xref: /freebsd/lib/libproc/tests/proc_test.c (revision bd81e07d2761cf1c13063eb49a5c0cb4a6951318)
1 /*-
2  * Copyright (c) 2014, 2015 Mark Johnston <markj@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/types.h>
31 #include <sys/wait.h>
32 
33 #include <libgen.h>
34 #include <stdio.h>
35 #include <stdint.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <atf-c.h>
39 #include <libelf.h>
40 #include <libproc.h>
41 
42 static const char *aout_object = "a.out";
43 #if !defined(__aarch64__)
44 static const char *ldelf_object = "ld-elf.so.1";
45 #endif
46 static const char *target_prog_file = "target_prog";
47 
48 /*
49  * Run the test program. If the sig parameter is set to true, the test program
50  * will deliver SIGUSR1 to itself during execution.
51  */
52 static struct proc_handle *
53 start_prog(const struct atf_tc *tc, bool sig)
54 {
55 	char *argv[3];
56 	struct proc_handle *phdl;
57 	int error;
58 
59 	asprintf(&argv[0], "%s/%s", atf_tc_get_config_var(tc, "srcdir"),
60 	    target_prog_file);
61 	ATF_REQUIRE(argv[0] != NULL);
62 
63 	if (sig) {
64 		argv[1] = strdup("-s");
65 		argv[2] = NULL;
66 	} else {
67 		argv[1] = NULL;
68 	}
69 
70 	error = proc_create(argv[0], argv, NULL, NULL, &phdl);
71 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to run '%s'", target_prog_file);
72 	ATF_REQUIRE(phdl != NULL);
73 
74 	free(argv[0]);
75 	free(argv[1]);
76 
77 	return (phdl);
78 }
79 
80 #if !defined(__aarch64__)
81 static void
82 set_bkpt(struct proc_handle *phdl, uintptr_t addr, u_long *saved)
83 {
84 	int error;
85 
86 	error = proc_bkptset(phdl, addr, saved);
87 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to set breakpoint at 0x%jx",
88 	    (uintmax_t)addr);
89 }
90 
91 static void
92 remove_bkpt(struct proc_handle *phdl, uintptr_t addr, u_long val)
93 {
94 	int error;
95 
96 	error = proc_bkptdel(phdl, addr, val);
97 	ATF_REQUIRE_EQ_MSG(error, 0,
98 	    "failed to delete breakpoint at 0x%jx", (uintmax_t)addr);
99 
100 	error = proc_regset(phdl, REG_PC, addr);
101 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to reset program counter");
102 }
103 
104 /*
105  * Wait for the specified process to hit a breakpoint at the specified symbol.
106  */
107 static void
108 verify_bkpt(struct proc_handle *phdl, GElf_Sym *sym, const char *symname,
109     const char *mapname)
110 {
111 	char mapbname[MAXPATHLEN], *name;
112 	GElf_Sym tsym;
113 	prmap_t *map;
114 	size_t namesz;
115 	u_long addr;
116 	int error, state;
117 
118 	state = proc_wstatus(phdl);
119 	ATF_REQUIRE_EQ_MSG(state, PS_STOP, "process has state %d", state);
120 
121 	/* Get the program counter and decrement it. */
122 	error = proc_regget(phdl, REG_PC, &addr);
123 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to obtain PC for '%s'",
124 	    target_prog_file);
125 	proc_bkptregadj(&addr);
126 
127 	/*
128 	 * Make sure the PC matches the expected value obtained from the symbol
129 	 * definition we looked up earlier.
130 	 */
131 	ATF_CHECK_EQ_MSG(addr, sym->st_value,
132 	    "program counter 0x%lx doesn't match expected value 0x%jx",
133 	    addr, (uintmax_t)sym->st_value);
134 
135 	/*
136 	 * Ensure we can look up the r_debug_state symbol using its starting
137 	 * address and that the resulting symbol matches the one we found using
138 	 * a name lookup.
139 	 */
140 	namesz = strlen(symname) + 1;
141 	name = malloc(namesz);
142 	ATF_REQUIRE(name != NULL);
143 
144 	error = proc_addr2sym(phdl, addr, name, namesz, &tsym);
145 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up symbol at 0x%lx", addr);
146 	ATF_REQUIRE_EQ(memcmp(sym, &tsym, sizeof(*sym)), 0);
147 	ATF_REQUIRE_EQ(strcmp(symname, name), 0);
148 	free(name);
149 
150 	map = proc_addr2map(phdl, addr);
151 	ATF_REQUIRE_MSG(map != NULL, "failed to look up map for address 0x%lx",
152 	    addr);
153 	basename_r(map->pr_mapname, mapbname);
154 	ATF_REQUIRE_EQ_MSG(strcmp(mapname, mapbname), 0,
155 	    "expected map name '%s' doesn't match '%s'", mapname, mapbname);
156 }
157 #endif
158 
159 ATF_TC(map_alias_obj2map);
160 ATF_TC_HEAD(map_alias_obj2map, tc)
161 {
162 	atf_tc_set_md_var(tc, "descr",
163 	    "Callers are supposed to be able to use \"a.out\" as an alias for "
164 	    "the program executable. Make sure that proc_obj2map() handles "
165 	    "this properly.");
166 }
167 ATF_TC_BODY(map_alias_obj2map, tc)
168 {
169 	struct proc_handle *phdl;
170 	prmap_t *map1, *map2;
171 
172 	phdl = start_prog(tc, false);
173 
174 	/* Initialize the rtld_db handle. */
175 	(void)proc_rdagent(phdl);
176 
177 	/* Ensure that "target_prog" and "a.out" return the same map. */
178 	map1 = proc_obj2map(phdl, target_prog_file);
179 	ATF_REQUIRE_MSG(map1 != NULL, "failed to look up map for '%s'",
180 	    target_prog_file);
181 	map2 = proc_obj2map(phdl, aout_object);
182 	ATF_REQUIRE_MSG(map2 != NULL, "failed to look up map for '%s'",
183 	    aout_object);
184 	ATF_CHECK_EQ(strcmp(map1->pr_mapname, map2->pr_mapname), 0);
185 
186 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
187 
188 	proc_free(phdl);
189 }
190 
191 ATF_TC(map_alias_name2map);
192 ATF_TC_HEAD(map_alias_name2map, tc)
193 {
194 	atf_tc_set_md_var(tc, "descr",
195 	    "Callers are supposed to be able to use \"a.out\" as an alias for "
196 	    "the program executable. Make sure that proc_name2map() handles "
197 	    "this properly.");
198 }
199 ATF_TC_BODY(map_alias_name2map, tc)
200 {
201 	struct proc_handle *phdl;
202 	prmap_t *map1, *map2;
203 
204 	phdl = start_prog(tc, false);
205 
206 	/* Initialize the rtld_db handle. */
207 	(void)proc_rdagent(phdl);
208 
209 	/* Ensure that "target_prog" and "a.out" return the same map. */
210 	map1 = proc_name2map(phdl, target_prog_file);
211 	ATF_REQUIRE_MSG(map1 != NULL, "failed to look up map for '%s'",
212 	    target_prog_file);
213 	map2 = proc_name2map(phdl, aout_object);
214 	ATF_REQUIRE_MSG(map2 != NULL, "failed to look up map for '%s'",
215 	    aout_object);
216 	ATF_CHECK_EQ(strcmp(map1->pr_mapname, map2->pr_mapname), 0);
217 
218 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
219 
220 	proc_free(phdl);
221 }
222 
223 ATF_TC(map_alias_name2sym);
224 ATF_TC_HEAD(map_alias_name2sym, tc)
225 {
226 	atf_tc_set_md_var(tc, "descr",
227 	    "Callers are supposed to be able to use \"a.out\" as an alias for "
228 	    "the program executable. Make sure that proc_name2sym() handles "
229 	    "this properly.");
230 }
231 ATF_TC_BODY(map_alias_name2sym, tc)
232 {
233 	GElf_Sym sym1, sym2;
234 	prsyminfo_t si1, si2;
235 	struct proc_handle *phdl;
236 	int error;
237 
238 	phdl = start_prog(tc, false);
239 
240 	/* Initialize the rtld_db handle. */
241 	(void)proc_rdagent(phdl);
242 
243 	/*
244 	 * Make sure that "target_prog:main" and "a.out:main" return the same
245 	 * symbol.
246 	 */
247 	error = proc_name2sym(phdl, target_prog_file, "main", &sym1, &si1);
248 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'main' via %s",
249 	    target_prog_file);
250 	error = proc_name2sym(phdl, aout_object, "main", &sym2, &si2);
251 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'main' via %s",
252 	    aout_object);
253 
254 	ATF_CHECK_EQ(memcmp(&sym1, &sym2, sizeof(sym1)), 0);
255 	ATF_CHECK_EQ(si1.prs_id, si2.prs_id);
256 
257 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
258 
259 	proc_free(phdl);
260 }
261 
262 #if !defined(__aarch64__)
263 ATF_TC(symbol_lookup);
264 ATF_TC_HEAD(symbol_lookup, tc)
265 {
266 	atf_tc_set_md_var(tc, "descr",
267 	    "Look up a couple of well-known symbols in the test program, place "
268 	    "breakpoints on them, and verify that we hit the breakpoints. Also "
269 	    "make sure that we can use the breakpoint address to look up the "
270 	    "corresponding symbol.");
271 }
272 ATF_TC_BODY(symbol_lookup, tc)
273 {
274 	GElf_Sym main_sym, r_debug_state_sym;
275 	struct proc_handle *phdl;
276 	u_long saved;
277 	int error;
278 
279 	phdl = start_prog(tc, false);
280 
281 	error = proc_name2sym(phdl, target_prog_file, "main", &main_sym, NULL);
282 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'main'");
283 
284 	error = proc_name2sym(phdl, ldelf_object, "r_debug_state",
285 	    &r_debug_state_sym, NULL);
286 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'r_debug_state'");
287 
288 	set_bkpt(phdl, r_debug_state_sym.st_value, &saved);
289 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
290 	verify_bkpt(phdl, &r_debug_state_sym, "r_debug_state", ldelf_object);
291 	remove_bkpt(phdl, r_debug_state_sym.st_value, saved);
292 
293 	set_bkpt(phdl, main_sym.st_value, &saved);
294 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
295 	verify_bkpt(phdl, &main_sym, "main", target_prog_file);
296 	remove_bkpt(phdl, main_sym.st_value, saved);
297 
298 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
299 
300 	proc_free(phdl);
301 }
302 
303 ATF_TC(symbol_lookup_fail);
304 ATF_TC_HEAD(symbol_lookup_fail, tc)
305 {
306 	atf_tc_set_md_var(tc, "descr",
307 	    "Verify that proc_addr2sym() returns an error when given an offset "
308 	    "that it cannot resolve.");
309 }
310 ATF_TC_BODY(symbol_lookup_fail, tc)
311 {
312 	char symname[32];
313 	GElf_Sym sym;
314 	struct proc_handle *phdl;
315 	prmap_t *map;
316 	int error;
317 
318 	phdl = start_prog(tc, false);
319 
320 	/* Initialize the rtld_db handle. */
321 	(void)proc_rdagent(phdl);
322 
323 	map = proc_obj2map(phdl, target_prog_file);
324 	ATF_REQUIRE_MSG(map != NULL, "failed to look up map for '%s'",
325 	    target_prog_file);
326 
327 	/*
328 	 * We shouldn't be able to find symbols at the beginning of a mapped
329 	 * file.
330 	 */
331 	error = proc_addr2sym(phdl, map->pr_vaddr, symname, sizeof(symname),
332 	    &sym);
333 	ATF_REQUIRE_MSG(error != 0, "unexpectedly found a symbol");
334 
335 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
336 
337 	proc_free(phdl);
338 }
339 #endif
340 
341 ATF_TC(signal_forward);
342 ATF_TC_HEAD(signal_forward, tc)
343 {
344 	atf_tc_set_md_var(tc, "descr",
345 	    "Run the test program in a mode which causes it to send a signal "
346 	    "to itself. Make sure that we intercept the signal and that "
347 	    "proc_continue() forwards it to the process.");
348 }
349 ATF_TC_BODY(signal_forward, tc)
350 {
351 	struct proc_handle *phdl;
352 	int state, status;
353 
354 	phdl = start_prog(tc, true);
355 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
356 
357 	/* The process should have been interrupted by a signal. */
358 	state = proc_wstatus(phdl);
359 	ATF_REQUIRE_EQ_MSG(state, PS_STOP, "process has unexpected state %d",
360 	    state);
361 
362 	/* Continue execution and allow the signal to be delivered. */
363 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
364 
365 	/*
366 	 * Make sure the process exited with status 0. If it didn't receive the
367 	 * SIGUSR1 that it sent to itself, it'll exit with a non-zero exit
368 	 * status, causing the test to fail.
369 	 */
370 	state = proc_wstatus(phdl);
371 	ATF_REQUIRE_EQ_MSG(state, PS_UNDEAD, "process has unexpected state %d",
372 	    state);
373 
374 	status = proc_getwstat(phdl);
375 	ATF_REQUIRE(status >= 0);
376 	ATF_REQUIRE(WIFEXITED(status));
377 	ATF_REQUIRE_EQ(WEXITSTATUS(status), 0);
378 
379 	proc_free(phdl);
380 }
381 
382 ATF_TP_ADD_TCS(tp)
383 {
384 
385 	ATF_TP_ADD_TC(tp, map_alias_obj2map);
386 	ATF_TP_ADD_TC(tp, map_alias_name2map);
387 	ATF_TP_ADD_TC(tp, map_alias_name2sym);
388 /* On arm64 triggers panic ARM64TODO: pmap_sync_icache (PR202305). */
389 #if !defined(__aarch64__)
390 	ATF_TP_ADD_TC(tp, symbol_lookup);
391 	ATF_TP_ADD_TC(tp, symbol_lookup_fail);
392 #endif
393 	ATF_TP_ADD_TC(tp, signal_forward);
394 
395 	return (atf_no_error());
396 }
397