3 * - parsing assistance functions (mainly for domains inside datagrams)
6 * This file is part of adns, which is
7 * Copyright (C) 1997-2000,2003,2006 Ian Jackson
8 * Copyright (C) 1999-2000,2003,2006 Tony Finch
9 * Copyright (C) 1991 Massachusetts Institute of Technology
10 * (See the file INSTALL for full details.)
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2, or (at your option)
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software Foundation,
24 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 int vbuf__append_quoted1035(vbuf
*vb
, const byte
*buf
, int len
) {
35 for (i
=0; i
<len
; i
++) {
37 if (ch
<= ' ' || ch
>= 127) {
38 sprintf(qbuf
,"\\%03o",ch
);
40 } else if (!ctype_domainunquoted(ch
)) {
41 sprintf(qbuf
,"\\%c",ch
);
45 if (!adns__vbuf_append(vb
,buf
,i
) ||
46 !adns__vbuf_append(vb
,qbuf
,strlen(qbuf
)))
55 void adns__findlabel_start(findlabel_state
*fls
, adns_state ads
,
56 int serv
, adns_query qu
,
57 const byte
*dgram
, int dglen
, int max
,
58 int dmbegin
, int *dmend_rlater
) {
67 fls
->dmend_r
= dmend_rlater
;
70 adns_status
adns__findlabel_next(findlabel_state
*fls
,
71 int *lablen_r
, int *labstart_r
) {
77 if (fls
->cbyte
>= fls
->dglen
) goto x_truncated
;
78 if (fls
->cbyte
>= fls
->max
) goto x_badresponse
;
79 GET_B(fls
->cbyte
,lablen
);
80 if (!(lablen
& 0x0c0)) break;
81 if ((lablen
& 0x0c0) != 0x0c0) return adns_s_unknownformat
;
82 if (fls
->cbyte
>= fls
->dglen
) goto x_truncated
;
83 if (fls
->cbyte
>= fls
->max
) goto x_badresponse
;
84 GET_B(fls
->cbyte
,jumpto
);
85 jumpto
|= (lablen
&0x3f)<<8;
86 if (fls
->dmend_r
) *(fls
->dmend_r
)= fls
->cbyte
;
88 fls
->dmend_r
= 0; fls
->max
= fls
->dglen
+1;
90 if (labstart_r
) *labstart_r
= fls
->cbyte
;
92 if (fls
->namelen
) fls
->namelen
++;
93 fls
->namelen
+= lablen
;
94 if (fls
->namelen
> DNS_MAXDOMAIN
) return adns_s_answerdomaintoolong
;
96 if (fls
->cbyte
> fls
->dglen
) goto x_truncated
;
97 if (fls
->cbyte
> fls
->max
) goto x_badresponse
;
99 if (fls
->dmend_r
) *(fls
->dmend_r
)= fls
->cbyte
;
109 adns__diag(fls
->ads
,fls
->serv
,fls
->qu
,
110 "label in domain runs beyond end of domain");
111 return adns_s_invalidresponse
;
114 adns_status
adns__parse_domain(adns_state ads
, int serv
, adns_query qu
,
115 vbuf
*vb
, parsedomain_flags flags
,
116 const byte
*dgram
, int dglen
, int *cbyte_io
,
120 adns__findlabel_start(&fls
,ads
, serv
,qu
, dgram
,dglen
,max
,
123 return adns__parse_domain_more(&fls
,ads
,qu
, vb
,flags
,dgram
);
126 adns_status
adns__parse_domain_more(findlabel_state
*fls
, adns_state ads
,
127 adns_query qu
, vbuf
*vb
,
128 parsedomain_flags flags
,
130 int lablen
, labstart
, i
, ch
, first
;
135 st
= adns__findlabel_next(fls
,&lablen
,&labstart
);
137 if (lablen
<0) { vb
->used
=0; return adns_s_ok
; }
142 if (!adns__vbuf_append(vb
,".",1)) return adns_s_nomemory
;
144 if (flags
& pdf_quoteok
) {
145 if (!vbuf__append_quoted1035(vb
,dgram
+labstart
,lablen
))
146 return adns_s_nomemory
;
149 if (!ctype_alpha(ch
) && !ctype_digit(ch
))
150 return adns_s_answerdomaininvalid
;
151 for (i
= labstart
+1; i
<labstart
+lablen
; i
++) {
153 if (ch
!= '-' && !ctype_alpha(ch
) && !ctype_digit(ch
))
154 return adns_s_answerdomaininvalid
;
156 if (!adns__vbuf_append(vb
,dgram
+labstart
,lablen
))
157 return adns_s_nomemory
;
160 if (!adns__vbuf_append(vb
,"",1)) return adns_s_nomemory
;
164 bool adns__labels_equal(const byte
*a
, int al
, const byte
*b
, int bl
) {
165 if (al
!= bl
) return 0;
167 int ac
= ctype_toupper(*a
++);
168 int bc
= ctype_toupper(*b
++);
169 if (ac
!= bc
) return 0;
174 adns_status
adns__findrr_anychk(adns_query qu
, int serv
,
175 const byte
*dgram
, int dglen
, int *cbyte_io
,
176 int *type_r
, int *class_r
,
177 unsigned long *ttl_r
,
178 int *rdlen_r
, int *rdstart_r
,
179 const byte
*eo_dgram
, int eo_dglen
,
180 int eo_cbyte
, int *eo_matched_r
) {
181 findlabel_state fls
, eo_fls_buf
;
182 findlabel_state
*eo_fls
; /* 0 iff we know it's not matching eo_... */
187 int lablen
, labstart
;
188 int eo_lablen
, eo_labstart
;
193 adns__findlabel_start(&fls
,qu
->ads
, serv
,qu
, dgram
,dglen
,dglen
,cbyte
,&cbyte
);
196 adns__findlabel_start(eo_fls
,qu
->ads
, -1,0,
197 eo_dgram
,eo_dglen
,eo_dglen
,eo_cbyte
,0);
203 st
= adns__findlabel_next(&fls
,&lablen
,&labstart
);
205 if (lablen
<0) goto x_truncated
;
208 st
= adns__findlabel_next(eo_fls
,&eo_lablen
,&eo_labstart
);
209 assert(!st
); assert(eo_lablen
>=0);
210 if (!adns__labels_equal(dgram
+labstart
, lablen
,
211 eo_dgram
+eo_labstart
, eo_lablen
))
216 if (eo_matched_r
) *eo_matched_r
= !!eo_fls
;
218 if (cbyte
+10>dglen
) goto x_truncated
;
219 GET_W(cbyte
,tmp
); *type_r
= tmp
;
220 GET_W(cbyte
,tmp
); *class_r
= tmp
;
223 if (ttl
> MAXTTLBELIEVE
) ttl
= MAXTTLBELIEVE
;
226 GET_W(cbyte
,rdlen
); if (rdlen_r
) *rdlen_r
= rdlen
;
227 if (rdstart_r
) *rdstart_r
= cbyte
;
229 if (cbyte
>dglen
) goto x_truncated
;
238 adns_status
adns__findrr(adns_query qu
, int serv
,
239 const byte
*dgram
, int dglen
, int *cbyte_io
,
240 int *type_r
, int *class_r
, unsigned long *ttl_r
,
241 int *rdlen_r
, int *rdstart_r
,
242 int *ownermatchedquery_r
) {
243 if (!ownermatchedquery_r
) {
244 return adns__findrr_anychk(qu
,serv
,
245 dgram
,dglen
,cbyte_io
,
246 type_r
,class_r
,ttl_r
,rdlen_r
,rdstart_r
,
248 } else if (!qu
->cname_dgram
) {
249 return adns__findrr_anychk(qu
,serv
,
250 dgram
,dglen
,cbyte_io
,
251 type_r
,class_r
,ttl_r
,rdlen_r
,rdstart_r
,
252 qu
->query_dgram
,qu
->query_dglen
,DNS_HDRSIZE
,
253 ownermatchedquery_r
);
255 return adns__findrr_anychk(qu
,serv
,
256 dgram
,dglen
,cbyte_io
,
257 type_r
,class_r
,ttl_r
,rdlen_r
,rdstart_r
,
258 qu
->cname_dgram
,qu
->cname_dglen
,qu
->cname_begin
,
259 ownermatchedquery_r
);