xref: /netbsd/tests/modules/t_modctl.c (revision 08055463)
1 /*	$NetBSD: t_modctl.c,v 1.16 2020/02/22 19:54:34 pgoyette Exp $	*/
2 /*
3  * Copyright (c) 2008 The NetBSD Foundation, Inc.
4  * All rights reserved.
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 NETBSD FOUNDATION, INC. AND
16  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
17  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY
20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
22  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
24  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
25  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
26  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: t_modctl.c,v 1.16 2020/02/22 19:54:34 pgoyette Exp $");
31 
32 #include <sys/module.h>
33 #include <sys/sysctl.h>
34 
35 #include <assert.h>
36 #include <errno.h>
37 #include <stdarg.h>
38 #include <stdbool.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <sys/evcnt.h>
43 
44 #include <prop/proplib.h>
45 
46 #include <atf-c.h>
47 
48 enum presence_check { all_checks, stat_check, sysctl_check, evcnt_check };
49 
50 static void	check_permission(void);
51 static bool	get_modstat_info(const char *, modstat_t *);
52 static bool	get_sysctl(const char *, void *buf, const size_t);
53 static bool	k_helper_is_present_stat(void);
54 static bool	k_helper_is_present_sysctl(void);
55 static bool	k_helper_is_present_evcnt(void);
56 static bool	k_helper_is_present(enum presence_check);
57 static int	load(prop_dictionary_t, bool, const char *, ...);
58 static int	unload(const char *, bool);
59 static void	unload_cleanup(const char *);
60 
61 /* --------------------------------------------------------------------- */
62 /* Auxiliary functions                                                   */
63 /* --------------------------------------------------------------------- */
64 
65 /*
66  * A function checking whether we are allowed to load modules currently
67  * (either the kernel is not modular, or securelevel may prevent it)
68  */
69 static void
check_permission(void)70 check_permission(void)
71 {
72 	int err;
73 
74 	err = modctl(MODCTL_EXISTS, 0);
75 	if (err == 0) return;
76 	if (errno == ENOSYS)
77 		atf_tc_skip("Kernel does not have 'options MODULAR'.");
78 	else if (errno == EPERM)
79 		atf_tc_skip("Module loading administratively forbidden");
80 	ATF_REQUIRE_EQ_MSG(errno, 0, "unexpected error %d from "
81 	    "modctl(MODCTL_EXISTS, 0)", errno);
82 }
83 
84 static bool
get_modstat_info(const char * name,modstat_t * msdest)85 get_modstat_info(const char *name, modstat_t *msdest)
86 {
87 	bool found;
88 	size_t len;
89 	int count;
90 	struct iovec iov;
91 	modstat_t *ms;
92 	modstat_t m;
93 
94 	check_permission();
95 	for (len = 8192; ;) {
96 		iov.iov_base = malloc(len);
97 		iov.iov_len = len;
98 
99 		errno = 0;
100 
101 		if (modctl(MODCTL_STAT, &iov) != 0) {
102 			int err = errno;
103 			fprintf(stderr, "modctl(MODCTL_STAT) failed: %s\n",
104 			    strerror(err));
105 			atf_tc_fail("Failed to query module status");
106 		}
107 		if (len >= iov.iov_len)
108 			break;
109 		free(iov.iov_base);
110 		len = iov.iov_len;
111 	}
112 
113 	found = false;
114 	count = *(int *)iov.iov_base;
115 	ms = (modstat_t *)((char *)iov.iov_base + sizeof(int));
116 	while ( count ) {
117 		memcpy(&m, ms, sizeof(m));
118 		if (strcmp(m.ms_name, name) == 0) {
119 			if (msdest != NULL)
120 				memcpy(msdest, &m, sizeof(*msdest));
121 			found = true;
122 			break;
123 		}
124 		ms++;
125 		count--;
126 	}
127 
128 	free(iov.iov_base);
129 
130 	return found;
131 }
132 
133 /*
134  * Queries a sysctl property.
135  */
136 static bool
get_sysctl(const char * name,void * buf,const size_t len)137 get_sysctl(const char *name, void *buf, const size_t len)
138 {
139 	size_t len2 = len;
140 	printf("Querying sysctl variable: %s\n", name);
141 	int ret = sysctlbyname(name, buf, &len2, NULL, 0);
142 	if (ret == -1 && errno != ENOENT) {
143 		fprintf(stderr, "sysctlbyname(2) failed: %s\n",
144 		    strerror(errno));
145 		atf_tc_fail("Failed to query %s", name);
146 	}
147 	return ret != -1;
148 }
149 
150 /*
151  * Returns a boolean indicating if the k_helper module was loaded
152  * successfully.  This implementation uses modctl(2)'s MODCTL_STAT
153  * subcommand to do the check.
154  */
155 static bool
k_helper_is_present_stat(void)156 k_helper_is_present_stat(void)
157 {
158 
159 	return get_modstat_info("k_helper", NULL);
160 }
161 
162 /*
163  * Returns a boolean indicating if the k_helper module was loaded
164  * successfully.  This implementation uses the module's sysctl
165  * installed node to do the check.
166  */
167 static bool
k_helper_is_present_sysctl(void)168 k_helper_is_present_sysctl(void)
169 {
170 	size_t present;
171 
172 	return get_sysctl("vendor.k_helper.present", &present,
173 	    sizeof(present));
174 }
175 
176 /*
177  * Returns a boolean indicating if the k_helper module was loaded
178  * successfully.  This implementation uses the module's evcnt
179  * to do the check.
180  */
181 static bool
k_helper_is_present_evcnt(void)182 k_helper_is_present_evcnt(void)
183 {
184 	const int mib[4] = {CTL_KERN, KERN_EVCNT, EVCNT_TYPE_ANY,
185 	    KERN_EVCNT_COUNT_ANY };
186 	int error;
187 	size_t newlen, buflen = 0;
188 	void *buf0, *buf = NULL;
189 	const struct evcnt_sysctl *evs, *last_evs;
190 
191 	for (;;) {
192 		if (buflen)
193 			buf = malloc(buflen);
194 		error = sysctl(mib, __arraycount(mib), buf, &newlen, NULL, 0);
195 		if (error) {
196 			if (buf)
197 				free(buf);
198 			return false;
199 		}
200 		if (newlen <= buflen) {
201 			buflen = newlen;
202 			break;
203 		}
204 		if (buf)
205 			free(buf);
206 		buflen = newlen;
207 	}
208 	evs = buf0 = buf;
209 	last_evs = (void *)((char *)buf + buflen);
210 	buflen /= sizeof(uint64_t);
211 	while (evs < last_evs
212 	    && buflen >= sizeof(*evs)/sizeof(uint64_t)
213 	    && buflen >= evs->ev_len) {
214 		if ( strncmp(evs->ev_strings, "k_helper", evs->ev_grouplen)
215 		    == 0) {
216 			free(buf);
217 			return true;
218 		}
219 		buflen -= evs->ev_len;
220 		evs = (const void *)((const uint64_t *)evs + evs->ev_len);
221 	}
222 	free(buf);
223 	return false;
224 }
225 
226 /*
227  * Returns a boolean indicating if the k_helper module was loaded
228  * successfully.  The 'how' parameter specifies the implementation to
229  * use to do the check.
230  */
231 static bool
k_helper_is_present(enum presence_check how)232 k_helper_is_present(enum presence_check how)
233 {
234 	bool found;
235 
236 	switch (how) {
237 	case all_checks:
238 		found = k_helper_is_present_stat();
239 		ATF_CHECK(k_helper_is_present_sysctl() == found);
240 		ATF_CHECK(k_helper_is_present_evcnt() == found);
241 		break;
242 
243 	case stat_check:
244 		found = k_helper_is_present_stat();
245 		break;
246 
247 	case sysctl_check:
248 		found = k_helper_is_present_sysctl();
249 		break;
250 
251 	case evcnt_check:
252 		found = k_helper_is_present_evcnt();
253 		break;
254 
255 	default:
256 		found = false;
257 		assert(found);
258 	}
259 
260 	return found;
261 }
262 
263 /*
264  * Loads the specified module from a file.  If fatal is set and an error
265  * occurs when loading the module, an error message is printed and the
266  * test case is aborted.
267  */
268 static __printflike(3, 4) int
load(prop_dictionary_t props,bool fatal,const char * fmt,...)269 load(prop_dictionary_t props, bool fatal, const char *fmt, ...)
270 {
271 	int err;
272 	va_list ap;
273 	char filename[MAXPATHLEN], *propsstr;
274 	modctl_load_t ml;
275 
276 	check_permission();
277 	if (props == NULL) {
278 		props = prop_dictionary_create();
279 		propsstr = prop_dictionary_externalize(props);
280 		ATF_CHECK(propsstr != NULL);
281 		prop_object_release(props);
282 	} else {
283 		propsstr = prop_dictionary_externalize(props);
284 		ATF_CHECK(propsstr != NULL);
285 	}
286 
287 	va_start(ap, fmt);
288 	vsnprintf(filename, sizeof(filename), fmt, ap);
289 	va_end(ap);
290 
291 	ml.ml_filename = filename;
292 	ml.ml_flags = 0;
293 	ml.ml_props = propsstr;
294 	ml.ml_propslen = strlen(propsstr);
295 
296 	printf("Loading module %s\n", filename);
297 	errno = err = 0;
298 
299 	if (modctl(MODCTL_LOAD, &ml) == -1) {
300 		err = errno;
301 		fprintf(stderr, "modctl(MODCTL_LOAD, %s), failed: %s\n",
302 		    filename, strerror(err));
303 		if (fatal)
304 			atf_tc_fail("Module load failed");
305 	}
306 
307 	free(propsstr);
308 
309 	return err;
310 }
311 
312 /*
313  * Unloads the specified module.  If silent is true, nothing will be
314  * printed and no errors will be raised if the unload was unsuccessful.
315  */
316 static int
unload(const char * name,bool fatal)317 unload(const char *name, bool fatal)
318 {
319 	int err;
320 
321 	check_permission();
322 	printf("Unloading module %s\n", name);
323 	errno = err = 0;
324 
325 	if (modctl(MODCTL_UNLOAD, __UNCONST(name)) == -1) {
326 		err = errno;
327 		fprintf(stderr, "modctl(MODCTL_UNLOAD, %s) failed: %s\n",
328 		    name, strerror(err));
329 		if (fatal)
330 			atf_tc_fail("Module unload failed");
331 	}
332 	return err;
333 }
334 
335 /*
336  * A silent version of unload, to be called as part of the cleanup
337  * process only.
338  */
339 static void
unload_cleanup(const char * name)340 unload_cleanup(const char *name)
341 {
342 
343 	(void)modctl(MODCTL_UNLOAD, __UNCONST(name));
344 }
345 
346 /* --------------------------------------------------------------------- */
347 /* Test cases                                                            */
348 /* --------------------------------------------------------------------- */
349 
350 ATF_TC_WITH_CLEANUP(cmd_load);
ATF_TC_HEAD(cmd_load,tc)351 ATF_TC_HEAD(cmd_load, tc)
352 {
353 	atf_tc_set_md_var(tc, "descr", "Tests for the MODCTL_LOAD command");
354 	atf_tc_set_md_var(tc, "require.user", "root");
355 }
ATF_TC_BODY(cmd_load,tc)356 ATF_TC_BODY(cmd_load, tc)
357 {
358 	char longname[MAXPATHLEN];
359 	size_t i;
360 
361 	ATF_CHECK(load(NULL, false, " ") == ENOENT);
362 	ATF_CHECK(load(NULL, false, "non-existent.o") == ENOENT);
363 
364 	for (i = 0; i < MAXPATHLEN - 1; i++)
365 		longname[i] = 'a';
366 	longname[MAXPATHLEN - 1] = '\0';
367 	ATF_CHECK(load(NULL, false, "%s", longname) == ENAMETOOLONG);
368 
369 	ATF_CHECK(!k_helper_is_present(stat_check));
370 	load(NULL, true, "%s/k_helper/k_helper.kmod",
371 	    atf_tc_get_config_var(tc, "srcdir"));
372 	printf("Checking if load was successful\n");
373 	ATF_CHECK(k_helper_is_present(stat_check));
374 }
ATF_TC_CLEANUP(cmd_load,tc)375 ATF_TC_CLEANUP(cmd_load, tc)
376 {
377 	unload_cleanup("k_helper");
378 }
379 
380 ATF_TC_WITH_CLEANUP(cmd_load_props);
ATF_TC_HEAD(cmd_load_props,tc)381 ATF_TC_HEAD(cmd_load_props, tc)
382 {
383 	atf_tc_set_md_var(tc, "descr", "Tests for the MODCTL_LOAD command, "
384 	    "providing extra load-time properties");
385 	atf_tc_set_md_var(tc, "require.user", "root");
386 }
ATF_TC_BODY(cmd_load_props,tc)387 ATF_TC_BODY(cmd_load_props, tc)
388 {
389 	prop_dictionary_t props;
390 
391 	printf("Loading module without properties\n");
392 	props = prop_dictionary_create();
393 	load(props, true, "%s/k_helper/k_helper.kmod",
394 	    atf_tc_get_config_var(tc, "srcdir"));
395 	prop_object_release(props);
396 	{
397 		int ok;
398 		ATF_CHECK(get_sysctl("vendor.k_helper.prop_str_ok",
399 		    &ok, sizeof(ok)));
400 		ATF_CHECK(!ok);
401 	}
402 	unload("k_helper", true);
403 
404 	printf("Loading module with a string property\n");
405 	props = prop_dictionary_create();
406 	prop_dictionary_set(props, "prop_str",
407 	    prop_string_create_cstring("1st string"));
408 	load(props, true, "%s/k_helper/k_helper.kmod",
409 	    atf_tc_get_config_var(tc, "srcdir"));
410 	prop_object_release(props);
411 	{
412 		int ok;
413 		ATF_CHECK(get_sysctl("vendor.k_helper.prop_str_ok",
414 		    &ok, sizeof(ok)));
415 		ATF_CHECK(ok);
416 
417 		char val[128];
418 		ATF_CHECK(get_sysctl("vendor.k_helper.prop_str_val",
419 		    &val, sizeof(val)));
420 		ATF_CHECK(strcmp(val, "1st string") == 0);
421 	}
422 	unload("k_helper", true);
423 
424 	printf("Loading module with a different string property\n");
425 	props = prop_dictionary_create();
426 	prop_dictionary_set(props, "prop_str",
427 	    prop_string_create_cstring("2nd string"));
428 	load(props, true, "%s/k_helper/k_helper.kmod",
429 	    atf_tc_get_config_var(tc, "srcdir"));
430 	prop_object_release(props);
431 	{
432 		int ok;
433 		ATF_CHECK(get_sysctl("vendor.k_helper.prop_str_ok",
434 		    &ok, sizeof(ok)));
435 		ATF_CHECK(ok);
436 
437 		char val[128];
438 		ATF_CHECK(get_sysctl("vendor.k_helper.prop_str_val",
439 		    &val, sizeof(val)));
440 		ATF_CHECK(strcmp(val, "2nd string") == 0);
441 	}
442 	unload("k_helper", true);
443 }
ATF_TC_CLEANUP(cmd_load_props,tc)444 ATF_TC_CLEANUP(cmd_load_props, tc)
445 {
446 	unload_cleanup("k_helper");
447 }
448 
449 ATF_TC_WITH_CLEANUP(cmd_load_recurse);
ATF_TC_HEAD(cmd_load_recurse,tc)450 ATF_TC_HEAD(cmd_load_recurse, tc)
451 {
452 	atf_tc_set_md_var(tc, "descr", "Tests for the MODCTL_LOAD command, "
453 	    "with recursive module_load()");
454 	atf_tc_set_md_var(tc, "require.user", "root");
455 }
ATF_TC_BODY(cmd_load_recurse,tc)456 ATF_TC_BODY(cmd_load_recurse, tc)
457 {
458 	prop_dictionary_t props;
459 	char filename[MAXPATHLEN];
460 
461 	printf("Loading module with request to load another module\n");
462 	props = prop_dictionary_create();
463 	snprintf(filename, sizeof(filename), "%s/k_helper2/k_helper2.kmod",
464 	    atf_tc_get_config_var(tc, "srcdir"));
465 	prop_dictionary_set(props, "prop_recurse",
466 	    prop_string_create_cstring(filename));
467 	load(props, true, "%s/k_helper/k_helper.kmod",
468 	    atf_tc_get_config_var(tc, "srcdir"));
469 	{
470 		int ok;
471 		ATF_CHECK(get_sysctl("vendor.k_helper.prop_int_load",
472 		    &ok, sizeof(ok)));
473 		ATF_CHECK(ok == 0);
474 		ATF_CHECK(get_sysctl("vendor.k_helper2.present",
475 		    &ok, sizeof(ok)));
476 		ATF_CHECK(ok);
477 	}
478 	unload("k_helper", true);
479 	unload("k_helper2", true);
480 }
ATF_TC_CLEANUP(cmd_load_recurse,tc)481 ATF_TC_CLEANUP(cmd_load_recurse, tc)
482 {
483 	unload_cleanup("k_helper");
484 	unload_cleanup("k_helper2");
485 }
486 
487 ATF_TC_WITH_CLEANUP(cmd_stat);
ATF_TC_HEAD(cmd_stat,tc)488 ATF_TC_HEAD(cmd_stat, tc)
489 {
490 	atf_tc_set_md_var(tc, "descr", "Tests for the MODCTL_STAT command");
491 	atf_tc_set_md_var(tc, "require.user", "root");
492 }
ATF_TC_BODY(cmd_stat,tc)493 ATF_TC_BODY(cmd_stat, tc)
494 {
495 	ATF_CHECK(!k_helper_is_present(all_checks));
496 
497 	load(NULL, true, "%s/k_helper/k_helper.kmod",
498 	    atf_tc_get_config_var(tc, "srcdir"));
499 	ATF_CHECK(k_helper_is_present(all_checks));
500 	{
501 		modstat_t ms;
502 		ATF_CHECK(get_modstat_info("k_helper", &ms));
503 
504 		ATF_CHECK(ms.ms_class == MODULE_CLASS_MISC);
505 		ATF_CHECK(ms.ms_source == MODULE_SOURCE_FILESYS);
506 		ATF_CHECK(ms.ms_refcnt == 0);
507 	}
508 	unload("k_helper", true);
509 
510 	ATF_CHECK(!k_helper_is_present(all_checks));
511 }
ATF_TC_CLEANUP(cmd_stat,tc)512 ATF_TC_CLEANUP(cmd_stat, tc)
513 {
514 	unload_cleanup("k_helper");
515 }
516 
517 ATF_TC_WITH_CLEANUP(cmd_unload);
ATF_TC_HEAD(cmd_unload,tc)518 ATF_TC_HEAD(cmd_unload, tc)
519 {
520 	atf_tc_set_md_var(tc, "descr", "Tests for the MODCTL_UNLOAD command");
521 	atf_tc_set_md_var(tc, "require.user", "root");
522 }
ATF_TC_BODY(cmd_unload,tc)523 ATF_TC_BODY(cmd_unload, tc)
524 {
525 	load(NULL, true, "%s/k_helper/k_helper.kmod",
526 	    atf_tc_get_config_var(tc, "srcdir"));
527 
528 	ATF_CHECK(unload("", false) == ENOENT);
529 	ATF_CHECK(unload("non-existent.kmod", false) == ENOENT);
530 	ATF_CHECK(unload("k_helper.kmod", false) == ENOENT);
531 
532 	ATF_CHECK(k_helper_is_present(stat_check));
533 	unload("k_helper", true);
534 	printf("Checking if unload was successful\n");
535 	ATF_CHECK(!k_helper_is_present(stat_check));
536 }
ATF_TC_CLEANUP(cmd_unload,tc)537 ATF_TC_CLEANUP(cmd_unload, tc)
538 {
539 	unload_cleanup("k_helper");
540 }
541 
542 /* --------------------------------------------------------------------- */
543 /* Main                                                                  */
544 /* --------------------------------------------------------------------- */
545 
ATF_TP_ADD_TCS(tp)546 ATF_TP_ADD_TCS(tp)
547 {
548 
549 	ATF_TP_ADD_TC(tp, cmd_load);
550 	ATF_TP_ADD_TC(tp, cmd_load_props);
551 	ATF_TP_ADD_TC(tp, cmd_stat);
552 	ATF_TP_ADD_TC(tp, cmd_load_recurse);
553 	ATF_TP_ADD_TC(tp, cmd_unload);
554 
555 	return atf_no_error();
556 }
557