+/* Domain name processing functions.
+ Copyright (C) 1995-2021 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
/*
- * ++Copyright++ 1985, 1993
- * -
* Copyright (c) 1985, 1993
* The Regents of the University of California. All rights reserved.
- *
+ *
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
- *
+ *
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
- * -
+ */
+
+/*
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
- *
+ *
* 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, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
- *
+ *
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* 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.
- * -
- * --Copyright--
*/
-#if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)res_comp.c 8.1 (Berkeley) 6/4/93";
-static char rcsid[] = "$Id$";
-#endif /* LIBC_SCCS and not lint */
+/*
+ * Portions 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.
+ */
+#include <sys/types.h>
#include <sys/param.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
-
-#include <stdio.h>
-#include <resolv.h>
#include <ctype.h>
-
-#if defined(BSD) && (BSD >= 199103)
-# include <unistd.h>
-# include <string.h>
-#else
-# include "../conf/portability.h"
-#endif
-
-static int dn_find __P((u_char *exp_dn, u_char *msg,
- u_char **dnptrs, u_char **lastdnptr));
+#include <resolv.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
/*
* Expand compressed domain name 'comp_dn' to full domain name.
- * 'msg' is a pointer to the begining of the message,
+ * 'msg' is a pointer to the beginning of the message,
* 'eomorig' points to the first location after the message,
* 'exp_dn' is a pointer to a buffer of size 'length' for the result.
* Return size of compressed name or -1 if there was an error.
*/
int
-dn_expand(msg, eomorig, comp_dn, exp_dn, length)
- const u_char *msg, *eomorig, *comp_dn;
- char *exp_dn;
- int length;
+dn_expand(const u_char *msg, const u_char *eom, const u_char *src,
+ char *dst, int dstsiz)
{
- register const u_char *cp;
- register char *dn;
- register int n, c;
- char *eom;
- int len = -1, checked = 0;
+ int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz);
- dn = exp_dn;
- cp = comp_dn;
- eom = exp_dn + length;
- /*
- * fetch next label in domain name
- */
- while (n = *cp++) {
- /*
- * Check for indirection
- */
- switch (n & INDIR_MASK) {
- case 0:
- if (dn != exp_dn) {
- if (dn >= eom)
- return (-1);
- *dn++ = '.';
- }
- if (dn+n >= eom)
- return (-1);
- checked += n + 1;
- while (--n >= 0) {
- if ((c = *cp++) == '.') {
- if (dn + n + 2 >= eom)
- return (-1);
- *dn++ = '\\';
- }
- *dn++ = c;
- if (cp >= eomorig) /* out of range */
- return (-1);
- }
- break;
-
- case INDIR_MASK:
- if (len < 0)
- len = cp - comp_dn + 1;
- cp = msg + (((n & 0x3f) << 8) | (*cp & 0xff));
- if (cp < msg || cp >= eomorig) /* out of range */
- return (-1);
- checked += 2;
- /*
- * Check for loops in the compressed name;
- * if we've looked at the whole message,
- * there must be a loop.
- */
- if (checked >= eomorig - msg)
- return (-1);
- break;
-
- default:
- return (-1); /* flag error */
- }
- }
- *dn = '\0';
- for (dn = exp_dn; (c = *dn) != '\0'; dn++)
- if (isascii(c) && isspace(c))
- return (-1);
- if (len < 0)
- len = cp - comp_dn;
- return (len);
+ if (n > 0 && dst[0] == '.')
+ dst[0] = '\0';
+ return (n);
}
+libresolv_hidden_def (dn_expand)
/*
- * Compress domain name 'exp_dn' into 'comp_dn'.
+ * Pack domain name 'exp_dn' in presentation form into 'comp_dn'.
* Return the size of the compressed name or -1.
* 'length' is the size of the array pointed to by 'comp_dn'.
- * 'dnptrs' is a list 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 arrary 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'
- * is NULL, we don't update the list.
*/
int
-dn_comp(exp_dn, comp_dn, length, dnptrs, lastdnptr)
- const char *exp_dn;
- u_char *comp_dn, **dnptrs, **lastdnptr;
- int length;
+dn_comp(const char *src, u_char *dst, int dstsiz,
+ u_char **dnptrs, u_char **lastdnptr)
{
- register u_char *cp, *dn;
- register int c, l;
- u_char **cpp, **lpp, *sp, *eob;
- u_char *msg;
-
- dn = (u_char *)exp_dn;
- cp = comp_dn;
- eob = cp + length;
- lpp = cpp = NULL;
- if (dnptrs != NULL) {
- if ((msg = *dnptrs++) != NULL) {
- for (cpp = dnptrs; *cpp != NULL; cpp++)
- ;
- lpp = cpp; /* end of list to search */
- }
- } else
- msg = NULL;
- for (c = *dn++; c != '\0'; ) {
- /* look to see if we can use pointers */
- if (msg != NULL) {
- if ((l = dn_find(dn-1, msg, dnptrs, lpp)) >= 0) {
- if (cp+1 >= eob)
- return (-1);
- *cp++ = (l >> 8) | INDIR_MASK;
- *cp++ = l % 256;
- return (cp - comp_dn);
- }
- /* not found, save it */
- if (lastdnptr != NULL && cpp < lastdnptr-1) {
- *cpp++ = cp;
- *cpp = NULL;
- }
- }
- sp = cp++; /* save ptr to length byte */
- do {
- if (c == '.') {
- c = *dn++;
- break;
- }
- if (c == '\\') {
- if ((c = *dn++) == '\0')
- break;
- }
- if (cp >= eob) {
- if (msg != NULL)
- *lpp = NULL;
- return (-1);
- }
- *cp++ = c;
- } while ((c = *dn++) != '\0');
- /* catch trailing '.'s but not '..' */
- if ((l = cp - sp - 1) == 0 && c == '\0') {
- cp--;
- break;
- }
- if (l <= 0 || l > MAXLABEL) {
- if (msg != NULL)
- *lpp = NULL;
- return (-1);
- }
- *sp = l;
- }
- if (cp >= eob) {
- if (msg != NULL)
- *lpp = NULL;
- return (-1);
- }
- *cp++ = '\0';
- return (cp - comp_dn);
+ return (ns_name_compress(src, dst, (size_t)dstsiz,
+ (const u_char **)dnptrs,
+ (const u_char **)lastdnptr));
}
+libresolv_hidden_def (dn_comp)
/*
* Skip over a compressed domain name. Return the size or -1.
*/
int
-__dn_skipname(comp_dn, eom)
- const u_char *comp_dn, *eom;
-{
- register const u_char *cp;
- register int n;
+dn_skipname(const u_char *ptr, const u_char *eom) {
+ const u_char *saveptr = ptr;
- cp = comp_dn;
- while (cp < eom && (n = *cp++)) {
- /*
- * check for indirection
- */
- switch (n & INDIR_MASK) {
- case 0: /* normal case, n == len */
- cp += n;
- continue;
- case INDIR_MASK: /* indirection */
- cp++;
- break;
- default: /* illegal type */
- return (-1);
- }
- break;
- }
- if (cp > eom)
+ if (ns_name_skip(&ptr, eom) == -1)
return (-1);
- return (cp - comp_dn);
+ return (ptr - saveptr);
}
+libresolv_hidden_def (dn_skipname)
-static int
-mklower(ch)
- register int ch;
+/* Return true if the string consists of printable ASCII characters
+ only. */
+static bool
+printable_string (const char *dn)
{
- if (isascii(ch) && isupper(ch))
- return (tolower(ch));
- return (ch);
+ while (true)
+ {
+ char ch = *dn;
+ if (ch == '\0')
+ return true;
+ if (ch <= ' ' || ch > '~')
+ return false;
+ ++dn;
+ }
}
-/*
- * Search for expanded name from a list of previously compressed names.
- * Return the offset from msg if found or -1.
- * dnptrs is the pointer to the first name on the list,
- * not the pointer to the start of the message.
- */
-static int
-dn_find(exp_dn, msg, dnptrs, lastdnptr)
- u_char *exp_dn, *msg;
- u_char **dnptrs, **lastdnptr;
+/* Return true if DN points to a name consisting only of [0-9a-zA-Z_-]
+ characters. DN must be in DNS wire format, without
+ compression. */
+static bool
+binary_hnok (const unsigned char *dn)
{
- register u_char *dn, *cp, **cpp;
- register int n;
- u_char *sp;
-
- for (cpp = dnptrs; cpp < lastdnptr; cpp++) {
- dn = exp_dn;
- sp = cp = *cpp;
- while (n = *cp++) {
- /*
- * check for indirection
- */
- switch (n & INDIR_MASK) {
- case 0: /* normal case, n == len */
- while (--n >= 0) {
- if (*dn == '.')
- goto next;
- if (*dn == '\\')
- dn++;
- if (mklower(*dn++) != mklower(*cp++))
- goto next;
- }
- if ((n = *dn++) == '\0' && *cp == '\0')
- return (sp - msg);
- if (n == '.')
- continue;
- goto next;
-
- case INDIR_MASK: /* indirection */
- cp = msg + (((n & 0x3f) << 8) | *cp);
- break;
-
- default: /* illegal type */
- return (-1);
- }
- }
- if (*dn == '\0')
- return (sp - msg);
- next: ;
+ while (true)
+ {
+ size_t label_length = *dn;
+ if (label_length == 0)
+ break;
+ ++dn;
+ const unsigned char *label_end = dn + label_length;
+ do
+ {
+ unsigned char ch = *dn;
+ if (!(('0' <= ch && ch <= '9')
+ || ('A' <= ch && ch <= 'Z')
+ || ('a' <= ch && ch <= 'z')
+ || ch == '-' || ch == '_'))
+ return false;
+ ++dn;
}
- return (-1);
+ while (dn < label_end);
+ }
+ return true;
}
-/*
- * Routines to insert/extract short/long's.
- */
-
-u_int16_t
-_getshort(msgp)
- register const u_char *msgp;
+/* Return true if the binary domain name has a first labels which
+ starts with '-'. */
+static inline bool
+binary_leading_dash (const unsigned char *dn)
{
- register u_int16_t u;
-
- GETSHORT(u, msgp);
- return (u);
+ return dn[0] > 0 && dn[1] == '-';
}
-#ifdef NeXT
-/*
- * nExt machines have some funky library conventions, which we must maintain.
- */
-u_int16_t
-res_getshort(msgp)
- register const u_char *msgp;
+/* Return 1 if res_hnok is a valid host name. Labels must only
+ contain [0-9a-zA-Z_-] characters, and the name must not start with
+ a '-'. The latter is to avoid confusion with program options. */
+int
+res_hnok (const char *dn)
{
- return (_getshort(msgp));
+ unsigned char buf[NS_MAXCDNAME];
+ if (!printable_string (dn)
+ || ns_name_pton (dn, buf, sizeof (buf)) < 0
+ || binary_leading_dash (buf))
+ return 0;
+ return binary_hnok (buf);
}
-#endif
+libresolv_hidden_def (res_hnok)
-u_int32_t
-_getlong(msgp)
- register const u_char *msgp;
+/* Hostname-like (A, MX, WKS) owners can have "*" as their first label
+ but must otherwise be as a host name. */
+int
+res_ownok (const char *dn)
{
- register u_int32_t u;
-
- GETLONG(u, msgp);
- return (u);
+ unsigned char buf[NS_MAXCDNAME];
+ if (!printable_string (dn)
+ || ns_name_pton (dn, buf, sizeof (buf)) < 0
+ || binary_leading_dash (buf))
+ return 0;
+ if (buf[0] == 1 && buf [1] == '*')
+ /* Skip over the leading "*." part. */
+ return binary_hnok (buf + 2);
+ else
+ return binary_hnok (buf);
}
-void
-#if defined(__STDC__) || defined(__cplusplus)
-__putshort(register u_int16_t s, register u_char *msgp) /* must match proto */
-#else
-__putshort(s, msgp)
- register u_int16_t s;
- register u_char *msgp;
-#endif
+/* SOA RNAMEs and RP RNAMEs can have any byte in their first label,
+ but the rest of the name has to look like a host name. */
+int
+res_mailok (const char *dn)
{
- PUTSHORT(s, msgp);
+ unsigned char buf[NS_MAXCDNAME];
+ if (!printable_string (dn)
+ || ns_name_pton (dn, buf, sizeof (buf)) < 0)
+ return 0;
+ unsigned char label_length = buf[0];
+ /* "." is a valid missing representation */
+ if (label_length == 0)
+ return 1;
+ /* Skip over the first label. */
+ unsigned char *tail = buf + 1 + label_length;
+ if (*tail == 0)
+ /* More than one label is required (except for "."). */
+ return 0;
+ return binary_hnok (tail);
}
-void
-__putlong(l, msgp)
- register u_int32_t l;
- register u_char *msgp;
+/* Return 1 if DN is a syntactically valid domain name. Empty names
+ are accepted. */
+int
+res_dnok (const char *dn)
{
- PUTLONG(l, msgp);
+ unsigned char buf[NS_MAXCDNAME];
+ return printable_string (dn) && ns_name_pton (dn, buf, sizeof (buf)) >= 0;
}
+libresolv_hidden_def (res_dnok)
-#ifdef ultrix
-/* ultrix 4.0 had some icky packaging in its libc.a. alias for it here.
- * there is more gunk of this kind over in res_debug.c.
+/*
+ * This module must export the following externally-visible symbols:
+ * ___putlong
+ * ___putshort
+ * __getlong
+ * __getshort
+ * Note that one _ comes from C and the others come from us.
*/
-#undef putshort
-void
-#if defined(__STDC__) || defined(__cplusplus)
-putshort(register u_short s, register u_char *msgp)
-#else
-putshort(s, msgp)
- register u_short s;
- register u_char *msgp;
+void __putlong(uint32_t src, u_char *dst) { ns_put32(src, dst); }
+libresolv_hidden_def (__putlong)
+void __putshort(uint16_t src, u_char *dst) { ns_put16(src, dst); }
+libresolv_hidden_def (__putshort)
+uint32_t _getlong(const u_char *src) { return (ns_get32(src)); }
+uint16_t _getshort(const u_char *src) { return (ns_get16(src)); }
+\f
+
+#include <shlib-compat.h>
+
+#if SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2)
+# undef dn_expand
+weak_alias (__dn_expand, dn_expand);
#endif
-{
- __putshort(s, msgp);
-}
-#undef putlong
-void
-putlong(l, msgp)
- register u_int32_t l;
- register u_char *msgp;
-{
- __putlong(l, msgp);
-}
-
-#undef dn_skipname
-dn_skipname(comp_dn, eom)
- const u_char *comp_dn, *eom;
-{
- return (__dn_skipname(comp_dn, eom));
-}
-#endif /* Ultrix 4.0 hackery */
projects / thirdparty / glibc.git / blobdiff