name.c revision 5855fd79e375c74fc9df57ce0b4c4ef1b9fcdc3e
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill/*
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * Copyright (C) 2004-2015 Internet Systems Consortium, Inc. ("ISC")
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * Copyright (C) 1998-2003 Internet Software Consortium.
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill *
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * Permission to use, copy, modify, and/or distribute this software for any
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * purpose with or without fee is hereby granted, provided that the above
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * copyright notice and this permission notice appear in all copies.
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill *
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill * PERFORMANCE OF THIS SOFTWARE.
1767006bb066ef500b90b432fba79d63d0d09b36Bryan Cantrill */
/* $Id$ */
/*! \file */
#include <config.h>
#include <ctype.h>
#include <stdlib.h>
#include <isc/buffer.h>
#include <isc/hash.h>
#include <isc/mem.h>
#include <isc/once.h>
#include <isc/print.h>
#include <isc/string.h>
#include <isc/thread.h>
#include <isc/util.h>
#include <dns/compress.h>
#include <dns/fixedname.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_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);
/*
* dns_name_t to text post-conversion procedure.
*/
#ifdef ISC_PLATFORM_USETHREADS
static int thread_key_initialized = 0;
static isc_mutex_t thread_key_mutex;
static isc_mem_t *thread_key_mctx = NULL;
static isc_thread_key_t totext_filter_proc_key;
static isc_once_t once = ISC_ONCE_INIT;
#else
static dns_name_totextfilter_t totext_filter_proc = NULL;
#endif
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);
}
isc_boolean_t
dns_name_isvalid(const dns_name_t *name) {
unsigned char *ndata, *offsets;
unsigned int offset, count, length, nlabels;
if (!VALID_NAME(name))
return (ISC_FALSE);
if (name->length > 255U || name->labels > 127U)
return (ISC_FALSE);
ndata = name->ndata;
length = name->length;
offsets = name->offsets;
offset = 0;
nlabels = 0;
while (offset != length) {
count = *ndata;
if (count > 63U)
return (ISC_FALSE);
if (offsets != NULL && offsets[nlabels] != offset)
return (ISC_FALSE);
nlabels++;
offset += count + 1;
ndata += count + 1;
if (offset > length)
return (ISC_FALSE);
if (count == 0)
break;
}
if (nlabels != name->labels || offset != name->length)
return (ISC_FALSE);
return (ISC_TRUE);
}
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);
}
isc_boolean_t
dns_name_internalwildcard(const dns_name_t *name) {
unsigned char *ndata;
unsigned int count;
unsigned int label;
/*
* Does 'name' contain a internal wildcard?
*/
REQUIRE(VALID_NAME(name));
REQUIRE(name->labels > 0);
/*
* Skip first label.
*/
ndata = name->ndata;
count = *ndata++;
INSIST(count <= 63);
ndata += count;
label = 1;
/*
* Check all but the last of the remaining labels.
*/
while (label + 1 < name->labels) {
count = *ndata++;
INSIST(count <= 63);
if (count == 1 && *ndata == '*')
return (ISC_TRUE);
ndata += count;
label++;
}
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));
if (name1 == name2) {
*orderp = 0;
*nlabelsp = name1->labels;
return (dns_namereln_equal);
}
SETUP_OFFSETS(name1, offsets1, odata1);
SETUP_OFFSETS(name2, offsets2, odata2);
nlabels = 0;
l1 = name1->labels;
l2 = name2->labels;
if (l2 > l1) {
l = l1;
ldiff = 0 - (l2 - l1);
} else {
l = l2;
ldiff = l1 - 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.
*/
INSIST(count1 <= 63 && count2 <= 63);
cdiff = (int)count1 - (int)count2;
if (cdiff < 0)
count = count1;
else
count = count2;
while (count > 0) {
chdiff = (int)maptolower[*label1] -
(int)maptolower[*label2];
if (chdiff != 0) {
*orderp = chdiff;
goto done;
}
count--;
label1++;
label2++;
}
if (cdiff != 0) {
*orderp = cdiff;
goto done;
}
nlabels++;
}
*orderp = ldiff;
if (ldiff < 0)
namereln = dns_namereln_contains;
else if (ldiff > 0)
namereln = dns_namereln_subdomain;
else
namereln = dns_namereln_equal;
done:
*nlabelsp = nlabels;
if (nlabels > 0 && namereln == dns_namereln_none)
namereln = dns_namereln_commonancestor;
return (namereln);
}
int
dns_name_compare(const dns_name_t *name1, const dns_name_t *name2) {
int order;
unsigned int nlabels;
/*
* Determine the relative ordering under the DNSSEC order relation of
* 'name1' and 'name2'.
*
* 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.
*/
(void)dns_name_fullcompare(name1, name2, &order, &nlabels);
return (order);
}
isc_boolean_t
dns_name_equal(const dns_name_t *name1, const dns_name_t *name2) {
unsigned int l, count;
unsigned char c;
unsigned char *label1, *label2;
/*
* Are 'name1' and 'name2' equal?
*
* 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));
/*
* Either name1 is absolute and name2 is absolute, or neither is.
*/
REQUIRE((name1->attributes & DNS_NAMEATTR_ABSOLUTE) ==
(name2->attributes & DNS_NAMEATTR_ABSOLUTE));
if (name1 == name2)
return (ISC_TRUE);
if (name1->length != name2->length)
return (ISC_FALSE);
l = name1->labels;
if (l != name2->labels)
return (ISC_FALSE);
label1 = name1->ndata;
label2 = name2->ndata;
while (l > 0) {
l--;
count = *label1++;
if (count != *label2++)
return (ISC_FALSE);
INSIST(count <= 63); /* no bitstring support */
while (count > 0) {
count--;
c = maptolower[*label1++];
if (c != maptolower[*label2++])
return (ISC_FALSE);
}
}
return (ISC_TRUE);
}
isc_boolean_t
dns_name_caseequal(const dns_name_t *name1, const dns_name_t *name2) {
/*
* Are 'name1' and 'name2' equal?
*
* 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));
/*
* Either name1 is absolute and name2 is absolute, or neither is.
*/
REQUIRE((name1->attributes & DNS_NAMEATTR_ABSOLUTE) ==
(name2->attributes & DNS_NAMEATTR_ABSOLUTE));
if (name1->length != name2->length)
return (ISC_FALSE);
if (memcmp(name1->ndata, name2->ndata, name1->length) != 0)
return (ISC_FALSE);
return (ISC_TRUE);
}
int
dns_name_rdatacompare(const dns_name_t *name1, const dns_name_t *name2) {
unsigned int l1, l2, l, count1, count2, count;
unsigned char c1, c2;
unsigned char *label1, *label2;
/*
* Compare two absolute names as rdata.
*/
REQUIRE(VALID_NAME(name1));
REQUIRE(name1->labels > 0);
REQUIRE((name1->attributes & DNS_NAMEATTR_ABSOLUTE) != 0);
REQUIRE(VALID_NAME(name2));
REQUIRE(name2->labels > 0);
REQUIRE((name2->attributes & DNS_NAMEATTR_ABSOLUTE) != 0);
l1 = name1->labels;
l2 = name2->labels;
l = (l1 < l2) ? l1 : l2;
label1 = name1->ndata;
label2 = name2->ndata;
while (l > 0) {
l--;
count1 = *label1++;
count2 = *label2++;
/* no bitstring support */
INSIST(count1 <= 63 && count2 <= 63);
if (count1 != count2)
return ((count1 < count2) ? -1 : 1);
count = count1;
while (count > 0) {
count--;
c1 = maptolower[*label1++];
c2 = maptolower[*label2++];
if (c1 < c2)
return (-1);
else if (c1 > c2)
return (1);
}
}
/*
* If one name had more labels than the other, their common
* prefix must have been different because the shorter name
* ended with the root label and the longer one can't have
* a root label in the middle of it. Therefore, if we get
* to this point, the lengths must be equal.
*/
INSIST(l1 == l2);
return (0);
}
isc_boolean_t
dns_name_issubdomain(const dns_name_t *name1, const dns_name_t *name2) {
int order;
unsigned int nlabels;
dns_namereln_t namereln;
/*
* Is 'name1' a subdomain of 'name2'?
*
* 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.
*/
namereln = dns_name_fullcompare(name1, name2, &order, &nlabels);
if (namereln == dns_namereln_subdomain ||
namereln == dns_namereln_equal)
return (ISC_TRUE);
return (ISC_FALSE);
}
isc_boolean_t
dns_name_matcheswildcard(const dns_name_t *name, const dns_name_t *wname) {
int order;
unsigned int nlabels, labels;
dns_name_t tname;
REQUIRE(VALID_NAME(name));
REQUIRE(name->labels > 0);
REQUIRE(VALID_NAME(wname));
labels = wname->labels;
REQUIRE(labels > 0);
REQUIRE(dns_name_iswildcard(wname));
#if defined(__clang__) && \
( __clang_major__ < 3 || (__clang_major__ == 3 && __clang_minor__ < 2))
memset(&tname, 0, sizeof(tname));
#endif
DNS_NAME_INIT(&tname, NULL);
dns_name_getlabelsequence(wname, 1, labels - 1, &tname);
if (dns_name_fullcompare(name, &tname, &order, &nlabels) ==
dns_namereln_subdomain)
return (ISC_TRUE);
return (ISC_FALSE);
}
unsigned int
dns_name_countlabels(const dns_name_t *name) {
/*
* How many labels does 'name' have?
*/
REQUIRE(VALID_NAME(name));
ENSURE(name->labels <= 128);
return (name->labels);
}
void
dns_name_getlabel(const dns_name_t *name, unsigned int n, dns_label_t *label) {
unsigned char *offsets;
dns_offsets_t odata;
/*
* Make 'label' refer to the 'n'th least significant label of 'name'.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(name->labels > 0);
REQUIRE(n < name->labels);
REQUIRE(label != NULL);
SETUP_OFFSETS(name, offsets, odata);
label->base = &name->ndata[offsets[n]];
if (n == name->labels - 1)
label->length = name->length - offsets[n];
else
label->length = offsets[n + 1] - offsets[n];
}
void
dns_name_getlabelsequence(const dns_name_t *source,
unsigned int first, unsigned int n,
dns_name_t *target)
{
unsigned char *offsets;
dns_offsets_t odata;
unsigned int firstoffset, endoffset;
/*
* Make 'target' refer to the 'n' labels including and following
* 'first' in 'source'.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(VALID_NAME(target));
REQUIRE(first <= source->labels);
REQUIRE(n <= source->labels - first); /* note first+n could overflow */
REQUIRE(BINDABLE(target));
SETUP_OFFSETS(source, offsets, odata);
if (first == source->labels)
firstoffset = source->length;
else
firstoffset = offsets[first];
if (first + n == source->labels)
endoffset = source->length;
else
endoffset = offsets[first + n];
target->ndata = &source->ndata[firstoffset];
target->length = endoffset - firstoffset;
if (first + n == source->labels && n > 0 &&
(source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
target->attributes |= DNS_NAMEATTR_ABSOLUTE;
else
target->attributes &= ~DNS_NAMEATTR_ABSOLUTE;
target->labels = n;
/*
* If source and target are the same, and we're making target
* a prefix of source, the offsets table is correct already
* so we don't need to call set_offsets().
*/
if (target->offsets != NULL &&
(target != source || first != 0))
set_offsets(target, target->offsets, NULL);
}
void
dns_name_clone(const dns_name_t *source, dns_name_t *target) {
/*
* Make 'target' refer to the same name as 'source'.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(VALID_NAME(target));
REQUIRE(BINDABLE(target));
target->ndata = source->ndata;
target->length = source->length;
target->labels = source->labels;
target->attributes = source->attributes &
(unsigned int)~(DNS_NAMEATTR_READONLY | DNS_NAMEATTR_DYNAMIC |
DNS_NAMEATTR_DYNOFFSETS);
if (target->offsets != NULL && source->labels > 0) {
if (source->offsets != NULL)
memmove(target->offsets, source->offsets,
source->labels);
else
set_offsets(target, target->offsets, NULL);
}
}
void
dns_name_fromregion(dns_name_t *name, const isc_region_t *r) {
unsigned char *offsets;
dns_offsets_t odata;
unsigned int len;
isc_region_t r2;
/*
* Make 'name' refer to region 'r'.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(r != NULL);
REQUIRE(BINDABLE(name));
INIT_OFFSETS(name, offsets, odata);
if (name->buffer != NULL) {
isc_buffer_clear(name->buffer);
isc_buffer_availableregion(name->buffer, &r2);
len = (r->length < r2.length) ? r->length : r2.length;
if (len > DNS_NAME_MAXWIRE)
len = DNS_NAME_MAXWIRE;
memmove(r2.base, r->base, len);
name->ndata = r2.base;
name->length = len;
} else {
name->ndata = r->base;
name->length = (r->length <= DNS_NAME_MAXWIRE) ?
r->length : DNS_NAME_MAXWIRE;
}
if (r->length > 0)
set_offsets(name, offsets, name);
else {
name->labels = 0;
name->attributes &= ~DNS_NAMEATTR_ABSOLUTE;
}
if (name->buffer != NULL)
isc_buffer_add(name->buffer, name->length);
}
void
dns_name_toregion(dns_name_t *name, isc_region_t *r) {
/*
* Make 'r' refer to 'name'.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(r != NULL);
DNS_NAME_TOREGION(name, r);
}
isc_result_t
dns_name_fromtext(dns_name_t *name, isc_buffer_t *source,
const dns_name_t *origin, unsigned int options,
isc_buffer_t *target)
{
unsigned char *ndata, *label = NULL;
char *tdata;
char c;
ft_state state;
unsigned int value = 0, count = 0;
unsigned int n1 = 0, n2 = 0;
unsigned int tlen, nrem, nused, digits = 0, labels, tused;
isc_boolean_t done;
unsigned char *offsets;
dns_offsets_t odata;
isc_boolean_t downcase;
/*
* Convert the textual representation of a DNS name at source
* into uncompressed wire form stored in target.
*
* Notes:
* Relative domain names will have 'origin' appended to them
* unless 'origin' is NULL, in which case relative domain names
* will remain relative.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(ISC_BUFFER_VALID(source));
REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
(target == NULL && ISC_BUFFER_VALID(name->buffer)));
downcase = ISC_TF((options & DNS_NAME_DOWNCASE) != 0);
if (target == NULL && name->buffer != NULL) {
target = name->buffer;
isc_buffer_clear(target);
}
REQUIRE(BINDABLE(name));
INIT_OFFSETS(name, offsets, odata);
offsets[0] = 0;
/*
* Make 'name' empty in case of failure.
*/
MAKE_EMPTY(name);
/*
* Set up the state machine.
*/
tdata = (char *)source->base + source->current;
tlen = isc_buffer_remaininglength(source);
tused = 0;
ndata = isc_buffer_used(target);
nrem = isc_buffer_availablelength(target);
if (nrem > 255)
nrem = 255;
nused = 0;
labels = 0;
done = ISC_FALSE;
state = ft_init;
while (nrem > 0 && tlen > 0 && !done) {
c = *tdata++;
tlen--;
tused++;
switch (state) {
case ft_init:
/*
* Is this the root name?
*/
if (c == '.') {
if (tlen != 0)
return (DNS_R_EMPTYLABEL);
labels++;
*ndata++ = 0;
nrem--;
nused++;
done = ISC_TRUE;
break;
}
if (c == '@' && tlen == 0) {
state = ft_at;
break;
}
/* FALLTHROUGH */
case ft_start:
label = ndata;
ndata++;
nrem--;
nused++;
count = 0;
if (c == '\\') {
state = ft_initialescape;
break;
}
state = ft_ordinary;
if (nrem == 0)
return (ISC_R_NOSPACE);
/* FALLTHROUGH */
case ft_ordinary:
if (c == '.') {
if (count == 0)
return (DNS_R_EMPTYLABEL);
*label = count;
labels++;
INSIST(labels <= 127);
offsets[labels] = nused;
if (tlen == 0) {
labels++;
*ndata++ = 0;
nrem--;
nused++;
done = ISC_TRUE;
}
state = ft_start;
} else if (c == '\\') {
state = ft_escape;
} else {
if (count >= 63)
return (DNS_R_LABELTOOLONG);
count++;
CONVERTTOASCII(c);
if (downcase)
c = maptolower[c & 0xff];
*ndata++ = c;
nrem--;
nused++;
}
break;
case ft_initialescape:
if (c == '[') {
/*
* This looks like a bitstring label, which
* was deprecated. Intentionally drop it.
*/
return (DNS_R_BADLABELTYPE);
}
state = ft_escape;
POST(state);
/* FALLTHROUGH */
case ft_escape:
if (!isdigit(c & 0xff)) {
if (count >= 63)
return (DNS_R_LABELTOOLONG);
count++;
CONVERTTOASCII(c);
if (downcase)
c = maptolower[c & 0xff];
*ndata++ = c;
nrem--;
nused++;
state = ft_ordinary;
break;
}
digits = 0;
value = 0;
state = ft_escdecimal;
/* FALLTHROUGH */
case ft_escdecimal:
if (!isdigit(c & 0xff))
return (DNS_R_BADESCAPE);
value *= 10;
value += digitvalue[c & 0xff];
digits++;
if (digits == 3) {
if (value > 255)
return (DNS_R_BADESCAPE);
if (count >= 63)
return (DNS_R_LABELTOOLONG);
count++;
if (downcase)
value = maptolower[value];
*ndata++ = value;
nrem--;
nused++;
state = ft_ordinary;
}
break;
default:
FATAL_ERROR(__FILE__, __LINE__,
"Unexpected state %d", state);
/* Does not return. */
}
}
if (!done) {
if (nrem == 0)
return (ISC_R_NOSPACE);
INSIST(tlen == 0);
if (state != ft_ordinary && state != ft_at)
return (ISC_R_UNEXPECTEDEND);
if (state == ft_ordinary) {
INSIST(count != 0);
*label = count;
labels++;
INSIST(labels <= 127);
offsets[labels] = nused;
}
if (origin != NULL) {
if (nrem < origin->length)
return (ISC_R_NOSPACE);
label = origin->ndata;
n1 = origin->length;
nrem -= n1;
POST(nrem);
while (n1 > 0) {
n2 = *label++;
INSIST(n2 <= 63); /* no bitstring support */
*ndata++ = n2;
n1 -= n2 + 1;
nused += n2 + 1;
while (n2 > 0) {
c = *label++;
if (downcase)
c = maptolower[c & 0xff];
*ndata++ = c;
n2--;
}
labels++;
if (n1 > 0) {
INSIST(labels <= 127);
offsets[labels] = nused;
}
}
if ((origin->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
name->attributes |= DNS_NAMEATTR_ABSOLUTE;
}
} else
name->attributes |= DNS_NAMEATTR_ABSOLUTE;
name->ndata = (unsigned char *)target->base + target->used;
name->labels = labels;
name->length = nused;
isc_buffer_forward(source, tused);
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
}
#ifdef ISC_PLATFORM_USETHREADS
static void
free_specific(void *arg) {
dns_name_totextfilter_t *mem = arg;
isc_mem_put(thread_key_mctx, mem, sizeof(*mem));
/* Stop use being called again. */
(void)isc_thread_key_setspecific(totext_filter_proc_key, NULL);
}
static void
thread_key_mutex_init(void) {
RUNTIME_CHECK(isc_mutex_init(&thread_key_mutex) == ISC_R_SUCCESS);
}
static isc_result_t
totext_filter_proc_key_init(void) {
isc_result_t result;
/*
* We need the call to isc_once_do() to support profiled mutex
* otherwise thread_key_mutex could be initialized at compile time.
*/
result = isc_once_do(&once, thread_key_mutex_init);
if (result != ISC_R_SUCCESS)
return (result);
if (!thread_key_initialized) {
LOCK(&thread_key_mutex);
if (thread_key_mctx == NULL)
result = isc_mem_create2(0, 0, &thread_key_mctx, 0);
if (result != ISC_R_SUCCESS)
goto unlock;
isc_mem_setname(thread_key_mctx, "threadkey", NULL);
isc_mem_setdestroycheck(thread_key_mctx, ISC_FALSE);
if (!thread_key_initialized &&
isc_thread_key_create(&totext_filter_proc_key,
free_specific) != 0) {
result = ISC_R_FAILURE;
isc_mem_detach(&thread_key_mctx);
} else
thread_key_initialized = 1;
unlock:
UNLOCK(&thread_key_mutex);
}
return (result);
}
#endif
isc_result_t
dns_name_totext(const dns_name_t *name, isc_boolean_t omit_final_dot,
isc_buffer_t *target)
{
unsigned int options = DNS_NAME_MASTERFILE;
if (omit_final_dot)
options |= DNS_NAME_OMITFINALDOT;
return (dns_name_totext2(name, options, target));
}
isc_result_t
dns_name_toprincipal(const dns_name_t *name, isc_buffer_t *target) {
return (dns_name_totext2(name, DNS_NAME_OMITFINALDOT, target));
}
isc_result_t
dns_name_totext2(const dns_name_t *name, unsigned int options,
isc_buffer_t *target)
{
unsigned char *ndata;
char *tdata;
unsigned int nlen, tlen;
unsigned char c;
unsigned int trem, count;
unsigned int labels;
isc_boolean_t saw_root = ISC_FALSE;
unsigned int oused = target->used;
#ifdef ISC_PLATFORM_USETHREADS
dns_name_totextfilter_t *mem;
dns_name_totextfilter_t totext_filter_proc = NULL;
isc_result_t result;
#endif
isc_boolean_t omit_final_dot =
ISC_TF(options & DNS_NAME_OMITFINALDOT);
/*
* This function assumes the name is in proper uncompressed
* wire format.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(ISC_BUFFER_VALID(target));
#ifdef ISC_PLATFORM_USETHREADS
result = totext_filter_proc_key_init();
if (result != ISC_R_SUCCESS)
return (result);
#endif
ndata = name->ndata;
nlen = name->length;
labels = name->labels;
tdata = isc_buffer_used(target);
tlen = isc_buffer_availablelength(target);
trem = tlen;
if (labels == 0 && nlen == 0) {
/*
* Special handling for an empty name.
*/
if (trem == 0)
return (ISC_R_NOSPACE);
/*
* The names of these booleans are misleading in this case.
* This empty name is not necessarily from the root node of
* the DNS root zone, nor is a final dot going to be included.
* They need to be set this way, though, to keep the "@"
* from being trounced.
*/
saw_root = ISC_TRUE;
omit_final_dot = ISC_FALSE;
*tdata++ = '@';
trem--;
/*
* Skip the while() loop.
*/
nlen = 0;
} else if (nlen == 1 && labels == 1 && *ndata == '\0') {
/*
* Special handling for the root label.
*/
if (trem == 0)
return (ISC_R_NOSPACE);
saw_root = ISC_TRUE;
omit_final_dot = ISC_FALSE;
*tdata++ = '.';
trem--;
/*
* Skip the while() loop.
*/
nlen = 0;
}
while (labels > 0 && nlen > 0 && trem > 0) {
labels--;
count = *ndata++;
nlen--;
if (count == 0) {
saw_root = ISC_TRUE;
break;
}
if (count < 64) {
INSIST(nlen >= count);
while (count > 0) {
c = *ndata;
switch (c) {
/* Special modifiers in zone files. */
case 0x40: /* '@' */
case 0x24: /* '$' */
if ((options & DNS_NAME_MASTERFILE) == 0)
goto no_escape;
/* FALLTHROUGH */
case 0x22: /* '"' */
case 0x28: /* '(' */
case 0x29: /* ')' */
case 0x2E: /* '.' */
case 0x3B: /* ';' */
case 0x5C: /* '\\' */
if (trem < 2)
return (ISC_R_NOSPACE);
*tdata++ = '\\';
CONVERTFROMASCII(c);
*tdata++ = c;
ndata++;
trem -= 2;
nlen--;
break;
no_escape:
default:
if (c > 0x20 && c < 0x7f) {
if (trem == 0)
return (ISC_R_NOSPACE);
CONVERTFROMASCII(c);
*tdata++ = c;
ndata++;
trem--;
nlen--;
} else {
if (trem < 4)
return (ISC_R_NOSPACE);
*tdata++ = 0x5c;
*tdata++ = 0x30 +
((c / 100) % 10);
*tdata++ = 0x30 +
((c / 10) % 10);
*tdata++ = 0x30 + (c % 10);
trem -= 4;
ndata++;
nlen--;
}
}
count--;
}
} else {
FATAL_ERROR(__FILE__, __LINE__,
"Unexpected label type %02x", count);
/* NOTREACHED */
}
/*
* The following assumes names are absolute. If not, we
* fix things up later. Note that this means that in some
* cases one more byte of text buffer is required than is
* needed in the final output.
*/
if (trem == 0)
return (ISC_R_NOSPACE);
*tdata++ = '.';
trem--;
}
if (nlen != 0 && trem == 0)
return (ISC_R_NOSPACE);
if (!saw_root || omit_final_dot)
trem++;
isc_buffer_add(target, tlen - trem);
#ifdef ISC_PLATFORM_USETHREADS
mem = isc_thread_key_getspecific(totext_filter_proc_key);
if (mem != NULL)
totext_filter_proc = *mem;
#endif
if (totext_filter_proc != NULL)
return ((*totext_filter_proc)(target, oused, saw_root));
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_tofilenametext(dns_name_t *name, isc_boolean_t omit_final_dot,
isc_buffer_t *target)
{
unsigned char *ndata;
char *tdata;
unsigned int nlen, tlen;
unsigned char c;
unsigned int trem, count;
unsigned int labels;
/*
* This function assumes the name is in proper uncompressed
* wire format.
*/
REQUIRE(VALID_NAME(name));
REQUIRE((name->attributes & DNS_NAMEATTR_ABSOLUTE) != 0);
REQUIRE(ISC_BUFFER_VALID(target));
ndata = name->ndata;
nlen = name->length;
labels = name->labels;
tdata = isc_buffer_used(target);
tlen = isc_buffer_availablelength(target);
trem = tlen;
if (nlen == 1 && labels == 1 && *ndata == '\0') {
/*
* Special handling for the root label.
*/
if (trem == 0)
return (ISC_R_NOSPACE);
omit_final_dot = ISC_FALSE;
*tdata++ = '.';
trem--;
/*
* Skip the while() loop.
*/
nlen = 0;
}
while (labels > 0 && nlen > 0 && trem > 0) {
labels--;
count = *ndata++;
nlen--;
if (count == 0)
break;
if (count < 64) {
INSIST(nlen >= count);
while (count > 0) {
c = *ndata;
if ((c >= 0x30 && c <= 0x39) || /* digit */
(c >= 0x41 && c <= 0x5A) || /* uppercase */
(c >= 0x61 && c <= 0x7A) || /* lowercase */
c == 0x2D || /* hyphen */
c == 0x5F) /* underscore */
{
if (trem == 0)
return (ISC_R_NOSPACE);
/* downcase */
if (c >= 0x41 && c <= 0x5A)
c += 0x20;
CONVERTFROMASCII(c);
*tdata++ = c;
ndata++;
trem--;
nlen--;
} else {
if (trem < 3)
return (ISC_R_NOSPACE);
sprintf(tdata, "%%%02X", c);
tdata += 3;
trem -= 3;
ndata++;
nlen--;
}
count--;
}
} else {
FATAL_ERROR(__FILE__, __LINE__,
"Unexpected label type %02x", count);
/* NOTREACHED */
}
/*
* The following assumes names are absolute. If not, we
* fix things up later. Note that this means that in some
* cases one more byte of text buffer is required than is
* needed in the final output.
*/
if (trem == 0)
return (ISC_R_NOSPACE);
*tdata++ = '.';
trem--;
}
if (nlen != 0 && trem == 0)
return (ISC_R_NOSPACE);
if (omit_final_dot)
trem++;
isc_buffer_add(target, tlen - trem);
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_downcase(dns_name_t *source, dns_name_t *name, isc_buffer_t *target) {
unsigned char *sndata, *ndata;
unsigned int nlen, count, labels;
isc_buffer_t buffer;
/*
* Downcase 'source'.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(VALID_NAME(name));
if (source == name) {
REQUIRE((name->attributes & DNS_NAMEATTR_READONLY) == 0);
isc_buffer_init(&buffer, source->ndata, source->length);
target = &buffer;
ndata = source->ndata;
} else {
REQUIRE(BINDABLE(name));
REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
(target == NULL && ISC_BUFFER_VALID(name->buffer)));
if (target == NULL) {
target = name->buffer;
isc_buffer_clear(name->buffer);
}
ndata = (unsigned char *)target->base + target->used;
name->ndata = ndata;
}
sndata = source->ndata;
nlen = source->length;
labels = source->labels;
if (nlen > (target->length - target->used)) {
MAKE_EMPTY(name);
return (ISC_R_NOSPACE);
}
while (labels > 0 && nlen > 0) {
labels--;
count = *sndata++;
*ndata++ = count;
nlen--;
if (count < 64) {
INSIST(nlen >= count);
while (count > 0) {
*ndata++ = maptolower[(*sndata++)];
nlen--;
count--;
}
} else {
FATAL_ERROR(__FILE__, __LINE__,
"Unexpected label type %02x", count);
/* Does not return. */
}
}
if (source != name) {
name->labels = source->labels;
name->length = source->length;
if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
name->attributes = DNS_NAMEATTR_ABSOLUTE;
else
name->attributes = 0;
if (name->labels > 0 && name->offsets != NULL)
set_offsets(name, name->offsets, NULL);
}
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
}
static void
set_offsets(const dns_name_t *name, unsigned char *offsets,
dns_name_t *set_name)
{
unsigned int offset, count, length, nlabels;
unsigned char *ndata;
isc_boolean_t absolute;
ndata = name->ndata;
length = name->length;
offset = 0;
nlabels = 0;
absolute = ISC_FALSE;
while (offset != length) {
INSIST(nlabels < 128);
offsets[nlabels++] = offset;
count = *ndata++;
offset++;
INSIST(count <= 63);
offset += count;
ndata += count;
INSIST(offset <= length);
if (count == 0) {
absolute = ISC_TRUE;
break;
}
}
if (set_name != NULL) {
INSIST(set_name == name);
set_name->labels = nlabels;
set_name->length = offset;
if (absolute)
set_name->attributes |= DNS_NAMEATTR_ABSOLUTE;
else
set_name->attributes &= ~DNS_NAMEATTR_ABSOLUTE;
}
INSIST(nlabels == name->labels);
INSIST(offset == name->length);
}
isc_result_t
dns_name_fromwire(dns_name_t *name, isc_buffer_t *source,
dns_decompress_t *dctx, unsigned int options,
isc_buffer_t *target)
{
unsigned char *cdata, *ndata;
unsigned int cused; /* Bytes of compressed name data used */
unsigned int nused, labels, n, nmax;
unsigned int current, new_current, biggest_pointer;
isc_boolean_t done;
fw_state state = fw_start;
unsigned int c;
unsigned char *offsets;
dns_offsets_t odata;
isc_boolean_t downcase;
isc_boolean_t seen_pointer;
/*
* Copy the possibly-compressed name at source into target,
* decompressing it. Loop prevention is performed by checking
* the new pointer against biggest_pointer.
*/
REQUIRE(VALID_NAME(name));
REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
(target == NULL && ISC_BUFFER_VALID(name->buffer)));
downcase = ISC_TF((options & DNS_NAME_DOWNCASE) != 0);
if (target == NULL && name->buffer != NULL) {
target = name->buffer;
isc_buffer_clear(target);
}
REQUIRE(dctx != NULL);
REQUIRE(BINDABLE(name));
INIT_OFFSETS(name, offsets, odata);
/*
* Make 'name' empty in case of failure.
*/
MAKE_EMPTY(name);
/*
* Initialize things to make the compiler happy; they're not required.
*/
n = 0;
new_current = 0;
/*
* Set up.
*/
labels = 0;
done = ISC_FALSE;
ndata = isc_buffer_used(target);
nused = 0;
seen_pointer = ISC_FALSE;
/*
* Find the maximum number of uncompressed target name
* bytes we are willing to generate. This is the smaller
* of the available target buffer length and the
* maximum legal domain name length (255).
*/
nmax = isc_buffer_availablelength(target);
if (nmax > DNS_NAME_MAXWIRE)
nmax = DNS_NAME_MAXWIRE;
cdata = isc_buffer_current(source);
cused = 0;
current = source->current;
biggest_pointer = current;
/*
* Note: The following code is not optimized for speed, but
* rather for correctness. Speed will be addressed in the future.
*/
while (current < source->active && !done) {
c = *cdata++;
current++;
if (!seen_pointer)
cused++;
switch (state) {
case fw_start:
if (c < 64) {
offsets[labels] = nused;
labels++;
if (nused + c + 1 > nmax)
goto full;
nused += c + 1;
*ndata++ = c;
if (c == 0)
done = ISC_TRUE;
n = c;
state = fw_ordinary;
} else if (c >= 128 && c < 192) {
/*
* 14 bit local compression pointer.
* Local compression is no longer an
* IETF draft.
*/
return (DNS_R_BADLABELTYPE);
} else if (c >= 192) {
/*
* Ordinary 14-bit pointer.
*/
if ((dctx->allowed & DNS_COMPRESS_GLOBAL14) ==
0)
return (DNS_R_DISALLOWED);
new_current = c & 0x3F;
state = fw_newcurrent;
} else
return (DNS_R_BADLABELTYPE);
break;
case fw_ordinary:
if (downcase)
c = maptolower[c];
*ndata++ = c;
n--;
if (n == 0)
state = fw_start;
break;
case fw_newcurrent:
new_current *= 256;
new_current += c;
if (new_current >= biggest_pointer)
return (DNS_R_BADPOINTER);
biggest_pointer = new_current;
current = new_current;
cdata = (unsigned char *)source->base + current;
seen_pointer = ISC_TRUE;
state = fw_start;
break;
default:
FATAL_ERROR(__FILE__, __LINE__,
"Unknown state %d", state);
/* Does not return. */
}
}
if (!done)
return (ISC_R_UNEXPECTEDEND);
name->ndata = (unsigned char *)target->base + target->used;
name->labels = labels;
name->length = nused;
name->attributes |= DNS_NAMEATTR_ABSOLUTE;
isc_buffer_forward(source, cused);
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
full:
if (nmax == DNS_NAME_MAXWIRE)
/*
* The name did not fit even though we had a buffer
* big enough to fit a maximum-length name.
*/
return (DNS_R_NAMETOOLONG);
else
/*
* The name might fit if only the caller could give us a
* big enough buffer.
*/
return (ISC_R_NOSPACE);
}
isc_result_t
dns_name_towire(const dns_name_t *name, dns_compress_t *cctx,
isc_buffer_t *target)
{
unsigned int methods;
isc_uint16_t offset;
dns_name_t gp; /* Global compression prefix */
isc_boolean_t gf; /* Global compression target found */
isc_uint16_t go; /* Global compression offset */
dns_offsets_t clo;
dns_name_t clname;
/*
* Convert 'name' into wire format, compressing it as specified by the
* compression context 'cctx', and storing the result in 'target'.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(cctx != NULL);
REQUIRE(ISC_BUFFER_VALID(target));
/*
* If 'name' doesn't have an offsets table, make a clone which
* has one.
*/
if (name->offsets == NULL) {
#if defined(__clang__) && \
( __clang_major__ < 3 || (__clang_major__ == 3 && __clang_minor__ < 2))
memset(&clname, 0, sizeof(clname));
#endif
DNS_NAME_INIT(&clname, clo);
dns_name_clone(name, &clname);
name = &clname;
}
DNS_NAME_INIT(&gp, NULL);
offset = target->used; /*XXX*/
methods = dns_compress_getmethods(cctx);
if ((name->attributes & DNS_NAMEATTR_NOCOMPRESS) == 0 &&
(methods & DNS_COMPRESS_GLOBAL14) != 0)
gf = dns_compress_findglobal(cctx, name, &gp, &go);
else
gf = ISC_FALSE;
/*
* If the offset is too high for 14 bit global compression, we're
* out of luck.
*/
if (gf && go >= 0x4000)
gf = ISC_FALSE;
/*
* Will the compression pointer reduce the message size?
*/
if (gf && (gp.length + 2) >= name->length)
gf = ISC_FALSE;
if (gf) {
if (target->length - target->used < gp.length)
return (ISC_R_NOSPACE);
(void)memmove((unsigned char *)target->base + target->used,
gp.ndata, (size_t)gp.length);
isc_buffer_add(target, gp.length);
go |= 0xc000;
if (target->length - target->used < 2)
return (ISC_R_NOSPACE);
isc_buffer_putuint16(target, go);
if (gp.length != 0)
dns_compress_add(cctx, name, &gp, offset);
} else {
if (target->length - target->used < name->length)
return (ISC_R_NOSPACE);
(void)memmove((unsigned char *)target->base + target->used,
name->ndata, (size_t)name->length);
isc_buffer_add(target, name->length);
dns_compress_add(cctx, name, name, offset);
}
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_concatenate(dns_name_t *prefix, dns_name_t *suffix, dns_name_t *name,
isc_buffer_t *target)
{
unsigned char *ndata, *offsets;
unsigned int nrem, labels, prefix_length, length;
isc_boolean_t copy_prefix = ISC_TRUE;
isc_boolean_t copy_suffix = ISC_TRUE;
isc_boolean_t absolute = ISC_FALSE;
dns_name_t tmp_name;
dns_offsets_t odata;
/*
* Concatenate 'prefix' and 'suffix'.
*/
REQUIRE(prefix == NULL || VALID_NAME(prefix));
REQUIRE(suffix == NULL || VALID_NAME(suffix));
REQUIRE(name == NULL || VALID_NAME(name));
REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
(target == NULL && name != NULL && ISC_BUFFER_VALID(name->buffer)));
if (prefix == NULL || prefix->labels == 0)
copy_prefix = ISC_FALSE;
if (suffix == NULL || suffix->labels == 0)
copy_suffix = ISC_FALSE;
if (copy_prefix &&
(prefix->attributes & DNS_NAMEATTR_ABSOLUTE) != 0) {
absolute = ISC_TRUE;
REQUIRE(!copy_suffix);
}
if (name == NULL) {
DNS_NAME_INIT(&tmp_name, odata);
name = &tmp_name;
}
if (target == NULL) {
INSIST(name->buffer != NULL);
target = name->buffer;
isc_buffer_clear(name->buffer);
}
REQUIRE(BINDABLE(name));
/*
* Set up.
*/
nrem = target->length - target->used;
ndata = (unsigned char *)target->base + target->used;
if (nrem > DNS_NAME_MAXWIRE)
nrem = DNS_NAME_MAXWIRE;
length = 0;
prefix_length = 0;
labels = 0;
if (copy_prefix) {
prefix_length = prefix->length;
length += prefix_length;
labels += prefix->labels;
}
if (copy_suffix) {
length += suffix->length;
labels += suffix->labels;
}
if (length > DNS_NAME_MAXWIRE) {
MAKE_EMPTY(name);
return (DNS_R_NAMETOOLONG);
}
if (length > nrem) {
MAKE_EMPTY(name);
return (ISC_R_NOSPACE);
}
if (copy_suffix) {
if ((suffix->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
absolute = ISC_TRUE;
memmove(ndata + prefix_length, suffix->ndata, suffix->length);
}
/*
* If 'prefix' and 'name' are the same object, and the object has
* a dedicated buffer, and we're using it, then we don't have to
* copy anything.
*/
if (copy_prefix && (prefix != name || prefix->buffer != target))
memmove(ndata, prefix->ndata, prefix_length);
name->ndata = ndata;
name->labels = labels;
name->length = length;
if (absolute)
name->attributes = DNS_NAMEATTR_ABSOLUTE;
else
name->attributes = 0;
if (name->labels > 0 && name->offsets != NULL) {
INIT_OFFSETS(name, offsets, odata);
set_offsets(name, offsets, NULL);
}
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
}
void
dns_name_split(dns_name_t *name, unsigned int suffixlabels,
dns_name_t *prefix, dns_name_t *suffix)
{
unsigned int splitlabel;
REQUIRE(VALID_NAME(name));
REQUIRE(suffixlabels > 0);
REQUIRE(suffixlabels < name->labels);
REQUIRE(prefix != NULL || suffix != NULL);
REQUIRE(prefix == NULL ||
(VALID_NAME(prefix) &&
BINDABLE(prefix)));
REQUIRE(suffix == NULL ||
(VALID_NAME(suffix) &&
BINDABLE(suffix)));
splitlabel = name->labels - suffixlabels;
if (prefix != NULL)
dns_name_getlabelsequence(name, 0, splitlabel, prefix);
if (suffix != NULL)
dns_name_getlabelsequence(name, splitlabel,
suffixlabels, suffix);
return;
}
isc_result_t
dns_name_dup(const dns_name_t *source, isc_mem_t *mctx,
dns_name_t *target)
{
/*
* Make 'target' a dynamically allocated copy of 'source'.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(source->length > 0);
REQUIRE(VALID_NAME(target));
REQUIRE(BINDABLE(target));
/*
* Make 'target' empty in case of failure.
*/
MAKE_EMPTY(target);
target->ndata = isc_mem_get(mctx, source->length);
if (target->ndata == NULL)
return (ISC_R_NOMEMORY);
memmove(target->ndata, source->ndata, source->length);
target->length = source->length;
target->labels = source->labels;
target->attributes = DNS_NAMEATTR_DYNAMIC;
if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
target->attributes |= DNS_NAMEATTR_ABSOLUTE;
if (target->offsets != NULL) {
if (source->offsets != NULL)
memmove(target->offsets, source->offsets,
source->labels);
else
set_offsets(target, target->offsets, NULL);
}
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_dupwithoffsets(dns_name_t *source, isc_mem_t *mctx,
dns_name_t *target)
{
/*
* Make 'target' a read-only dynamically allocated copy of 'source'.
* 'target' will also have a dynamically allocated offsets table.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(source->length > 0);
REQUIRE(VALID_NAME(target));
REQUIRE(BINDABLE(target));
REQUIRE(target->offsets == NULL);
/*
* Make 'target' empty in case of failure.
*/
MAKE_EMPTY(target);
target->ndata = isc_mem_get(mctx, source->length + source->labels);
if (target->ndata == NULL)
return (ISC_R_NOMEMORY);
memmove(target->ndata, source->ndata, source->length);
target->length = source->length;
target->labels = source->labels;
target->attributes = DNS_NAMEATTR_DYNAMIC | DNS_NAMEATTR_DYNOFFSETS |
DNS_NAMEATTR_READONLY;
if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
target->attributes |= DNS_NAMEATTR_ABSOLUTE;
target->offsets = target->ndata + source->length;
if (source->offsets != NULL)
memmove(target->offsets, source->offsets, source->labels);
else
set_offsets(target, target->offsets, NULL);
return (ISC_R_SUCCESS);
}
void
dns_name_free(dns_name_t *name, isc_mem_t *mctx) {
size_t size;
/*
* Free 'name'.
*/
REQUIRE(VALID_NAME(name));
REQUIRE((name->attributes & DNS_NAMEATTR_DYNAMIC) != 0);
size = name->length;
if ((name->attributes & DNS_NAMEATTR_DYNOFFSETS) != 0)
size += name->labels;
isc_mem_put(mctx, name->ndata, size);
dns_name_invalidate(name);
}
isc_result_t
dns_name_digest(dns_name_t *name, dns_digestfunc_t digest, void *arg) {
dns_name_t downname;
unsigned char data[256];
isc_buffer_t buffer;
isc_result_t result;
isc_region_t r;
/*
* Send 'name' in DNSSEC canonical form to 'digest'.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(digest != NULL);
#if defined(__clang__) && \
( __clang_major__ < 3 || (__clang_major__ == 3 && __clang_minor__ < 2))
memset(&downname, 0, sizeof(downname));
#endif
DNS_NAME_INIT(&downname, NULL);
isc_buffer_init(&buffer, data, sizeof(data));
result = dns_name_downcase(name, &downname, &buffer);
if (result != ISC_R_SUCCESS)
return (result);
isc_buffer_usedregion(&buffer, &r);
return ((digest)(arg, &r));
}
isc_boolean_t
dns_name_dynamic(dns_name_t *name) {
REQUIRE(VALID_NAME(name));
/*
* Returns whether there is dynamic memory associated with this name.
*/
return ((name->attributes & DNS_NAMEATTR_DYNAMIC) != 0 ?
ISC_TRUE : ISC_FALSE);
}
isc_result_t
dns_name_print(dns_name_t *name, FILE *stream) {
isc_result_t result;
isc_buffer_t b;
isc_region_t r;
char t[1024];
/*
* Print 'name' on 'stream'.
*/
REQUIRE(VALID_NAME(name));
isc_buffer_init(&b, t, sizeof(t));
result = dns_name_totext(name, ISC_FALSE, &b);
if (result != ISC_R_SUCCESS)
return (result);
isc_buffer_usedregion(&b, &r);
fprintf(stream, "%.*s", (int)r.length, (char *)r.base);
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_settotextfilter(dns_name_totextfilter_t proc) {
#ifdef ISC_PLATFORM_USETHREADS
isc_result_t result;
dns_name_totextfilter_t *mem;
int res;
result = totext_filter_proc_key_init();
if (result != ISC_R_SUCCESS)
return (result);
/*
* If we already have been here set / clear as appropriate.
* Otherwise allocate memory.
*/
mem = isc_thread_key_getspecific(totext_filter_proc_key);
if (mem != NULL && proc != NULL) {
*mem = proc;
return (ISC_R_SUCCESS);
}
if (proc == NULL) {
isc_mem_put(thread_key_mctx, mem, sizeof(*mem));
res = isc_thread_key_setspecific(totext_filter_proc_key, NULL);
if (res != 0)
result = ISC_R_UNEXPECTED;
return (result);
}
mem = isc_mem_get(thread_key_mctx, sizeof(*mem));
if (mem == NULL)
return (ISC_R_NOMEMORY);
*mem = proc;
if (isc_thread_key_setspecific(totext_filter_proc_key, mem) != 0) {
isc_mem_put(thread_key_mctx, mem, sizeof(*mem));
result = ISC_R_UNEXPECTED;
}
return (result);
#else
totext_filter_proc = proc;
return (ISC_R_SUCCESS);
#endif
}
void
dns_name_format(const dns_name_t *name, char *cp, unsigned int size) {
isc_result_t result;
isc_buffer_t buf;
REQUIRE(size > 0);
/*
* Leave room for null termination after buffer.
*/
isc_buffer_init(&buf, cp, size - 1);
result = dns_name_totext(name, ISC_TRUE, &buf);
if (result == ISC_R_SUCCESS) {
/*
* Null terminate.
*/
isc_region_t r;
isc_buffer_usedregion(&buf, &r);
((char *) r.base)[r.length] = '\0';
} else
snprintf(cp, size, "<unknown>");
}
/*
* dns_name_tostring() -- similar to dns_name_format() but allocates its own
* memory.
*/
isc_result_t
dns_name_tostring(dns_name_t *name, char **target, isc_mem_t *mctx) {
isc_result_t result;
isc_buffer_t buf;
isc_region_t reg;
char *p, txt[DNS_NAME_FORMATSIZE];
REQUIRE(VALID_NAME(name));
REQUIRE(target != NULL && *target == NULL);
isc_buffer_init(&buf, txt, sizeof(txt));
result = dns_name_totext(name, ISC_FALSE, &buf);
if (result != ISC_R_SUCCESS)
return (result);
isc_buffer_usedregion(&buf, &reg);
p = isc_mem_allocate(mctx, reg.length + 1);
if (p == NULL)
return (ISC_R_NOMEMORY);
memmove(p, (char *) reg.base, (int) reg.length);
p[reg.length] = '\0';
*target = p;
return (ISC_R_SUCCESS);
}
/*
* dns_name_fromstring() -- convert directly from a string to a name,
* allocating memory as needed
*/
isc_result_t
dns_name_fromstring(dns_name_t *target, const char *src, unsigned int options,
isc_mem_t *mctx)
{
return (dns_name_fromstring2(target, src, dns_rootname, options, mctx));
}
isc_result_t
dns_name_fromstring2(dns_name_t *target, const char *src,
const dns_name_t *origin, unsigned int options,
isc_mem_t *mctx)
{
isc_result_t result;
isc_buffer_t buf;
dns_fixedname_t fn;
dns_name_t *name;
REQUIRE(src != NULL);
isc_buffer_constinit(&buf, src, strlen(src));
isc_buffer_add(&buf, strlen(src));
if (BINDABLE(target) && target->buffer != NULL)
name = target;
else {
dns_fixedname_init(&fn);
name = dns_fixedname_name(&fn);
}
result = dns_name_fromtext(name, &buf, origin, options, NULL);
if (result != ISC_R_SUCCESS)
return (result);
if (name != target)
result = dns_name_dupwithoffsets(name, mctx, target);
return (result);
}
isc_result_t
dns_name_copy(const dns_name_t *source, dns_name_t *dest, isc_buffer_t *target) {
unsigned char *ndata;
/*
* Make dest a copy of source.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(VALID_NAME(dest));
REQUIRE(target != NULL || dest->buffer != NULL);
if (target == NULL) {
target = dest->buffer;
isc_buffer_clear(dest->buffer);
}
REQUIRE(BINDABLE(dest));
/*
* Set up.
*/
if (target->length - target->used < source->length)
return (ISC_R_NOSPACE);
ndata = (unsigned char *)target->base + target->used;
dest->ndata = target->base;
memmove(ndata, source->ndata, source->length);
dest->ndata = ndata;
dest->labels = source->labels;
dest->length = source->length;
if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
dest->attributes = DNS_NAMEATTR_ABSOLUTE;
else
dest->attributes = 0;
if (dest->labels > 0 && dest->offsets != NULL) {
if (source->offsets != NULL)
memmove(dest->offsets, source->offsets, source->labels);
else
set_offsets(dest, dest->offsets, NULL);
}
isc_buffer_add(target, dest->length);
return (ISC_R_SUCCESS);
}
void
dns_name_destroy(void) {
#ifdef ISC_PLATFORM_USETHREADS
RUNTIME_CHECK(isc_once_do(&once, thread_key_mutex_init)
== ISC_R_SUCCESS);
LOCK(&thread_key_mutex);
if (thread_key_initialized) {
isc_mem_detach(&thread_key_mctx);
isc_thread_key_delete(totext_filter_proc_key);
thread_key_initialized = 0;
}
UNLOCK(&thread_key_mutex);
#endif
}
/*
* Service Discovery Prefixes RFC 6763.
*/
static unsigned char b_dns_sd_udp_data[] = "\001b\007_dns-sd\004_udp";
static unsigned char b_dns_sd_udp_offsets[] = { 0, 2, 10 };
static unsigned char db_dns_sd_udp_data[] = "\002db\007_dns-sd\004_udp";
static unsigned char db_dns_sd_udp_offsets[] = { 0, 3, 11 };
static unsigned char r_dns_sd_udp_data[] = "\001r\007_dns-sd\004_udp";
static unsigned char r_dns_sd_udp_offsets[] = { 0, 2, 10 };
static unsigned char dr_dns_sd_udp_data[] = "\002dr\007_dns-sd\004_udp";
static unsigned char dr_dns_sd_udp_offsets[] = { 0, 3, 11 };
static unsigned char lb_dns_sd_udp_data[] = "\002lb\007_dns-sd\004_udp";
static unsigned char lb_dns_sd_udp_offsets[] = { 0, 3, 11 };
static const dns_name_t dns_sd[] = {
{
DNS_NAME_MAGIC,
b_dns_sd_udp_data, 15, 3,
DNS_NAMEATTR_READONLY,
b_dns_sd_udp_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
},
{
DNS_NAME_MAGIC,
db_dns_sd_udp_data, 16, 3,
DNS_NAMEATTR_READONLY,
db_dns_sd_udp_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
},
{
DNS_NAME_MAGIC,
r_dns_sd_udp_data, 15, 3,
DNS_NAMEATTR_READONLY,
r_dns_sd_udp_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
},
{
DNS_NAME_MAGIC,
dr_dns_sd_udp_data, 16, 3,
DNS_NAMEATTR_READONLY,
dr_dns_sd_udp_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
},
{
DNS_NAME_MAGIC,
lb_dns_sd_udp_data, 16, 3,
DNS_NAMEATTR_READONLY,
lb_dns_sd_udp_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
}
};
isc_boolean_t
dns_name_isdnssd(const dns_name_t *name) {
size_t i;
dns_name_t prefix;
if (dns_name_countlabels(name) > 3U) {
dns_name_init(&prefix, NULL);
dns_name_getlabelsequence(name, 0, 3, &prefix);
for (i = 0; i < (sizeof(dns_sd)/sizeof(dns_sd[0])); i++)
if (dns_name_equal(&prefix, &dns_sd[i]))
return (ISC_TRUE);
}
return (ISC_FALSE);
}