xref: /openbsd-src/regress/lib/libc/sys/t_kill.c (revision c02cd12511bd98f410ea5913f5c4488a8730ee33)
1 /*	$OpenBSD: t_kill.c,v 1.2 2021/07/29 15:33:17 anton Exp $	*/
2 /* $NetBSD: t_kill.c,v 1.1 2011/07/07 06:57:53 jruoho Exp $ */
3 
4 /*-
5  * Copyright (c) 2011 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jukka Ruohonen.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include "macros.h"
34 
35 #include <sys/cdefs.h>
36 __RCSID("$NetBSD: t_kill.c,v 1.1 2011/07/07 06:57:53 jruoho Exp $");
37 
38 #include <sys/wait.h>
39 
40 #include <errno.h>
41 #include <limits.h>
42 #include <pwd.h>
43 #include <signal.h>
44 #include <stdlib.h>
45 #include <unistd.h>
46 
47 #include "atf-c.h"
48 
49 ATF_TC(kill_basic);
50 ATF_TC_HEAD(kill_basic, tc)
51 {
52 	atf_tc_set_md_var(tc, "descr", "Test that kill(2) works");
53 }
54 
55 ATF_TC_BODY(kill_basic, tc)
56 {
57 	const int sig[] = { SIGHUP, SIGINT, SIGKILL, SIGTERM };
58 	pid_t pid;
59 	size_t i;
60 	int sta;
61 
62 	for (i = 0; i < __arraycount(sig); i++) {
63 		struct sigaction act, oact;
64 
65 		/* Ensure the signal is not ignored. */
66 		if (sig[i] != SIGKILL) {
67 			memset(&act, 0, sizeof(act));
68 			act.sa_handler = SIG_DFL;
69 			ATF_REQUIRE(sigaction(sig[i], &act, &oact) == 0);
70 		} else {
71 			ATF_REQUIRE(sigaction(sig[i], &act, &oact) != 0);
72 			ATF_REQUIRE(errno == EINVAL);
73 		}
74 
75 		pid = fork();
76 		ATF_REQUIRE(pid >= 0);
77 
78 		switch (pid) {
79 
80 		case 0:
81 			pause();
82 			break;
83 
84 		default:
85 			ATF_REQUIRE(kill(pid, sig[i]) == 0);
86 		}
87 
88 		(void)wait(&sta);
89 
90 		if (WIFSIGNALED(sta) == 0 || WTERMSIG(sta) != sig[i])
91 			atf_tc_fail("kill(2) failed to kill child");
92 
93 		if (sig[i] != SIGKILL)
94 			ATF_REQUIRE(sigaction(sig[i], &oact, NULL) == 0);
95 	}
96 }
97 
98 ATF_TC(kill_err);
99 ATF_TC_HEAD(kill_err, tc)
100 {
101 	atf_tc_set_md_var(tc, "descr", "Test error conditions of kill(2)");
102 }
103 
104 ATF_TC_BODY(kill_err, tc)
105 {
106 	int rv, sta;
107 	pid_t pid;
108 
109 	pid = fork();
110 	ATF_REQUIRE(pid >= 0);
111 
112 	if (pid == 0) {
113 
114 		errno = 0;
115 		rv = kill(getpid(), -1);
116 
117 		if (rv == 0 || errno != EINVAL)
118 			_exit(EINVAL);
119 
120 		errno = 0;
121 		rv = kill(INT_MAX, SIGUSR1);
122 
123 		if (rv == 0 || errno != ESRCH)
124 			_exit(ESRCH);
125 
126 		_exit(EXIT_SUCCESS);
127 	}
128 
129 	(void)wait(&sta);
130 
131 	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS) {
132 
133 		if (WEXITSTATUS(sta) == EINVAL)
134 			atf_tc_fail("expected EINVAL, but kill(2) succeeded");
135 
136 		if (WEXITSTATUS(sta) == ESRCH)
137 			atf_tc_fail("expected ESRCH, but kill(2) succeeded");
138 
139 		atf_tc_fail("unknown error from kill(2)");
140 	}
141 }
142 
143 ATF_TC(kill_perm);
144 ATF_TC_HEAD(kill_perm, tc)
145 {
146 	atf_tc_set_md_var(tc, "descr", "Test kill(2) permissions");
147 	atf_tc_set_md_var(tc, "require.user", "root");
148 }
149 
150 ATF_TC_BODY(kill_perm, tc)
151 {
152 	struct passwd *pw;
153 	pid_t cpid, ppid;
154 	uid_t cuid = 0;
155 	uid_t puid = 0;
156 	int sta;
157 
158 	/*
159 	 * Test that kill(2) fails when called
160 	 * for a PID owned by another user.
161 	 */
162 	pw = getpwnam("operator");
163 
164 	if (pw != NULL)
165 		cuid = pw->pw_uid;
166 
167 	pw = getpwnam("nobody");
168 
169 	if (pw != NULL)
170 		puid = pw->pw_uid;
171 
172 	if (cuid == 0 || puid == 0 || cuid == puid)
173 		atf_tc_fail("getpwnam(3) failed");
174 
175 	ppid = fork();
176 
177 	if (ppid < 0)
178 		_exit(EXIT_FAILURE);
179 
180 	if (ppid == 0) {
181 
182 		cpid = fork();
183 
184 		if (cpid < 0)
185 			_exit(EXIT_FAILURE);
186 
187 		if (cpid == 0) {
188 
189 			if (setuid(cuid) < 0)
190 				_exit(EXIT_FAILURE);
191 			else {
192 				(void)sleep(1);
193 			}
194 
195 			_exit(EXIT_SUCCESS);
196 		}
197 
198 		/*
199 		 * Try to kill the child after having
200 		 * set the real and effective UID.
201 		 */
202 		if (setuid(puid) != 0)
203 			_exit(EXIT_FAILURE);
204 
205 		errno = 0;
206 
207 		if (kill(cpid, SIGKILL) == 0)
208 			_exit(EPERM);
209 
210 		if (errno != EPERM)
211 			_exit(EPERM);
212 
213 		(void)waitpid(cpid, &sta, 0);
214 
215 		_exit(EXIT_SUCCESS);
216 	}
217 
218 	(void)waitpid(ppid, &sta, 0);
219 
220 	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) == EPERM)
221 		atf_tc_fail("killed a process of another user");
222 
223 	if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
224 		atf_tc_fail("unknown error from kill(2)");
225 }
226 
227 ATF_TC(kill_pgrp_neg);
228 ATF_TC_HEAD(kill_pgrp_neg, tc)
229 {
230 	atf_tc_set_md_var(tc, "descr", "Test kill(2) with process group, #2");
231 }
232 
233 ATF_TC_BODY(kill_pgrp_neg, tc)
234 {
235 	const int maxiter = 3;
236 	pid_t cpid, ppid;
237 	int i, sta;
238 
239 	ppid = fork();
240 	ATF_REQUIRE(ppid >= 0);
241 
242 	if (ppid == 0) {
243 
244 		ATF_REQUIRE(setpgid(0, 0) == 0);
245 
246 		for (i = 0; i < maxiter; i++) {
247 
248 			cpid = fork();
249 			ATF_REQUIRE(cpid >= 0);
250 
251 			if (cpid == 0)
252 				pause();
253 		}
254 
255 		/*
256 		 * Test the variant of killpg(3); if the process number
257 		 * is negative but not -1, the signal should be sent to
258 		 * all processes whose process group ID is equal to the
259 		 * absolute value of the process number.
260 		 */
261 		ATF_REQUIRE(kill(-getpgrp(), SIGKILL) == 0);
262 
263 		(void)sleep(1);
264 
265 		_exit(EXIT_SUCCESS);
266 	}
267 
268 	(void)waitpid(ppid, &sta, 0);
269 
270 	if (WIFSIGNALED(sta) == 0 || WTERMSIG(sta) != SIGKILL)
271 		atf_tc_fail("failed to kill(2) a process group");
272 }
273 
274 ATF_TC(kill_pgrp_zero);
275 ATF_TC_HEAD(kill_pgrp_zero, tc)
276 {
277 	atf_tc_set_md_var(tc, "descr", "Test kill(2) with process group, #1");
278 }
279 
280 ATF_TC_BODY(kill_pgrp_zero, tc)
281 {
282 	const int maxiter = 3;
283 	pid_t cpid, ppid;
284 	int i, sta;
285 
286 	ppid = fork();
287 	ATF_REQUIRE(ppid >= 0);
288 
289 	if (ppid == 0) {
290 
291 		ATF_REQUIRE(setpgid(0, 0) == 0);
292 
293 		for (i = 0; i < maxiter; i++) {
294 
295 			cpid = fork();
296 			ATF_REQUIRE(cpid >= 0);
297 
298 			if (cpid == 0)
299 				pause();
300 		}
301 
302 		/*
303 		 * If the supplied process number is zero,
304 		 * the signal should be sent to all processes
305 		 * under the current process group.
306 		 */
307 		ATF_REQUIRE(kill(0, SIGKILL) == 0);
308 
309 		(void)sleep(1);
310 
311 		_exit(EXIT_SUCCESS);
312 	}
313 
314 	(void)waitpid(ppid, &sta, 0);
315 
316 	if (WIFSIGNALED(sta) == 0 || WTERMSIG(sta) != SIGKILL)
317 		atf_tc_fail("failed to kill(2) a process group");
318 }
319 
320 ATF_TP_ADD_TCS(tp)
321 {
322 
323 	ATF_TP_ADD_TC(tp, kill_basic);
324 	ATF_TP_ADD_TC(tp, kill_err);
325 	ATF_TP_ADD_TC(tp, kill_perm);
326 	ATF_TP_ADD_TC(tp, kill_pgrp_neg);
327 	ATF_TP_ADD_TC(tp, kill_pgrp_zero);
328 
329 	return atf_no_error();
330 }
331