156 lines
3.8 KiB
C
156 lines
3.8 KiB
C
/*
|
|
* 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"
|
|
|
|
#ifndef HAVE_CLOSEFROM
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/param.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>
|
|
#include <unistd.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;
|
|
|
|
/* 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 */
|