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: stable/9/tools/regression/netinet/tcpdrop/tcpdrop.c 224688 2011-08-06 19:20:17Z rwatson $
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
53 static int
tcp_drop(struct sockaddr_in * sin_local,struct sockaddr_in * sin_remote)54 tcp_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
70 static void
tcp_server(pid_t partner,int listen_fd)71 tcp_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
121 static void
tcp_client(pid_t partner,u_short port)122 tcp_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
202 int
main(int argc,char * argv[])203 main(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