ext2文件系统中inode属性修改

csdn · 发表于 2015-1-21 15:20:24

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <time.h>
#include <getopt.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <ext2fs/ext2fs.h>
/*
* Flags used by the common argument processing functions
*/
#define CHECK_FS_RW 0x0001
#define CHECK_FS_BITMAPS 0x0002
#define CHECK_FS_NOTOPEN 0x0004
#ifdef DLL_EXPORT
#define DLLEXPORT __declspec(dllexport)
#else
#define DLLEXPORT
#endif
ext2_filsys current_fs = NULL;
ext2_ino_t root, cwd;
DLLEXPORT
int open_filesystem(char *device, int open_flags, blk_t superblock,
blk_t blocksize, int catastrophic)
{
int retval;
if (superblock != 0 && blocksize == 0) {
com_err(device, 0, "if you specify the superblock, you must also specify the block size");
current_fs = NULL;
return;
}
if (catastrophic && (open_flags & EXT2_FLAG_RW)) {
com_err(device, 0,
"opening read-only because of catastrophic mode");
open_flags &= ~EXT2_FLAG_RW;
}
retval = ext2fs_open(device, open_flags, superblock, blocksize,
nt_io_manager(), ¤t_fs);
if (retval) {
com_err(device, retval, "while opening filesystem");
current_fs = NULL;
return;
}
if (catastrophic)
com_err(device, 0, "catastrophic mode - not reading inode or group bitmaps");
else {
retval = ext2fs_read_inode_bitmap(current_fs);
if (retval) {
com_err(device, retval, "while reading inode bitmap");
goto errout;
}
retval = ext2fs_read_block_bitmap(current_fs);
if (retval) {
com_err(device, retval, "while reading block bitmap");
goto errout;
}
}
root = cwd = EXT2_ROOT_INO;
return 0;
errout:
retval = ext2fs_close(current_fs);
if (retval)
com_err(device, retval, "while trying to close filesystem");
current_fs = NULL;
return -1;
}
DLLEXPORT
void close_filesystem(void)
{
int retval;
if (current_fs->flags & EXT2_FLAG_IB_DIRTY) {
retval = ext2fs_write_inode_bitmap(current_fs);
if (retval)
com_err("ext2fs_write_inode_bitmap", retval, "");
}
if (current_fs->flags & EXT2_FLAG_BB_DIRTY) {
retval = ext2fs_write_block_bitmap(current_fs);
if (retval)
com_err("ext2fs_write_block_bitmap", retval, "");
}
retval = ext2fs_close(current_fs);
if (retval)
com_err("ext2fs_close", retval, "");
current_fs = NULL;
return;
}
/*
* This routine is used whenever a command needs to turn a string into
* an inode.
*/
ext2_ino_t string_to_inode(char *str)
{
ext2_ino_t ino;
int len = strlen(str);
char *end;
int retval;
/*
* If the string is of the form <ino>, then treat it as an
* inode number.
*/
if ((len > 2) && (str[0] == '<') && (str[len-1] == '>')) {
ino = strtoul(str+1, &end, 0);
if (*end=='>')
return ino;
}
retval = ext2fs_namei(current_fs, root, cwd, str, &ino);
if (retval) {
com_err(str, retval, "");
return 0;
}
return ino;
}
/*
* This routine returns 1 if the filesystem is not open, and prints an
* error message to that effect.
*/
int check_fs_open(char *name)
{
if (!current_fs) {
com_err(name, 0, "Filesystem not open");
return 1;
}
return 0;
}
/*
* This routine returns 1 if a filesystem is open, and prints an
* error message to that effect.
*/
int check_fs_not_open(char *name)
{
if (current_fs) {
com_err(name, 0,
"Filesystem %s is still open. Close it first.\n",
current_fs->device_name);
return 1;
}
return 0;
}
/*
* This routine returns 1 if a filesystem is not opened read/write,
* and prints an error message to that effect.
*/
int check_fs_read_write(char *name)
{
if (!(current_fs->flags & EXT2_FLAG_RW)) {
com_err(name, 0, "Filesystem opened read/only");
return 1;
}
return 0;
}
/*
* This routine returns 1 if a filesystem is doesn't have its inode
* and block bitmaps loaded, and prints an error message to that
* effect.
*/
int check_fs_bitmaps(char *name)
{
if (!current_fs->block_map || !current_fs->inode_map) {
com_err(name, 0, "Filesystem bitmaps not loaded");
return 1;
}
return 0;
}
/*
* This function takes a __u32 time value and converts it to a string,
* using ctime
*/
char *time_to_string(__u32 cl)
{
time_t t = (time_t) cl;
return ctime(&t);
}
int debugfs_read_inode(ext2_ino_t ino, struct ext2_inode * inode,
const char *cmd)
{
int retval;
retval = ext2fs_read_inode(current_fs, ino, inode);
if (retval) {
com_err(cmd, retval, "while reading inode %u", ino);
return 1;
}
return 0;
}
int debugfs_write_inode(ext2_ino_t ino, struct ext2_inode * inode,
const char *cmd)
{
int retval;
retval = ext2fs_write_inode(current_fs, ino, inode);
if (retval) {
com_err(cmd, retval, "while writing inode %u", ino);
return 1;
}
return 0;
}
/*
* This is a common helper function used by the command processing
* routines
*/
int common_args_process(int argc, char *argv[], int min_argc, int max_argc,
const char *cmd, const char *usage, int flags)
{
if (argc < min_argc || argc > max_argc) {
com_err(argv[0], 0, "Usage: %s %s", cmd, usage);
return 1;
}
if (flags & CHECK_FS_NOTOPEN) {
if (check_fs_not_open(argv[0]))
return 1;
} else {
if (check_fs_open(argv[0]))
return 1;
}
if ((flags & CHECK_FS_RW) && check_fs_read_write(argv[0]))
return 1;
if ((flags & CHECK_FS_BITMAPS) && check_fs_bitmaps(argv[0]))
return 1;
return 0;
}
/*
* This is a helper function used by do_stat, do_freei, do_seti, and
* do_testi, etc. Basically, any command which takes a single
* argument which is a file/inode number specifier.
*/
int common_inode_args_process(int argc, char *argv[],
ext2_ino_t *inode, int flags)
{
if (common_args_process(argc, argv, 2, 2, argv[0], "<file>", flags))
return 1;
*inode = string_to_inode(argv[1]);
if (!*inode)
return 1;
return 0;
}
static void modify_u16(char *com, const char *prompt,
const char *format, __u16 *val)
{
char buf[200];
unsigned long v;
char *tmp;
sprintf(buf, format, *val);
printf("%30s [%s] ", prompt, buf);
fgets(buf, sizeof(buf), stdin);
if (buf[strlen (buf) - 1] == '\n')
buf[strlen (buf) - 1] = '\0';
if (!buf[0])
return;
v = strtoul(buf, &tmp, 0);
if (*tmp)
com_err(com, 0, "Bad value - %s", buf);
else
*val = v;
}
static void modify_u32(char *com, const char *prompt,
const char *format, __u32 *val)
{
char buf[200];
unsigned long v;
char *tmp;
sprintf(buf, format, *val);
printf("%30s [%s] ", prompt, buf);
fgets(buf, sizeof(buf), stdin);
if (buf[strlen (buf) - 1] == '\n')
buf[strlen (buf) - 1] = '\0';
if (!buf[0])
return;
v = strtoul(buf, &tmp, 0);
if (*tmp)
com_err(com, 0, "Bad value - %s", buf);
else
*val = v;
}
#define COMMAND_MI "mi"
DLLEXPORT
void do_modify_inode(int readonly, char *filename, unsigned long mode)
{
struct ext2_inode inode;
ext2_ino_t inode_num;
int i;
unsigned char *frag, *fsize;
char buf[80];
int os;
const char *hex_format = "0x%x";
const char *octal_format = "0%o";
const char *decimal_format = "%d";
inode_num = string_to_inode(filename);
if (!inode_num)
return ;
/*
if (common_inode_args_process(argc, argv, &inode_num, CHECK_FS_RW))
return;
*/
os = current_fs->super->s_creator_os;
if (debugfs_read_inode(inode_num, &inode, filename))
return;
printf("Current Mode [0%o] \n", inode.i_mode);
inode.i_mode = mode;
#if 0
modify_u16(COMMAND_MI, "Mode", octal_format, &inode.i_mode);
modify_u16(COMMAND_MI, "User ID", decimal_format, &inode.i_uid);
modify_u16(COMMAND_MI, "Group ID", decimal_format, &inode.i_gid);
modify_u32(COMMAND_MI, "Size", decimal_format, &inode.i_size);
modify_u32(COMMAND_MI, "Creation time", decimal_format, &inode.i_ctime);
modify_u32(COMMAND_MI, "Modification time", decimal_format, &inode.i_mtime);
modify_u32(COMMAND_MI, "Access time", decimal_format, &inode.i_atime);
modify_u32(COMMAND_MI, "Deletion time", decimal_format, &inode.i_dtime);
modify_u16(COMMAND_MI, "Link count", decimal_format, &inode.i_links_count);
modify_u32(COMMAND_MI, "Block count", decimal_format, &inode.i_blocks);
modify_u32(COMMAND_MI, "File flags", hex_format, &inode.i_flags);
modify_u32(COMMAND_MI, "Generation", hex_format, &inode.i_generation);
#if 0
modify_u32(COMMAND_MI, "Reserved1", decimal_format, &inode.i_reserved1);
#endif
modify_u32(COMMAND_MI, "File acl", decimal_format, &inode.i_file_acl);
if (LINUX_S_ISDIR(inode.i_mode))
modify_u32(argv[0], "Directory acl", decimal_format, &inode.i_dir_acl);
else
modify_u32(argv[0], "High 32bits of size", decimal_format, &inode.i_size_high);
if (current_fs->super->s_creator_os == EXT2_OS_HURD)
modify_u32(argv[0], "Translator Block",
decimal_format, &inode.osd1.hurd1.h_i_translator);
modify_u32(argv[0], "Fragment address", decimal_format, &inode.i_faddr);
switch (os) {
case EXT2_OS_LINUX:
frag = &inode.osd2.linux2.l_i_frag;
fsize = &inode.osd2.linux2.l_i_fsize;
break;
case EXT2_OS_HURD:
frag = &inode.osd2.hurd2.h_i_frag;
fsize = &inode.osd2.hurd2.h_i_fsize;
break;
case EXT2_OS_MASIX:
frag = &inode.osd2.masix2.m_i_frag;
fsize = &inode.osd2.masix2.m_i_fsize;
break;
default:
frag = fsize = 0;
}
if (frag)
modify_u8(argv[0], "Fragment number", decimal_format, frag);
if (fsize)
modify_u8(argv[0], "Fragment size", decimal_format, fsize);
for (i=0; i < EXT2_NDIR_BLOCKS; i++) {
sprintf(buf, "Direct Block #%d", i);
modify_u32(argv[0], buf, decimal_format, &inode.i_block[i]);
}
modify_u32(argv[0], "Indirect Block", decimal_format,
&inode.i_block[EXT2_IND_BLOCK]);
modify_u32(argv[0], "Double Indirect Block", decimal_format,
&inode.i_block[EXT2_DIND_BLOCK]);
modify_u32(argv[0], "Triple Indirect Block", decimal_format,
&inode.i_block[EXT2_TIND_BLOCK]);
#endif
if (readonly)
return;
if (debugfs_write_inode(inode_num, &inode, filename))
return;
}
/*
* This function will convert a string to an unsigned long, printing
* an error message if it fails, and returning success or failure in err.
*/
unsigned long parse_ulong(const char *str, const char *cmd,
const char *descr, int *err)
{
char *tmp;
unsigned long ret;
ret = strtoul(str, &tmp, 0);
if (*tmp == 0) {
if (err)
*err = 0;
return ret;
}
com_err(cmd, 0, "Bad %s - %s", descr, str);
if (err)
*err = 1;
else
exit(1);
return 0;
}
/*
* This function will convert a string to a block number. It returns
* 0 on success, 1 on failure.
*/
int strtoblk(const char *cmd, const char *str, blk_t *ret)
{
blk_t blk;
int err;
blk = parse_ulong(str, cmd, "block number", &err);
*ret = blk;
if (err == 0 && blk == 0) {
com_err(cmd, 0, "Invalid block number 0");
err = 1;
}
return err;
}
#ifdef MOD_EXE
int main(int argc, char **argv)
{
int catastrophic = 0;
blk_t superblock = 0;
blk_t blocksize = 0;
int open_flags = 0;
char *file_path = NULL;
char *dev_path = NULL;
int c = 0;
const char *usage = "Usage: chmod [-b blocksize] [-s superblock] [-f file] [-F] [-V] [-c] [-i] [-r] [-o device]";
unsigned long mode;
char *tmp = NULL;
int readonly = 0;
open_flags |= EXT2_FLAG_RW;
while ((c = getopt (argc, argv, "icRF:f:b:s:o:Vr")) != EOF) {
switch (c) {
case 'F':
open_flags |= EXT2_FLAG_FORCE;
break;
case 'f':
file_path = optarg;
break;
case 'i':
open_flags |= EXT2_FLAG_IMAGE_FILE;
break;
case 'o':
dev_path = optarg;
break;
case 'b':
blocksize = parse_ulong(optarg, argv[0],
"block size", 0);
break;
case 's':
superblock = parse_ulong(optarg, argv[0],
"superblock number", 0);
break;
case 'c':
catastrophic = 1;
break;
case 'r':
readonly = 1;
break;
case 'V':
/* Print version number and exit */
fprintf(stderr, "\tUsing %s\n",
error_message(EXT2_ET_BASE));
exit(0);
default:
com_err(argv[0], 0, usage);
return 1;
}
}
if (!file_path || !dev_path || (!readonly && !argv[optind])){
com_err(argv[0], 0, usage);
return 1;
}
if (!readonly) {
printf("Change Mode [%s] \n", argv[optind]);
mode = strtoul(argv[optind], &tmp, 0);
if (*tmp){
com_err(argv[0], 0, "Bad Mode value - %s", argv[optind]);
return 1;
}
}
open_filesystem(dev_path, open_flags,
superblock, blocksize, catastrophic);
if (!current_fs){
return 1;
}
do_modify_inode(readonly, file_path, mode);
close_filesystem();
return 0;
}
#endif

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参考:
e2fsprogs
MinGW
Msys

cjc123123 · 发表于 2015-2-9 22:28:50

谢谢分享。。。。。

[分享] ext2文件系统中inode属性修改