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1 | /* -*-c-*- |
2 | * |
372a98e2 |
3 | * $Id: exec.c,v 1.4 2001/02/03 20:30:03 mdw Exp $ |
48bb1f76 |
4 | * |
5 | * Source and target for executable programs |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of the `fw' port forwarder. |
13 | * |
14 | * `fw' is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU General Public License as published by |
16 | * the Free Software Foundation; either version 2 of the License, or |
17 | * (at your option) any later version. |
18 | * |
19 | * `fw' is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU General Public License |
25 | * along with `fw'; if not, write to the Free Software Foundation, |
26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
27 | */ |
28 | |
29 | /*----- Revision history --------------------------------------------------* |
30 | * |
31 | * $Log: exec.c,v $ |
372a98e2 |
32 | * Revision 1.4 2001/02/03 20:30:03 mdw |
33 | * Support re-reading config files on SIGHUP. |
34 | * |
e68b88bf |
35 | * Revision 1.3 2000/07/01 11:28:52 mdw |
36 | * Use new mLib selbuf features. |
37 | * |
28d2517c |
38 | * Revision 1.2 1999/10/22 22:46:17 mdw |
39 | * When a non-file endpoint is attached to a file, keep the file endpoint |
40 | * open until the nonfile is done. This stops socket sources from |
41 | * resetting their connection limits too early. |
42 | * |
48bb1f76 |
43 | * Revision 1.1 1999/07/26 23:33:32 mdw |
44 | * New sources and targets. |
45 | * |
46 | */ |
47 | |
48 | /*----- Header files ------------------------------------------------------*/ |
49 | |
50 | #include "config.h" |
51 | |
52 | #define _GNU_SOURCE |
53 | |
54 | #include <ctype.h> |
55 | #include <errno.h> |
56 | #include <signal.h> |
57 | #include <stdio.h> |
58 | #include <stdlib.h> |
59 | #include <string.h> |
60 | |
61 | #include <sys/types.h> |
62 | #include <sys/stat.h> |
63 | #include <unistd.h> |
64 | #include <fcntl.h> |
65 | #include <sys/wait.h> |
66 | |
67 | #ifdef HAVE_SETRLIMIT |
68 | # include <sys/resource.h> |
69 | #endif |
70 | |
71 | #ifndef DECL_ENVIRON |
72 | extern char **environ; |
73 | #endif |
74 | |
75 | #include <pwd.h> |
76 | #include <grp.h> |
77 | |
78 | #include <syslog.h> |
79 | |
80 | #include <mLib/alloc.h> |
81 | #include <mLib/dstr.h> |
82 | #include <mLib/env.h> |
83 | #include <mLib/fdflags.h> |
84 | #include <mLib/report.h> |
85 | #include <mLib/sel.h> |
86 | #include <mLib/selbuf.h> |
87 | #include <mLib/sig.h> |
88 | #include <mLib/sub.h> |
89 | #include <mLib/sym.h> |
90 | |
91 | #include "conf.h" |
92 | #include "endpt.h" |
93 | #include "exec.h" |
94 | #include "fattr.h" |
95 | #include "fw.h" |
96 | #include "reffd.h" |
97 | #include "scan.h" |
98 | #include "source.h" |
99 | #include "target.h" |
100 | |
101 | /*----- Data structures ---------------------------------------------------*/ |
102 | |
103 | /* --- Resource usage --- */ |
104 | |
105 | #ifdef HAVE_SETRLIMIT |
106 | |
107 | typedef struct xlimit { |
108 | #define R(r, n) struct rlimit n; |
109 | #include "rlimits.h" |
110 | } xlimit; |
111 | |
112 | #endif |
113 | |
114 | /* --- Environment variable modifications --- */ |
115 | |
116 | typedef struct xenv { |
117 | struct xenv *next; |
118 | unsigned act; |
119 | char *name; |
120 | char *value; |
121 | } xenv; |
122 | |
123 | #define XEA_SET 0u |
124 | #define XEA_CLEAR 1u |
125 | |
126 | /* --- Program options --- */ |
127 | |
128 | typedef struct xopts { |
129 | unsigned ref; |
130 | unsigned f; |
131 | const char *dir; |
132 | const char *root; |
133 | uid_t uid; |
134 | gid_t gid; |
135 | xenv *env; |
136 | xenv **etail; |
137 | #ifdef HAVE_SETRLIMIT |
138 | xlimit xl; |
139 | #endif |
140 | } xopts; |
141 | |
142 | #define XF_NOLOG 1u |
143 | |
144 | /* --- Executable program arguments --- */ |
145 | |
146 | typedef struct xargs { |
147 | unsigned ref; |
148 | char *file; |
149 | char *argv[1]; |
150 | } xargs; |
151 | |
152 | #define XARGS_SZ(n) (sizeof(xargs) + sizeof(char *) * (n)) |
153 | |
154 | /* --- Executable endpoints --- */ |
155 | |
156 | typedef struct xept { |
157 | endpt e; |
158 | struct xept *next, *prev; |
159 | pid_t kid; |
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160 | endpt *f; |
372a98e2 |
161 | char *desc; |
48bb1f76 |
162 | int st; |
163 | xargs *xa; |
164 | xopts *xo; |
165 | selbuf err; |
166 | } xept; |
167 | |
168 | #define XEF_CLOSE 16u |
169 | #define XEF_EXIT 32u |
170 | |
171 | /* --- Executable program data --- */ |
172 | |
173 | typedef struct xdata { |
174 | xargs *xa; |
175 | xopts *xo; |
176 | } xdata; |
177 | |
178 | /* --- Executable source block --- */ |
179 | |
180 | typedef struct xsource { |
181 | source s; |
182 | xdata x; |
183 | } xsource; |
184 | |
185 | /* --- Executable target block --- */ |
186 | |
187 | typedef struct xtarget { |
188 | target t; |
189 | xdata x; |
190 | } xtarget; |
191 | |
192 | /*----- Static variables --------------------------------------------------*/ |
193 | |
194 | static xopts exec_opts = { 1, 0, 0, 0, -1, -1, 0, &exec_opts.env }; |
195 | static xept *xept_list; |
196 | static sig xept_sig; |
197 | static sym_table env; |
198 | |
199 | /*----- Fiddling about with resource limits -------------------------------*/ |
200 | |
201 | #ifdef HAVE_SETRLIMIT |
202 | |
203 | /* --- Table mapping user-level names to OS interface bits --- */ |
204 | |
205 | typedef struct rlimit_ent { |
206 | const char *name; |
207 | const char *rname; |
208 | int r; |
209 | size_t off; |
210 | } rlimit_ent; |
211 | |
212 | static rlimit_ent rlimits[] = { |
213 | #define R(r, n) { #n, #r, r, offsetof(xlimit, n) }, |
214 | #include "rlimits.h" |
215 | { 0, 0, 0, 0 } |
216 | }; |
217 | |
218 | #define RLIMIT(xl, o) ((struct rlimit *)((char *)(xl) + (o))) |
219 | |
220 | /* --- @rlimit_get@ --- * |
221 | * |
222 | * Arguments: @xlimit *xl@ = pointer to limit structure |
223 | * |
224 | * Returns: --- |
225 | * |
226 | * Use: Initializes a limit structure from the current limits. |
227 | */ |
228 | |
229 | static void rlimit_get(xlimit *xl) |
230 | { |
231 | rlimit_ent *r; |
232 | |
233 | for (r = rlimits; r->name; r++) { |
234 | if (getrlimit(r->r, RLIMIT(xl, r->off))) { |
235 | moan("couldn't read %s: %s", r->rname, strerror(errno)); |
236 | _exit(1); |
237 | } |
238 | } |
239 | } |
240 | |
241 | /* --- @rlimit_set@ --- * |
242 | * |
243 | * Arguments: @xlimit *xl@ = pointer to limit structure |
244 | * |
245 | * Returns: --- |
246 | * |
247 | * Use: Sets resource limits from the supplied limits structure. |
248 | */ |
249 | |
250 | static void rlimit_set(xlimit *xl) |
251 | { |
252 | rlimit_ent *r; |
253 | |
254 | for (r = rlimits; r->name; r++) { |
255 | if (setrlimit(r->r, RLIMIT(xl, r->off))) { |
256 | moan("couldn't set %s: %s", r->rname, strerror(errno)); |
257 | _exit(1); |
258 | } |
259 | } |
260 | } |
261 | |
262 | /* --- @rlimit_option@ --- */ |
263 | |
264 | static int rlimit_option(xlimit *xl, scanner *sc) |
265 | { |
266 | CONF_BEGIN(sc, "rlimit", "resource limit") |
267 | enum { w_soft, w_hard, w_both } which = w_both; |
268 | rlimit_ent *chosen; |
269 | struct rlimit *rl; |
270 | long v; |
271 | |
272 | /* --- Find out which resource is being fiddled --- */ |
273 | |
274 | { |
275 | rlimit_ent *r; |
276 | |
277 | chosen = 0; |
278 | for (r = rlimits; r->name; r++) { |
279 | if (strncmp(sc->d.buf, r->name, sc->d.len) == 0) { |
280 | if (r->name[sc->d.len] == 0) { |
281 | chosen = r; |
282 | break; |
283 | } else if (chosen) |
284 | error(sc, "ambiguous resource limit name `%s'", sc->d.buf); |
285 | else if (CONF_QUAL) |
286 | chosen = r; |
287 | } |
288 | } |
289 | if (!chosen) |
290 | CONF_REJECT; |
291 | token(sc); |
292 | rl = RLIMIT(xl, chosen->off); |
293 | } |
294 | |
295 | /* --- Look for hard or soft restrictions --- */ |
296 | |
297 | { |
298 | int i; |
299 | if (sc->t == '.') |
300 | token(sc); |
301 | if (sc->t == CTOK_WORD) { |
302 | if ((i = conf_enum(sc, "soft,hard", |
303 | ENUM_ABBREV | ENUM_NONE, "limit type")) != -1) |
304 | which = i; |
305 | } |
306 | } |
307 | |
308 | /* --- Now read the new value --- */ |
309 | |
310 | if (sc->t == '=') |
311 | token(sc); |
312 | if (sc->t != CTOK_WORD) |
313 | error(sc, "parse error, expected limit value"); |
314 | |
315 | if (conf_enum(sc, "unlimited,infinity", |
316 | ENUM_ABBREV | ENUM_NONE, "limit value") > -1) |
317 | v = RLIM_INFINITY; |
318 | else { |
319 | char *p; |
320 | |
321 | v = strtol(sc->d.buf, &p, 0); |
322 | if (p == sc->d.buf) |
323 | error(sc, "parse error, invalid limit value `%s'", sc->d.buf); |
324 | switch (tolower((unsigned char)*p)) { |
325 | case 0: break; |
326 | case 'b': v *= 512; break; |
327 | case 'g': v *= 1024; |
328 | case 'm': v *= 1024; |
329 | case 'k': v *= 1024; break; |
330 | default: error(sc, "parse error, invalid limit scale `%c'", *p); |
331 | } |
332 | token(sc); |
333 | } |
334 | |
335 | /* --- Store the limit value away --- */ |
336 | |
337 | switch (which) { |
338 | case w_both: |
339 | rl->rlim_cur = v; |
340 | rl->rlim_max = v; |
341 | break; |
342 | case w_soft: |
343 | if (v > rl->rlim_max) |
344 | error(sc, "soft limit %l exceeds hard limit %l for %s", |
345 | v, rl->rlim_max, chosen->rname); |
346 | rl->rlim_cur = v; |
347 | break; |
348 | case w_hard: |
349 | rl->rlim_max = v; |
350 | if (rl->rlim_cur > v) |
351 | rl->rlim_cur = v; |
352 | break; |
353 | } |
354 | |
355 | CONF_ACCEPT; |
356 | CONF_END; |
357 | } |
358 | |
359 | #endif |
360 | |
361 | /*----- Environment fiddling ----------------------------------------------*/ |
362 | |
363 | /* --- @xenv_option@ --- * |
364 | * |
365 | * Arguments: @xopts *xo@ = pointer to options block |
366 | * @scanner *sc@ = pointer to scanner |
367 | * |
368 | * Returns: Nonzero if claimed |
369 | * |
370 | * Use: Parses environment variable assignments. |
371 | */ |
372 | |
373 | static int xenv_option(xopts *xo, scanner *sc) |
374 | { |
375 | CONF_BEGIN(sc, "env", "environment") |
376 | xenv *xe; |
377 | |
378 | /* --- Unset a variable --- */ |
379 | |
380 | if (strcmp(sc->d.buf, "unset") == 0) { |
381 | token(sc); |
382 | if (sc->t != CTOK_WORD) |
383 | error(sc, "parse error, expected environment variable name"); |
384 | xe = CREATE(xenv); |
385 | xe->name = xstrdup(sc->d.buf); |
386 | xe->value = 0; |
387 | xe->act = XEA_SET; |
388 | token(sc); |
389 | goto link; |
390 | } |
391 | |
392 | /* --- Clear the entire environment --- */ |
393 | |
394 | if (strcmp(sc->d.buf, "clear") == 0) { |
395 | token(sc); |
396 | xe = CREATE(xenv); |
397 | xe->act = XEA_CLEAR; |
398 | goto link; |
399 | } |
400 | |
401 | /* --- Allow `set' to be omitted if there's a prefix --- */ |
402 | |
403 | if (strcmp(sc->d.buf, "set") == 0) |
404 | token(sc); |
405 | else if (!CONF_QUAL) |
406 | CONF_REJECT; |
407 | |
408 | /* --- Set a variable --- */ |
409 | |
410 | if (sc->t != CTOK_WORD) |
411 | error(sc, "parse error, expected environment variable name"); |
412 | xe = CREATE(xenv); |
413 | xe->name = xstrdup(sc->d.buf); |
414 | token(sc); |
415 | if (sc->t == '=') |
416 | token(sc); |
417 | if (sc->t != CTOK_WORD) |
418 | error(sc, "parse error, expected environment variable value"); |
419 | xe->value = xstrdup(sc->d.buf); |
420 | xe->act = XEA_SET; |
421 | token(sc); |
422 | goto link; |
423 | |
424 | link: |
425 | xe->next = 0; |
426 | *xo->etail = xe; |
427 | xo->etail = &xe->next; |
428 | CONF_ACCEPT; |
429 | |
430 | /* --- Nothing else to try --- */ |
431 | |
432 | CONF_END; |
433 | } |
434 | |
435 | /* --- @xenv_apply@ --- * |
436 | * |
437 | * Arguments: @xenv *xe@ = pointer to a variable change list |
438 | * |
439 | * Returns: --- |
440 | * |
441 | * Use: Modifies the environment (in @env@) according to the list. |
442 | */ |
443 | |
444 | static void xenv_apply(xenv *xe) |
445 | { |
446 | while (xe) { |
447 | switch (xe->act) { |
448 | case XEA_SET: |
449 | env_put(&env, xe->name, xe->value); |
450 | break; |
451 | case XEA_CLEAR: |
452 | env_destroy(&env); |
453 | sym_create(&env); |
454 | break; |
455 | } |
456 | xe = xe->next; |
457 | } |
458 | } |
459 | |
460 | /* --- @xenv_destroy@ --- * |
461 | * |
462 | * Arguments: @xenv *xe@ = pointer to a variable change list |
463 | * |
464 | * Returns: --- |
465 | * |
466 | * Use: Frees the memory used by an environment variable change list. |
467 | */ |
468 | |
469 | static void xenv_destroy(xenv *xe) |
470 | { |
471 | while (xe) { |
472 | xenv *xxe = xe; |
473 | xe = xe->next; |
474 | free(xxe->name); |
475 | if (xxe->value) |
476 | free(xxe->value); |
477 | DESTROY(xxe); |
478 | } |
479 | } |
480 | |
481 | /*----- Miscellaneous good things -----------------------------------------*/ |
482 | |
483 | /* --- @x_tidy@ --- * |
484 | * |
485 | * Arguments: @xargs *xa@ = pointer to an arguments block |
486 | * @xopts *xo@ = pointer to an options block |
487 | * |
488 | * Returns: --- |
489 | * |
490 | * Use: Releases a reference to argument and options blocks. |
491 | */ |
492 | |
493 | static void x_tidy(xargs *xa, xopts *xo) |
494 | { |
495 | xa->ref--; |
496 | if (!xa->ref) |
497 | free(xa); |
498 | |
499 | xo->ref--; |
500 | if (!xo->ref) { |
501 | xenv_destroy(xo->env); |
502 | DESTROY(xo); |
503 | } |
504 | } |
505 | |
506 | /*----- Executable endpoints ----------------------------------------------*/ |
507 | |
508 | /* --- @attach@ --- */ |
509 | |
510 | static void xept_error(char */*p*/, void */*v*/); |
511 | |
512 | static void xept_attach(endpt *e, reffd *in, reffd *out) |
513 | { |
514 | xept *xe = (xept *)e; |
515 | pid_t kid; |
516 | int fd[2]; |
517 | |
518 | /* --- Make a pipe for standard error --- */ |
519 | |
520 | if (pipe(fd)) { |
521 | fw_log(-1, "[%s] couldn't create pipe: %s", xe->desc, strerror(errno)); |
522 | return; |
523 | } |
524 | fdflags(fd[0], O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC); |
525 | |
526 | /* --- Fork a child, and handle an error if there was one --- */ |
527 | |
528 | if ((kid = fork()) == -1) { |
529 | fw_log(-1, "[%s] couldn't fork: %s", xe->desc, strerror(errno)); |
530 | close(fd[0]); |
531 | close(fd[1]); |
532 | return; |
533 | } |
534 | |
535 | /* --- Do the child thing --- */ |
536 | |
537 | if (kid == 0) { |
538 | xopts *xo = xe->xo; |
539 | |
540 | /* --- Fiddle with the file descriptors --- * |
541 | * |
542 | * Attach the other endpoint's descriptors to standard input and output. |
543 | * Attach my pipe to standard error. Mark everything as blocking and |
544 | * not-to-be-closed-on-exec at this end. |
545 | */ |
546 | |
547 | close(fd[0]); |
548 | if (dup2(in->fd, STDIN_FILENO) < 0 || |
549 | dup2(out->fd, STDOUT_FILENO) < 0 || |
550 | dup2(fd[1], STDERR_FILENO) < 0) { |
551 | moan("couldn't manipulate file descriptors: %s", strerror(errno)); |
552 | _exit(1); |
553 | } |
554 | |
555 | if (in->fd > 2) |
556 | close(in->fd); |
557 | if (out->fd > 2) |
558 | close(out->fd); |
559 | |
560 | fdflags(STDIN_FILENO, O_NONBLOCK, 0, FD_CLOEXEC, 0); |
561 | fdflags(STDOUT_FILENO, O_NONBLOCK, 0, FD_CLOEXEC, 0); |
562 | fdflags(STDERR_FILENO, O_NONBLOCK, 0, FD_CLOEXEC, 0); |
563 | |
564 | /* --- First of all set the @chroot@ prison --- */ |
565 | |
566 | if (xo->root && chroot(xo->root)) { |
567 | moan("couldn't set `%s' as filesystem root: %s", |
568 | xo->root, strerror(errno)); |
569 | _exit(1); |
570 | } |
571 | |
572 | /* --- Now set the current directory --- */ |
573 | |
574 | if (xo->dir ? chdir(xo->dir) : xo->root ? chdir("/") : 0) { |
575 | moan("couldn't set `%s' as current directory: %s", |
576 | xo->dir ? xo->dir : "/", strerror(errno)); |
577 | _exit(1); |
578 | } |
579 | |
580 | /* --- Set the resource limits --- */ |
581 | |
582 | #ifdef HAVE_SETRLIMIT |
583 | rlimit_set(&xo->xl); |
584 | #endif |
585 | |
586 | /* --- Set group id --- */ |
587 | |
588 | if (xo->gid != -1) { |
589 | if (setgid(xo->gid)) { |
590 | moan("couldn't set gid %i: %s", xo->gid, strerror(errno)); |
591 | _exit(1); |
592 | } |
593 | #ifdef HAVE_SETGROUPS |
594 | if (setgroups(1, &xo->gid)) |
595 | moan("warning: couldn't set group list to %i: %s", xo->gid, |
596 | strerror(errno)); |
597 | #endif |
598 | } |
599 | |
600 | /* --- Set uid --- */ |
601 | |
602 | if (xo->uid != -1) { |
603 | if (setuid(xo->uid)) { |
604 | moan("couldn't set uid %i: %s", xo->uid, strerror(errno)); |
605 | _exit(1); |
606 | } |
607 | } |
608 | |
609 | /* --- Play with signal dispositions --- */ |
610 | |
611 | signal(SIGPIPE, SIG_DFL); |
612 | |
613 | /* --- Fiddle with the environment --- */ |
614 | |
615 | xenv_apply(exec_opts.env); |
616 | xenv_apply(xe->xo->env); |
617 | environ = env_export(&env); |
618 | |
619 | /* --- Run the program --- */ |
620 | |
621 | execvp(xe->xa->file, xe->xa->argv); |
622 | moan("couldn't execute `%s': %s", xe->xa->file, strerror(errno)); |
623 | _exit(127); |
624 | } |
625 | |
626 | /* --- The child's done; see to the parent --- */ |
627 | |
628 | xe->kid = kid; |
629 | selbuf_init(&xe->err, sel, fd[0], xept_error, xe); |
630 | close(fd[1]); |
631 | xe->next = xept_list; |
632 | xe->prev = 0; |
633 | if (xept_list) |
634 | xept_list->prev = xe; |
635 | xept_list = xe; |
636 | if (!(xe->xo->f & XF_NOLOG)) |
637 | fw_log(-1, "[%s] started with pid %i", xe->desc, kid); |
638 | fw_inc(); |
639 | return; |
640 | } |
641 | |
28d2517c |
642 | /* --- @xept_file@ --- */ |
643 | |
644 | static void xept_file(endpt *e, endpt *f) |
645 | { |
646 | xept *xe = (xept *)e; |
647 | xe->f = f; |
648 | } |
649 | |
48bb1f76 |
650 | /* --- @xept_close@ --- */ |
651 | |
652 | static void xept_close(endpt *e) |
653 | { |
654 | xept *xe = (xept *)e; |
655 | if (xe->kid == -1) { |
28d2517c |
656 | if (xe->f) |
657 | xe->f->ops->close(xe->f); |
48bb1f76 |
658 | x_tidy(xe->xa, xe->xo); |
659 | DESTROY(xe); |
660 | fw_dec(); |
661 | } |
662 | } |
663 | |
664 | /* --- @xept_destroy@ --- */ |
665 | |
666 | static void xept_destroy(xept *xe) |
667 | { |
668 | /* --- First emit the news about the process --- */ |
669 | |
670 | if (xe->xo->f & XF_NOLOG) |
671 | /* Nothin' doin' */; |
672 | else if (WIFEXITED(xe->st)) { |
673 | if (WEXITSTATUS(xe->st) == 0) |
674 | fw_log(-1, "[%s] pid %i exited successfully", xe->desc, xe->kid); |
675 | else { |
676 | fw_log(-1, "[%s] pid %i failed: status %i", |
677 | xe->desc, xe->kid, WEXITSTATUS(xe->st)); |
678 | } |
679 | } else if (WIFSIGNALED(xe->st)) { |
680 | const char *s; |
681 | #ifdef HAVE_STRSIGNAL |
682 | s = strsignal(WTERMSIG(xe->st)); |
683 | #elif HAVE__SYS_SIGLIST |
684 | s = _sys_siglist[WTERMSIG(xe->st)]; |
685 | #else |
686 | char buf[32]; |
687 | sprintf(buf, "signal %i", WTERMSIG(xe->st)); |
688 | s = buf; |
689 | #endif |
690 | fw_log(-1, "[%s] pid %i failed: %s", xe->desc, xe->kid, s); |
691 | } else |
692 | fw_log(-1, "[%s] pid %i failed: unrecognized status", xe->desc, xe->kid); |
693 | |
694 | /* --- Free up the parent-side resources --- */ |
695 | |
696 | if (xe->next) |
697 | xe->next->prev = xe->prev; |
698 | if (xe->prev) |
699 | xe->prev->next = xe->next; |
700 | else |
701 | xept_list = xe->next; |
702 | |
372a98e2 |
703 | free(xe->desc); |
28d2517c |
704 | if (xe->f) |
705 | xe->f->ops->close(xe->f); |
48bb1f76 |
706 | x_tidy(xe->xa, xe->xo); |
707 | fw_dec(); |
708 | DESTROY(xe); |
709 | } |
710 | |
711 | /* --- @xept_chld@ --- * |
712 | * |
713 | * Arguments: @int n@ = signal number |
714 | * @void *p@ = uninteresting pointer |
715 | * |
716 | * Returns: --- |
717 | * |
718 | * Use: Deals with child death situations. |
719 | */ |
720 | |
721 | static void xept_chld(int n, void *p) |
722 | { |
723 | pid_t kid; |
724 | int st; |
725 | |
726 | while ((kid = waitpid(-1, &st, WNOHANG)) > 0) { |
727 | xept *xe = xept_list; |
728 | while (xe) { |
729 | xept *xxe = xe; |
730 | xe = xe->next; |
731 | if (kid == xxe->kid) { |
732 | xxe->st = st; |
733 | xxe->e.f |= XEF_EXIT; |
734 | if (xxe->e.f & XEF_CLOSE) |
735 | xept_destroy(xxe); |
736 | break; |
737 | } |
738 | } |
739 | } |
740 | } |
741 | |
742 | /* --- @xept_error@ --- * |
743 | * |
744 | * Arguments: @char *p@ = pointer to string read from stderr |
745 | * @void *v@ = pointer to by endpoint |
746 | * |
747 | * Returns: --- |
748 | * |
749 | * Use: Handles error reports from a child process. |
750 | */ |
751 | |
752 | static void xept_error(char *p, void *v) |
753 | { |
754 | xept *xe = v; |
755 | if (p) |
756 | fw_log(-1, "[%s] pid %i: %s", xe->desc, xe->kid, p); |
757 | else { |
48bb1f76 |
758 | close(xe->err.reader.fd); |
e68b88bf |
759 | selbuf_destroy(&xe->err); |
48bb1f76 |
760 | xe->e.f |= XEF_CLOSE; |
761 | if (xe->e.f & XEF_EXIT) |
762 | xept_destroy(xe); |
763 | } |
764 | } |
765 | |
766 | /* --- Endpoint operations --- */ |
767 | |
28d2517c |
768 | static endpt_ops xept_ops = { xept_attach, xept_file, 0, xept_close }; |
48bb1f76 |
769 | |
770 | /*----- General operations on sources and targets -------------------------*/ |
771 | |
772 | /* --- @exec_init@ --- * |
773 | * |
774 | * Arguments: --- |
775 | * |
776 | * Returns: --- |
777 | * |
778 | * Use: Initializes the executable problem source and target. |
779 | */ |
780 | |
781 | void exec_init(void) |
782 | { |
783 | rlimit_get(&exec_opts.xl); |
784 | sig_add(&xept_sig, SIGCHLD, xept_chld, 0); |
785 | sym_create(&env); |
786 | env_import(&env, environ); |
787 | } |
788 | |
789 | /* --- @exec_option@ --- */ |
790 | |
791 | static int exec_option(xdata *x, scanner *sc) |
792 | { |
793 | xopts *xo = x ? x->xo : &exec_opts; |
794 | |
795 | CONF_BEGIN(sc, "exec", "executable"); |
796 | |
797 | /* --- Logging settings --- */ |
798 | |
799 | if (strcmp(sc->d.buf, "logging") == 0 || |
800 | strcmp(sc->d.buf, "log") == 0) { |
801 | token(sc); |
802 | if (sc->t == '=') |
803 | token(sc); |
804 | if (conf_enum(sc, "no,yes", ENUM_ABBREV, "logging status")) |
805 | xo->f &= ~XF_NOLOG; |
806 | else |
807 | xo->f |= XF_NOLOG; |
808 | CONF_ACCEPT; |
809 | } |
810 | |
811 | /* --- Current directory setting --- * |
812 | * |
813 | * Lots of possibilities to guard against possible brainoes. |
814 | */ |
815 | |
816 | if (strcmp(sc->d.buf, "dir") == 0 || |
817 | strcmp(sc->d.buf, "cd") == 0 || |
818 | strcmp(sc->d.buf, "chdir") == 0 || |
819 | strcmp(sc->d.buf, "cwd") == 0) { |
820 | dstr d = DSTR_INIT; |
821 | token(sc); |
822 | if (sc->t == '=') |
823 | token(sc); |
824 | conf_name(sc, '/', &d); |
825 | xo->dir = xstrdup(d.buf); |
826 | dstr_destroy(&d); |
827 | CONF_ACCEPT; |
828 | } |
829 | |
830 | /* --- Set a chroot prison --- */ |
831 | |
832 | if (strcmp(sc->d.buf, "root") == 0 || |
833 | strcmp(sc->d.buf, "chroot") == 0) { |
834 | dstr d = DSTR_INIT; |
835 | token(sc); |
836 | if (sc->t == '=') |
837 | token(sc); |
838 | conf_name(sc, '/', &d); |
839 | xo->root = xstrdup(d.buf); |
840 | dstr_destroy(&d); |
841 | CONF_ACCEPT; |
842 | } |
843 | |
844 | /* --- Set the target user id --- */ |
845 | |
846 | if (strcmp(sc->d.buf, "uid") == 0 || |
847 | strcmp(sc->d.buf, "user") == 0) { |
848 | token(sc); |
849 | if (sc->t == '=') |
850 | token(sc); |
851 | if (sc->t != CTOK_WORD) |
852 | error(sc, "parse error, expected user name or uid"); |
853 | if (isdigit((unsigned char)*sc->d.buf)) |
854 | xo->uid = atoi(sc->d.buf); |
855 | else { |
856 | struct passwd *pw = getpwnam(sc->d.buf); |
857 | if (!pw) |
858 | error(sc, "unknown user name `%s'", sc->d.buf); |
859 | xo->uid = pw->pw_uid; |
860 | } |
861 | token(sc); |
862 | CONF_ACCEPT; |
863 | } |
864 | |
865 | /* --- Set the target group id --- */ |
866 | |
867 | if (strcmp(sc->d.buf, "gid") == 0 || |
868 | strcmp(sc->d.buf, "group") == 0) { |
869 | token(sc); |
870 | if (sc->t == '=') |
871 | token(sc); |
872 | if (sc->t != CTOK_WORD) |
873 | error(sc, "parse error, expected group name or gid"); |
874 | if (isdigit((unsigned char)*sc->d.buf)) |
875 | xo->gid = atoi(sc->d.buf); |
876 | else { |
877 | struct group *gr = getgrnam(sc->d.buf); |
878 | if (!gr) |
879 | error(sc, "unknown user name `%s'", sc->d.buf); |
880 | xo->gid = gr->gr_gid; |
881 | } |
882 | token(sc); |
883 | CONF_ACCEPT; |
884 | } |
885 | |
886 | /* --- Now try resource limit settings --- */ |
887 | |
888 | if (rlimit_option(&xo->xl, sc)) |
889 | CONF_ACCEPT; |
890 | |
891 | /* --- And then environment settings --- */ |
892 | |
893 | if (xenv_option(xo, sc)) |
894 | CONF_ACCEPT; |
895 | |
896 | /* --- Nothing found --- */ |
897 | |
898 | CONF_END; |
899 | } |
900 | |
901 | /* --- @exec_desc@ --- */ |
902 | |
903 | static void exec_desc(xdata *x, dstr *d) |
904 | { |
905 | char **p; |
906 | char sep = '['; |
907 | dstr_puts(d, "exec "); |
908 | if (strcmp(x->xa->file, x->xa->argv[0]) != 0) { |
909 | dstr_puts(d, x->xa->file); |
910 | dstr_putc(d, ' '); |
911 | } |
912 | for (p = x->xa->argv; *p; p++) { |
913 | dstr_putc(d, sep); |
914 | dstr_puts(d, *p); |
915 | sep = ' '; |
916 | } |
917 | dstr_putc(d, ']'); |
918 | dstr_putz(d); |
919 | } |
920 | |
921 | /* --- @exec_read@ --- */ |
922 | |
923 | static void exec_read(xdata *x, scanner *sc) |
924 | { |
925 | size_t base = 0; |
926 | dstr d = DSTR_INIT; |
927 | xargs *xa; |
928 | |
929 | /* --- Read the first word --- * |
930 | * |
931 | * This is either a shell command or the actual program to run. |
932 | */ |
933 | |
934 | if (sc->t == CTOK_WORD) { |
935 | dstr_putd(&d, &sc->d); d.len++; |
936 | base = d.len; |
937 | token(sc); |
938 | } |
939 | |
940 | /* --- See if there's a list of arguments --- * |
941 | * |
942 | * If not, then the thing I saw was a shell command, so build the proper |
943 | * arguments for that. |
944 | */ |
945 | |
946 | if (sc->t != '[') { |
947 | char *p; |
948 | if (!base) |
949 | error(sc, "parse error, expected shell command or argument list"); |
950 | xa = xmalloc(XARGS_SZ(3) + 8 + 3 + d.len); |
951 | p = (char *)(xa->argv + 4); |
952 | xa->ref = 1; |
953 | xa->file = p; |
954 | xa->argv[0] = p; memcpy(p, "/bin/sh", 8); p += 8; |
955 | xa->argv[1] = p; memcpy(p, "-c", 3); p += 3; |
956 | xa->argv[2] = p; memcpy(p, d.buf, d.len); p += d.len; |
957 | xa->argv[3] = 0; |
958 | } |
959 | |
960 | /* --- Snarf in a list of arguments --- */ |
961 | |
962 | else { |
963 | int argc = 0; |
964 | char *p, *q; |
965 | char **v; |
966 | |
967 | /* --- Strip off the leading `[' --- */ |
968 | |
969 | token(sc); |
970 | |
971 | /* --- Read a sequence of arguments --- */ |
972 | |
973 | while (sc->t == CTOK_WORD) { |
974 | dstr_putd(&d, &sc->d); d.len++; |
975 | token(sc); |
976 | argc++; |
977 | } |
978 | |
979 | /* --- Expect the closing `]' --- */ |
980 | |
981 | if (sc->t != ']') |
982 | error(sc, "parse error, missing `]'"); |
983 | token(sc); |
984 | |
985 | /* --- If there are no arguments, whinge --- */ |
986 | |
987 | if (!argc) |
988 | error(sc, "must specify at least one argument"); |
989 | |
990 | /* --- Allocate a lump of memory for the array --- */ |
991 | |
992 | xa = xmalloc(XARGS_SZ(argc) + d.len); |
993 | xa->ref = 1; |
994 | v = xa->argv; |
995 | p = (char *)(v + argc + 1); |
996 | memcpy(p, d.buf, d.len); |
997 | q = p + d.len; |
998 | xa->file = p; |
999 | p += base; |
1000 | |
1001 | /* --- Start dumping addresses into the @argv@ array --- */ |
1002 | |
1003 | for (;;) { |
1004 | *v++ = p; |
1005 | while (*p++ && p < q) |
1006 | ; |
1007 | if (p >= q) |
1008 | break; |
1009 | } |
1010 | *v++ = 0; |
1011 | } |
1012 | |
1013 | /* --- Do some other setting up --- */ |
1014 | |
1015 | dstr_destroy(&d); |
1016 | x->xa = xa; |
1017 | x->xo = CREATE(xopts); |
1018 | *x->xo = exec_opts; |
1019 | x->xo->ref = 1; |
1020 | return; |
1021 | } |
1022 | |
1023 | /* --- @exec_endpt@ --- */ |
1024 | |
1025 | static endpt *exec_endpt(xdata *x, const char *desc) |
1026 | { |
1027 | xept *xe = CREATE(xept); |
1028 | xe->e.ops = &xept_ops; |
1029 | xe->e.other = 0; |
1030 | xe->e.t = 0; |
1031 | xe->e.f = 0; |
1032 | xe->xa = x->xa; xe->xa->ref++; |
1033 | xe->xo = x->xo; xe->xo->ref++; |
1034 | xe->kid = -1; |
28d2517c |
1035 | xe->f = 0; |
372a98e2 |
1036 | xe->desc = xstrdup(desc); |
48bb1f76 |
1037 | return (&xe->e); |
1038 | } |
1039 | |
1040 | /* --- @exec_destroy@ --- */ |
1041 | |
1042 | static void exec_destroy(xdata *x) |
1043 | { |
1044 | x_tidy(x->xa, x->xo); |
1045 | } |
1046 | |
1047 | /*----- Source definition -------------------------------------------------*/ |
1048 | |
1049 | /* --- @option@ --- */ |
1050 | |
1051 | static int xsource_option(source *s, scanner *sc) |
1052 | { |
1053 | xsource *xs = (xsource *)s; |
1054 | return (exec_option(xs ? &xs->x : 0, sc)); |
1055 | } |
1056 | |
1057 | /* --- @read@ --- */ |
1058 | |
1059 | static source *xsource_read(scanner *sc) |
1060 | { |
1061 | xsource *xs; |
1062 | |
1063 | if (!conf_prefix(sc, "exec")) |
1064 | return (0); |
1065 | xs = CREATE(xsource); |
1066 | xs->s.ops = &xsource_ops; |
1067 | xs->s.desc = 0; |
1068 | exec_read(&xs->x, sc); |
1069 | return (&xs->s); |
1070 | } |
1071 | |
1072 | /* --- @attach@ --- */ |
1073 | |
1074 | static void xsource_destroy(source */*s*/); |
1075 | |
1076 | static void xsource_attach(source *s, scanner *sc, target *t) |
1077 | { |
1078 | xsource *xs = (xsource *)s; |
1079 | endpt *e, *ee; |
1080 | |
1081 | /* --- Set up the source description string --- */ |
1082 | |
1083 | { |
1084 | dstr d = DSTR_INIT; |
1085 | exec_desc(&xs->x, &d); |
1086 | dstr_puts(&d, " -> "); |
1087 | dstr_puts(&d, t->desc); |
1088 | xs->s.desc = xstrdup(d.buf); |
1089 | dstr_destroy(&d); |
1090 | } |
1091 | |
1092 | /* --- Create the endpoints --- */ |
1093 | |
1094 | if ((ee = t->ops->create(t, xs->s.desc)) == 0) |
1095 | goto tidy; |
1096 | if ((e = exec_endpt(&xs->x, xs->s.desc)) == 0) { |
1097 | ee->ops->close(ee); |
1098 | goto tidy; |
1099 | } |
1100 | endpt_join(e, ee); |
1101 | |
1102 | /* --- Dispose of source and target --- */ |
1103 | |
1104 | tidy: |
1105 | t->ops->destroy(t); |
1106 | xsource_destroy(&xs->s); |
1107 | } |
1108 | |
1109 | /* --- @destroy@ --- */ |
1110 | |
1111 | static void xsource_destroy(source *s) |
1112 | { |
1113 | xsource *xs = (xsource *)s; |
372a98e2 |
1114 | free(xs->s.desc); |
48bb1f76 |
1115 | exec_destroy(&xs->x); |
1116 | DESTROY(xs); |
1117 | } |
1118 | |
1119 | /* --- Executable source operations --- */ |
1120 | |
1121 | source_ops xsource_ops = { |
1122 | "exec", |
1123 | xsource_option, xsource_read, xsource_attach, xsource_destroy |
1124 | }; |
1125 | |
1126 | /*----- Exec target description -------------------------------------------*/ |
1127 | |
1128 | /* --- @option@ --- */ |
1129 | |
1130 | static int xtarget_option(target *t, scanner *sc) |
1131 | { |
1132 | xtarget *xt = (xtarget *)t; |
1133 | return (exec_option(xt ? &xt->x : 0, sc)); |
1134 | } |
1135 | |
1136 | /* --- @read@ --- */ |
1137 | |
1138 | static target *xtarget_read(scanner *sc) |
1139 | { |
1140 | xtarget *xt; |
1141 | dstr d = DSTR_INIT; |
1142 | |
1143 | if (!conf_prefix(sc, "exec")) |
1144 | return (0); |
1145 | xt = CREATE(xtarget); |
1146 | xt->t.ops = &xtarget_ops; |
1147 | exec_read(&xt->x, sc); |
1148 | exec_desc(&xt->x, &d); |
1149 | xt->t.desc = xstrdup(d.buf); |
1150 | dstr_destroy(&d); |
1151 | return (&xt->t); |
1152 | } |
1153 | |
1154 | /* --- @create@ --- */ |
1155 | |
1156 | static endpt *xtarget_create(target *t, const char *desc) |
1157 | { |
1158 | xtarget *xt = (xtarget *)t; |
1159 | endpt *e = exec_endpt(&xt->x, desc); |
1160 | return (e); |
1161 | } |
1162 | |
1163 | /* --- @destroy@ --- */ |
1164 | |
1165 | static void xtarget_destroy(target *t) |
1166 | { |
1167 | xtarget *xt = (xtarget *)t; |
372a98e2 |
1168 | free(xt->t.desc); |
48bb1f76 |
1169 | exec_destroy(&xt->x); |
1170 | DESTROY(xt); |
1171 | } |
1172 | |
1173 | /* --- Exec target operations --- */ |
1174 | |
1175 | target_ops xtarget_ops = { |
1176 | "exec", |
1177 | xtarget_option, xtarget_read, xtarget_create, xtarget_destroy |
1178 | }; |
1179 | |
1180 | /*----- That's all, folks -------------------------------------------------*/ |