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NeoStats/adns/parse.c
2004-01-14 11:36:37 +00:00

332 lines
8.2 KiB
C

/* NeoStats - IRC Statistical Services
** Copyright (c) 1999-2004 Adam Rutter, Justin Hammond
** http://www.neostats.net/
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
** USA
**
** NeoStats CVS Identification
** $Id$
*/
/*
* parse.c
* - parsing assistance functions (mainly for domains inside datagrams)
*/
/*
* This file is
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
*
* It is part of adns, which is
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
* Copyright (C) 1999-2000 Tony Finch <dot@dotat.at>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include "internal.h"
int vbuf__append_quoted1035(vbuf * vb, const byte * buf, int len)
{
char qbuf[10];
int i, ch;
while (len) {
qbuf[0] = 0;
for (i = 0; i < len; i++) {
ch = buf[i];
if (ch <= ' ' || ch >= 127) {
sprintf(qbuf, "\\%03o", ch);
break;
} else if (!ctype_domainunquoted(ch)) {
sprintf(qbuf, "\\%c", ch);
break;
}
}
if (!adns__vbuf_append(vb, buf, i)
|| !adns__vbuf_append(vb, qbuf, strlen(qbuf)))
return 0;
if (i < len)
i++;
buf += i;
len -= i;
}
return 1;
}
void adns__findlabel_start(findlabel_state * fls, adns_state ads,
int serv, adns_query qu,
const byte * dgram, int dglen, int max,
int dmbegin, int *dmend_rlater)
{
fls->ads = ads;
fls->qu = qu;
fls->serv = serv;
fls->dgram = dgram;
fls->dglen = dglen;
fls->max = max;
fls->cbyte = dmbegin;
fls->namelen = 0;
fls->dmend_r = dmend_rlater;
}
adns_status adns__findlabel_next(findlabel_state * fls,
int *lablen_r, int *labstart_r)
{
int lablen, jumpto;
const char *dgram;
dgram = fls->dgram;
for (;;) {
if (fls->cbyte >= fls->dglen)
goto x_truncated;
if (fls->cbyte >= fls->max)
goto x_badresponse;
GET_B(fls->cbyte, lablen);
if (!(lablen & 0x0c0))
break;
if ((lablen & 0x0c0) != 0x0c0)
return adns_s_unknownformat;
if (fls->cbyte >= fls->dglen)
goto x_truncated;
if (fls->cbyte >= fls->max)
goto x_badresponse;
GET_B(fls->cbyte, jumpto);
jumpto |= (lablen & 0x3f) << 8;
if (fls->dmend_r)
*(fls->dmend_r) = fls->cbyte;
fls->cbyte = jumpto;
fls->dmend_r = 0;
fls->max = fls->dglen + 1;
}
if (labstart_r)
*labstart_r = fls->cbyte;
if (lablen) {
if (fls->namelen)
fls->namelen++;
fls->namelen += lablen;
if (fls->namelen > DNS_MAXDOMAIN)
return adns_s_answerdomaintoolong;
fls->cbyte += lablen;
if (fls->cbyte > fls->dglen)
goto x_truncated;
if (fls->cbyte > fls->max)
goto x_badresponse;
} else {
if (fls->dmend_r)
*(fls->dmend_r) = fls->cbyte;
}
*lablen_r = lablen;
return adns_s_ok;
x_truncated:
*lablen_r = -1;
return adns_s_ok;
x_badresponse:
adns__diag(fls->ads, fls->serv, fls->qu,
"label in domain runs beyond end of domain");
return adns_s_invalidresponse;
}
adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu,
vbuf * vb, adns_queryflags flags,
const byte * dgram, int dglen,
int *cbyte_io, int max)
{
findlabel_state fls;
adns__findlabel_start(&fls, ads, serv, qu, dgram, dglen, max,
*cbyte_io, cbyte_io);
vb->used = 0;
return adns__parse_domain_more(&fls, ads, qu, vb, flags, dgram);
}
adns_status adns__parse_domain_more(findlabel_state * fls, adns_state ads,
adns_query qu, vbuf * vb,
parsedomain_flags flags,
const byte * dgram)
{
int lablen, labstart, i, ch, first;
adns_status st;
first = 1;
for (;;) {
st = adns__findlabel_next(fls, &lablen, &labstart);
if (st)
return st;
if (lablen < 0) {
vb->used = 0;
return adns_s_ok;
}
if (!lablen)
break;
if (first) {
first = 0;
} else {
if (!adns__vbuf_append(vb, ".", 1))
return adns_s_nomemory;
}
if (flags & pdf_quoteok) {
if (!vbuf__append_quoted1035
(vb, dgram + labstart, lablen))
return adns_s_nomemory;
} else {
ch = dgram[labstart];
if (!ctype_alpha(ch) && !ctype_digit(ch))
return adns_s_answerdomaininvalid;
for (i = labstart + 1; i < labstart + lablen; i++) {
ch = dgram[i];
if (ch != '-' && !ctype_alpha(ch)
&& !ctype_digit(ch))
return adns_s_answerdomaininvalid;
}
if (!adns__vbuf_append
(vb, dgram + labstart, lablen))
return adns_s_nomemory;
}
}
if (!adns__vbuf_append(vb, "", 1))
return adns_s_nomemory;
return adns_s_ok;
}
adns_status adns__findrr_anychk(adns_query qu, int serv,
const byte * dgram, int dglen,
int *cbyte_io, int *type_r, int *class_r,
unsigned long *ttl_r, int *rdlen_r,
int *rdstart_r, const byte * eo_dgram,
int eo_dglen, int eo_cbyte,
int *eo_matched_r)
{
findlabel_state fls, eo_fls;
int cbyte;
int tmp, rdlen, mismatch;
unsigned long ttl;
int lablen, labstart, ch;
int eo_lablen, eo_labstart, eo_ch;
adns_status st;
cbyte = *cbyte_io;
adns__findlabel_start(&fls, qu->ads, serv, qu, dgram, dglen, dglen,
cbyte, &cbyte);
if (eo_dgram) {
adns__findlabel_start(&eo_fls, qu->ads, -1, 0, eo_dgram,
eo_dglen, eo_dglen, eo_cbyte, 0);
mismatch = 0;
} else {
mismatch = 1;
}
for (;;) {
st = adns__findlabel_next(&fls, &lablen, &labstart);
if (st)
return st;
if (lablen < 0)
goto x_truncated;
if (!mismatch) {
st = adns__findlabel_next(&eo_fls, &eo_lablen,
&eo_labstart);
assert(!st);
assert(eo_lablen >= 0);
if (lablen != eo_lablen)
mismatch = 1;
while (!mismatch && eo_lablen-- > 0) {
ch = dgram[labstart++];
if (ctype_alpha(ch))
ch &= ~32;
eo_ch = eo_dgram[eo_labstart++];
if (ctype_alpha(eo_ch))
eo_ch &= ~32;
if (ch != eo_ch)
mismatch = 1;
}
}
if (!lablen)
break;
}
if (eo_matched_r)
*eo_matched_r = !mismatch;
if (cbyte + 10 > dglen)
goto x_truncated;
GET_W(cbyte, tmp);
*type_r = tmp;
GET_W(cbyte, tmp);
*class_r = tmp;
GET_L(cbyte, ttl);
if (ttl > MAXTTLBELIEVE)
ttl = MAXTTLBELIEVE;
*ttl_r = ttl;
GET_W(cbyte, rdlen);
if (rdlen_r)
*rdlen_r = rdlen;
if (rdstart_r)
*rdstart_r = cbyte;
cbyte += rdlen;
if (cbyte > dglen)
goto x_truncated;
*cbyte_io = cbyte;
return adns_s_ok;
x_truncated:
*type_r = -1;
return 0;
}
adns_status adns__findrr(adns_query qu, int serv,
const byte * dgram, int dglen, int *cbyte_io,
int *type_r, int *class_r, unsigned long *ttl_r,
int *rdlen_r, int *rdstart_r,
int *ownermatchedquery_r)
{
if (!ownermatchedquery_r) {
return adns__findrr_anychk(qu, serv,
dgram, dglen, cbyte_io,
type_r, class_r, ttl_r, rdlen_r,
rdstart_r, 0, 0, 0, 0);
} else if (!qu->cname_dgram) {
return adns__findrr_anychk(qu, serv,
dgram, dglen, cbyte_io,
type_r, class_r, ttl_r, rdlen_r,
rdstart_r, qu->query_dgram,
qu->query_dglen, DNS_HDRSIZE,
ownermatchedquery_r);
} else {
return adns__findrr_anychk(qu, serv,
dgram, dglen, cbyte_io,
type_r, class_r, ttl_r, rdlen_r,
rdstart_r, qu->cname_dgram,
qu->cname_dglen,
qu->cname_begin,
ownermatchedquery_r);
}
}