2 * ++Copyright++ 1985, 1993
4 * Copyright (c) 1985, 1993
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
37 * Permission to use, copy, modify, and distribute this software for any
38 * purpose with or without fee is hereby granted, provided that the above
39 * copyright notice and this permission notice appear in all copies, and that
40 * the name of Digital Equipment Corporation not be used in advertising or
41 * publicity pertaining to distribution of the document or software without
42 * specific, written prior permission.
44 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
45 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
46 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
47 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
48 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
49 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
50 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
56 #if defined(LIBC_SCCS) && !defined(lint)
57 static char sccsid
[] = "@(#)res_comp.c 8.1 (Berkeley) 6/4/93";
58 static char rcsid
[] = "$Id$";
59 #endif /* LIBC_SCCS and not lint */
61 #include <sys/param.h>
62 #include <netinet/in.h>
63 #include <arpa/nameser.h>
69 #if defined(BSD) && (BSD >= 199103)
73 # include "../conf/portability.h"
76 static int dn_find
__P((u_char
*exp_dn
, u_char
*msg
,
77 u_char
**dnptrs
, u_char
**lastdnptr
));
80 * Expand compressed domain name 'comp_dn' to full domain name.
81 * 'msg' is a pointer to the begining of the message,
82 * 'eomorig' points to the first location after the message,
83 * 'exp_dn' is a pointer to a buffer of size 'length' for the result.
84 * Return size of compressed name or -1 if there was an error.
87 dn_expand(msg
, eomorig
, comp_dn
, exp_dn
, length
)
88 const u_char
*msg
, *eomorig
, *comp_dn
;
92 register const u_char
*cp
;
96 int len
= -1, checked
= 0;
100 eom
= exp_dn
+ length
;
102 * fetch next label in domain name
106 * Check for indirection
108 switch (n
& INDIR_MASK
) {
119 if ((c
= *cp
++) == '.') {
120 if (dn
+ n
+ 2 >= eom
)
125 if (cp
>= eomorig
) /* out of range */
132 len
= cp
- comp_dn
+ 1;
133 cp
= msg
+ (((n
& 0x3f) << 8) | (*cp
& 0xff));
134 if (cp
< msg
|| cp
>= eomorig
) /* out of range */
138 * Check for loops in the compressed name;
139 * if we've looked at the whole message,
140 * there must be a loop.
142 if (checked
>= eomorig
- msg
)
147 return (-1); /* flag error */
151 for (dn
= exp_dn
; (c
= *dn
) != '\0'; dn
++)
152 if (isascii(c
) && isspace(c
))
160 * Compress domain name 'exp_dn' into 'comp_dn'.
161 * Return the size of the compressed name or -1.
162 * 'length' is the size of the array pointed to by 'comp_dn'.
163 * 'dnptrs' is a list of pointers to previous compressed names. dnptrs[0]
164 * is a pointer to the beginning of the message. The list ends with NULL.
165 * 'lastdnptr' is a pointer to the end of the arrary pointed to
166 * by 'dnptrs'. Side effect is to update the list of pointers for
167 * labels inserted into the message as we compress the name.
168 * If 'dnptr' is NULL, we don't try to compress names. If 'lastdnptr'
169 * is NULL, we don't update the list.
172 dn_comp(exp_dn
, comp_dn
, length
, dnptrs
, lastdnptr
)
174 u_char
*comp_dn
, **dnptrs
, **lastdnptr
;
177 register u_char
*cp
, *dn
;
179 u_char
**cpp
, **lpp
, *sp
, *eob
;
182 dn
= (u_char
*)exp_dn
;
186 if (dnptrs
!= NULL
) {
187 if ((msg
= *dnptrs
++) != NULL
) {
188 for (cpp
= dnptrs
; *cpp
!= NULL
; cpp
++)
190 lpp
= cpp
; /* end of list to search */
194 for (c
= *dn
++; c
!= '\0'; ) {
195 /* look to see if we can use pointers */
197 if ((l
= dn_find(dn
-1, msg
, dnptrs
, lpp
)) >= 0) {
200 *cp
++ = (l
>> 8) | INDIR_MASK
;
202 return (cp
- comp_dn
);
204 /* not found, save it */
205 if (lastdnptr
!= NULL
&& cpp
< lastdnptr
-1) {
210 sp
= cp
++; /* save ptr to length byte */
217 if ((c
= *dn
++) == '\0')
226 } while ((c
= *dn
++) != '\0');
227 /* catch trailing '.'s but not '..' */
228 if ((l
= cp
- sp
- 1) == 0 && c
== '\0') {
232 if (l
<= 0 || l
> MAXLABEL
) {
245 return (cp
- comp_dn
);
249 * Skip over a compressed domain name. Return the size or -1.
252 __dn_skipname(comp_dn
, eom
)
253 const u_char
*comp_dn
, *eom
;
255 register const u_char
*cp
;
259 while (cp
< eom
&& (n
= *cp
++)) {
261 * check for indirection
263 switch (n
& INDIR_MASK
) {
264 case 0: /* normal case, n == len */
267 case INDIR_MASK
: /* indirection */
270 default: /* illegal type */
277 return (cp
- comp_dn
);
284 if (isascii(ch
) && isupper(ch
))
285 return (tolower(ch
));
290 * Search for expanded name from a list of previously compressed names.
291 * Return the offset from msg if found or -1.
292 * dnptrs is the pointer to the first name on the list,
293 * not the pointer to the start of the message.
296 dn_find(exp_dn
, msg
, dnptrs
, lastdnptr
)
297 u_char
*exp_dn
, *msg
;
298 u_char
**dnptrs
, **lastdnptr
;
300 register u_char
*dn
, *cp
, **cpp
;
304 for (cpp
= dnptrs
; cpp
< lastdnptr
; cpp
++) {
309 * check for indirection
311 switch (n
& INDIR_MASK
) {
312 case 0: /* normal case, n == len */
318 if (mklower(*dn
++) != mklower(*cp
++))
321 if ((n
= *dn
++) == '\0' && *cp
== '\0')
327 case INDIR_MASK
: /* indirection */
328 cp
= msg
+ (((n
& 0x3f) << 8) | *cp
);
331 default: /* illegal type */
343 * Routines to insert/extract short/long's.
348 register const u_char
*msgp
;
350 register u_int16_t u
;
358 * nExt machines have some funky library conventions, which we must maintain.
362 register const u_char
*msgp
;
364 return (_getshort(msgp
));
370 register const u_char
*msgp
;
372 register u_int32_t u
;
379 #if defined(__STDC__) || defined(__cplusplus)
380 __putshort(register u_int16_t s
, register u_char
*msgp
) /* must match proto */
383 register u_int16_t s
;
384 register u_char
*msgp
;
392 register u_int32_t l
;
393 register u_char
*msgp
;
399 /* ultrix 4.0 had some icky packaging in its libc.a. alias for it here.
400 * there is more gunk of this kind over in res_debug.c.
404 #if defined(__STDC__) || defined(__cplusplus)
405 putshort(register u_short s
, register u_char
*msgp
)
409 register u_char
*msgp
;
417 register u_int32_t l
;
418 register u_char
*msgp
;
424 dn_skipname(comp_dn
, eom
)
425 const u_char
*comp_dn
, *eom
;
427 return (__dn_skipname(comp_dn
, eom
));
429 #endif /* Ultrix 4.0 hackery */