name.c

bind 9.3结合mysql数据库

/*
 * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
 * Copyright (C) 1998-2003  Internet Software Consortium.
 *
 * 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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL ISC 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.
 */

/* $Id: name.c,v 1.127.2.7.2.11 2004/09/01 05:19:59 marka Exp $ */

#include <config.h>

#include <ctype.h>

#include <isc/buffer.h>
#include <isc/hash.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/string.h>
#include <isc/util.h>

#include <dns/compress.h>
#include <dns/name.h>
#include <dns/result.h>

#define VALID_NAME(n)	ISC_MAGIC_VALID(n, DNS_NAME_MAGIC)

typedef enum {
	ft_init = 0,
	ft_start,
	ft_ordinary,
	ft_initialescape,
	ft_escape,
	ft_escdecimal,
	ft_at
} ft_state;

typedef enum {
	fw_start = 0,
	fw_ordinary,
	fw_copy,
	fw_newcurrent
} fw_state;

static char digitvalue[256] = {
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,	/*16*/
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*32*/
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*48*/
	 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, -1, -1, -1, -1, -1, -1, /*64*/
	-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*80*/
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*96*/
	-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*112*/
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*128*/
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*256*/
};

static unsigned char maptolower[] = {
	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
	0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
	0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
	0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
	0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67,
	0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77,
	0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
	0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
	0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
	0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
	0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
	0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
	0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7,
	0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7,
	0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
};

#define CONVERTTOASCII(c)
#define CONVERTFROMASCII(c)

#define INIT_OFFSETS(name, var, default) \
	if (name->offsets != NULL) \
		var = name->offsets; \
	else \
		var = default;

#define SETUP_OFFSETS(name, var, default) \
	if (name->offsets != NULL) \
		var = name->offsets; \
	else { \
		var = default; \
		set_offsets(name, var, NULL); \
	}

/*
 * Note:  If additional attributes are added that should not be set for
 *	  empty names, MAKE_EMPTY() must be changed so it clears them.
 */
#define MAKE_EMPTY(name) \
do { \
	name->ndata = NULL; \
	name->length = 0; \
	name->labels = 0; \
	name->attributes &= ~DNS_NAMEATTR_ABSOLUTE; \
} while (0);

/*
 * A name is "bindable" if it can be set to point to a new value, i.e.
 * name->ndata and name->length may be changed.
 */
#define BINDABLE(name) \
	((name->attributes & (DNS_NAMEATTR_READONLY|DNS_NAMEATTR_DYNAMIC)) \
	 == 0)

/*
 * Note that the name data must be a char array, not a string
 * literal, to avoid compiler warnings about discarding
 * the const attribute of a string.
 */
static unsigned char root_ndata[] = { '\0' };
static unsigned char root_offsets[] = { 0 };

static dns_name_t root = 
{
	DNS_NAME_MAGIC,
	root_ndata, 1, 1,
	DNS_NAMEATTR_READONLY | DNS_NAMEATTR_ABSOLUTE,
	root_offsets, NULL,
	{(void *)-1, (void *)-1},
	{NULL, NULL}
};

/* XXXDCL make const? */
LIBDNS_EXTERNAL_DATA dns_name_t *dns_rootname = &root;

static unsigned char wild_ndata[] = { '\001', '*' };
static unsigned char wild_offsets[] = { 0 };

static dns_name_t wild =
{
	DNS_NAME_MAGIC,
	wild_ndata, 2, 1,
	DNS_NAMEATTR_READONLY,
	wild_offsets, NULL,
	{(void *)-1, (void *)-1},
	{NULL, NULL}
};

/* XXXDCL make const? */
LIBDNS_EXTERNAL_DATA dns_name_t *dns_wildcardname = &wild;

unsigned int
dns_fullname_hash(dns_name_t *name, isc_boolean_t case_sensitive);

static void
set_offsets(const dns_name_t *name, unsigned char *offsets,
	    dns_name_t *set_name);

void
dns_name_init(dns_name_t *name, unsigned char *offsets) {
	/*
	 * Initialize 'name'.
	 */
	DNS_NAME_INIT(name, offsets);
}

void
dns_name_reset(dns_name_t *name) {
	REQUIRE(VALID_NAME(name));
	REQUIRE(BINDABLE(name));

	DNS_NAME_RESET(name);
}

void
dns_name_invalidate(dns_name_t *name) {
	/*
	 * Make 'name' invalid.
	 */

	REQUIRE(VALID_NAME(name));

	name->magic = 0;
	name->ndata = NULL;
	name->length = 0;
	name->labels = 0;
	name->attributes = 0;
	name->offsets = NULL;
	name->buffer = NULL;
	ISC_LINK_INIT(name, link);
}

void
dns_name_setbuffer(dns_name_t *name, isc_buffer_t *buffer) {
	/*
	 * Dedicate a buffer for use with 'name'.
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE((buffer != NULL && name->buffer == NULL) ||
		(buffer == NULL));

	name->buffer = buffer;
}

isc_boolean_t
dns_name_hasbuffer(const dns_name_t *name) {
	/*
	 * Does 'name' have a dedicated buffer?
	 */

	REQUIRE(VALID_NAME(name));

	if (name->buffer != NULL)
		return (ISC_TRUE);

	return (ISC_FALSE);
}

isc_boolean_t
dns_name_isabsolute(const dns_name_t *name) {

	/*
	 * Does 'name' end in the root label?
	 */

	REQUIRE(VALID_NAME(name));

	if ((name->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
		return (ISC_TRUE);
	return (ISC_FALSE);
}

#define hyphenchar(c) ((c) == 0x2d)
#define asterchar(c) ((c) == 0x2a)
#define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \
		      || ((c) >= 0x61 && (c) <= 0x7a))
#define digitchar(c) ((c) >= 0x30 && (c) <= 0x39)
#define borderchar(c) (alphachar(c) || digitchar(c))
#define middlechar(c) (borderchar(c) || hyphenchar(c))
#define domainchar(c) ((c) > 0x20 && (c) < 0x7f)

isc_boolean_t
dns_name_ismailbox(const dns_name_t *name) {
	unsigned char *ndata, ch;
	unsigned int n;
	isc_boolean_t first;

	REQUIRE(VALID_NAME(name));
	REQUIRE(name->labels > 0);
	REQUIRE(name->attributes & DNS_NAMEATTR_ABSOLUTE);

	/* 
	 * Root label.
	 */
	if (name->length == 1)
		return (ISC_TRUE);

	ndata = name->ndata;
	n = *ndata++;
	INSIST(n <= 63);
	while (n--) {
		ch = *ndata++;
		if (!domainchar(ch))
			return (ISC_FALSE);
	}
	
	if (ndata == name->ndata + name->length)
		return (ISC_FALSE);

	/*
	 * RFC292/RFC1123 hostname.
	 */
	while (ndata < (name->ndata + name->length)) {
		n = *ndata++;
		INSIST(n <= 63);
		first = ISC_TRUE;
		while (n--) {
			ch = *ndata++;
			if (first || n == 0) {
				if (!borderchar(ch))
					return (ISC_FALSE);
			} else {
				if (!middlechar(ch))
					return (ISC_FALSE);
			}
			first = ISC_FALSE;
		}
	}
	return (ISC_TRUE);
}

isc_boolean_t
dns_name_ishostname(const dns_name_t *name, isc_boolean_t wildcard) {
	unsigned char *ndata, ch;
	unsigned int n;
	isc_boolean_t first;

	REQUIRE(VALID_NAME(name));
	REQUIRE(name->labels > 0);
	REQUIRE(name->attributes & DNS_NAMEATTR_ABSOLUTE);
	
	/* 
	 * Root label.
	 */
	if (name->length == 1)
		return (ISC_TRUE);

	/*
	 * Skip wildcard if this is a ownername.
	 */
	ndata = name->ndata;
	if (wildcard && ndata[0] == 1 && ndata[1] == '*')
		ndata += 2;

	/*
	 * RFC292/RFC1123 hostname.
	 */
	while (ndata < (name->ndata + name->length)) {
		n = *ndata++;
		INSIST(n <= 63);
		first = ISC_TRUE;
		while (n--) {
			ch = *ndata++;
			if (first || n == 0) {
				if (!borderchar(ch))
					return (ISC_FALSE);
			} else {
				if (!middlechar(ch))
					return (ISC_FALSE);
			}
			first = ISC_FALSE;
		}
	}
	return (ISC_TRUE);
}

isc_boolean_t
dns_name_iswildcard(const dns_name_t *name) {
	unsigned char *ndata;

	/*
	 * Is 'name' a wildcard name?
	 */

	REQUIRE(VALID_NAME(name));
	REQUIRE(name->labels > 0);

	if (name->length >= 2) {
		ndata = name->ndata;
		if (ndata[0] == 1 && ndata[1] == '*')
			return (ISC_TRUE);
	}

	return (ISC_FALSE);
}

static inline unsigned int
name_hash(dns_name_t *name, isc_boolean_t case_sensitive) {
	unsigned int length;
	const unsigned char *s;
	unsigned int h = 0;
	unsigned char c;

	length = name->length;
	if (length > 16)
		length = 16;

	/*
	 * This hash function is similar to the one Ousterhout
	 * uses in Tcl.
	 */
	s = name->ndata;
	if (case_sensitive) {
		while (length > 0) {
			h += ( h << 3 ) + *s;
			s++;
			length--;
		}
	} else {
		while (length > 0) {
			c = maptolower[*s];
			h += ( h << 3 ) + c;
			s++;
			length--;
		}
	}

	return (h);
}

unsigned int
dns_name_hash(dns_name_t *name, isc_boolean_t case_sensitive) {
	/*
	 * Provide a hash value for 'name'.
	 */
	REQUIRE(VALID_NAME(name));

	if (name->labels == 0)
		return (0);

	return (name_hash(name, case_sensitive));
}

unsigned int
dns_name_fullhash(dns_name_t *name, isc_boolean_t case_sensitive) {
	/*
	 * Provide a hash value for 'name'.
	 */
	REQUIRE(VALID_NAME(name));

	if (name->labels == 0)
		return (0);

	return (isc_hash_calc((const unsigned char *)name->ndata,
			      name->length, case_sensitive));
}

unsigned int
dns_fullname_hash(dns_name_t *name, isc_boolean_t case_sensitive) {
	/*
	 * This function was deprecated due to the breakage of the name space
	 * convention.  We only keep this internally to provide binary backward
	 * compatibility.
	 */
	REQUIRE(VALID_NAME(name));

	return (dns_name_fullhash(name, case_sensitive));
}

unsigned int
dns_name_hashbylabel(dns_name_t *name, isc_boolean_t case_sensitive) {
	unsigned char *offsets;
	dns_offsets_t odata;
	dns_name_t tname;
	unsigned int h = 0;
	unsigned int i;

	/*
	 * Provide a hash value for 'name'.
	 */
	REQUIRE(VALID_NAME(name));

	if (name->labels == 0)
		return (0);
	else if (name->labels == 1)
		return (name_hash(name, case_sensitive));

	SETUP_OFFSETS(name, offsets, odata);
	DNS_NAME_INIT(&tname, NULL);
	tname.labels = 1;
	h = 0;
	for (i = 0; i < name->labels; i++) {
		tname.ndata = name->ndata + offsets[i];
		if (i == name->labels - 1)
			tname.length = name->length - offsets[i];
		else
			tname.length = offsets[i + 1] - offsets[i];
		h += name_hash(&tname, case_sensitive);
	}

	return (h);
}

dns_namereln_t
dns_name_fullcompare(const dns_name_t *name1, const dns_name_t *name2,
		     int *orderp, unsigned int *nlabelsp)
{
	unsigned int l1, l2, l, count1, count2, count, nlabels;
	int cdiff, ldiff, chdiff;
	unsigned char *label1, *label2;
	unsigned char *offsets1, *offsets2;
	dns_offsets_t odata1, odata2;
	dns_namereln_t namereln = dns_namereln_none;

	/*
	 * Determine the relative ordering under the DNSSEC order relation of
	 * 'name1' and 'name2', and also determine the hierarchical
	 * relationship of the names.
	 *
	 * Note: It makes no sense for one of the names to be relative and the
	 * other absolute.  If both names are relative, then to be meaningfully
	 * compared the caller must ensure that they are both relative to the
	 * same domain.
	 */

	REQUIRE(VALID_NAME(name1));
	REQUIRE(VALID_NAME(name2));
	REQUIRE(orderp != NULL);
	REQUIRE(nlabelsp != NULL);
	/*
	 * Either name1 is absolute and name2 is absolute, or neither is.
	 */
	REQUIRE((name1->attributes & DNS_NAMEATTR_ABSOLUTE) ==
		(name2->attributes & DNS_NAMEATTR_ABSOLUTE));

	SETUP_OFFSETS(name1, offsets1, odata1);
	SETUP_OFFSETS(name2, offsets2, odata2);

	nlabels = 0;
	l1 = name1->labels;
	l2 = name2->labels;
	ldiff = (int)l1 - (int)l2;
	if (ldiff < 0)
		l = l1;
	else
		l = l2;

	while (l > 0) {
		l--;
		l1--;
		l2--;
		label1 = &name1->ndata[offsets1[l1]];
		label2 = &name2->ndata[offsets2[l2]];
		count1 = *label1++;
		count2 = *label2++;

		/*
		 * We dropped bitstring labels, and we don't support any
		 * other extended label types.
		 */