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 adns_status adns__findrr_anychk(adns_query qu, int serv,
165 const byte *dgram, int dglen, int *cbyte_io,
166 int *type_r, int *class_r,
167 unsigned long *ttl_r,
168 int *rdlen_r, int *rdstart_r,
169 const byte *eo_dgram, int eo_dglen,
170 int eo_cbyte, int *eo_matched_r) {
171 findlabel_state fls, eo_fls_buf;
172 findlabel_state *eo_fls; /* 0 iff we know it's not matching eo_... */
177 int lablen, labstart, ch;
178 int eo_lablen, eo_labstart, eo_ch;
183 adns__findlabel_start(&fls,qu->ads, serv,qu, dgram,dglen,dglen,cbyte,&cbyte);
186 adns__findlabel_start(eo_fls,qu->ads, -1,0,
187 eo_dgram,eo_dglen,eo_dglen,eo_cbyte,0);
193 st= adns__findlabel_next(&fls,&lablen,&labstart);
195 if (lablen<0) goto x_truncated;
198 st= adns__findlabel_next(eo_fls,&eo_lablen,&eo_labstart);
199 assert(!st); assert(eo_lablen>=0);
200 if (lablen != eo_lablen) eo_fls= 0;
201 while (eo_fls && eo_lablen-- > 0) {
202 ch= dgram[labstart++]; if (ctype_alpha(ch)) ch &= ~32;
203 eo_ch= eo_dgram[eo_labstart++]; if (ctype_alpha(eo_ch)) eo_ch &= ~32;
204 if (ch != eo_ch) eo_fls= 0;
209 if (eo_matched_r) *eo_matched_r= !!eo_fls;
211 if (cbyte+10>dglen) goto x_truncated;
212 GET_W(cbyte,tmp); *type_r= tmp;
213 GET_W(cbyte,tmp); *class_r= tmp;
216 if (ttl > MAXTTLBELIEVE) ttl= MAXTTLBELIEVE;
219 GET_W(cbyte,rdlen); if (rdlen_r) *rdlen_r= rdlen;
220 if (rdstart_r) *rdstart_r= cbyte;
222 if (cbyte>dglen) goto x_truncated;
231 adns_status adns__findrr(adns_query qu, int serv,
232 const byte *dgram, int dglen, int *cbyte_io,
233 int *type_r, int *class_r, unsigned long *ttl_r,
234 int *rdlen_r, int *rdstart_r,
235 int *ownermatchedquery_r) {
236 if (!ownermatchedquery_r) {
237 return adns__findrr_anychk(qu,serv,
238 dgram,dglen,cbyte_io,
239 type_r,class_r,ttl_r,rdlen_r,rdstart_r,
241 } else if (!qu->cname_dgram) {
242 return adns__findrr_anychk(qu,serv,
243 dgram,dglen,cbyte_io,
244 type_r,class_r,ttl_r,rdlen_r,rdstart_r,
245 qu->query_dgram,qu->query_dglen,DNS_HDRSIZE,
246 ownermatchedquery_r);
248 return adns__findrr_anychk(qu,serv,
249 dgram,dglen,cbyte_io,
250 type_r,class_r,ttl_r,rdlen_r,rdstart_r,
251 qu->cname_dgram,qu->cname_dglen,qu->cname_begin,
252 ownermatchedquery_r);