xref: /freebsd/contrib/tcpdump/nameser.h (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*
2  * Copyright (c) 1983, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *      @(#)nameser.h	8.2 (Berkeley) 2/16/94
34  * -
35  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
36  *
37  * Permission to use, copy, modify, and distribute this software for any
38  * purpose with or without fee is hereby granted, provided that the above
39  * copyright notice and this permission notice appear in all copies, and that
40  * the name of Digital Equipment Corporation not be used in advertising or
41  * publicity pertaining to distribution of the document or software without
42  * specific, written prior permission.
43  *
44  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
45  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
46  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
47  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
48  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
49  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
50  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51  * SOFTWARE.
52  * -
53  * --Copyright--
54  */
55 
56 #ifndef _NAMESER_H_
57 #define	_NAMESER_H_
58 
59 #include <sys/types.h>
60 
61 /*
62  * Define constants based on rfc883
63  */
64 #define PACKETSZ	512		/* maximum packet size */
65 #define MAXDNAME	256		/* maximum domain name */
66 #define MAXCDNAME	255		/* maximum compressed domain name */
67 #define MAXLABEL	63		/* maximum length of domain label */
68 	/* Number of bytes of fixed size data in query structure */
69 #define QFIXEDSZ	4
70 	/* number of bytes of fixed size data in resource record */
71 #define RRFIXEDSZ	10
72 
73 /*
74  * Internet nameserver port number
75  */
76 #define NAMESERVER_PORT	53
77 
78 /*
79  * Port for multicast DNS; see
80  *
81  *	http://files.multicastdns.org/draft-cheshire-dnsext-multicastdns.txt
82  *
83  * for the current mDNS spec.
84  */
85 #define MULTICASTDNS_PORT	5353
86 
87 /*
88  * Currently defined opcodes
89  */
90 #define QUERY		0x0		/* standard query */
91 #define IQUERY		0x1		/* inverse query */
92 #define STATUS		0x2		/* nameserver status query */
93 #if 0
94 #define xxx		0x3		/* 0x3 reserved */
95 #endif
96 	/* non standard - supports ALLOW_UPDATES stuff from Mike Schwartz */
97 #define UPDATEA		0x9		/* add resource record */
98 #define UPDATED		0xa		/* delete a specific resource record */
99 #define UPDATEDA	0xb		/* delete all named resource record */
100 #define UPDATEM		0xc		/* modify a specific resource record */
101 #define UPDATEMA	0xd		/* modify all named resource record */
102 
103 #define ZONEINIT	0xe		/* initial zone transfer */
104 #define ZONEREF		0xf		/* incremental zone referesh */
105 
106 /*
107  * Undefine various #defines from various System V-flavored OSes (Solaris,
108  * SINIX, HP-UX) so the compiler doesn't whine that we redefine them.
109  */
110 #ifdef T_NULL
111 #undef T_NULL
112 #endif
113 #ifdef T_OPT
114 #undef T_OPT
115 #endif
116 #ifdef T_UNSPEC
117 #undef T_UNSPEC
118 #endif
119 #ifdef NOERROR
120 #undef NOERROR
121 #endif
122 
123 /*
124  * Currently defined response codes
125  */
126 #define NOERROR		0		/* no error */
127 #define FORMERR		1		/* format error */
128 #define SERVFAIL	2		/* server failure */
129 #define NXDOMAIN	3		/* non existent domain */
130 #define NOTIMP		4		/* not implemented */
131 #define REFUSED		5		/* query refused */
132 	/* non standard */
133 #define NOCHANGE	0xf		/* update failed to change db */
134 
135 /*
136  * Type values for resources and queries
137  */
138 #define T_A		1		/* host address */
139 #define T_NS		2		/* authoritative server */
140 #define T_MD		3		/* mail destination */
141 #define T_MF		4		/* mail forwarder */
142 #define T_CNAME		5		/* connonical name */
143 #define T_SOA		6		/* start of authority zone */
144 #define T_MB		7		/* mailbox domain name */
145 #define T_MG		8		/* mail group member */
146 #define T_MR		9		/* mail rename name */
147 #define T_NULL		10		/* null resource record */
148 #define T_WKS		11		/* well known service */
149 #define T_PTR		12		/* domain name pointer */
150 #define T_HINFO		13		/* host information */
151 #define T_MINFO		14		/* mailbox information */
152 #define T_MX		15		/* mail routing information */
153 #define T_TXT		16		/* text strings */
154 #define	T_RP		17		/* responsible person */
155 #define	T_AFSDB		18		/* AFS cell database */
156 #define T_X25		19		/* X_25 calling address */
157 #define T_ISDN		20		/* ISDN calling address */
158 #define T_RT		21		/* router */
159 #define	T_NSAP		22		/* NSAP address */
160 #define	T_NSAP_PTR	23		/* reverse lookup for NSAP */
161 #define T_SIG		24		/* security signature */
162 #define T_KEY		25		/* security key */
163 #define T_PX		26		/* X.400 mail mapping */
164 #define T_GPOS		27		/* geographical position (withdrawn) */
165 #define T_AAAA		28		/* IP6 Address */
166 #define T_LOC		29		/* Location Information */
167 #define T_NXT		30		/* Next Valid Name in Zone */
168 #define T_EID		31		/* Endpoint identifier */
169 #define T_NIMLOC	32		/* Nimrod locator */
170 #define T_SRV		33		/* Server selection */
171 #define T_ATMA		34		/* ATM Address */
172 #define T_NAPTR		35		/* Naming Authority PoinTeR */
173 #define T_KX		36		/* Key Exchanger */
174 #define T_CERT		37		/* Certificates in the DNS */
175 #define T_A6		38		/* IP6 address */
176 #define T_DNAME		39		/* non-terminal redirection */
177 #define T_SINK		40		/* unknown */
178 #define T_OPT		41		/* EDNS0 option (meta-RR) */
179 #define T_APL		42		/* lists of address prefixes */
180 #define T_DS		43		/* Delegation Signer */
181 #define T_SSHFP		44		/* SSH Fingerprint */
182 #define T_IPSECKEY	45		/* IPsec keying material */
183 #define T_RRSIG		46		/* new security signature */
184 #define T_NSEC		47		/* provable insecure information */
185 #define T_DNSKEY	48		/* new security key */
186 	/* non standard */
187 #define T_SPF		99		/* sender policy framework */
188 #define T_UINFO		100		/* user (finger) information */
189 #define T_UID		101		/* user ID */
190 #define T_GID		102		/* group ID */
191 #define T_UNSPEC	103		/* Unspecified format (binary data) */
192 #define T_UNSPECA	104		/* "unspecified ascii". Ugly MIT hack */
193 	/* Query type values which do not appear in resource records */
194 #define T_TKEY		249		/* Transaction Key [RFC2930] */
195 #define T_TSIG		250		/* Transaction Signature [RFC2845] */
196 #define T_IXFR		251		/* incremental transfer [RFC1995] */
197 #define T_AXFR		252		/* transfer zone of authority */
198 #define T_MAILB		253		/* transfer mailbox records */
199 #define T_MAILA		254		/* transfer mail agent records */
200 #define T_ANY		255		/* wildcard match */
201 
202 /*
203  * Values for class field
204  */
205 
206 #define C_IN		1		/* the arpa internet */
207 #define C_CHAOS		3		/* for chaos net (MIT) */
208 #define C_HS		4		/* for Hesiod name server (MIT) (XXX) */
209 	/* Query class values which do not appear in resource records */
210 #define C_ANY		255		/* wildcard match */
211 #define C_QU		0x8000		/* mDNS QU flag in queries */
212 #define C_CACHE_FLUSH	0x8000		/* mDNS cache flush flag in replies */
213 
214 /*
215  * Status return codes for T_UNSPEC conversion routines
216  */
217 #define CONV_SUCCESS 0
218 #define CONV_OVERFLOW -1
219 #define CONV_BADFMT -2
220 #define CONV_BADCKSUM -3
221 #define CONV_BADBUFLEN -4
222 
223 /*
224  * Structure for query header.
225  */
226 typedef struct {
227 	uint16_t id;		/* query identification number */
228 	uint8_t  flags1;	/* first byte of flags */
229 	uint8_t  flags2;	/* second byte of flags */
230 	uint16_t qdcount;	/* number of question entries */
231 	uint16_t ancount;	/* number of answer entries */
232 	uint16_t nscount;	/* number of authority entries */
233 	uint16_t arcount;	/* number of resource entries */
234 } HEADER;
235 
236 /*
237  * Macros for subfields of flag fields.
238  */
239 #define DNS_QR(np)	((np)->flags1 & 0x80)		/* response flag */
240 #define DNS_OPCODE(np)	((((np)->flags1) >> 3) & 0xF)	/* purpose of message */
241 #define DNS_AA(np)	((np)->flags1 & 0x04)		/* authoritative answer */
242 #define DNS_TC(np)	((np)->flags1 & 0x02)		/* truncated message */
243 #define DNS_RD(np)	((np)->flags1 & 0x01)		/* recursion desired */
244 
245 #define DNS_RA(np)	((np)->flags2 & 0x80)	/* recursion available */
246 #define DNS_AD(np)	((np)->flags2 & 0x20)	/* authentic data from named */
247 #define DNS_CD(np)	((np)->flags2 & 0x10)	/* checking disabled by resolver */
248 #define DNS_RCODE(np)	((np)->flags2 & 0xF)	/* response code */
249 
250 /*
251  * Defines for handling compressed domain names, EDNS0 labels, etc.
252  */
253 #define INDIR_MASK	0xc0	/* 11.... */
254 #define EDNS0_MASK	0x40	/* 01.... */
255 #  define EDNS0_ELT_BITLABEL 0x01
256 
257 /*
258  * Structure for passing resource records around.
259  */
260 struct rrec {
261 	int16_t	r_zone;			/* zone number */
262 	int16_t	r_class;		/* class number */
263 	int16_t	r_type;			/* type number */
264 	uint32_t	r_ttl;			/* time to live */
265 	int	r_size;			/* size of data area */
266 	char	*r_data;		/* pointer to data */
267 };
268 
269 /*
270  * Inline versions of get/put short/long.  Pointer is advanced.
271  * We also assume that a "uint16_t" holds 2 "chars"
272  * and that a "uint32_t" holds 4 "chars".
273  *
274  * These macros demonstrate the property of C whereby it can be
275  * portable or it can be elegant but never both.
276  */
277 #define GETSHORT(s, cp) { \
278 	register u_char *t_cp = (u_char *)(cp); \
279 	(s) = ((uint16_t)t_cp[0] << 8) | (uint16_t)t_cp[1]; \
280 	(cp) += 2; \
281 }
282 
283 #define GETLONG(l, cp) { \
284 	register u_char *t_cp = (u_char *)(cp); \
285 	(l) = (((uint32_t)t_cp[0]) << 24) \
286 	    | (((uint32_t)t_cp[1]) << 16) \
287 	    | (((uint32_t)t_cp[2]) << 8) \
288 	    | (((uint32_t)t_cp[3])); \
289 	(cp) += 4; \
290 }
291 
292 #define PUTSHORT(s, cp) { \
293 	register uint16_t t_s = (uint16_t)(s); \
294 	register u_char *t_cp = (u_char *)(cp); \
295 	*t_cp++ = t_s >> 8; \
296 	*t_cp   = t_s; \
297 	(cp) += 2; \
298 }
299 
300 /*
301  * Warning: PUTLONG --no-longer-- destroys its first argument.  if you
302  * were depending on this "feature", you will lose.
303  */
304 #define PUTLONG(l, cp) { \
305 	register uint32_t t_l = (uint32_t)(l); \
306 	register u_char *t_cp = (u_char *)(cp); \
307 	*t_cp++ = t_l >> 24; \
308 	*t_cp++ = t_l >> 16; \
309 	*t_cp++ = t_l >> 8; \
310 	*t_cp   = t_l; \
311 	(cp) += 4; \
312 }
313 
314 #endif /* !_NAMESER_H_ */
315