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path: root/runit/chpst.c (plain)
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1/*
2Copyright (c) 2001-2006, Gerrit Pape
3All rights reserved.
4
5Redistribution and use in source and binary forms, with or without
6modification, are permitted provided that the following conditions are met:
7
8 1. Redistributions of source code must retain the above copyright notice,
9 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 3. The name of the author may not be used to endorse or promote products
14 derived from this software without specific prior written permission.
15
16THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
17WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
18MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
19EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
22OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
25ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26*/
27
28/* Busyboxed by Denys Vlasenko <vda.linux@googlemail.com> */
29/* Dependencies on runit_lib.c removed */
30
31//usage:#define chpst_trivial_usage
32//usage: "[-vP012] [-u USER[:GRP]] [-U USER[:GRP]] [-e DIR]\n"
33//usage: " [-/ DIR] [-n NICE] [-m BYTES] [-d BYTES] [-o N]\n"
34//usage: " [-p N] [-f BYTES] [-c BYTES] PROG ARGS"
35//usage:#define chpst_full_usage "\n\n"
36//usage: "Change the process state, run PROG\n"
37//usage: "\n -u USER[:GRP] Set uid and gid"
38//usage: "\n -U USER[:GRP] Set $UID and $GID in environment"
39//usage: "\n -e DIR Set environment variables as specified by files"
40//usage: "\n in DIR: file=1st_line_of_file"
41//usage: "\n -/ DIR Chroot to DIR"
42//usage: "\n -n NICE Add NICE to nice value"
43//usage: "\n -m BYTES Same as -d BYTES -s BYTES -l BYTES"
44//usage: "\n -d BYTES Limit data segment"
45//usage: "\n -o N Limit number of open files per process"
46//usage: "\n -p N Limit number of processes per uid"
47//usage: "\n -f BYTES Limit output file sizes"
48//usage: "\n -c BYTES Limit core file size"
49//usage: "\n -v Verbose"
50//usage: "\n -P Create new process group"
51//usage: "\n -0 Close stdin"
52//usage: "\n -1 Close stdout"
53//usage: "\n -2 Close stderr"
54//usage:
55//usage:#define envdir_trivial_usage
56//usage: "DIR PROG ARGS"
57//usage:#define envdir_full_usage "\n\n"
58//usage: "Set various environment variables as specified by files\n"
59//usage: "in the directory DIR, run PROG"
60//usage:
61//usage:#define envuidgid_trivial_usage
62//usage: "USER PROG ARGS"
63//usage:#define envuidgid_full_usage "\n\n"
64//usage: "Set $UID to USER's uid and $GID to USER's gid, run PROG"
65//usage:
66//usage:#define setuidgid_trivial_usage
67//usage: "USER PROG ARGS"
68//usage:#define setuidgid_full_usage "\n\n"
69//usage: "Set uid and gid to USER's uid and gid, drop supplementary group ids,\n"
70//usage: "run PROG"
71//usage:
72//usage:#define softlimit_trivial_usage
73//usage: "[-a BYTES] [-m BYTES] [-d BYTES] [-s BYTES] [-l BYTES]\n"
74//usage: " [-f BYTES] [-c BYTES] [-r BYTES] [-o N] [-p N] [-t N]\n"
75//usage: " PROG ARGS"
76//usage:#define softlimit_full_usage "\n\n"
77//usage: "Set soft resource limits, then run PROG\n"
78//usage: "\n -a BYTES Limit total size of all segments"
79//usage: "\n -m BYTES Same as -d BYTES -s BYTES -l BYTES -a BYTES"
80//usage: "\n -d BYTES Limit data segment"
81//usage: "\n -s BYTES Limit stack segment"
82//usage: "\n -l BYTES Limit locked memory size"
83//usage: "\n -o N Limit number of open files per process"
84//usage: "\n -p N Limit number of processes per uid"
85//usage: "\nOptions controlling file sizes:"
86//usage: "\n -f BYTES Limit output file sizes"
87//usage: "\n -c BYTES Limit core file size"
88//usage: "\nEfficiency opts:"
89//usage: "\n -r BYTES Limit resident set size"
90//usage: "\n -t N Limit CPU time, process receives"
91//usage: "\n a SIGXCPU after N seconds"
92
93#include "libbb.h"
94#include <sys/resource.h> /* getrlimit */
95
96/*
97Five applets here: chpst, envdir, envuidgid, setuidgid, softlimit.
98
99Only softlimit and chpst are taking options:
100
101# common
102-o N Limit number of open files per process
103-p N Limit number of processes per uid
104-m BYTES Same as -d BYTES -s BYTES -l BYTES [-a BYTES]
105-d BYTES Limit data segment
106-f BYTES Limit output file sizes
107-c BYTES Limit core file size
108# softlimit
109-a BYTES Limit total size of all segments
110-s BYTES Limit stack segment
111-l BYTES Limit locked memory size
112-r BYTES Limit resident set size
113-t N Limit CPU time
114# chpst
115-u USER[:GRP] Set uid and gid
116-U USER[:GRP] Set $UID and $GID in environment
117-e DIR Set environment variables as specified by files in DIR
118-/ DIR Chroot to DIR
119-n NICE Add NICE to nice value
120-v Verbose
121-P Create new process group
122-0 -1 -2 Close fd 0,1,2
123
124Even though we accept all these options for both softlimit and chpst,
125they are not to be advertised on their help texts.
126We have enough problems with feature creep in other people's
127software, don't want to add our own.
128
129envdir, envuidgid, setuidgid take no options, but they reuse code which
130handles -e, -U and -u.
131*/
132
133enum {
134 OPT_a = (1 << 0) * ENABLE_SOFTLIMIT,
135 OPT_c = (1 << 1) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
136 OPT_d = (1 << 2) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
137 OPT_f = (1 << 3) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
138 OPT_l = (1 << 4) * ENABLE_SOFTLIMIT,
139 OPT_m = (1 << 5) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
140 OPT_o = (1 << 6) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
141 OPT_p = (1 << 7) * (ENABLE_SOFTLIMIT || ENABLE_CHPST),
142 OPT_r = (1 << 8) * ENABLE_SOFTLIMIT,
143 OPT_s = (1 << 9) * ENABLE_SOFTLIMIT,
144 OPT_t = (1 << 10) * ENABLE_SOFTLIMIT,
145 OPT_u = (1 << 11) * (ENABLE_CHPST || ENABLE_SETUIDGID),
146 OPT_U = (1 << 12) * (ENABLE_CHPST || ENABLE_ENVUIDGID),
147 OPT_e = (1 << 13) * (ENABLE_CHPST || ENABLE_ENVDIR),
148 OPT_root = (1 << 14) * ENABLE_CHPST,
149 OPT_n = (1 << 15) * ENABLE_CHPST,
150 OPT_v = (1 << 16) * ENABLE_CHPST,
151 OPT_P = (1 << 17) * ENABLE_CHPST,
152 OPT_0 = (1 << 18) * ENABLE_CHPST,
153 OPT_1 = (1 << 19) * ENABLE_CHPST,
154 OPT_2 = (1 << 20) * ENABLE_CHPST,
155};
156
157/* TODO: use recursive_action? */
158static NOINLINE void edir(const char *directory_name)
159{
160 int wdir;
161 DIR *dir;
162 struct dirent *d;
163 int fd;
164
165 wdir = xopen(".", O_RDONLY | O_NDELAY);
166 xchdir(directory_name);
167 dir = xopendir(".");
168 for (;;) {
169 char buf[256];
170 char *tail;
171 int size;
172
173 errno = 0;
174 d = readdir(dir);
175 if (!d) {
176 if (errno)
177 bb_perror_msg_and_die("readdir %s",
178 directory_name);
179 break;
180 }
181 if (d->d_name[0] == '.')
182 continue;
183 fd = open(d->d_name, O_RDONLY | O_NDELAY);
184 if (fd < 0) {
185 if ((errno == EISDIR) && directory_name) {
186 if (option_mask32 & OPT_v)
187 bb_perror_msg("warning: %s/%s is a directory",
188 directory_name, d->d_name);
189 continue;
190 }
191 bb_perror_msg_and_die("open %s/%s",
192 directory_name, d->d_name);
193 }
194 size = full_read(fd, buf, sizeof(buf)-1);
195 close(fd);
196 if (size < 0)
197 bb_perror_msg_and_die("read %s/%s",
198 directory_name, d->d_name);
199 if (size == 0) {
200 unsetenv(d->d_name);
201 continue;
202 }
203 buf[size] = '\n';
204 tail = strchr(buf, '\n');
205 /* skip trailing whitespace */
206 while (1) {
207 *tail = '\0';
208 tail--;
209 if (tail < buf || !isspace(*tail))
210 break;
211 }
212 xsetenv(d->d_name, buf);
213 }
214 closedir(dir);
215 if (fchdir(wdir) == -1)
216 bb_perror_msg_and_die("fchdir");
217 close(wdir);
218}
219
220static void limit(int what, long l)
221{
222 struct rlimit r;
223
224 /* Never fails under Linux (except if you pass it bad arguments) */
225 getrlimit(what, &r);
226 if ((l < 0) || (l > r.rlim_max))
227 r.rlim_cur = r.rlim_max;
228 else
229 r.rlim_cur = l;
230 if (setrlimit(what, &r) == -1)
231 bb_perror_msg_and_die("setrlimit");
232}
233
234int chpst_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
235int chpst_main(int argc UNUSED_PARAM, char **argv)
236{
237 struct bb_uidgid_t ugid;
238 char *set_user = set_user; /* for compiler */
239 char *env_dir = env_dir;
240 char *root;
241 char *nicestr;
242 unsigned limita;
243 unsigned limitc;
244 unsigned limitd;
245 unsigned limitf;
246 unsigned limitl;
247 unsigned limitm;
248 unsigned limito;
249 unsigned limitp;
250 unsigned limitr;
251 unsigned limits;
252 unsigned limitt;
253 unsigned opt;
254
255 if ((ENABLE_CHPST && applet_name[0] == 'c')
256 || (ENABLE_SOFTLIMIT && applet_name[1] == 'o')
257 ) {
258 // FIXME: can we live with int-sized limits?
259 // can we live with 40000 days?
260 // if yes -> getopt converts strings to numbers for us
261 opt_complementary = "-1:a+:c+:d+:f+:l+:m+:o+:p+:r+:s+:t+";
262 opt = getopt32(argv, "+a:c:d:f:l:m:o:p:r:s:t:u:U:e:"
263 IF_CHPST("/:n:vP012"),
264 &limita, &limitc, &limitd, &limitf, &limitl,
265 &limitm, &limito, &limitp, &limitr, &limits, &limitt,
266 &set_user, &set_user, &env_dir
267 IF_CHPST(, &root, &nicestr));
268 argv += optind;
269 if (opt & OPT_m) { // -m means -asld
270 limita = limits = limitl = limitd = limitm;
271 opt |= (OPT_s | OPT_l | OPT_a | OPT_d);
272 }
273 } else {
274 option_mask32 = opt = 0;
275 argv++;
276 if (!*argv)
277 bb_show_usage();
278 }
279
280 // envdir?
281 if (ENABLE_ENVDIR && applet_name[3] == 'd') {
282 env_dir = *argv++;
283 opt |= OPT_e;
284 }
285
286 // setuidgid?
287 if (ENABLE_SETUIDGID && applet_name[1] == 'e') {
288 set_user = *argv++;
289 opt |= OPT_u;
290 }
291
292 // envuidgid?
293 if (ENABLE_ENVUIDGID && applet_name[0] == 'e' && applet_name[3] == 'u') {
294 set_user = *argv++;
295 opt |= OPT_U;
296 }
297
298 // we must have PROG [ARGS]
299 if (!*argv)
300 bb_show_usage();
301
302 // set limits
303 if (opt & OPT_d) {
304#ifdef RLIMIT_DATA
305 limit(RLIMIT_DATA, limitd);
306#else
307 if (opt & OPT_v)
308 bb_error_msg("system does not support RLIMIT_%s",
309 "DATA");
310#endif
311 }
312 if (opt & OPT_s) {
313#ifdef RLIMIT_STACK
314 limit(RLIMIT_STACK, limits);
315#else
316 if (opt & OPT_v)
317 bb_error_msg("system does not support RLIMIT_%s",
318 "STACK");
319#endif
320 }
321 if (opt & OPT_l) {
322#ifdef RLIMIT_MEMLOCK
323 limit(RLIMIT_MEMLOCK, limitl);
324#else
325 if (opt & OPT_v)
326 bb_error_msg("system does not support RLIMIT_%s",
327 "MEMLOCK");
328#endif
329 }
330 if (opt & OPT_a) {
331#ifdef RLIMIT_VMEM
332 limit(RLIMIT_VMEM, limita);
333#else
334#ifdef RLIMIT_AS
335 limit(RLIMIT_AS, limita);
336#else
337 if (opt & OPT_v)
338 bb_error_msg("system does not support RLIMIT_%s",
339 "VMEM");
340#endif
341#endif
342 }
343 if (opt & OPT_o) {
344#ifdef RLIMIT_NOFILE
345 limit(RLIMIT_NOFILE, limito);
346#else
347#ifdef RLIMIT_OFILE
348 limit(RLIMIT_OFILE, limito);
349#else
350 if (opt & OPT_v)
351 bb_error_msg("system does not support RLIMIT_%s",
352 "NOFILE");
353#endif
354#endif
355 }
356 if (opt & OPT_p) {
357#ifdef RLIMIT_NPROC
358 limit(RLIMIT_NPROC, limitp);
359#else
360 if (opt & OPT_v)
361 bb_error_msg("system does not support RLIMIT_%s",
362 "NPROC");
363#endif
364 }
365 if (opt & OPT_f) {
366#ifdef RLIMIT_FSIZE
367 limit(RLIMIT_FSIZE, limitf);
368#else
369 if (opt & OPT_v)
370 bb_error_msg("system does not support RLIMIT_%s",
371 "FSIZE");
372#endif
373 }
374 if (opt & OPT_c) {
375#ifdef RLIMIT_CORE
376 limit(RLIMIT_CORE, limitc);
377#else
378 if (opt & OPT_v)
379 bb_error_msg("system does not support RLIMIT_%s",
380 "CORE");
381#endif
382 }
383 if (opt & OPT_r) {
384#ifdef RLIMIT_RSS
385 limit(RLIMIT_RSS, limitr);
386#else
387 if (opt & OPT_v)
388 bb_error_msg("system does not support RLIMIT_%s",
389 "RSS");
390#endif
391 }
392 if (opt & OPT_t) {
393#ifdef RLIMIT_CPU
394 limit(RLIMIT_CPU, limitt);
395#else
396 if (opt & OPT_v)
397 bb_error_msg("system does not support RLIMIT_%s",
398 "CPU");
399#endif
400 }
401
402 if (opt & OPT_P)
403 setsid();
404
405 if (opt & OPT_e)
406 edir(env_dir);
407
408 if (opt & (OPT_u|OPT_U))
409 xget_uidgid(&ugid, set_user);
410
411 // chrooted jail must have /etc/passwd if we move this after chroot.
412 // OTOH chroot fails for non-roots.
413 // Solution: cache uid/gid before chroot, apply uid/gid after.
414 if (opt & OPT_U) {
415 xsetenv("GID", utoa(ugid.gid));
416 xsetenv("UID", utoa(ugid.uid));
417 }
418
419 if (opt & OPT_root) {
420 xchroot(root);
421 }
422
423 if (opt & OPT_u) {
424 if (setgroups(1, &ugid.gid) == -1)
425 bb_perror_msg_and_die("setgroups");
426 xsetgid(ugid.gid);
427 xsetuid(ugid.uid);
428 }
429
430 if (opt & OPT_n) {
431 errno = 0;
432 if (nice(xatoi(nicestr)) == -1)
433 bb_perror_msg_and_die("nice");
434 }
435
436 if (opt & OPT_0)
437 close(STDIN_FILENO);
438 if (opt & OPT_1)
439 close(STDOUT_FILENO);
440 if (opt & OPT_2)
441 close(STDERR_FILENO);
442
443 BB_EXECVP_or_die(argv);
444}
445
generated by cgit at 2024-05-15 21:03:08 (GMT)