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// -*-c++-*-
/* $Id$ */
/*
*
* Copyright (C) 1998-2003 David Mazieres (dm@uun.org)
*
* 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
*
*/
#ifndef _DNSPARSE_H_
#define _DNSPARSE_H_ 1
#include "dns.h"
#include "qhash.h"
#define QBSIZE 512
#ifndef T_DNAME
# define T_DNAME 39
#endif /* !T_DNAME */
#ifndef T_SRV
# define T_SRV 33
#endif /* !T_SRV */
#ifndef MAXDNAME
# define MAXDNAME 1025
#endif /* !MAXDNAME */
class dnstcppkt {
u_int inbufsize;
u_int inbufpos;
u_int inbufused;
u_char *inbuf;
suio outbuf;
void compact ();
u_int pktsize ()
{ return inbufpos < inbufused + 2 ? 2 : getshort (inbuf + inbufused) + 2; }
public:
dnstcppkt ();
~dnstcppkt ();
void reset ();
int input (int fd); // Returns size of packet, 0 incomplete, -1 err
int output (int fd); // 1 drained, 0 need again, -1 err
bool getpkt (u_char **pp, size_t *sp);
void putpkt (const u_char *p, size_t s);
};
class nameset {
typedef qhash<str, u_int> map_t;
u_int pos;
map_t name2pos;
public:
nameset () : pos (0) {}
char *store (str s);
char *lookup (str s) const;
bool present (str s) const { return name2pos[s]; }
static char *xlat (char *base, char *p) { return base + (p - (char *) 0); }
u_int size () const { return pos; }
void put (char *dst) const;
};
struct resrec {
struct rd_mx {
u_int16_t mx_pref;
char mx_exch[MAXDNAME];
};
struct rd_soa {
char soa_mname[MAXDNAME];
char soa_rname[MAXDNAME];
u_int32_t soa_serial;
u_int32_t soa_refresh;
u_int32_t soa_retry;
u_int32_t soa_expire;
u_int32_t soa_minimum;
};
struct rd_srv {
u_int16_t srv_prio;
u_int16_t srv_weight;
u_int16_t srv_port;
char srv_target[MAXDNAME];
};
char rr_name[MAXDNAME];
u_int16_t rr_class;
u_int16_t rr_type;
u_int32_t rr_ttl;
u_int16_t rr_rdlen;
union {
char rr_ns[MAXDNAME];
in_addr rr_a;
char rr_cname[MAXDNAME];
rd_soa rr_soa;
char rr_ptr[MAXDNAME];
rd_mx rr_mx;
char rr_txt[sizeof (rd_soa)];
rd_srv rr_srv;
};
};
struct question {
char q_name[MAXDNAME];
u_int16_t q_class;
u_int16_t q_type;
};
class dnsparse {
dnsparse ();
const u_char *const buf;
const u_char *const eom;
const u_char *anp;
static int mxrec_cmp (const void *, const void *);
static int srvrec_cmp (const void *, const void *);
static void srvrec_randomize (srvrec *base, srvrec *last);
static size_t hintsize (u_int nhints)
{ return nhints * sizeof (addrhint) + (nhints+1) * sizeof (addrhint *); }
static addrhint **puthints (char *dst, const vec<addrhint> &hv,
char *namebase);
bool gethints (vec<addrhint> *hv, const nameset &nset);
public:
int error;
const HEADER *const hdr;
const u_int ancount;
const u_int nscount;
const u_int arcount;
dnsparse (const u_char *buf, size_t len, bool answer = true);
const u_char *getqp () { return hdr ? buf + sizeof (HEADER) : NULL; }
const u_char *getanp () { return anp; }
bool qparse (question *);
bool qparse (const u_char **, question *);
bool rrparse (const u_char **, resrec *);
bool skipnrecs (const u_char **, u_int);
ptr<hostent> tohostent ();
ptr<mxlist> tomxlist ();
ptr<srvlist> tosrvlist ();
ptr<txtlist> totxtlist ();
};
#endif /* !_DNSPARSE_H_ */
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