/*
+ * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996,1999 by 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.
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+ * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
-#ifndef lint
-static const char rcsid[] = "$Id$";
+#if !defined(_LIBC) && !defined(lint)
+static const char rcsid[] = "$BINDId: ns_name.c,v 8.15 2000/03/30 22:53:46 vixie Exp $";
#endif
#include <sys/types.h>
#include <resolv.h>
#include <string.h>
#include <ctype.h>
+#include <stdlib.h>
+#include <limits.h>
+
+# define SPRINTF(x) ((size_t)sprintf x)
+
+#define NS_TYPE_ELT 0x40 /*%< EDNS0 extended label type */
+#define DNS_LABELTYPE_BITSTRING 0x41
/* Data. */
static const char digits[] = "0123456789";
+static const 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*/
+};
+
/* Forward. */
static int special(int);
static int dn_find(const u_char *, const u_char *,
const u_char * const *,
const u_char * const *);
+static int encode_bitstring(const char **, const char *,
+ unsigned char **, unsigned char **,
+ unsigned const char *);
+static int labellen(const u_char *);
+static int decode_bitstring(const unsigned char **,
+ char *, const char *);
/* Public. */
-/*
- * ns_name_ntop(src, dst, dstsiz)
+/*%
* Convert an encoded domain name to printable ascii as per RFC1035.
+
* return:
- * Number of bytes written to buffer, or -1 (with errno set)
+ *\li Number of bytes written to buffer, or -1 (with errno set)
+ *
* notes:
- * The root is returned as "."
- * All other domains are returned in non absolute form
+ *\li The root is returned as "."
+ *\li All other domains are returned in non absolute form
*/
int
-ns_name_ntop(const u_char *src, char *dst, size_t dstsiz) {
+ns_name_ntop(const u_char *src, char *dst, size_t dstsiz)
+{
const u_char *cp;
char *dn, *eom;
u_char c;
u_int n;
+ int l;
cp = src;
dn = dst;
eom = dst + dstsiz;
while ((n = *cp++) != 0) {
- if ((n & NS_CMPRSFLGS) != 0) {
+ if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
/* Some kind of compression pointer. */
__set_errno (EMSGSIZE);
return (-1);
}
*dn++ = '.';
}
- if (dn + n >= eom) {
+ if ((l = labellen(cp - 1)) < 0) {
+ __set_errno (EMSGSIZE);
+ return(-1);
+ }
+ if (dn + l >= eom) {
__set_errno (EMSGSIZE);
return (-1);
}
- for ((void)NULL; n > 0; n--) {
+ if ((n & NS_CMPRSFLGS) == NS_TYPE_ELT) {
+ int m;
+
+ if (n != DNS_LABELTYPE_BITSTRING) {
+ /* XXX: labellen should reject this case */
+ __set_errno (EINVAL);
+ return(-1);
+ }
+ if ((m = decode_bitstring(&cp, dn, eom)) < 0)
+ {
+ __set_errno (EMSGSIZE);
+ return(-1);
+ }
+ dn += m;
+ continue;
+ }
+ for ((void)NULL; l > 0; l--) {
c = *cp++;
if (special(c)) {
if (dn + 1 >= eom) {
*dn++ = '\0';
return (dn - dst);
}
+libresolv_hidden_def (ns_name_ntop)
+strong_alias (ns_name_ntop, __ns_name_ntop)
-/*
- * ns_name_pton(src, dst, dstsiz)
- * Convert a ascii string into an encoded domain name as per RFC1035.
+/*%
+ * Convert an ascii string into an encoded domain name as per RFC1035.
+ *
* return:
- * -1 if it fails
- * 1 if string was fully qualified
- * 0 is string was not fully qualified
+ *
+ *\li -1 if it fails
+ *\li 1 if string was fully qualified
+ *\li 0 is string was not fully qualified
+ *
* notes:
- * Enforces label and domain length limits.
+ *\li Enforces label and domain length limits.
*/
int
-ns_name_pton(const char *src, u_char *dst, size_t dstsiz) {
+ns_name_pton(const char *src, u_char *dst, size_t dstsiz)
+{
u_char *label, *bp, *eom;
- int c, n, escaped;
+ int c, n, escaped, e = 0;
char *cp;
escaped = 0;
while ((c = *src++) != 0) {
if (escaped) {
- if ((cp = strchr(digits, c)) != NULL) {
+ if (c == '[') { /*%< start a bit string label */
+ if ((cp = strchr(src, ']')) == NULL) {
+ __set_errno (EINVAL);
+ return(-1);
+ }
+ if ((e = encode_bitstring(&src, cp + 2,
+ &label, &bp, eom))
+ != 0) {
+ __set_errno (e);
+ return(-1);
+ }
+ escaped = 0;
+ label = bp++;
+ if ((c = *src++) == 0)
+ goto done;
+ else if (c != '.') {
+ __set_errno (EINVAL);
+ return(-1);
+ }
+ continue;
+ }
+ else if ((cp = strchr(digits, c)) != NULL) {
n = (cp - digits) * 100;
if ((c = *src++) == 0 ||
(cp = strchr(digits, c)) == NULL) {
continue;
} else if (c == '.') {
c = (bp - label - 1);
- if ((c & NS_CMPRSFLGS) != 0) { /* Label too big. */
+ if ((c & NS_CMPRSFLGS) != 0) { /*%< Label too big. */
__set_errno (EMSGSIZE);
return (-1);
}
*bp++ = (u_char)c;
}
c = (bp - label - 1);
- if ((c & NS_CMPRSFLGS) != 0) { /* Label too big. */
+ if ((c & NS_CMPRSFLGS) != 0) { /*%< Label too big. */
__set_errno (EMSGSIZE);
return (-1);
}
+ done:
if (label >= eom) {
__set_errno (EMSGSIZE);
return (-1);
}
*bp++ = 0;
}
- if ((bp - dst) > MAXCDNAME) { /* src too big */
+ if ((bp - dst) > MAXCDNAME) { /*%< src too big */
__set_errno (EMSGSIZE);
return (-1);
}
return (0);
}
+libresolv_hidden_def (ns_name_pton)
-/*
- * ns_name_ntol(src, dst, dstsiz)
+/*%
* Convert a network strings labels into all lowercase.
+ *
* return:
- * Number of bytes written to buffer, or -1 (with errno set)
+ *\li Number of bytes written to buffer, or -1 (with errno set)
+ *
* notes:
- * Enforces label and domain length limits.
+ *\li Enforces label and domain length limits.
*/
int
-ns_name_ntol(const u_char *src, u_char *dst, size_t dstsiz) {
+ns_name_ntol(const u_char *src, u_char *dst, size_t dstsiz)
+{
const u_char *cp;
u_char *dn, *eom;
u_char c;
u_int n;
+ int l;
cp = src;
dn = dst;
eom = dst + dstsiz;
+ if (dn >= eom) {
+ __set_errno (EMSGSIZE);
+ return (-1);
+ }
while ((n = *cp++) != 0) {
- if ((n & NS_CMPRSFLGS) != 0) {
+ if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
/* Some kind of compression pointer. */
__set_errno (EMSGSIZE);
return (-1);
}
*dn++ = n;
- if (dn + n >= eom) {
+ if ((l = labellen(cp - 1)) < 0) {
__set_errno (EMSGSIZE);
return (-1);
}
- for ((void)NULL; n > 0; n--) {
+ if (dn + l >= eom) {
+ __set_errno (EMSGSIZE);
+ return (-1);
+ }
+ for ((void)NULL; l > 0; l--) {
c = *cp++;
if (isupper(c))
*dn++ = tolower(c);
return (dn - dst);
}
-/*
- * ns_name_unpack(msg, eom, src, dst, dstsiz)
+/*%
* Unpack a domain name from a message, source may be compressed.
+ *
* return:
- * -1 if it fails, or consumed octets if it succeeds.
+ *\li -1 if it fails, or consumed octets if it succeeds.
*/
int
ns_name_unpack(const u_char *msg, const u_char *eom, const u_char *src,
{
const u_char *srcp, *dstlim;
u_char *dstp;
- int n, len, checked;
+ int n, len, checked, l;
len = -1;
checked = 0;
/* Check for indirection. */
switch (n & NS_CMPRSFLGS) {
case 0:
+ case NS_TYPE_ELT:
/* Limit checks. */
- if (dstp + n + 1 >= dstlim || srcp + n >= eom) {
+ if ((l = labellen(srcp - 1)) < 0) {
+ __set_errno (EMSGSIZE);
+ return(-1);
+ }
+ if (dstp + l + 1 >= dstlim || srcp + l >= eom) {
__set_errno (EMSGSIZE);
return (-1);
}
- checked += n + 1;
+ checked += l + 1;
*dstp++ = n;
- memcpy(dstp, srcp, n);
- dstp += n;
- srcp += n;
+ memcpy(dstp, srcp, l);
+ dstp += l;
+ srcp += l;
break;
case NS_CMPRSFLGS:
if (len < 0)
len = srcp - src + 1;
srcp = msg + (((n & 0x3f) << 8) | (*srcp & 0xff));
- if (srcp < msg || srcp >= eom) { /* Out of range. */
+ if (srcp < msg || srcp >= eom) { /*%< Out of range. */
__set_errno (EMSGSIZE);
return (-1);
}
default:
__set_errno (EMSGSIZE);
- return (-1); /* flag error */
+ return (-1); /*%< flag error */
}
}
*dstp = '\0';
len = srcp - src;
return (len);
}
+libresolv_hidden_def (ns_name_unpack)
+strong_alias (ns_name_unpack, __ns_name_unpack)
-/*
- * ns_name_pack(src, dst, dstsiz, dnptrs, lastdnptr)
+/*%
* Pack domain name 'domain' into 'comp_dn'.
+ *
* return:
- * Size of the compressed name, or -1.
+ *\li Size of the compressed name, or -1.
+ *
* notes:
- * 'dnptrs' is an array of pointers to previous compressed names.
- * dnptrs[0] is a pointer to the beginning of the message. The array
+ *\li 'dnptrs' is an array of pointers to previous compressed names.
+ *\li dnptrs[0] is a pointer to the beginning of the message. The array
* ends with NULL.
- * 'lastdnptr' is a pointer to the end of the array pointed to
+ *\li 'lastdnptr' is a pointer to the end of the array pointed to
* by 'dnptrs'.
+ *
* Side effects:
- * The list of pointers in dnptrs is updated for labels inserted into
+ *\li The list of pointers in dnptrs is updated for labels inserted into
* the message as we compress the name. If 'dnptr' is NULL, we don't
* try to compress names. If 'lastdnptr' is NULL, we don't update the
* list.
u_char *dstp;
const u_char **cpp, **lpp, *eob, *msg;
const u_char *srcp;
- int n, l;
+ int n, l, first = 1;
srcp = src;
dstp = dst;
if ((msg = *dnptrs++) != NULL) {
for (cpp = dnptrs; *cpp != NULL; cpp++)
(void)NULL;
- lpp = cpp; /* end of list to search */
+ lpp = cpp; /*%< end of list to search */
}
} else
msg = NULL;
/* make sure the domain we are about to add is legal */
l = 0;
do {
+ int l0;
+
n = *srcp;
- if ((n & NS_CMPRSFLGS) != 0) {
+ if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
__set_errno (EMSGSIZE);
return (-1);
}
- l += n + 1;
+ if ((l0 = labellen(srcp)) < 0) {
+ __set_errno (EINVAL);
+ return(-1);
+ }
+ l += l0 + 1;
if (l > MAXCDNAME) {
__set_errno (EMSGSIZE);
return (-1);
}
- srcp += n + 1;
+ srcp += l0 + 1;
} while (n != 0);
/* from here on we need to reset compression pointer array on error */
}
/* Not found, save it. */
if (lastdnptr != NULL && cpp < lastdnptr - 1 &&
- (dstp - msg) < 0x4000) {
+ (dstp - msg) < 0x4000 && first) {
*cpp++ = dstp;
*cpp = NULL;
+ first = 0;
}
}
/* copy label to buffer */
- if (n & NS_CMPRSFLGS) { /* Should not happen. */
+ if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
+ /* Should not happen. */
goto cleanup;
}
+ n = labellen(srcp);
if (dstp + 1 + n >= eob) {
goto cleanup;
}
*lpp = NULL;
__set_errno (EMSGSIZE);
return (-1);
- }
+ }
return (dstp - dst);
}
+libresolv_hidden_def (ns_name_pack)
-/*
- * ns_name_uncompress(msg, eom, src, dst, dstsiz)
+/*%
* Expand compressed domain name to presentation format.
+ *
* return:
- * Number of bytes read out of `src', or -1 (with errno set).
+ *\li Number of bytes read out of `src', or -1 (with errno set).
+ *
* note:
- * Root domain returns as "." not "".
+ *\li Root domain returns as "." not "".
*/
int
ns_name_uncompress(const u_char *msg, const u_char *eom, const u_char *src,
{
u_char tmp[NS_MAXCDNAME];
int n;
-
+
if ((n = ns_name_unpack(msg, eom, src, tmp, sizeof tmp)) == -1)
return (-1);
if (ns_name_ntop(tmp, dst, dstsiz) == -1)
return (-1);
return (n);
}
+libresolv_hidden_def (ns_name_uncompress)
-/*
- * ns_name_compress(src, dst, dstsiz, dnptrs, lastdnptr)
+/*%
* Compress a domain name into wire format, using compression pointers.
+ *
* return:
- * Number of bytes consumed in `dst' or -1 (with errno set).
+ *\li Number of bytes consumed in `dst' or -1 (with errno set).
+ *
* notes:
- * 'dnptrs' is an array of pointers to previous compressed names.
- * dnptrs[0] is a pointer to the beginning of the message.
- * The list ends with NULL. 'lastdnptr' is a pointer to the end of the
+ *\li 'dnptrs' is an array of pointers to previous compressed names.
+ *\li dnptrs[0] is a pointer to the beginning of the message.
+ *\li The list ends with NULL. 'lastdnptr' is a pointer to the end of the
* array pointed to by 'dnptrs'. Side effect is to update the list of
* pointers for labels inserted into the message as we compress the name.
- * If 'dnptr' is NULL, we don't try to compress names. If 'lastdnptr'
+ *\li If 'dnptr' is NULL, we don't try to compress names. If 'lastdnptr'
* is NULL, we don't update the list.
*/
int
return (-1);
return (ns_name_pack(tmp, dst, dstsiz, dnptrs, lastdnptr));
}
+libresolv_hidden_def (ns_name_compress)
-/*
- * ns_name_skip(ptrptr, eom)
+/*%
+ * Reset dnptrs so that there are no active references to pointers at or
+ * after src.
+ */
+void
+ns_name_rollback(const u_char *src, const u_char **dnptrs,
+ const u_char **lastdnptr)
+{
+ while (dnptrs < lastdnptr && *dnptrs != NULL) {
+ if (*dnptrs >= src) {
+ *dnptrs = NULL;
+ break;
+ }
+ dnptrs++;
+ }
+}
+
+/*%
* Advance *ptrptr to skip over the compressed name it points at.
+ *
* return:
- * 0 on success, -1 (with errno set) on failure.
+ *\li 0 on success, -1 (with errno set) on failure.
*/
int
-ns_name_skip(const u_char **ptrptr, const u_char *eom) {
+ns_name_skip(const u_char **ptrptr, const u_char *eom)
+{
const u_char *cp;
u_int n;
+ int l;
cp = *ptrptr;
while (cp < eom && (n = *cp++) != 0) {
/* Check for indirection. */
switch (n & NS_CMPRSFLGS) {
- case 0: /* normal case, n == len */
+ case 0: /*%< normal case, n == len */
cp += n;
continue;
- case NS_CMPRSFLGS: /* indirection */
+ case NS_TYPE_ELT: /*%< EDNS0 extended label */
+ if ((l = labellen(cp - 1)) < 0) {
+ __set_errno (EMSGSIZE);
+ return(-1);
+ }
+ cp += l;
+ continue;
+ case NS_CMPRSFLGS: /*%< indirection */
cp++;
break;
- default: /* illegal type */
+ default: /*%< illegal type */
__set_errno (EMSGSIZE);
return (-1);
}
*ptrptr = cp;
return (0);
}
+libresolv_hidden_def (ns_name_skip)
/* Private. */
-/*
- * special(ch)
+/*%
* Thinking in noninternationalized USASCII (per the DNS spec),
- * is this characted special ("in need of quoting") ?
+ * is this character special ("in need of quoting") ?
+ *
* return:
- * boolean.
+ *\li boolean.
*/
static int
special(int ch) {
switch (ch) {
- case 0x22: /* '"' */
- case 0x2E: /* '.' */
- case 0x3B: /* ';' */
- case 0x5C: /* '\\' */
+ case 0x22: /*%< '"' */
+ case 0x2E: /*%< '.' */
+ case 0x3B: /*%< ';' */
+ case 0x5C: /*%< '\\' */
+ case 0x28: /*%< '(' */
+ case 0x29: /*%< ')' */
/* Special modifiers in zone files. */
- case 0x40: /* '@' */
- case 0x24: /* '$' */
+ case 0x40: /*%< '@' */
+ case 0x24: /*%< '$' */
return (1);
default:
return (0);
}
}
-/*
- * printable(ch)
+/*%
* Thinking in noninternationalized USASCII (per the DNS spec),
* is this character visible and not a space when printed ?
+ *
* return:
- * boolean.
+ *\li boolean.
*/
static int
printable(int ch) {
return (ch > 0x20 && ch < 0x7f);
}
-/*
+/*%
* Thinking in noninternationalized USASCII (per the DNS spec),
* convert this character to lower case if it's upper case.
*/
return (ch);
}
-/*
- * dn_find(domain, msg, dnptrs, lastdnptr)
+/*%
* Search for the counted-label name in an array of compressed names.
+ *
* return:
- * offset from msg if found, or -1.
+ *\li offset from msg if found, or -1.
+ *
* notes:
- * dnptrs is the pointer to the first name on the list,
- * not the pointer to the start of the message.
+ *\li dnptrs is the pointer to the first name on the list,
+ *\li not the pointer to the start of the message.
*/
static int
dn_find(const u_char *domain, const u_char *msg,
u_int n;
for (cpp = dnptrs; cpp < lastdnptr; cpp++) {
- dn = domain;
- sp = cp = *cpp;
- while ((n = *cp++) != 0) {
- /*
- * check for indirection
- */
- switch (n & NS_CMPRSFLGS) {
- case 0: /* normal case, n == len */
- if (n != *dn++)
- goto next;
- for ((void)NULL; n > 0; n--)
- if (mklower(*dn++) != mklower(*cp++))
+ sp = *cpp;
+ /*
+ * terminate search on:
+ * root label
+ * compression pointer
+ * unusable offset
+ */
+ while (*sp != 0 && (*sp & NS_CMPRSFLGS) == 0 &&
+ (sp - msg) < 0x4000) {
+ dn = domain;
+ cp = sp;
+ while ((n = *cp++) != 0) {
+ /*
+ * check for indirection
+ */
+ switch (n & NS_CMPRSFLGS) {
+ case 0: /*%< normal case, n == len */
+ n = labellen(cp - 1); /*%< XXX */
+ if (n != *dn++)
goto next;
- /* Is next root for both ? */
- if (*dn == '\0' && *cp == '\0')
- return (sp - msg);
- if (*dn)
- continue;
- goto next;
-
- case NS_CMPRSFLGS: /* indirection */
- cp = msg + (((n & 0x3f) << 8) | *cp);
- break;
-
- default: /* illegal type */
- __set_errno (EMSGSIZE);
- return (-1);
+
+ for ((void)NULL; n > 0; n--)
+ if (mklower(*dn++) !=
+ mklower(*cp++))
+ goto next;
+ /* Is next root for both ? */
+ if (*dn == '\0' && *cp == '\0')
+ return (sp - msg);
+ if (*dn)
+ continue;
+ goto next;
+ case NS_CMPRSFLGS: /*%< indirection */
+ cp = msg + (((n & 0x3f) << 8) | *cp);
+ break;
+
+ default: /*%< illegal type */
+ __set_errno (EMSGSIZE);
+ return (-1);
+ }
}
+ next: ;
+ sp += *sp + 1;
}
- next: ;
}
__set_errno (ENOENT);
return (-1);
}
+
+static int
+decode_bitstring(const unsigned char **cpp, char *dn, const char *eom)
+{
+ const unsigned char *cp = *cpp;
+ char *beg = dn, tc;
+ int b, blen, plen, i;
+
+ if ((blen = (*cp & 0xff)) == 0)
+ blen = 256;
+ plen = (blen + 3) / 4;
+ plen += sizeof("\\[x/]") + (blen > 99 ? 3 : (blen > 9) ? 2 : 1);
+ if (dn + plen >= eom)
+ return(-1);
+
+ cp++;
+ i = SPRINTF((dn, "\\[x"));
+ if (i < 0)
+ return (-1);
+ dn += i;
+ for (b = blen; b > 7; b -= 8, cp++) {
+ i = SPRINTF((dn, "%02x", *cp & 0xff));
+ if (i < 0)
+ return (-1);
+ dn += i;
+ }
+ if (b > 4) {
+ tc = *cp++;
+ i = SPRINTF((dn, "%02x", tc & (0xff << (8 - b))));
+ if (i < 0)
+ return (-1);
+ dn += i;
+ } else if (b > 0) {
+ tc = *cp++;
+ i = SPRINTF((dn, "%1x",
+ ((tc >> 4) & 0x0f) & (0x0f << (4 - b))));
+ if (i < 0)
+ return (-1);
+ dn += i;
+ }
+ i = SPRINTF((dn, "/%d]", blen));
+ if (i < 0)
+ return (-1);
+ dn += i;
+
+ *cpp = cp;
+ return(dn - beg);
+}
+
+static int
+encode_bitstring(const char **bp, const char *end, unsigned char **labelp,
+ unsigned char ** dst, unsigned const char *eom)
+{
+ int afterslash = 0;
+ const char *cp = *bp;
+ unsigned char *tp;
+ char c;
+ const char *beg_blen;
+ char *end_blen = NULL;
+ int value = 0, count = 0, tbcount = 0, blen = 0;
+
+ beg_blen = end_blen = NULL;
+
+ /* a bitstring must contain at least 2 characters */
+ if (end - cp < 2)
+ return(EINVAL);
+
+ /* XXX: currently, only hex strings are supported */
+ if (*cp++ != 'x')
+ return(EINVAL);
+ if (!isxdigit((*cp) & 0xff)) /*%< reject '\[x/BLEN]' */
+ return(EINVAL);
+
+ for (tp = *dst + 1; cp < end && tp < eom; cp++) {
+ switch((c = *cp)) {
+ case ']': /*%< end of the bitstring */
+ if (afterslash) {
+ if (beg_blen == NULL)
+ return(EINVAL);
+ blen = (int)strtol(beg_blen, &end_blen, 10);
+ if (*end_blen != ']')
+ return(EINVAL);
+ }
+ if (count)
+ *tp++ = ((value << 4) & 0xff);
+ cp++; /*%< skip ']' */
+ goto done;
+ case '/':
+ afterslash = 1;
+ break;
+ default:
+ if (afterslash) {
+ if (!isdigit(c&0xff))
+ return(EINVAL);
+ if (beg_blen == NULL) {
+
+ if (c == '0') {
+ /* blen never begings with 0 */
+ return(EINVAL);
+ }
+ beg_blen = cp;
+ }
+ } else {
+ if (!isxdigit(c&0xff))
+ return(EINVAL);
+ value <<= 4;
+ value += digitvalue[(int)c];
+ count += 4;
+ tbcount += 4;
+ if (tbcount > 256)
+ return(EINVAL);
+ if (count == 8) {
+ *tp++ = value;
+ count = 0;
+ }
+ }
+ break;
+ }
+ }
+ done:
+ if (cp >= end || tp >= eom)
+ return(EMSGSIZE);
+
+ /*
+ * bit length validation:
+ * If a <length> is present, the number of digits in the <bit-data>
+ * MUST be just sufficient to contain the number of bits specified
+ * by the <length>. If there are insignificant bits in a final
+ * hexadecimal or octal digit, they MUST be zero.
+ * RFC2673, Section 3.2.
+ */
+ if (blen > 0) {
+ int traillen;
+
+ if (((blen + 3) & ~3) != tbcount)
+ return(EINVAL);
+ traillen = tbcount - blen; /*%< between 0 and 3 */
+ if (((value << (8 - traillen)) & 0xff) != 0)
+ return(EINVAL);
+ }
+ else
+ blen = tbcount;
+ if (blen == 256)
+ blen = 0;
+
+ /* encode the type and the significant bit fields */
+ **labelp = DNS_LABELTYPE_BITSTRING;
+ **dst = blen;
+
+ *bp = cp;
+ *dst = tp;
+
+ return(0);
+}
+
+static int
+labellen(const u_char *lp)
+{
+ int bitlen;
+ u_char l = *lp;
+
+ if ((l & NS_CMPRSFLGS) == NS_CMPRSFLGS) {
+ /* should be avoided by the caller */
+ return(-1);
+ }
+
+ if ((l & NS_CMPRSFLGS) == NS_TYPE_ELT) {
+ if (l == DNS_LABELTYPE_BITSTRING) {
+ if ((bitlen = *(lp + 1)) == 0)
+ bitlen = 256;
+ return((bitlen + 7 ) / 8 + 1);
+ }
+ return(-1); /*%< unknwon ELT */
+ }
+ return(l);
+}
+
+/*! \file */
projects / thirdparty / glibc.git / blobdiff