source: branches/samhain-2_2-branch/src/sh_extern.c@ 553

Last change on this file since 553 was 50, checked in by rainer, 18 years ago

Fix for the fix in revision 48. Released as 2.2.1c
File size: 31.4 KB
Line 
1/* SAMHAIN file system integrity testing */
2/* Copyright (C) 2000,2004 Rainer Wichmann */
3/* */
4/* This program is free software; you can redistribute it */
5/* and/or modify */
6/* it under the terms of the GNU General Public License as */
7/* published by */
8/* the Free Software Foundation; either version 2 of the License, or */
9/* (at your option) any later version. */
10/* */
11/* This program is distributed in the hope that it will be useful, */
12/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
13/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
14/* GNU General Public License for more details. */
15/* */
16/* You should have received a copy of the GNU General Public License */
17/* along with this program; if not, write to the Free Software */
18/* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
19
20
21#include "config_xor.h"
22
23
24#include <stdio.h>
25#include <string.h>
26#ifdef HAVE_MEMORY_H
27#include <memory.h>
28#endif
29
30/* replace #if 0 by #if 1 and set an appropriate path in front of '/pdbg.'
31 * for debugging
32 */
33#if 0
34#define PDGBFILE "/pdbg."
35#endif
36
37
38#if defined(PDGBFILE)
39static FILE * pdbg = NULL;
40static FILE * pdbgc = NULL;
41#define PDBG_OPEN if (pdbg == NULL) pdbg = fopen(PDGBFILE"main", "a")
42#define PDBG_CLOSE fclose (pdbg); pdbg = NULL
43#define PDBG(arg) fprintf(pdbg, "PDBG: step %d\n", arg); fflush(pdbg)
44#define PDBG_D(arg) fprintf(pdbg, "PDBG: %d\n", arg); fflush(pdbg)
45#define PDBG_S(arg) fprintf(pdbg, "PDBG: %s\n", arg); fflush(pdbg)
46
47#define PDBGC_OPEN if (pdbgc == NULL) pdbgc = fopen(PDGBFILE"child", "a")
48#define PDBGC_CLOSE fclose (pdbgc); pdbgc = NULL
49#define PDBGC(arg) fprintf(pdbgc, "PDBGC: step %d\n", arg); fflush(pdbgc)
50#define PDBGC_D(arg) fprintf(pdbgc, "PDBGC: %d\n", arg); fflush(pdbgc)
51#define PDBGC_S(arg) fprintf(pdbgc, "PDBGC: %s\n", arg); fflush(pdbgc)
52#else
53#define PDBG_OPEN
54#define PDBG_CLOSE
55#define PDBG(arg)
56#define PDBG_D(arg)
57#define PDBG_S(arg)
58#define PDBGC_OPEN
59#define PDBGC_CLOSE
60#define PDBGC(arg)
61#define PDBGC_D(arg)
62#define PDBGC_S(arg)
63#endif
64
65
66#include <stdlib.h>
67#include <pwd.h>
68#include <unistd.h>
69#include <fcntl.h>
70#include <signal.h>
71#include <sys/stat.h>
72#include <sys/types.h>
73#include <errno.h>
74#include <sys/wait.h>
75
76#if TIME_WITH_SYS_TIME
77#include <sys/time.h>
78#include <time.h>
79#else
80#if HAVE_SYS_TIME_H
81#include <sys/time.h>
82#else
83#include <time.h>
84#endif
85#endif
86
87
88#include "samhain.h"
89#include "sh_utils.h"
90#include "sh_unix.h"
91#include "sh_tiger.h"
92#include "sh_extern.h"
93#include "sh_calls.h"
94#define SH_NEED_PWD_GRP 1
95#include "sh_static.h"
96
97
98#undef FIL__
99#define FIL__ _("sh_extern.c")
100
101extern int get_the_fd (SL_TICKET ticket);
102
103/*
104 * -- generic safe popen
105 */
106
107int sh_ext_popen (sh_tas_t * task)
108{
109 long status = 0;
110 int flags;
111 char * tmp;
112 char * tmp2;
113 int errnum;
114 int pipedes[2];
115 FILE * outf = NULL;
116 char * envp[1];
117 char * argp[2];
118
119 char * errfile;
120
121 static int some_error = 0;
122
123#if defined (__linux__)
124 SL_TICKET fd = -1;
125 char pname[128];
126 int pfd = -1;
127#endif
128
129 SL_ENTER(_("sh_ext_popen"));
130
131 /* Linux, HP-UX and FreeBSD will happily accept envp = argp = NULL
132 * Solaris (and probably some other Unices)
133 * needs a valid *envp[] with envp[0] = NULL;
134 * and similarly for argp
135 * OpenBSD finally needs non-null argp[0] ...
136 */
137 argp[0] = task->command;
138 argp[1] = NULL;
139 envp[0] = NULL;
140
141 /*
142 * -- check whether path is trustworthy
143 */
144 if ((uid_t) -1 != task->trusted_users[0])
145 {
146 status = sl_trustfile(task->command, task->trusted_users, NULL);
147 }
148
149 PDBG_OPEN;
150 PDBG_D( (int) status);
151
152 if ( SL_ENONE != status)
153 {
154 PDBG_S("SL_ENONE != status");
155 if (some_error == 0)
156 {
157 tmp = sh_util_safe_name (task->command);
158 errfile = sl_trust_errfile();
159 if (errfile[0] != '\0')
160 {
161 tmp2 = sh_util_safe_name (sl_trust_errfile());
162 sh_error_handle((-1), FIL__, __LINE__, status, MSG_E_TRUST2,
163 sl_error_string((int)status), tmp, tmp2);
164 SH_FREE(tmp2);
165 }
166 else
167 {
168 sh_error_handle((-1), FIL__, __LINE__, status, MSG_E_TRUST1,
169 sl_error_string((int)status), tmp);
170 }
171 SH_FREE(tmp);
172 }
173 some_error = 1;
174 SL_RETURN ((-1), _("sh_ext_popen"));
175 }
176
177 PDBG(1);
178
179 /*
180 * -- check whether the checksum is correct; with linux emulate fdexec
181 */
182#if !defined(__linux__) && !defined(SL_DEBUG)
183 if (task->checksum[0] != '\0')
184 {
185 PDBG_S("checksum test");
186 if (0 != sl_strcmp(task->checksum,
187 sh_tiger_hash (task->command, TIGER_FILE, 0))
188 )
189 {
190 PDBG_S("checksum mismatch");
191 if (some_error == 0)
192 {
193 tmp = sh_util_safe_name (task->command);
194 sh_error_handle((-1), FIL__, __LINE__, 0, MSG_E_HASH, tmp);
195 SH_FREE(tmp);
196 }
197 some_error = 1;
198 SL_RETURN ((-1), _("sh_ext_popen"));
199 }
200 }
201#endif
202
203 some_error = 0;
204
205 PDBG(2);
206
207 /*
208 * -- Create the pipe
209 */
210 if (aud_pipe(FIL__, __LINE__, pipedes) < 0)
211 {
212 PDBG_S("pipe() failure");
213 errnum = errno;
214 sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_E_SUBGEN,
215 sh_error_message(errnum), _("pipe"));
216 SL_RETURN ((-1), _("sh_ext_popen"));
217 }
218
219 PDBG(3);
220
221 /*
222 * -- Fork
223 */
224 task->pid = aud_fork(FIL__, __LINE__);
225
226 if (task->pid == (pid_t) - 1)
227 {
228 PDBG_S("fork() failure");
229 /*@-usedef@*/
230 (void) close(pipedes[0]);
231 (void) close(pipedes[1]);
232 /*@+usedef@*/
233 errnum = errno;
234 sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_E_SUBGEN,
235 sh_error_message(errnum), _("fork"));
236 SL_RETURN ((-1), _("sh_ext_popen"));
237 }
238
239 PDBG(4);
240
241 if (task->pid == (pid_t) 0)
242 {
243 /*
244 * -- fork again, if requested
245 */
246 if (S_TRUE == task->fork_twice)
247 {
248 task->pid = aud_fork(FIL__, __LINE__);
249
250 if (task->pid == (pid_t) - 1)
251 {
252 aud__exit (FIL__, __LINE__, EXIT_FAILURE);
253 }
254 }
255
256 if (task->pid == (pid_t) 0)
257 {
258 PDBGC_OPEN;
259 PDBGC(1);
260
261 /*
262 * -- grandchild - make write side of the pipe stdin
263 */
264 if (task->rw == 'w')
265 {
266 if (retry_aud_dup2(FIL__, __LINE__,
267 pipedes[STDIN_FILENO], STDIN_FILENO) < 0)
268 aud__exit(FIL__, __LINE__,EXIT_FAILURE);
269 }
270 else
271 {
272 if (retry_aud_dup2(FIL__, __LINE__,
273 pipedes[STDOUT_FILENO], STDOUT_FILENO) < 0)
274 aud__exit(FIL__, __LINE__,EXIT_FAILURE);
275 }
276 PDBGC(2);
277
278
279 /* close the pipe descriptors
280 */
281 (void) close (pipedes[STDIN_FILENO]);
282 (void) close (pipedes[STDOUT_FILENO]);
283
284 /* don't leak file descriptors
285 */
286#if !defined(PDGBFILE)
287 sh_unix_closeall (3, task->com_fd); /* in child process */
288#endif
289
290 /* drop root privileges, if possible && requested
291 */
292 if (task->privileged == 0 && 0 == getuid())
293 {
294 PDBGC_S("privileged");
295
296 /* zero priv info
297 */
298 memset(skey, 0, sizeof(sh_key_t));
299
300 (void) aud_setgid(FIL__, __LINE__,(gid_t) task->run_user_gid);
301 (void) aud_setuid(FIL__, __LINE__,(uid_t) task->run_user_uid);
302 /* make sure we cannot get root again
303 */
304 if (aud_setuid(FIL__, __LINE__,0) >= 0)
305 aud__exit(FIL__, __LINE__,EXIT_FAILURE);
306 }
307
308 PDBGC(3);
309 (void) fflush(NULL);
310
311 if (task->rw == 'w')
312 {
313 PDBGC_S("w");
314 (void) fcntl (STDOUT_FILENO, F_SETFD, FD_CLOEXEC);
315 (void) fcntl (STDERR_FILENO, F_SETFD, FD_CLOEXEC);
316 /*
317 freopen(_("/dev/null"), "r+", stderr);
318 freopen(_("/dev/null"), "r+", stdout);
319 */
320 }
321 else
322 {
323 PDBGC_S("r");
324 (void) retry_aud_dup2 (FIL__, __LINE__,
325 STDOUT_FILENO, STDERR_FILENO);
326 (void) fcntl (STDIN_FILENO, F_SETFD, FD_CLOEXEC);
327 /*
328 freopen(_("/dev/null"), "r+", stdin);
329 */
330 }
331
332 PDBGC(4);
333
334
335#if defined(__linux__)
336 /*
337 * -- emulate an fdexec with checksum testing
338 */
339 if (task->checksum[0] != '\0')
340 {
341 PDBGC_S("fexecve");
342 if (task->com_fd != (-1))
343 {
344 pfd = retry_aud_dup(FIL__, __LINE__, task->com_fd);
345 if (pfd < 0)
346 {
347 PDBGC_S("fexecve: dup2 failed");
348 aud__exit(FIL__, __LINE__, EXIT_FAILURE);
349 }
350 }
351 else
352 {
353 fd =
354 sl_open_read(task->command,
355 task->privileged==0 ? SL_NOPRIV : SL_YESPRIV);
356 tiger_fd = fd;
357 if (0 != sl_strcmp(task->checksum,
358 sh_tiger_hash (task->command,
359 TIGER_FD, 0)))
360 {
361 PDBGC_S("fexecve: checksum mismatch");
362 aud__exit(FIL__, __LINE__, EXIT_FAILURE);
363 }
364 pfd = get_the_fd(fd);
365 }
366
367 PDBGC(5);
368 sl_snprintf(pname, sizeof(pname), _("/proc/self/fd/%d"), pfd);
369 if (access(pname, R_OK|X_OK) == 0) /* flawfinder: ignore */
370 {
371 PDBGC(6);
372 PDBGC_CLOSE;
373 fcntl (pfd, F_SETFD, FD_CLOEXEC);
374 retry_aud_execve (FIL__, __LINE__,
375 pname,
376 (task->argc == 0) ? NULL : task->argv,
377 (task->envc == 0) ? NULL : task->envv
378 );
379
380 errnum = errno;
381 PDBGC_OPEN;
382 PDBGC_S(strerror(errnum));
383 PDBGC_S(task->command);
384 PDBGC_S("fexecve: failed");
385 PDBGC_CLOSE;
386 /* failed
387 */
388 aud__exit(FIL__, __LINE__, EXIT_FAILURE);
389 }
390 PDBGC_S("fexecve: not working");
391 /*
392 * procfs not working, go ahead; checksum is tested already
393 */
394 if (fd != -1)
395 sl_close(fd);
396 else if (pfd != -1)
397 close(fd);
398 }
399#endif
400
401 PDBGC_S(" -- non fexecve --");
402 /*
403 * -- execute path if executable
404 */
405 if (0 == access(task->command, R_OK|X_OK)) /* flawfinder: ignore */
406 {
407 PDBGC(5);
408 PDBGC_CLOSE;
409 (void) retry_aud_execve (FIL__, __LINE__,
410 task->command,
411 (task->argc == 0) ? argp : task->argv,
412 (task->envc == 0) ? envp : task->envv
413 );
414 }
415 errnum = errno;
416 PDBGC_OPEN;
417 PDBGC_S(strerror(errnum));
418 PDBGC_S(task->command);
419 PDBGC_S("execve: failed");
420 PDBGC_CLOSE;
421 /* failed
422 */
423 aud__exit(FIL__, __LINE__, EXIT_FAILURE);
424 }
425 /*
426 * if we have forked twice, this is parent::detached_subprocess
427 */
428 if (S_TRUE == task->fork_twice)
429 {
430 aud__exit (FIL__, __LINE__, 0);
431 }
432 }
433
434
435 /*
436 * -- parent; task->pid is child pid; exit status is status of
437 * grandchild if exited
438 */
439 if (S_TRUE == task->fork_twice)
440 {
441 (void) waitpid (task->pid, NULL, 0);
442 }
443
444 PDBG(5);
445 /* open an output stream on top of the write side of the pipe
446 */
447 if (task->rw == 'w')
448 {
449 PDBG_S("is w");
450 (void) close (pipedes[STDIN_FILENO]);
451 (void) retry_fcntl (FIL__, __LINE__, pipedes[STDOUT_FILENO],
452 F_SETFD, FD_CLOEXEC);
453 outf = fdopen (pipedes[STDOUT_FILENO], "w");
454 }
455 else
456 {
457 PDBG_S("is r");
458 (void) close (pipedes[STDOUT_FILENO]);
459 (void) retry_fcntl (FIL__, __LINE__, pipedes[STDIN_FILENO],
460 F_SETFD, FD_CLOEXEC);
461 outf = fdopen (pipedes[STDIN_FILENO], "r");
462 }
463
464 if (outf == NULL)
465 {
466 errnum = errno;
467 PDBG_S("outf == NULL");
468 tmp = sh_util_safe_name (task->command);
469
470 if (task->privileged == 0 && 0 == getuid())
471 sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_NOEXEC,
472 (UID_CAST) task->run_user_uid, tmp);
473 else
474 sh_error_handle((-1), FIL__, __LINE__, errnum, MSG_NOEXEC,
475 (UID_CAST) getuid(), tmp);
476
477 SH_FREE(tmp);
478
479 (void) aud_kill (FIL__, __LINE__, task->pid, SIGKILL);
480 (void) close (pipedes[STDOUT_FILENO]);
481 (void) close (pipedes[STDIN_FILENO]);
482 (void) waitpid (task->pid, NULL, 0);
483 task->pid = 0;
484
485 SL_RETURN ((-1), _("sh_ext_popen"));
486 }
487
488 if (task->rw == 'w')
489 task->pipeFD = pipedes[STDOUT_FILENO];
490 else
491 task->pipeFD = pipedes[STDIN_FILENO];
492
493 PDBG_D(task->pipeFD);
494
495 task->pipeTI = sl_make_ticket(task->pipeFD, _("pipe"));
496
497 flags = (int) retry_fcntl (FIL__, __LINE__, task->pipeFD, F_GETFL, 0);
498 if (flags != (-1))
499 (void) retry_fcntl (FIL__, __LINE__, task->pipeFD,
500 F_SETFL, flags|O_NONBLOCK);
501 task->pipe = outf;
502
503 PDBG_S("return from popen");
504 PDBG_CLOSE;
505
506 SL_RETURN (0, _("sh_ext_popen"));
507}
508
509/*
510 * -- close the pipe
511 */
512extern int flag_err_debug;
513
514int sh_ext_pclose (sh_tas_t * task)
515{
516 int status = 0;
517 int retry = 0;
518 pid_t retval;
519 char infomsg[256];
520
521 SL_ENTER(_("sh_ext_pclose"));
522
523 PDBGC_OPEN;
524 PDBG_S(" -> pclose");
525 (void) fflush(task->pipe);
526 (void) fclose(task->pipe);
527 if (!SL_ISERROR(task->pipeTI))
528 (void) sl_close(task->pipeTI);
529
530 task->pipe = NULL;
531 task->pipeFD = (-1);
532 task->pipeTI = SL_ETICKET;
533
534 if (S_FALSE == task->fork_twice)
535 {
536 infomsg[0] = '\0';
537
538 nochmal:
539 retval = waitpid(task->pid, &(task->exit_status), WNOHANG|WUNTRACED);
540 /*@-bufferoverflowhigh@*/
541 if (task->pid == retval)
542 {
543 if (WIFEXITED(task->exit_status) != 0)
544 {
545 task->exit_status = WEXITSTATUS(task->exit_status);
546 if ((flag_err_debug == SL_TRUE) || (task->exit_status != 0))
547 sl_snprintf(infomsg, sizeof(infomsg),
548 _("Subprocess exited normally with status %d"),
549 task->exit_status);
550 }
551 else if (WIFSIGNALED(task->exit_status) != 0)
552 {
553 sl_snprintf(infomsg, sizeof(infomsg),
554 _("Subprocess terminated by signal %d"),
555 WTERMSIG(task->exit_status));
556 task->exit_status = EXIT_FAILURE;
557 }
558 else if (WIFSTOPPED(task->exit_status) != 0)
559 {
560 sl_snprintf(infomsg, sizeof(infomsg),
561 _("Subprocess stopped by signal %d, killing"),
562 WSTOPSIG(task->exit_status));
563 task->exit_status = EXIT_FAILURE;
564 (void) aud_kill (FIL__, __LINE__, task->pid, 9);
565 (void) retry_msleep (0, 30);
566 (void) waitpid (task->pid, NULL, WNOHANG|WUNTRACED);
567 }
568 else
569 {
570 sl_snprintf(infomsg, sizeof(infomsg),
571 _("Subprocess exit status unknown"));
572 task->exit_status = EXIT_FAILURE;
573 }
574 }
575 else if (0 == retval)
576 {
577 if (retry < 3)
578 {
579 ++retry;
580 (void) retry_msleep(0, (retry * 30));
581 goto nochmal;
582 }
583 (void) aud_kill (FIL__, __LINE__, task->pid, 9);
584 sl_snprintf(infomsg, sizeof(infomsg),
585 _("Subprocess not yet exited, killing"));
586 task->exit_status = EXIT_FAILURE;
587 (void) waitpid (task->pid, NULL, 0);
588 }
589 else
590 {
591 sl_snprintf(infomsg, sizeof(infomsg),
592 _("Waitpid returned error %d\n"), errno);
593 task->exit_status = EXIT_FAILURE;
594 }
595 /*@+bufferoverflowhigh@*/
596 status = task->exit_status;
597 if (flag_err_debug == SL_TRUE)
598 {
599 sh_error_handle(SH_ERR_ALL, FIL__, __LINE__, task->exit_status,
600 MSG_E_SUBGEN, infomsg, _("sh_ext_pclose"));
601 }
602 else if (status != 0)
603 {
604 sh_error_handle(SH_ERR_INFO, FIL__, __LINE__, task->exit_status,
605 MSG_E_SUBGEN, infomsg, _("sh_ext_pclose"));
606 }
607 }
608
609 task->pid = 0;
610 task->exit_status = 0;
611 PDBG_S(" <--");
612 PDBG_CLOSE;
613 SL_RETURN (status, _("sh_ext_pclose"));
614}
615
616void sh_ext_tas_init (sh_tas_t * tas)
617{
618 int i;
619
620 tas->command = NULL;
621 tas->argc = 0;
622 tas->envc = 0;
623 tas->checksum[0] = '\0';
624 tas->pipeFD = (-1);
625 tas->pipeTI = SL_ETICKET;
626 tas->pid = (pid_t) -1;
627 tas->privileged = 1;
628 tas->pipe = NULL;
629 tas->rw = 'w';
630 tas->exit_status = 0;
631 tas->fork_twice = S_TRUE;
632
633 for (i = 0; i < 32; ++i)
634 {
635 tas->argv[i] = NULL;
636 tas->envv[i] = NULL;
637 tas->trusted_users[i] = (uid_t) -1;
638 }
639
640 tas->run_user_uid = (uid_t) getuid();
641 tas->run_user_gid = (gid_t) getgid();
642
643 tas->com_fd = -1;
644 tas->com_ti = -1;
645 return;
646}
647
648
649int sh_ext_tas_add_envv(sh_tas_t * tas, const char * key, const char * val)
650{
651 size_t sk = 0, sv = 0;
652 int si;
653
654 SL_ENTER(_("sh_ext_tas_add_envv"));
655
656 if (tas == NULL || (key == NULL && val == NULL) ||
657 tas->envc >= 30)
658 {
659 SL_RETURN (-1, _("sh_ext_tas_add_envv"));
660 }
661 if (key != NULL)
662 sk = strlen(key) + 1;
663 if (val != NULL)
664 sv = strlen(val) + 1;
665
666 if (!sl_ok_adds(sk, sv))
667 {
668 SL_RETURN (-1, _("sh_ext_tas_add_envv"));
669 }
670 si = tas->envc;
671 tas->envv[si] = SH_ALLOC(sk + sv);
672
673 if (key != NULL)
674 {
675 (void) sl_strlcpy(tas->envv[si], key, sk+sv);
676 (void) sl_strlcat(tas->envv[si], "=", sk+sv);
677 if (val != NULL)
678 (void) sl_strlcat(tas->envv[si], val, sk+sv);
679 }
680 else
681 (void) sl_strlcpy(tas->envv[si], val, sv);
682
683 ++(tas->envc);
684 SL_RETURN ((tas->envc), _("sh_ext_tas_add_envv"));
685}
686
687int sh_ext_tas_rm_argv(sh_tas_t * tas)
688{
689 int last;
690
691 SL_ENTER(_("sh_ext_tas_rm_argv"));
692 if (tas == NULL || tas->argc == 0)
693 {
694 SL_RETURN (-1, _("sh_ext_tas_rm_argv"));
695 }
696
697 last = (tas->argc - 1);
698 --(tas->argc);
699 SH_FREE(tas->argv[last]);
700 tas->argv[last] = NULL;
701 SL_RETURN ((tas->argc), _("sh_ext_tas_rm_argv"));
702}
703
704int sh_ext_tas_add_argv(sh_tas_t * tas, const char * val)
705{
706 size_t sv = 0;
707 int si;
708
709 SL_ENTER(_("sh_ext_tas_add_argv"));
710
711 if (tas == NULL || val == NULL ||
712 tas->argc >= 30)
713 {
714 SL_RETURN (-1, _("sh_ext_tas_add_argv"));
715 }
716
717 if (val != NULL)
718 sv = strlen(val) + 1;
719
720 si = tas->argc;
721 tas->argv[si] = SH_ALLOC(sv);
722
723 (void) sl_strlcpy(tas->argv[si], val, sv);
724
725 ++(tas->argc);
726 SL_RETURN ((tas->argc), _("sh_ext_tas_add_argv"));
727}
728
729void sh_ext_tas_command(sh_tas_t * tas, const char * command)
730{
731 size_t len = sl_strlen(command);
732 tas->command = SH_ALLOC(len+1);
733 (void) sl_strlcpy(tas->command, command, len+1);
734 return;
735}
736
737void sh_ext_tas_free(sh_tas_t * tas)
738{
739 int i;
740 if (NULL != tas->command) SH_FREE(tas->command);
741
742 for (i = 0; i < 32; ++i)
743 {
744 if (NULL != tas->argv[i]) SH_FREE(tas->argv[i]);
745 if (NULL != tas->envv[i]) SH_FREE(tas->envv[i]);
746 }
747
748 if (tas->com_ti != (-1))
749 {
750 (void) sl_close(tas->com_ti);
751 tas->com_ti = -1;
752 tas->com_fd = -1;
753 }
754
755 return;
756}
757
758
759/* --------------- EXTERN STUFF ------------------- */
760
761#if defined(WITH_EXTERNAL)
762
763typedef struct _sh_com_t
764{
765 char type[4];
766
767 int for_c;
768 char * for_v[32];
769 int fand_c;
770 char * fand_v[32];
771 int fnot_c;
772 char * fnot_v[32];
773 time_t deadtime;
774 time_t last_run;
775
776 sh_tas_t tas;
777
778 struct _sh_com_t * next;
779
780} sh_com_t;
781
782
783static
784void set3 (char * pos, char c1, char c2, char c3)
785{
786 pos[0] = c1;
787 pos[1] = c2;
788 pos[2] = c3;
789 pos[3] = '\0';
790 return;
791}
792
793
794
795/* initialize the external command structure
796 */
797static
798sh_com_t * command_init(void)
799{
800 int i;
801 uid_t ff_euid;
802 sh_com_t * ext_com = NULL;
803
804 SL_ENTER(_("command_init"));
805
806 ext_com = (sh_com_t *) SH_ALLOC(sizeof(sh_com_t));
807
808 if (!ext_com)
809 {
810 SL_RETURN( NULL, ("command_init"));
811 }
812
813 sh_ext_tas_init (&(ext_com->tas));
814
815 (void) sl_get_euid(&ff_euid);
816 ext_com->tas.trusted_users[0] = (uid_t) 0;
817 ext_com->tas.trusted_users[1] = (uid_t) (ff_euid);
818
819 /* ------------------------------------------------- */
820
821 set3(ext_com->type, 'l', 'o', 'g');
822 ext_com->for_c = 0;
823 ext_com->fand_c = 0;
824 ext_com->fnot_c = 0;
825 ext_com->deadtime = 0;
826 ext_com->last_run = 0;
827
828 for (i = 0; i < 32; ++i)
829 {
830 ext_com->for_v[i] = NULL;
831 ext_com->fand_v[i] = NULL;
832 ext_com->fnot_v[i] = NULL;
833 }
834 ext_com->next = NULL;
835
836 SL_RETURN( ext_com, ("command_init"));
837}
838
839/* the list of external commands
840 */
841static sh_com_t * ext_coms = NULL;
842
843/* if -1, allocation of last command has failed,
844 * thus don't fill in options
845 */
846static int ext_failed = -1;
847
848static
849int sh_ext_add_envv(const char * key, const char * val)
850{
851 int retval;
852
853 SL_ENTER(_("sh_ext_add_envv"));
854
855 if (ext_coms == NULL || ext_failed == (-1) ||
856 (key == NULL && val == NULL) ||
857 ext_coms->tas.envc >= 30)
858 {
859 SL_RETURN (-1, _("sh_ext_add_envv"));
860 }
861
862 retval = sh_ext_tas_add_envv(&(ext_coms->tas), key, val);
863
864 if (retval >= 0)
865 retval = 0;
866
867 SL_RETURN (retval, _("sh_ext_add_envv"));
868}
869
870
871
872static
873int sh_ext_init(const char * command)
874{
875 sh_com_t * retval;
876 size_t size;
877
878 SL_ENTER(_("sh_ext_init"));
879
880 if (command == NULL)
881 {
882 SL_RETURN (-1, _("sh_ext_init"));
883 }
884 size = strlen(command);
885 if (command[0] != '/' || size < 2)
886 {
887 SL_RETURN (-1, _("sh_ext_init"));
888 }
889
890 if (NULL == (retval = command_init()))
891 {
892 SL_RETURN (-1, _("sh_ext_init"));
893 }
894
895 sh_ext_tas_command(&(retval->tas), command);
896
897 if (sh.timezone != NULL)
898 {
899 (void) sh_ext_add_envv( "TZ", sh.timezone);
900 }
901
902 retval->next = ext_coms;
903 ext_coms = retval;
904 SL_RETURN (0, _("sh_ext_init"));
905}
906
907static
908int sh_ext_uid (const char * user, /*@out@*/uid_t * uid, /*@out@*/gid_t * gid)
909{
910 struct passwd * tempres;
911
912 SL_ENTER(_("sh_ext_uid"));
913
914 *uid = (uid_t)-1; *gid = (gid_t)-1;
915
916 if (user == NULL)
917 {
918 SL_RETURN (-1, _("sh_ext_uid"));
919 }
920 tempres = sh_getpwnam(user);
921
922 if (NULL != tempres)
923 {
924 *uid = tempres->pw_uid;
925 *gid = tempres->pw_gid;
926 SL_RETURN (0, _("sh_ext_uid"));
927 }
928
929 SL_RETURN (-1, _("sh_ext_uid"));
930}
931
932
933static
934int sh_ext_add (const char * argstring, int * ntok, char * stok[])
935{
936 int i = 0;
937 size_t s;
938 char * p;
939 char * new;
940 size_t len;
941
942 SL_ENTER(_("sh_ext_add"));
943
944 if (NULL == argstring)
945 {
946 SL_RETURN((-1), _("sh_ext_add"));
947 }
948
949 len = strlen(argstring) + 1;
950 new = SH_ALLOC(len);
951 sl_strlcpy(new, argstring, len);
952
953 do
954 {
955 if (i == 0)
956 p = strtok (new, ", \t");
957 else
958 p = strtok (NULL, ", \t");
959 if (p == NULL)
960 break;
961
962 s = strlen(p) + 1;
963 if (stok[i] != NULL)
964 SH_FREE(stok[i]);
965 stok[i] = SH_ALLOC(s);
966 (void) sl_strlcpy(stok[i], p, s);
967
968 ++i;
969 if (i == 30)
970 break;
971 }
972 while (p != NULL);
973
974 *ntok = i;
975 SH_FREE(new);
976
977 SL_RETURN (0, _("sh_ext_add"));
978}
979
980/*********************************************************
981 *
982 * Public functions
983 *
984 *
985 *********************************************************/
986
987/*
988 * -- start a new external command, and add it to the list
989 */
990int sh_ext_setcommand(const char * cmd)
991{
992 int i;
993
994 SL_ENTER(_("sh_ext_setcommand"));
995 if ( (i = sh_ext_init(cmd)) < 0)
996 ext_failed = -1;
997 else
998 ext_failed = 0;
999 SL_RETURN( i, _("sh_ext_setcommand"));
1000}
1001
1002
1003/*
1004 * -- clean up the command list
1005 */
1006int sh_ext_cleanup(void)
1007{
1008 int i;
1009 sh_com_t * retval;
1010
1011 SL_ENTER(_("sh_ext_cleanup"));
1012
1013 while (ext_coms != NULL)
1014 {
1015 retval = ext_coms;
1016 ext_coms = retval->next;
1017
1018 sh_ext_tas_free (&(retval->tas));
1019
1020 for (i = 0; i < 32; ++i)
1021 {
1022 if (NULL != retval->for_v[i]) SH_FREE(retval->for_v[i]);
1023 if (NULL != retval->fand_v[i]) SH_FREE(retval->fand_v[i]);
1024 if (NULL != retval->fnot_v[i]) SH_FREE(retval->fnot_v[i]);
1025 }
1026
1027 SH_FREE(retval);
1028
1029 }
1030
1031 SL_RETURN (0, _("sh_ext_cleanup"));
1032}
1033
1034/*
1035 * -- add keywords to the OR filter
1036 */
1037int sh_ext_add_or (const char * str)
1038{
1039 if (ext_coms == NULL || ext_failed == (-1))
1040 return (-1);
1041 return (sh_ext_add (str, &(ext_coms->for_c), ext_coms->for_v));
1042}
1043
1044/*
1045 * -- add keywords to the AND filter
1046 */
1047int sh_ext_add_and (const char * str)
1048{
1049 if (ext_coms == NULL || ext_failed == (-1))
1050 return (-1);
1051 return (sh_ext_add (str, &(ext_coms->fand_c), ext_coms->fand_v));
1052}
1053
1054/*
1055 * -- add keywords to the NOT filter
1056 */
1057int sh_ext_add_not (const char * str)
1058{
1059 if (ext_coms == NULL || ext_failed == (-1))
1060 return (-1);
1061 return (sh_ext_add (str, &(ext_coms->fnot_c), ext_coms->fnot_v));
1062}
1063
1064/*
1065 * -- add keywords to the CL argument list
1066 */
1067int sh_ext_add_argv (const char * str)
1068{
1069 if (ext_coms == NULL || ext_failed == (-1))
1070 return (-1);
1071 return (sh_ext_add (str, &(ext_coms->tas.argc), ext_coms->tas.argv));
1072}
1073
1074/*
1075 * -- add a path to the environment
1076 */
1077int sh_ext_add_default (const char * dummy)
1078{
1079 char * p = NULL;
1080 int i;
1081
1082 SL_ENTER(_("sh_ext_add_default"));
1083 if (dummy[0] == 'n' || dummy[0] == 'N' ||
1084 dummy[0] == 'f' || dummy[0] == 'F' || dummy[0] == '0')
1085 {
1086 SL_RETURN(0, _("sh_ext_add_default"));
1087 }
1088 p = sh_unix_getUIDdir (SH_ERR_ERR, (uid_t) ext_coms->tas.run_user_uid);
1089 if (p)
1090 (void) sh_ext_add_envv (_("HOME"), p);
1091 (void) sh_ext_add_envv (_("SHELL"), _("/bin/sh"));
1092 (void) sh_ext_add_envv (_("PATH"), _("/sbin:/usr/sbin:/bin:/usr/bin"));
1093 i = (p == NULL ? (-1) : 0);
1094 SL_RETURN(i, _("sh_ext_add_default"));
1095}
1096
1097/*
1098 * -- add an environment variable
1099 */
1100int sh_ext_add_environ (const char * str)
1101{
1102 int i;
1103
1104 SL_ENTER(_("sh_ext_add_environ"));
1105 i = sh_ext_add_envv (NULL, str);
1106 SL_RETURN(i, _("sh_ext_add_environ"));
1107}
1108
1109/*
1110 * -- set deadtime
1111 */
1112int sh_ext_deadtime (const char * str)
1113{
1114 long deadtime = 0;
1115 char * tail = NULL;
1116
1117 SL_ENTER(_("sh_ext_deadtime"));
1118
1119 if (ext_coms == NULL || ext_failed == (-1) || str == NULL)
1120 {
1121 SL_RETURN (-1, ("sh_ext_deadtime"));
1122 }
1123 deadtime = strtol(str, &tail, 10);
1124 if (tail == str || deadtime < 0 || deadtime == LONG_MAX)
1125 {
1126 SL_RETURN (-1, ("sh_ext_deadtime"));
1127 }
1128
1129 ext_coms->deadtime = (time_t) deadtime;
1130 SL_RETURN (0, ("sh_ext_deadtime"));
1131}
1132
1133/*
1134 * -- define type
1135 */
1136int sh_ext_type (const char * str)
1137{
1138 SL_ENTER(_("sh_ext_type"));
1139
1140 if (ext_coms == NULL || ext_failed == (-1) || str == NULL)
1141 {
1142 SL_RETURN((-1), _("sh_ext_type"));
1143 }
1144
1145 if (strlen(str) != 3)
1146 {
1147 SL_RETURN((-1), _("sh_ext_type"));
1148 }
1149
1150 set3(ext_coms->type, str[0], str[1], str[2]);
1151
1152 if (str[0] == 'l' && str[1] == 'o' && str[2] == 'g')
1153 ext_coms->tas.rw = 'w';
1154 else if (str[0] == 's' && str[1] == 'r' && str[2] == 'v')
1155 ext_coms->tas.rw = 'w';
1156 else if (str[0] == 'm' && str[1] == 'o' && str[2] == 'n')
1157 ext_coms->tas.rw = 'r';
1158 else
1159 {
1160 SL_RETURN((-1), _("sh_ext_type"));
1161 }
1162
1163 SL_RETURN(0, _("sh_ext_type"));
1164}
1165
1166
1167
1168/*
1169 * -- define checksum
1170 */
1171int sh_ext_checksum (const char * str)
1172{
1173 SL_ENTER(_("sh_ext_checksum"));
1174 if (ext_coms == NULL || ext_failed == (-1) || str == NULL)
1175 {
1176 SL_RETURN((-1), _("sh_ext_checksum"));
1177 }
1178
1179 if (sl_strlen(str) != KEY_LEN)
1180 {
1181 SL_RETURN((-1), _("sh_ext_checksum"));
1182 }
1183
1184 (void) sl_strlcpy (ext_coms->tas.checksum, str, KEY_LEN+1);
1185
1186 SL_RETURN((0), _("sh_ext_checksum"));
1187}
1188
1189/*
1190 * -- choose privileges
1191 */
1192int sh_ext_priv (const char * c)
1193{
1194
1195 uid_t me_uid;
1196 gid_t me_gid;
1197
1198 SL_ENTER(_("sh_ext_priv"));
1199 if (0 == sh_ext_uid (c, &me_uid, &me_gid))
1200 {
1201 ext_coms->tas.run_user_uid = me_uid;
1202 ext_coms->tas.run_user_gid = me_gid;
1203 if (me_uid != (uid_t) 0)
1204 ext_coms->tas.privileged = 0;
1205 SL_RETURN((0), _("sh_ext_priv"));
1206 }
1207
1208 SL_RETURN (-1, _("sh_ext_priv"));
1209}
1210
1211
1212
1213
1214/*
1215 * -- check filters
1216 */
1217static int sh_ext_filter (char * message, sh_com_t * task)
1218{
1219 int i;
1220 int j = 0;
1221 time_t now_time;
1222
1223 SL_ENTER(_("sh_ext_filter"));
1224
1225 /* Presence of any of these keywords prevents execution.
1226 */
1227 if (task->fnot_c > 0)
1228 {
1229 for (i = 0; i < task->fnot_c; ++i)
1230 {
1231 if (NULL != sl_strstr(message, task->fnot_v[i]))
1232 {
1233 SL_RETURN ((-1), _("sh_ext_filter"));
1234 }
1235 }
1236 }
1237
1238 /* Presence of all of these keywords is required for execution.
1239 */
1240 if (task->fand_c > 0)
1241 {
1242 j = 0;
1243
1244 for (i = 0; i < task->fand_c; ++i)
1245 if (NULL != sl_strstr(message, task->fand_v[i]))
1246 ++j;
1247
1248 if (j != task->fand_c)
1249 {
1250 SL_RETURN ((-1), _("sh_ext_filter"));
1251 }
1252
1253 }
1254
1255 /* Presence of at least one of these keywords is required for execution.
1256 */
1257 if (task->for_c > 0)
1258 {
1259 for (i = 0; i < task->for_c; ++i)
1260 {
1261 if (NULL != sl_strstr(message, task->for_v[i]))
1262 {
1263 goto checkdeadtime;
1264 }
1265 }
1266 SL_RETURN ((-1), _("sh_ext_filter"));
1267 }
1268
1269 checkdeadtime:
1270 if (task->deadtime != (time_t) 0) /* deadtime */
1271 {
1272 now_time = time (NULL);
1273
1274 if (task->last_run == (time_t) 0)
1275 {
1276 task->last_run = now_time;
1277 }
1278 else if ((time_t)(now_time-task->last_run) < task->deadtime)
1279 {
1280 SL_RETURN ((-1), _("sh_ext_filter"));
1281 }
1282 else
1283 {
1284 task->last_run = now_time;
1285 }
1286 }
1287
1288 SL_RETURN ((0), _("sh_ext_filter"));
1289}
1290
1291
1292
1293/*
1294 * -- execute external script/program
1295 */
1296int sh_ext_execute (char t1, char t2, char t3, /*@null@*/char * message,
1297 size_t msg_siz)
1298{
1299 int caperr;
1300 sh_com_t * listval = ext_coms;
1301 int status = 0;
1302 char * tmp;
1303
1304 static int some_error = 0;
1305
1306 struct sigaction new_act;
1307 struct sigaction old_act;
1308
1309 SL_ENTER(_("sh_ext_execute"));
1310
1311 PDBG_OPEN;
1312
1313 if (listval == NULL || message == NULL)
1314 {
1315 SL_RETURN ((-1), _("sh_ext_execute"));
1316 }
1317
1318 PDBG(-1);
1319
1320 if (msg_siz == 0)
1321 msg_siz = sl_strlen(message);
1322
1323
1324 /* ignore SIGPIPE (instead get EPIPE if connection is closed)
1325 */
1326 new_act.sa_handler = SIG_IGN;
1327 (void) retry_sigaction (FIL__, __LINE__, SIGPIPE, &new_act, &old_act);
1328
1329 while (listval != NULL)
1330 {
1331 PDBG(-2);
1332 if (t1 == listval->type[0] &&
1333 t2 == listval->type[1] &&
1334 t3 == listval->type[2] &&
1335 0 == sh_ext_filter (message, listval))
1336 {
1337 PDBG(-3);
1338
1339 if (0 != (caperr = sl_get_cap_sub()))
1340 {
1341 sh_error_handle((-1), FIL__, __LINE__, caperr, MSG_E_SUBGEN,
1342 sh_error_message (caperr),
1343 _("sl_get_cap_sub"));
1344 }
1345 if (0 == sh_ext_popen (&(listval->tas)))
1346 {
1347 PDBG_OPEN;
1348 PDBG(-4);
1349 if (NULL != listval->tas.pipe && listval->tas.rw == 'w')
1350 {
1351 PDBG(-5);
1352 if (message != NULL)
1353 {
1354 PDBG(-6);
1355 status = (int) write (listval->tas.pipeFD,
1356 message, msg_siz);
1357 if (status >= 0)
1358 status = (int) write (listval->tas.pipeFD, "\n", 1);
1359 }
1360 PDBG_D(status);
1361 if (status >= 0)
1362 status = (int) write (listval->tas.pipeFD, "[", 1);
1363 PDBG_D(status);
1364 if (status >= 0)
1365 status = (int) write (listval->tas.pipeFD, "E", 1);
1366 PDBG_D(status);
1367 if (status >= 0)
1368 status = (int) write (listval->tas.pipeFD, "O", 1);
1369 PDBG_D(status);
1370 if (status >= 0)
1371 status = (int) write (listval->tas.pipeFD, "F", 1);
1372 PDBG_D(status);
1373 if (status >= 0)
1374 status = (int) write (listval->tas.pipeFD, "]", 1);
1375 PDBG_D(status);
1376 if (status >= 0)
1377 status = (int) write (listval->tas.pipeFD, "\n", 1);
1378 PDBG_D(status);
1379 if (status >= 0)
1380 {
1381 some_error = 0;
1382 }
1383 if ((status < 0) && (some_error == 0))
1384 {
1385 some_error = 1;
1386 PDBG_S("some error");
1387 PDBG_D(status);
1388 tmp = sh_util_safe_name (listval->tas.command);
1389
1390 if (tmp)
1391 {
1392 if (listval->tas.privileged == 0 &&
1393 (0 == getuid() || 0 != sl_is_suid()) )
1394 sh_error_handle((-1), FIL__, __LINE__, 0,
1395 MSG_NOEXEC,
1396 (UID_CAST) listval->tas.run_user_uid,
1397 tmp);
1398 else
1399 sh_error_handle((-1), FIL__, __LINE__, 0,
1400 MSG_NOEXEC,
1401 (UID_CAST) getuid(), tmp);
1402
1403 SH_FREE(tmp);
1404 }
1405
1406 }
1407 PDBG(-7);
1408 (void) fflush(listval->tas.pipe);
1409 }
1410 PDBG(-8);
1411 (void) sh_ext_pclose(&(listval->tas));
1412 }
1413 else
1414 {
1415 PDBG_OPEN;
1416 PDBG_S("0 != sh_ext_popen()");
1417 }
1418 if (0 != (caperr = sl_drop_cap_sub()))
1419 {
1420 sh_error_handle((-1), FIL__, __LINE__, caperr, MSG_E_SUBGEN,
1421 sh_error_message (caperr),
1422 _("sl_drop_cap_sub"));
1423 }
1424
1425 }
1426 listval = listval->next;
1427 }
1428 PDBG_OPEN;
1429 PDBG_S("no more commands");
1430
1431 /* restore old signal handler
1432 */
1433 (void) retry_sigaction (FIL__, __LINE__, SIGPIPE, &old_act, NULL);
1434 PDBG_S("return");
1435 PDBG_CLOSE;
1436
1437 SL_RETURN ((0), _("sh_ext_execute"));
1438}
1439
1440
1441/* #if defined(WITH_EXTERNAL) */
1442#endif
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