REDROOM

Navigation

Breadcrumbs

/ / usr / include / bind9 / dns

Create

Create File | Create Folder | Upload Files | Run Command

Preview: compress.h Size: 6.49 KB

//usr/include/bind9/dns/compress.h

/*
 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
 *
 * See the COPYRIGHT file distributed with this work for additional
 * information regarding copyright ownership.
 */

#ifndef DNS_COMPRESS_H
#define DNS_COMPRESS_H 1

#include <inttypes.h>
#include <stdbool.h>

#include <isc/lang.h>
#include <isc/region.h>

#include <dns/types.h>

ISC_LANG_BEGINDECLS

/*! \file dns/compress.h
 * Direct manipulation of the structures is strongly discouraged.
 *
 * A name compression context handles compression of multiple DNS names
 * in relation to a single DNS message. The context can be used to
 * selectively turn on/off compression for specific names (depending on
 * the RR type) by using \c dns_compress_setmethods(). Alternately,
 * compression can be disabled completely using \c
 * dns_compress_disable().
 *
 * \c dns_compress_setmethods() is intended for use by RDATA towire()
 * implementations, whereas \c dns_compress_disable() is intended to be
 * used by a nameserver's configuration manager.
 */

#define DNS_COMPRESS_NONE		0x00	/*%< no compression */
#define DNS_COMPRESS_GLOBAL14		0x01	/*%< "normal" compression. */
#define DNS_COMPRESS_ALL		0x01	/*%< all compression. */
#define DNS_COMPRESS_CASESENSITIVE	0x02	/*%< case sensitive compression. */
#define DNS_COMPRESS_ENABLED		0x04

#define DNS_COMPRESS_READY		0x80000000

#define DNS_COMPRESS_TABLESIZE 64
#define DNS_COMPRESS_INITIALNODES 16

typedef struct dns_compressnode dns_compressnode_t;

struct dns_compressnode {
	isc_region_t		r;
	uint16_t		offset;
	uint16_t		count;
	uint8_t			labels;
	dns_compressnode_t	*next;
};

struct dns_compress {
	unsigned int		magic;		/*%< Magic number. */
	unsigned int		allowed;	/*%< Allowed methods. */
	int			edns;		/*%< Edns version or -1. */
	/*% Global compression table. */
	dns_compressnode_t	*table[DNS_COMPRESS_TABLESIZE];
	/*% Preallocated nodes for the table. */
	dns_compressnode_t	initialnodes[DNS_COMPRESS_INITIALNODES];
	uint16_t		count;		/*%< Number of nodes. */
	isc_mem_t		*mctx;		/*%< Memory context. */
};

typedef enum {
	DNS_DECOMPRESS_ANY,			/*%< Any compression */
	DNS_DECOMPRESS_STRICT,			/*%< Allowed compression */
	DNS_DECOMPRESS_NONE			/*%< No compression */
} dns_decompresstype_t;

struct dns_decompress {
	unsigned int		magic;		/*%< Magic number. */
	unsigned int		allowed;	/*%< Allowed methods. */
	int			edns;		/*%< Edns version or -1. */
	dns_decompresstype_t	type;		/*%< Strict checking */
};

isc_result_t
dns_compress_init(dns_compress_t *cctx, int edns, isc_mem_t *mctx);
/*%<
 *	Initialise the compression context structure pointed to by
 *	'cctx'. A freshly initialized context has name compression
 *	enabled, but no methods are set. Please use \c
 *	dns_compress_setmethods() to set a compression method.
 *
 *	Requires:
 *	\li	'cctx' is a valid dns_compress_t structure.
 *	\li	'mctx' is an initialized memory context.
 *	Ensures:
 *	\li	cctx->global is initialized.
 *
 *	Returns:
 *	\li	#ISC_R_SUCCESS
 */

void
dns_compress_invalidate(dns_compress_t *cctx);

/*%<
 *	Invalidate the compression structure pointed to by cctx.
 *
 *	Requires:
 *\li		'cctx' to be initialized.
 */

void
dns_compress_setmethods(dns_compress_t *cctx, unsigned int allowed);

/*%<
 *	Sets allowed compression methods.
 *
 *	Requires:
 *\li		'cctx' to be initialized.
 */

unsigned int
dns_compress_getmethods(dns_compress_t *cctx);

/*%<
 *	Gets allowed compression methods.
 *
 *	Requires:
 *\li		'cctx' to be initialized.
 *
 *	Returns:
 *\li		allowed compression bitmap.
 */

void
dns_compress_disable(dns_compress_t *cctx);
/*%<
 *	Disables all name compression in the context. Once disabled,
 *	name compression cannot currently be re-enabled.
 *
 *	Requires:
 *\li		'cctx' to be initialized.
 *
 */

void
dns_compress_setsensitive(dns_compress_t *cctx, bool sensitive);

/*
 *	Preserve the case of compressed domain names.
 *
 *	Requires:
 *		'cctx' to be initialized.
 */

bool
dns_compress_getsensitive(dns_compress_t *cctx);
/*
 *	Return whether case is to be preserved when compressing
 *	domain names.
 *
 *	Requires:
 *		'cctx' to be initialized.
 */

int
dns_compress_getedns(dns_compress_t *cctx);

/*%<
 *	Gets edns value.
 *
 *	Requires:
 *\li		'cctx' to be initialized.
 *
 *	Returns:
 *\li		-1 .. 255
 */

bool
dns_compress_findglobal(dns_compress_t *cctx, const dns_name_t *name,
			dns_name_t *prefix, uint16_t *offset);
/*%<
 *	Finds longest possible match of 'name' in the global compression table.
 *
 *	Requires:
 *\li		'cctx' to be initialized.
 *\li		'name' to be a absolute name.
 *\li		'prefix' to be initialized.
 *\li		'offset' to point to an uint16_t.
 *
 *	Ensures:
 *\li		'prefix' and 'offset' are valid if true is 	returned.
 *
 *	Returns:
 *\li		#true / #false
 */

void
dns_compress_add(dns_compress_t *cctx, const dns_name_t *name,
		 const dns_name_t *prefix, uint16_t offset);
/*%<
 *	Add compression pointers for 'name' to the compression table,
 *	not replacing existing pointers.
 *
 *	Requires:
 *\li		'cctx' initialized
 *
 *\li		'name' must be initialized and absolute, and must remain
 *		valid until the message compression is complete.
 *
 *\li		'prefix' must be a prefix returned by
 *		dns_compress_findglobal(), or the same as 'name'.
 */

void
dns_compress_rollback(dns_compress_t *cctx, uint16_t offset);

/*%<
 *	Remove any compression pointers from global table >= offset.
 *
 *	Requires:
 *\li		'cctx' is initialized.
 */

void
dns_decompress_init(dns_decompress_t *dctx, int edns,
		    dns_decompresstype_t type);

/*%<
 *	Initializes 'dctx'.
 *	Records 'edns' and 'type' into the structure.
 *
 *	Requires:
 *\li		'dctx' to be a valid pointer.
 */

void
dns_decompress_invalidate(dns_decompress_t *dctx);

/*%<
 *	Invalidates 'dctx'.
 *
 *	Requires:
 *\li		'dctx' to be initialized
 */

void
dns_decompress_setmethods(dns_decompress_t *dctx, unsigned int allowed);

/*%<
 *	Sets 'dctx->allowed' to 'allowed'.
 *
 *	Requires:
 *\li		'dctx' to be initialized
 */

unsigned int
dns_decompress_getmethods(dns_decompress_t *dctx);

/*%<
 *	Returns 'dctx->allowed'
 *
 *	Requires:
 *\li		'dctx' to be initialized
 */

int
dns_decompress_edns(dns_decompress_t *dctx);

/*%<
 *	Returns 'dctx->edns'
 *
 *	Requires:
 *\li		'dctx' to be initialized
 */

dns_decompresstype_t
dns_decompress_type(dns_decompress_t *dctx);

/*%<
 *	Returns 'dctx->type'
 *
 *	Requires:
 *\li		'dctx' to be initialized
 */

ISC_LANG_ENDDECLS

#endif /* DNS_COMPRESS_H */

Directory Contents

Dirs: 0 × Files: 97

Sort:

Enable drag-to-move

Name	Size	Perms	Modified	Actions
acache.h	13.90 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
acl.h	7.07 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
adb.h	22.07 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
badcache.h	3.29 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
bit.h	807 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
byaddr.h	3.91 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
cache.h	8.44 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
callbacks.h	2.22 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
catz.h	11.56 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
cert.h	1.43 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
client.h	21.53 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
clientinfo.h	1.96 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
compress.h	6.49 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
db.h	45.96 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dbiterator.h	7.25 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dbtable.h	3.09 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
diff.h	6.82 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dispatch.h	16.04 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dlz.h	10.37 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dlz_dlopen.h	4.57 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dns64.h	5.50 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dnssec.h	11.83 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dnstap.h	9.14 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
ds.h	1.20 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dsdigest.h	1.68 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
dyndb.h	4.72 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
ecdb.h	809 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
edns.h	722 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
enumclass.h	1.19 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
enumtype.h	8.11 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
events.h	3.96 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
fixedname.h	1.62 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
forward.h	3.37 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
geoip.h	2.73 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
ipkeylist.h	2.13 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
iptable.h	1.58 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
journal.h	8.03 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
keydata.h	1.03 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
keyflags.h	1.25 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
keytable.h	9.24 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
keyvalues.h	4.06 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
lib.h	1.16 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
log.h	3.87 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
lookup.h	2.86 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
master.h	11.02 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
masterdump.h	12.35 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
message.h	38.11 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
name.h	36.25 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
ncache.h	4.81 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
nsec.h	2.86 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
nsec3.h	7.84 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
nta.h	4.44 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
opcode.h	1007 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
order.h	1.95 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
peer.h	5.83 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
portlist.h	2.05 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
private.h	1.89 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rbt.h	39.67 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rcode.h	2.42 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdata.h	21.11 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdataclass.h	2.20 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdatalist.h	2.51 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdataset.h	21.03 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdatasetiter.h	3.83 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdataslab.h	4.40 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdatastruct.h	60.14 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rdatatype.h	2.24 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
request.h	10.89 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
resolver.h	19.75 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
result.h	9.07 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rootns.h	892 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rpz.h	10.09 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rriterator.h	4.13 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
rrl.h	6.48 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
sdb.h	7.05 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
sdlz.h	13.88 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
secalg.h	1.67 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
secproto.h	1.52 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
soa.h	2.13 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
ssu.h	8.11 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
stats.h	13.14 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
tcpmsg.h	3.07 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
time.h	1.66 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
timer.h	1.03 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
tkey.h	7.45 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
tsec.h	2.88 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
tsig.h	8.19 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
ttl.h	1.90 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
types.h	13.83 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
update.h	1.61 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
validator.h	6.99 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
version.h	868 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
view.h	34.45 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
xfrin.h	2.86 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
zone.h	59.44 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
zonekey.h	777 B	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive
zt.h	5.43 KB	lrw-r--r--	2025-11-06 07:45:36	Edit Download recursive recursive