/*
 * ++Copyright++ 1983, 1989, 1993
 * -
 * Copyright (c) 1983, 1989, 1993
 *    The Regents of the University of California.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 * 	This product includes software developed by the University of
 * 	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * -
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 * 
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 * -
 * Portions Copyright (c) 1995 by International Business Machines, Inc.
 *
 * International Business Machines, Inc. (hereinafter called IBM) grants
 * permission under its copyrights to use, copy, modify, and distribute this
 * Software with or without fee, provided that the above copyright notice and
 * all paragraphs of this notice appear in all copies, and that the name of IBM
 * not be used in connection with the marketing of any product incorporating
 * the Software or modifications thereof, without specific, written prior
 * permission.
 *
 * To the extent it has a right to do so, IBM grants an immunity from suit
 * under its patents, if any, for the use, sale or manufacture of products to
 * the extent that such products are used for performing Domain Name System
 * dynamic updates in TCP/IP networks by means of the Software.  No immunity is
 * granted for any product per se or for any other function of any product.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE.  IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL,
 * DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN
 * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * --Copyright--
 */

/*
 *      @(#)nameser.h	8.1 (Berkeley) 6/2/93
 *	$Id: nameser.h,v 8.11 1996/10/08 04:51:02 vixie Exp $
 */

#ifndef _NAMESER_H_
#define _NAMESER_H_

#ifndef WINNT
#include <sys/param.h>
#endif
#if (!defined(BSD)) || (BSD < 199306)
# include <sys/bitypes.h>
#else
# include <sys/types.h>
#endif
#include <sys/cdefs.h>

#ifdef _AUX_SOURCE
# include <sys/types.h>
#endif

/*
 * revision information.  this is the release date in YYYYMMDD format.
 * it can change every day so the right thing to do with it is use it
 * in preprocessor commands such as "#if (__BIND > 19931104)".  do not
 * compare for equality; rather, use it to determine whether your resolver
 * is new enough to contain a certain feature.
 */

#define __BIND		19960801	/* interface version stamp */

/*
 * Define constants based on rfc883
 */
/* START MODIFICATION by CNRG/ITX  03/03/99 */
#define PACKETSZ	/*512*/16384		/* maximum packet size */
/* END MODIFICATION by CNRG/ITX  03/03/99 */
#define MAXDNAME	1025	/* maximum presentation domain name */
#define MAXCDNAME	255		/* maximum compressed domain name */
#define MAXLABEL	63		/* maximum length of domain label */
#define HFIXEDSZ	12		/* #/bytes of fixed data in header */
#define QFIXEDSZ	4		/* #/bytes of fixed data in query */
#define RRFIXEDSZ	10		/* #/bytes of fixed data in r record */
#define INT32SZ		4		/* for systems without 32-bit ints */
#define INT16SZ		2		/* for systems without 16-bit ints */
#define INADDRSZ	4		/* IPv4 T_A */
#define IN6ADDRSZ	16		/* IPv6 T_AAAA */


/* START MODIFICATION by CNRG/ITX  03/03/99 */
/*
 * Currently defined opcodes.
 */
typedef enum __ns_opcode {
	ns_o_query = 0,		/* Standard query. */
	ns_o_iquery = 1,	/* Inverse query (deprecated/unsupported). */
	ns_o_status = 2,	/* Name server status query (unsupported). */
				/* Opcode 3 is undefined/reserved. */
	ns_o_notify = 4,	/* Zone change notification. */
	ns_o_update = 5,	/* Zone update message. */
	ns_o_max = 6
} ns_opcode;


#ifdef DSCOMM_EXPORTS
					
#define C_NONE		ns_c_none
#define S_ZONE		ns_s_zn
#define S_PREREQ	ns_s_pr
#define YXDOMAIN	ns_r_yxdomain
#define YXRRSET		ns_r_yxrrset
#define NXRRSET		ns_r_nxrrset

/*
 * Currently defined response codes.
 */
typedef	enum __ns_rcode {
	ns_r_noerror = 0,	/* No error occurred. */
	ns_r_formerr = 1,	/* Format error. */
	ns_r_servfail = 2,	/* Server failure. */
	ns_r_nxdomain = 3,	/* Name error. */
	ns_r_notimpl = 4,	/* Unimplemented. */
	ns_r_refused = 5,	/* Operation refused. */
	/* these are for BIND_UPDATE */
	ns_r_yxdomain = 6,	/* Name exists */
	ns_r_yxrrset = 7,	/* RRset exists */
	ns_r_nxrrset = 8,	/* RRset does not exist */
	ns_r_notauth = 9,	/* Not authoritative for zone */
	ns_r_notzone = 10,	/* Zone of record different from zone section */
	ns_r_max = 11
} ns_rcode;

/* BIND_UPDATE */
typedef enum __ns_update_operation {
	ns_uop_delete = 0,
	ns_uop_add = 1,
	ns_uop_max = 2
} ns_update_operation;

/*
 * This RR-like structure is particular to UPDATE.
 */
struct ns_updrec {
	struct ns_updrec *r_prev;	/* prev record */
	struct ns_updrec *r_next;	/* next record */
	u_int8_t	r_section;	/* ZONE/PREREQUISITE/UPDATE */
	char *		r_dname;	/* owner of the RR */
	u_int16_t	r_class;	/* class number */
	u_int16_t	r_type;		/* type number */
	u_int32_t	r_ttl;		/* time to live */
	u_char *	r_data;		/* rdata fields as text string */
	u_int16_t	r_size;		/* size of r_data field */
	int		r_opcode;	/* type of operation */
	/* following fields for private use by the resolver/server routines */
	struct ns_updrec *r_grpnext;	/* next record when grouped */
	struct databuf *r_dp;		/* databuf to process */
	struct databuf *r_deldp;	/* databuf's deleted/overwritten */
	u_int16_t	r_zone;		/* zone number on server */
};
typedef struct ns_updrec ns_updrec;

/*
 * Currently defined type values for resources and queries.
 */
typedef enum __ns_type {
	ns_t_a = 1,		/* Host address. */
	ns_t_ns = 2,		/* Authoritative server. */
	ns_t_md = 3,		/* Mail destination. */
	ns_t_mf = 4,		/* Mail forwarder. */
	ns_t_cname = 5,		/* Canonical name. */
	ns_t_soa = 6,		/* Start of authority zone. */
	ns_t_mb = 7,		/* Mailbox domain name. */
	ns_t_mg = 8,		/* Mail group member. */
	ns_t_mr = 9,		/* Mail rename name. */
	ns_t_null = 10,		/* Null resource record. */
	ns_t_wks = 11,		/* Well known service. */
	ns_t_ptr = 12,		/* Domain name pointer. */
	ns_t_hinfo = 13,	/* Host information. */
	ns_t_minfo = 14,	/* Mailbox information. */
	ns_t_mx = 15,		/* Mail routing information. */
	ns_t_txt = 16,		/* Text strings. */
	ns_t_rp = 17,		/* Responsible person. */
	ns_t_afsdb = 18,	/* AFS cell database. */
	ns_t_x25 = 19,		/* X_25 calling address. */
	ns_t_isdn = 20,		/* ISDN calling address. */
	ns_t_rt = 21,		/* Router. */
	ns_t_nsap = 22,		/* NSAP address. */
	ns_t_nsap_ptr = 23,	/* Reverse NSAP lookup (deprecated). */
	ns_t_sig = 24,		/* Security signature. */
	ns_t_key = 25,		/* Security key. */
	ns_t_px = 26,		/* X.400 mail mapping. */
	ns_t_gpos = 27,		/* Geographical position (withdrawn). */
	ns_t_aaaa = 28,		/* Ip6 Address. */
	ns_t_loc = 29,		/* Location Information. */
	ns_t_nxt = 30,		/* Next domain (security). */
	ns_t_eid = 31,		/* Endpoint identifier. */
	ns_t_nimloc = 32,	/* Nimrod Locator. */
	ns_t_srv = 33,		/* Server Selection. */
	ns_t_atma = 34,		/* ATM Address */
	ns_t_naptr = 35,	/* Naming Authority PoinTeR */
	/* Query type values which do not appear in resource records. */
	ns_t_ixfr = 251,	/* Incremental zone transfer. */
	ns_t_axfr = 252,	/* Transfer zone of authority. */
	ns_t_mailb = 253,	/* Transfer mailbox records. */
	ns_t_maila = 254,	/* Transfer mail agent records. */
	ns_t_any = 255,		/* Wildcard match. */
	ns_t_max = 65536
} ns_type;

/*
 * Values for class field
 */
typedef enum __ns_class {
	ns_c_in = 1,		/* Internet. */
				/* Class 2 unallocated/unsupported. */
	ns_c_chaos = 3,		/* MIT Chaos-net. */
	ns_c_hs = 4,		/* MIT Hesiod. */
	/* Query class values which do not appear in resource records */
	ns_c_none = 254,	/* for prereq. sections in update requests */
	ns_c_any = 255,		/* Wildcard match. */
	ns_c_max = 65536
} ns_class;

/*
 * These can be expanded with synonyms, just keep ns_parse.c:ns_parserecord()
 * in synch with it.
 */
typedef enum __ns_sect {
	ns_s_qd = 0,		/* Query: Question. */
	ns_s_zn = 0,		/* Update: Zone. */
	ns_s_an = 1,		/* Query: Answer. */
	ns_s_pr = 1,		/* Update: Prerequisites. */
	ns_s_ns = 2,		/* Query: Name servers. */
	ns_s_ud = 2,		/* Update: Update. */
	ns_s_ar = 3,		/* Query|Update: Additional records. */
	ns_s_max = 4
} ns_sect;

/*
 * This is a message handle.  It is caller allocated and has no dynamic data.
 * This structure is intended to be opaque to all but ns_parse.c, thus the
 * leading _'s on the member names.  Use the accessor functions, not the _'s.
 */
typedef struct __ns_msg {
	const u_char	*_msg;
	const u_char    *_eom;
	u_int16_t	_id, _flags, _counts[ns_s_max];
	const u_char	*_sections[ns_s_max];
	ns_sect		_sect;
	int		_rrnum;
	const u_char	*_ptr;
} ns_msg;


/* Accessor macros - this is part of the public interface. */
#define ns_msg_count(handle, section) ((handle)._counts[section] + 0)

/*
 * This is a parsed record.  It is caller allocated and has no dynamic data.
 */
typedef	struct __ns_rr {
	char		name[MAXDNAME];	/* XXX need to malloc */
	u_int16_t	type;
	u_int16_t	nclass;			// change class to nclass
	u_int32_t	ttl;
	u_int16_t	rdlength;
	const u_char	*rdata;
} ns_rr;

/* Accessor macros - this is part of the public interface. */
#define ns_rr_name(rr)	(((rr).name[0] != '\0') ? (rr).name : ".")
#define ns_rr_type(rr)	((rr).type + 0)
#define ns_rr_class(rr)	((rr).nclass + 0)
#define ns_rr_ttl(rr)	((rr).ttl + 0)
#define ns_rr_rdlen(rr)	((rr).rdlength + 0)
#define ns_rr_rdata(rr)	((rr).rdata + 0)

#endif
/* START MODIFICATION by CNRG/ITX  03/03/99 */


/*
 * 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 */
#define NS_NOTIFY_OP	0x4		/* notify secondary of SOA change */
/*
 * Currently defined response codes
 */
#if !(defined(WINNT) && defined(NOERROR))
#define NOERROR		0		/* no error */
#endif
#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 */

/*
 * 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		/* canonical 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 */
#define T_RP		17		/* responsible person */
#define T_AFSDB		18		/* AFS cell database */
#define T_X25		19		/* X_25 calling address */
#define T_ISDN		20		/* ISDN calling address */
#define T_RT		21		/* router */
#define T_NSAP		22		/* NSAP address */
#define T_NSAP_PTR	23		/* reverse NSAP lookup (deprecated) */
#define T_SIG		24		/* security signature */
#define T_KEY		25		/* security key */
#define T_PX		26		/* X.400 mail mapping */
#define T_GPOS		27		/* geographical position (withdrawn) */
#define T_AAAA		28		/* IP6 Address */
#define T_LOC		29		/* Location Information */
#define T_NXT		30		/* Next Valid Name in Zone */
#define T_EID		31		/* Endpoint identifier */
#define T_NIMLOC	32		/* Nimrod locator */
#define T_SRV		33		/* Server selection */
#define T_ATMA		34		/* ATM Address */
#define T_NAPTR		35		/* Naming Authority PoinTeR */
	/* 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_IXFR		251		/* incremental zone transfer */
#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 (MIT) */
#define C_HS		4		/* for Hesiod name server (MIT) (XXX) */
	/* Query class values which do not appear in resource records */
#define C_ANY		255		/* wildcard match */

/*
 * Flags field of the KEY RR rdata
 */
#define	KEYFLAG_TYPEMASK	0xC000	/* Mask for "type" bits */
#define	KEYFLAG_TYPE_AUTH_CONF	0x0000	/* Key usable for both */
#define	KEYFLAG_TYPE_CONF_ONLY	0x8000	/* Key usable for confidentiality */
#define	KEYFLAG_TYPE_AUTH_ONLY	0x4000	/* Key usable for authentication */
#define	KEYFLAG_TYPE_NO_KEY	0xC000	/* No key usable for either; no key */
/* The type bits can also be interpreted independently, as single bits: */
#define	KEYFLAG_NO_AUTH		0x8000	/* Key not usable for authentication */
#define	KEYFLAG_NO_CONF		0x4000	/* Key not usable for confidentiality */

#define	KEYFLAG_EXPERIMENTAL	0x2000	/* Security is *mandatory* if bit=0 */
#define	KEYFLAG_RESERVED3	0x1000  /* reserved - must be zero */
#define	KEYFLAG_RESERVED4	0x0800  /* reserved - must be zero */
#define	KEYFLAG_USERACCOUNT	0x0400	/* key is assoc. with a user acct */
#define	KEYFLAG_ENTITY		0x0200	/* key is assoc. with entity eg host */
#define	KEYFLAG_ZONEKEY		0x0100	/* key is zone key for the zone named */
#define	KEYFLAG_IPSEC		0x0080  /* key is for IPSEC use (host or user)*/
#define	KEYFLAG_EMAIL		0x0040  /* key is for email (MIME security) */
#define	KEYFLAG_RESERVED10	0x0020  /* reserved - must be zero */
#define	KEYFLAG_RESERVED11	0x0010  /* reserved - must be zero */
#define	KEYFLAG_SIGNATORYMASK	0x000F	/* key can sign DNS RR's of same name */

#define  KEYFLAG_RESERVED_BITMASK ( KEYFLAG_RESERVED3 | \
				    KEYFLAG_RESERVED4 | \
				    KEYFLAG_RESERVED10| KEYFLAG_RESERVED11) 

/* The Algorithm field of the KEY and SIG RR's is an integer, {1..254} */
#define	ALGORITHM_MD5RSA	1	/* MD5 with RSA */
#define	ALGORITHM_EXPIRE_ONLY	253	/* No alg, no security */
#define	ALGORITHM_PRIVATE_OID	254	/* Key begins with OID indicating alg */

/* Signatures */
					/* Size of a mod or exp in bits */
#define	MIN_MD5RSA_KEY_PART_BITS	 512
#define	MAX_MD5RSA_KEY_PART_BITS	2552
					/* Total of binary mod and exp, bytes */
#define	MAX_MD5RSA_KEY_BYTES		((MAX_MD5RSA_KEY_PART_BITS+7/8)*2+3)
					/* Max length of text sig block */
#define	MAX_KEY_BASE64			(((MAX_MD5RSA_KEY_BYTES+2)/3)*4)

/*
 * 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)

#ifndef BYTE_ORDER
#if (BSD >= 199103)
# include <machine/endian.h>
#else
#ifdef linux
# include <endian.h>
#else
#define LITTLE_ENDIAN	1234	/* least-significant byte first (vax, pc) */
#define BIG_ENDIAN	4321	/* most-significant byte first (IBM, net) */
#define PDP_ENDIAN	3412	/* LSB first in word, MSW first in long (pdp)*/

#if defined(vax) || defined(ns32000) || defined(sun386) || defined(i386) || \
    defined(MIPSEL) || defined(_MIPSEL) || defined(BIT_ZERO_ON_RIGHT) || \
    defined(__alpha__) || defined(__alpha)
#define BYTE_ORDER	LITTLE_ENDIAN
#endif

#if defined(sel) || defined(pyr) || defined(mc68000) || defined(sparc) || \
    defined(is68k) || defined(tahoe) || defined(ibm032) || defined(ibm370) || \
    defined(MIPSEB) || defined(_MIPSEB) || defined(_IBMR2) || defined(DGUX) ||\
    defined(apollo) || defined(__convex__) || defined(_CRAY) || \
    defined(__hppa) || defined(__hp9000) || \
    defined(__hp9000s300) || defined(__hp9000s700) || \
    defined (BIT_ZERO_ON_LEFT) || defined(m68k)
#define BYTE_ORDER	BIG_ENDIAN
#endif
#endif /* linux */
#endif /* BSD */
#endif /* BYTE_ORDER */

#if !defined(BYTE_ORDER) || \
    (BYTE_ORDER != BIG_ENDIAN && BYTE_ORDER != LITTLE_ENDIAN && \
    BYTE_ORDER != PDP_ENDIAN)
	/* you must determine what the correct bit order is for
	 * your compiler - the next line is an intentional error
	 * which will force your compiles to bomb until you fix
	 * the above macros.
	 */
  error "Undefined or invalid BYTE_ORDER";
#endif

/*
 * Structure for query header.  The order of the fields is machine- and
 * compiler-dependent, depending on the byte/bit order and the layout
 * of bit fields.  We use bit fields only in int variables, as this
 * is all ANSI requires.  This requires a somewhat confusing rearrangement.
 */

typedef struct {
	unsigned	id :16;		/* query identification number */
#if BYTE_ORDER == BIG_ENDIAN
			/* fields in third byte */
	unsigned	qr: 1;		/* response flag */
	unsigned	opcode: 4;	/* purpose of message */
	unsigned	aa: 1;		/* authoritive answer */
	unsigned	tc: 1;		/* truncated message */
	unsigned	rd: 1;		/* recursion desired */
			/* fields in fourth byte */
	unsigned	ra: 1;		/* recursion available */
	unsigned	unused :1;	/* unused bits (MBZ as of 4.9.3a3) */
	unsigned	ad: 1;		/* authentic data from named */
	unsigned	cd: 1;		/* checking disabled by resolver */
	unsigned	rcode :4;	/* response code */
#endif
#if BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
			/* fields in third byte */
	unsigned	rd :1;		/* recursion desired */
	unsigned	tc :1;		/* truncated message */
	unsigned	aa :1;		/* authoritive answer */
	unsigned	opcode :4;	/* purpose of message */
	unsigned	qr :1;		/* response flag */
			/* fields in fourth byte */
	unsigned	rcode :4;	/* response code */
	unsigned	cd: 1;		/* checking disabled by resolver */
	unsigned	ad: 1;		/* authentic data from named */
	unsigned	unused :1;	/* unused bits (MBZ as of 4.9.3a3) */
	unsigned	ra :1;		/* recursion available */
#endif
			/* remaining bytes */
	unsigned	qdcount :16;	/* number of question entries */
	unsigned	ancount :16;	/* number of answer entries */
	unsigned	nscount :16;	/* number of authority entries */
	unsigned	arcount :16;	/* number of resource entries */
} HEADER;

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

extern	u_int16_t	_getshort __P((const u_char *));
extern	u_int32_t	_getlong __P((const u_char *));

/*
 * Inline versions of get/put short/long.  Pointer is advanced.
 *
 * These macros demonstrate the property of C whereby it can be
 * portable or it can be elegant but rarely both.
 */
#define GETSHORT(s, cp) { \
	register u_char *t_cp = (u_char *)(cp); \
	(s) = ((u_int16_t)t_cp[0] << 8) \
	    | ((u_int16_t)t_cp[1]) \
	    ; \
	(cp) += INT16SZ; \
}

#define GETLONG(l, cp) { \
	register u_char *t_cp = (u_char *)(cp); \
	(l) = ((u_int32_t)t_cp[0] << 24) \
	    | ((u_int32_t)t_cp[1] << 16) \
	    | ((u_int32_t)t_cp[2] << 8) \
	    | ((u_int32_t)t_cp[3]) \
	    ; \
	(cp) += INT32SZ; \
}

#define PUTSHORT(s, cp) { \
	register u_int16_t t_s = (u_int16_t)(s); \
	register u_char *t_cp = (u_char *)(cp); \
	*t_cp++ = (char) (t_s >> 8); \
	*t_cp   = (char) t_s; \
	(cp) += INT16SZ; \
}

#define PUTLONG(l, cp) { \
	register u_int32_t t_l = (u_int32_t)(l); \
	register u_char *t_cp = (u_char *)(cp); \
	*t_cp++ = t_l >> 24; \
	*t_cp++ = t_l >> 16; \
	*t_cp++ = t_l >> 8; \
	*t_cp   = t_l; \
	(cp) += INT32SZ; \
}

#endif /* !_NAMESER_H_ */
