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/*
** Copyright 1998 - 2006 Double Precision, Inc.
** See COPYING for distribution information.
*/
#include "config.h"
#include "rfc1035.h"
#include <stdio.h>
#include <string.h>
#include "soxwrap/soxwrap.h"
#include <sys/types.h>
#include <arpa/inet.h>
#include <errno.h>
#include <stdlib.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if TIME_WITH_SYS_TIME
#include <sys/time.h>
#include <time.h>
#else
#if HAVE_SYS_TIME_H
#include <sys/time.h>
#else
#include <time.h>
#endif
#endif
#include "rfc1035_res.h"
int rfc1035_open_udp(int *af)
{
return (rfc1035_mksocket(SOCK_DGRAM, 0, af));
}
int rfc1035_send_udp(int fd, const struct sockaddr *sin, int sin_len,
const char *query, unsigned query_len)
{
if (sox_sendto(fd, (const char *)query, query_len, 0,
sin, sin_len) == query_len)
return (0);
return (-1);
}
static int dorecv(int fd, char *bufptr, int buflen, int flags,
struct sockaddr *addr, socklen_t *addrlen)
{
socklen_t len;
do
{
len=sox_recvfrom(fd, bufptr, buflen, flags, addr, addrlen);
} while (len < 0 && errno == EINTR);
return (len);
}
char *rfc1035_recv_udp(int fd,
const struct sockaddr *addrshouldfrom, int addrshouldfrom_len,
int *buflen, const char *query)
{
int len;
#if RFC1035_IPV6
struct sockaddr_storage addrfrom;
#else
struct sockaddr_in addrfrom;
#endif
socklen_t addrfromlen;
char rfc1035_buf[512];
char *bufptr=rfc1035_buf;
char *mallocedbuf=0;
*buflen=sizeof(rfc1035_buf);
while ((len=dorecv(fd, bufptr, *buflen, MSG_PEEK, 0, 0)) >= *buflen )
{
if (len == *buflen) len += 511;
++len;
if (mallocedbuf) free(mallocedbuf);
mallocedbuf=(char *)malloc(len);
if (!mallocedbuf) return (0);
bufptr= mallocedbuf;
*buflen=len;
}
addrfromlen=sizeof(addrfrom);
if (len < 0 || (len=dorecv(fd, bufptr, *buflen, 0,
(struct sockaddr *)&addrfrom, &addrfromlen)) < 0)
{
if (mallocedbuf)
free(mallocedbuf);
errno=EIO;
return (0);
}
*buflen=len;
if ( !rfc1035_same_ip( &addrfrom, addrfromlen,
addrshouldfrom, addrshouldfrom_len))
{
if (mallocedbuf)
free(mallocedbuf);
errno=EAGAIN;
return (0);
}
if ( *buflen < 2)
{
if (mallocedbuf)
free(mallocedbuf);
errno=EIO;
return (0);
}
if ( query && (bufptr[0] != query[0] || bufptr[1] != query[1]
|| (unsigned char)(bufptr[2] & 0x80) == 0 ))
{
if (mallocedbuf)
free(mallocedbuf);
errno=EAGAIN;
return (0);
}
if (!mallocedbuf)
{
if ((mallocedbuf=malloc( *buflen )) == 0)
return (0);
memcpy(mallocedbuf, bufptr, *buflen);
bufptr=mallocedbuf;
}
return (bufptr);
}
char *rfc1035_query_udp(struct rfc1035_res *res,
int fd, const struct sockaddr *sin, int sin_len,
const char *query, unsigned query_len, int *buflen, unsigned w)
{
time_t current_time, final_time;
char *rc;
time(¤t_time);
if (rfc1035_send_udp(fd, sin, sin_len, query, query_len))
return (0);
final_time=current_time+w;
while (current_time < final_time)
{
if (rfc1035_wait_reply(fd, final_time-current_time))
break;
rc=rfc1035_recv_udp(fd, sin, sin_len, buflen, query);
if (rc) return (rc);
if (errno != EAGAIN) break;
time(¤t_time);
}
errno=EAGAIN;
return (0);
}
