aboutsummaryrefslogtreecommitdiff
path: root/resolv/res_comp.c
diff options
context:
space:
mode:
Diffstat (limited to 'resolv/res_comp.c')
-rw-r--r--resolv/res_comp.c433
1 files changed, 433 insertions, 0 deletions
diff --git a/resolv/res_comp.c b/resolv/res_comp.c
new file mode 100644
index 0000000000..ad24a984a1
--- /dev/null
+++ b/resolv/res_comp.c
@@ -0,0 +1,433 @@
+/*
+ * ++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:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 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
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * 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
+ * CORPORATION 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.
+ * -
+ * --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 */
+
+#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));
+
+/*
+ * Expand compressed domain name 'comp_dn' to full domain name.
+ * 'msg' is a pointer to the begining 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;
+{
+ register const u_char *cp;
+ register char *dn;
+ register int n, c;
+ char *eom;
+ int len = -1, checked = 0;
+
+ 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);
+}
+
+/*
+ * Compress domain name 'exp_dn' 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;
+{
+ 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);
+}
+
+/*
+ * 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;
+
+ 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)
+ return (-1);
+ return (cp - comp_dn);
+}
+
+static int
+mklower(ch)
+ register int ch;
+{
+ if (isascii(ch) && isupper(ch))
+ return (tolower(ch));
+ return (ch);
+}
+
+/*
+ * 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;
+{
+ 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: ;
+ }
+ return (-1);
+}
+
+/*
+ * Routines to insert/extract short/long's. Must account for byte
+ * order and non-alignment problems. This code at least has the
+ * advantage of being portable.
+ *
+ * used by sendmail.
+ */
+
+u_int16_t
+_getshort(msgp)
+ register const u_char *msgp;
+{
+ register u_int16_t u;
+
+ GETSHORT(u, msgp);
+ return (u);
+}
+
+#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 (_getshort(msgp));
+}
+#endif
+
+u_int32_t
+_getlong(msgp)
+ register const u_char *msgp;
+{
+ register u_int32_t u;
+
+ GETLONG(u, msgp);
+ return (u);
+}
+
+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
+{
+ PUTSHORT(s, msgp);
+}
+
+void
+__putlong(l, msgp)
+ register u_int32_t l;
+ register u_char *msgp;
+{
+ PUTLONG(l, msgp);
+}
+
+#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.
+ */
+#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;
+#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 */
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 00:20:49 +0000