Line data Source code
1 : /*
2 : Unix SMB/CIFS implementation.
3 : Samba system utilities
4 : Copyright (C) Andrew Tridgell 1992-1998
5 : Copyright (C) Jeremy Allison 1998-2005
6 : Copyright (C) Timur Bakeyev 2005
7 : Copyright (C) Bjoern Jacke 2006-2007
8 :
9 : This program is free software; you can redistribute it and/or modify
10 : it under the terms of the GNU General Public License as published by
11 : the Free Software Foundation; either version 3 of the License, or
12 : (at your option) any later version.
13 :
14 : This program is distributed in the hope that it will be useful,
15 : but WITHOUT ANY WARRANTY; without even the implied warranty of
16 : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 : GNU General Public License for more details.
18 :
19 : You should have received a copy of the GNU General Public License
20 : along with this program. If not, see <http://www.gnu.org/licenses/>.
21 : */
22 :
23 : #include "includes.h"
24 : #include "system/syslog.h"
25 : #include "system/capability.h"
26 : #include "system/passwd.h"
27 : #include "system/filesys.h"
28 : #include "lib/util/setid.h"
29 : #include "lib/util/time.h"
30 :
31 : #ifdef HAVE_SYS_SYSCTL_H
32 : #include <sys/sysctl.h>
33 : #endif
34 :
35 : #ifdef HAVE_SYS_PRCTL_H
36 : #include <sys/prctl.h>
37 : #endif
38 :
39 : /*
40 : The idea is that this file will eventually have wrappers around all
41 : important system calls in samba. The aims are:
42 :
43 : - to enable easier porting by putting OS dependent stuff in here
44 :
45 : - to allow for hooks into other "pseudo-filesystems"
46 :
47 : - to allow easier integration of things like the japanese extensions
48 :
49 : - to support the philosophy of Samba to expose the features of
50 : the OS within the SMB model. In general whatever file/printer/variable
51 : expansions/etc make sense to the OS should be acceptable to Samba.
52 : */
53 :
54 : /*******************************************************************
55 : A send wrapper that will deal with EINTR or EAGAIN or EWOULDBLOCK.
56 : ********************************************************************/
57 :
58 0 : ssize_t sys_send(int s, const void *msg, size_t len, int flags)
59 : {
60 : ssize_t ret;
61 :
62 : do {
63 0 : ret = send(s, msg, len, flags);
64 0 : } while (ret == -1 && (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK));
65 :
66 0 : return ret;
67 : }
68 :
69 : /*******************************************************************
70 : A recvfrom wrapper that will deal with EINTR.
71 : NB. As used with non-blocking sockets, return on EAGAIN/EWOULDBLOCK
72 : ********************************************************************/
73 :
74 4302 : ssize_t sys_recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen)
75 : {
76 : ssize_t ret;
77 :
78 : do {
79 4302 : ret = recvfrom(s, buf, len, flags, from, fromlen);
80 4302 : } while (ret == -1 && (errno == EINTR));
81 4302 : return ret;
82 : }
83 :
84 : /*******************************************************************
85 : A fcntl wrapper that will deal with EINTR.
86 : ********************************************************************/
87 :
88 822 : int sys_fcntl_ptr(int fd, int cmd, void *arg)
89 : {
90 : int ret;
91 :
92 : do {
93 822 : ret = fcntl(fd, cmd, arg);
94 822 : } while (ret == -1 && errno == EINTR);
95 822 : return ret;
96 : }
97 :
98 : /*******************************************************************
99 : A fcntl wrapper that will deal with EINTR.
100 : ********************************************************************/
101 :
102 0 : int sys_fcntl_long(int fd, int cmd, long arg)
103 : {
104 : int ret;
105 :
106 : do {
107 0 : ret = fcntl(fd, cmd, arg);
108 0 : } while (ret == -1 && errno == EINTR);
109 0 : return ret;
110 : }
111 :
112 : /*******************************************************************
113 : A fcntl wrapper that will deal with EINTR.
114 : ********************************************************************/
115 :
116 2392 : int sys_fcntl_int(int fd, int cmd, int arg)
117 : {
118 : int ret;
119 :
120 : do {
121 2392 : ret = fcntl(fd, cmd, arg);
122 2392 : } while (ret == -1 && errno == EINTR);
123 2392 : return ret;
124 : }
125 :
126 : /****************************************************************************
127 : Return the best approximation to a 'create time' under UNIX from a stat
128 : structure.
129 : ****************************************************************************/
130 :
131 716203 : static struct timespec calc_create_time_stat(const struct stat *st)
132 : {
133 : struct timespec ret, ret1;
134 716203 : struct timespec c_time = get_ctimespec(st);
135 716203 : struct timespec m_time = get_mtimespec(st);
136 716203 : struct timespec a_time = get_atimespec(st);
137 :
138 716203 : ret = timespec_compare(&c_time, &m_time) < 0 ? c_time : m_time;
139 716203 : ret1 = timespec_compare(&ret, &a_time) < 0 ? ret : a_time;
140 :
141 716203 : if(!null_timespec(ret1)) {
142 716203 : return ret1;
143 : }
144 :
145 : /*
146 : * One of ctime, mtime or atime was zero (probably atime).
147 : * Just return MIN(ctime, mtime).
148 : */
149 0 : return ret;
150 : }
151 :
152 : /****************************************************************************
153 : Return the best approximation to a 'create time' under UNIX from a stat_ex
154 : structure.
155 : ****************************************************************************/
156 :
157 265 : static struct timespec calc_create_time_stat_ex(const struct stat_ex *st)
158 : {
159 : struct timespec ret, ret1;
160 265 : struct timespec c_time = st->st_ex_ctime;
161 265 : struct timespec m_time = st->st_ex_mtime;
162 265 : struct timespec a_time = st->st_ex_atime;
163 :
164 265 : ret = timespec_compare(&c_time, &m_time) < 0 ? c_time : m_time;
165 265 : ret1 = timespec_compare(&ret, &a_time) < 0 ? ret : a_time;
166 :
167 265 : if(!null_timespec(ret1)) {
168 265 : return ret1;
169 : }
170 :
171 : /*
172 : * One of ctime, mtime or atime was zero (probably atime).
173 : * Just return MIN(ctime, mtime).
174 : */
175 0 : return ret;
176 : }
177 :
178 : /****************************************************************************
179 : Return the 'create time' from a stat struct if it exists (birthtime) or else
180 : use the best approximation.
181 : ****************************************************************************/
182 :
183 716203 : static void make_create_timespec(const struct stat *pst, struct stat_ex *dst,
184 : bool fake_dir_create_times)
185 : {
186 716203 : if (S_ISDIR(pst->st_mode) && fake_dir_create_times) {
187 0 : dst->st_ex_btime.tv_sec = 315493200L; /* 1/1/1980 */
188 0 : dst->st_ex_btime.tv_nsec = 0;
189 0 : return;
190 : }
191 :
192 716203 : dst->st_ex_iflags &= ~ST_EX_IFLAG_CALCULATED_BTIME;
193 :
194 : #if defined(HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC)
195 : dst->st_ex_btime = pst->st_birthtimespec;
196 : #elif defined(HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC)
197 : dst->st_ex_btime.tv_sec = pst->st_birthtime;
198 : dst->st_ex_btime.tv_nsec = pst->st_birthtimenspec;
199 : #elif defined(HAVE_STRUCT_STAT_ST_BIRTHTIME)
200 : dst->st_ex_btime.tv_sec = pst->st_birthtime;
201 : dst->st_ex_btime.tv_nsec = 0;
202 : #else
203 716203 : dst->st_ex_btime = calc_create_time_stat(pst);
204 716203 : dst->st_ex_iflags |= ST_EX_IFLAG_CALCULATED_BTIME;
205 : #endif
206 :
207 : /* Deal with systems that don't initialize birthtime correctly.
208 : * Pointed out by SATOH Fumiyasu <fumiyas@osstech.jp>.
209 : */
210 716203 : if (null_timespec(dst->st_ex_btime)) {
211 0 : dst->st_ex_btime = calc_create_time_stat(pst);
212 0 : dst->st_ex_iflags |= ST_EX_IFLAG_CALCULATED_BTIME;
213 : }
214 : }
215 :
216 : /****************************************************************************
217 : If we update a timestamp in a stat_ex struct we may have to recalculate
218 : the birthtime. For now only implement this for write time, but we may
219 : also need to do it for atime and ctime. JRA.
220 : ****************************************************************************/
221 :
222 2733 : void update_stat_ex_mtime(struct stat_ex *dst,
223 : struct timespec write_ts)
224 : {
225 2733 : dst->st_ex_mtime = write_ts;
226 :
227 : /* We may have to recalculate btime. */
228 2733 : if (dst->st_ex_iflags & ST_EX_IFLAG_CALCULATED_BTIME) {
229 265 : dst->st_ex_btime = calc_create_time_stat_ex(dst);
230 : }
231 2733 : }
232 :
233 22185 : void update_stat_ex_create_time(struct stat_ex *dst,
234 : struct timespec create_time)
235 : {
236 22185 : dst->st_ex_btime = create_time;
237 22185 : dst->st_ex_iflags &= ~ST_EX_IFLAG_CALCULATED_BTIME;
238 22185 : }
239 :
240 33903 : void update_stat_ex_from_saved_stat(struct stat_ex *dst,
241 : const struct stat_ex *src)
242 : {
243 33903 : if (!VALID_STAT(*src)) {
244 7669 : return;
245 : }
246 :
247 26234 : if (!(src->st_ex_iflags & ST_EX_IFLAG_CALCULATED_BTIME)) {
248 8833 : update_stat_ex_create_time(dst, src->st_ex_btime);
249 : }
250 : }
251 :
252 716203 : void init_stat_ex_from_stat (struct stat_ex *dst,
253 : const struct stat *src,
254 : bool fake_dir_create_times)
255 : {
256 716203 : dst->st_ex_dev = src->st_dev;
257 716203 : dst->st_ex_ino = src->st_ino;
258 716203 : dst->st_ex_mode = src->st_mode;
259 716203 : dst->st_ex_nlink = src->st_nlink;
260 716203 : dst->st_ex_uid = src->st_uid;
261 716203 : dst->st_ex_gid = src->st_gid;
262 716203 : dst->st_ex_rdev = src->st_rdev;
263 716203 : dst->st_ex_size = src->st_size;
264 716203 : dst->st_ex_atime = get_atimespec(src);
265 716203 : dst->st_ex_mtime = get_mtimespec(src);
266 716203 : dst->st_ex_ctime = get_ctimespec(src);
267 716203 : dst->st_ex_iflags = 0;
268 716203 : make_create_timespec(src, dst, fake_dir_create_times);
269 : #ifdef HAVE_STAT_ST_BLKSIZE
270 716203 : dst->st_ex_blksize = src->st_blksize;
271 : #else
272 : dst->st_ex_blksize = STAT_ST_BLOCKSIZE;
273 : #endif
274 :
275 : #ifdef HAVE_STAT_ST_BLOCKS
276 716203 : dst->st_ex_blocks = src->st_blocks;
277 : #else
278 : dst->st_ex_blocks = src->st_size / dst->st_ex_blksize + 1;
279 : #endif
280 :
281 : #ifdef HAVE_STAT_ST_FLAGS
282 : dst->st_ex_flags = src->st_flags;
283 : #else
284 716203 : dst->st_ex_flags = 0;
285 : #endif
286 716203 : }
287 :
288 : /*******************************************************************
289 : A stat() wrapper.
290 : ********************************************************************/
291 :
292 154891 : int sys_stat(const char *fname, SMB_STRUCT_STAT *sbuf,
293 : bool fake_dir_create_times)
294 : {
295 : int ret;
296 : struct stat statbuf;
297 154891 : ret = stat(fname, &statbuf);
298 154891 : if (ret == 0) {
299 : /* we always want directories to appear zero size */
300 143018 : if (S_ISDIR(statbuf.st_mode)) {
301 141513 : statbuf.st_size = 0;
302 : }
303 143018 : init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
304 : }
305 154891 : return ret;
306 : }
307 :
308 : /*******************************************************************
309 : An fstat() wrapper.
310 : ********************************************************************/
311 :
312 548510 : int sys_fstat(int fd, SMB_STRUCT_STAT *sbuf, bool fake_dir_create_times)
313 : {
314 : int ret;
315 : struct stat statbuf;
316 548510 : ret = fstat(fd, &statbuf);
317 548510 : if (ret == 0) {
318 : /* we always want directories to appear zero size */
319 548510 : if (S_ISDIR(statbuf.st_mode)) {
320 485819 : statbuf.st_size = 0;
321 : }
322 548510 : init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
323 : }
324 548510 : return ret;
325 : }
326 :
327 : /*******************************************************************
328 : An lstat() wrapper.
329 : ********************************************************************/
330 :
331 816 : int sys_lstat(const char *fname,SMB_STRUCT_STAT *sbuf,
332 : bool fake_dir_create_times)
333 : {
334 : int ret;
335 : struct stat statbuf;
336 816 : ret = lstat(fname, &statbuf);
337 816 : if (ret == 0) {
338 : /* we always want directories to appear zero size */
339 816 : if (S_ISDIR(statbuf.st_mode)) {
340 810 : statbuf.st_size = 0;
341 : }
342 816 : init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
343 : }
344 816 : return ret;
345 : }
346 :
347 : /*******************************************************************
348 : An fstatat() wrapper.
349 : ********************************************************************/
350 :
351 23859 : int sys_fstatat(int fd,
352 : const char *pathname,
353 : SMB_STRUCT_STAT *sbuf,
354 : int flags,
355 : bool fake_dir_create_times)
356 : {
357 : int ret;
358 : struct stat statbuf;
359 :
360 23859 : ret = fstatat(fd, pathname, &statbuf, flags);
361 23859 : if (ret != 0) {
362 0 : return -1;
363 : }
364 :
365 : /* we always want directories to appear zero size */
366 23859 : if (S_ISDIR(statbuf.st_mode)) {
367 11495 : statbuf.st_size = 0;
368 : }
369 23859 : init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
370 23859 : return 0;
371 : }
372 :
373 : /*******************************************************************
374 : An posix_fallocate() wrapper.
375 : ********************************************************************/
376 0 : int sys_posix_fallocate(int fd, off_t offset, off_t len)
377 : {
378 : #if defined(HAVE_POSIX_FALLOCATE)
379 0 : return posix_fallocate(fd, offset, len);
380 : #elif defined(F_RESVSP64)
381 : /* this handles XFS on IRIX */
382 : struct flock64 fl;
383 : off_t new_len = offset + len;
384 : int ret;
385 : struct stat64 sbuf;
386 :
387 : /* unlikely to get a too large file on a 64bit system but ... */
388 : if (new_len < 0)
389 : return EFBIG;
390 :
391 : fl.l_whence = SEEK_SET;
392 : fl.l_start = offset;
393 : fl.l_len = len;
394 :
395 : ret=fcntl(fd, F_RESVSP64, &fl);
396 :
397 : if (ret != 0)
398 : return errno;
399 :
400 : /* Make sure the file gets enlarged after we allocated space: */
401 : fstat64(fd, &sbuf);
402 : if (new_len > sbuf.st_size)
403 : ftruncate64(fd, new_len);
404 : return 0;
405 : #else
406 : return ENOSYS;
407 : #endif
408 : }
409 :
410 : /*******************************************************************
411 : An fallocate() function that matches the semantics of the Linux one.
412 : ********************************************************************/
413 :
414 : #ifdef HAVE_LINUX_FALLOC_H
415 : #include <linux/falloc.h>
416 : #endif
417 :
418 0 : int sys_fallocate(int fd, uint32_t mode, off_t offset, off_t len)
419 : {
420 : #if defined(HAVE_LINUX_FALLOCATE)
421 0 : int lmode = 0;
422 :
423 0 : if (mode & VFS_FALLOCATE_FL_KEEP_SIZE) {
424 0 : lmode |= FALLOC_FL_KEEP_SIZE;
425 0 : mode &= ~VFS_FALLOCATE_FL_KEEP_SIZE;
426 : }
427 :
428 : #if defined(HAVE_FALLOC_FL_PUNCH_HOLE)
429 0 : if (mode & VFS_FALLOCATE_FL_PUNCH_HOLE) {
430 0 : lmode |= FALLOC_FL_PUNCH_HOLE;
431 0 : mode &= ~VFS_FALLOCATE_FL_PUNCH_HOLE;
432 : }
433 : #endif /* HAVE_FALLOC_FL_PUNCH_HOLE */
434 :
435 0 : if (mode != 0) {
436 0 : DEBUG(2, ("unmapped fallocate flags: %lx\n",
437 : (unsigned long)mode));
438 0 : errno = EINVAL;
439 0 : return -1;
440 : }
441 0 : return fallocate(fd, lmode, offset, len);
442 : #else /* HAVE_LINUX_FALLOCATE */
443 : /* TODO - plumb in fallocate from other filesysetms like VXFS etc. JRA. */
444 : errno = ENOSYS;
445 : return -1;
446 : #endif /* HAVE_LINUX_FALLOCATE */
447 : }
448 :
449 : /*******************************************************************
450 : An fdopendir wrapper.
451 : ********************************************************************/
452 :
453 6397 : DIR *sys_fdopendir(int fd)
454 : {
455 : #if defined(HAVE_FDOPENDIR)
456 6397 : return fdopendir(fd);
457 : #else
458 : errno = ENOSYS;
459 : return NULL;
460 : #endif
461 : }
462 :
463 : /*******************************************************************
464 : An mknod() wrapper.
465 : ********************************************************************/
466 :
467 0 : int sys_mknod(const char *path, mode_t mode, SMB_DEV_T dev)
468 : {
469 : #if defined(HAVE_MKNOD)
470 0 : return mknod(path, mode, dev);
471 : #else
472 : /* No mknod system call. */
473 : errno = ENOSYS;
474 : return -1;
475 : #endif
476 : }
477 :
478 : /*******************************************************************
479 : A mknodat() wrapper.
480 : ********************************************************************/
481 :
482 0 : int sys_mknodat(int dirfd, const char *path, mode_t mode, SMB_DEV_T dev)
483 : {
484 : #if defined(HAVE_MKNODAT)
485 0 : return mknodat(dirfd, path, mode, dev);
486 : #else
487 : /* No mknod system call. */
488 : errno = ENOSYS;
489 : return -1;
490 : #endif
491 : }
492 :
493 : /*******************************************************************
494 : System wrapper for getwd. Always returns MALLOC'ed memory, or NULL
495 : on error (malloc fail usually).
496 : ********************************************************************/
497 :
498 12608 : char *sys_getwd(void)
499 : {
500 : #ifdef GETCWD_TAKES_NULL
501 12608 : return getcwd(NULL, 0);
502 : #elif defined(HAVE_GETCWD)
503 : char *wd = NULL, *s = NULL;
504 : size_t allocated = PATH_MAX;
505 :
506 : while (1) {
507 : s = SMB_REALLOC_ARRAY(s, char, allocated);
508 : if (s == NULL) {
509 : return NULL;
510 : }
511 : wd = getcwd(s, allocated);
512 : if (wd) {
513 : break;
514 : }
515 : if (errno != ERANGE) {
516 : int saved_errno = errno;
517 : SAFE_FREE(s);
518 : errno = saved_errno;
519 : break;
520 : }
521 : allocated *= 2;
522 : if (allocated < PATH_MAX) {
523 : SAFE_FREE(s);
524 : break;
525 : }
526 : }
527 : return wd;
528 : #else
529 : char *wd = NULL;
530 : char *s = SMB_MALLOC_ARRAY(char, PATH_MAX);
531 : if (s == NULL) {
532 : return NULL;
533 : }
534 : wd = getwd(s);
535 : if (wd == NULL) {
536 : int saved_errno = errno;
537 : SAFE_FREE(s);
538 : errno = saved_errno;
539 : }
540 : return wd;
541 : #endif
542 : }
543 :
544 : #if defined(HAVE_POSIX_CAPABILITIES)
545 :
546 : /**************************************************************************
547 : Try and abstract process capabilities (for systems that have them).
548 : ****************************************************************************/
549 :
550 : /* Set the POSIX capabilities needed for the given purpose into the effective
551 : * capability set of the current process. Make sure they are always removed
552 : * from the inheritable set, because there is no circumstance in which our
553 : * children should inherit our elevated privileges.
554 : */
555 14 : static bool set_process_capability(enum smbd_capability capability,
556 : bool enable)
557 : {
558 : /* "5" is the number of "num_cap_vals++" below */
559 14 : cap_value_t cap_vals[5] = {0};
560 14 : size_t num_cap_vals = 0;
561 :
562 : cap_t cap;
563 :
564 : #if defined(HAVE_PRCTL) && defined(PR_GET_KEEPCAPS) && defined(PR_SET_KEEPCAPS)
565 : /* On Linux, make sure that any capabilities we grab are sticky
566 : * across UID changes. We expect that this would allow us to keep both
567 : * the effective and permitted capability sets, but as of circa 2.6.16,
568 : * only the permitted set is kept. It is a bug (which we work around)
569 : * that the effective set is lost, but we still require the effective
570 : * set to be kept.
571 : */
572 14 : if (!prctl(PR_GET_KEEPCAPS)) {
573 5 : prctl(PR_SET_KEEPCAPS, 1);
574 : }
575 : #endif
576 :
577 14 : cap = cap_get_proc();
578 14 : if (cap == NULL) {
579 0 : DEBUG(0,("set_process_capability: cap_get_proc failed: %s\n",
580 : strerror(errno)));
581 0 : return False;
582 : }
583 :
584 14 : switch (capability) {
585 : /*
586 : * WARNING: If you add any #ifdef for a fresh
587 : * capability, bump up the array size in the
588 : * declaration of cap_vals[] above just to be
589 : * trivially safe to never overwrite cap_vals[].
590 : */
591 7 : case KERNEL_OPLOCK_CAPABILITY:
592 : #ifdef CAP_NETWORK_MGT
593 : /* IRIX has CAP_NETWORK_MGT for oplocks. */
594 : cap_vals[num_cap_vals++] = CAP_NETWORK_MGT;
595 : #endif
596 7 : break;
597 7 : case DMAPI_ACCESS_CAPABILITY:
598 : #ifdef CAP_DEVICE_MGT
599 : /* IRIX has CAP_DEVICE_MGT for DMAPI access. */
600 : cap_vals[num_cap_vals++] = CAP_DEVICE_MGT;
601 : #elif CAP_MKNOD
602 : /* Linux has CAP_MKNOD for DMAPI access. */
603 7 : cap_vals[num_cap_vals++] = CAP_MKNOD;
604 : #endif
605 7 : break;
606 0 : case LEASE_CAPABILITY:
607 : #ifdef CAP_LEASE
608 0 : cap_vals[num_cap_vals++] = CAP_LEASE;
609 : #endif
610 0 : break;
611 0 : case DAC_OVERRIDE_CAPABILITY:
612 : #ifdef CAP_DAC_OVERRIDE
613 0 : cap_vals[num_cap_vals++] = CAP_DAC_OVERRIDE;
614 : #endif
615 : }
616 :
617 14 : if (num_cap_vals == 0) {
618 7 : cap_free(cap);
619 7 : return True;
620 : }
621 :
622 7 : cap_set_flag(cap, CAP_EFFECTIVE, num_cap_vals, cap_vals,
623 : enable ? CAP_SET : CAP_CLEAR);
624 :
625 : /* We never want to pass capabilities down to our children, so make
626 : * sure they are not inherited.
627 : */
628 7 : cap_set_flag(cap, CAP_INHERITABLE, num_cap_vals, cap_vals, CAP_CLEAR);
629 :
630 7 : if (cap_set_proc(cap) == -1) {
631 0 : DEBUG(0, ("set_process_capability: cap_set_proc failed: %s\n",
632 : strerror(errno)));
633 0 : cap_free(cap);
634 0 : return False;
635 : }
636 :
637 7 : cap_free(cap);
638 7 : return True;
639 : }
640 :
641 : #endif /* HAVE_POSIX_CAPABILITIES */
642 :
643 : /****************************************************************************
644 : Gain the oplock capability from the kernel if possible.
645 : ****************************************************************************/
646 :
647 : #if defined(HAVE_POSIX_CAPABILITIES) && defined(CAP_DAC_OVERRIDE)
648 : static bool have_cap_dac_override = true;
649 : #else
650 : static bool have_cap_dac_override = false;
651 : #endif
652 :
653 0 : void set_effective_capability(enum smbd_capability capability)
654 : {
655 0 : bool ret = false;
656 :
657 0 : if (capability != DAC_OVERRIDE_CAPABILITY || have_cap_dac_override) {
658 : #if defined(HAVE_POSIX_CAPABILITIES)
659 0 : ret = set_process_capability(capability, True);
660 : #endif /* HAVE_POSIX_CAPABILITIES */
661 : }
662 :
663 : /*
664 : * Fallback to become_root() if CAP_DAC_OVERRIDE is not
665 : * available.
666 : */
667 0 : if (capability == DAC_OVERRIDE_CAPABILITY) {
668 0 : if (!ret) {
669 0 : have_cap_dac_override = false;
670 : }
671 0 : if (!have_cap_dac_override) {
672 0 : become_root();
673 : }
674 : }
675 0 : }
676 :
677 14 : void drop_effective_capability(enum smbd_capability capability)
678 : {
679 14 : if (capability != DAC_OVERRIDE_CAPABILITY || have_cap_dac_override) {
680 : #if defined(HAVE_POSIX_CAPABILITIES)
681 14 : set_process_capability(capability, False);
682 : #endif /* HAVE_POSIX_CAPABILITIES */
683 : } else {
684 0 : unbecome_root();
685 : }
686 14 : }
687 :
688 : /**************************************************************************
689 : Wrapper for random().
690 : ****************************************************************************/
691 :
692 200 : long sys_random(void)
693 : {
694 : #if defined(HAVE_RANDOM)
695 200 : return (long)random();
696 : #elif defined(HAVE_RAND)
697 : return (long)rand();
698 : #else
699 : DEBUG(0,("Error - no random function available !\n"));
700 : exit(1);
701 : #endif
702 : }
703 :
704 : /**************************************************************************
705 : Wrapper for srandom().
706 : ****************************************************************************/
707 :
708 23 : void sys_srandom(unsigned int seed)
709 : {
710 : #if defined(HAVE_SRANDOM)
711 23 : srandom(seed);
712 : #elif defined(HAVE_SRAND)
713 : srand(seed);
714 : #else
715 : DEBUG(0,("Error - no srandom function available !\n"));
716 : exit(1);
717 : #endif
718 23 : }
719 :
720 : #ifndef NGROUPS_MAX
721 : #define NGROUPS_MAX 32 /* Guess... */
722 : #endif
723 :
724 : /**************************************************************************
725 : Returns equivalent to NGROUPS_MAX - using sysconf if needed.
726 : ****************************************************************************/
727 :
728 2786 : int setgroups_max(void)
729 : {
730 : #if defined(SYSCONF_SC_NGROUPS_MAX)
731 2786 : int ret = sysconf(_SC_NGROUPS_MAX);
732 2786 : return (ret == -1) ? NGROUPS_MAX : ret;
733 : #else
734 : return NGROUPS_MAX;
735 : #endif
736 : }
737 :
738 2786 : int getgroups_max(void)
739 : {
740 : #if defined(DARWINOS)
741 : /*
742 : * On MacOS sysconf(_SC_NGROUPS_MAX) returns 16 due to MacOS's group
743 : * nesting. However, The initgroups() manpage states the following:
744 : * "Note that OS X supports group membership in an unlimited number
745 : * of groups. The OS X kernel uses the group list stored in the process
746 : * credentials only as an initial cache. Additional group memberships
747 : * are determined by communication between the operating system and the
748 : * opendirectoryd daemon."
749 : */
750 : return INT_MAX;
751 : #else
752 2786 : return setgroups_max();
753 : #endif
754 : }
755 :
756 : /**************************************************************************
757 : Wrap setgroups and getgroups for systems that declare getgroups() as
758 : returning an array of gid_t, but actuall return an array of int.
759 : ****************************************************************************/
760 :
761 : #if defined(HAVE_BROKEN_GETGROUPS)
762 :
763 : #ifdef HAVE_BROKEN_GETGROUPS
764 : #define GID_T int
765 : #else
766 : #define GID_T gid_t
767 : #endif
768 :
769 : static int sys_broken_getgroups(int setlen, gid_t *gidset)
770 : {
771 : GID_T *group_list;
772 : int i, ngroups;
773 :
774 : if(setlen == 0) {
775 : return getgroups(0, NULL);
776 : }
777 :
778 : /*
779 : * Broken case. We need to allocate a
780 : * GID_T array of size setlen.
781 : */
782 :
783 : if(setlen < 0) {
784 : errno = EINVAL;
785 : return -1;
786 : }
787 :
788 : if((group_list = SMB_MALLOC_ARRAY(GID_T, setlen)) == NULL) {
789 : DEBUG(0,("sys_getgroups: Malloc fail.\n"));
790 : return -1;
791 : }
792 :
793 : if((ngroups = getgroups(setlen, group_list)) < 0) {
794 : int saved_errno = errno;
795 : SAFE_FREE(group_list);
796 : errno = saved_errno;
797 : return -1;
798 : }
799 :
800 : /*
801 : * We're safe here as if ngroups > setlen then
802 : * getgroups *must* return EINVAL.
803 : * pubs.opengroup.org/onlinepubs/009695399/functions/getgroups.html
804 : */
805 :
806 : for(i = 0; i < ngroups; i++)
807 : gidset[i] = (gid_t)group_list[i];
808 :
809 : SAFE_FREE(group_list);
810 : return ngroups;
811 : }
812 :
813 : static int sys_broken_setgroups(int setlen, gid_t *gidset)
814 : {
815 : GID_T *group_list;
816 : int i ;
817 :
818 : if (setlen == 0)
819 : return 0 ;
820 :
821 : if (setlen < 0 || setlen > setgroups_max()) {
822 : errno = EINVAL;
823 : return -1;
824 : }
825 :
826 : /*
827 : * Broken case. We need to allocate a
828 : * GID_T array of size setlen.
829 : */
830 :
831 : if((group_list = SMB_MALLOC_ARRAY(GID_T, setlen)) == NULL) {
832 : DEBUG(0,("sys_setgroups: Malloc fail.\n"));
833 : return -1;
834 : }
835 :
836 : for(i = 0; i < setlen; i++)
837 : group_list[i] = (GID_T) gidset[i];
838 :
839 : if(samba_setgroups(setlen, group_list) != 0) {
840 : int saved_errno = errno;
841 : SAFE_FREE(group_list);
842 : errno = saved_errno;
843 : return -1;
844 : }
845 :
846 : SAFE_FREE(group_list);
847 : return 0 ;
848 : }
849 :
850 : #endif /* HAVE_BROKEN_GETGROUPS */
851 :
852 : /* This is a list of systems that require the first GID passed to setgroups(2)
853 : * to be the effective GID. If your system is one of these, add it here.
854 : */
855 : #if defined (FREEBSD) || defined (DARWINOS)
856 : #define USE_BSD_SETGROUPS
857 : #endif
858 :
859 : #if defined(USE_BSD_SETGROUPS)
860 : /* Depending on the particular BSD implementation, the first GID that is
861 : * passed to setgroups(2) will either be ignored or will set the credential's
862 : * effective GID. In either case, the right thing to do is to guarantee that
863 : * gidset[0] is the effective GID.
864 : */
865 : static int sys_bsd_setgroups(gid_t primary_gid, int setlen, const gid_t *gidset)
866 : {
867 : gid_t *new_gidset = NULL;
868 : int max;
869 : int ret;
870 :
871 : /* setgroups(2) will fail with EINVAL if we pass too many groups. */
872 : max = setgroups_max();
873 :
874 : /* No group list, just make sure we are setting the efective GID. */
875 : if (setlen == 0) {
876 : return samba_setgroups(1, &primary_gid);
877 : }
878 :
879 : /* If the primary gid is not the first array element, grow the array
880 : * and insert it at the front.
881 : */
882 : if (gidset[0] != primary_gid) {
883 : new_gidset = SMB_MALLOC_ARRAY(gid_t, setlen + 1);
884 : if (new_gidset == NULL) {
885 : return -1;
886 : }
887 :
888 : memcpy(new_gidset + 1, gidset, (setlen * sizeof(gid_t)));
889 : new_gidset[0] = primary_gid;
890 : setlen++;
891 : }
892 :
893 : if (setlen > max) {
894 : DEBUG(3, ("forced to truncate group list from %d to %d\n",
895 : setlen, max));
896 : setlen = max;
897 : }
898 :
899 : #if defined(HAVE_BROKEN_GETGROUPS)
900 : ret = sys_broken_setgroups(setlen, new_gidset ? new_gidset : gidset);
901 : #else
902 : ret = samba_setgroups(setlen, new_gidset ? new_gidset : gidset);
903 : #endif
904 :
905 : if (new_gidset) {
906 : int errsav = errno;
907 : SAFE_FREE(new_gidset);
908 : errno = errsav;
909 : }
910 :
911 : return ret;
912 : }
913 :
914 : #endif /* USE_BSD_SETGROUPS */
915 :
916 : /**************************************************************************
917 : Wrapper for getgroups. Deals with broken (int) case.
918 : ****************************************************************************/
919 :
920 84149 : int sys_getgroups(int setlen, gid_t *gidset)
921 : {
922 : #if defined(HAVE_BROKEN_GETGROUPS)
923 : return sys_broken_getgroups(setlen, gidset);
924 : #else
925 84149 : return getgroups(setlen, gidset);
926 : #endif
927 : }
928 :
929 : /**************************************************************************
930 : Wrapper for setgroups. Deals with broken (int) case and BSD case.
931 : ****************************************************************************/
932 :
933 219598 : int sys_setgroups(gid_t UNUSED(primary_gid), int setlen, gid_t *gidset)
934 : {
935 : #if !defined(HAVE_SETGROUPS)
936 : errno = ENOSYS;
937 : return -1;
938 : #endif /* HAVE_SETGROUPS */
939 :
940 : #if defined(USE_BSD_SETGROUPS)
941 : return sys_bsd_setgroups(primary_gid, setlen, gidset);
942 : #elif defined(HAVE_BROKEN_GETGROUPS)
943 : return sys_broken_setgroups(setlen, gidset);
944 : #else
945 219598 : return samba_setgroups(setlen, gidset);
946 : #endif
947 : }
948 :
949 : /****************************************************************************
950 : Return the major devicenumber for UNIX extensions.
951 : ****************************************************************************/
952 :
953 0 : uint32_t unix_dev_major(SMB_DEV_T dev)
954 : {
955 : #if defined(HAVE_DEVICE_MAJOR_FN)
956 0 : return (uint32_t)major(dev);
957 : #else
958 : return (uint32_t)(dev >> 8);
959 : #endif
960 : }
961 :
962 : /****************************************************************************
963 : Return the minor devicenumber for UNIX extensions.
964 : ****************************************************************************/
965 :
966 0 : uint32_t unix_dev_minor(SMB_DEV_T dev)
967 : {
968 : #if defined(HAVE_DEVICE_MINOR_FN)
969 0 : return (uint32_t)minor(dev);
970 : #else
971 : return (uint32_t)(dev & 0xff);
972 : #endif
973 : }
974 :
975 : /**************************************************************************
976 : Wrapper for realpath.
977 : ****************************************************************************/
978 :
979 103486 : char *sys_realpath(const char *path)
980 : {
981 : char *result;
982 :
983 : #ifdef REALPATH_TAKES_NULL
984 103486 : result = realpath(path, NULL);
985 : #else
986 : result = SMB_MALLOC_ARRAY(char, PATH_MAX + 1);
987 : if (result) {
988 : char *resolved_path = realpath(path, result);
989 : if (!resolved_path) {
990 : SAFE_FREE(result);
991 : } else {
992 : /* SMB_ASSERT(result == resolved_path) ? */
993 : result = resolved_path;
994 : }
995 : }
996 : #endif
997 103486 : return result;
998 : }
999 :
1000 : #if 0
1001 : /*******************************************************************
1002 : Return the number of CPUs.
1003 : ********************************************************************/
1004 :
1005 : int sys_get_number_of_cores(void)
1006 : {
1007 : int ret = -1;
1008 :
1009 : #if defined(HAVE_SYSCONF)
1010 : #if defined(_SC_NPROCESSORS_ONLN)
1011 : ret = (int)sysconf(_SC_NPROCESSORS_ONLN);
1012 : #endif
1013 : #if defined(_SC_NPROCESSORS_CONF)
1014 : if (ret < 1) {
1015 : ret = (int)sysconf(_SC_NPROCESSORS_CONF);
1016 : }
1017 : #endif
1018 : #elif defined(HAVE_SYSCTL) && defined(CTL_HW)
1019 : int name[2];
1020 : unsigned int len = sizeof(ret);
1021 :
1022 : name[0] = CTL_HW;
1023 : #if defined(HW_AVAILCPU)
1024 : name[1] = HW_AVAILCPU;
1025 :
1026 : if (sysctl(name, 2, &ret, &len, NULL, 0) == -1) {
1027 : ret = -1;
1028 : }
1029 : #endif
1030 : #if defined(HW_NCPU)
1031 : if(ret < 1) {
1032 : name[0] = CTL_HW;
1033 : name[1] = HW_NCPU;
1034 : if (sysctl(nm, 2, &count, &len, NULL, 0) == -1) {
1035 : ret = -1;
1036 : }
1037 : }
1038 : #endif
1039 : #endif
1040 : if (ret < 1) {
1041 : ret = 1;
1042 : }
1043 : return ret;
1044 : }
1045 : #endif
1046 :
1047 : static struct proc_fd_pattern {
1048 : const char *pattern;
1049 : const char *test_path;
1050 : } proc_fd_patterns[] = {
1051 : /* Linux */
1052 : { "/proc/self/fd/%d", "/proc/self/fd/0" },
1053 : { NULL, NULL },
1054 : };
1055 :
1056 : static const char *proc_fd_pattern;
1057 :
1058 10906 : bool sys_have_proc_fds(void)
1059 : {
1060 : static bool checked;
1061 : static bool have_proc_fds;
1062 10906 : struct proc_fd_pattern *p = NULL;
1063 : struct stat sb;
1064 : int ret;
1065 :
1066 10906 : if (checked) {
1067 6037 : return have_proc_fds;
1068 : }
1069 :
1070 4869 : for (p = &proc_fd_patterns[0]; p->test_path != NULL; p++) {
1071 4869 : ret = stat(p->test_path, &sb);
1072 4869 : if (ret != 0) {
1073 0 : continue;
1074 : }
1075 4869 : have_proc_fds = true;
1076 4869 : proc_fd_pattern = p->pattern;
1077 4869 : break;
1078 : }
1079 :
1080 4869 : checked = true;
1081 4869 : return have_proc_fds;
1082 : }
1083 :
1084 2936 : const char *sys_proc_fd_path(int fd, char *buf, size_t bufsize)
1085 : {
1086 : int written;
1087 :
1088 2936 : if (!sys_have_proc_fds()) {
1089 0 : return NULL;
1090 : }
1091 :
1092 : #if defined(__clang__)
1093 : #pragma clang diagnostic push
1094 : #pragma clang diagnostic ignored "-Wformat-nonliteral"
1095 : #endif
1096 2936 : written = snprintf(buf,
1097 : bufsize,
1098 : proc_fd_pattern,
1099 : fd);
1100 : #if defined(__clang__)
1101 : #pragma clang diagnostic pop
1102 : #endif
1103 2936 : if (written >= bufsize) {
1104 0 : return NULL;
1105 : }
1106 :
1107 2936 : return buf;
1108 : }
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