1 /*-
2 * Copyright (c) 1999 The NetBSD Foundation, Inc.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to The NetBSD Foundation
6 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
7 * NASA Ames Research Center.
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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
19 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
20 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
22 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 *
30 * Obtained from: $NetBSD: shmtest.c,v 1.3 2002/07/20 08:36:26 grant Exp $
31 */
32
33 /*
34 * Test the SVID-compatible Shared Memory facility.
35 */
36
37 #include <sys/types.h>
38 #include <sys/ipc.h>
39 #include <sys/shm.h>
40 #include <sys/wait.h>
41
42 #include <err.h>
43 #include <errno.h>
44 #include <signal.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <time.h>
49 #include <unistd.h>
50
51 static void print_shmid_ds(struct shmid_ds *, mode_t);
52 static void sigsys_handler(int);
53 static void sigchld_handler(int);
54 static void cleanup(void);
55 static void receiver(void);
56 static void usage(void) __dead2;
57
58 static const char *m_str = "The quick brown fox jumped over the lazy dog.";
59
60 static int sender_shmid = -1;
61 static pid_t child_pid;
62 static key_t shmkey;
63 static size_t pgsize;
64
65 int
main(int argc,char * argv[])66 main(int argc, char *argv[])
67 {
68 struct sigaction sa;
69 struct shmid_ds s_ds;
70 sigset_t sigmask;
71 char *shm_buf;
72
73 if (argc != 2)
74 usage();
75
76 /*
77 * Install a SIGSYS handler so that we can exit gracefully if
78 * System V Shared Memory support isn't in the kernel.
79 */
80 sa.sa_handler = sigsys_handler;
81 sigemptyset(&sa.sa_mask);
82 sa.sa_flags = 0;
83 if (sigaction(SIGSYS, &sa, NULL) == -1)
84 err(1, "sigaction SIGSYS");
85
86 /*
87 * Install and SIGCHLD handler to deal with all possible exit
88 * conditions of the receiver.
89 */
90 sa.sa_handler = sigchld_handler;
91 sigemptyset(&sa.sa_mask);
92 sa.sa_flags = 0;
93 if (sigaction(SIGCHLD, &sa, NULL) == -1)
94 err(1, "sigaction SIGCHLD");
95
96 pgsize = sysconf(_SC_PAGESIZE);
97
98 shmkey = ftok(argv[1], 4160);
99
100 /*
101 * Initialize child_pid to ourselves to that the cleanup function
102 * works before we create the receiver.
103 */
104 child_pid = getpid();
105
106 /*
107 * Make sure that when the sender exits, the message queue is
108 * removed.
109 */
110 if (atexit(cleanup) == -1)
111 err(1, "atexit");
112
113 if ((sender_shmid = shmget(shmkey, pgsize, IPC_CREAT | 0640)) == -1)
114 err(1, "shmget");
115
116 if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1)
117 err(1, "shmctl IPC_STAT");
118
119 print_shmid_ds(&s_ds, 0640);
120
121 s_ds.shm_perm.mode = (s_ds.shm_perm.mode & ~0777) | 0600;
122
123 if (shmctl(sender_shmid, IPC_SET, &s_ds) == -1)
124 err(1, "shmctl IPC_SET");
125
126 memset(&s_ds, 0, sizeof(s_ds));
127
128 if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1)
129 err(1, "shmctl IPC_STAT");
130
131 if ((s_ds.shm_perm.mode & 0777) != 0600)
132 err(1, "IPC_SET of mode didn't hold");
133
134 print_shmid_ds(&s_ds, 0600);
135
136 if ((shm_buf = shmat(sender_shmid, NULL, 0)) == (void *) -1)
137 err(1, "sender: shmat");
138
139 /*
140 * Write the test pattern into the shared memory buffer.
141 */
142 strcpy(shm_buf, m_str);
143
144 switch ((child_pid = fork())) {
145 case -1:
146 err(1, "fork");
147 /* NOTREACHED */
148
149 case 0:
150 receiver();
151 break;
152
153 default:
154 break;
155 }
156
157 /*
158 * Suspend forever; when we get SIGCHLD, the handler will exit.
159 */
160 sigemptyset(&sigmask);
161 (void) sigsuspend(&sigmask);
162
163 /*
164 * ...and any other signal is an unexpected error.
165 */
166 errx(1, "sender: received unexpected signal");
167 }
168
169 static void
sigsys_handler(int signo __unused)170 sigsys_handler(int signo __unused)
171 {
172
173 errx(1, "System V Shared Memory support is not present in the kernel");
174 }
175
176 static void
sigchld_handler(int signo __unused)177 sigchld_handler(int signo __unused)
178 {
179 struct shmid_ds s_ds;
180 int cstatus;
181
182 /*
183 * Reap the child; if it exited successfully, then the test passed!
184 */
185 if (waitpid(child_pid, &cstatus, 0) != child_pid)
186 err(1, "waitpid");
187
188 if (WIFEXITED(cstatus) == 0)
189 errx(1, "receiver exited abnormally");
190
191 if (WEXITSTATUS(cstatus) != 0)
192 errx(1, "receiver exited with status %d",
193 WEXITSTATUS(cstatus));
194
195 /*
196 * If we get here, the child has exited normally, and thus
197 * we should exit normally too. First, tho, we print out
198 * the final stats for the message queue.
199 */
200
201 if (shmctl(sender_shmid, IPC_STAT, &s_ds) == -1)
202 err(1, "shmctl IPC_STAT");
203
204 print_shmid_ds(&s_ds, 0600);
205
206 exit(0);
207 }
208
209 static void
cleanup(void)210 cleanup(void)
211 {
212
213 /*
214 * If we're the sender, and it exists, remove the shared memory area.
215 */
216 if (child_pid != 0 && sender_shmid != -1) {
217 if (shmctl(sender_shmid, IPC_RMID, NULL) == -1)
218 warn("shmctl IPC_RMID");
219 }
220 }
221
222 static void
print_shmid_ds(struct shmid_ds * sp,mode_t mode)223 print_shmid_ds(struct shmid_ds *sp, mode_t mode)
224 {
225 uid_t uid = geteuid();
226 gid_t gid = getegid();
227
228 printf("PERM: uid %d, gid %d, cuid %d, cgid %d, mode 0%o\n",
229 sp->shm_perm.uid, sp->shm_perm.gid,
230 sp->shm_perm.cuid, sp->shm_perm.cgid,
231 sp->shm_perm.mode & 0777);
232
233 printf("segsz %lu, lpid %d, cpid %d, nattch %u\n",
234 (u_long)sp->shm_segsz, sp->shm_lpid, sp->shm_cpid,
235 sp->shm_nattch);
236
237 printf("atime: %s", ctime(&sp->shm_atime));
238 printf("dtime: %s", ctime(&sp->shm_dtime));
239 printf("ctime: %s", ctime(&sp->shm_ctime));
240
241 /*
242 * Sanity check a few things.
243 */
244
245 if (sp->shm_perm.uid != uid || sp->shm_perm.cuid != uid)
246 errx(1, "uid mismatch");
247
248 if (sp->shm_perm.gid != gid || sp->shm_perm.cgid != gid)
249 errx(1, "gid mismatch");
250
251 if ((sp->shm_perm.mode & 0777) != mode)
252 errx(1, "mode mismatch");
253 }
254
255 static void
usage(void)256 usage(void)
257 {
258
259 fprintf(stderr, "usage: %s keypath\n", getprogname());
260 exit(1);
261 }
262
263 static void
receiver(void)264 receiver(void)
265 {
266 int shmid;
267 void *shm_buf;
268
269 if ((shmid = shmget(shmkey, pgsize, 0)) == -1)
270 err(1, "receiver: shmget");
271
272 if ((shm_buf = shmat(shmid, NULL, 0)) == (void *) -1)
273 err(1, "receiver: shmat");
274
275 printf("%s\n", (const char *)shm_buf);
276 if (strcmp((const char *)shm_buf, m_str) != 0)
277 err(1, "receiver: data isn't correct");
278
279 exit(0);
280 }
281