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bind9/lib/dns/name.c
David Lawrence 6d12fdf966 Megacommit of many files. 
Mostly, several functions that take pointers as arguments, almost
always char * pointers, had those pointers qualified with "const".
Those that returned pointers to previously const-qualified arguments
had their return values qualified as const.  Some structure members
were qualified as const to retain that attribute from the variables
from which they were assigned.

The macro DE_CONST is used to deal with a handful of very special
places where something is qualified as const but really needs to have
its const qualifier removed.

rdata.c now defines macros for the prototypes of the basic rdata functions,
and all of the lib/dns/rdata/**/*.c files now use them.

Some minor integer-compatibility issues.  (IE, ~0x03 is a signed int,
so assigning it to an unsigned int should use a cast.  The type of an
enum member is int, so there are some conversion issues there, too.)

A pointers-to-function should not be cast to a pointer-to-object.

Variables should not be named for C reserved identifiers.

One or two set-but-not-used variables removed.

Minor other ISC style cleanups.
2000-06-01 18:26:56 +00:00

3083 lines
69 KiB
C
Raw Blame History

/*
* Copyright (C) 1998, 1999, 2000 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS
* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
* CONSORTIUM 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.
*/
#include <config.h>
#include <ctype.h>
#include <isc/buffer.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/string.h>
#include <isc/util.h>
#include <dns/result.h>
#include <dns/name.h>
#include <dns/compress.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_bitstring,
ft_binary,
ft_octal,
ft_hex,
ft_dottedquad,
ft_dqdecimal,
ft_maybeslash,
ft_finishbitstring,
ft_bitlength,
ft_eatdot,
ft_at
} ft_state;
typedef enum {
fw_start = 0,
fw_ordinary,
fw_copy,
fw_bitstring,
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 char hexdigits[16] = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
};
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)
/*
* This silliness is to avoid warnings about the const attribute of a string
* being discarded, as can happen (depending on the compiler and flags)
* when name.ndata or name.offsets is assigned to via a string literal.
* Unfortunately, gcc -Wwrite-strings produces incorrect warnings for
* assigning a const string to the ndata or offsets members in
* "const struct dns_name root", which (at least according to the ANSI
* Draft dated August 3, 1998) should have the effect of declaring all
* members of the struct as const.
*/
struct dns_constname {
dns_name_t name;
char const_ndata[2];
char const_offsets[1];
};
static struct dns_constname root = {
{
DNS_NAME_MAGIC,
root.const_ndata, 1, 1,
DNS_NAMEATTR_READONLY | DNS_NAMEATTR_ABSOLUTE,
root.const_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
},
{ '\0', '\0' }, /* const_ndata */
{ '\0' } /* const_offsets */
};
/* XXXDCL make const? */
dns_name_t *dns_rootname = &root.name;
static struct dns_constname wild = {
{
DNS_NAME_MAGIC,
wild.const_ndata, 2, 1,
DNS_NAMEATTR_READONLY,
wild.const_offsets, NULL,
{(void *)-1, (void *)-1},
{NULL, NULL}
},
{ '\001', '*' }, /* const_ndata */
{ '\0' } /* const_offsets */
};
/* XXXDCL make const? */
dns_name_t *dns_wildcardname = &wild.name;
static void
set_offsets(const dns_name_t *name, unsigned char *offsets,
dns_name_t *set_name);
static void
compact(dns_name_t *name, unsigned char *offsets);
/*
* Yes, get_bit and set_bit are lame. We define them here so they can
* be inlined by smart compilers.
*/
static inline unsigned int
get_bit(unsigned char *array, unsigned int idx) {
unsigned int byte, shift;
byte = array[idx / 8];
shift = 7 - (idx % 8);
return ((byte >> shift) & 0x01);
}
static inline void
set_bit(unsigned char *array, unsigned int idx, unsigned int bit) {
unsigned int shift, mask;
shift = 7 - (idx % 8);
mask = 1 << shift;
if (bit != 0)
array[idx / 8] |= mask;
else
array[idx / 8] &= (~mask & 0xFF);
}
dns_labeltype_t
dns_label_type(dns_label_t *label) {
/*
* Get the type of 'label'.
*/
REQUIRE(label != NULL);
REQUIRE(label->length > 0);
REQUIRE(label->base[0] <= 63 ||
label->base[0] == DNS_LABELTYPE_BITSTRING);
if (label->base[0] <= 63)
return (dns_labeltype_ordinary);
else
return (dns_labeltype_bitstring);
}
unsigned int
dns_label_countbits(dns_label_t *label) {
unsigned int count;
/*
* The number of bits in a bitstring label.
*/
REQUIRE(label != NULL);
REQUIRE(label->length > 2);
REQUIRE(label->base[0] == DNS_LABELTYPE_BITSTRING);
count = label->base[1];
if (count == 0)
count = 256;
return (count);
}
dns_bitlabel_t
dns_label_getbit(dns_label_t *label, unsigned int n) {
unsigned int count, bit;
/*
* The 'n'th most significant bit of 'label'.
*
* Notes:
* Numbering starts at 0.
*/
REQUIRE(label != NULL);
REQUIRE(label->length > 2);
REQUIRE(label->base[0] == DNS_LABELTYPE_BITSTRING);
count = label->base[1];
if (count == 0)
count = 256;
REQUIRE(n < count);
bit = get_bit(&label->base[2], n);
if (bit == 0)
return (dns_bitlabel_0);
return (dns_bitlabel_1);
}
void
dns_name_init(dns_name_t *name, unsigned char *offsets) {
/*
* Initialize 'name'.
*/
name->magic = DNS_NAME_MAGIC;
name->ndata = NULL;
name->length = 0;
name->labels = 0;
name->attributes = 0;
name->offsets = offsets;
name->buffer = NULL;
ISC_LINK_INIT(name, link);
ISC_LIST_INIT(name->list);
}
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 binary 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));
REQUIRE(name->labels > 0);
if ((name->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
return (ISC_TRUE);
return (ISC_FALSE);
}
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_requiresedns(const dns_name_t *name) {
unsigned int count, nrem;
unsigned char *ndata;
isc_boolean_t requiresedns = ISC_FALSE;
/*
* Does 'name' require EDNS for transmission?
*/
REQUIRE(VALID_NAME(name));
REQUIRE(name->labels > 0);
ndata = name->ndata;
nrem = name->length;
while (nrem > 0) {
count = *ndata++;
nrem--;
if (count == 0)
break;
if (count > 63) {
INSIST(count == DNS_LABELTYPE_BITSTRING);
requiresedns = ISC_TRUE;
break;
}
INSIST(nrem >= count);
nrem -= count;
ndata += count;
}
return (requiresedns);
}
unsigned int
dns_name_hash(dns_name_t *name, isc_boolean_t case_sensitive) {
unsigned int length;
const unsigned char *s;
unsigned int h = 0;
unsigned int g;
unsigned char c;
/*
* Provide a hash value for 'name'.
*/
REQUIRE(VALID_NAME(name));
if (name->labels == 0)
return (0);
length = name->length;
if (length > 16)
length = 16;
/*
* P. J. Weinberger's hash function, adapted from p. 436 of
* _Compilers: Principles, Techniques, and Tools_, Aho, Sethi
* and Ullman, Addison-Wesley, 1986, ISBN 0-201-10088-6.
*/
s = name->ndata;
if (case_sensitive) {
while (length > 0) {
h = ( h << 4 ) + *s;
if ((g = ( h & 0xf0000000 )) != 0) {
h = h ^ (g >> 24);
h = h ^ g;
}
s++;
length--;
}
} else {
while (length > 0) {
c = maptolower[*s];
h = ( h << 4 ) + c;
if ((g = ( h & 0xf0000000 )) != 0) {
h = h ^ (g >> 24);
h = h ^ g;
}
s++;
length--;
}
}
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 *nbitsp)
{
unsigned int l1, l2, l, count1, count2, count;
unsigned int b1, b2, n, nlabels, nbits;
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(name1->labels > 0);
REQUIRE(VALID_NAME(name2));
REQUIRE(name2->labels > 0);
REQUIRE(orderp != NULL);
REQUIRE(nlabelsp != NULL);
REQUIRE(nbitsp != 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;
nbits = 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++;
if (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++;
} else if (count1 == DNS_LABELTYPE_BITSTRING && count2 <= 63) {
if (count2 == 0)
*orderp = 1;
else
*orderp = -1;
goto done;
} else if (count2 == DNS_LABELTYPE_BITSTRING && count1 <= 63) {
if (count1 == 0)
*orderp = -1;
else
*orderp = 1;
goto done;
} else {
INSIST(count1 == DNS_LABELTYPE_BITSTRING &&
count2 == DNS_LABELTYPE_BITSTRING);
count1 = *label1++;
if (count1 == 0)
count1 = 256;
count2 = *label2++;
if (count2 == 0)
count2 = 256;
if (count1 < count2) {
cdiff = -1;
count = count1;
} else {
count = count2;
if (count1 > count2)
cdiff = 1;
else
cdiff = 0;
}
/* Yes, this loop is really slow! */
for (n = 0; n < count; n++) {
b1 = get_bit(label1, n);
b2 = get_bit(label2, n);
if (b1 < b2) {
*orderp = -1;
goto done;
} else if (b1 > b2) {
*orderp = 1;
goto done;
}
if (nbits == 0)
nlabels++;
nbits++;
}
if (cdiff != 0) {
/*
* If we're here, then we have two bitstrings
* of differing length.
*
* If the name with the shorter bitstring
* has any labels, then it must be greater
* than the longer bitstring. This is a bit
* counterintuitive. If the name with the
* shorter bitstring has any more labels, then
* the next label must be an ordinary label.
* It can't be a bitstring label because if it
* were, then there would be room for it in
* the current bitstring label (since all
* bitstrings are canonicalized). Since
* there's at least one more bit in the
* name with the longer bitstring, and since
* a bitlabel sorts before any ordinary label,
* the name with the longer bitstring must
* be lexically before the one with the shorter
* bitstring.
*
* On the other hand, if there are no more
* labels in the name with the shorter
* bitstring, then that name contains the
* other name.
*/
namereln = dns_namereln_commonancestor;
if (cdiff < 0) {
if (l1 > 0)
*orderp = 1;
else {
*orderp = -1;
namereln =
dns_namereln_contains;
}
} else {
if (l2 > 0)
*orderp = -1;
else {
*orderp = 1;
namereln =
dns_namereln_subdomain;
}
}
goto done;
}
nbits = 0;
}
}
*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;
*nbitsp = nbits;
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, nbits;
/*
* 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, &nbits);
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->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);
if (count <= 63) {
while (count > 0) {
count--;
c = maptolower[*label1++];
if (c != maptolower[*label2++])
return (ISC_FALSE);
}
} else {
INSIST(count == DNS_LABELTYPE_BITSTRING);
count = *label1++;
if (count != *label2++)
return (ISC_FALSE);
if (count == 0)
count = 256;
/*
* Number of bytes.
*/
count = (count + 7) / 8;
while (count > 0) {
count--;
c = *label1++;
if (c != *label2++)
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++;
if (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);
}
} else if (count1 == DNS_LABELTYPE_BITSTRING && count2 <= 63) {
return (1);
} else if (count2 == DNS_LABELTYPE_BITSTRING && count1 <= 63) {
return (-1);
} else {
INSIST(count1 == DNS_LABELTYPE_BITSTRING &&
count2 == DNS_LABELTYPE_BITSTRING);
count2 = *label2++;
count1 = *label1++;
if (count1 != count2)
return ((count1 < count2) ? -1 : 1);
if (count1 == 0)
count1 = 256;
if (count2 == 0)
count2 = 256;
/* number of bytes */
count = (count1 + 7) / 8;
while (count > 0) {
count--;
c1 = *label1++;
c2 = *label2++;
if (c1 != c2)
return ((c1 < c2) ? -1 : 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, nbits;
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,
&nbits);
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, nbits, 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));
dns_name_init(&tname, NULL);
dns_name_getlabelsequence(wname, 1, labels - 1, &tname);
if (dns_name_fullcompare(name, &tname, &order, &nlabels, &nbits) ==
dns_namereln_subdomain)
return (ISC_TRUE);
return (ISC_FALSE);
}
unsigned int
dns_name_depth(const dns_name_t *name) {
unsigned int depth, count, nrem, n;
unsigned char *ndata;
/*
* The depth of 'name'.
*/
REQUIRE(VALID_NAME(name));
if (name->labels == 0)
return (0);
depth = 0;
ndata = name->ndata;
nrem = name->length;
while (nrem > 0) {
count = *ndata++;
nrem--;
if (count > 63) {
INSIST(count == DNS_LABELTYPE_BITSTRING);
INSIST(nrem != 0);
n = *ndata++;
nrem--;
if (n == 0)
n = 256;
depth += n;
count = n / 8;
if (n % 8 != 0)
count++;
} else {
depth++;
if (count == 0)
break;
}
INSIST(nrem >= count);
nrem -= count;
ndata += count;
}
return (depth);
}
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;
/*
* Make 'target' refer to the 'n' labels including and following
* 'first' in 'source'.
*/
REQUIRE(VALID_NAME(source));
REQUIRE(VALID_NAME(target));
REQUIRE(source->labels > 0);
REQUIRE(n > 0);
REQUIRE(first < source->labels);
REQUIRE(first + n <= source->labels);
REQUIRE(BINDABLE(target));
SETUP_OFFSETS(source, offsets, odata);
target->ndata = &source->ndata[offsets[first]];
if (first + n == source->labels) {
target->length = source->length - offsets[first];
if ((source->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
target->attributes |= DNS_NAMEATTR_ABSOLUTE;
else
target->attributes &= ~DNS_NAMEATTR_ABSOLUTE;
} else {
target->length = offsets[first + n] - offsets[first];
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(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)
memcpy(target->offsets, source->offsets,
source->labels);
else
set_offsets(target, target->offsets, NULL);
}
}
void
dns_name_fromregion(dns_name_t *name, 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 > 255)
len = 255;
memcpy(r2.base, r->base, len);
name->ndata = r2.base;
name->length = len;
} else {
name->ndata = r->base;
name->length = (r->length <= 255) ? r->length : 255;
}
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);
r->base = name->ndata;
r->length = name->length;
}
isc_result_t
dns_name_fromtext(dns_name_t *name, isc_buffer_t *source,
dns_name_t *origin, isc_boolean_t downcase,
isc_buffer_t *target)
{
unsigned char *ndata, *label;
char *tdata;
char c;
ft_state state, kind;
unsigned int value, count, tbcount, bitlength, maxlength;
unsigned int n1, n2, vlen, tlen, nrem, nused, digits, labels, tused;
isc_boolean_t done, saw_bitstring;
unsigned char dqchars[4];
unsigned char *offsets;
dns_offsets_t odata;
/*
* 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(isc_buffer_current(source) < isc_buffer_used(source));
REQUIRE((target != NULL && ISC_BUFFER_VALID(target)) ||
(target == NULL && name->buffer != NULL));
if (target == NULL && name->buffer != NULL) {
target = name->buffer;
isc_buffer_clear(target);
}
REQUIRE(BINDABLE(name));
INIT_OFFSETS(name, offsets, odata);
offsets[0] = 0;
/*
* Initialize things to make the compiler happy; they're not required.
*/
n1 = 0;
n2 = 0;
vlen = 0;
label = NULL;
digits = 0;
value = 0;
count = 0;
tbcount = 0;
bitlength = 0;
maxlength = 0;
kind = ft_init;
/*
* 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;
saw_bitstring = ISC_FALSE;
state = ft_init;
while (nrem > 0 && tlen > 0 && !done) {
c = *tdata++;
tlen--;
tused++;
no_read:
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;
}
kind = ft_ordinary;
state = ft_ordinary;
/* 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[(int)c];
*ndata++ = c;
nrem--;
nused++;
}
break;
case ft_initialescape:
if (c == '[') {
saw_bitstring = ISC_TRUE;
kind = ft_bitstring;
state = ft_bitstring;
*label = DNS_LABELTYPE_BITSTRING;
label = ndata;
ndata++;
nrem--;
nused++;
break;
}
kind = ft_ordinary;
state = ft_escape;
/* FALLTHROUGH */
case ft_escape:
if (!isdigit(c & 0xff)) {
if (count >= 63)
return (DNS_R_LABELTOOLONG);
count++;
CONVERTTOASCII(c);
if (downcase)
c = maptolower[(int)c];
*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[(int)c];
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;
case ft_bitstring:
/* count is zero */
tbcount = 0;
value = 0;
if (c == 'b') {
vlen = 8;
maxlength = 256;
kind = ft_binary;
state = ft_binary;
} else if (c == 'o') {
vlen = 8;
maxlength = 256;
kind = ft_octal;
state = ft_octal;
} else if (c == 'x') {
vlen = 8;
maxlength = 256;
kind = ft_hex;
state = ft_hex;
} else if (isdigit(c & 0xff)) {
vlen = 32;
maxlength = 32;
n1 = 0;
n2 = 0;
digits = 0;
kind = ft_dottedquad;
state = ft_dqdecimal;
goto no_read;
} else
return (DNS_R_BADBITSTRING);
break;
case ft_binary:
if (c != '0' && c != '1') {
state = ft_maybeslash;
goto no_read;
}
value <<= 1;
if (c == '1')
value |= 1;
count++;
tbcount++;
if (tbcount > 256)
return (DNS_R_BITSTRINGTOOLONG);
if (count == 8) {
*ndata++ = value;
nrem--;
nused++;
count = 0;
}
break;
case ft_octal:
if (!isdigit(c & 0xff) || c == '9' || c == '8') {
state = ft_maybeslash;
goto no_read;
}
value <<= 3;
value += digitvalue[(int)c];
count += 3;
tbcount += 3;
/*
* The total bit count is tested against 258 instead
* of 256 because of the possibility that the bitstring
* label is exactly 256 bits long; on the last octal
* digit (which must be 4) tbcount is incremented
* from 255 to 258. This case is adequately handled
* later.
*/
if (tbcount > 258)
return (DNS_R_BITSTRINGTOOLONG);
if (count == 8) {
*ndata++ = value;
nrem--;
nused++;
count = 0;
} else if (count == 9) {
*ndata++ = (value >> 1);
nrem--;
nused++;
value &= 1;
count = 1;
} else if (count == 10) {
*ndata++ = (value >> 2);
nrem--;
nused++;
value &= 3;
count = 2;
}
break;
case ft_hex:
if (!isxdigit(c & 0xff)) {
state = ft_maybeslash;
goto no_read;
}
value <<= 4;
value += digitvalue[(int)c];
count += 4;
tbcount += 4;
if (tbcount > 256)
return (DNS_R_BITSTRINGTOOLONG);
if (count == 8) {
*ndata++ = value;
nrem--;
nused++;
count = 0;
}
break;
case ft_dottedquad:
if (c != '.' && n1 < 3)
return (DNS_R_BADDOTTEDQUAD);
dqchars[n1] = value;
n2 *= 256;
n2 += value;
n1++;
if (n1 == 4) {
tbcount = 32;
value = n2;
state = ft_maybeslash;
goto no_read;
}
value = 0;
digits = 0;
state = ft_dqdecimal;
break;
case ft_dqdecimal:
if (!isdigit(c & 0xff)) {
if (digits == 0 || value > 255)
return (DNS_R_BADDOTTEDQUAD);
state = ft_dottedquad;
goto no_read;
}
digits++;
if (digits > 3)
return (DNS_R_BADDOTTEDQUAD);
value *= 10;
value += digitvalue[(int)c];
break;
case ft_maybeslash:
bitlength = 0;
if (c == '/') {
state = ft_bitlength;
break;
}
/* FALLTHROUGH */
case ft_finishbitstring:
if (c == ']') {
if (tbcount == 0)
return (DNS_R_BADBITSTRING);
if (count > 0) {
n1 = count % 8;
if (n1 != 0)
value <<= (8 - n1);
}
if (bitlength != 0) {
if (bitlength > tbcount)
return (DNS_R_BADBITSTRING);
if (kind == ft_binary &&
bitlength != tbcount) {
return (DNS_R_BADBITSTRING);
} else if (kind == ft_octal) {
/*
* Figure out correct number
* of octal digits for the
* bitlength, and compare to
* what was given.
*/
n1 = bitlength / 3;
if (bitlength % 3 != 0)
n1++;
n2 = tbcount / 3;
/* tbcount % 3 == 0 */
if (n1 != n2)
return (DNS_R_BADBITSTRING);
/*
* Check that no bits extend
* past the end of the last
* byte that is included in
* the bitlength. Example:
* \[o036/8] == \[b00001111],
* which fits into just one
* byte, but the three octal
* digits actually specified
* two bytes worth of data,
* 9 bits, before the bitlength
* limited it back to one byte.
*
* n1 is the number of bytes
* necessary for the bitlength.
* n2 is the number of bytes
* encompassed by the octal
* digits. If they are not
* equal, then "value" holds
* the excess bits, which
* must be zero. If the bits
* are zero, then "count" is
* zero'ed to prevent the
* addition of another byte
* below.
*/
n1 = bitlength - 1 / 8;
n2 = tbcount - 1 / 8;
if (n1 != n2) {
if (value != 0)
return
(DNS_R_BADBITSTRING);
else
count = 0;
}
} else if (kind == ft_hex) {
/*
* Figure out correct number
* of hex digits for the
* bitlength, and compare to
* what was given.
*/
n1 = bitlength / 4;
if (bitlength % 4 != 0)
n1++;
n2 = tbcount / 4;
/* tbcount % 4 == 0 */
if (n1 != n2)
return (DNS_R_BADBITSTRING);
}
n1 = bitlength % vlen;
if (n1 != 0) {
/*
* Are the pad bits in the
* last 'vlen' bits zero?
*/
if ((value &
~((~0) << (vlen-n1))) != 0)
return (DNS_R_BADBITSTRING);
}
} else if (kind == ft_dottedquad)
bitlength = 32;
else if (tbcount > 256)
/*
* This can happen when an octal
* bitstring label of 86 octal digits
* is specified; tbcount will be 258.
* This is not trapped above because
* the bitstring label might be limited
* by a "/256" modifier.
*/
return (DNS_R_BADBITSTRING);
else
bitlength = tbcount;
if (count > 0) {
*ndata++ = value;
nrem--;
nused++;
}
if (kind == ft_dottedquad) {
n1 = bitlength / 8;
if (bitlength % 8 != 0)
n1++;
if (nrem < n1)
return (ISC_R_NOSPACE);
for (n2 = 0; n2 < n1; n2++) {
*ndata++ = dqchars[n2];
nrem--;
nused++;
}
}
if (bitlength == 256)
*label = 0;
else
*label = bitlength;
labels++;
INSIST(labels <= 127);
offsets[labels] = nused;
} else
return (DNS_R_BADBITSTRING);
state = ft_eatdot;
break;
case ft_bitlength:
if (!isdigit(c & 0xff)) {
if (bitlength == 0)
return (DNS_R_BADBITSTRING);
state = ft_finishbitstring;
goto no_read;
}
bitlength *= 10;
bitlength += digitvalue[(int)c];
if (bitlength > maxlength)
return (DNS_R_BADBITSTRING);
break;
case ft_eatdot:
if (c != '.')
return (DNS_R_BADBITSTRING);
if (tlen == 0) {
labels++;
*ndata++ = 0;
nrem--;
nused++;
done = ISC_TRUE;
}
state = ft_start;
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_eatdot &&
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;
while (n1 > 0) {
n2 = *label++;
if (n2 <= 63) {
*ndata++ = n2;
n1 -= n2 + 1;
nused += n2 + 1;
while (n2 > 0) {
c = *label++;
if (downcase)
c = maptolower[(int)c];
*ndata++ = c;
n2--;
}
} else {
INSIST(n2 == DNS_LABELTYPE_BITSTRING);
*ndata++ = n2;
bitlength = *label++;
*ndata++ = bitlength;
if (bitlength == 0)
bitlength = 256;
n2 = bitlength / 8;
if (bitlength % 8 != 0)
n2++;
n1 -= n2 + 2;
nused += n2 + 2;
while (n2 > 0) {
*ndata++ = *label++;
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;
if (saw_bitstring)
compact(name, offsets);
isc_buffer_forward(source, tused);
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_totext(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 bytes, nibbles;
size_t i, len;
unsigned int labels;
isc_boolean_t saw_root = ISC_FALSE;
char num[4];
/*
* This function assumes the name is in proper uncompressed
* wire format.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(name->labels > 0);
ndata = name->ndata;
nlen = name->length;
labels = name->labels;
tdata = (char *)target->base + target->used;
tlen = target->length - target->used;
trem = tlen;
/* Special handling for root label. */
if (nlen == 1 && labels == 1 && *ndata == 0) {
saw_root = ISC_TRUE;
labels = 0;
nlen = 0;
if (trem == 0)
return (ISC_R_NOSPACE);
*tdata++ = '.';
trem--;
omit_final_dot = ISC_FALSE;
}
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) {
case 0x22: /* '"' */
case 0x2E: /* '.' */
case 0x3B: /* ';' */
case 0x5C: /* '\\' */
/* Special modifiers in zone files. */
case 0x40: /* '@' */
case 0x24: /* '$' */
if (trem < 2)
return (ISC_R_NOSPACE);
*tdata++ = '\\';
CONVERTFROMASCII(c);
*tdata++ = c;
ndata++;
trem -= 2;
nlen--;
break;
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);
sprintf(tdata, "\\%03u",
c);
tdata += 4;
trem -= 4;
ndata++;
nlen--;
}
}
count--;
}
} else if (count == DNS_LABELTYPE_BITSTRING) {
if (trem < 3)
return (ISC_R_NOSPACE);
*tdata++ = '\\';
*tdata++ = '[';
*tdata++ = 'x';
trem -= 3;
INSIST(nlen > 0);
count = *ndata++;
if (count == 0)
count = 256;
nlen--;
len = sprintf(num, "%u", count); /* XXX */
INSIST(len <= 4);
bytes = count / 8;
if (count % 8 != 0)
bytes++;
INSIST(nlen >= bytes);
nibbles = count / 4;
if (count % 4 != 0)
nibbles++;
if (trem < nibbles)
return (ISC_R_NOSPACE);
trem -= nibbles;
nlen -= bytes;
while (nibbles > 0) {
c = *ndata++;
*tdata++ = hexdigits[(c >> 4)];
nibbles--;
if (nibbles != 0) {
*tdata++ = hexdigits[c & 0xf];
i++;
nibbles--;
}
}
if (trem < 2 + len)
return (ISC_R_NOSPACE);
*tdata++ = '/';
for (i = 0; i < len; i++)
*tdata++ = num[i];
*tdata++ = ']';
trem -= 2 + len;
} else {
FATAL_ERROR(__FILE__, __LINE__,
"Unexpected label type %02x", count);
/* Does not return. */
}
/*
* 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);
INSIST(nlen == 0);
if (!saw_root || 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, bytes, 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));
if (target == NULL && name->buffer != 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 if (count == DNS_LABELTYPE_BITSTRING) {
INSIST(nlen > 0);
count = *sndata++;
*ndata++ = count;
if (count == 0)
count = 256;
nlen--;
bytes = count / 8;
if (count % 8 != 0)
bytes++;
INSIST(nlen >= bytes);
nlen -= bytes;
while (bytes > 0) {
*ndata++ = *sndata++;
bytes--;
}
} 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, n;
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++;
if (count <= 63) {
offset += count;
ndata += count;
INSIST(offset <= length);
if (count == 0) {
absolute = ISC_TRUE;
break;
}
} else {
INSIST(count == DNS_LABELTYPE_BITSTRING);
n = *ndata++;
offset++;
if (n == 0)
n = 256;
count = n / 8;
if (n % 8 != 0)
count++;
offset += count;
ndata += count;
INSIST(offset <= length);
}
}
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);
}
static void
compact(dns_name_t *name, unsigned char *offsets) {
unsigned char *head, *curr, *last;
unsigned int count, n, bit;
unsigned int headbits, currbits, tailbits, newbits;
unsigned int headrem, newrem;
unsigned int headindex, currindex, tailindex, newindex;
unsigned char tail[32];
/*
* The caller MUST ensure that all bitstrings are correctly formatted
* and that the offsets table is valid.
*/
again:
memset(tail, 0, sizeof tail);
INSIST(name->labels != 0);
n = name->labels - 1;
while (n > 0) {
head = &name->ndata[offsets[n]];
if (head[0] == DNS_LABELTYPE_BITSTRING && head[1] != 0) {
if (n != 0) {
n--;
curr = &name->ndata[offsets[n]];
if (curr[0] != DNS_LABELTYPE_BITSTRING)
continue;
/*
* We have consecutive bitstrings labels, and
* the more significant label ('head') has
* space.
*/
currbits = curr[1];
if (currbits == 0)
currbits = 256;
currindex = 0;
headbits = head[1];
if (headbits == 0)
headbits = 256;
headindex = headbits;
count = 256 - headbits;
if (count > currbits)
count = currbits;
headrem = headbits % 8;
if (headrem != 0)
headrem = 8 - headrem;
if (headrem != 0) {
if (headrem > count)
headrem = count;
do {
bit = get_bit(&curr[2],
currindex);
set_bit(&head[2], headindex,
bit);
currindex++;
headindex++;
headbits++;
count--;
headrem--;
} while (headrem != 0);
}
tailindex = 0;
tailbits = 0;
while (count > 0) {
bit = get_bit(&curr[2], currindex);
set_bit(tail, tailindex, bit);
currindex++;
tailindex++;
tailbits++;
count--;
}
newbits = 0;
newindex = 0;
if (currindex < currbits) {
while (currindex < currbits) {
bit = get_bit(&curr[2],
currindex);
set_bit(&curr[2], newindex,
bit);
currindex++;
newindex++;
newbits++;
}
INSIST(newbits < 256);
curr[1] = newbits;
count = newbits / 8;
newrem = newbits % 8;
/* Zero remaining pad bits, if any. */
if (newrem != 0) {
count++;
newrem = 8 - newrem;
while (newrem > 0) {
set_bit(&curr[2],
newindex,
0);
newrem--;
newindex++;
}
}
curr += count + 2;
} else {
/* We got rid of curr. */
name->labels--;
}
/* copy head, then tail, then rest to curr. */
count = headbits + tailbits;
INSIST(count <= 256);
curr[0] = DNS_LABELTYPE_BITSTRING;
if (count == 256)
curr[1] = 0;
else
curr[1] = count;
curr += 2;
head += 2;
count = headbits / 8;
if (headbits % 8 != 0)
count++;
while (count > 0) {
*curr++ = *head++;
count--;
}
count = tailbits / 8;
if (tailbits % 8 != 0)
count++;
last = tail;
while (count > 0) {
*curr++ = *last++;
count--;
}
last = name->ndata + name->length;
while (head != last)
*curr++ = *head++;
name->length = (curr - name->ndata);
/*
* The offsets table may now be invalid.
*/
set_offsets(name, offsets, NULL);
goto again;
}
}
n--;
}
}
isc_result_t
dns_name_fromwire(dns_name_t *name, isc_buffer_t *source,
dns_decompress_t *dctx, isc_boolean_t downcase,
isc_buffer_t *target)
{
unsigned char *cdata, *ndata;
unsigned int cused, hops, nrem, nused, labels, n;
unsigned int current, new_current, biggest_pointer;
isc_boolean_t saw_bitstring, done;
fw_state state = fw_start;
unsigned int c;
unsigned char *offsets;
dns_offsets_t odata;
/*
* Copy the possibly-compressed name at source into target,
* decompressing it.
*/
REQUIRE(VALID_NAME(name));
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;
hops = 0;
saw_bitstring = ISC_FALSE;
done = ISC_FALSE;
ndata = (unsigned char *)target->base + target->used;
nrem = target->length - target->used;
if (nrem > 255)
nrem = 255;
nused = 0;
cdata = (unsigned char *)source->base + source->current;
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 (hops == 0)
cused++;
switch (state) {
case fw_start:
if (c < 64) {
labels++;
if (nrem < c + 1)
return (ISC_R_NOSPACE);
nrem -= c + 1;
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;
n = 1;
state = fw_newcurrent;
} else if (c == DNS_LABELTYPE_BITSTRING) {
labels++;
if (nrem == 0)
return (ISC_R_NOSPACE);
nrem--;
nused++;
*ndata++ = c;
saw_bitstring = ISC_TRUE;
state = fw_bitstring;
} else if (c == DNS_LABELTYPE_GLOBALCOMP16) {
/*
* 16-bit pointer.
*/
if ((dctx->allowed & DNS_COMPRESS_GLOBAL16) ==
0)
return (DNS_R_DISALLOWED);
new_current = 0;
n = 2;
state = fw_newcurrent;
} else
return (DNS_R_BADLABELTYPE);
break;
case fw_ordinary:
if (downcase)
c = maptolower[c];
/* FALLTHROUGH */
case fw_copy:
*ndata++ = c;
n--;
if (n == 0)
state = fw_start;
break;
case fw_bitstring:
if (c == 0)
n = 256 / 8;
else
n = c / 8;
if ((c % 8) != 0)
n++;
if (nrem < n + 1)
return (ISC_R_NOSPACE);
nrem -= n + 1;
nused += n + 1;
*ndata++ = c;
state = fw_copy;
break;
case fw_newcurrent:
new_current *= 256;
new_current += c;
n--;
if (n != 0)
break;
if (new_current >= biggest_pointer)
return (DNS_R_BADPOINTER);
biggest_pointer = new_current;
current = new_current;
cdata = (unsigned char *)source->base +
current;
hops++;
if (hops > DNS_POINTER_MAXHOPS)
return (DNS_R_TOOMANYHOPS);
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;
/*
* We should build the offsets table directly.
*/
if (name->offsets != NULL || saw_bitstring)
set_offsets(name, offsets, NULL);
if (saw_bitstring)
compact(name, offsets);
isc_buffer_forward(source, cused);
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_towire(dns_name_t *name, dns_compress_t *cctx, isc_buffer_t *target) {
unsigned int methods;
isc_uint16_t offset;
dns_name_t gp, gs;
isc_boolean_t gf;
isc_uint16_t go;
unsigned char gb[257];
isc_buffer_t gws;
dns_offsets_t po, so, 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);
/*
* If 'name' doesn't have an offsets table, make a clone which
* has one.
*/
if (name->offsets == NULL) {
dns_name_init(&clname, clo);
dns_name_clone(name, &clname);
name = &clname;
}
dns_name_init(&gp, po);
dns_name_init(&gs, so);
isc_buffer_init(&gws, gb, sizeof (gb));
offset = target->used; /*XXX*/
methods = dns_compress_getmethods(cctx);
if ((methods & DNS_COMPRESS_GLOBAL) != 0)
gf = dns_compress_findglobal(cctx, name, &gp, &gs, &go, &gws);
else
gf = ISC_FALSE;
/*
* Will the compression pointer reduce the message size?
*/
if (gf && (gp.length + ((go < 16384) ? 2 : 3)) >= name->length)
gf = ISC_FALSE;
if (gf) {
if (target->length - target->used < gp.length)
return (ISC_R_NOSPACE);
(void)memcpy((unsigned char *)target->base + target->used,
gp.ndata, (size_t)gp.length);
isc_buffer_add(target, gp.length);
if (go < 16384) {
go |= 0xc000;
if (target->length - target->used < 2)
return (ISC_R_NOSPACE);
isc_buffer_putuint16(target, go);
} else {
if (target->length - target->used < 3)
return (ISC_R_NOSPACE);
*((unsigned char*)target->base + target->used) =
DNS_LABELTYPE_GLOBALCOMP16;
isc_buffer_add(target, 1);
isc_buffer_putuint16(target, go);
}
if (gp.length != 0)
dns_compress_add(cctx, &gp, &gs, offset);
} else {
if (target->length - target->used < name->length)
return (ISC_R_NOSPACE);
(void)memcpy((unsigned char *)target->base + target->used,
name->ndata, (size_t)name->length);
isc_buffer_add(target, name->length);
dns_compress_add(cctx, name, NULL, 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, offset;
isc_boolean_t copy_prefix = ISC_TRUE;
isc_boolean_t copy_suffix = ISC_TRUE;
isc_boolean_t saw_bitstring = ISC_FALSE;
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));
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 && name->buffer != NULL) {
target = name->buffer;
isc_buffer_clear(name->buffer);
}
REQUIRE(BINDABLE(name));
/*
* IMPORTANT NOTE
*
* If the most-signficant label in prefix is a bitstring,
* and the least-signficant label in suffix is a bitstring,
* it's possible that compaction could convert them into
* one label. If this happens, then the final size will
* be three bytes less than nrem.
*
* We do not check for this special case, and handling it is
* a little messy; we can't just concatenate and compact,
* because we may only have 255 bytes but might need 258 bytes
* temporarily. There are ways to do this with only 255 bytes,
* which will be implemented later.
*
* For now, we simply reject these few cases as being too
* long.
*/
/*
* Set up.
*/
nrem = target->length - target->used;
ndata = (unsigned char *)target->base + target->used;
if (nrem > 255)
nrem = 255;
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 > nrem) {
MAKE_EMPTY(name);
return (ISC_R_NOSPACE);
}
if (copy_suffix) {
if ((suffix->attributes & DNS_NAMEATTR_ABSOLUTE) != 0)
absolute = ISC_TRUE;
if (copy_prefix &&
suffix->ndata[0] == DNS_LABELTYPE_BITSTRING) {
/*
* We only need to call compact() if both the
* least-significant label of the suffix and the
* most-significant label of the prefix are both
* bitstrings.
*
* A further possible optimization, which we don't do,
* is to not compact() if the suffix bitstring is
* full. It will usually not be full, so I don't
* think this is worth it.
*/
if (prefix->offsets != NULL) {
offset = prefix->offsets[prefix->labels - 1];
if (prefix->ndata[offset] ==
DNS_LABELTYPE_BITSTRING)
saw_bitstring = ISC_TRUE;
} else {
/*
* We don't have an offsets table for prefix,
* and rather than spend the effort to make it
* we'll just compact(), which doesn't cost
* more than computing the offsets table if
* there is no bitstring in prefix.
*/
saw_bitstring = ISC_TRUE;
}
}
if (suffix == name && suffix->buffer == target)
memmove(ndata + prefix_length, suffix->ndata,
suffix->length);
else
memcpy(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))
memcpy(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 || saw_bitstring)) {
INIT_OFFSETS(name, offsets, odata);
set_offsets(name, offsets, NULL);
if (saw_bitstring)
compact(name, offsets);
}
isc_buffer_add(target, name->length);
return (ISC_R_SUCCESS);
}
isc_result_t
dns_name_split(dns_name_t *name,
unsigned int suffixlabels, unsigned int nbits,
dns_name_t *prefix, dns_name_t *suffix)
{
dns_offsets_t name_odata, split_odata;
unsigned char *offsets, *splitoffsets;
isc_result_t result = ISC_R_SUCCESS;
unsigned int splitlabel, bitbytes, mod, len;
unsigned char *p, *src, *dst;
REQUIRE(VALID_NAME(name));
REQUIRE((nbits == 0 &&
suffixlabels > 0 && suffixlabels < name->labels) ||
(nbits != 0 &&
suffixlabels <= name->labels));
REQUIRE(prefix != NULL || suffix != NULL);
REQUIRE(prefix == NULL ||
(VALID_NAME(prefix) &&
prefix->buffer != NULL &&
BINDABLE(prefix)));
REQUIRE(suffix == NULL ||
(VALID_NAME(suffix) &&
suffix->buffer != NULL &&
BINDABLE(suffix)));
/*
* When splitting bitstring labels, if prefix and suffix have the same
* buffer, suffix will overwrite the ndata of prefix, corrupting it.
* If prefix has the ndata of name, then it modifies the bitstring
* label and suffix doesn't have the original available. This latter
* problem could be worked around if it is ever deemed desirable.
*/
REQUIRE(nbits == 0 || prefix == NULL || suffix == NULL ||
(prefix->buffer->base != suffix->buffer->base &&
prefix->buffer->base != name->ndata));
SETUP_OFFSETS(name, offsets, name_odata);
splitlabel = name->labels - suffixlabels;
p = &name->ndata[offsets[splitlabel] + 1];
/*
* When a bit count is specified, ensure that the label is a bitstring
* label and it has more bits than the requested slice.
*/
REQUIRE(nbits == 0 ||
(*(p - 1) == DNS_LABELTYPE_BITSTRING && nbits < 256 &&
(*p == 0 || *p > nbits)));
mod = nbits % 8;
if (prefix != NULL) {
if (nbits > 0) {
isc_buffer_clear(prefix->buffer);
/*
* '2' is for the DNS_LABELTYPE_BITSTRING id
* plus the existing number of bits byte.
*/
len = offsets[splitlabel] + 2;
src = name->ndata;
dst = prefix->buffer->base;
if (src != dst) {
/*
* If these are overlapping names ...
* wow. How bizarre could that be?
*/
INSIST(! (src <= dst && src + len > dst) ||
(dst <= src && dst + len > src));
memcpy(dst, src, len);
p = dst + len - 1;
}
/*
* Set the new bit count.
*/
if (*p == 0)
*p = 256 - nbits;
else
*p = *p - nbits;
/*
* Really one less than the bytes for the bits.
*/
bitbytes = (*p - 1) / 8 + 1;
prefix->length = len + bitbytes;
if (prefix->length > prefix->buffer->length ) {
dns_name_invalidate(prefix);
return(ISC_R_NOSPACE);
}
/*
* All of the bits now need to be shifted to the left
* to fill in the space taken by the removed bits.
* This is wonderfully easy when the number of removed
* bits is an integral multiple of 8, but of course
* life isn't always that easy.
*/
src += len + nbits / 8;
dst = p + 1;
len = bitbytes;
if (mod == 0) {
if ((void *)(name->ndata) ==
prefix->buffer->base &&
len > (unsigned int)(src - dst))
memmove(dst, src, len);
else
memcpy(dst, src, len);
} else {
while (len--) {
*dst = *src++ << mod;
/*
* The 0xff subexpression guards
* against arithmetic sign extension
* by the right shift.
*/
if (len > 0)
*dst++ |=
(*src >> (8 - mod)) &
~(0xFF << mod);
}
/*
* Et voila, the very last byte has
* automatically already had its padding
* fixed by the left shift.
*/
}
prefix->buffer->used = prefix->length;
prefix->ndata = prefix->buffer->base;
/*
* Yes, = is meant here, not ==. The intent is
* to have it set only when INSISTs are turned on,
* to doublecheck the result of set_offsets.
*/
INSIST(len = prefix->length);
INIT_OFFSETS(prefix, splitoffsets, split_odata);
set_offsets(prefix, splitoffsets, prefix);
INSIST(prefix->labels == splitlabel + 1 &&
prefix->length == len);
} else
dns_name_getlabelsequence(name, 0, splitlabel,
prefix);
}
if (suffix != NULL && result == ISC_R_SUCCESS) {
if (nbits > 0) {
bitbytes = (nbits - 1) / 8 + 1;
isc_buffer_clear(suffix->buffer);
/*
* The existing bitcount is in src.
* Set len to the number of bytes to be removed,
* and the suffix length to the number of bytes in
* the new name.
*/
src = &name->ndata[offsets[splitlabel] + 1];
len = (*src++ - 1) / 8 - (bitbytes - 1);
suffix->length = name->length -
offsets[splitlabel] - len;
INSIST(suffix->length > 0);
if (suffix->length > suffix->buffer->length) {
dns_name_invalidate(suffix);
return (ISC_R_NOSPACE);
}
/*
* First set up the bitstring label.
*/
dst = suffix->buffer->base;
*dst++ = DNS_LABELTYPE_BITSTRING;
*dst++ = nbits;
if (len > 0) {
/*
* Remember where the next label starts.
*/
p = src + bitbytes + len;
/*
* Some bytes are being removed from the
* middle of the name because of the truncation
* of bits in the bitstring label. Copy
* the bytes (whether full with 8 bits or not)
* that are being kept.
*/
for (len = bitbytes; len > 0; len--)
*dst++ = *src++;
/*
* Now just copy the rest of the labels of
* the name by adjusting src to point to
* the next label.
*
* 2 == label type byte + bitcount byte.
*/
len = suffix->length - bitbytes - 2;
src = p;
} else
len = suffix->length - 2;
/*
* XXX DCL better way to decide memcpy vs memmove?
*/
if (len > 0) {
if ((dst <= src && dst + len > src) ||
(src <= dst && src + len > dst))
memmove(dst, src, len);
else
memcpy(dst, src, len);
}
suffix->buffer->used = suffix->length;
suffix->ndata = suffix->buffer->base;
/*
* The byte that contains the end of the
* bitstring has its pad bytes (if any) masked
* to zero.
*/
if (mod)
suffix->ndata[bitbytes + 1] &=
0xFF << (8 - mod);
/*
* Yes, = is meant here, not ==. The intent is
* to have it set only when INSISTs are turned on,
* to doublecheck the result of set_offsets.
*/
INSIST(len = suffix->length);
INIT_OFFSETS(suffix, splitoffsets, split_odata);
set_offsets(suffix, splitoffsets, suffix);
INSIST(suffix->labels == suffixlabels &&
suffix->length == len);
} else
dns_name_getlabelsequence(name, splitlabel,
suffixlabels, suffix);
}
return (result);
}
isc_result_t
dns_name_splitatdepth(dns_name_t *name, unsigned int depth,
dns_name_t *prefix, dns_name_t *suffix)
{
unsigned int suffixlabels, nbits, label, count, n;
unsigned char *offsets, *ndata;
dns_offsets_t odata;
/*
* Split 'name' into two pieces at a certain depth.
*/
REQUIRE(VALID_NAME(name));
REQUIRE(name->labels > 0);
REQUIRE(depth > 0);
SETUP_OFFSETS(name, offsets, odata);
suffixlabels = 0;
nbits = 0;
label = name->labels;
do {
label--;
ndata = &name->ndata[offsets[label]];
count = *ndata++;
if (count > 63) {
INSIST(count == DNS_LABELTYPE_BITSTRING);
/*
* Get the number of bits in the bitstring label.
*/
n = *ndata++;
if (n == 0)
n = 256;
suffixlabels++;
if (n <= depth) {
/*
* This entire bitstring is in the suffix.
*/
depth -= n;
} else {
/*
* Only the first 'depth' bits of this
* bitstring are in the suffix.
*/
nbits = depth;
depth = 0;
}
} else {
suffixlabels++;
depth--;
}
} while (depth != 0 && label != 0);
/*
* If depth is not zero, then the caller violated the requirement
* that depth <= dns_name_depth(name).
*/
if (depth != 0) {
REQUIRE(depth <= dns_name_depth(name));
/*
* We should never get here!
*/
INSIST(0);
}
return (dns_name_split(name, suffixlabels, nbits, prefix, suffix));
}
isc_result_t
dns_name_dup(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);
memcpy(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)
memcpy(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);
memcpy(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)
memcpy(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);
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);
}
void
dns_name_format(dns_name_t *name, char *cp, unsigned int size) {
isc_result_t result;
isc_buffer_t buf;
isc_boolean_t omit_final_dot = ISC_TRUE;
REQUIRE(size > 0);
if (dns_name_equal(name, dns_rootname))
omit_final_dot = ISC_FALSE;
/*
* Leave room for null termination after buffer.
*/
isc_buffer_init(&buf, cp, size - 1);
result = dns_name_totext(name, omit_final_dot, &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>");
}
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