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xdg-app-helper.c
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/* xdg-app-helper
* Copyright (C) 2014 Alexander Larsson
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "config.h"
#include <assert.h>
#include <arpa/inet.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <linux/loop.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <net/if.h>
#include <netinet/in.h>
#include <sched.h>
#include <signal.h>
#include <poll.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/eventfd.h>
#include <sys/signalfd.h>
#include <sys/capability.h>
#include <sys/prctl.h>
#include <unistd.h>
#if 0
#define __debug__(x) printf x
#else
#define __debug__(x)
#endif
#define N_ELEMENTS(arr) (sizeof (arr) / sizeof ((arr)[0]))
#define TRUE 1
#define FALSE 0
typedef int bool;
#define READ_END 0
#define WRITE_END 1
static void
die_with_error (const char *format, ...)
{
va_list args;
int errsv;
errsv = errno;
va_start (args, format);
vfprintf (stderr, format, args);
va_end (args);
fprintf (stderr, ": %s\n", strerror (errsv));
exit (1);
}
static void
die (const char *format, ...)
{
va_list args;
va_start (args, format);
vfprintf (stderr, format, args);
va_end (args);
fprintf (stderr, "\n");
exit (1);
}
static void *
xmalloc (size_t size)
{
void *res = malloc (size);
if (res == NULL)
die ("oom");
return res;
}
static void *
xrealloc (void *ptr, size_t size)
{
void *res = realloc (ptr, size);
if (size != 0 && res == NULL)
die ("oom");
return res;
}
static char *
xstrdup (const char *str)
{
char *res;
assert (str != NULL);
res = strdup (str);
if (res == NULL)
die ("oom");
return res;
}
static void
xsetenv (const char *name, const char *value, int overwrite)
{
if (setenv (name, value, overwrite))
die ("setenv failed");
}
static void
xunsetenv (const char *name)
{
if (unsetenv(name))
die ("unsetenv failed");
}
char *
strconcat (const char *s1,
const char *s2)
{
size_t len = 0;
char *res;
if (s1)
len += strlen (s1);
if (s2)
len += strlen (s2);
res = xmalloc (len + 1);
*res = 0;
if (s1)
strcat (res, s1);
if (s2)
strcat (res, s2);
return res;
}
char *
strconcat3 (const char *s1,
const char *s2,
const char *s3)
{
size_t len = 0;
char *res;
if (s1)
len += strlen (s1);
if (s2)
len += strlen (s2);
if (s3)
len += strlen (s3);
res = xmalloc (len + 1);
*res = 0;
if (s1)
strcat (res, s1);
if (s2)
strcat (res, s2);
if (s3)
strcat (res, s3);
return res;
}
char *
strconcat_len (const char *s1,
const char *s2,
size_t s2_len)
{
size_t len = 0;
char *res;
if (s1)
len += strlen (s1);
if (s2)
len += s2_len;
res = xmalloc (len + 1);
*res = 0;
if (s1)
strcat (res, s1);
if (s2)
strncat (res, s2, s2_len);
return res;
}
char*
strdup_printf (const char *format,
...)
{
char *buffer = NULL;
va_list args;
va_start (args, format);
vasprintf (&buffer, format, args);
va_end (args);
if (buffer == NULL)
die ("oom");
return buffer;
}
#ifndef HAVE_FDWALK
static int
fdwalk (int (*cb)(void *data, int fd), void *data)
{
int open_max;
int fd;
int res = 0;
DIR *d;
if ((d = opendir ("/proc/self/fd")))
{
struct dirent *de;
while ((de = readdir (d)))
{
long l;
char *e = NULL;
if (de->d_name[0] == '.')
continue;
errno = 0;
l = strtol (de->d_name, &e, 10);
if (errno != 0 || !e || *e)
continue;
fd = (int) l;
if ((long) fd != l)
continue;
if (fd == dirfd (d))
continue;
if ((res = cb (data, fd)) != 0)
break;
}
closedir (d);
return res;
}
open_max = sysconf (_SC_OPEN_MAX);
for (fd = 0; fd < open_max; fd++)
if ((res = cb (data, fd)) != 0)
break;
return res;
}
#endif
static inline int raw_clone(unsigned long flags, void *child_stack) {
#if defined(__s390__) || defined(__CRIS__)
/* On s390 and cris the order of the first and second arguments
* of the raw clone() system call is reversed. */
return (int) syscall(__NR_clone, child_stack, flags);
#else
return (int) syscall(__NR_clone, flags, child_stack);
#endif
}
void
usage (char **argv)
{
fprintf (stderr, "usage: %s [OPTIONS...] RUNTIMEPATH COMMAND [ARGS...]\n\n", argv[0]);
fprintf (stderr,
" -a Specify path for application (mounted at /app)\n"
" -b DEST[=SOURCE] Bind extra source path readonly into DEST\n"
" -B DEST[=SOURCE] Bind extra source path into DEST\n"
" -M DEST[=SOURCE] Bind extra source path into DEST and remove original\n"
" -d SOCKETPATH Use SOCKETPATH as dbus session bus\n"
" -D SOCKETPATH Use SOCKETPATH as dbus system bus\n"
" -e Make /app/exports writable\n"
" -E Make /etc a pure symlink to /usr/etc\n"
" -f Mount the host filesystems\n"
" -g Allow use of direct rendering graphics\n"
" -F Mount the host filesystems read-only\n"
" -H Mount the users home directory (implied by -f)\n"
" -i Share IPC namespace with session\n"
" -I APPID Set app id (used to find app data)\n"
" -l Lock .ref files in all mounts\n"
" -m PATH Set path to xdg-app-session-helper output\n"
" -n Share network namespace with session\n"
" -p SOCKETPATH Use SOCKETPATH as pulseaudio connection\n"
" -s Share Shm namespace with session\n"
" -v PATH Mount PATH as /var\n"
" -w Make /app writable\n"
" -W Make /usr writable\n"
" -x SOCKETPATH Use SOCKETPATH as X display\n"
" -y SOCKETPATH Use SOCKETPATH as Wayland display\n"
);
exit (1);
}
static int
pivot_root (const char * new_root, const char * put_old)
{
#ifdef __NR_pivot_root
return syscall(__NR_pivot_root, new_root, put_old);
#else
errno = ENOSYS;
return -1;
#endif
}
typedef enum {
FILE_TYPE_REGULAR,
FILE_TYPE_DIR,
FILE_TYPE_SYMLINK,
FILE_TYPE_SYSTEM_SYMLINK,
FILE_TYPE_BIND,
FILE_TYPE_BIND_RO,
FILE_TYPE_MOUNT,
FILE_TYPE_REMOUNT,
FILE_TYPE_DEVICE,
FILE_TYPE_SHM,
} file_type_t;
typedef enum {
FILE_FLAGS_NONE = 0,
FILE_FLAGS_NON_FATAL = 1 << 0,
FILE_FLAGS_IF_LAST_FAILED = 1 << 1,
FILE_FLAGS_DEVICES = 1 << 2,
} file_flags_t;
typedef struct {
file_type_t type;
const char *name;
mode_t mode;
const char *data;
file_flags_t flags;
int *option;
} create_table_t;
typedef struct {
const char *what;
const char *where;
const char *type;
const char *options;
unsigned long flags;
} mount_table_t;
int
ascii_isdigit (char c)
{
return c >= '0' && c <= '9';
}
static bool create_etc_symlink = FALSE;
static bool create_etc_dir = TRUE;
static bool create_monitor_links = FALSE;
static bool bind_resolv_conf = FALSE;
static bool allow_dri = FALSE;
static const create_table_t create[] = {
{ FILE_TYPE_DIR, ".oldroot", 0755 },
{ FILE_TYPE_DIR, "usr", 0755 },
{ FILE_TYPE_DIR, "tmp", 01777 },
{ FILE_TYPE_DIR, "app", 0755},
{ FILE_TYPE_DIR, "run", 0755},
{ FILE_TYPE_DIR, "run/host", 0755},
{ FILE_TYPE_DIR, "run/dbus", 0755},
{ FILE_TYPE_DIR, "run/media", 0755},
{ FILE_TYPE_DIR, "run/user", 0755},
{ FILE_TYPE_DIR, "run/user/%1$d", 0700, NULL},
{ FILE_TYPE_DIR, "run/user/%1$d/pulse", 0700, NULL},
{ FILE_TYPE_DIR, "run/user/%1$d/dconf", 0700, NULL},
{ FILE_TYPE_DIR, "run/user/%1$d/xdg-app-monitor", 0700, NULL},
{ FILE_TYPE_REGULAR, "run/user/%1$d/pulse/native", 0700, NULL},
{ FILE_TYPE_DIR, "var", 0755},
{ FILE_TYPE_SYMLINK, "var/tmp", 0755, "/tmp"},
{ FILE_TYPE_SYMLINK, "var/run", 0755, "/run"},
{ FILE_TYPE_SYSTEM_SYMLINK, "lib32", 0755, "usr/lib32"},
{ FILE_TYPE_SYSTEM_SYMLINK, "lib64", 0755, "usr/lib64"},
{ FILE_TYPE_SYSTEM_SYMLINK, "lib", 0755, "usr/lib"},
{ FILE_TYPE_SYSTEM_SYMLINK, "bin", 0755, "usr/bin" },
{ FILE_TYPE_SYSTEM_SYMLINK, "sbin", 0755, "usr/sbin"},
{ FILE_TYPE_SYMLINK, "etc", 0755, "usr/etc", 0, &create_etc_symlink},
{ FILE_TYPE_DIR, "etc", 0755, NULL, 0, &create_etc_dir},
{ FILE_TYPE_REGULAR, "etc/passwd", 0755, NULL, 0, &create_etc_dir},
{ FILE_TYPE_REGULAR, "etc/group", 0755, NULL, 0, &create_etc_dir},
{ FILE_TYPE_REGULAR, "etc/resolv.conf", 0755, NULL, 0, &bind_resolv_conf},
{ FILE_TYPE_SYMLINK, "etc/resolv.conf", 0755, "/run/user/%1$d/xdg-app-monitor/resolv.conf", 0, &create_monitor_links},
{ FILE_TYPE_REGULAR, "etc/machine-id", 0755, NULL, 0, &create_etc_dir},
{ FILE_TYPE_DIR, "tmp/.X11-unix", 0755 },
{ FILE_TYPE_REGULAR, "tmp/.X11-unix/X99", 0755 },
{ FILE_TYPE_DIR, "proc", 0755},
{ FILE_TYPE_MOUNT, "proc"},
{ FILE_TYPE_BIND_RO, "proc/sys", 0755, "proc/sys"},
{ FILE_TYPE_BIND_RO, "proc/sysrq-trigger", 0755, "proc/sysrq-trigger"},
{ FILE_TYPE_BIND_RO, "proc/irq", 0755, "proc/irq"},
{ FILE_TYPE_BIND_RO, "proc/bus", 0755, "proc/bus"},
{ FILE_TYPE_DIR, "sys", 0755},
{ FILE_TYPE_DIR, "sys/block", 0755},
{ FILE_TYPE_BIND_RO, "sys/block", 0755, "/sys/block"},
{ FILE_TYPE_DIR, "sys/bus", 0755},
{ FILE_TYPE_BIND_RO, "sys/bus", 0755, "/sys/bus"},
{ FILE_TYPE_DIR, "sys/class", 0755},
{ FILE_TYPE_BIND_RO, "sys/class", 0755, "/sys/class"},
{ FILE_TYPE_DIR, "sys/dev", 0755},
{ FILE_TYPE_BIND_RO, "sys/dev", 0755, "/sys/dev"},
{ FILE_TYPE_DIR, "sys/devices", 0755},
{ FILE_TYPE_BIND_RO, "sys/devices", 0755, "/sys/devices"},
{ FILE_TYPE_DIR, "dev", 0755},
{ FILE_TYPE_MOUNT, "dev"},
{ FILE_TYPE_DIR, "dev/pts", 0755},
{ FILE_TYPE_MOUNT, "dev/pts"},
{ FILE_TYPE_DIR, "dev/shm", 0755},
{ FILE_TYPE_SHM, "dev/shm"},
{ FILE_TYPE_DEVICE, "dev/null", 0666},
{ FILE_TYPE_DEVICE, "dev/zero", 0666},
{ FILE_TYPE_DEVICE, "dev/full", 0666},
{ FILE_TYPE_DEVICE, "dev/random", 0666},
{ FILE_TYPE_DEVICE, "dev/urandom", 0666},
{ FILE_TYPE_DEVICE, "dev/tty", 0666},
{ FILE_TYPE_DIR, "dev/dri", 0755},
{ FILE_TYPE_BIND_RO, "dev/dri", 0755, "/dev/dri", FILE_FLAGS_NON_FATAL|FILE_FLAGS_DEVICES, &allow_dri},
{ FILE_TYPE_REMOUNT, "dev", MS_RDONLY|MS_NOSUID|MS_NOEXEC},
};
/* warning: Don't create any actual files here, as we could potentially
write over bind mounts to the system */
static const create_table_t create_post[] = {
{ FILE_TYPE_BIND_RO, "etc/passwd", 0444, "/etc/passwd", 0},
{ FILE_TYPE_BIND_RO, "etc/group", 0444, "/etc/group", 0},
{ FILE_TYPE_BIND_RO, "etc/machine-id", 0444, "/etc/machine-id", FILE_FLAGS_NON_FATAL},
{ FILE_TYPE_BIND_RO, "etc/machine-id", 0444, "/var/lib/dbus/machine-id", FILE_FLAGS_NON_FATAL | FILE_FLAGS_IF_LAST_FAILED},
{ FILE_TYPE_BIND_RO, "etc/resolv.conf", 0444, "/etc/resolv.conf", 0, &bind_resolv_conf},
};
static const mount_table_t mount_table[] = {
{ "proc", "proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV },
{ "tmpfs", "dev", "tmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME },
{ "devpts", "dev/pts", "devpts","newinstance,ptmxmode=0666,mode=620,gid=5", MS_NOSUID|MS_NOEXEC },
{ "tmpfs", "dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME },
};
const char *dont_mount_in_root[] = {
".", "..", "lib", "lib32", "lib64", "bin", "sbin", "usr", "boot", "root",
"tmp", "etc", "app", "run", "proc", "sys", "dev", "var"
};
typedef enum {
BIND_READONLY = (1<<0),
BIND_PRIVATE = (1<<1),
BIND_DEVICES = (1<<2),
BIND_RECURSIVE = (1<<3),
} bind_option_t;
typedef struct {
char *src;
char *dest;
bool readonly;
bool move;
} ExtraFile;
ExtraFile *extra_files = NULL;
int n_extra_files = 0;
static void
add_extra_file (char *src, char *dest, bool readonly, bool move)
{
int i = n_extra_files;
n_extra_files++;
extra_files = xrealloc (extra_files, n_extra_files * sizeof (ExtraFile));
extra_files[i].src = src;
extra_files[i].dest = dest;
extra_files[i].readonly = readonly;
extra_files[i].move = move;
}
static int n_lock_dirs = 0;
static const char **lock_dirs = NULL;
static void
lock_dir (const char *dir)
{
char *file = strconcat3 ("/", dir, "/.ref");
struct flock lock = {0};
int fd;
fd = open (file, O_RDONLY | O_CLOEXEC);
free (file);
if (fd != -1)
{
lock.l_type = F_RDLCK;
lock.l_whence = SEEK_SET;
lock.l_start = 0;
lock.l_len = 0;
if (fcntl(fd, F_SETLK, &lock) < 0)
{
printf ("lock failed\n");
close (fd);
}
}
}
static void
add_lock_dir (const char *dir)
{
int i = n_lock_dirs;
n_lock_dirs++;
lock_dirs = xrealloc (lock_dirs, n_lock_dirs * sizeof (char *));
lock_dirs[i] = dir;
}
/* We need to lock the dirs in pid1 because otherwise the
locks are not held by the right process and will not live
for the full duration of the sandbox. */
static void
lock_all_dirs (void)
{
int i;
for (i = 0; i < n_lock_dirs; i++)
lock_dir (lock_dirs[i]);
}
static char *
load_file (const char *path)
{
int fd;
char *data;
ssize_t data_read;
ssize_t data_len;
ssize_t res;
fd = open (path, O_CLOEXEC | O_RDONLY);
if (fd == -1)
return NULL;
data_read = 0;
data_len = 4080;
data = xmalloc (data_len);
do
{
if (data_len >= data_read + 1)
{
data_len *= 2;
data = xrealloc (data, data_len);
}
do
res = read (fd, data + data_read, data_len - data_read - 1);
while (res < 0 && errno == EINTR);
if (res < 0)
{
int errsv = errno;
free (data);
errno = errsv;
return NULL;
}
data_read += res;
}
while (res > 0);
data[data_read] = 0;
close (fd);
return data;
}
static char *
skip_line (char *line)
{
while (*line != 0 && *line != '\n')
line++;
if (*line == '\n')
line++;
return line;
}
static char *
skip_token (char *line, bool eat_whitespace)
{
while (*line != ' ' && *line != '\n')
line++;
if (eat_whitespace && *line == ' ')
line++;
return line;
}
static bool
str_has_prefix (const char *str,
const char *prefix)
{
return strncmp (str, prefix, strlen (prefix)) == 0;
}
char **
get_submounts (const char *parent_mount)
{
char *mountpoint, *mountpoint_end;
char **submounts;
int i, n_submounts, submounts_size;
char *mountinfo;
char *line;
mountinfo = load_file ("/proc/self/mountinfo");
if (mountinfo == NULL)
return NULL;
submounts_size = 8;
n_submounts = 0;
submounts = xmalloc (sizeof (char *) * submounts_size);
line = mountinfo;
while (*line != 0)
{
for (i = 0; i < 4; i++)
line = skip_token (line, TRUE);
mountpoint = line;
line = skip_token (line, FALSE);
mountpoint_end = line;
line = skip_line (line);
*mountpoint_end = 0;
if (*mountpoint == '/' &&
str_has_prefix (mountpoint + 1, parent_mount) &&
*(mountpoint + 1 + strlen (parent_mount)) == '/')
{
if (n_submounts + 1 >= submounts_size)
{
submounts_size *= 2;
submounts = xrealloc (submounts, sizeof (char *) * submounts_size);
}
submounts[n_submounts++] = xstrdup (mountpoint + 1);
}
}
submounts[n_submounts] = NULL;
free (mountinfo);
return submounts;
}
static int
bind_mount (const char *src, const char *dest, bind_option_t options)
{
bool readonly = (options & BIND_READONLY) != 0;
bool private = (options & BIND_PRIVATE) != 0;
bool devices = (options & BIND_DEVICES) != 0;
bool recursive = (options & BIND_RECURSIVE) != 0;
char **submounts;
int i;
if (mount (src, dest, NULL, MS_MGC_VAL|MS_BIND|(recursive?MS_REC:0), NULL) != 0)
return 1;
if (private)
{
if (mount ("none", dest,
NULL, MS_REC|MS_PRIVATE, NULL) != 0)
return 2;
}
if (mount ("none", dest,
NULL, MS_MGC_VAL|MS_BIND|MS_REMOUNT|(devices?0:MS_NODEV)|MS_NOSUID|(readonly?MS_RDONLY:0), NULL) != 0)
return 3;
/* We need to work around the fact that a bind mount does not apply the flags, so we need to manually
* apply the flags to all submounts in the recursive case.
* Note: This does not apply the flags to mounts which are later propagated into this namespace.
*/
if (recursive)
{
submounts = get_submounts (dest);
if (submounts == NULL)
return 4;
for (i = 0; submounts[i] != NULL; i++)
{
if (mount ("none", submounts[i],
NULL, MS_MGC_VAL|MS_BIND|MS_REMOUNT|(devices?0:MS_NODEV)|MS_NOSUID|(readonly?MS_RDONLY:0), NULL) != 0)
return 5;
free (submounts[i]);
}
free (submounts);
}
return 0;
}
static bool
stat_is_dir (const char *pathname)
{
struct stat buf;
if (stat (pathname, &buf) != 0)
return FALSE;
return S_ISDIR (buf.st_mode);
}
static int
mkdir_with_parents (const char *pathname,
int mode,
bool create_last)
{
char *fn, *p;
struct stat buf;
if (pathname == NULL || *pathname == '\0')
{
errno = EINVAL;
return 1;
}
fn = xstrdup (pathname);
p = fn;
while (*p == '/')
p++;
do
{
while (*p && *p != '/')
p++;
if (!*p)
p = NULL;
else
*p = '\0';
if (!create_last && p == NULL)
break;
if (stat (fn, &buf) != 0)
{
if (mkdir (fn, mode) == -1 && errno != EEXIST)
{
int errsave = errno;
free (fn);
errno = errsave;
return -1;
}
}
else if (!S_ISDIR (buf.st_mode))
{
free (fn);
errno = ENOTDIR;
return -1;
}
if (p)
{
*p++ = '/';
while (*p && *p == '/')
p++;
}
}
while (p);
free (fn);
return 0;
}
static bool
write_to_file (int fd, const char *content, ssize_t len)
{
ssize_t res;
while (len > 0)
{
res = write (fd, content, len);
if (res < 0 && errno == EINTR)
continue;
if (res <= 0)
return FALSE;
len -= res;
content += res;
}
return TRUE;
}
#define BUFSIZE 8192
static bool
copy_file_data (int sfd,
int dfd)
{
char buffer[BUFSIZE];
ssize_t bytes_read;
while (TRUE)
{
bytes_read = read (sfd, buffer, BUFSIZE);
if (bytes_read == -1)
{
if (errno == EINTR)
continue;
return FALSE;;
}
if (bytes_read == 0)
break;
if (!write_to_file (dfd, buffer, bytes_read))
return FALSE;
}
return TRUE;
}
static bool
copy_file (const char *src_path, const char *dst_path, mode_t mode)
{
int sfd, dfd;
bool res;
int errsv;
sfd = open (src_path, O_CLOEXEC | O_RDONLY);
if (sfd == -1)
return FALSE;
dfd = creat (dst_path, mode);
if (dfd == -1)
{
close (sfd);
return FALSE;
}
res = copy_file_data (sfd, dfd);
errsv = errno;
close (sfd);
close (dfd);
errno = errsv;
return res;
}
static bool
create_file (const char *path, mode_t mode, const char *content)
{
int fd;
int res;
int errsv;
fd = creat (path, mode);
if (fd == -1)
return FALSE;
res = TRUE;
if (content)
res = write_to_file (fd, content, strlen (content));
errsv = errno;
close (fd);
errno = errsv;
return res;
}
static void
create_files (const create_table_t *create, int n_create, int ignore_shm, const char *usr_path)
{
bool last_failed = FALSE;
int i;
int system_mode = FALSE;
if (strcmp (usr_path, "/usr") == 0)
system_mode = TRUE;
for (i = 0; i < n_create; i++)
{
char *name;
char *data = NULL;
mode_t mode = create[i].mode;
file_flags_t flags = create[i].flags;
int *option = create[i].option;
char *in_root;
int k;
bool found;
int res;
if ((flags & FILE_FLAGS_IF_LAST_FAILED) &&
!last_failed)
continue;
if (option && !*option)
continue;
name = strdup_printf (create[i].name, getuid());
if (create[i].data)
data = strdup_printf (create[i].data, getuid());
last_failed = FALSE;
switch (create[i].type)
{
case FILE_TYPE_DIR:
if (mkdir (name, mode) != 0)
die_with_error ("creating dir %s", name);
break;
case FILE_TYPE_REGULAR:
if (!create_file (name, mode, NULL))
die_with_error ("creating file %s", name);
break;
case FILE_TYPE_SYSTEM_SYMLINK:
if (system_mode)
{
struct stat buf;
in_root = strconcat ("/", name);
if (stat (in_root, &buf) == 0)
{
if (mkdir (name, mode) != 0)
die_with_error ("creating dir %s", name);
if (bind_mount (in_root, name, BIND_PRIVATE | BIND_READONLY))
die_with_error ("mount %s", name);
}
free (in_root);
break;
}
/* Only create symlink if target exists */
if (data != NULL && str_has_prefix (data, "usr/"))
{
struct stat buf;
char *in_usr = strconcat3 (usr_path, "/", data + strlen("usr/"));
int res;
res = lstat (in_usr, &buf);
free (in_usr);
if (res != 0)
data = NULL;
}
else
data = NULL;
if (data == NULL)
break;
/* else Fall through */
case FILE_TYPE_SYMLINK:
if (symlink (data, name) != 0)
die_with_error ("creating symlink %s", name);
break;
case FILE_TYPE_BIND:
case FILE_TYPE_BIND_RO:
if ((res = bind_mount (data, name,
0 |
((create[i].type == FILE_TYPE_BIND_RO) ? BIND_READONLY : 0) |
((flags & FILE_FLAGS_DEVICES) ? BIND_DEVICES : 0))))