2 * Copyright (c) 2004-2005 Todd C. Miller <Todd.Miller@courtesan.com>
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 #if !defined(HAVE_CLOSEFROM) || defined(BROKEN_CLOSEFROM)
21 #include <sys/types.h>
34 # define NAMLEN(dirent) strlen((dirent)->d_name)
36 # define dirent direct
37 # define NAMLEN(dirent) (dirent)->d_namlen
38 # ifdef HAVE_SYS_NDIR_H
39 # include <sys/ndir.h>
41 # ifdef HAVE_SYS_DIR_H
48 #if defined(HAVE_LIBPROC_H)
57 __unused static const char rcsid[] = "$Sudo: closefrom.c,v 1.11 2006/08/17 15:26:54 millert Exp $";
60 #ifndef HAVE_FCNTL_CLOSEM
62 * Close all file descriptors greater than or equal to lowfd.
65 closefrom_fallback(int lowfd)
70 * Fall back on sysconf() or getdtablesize(). We avoid checking
71 * resource limits since it is possible to open a file descriptor
72 * and then drop the rlimit such that it is below the open fd.
75 maxfd = sysconf(_SC_OPEN_MAX);
77 maxfd = getdtablesize();
78 #endif /* HAVE_SYSCONF */
82 for (fd = lowfd; fd < maxfd; fd++)
83 (void) close((int) fd);
85 #endif /* HAVE_FCNTL_CLOSEM */
87 #ifdef HAVE_FCNTL_CLOSEM
91 (void) fcntl(lowfd, F_CLOSEM, 0);
93 #elif defined(HAVE_LIBPROC_H) && defined(HAVE_PROC_PIDINFO)
99 struct proc_fdinfo *fdinfo_buf = NULL;
101 sz = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, NULL, 0);
103 return; /* no fds, really? */
106 if ((fdinfo_buf = malloc(sz)) == NULL)
108 r = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, fdinfo_buf, sz);
111 for (i = 0; i < r / (int)PROC_PIDLISTFD_SIZE; i++) {
112 if (fdinfo_buf[i].proc_fd >= lowfd)
113 close(fdinfo_buf[i].proc_fd);
119 closefrom_fallback(lowfd);
122 #elif defined(HAVE_DIRFD) && defined(HAVE_PROC_PID)
127 char fdpath[PATH_MAX], *endp;
132 #ifdef HAVE_CLOSE_RANGE
133 if (close_range(lowfd, INT_MAX, 0) == 0)
137 /* Check for a /proc/$$/fd directory. */
138 len = snprintf(fdpath, sizeof(fdpath), "/proc/%ld/fd", (long)getpid());
139 if (len > 0 && (size_t)len < sizeof(fdpath) && (dirp = opendir(fdpath))) {
140 while ((dent = readdir(dirp)) != NULL) {
141 fd = strtol(dent->d_name, &endp, 10);
142 if (dent->d_name != endp && *endp == '\0' &&
143 fd >= 0 && fd < INT_MAX && fd >= lowfd && fd != dirfd(dirp))
144 (void) close((int) fd);
146 (void) closedir(dirp);
149 /* /proc/$$/fd strategy failed, fall back to brute force closure */
150 closefrom_fallback(lowfd);
156 closefrom_fallback(lowfd);
158 #endif /* !HAVE_FCNTL_CLOSEM */
159 #endif /* HAVE_CLOSEFROM */