xref: /aosp_15_r20/external/dnsmasq/src/nameser.h (revision c2c26c8b25cb2c9c4fe49a734c2305a522f5635e)

/*	$OpenBSD: nameser.h,v 1.11 2005/12/20 02:06:56 millert Exp $	*/

/*
 * ++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. 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
 *	$From: nameser.h,v 8.11 1996/10/08 04:51:02 vixie Exp $
 */

#ifndef _NAMESER_H_
#define _NAMESER_H_

#include <sys/cdefs.h>
#include <sys/param.h>

/*
 * 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
 */
#define PACKETSZ 512  /* maximum packet size */
#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 */

/*
 * 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
 */
#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 */

/*
 * 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 */
#define T_KX 36       /* Key Exchanger */
#define T_CERT 37     /* CERT */
#define T_A6 38       /* A6 */
#define T_DNAME 39    /* DNAME */
#define T_SINK 40     /* SINK */
#define T_OPT 41      /* OPT pseudo-RR, RFC2671 */
#define T_APL 42      /* APL */
#define T_DS 43       /* Delegation Signer */
#define T_SSHFP 44    /* SSH Key Fingerprint */
#define T_RRSIG 46    /* RRSIG */
#define T_NSEC 47     /* NSEC */
#define T_DNSKEY 48   /* DNSKEY */
                      /* 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_TKEY 249    /* Transaction Key */
#define T_TSIG 250    /* Transaction Signature */
#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)

/*
 * EDNS0 Z-field extended flags
 */
#define DNS_MESSAGEEXTFLAG_DO 0x8000U

/*
 * 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)

#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(const unsigned char*);
extern u_int32_t _getlong(const unsigned 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)                                           \
    {                                                             \
        unsigned char* t_cp = (unsigned char*) (cp);              \
        (s) = ((u_int16_t) t_cp[0] << 8) | ((u_int16_t) t_cp[1]); \
        (cp) += INT16SZ;                                          \
    }

#define GETLONG(l, cp)                                                    \
    {                                                                     \
        unsigned char* t_cp = (unsigned 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)                              \
    {                                                \
        u_int16_t t_s = (u_int16_t)(s);              \
        unsigned char* t_cp = (unsigned char*) (cp); \
        *t_cp++ = t_s >> 8;                          \
        *t_cp = t_s;                                 \
        (cp) += INT16SZ;                             \
    }

#define PUTLONG(l, cp)                               \
    {                                                \
        u_int32_t t_l = (u_int32_t)(l);              \
        unsigned char* t_cp = (unsigned 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_ */