI_SYSTEM;
				async_set_state(as, ASR_STATE_HALT);
				break;
			}
		}

		/* Make sure there is at least a valid combination */
		for (i = 0; matches[i].family != -1; i++)
			if (MATCH_FAMILY(ai->ai_family, i) &&
			    MATCH_SOCKTYPE(ai->ai_socktype, i) &&
			    MATCH_PROTO(ai->ai_protocol, i))
				break;
		if (matches[i].family == -1) {
			ar->ar_gai_errno = EAI_BADHINTS;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_UDP)
			as->as.ai.port_udp = get_port(as->as.ai.servname, "udp",
			    as->as.ai.hints.ai_flags & AI_NUMERICSERV);
		if (ai->ai_protocol == 0 || ai->ai_protocol == IPPROTO_TCP)
			as->as.ai.port_tcp = get_port(as->as.ai.servname, "tcp",
			    as->as.ai.hints.ai_flags & AI_NUMERICSERV);
		if (as->as.ai.port_tcp == -2 || as->as.ai.port_udp == -2 ||
		    (as->as.ai.port_tcp == -1 && as->as.ai.port_udp == -1) ||
		    (ai->ai_protocol && (as->as.ai.port_udp == -1 ||
					 as->as.ai.port_tcp == -1))) {
			ar->ar_gai_errno = EAI_SERVICE;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		ar->ar_gai_errno = 0;

		/* If hostname is NULL, use local address */
		if (as->as.ai.hostname == NULL) {
			for (family = iter_family(as, 1);
			    family != -1;
			    family = iter_family(as, 0)) {
				/*
				 * We could use statically built sockaddrs for
				 * those, rather than parsing over and over.
				 */
				if (family == PF_INET)
					str = (ai->ai_flags & AI_PASSIVE) ? \
						"0.0.0.0" : "127.0.0.1";
				else /* PF_INET6 */
					str = (ai->ai_flags & AI_PASSIVE) ? \
						"::" : "::1";
				 /* This can't fail */
				_asr_sockaddr_from_str(&sa.sa, family, str);
				if ((r = addrinfo_add(as, &sa.sa, NULL))) {
					ar->ar_gai_errno = r;
					break;
				}
			}
			if (ar->ar_gai_errno == 0 && as->as_count == 0) {
				ar->ar_gai_errno = EAI_NODATA;
			}
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		/* Try numeric addresses first */
		for (family = iter_family(as, 1);
		    family != -1;
		    family = iter_family(as, 0)) {

			if (_asr_sockaddr_from_str(&sa.sa, family,
			    as->as.ai.hostname) == -1)
				continue;

			if ((r = addrinfo_add(as, &sa.sa, NULL)))
				ar->ar_gai_errno = r;
			break;
		}
		if (ar->ar_gai_errno || as->as_count) {
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		if (ai->ai_flags & AI_NUMERICHOST) {
			ar->ar_gai_errno = EAI_NONAME;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		async_set_state(as, ASR_STATE_NEXT_DB);
		break;

	case ASR_STATE_NEXT_DB:
		if (_asr_iter_db(as) == -1) {
			async_set_state(as, ASR_STATE_NOT_FOUND);
			break;
		}
		as->as_family_idx = 0;
		async_set_state(as, ASR_STATE_SAME_DB);
		break;

	case ASR_STATE_NEXT_FAMILY:
		as->as_family_idx += 1;
		if (as->as.ai.hints.ai_family != AF_UNSPEC ||
		    AS_FAMILY(as) == -1) {
			/* The family was specified, or we have tried all
			 * families with this DB.
			 */
			if (as->as_count) {
				ar->ar_gai_errno = 0;
				async_set_state(as, ASR_STATE_HALT);
			} else
				async_set_state(as, ASR_STATE_NEXT_DOMAIN);
			break;
		}
		async_set_state(as, ASR_STATE_SAME_DB);
		break;

	case ASR_STATE_NEXT_DOMAIN:
		/* domain search is only for dns */
		if (AS_DB(as) != ASR_DB_DNS) {
			async_set_state(as, ASR_STATE_NEXT_DB);
			break;
		}
		as->as_family_idx = 0;

		free(as->as.ai.fqdn);
		as->as.ai.fqdn = NULL;
		r = _asr_iter_domain(as, as->as.ai.hostname, fqdn, sizeof(fqdn));
		if (r == -1) {
			async_set_state(as, ASR_STATE_NEXT_DB);
			break;
		}
		if (r == 0) {
			ar->ar_gai_errno = EAI_FAIL;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}
		as->as.ai.fqdn = strdup(fqdn);
		if (as->as.ai.fqdn == NULL) {
			ar->ar_gai_errno = EAI_MEMORY;
			async_set_state(as, ASR_STATE_HALT);
			break;
		}

		async_set_state(as, ASR_STATE_SAME_DB);
		break;

	case ASR_STATE_SAME_DB:
		/* query the current DB again */
		switch (AS_DB(as)) {
		case ASR_DB_DNS:
			if (as->as.ai.fqdn == NULL) {
				/* First try, initialize domain iteration */
				as->as_dom_flags = 0;
				as->as_dom_step = DOM_INIT;
				async_set_state(as, ASR_STATE_NEXT_DOMAIN);
				break;
			}

			family = (as->as.ai.hints.ai_family == AF_UNSPEC) ?
			    AS_FAMILY(as) : as->as.ai.hints.ai_family;

			if (family == AF_INET &&
			    as->as_flags & ASYNC_NO_INET) {
				async_set_state(as, ASR_STATE_NEXT_FAMILY);
				break;
			} else if (family == AF_INET6 &&
			    as->as_flags & ASYNC_NO_INET6) {
				async_set_state(as, ASR_STATE_NEXT_FAMILY);
				break;
			}

			as->as_subq = _res_query_async_ctx(as->as.ai.fqdn,
			    C_IN, (family == AF_INET6) ? T_AAAA : T_A,
			    as->as_ctx);

			if (as->as_subq == NULL) {
				if (errno == ENOMEM)
					ar->ar_gai_errno = EAI_MEMORY;
				else
					ar->ar_gai_errno = EAI_FAIL;
				async_set_state(as, ASR_STATE_HALT);
				break;
			}
			async_set_state(as, ASR_STATE_SUBQUERY);
			break;

		case ASR_DB_FILE:
			f = fopen(_PATH_HOSTS, "re");
			if (f == NULL) {
				async_set_state(as, ASR_STATE_NEXT_DB);
				break;
			}
			family = (as->as.ai.hints.ai_family == AF_UNSPEC) ?
			    AS_FAMILY(as) : as->as.ai.hints.ai_family;

			r = addrinfo_from_file(as, family, f);
			if (r == -1) {
				if (errno == ENOMEM)
					ar->ar_gai_errno = EAI_MEMORY;
				else
					ar->ar_gai_errno = EAI_FAIL;
				async_set_state(as, ASR_STATE_HALT);
			} else
				async_set_state(as, ASR_STATE_NEXT_FAMILY);
			fclose(f);
			break;

		default:
			async_set_state(as, ASR_STATE_NEXT_DB);
		}
		break;

	case ASR_STATE_SUBQUERY:
		if ((r = asr_run(as->as_subq, ar)) == ASYNC_COND)
			return (ASYNC_COND);

		as->as_subq = NULL;

		if (ar->ar_datalen == -1) {
			async_set_state(as, ASR_STATE_NEXT_FAMILY);
			break;
		}

		r = addrinfo_from_pkt(as, ar->ar_data, ar->ar_datalen);
		if (r == -1) {
			if (errno == ENOMEM)
				ar->ar_gai_errno = EAI_MEMORY;
			else
				ar->ar_gai_errno = EAI_FAIL;
			async_set_state(as, ASR_STATE_HALT);
		} else
			async_set_state(as, ASR_STATE_NEXT_FAMILY);
		free(ar->ar_data);
		break;

	case ASR_STATE_NOT_FOUND:
		/* No result found. Maybe we can try again. */
		if (as->as_flags & ASYNC_AGAIN)
			ar->ar_gai_errno = EAI_AGAIN;
		else
			ar->ar_gai_errno = EAI_NODATA;
		async_set_state(as, ASR_STATE_HALT);
		break;

	case ASR_STATE_HALT:
		if (ar->ar_gai_errno == 0) {
			ar->ar_count = as->as_count;
			ar->ar_addrinfo = as->as.ai.aifirst;
			as->as.ai.aifirst = NULL;
		} else {
			ar->ar_count = 0;
			ar->ar_addrinfo = NULL;
		}
		return (ASYNC_DONE);

	default:
		ar->ar_errno = EOPNOTSUPP;
		ar->ar_gai_errno = EAI_SYSTEM;
		async_set_state(as, ASR_STATE_HALT);
		break;
	}
	goto next;
}

/*
 * Retreive the port number for the service name "servname" and
 * the protocol "proto".
 */
static int
get_port(const char *servname, const char *proto, int numonly)
{
	struct servent		se;
	struct servent_data	sed;
	int			port, r;
	const char		*e;

	if (servname == NULL)
		return (0);

	e = NULL;
	port = strtonum(servname, 0, USHRT_MAX, &e);
	if (e == NULL)
		return (port);
	if (errno == ERANGE)
		return (-2); /* invalid */
	if (numonly)
		return (-2);

	memset(&sed, 0, sizeof(sed));
	r = getservbyname_r(servname, proto, &se, &sed);
	port = ntohs(se.s_port);
	endservent_r(&sed);

	if (r == -1)
		return (-1); /* not found */

	return (port);
}

/*
 * Iterate over the address families that are to be queried. Use the
 * list on the async context, unless a specific family was given in hints.
 */
static int
iter_family(struct asr_query *as, int first)
{
	if (first) {
		as->as_family_idx = 0;
		if (as->as.ai.hints.ai_family != PF_UNSPEC)
			return as->as.ai.hints.ai_family;
		return AS_FAMILY(as);
	}

	if (as->as.ai.hints.ai_family != PF_UNSPEC)
		return (-1);

	as->as_family_idx++;

	return AS_FAMILY(as);
}

/*
 * Use the sockaddr at "sa" to extend the result list on the "as" context,
 * with the specified canonical name "cname". This function adds one
 * entry per protocol/socktype match.
 */
static int
addrinfo_add(struct asr_query *as, const struct sockaddr *sa, const char *cname)
{
	struct addrinfo		*ai;
	int			 i, port, proto;

	for (i = 0; matches[i].family != -1; i++) {
		if (matches[i].family != sa->sa_family ||
		    !MATCH_SOCKTYPE(as->as.ai.hints.ai_socktype, i) ||
		    !MATCH_PROTO(as->as.ai.hints.ai_protocol, i))
			continue;

		proto = as->as.ai.hints.ai_protocol;
		if (!proto)
			proto = matches[i].protocol;

		if (proto == IPPROTO_TCP)
			port = as->as.ai.port_tcp;
		else if (proto == IPPROTO_UDP)
			port = as->as.ai.port_udp;
		else
			port = 0;

		/* servname specified, but not defined for this protocol */
		if (port == -1)
			continue;

		ai = calloc(1, sizeof(*ai) + sa->sa_len);
		if (ai == NULL)
			return (EAI_MEMORY);
		ai->ai_family = sa->sa_family;
		ai->ai_socktype = matches[i].socktype;
		ai->ai_protocol = proto;
		ai->ai_flags = as->as.ai.hints.ai_flags;
		ai->ai_addrlen = sa->sa_len;
		ai->ai_addr = (void *)(ai + 1);
		if (cname &&
		    as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN)) {
			if ((ai->ai_canonname = strdup(cname)) == NULL) {
				free(ai);
				return (EAI_MEMORY);
			}
		}
		memmove(ai->ai_addr, sa, sa->sa_len);
		if (sa->sa_family == PF_INET)
			((struct sockaddr_in *)ai->ai_addr)->sin_port =
			    htons(port);
		else if (sa->sa_family == PF_INET6)
			((struct sockaddr_in6 *)ai->ai_addr)->sin6_port =
			    htons(port);

		if (as->as.ai.aifirst == NULL)
			as->as.ai.aifirst = ai;
		if (as->as.ai.ailast)
			as->as.ai.ailast->ai_next = ai;
		as->as.ai.ailast = ai;
		as->as_count += 1;
	}

	return (0);
}

static int
addrinfo_from_file(struct asr_query *as, int family, FILE *f)
{
	char		*tokens[MAXTOKEN], *c, buf[BUFSIZ + 1];
	int		 n, i;
	union {
		struct sockaddr		sa;
		struct sockaddr_in	sain;
		struct sockaddr_in6	sain6;
	} u;

	for (;;) {
		n = _asr_parse_namedb_line(f, tokens, MAXTOKEN, buf, sizeof(buf));
		if (n == -1)
			break; /* ignore errors reading the file */

		for (i = 1; i < n; i++) {
			if (strcasecmp(as->as.ai.hostname, tokens[i]))
				continue;
			if (_asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1)
				continue;
			break;
		}
		if (i == n)
			continue;

		if (as->as.ai.hints.ai_flags & (AI_CANONNAME | AI_FQDN))
			c = tokens[1];
		else
			c = NULL;

		if (addrinfo_add(as, &u.sa, c))
			return (-1); /* errno set */
	}
	return (0);
}

static int
addrinfo_from_pkt(struct asr_query *as, char *pkt, size_t pktlen)
{
	struct asr_unpack	 p;
	struct asr_dns_header	 h;
	struct asr_dns_query	 q;
	struct asr_dns_rr	 rr;
	int			 i;
	union {
		struct sockaddr		sa;
		struct sockaddr_in	sain;
		struct sockaddr_in6	sain6;
	} u;
	char		 buf[MAXDNAME], *c;

	_asr_unpack_init(&p, pkt, pktlen);
	_asr_unpack_header(&p, &h);
	for (; h.qdcount; h.qdcount--)
		_asr_unpack_query(&p, &q);

	for (i = 0; i < h.ancount; i++) {
		_asr_unpack_rr(&p, &rr);
		if (rr.rr_type != q.q_type ||
		    rr.rr_class != q.q_class)
			continue;

		memset(&u, 0, sizeof u);
		if (rr.rr_type == T_A) {
			u.sain.sin_len = sizeof u.sain;
			u.sain.sin_family = AF_INET;
			u.sain.sin_addr = rr.rr.in_a.addr;
			u.sain.sin_port = 0;
		} else if (rr.rr_type == T_AAAA) {
			u.sain6.sin6_len = sizeof u.sain6;
			u.sain6.sin6_family = AF_INET6;
			u.sain6.sin6_addr = rr.rr.in_aaaa.addr6;
			u.sain6.sin6_port = 0;
		} else
			continue;

		if (as->as.ai.hints.ai_flags & AI_CANONNAME) {
			_asr_strdname(rr.rr_dname, buf, sizeof buf);
			buf[strlen(buf) - 1] = '\0';
			c = res_hnok(buf) ? buf : NULL;
		} else if (as->as.ai.hints.ai_flags & AI_FQDN)
			c = as->as.ai.fqdn;
		else
			c = NULL;

		if (addrinfo_add(as, &u.sa, c))
			return (-1); /* errno set */
	}
	return (0);
}

static int
addrconfig_setup(struct asr_query *as)
{
	struct ifaddrs		*ifa, *ifa0;
	struct sockaddr_in	*sinp;
	struct sockaddr_in6	*sin6p;

	if (getifaddrs(&ifa0) == -1)
		return (-1);

	as->as_flags |= ASYNC_NO_INET | ASYNC_NO_INET6;

	for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) {
		if (ifa->ifa_addr == NULL)
			continue;

		switch (ifa->ifa_addr->sa_family) {
		case PF_INET:
			sinp = (struct sockaddr_in *)ifa->ifa_addr;

			if (sinp->sin_addr.s_addr == htonl(INADDR_LOOPBACK))
				continue;

			as->as_flags &= ~ASYNC_NO_INET;
			break;
		case PF_INET6:
			sin6p = (struct sockaddr_in6 *)ifa->ifa_addr;

			if (IN6_IS_ADDR_LOOPBACK(&sin6p->sin6_addr))
				continue;

			if (IN6_IS_ADDR_LINKLOCAL(&sin6p->sin6_addr))
				continue;

			as->as_flags &= ~ASYNC_NO_INET6;
			break;
		}
	}

	freeifaddrs(ifa0);

	return (0);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: getaddrinfo_async.c,v 1.54 2017/02/27 10:44:46 jca Exp $ */
2			/*
3			* Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
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 THE AUTHOR DISCLAIMS ALL WARRANTIES
10			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16			*/
17
18			#include <sys/types.h>
19			#include <sys/socket.h>
20			#include <sys/uio.h>
21			#include <netinet/in.h>
22			#include <arpa/nameser.h>
23			#include <net/if.h>
24			#include <netdb.h>
25
26			#include <asr.h>
27			#include <errno.h>
28			#include <ifaddrs.h>
29			#include <resolv.h>
30			#include <stdlib.h>
31			#include <string.h>
32			#include <unistd.h>
33			#include <limits.h>
34
35			#include "asr_private.h"
36
37			struct match {
38			int family;
39			int socktype;
40			int protocol;
41			};
42
43			static int getaddrinfo_async_run(struct asr_query , struct asr_result );
44			static int get_port(const char , const char , int);
45			static int iter_family(struct asr_query *, int);
46			static int addrinfo_add(struct asr_query , const struct sockaddr , const char *);
47			static int addrinfo_from_file(struct asr_query , int, FILE );
48			static int addrinfo_from_pkt(struct asr_query , char , size_t);
49			static int addrconfig_setup(struct asr_query *);
50
51			static const struct match matches[] = {
52			{ PF_INET, SOCK_DGRAM, IPPROTO_UDP },
53			{ PF_INET, SOCK_STREAM, IPPROTO_TCP },
54			{ PF_INET, SOCK_RAW, 0 },
55			{ PF_INET6, SOCK_DGRAM, IPPROTO_UDP },
56			{ PF_INET6, SOCK_STREAM, IPPROTO_TCP },
57			{ PF_INET6, SOCK_RAW, 0 },
58			{ -1, 0, 0, },
59			};
60
61			#define MATCH_FAMILY(a, b) ((a) == matches[(b)].family \|\| (a) == PF_UNSPEC)
62			#define MATCH_PROTO(a, b) ((a) == matches[(b)].protocol \|\| (a) == 0 \|\| matches[(b)].protocol == 0)
63			/* Do not match SOCK_RAW unless explicitely specified */
64			#define MATCH_SOCKTYPE(a, b) ((a) == matches[(b)].socktype \|\| ((a) == 0 && \
65			matches[(b)].socktype != SOCK_RAW))
66
67			enum {
68			DOM_INIT,
69			DOM_DOMAIN,
70			DOM_DONE
71			};
72
73			struct asr_query *
74			getaddrinfo_async(const char hostname, const char servname,
75			const struct addrinfo hints, void asr)
76			{
77			struct asr_ctx *ac;
78			struct asr_query *as;
79
80			if (hints == NULL \|\| (hints->ai_flags & AI_NUMERICHOST) == 0)
81			ac = _asr_use_resolver(asr);
82			else
83			ac = _asr_no_resolver();
84			if ((as = _asr_async_new(ac, ASR_GETADDRINFO)) == NULL)
85			goto abort; /* errno set */
86			as->as_run = getaddrinfo_async_run;
87
88			if (hostname) {
89			if ((as->as.ai.hostname = strdup(hostname)) == NULL)
90			goto abort; /* errno set */
91			}
92			if (servname && (as->as.ai.servname = strdup(servname)) == NULL)
93			goto abort; /* errno set */
94			if (hints)
95			memmove(&as->as.ai.hints, hints, sizeof *hints);
96			else {
97			memset(&as->as.ai.hints, 0, sizeof as->as.ai.hints);
98			as->as.ai.hints.ai_family = PF_UNSPEC;
99			as->as.ai.hints.ai_flags = AI_ADDRCONFIG;
100			}
101
102			_asr_ctx_unref(ac);
103			return (as);
104			abort:
105			if (as)
106			_asr_async_free(as);
107			_asr_ctx_unref(ac);
108			return (NULL);
109			}
110			DEF_WEAK(getaddrinfo_async);
111
112			static int
113			getaddrinfo_async_run(struct asr_query as, struct asr_result ar)
114			{
115			char fqdn[MAXDNAME];
116			const char *str;
117			struct addrinfo *ai;
118			int i, family, r;
119			FILE *f;
120			union {
121			struct sockaddr sa;
122			struct sockaddr_in sain;
123			struct sockaddr_in6 sain6;
124			} sa;
125
126			next:
127			switch (as->as_state) {
128
129			case ASR_STATE_INIT:
130
131			/*
132			* First, make sure the parameters are valid.
133			*/
134
135			as->as_count = 0;
136
137			if (as->as.ai.hostname == NULL &&
138			as->as.ai.servname == NULL) {
139			ar->ar_gai_errno = EAI_NONAME;
140			async_set_state(as, ASR_STATE_HALT);
141			break;
142			}
143
144			if (as->as.ai.hostname && as->as.ai.hostname[0] == '\0') {
145			ar->ar_gai_errno = EAI_NODATA;
146			async_set_state(as, ASR_STATE_HALT);
147			break;
148			}
149
150			ai = &as->as.ai.hints;
151
152			if (ai->ai_addrlen \|\|
153			ai->ai_canonname \|\|
154			ai->ai_addr \|\|
155			ai->ai_next) {
156			ar->ar_gai_errno = EAI_BADHINTS;
157			async_set_state(as, ASR_STATE_HALT);
158			break;
159			}
160
161			if (ai->ai_flags & ~AI_MASK \|\|
162			(ai->ai_flags & AI_CANONNAME && ai->ai_flags & AI_FQDN)) {
163			ar->ar_gai_errno = EAI_BADFLAGS;
164			async_set_state(as, ASR_STATE_HALT);
165			break;
166			}
167
168			if (ai->ai_family != PF_UNSPEC &&
169			ai->ai_family != PF_INET &&
170			ai->ai_family != PF_INET6) {
171			ar->ar_gai_errno = EAI_FAMILY;
172			async_set_state(as, ASR_STATE_HALT);
173			break;
174			}
175
176			if (ai->ai_socktype &&
177			ai->ai_socktype != SOCK_DGRAM &&
178			ai->ai_socktype != SOCK_STREAM &&
179			ai->ai_socktype != SOCK_RAW) {
180			ar->ar_gai_errno = EAI_SOCKTYPE;
181			async_set_state(as, ASR_STATE_HALT);
182			break;
183			}
184
185			if (ai->ai_socktype == SOCK_RAW &&
186			get_port(as->as.ai.servname, NULL, 1) != 0) {
187			ar->ar_gai_errno = EAI_SERVICE;
188			async_set_state(as, ASR_STATE_HALT);
189			break;
190			}
191
192			/* Restrict result set to configured address families */
193			if (ai->ai_flags & AI_ADDRCONFIG) {
194			if (addrconfig_setup(as) == -1) {
195			ar->ar_errno = errno;
196			ar->ar_gai_errno = EAI_SYSTEM;
197			async_set_state(as, ASR_STATE_HALT);
198			break;
199			}
200			}
201
202			/* Make sure there is at least a valid combination */
203			for (i = 0; matches[i].family != -1; i++)
204			if (MATCH_FAMILY(ai->ai_family, i) &&
205			MATCH_SOCKTYPE(ai->ai_socktype, i) &&
206			MATCH_PROTO(ai->ai_protocol, i))
207			break;
208			if (matches[i].family == -1) {
209			ar->ar_gai_errno = EAI_BADHINTS;
210			async_set_state(as, ASR_STATE_HALT);
211			break;
212			}
213
214			if (ai->ai_protocol == 0 \|\| ai->ai_protocol == IPPROTO_UDP)
215			as->as.ai.port_udp = get_port(as->as.ai.servname, "udp",
216			as->as.ai.hints.ai_flags & AI_NUMERICSERV);
217			if (ai->ai_protocol == 0 \|\| ai->ai_protocol == IPPROTO_TCP)
218			as->as.ai.port_tcp = get_port(as->as.ai.servname, "tcp",
219			as->as.ai.hints.ai_flags & AI_NUMERICSERV);
220			if (as->as.ai.port_tcp == -2 \|\| as->as.ai.port_udp == -2 \|\|
221			(as->as.ai.port_tcp == -1 && as->as.ai.port_udp == -1) \|\|
222			(ai->ai_protocol && (as->as.ai.port_udp == -1 \|\|
223			as->as.ai.port_tcp == -1))) {
224			ar->ar_gai_errno = EAI_SERVICE;
225			async_set_state(as, ASR_STATE_HALT);
226			break;
227			}
228
229			ar->ar_gai_errno = 0;
230
231			/* If hostname is NULL, use local address */
232			if (as->as.ai.hostname == NULL) {
233			for (family = iter_family(as, 1);
234			family != -1;
235			family = iter_family(as, 0)) {
236			/*
237			* We could use statically built sockaddrs for
238			* those, rather than parsing over and over.
239			*/
240			if (family == PF_INET)
241			str = (ai->ai_flags & AI_PASSIVE) ? \
242			"0.0.0.0" : "127.0.0.1";
243			else /* PF_INET6 */
244			str = (ai->ai_flags & AI_PASSIVE) ? \
245			"::" : "::1";
246			/* This can't fail */
247			_asr_sockaddr_from_str(&sa.sa, family, str);
248			if ((r = addrinfo_add(as, &sa.sa, NULL))) {
249			ar->ar_gai_errno = r;
250			break;
251			}
252			}
253			if (ar->ar_gai_errno == 0 && as->as_count == 0) {
254			ar->ar_gai_errno = EAI_NODATA;
255			}
256			async_set_state(as, ASR_STATE_HALT);
257			break;
258			}
259
260			/* Try numeric addresses first */
261			for (family = iter_family(as, 1);
262			family != -1;
263			family = iter_family(as, 0)) {
264
265			if (_asr_sockaddr_from_str(&sa.sa, family,
266			as->as.ai.hostname) == -1)
267			continue;
268
269			if ((r = addrinfo_add(as, &sa.sa, NULL)))
270			ar->ar_gai_errno = r;
271			break;
272			}
273			if (ar->ar_gai_errno \|\| as->as_count) {
274			async_set_state(as, ASR_STATE_HALT);
275			break;
276			}
277
278			if (ai->ai_flags & AI_NUMERICHOST) {
279			ar->ar_gai_errno = EAI_NONAME;
280			async_set_state(as, ASR_STATE_HALT);
281			break;
282			}
283
284			async_set_state(as, ASR_STATE_NEXT_DB);
285			break;
286
287			case ASR_STATE_NEXT_DB:
288			if (_asr_iter_db(as) == -1) {
289			async_set_state(as, ASR_STATE_NOT_FOUND);
290			break;
291			}
292			as->as_family_idx = 0;
293			async_set_state(as, ASR_STATE_SAME_DB);
294			break;
295
296			case ASR_STATE_NEXT_FAMILY:
297			as->as_family_idx += 1;
298			if (as->as.ai.hints.ai_family != AF_UNSPEC \|\|
299			AS_FAMILY(as) == -1) {
300			/* The family was specified, or we have tried all
301			* families with this DB.
302			*/
303			if (as->as_count) {
304			ar->ar_gai_errno = 0;
305			async_set_state(as, ASR_STATE_HALT);
306			} else
307			async_set_state(as, ASR_STATE_NEXT_DOMAIN);
308			break;
309			}
310			async_set_state(as, ASR_STATE_SAME_DB);
311			break;
312
313			case ASR_STATE_NEXT_DOMAIN:
314			/* domain search is only for dns */
315			if (AS_DB(as) != ASR_DB_DNS) {
316			async_set_state(as, ASR_STATE_NEXT_DB);
317			break;
318			}
319			as->as_family_idx = 0;
320
321			free(as->as.ai.fqdn);
322			as->as.ai.fqdn = NULL;
323			r = _asr_iter_domain(as, as->as.ai.hostname, fqdn, sizeof(fqdn));
324			if (r == -1) {
325			async_set_state(as, ASR_STATE_NEXT_DB);
326			break;
327			}
328			if (r == 0) {
329			ar->ar_gai_errno = EAI_FAIL;
330			async_set_state(as, ASR_STATE_HALT);
331			break;
332			}
333			as->as.ai.fqdn = strdup(fqdn);
334			if (as->as.ai.fqdn == NULL) {
335			ar->ar_gai_errno = EAI_MEMORY;
336			async_set_state(as, ASR_STATE_HALT);
337			break;
338			}
339
340			async_set_state(as, ASR_STATE_SAME_DB);
341			break;
342
343			case ASR_STATE_SAME_DB:
344			/* query the current DB again */
345			switch (AS_DB(as)) {
346			case ASR_DB_DNS:
347			if (as->as.ai.fqdn == NULL) {
348			/* First try, initialize domain iteration */
349			as->as_dom_flags = 0;
350			as->as_dom_step = DOM_INIT;
351			async_set_state(as, ASR_STATE_NEXT_DOMAIN);
352			break;
353			}
354
355			family = (as->as.ai.hints.ai_family == AF_UNSPEC) ?
356			AS_FAMILY(as) : as->as.ai.hints.ai_family;
357
358			if (family == AF_INET &&
359			as->as_flags & ASYNC_NO_INET) {
360			async_set_state(as, ASR_STATE_NEXT_FAMILY);
361			break;
362			} else if (family == AF_INET6 &&
363			as->as_flags & ASYNC_NO_INET6) {
364			async_set_state(as, ASR_STATE_NEXT_FAMILY);
365			break;
366			}
367
368			as->as_subq = _res_query_async_ctx(as->as.ai.fqdn,
369			C_IN, (family == AF_INET6) ? T_AAAA : T_A,
370			as->as_ctx);
371
372			if (as->as_subq == NULL) {
373			if (errno == ENOMEM)
374			ar->ar_gai_errno = EAI_MEMORY;
375			else
376			ar->ar_gai_errno = EAI_FAIL;
377			async_set_state(as, ASR_STATE_HALT);
378			break;
379			}
380			async_set_state(as, ASR_STATE_SUBQUERY);
381			break;
382
383			case ASR_DB_FILE:
384			f = fopen(_PATH_HOSTS, "re");
385			if (f == NULL) {
386			async_set_state(as, ASR_STATE_NEXT_DB);
387			break;
388			}
389			family = (as->as.ai.hints.ai_family == AF_UNSPEC) ?
390			AS_FAMILY(as) : as->as.ai.hints.ai_family;
391
392			r = addrinfo_from_file(as, family, f);
393			if (r == -1) {
394			if (errno == ENOMEM)
395			ar->ar_gai_errno = EAI_MEMORY;
396			else
397			ar->ar_gai_errno = EAI_FAIL;
398			async_set_state(as, ASR_STATE_HALT);
399			} else
400			async_set_state(as, ASR_STATE_NEXT_FAMILY);
401			fclose(f);
402			break;
403
404			default:
405			async_set_state(as, ASR_STATE_NEXT_DB);
406			}
407			break;
408
409			case ASR_STATE_SUBQUERY:
410			if ((r = asr_run(as->as_subq, ar)) == ASYNC_COND)
411			return (ASYNC_COND);
412
413			as->as_subq = NULL;
414
415			if (ar->ar_datalen == -1) {
416			async_set_state(as, ASR_STATE_NEXT_FAMILY);
417			break;
418			}
419
420			r = addrinfo_from_pkt(as, ar->ar_data, ar->ar_datalen);
421			if (r == -1) {
422			if (errno == ENOMEM)
423			ar->ar_gai_errno = EAI_MEMORY;
424			else
425			ar->ar_gai_errno = EAI_FAIL;
426			async_set_state(as, ASR_STATE_HALT);
427			} else
428			async_set_state(as, ASR_STATE_NEXT_FAMILY);
429			free(ar->ar_data);
430			break;
431
432			case ASR_STATE_NOT_FOUND:
433			/* No result found. Maybe we can try again. */
434			if (as->as_flags & ASYNC_AGAIN)
435			ar->ar_gai_errno = EAI_AGAIN;
436			else
437			ar->ar_gai_errno = EAI_NODATA;
438			async_set_state(as, ASR_STATE_HALT);
439			break;
440
441			case ASR_STATE_HALT:
442			if (ar->ar_gai_errno == 0) {
443			ar->ar_count = as->as_count;
444			ar->ar_addrinfo = as->as.ai.aifirst;
445			as->as.ai.aifirst = NULL;
446			} else {
447			ar->ar_count = 0;
448			ar->ar_addrinfo = NULL;
449			}
450			return (ASYNC_DONE);
451
452			default:
453			ar->ar_errno = EOPNOTSUPP;
454			ar->ar_gai_errno = EAI_SYSTEM;
455			async_set_state(as, ASR_STATE_HALT);
456			break;
457			}
458			goto next;
459			}
460
461			/*
462			* Retreive the port number for the service name "servname" and
463			* the protocol "proto".
464			*/
465			static int
466			get_port(const char servname, const char proto, int numonly)
467			{
468			struct servent se;
469			struct servent_data sed;
470			int port, r;
471			const char *e;
472
473			if (servname == NULL)
474			return (0);
475
476			e = NULL;
477			port = strtonum(servname, 0, USHRT_MAX, &e);
478			if (e == NULL)
479			return (port);
480			if (errno == ERANGE)
481			return (-2); /* invalid */
482			if (numonly)
483			return (-2);
484
485			memset(&sed, 0, sizeof(sed));
486			r = getservbyname_r(servname, proto, &se, &sed);
487			port = ntohs(se.s_port);
488			endservent_r(&sed);
489
490			if (r == -1)
491			return (-1); /* not found */
492
493			return (port);
494			}
495
496			/*
497			* Iterate over the address families that are to be queried. Use the
498			* list on the async context, unless a specific family was given in hints.
499			*/
500			static int
501			iter_family(struct asr_query *as, int first)
502			{
503			if (first) {
504			as->as_family_idx = 0;
505			if (as->as.ai.hints.ai_family != PF_UNSPEC)
506			return as->as.ai.hints.ai_family;
507			return AS_FAMILY(as);
508			}
509
510			if (as->as.ai.hints.ai_family != PF_UNSPEC)
511			return (-1);
512
513			as->as_family_idx++;
514
515			return AS_FAMILY(as);
516			}
517
518			/*
519			* Use the sockaddr at "sa" to extend the result list on the "as" context,
520			* with the specified canonical name "cname". This function adds one
521			* entry per protocol/socktype match.
522			*/
523			static int
524			addrinfo_add(struct asr_query as, const struct sockaddr sa, const char *cname)
525			{
526			struct addrinfo *ai;
527			int i, port, proto;
528
529			for (i = 0; matches[i].family != -1; i++) {
530			if (matches[i].family != sa->sa_family \|\|
531			!MATCH_SOCKTYPE(as->as.ai.hints.ai_socktype, i) \|\|
532			!MATCH_PROTO(as->as.ai.hints.ai_protocol, i))
533			continue;
534
535			proto = as->as.ai.hints.ai_protocol;
536			if (!proto)
537			proto = matches[i].protocol;
538
539			if (proto == IPPROTO_TCP)
540			port = as->as.ai.port_tcp;
541			else if (proto == IPPROTO_UDP)
542			port = as->as.ai.port_udp;
543			else
544			port = 0;
545
546			/* servname specified, but not defined for this protocol */
547			if (port == -1)
548			continue;
549
550			ai = calloc(1, sizeof(*ai) + sa->sa_len);
551			if (ai == NULL)
552			return (EAI_MEMORY);
553			ai->ai_family = sa->sa_family;
554			ai->ai_socktype = matches[i].socktype;
555			ai->ai_protocol = proto;
556			ai->ai_flags = as->as.ai.hints.ai_flags;
557			ai->ai_addrlen = sa->sa_len;
558			ai->ai_addr = (void *)(ai + 1);
559			if (cname &&
560			as->as.ai.hints.ai_flags & (AI_CANONNAME \| AI_FQDN)) {
561			if ((ai->ai_canonname = strdup(cname)) == NULL) {
562			free(ai);
563			return (EAI_MEMORY);
564			}
565			}
566			memmove(ai->ai_addr, sa, sa->sa_len);
567			if (sa->sa_family == PF_INET)
568			((struct sockaddr_in *)ai->ai_addr)->sin_port =
569			htons(port);
570			else if (sa->sa_family == PF_INET6)
571			((struct sockaddr_in6 *)ai->ai_addr)->sin6_port =
572			htons(port);
573
574			if (as->as.ai.aifirst == NULL)
575			as->as.ai.aifirst = ai;
576			if (as->as.ai.ailast)
577			as->as.ai.ailast->ai_next = ai;
578			as->as.ai.ailast = ai;
579			as->as_count += 1;
580			}
581
582			return (0);
583			}
584
585			static int
586			addrinfo_from_file(struct asr_query as, int family, FILE f)
587			{
588			char tokens[MAXTOKEN], c, buf[BUFSIZ + 1];
589			int n, i;
590			union {
591			struct sockaddr sa;
592			struct sockaddr_in sain;
593			struct sockaddr_in6 sain6;
594			} u;
595
596			for (;;) {
597			n = _asr_parse_namedb_line(f, tokens, MAXTOKEN, buf, sizeof(buf));
598			if (n == -1)
599			break; /* ignore errors reading the file */
600
601			for (i = 1; i < n; i++) {
602			if (strcasecmp(as->as.ai.hostname, tokens[i]))
603			continue;
604			if (_asr_sockaddr_from_str(&u.sa, family, tokens[0]) == -1)
605			continue;
606			break;
607			}
608			if (i == n)
609			continue;
610
611			if (as->as.ai.hints.ai_flags & (AI_CANONNAME \| AI_FQDN))
612			c = tokens[1];
613			else
614			c = NULL;
615
616			if (addrinfo_add(as, &u.sa, c))
617			return (-1); /* errno set */
618			}
619			return (0);
620			}
621
622			static int
623			addrinfo_from_pkt(struct asr_query as, char pkt, size_t pktlen)
624			{
625			struct asr_unpack p;
626			struct asr_dns_header h;
627			struct asr_dns_query q;
628			struct asr_dns_rr rr;
629			int i;
630			union {
631			struct sockaddr sa;
632			struct sockaddr_in sain;
633			struct sockaddr_in6 sain6;
634			} u;
635			char buf[MAXDNAME], *c;
636
637			_asr_unpack_init(&p, pkt, pktlen);
638			_asr_unpack_header(&p, &h);
639			for (; h.qdcount; h.qdcount--)
640			_asr_unpack_query(&p, &q);
641
642			for (i = 0; i < h.ancount; i++) {
643			_asr_unpack_rr(&p, &rr);
644			if (rr.rr_type != q.q_type \|\|
645			rr.rr_class != q.q_class)
646			continue;
647
648			memset(&u, 0, sizeof u);
649			if (rr.rr_type == T_A) {
650			u.sain.sin_len = sizeof u.sain;
651			u.sain.sin_family = AF_INET;
652			u.sain.sin_addr = rr.rr.in_a.addr;
653			u.sain.sin_port = 0;
654			} else if (rr.rr_type == T_AAAA) {
655			u.sain6.sin6_len = sizeof u.sain6;
656			u.sain6.sin6_family = AF_INET6;
657			u.sain6.sin6_addr = rr.rr.in_aaaa.addr6;
658			u.sain6.sin6_port = 0;
659			} else
660			continue;
661
662			if (as->as.ai.hints.ai_flags & AI_CANONNAME) {
663			_asr_strdname(rr.rr_dname, buf, sizeof buf);
664			buf[strlen(buf) - 1] = '\0';
665			c = res_hnok(buf) ? buf : NULL;
666			} else if (as->as.ai.hints.ai_flags & AI_FQDN)
667			c = as->as.ai.fqdn;
668			else
669			c = NULL;
670
671			if (addrinfo_add(as, &u.sa, c))
672			return (-1); /* errno set */
673			}
674			return (0);
675			}
676
677			static int
678			addrconfig_setup(struct asr_query *as)
679			{
680			struct ifaddrs ifa, ifa0;
681			struct sockaddr_in *sinp;
682			struct sockaddr_in6 *sin6p;
683
684			if (getifaddrs(&ifa0) == -1)
685			return (-1);
686
687			as->as_flags \|= ASYNC_NO_INET \| ASYNC_NO_INET6;
688
689			for (ifa = ifa0; ifa != NULL; ifa = ifa->ifa_next) {
690			if (ifa->ifa_addr == NULL)
691			continue;
692
693			switch (ifa->ifa_addr->sa_family) {
694			case PF_INET:
695			sinp = (struct sockaddr_in *)ifa->ifa_addr;
696
697			if (sinp->sin_addr.s_addr == htonl(INADDR_LOOPBACK))
698			continue;
699
700			as->as_flags &= ~ASYNC_NO_INET;
701			break;
702			case PF_INET6:
703			sin6p = (struct sockaddr_in6 *)ifa->ifa_addr;
704
705			if (IN6_IS_ADDR_LOOPBACK(&sin6p->sin6_addr))
706			continue;
707
708			if (IN6_IS_ADDR_LINKLOCAL(&sin6p->sin6_addr))
709			continue;
710
711			as->as_flags &= ~ASYNC_NO_INET6;
712			break;
713			}
714			}
715
716			freeifaddrs(ifa0);
717
718			return (0);
719			}