1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
3*0Sstevel@tonic-gate  * Use is subject to license terms.
4*0Sstevel@tonic-gate  */
5*0Sstevel@tonic-gate 
6*0Sstevel@tonic-gate /*
7*0Sstevel@tonic-gate  * Copyright (c) 1985, 1988, 1993
8*0Sstevel@tonic-gate  *    The Regents of the University of California.  All rights reserved.
9*0Sstevel@tonic-gate  *
10*0Sstevel@tonic-gate  * Redistribution and use in source and binary forms, with or without
11*0Sstevel@tonic-gate  * modification, are permitted provided that the following conditions
12*0Sstevel@tonic-gate  * are met:
13*0Sstevel@tonic-gate  * 1. Redistributions of source code must retain the above copyright
14*0Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer.
15*0Sstevel@tonic-gate  * 2. Redistributions in binary form must reproduce the above copyright
16*0Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer in the
17*0Sstevel@tonic-gate  *    documentation and/or other materials provided with the distribution.
18*0Sstevel@tonic-gate  * 3. All advertising materials mentioning features or use of this software
19*0Sstevel@tonic-gate  *    must display the following acknowledgement:
20*0Sstevel@tonic-gate  * 	This product includes software developed by the University of
21*0Sstevel@tonic-gate  * 	California, Berkeley and its contributors.
22*0Sstevel@tonic-gate  * 4. Neither the name of the University nor the names of its contributors
23*0Sstevel@tonic-gate  *    may be used to endorse or promote products derived from this software
24*0Sstevel@tonic-gate  *    without specific prior written permission.
25*0Sstevel@tonic-gate  *
26*0Sstevel@tonic-gate  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27*0Sstevel@tonic-gate  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28*0Sstevel@tonic-gate  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29*0Sstevel@tonic-gate  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30*0Sstevel@tonic-gate  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31*0Sstevel@tonic-gate  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32*0Sstevel@tonic-gate  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33*0Sstevel@tonic-gate  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34*0Sstevel@tonic-gate  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35*0Sstevel@tonic-gate  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36*0Sstevel@tonic-gate  * SUCH DAMAGE.
37*0Sstevel@tonic-gate  */
38*0Sstevel@tonic-gate 
39*0Sstevel@tonic-gate /*
40*0Sstevel@tonic-gate  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
41*0Sstevel@tonic-gate  *
42*0Sstevel@tonic-gate  * Permission to use, copy, modify, and distribute this software for any
43*0Sstevel@tonic-gate  * purpose with or without fee is hereby granted, provided that the above
44*0Sstevel@tonic-gate  * copyright notice and this permission notice appear in all copies.
45*0Sstevel@tonic-gate  *
46*0Sstevel@tonic-gate  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
47*0Sstevel@tonic-gate  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
48*0Sstevel@tonic-gate  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
49*0Sstevel@tonic-gate  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
50*0Sstevel@tonic-gate  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
51*0Sstevel@tonic-gate  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
52*0Sstevel@tonic-gate  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
53*0Sstevel@tonic-gate  * SOFTWARE.
54*0Sstevel@tonic-gate  */
55*0Sstevel@tonic-gate 
56*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
57*0Sstevel@tonic-gate 
58*0Sstevel@tonic-gate /* from gethostnamadr.c	8.1 (Berkeley) 6/4/93 */
59*0Sstevel@tonic-gate /* BIND Id: gethnamaddr.c,v 8.15 1996/05/22 04:56:30 vixie Exp $ */
60*0Sstevel@tonic-gate 
61*0Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint)
62*0Sstevel@tonic-gate static const char rcsid[] = "$Id: dns_ho.c,v 1.43 2003/05/27 23:36:52 marka Exp $";
63*0Sstevel@tonic-gate #endif /* LIBC_SCCS and not lint */
64*0Sstevel@tonic-gate 
65*0Sstevel@tonic-gate /* Imports. */
66*0Sstevel@tonic-gate 
67*0Sstevel@tonic-gate #include "port_before.h"
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate #include <sys/types.h>
70*0Sstevel@tonic-gate #include <sys/param.h>
71*0Sstevel@tonic-gate #include <sys/socket.h>
72*0Sstevel@tonic-gate 
73*0Sstevel@tonic-gate #include <netinet/in.h>
74*0Sstevel@tonic-gate #include <arpa/inet.h>
75*0Sstevel@tonic-gate #include <arpa/nameser.h>
76*0Sstevel@tonic-gate 
77*0Sstevel@tonic-gate #include <ctype.h>
78*0Sstevel@tonic-gate #include <errno.h>
79*0Sstevel@tonic-gate #include <stdlib.h>
80*0Sstevel@tonic-gate #include <netdb.h>
81*0Sstevel@tonic-gate #include <resolv.h>
82*0Sstevel@tonic-gate #include <stdio.h>
83*0Sstevel@tonic-gate #include <string.h>
84*0Sstevel@tonic-gate #include <syslog.h>
85*0Sstevel@tonic-gate 
86*0Sstevel@tonic-gate #include <isc/memcluster.h>
87*0Sstevel@tonic-gate #include <irs.h>
88*0Sstevel@tonic-gate 
89*0Sstevel@tonic-gate #include "port_after.h"
90*0Sstevel@tonic-gate 
91*0Sstevel@tonic-gate #include "irs_p.h"
92*0Sstevel@tonic-gate #include "dns_p.h"
93*0Sstevel@tonic-gate 
94*0Sstevel@tonic-gate #ifdef SPRINTF_CHAR
95*0Sstevel@tonic-gate # define SPRINTF(x) strlen(sprintf/**/x)
96*0Sstevel@tonic-gate #else
97*0Sstevel@tonic-gate # define SPRINTF(x) sprintf x
98*0Sstevel@tonic-gate #endif
99*0Sstevel@tonic-gate 
100*0Sstevel@tonic-gate /* Definitions. */
101*0Sstevel@tonic-gate 
102*0Sstevel@tonic-gate #define	MAXALIASES	35
103*0Sstevel@tonic-gate #define	MAXADDRS	35
104*0Sstevel@tonic-gate 
105*0Sstevel@tonic-gate #define MAXPACKET (65535)	/* Maximum TCP message size */
106*0Sstevel@tonic-gate 
107*0Sstevel@tonic-gate #define BOUNDS_CHECK(ptr, count) \
108*0Sstevel@tonic-gate 	if ((ptr) + (count) > eom) { \
109*0Sstevel@tonic-gate 		had_error++; \
110*0Sstevel@tonic-gate 		continue; \
111*0Sstevel@tonic-gate 	} else (void)0
112*0Sstevel@tonic-gate 
113*0Sstevel@tonic-gate typedef union {
114*0Sstevel@tonic-gate 	HEADER hdr;
115*0Sstevel@tonic-gate 	u_char buf[MAXPACKET];
116*0Sstevel@tonic-gate } querybuf;
117*0Sstevel@tonic-gate 
118*0Sstevel@tonic-gate struct dns_res_target {
119*0Sstevel@tonic-gate 	struct dns_res_target *next;
120*0Sstevel@tonic-gate 	querybuf qbuf;		/* query buffer */
121*0Sstevel@tonic-gate 	u_char *answer;		/* buffer to put answer */
122*0Sstevel@tonic-gate 	int anslen;		/* size of answer buffer */
123*0Sstevel@tonic-gate 	int qclass, qtype;	/* class and type of query */
124*0Sstevel@tonic-gate 	int action;		/* condition whether query is really issued */
125*0Sstevel@tonic-gate 	char qname[MAXDNAME +1]; /* domain name */
126*0Sstevel@tonic-gate #if 0
127*0Sstevel@tonic-gate 	int n;			/* result length */
128*0Sstevel@tonic-gate #endif
129*0Sstevel@tonic-gate };
130*0Sstevel@tonic-gate enum {RESTGT_DOALWAYS, RESTGT_AFTERFAILURE, RESTGT_IGNORE};
131*0Sstevel@tonic-gate enum {RESQRY_SUCCESS, RESQRY_FAIL};
132*0Sstevel@tonic-gate 
133*0Sstevel@tonic-gate struct pvt {
134*0Sstevel@tonic-gate 	struct hostent	host;
135*0Sstevel@tonic-gate 	char *		h_addr_ptrs[MAXADDRS + 1];
136*0Sstevel@tonic-gate 	char *		host_aliases[MAXALIASES];
137*0Sstevel@tonic-gate 	char		hostbuf[8*1024];
138*0Sstevel@tonic-gate 	u_char		host_addr[16];	/* IPv4 or IPv6 */
139*0Sstevel@tonic-gate 	struct __res_state  *res;
140*0Sstevel@tonic-gate 	void		(*free_res)(void *);
141*0Sstevel@tonic-gate };
142*0Sstevel@tonic-gate 
143*0Sstevel@tonic-gate typedef union {
144*0Sstevel@tonic-gate 	int32_t al;
145*0Sstevel@tonic-gate 	char ac;
146*0Sstevel@tonic-gate } align;
147*0Sstevel@tonic-gate 
148*0Sstevel@tonic-gate static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
149*0Sstevel@tonic-gate static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };
150*0Sstevel@tonic-gate /* Note: the IPv6 loopback address is in the "tunnel" space */
151*0Sstevel@tonic-gate static const u_char v6local[] = { 0,0, 0,1 }; /* last 4 bytes of IPv6 addr */
152*0Sstevel@tonic-gate 
153*0Sstevel@tonic-gate /* Forwards. */
154*0Sstevel@tonic-gate 
155*0Sstevel@tonic-gate static void		ho_close(struct irs_ho *this);
156*0Sstevel@tonic-gate static struct hostent *	ho_byname(struct irs_ho *this, const char *name);
157*0Sstevel@tonic-gate static struct hostent *	ho_byname2(struct irs_ho *this, const char *name,
158*0Sstevel@tonic-gate 				   int af);
159*0Sstevel@tonic-gate static struct hostent *	ho_byaddr(struct irs_ho *this, const void *addr,
160*0Sstevel@tonic-gate 				  int len, int af);
161*0Sstevel@tonic-gate static struct hostent *	ho_next(struct irs_ho *this);
162*0Sstevel@tonic-gate static void		ho_rewind(struct irs_ho *this);
163*0Sstevel@tonic-gate static void		ho_minimize(struct irs_ho *this);
164*0Sstevel@tonic-gate static struct __res_state * ho_res_get(struct irs_ho *this);
165*0Sstevel@tonic-gate static void		ho_res_set(struct irs_ho *this,
166*0Sstevel@tonic-gate 				   struct __res_state *res,
167*0Sstevel@tonic-gate 				   void (*free_res)(void *));
168*0Sstevel@tonic-gate static struct addrinfo * ho_addrinfo(struct irs_ho *this, const char *name,
169*0Sstevel@tonic-gate 				     const struct addrinfo *pai);
170*0Sstevel@tonic-gate 
171*0Sstevel@tonic-gate static void		map_v4v6_hostent(struct hostent *hp, char **bp,
172*0Sstevel@tonic-gate 					 char *ep);
173*0Sstevel@tonic-gate static void		addrsort(res_state, char **, int);
174*0Sstevel@tonic-gate static struct hostent *	gethostans(struct irs_ho *this,
175*0Sstevel@tonic-gate 				   const u_char *ansbuf, int anslen,
176*0Sstevel@tonic-gate 				   const char *qname, int qtype,
177*0Sstevel@tonic-gate 				   int af, int size,
178*0Sstevel@tonic-gate 				   struct addrinfo **ret_aip,
179*0Sstevel@tonic-gate 				   const struct addrinfo *pai);
180*0Sstevel@tonic-gate static int add_hostent(struct pvt *pvt, char *bp, char **hap,
181*0Sstevel@tonic-gate 		       struct addrinfo *ai);
182*0Sstevel@tonic-gate static int		init(struct irs_ho *this);
183*0Sstevel@tonic-gate 
184*0Sstevel@tonic-gate /* Exports. */
185*0Sstevel@tonic-gate 
186*0Sstevel@tonic-gate struct irs_ho *
187*0Sstevel@tonic-gate irs_dns_ho(struct irs_acc *this) {
188*0Sstevel@tonic-gate 	struct irs_ho *ho;
189*0Sstevel@tonic-gate 	struct pvt *pvt;
190*0Sstevel@tonic-gate 
191*0Sstevel@tonic-gate 	UNUSED(this);
192*0Sstevel@tonic-gate 
193*0Sstevel@tonic-gate 	if (!(pvt = memget(sizeof *pvt))) {
194*0Sstevel@tonic-gate 		errno = ENOMEM;
195*0Sstevel@tonic-gate 		return (NULL);
196*0Sstevel@tonic-gate 	}
197*0Sstevel@tonic-gate 	memset(pvt, 0, sizeof *pvt);
198*0Sstevel@tonic-gate 
199*0Sstevel@tonic-gate 	if (!(ho = memget(sizeof *ho))) {
200*0Sstevel@tonic-gate 		memput(pvt, sizeof *pvt);
201*0Sstevel@tonic-gate 		errno = ENOMEM;
202*0Sstevel@tonic-gate 		return (NULL);
203*0Sstevel@tonic-gate 	}
204*0Sstevel@tonic-gate 	memset(ho, 0x5e, sizeof *ho);
205*0Sstevel@tonic-gate 	ho->private = pvt;
206*0Sstevel@tonic-gate 	ho->close = ho_close;
207*0Sstevel@tonic-gate 	ho->byname = ho_byname;
208*0Sstevel@tonic-gate 	ho->byname2 = ho_byname2;
209*0Sstevel@tonic-gate 	ho->byaddr = ho_byaddr;
210*0Sstevel@tonic-gate 	ho->next = ho_next;
211*0Sstevel@tonic-gate 	ho->rewind = ho_rewind;
212*0Sstevel@tonic-gate 	ho->minimize = ho_minimize;
213*0Sstevel@tonic-gate 	ho->res_get = ho_res_get;
214*0Sstevel@tonic-gate 	ho->res_set = ho_res_set;
215*0Sstevel@tonic-gate 	ho->addrinfo = ho_addrinfo;
216*0Sstevel@tonic-gate 	return (ho);
217*0Sstevel@tonic-gate }
218*0Sstevel@tonic-gate 
219*0Sstevel@tonic-gate /* Methods. */
220*0Sstevel@tonic-gate 
221*0Sstevel@tonic-gate static void
222*0Sstevel@tonic-gate ho_close(struct irs_ho *this) {
223*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
224*0Sstevel@tonic-gate 
225*0Sstevel@tonic-gate 	ho_minimize(this);
226*0Sstevel@tonic-gate 	if (pvt->res && pvt->free_res)
227*0Sstevel@tonic-gate 		(*pvt->free_res)(pvt->res);
228*0Sstevel@tonic-gate 	if (pvt)
229*0Sstevel@tonic-gate 		memput(pvt, sizeof *pvt);
230*0Sstevel@tonic-gate 	memput(this, sizeof *this);
231*0Sstevel@tonic-gate }
232*0Sstevel@tonic-gate 
233*0Sstevel@tonic-gate static struct hostent *
234*0Sstevel@tonic-gate ho_byname(struct irs_ho *this, const char *name) {
235*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
236*0Sstevel@tonic-gate 	struct hostent *hp;
237*0Sstevel@tonic-gate 
238*0Sstevel@tonic-gate 	if (init(this) == -1)
239*0Sstevel@tonic-gate 		return (NULL);
240*0Sstevel@tonic-gate 
241*0Sstevel@tonic-gate 	if (pvt->res->options & RES_USE_INET6) {
242*0Sstevel@tonic-gate 		hp = ho_byname2(this, name, AF_INET6);
243*0Sstevel@tonic-gate 		if (hp)
244*0Sstevel@tonic-gate 			return (hp);
245*0Sstevel@tonic-gate 	}
246*0Sstevel@tonic-gate 	return (ho_byname2(this, name, AF_INET));
247*0Sstevel@tonic-gate }
248*0Sstevel@tonic-gate 
249*0Sstevel@tonic-gate static struct hostent *
250*0Sstevel@tonic-gate ho_byname2(struct irs_ho *this, const char *name, int af)
251*0Sstevel@tonic-gate {
252*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
253*0Sstevel@tonic-gate 	struct hostent *hp = NULL;
254*0Sstevel@tonic-gate 	int n, size;
255*0Sstevel@tonic-gate 	char tmp[NS_MAXDNAME];
256*0Sstevel@tonic-gate 	const char *cp;
257*0Sstevel@tonic-gate 	struct addrinfo ai;
258*0Sstevel@tonic-gate 	struct dns_res_target *q, *p;
259*0Sstevel@tonic-gate 	int querystate = RESQRY_FAIL;
260*0Sstevel@tonic-gate 
261*0Sstevel@tonic-gate 	if (init(this) == -1)
262*0Sstevel@tonic-gate 		return (NULL);
263*0Sstevel@tonic-gate 
264*0Sstevel@tonic-gate 	q = memget(sizeof(*q));
265*0Sstevel@tonic-gate 	if (q == NULL) {
266*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
267*0Sstevel@tonic-gate 		errno = ENOMEM;
268*0Sstevel@tonic-gate 		goto cleanup;
269*0Sstevel@tonic-gate 	}
270*0Sstevel@tonic-gate 	memset(q, 0, sizeof(q));
271*0Sstevel@tonic-gate 
272*0Sstevel@tonic-gate 	switch (af) {
273*0Sstevel@tonic-gate 	case AF_INET:
274*0Sstevel@tonic-gate 		size = INADDRSZ;
275*0Sstevel@tonic-gate 		q->qclass = C_IN;
276*0Sstevel@tonic-gate 		q->qtype = T_A;
277*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
278*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
279*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
280*0Sstevel@tonic-gate 		break;
281*0Sstevel@tonic-gate 	case AF_INET6:
282*0Sstevel@tonic-gate 		size = IN6ADDRSZ;
283*0Sstevel@tonic-gate 		q->qclass = C_IN;
284*0Sstevel@tonic-gate 		q->qtype = T_AAAA;
285*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
286*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
287*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
288*0Sstevel@tonic-gate 		break;
289*0Sstevel@tonic-gate 	default:
290*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
291*0Sstevel@tonic-gate 		errno = EAFNOSUPPORT;
292*0Sstevel@tonic-gate 		hp = NULL;
293*0Sstevel@tonic-gate 		goto cleanup;
294*0Sstevel@tonic-gate 	}
295*0Sstevel@tonic-gate 
296*0Sstevel@tonic-gate 	/*
297*0Sstevel@tonic-gate 	 * if there aren't any dots, it could be a user-level alias.
298*0Sstevel@tonic-gate 	 * this is also done in res_nquery() since we are not the only
299*0Sstevel@tonic-gate 	 * function that looks up host names.
300*0Sstevel@tonic-gate 	 */
301*0Sstevel@tonic-gate 	if (!strchr(name, '.') && (cp = res_hostalias(pvt->res, name,
302*0Sstevel@tonic-gate 						      tmp, sizeof tmp)))
303*0Sstevel@tonic-gate 		name = cp;
304*0Sstevel@tonic-gate 
305*0Sstevel@tonic-gate 	for (p = q; p; p = p->next) {
306*0Sstevel@tonic-gate 		switch(p->action) {
307*0Sstevel@tonic-gate 		case RESTGT_DOALWAYS:
308*0Sstevel@tonic-gate 			break;
309*0Sstevel@tonic-gate 		case RESTGT_AFTERFAILURE:
310*0Sstevel@tonic-gate 			if (querystate == RESQRY_SUCCESS)
311*0Sstevel@tonic-gate 				continue;
312*0Sstevel@tonic-gate 			break;
313*0Sstevel@tonic-gate 		case RESTGT_IGNORE:
314*0Sstevel@tonic-gate 			continue;
315*0Sstevel@tonic-gate 		}
316*0Sstevel@tonic-gate 
317*0Sstevel@tonic-gate 		if ((n = res_nsearch(pvt->res, name, p->qclass, p->qtype,
318*0Sstevel@tonic-gate 				     p->answer, p->anslen)) < 0) {
319*0Sstevel@tonic-gate 			querystate = RESQRY_FAIL;
320*0Sstevel@tonic-gate 			continue;
321*0Sstevel@tonic-gate 		}
322*0Sstevel@tonic-gate 
323*0Sstevel@tonic-gate 		memset(&ai, 0, sizeof(ai));
324*0Sstevel@tonic-gate 		ai.ai_family = af;
325*0Sstevel@tonic-gate 		if ((hp = gethostans(this, p->answer, n, name, p->qtype,
326*0Sstevel@tonic-gate 				     af, size, NULL,
327*0Sstevel@tonic-gate 				     (const struct addrinfo *)&ai)) != NULL)
328*0Sstevel@tonic-gate 			goto cleanup;	/* no more loop is necessary */
329*0Sstevel@tonic-gate 
330*0Sstevel@tonic-gate 		querystate = RESQRY_FAIL;
331*0Sstevel@tonic-gate 		continue;
332*0Sstevel@tonic-gate 	}
333*0Sstevel@tonic-gate 
334*0Sstevel@tonic-gate  cleanup:
335*0Sstevel@tonic-gate 	if (q != NULL)
336*0Sstevel@tonic-gate 		memput(q, sizeof(*q));
337*0Sstevel@tonic-gate 	return(hp);
338*0Sstevel@tonic-gate }
339*0Sstevel@tonic-gate 
340*0Sstevel@tonic-gate static struct hostent *
341*0Sstevel@tonic-gate ho_byaddr(struct irs_ho *this, const void *addr, int len, int af)
342*0Sstevel@tonic-gate {
343*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
344*0Sstevel@tonic-gate 	const u_char *uaddr = addr;
345*0Sstevel@tonic-gate 	char *qp;
346*0Sstevel@tonic-gate 	struct hostent *hp = NULL;
347*0Sstevel@tonic-gate 	struct addrinfo ai;
348*0Sstevel@tonic-gate 	struct dns_res_target *q, *q2, *p;
349*0Sstevel@tonic-gate 	int n, size, i;
350*0Sstevel@tonic-gate 	int querystate = RESQRY_FAIL;
351*0Sstevel@tonic-gate 
352*0Sstevel@tonic-gate 	if (init(this) == -1)
353*0Sstevel@tonic-gate 		return (NULL);
354*0Sstevel@tonic-gate 
355*0Sstevel@tonic-gate 	q = memget(sizeof(*q));
356*0Sstevel@tonic-gate 	q2 = memget(sizeof(*q2));
357*0Sstevel@tonic-gate 	if (q == NULL || q2 == NULL) {
358*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
359*0Sstevel@tonic-gate 		errno = ENOMEM;
360*0Sstevel@tonic-gate 		goto cleanup;
361*0Sstevel@tonic-gate 	}
362*0Sstevel@tonic-gate 	memset(q, 0, sizeof(q));
363*0Sstevel@tonic-gate 	memset(q2, 0, sizeof(q2));
364*0Sstevel@tonic-gate 
365*0Sstevel@tonic-gate 	if (af == AF_INET6 && len == IN6ADDRSZ &&
366*0Sstevel@tonic-gate 	    (!memcmp(uaddr, mapped, sizeof mapped) ||
367*0Sstevel@tonic-gate            (!memcmp(uaddr, tunnelled, sizeof tunnelled) &&
368*0Sstevel@tonic-gate             memcmp(&uaddr[sizeof tunnelled], v6local, sizeof(v6local))))) {
369*0Sstevel@tonic-gate 		/* Unmap. */
370*0Sstevel@tonic-gate 		addr = (const char *)addr + sizeof mapped;
371*0Sstevel@tonic-gate 		uaddr += sizeof mapped;
372*0Sstevel@tonic-gate 		af = AF_INET;
373*0Sstevel@tonic-gate 		len = INADDRSZ;
374*0Sstevel@tonic-gate 	}
375*0Sstevel@tonic-gate 	switch (af) {
376*0Sstevel@tonic-gate 	case AF_INET:
377*0Sstevel@tonic-gate 		size = INADDRSZ;
378*0Sstevel@tonic-gate 		q->qclass = C_IN;
379*0Sstevel@tonic-gate 		q->qtype = T_PTR;
380*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
381*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
382*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
383*0Sstevel@tonic-gate 		break;
384*0Sstevel@tonic-gate 	case AF_INET6:
385*0Sstevel@tonic-gate 		size = IN6ADDRSZ;
386*0Sstevel@tonic-gate 		q->qclass = C_IN;
387*0Sstevel@tonic-gate 		q->qtype = T_PTR;
388*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
389*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
390*0Sstevel@tonic-gate 		q->next = q2;
391*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
392*0Sstevel@tonic-gate 		q2->qclass = C_IN;
393*0Sstevel@tonic-gate 		q2->qtype = T_PTR;
394*0Sstevel@tonic-gate 		q2->answer = q2->qbuf.buf;
395*0Sstevel@tonic-gate 		q2->anslen = sizeof(q2->qbuf);
396*0Sstevel@tonic-gate 		if ((pvt->res->options & RES_NO_NIBBLE2) != 0)
397*0Sstevel@tonic-gate 			q2->action = RESTGT_IGNORE;
398*0Sstevel@tonic-gate 		else
399*0Sstevel@tonic-gate 			q2->action = RESTGT_AFTERFAILURE;
400*0Sstevel@tonic-gate 		break;
401*0Sstevel@tonic-gate 	default:
402*0Sstevel@tonic-gate 		errno = EAFNOSUPPORT;
403*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
404*0Sstevel@tonic-gate 		hp = NULL;
405*0Sstevel@tonic-gate 		goto cleanup;
406*0Sstevel@tonic-gate 	}
407*0Sstevel@tonic-gate 	if (size > len) {
408*0Sstevel@tonic-gate 		errno = EINVAL;
409*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
410*0Sstevel@tonic-gate 		hp = NULL;
411*0Sstevel@tonic-gate 		goto cleanup;
412*0Sstevel@tonic-gate 	}
413*0Sstevel@tonic-gate 	switch (af) {
414*0Sstevel@tonic-gate 	case AF_INET:
415*0Sstevel@tonic-gate 		qp = q->qname;
416*0Sstevel@tonic-gate 		(void) sprintf(qp, "%u.%u.%u.%u.in-addr.arpa",
417*0Sstevel@tonic-gate 			       (uaddr[3] & 0xff),
418*0Sstevel@tonic-gate 			       (uaddr[2] & 0xff),
419*0Sstevel@tonic-gate 			       (uaddr[1] & 0xff),
420*0Sstevel@tonic-gate 			       (uaddr[0] & 0xff));
421*0Sstevel@tonic-gate 		break;
422*0Sstevel@tonic-gate 	case AF_INET6:
423*0Sstevel@tonic-gate 		if (q->action != RESTGT_IGNORE) {
424*0Sstevel@tonic-gate 			qp = q->qname;
425*0Sstevel@tonic-gate 			for (n = IN6ADDRSZ - 1; n >= 0; n--) {
426*0Sstevel@tonic-gate 				i = SPRINTF((qp, "%x.%x.",
427*0Sstevel@tonic-gate 					       uaddr[n] & 0xf,
428*0Sstevel@tonic-gate 					       (uaddr[n] >> 4) & 0xf));
429*0Sstevel@tonic-gate 				if (i < 0)
430*0Sstevel@tonic-gate 					abort();
431*0Sstevel@tonic-gate 				qp += i;
432*0Sstevel@tonic-gate 			}
433*0Sstevel@tonic-gate #ifdef HAVE_STRLCAT
434*0Sstevel@tonic-gate 			strlcat(q->qname, res_get_nibblesuffix(pvt->res),
435*0Sstevel@tonic-gate 			    sizeof(q->qname));
436*0Sstevel@tonic-gate #else
437*0Sstevel@tonic-gate 			strcpy(qp, res_get_nibblesuffix(pvt->res));
438*0Sstevel@tonic-gate #endif
439*0Sstevel@tonic-gate 		}
440*0Sstevel@tonic-gate 		if (q2->action != RESTGT_IGNORE) {
441*0Sstevel@tonic-gate 			qp = q2->qname;
442*0Sstevel@tonic-gate 			for (n = IN6ADDRSZ - 1; n >= 0; n--) {
443*0Sstevel@tonic-gate 				i = SPRINTF((qp, "%x.%x.",
444*0Sstevel@tonic-gate 					       uaddr[n] & 0xf,
445*0Sstevel@tonic-gate 					       (uaddr[n] >> 4) & 0xf));
446*0Sstevel@tonic-gate 				if (i < 0)
447*0Sstevel@tonic-gate 					abort();
448*0Sstevel@tonic-gate 				qp += i;
449*0Sstevel@tonic-gate 			}
450*0Sstevel@tonic-gate #ifdef HAVE_STRLCAT
451*0Sstevel@tonic-gate 			strlcat(q->qname, res_get_nibblesuffix2(pvt->res),
452*0Sstevel@tonic-gate 			    sizeof(q->qname));
453*0Sstevel@tonic-gate #else
454*0Sstevel@tonic-gate 			strcpy(qp, res_get_nibblesuffix2(pvt->res));
455*0Sstevel@tonic-gate #endif
456*0Sstevel@tonic-gate 		}
457*0Sstevel@tonic-gate 		break;
458*0Sstevel@tonic-gate 	default:
459*0Sstevel@tonic-gate 		abort();
460*0Sstevel@tonic-gate 	}
461*0Sstevel@tonic-gate 
462*0Sstevel@tonic-gate 	for (p = q; p; p = p->next) {
463*0Sstevel@tonic-gate 		switch(p->action) {
464*0Sstevel@tonic-gate 		case RESTGT_DOALWAYS:
465*0Sstevel@tonic-gate 			break;
466*0Sstevel@tonic-gate 		case RESTGT_AFTERFAILURE:
467*0Sstevel@tonic-gate 			if (querystate == RESQRY_SUCCESS)
468*0Sstevel@tonic-gate 				continue;
469*0Sstevel@tonic-gate 			break;
470*0Sstevel@tonic-gate 		case RESTGT_IGNORE:
471*0Sstevel@tonic-gate 			continue;
472*0Sstevel@tonic-gate 		}
473*0Sstevel@tonic-gate 
474*0Sstevel@tonic-gate 		if ((n = res_nquery(pvt->res, p->qname, p->qclass, p->qtype,
475*0Sstevel@tonic-gate 				    p->answer, p->anslen)) < 0) {
476*0Sstevel@tonic-gate 			querystate = RESQRY_FAIL;
477*0Sstevel@tonic-gate 			continue;
478*0Sstevel@tonic-gate 		}
479*0Sstevel@tonic-gate 
480*0Sstevel@tonic-gate 		memset(&ai, 0, sizeof(ai));
481*0Sstevel@tonic-gate 		ai.ai_family = af;
482*0Sstevel@tonic-gate 		hp = gethostans(this, p->answer, n, p->qname, T_PTR, af, size,
483*0Sstevel@tonic-gate 				NULL, (const struct addrinfo *)&ai);
484*0Sstevel@tonic-gate 		if (!hp) {
485*0Sstevel@tonic-gate 			querystate = RESQRY_FAIL;
486*0Sstevel@tonic-gate 			continue;
487*0Sstevel@tonic-gate 		}
488*0Sstevel@tonic-gate 
489*0Sstevel@tonic-gate 		memcpy(pvt->host_addr, addr, len);
490*0Sstevel@tonic-gate 		pvt->h_addr_ptrs[0] = (char *)pvt->host_addr;
491*0Sstevel@tonic-gate 		pvt->h_addr_ptrs[1] = NULL;
492*0Sstevel@tonic-gate 		if (af == AF_INET && (pvt->res->options & RES_USE_INET6)) {
493*0Sstevel@tonic-gate 			map_v4v6_address((char*)pvt->host_addr,
494*0Sstevel@tonic-gate 					 (char*)pvt->host_addr);
495*0Sstevel@tonic-gate 			pvt->host.h_addrtype = AF_INET6;
496*0Sstevel@tonic-gate 			pvt->host.h_length = IN6ADDRSZ;
497*0Sstevel@tonic-gate 		}
498*0Sstevel@tonic-gate 
499*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_SUCCESS);
500*0Sstevel@tonic-gate 		goto cleanup;	/* no more loop is necessary. */
501*0Sstevel@tonic-gate 	}
502*0Sstevel@tonic-gate 	hp = NULL; /* H_ERRNO was set by subroutines */
503*0Sstevel@tonic-gate 
504*0Sstevel@tonic-gate  cleanup:
505*0Sstevel@tonic-gate 	if (q != NULL)
506*0Sstevel@tonic-gate 		memput(q, sizeof(*q));
507*0Sstevel@tonic-gate 	if (q2 != NULL)
508*0Sstevel@tonic-gate 		memput(q2, sizeof(*q2));
509*0Sstevel@tonic-gate 	return(hp);
510*0Sstevel@tonic-gate }
511*0Sstevel@tonic-gate 
512*0Sstevel@tonic-gate static struct hostent *
513*0Sstevel@tonic-gate ho_next(struct irs_ho *this) {
514*0Sstevel@tonic-gate 
515*0Sstevel@tonic-gate 	UNUSED(this);
516*0Sstevel@tonic-gate 
517*0Sstevel@tonic-gate 	return (NULL);
518*0Sstevel@tonic-gate }
519*0Sstevel@tonic-gate 
520*0Sstevel@tonic-gate static void
521*0Sstevel@tonic-gate ho_rewind(struct irs_ho *this) {
522*0Sstevel@tonic-gate 
523*0Sstevel@tonic-gate 	UNUSED(this);
524*0Sstevel@tonic-gate 
525*0Sstevel@tonic-gate 	/* NOOP */
526*0Sstevel@tonic-gate }
527*0Sstevel@tonic-gate 
528*0Sstevel@tonic-gate static void
529*0Sstevel@tonic-gate ho_minimize(struct irs_ho *this) {
530*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
531*0Sstevel@tonic-gate 
532*0Sstevel@tonic-gate 	if (pvt->res)
533*0Sstevel@tonic-gate 		res_nclose(pvt->res);
534*0Sstevel@tonic-gate }
535*0Sstevel@tonic-gate 
536*0Sstevel@tonic-gate static struct __res_state *
537*0Sstevel@tonic-gate ho_res_get(struct irs_ho *this) {
538*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
539*0Sstevel@tonic-gate 
540*0Sstevel@tonic-gate 	if (!pvt->res) {
541*0Sstevel@tonic-gate 		struct __res_state *res;
542*0Sstevel@tonic-gate 		res = (struct __res_state *)malloc(sizeof *res);
543*0Sstevel@tonic-gate 		if (!res) {
544*0Sstevel@tonic-gate 			errno = ENOMEM;
545*0Sstevel@tonic-gate 			return (NULL);
546*0Sstevel@tonic-gate 		}
547*0Sstevel@tonic-gate 		memset(res, 0, sizeof *res);
548*0Sstevel@tonic-gate 		ho_res_set(this, res, free);
549*0Sstevel@tonic-gate 	}
550*0Sstevel@tonic-gate 
551*0Sstevel@tonic-gate 	return (pvt->res);
552*0Sstevel@tonic-gate }
553*0Sstevel@tonic-gate 
554*0Sstevel@tonic-gate /* XXX */
555*0Sstevel@tonic-gate extern struct addrinfo *addr2addrinfo __P((const struct addrinfo *,
556*0Sstevel@tonic-gate 					   const char *));
557*0Sstevel@tonic-gate 
558*0Sstevel@tonic-gate static struct addrinfo *
559*0Sstevel@tonic-gate ho_addrinfo(struct irs_ho *this, const char *name, const struct addrinfo *pai)
560*0Sstevel@tonic-gate {
561*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
562*0Sstevel@tonic-gate 	int n;
563*0Sstevel@tonic-gate 	char tmp[NS_MAXDNAME];
564*0Sstevel@tonic-gate 	const char *cp;
565*0Sstevel@tonic-gate 	struct dns_res_target *q, *q2, *p;
566*0Sstevel@tonic-gate 	struct addrinfo sentinel, *cur;
567*0Sstevel@tonic-gate 	int querystate = RESQRY_FAIL;
568*0Sstevel@tonic-gate 
569*0Sstevel@tonic-gate 	if (init(this) == -1)
570*0Sstevel@tonic-gate 		return (NULL);
571*0Sstevel@tonic-gate 
572*0Sstevel@tonic-gate 	memset(&sentinel, 0, sizeof(sentinel));
573*0Sstevel@tonic-gate 	cur = &sentinel;
574*0Sstevel@tonic-gate 
575*0Sstevel@tonic-gate 	q = memget(sizeof(*q));
576*0Sstevel@tonic-gate 	q2 = memget(sizeof(*q2));
577*0Sstevel@tonic-gate 	if (q == NULL || q2 == NULL) {
578*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
579*0Sstevel@tonic-gate 		errno = ENOMEM;
580*0Sstevel@tonic-gate 		goto cleanup;
581*0Sstevel@tonic-gate 	}
582*0Sstevel@tonic-gate 	memset(q, 0, sizeof(q2));
583*0Sstevel@tonic-gate 	memset(q2, 0, sizeof(q2));
584*0Sstevel@tonic-gate 
585*0Sstevel@tonic-gate 	switch (pai->ai_family) {
586*0Sstevel@tonic-gate 	case AF_UNSPEC:
587*0Sstevel@tonic-gate 		/* prefer IPv6 */
588*0Sstevel@tonic-gate 		q->qclass = C_IN;
589*0Sstevel@tonic-gate 		q->qtype = T_AAAA;
590*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
591*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
592*0Sstevel@tonic-gate 		q->next = q2;
593*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
594*0Sstevel@tonic-gate 		q2->qclass = C_IN;
595*0Sstevel@tonic-gate 		q2->qtype = T_A;
596*0Sstevel@tonic-gate 		q2->answer = q2->qbuf.buf;
597*0Sstevel@tonic-gate 		q2->anslen = sizeof(q2->qbuf);
598*0Sstevel@tonic-gate 		q2->action = RESTGT_DOALWAYS;
599*0Sstevel@tonic-gate 		break;
600*0Sstevel@tonic-gate 	case AF_INET:
601*0Sstevel@tonic-gate 		q->qclass = C_IN;
602*0Sstevel@tonic-gate 		q->qtype = T_A;
603*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
604*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
605*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
606*0Sstevel@tonic-gate 		break;
607*0Sstevel@tonic-gate 	case AF_INET6:
608*0Sstevel@tonic-gate 		q->qclass = C_IN;
609*0Sstevel@tonic-gate 		q->qtype = T_AAAA;
610*0Sstevel@tonic-gate 		q->answer = q->qbuf.buf;
611*0Sstevel@tonic-gate 		q->anslen = sizeof(q->qbuf);
612*0Sstevel@tonic-gate 		q->action = RESTGT_DOALWAYS;
613*0Sstevel@tonic-gate 		break;
614*0Sstevel@tonic-gate 	default:
615*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NO_RECOVERY); /* better error? */
616*0Sstevel@tonic-gate 		goto cleanup;
617*0Sstevel@tonic-gate 	}
618*0Sstevel@tonic-gate 
619*0Sstevel@tonic-gate 	/*
620*0Sstevel@tonic-gate 	 * if there aren't any dots, it could be a user-level alias.
621*0Sstevel@tonic-gate 	 * this is also done in res_nquery() since we are not the only
622*0Sstevel@tonic-gate 	 * function that looks up host names.
623*0Sstevel@tonic-gate 	 */
624*0Sstevel@tonic-gate 	if (!strchr(name, '.') && (cp = res_hostalias(pvt->res, name,
625*0Sstevel@tonic-gate 						      tmp, sizeof tmp)))
626*0Sstevel@tonic-gate 		name = cp;
627*0Sstevel@tonic-gate 
628*0Sstevel@tonic-gate 	for (p = q; p; p = p->next) {
629*0Sstevel@tonic-gate 		struct addrinfo *ai;
630*0Sstevel@tonic-gate 
631*0Sstevel@tonic-gate 		switch(p->action) {
632*0Sstevel@tonic-gate 		case RESTGT_DOALWAYS:
633*0Sstevel@tonic-gate 			break;
634*0Sstevel@tonic-gate 		case RESTGT_AFTERFAILURE:
635*0Sstevel@tonic-gate 			if (querystate == RESQRY_SUCCESS)
636*0Sstevel@tonic-gate 				continue;
637*0Sstevel@tonic-gate 			break;
638*0Sstevel@tonic-gate 		case RESTGT_IGNORE:
639*0Sstevel@tonic-gate 			continue;
640*0Sstevel@tonic-gate 		}
641*0Sstevel@tonic-gate 
642*0Sstevel@tonic-gate 		if ((n = res_nsearch(pvt->res, name, p->qclass, p->qtype,
643*0Sstevel@tonic-gate 				     p->answer, p->anslen)) < 0) {
644*0Sstevel@tonic-gate 			querystate = RESQRY_FAIL;
645*0Sstevel@tonic-gate 			continue;
646*0Sstevel@tonic-gate 		}
647*0Sstevel@tonic-gate 		(void)gethostans(this, p->answer, n, name, p->qtype,
648*0Sstevel@tonic-gate 				 pai->ai_family, /* XXX: meaningless */
649*0Sstevel@tonic-gate 				 0, &ai, pai);
650*0Sstevel@tonic-gate 		if (ai) {
651*0Sstevel@tonic-gate 			querystate = RESQRY_SUCCESS;
652*0Sstevel@tonic-gate 			cur->ai_next = ai;
653*0Sstevel@tonic-gate 			while (cur && cur->ai_next)
654*0Sstevel@tonic-gate 				cur = cur->ai_next;
655*0Sstevel@tonic-gate 		}
656*0Sstevel@tonic-gate 		else
657*0Sstevel@tonic-gate 			querystate = RESQRY_FAIL;
658*0Sstevel@tonic-gate 	}
659*0Sstevel@tonic-gate 
660*0Sstevel@tonic-gate  cleanup:
661*0Sstevel@tonic-gate 	if (q != NULL)
662*0Sstevel@tonic-gate 		memput(q, sizeof(*q));
663*0Sstevel@tonic-gate 	if (q2 != NULL)
664*0Sstevel@tonic-gate 		memput(q2, sizeof(*q2));
665*0Sstevel@tonic-gate 	return(sentinel.ai_next);
666*0Sstevel@tonic-gate }
667*0Sstevel@tonic-gate 
668*0Sstevel@tonic-gate static void
669*0Sstevel@tonic-gate ho_res_set(struct irs_ho *this, struct __res_state *res,
670*0Sstevel@tonic-gate 		void (*free_res)(void *)) {
671*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
672*0Sstevel@tonic-gate 
673*0Sstevel@tonic-gate 	if (pvt->res && pvt->free_res) {
674*0Sstevel@tonic-gate 		res_nclose(pvt->res);
675*0Sstevel@tonic-gate 		(*pvt->free_res)(pvt->res);
676*0Sstevel@tonic-gate 	}
677*0Sstevel@tonic-gate 
678*0Sstevel@tonic-gate 	pvt->res = res;
679*0Sstevel@tonic-gate 	pvt->free_res = free_res;
680*0Sstevel@tonic-gate }
681*0Sstevel@tonic-gate 
682*0Sstevel@tonic-gate /* Private. */
683*0Sstevel@tonic-gate 
684*0Sstevel@tonic-gate static struct hostent *
685*0Sstevel@tonic-gate gethostans(struct irs_ho *this,
686*0Sstevel@tonic-gate 	   const u_char *ansbuf, int anslen, const char *qname, int qtype,
687*0Sstevel@tonic-gate 	   int af, int size,	/* meaningless for addrinfo cases */
688*0Sstevel@tonic-gate 	   struct addrinfo **ret_aip, const struct addrinfo *pai)
689*0Sstevel@tonic-gate {
690*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
691*0Sstevel@tonic-gate 	int type, class, ancount, qdcount, n, haveanswer, had_error;
692*0Sstevel@tonic-gate 	int error = NETDB_SUCCESS, arcount;
693*0Sstevel@tonic-gate 	int (*name_ok)(const char *);
694*0Sstevel@tonic-gate 	const HEADER *hp;
695*0Sstevel@tonic-gate 	const u_char *eom;
696*0Sstevel@tonic-gate 	const u_char *eor;
697*0Sstevel@tonic-gate 	const u_char *cp;
698*0Sstevel@tonic-gate 	const char *tname;
699*0Sstevel@tonic-gate 	const char *hname;
700*0Sstevel@tonic-gate 	char *bp, *ep, **ap, **hap;
701*0Sstevel@tonic-gate 	char tbuf[MAXDNAME+1];
702*0Sstevel@tonic-gate 	struct addrinfo sentinel, *cur, ai;
703*0Sstevel@tonic-gate 
704*0Sstevel@tonic-gate 	if (pai == NULL) abort();
705*0Sstevel@tonic-gate 	if (ret_aip != NULL)
706*0Sstevel@tonic-gate 		*ret_aip = NULL;
707*0Sstevel@tonic-gate 	memset(&sentinel, 0, sizeof(sentinel));
708*0Sstevel@tonic-gate 	cur = &sentinel;
709*0Sstevel@tonic-gate 
710*0Sstevel@tonic-gate 	tname = qname;
711*0Sstevel@tonic-gate 	eom = ansbuf + anslen;
712*0Sstevel@tonic-gate 	switch (qtype) {
713*0Sstevel@tonic-gate 	case T_A:
714*0Sstevel@tonic-gate 	case T_AAAA:
715*0Sstevel@tonic-gate 	case T_ANY:	/* use T_ANY only for T_A/T_AAAA lookup */
716*0Sstevel@tonic-gate 		name_ok = res_hnok;
717*0Sstevel@tonic-gate 		break;
718*0Sstevel@tonic-gate 	case T_PTR:
719*0Sstevel@tonic-gate 		name_ok = res_dnok;
720*0Sstevel@tonic-gate 		break;
721*0Sstevel@tonic-gate 	default:
722*0Sstevel@tonic-gate 		abort();
723*0Sstevel@tonic-gate 	}
724*0Sstevel@tonic-gate 
725*0Sstevel@tonic-gate 	pvt->host.h_addrtype = af;
726*0Sstevel@tonic-gate 	pvt->host.h_length = size;
727*0Sstevel@tonic-gate 	hname = pvt->host.h_name = NULL;
728*0Sstevel@tonic-gate 
729*0Sstevel@tonic-gate 	/*
730*0Sstevel@tonic-gate 	 * Find first satisfactory answer.
731*0Sstevel@tonic-gate 	 */
732*0Sstevel@tonic-gate 	if (ansbuf + HFIXEDSZ > eom) {
733*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
734*0Sstevel@tonic-gate 		return (NULL);
735*0Sstevel@tonic-gate 	}
736*0Sstevel@tonic-gate 	hp = (const HEADER *)ansbuf;
737*0Sstevel@tonic-gate 	ancount = ntohs(hp->ancount);
738*0Sstevel@tonic-gate 	qdcount = ntohs(hp->qdcount);
739*0Sstevel@tonic-gate 	arcount = ntohs(hp->arcount);
740*0Sstevel@tonic-gate 	bp = pvt->hostbuf;
741*0Sstevel@tonic-gate 	ep = pvt->hostbuf + sizeof(pvt->hostbuf);
742*0Sstevel@tonic-gate 	cp = ansbuf + HFIXEDSZ;
743*0Sstevel@tonic-gate 	if (qdcount != 1) {
744*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
745*0Sstevel@tonic-gate 		return (NULL);
746*0Sstevel@tonic-gate 	}
747*0Sstevel@tonic-gate 	n = dn_expand(ansbuf, eom, cp, bp, ep - bp);
748*0Sstevel@tonic-gate 	if (n < 0 || !maybe_ok(pvt->res, bp, name_ok)) {
749*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
750*0Sstevel@tonic-gate 		return (NULL);
751*0Sstevel@tonic-gate 	}
752*0Sstevel@tonic-gate 	cp += n + QFIXEDSZ;
753*0Sstevel@tonic-gate 	if (cp > eom) {
754*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
755*0Sstevel@tonic-gate 		return (NULL);
756*0Sstevel@tonic-gate 	}
757*0Sstevel@tonic-gate 	if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
758*0Sstevel@tonic-gate 		/* res_nsend() has already verified that the query name is the
759*0Sstevel@tonic-gate 		 * same as the one we sent; this just gets the expanded name
760*0Sstevel@tonic-gate 		 * (i.e., with the succeeding search-domain tacked on).
761*0Sstevel@tonic-gate 		 */
762*0Sstevel@tonic-gate 		n = strlen(bp) + 1;		/* for the \0 */
763*0Sstevel@tonic-gate 		if (n > MAXHOSTNAMELEN) {
764*0Sstevel@tonic-gate 			RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
765*0Sstevel@tonic-gate 			return (NULL);
766*0Sstevel@tonic-gate 		}
767*0Sstevel@tonic-gate 		pvt->host.h_name = bp;
768*0Sstevel@tonic-gate 		hname = bp;
769*0Sstevel@tonic-gate 		bp += n;
770*0Sstevel@tonic-gate 		/* The qname can be abbreviated, but hname is now absolute. */
771*0Sstevel@tonic-gate 		qname = pvt->host.h_name;
772*0Sstevel@tonic-gate 	}
773*0Sstevel@tonic-gate 	ap = pvt->host_aliases;
774*0Sstevel@tonic-gate 	*ap = NULL;
775*0Sstevel@tonic-gate 	pvt->host.h_aliases = pvt->host_aliases;
776*0Sstevel@tonic-gate 	hap = pvt->h_addr_ptrs;
777*0Sstevel@tonic-gate 	*hap = NULL;
778*0Sstevel@tonic-gate 	pvt->host.h_addr_list = pvt->h_addr_ptrs;
779*0Sstevel@tonic-gate 	haveanswer = 0;
780*0Sstevel@tonic-gate 	had_error = 0;
781*0Sstevel@tonic-gate 	while (ancount-- > 0 && cp < eom && !had_error) {
782*0Sstevel@tonic-gate 		n = dn_expand(ansbuf, eom, cp, bp, ep - bp);
783*0Sstevel@tonic-gate 		if (n < 0 || !maybe_ok(pvt->res, bp, name_ok)) {
784*0Sstevel@tonic-gate 			had_error++;
785*0Sstevel@tonic-gate 			continue;
786*0Sstevel@tonic-gate 		}
787*0Sstevel@tonic-gate 		cp += n;			/* name */
788*0Sstevel@tonic-gate 		BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ);
789*0Sstevel@tonic-gate 		type = ns_get16(cp);
790*0Sstevel@tonic-gate  		cp += INT16SZ;			/* type */
791*0Sstevel@tonic-gate 		class = ns_get16(cp);
792*0Sstevel@tonic-gate  		cp += INT16SZ + INT32SZ;	/* class, TTL */
793*0Sstevel@tonic-gate 		n = ns_get16(cp);
794*0Sstevel@tonic-gate 		cp += INT16SZ;			/* len */
795*0Sstevel@tonic-gate 		BOUNDS_CHECK(cp, n);
796*0Sstevel@tonic-gate 		if (class != C_IN) {
797*0Sstevel@tonic-gate 			cp += n;
798*0Sstevel@tonic-gate 			continue;
799*0Sstevel@tonic-gate 		}
800*0Sstevel@tonic-gate 		eor = cp + n;
801*0Sstevel@tonic-gate 		if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
802*0Sstevel@tonic-gate 		    type == T_CNAME) {
803*0Sstevel@tonic-gate 			if (haveanswer) {
804*0Sstevel@tonic-gate 				int level = LOG_CRIT;
805*0Sstevel@tonic-gate #ifdef LOG_SECURITY
806*0Sstevel@tonic-gate 				level |= LOG_SECURITY;
807*0Sstevel@tonic-gate #endif
808*0Sstevel@tonic-gate 				syslog(level,
809*0Sstevel@tonic-gate  "gethostans: possible attempt to exploit buffer overflow while looking up %s",
810*0Sstevel@tonic-gate 					*qname ? qname : ".");
811*0Sstevel@tonic-gate 			}
812*0Sstevel@tonic-gate 			n = dn_expand(ansbuf, eor, cp, tbuf, sizeof tbuf);
813*0Sstevel@tonic-gate 			if (n < 0 || !maybe_ok(pvt->res, tbuf, name_ok)) {
814*0Sstevel@tonic-gate 				had_error++;
815*0Sstevel@tonic-gate 				continue;
816*0Sstevel@tonic-gate 			}
817*0Sstevel@tonic-gate 			cp += n;
818*0Sstevel@tonic-gate 			/* Store alias. */
819*0Sstevel@tonic-gate 			if (ap >= &pvt->host_aliases[MAXALIASES-1])
820*0Sstevel@tonic-gate 				continue;
821*0Sstevel@tonic-gate 			*ap++ = bp;
822*0Sstevel@tonic-gate 			n = strlen(bp) + 1;	/* for the \0 */
823*0Sstevel@tonic-gate 			bp += n;
824*0Sstevel@tonic-gate 			/* Get canonical name. */
825*0Sstevel@tonic-gate 			n = strlen(tbuf) + 1;	/* for the \0 */
826*0Sstevel@tonic-gate 			if (n > (ep - bp) || n > MAXHOSTNAMELEN) {
827*0Sstevel@tonic-gate 				had_error++;
828*0Sstevel@tonic-gate 				continue;
829*0Sstevel@tonic-gate 			}
830*0Sstevel@tonic-gate #ifdef HAVE_STRLCPY
831*0Sstevel@tonic-gate 			strlcpy(bp, tbuf, ep - bp);
832*0Sstevel@tonic-gate #else
833*0Sstevel@tonic-gate 			strcpy(bp, tbuf);
834*0Sstevel@tonic-gate #endif
835*0Sstevel@tonic-gate 			pvt->host.h_name = bp;
836*0Sstevel@tonic-gate 			hname = bp;
837*0Sstevel@tonic-gate 			bp += n;
838*0Sstevel@tonic-gate 			continue;
839*0Sstevel@tonic-gate 		}
840*0Sstevel@tonic-gate 		if (qtype == T_PTR && type == T_CNAME) {
841*0Sstevel@tonic-gate 			n = dn_expand(ansbuf, eor, cp, tbuf, sizeof tbuf);
842*0Sstevel@tonic-gate 			if (n < 0 || !maybe_dnok(pvt->res, tbuf)) {
843*0Sstevel@tonic-gate 				had_error++;
844*0Sstevel@tonic-gate 				continue;
845*0Sstevel@tonic-gate 			}
846*0Sstevel@tonic-gate 			cp += n;
847*0Sstevel@tonic-gate #ifdef RES_USE_DNAME
848*0Sstevel@tonic-gate 			if ((pvt->res->options & RES_USE_DNAME) != 0)
849*0Sstevel@tonic-gate #endif
850*0Sstevel@tonic-gate 			{
851*0Sstevel@tonic-gate 				/*
852*0Sstevel@tonic-gate 				 * We may be able to check this regardless
853*0Sstevel@tonic-gate 				 * of the USE_DNAME bit, but we add the check
854*0Sstevel@tonic-gate 				 * for now since the DNAME support is
855*0Sstevel@tonic-gate 				 * experimental.
856*0Sstevel@tonic-gate 				 */
857*0Sstevel@tonic-gate 				if (ns_samename(tname, bp) != 1)
858*0Sstevel@tonic-gate 					continue;
859*0Sstevel@tonic-gate 			}
860*0Sstevel@tonic-gate 			/* Get canonical name. */
861*0Sstevel@tonic-gate 			n = strlen(tbuf) + 1;	/* for the \0 */
862*0Sstevel@tonic-gate 			if (n > (ep - bp)) {
863*0Sstevel@tonic-gate 				had_error++;
864*0Sstevel@tonic-gate 				continue;
865*0Sstevel@tonic-gate 			}
866*0Sstevel@tonic-gate #ifdef HAVE_STRLCPY
867*0Sstevel@tonic-gate 			strlcpy(bp, tbuf, ep - bp);
868*0Sstevel@tonic-gate #else
869*0Sstevel@tonic-gate 			strcpy(bp, tbuf);
870*0Sstevel@tonic-gate #endif
871*0Sstevel@tonic-gate 			tname = bp;
872*0Sstevel@tonic-gate 			bp += n;
873*0Sstevel@tonic-gate 			continue;
874*0Sstevel@tonic-gate 		}
875*0Sstevel@tonic-gate 		if (qtype == T_ANY) {
876*0Sstevel@tonic-gate 			if (!(type == T_A || type == T_AAAA)) {
877*0Sstevel@tonic-gate 				cp += n;
878*0Sstevel@tonic-gate 				continue;
879*0Sstevel@tonic-gate 			}
880*0Sstevel@tonic-gate 		} else if (type != qtype) {
881*0Sstevel@tonic-gate 			cp += n;
882*0Sstevel@tonic-gate 			continue;
883*0Sstevel@tonic-gate 		}
884*0Sstevel@tonic-gate 		switch (type) {
885*0Sstevel@tonic-gate 		case T_PTR:
886*0Sstevel@tonic-gate 			if (ret_aip != NULL) {
887*0Sstevel@tonic-gate 				/* addrinfo never needs T_PTR */
888*0Sstevel@tonic-gate 				cp += n;
889*0Sstevel@tonic-gate 				continue;
890*0Sstevel@tonic-gate 			}
891*0Sstevel@tonic-gate 			if (ns_samename(tname, bp) != 1) {
892*0Sstevel@tonic-gate 				cp += n;
893*0Sstevel@tonic-gate 				continue;
894*0Sstevel@tonic-gate 			}
895*0Sstevel@tonic-gate 			n = dn_expand(ansbuf, eor, cp, bp, ep - bp);
896*0Sstevel@tonic-gate 			if (n < 0 || !maybe_hnok(pvt->res, bp) ||
897*0Sstevel@tonic-gate 			    n >= MAXHOSTNAMELEN) {
898*0Sstevel@tonic-gate 				had_error++;
899*0Sstevel@tonic-gate 				break;
900*0Sstevel@tonic-gate 			}
901*0Sstevel@tonic-gate 			cp += n;
902*0Sstevel@tonic-gate 			if (!haveanswer) {
903*0Sstevel@tonic-gate 				pvt->host.h_name = bp;
904*0Sstevel@tonic-gate 				hname = bp;
905*0Sstevel@tonic-gate 			}
906*0Sstevel@tonic-gate 			else if (ap < &pvt->host_aliases[MAXALIASES-1])
907*0Sstevel@tonic-gate 				*ap++ = bp;
908*0Sstevel@tonic-gate 			else
909*0Sstevel@tonic-gate 				n = -1;
910*0Sstevel@tonic-gate 			if (n != -1) {
911*0Sstevel@tonic-gate 				n = strlen(bp) + 1;	/* for the \0 */
912*0Sstevel@tonic-gate 				bp += n;
913*0Sstevel@tonic-gate 			}
914*0Sstevel@tonic-gate 			break;
915*0Sstevel@tonic-gate 		case T_A:
916*0Sstevel@tonic-gate 		case T_AAAA:
917*0Sstevel@tonic-gate 			if (ns_samename(hname, bp) != 1) {
918*0Sstevel@tonic-gate 				cp += n;
919*0Sstevel@tonic-gate 				continue;
920*0Sstevel@tonic-gate 			}
921*0Sstevel@tonic-gate 			if (type == T_A && n != INADDRSZ) {
922*0Sstevel@tonic-gate 				cp += n;
923*0Sstevel@tonic-gate 				continue;
924*0Sstevel@tonic-gate 			}
925*0Sstevel@tonic-gate 			if (type == T_AAAA && n != IN6ADDRSZ) {
926*0Sstevel@tonic-gate 				cp += n;
927*0Sstevel@tonic-gate 				continue;
928*0Sstevel@tonic-gate 			}
929*0Sstevel@tonic-gate 
930*0Sstevel@tonic-gate 			/* make addrinfo. don't overwrite constant PAI */
931*0Sstevel@tonic-gate 			ai = *pai;
932*0Sstevel@tonic-gate 			ai.ai_family = (type == T_AAAA) ? AF_INET6 : AF_INET;
933*0Sstevel@tonic-gate 			cur->ai_next = addr2addrinfo(
934*0Sstevel@tonic-gate 					(const struct addrinfo *)&ai,
935*0Sstevel@tonic-gate 					(const char *)cp);
936*0Sstevel@tonic-gate 			if (cur->ai_next == NULL)
937*0Sstevel@tonic-gate 				had_error++;
938*0Sstevel@tonic-gate 
939*0Sstevel@tonic-gate 			if (!haveanswer) {
940*0Sstevel@tonic-gate 				int nn;
941*0Sstevel@tonic-gate 
942*0Sstevel@tonic-gate 				nn = strlen(bp) + 1;	/* for the \0 */
943*0Sstevel@tonic-gate 				if (nn >= MAXHOSTNAMELEN) {
944*0Sstevel@tonic-gate 					cp += n;
945*0Sstevel@tonic-gate 					had_error++;
946*0Sstevel@tonic-gate 					continue;
947*0Sstevel@tonic-gate 				}
948*0Sstevel@tonic-gate 				pvt->host.h_name = bp;
949*0Sstevel@tonic-gate 				hname = bp;
950*0Sstevel@tonic-gate 				bp += nn;
951*0Sstevel@tonic-gate 			}
952*0Sstevel@tonic-gate 			/* Ensure alignment. */
953*0Sstevel@tonic-gate 			bp = (char *)(((u_long)bp + (sizeof(align) - 1)) &
954*0Sstevel@tonic-gate 				      ~(sizeof(align) - 1));
955*0Sstevel@tonic-gate 			/* Avoid overflows. */
956*0Sstevel@tonic-gate 			if (bp + n >= &pvt->hostbuf[sizeof pvt->hostbuf]) {
957*0Sstevel@tonic-gate 				had_error++;
958*0Sstevel@tonic-gate 				continue;
959*0Sstevel@tonic-gate 			}
960*0Sstevel@tonic-gate 			if (ret_aip) { /* need addrinfo. keep it. */
961*0Sstevel@tonic-gate 				while (cur && cur->ai_next)
962*0Sstevel@tonic-gate 					cur = cur->ai_next;
963*0Sstevel@tonic-gate 			} else if (cur->ai_next) { /* need hostent */
964*0Sstevel@tonic-gate 				struct addrinfo *aip = cur->ai_next;
965*0Sstevel@tonic-gate 
966*0Sstevel@tonic-gate 				for (aip = cur->ai_next; aip;
967*0Sstevel@tonic-gate 				     aip = aip->ai_next) {
968*0Sstevel@tonic-gate 					int m;
969*0Sstevel@tonic-gate 
970*0Sstevel@tonic-gate 					m = add_hostent(pvt, bp, hap, aip);
971*0Sstevel@tonic-gate 					if (m < 0) {
972*0Sstevel@tonic-gate 						had_error++;
973*0Sstevel@tonic-gate 						break;
974*0Sstevel@tonic-gate 					}
975*0Sstevel@tonic-gate 					if (m == 0)
976*0Sstevel@tonic-gate 						continue;
977*0Sstevel@tonic-gate 					if (hap < &pvt->h_addr_ptrs[MAXADDRS-1])
978*0Sstevel@tonic-gate 						hap++;
979*0Sstevel@tonic-gate 					*hap = NULL;
980*0Sstevel@tonic-gate 					bp += m;
981*0Sstevel@tonic-gate 				}
982*0Sstevel@tonic-gate 
983*0Sstevel@tonic-gate 				freeaddrinfo(cur->ai_next);
984*0Sstevel@tonic-gate 				cur->ai_next = NULL;
985*0Sstevel@tonic-gate 			}
986*0Sstevel@tonic-gate 			cp += n;
987*0Sstevel@tonic-gate 			break;
988*0Sstevel@tonic-gate 		default:
989*0Sstevel@tonic-gate 			abort();
990*0Sstevel@tonic-gate 		}
991*0Sstevel@tonic-gate 		if (!had_error)
992*0Sstevel@tonic-gate 			haveanswer++;
993*0Sstevel@tonic-gate 	}
994*0Sstevel@tonic-gate 	if (haveanswer) {
995*0Sstevel@tonic-gate 		if (ret_aip == NULL) {
996*0Sstevel@tonic-gate 			*ap = NULL;
997*0Sstevel@tonic-gate 			*hap = NULL;
998*0Sstevel@tonic-gate 
999*0Sstevel@tonic-gate 			if (pvt->res->nsort && haveanswer > 1 && qtype == T_A)
1000*0Sstevel@tonic-gate 				addrsort(pvt->res, pvt->h_addr_ptrs,
1001*0Sstevel@tonic-gate 					 haveanswer);
1002*0Sstevel@tonic-gate 			if (pvt->host.h_name == NULL) {
1003*0Sstevel@tonic-gate 				n = strlen(qname) + 1;	/* for the \0 */
1004*0Sstevel@tonic-gate 				if (n > (ep - bp) || n >= MAXHOSTNAMELEN)
1005*0Sstevel@tonic-gate 					goto no_recovery;
1006*0Sstevel@tonic-gate #ifdef HAVE_STRLCPY
1007*0Sstevel@tonic-gate 				strlcpy(bp, qname, ep - bp);
1008*0Sstevel@tonic-gate #else
1009*0Sstevel@tonic-gate 				strcpy(bp, qname);
1010*0Sstevel@tonic-gate #endif
1011*0Sstevel@tonic-gate 				pvt->host.h_name = bp;
1012*0Sstevel@tonic-gate 				bp += n;
1013*0Sstevel@tonic-gate 			}
1014*0Sstevel@tonic-gate 			if (pvt->res->options & RES_USE_INET6)
1015*0Sstevel@tonic-gate 				map_v4v6_hostent(&pvt->host, &bp, ep);
1016*0Sstevel@tonic-gate 			RES_SET_H_ERRNO(pvt->res, NETDB_SUCCESS);
1017*0Sstevel@tonic-gate 			return (&pvt->host);
1018*0Sstevel@tonic-gate 		} else {
1019*0Sstevel@tonic-gate 			if ((pai->ai_flags & AI_CANONNAME) != 0) {
1020*0Sstevel@tonic-gate 				if (pvt->host.h_name == NULL) {
1021*0Sstevel@tonic-gate 					sentinel.ai_next->ai_canonname =
1022*0Sstevel@tonic-gate 						strdup(qname);
1023*0Sstevel@tonic-gate 				}
1024*0Sstevel@tonic-gate 				else {
1025*0Sstevel@tonic-gate 					sentinel.ai_next->ai_canonname =
1026*0Sstevel@tonic-gate 						strdup(pvt->host.h_name);
1027*0Sstevel@tonic-gate 				}
1028*0Sstevel@tonic-gate 			}
1029*0Sstevel@tonic-gate 			*ret_aip = sentinel.ai_next;
1030*0Sstevel@tonic-gate 			return(NULL);
1031*0Sstevel@tonic-gate 		}
1032*0Sstevel@tonic-gate 	}
1033*0Sstevel@tonic-gate  no_recovery:
1034*0Sstevel@tonic-gate 	if (sentinel.ai_next) {
1035*0Sstevel@tonic-gate 		/* this should be impossible, but check it for safety */
1036*0Sstevel@tonic-gate 		freeaddrinfo(sentinel.ai_next);
1037*0Sstevel@tonic-gate 	}
1038*0Sstevel@tonic-gate 	if (error == NETDB_SUCCESS)
1039*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
1040*0Sstevel@tonic-gate 	else
1041*0Sstevel@tonic-gate 		RES_SET_H_ERRNO(pvt->res, error);
1042*0Sstevel@tonic-gate 	return(NULL);
1043*0Sstevel@tonic-gate }
1044*0Sstevel@tonic-gate 
1045*0Sstevel@tonic-gate static int
1046*0Sstevel@tonic-gate add_hostent(struct pvt *pvt, char *bp, char **hap, struct addrinfo *ai)
1047*0Sstevel@tonic-gate {
1048*0Sstevel@tonic-gate 	int addrlen;
1049*0Sstevel@tonic-gate 	char *addrp;
1050*0Sstevel@tonic-gate 	const char **tap;
1051*0Sstevel@tonic-gate 	char *obp = bp;
1052*0Sstevel@tonic-gate 
1053*0Sstevel@tonic-gate 	switch(ai->ai_addr->sa_family) {
1054*0Sstevel@tonic-gate 	case AF_INET6:
1055*0Sstevel@tonic-gate 		addrlen = IN6ADDRSZ;
1056*0Sstevel@tonic-gate 		addrp = (char *)&((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr;
1057*0Sstevel@tonic-gate 		break;
1058*0Sstevel@tonic-gate 	case AF_INET:
1059*0Sstevel@tonic-gate 		addrlen = INADDRSZ;
1060*0Sstevel@tonic-gate 		addrp = (char *)&((struct sockaddr_in *)ai->ai_addr)->sin_addr;
1061*0Sstevel@tonic-gate 		break;
1062*0Sstevel@tonic-gate 	default:
1063*0Sstevel@tonic-gate 		return(-1);	/* abort? */
1064*0Sstevel@tonic-gate 	}
1065*0Sstevel@tonic-gate 
1066*0Sstevel@tonic-gate 	/* Ensure alignment. */
1067*0Sstevel@tonic-gate 	bp = (char *)(((u_long)bp + (sizeof(align) - 1)) &
1068*0Sstevel@tonic-gate 		      ~(sizeof(align) - 1));
1069*0Sstevel@tonic-gate 	/* Avoid overflows. */
1070*0Sstevel@tonic-gate 	if (bp + addrlen >= &pvt->hostbuf[sizeof pvt->hostbuf])
1071*0Sstevel@tonic-gate 		return(-1);
1072*0Sstevel@tonic-gate 	if (hap >= &pvt->h_addr_ptrs[MAXADDRS-1])
1073*0Sstevel@tonic-gate 		return(0); /* fail, but not treat it as an error. */
1074*0Sstevel@tonic-gate 
1075*0Sstevel@tonic-gate 	/* Suppress duplicates. */
1076*0Sstevel@tonic-gate 	for (tap = (const char **)pvt->h_addr_ptrs;
1077*0Sstevel@tonic-gate 	     *tap != NULL;
1078*0Sstevel@tonic-gate 	     tap++)
1079*0Sstevel@tonic-gate 		if (memcmp(*tap, addrp, addrlen) == 0)
1080*0Sstevel@tonic-gate 			break;
1081*0Sstevel@tonic-gate 	if (*tap != NULL)
1082*0Sstevel@tonic-gate 		return (0);
1083*0Sstevel@tonic-gate 
1084*0Sstevel@tonic-gate 	memcpy(*hap = bp, addrp, addrlen);
1085*0Sstevel@tonic-gate 	return((bp + addrlen) - obp);
1086*0Sstevel@tonic-gate }
1087*0Sstevel@tonic-gate 
1088*0Sstevel@tonic-gate static void
1089*0Sstevel@tonic-gate map_v4v6_hostent(struct hostent *hp, char **bpp, char *ep) {
1090*0Sstevel@tonic-gate 	char **ap;
1091*0Sstevel@tonic-gate 
1092*0Sstevel@tonic-gate 	if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ)
1093*0Sstevel@tonic-gate 		return;
1094*0Sstevel@tonic-gate 	hp->h_addrtype = AF_INET6;
1095*0Sstevel@tonic-gate 	hp->h_length = IN6ADDRSZ;
1096*0Sstevel@tonic-gate 	for (ap = hp->h_addr_list; *ap; ap++) {
1097*0Sstevel@tonic-gate 		int i = (u_long)*bpp % sizeof(align);
1098*0Sstevel@tonic-gate 
1099*0Sstevel@tonic-gate 		if (i != 0)
1100*0Sstevel@tonic-gate 			i = sizeof(align) - i;
1101*0Sstevel@tonic-gate 
1102*0Sstevel@tonic-gate 		if ((ep - *bpp) < (i + IN6ADDRSZ)) {
1103*0Sstevel@tonic-gate 			/* Out of memory.  Truncate address list here. */
1104*0Sstevel@tonic-gate 			*ap = NULL;
1105*0Sstevel@tonic-gate 			return;
1106*0Sstevel@tonic-gate 		}
1107*0Sstevel@tonic-gate 		*bpp += i;
1108*0Sstevel@tonic-gate 		map_v4v6_address(*ap, *bpp);
1109*0Sstevel@tonic-gate 		*ap = *bpp;
1110*0Sstevel@tonic-gate 		*bpp += IN6ADDRSZ;
1111*0Sstevel@tonic-gate 	}
1112*0Sstevel@tonic-gate }
1113*0Sstevel@tonic-gate 
1114*0Sstevel@tonic-gate static void
1115*0Sstevel@tonic-gate addrsort(res_state statp, char **ap, int num) {
1116*0Sstevel@tonic-gate 	int i, j, needsort = 0, aval[MAXADDRS];
1117*0Sstevel@tonic-gate 	char **p;
1118*0Sstevel@tonic-gate 
1119*0Sstevel@tonic-gate 	p = ap;
1120*0Sstevel@tonic-gate 	for (i = 0; i < num; i++, p++) {
1121*0Sstevel@tonic-gate 		for (j = 0 ; (unsigned)j < statp->nsort; j++)
1122*0Sstevel@tonic-gate 			if (statp->sort_list[j].addr.s_addr ==
1123*0Sstevel@tonic-gate 			    (((struct in_addr *)(*p))->s_addr &
1124*0Sstevel@tonic-gate 			     statp->sort_list[j].mask))
1125*0Sstevel@tonic-gate 				break;
1126*0Sstevel@tonic-gate 		aval[i] = j;
1127*0Sstevel@tonic-gate 		if (needsort == 0 && i > 0 && j < aval[i-1])
1128*0Sstevel@tonic-gate 			needsort = i;
1129*0Sstevel@tonic-gate 	}
1130*0Sstevel@tonic-gate 	if (!needsort)
1131*0Sstevel@tonic-gate 		return;
1132*0Sstevel@tonic-gate 
1133*0Sstevel@tonic-gate 	while (needsort < num) {
1134*0Sstevel@tonic-gate 		for (j = needsort - 1; j >= 0; j--) {
1135*0Sstevel@tonic-gate 			if (aval[j] > aval[j+1]) {
1136*0Sstevel@tonic-gate 				char *hp;
1137*0Sstevel@tonic-gate 
1138*0Sstevel@tonic-gate 				i = aval[j];
1139*0Sstevel@tonic-gate 				aval[j] = aval[j+1];
1140*0Sstevel@tonic-gate 				aval[j+1] = i;
1141*0Sstevel@tonic-gate 
1142*0Sstevel@tonic-gate 				hp = ap[j];
1143*0Sstevel@tonic-gate 				ap[j] = ap[j+1];
1144*0Sstevel@tonic-gate 				ap[j+1] = hp;
1145*0Sstevel@tonic-gate 
1146*0Sstevel@tonic-gate 			} else
1147*0Sstevel@tonic-gate 				break;
1148*0Sstevel@tonic-gate 		}
1149*0Sstevel@tonic-gate 		needsort++;
1150*0Sstevel@tonic-gate 	}
1151*0Sstevel@tonic-gate }
1152*0Sstevel@tonic-gate 
1153*0Sstevel@tonic-gate static int
1154*0Sstevel@tonic-gate init(struct irs_ho *this) {
1155*0Sstevel@tonic-gate 	struct pvt *pvt = (struct pvt *)this->private;
1156*0Sstevel@tonic-gate 
1157*0Sstevel@tonic-gate 	if (!pvt->res && !ho_res_get(this))
1158*0Sstevel@tonic-gate 		return (-1);
1159*0Sstevel@tonic-gate 	if (((pvt->res->options & RES_INIT) == 0) &&
1160*0Sstevel@tonic-gate 	    res_ninit(pvt->res) == -1)
1161*0Sstevel@tonic-gate 		return (-1);
1162*0Sstevel@tonic-gate 	return (0);
1163*0Sstevel@tonic-gate }
1164