1/*-
2 * Copyright (c) 2006 Robert N. M. Watson
3 * Copyright (c) 2011 Juniper Networks, Inc.
4 * All rights reserved.
5 *
6 * Portions of this software were developed by Robert N. M. Watson under
7 * contract to Juniper Networks, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD$
31 */
32
33/*
34 * TCP regression test for the tcpdrop sysctl; build a loopback TCP
35 * connection, drop it, and make sure both endpoints return that the
36 * connection has been reset.
37 */
38
39#include <sys/types.h>
40#include <sys/socket.h>
41#include <sys/sysctl.h>
42
43#include <netinet/in.h>
44
45#include <err.h>
46#include <errno.h>
47#include <signal.h>
48#include <stdio.h>
49#include <stdlib.h>
50#include <string.h>
51#include <unistd.h>
52
53static int
54tcp_drop(struct sockaddr_in *sin_local, struct sockaddr_in *sin_remote)
55{
56	struct sockaddr_storage addrs[2];
57
58	/*
59	 * Sysctl accepts an array of two sockaddr's, the first being the
60	 * 'foreign' sockaddr, the second being the 'local' sockaddr.
61	 */
62
63	bcopy(sin_remote, &addrs[0], sizeof(*sin_remote));
64	bcopy(sin_local, &addrs[1], sizeof(*sin_local));
65
66	return (sysctlbyname("net.inet.tcp.drop", NULL, 0, addrs,
67	    sizeof(addrs)));
68}
69
70static void
71tcp_server(pid_t partner, int listen_fd)
72{
73	int error, accept_fd;
74	ssize_t len;
75	char ch;
76
77	accept_fd = accept(listen_fd, NULL, NULL);
78	if (accept_fd < 0) {
79		error = errno;
80		(void)kill(partner, SIGTERM);
81		errno = error;
82		err(-1, "tcp_server: accept");
83	}
84
85	/*
86	 * Send one byte, make sure that worked, wait for the drop, and try
87	 * sending another.  By sending small amounts, we avoid blocking
88	 * waiting on the remote buffer to be drained.
89	 */
90	ch = 'A';
91	len = send(accept_fd, &ch, sizeof(ch), MSG_NOSIGNAL);
92	if (len < 0) {
93		error = errno;
94		(void)kill(partner, SIGTERM);
95		errno = error;
96		err(-1, "tcp_server: send (1)");
97	}
98	if (len != sizeof(ch)) {
99		(void)kill(partner, SIGTERM);
100		errx(-1, "tcp_server: send (1) len");
101	}
102
103	sleep (10);
104
105	ch = 'A';
106	len = send(accept_fd, &ch, sizeof(ch), MSG_NOSIGNAL);
107	if (len >= 0) {
108		(void)kill(partner, SIGTERM);
109		errx(-1, "tcp_server: send (2): success");
110	} else if (errno != EPIPE) {
111		error = errno;
112		(void)kill(partner, SIGTERM);
113		errno = error;
114		err(-1, "tcp_server: send (2)");
115	}
116
117	close(accept_fd);
118	close(listen_fd);
119}
120
121static void
122tcp_client(pid_t partner, u_short port)
123{
124	struct sockaddr_in sin, sin_local;
125	int error, sock;
126	socklen_t slen;
127	ssize_t len;
128	char ch;
129
130	sleep(1);
131
132	sock = socket(PF_INET, SOCK_STREAM, 0);
133	if (sock < 0) {
134		error = errno;
135		(void)kill(partner, SIGTERM);
136		errno = error;
137		err(-1, "socket");
138	}
139
140	bzero(&sin, sizeof(sin));
141	sin.sin_family = AF_INET;
142	sin.sin_len = sizeof(sin);
143	sin.sin_addr.s_addr = ntohl(INADDR_LOOPBACK);
144	sin.sin_port = port;
145
146	if (connect(sock, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
147		error = errno;
148		(void)kill(partner, SIGTERM);
149		errno = error;
150		err(-1, "connect");
151	}
152
153	slen = sizeof(sin_local);
154	if (getsockname(sock, (struct sockaddr *)&sin_local, &slen) < 0) {
155		error = errno;
156		(void)kill(partner, SIGTERM);
157		errno = error;
158		err(-1, "getsockname");
159	}
160
161	/*
162	 * Send one byte, make sure that worked, wait for the drop, and try
163	 * sending another.  By sending small amounts, we avoid blocking
164	 * waiting on the remote buffer to be drained.
165	 */
166	ch = 'A';
167	len = send(sock, &ch, sizeof(ch), MSG_NOSIGNAL);
168	if (len < 0) {
169		error = errno;
170		(void)kill(partner, SIGTERM);
171		errno = error;
172		err(-1, "tcp_client: send (1)");
173	}
174	if (len != sizeof(ch)) {
175		(void)kill(partner, SIGTERM);
176		errx(-1, "tcp_client: send (1) len");
177	}
178
179	sleep(5);
180	if (tcp_drop(&sin_local, &sin) < 0) {
181		error = errno;
182		(void)kill(partner, SIGTERM);
183		errno = error;
184		err(-1, "tcp_client: tcp_drop");
185	}
186	sleep(5);
187
188	ch = 'A';
189	len = send(sock, &ch, sizeof(ch), MSG_NOSIGNAL);
190	if (len >= 0) {
191		(void)kill(partner, SIGTERM);
192		errx(-1, "tcp_client: send (2): success");
193	} else if (errno != EPIPE) {
194		error = errno;
195		(void)kill(partner, SIGTERM);
196		errno = error;
197		err(-1, "tcp_client: send (2)");
198	}
199	close(sock);
200}
201
202int
203main(int argc, char *argv[])
204{
205	pid_t child_pid, parent_pid;
206	struct sockaddr_in sin;
207	int listen_fd;
208	u_short port;
209	socklen_t len;
210
211	listen_fd = socket(PF_INET, SOCK_STREAM, 0);
212	if (listen_fd < 0)
213		err(-1, "socket");
214
215	/*
216	 * We use the loopback, but let the kernel select a port for the
217	 * server socket.
218	 */
219	bzero(&sin, sizeof(sin));
220	sin.sin_family = AF_INET;
221	sin.sin_len = sizeof(sin);
222	sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
223
224	if (bind(listen_fd, (struct sockaddr *)&sin, sizeof(sin)) < 0)
225		err(-1, "bind");
226
227	if (listen(listen_fd, -1) < 0)
228		err(-1, "listen");
229
230	/*
231	 * Query the port so that the client can use it.
232	 */
233	bzero(&sin, sizeof(sin));
234	sin.sin_family = AF_INET;
235	sin.sin_len = sizeof(sin);
236	len = sizeof(sin);
237	if (getsockname(listen_fd, (struct sockaddr *)&sin, &len) < 0)
238		err(-1, "getsockname");
239	port = sin.sin_port;
240	printf("Using port %d\n", ntohs(port));
241
242	if (signal(SIGCHLD, SIG_IGN) == SIG_ERR)
243		err(-1, "signal");
244
245	parent_pid = getpid();
246	child_pid = fork();
247	if (child_pid < 0)
248		err(-1, "fork");
249	if (child_pid == 0) {
250		child_pid = getpid();
251		tcp_server(parent_pid, listen_fd);
252	} else
253		tcp_client(child_pid, port);
254
255	return (0);
256}
257