xref: /freebsd/usr.bin/posixshmcontrol/posixshmcontrol.c (revision f6a3b357e9be4c6423c85eff9a847163a0d307c8)
1 /*-
2  * Copyright (c) 2019 The FreeBSD Foundation
3  *
4  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
5  * under sponsorship from the FreeBSD Foundation.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/mman.h>
34 #include <sys/stat.h>
35 #include <sys/sysctl.h>
36 #include <sys/user.h>
37 #include <err.h>
38 #include <fcntl.h>
39 #include <grp.h>
40 #include <libutil.h>
41 #include <pwd.h>
42 #include <stdbool.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47 
48 static void
49 usage(void)
50 {
51 
52 	fprintf(stderr, "Usage:\n"
53 	    "posixshmcontrol create [-m <mode>] <path> ...\n"
54 	    "posixshmcontrol rm <path> ...\n"
55 	    "posixshmcontrol ls [-h] [-n]\n"
56 	    "posixshmcontrol dump <path> ...\n"
57 	    "posixshmcontrol stat [-h] [-n] <path> ...\n"
58 	    "posixshmcontrol truncate [-s <newlen>] <path> ...\n");
59 }
60 
61 static int
62 create_one_shm(const char *path, long mode)
63 {
64 	int fd;
65 
66 	fd = shm_open(path, O_RDWR | O_CREAT, mode);
67 	if (fd == -1) {
68 		warn("create %s", path);
69 		return (1);
70 	}
71 	close(fd);
72 	return (0);
73 }
74 
75 static int
76 create_shm(int argc, char **argv)
77 {
78 	char *end;
79 	long mode;
80 	int c, i, ret, ret1;
81 
82 	mode = 0600;
83 	while ((c = getopt(argc, argv, "m:")) != -1) {
84 		switch (c) {
85 		case 'm':
86 			errno = 0;
87 			mode = strtol(optarg, &end, 0);
88 			if (mode == 0 && errno != 0)
89 				err(1, "mode:");
90 			if (*end != '\0')
91 				errx(1, "non-integer mode");
92 			break;
93 		case '?':
94 		default:
95 			usage();
96 			return (2);
97 		}
98 	}
99 
100 	argc -= optind;
101 	argv += optind;
102 	ret = 0;
103 	for (i = 0; i < argc; i++) {
104 		ret1 = create_one_shm(argv[i], mode);
105 		if (ret1 != 0 && ret == 0)
106 			ret = ret1;
107 	}
108 	return (ret);
109 }
110 
111 static int
112 delete_one_shm(const char *path)
113 {
114 	int error, ret;
115 
116 	error = shm_unlink(path);
117 	if (error != 0) {
118 		warn("unlink of %s failed", path);
119 		ret = 1;
120 	} else {
121 		ret = 0;
122 	}
123 	return (ret);
124 }
125 
126 static int
127 delete_shm(int argc, char **argv)
128 {
129 	int i, ret, ret1;
130 
131 	ret = 0;
132 	for (i = 1; i < argc; i++) {
133 		ret1 = delete_one_shm(argv[i]);
134 		if (ret1 != 0 && ret == 0)
135 			ret = ret1;
136 	}
137 	return (ret);
138 }
139 
140 static const char listmib[] = "kern.ipc.posix_shm_list";
141 
142 static void
143 shm_decode_mode(mode_t m, char *str)
144 {
145 	int i;
146 
147 	i = 0;
148 	str[i++] = (m & S_IRUSR) != 0 ? 'r' : '-';
149 	str[i++] = (m & S_IWUSR) != 0 ? 'w' : '-';
150 	str[i++] = (m & S_IXUSR) != 0 ? 'x' : '-';
151 	str[i++] = (m & S_IRGRP) != 0 ? 'r' : '-';
152 	str[i++] = (m & S_IWGRP) != 0 ? 'w' : '-';
153 	str[i++] = (m & S_IXGRP) != 0 ? 'x' : '-';
154 	str[i++] = (m & S_IROTH) != 0 ? 'r' : '-';
155 	str[i++] = (m & S_IWOTH) != 0 ? 'w' : '-';
156 	str[i++] = (m & S_IXOTH) != 0 ? 'x' : '-';
157 	str[i] = '\0';
158 }
159 
160 static int
161 list_shm(int argc, char **argv)
162 {
163 	char *buf, *bp, sizebuf[8], str[10];
164 	const struct kinfo_file *kif;
165 	struct stat st;
166 	int c, error, fd, mib[3], ret;
167 	size_t len, miblen;
168 	bool hsize, uname;
169 
170 	hsize = false;
171 	uname = true;
172 
173 	while ((c = getopt(argc, argv, "hn")) != -1) {
174 		switch (c) {
175 		case 'h':
176 			hsize = true;
177 			break;
178 		case 'n':
179 			uname = false;
180 			break;
181 		default:
182 			usage();
183 			return (2);
184 		}
185 	}
186 	if (argc != optind) {
187 		usage();
188 		return (2);
189 	}
190 
191 	miblen = nitems(mib);
192 	error = sysctlnametomib(listmib, mib, &miblen);
193 	if (error == -1) {
194 		warn("cannot translate %s", listmib);
195 		return (1);
196 	}
197 	len = 0;
198 	error = sysctl(mib, miblen, NULL, &len, NULL, 0);
199 	if (error == -1) {
200 		warn("cannot get %s length", listmib);
201 		return (1);
202 	}
203 	len = len * 4 / 3;
204 	buf = malloc(len);
205 	if (buf == NULL) {
206 		warn("malloc");
207 		return (1);
208 	}
209 	error = sysctl(mib, miblen, buf, &len, NULL, 0);
210 	if (error != 0) {
211 		warn("reading %s", listmib);
212 		ret = 1;
213 		goto out;
214 	}
215 	ret = 0;
216 	printf("MODE    \tOWNER\tGROUP\tSIZE\tPATH\n");
217 	for (bp = buf; bp < buf + len; bp += kif->kf_structsize) {
218 		kif = (const struct kinfo_file *)(void *)bp;
219 		if (kif->kf_structsize == 0)
220 			break;
221 		fd = shm_open(kif->kf_path, O_RDONLY, 0);
222 		if (fd == -1) {
223 			warn("open %s", kif->kf_path);
224 			ret = 1;
225 			continue;
226 		}
227 		error = fstat(fd, &st);
228 		close(fd);
229 		if (error != 0) {
230 			warn("stat %s", kif->kf_path);
231 			ret = 1;
232 			continue;
233 		}
234 		shm_decode_mode(kif->kf_un.kf_file.kf_file_mode, str);
235 		printf("%s\t", str);
236 		if (uname) {
237 			printf("%s\t%s\t", user_from_uid(st.st_uid, 0),
238 			    group_from_gid(st.st_gid, 0));
239 		} else {
240 			printf("%d\t%d\t", st.st_uid, st.st_gid);
241 		}
242 		if (hsize) {
243 			humanize_number(sizebuf, sizeof(sizebuf),
244 			    kif->kf_un.kf_file.kf_file_size, "", HN_AUTOSCALE,
245 			    HN_NOSPACE);
246 			printf("%s\t", sizebuf);
247 		} else {
248 			printf("%jd\t",
249 			    (uintmax_t)kif->kf_un.kf_file.kf_file_size);
250 		}
251 		printf("%s\n", kif->kf_path);
252 	}
253 out:
254 	free(buf);
255 	return (ret);
256 }
257 
258 static int
259 read_one_shm(const char *path)
260 {
261 	char buf[4096];
262 	ssize_t size, se;
263 	int fd, ret;
264 
265 	ret = 1;
266 	fd = shm_open(path, O_RDONLY, 0);
267 	if (fd == -1) {
268 		warn("open %s", path);
269 		goto out;
270 	}
271 	for (;;) {
272 		size = read(fd, buf, sizeof(buf));
273 		if (size > 0) {
274 			se = fwrite(buf, 1, size, stdout);
275 			if (se < size) {
276 				warnx("short write to stdout");
277 				goto out;
278 			}
279 		}
280 		if (size == (ssize_t)sizeof(buf))
281 			continue;
282 		if (size >= 0 && size < (ssize_t)sizeof(buf)) {
283 			ret = 0;
284 			goto out;
285 		}
286 		warn("read from %s", path);
287 		goto out;
288 	}
289 out:
290 	close(fd);
291 	return (ret);
292 }
293 
294 static int
295 read_shm(int argc, char **argv)
296 {
297 	int i, ret, ret1;
298 
299 	ret = 0;
300 	for (i = 1; i < argc; i++) {
301 		ret1 = read_one_shm(argv[i]);
302 		if (ret1 != 0 && ret == 0)
303 			ret = ret1;
304 	}
305 	return (ret);
306 }
307 
308 static int
309 stat_one_shm(const char *path, bool hsize, bool uname)
310 {
311 	char sizebuf[8];
312 	struct stat st;
313 	int error, fd, ret;
314 
315 	fd = shm_open(path, O_RDONLY, 0);
316 	if (fd == -1) {
317 		warn("open %s", path);
318 		return (1);
319 	}
320 	ret = 0;
321 	error = fstat(fd, &st);
322 	if (error == -1) {
323 		warn("stat %s", path);
324 		ret = 1;
325 	} else {
326 		printf("path\t%s\n", path);
327 		printf("inode\t%jd\n", (uintmax_t)st.st_ino);
328 		printf("mode\t%#o\n", st.st_mode);
329 		printf("nlink\t%jd\n", (uintmax_t)st.st_nlink);
330 		if (uname) {
331 			printf("owner\t%s\n", user_from_uid(st.st_uid, 0));
332 			printf("group\t%s\n", group_from_gid(st.st_gid, 0));
333 		} else {
334 			printf("uid\t%d\n", st.st_uid);
335 			printf("gid\t%d\n", st.st_gid);
336 		}
337 		if (hsize) {
338 			humanize_number(sizebuf, sizeof(sizebuf),
339 			    st.st_size, "", HN_AUTOSCALE, HN_NOSPACE);
340 			printf("size\t%s\n", sizebuf);
341 		} else {
342 			printf("size\t%jd\n", (uintmax_t)st.st_size);
343 		}
344 		printf("atime\t%ld.%09ld\n", (long)st.st_atime,
345 		    (long)st.st_atim.tv_nsec);
346 		printf("mtime\t%ld.%09ld\n", (long)st.st_mtime,
347 		    (long)st.st_mtim.tv_nsec);
348 		printf("ctime\t%ld.%09ld\n", (long)st.st_ctime,
349 		    (long)st.st_ctim.tv_nsec);
350 		printf("birth\t%ld.%09ld\n", (long)st.st_birthtim.tv_sec,
351 		    (long)st.st_birthtim.tv_nsec);
352 	}
353 	close(fd);
354 	return (ret);
355 }
356 
357 static int
358 stat_shm(int argc, char **argv)
359 {
360 	int c, i, ret, ret1;
361 	bool hsize, uname;
362 
363 	hsize = false;
364 	uname = true;
365 
366 	while ((c = getopt(argc, argv, "hn")) != -1) {
367 		switch (c) {
368 		case 'h':
369 			hsize = true;
370 			break;
371 		case 'n':
372 			uname = false;
373 			break;
374 		default:
375 			usage();
376 			return (2);
377 		}
378 	}
379 	argc -= optind;
380 	argv += optind;
381 
382 	ret = 0;
383 	for (i = 0; i < argc; i++) {
384 		ret1 = stat_one_shm(argv[i], hsize, uname);
385 		if (ret1 != 0 && ret == 0)
386 			ret = ret1;
387 	}
388 	return (ret);
389 }
390 
391 static int
392 truncate_one_shm(const char *path, uint64_t newsize)
393 {
394 	int error, fd, ret;
395 
396 	ret = 0;
397 	fd = shm_open(path, O_RDWR, 0);
398 	if (fd == -1) {
399 		warn("open %s", path);
400 		return (1);
401 	}
402 	error = ftruncate(fd, newsize);
403 	if (error == -1) {
404 		warn("truncate %s", path);
405 		ret = 1;
406 	}
407 	close(fd);
408 	return (ret);
409 }
410 
411 static int
412 truncate_shm(int argc, char **argv)
413 {
414 	uint64_t newsize;
415 	int c, i, ret, ret1;
416 
417 	newsize = 0;
418 	while ((c = getopt(argc, argv, "s:")) != -1) {
419 		switch (c) {
420 		case 's':
421 			if (expand_number(optarg, &newsize) == -1)
422 				err(1, "size:");
423 			break;
424 		case '?':
425 		default:
426 			return (2);
427 		}
428 	}
429 
430 	argc -= optind;
431 	argv += optind;
432 	ret = 0;
433 	for (i = 0; i < argc; i++) {
434 		ret1 = truncate_one_shm(argv[i], newsize);
435 		if (ret1 != 0 && ret == 0)
436 			ret = ret1;
437 	}
438 	return (ret);
439 }
440 
441 struct opmode {
442 	const char *cmd;
443 	int (*impl)(int argc, char **argv);
444 };
445 
446 static const struct opmode opmodes[] = {
447 	{ .cmd = "create",	.impl = create_shm},
448 	{ .cmd = "rm",		.impl = delete_shm, },
449 	{ .cmd = "ls",		.impl = list_shm },
450 	{ .cmd = "dump",	.impl = read_shm, },
451 	{ .cmd = "stat",	.impl = stat_shm, },
452 	{ .cmd = "truncate",	.impl = truncate_shm, },
453 };
454 
455 int
456 main(int argc, char *argv[])
457 {
458 	const struct opmode *opmode;
459 	int i, ret;
460 
461 	ret = 0;
462 	opmode = NULL;
463 
464 	if (argc < 2) {
465 		usage();
466 		exit(2);
467 	}
468 	for (i = 0; i < (int)nitems(opmodes); i++) {
469 		if (strcmp(argv[1], opmodes[i].cmd) == 0) {
470 			opmode = &opmodes[i];
471 			break;
472 		}
473 	}
474 	if (opmode == NULL) {
475 		usage();
476 		exit(2);
477 	}
478 	ret = opmode->impl(argc - 1, argv + 1);
479 	exit(ret);
480 }
481