You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

292 lines
6.7 KiB

/*
* plausible.c --- Figure out if a pathname is ext* or something else.
*
* Copyright 2014, Oracle, Inc.
*
* Some parts are:
* Copyright 1995, 1996, 1997, 1998, 1999, 2000 by Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %End-Header%
*/
#ifndef _LARGEFILE_SOURCE
#define _LARGEFILE_SOURCE
#endif
#ifndef _LARGEFILE64_SOURCE
#define _LARGEFILE64_SOURCE
#endif
#include "config.h"
#include <fcntl.h>
#include <time.h>
#include <sys/types.h>
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_MAGIC_H
#include <magic.h>
#endif
#include "plausible.h"
#include "ext2fs/ext2fs.h"
#include "nls-enable.h"
#include "blkid/blkid.h"
#ifdef HAVE_MAGIC_H
static magic_t (*dl_magic_open)(int);
static const char *(*dl_magic_file)(magic_t, const char *);
static int (*dl_magic_load)(magic_t, const char *);
static void (*dl_magic_close)(magic_t);
/*
* NO_CHECK functionality was only added in file 4.20.
* Older systems like RHEL 5.x still have file 4.17
*/
#ifndef MAGIC_NO_CHECK_COMPRESS
#define MAGIC_NO_CHECK_COMPRESS 0x0001000
#endif
#ifndef MAGIC_NO_CHECK_ELF
#define MAGIC_NO_CHECK_ELF 0x0010000
#endif
#ifdef HAVE_DLOPEN
#include <dlfcn.h>
static void *magic_handle;
static int magic_library_available(void)
{
if (!magic_handle) {
magic_handle = dlopen("libmagic.so.1", RTLD_NOW);
if (!magic_handle)
return 0;
dl_magic_open = (magic_t (*)(int))
dlsym(magic_handle, "magic_open");
dl_magic_file = (const char *(*)(magic_t, const char *))
dlsym(magic_handle, "magic_file");
dl_magic_load = (int (*)(magic_t, const char *))
dlsym(magic_handle, "magic_load");
dl_magic_close = (void (*)(magic_t))
dlsym(magic_handle, "magic_close");
}
if (!dl_magic_open || !dl_magic_file ||
!dl_magic_load || !dl_magic_close)
return 0;
return 1;
}
#else
static int magic_library_available(void)
{
dl_magic_open = magic_open;
dl_magic_file = magic_file;
dl_magic_load = magic_load;
dl_magic_close = magic_close;
return 1;
}
#endif
#endif
static void print_ext2_info(const char *device)
{
struct ext2_super_block *sb;
ext2_filsys fs;
errcode_t retval;
time_t tm;
char buf[80];
retval = ext2fs_open2(device, 0, EXT2_FLAG_64BITS, 0, 0,
unix_io_manager, &fs);
if (retval)
return;
sb = fs->super;
if (sb->s_mtime) {
tm = sb->s_mtime;
if (sb->s_last_mounted[0]) {
memset(buf, 0, sizeof(buf));
strncpy(buf, sb->s_last_mounted,
sizeof(sb->s_last_mounted));
printf(_("\tlast mounted on %s on %s"), buf,
ctime(&tm));
} else
printf(_("\tlast mounted on %s"), ctime(&tm));
} else if (sb->s_mkfs_time) {
tm = sb->s_mkfs_time;
printf(_("\tcreated on %s"), ctime(&tm));
} else if (sb->s_wtime) {
tm = sb->s_wtime;
printf(_("\tlast modified on %s"), ctime(&tm));
}
ext2fs_close_free(&fs);
}
/*
* return 1 if there is no partition table, 0 if a partition table is
* detected, and -1 on an error.
*/
#ifdef HAVE_BLKID_PROBE_ENABLE_PARTITIONS
static int check_partition_table(const char *device)
{
blkid_probe pr;
const char *value;
int ret;
pr = blkid_new_probe_from_filename(device);
if (!pr)
return -1;
ret = blkid_probe_enable_partitions(pr, 1);
if (ret < 0)
goto errout;
ret = blkid_probe_enable_superblocks(pr, 0);
if (ret < 0)
goto errout;
ret = blkid_do_fullprobe(pr);
if (ret < 0)
goto errout;
ret = blkid_probe_lookup_value(pr, "PTTYPE", &value, NULL);
if (ret == 0)
fprintf(stderr, _("Found a %s partition table in %s\n"),
value, device);
else
ret = 1;
errout:
blkid_free_probe(pr);
return ret;
}
#else
static int check_partition_table(const char *device EXT2FS_ATTR((unused)))
{
return -1;
}
#endif
/*
* return 1 if the device looks plausible, creating the file if necessary
*/
int check_plausibility(const char *device, int flags, int *ret_is_dev)
{
int fd, ret, is_dev = 0;
ext2fs_struct_stat s;
int fl = O_RDONLY;
blkid_cache cache = NULL;
char *fs_type = NULL;
char *fs_label = NULL;
fd = ext2fs_open_file(device, fl, 0666);
if ((fd < 0) && (errno == ENOENT) && (flags & NO_SIZE)) {
fprintf(stderr, _("The file %s does not exist and no "
"size was specified.\n"), device);
exit(1);
}
if ((fd < 0) && (errno == ENOENT) && (flags & CREATE_FILE)) {
fl |= O_CREAT;
fd = ext2fs_open_file(device, fl, 0666);
if (fd >= 0 && (flags & VERBOSE_CREATE))
printf(_("Creating regular file %s\n"), device);
}
if (fd < 0) {
fprintf(stderr, _("Could not open %s: %s\n"),
device, error_message(errno));
if (errno == ENOENT)
fputs(_("\nThe device apparently does not exist; "
"did you specify it correctly?\n"), stderr);
exit(1);
}
if (ext2fs_fstat(fd, &s) < 0) {
perror("stat");
exit(1);
}
close(fd);
if (S_ISBLK(s.st_mode))
is_dev = 1;
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
/* On FreeBSD, all disk devices are character specials */
if (S_ISCHR(s.st_mode))
is_dev = 1;
#endif
if (ret_is_dev)
*ret_is_dev = is_dev;
if ((flags & CHECK_BLOCK_DEV) && !is_dev) {
printf(_("%s is not a block special device.\n"), device);
return 0;
}
/*
* Note: we use the older-style blkid API's here because we
* want as much functionality to be available when using the
* internal blkid library, when e2fsprogs is compiled for
* non-Linux systems that will probably not have the libraries
* from util-linux available. We only use the newer
* blkid-probe interfaces to access functionality not
* available in the original blkid library.
*/
if ((flags & CHECK_FS_EXIST) && blkid_get_cache(&cache, NULL) >= 0) {
fs_type = blkid_get_tag_value(cache, "TYPE", device);
if (fs_type)
fs_label = blkid_get_tag_value(cache, "LABEL", device);
blkid_put_cache(cache);
}
if (fs_type) {
if (fs_label)
printf(_("%s contains a %s file system labelled '%s'\n"),
device, fs_type, fs_label);
else
printf(_("%s contains a %s file system\n"), device,
fs_type);
if (strncmp(fs_type, "ext", 3) == 0)
print_ext2_info(device);
free(fs_type);
free(fs_label);
return 0;
}
#ifdef HAVE_MAGIC_H
if ((flags & CHECK_FS_EXIST) &&
!getenv("E2FSPROGS_LIBMAGIC_SUPPRESS") &&
magic_library_available()) {
const char *msg;
magic_t mag;
int has_magic = 0;
mag = dl_magic_open(MAGIC_RAW | MAGIC_SYMLINK | MAGIC_DEVICES |
MAGIC_ERROR | MAGIC_NO_CHECK_ELF |
MAGIC_NO_CHECK_COMPRESS);
dl_magic_load(mag, NULL);
msg = dl_magic_file(mag, device);
if (msg && strcmp(msg, "data") && strcmp(msg, "empty")) {
printf(_("%s contains `%s' data\n"), device, msg);
has_magic = 1;
}
dl_magic_close(mag);
return !has_magic;
}
#endif
ret = check_partition_table(device);
if (ret >= 0)
return ret;
return 1;
}