xref: /freebsd/usr.bin/rctl/rctl.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
1 /*-
2  * Copyright (c) 2010 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Edward Tomasz Napierala under sponsorship
6  * from the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/types.h>
36 #include <sys/rctl.h>
37 #include <assert.h>
38 #include <ctype.h>
39 #include <err.h>
40 #include <errno.h>
41 #include <getopt.h>
42 #include <grp.h>
43 #include <libutil.h>
44 #include <pwd.h>
45 #include <stdint.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 
50 #define	RCTL_DEFAULT_BUFSIZE	4096
51 
52 static id_t
53 parse_user(const char *s)
54 {
55 	id_t id;
56 	char *end;
57 	struct passwd *pwd;
58 
59 	pwd = getpwnam(s);
60 	if (pwd != NULL)
61 		return (pwd->pw_uid);
62 
63 	if (!isnumber(s[0]))
64 		errx(1, "uknown user '%s'", s);
65 
66 	id = strtod(s, &end);
67 	if ((size_t)(end - s) != strlen(s))
68 		errx(1, "trailing characters after numerical id");
69 
70 	return (id);
71 }
72 
73 static id_t
74 parse_group(const char *s)
75 {
76 	id_t id;
77 	char *end;
78 	struct group *grp;
79 
80 	grp = getgrnam(s);
81 	if (grp != NULL)
82 		return (grp->gr_gid);
83 
84 	if (!isnumber(s[0]))
85 		errx(1, "uknown group '%s'", s);
86 
87 	id = strtod(s, &end);
88 	if ((size_t)(end - s) != strlen(s))
89 		errx(1, "trailing characters after numerical id");
90 
91 	return (id);
92 }
93 
94 /*
95  * This routine replaces user/group name with numeric id.
96  */
97 static char *
98 resolve_ids(char *rule)
99 {
100 	id_t id;
101 	const char *subject, *textid, *rest;
102 	char *resolved;
103 
104 	subject = strsep(&rule, ":");
105 	textid = strsep(&rule, ":");
106 	if (textid == NULL)
107 		errx(1, "error in rule specification -- no subject");
108 	if (rule != NULL)
109 		rest = rule;
110 	else
111 		rest = "";
112 
113 	if (strcasecmp(subject, "u") == 0)
114 		subject = "user";
115 	else if (strcasecmp(subject, "g") == 0)
116 		subject = "group";
117 	else if (strcasecmp(subject, "p") == 0)
118 		subject = "process";
119 	else if (strcasecmp(subject, "l") == 0 ||
120 	    strcasecmp(subject, "c") == 0 ||
121 	    strcasecmp(subject, "class") == 0)
122 		subject = "loginclass";
123 	else if (strcasecmp(subject, "j") == 0)
124 		subject = "jail";
125 
126 	if (strcasecmp(subject, "user") == 0 && strlen(textid) > 0) {
127 		id = parse_user(textid);
128 		asprintf(&resolved, "%s:%d:%s", subject, (int)id, rest);
129 	} else if (strcasecmp(subject, "group") == 0 && strlen(textid) > 0) {
130 		id = parse_group(textid);
131 		asprintf(&resolved, "%s:%d:%s", subject, (int)id, rest);
132 	} else
133 		asprintf(&resolved, "%s:%s:%s", subject, textid, rest);
134 
135 	if (resolved == NULL)
136 		err(1, "asprintf");
137 
138 	return (resolved);
139 }
140 
141 /*
142  * This routine replaces "human-readable" number with its expanded form.
143  */
144 static char *
145 expand_amount(char *rule)
146 {
147 	uint64_t num;
148 	const char *subject, *subject_id, *resource, *action, *amount, *per;
149 	char *copy, *expanded;
150 
151 	copy = strdup(rule);
152 	if (copy == NULL)
153 		err(1, "strdup");
154 
155 	subject = strsep(&copy, ":");
156 	subject_id = strsep(&copy, ":");
157 	resource = strsep(&copy, ":");
158 	action = strsep(&copy, "=/");
159 	amount = strsep(&copy, "/");
160 	per = copy;
161 
162 	if (amount == NULL || strlen(amount) == 0) {
163 		free(copy);
164 		return (rule);
165 	}
166 
167 	assert(subject != NULL);
168 	assert(subject_id != NULL);
169 	assert(resource != NULL);
170 	assert(action != NULL);
171 
172 	if (expand_number(amount, &num))
173 		err(1, "expand_number");
174 
175 	if (per == NULL)
176 		asprintf(&expanded, "%s:%s:%s:%s=%ju", subject, subject_id,
177 		    resource, action, (uintmax_t)num);
178 	else
179 		asprintf(&expanded, "%s:%s:%s:%s=%ju/%s", subject, subject_id,
180 		    resource, action, (uintmax_t)num, per);
181 
182 	if (expanded == NULL)
183 		err(1, "asprintf");
184 
185 	return (expanded);
186 }
187 
188 static char *
189 humanize_ids(char *rule)
190 {
191 	id_t id;
192 	struct passwd *pwd;
193 	struct group *grp;
194 	const char *subject, *textid, *rest;
195 	char *humanized;
196 
197 	subject = strsep(&rule, ":");
198 	textid = strsep(&rule, ":");
199 	if (textid == NULL)
200 		errx(1, "rule passed from the kernel didn't contain subject");
201 	if (rule != NULL)
202 		rest = rule;
203 	else
204 		rest = "";
205 
206 	/* Replace numerical user and group ids with names. */
207 	if (strcasecmp(subject, "user") == 0) {
208 		id = parse_user(textid);
209 		pwd = getpwuid(id);
210 		if (pwd != NULL)
211 			textid = pwd->pw_name;
212 	} else if (strcasecmp(subject, "group") == 0) {
213 		id = parse_group(textid);
214 		grp = getgrgid(id);
215 		if (grp != NULL)
216 			textid = grp->gr_name;
217 	}
218 
219 	asprintf(&humanized, "%s:%s:%s", subject, textid, rest);
220 
221 	if (humanized == NULL)
222 		err(1, "asprintf");
223 
224 	return (humanized);
225 }
226 
227 static int
228 str2int64(const char *str, int64_t *value)
229 {
230 	char *end;
231 
232 	if (str == NULL)
233 		return (EINVAL);
234 
235 	*value = strtoul(str, &end, 10);
236 	if ((size_t)(end - str) != strlen(str))
237 		return (EINVAL);
238 
239 	return (0);
240 }
241 
242 static char *
243 humanize_amount(char *rule)
244 {
245 	int64_t num;
246 	const char *subject, *subject_id, *resource, *action, *amount, *per;
247 	char *copy, *humanized, buf[6];
248 
249 	copy = strdup(rule);
250 	if (copy == NULL)
251 		err(1, "strdup");
252 
253 	subject = strsep(&copy, ":");
254 	subject_id = strsep(&copy, ":");
255 	resource = strsep(&copy, ":");
256 	action = strsep(&copy, "=/");
257 	amount = strsep(&copy, "/");
258 	per = copy;
259 
260 	if (amount == NULL || strlen(amount) == 0 ||
261 	    str2int64(amount, &num) != 0) {
262 		free(copy);
263 		return (rule);
264 	}
265 
266 	assert(subject != NULL);
267 	assert(subject_id != NULL);
268 	assert(resource != NULL);
269 	assert(action != NULL);
270 
271 	if (humanize_number(buf, sizeof(buf), num, "", HN_AUTOSCALE,
272 	    HN_DECIMAL | HN_NOSPACE) == -1)
273 		err(1, "humanize_number");
274 
275 	if (per == NULL)
276 		asprintf(&humanized, "%s:%s:%s:%s=%s", subject, subject_id,
277 		    resource, action, buf);
278 	else
279 		asprintf(&humanized, "%s:%s:%s:%s=%s/%s", subject, subject_id,
280 		    resource, action, buf, per);
281 
282 	if (humanized == NULL)
283 		err(1, "asprintf");
284 
285 	return (humanized);
286 }
287 
288 /*
289  * Print rules, one per line.
290  */
291 static void
292 print_rules(char *rules, int hflag, int nflag)
293 {
294 	char *rule;
295 
296 	while ((rule = strsep(&rules, ",")) != NULL) {
297 		if (rule[0] == '\0')
298 			break; /* XXX */
299 		if (nflag == 0)
300 			rule = humanize_ids(rule);
301 		if (hflag)
302 			rule = humanize_amount(rule);
303 		printf("%s\n", rule);
304 	}
305 }
306 
307 static void
308 add_rule(char *rule)
309 {
310 	int error;
311 
312 	error = rctl_add_rule(rule, strlen(rule) + 1, NULL, 0);
313 	if (error != 0)
314 		err(1, "rctl_add_rule");
315 	free(rule);
316 }
317 
318 static void
319 show_limits(char *filter, int hflag, int nflag)
320 {
321 	int error;
322 	char *outbuf = NULL;
323 	size_t outbuflen = RCTL_DEFAULT_BUFSIZE / 4;
324 
325 	do {
326 		outbuflen *= 4;
327 		outbuf = realloc(outbuf, outbuflen);
328 		if (outbuf == NULL)
329 			err(1, "realloc");
330 
331 		error = rctl_get_limits(filter, strlen(filter) + 1, outbuf,
332 		    outbuflen);
333 		if (error && errno != ERANGE)
334 			err(1, "rctl_get_limits");
335 	} while (error && errno == ERANGE);
336 
337 	print_rules(outbuf, hflag, nflag);
338 	free(filter);
339 	free(outbuf);
340 }
341 
342 static void
343 remove_rule(char *filter)
344 {
345 	int error;
346 
347 	error = rctl_remove_rule(filter, strlen(filter) + 1, NULL, 0);
348 	if (error != 0)
349 		err(1, "rctl_remove_rule");
350 	free(filter);
351 }
352 
353 static char *
354 humanize_usage_amount(char *usage)
355 {
356 	int64_t num;
357 	const char *resource, *amount;
358 	char *copy, *humanized, buf[6];
359 
360 	copy = strdup(usage);
361 	if (copy == NULL)
362 		err(1, "strdup");
363 
364 	resource = strsep(&copy, "=");
365 	amount = copy;
366 
367 	assert(resource != NULL);
368 	assert(amount != NULL);
369 
370 	if (str2int64(amount, &num) != 0 ||
371 	    humanize_number(buf, sizeof(buf), num, "", HN_AUTOSCALE,
372 	    HN_DECIMAL | HN_NOSPACE) == -1) {
373 		free(copy);
374 		return (usage);
375 	}
376 
377 	asprintf(&humanized, "%s=%s", resource, buf);
378 	if (humanized == NULL)
379 		err(1, "asprintf");
380 
381 	return (humanized);
382 }
383 
384 /*
385  * Query the kernel about a resource usage and print it out.
386  */
387 static void
388 show_usage(char *filter, int hflag)
389 {
390 	int error;
391 	char *outbuf = NULL, *tmp;
392 	size_t outbuflen = RCTL_DEFAULT_BUFSIZE / 4;
393 
394 	do {
395 		outbuflen *= 4;
396 		outbuf = realloc(outbuf, outbuflen);
397 		if (outbuf == NULL)
398 			err(1, "realloc");
399 
400 		error = rctl_get_racct(filter, strlen(filter) + 1, outbuf,
401 		    outbuflen);
402 		if (error && errno != ERANGE)
403 			err(1, "rctl_get_racct");
404 	} while (error && errno == ERANGE);
405 
406 	while ((tmp = strsep(&outbuf, ",")) != NULL) {
407 		if (tmp[0] == '\0')
408 			break; /* XXX */
409 
410 		if (hflag)
411 			tmp = humanize_usage_amount(tmp);
412 
413 		printf("%s\n", tmp);
414 	}
415 
416 	free(filter);
417 	free(outbuf);
418 }
419 
420 /*
421  * Query the kernel about resource limit rules and print them out.
422  */
423 static void
424 show_rules(char *filter, int hflag, int nflag)
425 {
426 	int error;
427 	char *outbuf = NULL;
428 	size_t filterlen, outbuflen = RCTL_DEFAULT_BUFSIZE / 4;
429 
430 	if (filter != NULL)
431 		filterlen = strlen(filter) + 1;
432 	else
433 		filterlen = 0;
434 
435 	do {
436 		outbuflen *= 4;
437 		outbuf = realloc(outbuf, outbuflen);
438 		if (outbuf == NULL)
439 			err(1, "realloc");
440 
441 		error = rctl_get_rules(filter, filterlen, outbuf, outbuflen);
442 		if (error && errno != ERANGE)
443 			err(1, "rctl_get_rules");
444 	} while (error && errno == ERANGE);
445 
446 	print_rules(outbuf, hflag, nflag);
447 	free(outbuf);
448 }
449 
450 static void
451 usage(void)
452 {
453 
454 	fprintf(stderr, "usage: rctl [ -h ] [-a rule | -l filter | -r filter "
455 	    "| -u filter | filter]\n");
456 	exit(1);
457 }
458 
459 int
460 main(int argc __unused, char **argv __unused)
461 {
462 	int ch, aflag = 0, hflag = 0, nflag = 0, lflag = 0, rflag = 0,
463 	    uflag = 0;
464 	char *rule = NULL;
465 
466 	while ((ch = getopt(argc, argv, "a:hl:nr:u:")) != -1) {
467 		switch (ch) {
468 		case 'a':
469 			aflag = 1;
470 			rule = strdup(optarg);
471 			break;
472 		case 'h':
473 			hflag = 1;
474 			break;
475 		case 'l':
476 			lflag = 1;
477 			rule = strdup(optarg);
478 			break;
479 		case 'n':
480 			nflag = 1;
481 			break;
482 		case 'r':
483 			rflag = 1;
484 			rule = strdup(optarg);
485 			break;
486 		case 'u':
487 			uflag = 1;
488 			rule = strdup(optarg);
489 			break;
490 
491 		case '?':
492 		default:
493 			usage();
494 		}
495 	}
496 
497 	argc -= optind;
498 	argv += optind;
499 
500 	if (argc > 1)
501 		usage();
502 
503 	if (rule == NULL) {
504 		if (argc == 1)
505 			rule = strdup(argv[0]);
506 		else
507 			rule = strdup("::");
508 	}
509 
510 	if (aflag + lflag + rflag + uflag + argc > 1)
511 		errx(1, "only one flag or argument may be specified "
512 		    "at the same time");
513 
514 	rule = resolve_ids(rule);
515 	rule = expand_amount(rule);
516 
517 	if (aflag) {
518 		add_rule(rule);
519 		return (0);
520 	}
521 
522 	if (lflag) {
523 		show_limits(rule, hflag, nflag);
524 		return (0);
525 	}
526 
527 	if (rflag) {
528 		remove_rule(rule);
529 		return (0);
530 	}
531 
532 	if (uflag) {
533 		show_usage(rule, hflag);
534 		return (0);
535 	}
536 
537 	show_rules(rule, hflag, nflag);
538 	return (0);
539 }
540