summaryrefslogtreecommitdiff
path: root/usr/src/lib/libresolv/res_comp.c
diff options
context:
space:
mode:
Diffstat (limited to 'usr/src/lib/libresolv/res_comp.c')
-rw-r--r--usr/src/lib/libresolv/res_comp.c350
1 files changed, 350 insertions, 0 deletions
diff --git a/usr/src/lib/libresolv/res_comp.c b/usr/src/lib/libresolv/res_comp.c
new file mode 100644
index 0000000000..9835ead5df
--- /dev/null
+++ b/usr/src/lib/libresolv/res_comp.c
@@ -0,0 +1,350 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License, Version 1.0 only
+ * (the "License"). You may not use this file except in compliance
+ * with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 1996 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
+/* All Rights Reserved */
+
+/*
+ * University Copyright- Copyright (c) 1982, 1986, 1988
+ * The Regents of the University of California
+ * All Rights Reserved
+ *
+ * University Acknowledgment- Portions of this document are derived from
+ * software developed by the University of California, Berkeley, and its
+ * contributors.
+ */
+
+#pragma ident "%Z%%M% %I% %E% SMI"
+
+#include "synonyms.h"
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <arpa/nameser.h>
+
+static dn_find();
+
+
+/*
+ * 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.
+ */
+dn_expand(msg, eomorig, comp_dn, exp_dn, length)
+ u_char *msg, *eomorig, *comp_dn, *exp_dn;
+ int length;
+{
+ register u_char *cp, *dn;
+ register int n, c;
+ u_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';
+ 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.
+ */
+dn_comp(exp_dn, comp_dn, length, dnptrs, lastdnptr)
+ u_char *exp_dn, *comp_dn;
+ int length;
+ u_char **dnptrs, **lastdnptr;
+{
+ register u_char *cp, *dn;
+ register int c, l;
+ u_char **cpp, **lpp, *sp, *eob;
+ u_char *msg;
+
+ dn = exp_dn;
+ cp = comp_dn;
+ eob = cp + length;
+ 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'; /*EMPTY*/) {
+ /* 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.
+ */
+dn_skipname(comp_dn, eom)
+ u_char *comp_dn, *eom;
+{
+ register 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;
+ default: /* illegal type */
+ return (-1);
+ case INDIR_MASK: /* indirection */
+ cp++;
+ }
+ break;
+ }
+ return (cp - comp_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
+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 (*dn++ != *cp++)
+ goto next;
+ }
+ if ((n = *dn++) == '\0' && *cp == '\0')
+ return (sp - msg);
+ if (n == '.')
+ continue;
+ goto next;
+
+ default: /* illegal type */
+ return (-1);
+
+ case INDIR_MASK: /* indirection */
+ cp = msg + (((n & 0x3f) << 8) | *cp);
+ }
+ }
+ if (*dn == '\0')
+ return (sp - msg);
+ next: /*EMPTY*/;
+ }
+ 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_short
+_getshort(msgp)
+ u_char *msgp;
+{
+ register u_char *p = (u_char *) msgp;
+#ifdef vax
+ /*
+ * vax compiler doesn't put shorts in registers
+ */
+ register u_long u;
+#else
+ register u_short u;
+#endif
+
+ u = *p++ << 8;
+ return ((u_short)(u | *p));
+}
+
+u_long
+_getlong(msgp)
+ u_char *msgp;
+{
+ register u_char *p = (u_char *) msgp;
+ register u_long u;
+
+ u = *p++; u <<= 8;
+ u |= *p++; u <<= 8;
+ u |= *p++; u <<= 8;
+ return (u | *p);
+}
+
+
+putshort(s, msgp)
+ register u_short s;
+ register u_char *msgp;
+{
+
+ msgp[1] = s;
+ msgp[0] = s >> 8;
+}
+
+putlong(l, msgp)
+ register u_long l;
+ register u_char *msgp;
+{
+
+ msgp[3] = l;
+ msgp[2] = (l >>= 8);
+ msgp[1] = (l >>= 8);
+ msgp[0] = l >> 8;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-06-26 13:31:14 +0000