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- /*
- * Copyright (c) 2004-2005 Todd C. Miller <Todd.Miller@courtesan.com>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
- #include "includes.h"
-
- #if !defined(HAVE_CLOSEFROM) || defined(BROKEN_CLOSEFROM)
-
- #include <sys/types.h>
- #include <unistd.h>
- #include <stdio.h>
- #ifdef HAVE_FCNTL_H
- # include <fcntl.h>
- #endif
- #include <limits.h>
- #include <stdlib.h>
- #include <stddef.h>
- #include <string.h>
- #ifdef HAVE_DIRENT_H
- # include <dirent.h>
- # define NAMLEN(dirent) strlen((dirent)->d_name)
- #else
- # define dirent direct
- # define NAMLEN(dirent) (dirent)->d_namlen
- # ifdef HAVE_SYS_NDIR_H
- # include <sys/ndir.h>
- # endif
- # ifdef HAVE_SYS_DIR_H
- # include <sys/dir.h>
- # endif
- # ifdef HAVE_NDIR_H
- # include <ndir.h>
- # endif
- #endif
- #if defined(HAVE_LIBPROC_H)
- # include <libproc.h>
- #endif
-
- #ifndef OPEN_MAX
- # define OPEN_MAX 256
- #endif
-
- #if 0
- __unused static const char rcsid[] = "$Sudo: closefrom.c,v 1.11 2006/08/17 15:26:54 millert Exp $";
- #endif /* lint */
-
- #ifndef HAVE_FCNTL_CLOSEM
- /*
- * Close all file descriptors greater than or equal to lowfd.
- */
- static void
- closefrom_fallback(int lowfd)
- {
- long fd, maxfd;
-
- /*
- * Fall back on sysconf() or getdtablesize(). We avoid checking
- * resource limits since it is possible to open a file descriptor
- * and then drop the rlimit such that it is below the open fd.
- */
- #ifdef HAVE_SYSCONF
- maxfd = sysconf(_SC_OPEN_MAX);
- #else
- maxfd = getdtablesize();
- #endif /* HAVE_SYSCONF */
- if (maxfd < 0)
- maxfd = OPEN_MAX;
-
- for (fd = lowfd; fd < maxfd; fd++)
- (void) close((int) fd);
- }
- #endif /* HAVE_FCNTL_CLOSEM */
-
- #ifdef HAVE_FCNTL_CLOSEM
- void
- closefrom(int lowfd)
- {
- (void) fcntl(lowfd, F_CLOSEM, 0);
- }
- #elif defined(HAVE_LIBPROC_H) && defined(HAVE_PROC_PIDINFO)
- void
- closefrom(int lowfd)
- {
- int i, r, sz;
- pid_t pid = getpid();
- struct proc_fdinfo *fdinfo_buf = NULL;
-
- sz = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, NULL, 0);
- if (sz == 0)
- return; /* no fds, really? */
- else if (sz == -1)
- goto fallback;
- if ((fdinfo_buf = malloc(sz)) == NULL)
- goto fallback;
- r = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, fdinfo_buf, sz);
- if (r < 0 || r > sz)
- goto fallback;
- for (i = 0; i < r / (int)PROC_PIDLISTFD_SIZE; i++) {
- if (fdinfo_buf[i].proc_fd >= lowfd)
- close(fdinfo_buf[i].proc_fd);
- }
- free(fdinfo_buf);
- return;
- fallback:
- free(fdinfo_buf);
- closefrom_fallback(lowfd);
- return;
- }
- #elif defined(HAVE_DIRFD) && defined(HAVE_PROC_PID)
- void
- closefrom(int lowfd)
- {
- long fd;
- char fdpath[PATH_MAX], *endp;
- struct dirent *dent;
- DIR *dirp;
- int len;
-
- #ifdef HAVE_CLOSE_RANGE
- if (close_range(lowfd, INT_MAX, 0) == 0)
- return;
- #endif
-
- /* Check for a /proc/$$/fd directory. */
- len = snprintf(fdpath, sizeof(fdpath), "/proc/%ld/fd", (long)getpid());
- if (len > 0 && (size_t)len < sizeof(fdpath) && (dirp = opendir(fdpath))) {
- while ((dent = readdir(dirp)) != NULL) {
- fd = strtol(dent->d_name, &endp, 10);
- if (dent->d_name != endp && *endp == '\0' &&
- fd >= 0 && fd < INT_MAX && fd >= lowfd && fd != dirfd(dirp))
- (void) close((int) fd);
- }
- (void) closedir(dirp);
- return;
- }
- /* /proc/$$/fd strategy failed, fall back to brute force closure */
- closefrom_fallback(lowfd);
- }
- #else
- void
- closefrom(int lowfd)
- {
- closefrom_fallback(lowfd);
- }
- #endif /* !HAVE_FCNTL_CLOSEM */
- #endif /* HAVE_CLOSEFROM */
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