2 * Copyright (c) 1985, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
33 * Permission to use, copy, modify, and distribute this software for any
34 * purpose with or without fee is hereby granted, provided that the above
35 * copyright notice and this permission notice appear in all copies, and that
36 * the name of Digital Equipment Corporation not be used in advertising or
37 * publicity pertaining to distribution of the document or software without
38 * specific, written prior permission.
40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
53 * Permission to use, copy, modify, and distribute this software for any
54 * purpose with or without fee is hereby granted, provided that the above
55 * copyright notice and this permission notice appear in all copies.
57 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
58 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
59 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
60 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
61 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
62 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
63 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
67 /* Original copyright ISC as above.
68 * Code modified specifically for ircd use from the following orginal files
80 #include "ircd_defs.h"
88 #define NS_TYPE_ELT 0x40 /* EDNS0 extended label type */
89 #define DNS_LABELTYPE_BITSTRING 0x41
90 #define DNS_MAXLINE 128
92 /* $Id: reslib.c 1695 2006-06-27 15:11:23Z jilles $ */
93 /* from Hybrid Id: reslib.c 177 2005-10-22 09:05:05Z michael $ */
95 struct rb_sockaddr_storage irc_nsaddr_list
[IRCD_MAXNS
];
97 char irc_domain
[IRCD_RES_HOSTLEN
+ 1];
99 static const char digitvalue
[256] = {
100 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*16*/
101 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*32*/
102 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*48*/
103 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, /*64*/
104 -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*80*/
105 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*96*/
106 -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*112*/
107 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*128*/
108 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
109 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
110 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
111 -1, -1, -1, -1, -1, -1, -1, -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,
113 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
114 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
115 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*256*/
118 static int parse_resvconf(void);
119 static void add_nameserver(const char *);
121 static const char digits
[] = "0123456789";
122 static int labellen(const unsigned char *lp
);
123 static int special(int ch
);
124 static int printable(int ch
);
125 static int irc_decode_bitstring(const char **cpp
, char *dn
, const char *eom
);
126 static int irc_ns_name_compress(const char *src
, unsigned char *dst
, size_t dstsiz
,
127 const unsigned char **dnptrs
, const unsigned char **lastdnptr
);
128 static int irc_dn_find(const unsigned char *, const unsigned char *, const unsigned char * const *,
129 const unsigned char * const *);
130 static int irc_encode_bitsring(const char **, const char *, unsigned char **, unsigned char **,
132 static int irc_ns_name_uncompress(const unsigned char *, const unsigned char *,
133 const unsigned char *, char *, size_t);
134 static int irc_ns_name_unpack(const unsigned char *, const unsigned char *,
135 const unsigned char *, unsigned char *,
137 static int irc_ns_name_ntop(const char *, char *, size_t);
138 static int irc_ns_name_skip(const unsigned char **, const unsigned char *);
139 static int mklower(int ch
);
146 if (irc_nscount
== 0)
147 add_nameserver("127.0.0.1");
154 * output - -1 if failure 0 if success
155 * side effects - fills in irc_nsaddr_list
163 char input
[DNS_MAXLINE
];
166 /* XXX "/etc/resolv.conf" should be from a define in setup.h perhaps
167 * for cygwin support etc. this hardcodes it to unix for now -db
169 if ((file
= fopen("/etc/resolv.conf", "r")) == NULL
)
172 while (fgets(input
, sizeof(input
), file
) != NULL
)
174 /* blow away any newline */
175 if ((p
= strpbrk(input
, "\r\n")) != NULL
)
179 /* skip until something thats not a space is seen */
182 /* if at this point, have a '\0' then continue */
186 /* Ignore comment lines immediately */
187 if (*p
== '#' || *p
== ';')
190 /* skip until a space is found */
192 while (!isspace(*p
) && *p
!= '\0')
195 continue; /* no arguments?.. ignore this line */
196 /* blow away the space character */
199 /* skip these spaces that are before the argument */
202 /* Now arg should be right where p is pointing */
204 if ((p
= strpbrk(arg
, " \t")) != NULL
)
205 *p
= '\0'; /* take the first word */
207 if (strcasecmp(opt
, "domain") == 0)
208 rb_strlcpy(irc_domain
, arg
, sizeof(irc_domain
));
209 else if (strcasecmp(opt
, "nameserver") == 0)
219 * input - either an IPV4 address in dotted quad
220 * or an IPV6 address in : format
222 * side effects - entry in irc_nsaddr_list is filled in as needed
225 add_nameserver(const char *arg
)
227 struct addrinfo hints
, *res
;
229 /* Done max number of nameservers? */
230 if (irc_nscount
>= IRCD_MAXNS
)
233 memset(&hints
, 0, sizeof(hints
));
234 hints
.ai_family
= PF_UNSPEC
;
235 hints
.ai_socktype
= SOCK_DGRAM
;
236 hints
.ai_flags
= AI_PASSIVE
| AI_NUMERICHOST
;
238 if (getaddrinfo(arg
, "domain", &hints
, &res
))
244 memcpy(&irc_nsaddr_list
[irc_nscount
], res
->ai_addr
, res
->ai_addrlen
);
245 SET_SS_LEN(&irc_nsaddr_list
[irc_nscount
], res
->ai_addrlen
);
251 * Expand compressed domain name 'comp_dn' to full domain name.
252 * 'msg' is a pointer to the begining of the message,
253 * 'eomorig' points to the first location after the message,
254 * 'exp_dn' is a pointer to a buffer of size 'length' for the result.
255 * Return size of compressed name or -1 if there was an error.
258 irc_dn_expand(const unsigned char *msg
, const unsigned char *eom
,
259 const unsigned char *src
, char *dst
, int dstsiz
)
261 int n
= irc_ns_name_uncompress(msg
, eom
, src
, dst
, (size_t)dstsiz
);
263 if (n
> 0 && dst
[0] == '.')
269 * irc_ns_name_uncompress(msg, eom, src, dst, dstsiz)
270 * Expand compressed domain name to presentation format.
272 * Number of bytes read out of `src', or -1 (with errno set).
274 * Root domain returns as "." not "".
277 irc_ns_name_uncompress(const unsigned char *msg
, const unsigned char *eom
,
278 const unsigned char *src
, char *dst
, size_t dstsiz
)
280 unsigned char tmp
[NS_MAXCDNAME
];
283 if ((n
= irc_ns_name_unpack(msg
, eom
, src
, tmp
, sizeof tmp
)) == -1)
285 if (irc_ns_name_ntop((char*)tmp
, dst
, dstsiz
) == -1)
290 * irc_ns_name_unpack(msg, eom, src, dst, dstsiz)
291 * Unpack a domain name from a message, source may be compressed.
293 * -1 if it fails, or consumed octets if it succeeds.
296 irc_ns_name_unpack(const unsigned char *msg
, const unsigned char *eom
,
297 const unsigned char *src
, unsigned char *dst
,
300 const unsigned char *srcp
, *dstlim
;
302 int n
, len
, checked
, l
;
308 dstlim
= dst
+ dstsiz
;
309 if (srcp
< msg
|| srcp
>= eom
) {
313 /* Fetch next label in domain name. */
314 while ((n
= *srcp
++) != 0) {
315 /* Check for indirection. */
316 switch (n
& NS_CMPRSFLGS
) {
320 if ((l
= labellen(srcp
- 1)) < 0) {
324 if (dstp
+ l
+ 1 >= dstlim
|| srcp
+ l
>= eom
) {
330 memcpy(dstp
, srcp
, l
);
341 len
= srcp
- src
+ 1;
342 srcp
= msg
+ (((n
& 0x3f) << 8) | (*srcp
& 0xff));
343 if (srcp
< msg
|| srcp
>= eom
) { /* Out of range. */
349 * Check for loops in the compressed name;
350 * if we've looked at the whole message,
351 * there must be a loop.
353 if (checked
>= eom
- msg
) {
361 return (-1); /* flag error */
371 * irc_ns_name_ntop(src, dst, dstsiz)
372 * Convert an encoded domain name to printable ascii as per RFC1035.
374 * Number of bytes written to buffer, or -1 (with errno set)
376 * The root is returned as "."
377 * All other domains are returned in non absolute form
380 irc_ns_name_ntop(const char *src
, char *dst
, size_t dstsiz
)
392 while ((n
= *cp
++) != 0) {
393 if ((n
& NS_CMPRSFLGS
) == NS_CMPRSFLGS
) {
394 /* Some kind of compression pointer. */
405 if ((l
= labellen((const unsigned char*)(cp
- 1))) < 0) {
406 errno
= EMSGSIZE
; /* XXX */
413 if ((n
& NS_CMPRSFLGS
) == NS_TYPE_ELT
) {
416 if (n
!= DNS_LABELTYPE_BITSTRING
) {
417 /* XXX: labellen should reject this case */
421 if ((m
= irc_decode_bitstring(&cp
, dn
, eom
)) < 0)
429 for ((void)NULL
; l
> 0; l
--) {
438 } else if (!printable(c
)) {
444 *dn
++ = digits
[c
/ 100];
445 *dn
++ = digits
[(c
% 100) / 10];
446 *dn
++ = digits
[c
% 10];
472 * Pack domain name 'exp_dn' in presentation form into 'comp_dn'.
473 * Return the size of the compressed name or -1.
474 * 'length' is the size of the array pointed to by 'comp_dn'.
477 irc_dn_comp(const char *src
, unsigned char *dst
, int dstsiz
,
478 const unsigned char **dnptrs
, const unsigned char **lastdnptr
)
480 return(irc_ns_name_compress(src
, dst
, (size_t)dstsiz
,
481 (const unsigned char **)dnptrs
,
482 (const unsigned char **)lastdnptr
));
486 * Skip over a compressed domain name. Return the size or -1.
489 irc_dn_skipname(const unsigned char *ptr
, const unsigned char *eom
) {
490 const unsigned char *saveptr
= ptr
;
492 if (irc_ns_name_skip(&ptr
, eom
) == -1)
494 return(ptr
- saveptr
);
498 * ns_name_skip(ptrptr, eom)
499 * Advance *ptrptr to skip over the compressed name it points at.
501 * 0 on success, -1 (with errno set) on failure.
504 irc_ns_name_skip(const unsigned char **ptrptr
, const unsigned char *eom
)
506 const unsigned char *cp
;
512 while (cp
< eom
&& (n
= *cp
++) != 0)
514 /* Check for indirection. */
515 switch (n
& NS_CMPRSFLGS
)
517 case 0: /* normal case, n == len */
520 case NS_TYPE_ELT
: /* EDNS0 extended label */
521 if ((l
= labellen(cp
- 1)) < 0)
523 errno
= EMSGSIZE
; /* XXX */
529 case NS_CMPRSFLGS
: /* indirection */
532 default: /* illegal type */
551 irc_ns_get16(const unsigned char *src
)
555 IRC_NS_GET16(dst
, src
);
560 irc_ns_get32(const unsigned char *src
)
564 IRC_NS_GET32(dst
, src
);
569 irc_ns_put16(unsigned int src
, unsigned char *dst
)
571 IRC_NS_PUT16(src
, dst
);
575 irc_ns_put32(unsigned long src
, unsigned char *dst
)
577 IRC_NS_PUT32(src
, dst
);
584 * Thinking in noninternationalized USASCII (per the DNS spec),
585 * is this characted special ("in need of quoting") ?
597 case 0x5C: /* '\\' */
600 /* Special modifiers in zone files. */
610 labellen(const unsigned char *lp
)
613 unsigned char l
= *lp
;
615 if ((l
& NS_CMPRSFLGS
) == NS_CMPRSFLGS
)
617 /* should be avoided by the caller */
621 if ((l
& NS_CMPRSFLGS
) == NS_TYPE_ELT
)
623 if (l
== DNS_LABELTYPE_BITSTRING
)
625 if ((bitlen
= *(lp
+ 1)) == 0)
627 return((bitlen
+ 7 ) / 8 + 1);
630 return(-1); /* unknwon ELT */
639 * Thinking in noninternationalized USASCII (per the DNS spec),
640 * is this character visible and not a space when printed ?
647 return(ch
> 0x20 && ch
< 0x7f);
651 irc_decode_bitstring(const char **cpp
, char *dn
, const char *eom
)
653 const char *cp
= *cpp
;
657 if ((blen
= (*cp
& 0xff)) == 0)
659 plen
= (blen
+ 3) / 4;
660 plen
+= sizeof("\\[x/]") + (blen
> 99 ? 3 : (blen
> 9) ? 2 : 1);
661 if (dn
+ plen
>= eom
)
665 dn
+= sprintf(dn
, "\\[x");
666 for (b
= blen
; b
> 7; b
-= 8, cp
++)
667 dn
+= sprintf(dn
, "%02x", *cp
& 0xff);
670 dn
+= sprintf(dn
, "%02x", tc
& (0xff << (8 - b
)));
673 dn
+= sprintf(dn
, "%1x",
674 ((tc
>> 4) & 0x0f) & (0x0f << (4 - b
)));
676 dn
+= sprintf(dn
, "/%d]", blen
);
683 * irc_ns_name_pton(src, dst, dstsiz)
684 * Convert a ascii string into an encoded domain name as per RFC1035.
687 * 1 if string was fully qualified
688 * 0 is string was not fully qualified
690 * Enforces label and domain length limits.
693 irc_ns_name_pton(const char *src
, unsigned char *dst
, size_t dstsiz
)
695 unsigned char *label
, *bp
, *eom
;
697 int c
, n
, escaped
, e
= 0;
705 while ((c
= *src
++) != 0) {
707 if (c
== '[') { /* start a bit string label */
708 if ((cp
= strchr(src
, ']')) == NULL
) {
709 errno
= EINVAL
; /* ??? */
712 if ((e
= irc_encode_bitsring(&src
,
723 if ((c
= *src
++) == 0)
731 else if ((cp
= strchr(digits
, c
)) != NULL
) {
732 n
= (cp
- digits
) * 100;
733 if ((c
= *src
++) == 0 ||
734 (cp
= strchr(digits
, c
)) == NULL
) {
738 n
+= (cp
- digits
) * 10;
739 if ((c
= *src
++) == 0 ||
740 (cp
= strchr(digits
, c
)) == NULL
) {
752 } else if (c
== '\\') {
755 } else if (c
== '.') {
756 c
= (bp
- label
- 1);
757 if ((c
& NS_CMPRSFLGS
) != 0) { /* Label too big. */
766 /* Fully qualified ? */
775 if ((bp
- dst
) > NS_MAXCDNAME
) {
781 if (c
== 0 || *src
== '.') {
792 *bp
++ = (unsigned char)c
;
794 c
= (bp
- label
- 1);
795 if ((c
& NS_CMPRSFLGS
) != 0) { /* Label too big. */
813 if ((bp
- dst
) > NS_MAXCDNAME
)
823 * irc_ns_name_pack(src, dst, dstsiz, dnptrs, lastdnptr)
824 * Pack domain name 'domain' into 'comp_dn'.
826 * Size of the compressed name, or -1.
828 * 'dnptrs' is an array of pointers to previous compressed names.
829 * dnptrs[0] is a pointer to the beginning of the message. The array
831 * 'lastdnptr' is a pointer to the end of the array pointed to
834 * The list of pointers in dnptrs is updated for labels inserted into
835 * the message as we compress the name. If 'dnptr' is NULL, we don't
836 * try to compress names. If 'lastdnptr' is NULL, we don't update the
840 irc_ns_name_pack(const unsigned char *src
, unsigned char *dst
, int dstsiz
,
841 const unsigned char **dnptrs
, const unsigned char **lastdnptr
)
844 const unsigned char **cpp
, **lpp
, *eob
, *msg
;
845 const unsigned char *srcp
;
852 if (dnptrs
!= NULL
) {
853 if ((msg
= *dnptrs
++) != NULL
) {
854 for (cpp
= dnptrs
; *cpp
!= NULL
; cpp
++)
856 lpp
= cpp
; /* end of list to search */
861 /* make sure the domain we are about to add is legal */
867 if ((n
& NS_CMPRSFLGS
) == NS_CMPRSFLGS
) {
871 if ((l0
= labellen(srcp
)) < 0) {
876 if (l
> NS_MAXCDNAME
) {
883 /* from here on we need to reset compression pointer array on error */
886 /* Look to see if we can use pointers. */
888 if (n
!= 0 && msg
!= NULL
) {
889 l
= irc_dn_find(srcp
, msg
, (const unsigned char * const *)dnptrs
,
890 (const unsigned char * const *)lpp
);
892 if (dstp
+ 1 >= eob
) {
895 *dstp
++ = (l
>> 8) | NS_CMPRSFLGS
;
899 /* Not found, save it. */
900 if (lastdnptr
!= NULL
&& cpp
< lastdnptr
- 1 &&
901 (dstp
- msg
) < 0x4000 && first
) {
907 /* copy label to buffer */
908 if ((n
& NS_CMPRSFLGS
) == NS_CMPRSFLGS
) {
909 /* Should not happen. */
913 if (dstp
+ 1 + n
>= eob
) {
916 memcpy(dstp
, srcp
, n
+ 1);
932 irc_ns_name_compress(const char *src
, unsigned char *dst
, size_t dstsiz
,
933 const unsigned char **dnptrs
, const unsigned char **lastdnptr
)
935 unsigned char tmp
[NS_MAXCDNAME
];
937 if (irc_ns_name_pton(src
, tmp
, sizeof tmp
) == -1)
939 return(irc_ns_name_pack(tmp
, dst
, dstsiz
, dnptrs
, lastdnptr
));
943 irc_encode_bitsring(const char **bp
, const char *end
, unsigned char **labelp
,
944 unsigned char **dst
, const char *eom
)
947 const char *cp
= *bp
;
949 const char *beg_blen
;
950 char *end_blen
= NULL
;
951 int value
= 0, count
= 0, tbcount
= 0, blen
= 0;
953 beg_blen
= end_blen
= NULL
;
955 /* a bitstring must contain at least 2 characters */
959 /* XXX: currently, only hex strings are supported */
962 if (!isxdigit((*cp
) & 0xff)) /* reject '\[x/BLEN]' */
965 for (tp
= (char*)(dst
+ 1); cp
< end
&& tp
< eom
; cp
++) {
967 case ']': /* end of the bitstring */
969 if (beg_blen
== NULL
)
971 blen
= (int)strtol(beg_blen
, &end_blen
, 10);
972 if (*end_blen
!= ']')
976 *tp
++ = ((value
<< 4) & 0xff);
984 if (!isdigit(c
&0xff))
986 if (beg_blen
== NULL
) {
989 /* blen never begings with 0 */
995 if (!isxdigit(c
&0xff))
998 value
+= digitvalue
[(int)c
];
1012 if (cp
>= end
|| tp
>= eom
)
1016 * bit length validation:
1017 * If a <length> is present, the number of digits in the <bit-data>
1018 * MUST be just sufficient to contain the number of bits specified
1019 * by the <length>. If there are insignificant bits in a final
1020 * hexadecimal or octal digit, they MUST be zero.
1021 * RFC 2673, Section 3.2.
1026 if (((blen
+ 3) & ~3) != tbcount
)
1028 traillen
= tbcount
- blen
; /* between 0 and 3 */
1029 if (((value
<< (8 - traillen
)) & 0xff) != 0)
1037 /* encode the type and the significant bit fields */
1038 **labelp
= DNS_LABELTYPE_BITSTRING
;
1042 *dst
= (unsigned char*)tp
;
1048 * dn_find(domain, msg, dnptrs, lastdnptr)
1049 * Search for the counted-label name in an array of compressed names.
1051 * offset from msg if found, or -1.
1053 * dnptrs is the pointer to the first name on the list,
1054 * not the pointer to the start of the message.
1057 irc_dn_find(const unsigned char *domain
, const unsigned char *msg
,
1058 const unsigned char * const *dnptrs
,
1059 const unsigned char * const *lastdnptr
)
1061 const unsigned char *dn
, *cp
, *sp
;
1062 const unsigned char * const *cpp
;
1065 for (cpp
= dnptrs
; cpp
< lastdnptr
; cpp
++)
1069 * terminate search on:
1071 * compression pointer
1074 while (*sp
!= 0 && (*sp
& NS_CMPRSFLGS
) == 0 &&
1075 (sp
- msg
) < 0x4000) {
1078 while ((n
= *cp
++) != 0) {
1080 * check for indirection
1082 switch (n
& NS_CMPRSFLGS
) {
1083 case 0: /* normal case, n == len */
1084 n
= labellen(cp
- 1); /* XXX */
1089 for ((void)NULL
; n
> 0; n
--)
1090 if (mklower(*dn
++) !=
1093 /* Is next root for both ? */
1094 if (*dn
== '\0' && *cp
== '\0')
1099 case NS_CMPRSFLGS
: /* indirection */
1100 cp
= msg
+ (((n
& 0x3f) << 8) | *cp
);
1103 default: /* illegal type */
1117 * * Thinking in noninternationalized USASCII (per the DNS spec),
1118 * * convert this character to lower case if it's upper case.
1123 if (ch
>= 0x41 && ch
<= 0x5A)
1129 /* From resolv/mkquery.c */
1132 * Form all types of queries.
1133 * Returns the size of the result or -1.
1137 const char *dname
, /* domain name */
1138 int class, int type
, /* class and type of query */
1139 unsigned char *buf
, /* buffer to put query */
1140 int buflen
) /* size of buffer */
1145 const unsigned char *dnptrs
[20], **dpp
, **lastdnptr
;
1148 * Initialize header fields.
1150 if ((buf
== NULL
) || (buflen
< HFIXEDSZ
))
1152 memset(buf
, 0, HFIXEDSZ
);
1153 hp
= (HEADER
*)(void *)buf
;
1157 hp
->rd
= 1; /* recurse */
1158 hp
->rcode
= NO_ERRORS
;
1159 cp
= buf
+ HFIXEDSZ
;
1164 lastdnptr
= dnptrs
+ sizeof dnptrs
/ sizeof dnptrs
[0];
1166 if ((buflen
-= QFIXEDSZ
) < 0)
1168 if ((n
= irc_dn_comp(dname
, cp
, buflen
, dnptrs
, lastdnptr
)) < 0)
1173 IRC_NS_PUT16(type
, cp
);
1174 IRC_NS_PUT16(class, cp
);
1175 hp
->qdcount
= htons(1);