source3/lib/system.c

   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
  30 #ifdef HAVE_SYS_SYSCTL_H
  31 #include <sys/sysctl.h>
  32 #endif
  33
  34 #ifdef HAVE_SYS_PRCTL_H
  35 #include <sys/prctl.h>
  36 #endif
  37
  38 /*
  39    The idea is that this file will eventually have wrappers around all
  40    important system calls in samba. The aims are:
  41
  42    - to enable easier porting by putting OS dependent stuff in here
  43
  44    - to allow for hooks into other "pseudo-filesystems"
  45
  46    - to allow easier integration of things like the japanese extensions
  47
  48    - to support the philosophy of Samba to expose the features of
  49      the OS within the SMB model. In general whatever file/printer/variable
  50      expansions/etc make sense to the OS should be acceptable to Samba.
  51 */
  52
  53
  54
  55 /*******************************************************************
  56 A read wrapper that will deal with EINTR.
  57 ********************************************************************/
  58
  59 ssize_t sys_read(int fd, void *buf, size_t count)
  60 {
  61         ssize_t ret;
  62
  63         do {
  64                 ret = read(fd, buf, count);
  65 #if defined(EWOULDBLOCK)
  66         } while (ret == -1 && (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK));
  67 #else
  68         } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
  69 #endif
  70         return ret;
  71 }
  72
  73 /*******************************************************************
  74 A write wrapper that will deal with EINTR.
  75 ********************************************************************/
  76
  77 ssize_t sys_write(int fd, const void *buf, size_t count)
  78 {
  79         ssize_t ret;
  80
  81         do {
  82                 ret = write(fd, buf, count);
  83 #if defined(EWOULDBLOCK)
  84         } while (ret == -1 && (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK));
  85 #else
  86         } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
  87 #endif
  88         return ret;
  89 }
  90
  91 /*******************************************************************
  92 A writev wrapper that will deal with EINTR.
  93 ********************************************************************/
  94
  95 ssize_t sys_writev(int fd, const struct iovec *iov, int iovcnt)
  96 {
  97         ssize_t ret;
  98
  99 #if 0
 100         /* Try to confuse write_data_iov a bit */
 101         if ((random() % 5) == 0) {
 102                 return sys_write(fd, iov[0].iov_base, iov[0].iov_len);
 103         }
 104         if (iov[0].iov_len > 1) {
 105                 return sys_write(fd, iov[0].iov_base,
 106                                  (random() % (iov[0].iov_len-1)) + 1);
 107         }
 108 #endif
 109
 110         do {
 111                 ret = writev(fd, iov, iovcnt);
 112 #if defined(EWOULDBLOCK)
 113         } while (ret == -1 && (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK));
 114 #else
 115         } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
 116 #endif
 117         return ret;
 118 }
 119
 120 /*******************************************************************
 121 A pread wrapper that will deal with EINTR
 122 ********************************************************************/
 123
 124 #if defined(HAVE_PREAD)
 125 ssize_t sys_pread(int fd, void *buf, size_t count, off_t off)
 126 {
 127         ssize_t ret;
 128
 129         do {
 130                 ret = pread(fd, buf, count, off);
 131         } while (ret == -1 && errno == EINTR);
 132         return ret;
 133 }
 134 #endif
 135
 136 /*******************************************************************
 137 A write wrapper that will deal with EINTR
 138 ********************************************************************/
 139
 140 #if defined(HAVE_PWRITE)
 141 ssize_t sys_pwrite(int fd, const void *buf, size_t count, off_t off)
 142 {
 143         ssize_t ret;
 144
 145         do {
 146                 ret = pwrite(fd, buf, count, off);
 147         } while (ret == -1 && errno == EINTR);
 148         return ret;
 149 }
 150 #endif
 151
 152 /*******************************************************************
 153 A send wrapper that will deal with EINTR or EAGAIN or EWOULDBLOCK.
 154 ********************************************************************/
 155
 156 ssize_t sys_send(int s, const void *msg, size_t len, int flags)
 157 {
 158         ssize_t ret;
 159
 160         do {
 161                 ret = send(s, msg, len, flags);
 162 #if defined(EWOULDBLOCK)
 163         } while (ret == -1 && (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK));
 164 #else
 165         } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
 166 #endif
 167         return ret;
 168 }
 169
 170 /*******************************************************************
 171 A recvfrom wrapper that will deal with EINTR.
 172 ********************************************************************/
 173
 174 ssize_t sys_recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen)
 175 {
 176         ssize_t ret;
 177
 178         do {
 179                 ret = recvfrom(s, buf, len, flags, from, fromlen);
 180 #if defined(EWOULDBLOCK)
 181         } while (ret == -1 && (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK));
 182 #else
 183         } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
 184 #endif
 185         return ret;
 186 }
 187
 188 /*******************************************************************
 189 A fcntl wrapper that will deal with EINTR.
 190 ********************************************************************/
 191
 192 int sys_fcntl_ptr(int fd, int cmd, void *arg)
 193 {
 194         int ret;
 195
 196         do {
 197                 ret = fcntl(fd, cmd, arg);
 198         } while (ret == -1 && errno == EINTR);
 199         return ret;
 200 }
 201
 202 /*******************************************************************
 203 A fcntl wrapper that will deal with EINTR.
 204 ********************************************************************/
 205
 206 int sys_fcntl_long(int fd, int cmd, long arg)
 207 {
 208         int ret;
 209
 210         do {
 211                 ret = fcntl(fd, cmd, arg);
 212         } while (ret == -1 && errno == EINTR);
 213         return ret;
 214 }
 215
 216 /****************************************************************************
 217  Get/Set all the possible time fields from a stat struct as a timespec.
 218 ****************************************************************************/
 219
 220 static struct timespec get_atimespec(const struct stat *pst)
 221 {
 222 #if !defined(HAVE_STAT_HIRES_TIMESTAMPS)
 223         struct timespec ret;
 224
 225         /* Old system - no ns timestamp. */
 226         ret.tv_sec = pst->st_atime;
 227         ret.tv_nsec = 0;
 228         return ret;
 229 #else
 230 #if defined(HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC)
 231         return pst->st_atim;
 232 #elif defined(HAVE_STRUCT_STAT_ST_MTIMENSEC)
 233         struct timespec ret;
 234         ret.tv_sec = pst->st_atime;
 235         ret.tv_nsec = pst->st_atimensec;
 236         return ret;
 237 #elif defined(HAVE_STRUCT_STAT_ST_MTIME_N)
 238         struct timespec ret;
 239         ret.tv_sec = pst->st_atime;
 240         ret.tv_nsec = pst->st_atime_n;
 241         return ret;
 242 #elif defined(HAVE_STRUCT_STAT_ST_UMTIME)
 243         struct timespec ret;
 244         ret.tv_sec = pst->st_atime;
 245         ret.tv_nsec = pst->st_uatime * 1000;
 246         return ret;
 247 #elif defined(HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC)
 248         return pst->st_atimespec;
 249 #else
 250 #error  CONFIGURE_ERROR_IN_DETECTING_TIMESPEC_IN_STAT
 251 #endif
 252 #endif
 253 }
 254
 255 static struct timespec get_mtimespec(const struct stat *pst)
 256 {
 257 #if !defined(HAVE_STAT_HIRES_TIMESTAMPS)
 258         struct timespec ret;
 259
 260         /* Old system - no ns timestamp. */
 261         ret.tv_sec = pst->st_mtime;
 262         ret.tv_nsec = 0;
 263         return ret;
 264 #else
 265 #if defined(HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC)
 266         return pst->st_mtim;
 267 #elif defined(HAVE_STRUCT_STAT_ST_MTIMENSEC)
 268         struct timespec ret;
 269         ret.tv_sec = pst->st_mtime;
 270         ret.tv_nsec = pst->st_mtimensec;
 271         return ret;
 272 #elif defined(HAVE_STRUCT_STAT_ST_MTIME_N)
 273         struct timespec ret;
 274         ret.tv_sec = pst->st_mtime;
 275         ret.tv_nsec = pst->st_mtime_n;
 276         return ret;
 277 #elif defined(HAVE_STRUCT_STAT_ST_UMTIME)
 278         struct timespec ret;
 279         ret.tv_sec = pst->st_mtime;
 280         ret.tv_nsec = pst->st_umtime * 1000;
 281         return ret;
 282 #elif defined(HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC)
 283         return pst->st_mtimespec;
 284 #else
 285 #error  CONFIGURE_ERROR_IN_DETECTING_TIMESPEC_IN_STAT
 286 #endif
 287 #endif
 288 }
 289
 290 static struct timespec get_ctimespec(const struct stat *pst)
 291 {
 292 #if !defined(HAVE_STAT_HIRES_TIMESTAMPS)
 293         struct timespec ret;
 294
 295         /* Old system - no ns timestamp. */
 296         ret.tv_sec = pst->st_ctime;
 297         ret.tv_nsec = 0;
 298         return ret;
 299 #else
 300 #if defined(HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC)
 301         return pst->st_ctim;
 302 #elif defined(HAVE_STRUCT_STAT_ST_MTIMENSEC)
 303         struct timespec ret;
 304         ret.tv_sec = pst->st_ctime;
 305         ret.tv_nsec = pst->st_ctimensec;
 306         return ret;
 307 #elif defined(HAVE_STRUCT_STAT_ST_MTIME_N)
 308         struct timespec ret;
 309         ret.tv_sec = pst->st_ctime;
 310         ret.tv_nsec = pst->st_ctime_n;
 311         return ret;
 312 #elif defined(HAVE_STRUCT_STAT_ST_UMTIME)
 313         struct timespec ret;
 314         ret.tv_sec = pst->st_ctime;
 315         ret.tv_nsec = pst->st_uctime * 1000;
 316         return ret;
 317 #elif defined(HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC)
 318         return pst->st_ctimespec;
 319 #else
 320 #error  CONFIGURE_ERROR_IN_DETECTING_TIMESPEC_IN_STAT
 321 #endif
 322 #endif
 323 }
 324
 325 /****************************************************************************
 326  Return the best approximation to a 'create time' under UNIX from a stat
 327  structure.
 328 ****************************************************************************/
 329
 330 static struct timespec calc_create_time_stat(const struct stat *st)
 331 {
 332         struct timespec ret, ret1;
 333         struct timespec c_time = get_ctimespec(st);
 334         struct timespec m_time = get_mtimespec(st);
 335         struct timespec a_time = get_atimespec(st);
 336
 337         ret = timespec_compare(&c_time, &m_time) < 0 ? c_time : m_time;
 338         ret1 = timespec_compare(&ret, &a_time) < 0 ? ret : a_time;
 339
 340         if(!null_timespec(ret1)) {
 341                 return ret1;
 342         }
 343
 344         /*
 345          * One of ctime, mtime or atime was zero (probably atime).
 346          * Just return MIN(ctime, mtime).
 347          */
 348         return ret;
 349 }
 350
 351 /****************************************************************************
 352  Return the best approximation to a 'create time' under UNIX from a stat_ex
 353  structure.
 354 ****************************************************************************/
 355
 356 static struct timespec calc_create_time_stat_ex(const struct stat_ex *st)
 357 {
 358         struct timespec ret, ret1;
 359         struct timespec c_time = st->st_ex_ctime;
 360         struct timespec m_time = st->st_ex_mtime;
 361         struct timespec a_time = st->st_ex_atime;
 362
 363         ret = timespec_compare(&c_time, &m_time) < 0 ? c_time : m_time;
 364         ret1 = timespec_compare(&ret, &a_time) < 0 ? ret : a_time;
 365
 366         if(!null_timespec(ret1)) {
 367                 return ret1;
 368         }
 369
 370         /*
 371          * One of ctime, mtime or atime was zero (probably atime).
 372          * Just return MIN(ctime, mtime).
 373          */
 374         return ret;
 375 }
 376
 377 /****************************************************************************
 378  Return the 'create time' from a stat struct if it exists (birthtime) or else
 379  use the best approximation.
 380 ****************************************************************************/
 381
 382 static void make_create_timespec(const struct stat *pst, struct stat_ex *dst,
 383                                  bool fake_dir_create_times)
 384 {
 385         if (S_ISDIR(pst->st_mode) && fake_dir_create_times) {
 386                 dst->st_ex_btime.tv_sec = 315493200L;          /* 1/1/1980 */
 387                 dst->st_ex_btime.tv_nsec = 0;
 388         }
 389
 390         dst->st_ex_calculated_birthtime = false;
 391
 392 #if defined(HAVE_STRUCT_STAT_ST_BIRTHTIMESPEC_TV_NSEC)
 393         dst->st_ex_btime = pst->st_birthtimespec;
 394 #elif defined(HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC)
 395         dst->st_ex_btime.tv_sec = pst->st_birthtime;
 396         dst->st_ex_btime.tv_nsec = pst->st_birthtimenspec;
 397 #elif defined(HAVE_STRUCT_STAT_ST_BIRTHTIME)
 398         dst->st_ex_btime.tv_sec = pst->st_birthtime;
 399         dst->st_ex_btime.tv_nsec = 0;
 400 #else
 401         dst->st_ex_btime = calc_create_time_stat(pst);
 402         dst->st_ex_calculated_birthtime = true;
 403 #endif
 404
 405         /* Deal with systems that don't initialize birthtime correctly.
 406          * Pointed out by SATOH Fumiyasu <fumiyas@osstech.jp>.
 407          */
 408         if (null_timespec(dst->st_ex_btime)) {
 409                 dst->st_ex_btime = calc_create_time_stat(pst);
 410                 dst->st_ex_calculated_birthtime = true;
 411         }
 412 }
 413
 414 /****************************************************************************
 415  If we update a timestamp in a stat_ex struct we may have to recalculate
 416  the birthtime. For now only implement this for write time, but we may
 417  also need to do it for atime and ctime. JRA.
 418 ****************************************************************************/
 419
 420 void update_stat_ex_mtime(struct stat_ex *dst,
 421                                 struct timespec write_ts)
 422 {
 423         dst->st_ex_mtime = write_ts;
 424
 425         /* We may have to recalculate btime. */
 426         if (dst->st_ex_calculated_birthtime) {
 427                 dst->st_ex_btime = calc_create_time_stat_ex(dst);
 428         }
 429 }
 430
 431 void update_stat_ex_create_time(struct stat_ex *dst,
 432                                 struct timespec create_time)
 433 {
 434         dst->st_ex_btime = create_time;
 435         dst->st_ex_calculated_birthtime = false;
 436 }
 437
 438 void init_stat_ex_from_stat (struct stat_ex *dst,
 439                             const struct stat *src,
 440                             bool fake_dir_create_times)
 441 {
 442         dst->st_ex_dev = src->st_dev;
 443         dst->st_ex_ino = src->st_ino;
 444         dst->st_ex_mode = src->st_mode;
 445         dst->st_ex_nlink = src->st_nlink;
 446         dst->st_ex_uid = src->st_uid;
 447         dst->st_ex_gid = src->st_gid;
 448         dst->st_ex_rdev = src->st_rdev;
 449         dst->st_ex_size = src->st_size;
 450         dst->st_ex_atime = get_atimespec(src);
 451         dst->st_ex_mtime = get_mtimespec(src);
 452         dst->st_ex_ctime = get_ctimespec(src);
 453         make_create_timespec(src, dst, fake_dir_create_times);
 454 #ifdef HAVE_STAT_ST_BLKSIZE
 455         dst->st_ex_blksize = src->st_blksize;
 456 #else
 457         dst->st_ex_blksize = STAT_ST_BLOCKSIZE;
 458 #endif
 459
 460 #ifdef HAVE_STAT_ST_BLOCKS
 461         dst->st_ex_blocks = src->st_blocks;
 462 #else
 463         dst->st_ex_blocks = src->st_size / dst->st_ex_blksize + 1;
 464 #endif
 465
 466 #ifdef HAVE_STAT_ST_FLAGS
 467         dst->st_ex_flags = src->st_flags;
 468 #else
 469         dst->st_ex_flags = 0;
 470 #endif
 471 }
 472
 473 /*******************************************************************
 474 A stat() wrapper.
 475 ********************************************************************/
 476
 477 int sys_stat(const char *fname, SMB_STRUCT_STAT *sbuf,
 478              bool fake_dir_create_times)
 479 {
 480         int ret;
 481         struct stat statbuf;
 482         ret = stat(fname, &statbuf);
 483         if (ret == 0) {
 484                 /* we always want directories to appear zero size */
 485                 if (S_ISDIR(statbuf.st_mode)) {
 486                         statbuf.st_size = 0;
 487                 }
 488                 init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
 489         }
 490         return ret;
 491 }
 492
 493 /*******************************************************************
 494  An fstat() wrapper.
 495 ********************************************************************/
 496
 497 int sys_fstat(int fd, SMB_STRUCT_STAT *sbuf, bool fake_dir_create_times)
 498 {
 499         int ret;
 500         struct stat statbuf;
 501         ret = fstat(fd, &statbuf);
 502         if (ret == 0) {
 503                 /* we always want directories to appear zero size */
 504                 if (S_ISDIR(statbuf.st_mode)) {
 505                         statbuf.st_size = 0;
 506                 }
 507                 init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
 508         }
 509         return ret;
 510 }
 511
 512 /*******************************************************************
 513  An lstat() wrapper.
 514 ********************************************************************/
 515
 516 int sys_lstat(const char *fname,SMB_STRUCT_STAT *sbuf,
 517               bool fake_dir_create_times)
 518 {
 519         int ret;
 520         struct stat statbuf;
 521         ret = lstat(fname, &statbuf);
 522         if (ret == 0) {
 523                 /* we always want directories to appear zero size */
 524                 if (S_ISDIR(statbuf.st_mode)) {
 525                         statbuf.st_size = 0;
 526                 }
 527                 init_stat_ex_from_stat(sbuf, &statbuf, fake_dir_create_times);
 528         }
 529         return ret;
 530 }
 531
 532 /*******************************************************************
 533  An posix_fallocate() wrapper.
 534 ********************************************************************/
 535 int sys_posix_fallocate(int fd, off_t offset, off_t len)
 536 {
 537 #if defined(HAVE_POSIX_FALLOCATE) && !defined(HAVE_BROKEN_POSIX_FALLOCATE)
 538         return posix_fallocate(fd, offset, len);
 539 #elif defined(F_RESVSP64)
 540         /* this handles XFS on IRIX */
 541         struct flock64 fl;
 542         off_t new_len = offset + len;
 543         int ret;
 544         struct stat64 sbuf;
 545
 546         /* unlikely to get a too large file on a 64bit system but ... */
 547         if (new_len < 0)
 548                 return EFBIG;
 549
 550         fl.l_whence = SEEK_SET;
 551         fl.l_start = offset;
 552         fl.l_len = len;
 553
 554         ret=fcntl(fd, F_RESVSP64, &fl);
 555
 556         if (ret != 0)
 557                 return errno;
 558
 559         /* Make sure the file gets enlarged after we allocated space: */
 560         fstat64(fd, &sbuf);
 561         if (new_len > sbuf.st_size)
 562                 ftruncate64(fd, new_len);
 563         return 0;
 564 #else
 565         return ENOSYS;
 566 #endif
 567 }
 568
 569 /*******************************************************************
 570  An fallocate() function that matches the semantics of the Linux one.
 571 ********************************************************************/
 572
 573 #ifdef HAVE_LINUX_FALLOC_H
 574 #include <linux/falloc.h>
 575 #endif
 576
 577 int sys_fallocate(int fd, enum vfs_fallocate_mode mode, off_t offset, off_t len)
 578 {
 579 #if defined(HAVE_LINUX_FALLOCATE64) || defined(HAVE_LINUX_FALLOCATE)
 580         int lmode;
 581         switch (mode) {
 582         case VFS_FALLOCATE_EXTEND_SIZE:
 583                 lmode = 0;
 584                 break;
 585         case VFS_FALLOCATE_KEEP_SIZE:
 586                 lmode = FALLOC_FL_KEEP_SIZE;
 587                 break;
 588         default:
 589                 errno = EINVAL;
 590                 return -1;
 591         }
 592 #if defined(HAVE_LINUX_FALLOCATE)
 593         return fallocate(fd, lmode, offset, len);
 594 #endif
 595 #else
 596         /* TODO - plumb in fallocate from other filesysetms like VXFS etc. JRA. */
 597         errno = ENOSYS;
 598         return -1;
 599 #endif
 600 }
 601
 602 #if HAVE_KERNEL_SHARE_MODES
 603 #ifndef LOCK_MAND
 604 #define LOCK_MAND       32      /* This is a mandatory flock */
 605 #define LOCK_READ       64      /* ... Which allows concurrent read operations */
 606 #define LOCK_WRITE      128     /* ... Which allows concurrent write operations */
 607 #define LOCK_RW         192     /* ... Which allows concurrent read & write ops */
 608 #endif
 609 #endif
 610
 611 /*******************************************************************
 612  A flock() wrapper that will perform the kernel flock.
 613 ********************************************************************/
 614
 615 void kernel_flock(int fd, uint32 share_mode, uint32 access_mask)
 616 {
 617 #if HAVE_KERNEL_SHARE_MODES
 618         int kernel_mode = 0;
 619         if (share_mode == FILE_SHARE_WRITE) {
 620                 kernel_mode = LOCK_MAND|LOCK_WRITE;
 621         } else if (share_mode == FILE_SHARE_READ) {
 622                 kernel_mode = LOCK_MAND|LOCK_READ;
 623         } else if (share_mode == FILE_SHARE_NONE) {
 624                 kernel_mode = LOCK_MAND;
 625         }
 626         if (kernel_mode) {
 627                 flock(fd, kernel_mode);
 628         }
 629 #endif
 630         ;
 631 }
 632
 633
 634
 635 /*******************************************************************
 636  An fdopendir wrapper.
 637  Ugly hack - we need dirfd for this to work correctly in the
 638  calling code.. JRA.
 639 ********************************************************************/
 640
 641 DIR *sys_fdopendir(int fd)
 642 {
 643 #if defined(HAVE_FDOPENDIR) && defined(HAVE_DIRFD)
 644         return fdopendir(fd);
 645 #else
 646         errno = ENOSYS;
 647         return NULL;
 648 #endif
 649 }
 650
 651 /*******************************************************************
 652  An mknod() wrapper.
 653 ********************************************************************/
 654
 655 int sys_mknod(const char *path, mode_t mode, SMB_DEV_T dev)
 656 {
 657 #if defined(HAVE_MKNOD)
 658         return mknod(path, mode, dev);
 659 #else
 660         /* No mknod system call. */
 661         errno = ENOSYS;
 662         return -1;
 663 #endif
 664 }
 665
 666 /*******************************************************************
 667 The wait() calls vary between systems
 668 ********************************************************************/
 669
 670 int sys_waitpid(pid_t pid,int *status,int options)
 671 {
 672 #ifdef HAVE_WAITPID
 673         return waitpid(pid,status,options);
 674 #else /* HAVE_WAITPID */
 675         return wait4(pid, status, options, NULL);
 676 #endif /* HAVE_WAITPID */
 677 }
 678
 679 /*******************************************************************
 680  System wrapper for getwd. Always returns MALLOC'ed memory, or NULL
 681  on error (malloc fail usually).
 682 ********************************************************************/
 683
 684 char *sys_getwd(void)
 685 {
 686 #ifdef GETCWD_TAKES_NULL
 687         return getcwd(NULL, 0);
 688 #elif HAVE_GETCWD
 689         char *wd = NULL, *s = NULL;
 690         size_t allocated = PATH_MAX;
 691
 692         while (1) {
 693                 s = SMB_REALLOC_ARRAY(s, char, allocated);
 694                 if (s == NULL) {
 695                         return NULL;
 696                 }
 697                 wd = getcwd(s, allocated);
 698                 if (wd) {
 699                         break;
 700                 }
 701                 if (errno != ERANGE) {
 702                         SAFE_FREE(s);
 703                         break;
 704                 }
 705                 allocated *= 2;
 706                 if (allocated < PATH_MAX) {
 707                         SAFE_FREE(s);
 708                         break;
 709                 }
 710         }
 711         return wd;
 712 #else
 713         char *s = SMB_MALLOC_ARRAY(char, PATH_MAX);
 714         if (s == NULL) {
 715                 return NULL;
 716         }
 717         return getwd(s);
 718 #endif
 719 }
 720
 721 #if defined(HAVE_POSIX_CAPABILITIES)
 722
 723 /**************************************************************************
 724  Try and abstract process capabilities (for systems that have them).
 725 ****************************************************************************/
 726
 727 /* Set the POSIX capabilities needed for the given purpose into the effective
 728  * capability set of the current process. Make sure they are always removed
 729  * from the inheritable set, because there is no circumstance in which our
 730  * children should inherit our elevated privileges.
 731  */
 732 static bool set_process_capability(enum smbd_capability capability,
 733                                    bool enable)
 734 {
 735         cap_value_t cap_vals[2] = {0};
 736         int num_cap_vals = 0;
 737
 738         cap_t cap;
 739
 740 #if defined(HAVE_PRCTL) && defined(PR_GET_KEEPCAPS) && defined(PR_SET_KEEPCAPS)
 741         /* On Linux, make sure that any capabilities we grab are sticky
 742          * across UID changes. We expect that this would allow us to keep both
 743          * the effective and permitted capability sets, but as of circa 2.6.16,
 744          * only the permitted set is kept. It is a bug (which we work around)
 745          * that the effective set is lost, but we still require the effective
 746          * set to be kept.
 747          */
 748         if (!prctl(PR_GET_KEEPCAPS)) {
 749                 prctl(PR_SET_KEEPCAPS, 1);
 750         }
 751 #endif
 752
 753         cap = cap_get_proc();
 754         if (cap == NULL) {
 755                 DEBUG(0,("set_process_capability: cap_get_proc failed: %s\n",
 756                         strerror(errno)));
 757                 return False;
 758         }
 759
 760         switch (capability) {
 761                 case KERNEL_OPLOCK_CAPABILITY:
 762 #ifdef CAP_NETWORK_MGT
 763                         /* IRIX has CAP_NETWORK_MGT for oplocks. */
 764                         cap_vals[num_cap_vals++] = CAP_NETWORK_MGT;
 765 #endif
 766                         break;
 767                 case DMAPI_ACCESS_CAPABILITY:
 768 #ifdef CAP_DEVICE_MGT
 769                         /* IRIX has CAP_DEVICE_MGT for DMAPI access. */
 770                         cap_vals[num_cap_vals++] = CAP_DEVICE_MGT;
 771 #elif CAP_MKNOD
 772                         /* Linux has CAP_MKNOD for DMAPI access. */
 773                         cap_vals[num_cap_vals++] = CAP_MKNOD;
 774 #endif
 775                         break;
 776                 case LEASE_CAPABILITY:
 777 #ifdef CAP_LEASE
 778                         cap_vals[num_cap_vals++] = CAP_LEASE;
 779 #endif
 780                         break;
 781         }
 782
 783         SMB_ASSERT(num_cap_vals <= ARRAY_SIZE(cap_vals));
 784
 785         if (num_cap_vals == 0) {
 786                 cap_free(cap);
 787                 return True;
 788         }
 789
 790         cap_set_flag(cap, CAP_EFFECTIVE, num_cap_vals, cap_vals,
 791                 enable ? CAP_SET : CAP_CLEAR);
 792
 793         /* We never want to pass capabilities down to our children, so make
 794          * sure they are not inherited.
 795          */
 796         cap_set_flag(cap, CAP_INHERITABLE, num_cap_vals, cap_vals, CAP_CLEAR);
 797
 798         if (cap_set_proc(cap) == -1) {
 799                 DEBUG(0, ("set_process_capability: cap_set_proc failed: %s\n",
 800                         strerror(errno)));
 801                 cap_free(cap);
 802                 return False;
 803         }
 804
 805         cap_free(cap);
 806         return True;
 807 }
 808
 809 #endif /* HAVE_POSIX_CAPABILITIES */
 810
 811 /****************************************************************************
 812  Gain the oplock capability from the kernel if possible.
 813 ****************************************************************************/
 814
 815 void set_effective_capability(enum smbd_capability capability)
 816 {
 817 #if defined(HAVE_POSIX_CAPABILITIES)
 818         set_process_capability(capability, True);
 819 #endif /* HAVE_POSIX_CAPABILITIES */
 820 }
 821
 822 void drop_effective_capability(enum smbd_capability capability)
 823 {
 824 #if defined(HAVE_POSIX_CAPABILITIES)
 825         set_process_capability(capability, False);
 826 #endif /* HAVE_POSIX_CAPABILITIES */
 827 }
 828
 829 /**************************************************************************
 830  Wrapper for random().
 831 ****************************************************************************/
 832
 833 long sys_random(void)
 834 {
 835 #if defined(HAVE_RANDOM)
 836         return (long)random();
 837 #elif defined(HAVE_RAND)
 838         return (long)rand();
 839 #else
 840         DEBUG(0,("Error - no random function available !\n"));
 841         exit(1);
 842 #endif
 843 }
 844
 845 /**************************************************************************
 846  Wrapper for srandom().
 847 ****************************************************************************/
 848
 849 void sys_srandom(unsigned int seed)
 850 {
 851 #if defined(HAVE_SRANDOM)
 852         srandom(seed);
 853 #elif defined(HAVE_SRAND)
 854         srand(seed);
 855 #else
 856         DEBUG(0,("Error - no srandom function available !\n"));
 857         exit(1);
 858 #endif
 859 }
 860
 861 #ifndef NGROUPS_MAX
 862 #define NGROUPS_MAX 32 /* Guess... */
 863 #endif
 864
 865 /**************************************************************************
 866  Returns equivalent to NGROUPS_MAX - using sysconf if needed.
 867 ****************************************************************************/
 868
 869 int groups_max(void)
 870 {
 871 #if defined(SYSCONF_SC_NGROUPS_MAX)
 872         int ret = sysconf(_SC_NGROUPS_MAX);
 873         return (ret == -1) ? NGROUPS_MAX : ret;
 874 #else
 875         return NGROUPS_MAX;
 876 #endif
 877 }
 878
 879 /**************************************************************************
 880  Wrap setgroups and getgroups for systems that declare getgroups() as
 881  returning an array of gid_t, but actuall return an array of int.
 882 ****************************************************************************/
 883
 884 #if defined(HAVE_BROKEN_GETGROUPS)
 885
 886 #ifdef HAVE_BROKEN_GETGROUPS
 887 #define GID_T int
 888 #else
 889 #define GID_T gid_t
 890 #endif
 891
 892 static int sys_broken_getgroups(int setlen, gid_t *gidset)
 893 {
 894         GID_T gid;
 895         GID_T *group_list;
 896         int i, ngroups;
 897
 898         if(setlen == 0) {
 899                 return getgroups(setlen, &gid);
 900         }
 901
 902         /*
 903          * Broken case. We need to allocate a
 904          * GID_T array of size setlen.
 905          */
 906
 907         if(setlen < 0) {
 908                 errno = EINVAL;
 909                 return -1;
 910         }
 911
 912         if (setlen == 0)
 913                 setlen = groups_max();
 914
 915         if((group_list = SMB_MALLOC_ARRAY(GID_T, setlen)) == NULL) {
 916                 DEBUG(0,("sys_getgroups: Malloc fail.\n"));
 917                 return -1;
 918         }
 919
 920         if((ngroups = getgroups(setlen, group_list)) < 0) {
 921                 int saved_errno = errno;
 922                 SAFE_FREE(group_list);
 923                 errno = saved_errno;
 924                 return -1;
 925         }
 926
 927         for(i = 0; i < ngroups; i++)
 928                 gidset[i] = (gid_t)group_list[i];
 929
 930         SAFE_FREE(group_list);
 931         return ngroups;
 932 }
 933
 934 static int sys_broken_setgroups(int setlen, gid_t *gidset)
 935 {
 936         GID_T *group_list;
 937         int i ;
 938
 939         if (setlen == 0)
 940                 return 0 ;
 941
 942         if (setlen < 0 || setlen > groups_max()) {
 943                 errno = EINVAL;
 944                 return -1;
 945         }
 946
 947         /*
 948          * Broken case. We need to allocate a
 949          * GID_T array of size setlen.
 950          */
 951
 952         if((group_list = SMB_MALLOC_ARRAY(GID_T, setlen)) == NULL) {
 953                 DEBUG(0,("sys_setgroups: Malloc fail.\n"));
 954                 return -1;
 955         }
 956
 957         for(i = 0; i < setlen; i++)
 958                 group_list[i] = (GID_T) gidset[i];
 959
 960         if(samba_setgroups(setlen, group_list) != 0) {
 961                 int saved_errno = errno;
 962                 SAFE_FREE(group_list);
 963                 errno = saved_errno;
 964                 return -1;
 965         }
 966
 967         SAFE_FREE(group_list);
 968         return 0 ;
 969 }
 970
 971 #endif /* HAVE_BROKEN_GETGROUPS */
 972
 973 /* This is a list of systems that require the first GID passed to setgroups(2)
 974  * to be the effective GID. If your system is one of these, add it here.
 975  */
 976 #if defined (FREEBSD) || defined (DARWINOS)
 977 #define USE_BSD_SETGROUPS
 978 #endif
 979
 980 #if defined(USE_BSD_SETGROUPS)
 981 /* Depending on the particular BSD implementation, the first GID that is
 982  * passed to setgroups(2) will either be ignored or will set the credential's
 983  * effective GID. In either case, the right thing to do is to guarantee that
 984  * gidset[0] is the effective GID.
 985  */
 986 static int sys_bsd_setgroups(gid_t primary_gid, int setlen, const gid_t *gidset)
 987 {
 988         gid_t *new_gidset = NULL;
 989         int max;
 990         int ret;
 991
 992         /* setgroups(2) will fail with EINVAL if we pass too many groups. */
 993         max = groups_max();
 994
 995         /* No group list, just make sure we are setting the efective GID. */
 996         if (setlen == 0) {
 997                 return samba_setgroups(1, &primary_gid);
 998         }
 999
1000         /* If the primary gid is not the first array element, grow the array
1001          * and insert it at the front.
1002          */
1003         if (gidset[0] != primary_gid) {
1004                 new_gidset = SMB_MALLOC_ARRAY(gid_t, setlen + 1);
1005                 if (new_gidset == NULL) {
1006                         return -1;
1007                 }
1008
1009                 memcpy(new_gidset + 1, gidset, (setlen * sizeof(gid_t)));
1010                 new_gidset[0] = primary_gid;
1011                 setlen++;
1012         }
1013
1014         if (setlen > max) {
1015                 DEBUG(3, ("forced to truncate group list from %d to %d\n",
1016                         setlen, max));
1017                 setlen = max;
1018         }
1019
1020 #if defined(HAVE_BROKEN_GETGROUPS)
1021         ret = sys_broken_setgroups(setlen, new_gidset ? new_gidset : gidset);
1022 #else
1023         ret = samba_setgroups(setlen, new_gidset ? new_gidset : gidset);
1024 #endif
1025
1026         if (new_gidset) {
1027                 int errsav = errno;
1028                 SAFE_FREE(new_gidset);
1029                 errno = errsav;
1030         }
1031
1032         return ret;
1033 }
1034
1035 #endif /* USE_BSD_SETGROUPS */
1036
1037 /**************************************************************************
1038  Wrapper for getgroups. Deals with broken (int) case.
1039 ****************************************************************************/
1040
1041 int sys_getgroups(int setlen, gid_t *gidset)
1042 {
1043 #if defined(HAVE_BROKEN_GETGROUPS)
1044         return sys_broken_getgroups(setlen, gidset);
1045 #else
1046         return getgroups(setlen, gidset);
1047 #endif
1048 }
1049
1050 /**************************************************************************
1051  Wrapper for setgroups. Deals with broken (int) case and BSD case.
1052 ****************************************************************************/
1053
1054 int sys_setgroups(gid_t UNUSED(primary_gid), int setlen, gid_t *gidset)
1055 {
1056 #if !defined(HAVE_SETGROUPS)
1057         errno = ENOSYS;
1058         return -1;
1059 #endif /* HAVE_SETGROUPS */
1060
1061 #if defined(USE_BSD_SETGROUPS)
1062         return sys_bsd_setgroups(primary_gid, setlen, gidset);
1063 #elif defined(HAVE_BROKEN_GETGROUPS)
1064         return sys_broken_setgroups(setlen, gidset);
1065 #else
1066         return samba_setgroups(setlen, gidset);
1067 #endif
1068 }
1069
1070 /**************************************************************************
1071  Extract a command into an arg list.
1072 ****************************************************************************/
1073
1074 static char **extract_args(TALLOC_CTX *mem_ctx, const char *command)
1075 {
1076         char *trunc_cmd;
1077         char *saveptr;
1078         char *ptr;
1079         int argcl;
1080         char **argl = NULL;
1081         int i;
1082
1083         if (!(trunc_cmd = talloc_strdup(mem_ctx, command))) {
1084                 DEBUG(0, ("talloc failed\n"));
1085                 goto nomem;
1086         }
1087
1088         if(!(ptr = strtok_r(trunc_cmd, " \t", &saveptr))) {
1089                 TALLOC_FREE(trunc_cmd);
1090                 errno = EINVAL;
1091                 return NULL;
1092         }
1093
1094         /*
1095          * Count the args.
1096          */
1097
1098         for( argcl = 1; ptr; ptr = strtok_r(NULL, " \t", &saveptr))
1099                 argcl++;
1100
1101         TALLOC_FREE(trunc_cmd);
1102
1103         if (!(argl = talloc_array(mem_ctx, char *, argcl + 1))) {
1104                 goto nomem;
1105         }
1106
1107         /*
1108          * Now do the extraction.
1109          */
1110
1111         if (!(trunc_cmd = talloc_strdup(mem_ctx, command))) {
1112                 goto nomem;
1113         }
1114
1115         ptr = strtok_r(trunc_cmd, " \t", &saveptr);
1116         i = 0;
1117
1118         if (!(argl[i++] = talloc_strdup(argl, ptr))) {
1119                 goto nomem;
1120         }
1121
1122         while((ptr = strtok_r(NULL, " \t", &saveptr)) != NULL) {
1123
1124                 if (!(argl[i++] = talloc_strdup(argl, ptr))) {
1125                         goto nomem;
1126                 }
1127         }
1128
1129         argl[i++] = NULL;
1130         TALLOC_FREE(trunc_cmd);
1131         return argl;
1132
1133  nomem:
1134         DEBUG(0, ("talloc failed\n"));
1135         TALLOC_FREE(trunc_cmd);
1136         TALLOC_FREE(argl);
1137         errno = ENOMEM;
1138         return NULL;
1139 }
1140
1141 /**************************************************************************
1142  Wrapper for popen. Safer as it doesn't search a path.
1143  Modified from the glibc sources.
1144  modified by tridge to return a file descriptor. We must kick our FILE* habit
1145 ****************************************************************************/
1146
1147 typedef struct _popen_list
1148 {
1149         int fd;
1150         pid_t child_pid;
1151         struct _popen_list *next;
1152 } popen_list;
1153
1154 static popen_list *popen_chain;
1155
1156 int sys_popen(const char *command)
1157 {
1158         int parent_end, child_end;
1159         int pipe_fds[2];
1160         popen_list *entry = NULL;
1161         char **argl = NULL;
1162         int ret;
1163
1164         if (pipe(pipe_fds) < 0)
1165                 return -1;
1166
1167         parent_end = pipe_fds[0];
1168         child_end = pipe_fds[1];
1169
1170         if (!*command) {
1171                 errno = EINVAL;
1172                 goto err_exit;
1173         }
1174
1175         if((entry = SMB_MALLOC_P(popen_list)) == NULL)
1176                 goto err_exit;
1177
1178         ZERO_STRUCTP(entry);
1179
1180         /*
1181          * Extract the command and args into a NULL terminated array.
1182          */
1183
1184         if(!(argl = extract_args(NULL, command)))
1185                 goto err_exit;
1186
1187         entry->child_pid = fork();
1188
1189         if (entry->child_pid == -1) {
1190                 goto err_exit;
1191         }
1192
1193         if (entry->child_pid == 0) {
1194
1195                 /*
1196                  * Child !
1197                  */
1198
1199                 int child_std_end = STDOUT_FILENO;
1200                 popen_list *p;
1201
1202                 close(parent_end);
1203                 if (child_end != child_std_end) {
1204                         dup2 (child_end, child_std_end);
1205                         close (child_end);
1206                 }
1207
1208                 /*
1209                  * POSIX.2:  "popen() shall ensure that any streams from previous
1210                  * popen() calls that remain open in the parent process are closed
1211                  * in the new child process."
1212                  */
1213
1214                 for (p = popen_chain; p; p = p->next)
1215                         close(p->fd);
1216
1217                 ret = execv(argl[0], argl);
1218                 if (ret == -1) {
1219                         DEBUG(0, ("sys_popen: ERROR executing dfree command "
1220                                   "'%s': %s\n", command, strerror(errno)));
1221                 }
1222                 _exit (127);
1223         }
1224
1225         /*
1226          * Parent.
1227          */
1228
1229         close (child_end);
1230         TALLOC_FREE(argl);
1231
1232         /* Link into popen_chain. */
1233         entry->next = popen_chain;
1234         popen_chain = entry;
1235         entry->fd = parent_end;
1236
1237         return entry->fd;
1238
1239 err_exit:
1240
1241         SAFE_FREE(entry);
1242         TALLOC_FREE(argl);
1243         close(pipe_fds[0]);
1244         close(pipe_fds[1]);
1245         return -1;
1246 }
1247
1248 /**************************************************************************
1249  Wrapper for pclose. Modified from the glibc sources.
1250 ****************************************************************************/
1251
1252 int sys_pclose(int fd)
1253 {
1254         int wstatus;
1255         popen_list **ptr = &popen_chain;
1256         popen_list *entry = NULL;
1257         pid_t wait_pid;
1258         int status = -1;
1259
1260         /* Unlink from popen_chain. */
1261         for ( ; *ptr != NULL; ptr = &(*ptr)->next) {
1262                 if ((*ptr)->fd == fd) {
1263                         entry = *ptr;
1264                         *ptr = (*ptr)->next;
1265                         status = 0;
1266                         break;
1267                 }
1268         }
1269
1270         if (status < 0 || close(entry->fd) < 0)
1271                 return -1;
1272
1273         /*
1274          * As Samba is catching and eating child process
1275          * exits we don't really care about the child exit
1276          * code, a -1 with errno = ECHILD will do fine for us.
1277          */
1278
1279         do {
1280                 wait_pid = sys_waitpid (entry->child_pid, &wstatus, 0);
1281         } while (wait_pid == -1 && errno == EINTR);
1282
1283         SAFE_FREE(entry);
1284
1285         if (wait_pid == -1)
1286                 return -1;
1287         return wstatus;
1288 }
1289
1290 /**************************************************************************
1291  Wrapper for Admin Logs.
1292 ****************************************************************************/
1293
1294  void sys_adminlog(int priority, const char *format_str, ...)
1295 {
1296         va_list ap;
1297         int ret;
1298         char *msgbuf = NULL;
1299
1300         va_start( ap, format_str );
1301         ret = vasprintf( &msgbuf, format_str, ap );
1302         va_end( ap );
1303
1304         if (ret == -1)
1305                 return;
1306
1307 #if defined(HAVE_SYSLOG)
1308         syslog( priority, "%s", msgbuf );
1309 #else
1310         DEBUG(0,("%s", msgbuf ));
1311 #endif
1312         SAFE_FREE(msgbuf);
1313 }
1314
1315 /****************************************************************************
1316  Return the major devicenumber for UNIX extensions.
1317 ****************************************************************************/
1318
1319 uint32 unix_dev_major(SMB_DEV_T dev)
1320 {
1321 #if defined(HAVE_DEVICE_MAJOR_FN)
1322         return (uint32)major(dev);
1323 #else
1324         return (uint32)(dev >> 8);
1325 #endif
1326 }
1327
1328 /****************************************************************************
1329  Return the minor devicenumber for UNIX extensions.
1330 ****************************************************************************/
1331
1332 uint32 unix_dev_minor(SMB_DEV_T dev)
1333 {
1334 #if defined(HAVE_DEVICE_MINOR_FN)
1335         return (uint32)minor(dev);
1336 #else
1337         return (uint32)(dev & 0xff);
1338 #endif
1339 }
1340
1341 #if 0
1342 /*******************************************************************
1343  Return the number of CPUs.
1344 ********************************************************************/
1345
1346 int sys_get_number_of_cores(void)
1347 {
1348         int ret = -1;
1349
1350 #if defined(HAVE_SYSCONF)
1351 #if defined(_SC_NPROCESSORS_ONLN)
1352         ret = (int)sysconf(_SC_NPROCESSORS_ONLN);
1353 #endif
1354 #if defined(_SC_NPROCESSORS_CONF)
1355         if (ret < 1) {
1356                 ret = (int)sysconf(_SC_NPROCESSORS_CONF);
1357         }
1358 #endif
1359 #elif defined(HAVE_SYSCTL) && defined(CTL_HW)
1360         int name[2];
1361         unsigned int len = sizeof(ret);
1362
1363         name[0] = CTL_HW;
1364 #if defined(HW_AVAILCPU)
1365         name[1] = HW_AVAILCPU;
1366
1367         if (sysctl(name, 2, &ret, &len, NULL, 0) == -1) {
1368                 ret = -1;
1369         }
1370 #endif
1371 #if defined(HW_NCPU)
1372         if(ret < 1) {
1373                 name[0] = CTL_HW;
1374                 name[1] = HW_NCPU;
1375                 if (sysctl(nm, 2, &count, &len, NULL, 0) == -1) {
1376                         ret = -1;
1377                 }
1378         }
1379 #endif
1380 #endif
1381         if (ret < 1) {
1382                 ret = 1;
1383         }
1384         return ret;
1385 }
1386 #endif