/*-
* Copyright (c) 2006 Robert N. M. Watson
* Copyright (c) 2011 Juniper Networks, Inc.
* All rights reserved.
*
* Portions of this software were developed by Robert N. M. Watson under
* contract to Juniper Networks, Inc.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
/*
* TCP regression test that opens a loopback TCP session, then closes one end
* while shutting down the other. This triggers an unusual TCP stack case in
* which an open file descriptor / socket is associated with a closed TCP
* connection.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <err.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static void
tcp_server(pid_t partner, int listen_fd)
{
int error, accept_fd;
accept_fd = accept(listen_fd, NULL, NULL);
if (accept_fd < 0) {
error = errno;
(void)kill(partner, SIGTERM);
errno = error;
err(-1, "tcp_server: accept");
}
close(accept_fd);
close(listen_fd);
}
static void
tcp_client(pid_t partner, u_short port, int secs)
{
struct sockaddr_in sin;
int error, sock;
sleep(1);
sock = socket(PF_INET, SOCK_STREAM, 0);
if (sock < 0) {
error = errno;
(void)kill(partner, SIGTERM);
errno = error;
err(-1, "socket");
}
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_len = sizeof(sin);
sin.sin_addr.s_addr = ntohl(INADDR_LOOPBACK);
sin.sin_port = port;
if (connect(sock, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
error = errno;
(void)kill(partner, SIGTERM);
errno = error;
err(-1, "connect");
}
if (shutdown(sock, SHUT_RDWR) < 0) {
error = errno;
(void)kill(partner, SIGTERM);
errno = error;
err(-1, "shutdown");
}
sleep(secs);
close(sock);
}
int
main(int argc, char *argv[])
{
struct sockaddr_in sin;
pid_t child_pid, parent_pid;
int listen_fd;
socklen_t len;
u_short port;
if (signal(SIGCHLD, SIG_IGN) == SIG_ERR)
err(-1, "signal");
/*
* Run the whole thing twice: once, with a short sleep in the client,
* so that we close before time wait runs out, and once with a long
* sleep so that the time wait terminates while the socket is open.
* We don't reuse listen sockets between runs.
*/
listen_fd = socket(PF_INET, SOCK_STREAM, 0);
if (listen_fd < 0)
err(-1, "socket");
/*
* We use the loopback, but let the kernel select a port for the
* server socket.
*/
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_len = sizeof(sin);
sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
if (bind(listen_fd, (struct sockaddr *)&sin, sizeof(sin)) < 0)
err(-1, "bind");
if (listen(listen_fd, -1) < 0)
err(-1, "listen");
/*
* Query the port so that the client can use it.
*/
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_len = sizeof(sin);
len = sizeof(sin);
if (getsockname(listen_fd, (struct sockaddr *)&sin, &len) < 0)
err(-1, "getsockname");
port = sin.sin_port;
printf("Using port %d\n", ntohs(port));
parent_pid = getpid();
child_pid = fork();
if (child_pid < 0)
err(-1, "fork");
if (child_pid == 0) {
child_pid = getpid();
tcp_server(child_pid, listen_fd);
exit(0);
} else
tcp_client(parent_pid, port, 1);
(void)kill(child_pid, SIGTERM);
close(listen_fd);
sleep(5);
/*
* Start again, this time long sleep.
*/
listen_fd = socket(PF_INET, SOCK_STREAM, 0);
if (listen_fd < 0)
err(-1, "socket");
/*
* We use the loopback, but let the kernel select a port for the
* server socket.
*/
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_len = sizeof(sin);
sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
if (bind(listen_fd, (struct sockaddr *)&sin, sizeof(sin)) < 0)
err(-1, "bind");
if (listen(listen_fd, -1) < 0)
err(-1, "listen");
/*
* Query the port so that the client can use it.
*/
bzero(&sin, sizeof(sin));
sin.sin_family = AF_INET;
sin.sin_len = sizeof(sin);
len = sizeof(sin);
if (getsockname(listen_fd, (struct sockaddr *)&sin, &len) < 0)
err(-1, "getsockname");
port = sin.sin_port;
printf("Using port %d\n", ntohs(port));
parent_pid = getpid();
child_pid = fork();
if (child_pid < 0)
err(-1, "fork");
if (child_pid == 0) {
child_pid = getpid();
tcp_server(parent_pid, listen_fd);
} else
tcp_client(child_pid, port, 800);
return (0);
}
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