libresolv - zygaena/hammerhead

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#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#
#
# Copyright 2015 Gary Mills
# Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
# Use is subject to license terms.
#
# Copyright (c) 2018, Joyent, Inc.

LIBRARY= libresolv.a
VERS= .1

PICS=   pics/res_comp.o pics/res_debug.o pics/res_init.o \
	pics/res_mkquery.o pics/res_query.o pics/res_send.o \
	pics/res_gethost.o pics/res_sethost.o

pics/%.o: %.c
	$(COMPILE.c) -o $@ $<
	$(POST_PROCESS_O)

OBJECTS= \
res_gethost.o   res_comp.o      res_debug.o     res_init.o    res_mkquery.o  \
res_query.o     res_send.o      res_sethost.o

# include library definitions
include ../Makefile.lib

# install this library in the root filesystem
include ../Makefile.rootfs

SRCDIR =	.

CSTD=	$(CSTD_GNU89)

# Hammerhead: Force 64-bit build (flat-structure library defaults to 32-bit)
# Override i386_CFLAGS to use -m64 instead of the default -m32
i386_CFLAGS = -m64

# We really want to say this:
#	CPPFLAGS += -DDEBUG -DSYSV -D_REENTRANT -I. -I../common/inc
# but some system header files are replaced by local versions
# so we must put -I. ahead of the default include directories:
CPPFLAGS = -I. -I../common/inc $(CPPFLAGS.master) -DDEBUG -DSYSV -D_REENTRANT
LDLIBS += -lsocket -lnsl -lc
CFLAGS += $(CCVERBOSE)

CERRWARN += -Wno-parentheses
CERRWARN += $(CNOWARN_UNINIT)

# not linted
SMATCH=off

# Hammerhead: Use 64-bit library directory
ROOTDYNLIBS=	$(DYNLIB:%=$(ROOTLIBDIR64)/%)

# Hammerhead: removed stale COMPATLINKS override (was usr/lib/amd64/).
# Makefile.rootfs sets correct COMPATLINKS for flattened layout.

.KEEP_STATE:

LIBS = $(DYNLIB)

all: $(LIBS)

install: all $(ROOTDYNLIBS) $(ROOTCOMPATLINKS)


# include library targets
include ../Makefile.targ
 * Copyright (c) 1985, 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that this notice is preserved and that due credit is given
 * to the University of California at Berkeley. The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission. This software
 * is provided ``as is'' without express or implied warranty.
PORTIONS OF LIBRESOLV FUNCTIONALITY
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1994 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * Portions of this source code were derived from Berkeley 4.3 BSD
 * under license from the Regents of the University of California.
 */

#ifndef _ARPA_NAMESER_H
#define	_ARPA_NAMESER_H

#include <sys/isa_defs.h>

#ifdef	__cplusplus
extern "C" {
#endif

/*
 * Define constants based on rfc883
 */
#define	PACKETSZ	512		/* maximum packet size */
#define	MAXDNAME	256		/* maximum domain name */
#define	MAXCDNAME	255		/* maximum compressed domain name */
#define	MAXLABEL	63		/* maximum length of domain label */
	/* Number of bytes of fixed size data in query structure */
#define	QFIXEDSZ	4
	/* number of bytes of fixed size data in resource record */
#define	RRFIXEDSZ	10

/*
 * Internet nameserver port number
 */
#define	NAMESERVER_PORT	53

/*
 * Currently defined opcodes
 */
#define	QUERY		0x0		/* standard query */
#define	IQUERY		0x1		/* inverse query */
#define	STATUS		0x2		/* nameserver status query */
/* #define	xxx		0x3 */	/* 0x3 reserved */
	/* non standard */
#define	UPDATEA		0x9		/* add resource record */
#define	UPDATED		0xa		/* delete a specific resource record */
#define	UPDATEDA	0xb		/* delete all nemed resource record */
#define	UPDATEM		0xc		/* modify a specific resource record */
#define	UPDATEMA	0xd		/* modify all named resource record */

#define	ZONEINIT	0xe		/* initial zone transfer */
#define	ZONEREF		0xf		/* incremental zone referesh */

/*
 * Currently defined response codes
 */
#define	NOERROR		0		/* no error */
#define	FORMERR		1		/* format error */
#define	SERVFAIL	2		/* server failure */
#define	NXDOMAIN	3		/* non existent domain */
#define	NOTIMP		4		/* not implemented */
#define	REFUSED		5		/* query refused */
	/* non standard */
#define	NOCHANGE	0xf		/* update failed to change db */

/*
 * Type values for resources and queries
 */
#define	T_A		1		/* host address */
#define	T_NS		2		/* authoritative server */
#define	T_MD		3		/* mail destination */
#define	T_MF		4		/* mail forwarder */
#define	T_CNAME		5		/* connonical name */
#define	T_SOA		6		/* start of authority zone */
#define	T_MB		7		/* mailbox domain name */
#define	T_MG		8		/* mail group member */
#define	T_MR		9		/* mail rename name */
#define	T_NULL		10		/* null resource record */
#define	T_WKS		11		/* well known service */
#define	T_PTR		12		/* domain name pointer */
#define	T_HINFO		13		/* host information */
#define	T_MINFO		14		/* mailbox information */
#define	T_MX		15		/* mail routing information */
#define	T_TXT		16		/* text strings */
	/* non standard */
#define	T_UINFO		100		/* user (finger) information */
#define	T_UID		101		/* user ID */
#define	T_GID		102		/* group ID */
#define	T_UNSPEC	103		/* Unspecified format (binary data) */
	/* Query type values which do not appear in resource records */
#define	T_AXFR		252		/* transfer zone of authority */
#define	T_MAILB		253		/* transfer mailbox records */
#define	T_MAILA		254		/* transfer mail agent records */
#define	T_ANY		255		/* wildcard match */

/*
 * Values for class field
 */

#define	C_IN		1		/* the arpa internet */
#define	C_CHAOS		3		/* for chaos net at MIT */
#define	C_HS		4		/* for Hesiod name server at MIT */
	/* Query class values which do not appear in resource records */
#define	C_ANY		255		/* wildcard match */

/*
 * Status return codes for T_UNSPEC conversion routines
 */
#define	CONV_SUCCESS 0
#define	CONV_OVERFLOW -1
#define	CONV_BADFMT -2
#define	CONV_BADCKSUM -3
#define	CONV_BADBUFLEN -4

/*
 * Structure for query header, the order of the fields is machine and
 * compiler dependent, in our case, the bits within a byte are assignd
 * least significant first, while the order of transmition is most
 * significant first.  This requires a somewhat confusing rearrangement.
 */

typedef struct {
	u_short	id;		/* query identification number */
#if defined(_BIT_FIELDS_HTOL) || defined(BIT_ZERO_ON_LEFT)
	/* Bit zero on left:  SPARC and similar architectures */
			/* fields in third byte */
	u_char	qr:1;		/* response flag */
	u_char	opcode:4;	/* purpose of message */
	u_char	aa:1;		/* authoritive answer */
	u_char	tc:1;		/* truncated message */
	u_char	rd:1;		/* recursion desired */
			/* fields in fourth byte */
	u_char	ra:1;		/* recursion available */
	u_char	pr:1;		/* primary server required (non standard) */
	u_char	unused:2;	/* unused bits */
	u_char	rcode:4;	/* response code */
#else
#if defined(_BIT_FIELDS_LTOH) || defined(BIT_ZERO_ON_RIGHT)
	/* Bit zero on right:  Intel x86 and similar architectures */
			/* fields in third byte */
	u_char	rd:1;		/* recursion desired */
	u_char	tc:1;		/* truncated message */
	u_char	aa:1;		/* authoritive answer */
	u_char	opcode:4;	/* purpose of message */
	u_char	qr:1;		/* response flag */
			/* fields in fourth byte */
	u_char	rcode:4;	/* response code */
	u_char	unused:2;	/* unused bits */
	u_char	pr:1;		/* primary server required (non standard) */
	u_char	ra:1;		/* recursion available */
#else
	/* you must determine what the correct bit order is for your compiler */
	UNDEFINED_BIT_ORDER;
#endif
#endif
			/* remaining bytes */
	u_short	qdcount;	/* number of question entries */
	u_short	ancount;	/* number of answer entries */
	u_short	nscount;	/* number of authority entries */
	u_short	arcount;	/* number of resource entries */
} HEADER;

/*
 * Defines for handling compressed domain names
 */
#define	INDIR_MASK	0xc0

/*
 * Structure for passing resource records around.
 */
struct rrec {
	short	r_zone;			/* zone number */
	short	r_class;		/* class number */
	short	r_type;			/* type number */
	u_long	r_ttl;			/* time to live */
	int	r_size;			/* size of data area */
	char	*r_data;		/* pointer to data */
};

extern	u_short	_getshort();
extern	u_long	_getlong();

/*
 * Inline versions of get/put short/long.
 * Pointer is advanced; we assume that both arguments
 * are lvalues and will already be in registers.
 * cp MUST be u_char *.
 */
#define	GETSHORT(s, cp) { \
	(s) = *(cp)++ << 8; \
	(s) |= *(cp)++; \
}

#define	GETLONG(l, cp) { \
	(l) = *(cp)++ << 8; \
	(l) |= *(cp)++; (l) <<= 8; \
	(l) |= *(cp)++; (l) <<= 8; \
	(l) |= *(cp)++; \
}


#define	PUTSHORT(s, cp) { \
	*(cp)++ = (s) >> 8; \
	*(cp)++ = (s); \
}

/*
 * Warning: PUTLONG destroys its first argument.
 */
#define	PUTLONG(l, cp) { \
	(cp)[3] = l; \
	(cp)[2] = (l >>= 8); \
	(cp)[1] = (l >>= 8); \
	(cp)[0] = l >> 8; \
	(cp) += sizeof (u_long); \
}

#ifdef	__cplusplus
}
#endif

#endif /* _ARPA_NAMESER_H */
/*
 * This file and its contents are supplied under the terms of the
 * Common Development and Distribution License ("CDDL"), version 1.0.
 * You may only use this file in accordance with the terms of version
 * 1.0 of the CDDL.
 *
 * A full copy of the text of the CDDL should have accompanied this
 * source.  A copy of the CDDL is also available via the Internet at
 * http://www.illumos.org/license/CDDL.
 */

/*
 * Copyright 2015 Gary Mills
 */

#ifndef _CROSSL_H
#define	_CROSSL_H

/*
 * Definitions needed for cross-linkages between source files
 */

#ifdef __cplusplus
extern "C" {
#endif

extern int dn_comp(u_char *, u_char *, int, u_char **, u_char **);
extern int dn_expand(u_char *, u_char *, u_char *, u_char *, int);
extern int dn_skipname(u_char *, u_char *);

extern int res_init(void);
extern int res_mkquery(int, char *, int, int, char *, int, struct rrec *,
    char *, int);
extern int res_query(char *, int, int, u_char *, int);
extern int res_querydomain(char *, char *, int, int, u_char *, int);
extern int res_search(char *, int, int, u_char *, int);
extern int res_send(char *, int, char *, int);

extern void putlong(u_long, u_char *);
extern void putshort(u_short, u_char *);
extern void p_query(char *);
extern void _res_close();


#ifdef __cplusplus
}
#endif

#endif /* _CROSSL_H */
#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#
#
# Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
#

#
# MAPFILE HEADER START
#
# WARNING:  STOP NOW.  DO NOT MODIFY THIS FILE.
# Object versioning must comply with the rules detailed in
#
#	usr/src/lib/README.mapfiles
#
# You should not be making modifications here until you've read the most current
# copy of that file. If you need help, contact a gatekeeper for guidance.
#
# MAPFILE HEADER END
#

$mapfile_version 2

# Due to mistakes made early in the history of this library, there are
# no SUNW_1.1 symbols, but the version is now kept as a placeholder.
# Don't add any symbols to this version.

SYMBOL_VERSION SUNW_1.1 {
    global:
	SUNW_1.1;
} SUNW_0.7;

SYMBOL_VERSION SUNW_0.7 {
    global:
	dn_comp;
	dn_expand;
	dn_skipname;
	fp_query;
	_getlong;
	_getshort;
	h_errno		{ FLAGS = NODIRECT; FILTER = libnsl.so.1; };
	hostalias;
	p_cdname;
	p_class;
	p_query;
	p_rr;
	p_time;
	p_type;
	putlong;
	_res		{
			  ASSERT = {
				  TYPE = OBJECT;
				  SIZE = addrsize[99];
				};
			};
	res_init;
	res_mkquery;
	res_query;
	res_querydomain;
	res_search;
	res_send;
	strcasecmp	{ TYPE = FUNCTION; FILTER = libc.so.1; };
	strncasecmp	{ TYPE = FUNCTION; FILTER = libc.so.1; };
};

SYMBOL_VERSION SUNWprivate_1.1 {
    global:
	res_endhostent;
	res_gethostbyaddr;
	res_gethostbyname;
	_res_opcodes		{
				  ASSERT = {
					  TYPE = OBJECT;
					  SIZE = addrsize[16];
					};
				};
	_res_resultcodes	{
				  ASSERT = {
					  TYPE = OBJECT;
					  SIZE = addrsize[16];
					};
				};
	res_sethostent;
	__res_set_no_hosts_fallback;
    local:
	*;
};
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1996 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * Portions of this source code were derived from Berkeley 4.3 BSD
 * under license from the Regents of the University of California.
 */

/*
 * Structures returned by network data base library.
 * All addresses are supplied in host order, and
 * returned in network order (suitable for use in system calls).
 */

#ifndef _NETDB_H
#define	_NETDB_H

#ifdef	__cplusplus
extern "C" {
#endif

#define	_PATH_HEQUIV	"/etc/hosts.equiv"
#define	_PATH_HOSTS	"/etc/hosts"
#define	_PATH_NETWORKS	"/etc/networks"
#define	_PATH_PROTOCOLS	"/etc/protocols"
#define	_PATH_SERVICES	"/etc/services"

struct	hostent {
	char	*h_name;	/* official name of host */
	char	**h_aliases;	/* alias list */
	int	h_addrtype;	/* host address type */
	int	h_length;	/* length of address */
	char	**h_addr_list;	/* list of addresses from name server */
#define	h_addr	h_addr_list[0]	/* address, for backward compatiblity */
};

/*
 * Assumption here is that a network number
 * fits in 32 bits -- probably a poor one.
 */
struct	netent {
	char		*n_name;	/* official name of net */
	char		**n_aliases;	/* alias list */
	int		n_addrtype;	/* net address type */
	unsigned long	n_net;		/* network # */
};

struct	servent {
	char	*s_name;	/* official service name */
	char	**s_aliases;	/* alias list */
	int	s_port;		/* port # */
	char	*s_proto;	/* protocol to use */
};

struct	protoent {
	char	*p_name;	/* official protocol name */
	char	**p_aliases;	/* alias list */
	int	p_proto;	/* protocol # */
};

#ifdef	__STDC__
struct hostent	*gethostbyname_r
	(const char *,		 struct hostent *, char *, int, int *h_errnop);
struct hostent	*gethostbyaddr_r
	(const char *, int, int, struct hostent *, char *, int, int *h_errnop);
struct hostent	*gethostent_r(struct hostent *, char *, int, int *h_errnop);

struct servent	*getservbyname_r
	(const char *name, const char *, struct servent *, char *, int);
struct servent	*getservbyport_r
	(int port,	   const char *, struct servent *, char *, int);
struct servent	*getservent_r(struct	servent *, char *, int);

struct netent	*getnetbyname_r
	(const char *, struct netent *, char *, int);
struct netent	*getnetbyaddr_r(long, int, struct netent *, char *, int);
struct netent	*getnetent_r(struct netent *, char *, int);

struct protoent	*getprotobyname_r
	(const char *, struct protoent *, char *, int);
struct protoent	*getprotobynumber_r
	(int, struct protoent *, char *, int);
struct protoent	*getprotoent_r(struct protoent *, char *, int);

int getnetgrent_r(char **, char **, char **, char *, int);
int innetgr(const char *, const char *, const char *, const char *);

/* Old interfaces that return a pointer to a static area;  MT-unsafe */
struct hostent	*gethostbyname(const char *);
struct hostent	*gethostbyaddr(const char *, int, int);
struct hostent	*gethostent(void);
struct netent	*getnetbyname(const char *);
struct netent	*getnetbyaddr(long, int);
struct netent	*getnetent(void);
struct servent	*getservbyname(const char *, const char *);
struct servent	*getservbyport(int, const char *);
struct servent	*getservent(void);
struct protoent	*getprotobyname(const char *);
struct protoent	*getprotobynumber(int);
struct protoent	*getprotoent(void);
int		 getnetgrent(char **, char **, char **);

int sethostent(int);
int endhostent(void);
int setnetent(int);
int endnetent(void);
int setservent(int);
int endservent(void);
int setprotoent(int);
int endprotoent(void);
int setnetgrent(const char *);
int endnetgrent(void);
int rcmd(char **ahost, unsigned short inport,
	const char *luser, const char *ruser, const char *cmd, int *fd2p);
int rexec(char **ahost, unsigned short inport,
	const char *user, const char *passwd, const char *cmd, int *fd2p);
int rresvport(int *);
int ruserok(const char *rhost, int suser, const char *ruser, const char *luser);
#else
struct hostent	*gethostbyname_r();
struct hostent	*gethostbyaddr_r();
struct hostent	*gethostent_r();
struct servent	*getservbyname_r();
struct servent	*getservbyport_r();
struct servent	*getservent_r();
struct netent	*getnetbyname_r();
struct netent	*getnetbyaddr_r();
struct netent	*getnetent_r();
struct protoent	*getprotobyname_r();
struct protoent	*getprotobynumber_r();
struct protoent	*getprotoent_r();
int		 getnetgrent_r();
int		 innetgr();

/* Old interfaces that return a pointer to a static area;  MT-unsafe */
struct hostent	*gethostbyname();
struct hostent	*gethostbyaddr();
struct hostent	*gethostent();
struct netent	*getnetbyname();
struct netent	*getnetbyaddr();
struct netent	*getnetent();
struct servent	*getservbyname();
struct servent	*getservbyport();
struct servent	*getservent();
struct protoent	*getprotobyname();
struct protoent	*getprotobynumber();
struct protoent	*getprotoent();
int		 getnetgrent();

int sethostent();
int endhostent();
int setnetent();
int endnetent();
int setservent();
int endservent();
int setprotoent();
int endprotoent();
int setnetgrent();
int endnetgrent();
int rcmd();
int rexec();
int rresvport();
int ruserok();
#endif

/*
 * Error return codes from gethostbyname() and gethostbyaddr()
 * (when using the resolver)
 */

extern  int h_errno;

#define	HOST_NOT_FOUND	1 /* Authoritive Answer Host not found */
#define	TRY_AGAIN	2 /* Non-Authoritive Host not found, or SERVERFAIL */
#define	NO_RECOVERY	3 /* Non recoverable errors, FORMERR, REFUSED, NOTIMP */
#define	NO_DATA		4 /* Valid name, no data record of requested type */
#define	NO_ADDRESS	NO_DATA		/* no address, look for MX record */

#define	MAXHOSTNAMELEN	256

#define	MAXALIASES	35
#define	MAXADDRS	35

#ifdef	__cplusplus
}
#endif

#endif	/* _NETDB_H */
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <sys/types.h>
#include <stdio.h>
#include <arpa/nameser.h>

static int dn_find(u_char *exp_dn, u_char *msg, u_char **dnptrs,
	u_char **lastdnptr);


/*
 * Expand compressed domain name 'comp_dn' to full domain name.
 * 'msg' is a pointer to the begining of the message,
 * 'eomorig' points to the first location after the message,
 * 'exp_dn' is a pointer to a buffer of size 'length' for the result.
 * Return size of compressed name or -1 if there was an error.
 */
int
dn_expand(msg, eomorig, comp_dn, exp_dn, length)
	u_char *msg, *eomorig, *comp_dn, *exp_dn;
	int length;
{
	register u_char *cp, *dn;
	register int n, c;
	u_char *eom;
	int len = -1, checked = 0;

	dn = exp_dn;
	cp = comp_dn;
	eom = exp_dn + length;
	/*
	 * fetch next label in domain name
	 */
	while (n = *cp++) {
		/*
		 * Check for indirection
		 */
		switch (n & INDIR_MASK) {
		case 0:
			if (dn != exp_dn) {
				if (dn >= eom)
					return (-1);
				*dn++ = '.';
			}
			if (dn+n >= eom)
				return (-1);
			checked += n + 1;
			while (--n >= 0) {
				if ((c = *cp++) == '.') {
					if (dn + n + 2 >= eom)
						return (-1);
					*dn++ = '\\';
				}
				*dn++ = c;
				if (cp >= eomorig)	/* out of range */
					return (-1);
			}
			break;

		case INDIR_MASK:
			if (len < 0)
				len = cp - comp_dn + 1;
			cp = msg + (((n & 0x3f) << 8) | (*cp & 0xff));
			if (cp < msg || cp >= eomorig)	/* out of range */
				return (-1);
			checked += 2;
			/*
			 * Check for loops in the compressed name;
			 * if we've looked at the whole message,
			 * there must be a loop.
			 */
			if (checked >= eomorig - msg)
				return (-1);
			break;

		default:
			return (-1);			/* flag error */
		}
	}
	*dn = '\0';
	if (len < 0)
		len = cp - comp_dn;
	return (len);
}

/*
 * Compress domain name 'exp_dn' into 'comp_dn'.
 * Return the size of the compressed name or -1.
 * 'length' is the size of the array pointed to by 'comp_dn'.
 * 'dnptrs' is a list of pointers to previous compressed names. dnptrs[0]
 * is a pointer to the beginning of the message. The list ends with NULL.
 * 'lastdnptr' is a pointer to the end of the arrary pointed to
 * by 'dnptrs'. Side effect is to update the list of pointers for
 * labels inserted into the message as we compress the name.
 * If 'dnptr' is NULL, we don't try to compress names. If 'lastdnptr'
 * is NULL, we don't update the list.
 */
int
dn_comp(exp_dn, comp_dn, length, dnptrs, lastdnptr)
	u_char *exp_dn, *comp_dn;
	int length;
	u_char **dnptrs, **lastdnptr;
{
	register u_char *cp, *dn;
	register int c, l;
	u_char **cpp, **lpp, *sp, *eob;
	u_char *msg;

	dn = exp_dn;
	cp = comp_dn;
	eob = cp + length;
	if (dnptrs != NULL) {
		if ((msg = *dnptrs++) != NULL) {
			for (cpp = dnptrs; *cpp != NULL; cpp++)
				;
			lpp = cpp;	/* end of list to search */
		}
	} else
		msg = NULL;
	for (c = *dn++; c != '\0'; /*EMPTY*/) {
		/* look to see if we can use pointers */
		if (msg != NULL) {
			if ((l = dn_find(dn-1, msg, dnptrs, lpp)) >= 0) {
				if (cp+1 >= eob)
					return (-1);
				*cp++ = (l >> 8) | INDIR_MASK;
				*cp++ = l % 256;
				return (cp - comp_dn);
			}
			/* not found, save it */
			if (lastdnptr != NULL && cpp < lastdnptr-1) {
				*cpp++ = cp;
				*cpp = NULL;
			}
		}
		sp = cp++;	/* save ptr to length byte */
		do {
			if (c == '.') {
				c = *dn++;
				break;
			}
			if (c == '\\') {
				if ((c = *dn++) == '\0')
					break;
			}
			if (cp >= eob) {
				if (msg != NULL)
					*lpp = NULL;
				return (-1);
			}
			*cp++ = c;
		} while ((c = *dn++) != '\0');
		/* catch trailing '.'s but not '..' */
		if ((l = cp - sp - 1) == 0 && c == '\0') {
			cp--;
			break;
		}
		if (l <= 0 || l > MAXLABEL) {
			if (msg != NULL)
				*lpp = NULL;
			return (-1);
		}
		*sp = l;
	}
	if (cp >= eob) {
		if (msg != NULL)
			*lpp = NULL;
		return (-1);
	}
	*cp++ = '\0';
	return (cp - comp_dn);
}

/*
 * Skip over a compressed domain name. Return the size or -1.
 */
int
dn_skipname(comp_dn, eom)
	u_char *comp_dn, *eom;
{
	register u_char *cp;
	register int n;

	cp = comp_dn;
	while (cp < eom && (n = *cp++)) {
		/*
		 * check for indirection
		 */
		switch (n & INDIR_MASK) {
		case 0:		/* normal case, n == len */
			cp += n;
			continue;
		default:	/* illegal type */
			return (-1);
		case INDIR_MASK:	/* indirection */
			cp++;
		}
		break;
	}
	return (cp - comp_dn);
}

/*
 * Search for expanded name from a list of previously compressed names.
 * Return the offset from msg if found or -1.
 * dnptrs is the pointer to the first name on the list,
 * not the pointer to the start of the message.
 */
static int
dn_find(u_char *exp_dn, u_char *msg, u_char **dnptrs, u_char **lastdnptr)
{
	register u_char *dn, *cp, **cpp;
	register int n;
	u_char *sp;

	for (cpp = dnptrs; cpp < lastdnptr; cpp++) {
		dn = exp_dn;
		sp = cp = *cpp;
		while (n = *cp++) {
			/*
			 * check for indirection
			 */
			switch (n & INDIR_MASK) {
			case 0:		/* normal case, n == len */
				while (--n >= 0) {
					if (*dn == '.')
						goto next;
					if (*dn == '\\')
						dn++;
					if (*dn++ != *cp++)
						goto next;
				}
				if ((n = *dn++) == '\0' && *cp == '\0')
					return (sp - msg);
				if (n == '.')
					continue;
				goto next;

			default:	/* illegal type */
				return (-1);

			case INDIR_MASK:	/* indirection */
				cp = msg + (((n & 0x3f) << 8) | *cp);
			}
		}
		if (*dn == '\0')
			return (sp - msg);
	next:	/*EMPTY*/;
	}
	return (-1);
}

/*
 * Routines to insert/extract short/long's. Must account for byte
 * order and non-alignment problems. This code at least has the
 * advantage of being portable.
 *
 * used by sendmail.
 */

u_short
_getshort(msgp)
	u_char *msgp;
{
	register u_char *p = (u_char *) msgp;
#ifdef vax
	/*
	 * vax compiler doesn't put shorts in registers
	 */
	register u_long u;
#else
	register u_short u;
#endif

	u = *p++ << 8;
	return ((u_short)(u | *p));
}

u_long
_getlong(msgp)
	u_char *msgp;
{
	register u_char *p = (u_char *) msgp;
	register u_long u;

	u = *p++; u <<= 8;
	u |= *p++; u <<= 8;
	u |= *p++; u <<= 8;
	return (u | *p);
}

void
putshort(s, msgp)
	register u_short s;
	register u_char *msgp;
{

	msgp[1] = s;
	msgp[0] = s >> 8;
}

void
putlong(l, msgp)
	register u_long l;
	register u_char *msgp;
{

	msgp[3] = l;
	msgp[2] = (l >>= 8);
	msgp[1] = (l >>= 8);
	msgp[0] = l >> 8;
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Gary Mills
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <string.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include "crossl.h"

void fp_query(char *msg, FILE *file);

char *_res_opcodes[] = {
	"QUERY",
	"IQUERY",
	"CQUERYM",
	"CQUERYU",
	"4",
	"5",
	"6",
	"7",
	"8",
	"UPDATEA",
	"UPDATED",
	"UPDATEDA",
	"UPDATEM",
	"UPDATEMA",
	"ZONEINIT",
	"ZONEREF",
};

char *_res_resultcodes[] = {
	"NOERROR",
	"FORMERR",
	"SERVFAIL",
	"NXDOMAIN",
	"NOTIMP",
	"REFUSED",
	"6",
	"7",
	"8",
	"9",
	"10",
	"11",
	"12",
	"13",
	"14",
	"NOCHANGE",
};

void
p_query(msg)
	char *msg;
{
	fp_query(msg, stdout);
}

/*
 * Print the contents of a query.
 * This is intended to be primarily a debugging routine.
 */
void
fp_query(msg, file)
	char *msg;
	FILE *file;
{
	register char *cp;
	register HEADER *hp;
	register int n;

	/*
	 * Print header fields.
	 */
	hp = (HEADER *)msg;
	cp = msg + sizeof (HEADER);
	fprintf(file, "HEADER:\n");
	fprintf(file, "\topcode = %s", _res_opcodes[hp->opcode]);
	fprintf(file, ", id = %d", ntohs(hp->id));
	fprintf(file, ", rcode = %s\n", _res_resultcodes[hp->rcode]);
	fprintf(file, "\theader flags: ");
	if (hp->qr)
		fprintf(file, " qr");
	if (hp->aa)
		fprintf(file, " aa");
	if (hp->tc)
		fprintf(file, " tc");
	if (hp->rd)
		fprintf(file, " rd");
	if (hp->ra)
		fprintf(file, " ra");
	if (hp->pr)
		fprintf(file, " pr");
	fprintf(file, "\n\tqdcount = %d", ntohs(hp->qdcount));
	fprintf(file, ", ancount = %d", ntohs(hp->ancount));
	fprintf(file, ", nscount = %d", ntohs(hp->nscount));
	fprintf(file, ", arcount = %d\n\n", ntohs(hp->arcount));
	/*
	 * Print question records.
	 */
	if (n = ntohs(hp->qdcount)) {
		fprintf(file, "QUESTIONS:\n");
		while (--n >= 0) {
			fprintf(file, "\t");
			cp = p_cdname(cp, msg, file);
			if (cp == NULL)
				return;
			fprintf(file, ", type = %s", p_type(_getshort(cp)));
			cp += sizeof (u_short);
			fprintf(file, ", class = %s\n\n",
						p_class(_getshort(cp)));
			cp += sizeof (u_short);
		}
	}
	/*
	 * Print authoritative answer records
	 */
	if (n = ntohs(hp->ancount)) {
		fprintf(file, "ANSWERS:\n");
		while (--n >= 0) {
			fprintf(file, "\t");
			cp = p_rr(cp, msg, file);
			if (cp == NULL)
				return;
		}
	}
	/*
	 * print name server records
	 */
	if (n = ntohs(hp->nscount)) {
		fprintf(file, "NAME SERVERS:\n");
		while (--n >= 0) {
			fprintf(file, "\t");
			cp = p_rr(cp, msg, file);
			if (cp == NULL)
				return;
		}
	}
	/*
	 * print additional records
	 */
	if (n = ntohs(hp->arcount)) {
		fprintf(file, "ADDITIONAL RECORDS:\n");
		while (--n >= 0) {
			fprintf(file, "\t");
			cp = p_rr(cp, msg, file);
			if (cp == NULL)
				return;
		}
	}
}

char *
p_cdname(cp, msg, file)
	char *cp, *msg;
	FILE *file;
{
	char name[MAXDNAME];
	int n;

	if ((n = dn_expand((u_char *)msg, (u_char *)(msg + 512), (u_char *)cp,
	    (u_char *)name, sizeof (name))) < 0)
		return (NULL);
	if (name[0] == '\0') {
		name[0] = '.';
		name[1] = '\0';
	}
	fputs(name, file);
	return (cp + n);
}

/*
 * Print resource record fields in human readable form.
 */
char *
p_rr(cp, msg, file)
	char *cp, *msg;
	FILE *file;
{
	int type, class, dlen, n, c;
	struct in_addr inaddr;
	char *cp1, *cp2;

	if ((cp = p_cdname(cp, msg, file)) == NULL)
		return (NULL);			/* compression error */
	fprintf(file, "\n\ttype = %s", p_type(type = _getshort(cp)));
	cp += sizeof (u_short);
	fprintf(file, ", class = %s", p_class(class = _getshort(cp)));
	cp += sizeof (u_short);
	fprintf(file, ", ttl = %s", p_time(_getlong(cp)));
	cp += sizeof (u_long);
	fprintf(file, ", dlen = %d\n", dlen = _getshort(cp));
	cp += sizeof (u_short);
	cp1 = cp;
	/*
	 * Print type specific data, if appropriate
	 */
	switch (type) {
	case T_A:
		switch (class) {
		case C_IN:
		case C_HS:
#ifdef SYSV
			memcpy((void *)&inaddr, (void *)cp, sizeof (inaddr));
#else
			bcopy(cp, (char *)&inaddr, sizeof (inaddr));
#endif
			if (dlen == 4) {
				fprintf(file, "\tinternet address = %s\n",
					inet_ntoa(inaddr));
				cp += dlen;
			} else if (dlen == 7) {
				fprintf(file, "\tinternet address = %s",
					inet_ntoa(inaddr));
				fprintf(file, ", protocol = %d", cp[4]);
				fprintf(file, ", port = %d\n",
					(cp[5] << 8) + cp[6]);
				cp += dlen;
			}
			break;
		default:
			cp += dlen;
		}
		break;
	case T_CNAME:
	case T_MB:
	case T_MG:
	case T_MR:
	case T_NS:
	case T_PTR:
		fprintf(file, "\tdomain name = ");
		cp = p_cdname(cp, msg, file);
		fprintf(file, "\n");
		break;

	case T_HINFO:
		if (n = *cp++) {
			fprintf(file, "\tCPU=%.*s\n", n, cp);
			cp += n;
		}
		if (n = *cp++) {
			fprintf(file, "\tOS=%.*s\n", n, cp);
			cp += n;
		}
		break;

	case T_SOA:
		fprintf(file, "\torigin = ");
		cp = p_cdname(cp, msg, file);
		fprintf(file, "\n\tmail addr = ");
		cp = p_cdname(cp, msg, file);
		fprintf(file, "\n\tserial = %ld", _getlong(cp));
		cp += sizeof (u_long);
		fprintf(file, "\n\trefresh = %s", p_time(_getlong(cp)));
		cp += sizeof (u_long);
		fprintf(file, "\n\tretry = %s", p_time(_getlong(cp)));
		cp += sizeof (u_long);
		fprintf(file, "\n\texpire = %s", p_time(_getlong(cp)));
		cp += sizeof (u_long);
		fprintf(file, "\n\tmin = %s\n", p_time(_getlong(cp)));
		cp += sizeof (u_long);
		break;

	case T_MX:
		fprintf(file, "\tpreference = %ld,", _getshort(cp));
		cp += sizeof (u_short);
		fprintf(file, " name = ");
		cp = p_cdname(cp, msg, file);
		break;

	case T_TXT:
		(void) fputs("\t\"", file);
		cp2 = cp1 + dlen;
		while (cp < cp2) {
			if (n = (unsigned char) *cp++) {
				for (c = n; c > 0 && cp < cp2; c--)
					if (*cp == '\n') {
					    (void) putc('\\', file);
					    (void) putc(*cp++, file);
					} else
					    (void) putc(*cp++, file);
			}
		}
		(void) fputs("\"\n", file);
		break;

	case T_MINFO:
		fprintf(file, "\trequests = ");
		cp = p_cdname(cp, msg, file);
		fprintf(file, "\n\terrors = ");
		cp = p_cdname(cp, msg, file);
		break;

	case T_UINFO:
		fprintf(file, "\t%s\n", cp);
		cp += dlen;
		break;

	case T_UID:
	case T_GID:
		if (dlen == 4) {
			fprintf(file, "\t%ld\n", _getlong(cp));
			cp += sizeof (int);
		}
		break;

	case T_WKS:
		if (dlen < sizeof (u_long) + 1)
			break;
#ifdef SYSV
		memcpy((void *)&inaddr, (void *)cp, sizeof (inaddr));
#else
		bcopy(cp, (char *)&inaddr, sizeof (inaddr));
#endif
		cp += sizeof (u_long);
		fprintf(file, "\tinternet address = %s, protocol = %d\n\t",
			inet_ntoa(inaddr), *cp++);
		n = 0;
		while (cp < cp1 + dlen) {
			c = *cp++;
			do {
				if (c & 0200)
					fprintf(file, " %d", n);
				c <<= 1;
			} while (++n & 07);
		}
		putc('\n', file);
		break;

#ifdef ALLOW_T_UNSPEC
	case T_UNSPEC:
		{
			int NumBytes = 8;
			char *DataPtr;
			int i;

			if (dlen < NumBytes) NumBytes = dlen;
			fprintf(file, "\tFirst %d bytes of hex data:",
				NumBytes);
			for (i = 0, DataPtr = cp; i < NumBytes; i++, DataPtr++)
				fprintf(file, " %x", *DataPtr);
			fputs("\n", file);
			cp += dlen;
		}
		break;
#endif /* ALLOW_T_UNSPEC */

	default:
		fprintf(file, "\t???\n");
		cp += dlen;
	}
	if (cp != cp1 + dlen) {
		fprintf(file, "packet size error (%#x != %#x)\n", cp, cp1+dlen);
		cp = NULL;
	}
	fprintf(file, "\n");
	return (cp);
}

static	char nbuf[40];

/*
 * Return a string for the type
 */
char *
p_type(type)
	int type;
{
	switch (type) {
	case T_A:
		return ("A");
	case T_NS:		/* authoritative server */
		return ("NS");
	case T_CNAME:		/* canonical name */
		return ("CNAME");
	case T_SOA:		/* start of authority zone */
		return ("SOA");
	case T_MB:		/* mailbox domain name */
		return ("MB");
	case T_MG:		/* mail group member */
		return ("MG");
	case T_MR:		/* mail rename name */
		return ("MR");
	case T_NULL:		/* null resource record */
		return ("NULL");
	case T_WKS:		/* well known service */
		return ("WKS");
	case T_PTR:		/* domain name pointer */
		return ("PTR");
	case T_HINFO:		/* host information */
		return ("HINFO");
	case T_MINFO:		/* mailbox information */
		return ("MINFO");
	case T_MX:		/* mail routing info */
		return ("MX");
	case T_TXT:		/* text */
		return ("TXT");
	case T_AXFR:		/* zone transfer */
		return ("AXFR");
	case T_MAILB:		/* mail box */
		return ("MAILB");
	case T_MAILA:		/* mail address */
		return ("MAILA");
	case T_ANY:		/* matches any type */
		return ("ANY");
	case T_UINFO:
		return ("UINFO");
	case T_UID:
		return ("UID");
	case T_GID:
		return ("GID");
#ifdef ALLOW_T_UNSPEC
	case T_UNSPEC:
		return ("UNSPEC");
#endif /* ALLOW_T_UNSPEC */
	default:
		(void) sprintf(nbuf, "%d", type);
		return (nbuf);
	}
}

/*
 * Return a mnemonic for class
 */
char *
p_class(class)
	int class;
{

	switch (class) {
	case C_IN:		/* internet class */
		return ("IN");
	case C_HS:		/* hesiod class */
		return ("HS");
	case C_ANY:		/* matches any class */
		return ("ANY");
	default:
		(void) sprintf(nbuf, "%d", class);
		return (nbuf);
	}
}

/*
 * Return a mnemonic for a time to live
 */
char *
p_time(value)
	u_long value;
{
	int secs, mins, hours;
	register char *p;

	if (value == 0) {
		strcpy(nbuf, "0 secs");
		return (nbuf);
	}

	secs = value % 60;
	value /= 60;
	mins = value % 60;
	value /= 60;
	hours = value % 24;
	value /= 24;

#define	PLURALIZE(x)	x, (x == 1) ? "" : "s"
	p = nbuf;
	if (value) {
		(void) sprintf(p, "%d day%s", PLURALIZE(value));
		while (*++p);
	}
	if (hours) {
		if (value)
			*p++ = ' ';
		(void) sprintf(p, "%d hour%s", PLURALIZE(hours));
		while (*++p);
	}
	if (mins) {
		if (value || hours)
			*p++ = ' ';
		(void) sprintf(p, "%d min%s", PLURALIZE(mins));
		while (*++p);
	}
	if (secs || ! (value || hours || mins)) {
		if (value || hours || mins)
			*p++ = ' ';
		(void) sprintf(p, "%d sec%s", PLURALIZE(secs));
	}
	return (nbuf);
}
/*
 * Copyright 2015 Gary Mills
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 1985, 1988 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that this notice is preserved and that due credit is given
 * to the University of California at Berkeley. The name of the University
 * may not be used to endorse or promote products derived from this
 * software without specific prior written permission. This software
 * is provided ``as is'' without express or implied warranty.
 *
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <ctype.h>
#include <netdb.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <syslog.h>
#include "crossl.h"

/*
 * When the name service switch calls libresolv, it doesn't want fallback
 * to /etc/hosts, so we provide a method to turn it off.
 */
static int	no_hosts_fallback = 0;

void
__res_set_no_hosts_fallback(void) {
	no_hosts_fallback = 1;
}

static int
__res_no_hosts_fallback(void) {
	return(no_hosts_fallback);
}

static char *h_addr_ptrs[MAXADDRS + 1];

static struct hostent host;
static char *host_aliases[MAXALIASES];
static char hostbuf[BUFSIZ+1];
static struct in_addr host_addr;
static char HOSTDB[] = "/etc/hosts";
static FILE *hostf = NULL;
static char hostaddr[MAXADDRS];
static char *host_addrs[2];
static int stayopen = 0;
static char *any();

#if PACKETSZ > 1024
#define	MAXPACKET	PACKETSZ
#else
#define	MAXPACKET	1024
#endif

typedef union {
	HEADER hdr;
	u_char buf[MAXPACKET];
} querybuf;

static union {
	long al;
	char ac;
} align;


int h_errno;

static struct hostent *
getanswer(answer, anslen, iquery)
	querybuf *answer;
	int anslen;
	int iquery;
{
	register HEADER *hp;
	register u_char *cp;
	register int n;
	u_char *eom;
	char *bp, **ap;
	int type, class, buflen, ancount, qdcount;
	int haveanswer, getclass = C_ANY;
	char **hap;

	eom = answer->buf + anslen;
	/*
	 * find first satisfactory answer
	 */
	hp = &answer->hdr;
	ancount = ntohs(hp->ancount);
	qdcount = ntohs(hp->qdcount);
	bp = hostbuf;
	buflen = sizeof (hostbuf);
	cp = answer->buf + sizeof (HEADER);
	if (qdcount) {
		if (iquery) {
			if ((n = dn_expand(answer->buf, eom,
			    cp, (u_char *)bp, buflen)) < 0) {
				h_errno = NO_RECOVERY;
				return ((struct hostent *) NULL);
			}
			cp += n + QFIXEDSZ;
			host.h_name = bp;
			n = strlen(bp) + 1;
			bp += n;
			buflen -= n;
		} else
			cp += dn_skipname(cp, eom) + QFIXEDSZ;
		while (--qdcount > 0)
			cp += dn_skipname(cp, eom) + QFIXEDSZ;
	} else if (iquery) {
		if (hp->aa)
			h_errno = HOST_NOT_FOUND;
		else
			h_errno = TRY_AGAIN;
		return ((struct hostent *) NULL);
	}
	ap = host_aliases;
	host.h_aliases = host_aliases;
	hap = h_addr_ptrs;
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
	host.h_addr_list = h_addr_ptrs;
#endif
	haveanswer = 0;
	while (--ancount >= 0 && cp < eom && haveanswer < MAXADDRS) {
		if ((n = dn_expand(answer->buf, eom,
		    cp, (u_char *)bp, buflen)) < 0)
			break;
		cp += n;
		type = _getshort(cp);
		cp += sizeof (u_short);
		class = _getshort(cp);
		cp += sizeof (u_short) + sizeof (u_long);
		n = _getshort(cp);
		cp += sizeof (u_short);
		if (type == T_CNAME) {
			cp += n;
			if (ap >= &host_aliases[MAXALIASES-1])
				continue;
			*ap++ = bp;
			n = strlen(bp) + 1;
			bp += n;
			buflen -= n;
			continue;
		}
		if (iquery && type == T_PTR) {
			if ((n = dn_expand(answer->buf, eom,
			    cp, (u_char *)bp, buflen)) < 0) {
				cp += n;
				continue;
			}
			cp += n;
			host.h_name = bp;
			return (&host);
		}
		if (iquery || type != T_A) {
#ifdef DEBUG
			if (_res.options & RES_DEBUG)
				printf("unexpected answer type %d, size %d\n",
					type, n);
#endif
			cp += n;
			continue;
		}
		if (haveanswer) {
			if (n != host.h_length) {
				cp += n;
				continue;
			}
			if (class != getclass) {
				cp += n;
				continue;
			}
		} else {
			host.h_length = n;
			getclass = class;
			host.h_addrtype = (class == C_IN) ? AF_INET : AF_UNSPEC;
			if (!iquery) {
				host.h_name = bp;
				bp += strlen(bp) + 1;
			}
		}

		bp += sizeof (align) - ((u_long)bp % sizeof (align));

		if (bp + n >= &hostbuf[sizeof (hostbuf)]) {
#ifdef DEBUG
			if (_res.options & RES_DEBUG)
				printf("size (%d) too big\n", n);
#endif
			break;
		}
#ifdef SYSV
		memcpy((void *)(*hap++ = bp), (void *)cp, n);
#else
		bcopy(cp, *hap++ = bp, n);
#endif
		bp += n;
		cp += n;
		haveanswer++;
	}
	if (haveanswer) {
		*ap = NULL;
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
		*hap = NULL;
#else
		host.h_addr = h_addr_ptrs[0];
#endif
		return (&host);
	} else {
		h_errno = TRY_AGAIN;
		return ((struct hostent *) NULL);
	}
}

static struct hostent *_gethtbyname();

struct hostent *
res_gethostbyname(name)
	char *name;
{
	querybuf buf;
	register char *cp;
	int n;

	/*
	 * disallow names consisting only of digits/dots, unless
	 * they end in a dot.
	 */
	if (isdigit(name[0]))
		for (cp = name; /*EMPTY*/; ++cp) {
			if (!*cp) {
				if (*--cp == '.')
					break;
				h_errno = HOST_NOT_FOUND;
				return ((struct hostent *) NULL);
			}
			if (!isdigit(*cp) && *cp != '.')
				break;
		}

	if ((n = res_search(name, C_IN, T_A, buf.buf, sizeof (buf))) < 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("res_search failed\n");
#endif
		if (errno == ECONNREFUSED)
			return (_gethtbyname(name));
		else
			return ((struct hostent *) NULL);
	}
	return (getanswer(&buf, n, 0));
}

static struct hostent *_gethtbyaddr();

static struct hostent *
_getrhbyaddr(addr, len, type)
	char *addr;
	int len, type;
{
	int n;
	querybuf buf;
	register struct hostent *hp;
	char qbuf[MAXDNAME];

	if (type != AF_INET)
		return ((struct hostent *) NULL);
	(void) sprintf(qbuf, "%d.%d.%d.%d.in-addr.arpa",
		((unsigned)addr[3] & 0xff),
		((unsigned)addr[2] & 0xff),
		((unsigned)addr[1] & 0xff),
		((unsigned)addr[0] & 0xff));
	n = res_query(qbuf, C_IN, T_PTR, (u_char *)&buf, sizeof (buf));
	if (n < 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("res_query failed\n");
#endif
		if (errno == ECONNREFUSED)
			return (_gethtbyaddr(addr, len, type));
		return ((struct hostent *) NULL);
	}
	hp = getanswer(&buf, n, 1);
	if (hp == NULL)
		return ((struct hostent *) NULL);
	hp->h_addrtype = type;
	hp->h_length = len;
	h_addr_ptrs[0] = (char *)&host_addr;
	h_addr_ptrs[1] = (char *)0;
	host_addr = *(struct in_addr *)addr;
	return (hp);
}

/*
 * First we get what the PTR record says, but do an extra call
 * to gethostbyname() to make sure that someone is not trying to
 * spoof us.  Hopefully this is not done that often, so good
 * performance is not really an issue.
 */
struct hostent *
res_gethostbyaddr(addr, len, type)
	char	*addr;
	int	len;
	int	type;
{
	char		**a, hbuf[MAXHOSTNAMELEN];
	struct hostent	*hp, *hp2;

	if ((hp = _getrhbyaddr(addr, len, type)) == (struct hostent *)NULL)
		return ((struct hostent *)NULL);

	/* hang on to what we got as an answer */
	(void) strcpy(hbuf, hp->h_name);

	/* check to make sure by doing a forward query */
	if ((hp2 = res_gethostbyname(hbuf)) != (struct hostent *)NULL)
		for (a = hp2->h_addr_list; *a; a++)
#ifdef SYSV
			if (memcmp(*a, addr, hp2->h_length) == 0)
#else
			if (bcmp(*a, addr, hp2->h_length) == 0)
#endif
				return (hp2);

	/*
	 * we've been spoofed, make sure to log it.
	 * XXX - syslog needs a security priority level.
	 */
	syslog(LOG_NOTICE, "gethostbyaddr: %s != %s", hbuf,
		inet_ntoa(*(struct in_addr *)addr));
	return ((struct hostent *)NULL);
}

static void
_sethtent(int f)
{
	if (__res_no_hosts_fallback()) return;

	if (hostf == NULL)
		hostf = fopen(HOSTDB, "r");
	else
		rewind(hostf);
	stayopen |= f;
}

static void
_endhtent(void)
{
	if (__res_no_hosts_fallback()) return;

	if (hostf && !stayopen) {
		(void) fclose(hostf);
		hostf = NULL;
	}
}

static struct hostent *
_gethtent()
{
	char *p;
	register char *cp, **q;

	if (__res_no_hosts_fallback()) return(NULL);

	if (hostf == NULL && (hostf = fopen(HOSTDB, "r")) == NULL)
		return (NULL);
again:
	if ((p = fgets(hostbuf, BUFSIZ, hostf)) == NULL)
		return (NULL);
	if (*p == '#')
		goto again;
	cp = any(p, "#\n");
	if (cp == NULL)
		goto again;
	*cp = '\0';
	cp = any(p, " \t");
	if (cp == NULL)
		goto again;
	*cp++ = '\0';
	/* THIS STUFF IS INTERNET SPECIFIC */
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
	host.h_addr_list = host_addrs;
#endif
	host.h_addr = hostaddr;
	*((u_long *)host.h_addr) = inet_addr(p);
	host.h_length = sizeof (u_long);
	host.h_addrtype = AF_INET;
	while (*cp == ' ' || *cp == '\t')
		cp++;
	host.h_name = cp;
	q = host.h_aliases = host_aliases;
	cp = any(cp, " \t");
	if (cp != NULL)
		*cp++ = '\0';
	while (cp && *cp) {
		if (*cp == ' ' || *cp == '\t') {
			cp++;
			continue;
		}
		if (q < &host_aliases[MAXALIASES - 1])
			*q++ = cp;
		cp = any(cp, " \t");
		if (cp != NULL)
			*cp++ = '\0';
	}
	*q = NULL;
	return (&host);
}

static char *
any(cp, match)
	register char *cp;
	char *match;
{
	register char *mp, c;

	while (c = *cp) {
		for (mp = match; *mp; mp++)
			if (*mp == c)
				return (cp);
		cp++;
	}
	return ((char *)0);
}

static struct hostent *
_gethtbyname(name)
	char *name;
{
	register struct hostent *p;
	register char **cp;

	_sethtent(0);
	while (p = _gethtent()) {
		if (strcasecmp(p->h_name, name) == 0)
			break;
		for (cp = p->h_aliases; *cp != 0; cp++)
			if (strcasecmp(*cp, name) == 0)
				goto found;
	}
found:
	_endhtent();
	return (p);
}

static struct hostent *
_gethtbyaddr(addr, len, type)
	char *addr;
	int len, type;
{
	register struct hostent *p;

	_sethtent(0);
	while (p = _gethtent())
#ifdef SYSV
		if (p->h_addrtype == type && !memcmp(p->h_addr, addr, len))
#else
		if (p->h_addrtype == type && !bcmp(p->h_addr, addr, len))
#endif
			break;
	_endhtent();
	return (p);
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Gary Mills
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <sys/types.h>
#include <sys/sockio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <stropts.h>
#include <arpa/nameser.h>
#include <resolv.h>

#include <netinet/in.h>
#include <net/if.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>

/*
 * Undocumented external function in libnsl
 */
extern int
getdomainname(char *, int);

#define	MAXIFS	256

/*
 * Resolver state default settings
 */

struct state _res = {
	RES_TIMEOUT,		/* retransmition time interval */
	4,				/* number of times to retransmit */
	RES_DEFAULT,		/* options flags */
	1,				/* number of name servers */
};

/*
 * Set up default settings.  If the configuration file exist, the values
 * there will have precedence.  Otherwise, the server address is set to
 * INADDR_LOOPBACK and the default domain name comes from the gethostname().
 * BUT if the NIS/RPC domain name is set, that is used if all else fails.
 *
 * The configuration file should only be used if you want to redefine your
 * domain or run without a server on your machine.
 *
 * Note the user can always override then domain name with the environment
 * variable LOCALDOMAIN which has absolute priority.
 *
 *
 * Return 0 if completes successfully, -1 on error
 */
int
res_init(void)
{
	register FILE *fp;
	register char *cp, **pp;
	register int n;
	char buf[BUFSIZ];
	int nserv = 0;    /* number of nameserver records read from file */
	int haveenv = 0;
	int havesearch = 0;

	_res.nsaddr.sin_addr.s_addr =  htonl(INADDR_LOOPBACK); /* INADDR_ANY */
	_res.nsaddr.sin_family = AF_INET;
	_res.nsaddr.sin_port = htons(NAMESERVER_PORT);
	_res.nscount = 1;

#ifdef SIOCGIFNUM
	{	int numifs, s, n, int_up;
		struct ifconf ifc;
		register struct ifreq *ifrp;
		struct ifreq ifr;
		unsigned bufsize;
		unsigned int flags;
		char *buf;

		if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
			perror("socket");
			return (-1);
		}
		if (ioctl(s, SIOCGIFNUM, (char *)&numifs) < 0) {
			numifs = MAXIFS;
		}
		bufsize = numifs * sizeof (struct ifreq);
		buf = (char *)malloc(bufsize);
		if (buf == NULL) {
			perror("out of memory");
			(void) close(s);
			return (-1);
		}
		ifc.ifc_len = bufsize;
		ifc.ifc_buf = buf;
		if (ioctl(s, SIOCGIFCONF, (char *)&ifc) < 0) {
			perror("ifconfig: SIOCGIFCONF");
			(void) close(s);
			free(buf);
			return (-1);
		}

		int_up = 0;
		ifrp = ifc.ifc_req;
		for (n = ifc.ifc_len / sizeof (struct ifreq); n > 0;
								n--, ifrp++) {
			(void) memset((void *) &ifr, 0, sizeof (ifr));
			strncpy(ifr.ifr_name, ifrp->ifr_name,
							sizeof (ifr.ifr_name));
			if (ioctl(s, SIOCGIFFLAGS, (char *)&ifr) < 0) {
				perror("SIOCGIFFLAGS");
				(void) close(s);
				free(buf);
				return (-1);
			}
			flags = ifr.ifr_flags;
			/* we are looking for a non-loopback interface */
			if ((flags & IFF_UP) && ((flags & IFF_LOOPBACK) == 0))
				int_up = 1;
		}
		(void) close(s);
		free(buf);
		if (int_up == 0) /* all the non-LOOPBACK interfaces are DOWN */
			return (-1);
	}
#endif /* SIOCGIFNUM */


	/*
	 * for the benefit of hidden NIS domains, we use the same procedure
	 * as sendmail: convert leading + to dot, then drop to first dot
	 */
	(void) getdomainname(buf, BUFSIZ);
	if (buf[0] == '+')
		buf[0] = '.';
#ifdef SYSV
	cp = strchr(buf, (int)'.');
#else
	cp = index(buf, '.');
#endif
	if (cp == NULL)
		strcpy(_res.defdname, buf);
	else
		strcpy(_res.defdname, cp+1);

	/* Allow user to override the local domain definition */
	if ((cp = getenv("LOCALDOMAIN")) != NULL) {
	(void) strncpy(_res.defdname, cp, sizeof (_res.defdname));
	haveenv++;
	}

	if ((fp = fopen(_PATH_RESCONF, "r")) != NULL) {
	/* read the config file */
	while (fgets(buf, sizeof (buf), fp) != NULL) {
	    /* read default domain name */
	    if (!strncmp(buf, "domain", sizeof ("domain") - 1)) {
		if (haveenv)	/* skip if have from environ */
			    continue;
		cp = buf + sizeof ("domain") - 1;
		while (*cp == ' ' || *cp == '\t')
		    cp++;
		if ((*cp == '\0') || (*cp == '\n'))
		    continue;
		(void) strncpy(_res.defdname, cp, sizeof (_res.defdname) - 1);
#ifdef SYSV
		if ((cp = strchr(_res.defdname, (int)'\n')) != NULL)
#else
		if ((cp = index(_res.defdname, '\n')) != NULL)
#endif
		    *cp = '\0';
		havesearch = 0;
		continue;
	    }
	    /* set search list */
	    if (!strncmp(buf, "search", sizeof ("search") - 1)) {
		if (haveenv)	/* skip if have from environ */
		    continue;
		cp = buf + sizeof ("search") - 1;
		while (*cp == ' ' || *cp == '\t')
		    cp++;
		if ((*cp == '\0') || (*cp == '\n'))
		    continue;
		(void) strncpy(_res.defdname, cp, sizeof (_res.defdname) - 1);
#ifdef SYSV
		if ((cp = strchr(_res.defdname, (int)'\n')) != NULL)
#else
		if ((cp = index(_res.defdname, '\n')) != NULL)
#endif
		    *cp = '\0';
		/*
		 * Set search list to be blank-separated strings
		 * on rest of line.
		 */
		cp = _res.defdname;
		pp = _res.dnsrch;
		*pp++ = cp;
		for (n = 0; *cp && pp < _res.dnsrch + MAXDNSRCH; cp++) {
		    if (*cp == ' ' || *cp == '\t') {
			*cp = 0;
			n = 1;
		    } else if (n) {
			*pp++ = cp;
			n = 0;
		    }
		}
		/* null terminate last domain if there are excess */
		while (*cp != '\0' && *cp != ' ' && *cp != '\t')
		    cp++;
		*cp = '\0';
		*pp++ = 0;
		havesearch = 1;
		continue;
	    }
	    /* read nameservers to query */
	    if (!strncmp(buf, "nameserver", sizeof ("nameserver") - 1) &&
		(nserv < MAXNS)) {
		cp = buf + sizeof ("nameserver") - 1;
		while (*cp == ' ' || *cp == '\t')
		    cp++;
		if ((*cp == '\0') || (*cp == '\n'))
		    continue;
		if ((_res.nsaddr_list[nserv].sin_addr.s_addr =
				inet_addr(cp)) == (unsigned) -1) {
		    _res.nsaddr_list[n].sin_addr.s_addr = INADDR_ANY;
		    continue;
		}
		_res.nsaddr_list[nserv].sin_family = AF_INET;
		_res.nsaddr_list[nserv].sin_port = htons(NAMESERVER_PORT);
		nserv++;
		continue;
	    }
	}
	if (nserv > 1)
	    _res.nscount = nserv;
	(void) fclose(fp);
	}
	if (_res.defdname[0] == 0) {
	if (gethostname(buf, sizeof (_res.defdname)) == 0 &&
#ifdef SYSV
	    (cp = strchr(buf, (int)'.')))
#else
	    (cp = index(buf, '.')))
#endif
		(void) strcpy(_res.defdname, cp + 1);
	}

	/* find components of local domain that might be searched */
	if (havesearch == 0) {
	pp = _res.dnsrch;
	*pp++ = _res.defdname;
	for (cp = _res.defdname, n = 0; *cp; cp++)
	    if (*cp == '.')
		n++;
	cp = _res.defdname;
	for (; n >= LOCALDOMAINPARTS && pp < _res.dnsrch + MAXDFLSRCH; n--) {
#ifdef SYSV
	    cp = strchr(cp, (int)'.');
#else
	    cp = index(cp, '.');
#endif
	    *pp++ = ++cp;
	}
	*pp++ = 0;
	}
	_res.options |= RES_INIT;
	return (0);
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Gary Mills
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <netdb.h>
#include "crossl.h"

/*
 * Kludge to time out quickly if there is no /etc/resolv.conf
 * and a TCP connection to the local DNS server fails.
 *
 * Moved function from res_send.c to res_mkquery.c.  This
 * solves a long timeout problem with nslookup.
 *
 * __areweinnamed is needed because there is a possibility that the
 * user might do bad things to resolv.conf and cause in.named to call
 * _confcheck and deadlock the server.
 */

int __areweinnamed()
{
	return (0);
}

static int _confcheck()
{
	int ns;
	struct stat rc_stat;
	struct sockaddr_in ns_sin;


	/* First, we check to see if /etc/resolv.conf exists.
	 * If it doesn't, then localhost is mostlikely to be
	 * the nameserver.
	 */
	if (stat(_PATH_RESCONF, &rc_stat) == -1 && errno == ENOENT) {

		/* Next, we check to see if _res.nsaddr is set to loopback.
		 * If it isn't, it has been altered by the application
		 * explicitly and we then want to bail with success.
		 */
		if (__areweinnamed())
			return (0);

		if (_res.nsaddr.sin_addr.S_un.S_addr == htonl(INADDR_LOOPBACK)) {

			/* Lastly, we try to connect to the TCP port of the
			 * nameserver.  If this fails, then we know that
			 * DNS is misconfigured and we can quickly exit.
			 */
			ns = socket(AF_INET, SOCK_STREAM, 0);
			IN_SET_LOOPBACK_ADDR(&ns_sin);
			ns_sin.sin_port = htons(NAMESERVER_PORT);
			if (connect(ns, (struct sockaddr *) &ns_sin,
				    sizeof ns_sin) == -1) {
				(void) close(ns);
				return(-1);
			}
			else {
				(void) close(ns);
				return(0);
			}
		}

		return(0);
	}

	return (0);
}

/*
 * Form all types of queries.
 * Returns the size of the result or -1.
 */
int
res_mkquery(op, dname, class, type, data, datalen, newrr, buf, buflen)
	int op;			/* opcode of query */
	char *dname;		/* domain name */
	int class, type;	/* class and type of query */
	char *data;		/* resource record data */
	int datalen;		/* length of data */
	struct rrec *newrr;	/* new rr for modify or append */
	char *buf;		/* buffer to put query */
	int buflen;		/* size of buffer */
{
	register HEADER *hp;
	register u_char *cp;
	register int n;
	u_char *dnptrs[10], **dpp, **lastdnptr;

#ifdef DEBUG
	if (_res.options & RES_DEBUG)
		printf("res_mkquery(%d, %s, %d, %d)\n", op, dname, class, type);
#endif /* DEBUG */

	/*
	 * Check to see if we can bailout quickly.
	 * Also rerun res_init if we failed in the past.
	 */

	if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
		h_errno = NO_RECOVERY;
		return(-1);
	}

	if (_confcheck() == -1) {
		_res.options &= ~RES_INIT;
		h_errno = NO_RECOVERY;
		return(-1);
	}

	/*
	 * Initialize header fields.
	 */
	if ((buf == NULL) || (buflen < sizeof (HEADER)))
		return (-1);
#ifdef SYSV
	(void) memset(buf, 0, sizeof (HEADER));
#else
	bzero(buf, sizeof (HEADER));
#endif
	hp = (HEADER *) buf;
	hp->id = htons(++_res.id);
	hp->opcode = op;
	hp->pr = (_res.options & RES_PRIMARY) != 0;
	hp->rd = (_res.options & RES_RECURSE) != 0;
	hp->rcode = NOERROR;
	cp = (u_char *)(buf + sizeof (HEADER));
	buflen -= sizeof (HEADER);
	dpp = dnptrs;
	*dpp++ = (u_char *)buf;
	*dpp++ = NULL;
	lastdnptr = dnptrs + sizeof (dnptrs) / sizeof (dnptrs[0]);
	/*
	 * perform opcode specific processing
	 */
	switch (op) {
	case QUERY:
		if ((buflen -= QFIXEDSZ) < 0)
			return (-1);
		if ((n = dn_comp((u_char *)dname, cp, buflen,
		    dnptrs, lastdnptr)) < 0)
			return (-1);
		cp += n;
		buflen -= n;
		putshort(type, cp);
		cp += sizeof (u_short);
		putshort(class, cp);
		cp += sizeof (u_short);
		hp->qdcount = htons(1);
		if (op == QUERY || data == NULL)
			break;
		/*
		 * Make an additional record for completion domain.
		 */
		buflen -= RRFIXEDSZ;
		if ((n = dn_comp((u_char *)data, cp, buflen,
		    dnptrs, lastdnptr)) < 0)
			return (-1);
		cp += n;
		buflen -= n;
		putshort(T_NULL, cp);
		cp += sizeof (u_short);
		putshort(class, cp);
		cp += sizeof (u_short);
		putlong(0, cp);
		cp += sizeof (u_long);
		putshort(0, cp);
		cp += sizeof (u_short);
		hp->arcount = htons(1);
		break;

	case IQUERY:
		/*
		 * Initialize answer section
		 */
		if (buflen < 1 + RRFIXEDSZ + datalen)
			return (-1);
		*cp++ = '\0';	/* no domain name */
		putshort(type, cp);
		cp += sizeof (u_short);
		putshort(class, cp);
		cp += sizeof (u_short);
		putlong(0, cp);
		cp += sizeof (u_long);
		putshort(datalen, cp);
		cp += sizeof (u_short);
		if (datalen) {
#ifdef SYSV
			(void) memcpy((void *)cp, (void *)data, datalen);
#else
			bcopy(data, cp, datalen);
#endif
			cp += datalen;
		}
		hp->ancount = htons(1);
		break;

#ifdef ALLOW_UPDATES
	/*
	 * For UPDATEM/UPDATEMA, do UPDATED/UPDATEDA followed by UPDATEA
	 * (Record to be modified is followed by its replacement in msg.)
	 */
	case UPDATEM:
	case UPDATEMA:

	case UPDATED:
		/*
		 * The res code for UPDATED and UPDATEDA is the same; user
		 * calls them differently: specifies data for UPDATED; server
		 * ignores data if specified for UPDATEDA.
		 */
	case UPDATEDA:
		buflen -= RRFIXEDSZ + datalen;
		if ((n = dn_comp((u_char *)dname, cp, buflen,
		    dnptrs, lastdnptr)) < 0)
			return (-1);
		cp += n;
		putshort(type, cp);
		cp += sizeof (u_short);
		putshort(class, cp);
		cp += sizeof (u_short);
		putlong(0, cp);
		cp += sizeof (u_long);
		putshort(datalen, cp);
		cp += sizeof (u_short);
		if (datalen) {
#ifdef SYSV
			memcpy((void *)cp, (void *)data, datalen);
#else
			bcopy(data, cp, datalen);
#endif
			cp += datalen;
		}
		if ((op == UPDATED) || (op == UPDATEDA)) {
			hp->ancount = htons(0);
			break;
		}
		/* Else UPDATEM/UPDATEMA, so drop into code for UPDATEA */

	case UPDATEA:	/* Add new resource record */
		buflen -= RRFIXEDSZ + datalen;
		if ((n = dn_comp((u_char *)dname, cp, buflen,
		    dnptrs, lastdnptr)) < 0)
			return (-1);
		cp += n;
		putshort(newrr->r_type, cp);
		cp += sizeof (u_short);
		putshort(newrr->r_class, cp);
		cp += sizeof (u_short);
		putlong(0, cp);
		cp += sizeof (u_long);
		putshort(newrr->r_size, cp);
		cp += sizeof (u_short);
		if (newrr->r_size) {
#ifdef SYSV
			memcpy((void *)cp, newrr->r_data, newrr->r_size);
#else
			bcopy(newrr->r_data, cp, newrr->r_size);
#endif
			cp += newrr->r_size;
		}
		hp->ancount = htons(0);
		break;

#endif /* ALLOW_UPDATES */
	}
	return ((char *)cp - buf);
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Gary Mills
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <ctype.h>
#include <netdb.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include "crossl.h"

#if PACKETSZ > 1024
#define	MAXPACKET	PACKETSZ
#else
#define	MAXPACKET	1024
#endif

/*
 * Formulate a normal query, send, and await answer.
 * Returned answer is placed in supplied buffer "answer".
 * Perform preliminary check of answer, returning success only
 * if no error is indicated and the answer count is nonzero.
 * Return the size of the response on success, -1 on error.
 * Error number is left in h_errno.
 * Caller must parse answer and determine whether it answers the question.
 */
int
res_query(name, class, type, answer, anslen)
	char *name;		/* domain name */
	int class, type;	/* class and type of query */
	u_char *answer;		/* buffer to put answer */
	int anslen;		/* size of answer buffer */
{
	char buf[MAXPACKET];
	HEADER *hp;
	int n;

	if ((_res.options & RES_INIT) == 0 && res_init() == -1)
		return (-1);
#ifdef DEBUG
	if (_res.options & RES_DEBUG)
		printf("res_query(%s, %d, %d)\n", name, class, type);
#endif
	n = res_mkquery(QUERY, name, class, type, (char *)NULL, 0, NULL,
	    buf, sizeof (buf));

	if (n <= 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("res_query: mkquery failed\n");
#endif
		h_errno = NO_RECOVERY;
		return (n);
	}
	n = res_send(buf, n, (char *)answer, anslen);
	if (n < 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("res_query: send error\n");
#endif
		h_errno = TRY_AGAIN;
		return (n);
	}

	hp = (HEADER *) answer;
	if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("rcode = %d, ancount=%d\n", hp->rcode,
			    ntohs(hp->ancount));
#endif
		switch (hp->rcode) {
			case NXDOMAIN:
				h_errno = HOST_NOT_FOUND;
				break;
			case SERVFAIL:
				h_errno = TRY_AGAIN;
				break;
			case NOERROR:
				h_errno = NO_DATA;
				break;
			case FORMERR:
			case NOTIMP:
			case REFUSED:
			default:
				h_errno = NO_RECOVERY;
				break;
		}
		return (-1);
	}
	if (hp->rcode == NOERROR && ntohs(hp->ancount) > 0)
		h_errno = 0;
	return (n);
}

/*
 * Formulate a normal query, send, and retrieve answer in supplied buffer.
 * Return the size of the response on success, -1 on error.
 * If enabled, implement search rules until answer or unrecoverable failure
 * is detected.  Error number is left in h_errno.
 * Only useful for queries in the same name hierarchy as the local host
 * (not, for example, for host address-to-name lookups in domain in-addr.arpa).
 */
int
res_search(name, class, type, answer, anslen)
	char *name;		/* domain name */
	int class, type;	/* class and type of query */
	u_char *answer;		/* buffer to put answer */
	int anslen;		/* size of answer */
{
	register char *cp, **domain;
	int n, ret, got_nodata = 0;
	char *hostalias();

	if ((_res.options & RES_INIT) == 0 && res_init() == -1)
		return (-1);

	errno = 0;
	h_errno = HOST_NOT_FOUND;		/* default, if we never query */
	for (cp = name, n = 0; *cp; cp++)
		if (*cp == '.')
			n++;
	if (n == 0 && (cp = hostalias(name)))
		return (res_query(cp, class, type, answer, anslen));

	/*
	 * We do at least one level of search if
	 *	- there is no dot and RES_DEFNAME is set, or
	 *	- there is at least one dot, there is no trailing dot,
	 *	  and RES_DNSRCH is set.
	 */
	if ((n == 0 && _res.options & RES_DEFNAMES) ||
		(n != 0 && *--cp != '.' && _res.options & RES_DNSRCH)) {
		for (domain = _res.dnsrch; *domain; domain++) {
			ret = res_querydomain(name, *domain, class, type,
							answer, anslen);
			if (ret > 0)
				return (ret);
		/*
		 * If no server present, give up.
		 * If name isn't found in this domain,
		 * keep trying higher domains in the search list
		 * (if that's enabled).
		 * On a NO_DATA error, keep trying, otherwise
		 * a wildcard entry of another type could keep us
		 * from finding this entry higher in the domain.
		 * If we get some other error (negative answer or
		 * server failure), then stop searching up,
		 * but try the input name below in case it's fully-qualified.
		 */
			if (errno == ECONNREFUSED) {
				h_errno = TRY_AGAIN;
				return (-1);
			}
			if (h_errno == NO_DATA)
				got_nodata++;
			if ((h_errno != HOST_NOT_FOUND && h_errno != NO_DATA) ||
				(_res.options & RES_DNSRCH) == 0)
				break;
		}
	}
	/*
	 * If the search/default failed, try the name as fully-qualified,
	 * but only if it contained at least one dot (even trailing).
	 * This is purely a heuristic; we assume that any reasonable query
	 * about a top-level domain (for servers, SOA, etc) will not use
	 * res_search.
	 */
	if (n && (ret = res_querydomain(name, (char *)NULL, class, type,
	    answer, anslen)) > 0)
		return (ret);
	if (got_nodata)
		h_errno = NO_DATA;
	return (-1);
}

/*
 * Perform a call on res_query on the concatenation of name and domain,
 * removing a trailing dot from name if domain is NULL.
 */
int
res_querydomain(name, domain, class, type, answer, anslen)
	char *name, *domain;
	int class, type;	/* class and type of query */
	u_char *answer;		/* buffer to put answer */
	int anslen;		/* size of answer */
{
	char nbuf[2*MAXDNAME+2];
	char *longname = nbuf;
	int n;

#ifdef DEBUG
	if (_res.options & RES_DEBUG) {
		if (domain == (char *)NULL)
			printf("res_querydomain(%s, NULL, %d, %d)\n",
					    name, class, type);
		else
			printf("res_querydomain(%s, %s, %d, %d)\n",
					    name, domain, class, type);
	}
#endif
	if (domain == NULL) {
		/*
		 * Check for trailing '.';
		 * copy without '.' if present.
		 */
		n = strlen(name) - 1;
		if (name[n] == '.' && n < sizeof (nbuf) - 1) {
#ifdef SYSV
			memcpy((void *)nbuf, (void *)name, n);
#else
			bcopy(name, nbuf, n);
#endif
			nbuf[n] = '\0';
		} else
			longname = name;
	} else
		(void) sprintf(nbuf, "%.*s.%.*s",
		    MAXDNAME, name, MAXDNAME, domain);

	return (res_query(longname, class, type, answer, anslen));
}

char *
hostalias(name)
	register char *name;
{
	register char *C1, *C2;
	FILE *fp;
	char *file;
	char buf[BUFSIZ];
	static char abuf[MAXDNAME];

	file = getenv("HOSTALIASES");
	if (file == NULL || (fp = fopen(file, "r")) == NULL)
		return (NULL);
	buf[sizeof (buf) - 1] = '\0';
	while (fgets(buf, sizeof (buf), fp)) {
		for (C1 = buf; *C1 && !isspace(*C1); ++C1);
		if (!*C1)
			break;
		*C1 = '\0';
		if (!strcasecmp(buf, name)) {
			while (isspace(*++C1));
			if (!*C1)
				break;
			for (C2 = C1 + 1; *C2 && !isspace(*C2); ++C2);
			abuf[sizeof (abuf) - 1] = *C2 = '\0';
			(void) strncpy(abuf, C1, sizeof (abuf) - 1);
			fclose(fp);
			return (abuf);
		}
	}
	fclose(fp);
	return (NULL);
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Gary Mills
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * Send query to name server and wait for reply.
 */

#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <resolv.h>
#include "crossl.h"

/*
 * Undocumented external function in libsocket
 */
extern int
_socket(int, int, int);

static int s = -1;	/* socket used for communications */
#if	BSD >= 43
static struct sockaddr no_addr;
#endif /* BSD */


#ifndef FD_SET
#define	NFDBITS		32
#define	FD_SETSIZE	32
#define	FD_SET(n, p)	((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
#define	FD_CLR(n, p)	((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
#define	FD_ISSET(n, p)	((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
#ifdef SYSV
#define	FD_ZERO(p)	(void) memset((void *)(p), 0, sizeof (*(p)))
#else
#define	FD_ZERO(p)	bzero((char *)(p), sizeof (*(p)))
#endif
#endif

/*
 * 1247019: Kludge to time out quickly if there is no /etc/resolv.conf
 * and a TCP connection to the local DNS server fails.
 */

static int _confcheck()
{
	int ns;
	struct stat rc_stat;
	struct sockaddr_in ns_sin;


	/* First, we check to see if /etc/resolv.conf exists.
	 * If it doesn't, then localhost is mostlikely to be
	 * the nameserver.
	 */
	if (stat(_PATH_RESCONF, &rc_stat) == -1 && errno == ENOENT) {

		/* Next, we check to see if _res.nsaddr is set to loopback.
		 * If it isn't, it has been altered by the application
		 * explicitly and we then want to bail with success.
		 */
		if (_res.nsaddr.sin_addr.S_un.S_addr == htonl(INADDR_LOOPBACK)) {

			/* Lastly, we try to connect to the TCP port of the
			 * nameserver.  If this fails, then we know that
			 * DNS is misconfigured and we can quickly exit.
			 */
			ns = socket(AF_INET, SOCK_STREAM, 0);
			IN_SET_LOOPBACK_ADDR(&ns_sin);
			ns_sin.sin_port = htons(NAMESERVER_PORT);
			if (connect(ns, (struct sockaddr *) &ns_sin,
				    sizeof ns_sin) == -1) {
				close(ns);
				return(-1);
			}
			else {
				close(ns);
				return(0);
			}
		}

		return(0);
	}

	return (0);
}

int
res_send(buf, buflen, answer, anslen)
	char *buf;
	int buflen;
	char *answer;
	int anslen;
{
	register int n;
	int try, v_circuit, resplen, ns;
	int gotsomewhere = 0;
#if	BSD >= 43
	int connected = 0;
#endif /* BSD */
	int connreset = 0;
	u_short id, len;
	char *cp;
	fd_set dsmask;
	struct timeval timeout;
	HEADER *hp = (HEADER *) buf;
	HEADER *anhp = (HEADER *) answer;
	struct iovec iov[2];
	int terrno = ETIMEDOUT;
	char junk[512];

#ifdef DEBUG
	if (_res.options & RES_DEBUG) {
		printf("res_send()\n");
		p_query(buf);
	}
#endif
	if (!(_res.options & RES_INIT))
		if (res_init() == -1) {
			return (-1);
		}

	/* 1247019: Check to see if we can bailout quickly. */
	if (_confcheck() == -1)
	    return(-1);

	v_circuit = (_res.options & RES_USEVC) || buflen > PACKETSZ;
	id = hp->id;
	/*
	 * Send request, RETRY times, or until successful
	 */
	for (try = 0; try < _res.retry; try++) {
		for (ns = 0; ns < _res.nscount; ns++) {
#ifdef DEBUG
			if (_res.options & RES_DEBUG)
				printf("Querying server (# %d) address = %s\n",
				ns+1, inet_ntoa(_res.nsaddr_list[ns].sin_addr));
#endif
		usevc:
			if (v_circuit) {
				int truncated = 0;

				/*
				 * Use virtual circuit;
				 * at most one attempt per server.
				 */
				try = _res.retry;
				if (s < 0) {
					s = _socket(AF_INET, SOCK_STREAM, 0);
					if (s < 0) {
						terrno = errno;
#ifdef DEBUG
						if (_res.options & RES_DEBUG) {
						perror("socket (vc) failed");
						}
#endif
						continue;
					}
					if (connect(s, (struct sockaddr *) &_res.nsaddr_list[ns],
						sizeof (struct sockaddr)) < 0) {
						terrno = errno;
#ifdef DEBUG
						if (_res.options & RES_DEBUG) {
						perror("connect failed");
						}
#endif
						(void) close(s);
						s = -1;
						continue;
					}
				}
				/*
				 * Send length & message
				 */
				len = htons((u_short)buflen);
				iov[0].iov_base = (caddr_t)&len;
				iov[0].iov_len = sizeof (len);
				iov[1].iov_base = buf;
				iov[1].iov_len = buflen;
				if (writev(s, iov, 2) != sizeof (len) +
								buflen) {
					terrno = errno;
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						perror("write failed");
#endif
					(void) close(s);
					s = -1;
					continue;
				}
				/*
				 * Receive length & response
				 */
				cp = answer;
				len = sizeof (short);
				while (len != 0 && (n = read
					(s, (char *)cp, (int)len)) > 0) {
					cp += n;
					len -= n;
				}
				if (n <= 0) {
					terrno = errno;
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						perror("read failed");
#endif
					(void) close(s);
					s = -1;
				/*
				 * A long running process might get its TCP
				 * connection reset if the remote server was
				 * restarted.  Requery the server instead of
				 * trying a new one.  When there is only one
				 * server, this means that a query might work
				 * instead of failing.  We only allow one reset
				 * per query to prevent looping.
				 */
					if (terrno == ECONNRESET &&
							!connreset) {
						connreset = 1;
						ns--;
					}
					continue;
				}
				cp = answer;
				if ((resplen = ntohs(*(u_short *)cp)) >
								anslen) {
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						fprintf(stderr,
							"response truncated\n");
#endif
					len = anslen;
					truncated = 1;
				} else
					len = resplen;
				while (len != 0 &&
					(n = read(s, (char *)cp,
							(int)len)) > 0) {
					cp += n;
					len -= n;
				}
				if (n <= 0) {
					terrno = errno;
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						perror("read failed");
#endif
					(void) close(s);
					s = -1;
					continue;
				}
				if (truncated) {
					/*
					 * Flush rest of answer
					 * so connection stays in synch.
					 */
					anhp->tc = 1;
					len = resplen - anslen;
					/*
					 * set the value of resplen to anslen,
					 * this is done because the caller
					 * assumes resplen contains the size of
					 * message read into the "answer" buffer
					 * passed in.
					 */
					resplen = anslen;

					while (len != 0) {
						n = (len > sizeof (junk) ?
							sizeof (junk) : len);
						if ((n = read(s, junk, n)) > 0)
							len -= n;
						else
							break;
					}
				}
			} else {
				/*
				 * Use datagrams.
				 */
				if (s < 0) {
					s = _socket(AF_INET, SOCK_DGRAM, 0);
					if (s < 0) {
						terrno = errno;
#ifdef DEBUG
						if (_res.options & RES_DEBUG) {
						perror("socket (dg) failed");
						}
#endif
						continue;
					}
				}
#if	BSD >= 43
			/*
			 * I'm tired of answering this question, so:
			 * On a 4.3BSD+ machine (client and server,
			 * actually), sending to a nameserver datagram
			 * port with no nameserver will cause an
			 * ICMP port unreachable message to be returned.
			 * If our datagram socket is "connected" to the
			 * server, we get an ECONNREFUSED error on the next
			 * socket operation, and select returns if the
			 * error message is received.  We can thus detect
			 * the absence of a nameserver without timing out.
			 * If we have sent queries to at least two servers,
			 * however, we don't want to remain connected,
			 * as we wish to receive answers from the first
			 * server to respond.
			 */
				if (_res.nscount == 1 ||
						(try == 0 && ns == 0)) {
					/*
					 * Don't use connect if we might
					 * still receive a response
					 * from another server.
					 */
					if (connected == 0) {
						if (connect(s,
						(struct sockaddr *) &_res.nsaddr_list[ns],
						sizeof (struct sockaddr)) < 0) {
#ifdef DEBUG
							if (_res.options &
								RES_DEBUG) {
							perror("connect");
							}
#endif
							continue;
						}
						connected = 1;
					}
					if (send(s, buf, buflen, 0) != buflen) {
#ifdef DEBUG
						if (_res.options & RES_DEBUG)
							perror("send");
#endif
						continue;
					}
				} else {
					/*
					 * Disconnect if we want to listen for
					 * responses from more than one server.
					 */
					if (connected) {
						(void) connect(s, &no_addr,
							sizeof (no_addr));
						connected = 0;
					}
#endif /* BSD */
					if (sendto(s, buf, buflen, 0,
						(struct sockaddr *) &_res.nsaddr_list[ns],
					sizeof (struct sockaddr)) != buflen) {
#ifdef DEBUG
						if (_res.options & RES_DEBUG)
							perror("sendto");
#endif
						continue;
					}
#if	BSD >= 43
				}
#endif

				/*
				 * Wait for reply
				 */
				timeout.tv_sec = (_res.retrans << try);
				if (try > 0)
					timeout.tv_sec /= _res.nscount;
				if (timeout.tv_sec <= 0)
					timeout.tv_sec = 1;
				timeout.tv_usec = 0;
wait:
				FD_ZERO(&dsmask);
				FD_SET(s, &dsmask);
				n = select(s+1, &dsmask, (fd_set *)NULL,
						(fd_set *)NULL, &timeout);
				if (n < 0) {
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						perror("select");
#endif
					continue;
				}
				if (n == 0) {
					/*
					 * timeout
					 */
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						printf("timeout\n");
#endif
#if BSD >= 43
					gotsomewhere = 1;
#endif
					continue;
				}
				if ((resplen = recv(s, answer, anslen, 0))
									<= 0) {
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						perror("recvfrom");
#endif
					continue;
				}
				gotsomewhere = 1;
				if (id != anhp->id) {
					/*
					 * response from old query, ignore it
					 */
#ifdef DEBUG
					if (_res.options & RES_DEBUG) {
						printf("old answer:\n");
						p_query(answer);
					}
#endif
					goto wait;
				}
				if (!(_res.options & RES_IGNTC) && anhp->tc) {
					/*
					 * get rest of answer;
					 * use TCP with same server.
					 */
#ifdef DEBUG
					if (_res.options & RES_DEBUG)
						printf("truncated answer\n");
#endif
					(void) close(s);
					s = -1;
					v_circuit = 1;
					goto usevc;
				}
			}
#ifdef DEBUG
			if (_res.options & RES_DEBUG) {
				printf("got answer:\n");
				p_query(answer);
			}
#endif
		/*
		 * If using virtual circuits, we assume that the first server
		 * is preferred * over the rest (i.e. it is on the local
		 * machine) and only keep that one open.
		 * If we have temporarily opened a virtual circuit,
		 * or if we haven't been asked to keep a socket open,
		 * close the socket.
		 */
			if ((v_circuit &&
				((_res.options & RES_USEVC) == 0 || ns != 0)) ||
				(_res.options & RES_STAYOPEN) == 0) {
				(void) close(s);
				s = -1;
			}
			return (resplen);
		}
	}
	if (s >= 0) {
		(void) close(s);
		s = -1;
	}
	if (v_circuit == 0)
		if (gotsomewhere == 0)
			errno = ECONNREFUSED;	/* no nameservers found */
		else
			errno = ETIMEDOUT;	/* no answer obtained */
	else
		errno = terrno;
	return (-1);
}

/*
 * This routine is for closing the socket if a virtual circuit is used and
 * the program wants to close it.  This provides support for endhostent()
 * which expects to close the socket.
 *
 * This routine is not expected to be user visible.
 */
void
_res_close()
{
	if (s != -1) {
		(void) close(s);
		s = -1;
	}
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2015 Gary Mills
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include <sys/types.h>
#include <arpa/nameser.h>
#include <netinet/in.h>
#include <resolv.h>
#include "crossl.h"

void
res_sethostent(stayopen)
int stayopen;
{
	if (stayopen)
		_res.options |= RES_STAYOPEN | RES_USEVC;
}

void
res_endhostent()
{
	_res.options &= ~(RES_STAYOPEN | RES_USEVC);
	_res_close();
}

void
res_sethostfile(name)
char *name;
{
#ifdef lint
name = name;
#endif
}
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 1989 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/

/*
 * Portions of this source code were derived from Berkeley 4.3 BSD
 * under license from the Regents of the University of California.
 */

/*
 * Global defines and variables for resolver stub.
 */

#ifndef	_RESOLV_H
#define	_RESOLV_H

#include <stdio.h>

#ifdef	__cplusplus
extern "C" {
#endif

/*
 * Resolver configuration file.
 * Normally not present, but may contain the address of the
 * inital name server(s) to query and the domain search list.
 */

#ifndef	_PATH_RESCONF
#define	_PATH_RESCONF	"/etc/resolv.conf"
#endif

#define	ADDRSORT	1		/* enable the address-sorting option */
#define	MAXADDR		10		/* max # addresses to sort by */

#define	MAXNS		3		/* max # name servers we'll track */
#define	MAXDFLSRCH	3		/* # default domain levels to try */
#define	MAXDNSRCH	6		/* max # default domain levels to try */
#define	LOCALDOMAINPARTS 2		/* min levels in name that is "local" */

#define	RES_TIMEOUT	6		/* seconds between retries */

struct state {
	int	retrans;		/* retransmition time interval */
	int	retry;			/* number of times to retransmit */
	long	options;		/* option flags - see below. */
	int	nscount;		/* number of name servers */
	struct	sockaddr_in nsaddr_list[MAXNS];	/* address of name server */
#define	nsaddr	nsaddr_list[0]		/* for backward compatibility */
	u_short	id;			/* current packet id */
	char	defdname[MAXDNAME];	/* default domain */
	char	*dnsrch[MAXDNSRCH+1];	/* components of domain to search */
	int	ascount;		/* number of addresses */
	struct  in_addr sort_list[MAXADDR]; /* address sorting list */
};

/*
 * Resolver options
 */
#define	RES_INIT	0x0001		/* address initialized */
#define	RES_DEBUG	0x0002		/* print debug messages */
#define	RES_AAONLY	0x0004		/* authoritative answers only */
#define	RES_USEVC	0x0008		/* use virtual circuit */
#define	RES_PRIMARY	0x0010		/* query primary server only */
#define	RES_IGNTC	0x0020		/* ignore trucation errors */
#define	RES_RECURSE	0x0040		/* recursion desired */
#define	RES_DEFNAMES	0x0080		/* use default domain name */
#define	RES_STAYOPEN	0x0100		/* Keep TCP socket open */
#define	RES_DNSRCH	0x0200		/* search up local domain tree */

#define	RES_DEFAULT	(RES_RECURSE | RES_DEFNAMES | RES_DNSRCH)

extern struct state _res;

#ifdef __STDC__
extern char *p_cdname(char *, char *, FILE *);
extern char *p_rr(char *, char *, FILE *);
extern char *p_type(int);
extern char *p_class(int);
extern char *p_time(unsigned long);
#else
extern char *p_cdname(), *p_rr(), *p_type(), *p_class(), *p_time();
#endif	/* __STDC__ */

#ifdef	__cplusplus
}
#endif

#endif	/* _RESOLV_H */