1/*
2 * Copyright (c) Wipro Technologies Ltd, 2002.  All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of version 2 of the GNU General Public License as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it would be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11 *
12 * You should have received a copy of the GNU General Public License along
13 * with this program; if not, write the Free Software Foundation, Inc.,
14 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
15 *
16 */
17/**********************************************************
18 *
19 *    TEST IDENTIFIER	: ptrace02
20 *
21 *    EXECUTED BY	: anyone
22 *
23 *    TEST TITLE	: functionality test for ptrace(2)
24 *
25 *    TEST CASE TOTAL	: 2
26 *
27 *    AUTHOR		: Saji Kumar.V.R <saji.kumar@wipro.com>
28 *
29 *    SIGNALS
30 * 	Uses SIGUSR1 to pause before test if option set.
31 * 	(See the parse_opts(3) man page).
32 *
33 *    DESCRIPTION
34 *	This test case tests the functionality of ptrace() for
35 *	PTRACE_TRACEME & PTRACE_CONT requests.
36 *	Here, we fork a child & the child does ptrace(PTRACE_TRACEME, ...).
37 *	Then a signal is delivered to the child & verified that parent
38 *	is notified via wait(). then parent does ptrace(PTRACE_CONT, ..)
39 *	to make the child to continue. Again parent wait() for child to finish.
40 *	If child finished normally, test passes.
41 *		We test two cases
42 *			1) By telling child to ignore SIGUSR2 signal
43 *			2) By installing a signal handler for child for SIGUSR2
44 *		In both cases, child should stop & notify parent on reception
45 *		of SIGUSR2
46 *
47 * 	Setup:
48 * 	  Setup signal handling.
49 *	  Pause for SIGUSR1 if option specified.
50 *
51 * 	Test:
52 *	 Loop if the proper options are given.
53 *	 setup signal handler for SIGUSR2 signal
54 *	 fork a child
55 *
56 *	 CHILD:
57 *		setup signal handler for SIGUSR2 signal
58 *		call ptrace() with PTRACE_TRACEME request
59 *		send SIGUSR2 signal to self
60 *	 PARENT:
61 *		wait() for child.
62 *		if parent is notified when child gets a signal through wait(),
63 *		then
64 *			do  ptrace(PTRACE_CONT, ..) on child
65 * 			wait() for child to finish,
66 * 			if child exited normaly,
67 *				TEST passed
68 * 			else
69 * 				TEST failed
70 *		else
71 *			TEST failed
72 *
73 * 	Cleanup:
74 * 	  Print errno log and/or timing stats if options given
75 *
76 * USAGE:  <for command-line>
77 *  ptrace02 [-c n] [-e] [-i n] [-I x] [-P x] [-t] [-h] [-f] [-p]
78 *			where,  -c n : Run n copies concurrently.
79 *				-e   : Turn on errno logging.
80 *				-h   : Show help screen
81 *				-f   : Turn off functional testing
82 *				-i n : Execute test n times.
83 *				-I x : Execute test for x seconds.
84 *				-p   : Pause for SIGUSR1 before starting
85 *				-P x : Pause for x seconds between iterations.
86 *				-t   : Turn on syscall timing.
87 *
88 ****************************************************************/
89
90#include <errno.h>
91#include <signal.h>
92#include <sys/wait.h>
93
94#include <config.h>
95#include "ptrace.h"
96
97#include "test.h"
98
99static void do_child(void);
100static void setup(void);
101static void cleanup(void);
102static void child_handler();
103static void parent_handler();
104
105static int got_signal = 0;
106
107char *TCID = "ptrace02";
108static int i;			/* loop test case counter, shared with do_child */
109
110int TST_TOTAL = 2;
111
112int main(int ac, char **av)
113{
114
115	int lc;
116	pid_t child_pid;
117	int status;
118	struct sigaction parent_act;
119
120	tst_parse_opts(ac, av, NULL, NULL);
121#ifdef UCLINUX
122	maybe_run_child(&do_child, "d", &i);
123#endif
124
125	setup();
126
127	for (lc = 0; TEST_LOOPING(lc); lc++) {
128
129		tst_count = 0;
130
131		for (i = 0; i < TST_TOTAL; ++i) {
132			got_signal = 0;
133
134			/* Setup signal handler for parent */
135			if (i == 1) {
136				parent_act.sa_handler = parent_handler;
137				parent_act.sa_flags = SA_RESTART;
138				sigemptyset(&parent_act.sa_mask);
139
140				if ((sigaction(SIGUSR2, &parent_act, NULL))
141				    == -1) {
142					tst_resm(TWARN, "sigaction() failed"
143						 " in parent");
144					continue;
145				}
146			}
147
148			switch (child_pid = FORK_OR_VFORK()) {
149
150			case -1:
151				/* fork() failed */
152				tst_resm(TFAIL, "fork() failed");
153				continue;
154
155			case 0:
156				/* Child */
157#ifdef UCLINUX
158				if (self_exec(av[0], "d", i) < 0) {
159					tst_resm(TFAIL, "self_exec failed");
160					continue;
161				}
162#else
163				do_child();
164#endif
165
166			default:
167				/* Parent */
168				if ((waitpid(child_pid, &status, 0)) < 0) {
169					tst_resm(TFAIL, "waitpid() failed");
170					continue;
171				}
172
173				/*
174				 * Check the exit status of child. If (it exits
175				 * normally with exit value 1) OR (child came
176				 * through signal handler), Test Failed
177				 */
178
179				if (((WIFEXITED(status)) &&
180				     (WEXITSTATUS(status))) ||
181				    (got_signal == 1)) {
182					tst_resm(TFAIL, "Test Failed");
183					continue;
184				} else {
185					/* Restart child */
186					if ((ptrace(PTRACE_CONT, child_pid,
187						    0, 0)) == -1) {
188						tst_resm(TFAIL, "Test Failed:"
189							 " Parent was not able to do"
190							 " ptrace(PTRACE_CONT, ..) on"
191							 " child");
192						continue;
193					}
194				}
195
196				if ((waitpid(child_pid, &status, 0)) < 0) {
197					tst_resm(TFAIL, "waitpid() failed");
198					continue;
199				}
200
201				if (WIFEXITED(status)) {
202					/* Child exits normally */
203					tst_resm(TPASS, "Test Passed");
204				} else {
205					tst_resm(TFAIL, "Test Failed");
206				}
207
208			}
209		}
210	}
211
212	/* cleanup and exit */
213	cleanup();
214	tst_exit();
215
216}
217
218/* do_child() */
219void do_child(void)
220{
221	struct sigaction child_act;
222
223	/* Setup signal handler for child */
224	if (i == 0) {
225		child_act.sa_handler = SIG_IGN;
226	} else {
227		child_act.sa_handler = child_handler;
228	}
229	child_act.sa_flags = SA_RESTART;
230	sigemptyset(&child_act.sa_mask);
231
232	if ((sigaction(SIGUSR2, &child_act, NULL)) == -1) {
233		tst_resm(TWARN, "sigaction() failed in child");
234		exit(1);
235	}
236
237	if ((ptrace(PTRACE_TRACEME, 0, 0, 0)) == -1) {
238		tst_resm(TWARN, "ptrace() failed in child");
239		exit(1);
240	}
241
242	/* ensure that child bypasses signal handler */
243	if ((kill(getpid(), SIGUSR2)) == -1) {
244		tst_resm(TWARN, "kill() failed in child");
245		exit(1);
246	}
247	exit(1);
248}
249
250/* setup() - performs all ONE TIME setup for this test */
251void setup(void)
252{
253
254	tst_sig(FORK, DEF_HANDLER, cleanup);
255
256	TEST_PAUSE;
257
258}
259
260/*
261 *cleanup() -  performs all ONE TIME cleanup for this test at
262 *		completion or premature exit.
263 */
264void cleanup(void)
265{
266
267}
268
269/*
270 * child_handler() - Signal handler for child
271 */
272void child_handler(void)
273{
274
275	if ((kill(getppid(), SIGUSR2)) == -1) {
276		tst_resm(TWARN, "kill() failed in child_handler()");
277		exit(1);
278	}
279}
280
281/*
282 * parent_handler() - Signal handler for parent
283 */
284void parent_handler(void)
285{
286
287	got_signal = 1;
288}
289