48bb1f76 |
1 | /* -*-c-*- |
2 | * |
f00786b9 |
3 | * $Id: exec.c,v 1.5 2002/01/13 14:49:03 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 $ |
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32 | * Revision 1.5 2002/01/13 14:49:03 mdw |
33 | * Track @lbuf@ changes in mLib. |
34 | * |
372a98e2 |
35 | * Revision 1.4 2001/02/03 20:30:03 mdw |
36 | * Support re-reading config files on SIGHUP. |
37 | * |
e68b88bf |
38 | * Revision 1.3 2000/07/01 11:28:52 mdw |
39 | * Use new mLib selbuf features. |
40 | * |
28d2517c |
41 | * Revision 1.2 1999/10/22 22:46:17 mdw |
42 | * When a non-file endpoint is attached to a file, keep the file endpoint |
43 | * open until the nonfile is done. This stops socket sources from |
44 | * resetting their connection limits too early. |
45 | * |
48bb1f76 |
46 | * Revision 1.1 1999/07/26 23:33:32 mdw |
47 | * New sources and targets. |
48 | * |
49 | */ |
50 | |
51 | /*----- Header files ------------------------------------------------------*/ |
52 | |
53 | #include "config.h" |
54 | |
55 | #define _GNU_SOURCE |
56 | |
57 | #include <ctype.h> |
58 | #include <errno.h> |
59 | #include <signal.h> |
60 | #include <stdio.h> |
61 | #include <stdlib.h> |
62 | #include <string.h> |
63 | |
64 | #include <sys/types.h> |
65 | #include <sys/stat.h> |
66 | #include <unistd.h> |
67 | #include <fcntl.h> |
68 | #include <sys/wait.h> |
69 | |
70 | #ifdef HAVE_SETRLIMIT |
71 | # include <sys/resource.h> |
72 | #endif |
73 | |
74 | #ifndef DECL_ENVIRON |
75 | extern char **environ; |
76 | #endif |
77 | |
78 | #include <pwd.h> |
79 | #include <grp.h> |
80 | |
81 | #include <syslog.h> |
82 | |
83 | #include <mLib/alloc.h> |
84 | #include <mLib/dstr.h> |
85 | #include <mLib/env.h> |
86 | #include <mLib/fdflags.h> |
87 | #include <mLib/report.h> |
88 | #include <mLib/sel.h> |
89 | #include <mLib/selbuf.h> |
90 | #include <mLib/sig.h> |
91 | #include <mLib/sub.h> |
92 | #include <mLib/sym.h> |
93 | |
94 | #include "conf.h" |
95 | #include "endpt.h" |
96 | #include "exec.h" |
97 | #include "fattr.h" |
98 | #include "fw.h" |
99 | #include "reffd.h" |
100 | #include "scan.h" |
101 | #include "source.h" |
102 | #include "target.h" |
103 | |
104 | /*----- Data structures ---------------------------------------------------*/ |
105 | |
106 | /* --- Resource usage --- */ |
107 | |
108 | #ifdef HAVE_SETRLIMIT |
109 | |
110 | typedef struct xlimit { |
111 | #define R(r, n) struct rlimit n; |
112 | #include "rlimits.h" |
113 | } xlimit; |
114 | |
115 | #endif |
116 | |
117 | /* --- Environment variable modifications --- */ |
118 | |
119 | typedef struct xenv { |
120 | struct xenv *next; |
121 | unsigned act; |
122 | char *name; |
123 | char *value; |
124 | } xenv; |
125 | |
126 | #define XEA_SET 0u |
127 | #define XEA_CLEAR 1u |
128 | |
129 | /* --- Program options --- */ |
130 | |
131 | typedef struct xopts { |
132 | unsigned ref; |
133 | unsigned f; |
134 | const char *dir; |
135 | const char *root; |
136 | uid_t uid; |
137 | gid_t gid; |
138 | xenv *env; |
139 | xenv **etail; |
140 | #ifdef HAVE_SETRLIMIT |
141 | xlimit xl; |
142 | #endif |
143 | } xopts; |
144 | |
145 | #define XF_NOLOG 1u |
146 | |
147 | /* --- Executable program arguments --- */ |
148 | |
149 | typedef struct xargs { |
150 | unsigned ref; |
151 | char *file; |
152 | char *argv[1]; |
153 | } xargs; |
154 | |
155 | #define XARGS_SZ(n) (sizeof(xargs) + sizeof(char *) * (n)) |
156 | |
157 | /* --- Executable endpoints --- */ |
158 | |
159 | typedef struct xept { |
160 | endpt e; |
161 | struct xept *next, *prev; |
162 | pid_t kid; |
28d2517c |
163 | endpt *f; |
372a98e2 |
164 | char *desc; |
48bb1f76 |
165 | int st; |
166 | xargs *xa; |
167 | xopts *xo; |
168 | selbuf err; |
169 | } xept; |
170 | |
171 | #define XEF_CLOSE 16u |
172 | #define XEF_EXIT 32u |
173 | |
174 | /* --- Executable program data --- */ |
175 | |
176 | typedef struct xdata { |
177 | xargs *xa; |
178 | xopts *xo; |
179 | } xdata; |
180 | |
181 | /* --- Executable source block --- */ |
182 | |
183 | typedef struct xsource { |
184 | source s; |
185 | xdata x; |
186 | } xsource; |
187 | |
188 | /* --- Executable target block --- */ |
189 | |
190 | typedef struct xtarget { |
191 | target t; |
192 | xdata x; |
193 | } xtarget; |
194 | |
195 | /*----- Static variables --------------------------------------------------*/ |
196 | |
197 | static xopts exec_opts = { 1, 0, 0, 0, -1, -1, 0, &exec_opts.env }; |
198 | static xept *xept_list; |
199 | static sig xept_sig; |
200 | static sym_table env; |
201 | |
202 | /*----- Fiddling about with resource limits -------------------------------*/ |
203 | |
204 | #ifdef HAVE_SETRLIMIT |
205 | |
206 | /* --- Table mapping user-level names to OS interface bits --- */ |
207 | |
208 | typedef struct rlimit_ent { |
209 | const char *name; |
210 | const char *rname; |
211 | int r; |
212 | size_t off; |
213 | } rlimit_ent; |
214 | |
215 | static rlimit_ent rlimits[] = { |
216 | #define R(r, n) { #n, #r, r, offsetof(xlimit, n) }, |
217 | #include "rlimits.h" |
218 | { 0, 0, 0, 0 } |
219 | }; |
220 | |
221 | #define RLIMIT(xl, o) ((struct rlimit *)((char *)(xl) + (o))) |
222 | |
223 | /* --- @rlimit_get@ --- * |
224 | * |
225 | * Arguments: @xlimit *xl@ = pointer to limit structure |
226 | * |
227 | * Returns: --- |
228 | * |
229 | * Use: Initializes a limit structure from the current limits. |
230 | */ |
231 | |
232 | static void rlimit_get(xlimit *xl) |
233 | { |
234 | rlimit_ent *r; |
235 | |
236 | for (r = rlimits; r->name; r++) { |
237 | if (getrlimit(r->r, RLIMIT(xl, r->off))) { |
238 | moan("couldn't read %s: %s", r->rname, strerror(errno)); |
239 | _exit(1); |
240 | } |
241 | } |
242 | } |
243 | |
244 | /* --- @rlimit_set@ --- * |
245 | * |
246 | * Arguments: @xlimit *xl@ = pointer to limit structure |
247 | * |
248 | * Returns: --- |
249 | * |
250 | * Use: Sets resource limits from the supplied limits structure. |
251 | */ |
252 | |
253 | static void rlimit_set(xlimit *xl) |
254 | { |
255 | rlimit_ent *r; |
256 | |
257 | for (r = rlimits; r->name; r++) { |
258 | if (setrlimit(r->r, RLIMIT(xl, r->off))) { |
259 | moan("couldn't set %s: %s", r->rname, strerror(errno)); |
260 | _exit(1); |
261 | } |
262 | } |
263 | } |
264 | |
265 | /* --- @rlimit_option@ --- */ |
266 | |
267 | static int rlimit_option(xlimit *xl, scanner *sc) |
268 | { |
269 | CONF_BEGIN(sc, "rlimit", "resource limit") |
270 | enum { w_soft, w_hard, w_both } which = w_both; |
271 | rlimit_ent *chosen; |
272 | struct rlimit *rl; |
273 | long v; |
274 | |
275 | /* --- Find out which resource is being fiddled --- */ |
276 | |
277 | { |
278 | rlimit_ent *r; |
279 | |
280 | chosen = 0; |
281 | for (r = rlimits; r->name; r++) { |
282 | if (strncmp(sc->d.buf, r->name, sc->d.len) == 0) { |
283 | if (r->name[sc->d.len] == 0) { |
284 | chosen = r; |
285 | break; |
286 | } else if (chosen) |
287 | error(sc, "ambiguous resource limit name `%s'", sc->d.buf); |
288 | else if (CONF_QUAL) |
289 | chosen = r; |
290 | } |
291 | } |
292 | if (!chosen) |
293 | CONF_REJECT; |
294 | token(sc); |
295 | rl = RLIMIT(xl, chosen->off); |
296 | } |
297 | |
298 | /* --- Look for hard or soft restrictions --- */ |
299 | |
300 | { |
301 | int i; |
302 | if (sc->t == '.') |
303 | token(sc); |
304 | if (sc->t == CTOK_WORD) { |
305 | if ((i = conf_enum(sc, "soft,hard", |
306 | ENUM_ABBREV | ENUM_NONE, "limit type")) != -1) |
307 | which = i; |
308 | } |
309 | } |
310 | |
311 | /* --- Now read the new value --- */ |
312 | |
313 | if (sc->t == '=') |
314 | token(sc); |
315 | if (sc->t != CTOK_WORD) |
316 | error(sc, "parse error, expected limit value"); |
317 | |
318 | if (conf_enum(sc, "unlimited,infinity", |
319 | ENUM_ABBREV | ENUM_NONE, "limit value") > -1) |
320 | v = RLIM_INFINITY; |
321 | else { |
322 | char *p; |
323 | |
324 | v = strtol(sc->d.buf, &p, 0); |
325 | if (p == sc->d.buf) |
326 | error(sc, "parse error, invalid limit value `%s'", sc->d.buf); |
327 | switch (tolower((unsigned char)*p)) { |
328 | case 0: break; |
329 | case 'b': v *= 512; break; |
330 | case 'g': v *= 1024; |
331 | case 'm': v *= 1024; |
332 | case 'k': v *= 1024; break; |
333 | default: error(sc, "parse error, invalid limit scale `%c'", *p); |
334 | } |
335 | token(sc); |
336 | } |
337 | |
338 | /* --- Store the limit value away --- */ |
339 | |
340 | switch (which) { |
341 | case w_both: |
342 | rl->rlim_cur = v; |
343 | rl->rlim_max = v; |
344 | break; |
345 | case w_soft: |
346 | if (v > rl->rlim_max) |
347 | error(sc, "soft limit %l exceeds hard limit %l for %s", |
348 | v, rl->rlim_max, chosen->rname); |
349 | rl->rlim_cur = v; |
350 | break; |
351 | case w_hard: |
352 | rl->rlim_max = v; |
353 | if (rl->rlim_cur > v) |
354 | rl->rlim_cur = v; |
355 | break; |
356 | } |
357 | |
358 | CONF_ACCEPT; |
359 | CONF_END; |
360 | } |
361 | |
362 | #endif |
363 | |
364 | /*----- Environment fiddling ----------------------------------------------*/ |
365 | |
366 | /* --- @xenv_option@ --- * |
367 | * |
368 | * Arguments: @xopts *xo@ = pointer to options block |
369 | * @scanner *sc@ = pointer to scanner |
370 | * |
371 | * Returns: Nonzero if claimed |
372 | * |
373 | * Use: Parses environment variable assignments. |
374 | */ |
375 | |
376 | static int xenv_option(xopts *xo, scanner *sc) |
377 | { |
378 | CONF_BEGIN(sc, "env", "environment") |
379 | xenv *xe; |
380 | |
381 | /* --- Unset a variable --- */ |
382 | |
383 | if (strcmp(sc->d.buf, "unset") == 0) { |
384 | token(sc); |
385 | if (sc->t != CTOK_WORD) |
386 | error(sc, "parse error, expected environment variable name"); |
387 | xe = CREATE(xenv); |
388 | xe->name = xstrdup(sc->d.buf); |
389 | xe->value = 0; |
390 | xe->act = XEA_SET; |
391 | token(sc); |
392 | goto link; |
393 | } |
394 | |
395 | /* --- Clear the entire environment --- */ |
396 | |
397 | if (strcmp(sc->d.buf, "clear") == 0) { |
398 | token(sc); |
399 | xe = CREATE(xenv); |
400 | xe->act = XEA_CLEAR; |
401 | goto link; |
402 | } |
403 | |
404 | /* --- Allow `set' to be omitted if there's a prefix --- */ |
405 | |
406 | if (strcmp(sc->d.buf, "set") == 0) |
407 | token(sc); |
408 | else if (!CONF_QUAL) |
409 | CONF_REJECT; |
410 | |
411 | /* --- Set a variable --- */ |
412 | |
413 | if (sc->t != CTOK_WORD) |
414 | error(sc, "parse error, expected environment variable name"); |
415 | xe = CREATE(xenv); |
416 | xe->name = xstrdup(sc->d.buf); |
417 | token(sc); |
418 | if (sc->t == '=') |
419 | token(sc); |
420 | if (sc->t != CTOK_WORD) |
421 | error(sc, "parse error, expected environment variable value"); |
422 | xe->value = xstrdup(sc->d.buf); |
423 | xe->act = XEA_SET; |
424 | token(sc); |
425 | goto link; |
426 | |
427 | link: |
428 | xe->next = 0; |
429 | *xo->etail = xe; |
430 | xo->etail = &xe->next; |
431 | CONF_ACCEPT; |
432 | |
433 | /* --- Nothing else to try --- */ |
434 | |
435 | CONF_END; |
436 | } |
437 | |
438 | /* --- @xenv_apply@ --- * |
439 | * |
440 | * Arguments: @xenv *xe@ = pointer to a variable change list |
441 | * |
442 | * Returns: --- |
443 | * |
444 | * Use: Modifies the environment (in @env@) according to the list. |
445 | */ |
446 | |
447 | static void xenv_apply(xenv *xe) |
448 | { |
449 | while (xe) { |
450 | switch (xe->act) { |
451 | case XEA_SET: |
452 | env_put(&env, xe->name, xe->value); |
453 | break; |
454 | case XEA_CLEAR: |
455 | env_destroy(&env); |
456 | sym_create(&env); |
457 | break; |
458 | } |
459 | xe = xe->next; |
460 | } |
461 | } |
462 | |
463 | /* --- @xenv_destroy@ --- * |
464 | * |
465 | * Arguments: @xenv *xe@ = pointer to a variable change list |
466 | * |
467 | * Returns: --- |
468 | * |
469 | * Use: Frees the memory used by an environment variable change list. |
470 | */ |
471 | |
472 | static void xenv_destroy(xenv *xe) |
473 | { |
474 | while (xe) { |
475 | xenv *xxe = xe; |
476 | xe = xe->next; |
477 | free(xxe->name); |
478 | if (xxe->value) |
479 | free(xxe->value); |
480 | DESTROY(xxe); |
481 | } |
482 | } |
483 | |
484 | /*----- Miscellaneous good things -----------------------------------------*/ |
485 | |
486 | /* --- @x_tidy@ --- * |
487 | * |
488 | * Arguments: @xargs *xa@ = pointer to an arguments block |
489 | * @xopts *xo@ = pointer to an options block |
490 | * |
491 | * Returns: --- |
492 | * |
493 | * Use: Releases a reference to argument and options blocks. |
494 | */ |
495 | |
496 | static void x_tidy(xargs *xa, xopts *xo) |
497 | { |
498 | xa->ref--; |
499 | if (!xa->ref) |
500 | free(xa); |
501 | |
502 | xo->ref--; |
503 | if (!xo->ref) { |
504 | xenv_destroy(xo->env); |
505 | DESTROY(xo); |
506 | } |
507 | } |
508 | |
509 | /*----- Executable endpoints ----------------------------------------------*/ |
510 | |
511 | /* --- @attach@ --- */ |
512 | |
f00786b9 |
513 | static void xept_error(char */*p*/, size_t /*len*/, void */*v*/); |
48bb1f76 |
514 | |
515 | static void xept_attach(endpt *e, reffd *in, reffd *out) |
516 | { |
517 | xept *xe = (xept *)e; |
518 | pid_t kid; |
519 | int fd[2]; |
520 | |
521 | /* --- Make a pipe for standard error --- */ |
522 | |
523 | if (pipe(fd)) { |
524 | fw_log(-1, "[%s] couldn't create pipe: %s", xe->desc, strerror(errno)); |
525 | return; |
526 | } |
527 | fdflags(fd[0], O_NONBLOCK, O_NONBLOCK, FD_CLOEXEC, FD_CLOEXEC); |
528 | |
529 | /* --- Fork a child, and handle an error if there was one --- */ |
530 | |
531 | if ((kid = fork()) == -1) { |
532 | fw_log(-1, "[%s] couldn't fork: %s", xe->desc, strerror(errno)); |
533 | close(fd[0]); |
534 | close(fd[1]); |
535 | return; |
536 | } |
537 | |
538 | /* --- Do the child thing --- */ |
539 | |
540 | if (kid == 0) { |
541 | xopts *xo = xe->xo; |
542 | |
543 | /* --- Fiddle with the file descriptors --- * |
544 | * |
545 | * Attach the other endpoint's descriptors to standard input and output. |
546 | * Attach my pipe to standard error. Mark everything as blocking and |
547 | * not-to-be-closed-on-exec at this end. |
548 | */ |
549 | |
550 | close(fd[0]); |
551 | if (dup2(in->fd, STDIN_FILENO) < 0 || |
552 | dup2(out->fd, STDOUT_FILENO) < 0 || |
553 | dup2(fd[1], STDERR_FILENO) < 0) { |
554 | moan("couldn't manipulate file descriptors: %s", strerror(errno)); |
555 | _exit(1); |
556 | } |
557 | |
558 | if (in->fd > 2) |
559 | close(in->fd); |
560 | if (out->fd > 2) |
561 | close(out->fd); |
562 | |
563 | fdflags(STDIN_FILENO, O_NONBLOCK, 0, FD_CLOEXEC, 0); |
564 | fdflags(STDOUT_FILENO, O_NONBLOCK, 0, FD_CLOEXEC, 0); |
565 | fdflags(STDERR_FILENO, O_NONBLOCK, 0, FD_CLOEXEC, 0); |
566 | |
567 | /* --- First of all set the @chroot@ prison --- */ |
568 | |
569 | if (xo->root && chroot(xo->root)) { |
570 | moan("couldn't set `%s' as filesystem root: %s", |
571 | xo->root, strerror(errno)); |
572 | _exit(1); |
573 | } |
574 | |
575 | /* --- Now set the current directory --- */ |
576 | |
577 | if (xo->dir ? chdir(xo->dir) : xo->root ? chdir("/") : 0) { |
578 | moan("couldn't set `%s' as current directory: %s", |
579 | xo->dir ? xo->dir : "/", strerror(errno)); |
580 | _exit(1); |
581 | } |
582 | |
583 | /* --- Set the resource limits --- */ |
584 | |
585 | #ifdef HAVE_SETRLIMIT |
586 | rlimit_set(&xo->xl); |
587 | #endif |
588 | |
589 | /* --- Set group id --- */ |
590 | |
591 | if (xo->gid != -1) { |
592 | if (setgid(xo->gid)) { |
593 | moan("couldn't set gid %i: %s", xo->gid, strerror(errno)); |
594 | _exit(1); |
595 | } |
596 | #ifdef HAVE_SETGROUPS |
597 | if (setgroups(1, &xo->gid)) |
598 | moan("warning: couldn't set group list to %i: %s", xo->gid, |
599 | strerror(errno)); |
600 | #endif |
601 | } |
602 | |
603 | /* --- Set uid --- */ |
604 | |
605 | if (xo->uid != -1) { |
606 | if (setuid(xo->uid)) { |
607 | moan("couldn't set uid %i: %s", xo->uid, strerror(errno)); |
608 | _exit(1); |
609 | } |
610 | } |
611 | |
612 | /* --- Play with signal dispositions --- */ |
613 | |
614 | signal(SIGPIPE, SIG_DFL); |
615 | |
616 | /* --- Fiddle with the environment --- */ |
617 | |
618 | xenv_apply(exec_opts.env); |
619 | xenv_apply(xe->xo->env); |
620 | environ = env_export(&env); |
621 | |
622 | /* --- Run the program --- */ |
623 | |
624 | execvp(xe->xa->file, xe->xa->argv); |
625 | moan("couldn't execute `%s': %s", xe->xa->file, strerror(errno)); |
626 | _exit(127); |
627 | } |
628 | |
629 | /* --- The child's done; see to the parent --- */ |
630 | |
631 | xe->kid = kid; |
632 | selbuf_init(&xe->err, sel, fd[0], xept_error, xe); |
633 | close(fd[1]); |
634 | xe->next = xept_list; |
635 | xe->prev = 0; |
636 | if (xept_list) |
637 | xept_list->prev = xe; |
638 | xept_list = xe; |
639 | if (!(xe->xo->f & XF_NOLOG)) |
640 | fw_log(-1, "[%s] started with pid %i", xe->desc, kid); |
641 | fw_inc(); |
642 | return; |
643 | } |
644 | |
28d2517c |
645 | /* --- @xept_file@ --- */ |
646 | |
647 | static void xept_file(endpt *e, endpt *f) |
648 | { |
649 | xept *xe = (xept *)e; |
650 | xe->f = f; |
651 | } |
652 | |
48bb1f76 |
653 | /* --- @xept_close@ --- */ |
654 | |
655 | static void xept_close(endpt *e) |
656 | { |
657 | xept *xe = (xept *)e; |
658 | if (xe->kid == -1) { |
28d2517c |
659 | if (xe->f) |
660 | xe->f->ops->close(xe->f); |
48bb1f76 |
661 | x_tidy(xe->xa, xe->xo); |
662 | DESTROY(xe); |
663 | fw_dec(); |
664 | } |
665 | } |
666 | |
667 | /* --- @xept_destroy@ --- */ |
668 | |
669 | static void xept_destroy(xept *xe) |
670 | { |
671 | /* --- First emit the news about the process --- */ |
672 | |
673 | if (xe->xo->f & XF_NOLOG) |
674 | /* Nothin' doin' */; |
675 | else if (WIFEXITED(xe->st)) { |
676 | if (WEXITSTATUS(xe->st) == 0) |
677 | fw_log(-1, "[%s] pid %i exited successfully", xe->desc, xe->kid); |
678 | else { |
679 | fw_log(-1, "[%s] pid %i failed: status %i", |
680 | xe->desc, xe->kid, WEXITSTATUS(xe->st)); |
681 | } |
682 | } else if (WIFSIGNALED(xe->st)) { |
683 | const char *s; |
684 | #ifdef HAVE_STRSIGNAL |
685 | s = strsignal(WTERMSIG(xe->st)); |
686 | #elif HAVE__SYS_SIGLIST |
687 | s = _sys_siglist[WTERMSIG(xe->st)]; |
688 | #else |
689 | char buf[32]; |
690 | sprintf(buf, "signal %i", WTERMSIG(xe->st)); |
691 | s = buf; |
692 | #endif |
693 | fw_log(-1, "[%s] pid %i failed: %s", xe->desc, xe->kid, s); |
694 | } else |
695 | fw_log(-1, "[%s] pid %i failed: unrecognized status", xe->desc, xe->kid); |
696 | |
697 | /* --- Free up the parent-side resources --- */ |
698 | |
699 | if (xe->next) |
700 | xe->next->prev = xe->prev; |
701 | if (xe->prev) |
702 | xe->prev->next = xe->next; |
703 | else |
704 | xept_list = xe->next; |
705 | |
372a98e2 |
706 | free(xe->desc); |
28d2517c |
707 | if (xe->f) |
708 | xe->f->ops->close(xe->f); |
48bb1f76 |
709 | x_tidy(xe->xa, xe->xo); |
710 | fw_dec(); |
711 | DESTROY(xe); |
712 | } |
713 | |
714 | /* --- @xept_chld@ --- * |
715 | * |
716 | * Arguments: @int n@ = signal number |
717 | * @void *p@ = uninteresting pointer |
718 | * |
719 | * Returns: --- |
720 | * |
721 | * Use: Deals with child death situations. |
722 | */ |
723 | |
724 | static void xept_chld(int n, void *p) |
725 | { |
726 | pid_t kid; |
727 | int st; |
728 | |
729 | while ((kid = waitpid(-1, &st, WNOHANG)) > 0) { |
730 | xept *xe = xept_list; |
731 | while (xe) { |
732 | xept *xxe = xe; |
733 | xe = xe->next; |
734 | if (kid == xxe->kid) { |
735 | xxe->st = st; |
736 | xxe->e.f |= XEF_EXIT; |
737 | if (xxe->e.f & XEF_CLOSE) |
738 | xept_destroy(xxe); |
739 | break; |
740 | } |
741 | } |
742 | } |
743 | } |
744 | |
745 | /* --- @xept_error@ --- * |
746 | * |
747 | * Arguments: @char *p@ = pointer to string read from stderr |
f00786b9 |
748 | * @size_t len@ = length of the string |
48bb1f76 |
749 | * @void *v@ = pointer to by endpoint |
750 | * |
751 | * Returns: --- |
752 | * |
753 | * Use: Handles error reports from a child process. |
754 | */ |
755 | |
f00786b9 |
756 | static void xept_error(char *p, size_t len, void *v) |
48bb1f76 |
757 | { |
758 | xept *xe = v; |
759 | if (p) |
760 | fw_log(-1, "[%s] pid %i: %s", xe->desc, xe->kid, p); |
761 | else { |
48bb1f76 |
762 | close(xe->err.reader.fd); |
e68b88bf |
763 | selbuf_destroy(&xe->err); |
48bb1f76 |
764 | xe->e.f |= XEF_CLOSE; |
765 | if (xe->e.f & XEF_EXIT) |
766 | xept_destroy(xe); |
767 | } |
768 | } |
769 | |
770 | /* --- Endpoint operations --- */ |
771 | |
28d2517c |
772 | static endpt_ops xept_ops = { xept_attach, xept_file, 0, xept_close }; |
48bb1f76 |
773 | |
774 | /*----- General operations on sources and targets -------------------------*/ |
775 | |
776 | /* --- @exec_init@ --- * |
777 | * |
778 | * Arguments: --- |
779 | * |
780 | * Returns: --- |
781 | * |
782 | * Use: Initializes the executable problem source and target. |
783 | */ |
784 | |
785 | void exec_init(void) |
786 | { |
787 | rlimit_get(&exec_opts.xl); |
788 | sig_add(&xept_sig, SIGCHLD, xept_chld, 0); |
789 | sym_create(&env); |
790 | env_import(&env, environ); |
791 | } |
792 | |
793 | /* --- @exec_option@ --- */ |
794 | |
795 | static int exec_option(xdata *x, scanner *sc) |
796 | { |
797 | xopts *xo = x ? x->xo : &exec_opts; |
798 | |
799 | CONF_BEGIN(sc, "exec", "executable"); |
800 | |
801 | /* --- Logging settings --- */ |
802 | |
803 | if (strcmp(sc->d.buf, "logging") == 0 || |
804 | strcmp(sc->d.buf, "log") == 0) { |
805 | token(sc); |
806 | if (sc->t == '=') |
807 | token(sc); |
808 | if (conf_enum(sc, "no,yes", ENUM_ABBREV, "logging status")) |
809 | xo->f &= ~XF_NOLOG; |
810 | else |
811 | xo->f |= XF_NOLOG; |
812 | CONF_ACCEPT; |
813 | } |
814 | |
815 | /* --- Current directory setting --- * |
816 | * |
817 | * Lots of possibilities to guard against possible brainoes. |
818 | */ |
819 | |
820 | if (strcmp(sc->d.buf, "dir") == 0 || |
821 | strcmp(sc->d.buf, "cd") == 0 || |
822 | strcmp(sc->d.buf, "chdir") == 0 || |
823 | strcmp(sc->d.buf, "cwd") == 0) { |
824 | dstr d = DSTR_INIT; |
825 | token(sc); |
826 | if (sc->t == '=') |
827 | token(sc); |
828 | conf_name(sc, '/', &d); |
829 | xo->dir = xstrdup(d.buf); |
830 | dstr_destroy(&d); |
831 | CONF_ACCEPT; |
832 | } |
833 | |
834 | /* --- Set a chroot prison --- */ |
835 | |
836 | if (strcmp(sc->d.buf, "root") == 0 || |
837 | strcmp(sc->d.buf, "chroot") == 0) { |
838 | dstr d = DSTR_INIT; |
839 | token(sc); |
840 | if (sc->t == '=') |
841 | token(sc); |
842 | conf_name(sc, '/', &d); |
843 | xo->root = xstrdup(d.buf); |
844 | dstr_destroy(&d); |
845 | CONF_ACCEPT; |
846 | } |
847 | |
848 | /* --- Set the target user id --- */ |
849 | |
850 | if (strcmp(sc->d.buf, "uid") == 0 || |
851 | strcmp(sc->d.buf, "user") == 0) { |
852 | token(sc); |
853 | if (sc->t == '=') |
854 | token(sc); |
855 | if (sc->t != CTOK_WORD) |
856 | error(sc, "parse error, expected user name or uid"); |
857 | if (isdigit((unsigned char)*sc->d.buf)) |
858 | xo->uid = atoi(sc->d.buf); |
859 | else { |
860 | struct passwd *pw = getpwnam(sc->d.buf); |
861 | if (!pw) |
862 | error(sc, "unknown user name `%s'", sc->d.buf); |
863 | xo->uid = pw->pw_uid; |
864 | } |
865 | token(sc); |
866 | CONF_ACCEPT; |
867 | } |
868 | |
869 | /* --- Set the target group id --- */ |
870 | |
871 | if (strcmp(sc->d.buf, "gid") == 0 || |
872 | strcmp(sc->d.buf, "group") == 0) { |
873 | token(sc); |
874 | if (sc->t == '=') |
875 | token(sc); |
876 | if (sc->t != CTOK_WORD) |
877 | error(sc, "parse error, expected group name or gid"); |
878 | if (isdigit((unsigned char)*sc->d.buf)) |
879 | xo->gid = atoi(sc->d.buf); |
880 | else { |
881 | struct group *gr = getgrnam(sc->d.buf); |
882 | if (!gr) |
883 | error(sc, "unknown user name `%s'", sc->d.buf); |
884 | xo->gid = gr->gr_gid; |
885 | } |
886 | token(sc); |
887 | CONF_ACCEPT; |
888 | } |
889 | |
890 | /* --- Now try resource limit settings --- */ |
891 | |
892 | if (rlimit_option(&xo->xl, sc)) |
893 | CONF_ACCEPT; |
894 | |
895 | /* --- And then environment settings --- */ |
896 | |
897 | if (xenv_option(xo, sc)) |
898 | CONF_ACCEPT; |
899 | |
900 | /* --- Nothing found --- */ |
901 | |
902 | CONF_END; |
903 | } |
904 | |
905 | /* --- @exec_desc@ --- */ |
906 | |
907 | static void exec_desc(xdata *x, dstr *d) |
908 | { |
909 | char **p; |
910 | char sep = '['; |
911 | dstr_puts(d, "exec "); |
912 | if (strcmp(x->xa->file, x->xa->argv[0]) != 0) { |
913 | dstr_puts(d, x->xa->file); |
914 | dstr_putc(d, ' '); |
915 | } |
916 | for (p = x->xa->argv; *p; p++) { |
917 | dstr_putc(d, sep); |
918 | dstr_puts(d, *p); |
919 | sep = ' '; |
920 | } |
921 | dstr_putc(d, ']'); |
922 | dstr_putz(d); |
923 | } |
924 | |
925 | /* --- @exec_read@ --- */ |
926 | |
927 | static void exec_read(xdata *x, scanner *sc) |
928 | { |
929 | size_t base = 0; |
930 | dstr d = DSTR_INIT; |
931 | xargs *xa; |
932 | |
933 | /* --- Read the first word --- * |
934 | * |
935 | * This is either a shell command or the actual program to run. |
936 | */ |
937 | |
938 | if (sc->t == CTOK_WORD) { |
939 | dstr_putd(&d, &sc->d); d.len++; |
940 | base = d.len; |
941 | token(sc); |
942 | } |
943 | |
944 | /* --- See if there's a list of arguments --- * |
945 | * |
946 | * If not, then the thing I saw was a shell command, so build the proper |
947 | * arguments for that. |
948 | */ |
949 | |
950 | if (sc->t != '[') { |
951 | char *p; |
952 | if (!base) |
953 | error(sc, "parse error, expected shell command or argument list"); |
954 | xa = xmalloc(XARGS_SZ(3) + 8 + 3 + d.len); |
955 | p = (char *)(xa->argv + 4); |
956 | xa->ref = 1; |
957 | xa->file = p; |
958 | xa->argv[0] = p; memcpy(p, "/bin/sh", 8); p += 8; |
959 | xa->argv[1] = p; memcpy(p, "-c", 3); p += 3; |
960 | xa->argv[2] = p; memcpy(p, d.buf, d.len); p += d.len; |
961 | xa->argv[3] = 0; |
962 | } |
963 | |
964 | /* --- Snarf in a list of arguments --- */ |
965 | |
966 | else { |
967 | int argc = 0; |
968 | char *p, *q; |
969 | char **v; |
970 | |
971 | /* --- Strip off the leading `[' --- */ |
972 | |
973 | token(sc); |
974 | |
975 | /* --- Read a sequence of arguments --- */ |
976 | |
977 | while (sc->t == CTOK_WORD) { |
978 | dstr_putd(&d, &sc->d); d.len++; |
979 | token(sc); |
980 | argc++; |
981 | } |
982 | |
983 | /* --- Expect the closing `]' --- */ |
984 | |
985 | if (sc->t != ']') |
986 | error(sc, "parse error, missing `]'"); |
987 | token(sc); |
988 | |
989 | /* --- If there are no arguments, whinge --- */ |
990 | |
991 | if (!argc) |
992 | error(sc, "must specify at least one argument"); |
993 | |
994 | /* --- Allocate a lump of memory for the array --- */ |
995 | |
996 | xa = xmalloc(XARGS_SZ(argc) + d.len); |
997 | xa->ref = 1; |
998 | v = xa->argv; |
999 | p = (char *)(v + argc + 1); |
1000 | memcpy(p, d.buf, d.len); |
1001 | q = p + d.len; |
1002 | xa->file = p; |
1003 | p += base; |
1004 | |
1005 | /* --- Start dumping addresses into the @argv@ array --- */ |
1006 | |
1007 | for (;;) { |
1008 | *v++ = p; |
1009 | while (*p++ && p < q) |
1010 | ; |
1011 | if (p >= q) |
1012 | break; |
1013 | } |
1014 | *v++ = 0; |
1015 | } |
1016 | |
1017 | /* --- Do some other setting up --- */ |
1018 | |
1019 | dstr_destroy(&d); |
1020 | x->xa = xa; |
1021 | x->xo = CREATE(xopts); |
1022 | *x->xo = exec_opts; |
1023 | x->xo->ref = 1; |
1024 | return; |
1025 | } |
1026 | |
1027 | /* --- @exec_endpt@ --- */ |
1028 | |
1029 | static endpt *exec_endpt(xdata *x, const char *desc) |
1030 | { |
1031 | xept *xe = CREATE(xept); |
1032 | xe->e.ops = &xept_ops; |
1033 | xe->e.other = 0; |
1034 | xe->e.t = 0; |
1035 | xe->e.f = 0; |
1036 | xe->xa = x->xa; xe->xa->ref++; |
1037 | xe->xo = x->xo; xe->xo->ref++; |
1038 | xe->kid = -1; |
28d2517c |
1039 | xe->f = 0; |
372a98e2 |
1040 | xe->desc = xstrdup(desc); |
48bb1f76 |
1041 | return (&xe->e); |
1042 | } |
1043 | |
1044 | /* --- @exec_destroy@ --- */ |
1045 | |
1046 | static void exec_destroy(xdata *x) |
1047 | { |
1048 | x_tidy(x->xa, x->xo); |
1049 | } |
1050 | |
1051 | /*----- Source definition -------------------------------------------------*/ |
1052 | |
1053 | /* --- @option@ --- */ |
1054 | |
1055 | static int xsource_option(source *s, scanner *sc) |
1056 | { |
1057 | xsource *xs = (xsource *)s; |
1058 | return (exec_option(xs ? &xs->x : 0, sc)); |
1059 | } |
1060 | |
1061 | /* --- @read@ --- */ |
1062 | |
1063 | static source *xsource_read(scanner *sc) |
1064 | { |
1065 | xsource *xs; |
1066 | |
1067 | if (!conf_prefix(sc, "exec")) |
1068 | return (0); |
1069 | xs = CREATE(xsource); |
1070 | xs->s.ops = &xsource_ops; |
1071 | xs->s.desc = 0; |
1072 | exec_read(&xs->x, sc); |
1073 | return (&xs->s); |
1074 | } |
1075 | |
1076 | /* --- @attach@ --- */ |
1077 | |
1078 | static void xsource_destroy(source */*s*/); |
1079 | |
1080 | static void xsource_attach(source *s, scanner *sc, target *t) |
1081 | { |
1082 | xsource *xs = (xsource *)s; |
1083 | endpt *e, *ee; |
1084 | |
1085 | /* --- Set up the source description string --- */ |
1086 | |
1087 | { |
1088 | dstr d = DSTR_INIT; |
1089 | exec_desc(&xs->x, &d); |
1090 | dstr_puts(&d, " -> "); |
1091 | dstr_puts(&d, t->desc); |
1092 | xs->s.desc = xstrdup(d.buf); |
1093 | dstr_destroy(&d); |
1094 | } |
1095 | |
1096 | /* --- Create the endpoints --- */ |
1097 | |
1098 | if ((ee = t->ops->create(t, xs->s.desc)) == 0) |
1099 | goto tidy; |
1100 | if ((e = exec_endpt(&xs->x, xs->s.desc)) == 0) { |
1101 | ee->ops->close(ee); |
1102 | goto tidy; |
1103 | } |
1104 | endpt_join(e, ee); |
1105 | |
1106 | /* --- Dispose of source and target --- */ |
1107 | |
1108 | tidy: |
1109 | t->ops->destroy(t); |
1110 | xsource_destroy(&xs->s); |
1111 | } |
1112 | |
1113 | /* --- @destroy@ --- */ |
1114 | |
1115 | static void xsource_destroy(source *s) |
1116 | { |
1117 | xsource *xs = (xsource *)s; |
372a98e2 |
1118 | free(xs->s.desc); |
48bb1f76 |
1119 | exec_destroy(&xs->x); |
1120 | DESTROY(xs); |
1121 | } |
1122 | |
1123 | /* --- Executable source operations --- */ |
1124 | |
1125 | source_ops xsource_ops = { |
1126 | "exec", |
1127 | xsource_option, xsource_read, xsource_attach, xsource_destroy |
1128 | }; |
1129 | |
1130 | /*----- Exec target description -------------------------------------------*/ |
1131 | |
1132 | /* --- @option@ --- */ |
1133 | |
1134 | static int xtarget_option(target *t, scanner *sc) |
1135 | { |
1136 | xtarget *xt = (xtarget *)t; |
1137 | return (exec_option(xt ? &xt->x : 0, sc)); |
1138 | } |
1139 | |
1140 | /* --- @read@ --- */ |
1141 | |
1142 | static target *xtarget_read(scanner *sc) |
1143 | { |
1144 | xtarget *xt; |
1145 | dstr d = DSTR_INIT; |
1146 | |
1147 | if (!conf_prefix(sc, "exec")) |
1148 | return (0); |
1149 | xt = CREATE(xtarget); |
1150 | xt->t.ops = &xtarget_ops; |
1151 | exec_read(&xt->x, sc); |
1152 | exec_desc(&xt->x, &d); |
1153 | xt->t.desc = xstrdup(d.buf); |
1154 | dstr_destroy(&d); |
1155 | return (&xt->t); |
1156 | } |
1157 | |
1158 | /* --- @create@ --- */ |
1159 | |
1160 | static endpt *xtarget_create(target *t, const char *desc) |
1161 | { |
1162 | xtarget *xt = (xtarget *)t; |
1163 | endpt *e = exec_endpt(&xt->x, desc); |
1164 | return (e); |
1165 | } |
1166 | |
1167 | /* --- @destroy@ --- */ |
1168 | |
1169 | static void xtarget_destroy(target *t) |
1170 | { |
1171 | xtarget *xt = (xtarget *)t; |
372a98e2 |
1172 | free(xt->t.desc); |
48bb1f76 |
1173 | exec_destroy(&xt->x); |
1174 | DESTROY(xt); |
1175 | } |
1176 | |
1177 | /* --- Exec target operations --- */ |
1178 | |
1179 | target_ops xtarget_ops = { |
1180 | "exec", |
1181 | xtarget_option, xtarget_read, xtarget_create, xtarget_destroy |
1182 | }; |
1183 | |
1184 | /*----- That's all, folks -------------------------------------------------*/ |