900 lines
20 KiB
C
Executable file
900 lines
20 KiB
C
Executable file
/*
|
|
* Copyright (c) 1985, 1989 Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
static char sccsid[] = "@(#)res_send.c 6.27 (Berkeley) 2/24/91";
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
/*
|
|
* Send query to name server and wait for reply.
|
|
*/
|
|
|
|
#if !_MINIX
|
|
#include <sys/param.h>
|
|
#include <sys/time.h>
|
|
#include <sys/socket.h>
|
|
#include <sys/uio.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/nameser.h>
|
|
#include <stdio.h>
|
|
#include <errno.h>
|
|
#include <resolv.h>
|
|
#include <unistd.h>
|
|
#include <string.h>
|
|
|
|
#else /* _MINIX */
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/select.h>
|
|
#include <sys/stat.h>
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <signal.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#include <net/hton.h>
|
|
|
|
#include <net/netlib.h>
|
|
#include <net/gen/in.h>
|
|
#include <net/gen/inet.h>
|
|
#include <net/gen/netdb.h>
|
|
#include <net/gen/nameser.h>
|
|
#include <net/gen/resolv.h>
|
|
#include <net/gen/tcp.h>
|
|
#include <net/gen/tcp_io.h>
|
|
#include <net/gen/udp.h>
|
|
#include <net/gen/udp_hdr.h>
|
|
#include <net/gen/udp_io.h>
|
|
|
|
static int tcp_connect _ARGS(( ipaddr_t host, Tcpport_t port, int *terrno ));
|
|
static int tcpip_writeall _ARGS(( int fd, const char *buf, size_t siz ));
|
|
static int udp_connect _ARGS(( void ));
|
|
static int udp_sendto _ARGS(( int fd, const char *buf, unsigned buflen,
|
|
ipaddr_t addr, Udpport_t port ));
|
|
static int udp_receive _ARGS(( int fd, char *buf, unsigned buflen,
|
|
time_t timeout ));
|
|
|
|
#endif /* !_MINIX */
|
|
|
|
static int s = -1; /* socket used for communications */
|
|
#if !_MINIX
|
|
static struct sockaddr no_addr;
|
|
|
|
#ifndef FD_SET
|
|
#define NFDBITS 32
|
|
#define FD_SETSIZE 32
|
|
#define FD_SET(n, p) ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
|
|
#define FD_CLR(n, p) ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
|
|
#define FD_ISSET(n, p) ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
|
|
#define FD_ZERO(p) bzero((char *)(p), sizeof(*(p)))
|
|
#endif /* FD_SET */
|
|
#endif /* _MINIX */
|
|
|
|
res_send(buf, buflen, answer, anslen)
|
|
const char *buf;
|
|
int buflen;
|
|
char *answer;
|
|
int anslen;
|
|
{
|
|
register int n;
|
|
int try, v_circuit, resplen, ns;
|
|
int gotsomewhere = 0, connected = 0;
|
|
int connreset = 0;
|
|
#if !_MINIX
|
|
u_short id, len;
|
|
#else /* _MINIX */
|
|
u16_t id, len;
|
|
#endif /* !_MINIX */
|
|
char *cp;
|
|
#if !_MINIX
|
|
fd_set dsmask;
|
|
struct timeval timeout;
|
|
HEADER *hp = (HEADER *) buf;
|
|
HEADER *anhp = (HEADER *) answer;
|
|
struct iovec iov[2];
|
|
#else /* _MINIX */
|
|
time_t timeout;
|
|
dns_hdr_t *hp = (dns_hdr_t *) buf;
|
|
dns_hdr_t *anhp = (dns_hdr_t *) answer;
|
|
#endif /* !_MINIX */
|
|
int terrno = ETIMEDOUT;
|
|
char junk[512];
|
|
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG) {
|
|
printf("res_send()\n");
|
|
__p_query(buf);
|
|
}
|
|
#endif /* DEBUG */
|
|
if (!(_res.options & RES_INIT))
|
|
if (res_init() == -1) {
|
|
return(-1);
|
|
}
|
|
|
|
v_circuit = (_res.options & RES_USEVC) || buflen > PACKETSZ;
|
|
#if !_MINIX
|
|
id = hp->id;
|
|
#else /* _MINIX */
|
|
id = hp->dh_id;
|
|
#endif /* !_MINIX */
|
|
/*
|
|
* Send request, RETRY times, or until successful
|
|
*/
|
|
for (try = 0; try < _res.retry; try++) {
|
|
for (ns = 0; ns < _res.nscount; ns++) {
|
|
#ifdef DEBUG
|
|
#if !_MINIX
|
|
if (_res.options & RES_DEBUG)
|
|
printf("Querying server (# %d) address = %s\n", ns+1,
|
|
inet_ntoa(_res.nsaddr_list[ns].sin_addr));
|
|
#else /* _MINIX */
|
|
if (_res.options & RES_DEBUG)
|
|
printf("Querying server (# %d) address = %s\n", ns+1,
|
|
inet_ntoa(_res.nsaddr_list[ns]));
|
|
#endif /* !_MINIX */
|
|
#endif /* DEBUG */
|
|
usevc:
|
|
if (v_circuit) {
|
|
#if !_MINIX
|
|
int truncated = 0;
|
|
|
|
/*
|
|
* Use virtual circuit;
|
|
* at most one attempt per server.
|
|
*/
|
|
try = _res.retry;
|
|
if (s < 0) {
|
|
s = socket(AF_INET, SOCK_STREAM, 0);
|
|
if (s < 0) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("socket (vc) failed");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
if (connect(s,
|
|
(struct sockaddr *)&(_res.nsaddr_list[ns]),
|
|
sizeof(struct sockaddr)) < 0) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("connect failed");
|
|
#endif /* DEBUG */
|
|
(void) close(s);
|
|
s = -1;
|
|
continue;
|
|
}
|
|
}
|
|
/*
|
|
* Send length & message
|
|
*/
|
|
len = htons((u_short)buflen);
|
|
iov[0].iov_base = (caddr_t)&len;
|
|
iov[0].iov_len = sizeof(len);
|
|
iov[1].iov_base = (char *)buf;
|
|
iov[1].iov_len = buflen;
|
|
if (writev(s, iov, 2) != sizeof(len) + buflen) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("write failed");
|
|
#endif /* DEBUG */
|
|
(void) close(s);
|
|
s = -1;
|
|
continue;
|
|
}
|
|
/*
|
|
* Receive length & response
|
|
*/
|
|
cp = answer;
|
|
len = sizeof(short);
|
|
while (len != 0 &&
|
|
(n = read(s, (char *)cp, (int)len)) > 0) {
|
|
cp += n;
|
|
len -= n;
|
|
}
|
|
if (n <= 0) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("read failed");
|
|
#endif /* DEBUG */
|
|
(void) close(s);
|
|
s = -1;
|
|
/*
|
|
* A long running process might get its TCP
|
|
* connection reset if the remote server was
|
|
* restarted. Requery the server instead of
|
|
* trying a new one. When there is only one
|
|
* server, this means that a query might work
|
|
* instead of failing. We only allow one reset
|
|
* per query to prevent looping.
|
|
*/
|
|
if (terrno == ECONNRESET && !connreset) {
|
|
connreset = 1;
|
|
ns--;
|
|
}
|
|
continue;
|
|
}
|
|
cp = answer;
|
|
if ((resplen = ntohs(*(u_short *)cp)) > anslen) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
fprintf(stderr, "response truncated\n");
|
|
#endif /* DEBUG */
|
|
len = anslen;
|
|
truncated = 1;
|
|
} else
|
|
len = resplen;
|
|
while (len != 0 &&
|
|
(n = read(s, (char *)cp, (int)len)) > 0) {
|
|
cp += n;
|
|
len -= n;
|
|
}
|
|
if (n <= 0) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("read failed");
|
|
#endif /* DEBUG */
|
|
(void) close(s);
|
|
s = -1;
|
|
continue;
|
|
}
|
|
if (truncated) {
|
|
/*
|
|
* Flush rest of answer
|
|
* so connection stays in synch.
|
|
*/
|
|
anhp->tc = 1;
|
|
len = resplen - anslen;
|
|
while (len != 0) {
|
|
n = (len > sizeof(junk) ?
|
|
sizeof(junk) : len);
|
|
if ((n = read(s, junk, n)) > 0)
|
|
len -= n;
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
#else /* _MINIX */
|
|
int truncated = 0;
|
|
int nbytes;
|
|
|
|
/*
|
|
* Use virtual circuit;
|
|
* at most one attempt per server.
|
|
*/
|
|
try = _res.retry;
|
|
if (s < 0)
|
|
{
|
|
s= tcp_connect(_res.nsaddr_list[ns],
|
|
_res.nsport_list[ns], &terrno);
|
|
if (s == -1)
|
|
continue;
|
|
}
|
|
/*
|
|
* Send length & message
|
|
*/
|
|
len = htons((u_short)buflen);
|
|
nbytes= tcpip_writeall(s, (char *)&len,
|
|
sizeof(len));
|
|
if (nbytes != sizeof(len))
|
|
{
|
|
terrno= errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
fprintf(stderr, "write failed: %s\n",
|
|
strerror(terrno));
|
|
#endif /* DEBUG */
|
|
close(s);
|
|
s= -1;
|
|
continue;
|
|
}
|
|
nbytes= tcpip_writeall(s, buf, buflen);
|
|
if (nbytes != buflen)
|
|
{
|
|
terrno= errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
fprintf(stderr, "write failed: %s\n",
|
|
strerror(terrno));
|
|
#endif /* DEBUG */
|
|
close(s);
|
|
s= -1;
|
|
continue;
|
|
}
|
|
/*
|
|
* Receive length & response
|
|
*/
|
|
cp = answer;
|
|
len = sizeof(short);
|
|
while (len != 0)
|
|
{
|
|
n = read(s, (char *)cp, (int)len);
|
|
if (n <= 0)
|
|
break;
|
|
cp += n;
|
|
assert(len >= n);
|
|
len -= n;
|
|
}
|
|
if (len) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
fprintf(stderr, "read failed: %s\n",
|
|
strerror(terrno));
|
|
#endif /* DEBUG */
|
|
close(s);
|
|
s= -1;
|
|
/*
|
|
* A long running process might get its TCP
|
|
* connection reset if the remote server was
|
|
* restarted. Requery the server instead of
|
|
* trying a new one. When there is only one
|
|
* server, this means that a query might work
|
|
* instead of failing. We only allow one reset
|
|
* per query to prevent looping.
|
|
*/
|
|
if (terrno == ECONNRESET && !connreset) {
|
|
connreset = 1;
|
|
ns--;
|
|
}
|
|
continue;
|
|
}
|
|
cp = answer;
|
|
if ((resplen = ntohs(*(u_short *)cp)) > anslen) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
fprintf(stderr, "response truncated\n");
|
|
#endif /* DEBUG */
|
|
len = anslen;
|
|
truncated = 1;
|
|
} else
|
|
len = resplen;
|
|
while (len != 0)
|
|
{
|
|
n= read(s, (char *)cp, (int)len);
|
|
if (n <= 0)
|
|
break;
|
|
cp += n;
|
|
assert(len >= n);
|
|
len -= n;
|
|
}
|
|
if (len) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
fprintf(stderr, "read failed: %s\n",
|
|
strerror(terrno));
|
|
#endif /* DEBUG */
|
|
close(s);
|
|
s= -1;
|
|
continue;
|
|
}
|
|
if (truncated) {
|
|
/*
|
|
* Flush rest of answer
|
|
* so connection stays in synch.
|
|
*/
|
|
anhp->dh_flag1 |= DHF_TC;
|
|
len = resplen - anslen;
|
|
while (len != 0) {
|
|
n = (len > sizeof(junk) ?
|
|
sizeof(junk) : len);
|
|
n = read(s, junk, n);
|
|
if (n <= 0)
|
|
{
|
|
assert(len >= n);
|
|
len -= n;
|
|
}
|
|
else
|
|
break;
|
|
}
|
|
}
|
|
#endif /* _MINIX */
|
|
} else {
|
|
#if !_MINIX
|
|
/*
|
|
* Use datagrams.
|
|
*/
|
|
if (s < 0) {
|
|
s = socket(AF_INET, SOCK_DGRAM, 0);
|
|
if (s < 0) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("socket (dg) failed");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
}
|
|
#if BSD >= 43
|
|
/*
|
|
* I'm tired of answering this question, so:
|
|
* On a 4.3BSD+ machine (client and server,
|
|
* actually), sending to a nameserver datagram
|
|
* port with no nameserver will cause an
|
|
* ICMP port unreachable message to be returned.
|
|
* If our datagram socket is "connected" to the
|
|
* server, we get an ECONNREFUSED error on the next
|
|
* socket operation, and select returns if the
|
|
* error message is received. We can thus detect
|
|
* the absence of a nameserver without timing out.
|
|
* If we have sent queries to at least two servers,
|
|
* however, we don't want to remain connected,
|
|
* as we wish to receive answers from the first
|
|
* server to respond.
|
|
*/
|
|
if (_res.nscount == 1 || (try == 0 && ns == 0)) {
|
|
/*
|
|
* Don't use connect if we might
|
|
* still receive a response
|
|
* from another server.
|
|
*/
|
|
if (connected == 0) {
|
|
if (connect(s, (struct sockaddr *)&_res.nsaddr_list[ns],
|
|
sizeof(struct sockaddr)) < 0) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("connect");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
connected = 1;
|
|
}
|
|
if (send(s, buf, buflen, 0) != buflen) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("send");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
} else {
|
|
/*
|
|
* Disconnect if we want to listen
|
|
* for responses from more than one server.
|
|
*/
|
|
if (connected) {
|
|
(void) connect(s, &no_addr,
|
|
sizeof(no_addr));
|
|
connected = 0;
|
|
}
|
|
#endif /* BSD */
|
|
if (sendto(s, buf, buflen, 0,
|
|
(struct sockaddr *)&_res.nsaddr_list[ns],
|
|
sizeof(struct sockaddr)) != buflen) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("sendto");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
#if BSD >= 43
|
|
}
|
|
#endif /* BSD */
|
|
|
|
/*
|
|
* Wait for reply
|
|
*/
|
|
timeout.tv_sec = (_res.retrans << try);
|
|
if (try > 0)
|
|
timeout.tv_sec /= _res.nscount;
|
|
if (timeout.tv_sec <= 0)
|
|
timeout.tv_sec = 1;
|
|
timeout.tv_usec = 0;
|
|
wait:
|
|
FD_ZERO(&dsmask);
|
|
FD_SET(s, &dsmask);
|
|
n = select(s+1, &dsmask, (fd_set *)NULL,
|
|
(fd_set *)NULL, &timeout);
|
|
if (n < 0) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("select");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
if (n == 0) {
|
|
/*
|
|
* timeout
|
|
*/
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf("timeout\n");
|
|
#endif /* DEBUG */
|
|
#if BSD >= 43
|
|
gotsomewhere = 1;
|
|
#endif
|
|
continue;
|
|
}
|
|
if ((resplen = recv(s, answer, anslen, 0)) <= 0) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("recvfrom");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
gotsomewhere = 1;
|
|
if (id != anhp->id) {
|
|
/*
|
|
* response from old query, ignore it
|
|
*/
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG) {
|
|
printf("old answer:\n");
|
|
__p_query(answer);
|
|
}
|
|
#endif /* DEBUG */
|
|
goto wait;
|
|
}
|
|
if (!(_res.options & RES_IGNTC) && anhp->tc) {
|
|
/*
|
|
* get rest of answer;
|
|
* use TCP with same server.
|
|
*/
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf("truncated answer\n");
|
|
#endif /* DEBUG */
|
|
(void) close(s);
|
|
s = -1;
|
|
v_circuit = 1;
|
|
goto usevc;
|
|
}
|
|
#else /* _MINIX */
|
|
/*
|
|
* Use datagrams.
|
|
*/
|
|
if (s < 0) {
|
|
s = udp_connect();
|
|
if (s < 0) {
|
|
terrno = errno;
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("udp_connect failed");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
}
|
|
if (udp_sendto(s, buf, buflen, _res.nsaddr_list[ns],
|
|
_res.nsport_list[ns]) != buflen) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("sendto");
|
|
#endif /* DEBUG */
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* Wait for reply
|
|
*/
|
|
timeout= (_res.retrans << try);
|
|
if (try > 0)
|
|
timeout /= _res.nscount;
|
|
if (timeout <= 0)
|
|
timeout= 1;
|
|
wait:
|
|
if ((resplen= udp_receive(s, answer, anslen, timeout))
|
|
== -1)
|
|
{
|
|
if (errno == EINTR)
|
|
{
|
|
/*
|
|
* timeout
|
|
*/
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf("timeout\n");
|
|
#endif /* DEBUG */
|
|
gotsomewhere = 1;
|
|
}
|
|
else
|
|
{
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
perror("udp_receive");
|
|
#endif /* DEBUG */
|
|
}
|
|
continue;
|
|
}
|
|
gotsomewhere = 1;
|
|
if (id != anhp->dh_id) {
|
|
/*
|
|
* response from old query, ignore it
|
|
*/
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG) {
|
|
printf("old answer:\n");
|
|
__p_query(answer);
|
|
}
|
|
#endif /* DEBUG */
|
|
goto wait;
|
|
}
|
|
if (!(_res.options & RES_IGNTC) &&
|
|
(anhp->dh_flag1 & DHF_TC)) {
|
|
/*
|
|
* get rest of answer;
|
|
* use TCP with same server.
|
|
*/
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf("truncated answer\n");
|
|
#endif /* DEBUG */
|
|
(void) close(s);
|
|
s = -1;
|
|
v_circuit = 1;
|
|
goto usevc;
|
|
}
|
|
#endif /* !_MINIX */
|
|
}
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG) {
|
|
printf("got answer:\n");
|
|
__p_query(answer);
|
|
}
|
|
#endif /* DEBUG */
|
|
/*
|
|
* If using virtual circuits, we assume that the first server
|
|
* is preferred * over the rest (i.e. it is on the local
|
|
* machine) and only keep that one open.
|
|
* If we have temporarily opened a virtual circuit,
|
|
* or if we haven't been asked to keep a socket open,
|
|
* close the socket.
|
|
*/
|
|
if ((v_circuit &&
|
|
((_res.options & RES_USEVC) == 0 || ns != 0)) ||
|
|
(_res.options & RES_STAYOPEN) == 0) {
|
|
(void) close(s);
|
|
s = -1;
|
|
}
|
|
return (resplen);
|
|
}
|
|
}
|
|
if (s >= 0) {
|
|
(void) close(s);
|
|
s = -1;
|
|
}
|
|
if (v_circuit == 0)
|
|
if (gotsomewhere == 0)
|
|
errno = ECONNREFUSED; /* no nameservers found */
|
|
else
|
|
errno = ETIMEDOUT; /* no answer obtained */
|
|
else
|
|
errno = terrno;
|
|
return (-1);
|
|
}
|
|
|
|
/*
|
|
* This routine is for closing the socket if a virtual circuit is used and
|
|
* the program wants to close it. This provides support for endhostent()
|
|
* which expects to close the socket.
|
|
*
|
|
* This routine is not expected to be user visible.
|
|
*/
|
|
void
|
|
_res_close()
|
|
{
|
|
if (s != -1) {
|
|
(void) close(s);
|
|
s = -1;
|
|
}
|
|
}
|
|
|
|
#if _MINIX
|
|
static int tcp_connect(host, port, terrno)
|
|
ipaddr_t host;
|
|
tcpport_t port;
|
|
int *terrno;
|
|
{
|
|
char *dev_name;
|
|
int fd;
|
|
int error;
|
|
nwio_tcpconf_t tcpconf;
|
|
nwio_tcpcl_t clopt;
|
|
|
|
dev_name= getenv("TCP_DEVICE");
|
|
if (!dev_name)
|
|
dev_name= TCP_DEVICE;
|
|
fd= open(dev_name, O_RDWR);
|
|
if (fd == -1)
|
|
{
|
|
*terrno= errno;
|
|
return -1;
|
|
}
|
|
tcpconf.nwtc_flags= NWTC_EXCL | NWTC_LP_SEL | NWTC_SET_RA | NWTC_SET_RP;
|
|
tcpconf.nwtc_remaddr= host;
|
|
tcpconf.nwtc_remport= port;
|
|
error= ioctl(fd, NWIOSTCPCONF, &tcpconf);
|
|
if (error == -1)
|
|
{
|
|
*terrno= errno;
|
|
close(fd);
|
|
return -1;
|
|
}
|
|
clopt.nwtcl_flags= 0;
|
|
error= ioctl(fd, NWIOTCPCONN, &clopt);
|
|
if (error == -1)
|
|
{
|
|
*terrno= errno;
|
|
close(fd);
|
|
return -1;
|
|
}
|
|
*terrno= 0;
|
|
return fd;
|
|
}
|
|
|
|
static int tcpip_writeall(fd, buf, siz)
|
|
int fd;
|
|
const char *buf;
|
|
size_t siz;
|
|
{
|
|
size_t siz_org;
|
|
int nbytes;
|
|
|
|
siz_org= siz;
|
|
|
|
while (siz)
|
|
{
|
|
nbytes= write(fd, buf, siz);
|
|
if (nbytes <= 0)
|
|
return siz_org-siz;
|
|
assert(siz >= nbytes);
|
|
buf += nbytes;
|
|
siz -= nbytes;
|
|
}
|
|
return siz_org;
|
|
}
|
|
|
|
|
|
static int udp_connect()
|
|
{
|
|
nwio_udpopt_t udpopt;
|
|
char *dev_name;
|
|
int fd, r, terrno;
|
|
|
|
dev_name= getenv("UDP_DEVICE");
|
|
if (!dev_name)
|
|
dev_name= UDP_DEVICE;
|
|
fd= open(dev_name, O_RDWR);
|
|
if (fd == -1)
|
|
return -1;
|
|
|
|
udpopt.nwuo_flags= NWUO_COPY | NWUO_LP_SEL | NWUO_EN_LOC |
|
|
NWUO_EN_BROAD | NWUO_RP_ANY | NWUO_RA_ANY | NWUO_RWDATALL |
|
|
NWUO_DI_IPOPT;
|
|
r= ioctl(fd, NWIOSUDPOPT, &udpopt);
|
|
if (r == -1)
|
|
{
|
|
terrno= errno;
|
|
close(fd);
|
|
errno= terrno;
|
|
return -1;
|
|
}
|
|
return fd;
|
|
}
|
|
|
|
static int udp_sendto(fd, buf, buflen, addr, port)
|
|
int fd;
|
|
const char *buf;
|
|
unsigned buflen;
|
|
ipaddr_t addr;
|
|
udpport_t port;
|
|
{
|
|
char *newbuf;
|
|
udp_io_hdr_t *udp_io_hdr;
|
|
int r, terrno;
|
|
|
|
newbuf= malloc(sizeof(*udp_io_hdr) + buflen);
|
|
if (newbuf == NULL)
|
|
{
|
|
errno= ENOMEM;
|
|
return -1;
|
|
}
|
|
udp_io_hdr= (udp_io_hdr_t *)newbuf;
|
|
udp_io_hdr->uih_dst_addr= addr;
|
|
udp_io_hdr->uih_dst_port= port;
|
|
udp_io_hdr->uih_ip_opt_len= 0;
|
|
udp_io_hdr->uih_data_len= buflen;
|
|
|
|
memcpy(newbuf + sizeof(*udp_io_hdr), buf, buflen);
|
|
r= write(fd, newbuf, sizeof(*udp_io_hdr) + buflen);
|
|
terrno= errno;
|
|
free(newbuf);
|
|
if (r >= sizeof(*udp_io_hdr))
|
|
r -= sizeof(*udp_io_hdr);
|
|
errno= terrno;
|
|
return r;
|
|
}
|
|
|
|
static int udp_receive(fd, buf, buflen, timeout)
|
|
int fd;
|
|
char *buf;
|
|
unsigned buflen;
|
|
time_t timeout;
|
|
{
|
|
char *newbuf;
|
|
udp_io_hdr_t *udp_io_hdr;
|
|
int r, terrno;
|
|
fd_set readfds;
|
|
struct timeval timeval;
|
|
|
|
/* allocate buffer for packet */
|
|
newbuf = malloc(sizeof(*udp_io_hdr) + buflen);
|
|
if (newbuf == NULL)
|
|
{
|
|
errno = ENOMEM;
|
|
return -1;
|
|
}
|
|
|
|
/* only read if there is something to be read within timeout seconds */
|
|
FD_ZERO(&readfds);
|
|
FD_SET(fd, &readfds);
|
|
timeval.tv_sec = timeout;
|
|
timeval.tv_usec = 0;
|
|
r = select(fd + 1, &readfds, NULL, NULL, &timeval);
|
|
if (r >= 0 && !FD_ISSET(fd, &readfds))
|
|
{
|
|
errno = EINTR;
|
|
r = -1;
|
|
}
|
|
|
|
if (r >= 0)
|
|
r = read(fd, newbuf, sizeof(*udp_io_hdr) + buflen);
|
|
|
|
/* clean up in case of failure */
|
|
terrno = errno;
|
|
if (r < 0 || r <= sizeof(*udp_io_hdr))
|
|
{
|
|
if (r > 0)
|
|
r = 0;
|
|
|
|
free(newbuf);
|
|
errno = terrno;
|
|
return r;
|
|
}
|
|
|
|
/* copy packet body to caller-provided buffer */
|
|
memcpy(buf, newbuf + sizeof(*udp_io_hdr), r - sizeof(*udp_io_hdr));
|
|
free(newbuf);
|
|
|
|
return r - sizeof(*udp_io_hdr);
|
|
}
|
|
|
|
#endif
|