xref: /freebsd/tests/sys/kern/unix_dgram.c (revision 5e801ac66d24704442eba426ed13c3effb8a34e7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2022 Gleb Smirnoff <glebius@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/time.h>
29 #include <sys/socket.h>
30 #include <sys/sysctl.h>
31 #include <sys/un.h>
32 #include <errno.h>
33 #include <fcntl.h>
34 #include <signal.h>
35 #include <stdlib.h>
36 
37 #include <atf-c.h>
38 
39 static struct itimerval itv = {
40 	.it_interval = { 0, 0 },
41 	.it_value = { 1, 0 },	/* one second */
42 };
43 static sig_atomic_t timer_done = 0;
44 static void
45 sigalarm(int sig __unused)
46 {
47 
48 	timer_done = 1;
49 }
50 
51 static struct sigaction sigact = {
52 	.sa_handler = sigalarm,
53 };
54 
55 /*
56  * Fill socket to a state when next send(len) would fail.
57  */
58 static void
59 fill(int fd, void *buf, ssize_t len)
60 {
61 	unsigned long recvspace;
62 	size_t llen = sizeof(unsigned long);
63 	ssize_t sent;
64 
65 	ATF_REQUIRE(sysctlbyname("net.local.dgram.recvspace", &recvspace,
66 	    &llen, NULL, 0) == 0);
67 	for (sent = 0; sent + len < (ssize_t)recvspace; sent += len)
68 		ATF_REQUIRE(send(fd, buf, len, 0) == len);
69 }
70 
71 ATF_TC_WITHOUT_HEAD(basic);
72 ATF_TC_BODY(basic, tc)
73 {
74 	struct msghdr msg;
75 	struct iovec iov[1];
76 	unsigned long maxdgram;
77 	size_t llen = sizeof(unsigned long);
78 	int fd[2];
79 	char *buf;
80 
81 	/* Allocate and initialize:
82 	 * - fd[0] to send, fd[1] to receive
83 	 * - buf[maxdgram] for data
84 	 */
85 	ATF_REQUIRE(sysctlbyname("net.local.dgram.maxdgram", &maxdgram,
86 	    &llen, NULL, 0) == 0);
87 	ATF_REQUIRE(socketpair(PF_UNIX, SOCK_DGRAM, 0, fd) != -1);
88 	buf = malloc(maxdgram + 1);
89 	ATF_REQUIRE(buf);
90 	msg = (struct msghdr ){
91 		.msg_iov = iov,
92 		.msg_iovlen = 1,
93 	};
94 	iov[0] = (struct iovec ){
95 		.iov_base = buf,
96 	};
97 
98 	/* Fail to send > maxdgram. */
99 	ATF_REQUIRE(send(fd[0], buf, maxdgram + 1, 0) == -1);
100 	ATF_REQUIRE(errno == EMSGSIZE);
101 
102 	/* Send maxdgram. */
103 	ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == (ssize_t)maxdgram);
104 
105 	/* Exercise MSG_PEEK, full and truncated.. */
106 	ATF_REQUIRE(recv(fd[1], buf, maxdgram, MSG_PEEK) == (ssize_t)maxdgram);
107 	iov[0].iov_len = 42;
108 	ATF_REQUIRE(recvmsg(fd[1], &msg, MSG_PEEK) == 42);
109 	ATF_REQUIRE(msg.msg_flags == (MSG_PEEK | MSG_TRUNC));
110 
111 	/* Receive maxdgram. */
112 	iov[0].iov_len = maxdgram;
113 	ATF_REQUIRE(recvmsg(fd[1], &msg, 0) == (ssize_t)maxdgram);
114 	ATF_REQUIRE(msg.msg_flags == 0);
115 
116 	/* Receive truncated message. */
117 	ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == (ssize_t)maxdgram);
118 	iov[0].iov_len = maxdgram / 2;
119 	ATF_REQUIRE(recvmsg(fd[1], &msg, 0) == (ssize_t)maxdgram / 2);
120 	ATF_REQUIRE(msg.msg_flags == MSG_TRUNC);
121 
122 	/* Empty: block. */
123 	ATF_REQUIRE(sigaction(SIGALRM, &sigact, NULL) == 0);
124 	ATF_REQUIRE(timer_done == 0);
125 	ATF_REQUIRE(setitimer(ITIMER_REAL, &itv, NULL) == 0);
126 	ATF_REQUIRE(recv(fd[1], buf, maxdgram, 0) == -1);
127 	ATF_REQUIRE(errno == EINTR);
128 	ATF_REQUIRE(timer_done == 1);
129 
130 	/* Don't block with MSG_DONTWAIT. */
131 	ATF_REQUIRE(recv(fd[1], buf, maxdgram, MSG_DONTWAIT) == -1);
132 	ATF_REQUIRE(errno == EAGAIN);
133 
134 	/* Don't block with O_NONBLOCK. */
135 	ATF_REQUIRE(fcntl(fd[1], F_SETFL, O_NONBLOCK) != -1);
136 	ATF_REQUIRE(recv(fd[1], buf, maxdgram, 0) == -1);
137 	ATF_REQUIRE(errno == EAGAIN);
138 
139 	/* Fail with ENOBUFS on full socket. */
140 	fill(fd[0], buf, maxdgram);
141 	ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == -1);
142 	ATF_REQUIRE(errno == ENOBUFS);
143 
144 	/* Fail with EAGAIN with O_NONBLOCK set. */
145 	ATF_REQUIRE(fcntl(fd[0], F_SETFL, O_NONBLOCK) != -1);
146 	ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == -1);
147 	ATF_REQUIRE(errno == EAGAIN);
148 
149 	/* Remote side closed -> ECONNRESET. */
150 	close(fd[1]);
151 	ATF_REQUIRE(send(fd[0], buf, maxdgram, 0) == -1);
152 	ATF_REQUIRE(errno == ECONNRESET);
153 }
154 
155 ATF_TC_WITHOUT_HEAD(one2many);
156 ATF_TC_BODY(one2many, tc)
157 {
158 	struct sockaddr_un sun;
159 	const char *path = "unix_dgram_listener";
160 	int one, many[2], two;
161 	char buf[1024];
162 
163 	/* Establish one to many connection. */
164 	ATF_REQUIRE((one = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0);
165 	bzero(&sun, sizeof(sun));
166 	sun.sun_family = AF_LOCAL;
167 	sun.sun_len = sizeof(sun);
168 	strlcpy(sun.sun_path, path, sizeof(sun.sun_path));
169 	ATF_REQUIRE(bind(one, (struct sockaddr *)&sun, sizeof(sun)) == 0);
170 	/* listen(2) shall fail. */
171 	ATF_REQUIRE(listen(one, -1) != 0);
172 	for (int i = 0; i < 2; i++) {
173 		ATF_REQUIRE((many[i] = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0);
174 		ATF_REQUIRE(connect(many[i], (struct sockaddr *)&sun,
175 		    sizeof(sun)) == 0);
176 	}
177 
178 	/* accept() on UNIX/DGRAM is invalid. */
179 	ATF_REQUIRE(accept(one, NULL, NULL) == -1);
180 	ATF_REQUIRE(errno == EINVAL);
181 
182 	/*
183 	 * Connecting a bound socket to self: a strange, useless, but
184 	 * historically existing edge case that is not explicitly described
185 	 * in SuS, neither is forbidden there. Works on FreeBSD and Linux.
186 	 */
187 	ATF_REQUIRE(connect(one, (struct sockaddr *)&sun, sizeof(sun)) == 0);
188 	ATF_REQUIRE(send(one, buf, 42, 0) == 42);
189 	ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == 42);
190 
191 	/*
192 	 * Sending from an unconnected socket to a bound socket.  Connection is
193 	 * created for the duration of the syscall.
194 	 */
195 	ATF_REQUIRE((two = socket(PF_UNIX, SOCK_DGRAM, 0)) > 0);
196 	ATF_REQUIRE(sendto(two, buf, 43, 0, (struct sockaddr *)&sun,
197 	    sizeof(sun)) == 43);
198 	ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == 43);
199 
200 	/* One sender can fill the receive side.
201 	 * Current behavior which needs improvement.
202 	 */
203 	fill(many[0], buf, sizeof(buf));
204 	ATF_REQUIRE(send(many[1], buf, sizeof(buf), 0) == -1);
205 	ATF_REQUIRE(errno == ENOBUFS);
206 	ATF_REQUIRE(recv(one, buf, sizeof(buf), 0) == sizeof(buf));
207 	ATF_REQUIRE(send(many[1], buf, sizeof(buf), 0) == sizeof(buf));
208 }
209 
210 ATF_TP_ADD_TCS(tp)
211 {
212 
213 	ATF_TP_ADD_TC(tp, basic);
214 	ATF_TP_ADD_TC(tp, one2many);
215 
216 	return (atf_no_error());
217 }
218