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u-boot/fs/ext4/ext4_common.c
Mikhail Ilin 04e6332ec0 fs: ext4: Fix free(NULL) 
The 'depth_dirname', 'ptr', 'parent_inode' and 'first_inode' pointers
may be null. Thus, it is necessary to check them before using free() to
avoid free(NULL) cases.

Fixes: 934b14f2bb ("ext4: free allocations by parse_path()")
Signed-off-by: Mikhail Ilin <ilin.mikhail.ol@gmail.com>
2022-12-08 09:28:31 -05:00

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// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2011 - 2012 Samsung Electronics
* EXT4 filesystem implementation in Uboot by
* Uma Shankar <uma.shankar@samsung.com>
* Manjunatha C Achar <a.manjunatha@samsung.com>
*
* ext4ls and ext4load : Based on ext2 ls load support in Uboot.
*
* (C) Copyright 2004
* esd gmbh <www.esd-electronics.com>
* Reinhard Arlt <reinhard.arlt@esd-electronics.com>
*
* based on code from grub2 fs/ext2.c and fs/fshelp.c by
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
*
* ext4write : Based on generic ext4 protocol.
*/
#include <common.h>
#include <blk.h>
#include <ext_common.h>
#include <ext4fs.h>
#include <log.h>
#include <malloc.h>
#include <memalign.h>
#include <part.h>
#include <stddef.h>
#include <linux/stat.h>
#include <linux/time.h>
#include <asm/byteorder.h>
#include "ext4_common.h"
struct ext2_data *ext4fs_root;
struct ext2fs_node *ext4fs_file;
__le32 *ext4fs_indir1_block;
int ext4fs_indir1_size;
int ext4fs_indir1_blkno = -1;
__le32 *ext4fs_indir2_block;
int ext4fs_indir2_size;
int ext4fs_indir2_blkno = -1;
__le32 *ext4fs_indir3_block;
int ext4fs_indir3_size;
int ext4fs_indir3_blkno = -1;
struct ext2_inode *g_parent_inode;
static int symlinknest;
#if defined(CONFIG_EXT4_WRITE)
struct ext2_block_group *ext4fs_get_group_descriptor
(const struct ext_filesystem *fs, uint32_t bg_idx)
{
return (struct ext2_block_group *)(fs->gdtable + (bg_idx * fs->gdsize));
}
static inline void ext4fs_sb_free_inodes_dec(struct ext2_sblock *sb)
{
sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) - 1);
}
static inline void ext4fs_sb_free_blocks_dec(struct ext2_sblock *sb)
{
uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
free_blocks--;
sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
}
static inline void ext4fs_bg_free_inodes_dec
(struct ext2_block_group *bg, const struct ext_filesystem *fs)
{
uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
if (fs->gdsize == 64)
free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
free_inodes--;
bg->free_inodes = cpu_to_le16(free_inodes & 0xffff);
if (fs->gdsize == 64)
bg->free_inodes_high = cpu_to_le16(free_inodes >> 16);
}
static inline void ext4fs_bg_free_blocks_dec
(struct ext2_block_group *bg, const struct ext_filesystem *fs)
{
uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
if (fs->gdsize == 64)
free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
free_blocks--;
bg->free_blocks = cpu_to_le16(free_blocks & 0xffff);
if (fs->gdsize == 64)
bg->free_blocks_high = cpu_to_le16(free_blocks >> 16);
}
static inline void ext4fs_bg_itable_unused_dec
(struct ext2_block_group *bg, const struct ext_filesystem *fs)
{
uint32_t free_inodes = le16_to_cpu(bg->bg_itable_unused);
if (fs->gdsize == 64)
free_inodes += le16_to_cpu(bg->bg_itable_unused_high) << 16;
free_inodes--;
bg->bg_itable_unused = cpu_to_le16(free_inodes & 0xffff);
if (fs->gdsize == 64)
bg->bg_itable_unused_high = cpu_to_le16(free_inodes >> 16);
}
uint64_t ext4fs_sb_get_free_blocks(const struct ext2_sblock *sb)
{
uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
return free_blocks;
}
void ext4fs_sb_set_free_blocks(struct ext2_sblock *sb, uint64_t free_blocks)
{
sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
}
uint32_t ext4fs_bg_get_free_blocks(const struct ext2_block_group *bg,
const struct ext_filesystem *fs)
{
uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
if (fs->gdsize == 64)
free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
return free_blocks;
}
static inline
uint32_t ext4fs_bg_get_free_inodes(const struct ext2_block_group *bg,
const struct ext_filesystem *fs)
{
uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
if (fs->gdsize == 64)
free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
return free_inodes;
}
static inline uint16_t ext4fs_bg_get_flags(const struct ext2_block_group *bg)
{
return le16_to_cpu(bg->bg_flags);
}
static inline void ext4fs_bg_set_flags(struct ext2_block_group *bg,
uint16_t flags)
{
bg->bg_flags = cpu_to_le16(flags);
}
/* Block number of the block bitmap */
uint64_t ext4fs_bg_get_block_id(const struct ext2_block_group *bg,
const struct ext_filesystem *fs)
{
uint64_t block_nr = le32_to_cpu(bg->block_id);
if (fs->gdsize == 64)
block_nr += (uint64_t)le32_to_cpu(bg->block_id_high) << 32;
return block_nr;
}
/* Block number of the inode bitmap */
uint64_t ext4fs_bg_get_inode_id(const struct ext2_block_group *bg,
const struct ext_filesystem *fs)
{
uint64_t block_nr = le32_to_cpu(bg->inode_id);
if (fs->gdsize == 64)
block_nr += (uint64_t)le32_to_cpu(bg->inode_id_high) << 32;
return block_nr;
}
#endif
/* Block number of the inode table */
uint64_t ext4fs_bg_get_inode_table_id(const struct ext2_block_group *bg,
const struct ext_filesystem *fs)
{
uint64_t block_nr = le32_to_cpu(bg->inode_table_id);
if (fs->gdsize == 64)
block_nr +=
(uint64_t)le32_to_cpu(bg->inode_table_id_high) << 32;
return block_nr;
}
#if defined(CONFIG_EXT4_WRITE)
uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
{
uint32_t res = size / n;
if (res * n != size)
res++;
return res;
}
void put_ext4(uint64_t off, const void *buf, uint32_t size)
{
uint64_t startblock;
uint64_t remainder;
unsigned char *temp_ptr = NULL;
struct ext_filesystem *fs = get_fs();
int log2blksz = fs->dev_desc->log2blksz;
ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
startblock = off >> log2blksz;
startblock += part_offset;
remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
if (fs->dev_desc == NULL)
return;
if ((startblock + (size >> log2blksz)) >
(part_offset + fs->total_sect)) {
printf("part_offset is " LBAFU "\n", part_offset);
printf("total_sector is %llu\n", fs->total_sect);
printf("error: overflow occurs\n");
return;
}
if (remainder) {
blk_dread(fs->dev_desc, startblock, 1, sec_buf);
temp_ptr = sec_buf;
memcpy((temp_ptr + remainder), (unsigned char *)buf, size);
blk_dwrite(fs->dev_desc, startblock, 1, sec_buf);
} else {
if (size >> log2blksz != 0) {
blk_dwrite(fs->dev_desc, startblock, size >> log2blksz,
(unsigned long *)buf);
} else {
blk_dread(fs->dev_desc, startblock, 1, sec_buf);
temp_ptr = sec_buf;
memcpy(temp_ptr, buf, size);
blk_dwrite(fs->dev_desc, startblock, 1,
(unsigned long *)sec_buf);
}
}
}
static int _get_new_inode_no(unsigned char *buffer)
{
struct ext_filesystem *fs = get_fs();
unsigned char input;
int operand, status;
int count = 1;
int j = 0;
/* get the blocksize of the filesystem */
unsigned char *ptr = buffer;
while (*ptr == 255) {
ptr++;
count += 8;
if (count > le32_to_cpu(ext4fs_root->sblock.inodes_per_group))
return -1;
}
for (j = 0; j < fs->blksz; j++) {
input = *ptr;
int i = 0;
while (i <= 7) {
operand = 1 << i;
status = input & operand;
if (status) {
i++;
count++;
} else {
*ptr |= operand;
return count;
}
}
ptr = ptr + 1;
}
return -1;
}
static int _get_new_blk_no(unsigned char *buffer)
{
int operand;
int count = 0;
int i;
unsigned char *ptr = buffer;
struct ext_filesystem *fs = get_fs();
while (*ptr == 255) {
ptr++;
count += 8;
if (count == (fs->blksz * 8))
return -1;
}
if (fs->blksz == 1024)
count += 1;
for (i = 0; i <= 7; i++) {
operand = 1 << i;
if (*ptr & operand) {
count++;
} else {
*ptr |= operand;
return count;
}
}
return -1;
}
int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
{
int i, remainder, status;
unsigned char *ptr = buffer;
unsigned char operand;
i = blockno / 8;
remainder = blockno % 8;
int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
i = i - (index * blocksize);
if (blocksize != 1024) {
ptr = ptr + i;
operand = 1 << remainder;
status = *ptr & operand;
if (status)
return -1;
*ptr = *ptr | operand;
return 0;
} else {
if (remainder == 0) {
ptr = ptr + i - 1;
operand = (1 << 7);
} else {
ptr = ptr + i;
operand = (1 << (remainder - 1));
}
status = *ptr & operand;
if (status)
return -1;
*ptr = *ptr | operand;
return 0;
}
}
void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
{
int i, remainder, status;
unsigned char *ptr = buffer;
unsigned char operand;
i = blockno / 8;
remainder = blockno % 8;
int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
i = i - (index * blocksize);
if (blocksize != 1024) {
ptr = ptr + i;
operand = (1 << remainder);
status = *ptr & operand;
if (status)
*ptr = *ptr & ~(operand);
} else {
if (remainder == 0) {
ptr = ptr + i - 1;
operand = (1 << 7);
} else {
ptr = ptr + i;
operand = (1 << (remainder - 1));
}
status = *ptr & operand;
if (status)
*ptr = *ptr & ~(operand);
}
}
int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
{
int i, remainder, status;
unsigned char *ptr = buffer;
unsigned char operand;
inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
i = inode_no / 8;
remainder = inode_no % 8;
if (remainder == 0) {
ptr = ptr + i - 1;
operand = (1 << 7);
} else {
ptr = ptr + i;
operand = (1 << (remainder - 1));
}
status = *ptr & operand;
if (status)
return -1;
*ptr = *ptr | operand;
return 0;
}
void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
{
int i, remainder, status;
unsigned char *ptr = buffer;
unsigned char operand;
inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
i = inode_no / 8;
remainder = inode_no % 8;
if (remainder == 0) {
ptr = ptr + i - 1;
operand = (1 << 7);
} else {
ptr = ptr + i;
operand = (1 << (remainder - 1));
}
status = *ptr & operand;
if (status)
*ptr = *ptr & ~(operand);
}
uint16_t ext4fs_checksum_update(uint32_t i)
{
struct ext2_block_group *desc;
struct ext_filesystem *fs = get_fs();
uint16_t crc = 0;
__le32 le32_i = cpu_to_le32(i);
desc = ext4fs_get_group_descriptor(fs, i);
if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
int offset = offsetof(struct ext2_block_group, bg_checksum);
crc = crc16(~0, (__u8 *)fs->sb->unique_id,
sizeof(fs->sb->unique_id));
crc = crc16(crc, (__u8 *)&le32_i, sizeof(le32_i));
crc = crc16(crc, (__u8 *)desc, offset);
offset += sizeof(desc->bg_checksum); /* skip checksum */
assert(offset == sizeof(*desc));
if (offset < fs->gdsize) {
crc = crc16(crc, (__u8 *)desc + offset,
fs->gdsize - offset);
}
}
return crc;
}
static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
{
int dentry_length;
int sizeof_void_space;
int new_entry_byte_reqd;
short padding_factor = 0;
if (dir->namelen % 4 != 0)
padding_factor = 4 - (dir->namelen % 4);
dentry_length = sizeof(struct ext2_dirent) +
dir->namelen + padding_factor;
sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length;
if (sizeof_void_space == 0)
return 0;
padding_factor = 0;
if (strlen(filename) % 4 != 0)
padding_factor = 4 - (strlen(filename) % 4);
new_entry_byte_reqd = strlen(filename) +
sizeof(struct ext2_dirent) + padding_factor;
if (sizeof_void_space >= new_entry_byte_reqd) {
dir->direntlen = cpu_to_le16(dentry_length);
return sizeof_void_space;
}
return 0;
}
int ext4fs_update_parent_dentry(char *filename, int file_type)
{
unsigned int *zero_buffer = NULL;
char *root_first_block_buffer = NULL;
int blk_idx;
long int first_block_no_of_root = 0;
int totalbytes = 0;
unsigned int new_entry_byte_reqd;
int sizeof_void_space = 0;
int templength = 0;
int inodeno = -1;
int status;
struct ext_filesystem *fs = get_fs();
/* directory entry */
struct ext2_dirent *dir;
char *temp_dir = NULL;
uint32_t new_blk_no;
uint32_t new_size;
uint32_t new_blockcnt;
uint32_t directory_blocks;
zero_buffer = zalloc(fs->blksz);
if (!zero_buffer) {
printf("No Memory\n");
return -1;
}
root_first_block_buffer = zalloc(fs->blksz);
if (!root_first_block_buffer) {
free(zero_buffer);
printf("No Memory\n");
return -1;
}
new_entry_byte_reqd = ROUND(strlen(filename) +
sizeof(struct ext2_dirent), 4);
restart:
directory_blocks = le32_to_cpu(g_parent_inode->size) >>
LOG2_BLOCK_SIZE(ext4fs_root);
blk_idx = directory_blocks - 1;
restart_read:
/* read the block no allocated to a file */
first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx,
NULL);
if (first_block_no_of_root <= 0)
goto fail;
status = ext4fs_devread((lbaint_t)first_block_no_of_root
* fs->sect_perblk,
0, fs->blksz, root_first_block_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
goto fail;
dir = (struct ext2_dirent *)root_first_block_buffer;
totalbytes = 0;
while (le16_to_cpu(dir->direntlen) > 0) {
unsigned short used_len = ROUND(dir->namelen +
sizeof(struct ext2_dirent), 4);
/* last entry of block */
if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) {
/* check if new entry fits */
if ((used_len + new_entry_byte_reqd) <=
le16_to_cpu(dir->direntlen)) {
dir->direntlen = cpu_to_le16(used_len);
break;
} else {
if (blk_idx > 0) {
printf("Block full, trying previous\n");
blk_idx--;
goto restart_read;
}
printf("All blocks full: Allocate new\n");
if (le32_to_cpu(g_parent_inode->flags) &
EXT4_EXTENTS_FL) {
printf("Directory uses extents\n");
goto fail;
}
if (directory_blocks >= INDIRECT_BLOCKS) {
printf("Directory exceeds limit\n");
goto fail;
}
new_blk_no = ext4fs_get_new_blk_no();
if (new_blk_no == -1) {
printf("no block left to assign\n");
goto fail;
}
put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz);
g_parent_inode->b.blocks.
dir_blocks[directory_blocks] =
cpu_to_le32(new_blk_no);
new_size = le32_to_cpu(g_parent_inode->size);
new_size += fs->blksz;
g_parent_inode->size = cpu_to_le32(new_size);
new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt);
new_blockcnt += fs->blksz >> LOG2_SECTOR_SIZE;
g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt);
if (ext4fs_put_metadata
(root_first_block_buffer,
first_block_no_of_root))
goto fail;
goto restart;
}
}
templength = le16_to_cpu(dir->direntlen);
totalbytes = totalbytes + templength;
sizeof_void_space = check_void_in_dentry(dir, filename);
if (sizeof_void_space)
break;
dir = (struct ext2_dirent *)((char *)dir + templength);
}
/* make a pointer ready for creating next directory entry */
templength = le16_to_cpu(dir->direntlen);
totalbytes = totalbytes + templength;
dir = (struct ext2_dirent *)((char *)dir + templength);
/* get the next available inode number */
inodeno = ext4fs_get_new_inode_no();
if (inodeno == -1) {
printf("no inode left to assign\n");
goto fail;
}
dir->inode = cpu_to_le32(inodeno);
if (sizeof_void_space)
dir->direntlen = cpu_to_le16(sizeof_void_space);
else
dir->direntlen = cpu_to_le16(fs->blksz - totalbytes);
dir->namelen = strlen(filename);
dir->filetype = file_type;
temp_dir = (char *)dir;
temp_dir = temp_dir + sizeof(struct ext2_dirent);
memcpy(temp_dir, filename, strlen(filename));
/* update or write the 1st block of root inode */
if (ext4fs_put_metadata(root_first_block_buffer,
first_block_no_of_root))
goto fail;
fail:
free(zero_buffer);
free(root_first_block_buffer);
return inodeno;
}
static int search_dir(struct ext2_inode *parent_inode, char *dirname)
{
int status;
int inodeno = 0;
int offset;
int blk_idx;
long int blknr;
char *block_buffer = NULL;
struct ext2_dirent *dir = NULL;
struct ext_filesystem *fs = get_fs();
uint32_t directory_blocks;
char *direntname;
directory_blocks = le32_to_cpu(parent_inode->size) >>
LOG2_BLOCK_SIZE(ext4fs_root);
block_buffer = zalloc(fs->blksz);
if (!block_buffer)
goto fail;
/* get the block no allocated to a file */
for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
blknr = read_allocated_block(parent_inode, blk_idx, NULL);
if (blknr <= 0)
goto fail;
/* read the directory block */
status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
0, fs->blksz, (char *)block_buffer);
if (status == 0)
goto fail;
offset = 0;
do {
if (offset & 3) {
printf("Badly aligned ext2_dirent\n");
break;
}
dir = (struct ext2_dirent *)(block_buffer + offset);
direntname = (char*)(dir) + sizeof(struct ext2_dirent);
int direntlen = le16_to_cpu(dir->direntlen);
if (direntlen < sizeof(struct ext2_dirent))
break;
if (dir->inode && (strlen(dirname) == dir->namelen) &&
(strncmp(dirname, direntname, dir->namelen) == 0)) {
inodeno = le32_to_cpu(dir->inode);
break;
}
offset += direntlen;
} while (offset < fs->blksz);
if (inodeno > 0) {
free(block_buffer);
return inodeno;
}
}
fail:
free(block_buffer);
return -1;
}
static int find_dir_depth(char *dirname)
{
char *token = strtok(dirname, "/");
int count = 0;
while (token != NULL) {
token = strtok(NULL, "/");
count++;
}
return count + 1 + 1;
/*
* for example for string /home/temp
* depth=home(1)+temp(1)+1 extra for NULL;
* so count is 4;
*/
}
static int parse_path(char **arr, char *dirname)
{
char *token = strtok(dirname, "/");
int i = 0;
/* add root */
arr[i] = zalloc(strlen("/") + 1);
if (!arr[i])
return -ENOMEM;
memcpy(arr[i++], "/", strlen("/"));
/* add each path entry after root */
while (token != NULL) {
arr[i] = zalloc(strlen(token) + 1);
if (!arr[i])
return -ENOMEM;
memcpy(arr[i++], token, strlen(token));
token = strtok(NULL, "/");
}
arr[i] = NULL;
return 0;
}
int ext4fs_iget(int inode_no, struct ext2_inode *inode)
{
if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
return -1;
return 0;
}
/*
* Function: ext4fs_get_parent_inode_num
* Return Value: inode Number of the parent directory of file/Directory to be
* created
* dirname : Input parmater, input path name of the file/directory to be created
* dname : Output parameter, to be filled with the name of the directory
* extracted from dirname
*/
int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
{
int i;
int depth = 0;
int matched_inode_no;
int result_inode_no = -1;
char **ptr = NULL;
char *depth_dirname = NULL;
char *parse_dirname = NULL;
struct ext2_inode *parent_inode = NULL;
struct ext2_inode *first_inode = NULL;
struct ext2_inode temp_inode;
if (*dirname != '/') {
printf("Please supply Absolute path\n");
return -1;
}
/* TODO: input validation make equivalent to linux */
depth_dirname = zalloc(strlen(dirname) + 1);
if (!depth_dirname)
return -ENOMEM;
memcpy(depth_dirname, dirname, strlen(dirname));
depth = find_dir_depth(depth_dirname);
parse_dirname = zalloc(strlen(dirname) + 1);
if (!parse_dirname)
goto fail;
memcpy(parse_dirname, dirname, strlen(dirname));
/* allocate memory for each directory level */
ptr = zalloc((depth) * sizeof(char *));
if (!ptr)
goto fail;
if (parse_path(ptr, parse_dirname))
goto fail;
parent_inode = zalloc(sizeof(struct ext2_inode));
if (!parent_inode)
goto fail;
first_inode = zalloc(sizeof(struct ext2_inode));
if (!first_inode)
goto fail;
memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
if (flags & F_FILE)
result_inode_no = EXT2_ROOT_INO;
for (i = 1; i < depth; i++) {
matched_inode_no = search_dir(parent_inode, ptr[i]);
if (matched_inode_no == -1) {
if (ptr[i + 1] == NULL && i == 1) {
result_inode_no = EXT2_ROOT_INO;
goto end;
} else {
if (ptr[i + 1] == NULL)
break;
printf("Invalid path\n");
result_inode_no = -1;
goto fail;
}
} else {
if (ptr[i + 1] != NULL) {
memset(parent_inode, '\0',
sizeof(struct ext2_inode));
if (ext4fs_iget(matched_inode_no,
parent_inode)) {
result_inode_no = -1;
goto fail;
}
result_inode_no = matched_inode_no;
} else {
break;
}
}
}
end:
if (i == 1)
matched_inode_no = search_dir(first_inode, ptr[i]);
else
matched_inode_no = search_dir(parent_inode, ptr[i]);
if (matched_inode_no != -1) {
ext4fs_iget(matched_inode_no, &temp_inode);
if (le16_to_cpu(temp_inode.mode) & S_IFDIR) {
printf("It is a Directory\n");
result_inode_no = -1;
goto fail;
}
}
if (strlen(ptr[i]) > 256) {
result_inode_no = -1;
goto fail;
}
memcpy(dname, ptr[i], strlen(ptr[i]));
fail:
free(depth_dirname);
if (parse_dirname)
free(parse_dirname);
if (ptr) {
for (i = 0; i < depth; i++) {
if (!ptr[i])
break;
free(ptr[i]);
}
free(ptr);
}
if (parent_inode)
free(parent_inode);
if (first_inode)
free(first_inode);
return result_inode_no;
}
static int unlink_filename(char *filename, unsigned int blknr)
{
int status;
int inodeno = 0;
int offset;
char *block_buffer = NULL;
struct ext2_dirent *dir = NULL;
struct ext2_dirent *previous_dir;
struct ext_filesystem *fs = get_fs();
int ret = -1;
char *direntname;
block_buffer = zalloc(fs->blksz);
if (!block_buffer)
return -ENOMEM;
/* read the directory block */
status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
fs->blksz, block_buffer);
if (status == 0)
goto fail;
offset = 0;
do {
if (offset & 3) {
printf("Badly aligned ext2_dirent\n");
break;
}
previous_dir = dir;
dir = (struct ext2_dirent *)(block_buffer + offset);
direntname = (char *)(dir) + sizeof(struct ext2_dirent);
int direntlen = le16_to_cpu(dir->direntlen);
if (direntlen < sizeof(struct ext2_dirent))
break;
if (dir->inode && (strlen(filename) == dir->namelen) &&
(strncmp(direntname, filename, dir->namelen) == 0)) {
inodeno = le32_to_cpu(dir->inode);
break;
}
offset += direntlen;
} while (offset < fs->blksz);
if (inodeno > 0) {
printf("file found, deleting\n");
if (ext4fs_log_journal(block_buffer, blknr))
goto fail;
if (previous_dir) {
/* merge dir entry with predecessor */
uint16_t new_len;
new_len = le16_to_cpu(previous_dir->direntlen);
new_len += le16_to_cpu(dir->direntlen);
previous_dir->direntlen = cpu_to_le16(new_len);
} else {
/* invalidate dir entry */
dir->inode = 0;
}
if (ext4fs_put_metadata(block_buffer, blknr))
goto fail;
ret = inodeno;
}
fail:
free(block_buffer);
return ret;
}
int ext4fs_filename_unlink(char *filename)
{
int blk_idx;
long int blknr = -1;
int inodeno = -1;
uint32_t directory_blocks;
directory_blocks = le32_to_cpu(g_parent_inode->size) >>
LOG2_BLOCK_SIZE(ext4fs_root);
/* read the block no allocated to a file */
for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
blknr = read_allocated_block(g_parent_inode, blk_idx, NULL);
if (blknr <= 0)
break;
inodeno = unlink_filename(filename, blknr);
if (inodeno != -1)
return inodeno;
}
return -1;
}
uint32_t ext4fs_get_new_blk_no(void)
{
short i;
short status;
int remainder;
unsigned int bg_idx;
static int prev_bg_bitmap_index = -1;
unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
struct ext_filesystem *fs = get_fs();
char *journal_buffer = zalloc(fs->blksz);
char *zero_buffer = zalloc(fs->blksz);
if (!journal_buffer || !zero_buffer)
goto fail;
if (fs->first_pass_bbmap == 0) {
for (i = 0; i < fs->no_blkgrp; i++) {
struct ext2_block_group *bgd = NULL;
bgd = ext4fs_get_group_descriptor(fs, i);
if (ext4fs_bg_get_free_blocks(bgd, fs)) {
uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
uint64_t b_bitmap_blk =
ext4fs_bg_get_block_id(bgd, fs);
if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
memcpy(fs->blk_bmaps[i], zero_buffer,
fs->blksz);
put_ext4(b_bitmap_blk * fs->blksz,
fs->blk_bmaps[i], fs->blksz);
bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
ext4fs_bg_set_flags(bgd, bg_flags);
}
fs->curr_blkno =
_get_new_blk_no(fs->blk_bmaps[i]);
if (fs->curr_blkno == -1)
/* block bitmap is completely filled */
continue;
fs->curr_blkno = fs->curr_blkno +
(i * fs->blksz * 8);
fs->first_pass_bbmap++;
ext4fs_bg_free_blocks_dec(bgd, fs);
ext4fs_sb_free_blocks_dec(fs->sb);
status = ext4fs_devread(b_bitmap_blk *
fs->sect_perblk,
0, fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
b_bitmap_blk))
goto fail;
goto success;
} else {
debug("no space left on block group %d\n", i);
}
}
goto fail;
} else {
fs->curr_blkno++;
restart:
/* get the blockbitmap index respective to blockno */
bg_idx = fs->curr_blkno / blk_per_grp;
if (fs->blksz == 1024) {
remainder = fs->curr_blkno % blk_per_grp;
if (!remainder)
bg_idx--;
}
/*
* To skip completely filled block group bitmaps
* Optimize the block allocation
*/
if (bg_idx >= fs->no_blkgrp)
goto fail;
struct ext2_block_group *bgd = NULL;
bgd = ext4fs_get_group_descriptor(fs, bg_idx);
if (ext4fs_bg_get_free_blocks(bgd, fs) == 0) {
debug("block group %u is full. Skipping\n", bg_idx);
fs->curr_blkno = (bg_idx + 1) * blk_per_grp;
if (fs->blksz == 1024)
fs->curr_blkno += 1;
goto restart;
}
uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
put_ext4(b_bitmap_blk * fs->blksz,
zero_buffer, fs->blksz);
bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
ext4fs_bg_set_flags(bgd, bg_flags);
}
if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
bg_idx) != 0) {
debug("going for restart for the block no %ld %u\n",
fs->curr_blkno, bg_idx);
fs->curr_blkno++;
goto restart;
}
/* journal backup */
if (prev_bg_bitmap_index != bg_idx) {
status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
0, fs->blksz, journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
goto fail;
prev_bg_bitmap_index = bg_idx;
}
ext4fs_bg_free_blocks_dec(bgd, fs);
ext4fs_sb_free_blocks_dec(fs->sb);
goto success;
}
success:
free(journal_buffer);
free(zero_buffer);
return fs->curr_blkno;
fail:
free(journal_buffer);
free(zero_buffer);
return -1;
}
int ext4fs_get_new_inode_no(void)
{
short i;
short status;
unsigned int ibmap_idx;
static int prev_inode_bitmap_index = -1;
unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
struct ext_filesystem *fs = get_fs();
char *journal_buffer = zalloc(fs->blksz);
char *zero_buffer = zalloc(fs->blksz);
if (!journal_buffer || !zero_buffer)
goto fail;
int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) &
EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0;
if (fs->first_pass_ibmap == 0) {
for (i = 0; i < fs->no_blkgrp; i++) {
uint32_t free_inodes;
struct ext2_block_group *bgd = NULL;
bgd = ext4fs_get_group_descriptor(fs, i);
free_inodes = ext4fs_bg_get_free_inodes(bgd, fs);
if (free_inodes) {
uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
uint64_t i_bitmap_blk =
ext4fs_bg_get_inode_id(bgd, fs);
if (has_gdt_chksum)
bgd->bg_itable_unused = free_inodes;
if (bg_flags & EXT4_BG_INODE_UNINIT) {
put_ext4(i_bitmap_blk * fs->blksz,
zero_buffer, fs->blksz);
bg_flags &= ~EXT4_BG_INODE_UNINIT;
ext4fs_bg_set_flags(bgd, bg_flags);
memcpy(fs->inode_bmaps[i],
zero_buffer, fs->blksz);
}
fs->curr_inode_no =
_get_new_inode_no(fs->inode_bmaps[i]);
if (fs->curr_inode_no == -1)
/* inode bitmap is completely filled */
continue;
fs->curr_inode_no = fs->curr_inode_no +
(i * inodes_per_grp);
fs->first_pass_ibmap++;
ext4fs_bg_free_inodes_dec(bgd, fs);
if (has_gdt_chksum)
ext4fs_bg_itable_unused_dec(bgd, fs);
ext4fs_sb_free_inodes_dec(fs->sb);
status = ext4fs_devread(i_bitmap_blk *
fs->sect_perblk,
0, fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
i_bitmap_blk))
goto fail;
goto success;
} else
debug("no inode left on block group %d\n", i);
}
goto fail;
} else {
restart:
fs->curr_inode_no++;
/* get the blockbitmap index respective to blockno */
ibmap_idx = fs->curr_inode_no / inodes_per_grp;
struct ext2_block_group *bgd =
ext4fs_get_group_descriptor(fs, ibmap_idx);
uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
uint64_t i_bitmap_blk = ext4fs_bg_get_inode_id(bgd, fs);
if (bg_flags & EXT4_BG_INODE_UNINIT) {
put_ext4(i_bitmap_blk * fs->blksz,
zero_buffer, fs->blksz);
bg_flags &= ~EXT4_BG_INODE_UNINIT;
ext4fs_bg_set_flags(bgd, bg_flags);
memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
fs->blksz);
}
if (ext4fs_set_inode_bmap(fs->curr_inode_no,
fs->inode_bmaps[ibmap_idx],
ibmap_idx) != 0) {
debug("going for restart for the block no %d %u\n",
fs->curr_inode_no, ibmap_idx);
goto restart;
}
/* journal backup */
if (prev_inode_bitmap_index != ibmap_idx) {
status = ext4fs_devread(i_bitmap_blk * fs->sect_perblk,
0, fs->blksz, journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
le32_to_cpu(bgd->inode_id)))
goto fail;
prev_inode_bitmap_index = ibmap_idx;
}
ext4fs_bg_free_inodes_dec(bgd, fs);
if (has_gdt_chksum)
bgd->bg_itable_unused = bgd->free_inodes;
ext4fs_sb_free_inodes_dec(fs->sb);
goto success;
}
success:
free(journal_buffer);
free(zero_buffer);
return fs->curr_inode_no;
fail:
free(journal_buffer);
free(zero_buffer);
return -1;
}
static void alloc_single_indirect_block(struct ext2_inode *file_inode,
unsigned int *total_remaining_blocks,
unsigned int *no_blks_reqd)
{
short i;
short status;
long int actual_block_no;
long int si_blockno;
/* si :single indirect */
__le32 *si_buffer = NULL;
__le32 *si_start_addr = NULL;
struct ext_filesystem *fs = get_fs();
if (*total_remaining_blocks != 0) {
si_buffer = zalloc(fs->blksz);
if (!si_buffer) {
printf("No Memory\n");
return;
}
si_start_addr = si_buffer;
si_blockno = ext4fs_get_new_blk_no();
if (si_blockno == -1) {
printf("no block left to assign\n");
goto fail;
}
(*no_blks_reqd)++;
debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
0, fs->blksz, (char *)si_buffer);
memset(si_buffer, '\0', fs->blksz);
if (status == 0)
goto fail;
for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
actual_block_no = ext4fs_get_new_blk_no();
if (actual_block_no == -1) {
printf("no block left to assign\n");
goto fail;
}
*si_buffer = cpu_to_le32(actual_block_no);
debug("SIAB %u: %u\n", *si_buffer,
*total_remaining_blocks);
si_buffer++;
(*total_remaining_blocks)--;
if (*total_remaining_blocks == 0)
break;
}
/* write the block to disk */
put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
si_start_addr, fs->blksz);
file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
}
fail:
free(si_start_addr);
}
static void alloc_double_indirect_block(struct ext2_inode *file_inode,
unsigned int *total_remaining_blocks,
unsigned int *no_blks_reqd)
{
short i;
short j;
short status;
long int actual_block_no;
/* di:double indirect */
long int di_blockno_parent;
long int di_blockno_child;
__le32 *di_parent_buffer = NULL;
__le32 *di_child_buff = NULL;
__le32 *di_block_start_addr = NULL;
__le32 *di_child_buff_start = NULL;
struct ext_filesystem *fs = get_fs();
if (*total_remaining_blocks != 0) {
/* double indirect parent block connecting to inode */
di_blockno_parent = ext4fs_get_new_blk_no();
if (di_blockno_parent == -1) {
printf("no block left to assign\n");
goto fail;
}
di_parent_buffer = zalloc(fs->blksz);
if (!di_parent_buffer)
goto fail;
di_block_start_addr = di_parent_buffer;
(*no_blks_reqd)++;
debug("DIPB %ld: %u\n", di_blockno_parent,
*total_remaining_blocks);
status = ext4fs_devread((lbaint_t)di_blockno_parent *
fs->sect_perblk, 0,
fs->blksz, (char *)di_parent_buffer);
if (!status) {
printf("%s: Device read error!\n", __func__);
goto fail;
}
memset(di_parent_buffer, '\0', fs->blksz);
/*
* start:for each double indirect parent
* block create one more block
*/
for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
di_blockno_child = ext4fs_get_new_blk_no();
if (di_blockno_child == -1) {
printf("no block left to assign\n");
goto fail;
}
di_child_buff = zalloc(fs->blksz);
if (!di_child_buff)
goto fail;
di_child_buff_start = di_child_buff;
*di_parent_buffer = cpu_to_le32(di_blockno_child);
di_parent_buffer++;
(*no_blks_reqd)++;
debug("DICB %ld: %u\n", di_blockno_child,
*total_remaining_blocks);
status = ext4fs_devread((lbaint_t)di_blockno_child *
fs->sect_perblk, 0,
fs->blksz,
(char *)di_child_buff);
if (!status) {
printf("%s: Device read error!\n", __func__);
goto fail;
}
memset(di_child_buff, '\0', fs->blksz);
/* filling of actual datablocks for each child */
for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
actual_block_no = ext4fs_get_new_blk_no();
if (actual_block_no == -1) {
printf("no block left to assign\n");
goto fail;
}
*di_child_buff = cpu_to_le32(actual_block_no);
debug("DIAB %ld: %u\n", actual_block_no,
*total_remaining_blocks);
di_child_buff++;
(*total_remaining_blocks)--;
if (*total_remaining_blocks == 0)
break;
}
/* write the block table */
put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
di_child_buff_start, fs->blksz);
free(di_child_buff_start);
di_child_buff_start = NULL;
if (*total_remaining_blocks == 0)
break;
}
put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
di_block_start_addr, fs->blksz);
file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
}
fail:
free(di_block_start_addr);
}
static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
unsigned int *total_remaining_blocks,
unsigned int *no_blks_reqd)
{
short i;
short j;
short k;
long int actual_block_no;
/* ti: Triple Indirect */
long int ti_gp_blockno;
long int ti_parent_blockno;
long int ti_child_blockno;
__le32 *ti_gp_buff = NULL;
__le32 *ti_parent_buff = NULL;
__le32 *ti_child_buff = NULL;
__le32 *ti_gp_buff_start_addr = NULL;
__le32 *ti_pbuff_start_addr = NULL;
__le32 *ti_cbuff_start_addr = NULL;
struct ext_filesystem *fs = get_fs();
if (*total_remaining_blocks != 0) {
/* triple indirect grand parent block connecting to inode */
ti_gp_blockno = ext4fs_get_new_blk_no();
if (ti_gp_blockno == -1) {
printf("no block left to assign\n");
return;
}
ti_gp_buff = zalloc(fs->blksz);
if (!ti_gp_buff)
return;
ti_gp_buff_start_addr = ti_gp_buff;
(*no_blks_reqd)++;
debug("TIGPB %ld: %u\n", ti_gp_blockno,
*total_remaining_blocks);
/* for each 4 byte grand parent entry create one more block */
for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
ti_parent_blockno = ext4fs_get_new_blk_no();
if (ti_parent_blockno == -1) {
printf("no block left to assign\n");
goto fail;
}
ti_parent_buff = zalloc(fs->blksz);
if (!ti_parent_buff)
goto fail;
ti_pbuff_start_addr = ti_parent_buff;
*ti_gp_buff = cpu_to_le32(ti_parent_blockno);
ti_gp_buff++;
(*no_blks_reqd)++;
debug("TIPB %ld: %u\n", ti_parent_blockno,
*total_remaining_blocks);
/* for each 4 byte entry parent create one more block */
for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
ti_child_blockno = ext4fs_get_new_blk_no();
if (ti_child_blockno == -1) {
printf("no block left assign\n");
goto fail1;
}
ti_child_buff = zalloc(fs->blksz);
if (!ti_child_buff)
goto fail1;
ti_cbuff_start_addr = ti_child_buff;
*ti_parent_buff = cpu_to_le32(ti_child_blockno);
ti_parent_buff++;
(*no_blks_reqd)++;
debug("TICB %ld: %u\n", ti_parent_blockno,
*total_remaining_blocks);
/* fill actual datablocks for each child */
for (k = 0; k < (fs->blksz / sizeof(int));
k++) {
actual_block_no =
ext4fs_get_new_blk_no();
if (actual_block_no == -1) {
printf("no block left\n");
free(ti_cbuff_start_addr);
goto fail1;
}
*ti_child_buff = cpu_to_le32(actual_block_no);
debug("TIAB %ld: %u\n", actual_block_no,
*total_remaining_blocks);
ti_child_buff++;
(*total_remaining_blocks)--;
if (*total_remaining_blocks == 0)
break;
}
/* write the child block */
put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
(uint64_t)fs->blksz)),
ti_cbuff_start_addr, fs->blksz);
free(ti_cbuff_start_addr);
if (*total_remaining_blocks == 0)
break;
}
/* write the parent block */
put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
ti_pbuff_start_addr, fs->blksz);
free(ti_pbuff_start_addr);
if (*total_remaining_blocks == 0)
break;
}
/* write the grand parent block */
put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
ti_gp_buff_start_addr, fs->blksz);
file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
free(ti_gp_buff_start_addr);
return;
}
fail1:
free(ti_pbuff_start_addr);
fail:
free(ti_gp_buff_start_addr);
}
void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
unsigned int total_remaining_blocks,
unsigned int *total_no_of_block)
{
short i;
long int direct_blockno;
unsigned int no_blks_reqd = 0;
/* allocation of direct blocks */
for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
direct_blockno = ext4fs_get_new_blk_no();
if (direct_blockno == -1) {
printf("no block left to assign\n");
return;
}
file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
total_remaining_blocks--;
}
alloc_single_indirect_block(file_inode, &total_remaining_blocks,
&no_blks_reqd);
alloc_double_indirect_block(file_inode, &total_remaining_blocks,
&no_blks_reqd);
alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
&no_blks_reqd);
*total_no_of_block += no_blks_reqd;
}
#endif
static struct ext4_extent_header *ext4fs_get_extent_block
(struct ext2_data *data, struct ext_block_cache *cache,
struct ext4_extent_header *ext_block,
uint32_t fileblock, int log2_blksz)
{
struct ext4_extent_idx *index;
unsigned long long block;
int blksz = EXT2_BLOCK_SIZE(data);
int i;
while (1) {
index = (struct ext4_extent_idx *)(ext_block + 1);
if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
return NULL;
if (ext_block->eh_depth == 0)
return ext_block;
i = -1;
do {
i++;
if (i >= le16_to_cpu(ext_block->eh_entries))
break;
} while (fileblock >= le32_to_cpu(index[i].ei_block));
/*
* If first logical block number is higher than requested fileblock,
* it is a sparse file. This is handled on upper layer.
*/
if (i > 0)
i--;
block = le16_to_cpu(index[i].ei_leaf_hi);
block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
block <<= log2_blksz;
if (!ext_cache_read(cache, (lbaint_t)block, blksz))
return NULL;
ext_block = (struct ext4_extent_header *)cache->buf;
}
}
static int ext4fs_blockgroup
(struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
{
long int blkno;
unsigned int blkoff, desc_per_blk;
int log2blksz = get_fs()->dev_desc->log2blksz;
int desc_size = get_fs()->gdsize;
if (desc_size == 0)
return 0;
desc_per_blk = EXT2_BLOCK_SIZE(data) / desc_size;
if (desc_per_blk == 0)
return 0;
blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
group / desc_per_blk;
blkoff = (group % desc_per_blk) * desc_size;
debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
group, blkno, blkoff);
return ext4fs_devread((lbaint_t)blkno <<
(LOG2_BLOCK_SIZE(data) - log2blksz),
blkoff, desc_size, (char *)blkgrp);
}
int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
{
struct ext2_block_group *blkgrp;
struct ext2_sblock *sblock = &data->sblock;
struct ext_filesystem *fs = get_fs();
int log2blksz = get_fs()->dev_desc->log2blksz;
int inodes_per_block, status;
long int blkno;
unsigned int blkoff;
/* Allocate blkgrp based on gdsize (for 64-bit support). */
blkgrp = zalloc(get_fs()->gdsize);
if (!blkgrp)
return 0;
/* It is easier to calculate if the first inode is 0. */
ino--;
if ( le32_to_cpu(sblock->inodes_per_group) == 0 || fs->inodesz == 0) {
free(blkgrp);
return 0;
}
status = ext4fs_blockgroup(data, ino / le32_to_cpu
(sblock->inodes_per_group), blkgrp);
if (status == 0) {
free(blkgrp);
return 0;
}
inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
if ( inodes_per_block == 0 ) {
free(blkgrp);
return 0;
}
blkno = ext4fs_bg_get_inode_table_id(blkgrp, fs) +
(ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
blkoff = (ino % inodes_per_block) * fs->inodesz;
/* Free blkgrp as it is no longer required. */
free(blkgrp);
/* Read the inode. */
status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
log2blksz), blkoff,
sizeof(struct ext2_inode), (char *)inode);
if (status == 0)
return 0;
return 1;
}
long int read_allocated_block(struct ext2_inode *inode, int fileblock,
struct ext_block_cache *cache)
{
long int blknr;
int blksz;
int log2_blksz;
int status;
long int rblock;
long int perblock_parent;
long int perblock_child;
unsigned long long start;
/* get the blocksize of the filesystem */
blksz = EXT2_BLOCK_SIZE(ext4fs_root);
log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
- get_fs()->dev_desc->log2blksz;
if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
long int startblock, endblock;
struct ext_block_cache *c, cd;
struct ext4_extent_header *ext_block;
struct ext4_extent *extent;
int i;
if (cache) {
c = cache;
} else {
c = &cd;
ext_cache_init(c);
}
ext_block =
ext4fs_get_extent_block(ext4fs_root, c,
(struct ext4_extent_header *)
inode->b.blocks.dir_blocks,
fileblock, log2_blksz);
if (!ext_block) {
printf("invalid extent block\n");
if (!cache)
ext_cache_fini(c);
return -EINVAL;
}
extent = (struct ext4_extent *)(ext_block + 1);
for (i = 0; i < le16_to_cpu(ext_block->eh_entries); i++) {
startblock = le32_to_cpu(extent[i].ee_block);
endblock = startblock + le16_to_cpu(extent[i].ee_len);
if (startblock > fileblock) {
/* Sparse file */
if (!cache)
ext_cache_fini(c);
return 0;
} else if (fileblock < endblock) {
start = le16_to_cpu(extent[i].ee_start_hi);
start = (start << 32) +
le32_to_cpu(extent[i].ee_start_lo);
if (!cache)
ext_cache_fini(c);
return (fileblock - startblock) + start;
}
}
if (!cache)
ext_cache_fini(c);
return 0;
}
/* Direct blocks. */
if (fileblock < INDIRECT_BLOCKS)
blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
/* Indirect. */
else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
if (ext4fs_indir1_block == NULL) {
ext4fs_indir1_block = zalloc(blksz);
if (ext4fs_indir1_block == NULL) {
printf("** SI ext2fs read block (indir 1)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir1_size = blksz;
ext4fs_indir1_blkno = -1;
}
if (blksz != ext4fs_indir1_size) {
free(ext4fs_indir1_block);
ext4fs_indir1_block = NULL;
ext4fs_indir1_size = 0;
ext4fs_indir1_blkno = -1;
ext4fs_indir1_block = zalloc(blksz);
if (ext4fs_indir1_block == NULL) {
printf("** SI ext2fs read block (indir 1):"
"malloc failed. **\n");
return -1;
}
ext4fs_indir1_size = blksz;
}
if ((le32_to_cpu(inode->b.blocks.indir_block) <<
log2_blksz) != ext4fs_indir1_blkno) {
status =
ext4fs_devread((lbaint_t)le32_to_cpu
(inode->b.blocks.
indir_block) << log2_blksz, 0,
blksz, (char *)ext4fs_indir1_block);
if (status == 0) {
printf("** SI ext2fs read block (indir 1)"
"failed. **\n");
return -1;
}
ext4fs_indir1_blkno =
le32_to_cpu(inode->b.blocks.
indir_block) << log2_blksz;
}
blknr = le32_to_cpu(ext4fs_indir1_block
[fileblock - INDIRECT_BLOCKS]);
}
/* Double indirect. */
else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
(blksz / 4 + 1)))) {
long int perblock = blksz / 4;
long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
if (ext4fs_indir1_block == NULL) {
ext4fs_indir1_block = zalloc(blksz);
if (ext4fs_indir1_block == NULL) {
printf("** DI ext2fs read block (indir 2 1)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir1_size = blksz;
ext4fs_indir1_blkno = -1;
}
if (blksz != ext4fs_indir1_size) {
free(ext4fs_indir1_block);
ext4fs_indir1_block = NULL;
ext4fs_indir1_size = 0;
ext4fs_indir1_blkno = -1;
ext4fs_indir1_block = zalloc(blksz);
if (ext4fs_indir1_block == NULL) {
printf("** DI ext2fs read block (indir 2 1)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir1_size = blksz;
}
if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
log2_blksz) != ext4fs_indir1_blkno) {
status =
ext4fs_devread((lbaint_t)le32_to_cpu
(inode->b.blocks.
double_indir_block) << log2_blksz,
0, blksz,
(char *)ext4fs_indir1_block);
if (status == 0) {
printf("** DI ext2fs read block (indir 2 1)"
"failed. **\n");
return -1;
}
ext4fs_indir1_blkno =
le32_to_cpu(inode->b.blocks.double_indir_block) <<
log2_blksz;
}
if (ext4fs_indir2_block == NULL) {
ext4fs_indir2_block = zalloc(blksz);
if (ext4fs_indir2_block == NULL) {
printf("** DI ext2fs read block (indir 2 2)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir2_size = blksz;
ext4fs_indir2_blkno = -1;
}
if (blksz != ext4fs_indir2_size) {
free(ext4fs_indir2_block);
ext4fs_indir2_block = NULL;
ext4fs_indir2_size = 0;
ext4fs_indir2_blkno = -1;
ext4fs_indir2_block = zalloc(blksz);
if (ext4fs_indir2_block == NULL) {
printf("** DI ext2fs read block (indir 2 2)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir2_size = blksz;
}
if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
log2_blksz) != ext4fs_indir2_blkno) {
status = ext4fs_devread((lbaint_t)le32_to_cpu
(ext4fs_indir1_block
[rblock /
perblock]) << log2_blksz, 0,
blksz,
(char *)ext4fs_indir2_block);
if (status == 0) {
printf("** DI ext2fs read block (indir 2 2)"
"failed. **\n");
return -1;
}
ext4fs_indir2_blkno =
le32_to_cpu(ext4fs_indir1_block[rblock
/
perblock]) <<
log2_blksz;
}
blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
}
/* Tripple indirect. */
else {
rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
(blksz / 4 * blksz / 4));
perblock_child = blksz / 4;
perblock_parent = ((blksz / 4) * (blksz / 4));
if (ext4fs_indir1_block == NULL) {
ext4fs_indir1_block = zalloc(blksz);
if (ext4fs_indir1_block == NULL) {
printf("** TI ext2fs read block (indir 2 1)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir1_size = blksz;
ext4fs_indir1_blkno = -1;
}
if (blksz != ext4fs_indir1_size) {
free(ext4fs_indir1_block);
ext4fs_indir1_block = NULL;
ext4fs_indir1_size = 0;
ext4fs_indir1_blkno = -1;
ext4fs_indir1_block = zalloc(blksz);
if (ext4fs_indir1_block == NULL) {
printf("** TI ext2fs read block (indir 2 1)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir1_size = blksz;
}
if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
log2_blksz) != ext4fs_indir1_blkno) {
status = ext4fs_devread
((lbaint_t)
le32_to_cpu(inode->b.blocks.triple_indir_block)
<< log2_blksz, 0, blksz,
(char *)ext4fs_indir1_block);
if (status == 0) {
printf("** TI ext2fs read block (indir 2 1)"
"failed. **\n");
return -1;
}
ext4fs_indir1_blkno =
le32_to_cpu(inode->b.blocks.triple_indir_block) <<
log2_blksz;
}
if (ext4fs_indir2_block == NULL) {
ext4fs_indir2_block = zalloc(blksz);
if (ext4fs_indir2_block == NULL) {
printf("** TI ext2fs read block (indir 2 2)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir2_size = blksz;
ext4fs_indir2_blkno = -1;
}
if (blksz != ext4fs_indir2_size) {
free(ext4fs_indir2_block);
ext4fs_indir2_block = NULL;
ext4fs_indir2_size = 0;
ext4fs_indir2_blkno = -1;
ext4fs_indir2_block = zalloc(blksz);
if (ext4fs_indir2_block == NULL) {
printf("** TI ext2fs read block (indir 2 2)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir2_size = blksz;
}
if ((le32_to_cpu(ext4fs_indir1_block[rblock /
perblock_parent]) <<
log2_blksz)
!= ext4fs_indir2_blkno) {
status = ext4fs_devread((lbaint_t)le32_to_cpu
(ext4fs_indir1_block
[rblock /
perblock_parent]) <<
log2_blksz, 0, blksz,
(char *)ext4fs_indir2_block);
if (status == 0) {
printf("** TI ext2fs read block (indir 2 2)"
"failed. **\n");
return -1;
}
ext4fs_indir2_blkno =
le32_to_cpu(ext4fs_indir1_block[rblock /
perblock_parent])
<< log2_blksz;
}
if (ext4fs_indir3_block == NULL) {
ext4fs_indir3_block = zalloc(blksz);
if (ext4fs_indir3_block == NULL) {
printf("** TI ext2fs read block (indir 2 2)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir3_size = blksz;
ext4fs_indir3_blkno = -1;
}
if (blksz != ext4fs_indir3_size) {
free(ext4fs_indir3_block);
ext4fs_indir3_block = NULL;
ext4fs_indir3_size = 0;
ext4fs_indir3_blkno = -1;
ext4fs_indir3_block = zalloc(blksz);
if (ext4fs_indir3_block == NULL) {
printf("** TI ext2fs read block (indir 2 2)"
"malloc failed. **\n");
return -1;
}
ext4fs_indir3_size = blksz;
}
if ((le32_to_cpu(ext4fs_indir2_block[rblock
/
perblock_child]) <<
log2_blksz) != ext4fs_indir3_blkno) {
status =
ext4fs_devread((lbaint_t)le32_to_cpu
(ext4fs_indir2_block
[(rblock / perblock_child)
% (blksz / 4)]) << log2_blksz, 0,
blksz, (char *)ext4fs_indir3_block);
if (status == 0) {
printf("** TI ext2fs read block (indir 2 2)"
"failed. **\n");
return -1;
}
ext4fs_indir3_blkno =
le32_to_cpu(ext4fs_indir2_block[(rblock /
perblock_child) %
(blksz /
4)]) <<
log2_blksz;
}
blknr = le32_to_cpu(ext4fs_indir3_block
[rblock % perblock_child]);
}
debug("read_allocated_block %ld\n", blknr);
return blknr;
}
/**
* ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
* global pointers
*
* This function assures that for a file with the same name but different size
* the sequential store on the ext4 filesystem will be correct.
*
* In this function the global data, responsible for internal representation
* of the ext4 data are initialized to the reset state. Without this, during
* replacement of the smaller file with the bigger truncation of new file was
* performed.
*/
void ext4fs_reinit_global(void)
{
if (ext4fs_indir1_block != NULL) {
free(ext4fs_indir1_block);
ext4fs_indir1_block = NULL;
ext4fs_indir1_size = 0;
ext4fs_indir1_blkno = -1;
}
if (ext4fs_indir2_block != NULL) {
free(ext4fs_indir2_block);
ext4fs_indir2_block = NULL;
ext4fs_indir2_size = 0;
ext4fs_indir2_blkno = -1;
}
if (ext4fs_indir3_block != NULL) {
free(ext4fs_indir3_block);
ext4fs_indir3_block = NULL;
ext4fs_indir3_size = 0;
ext4fs_indir3_blkno = -1;
}
}
void ext4fs_close(void)
{
if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
ext4fs_file = NULL;
}
if (ext4fs_root != NULL) {
free(ext4fs_root);
ext4fs_root = NULL;
}
ext4fs_reinit_global();
}
int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
struct ext2fs_node **fnode, int *ftype)
{
unsigned int fpos = 0;
int status;
loff_t actread;
struct ext2fs_node *diro = (struct ext2fs_node *) dir;
#ifdef DEBUG
if (name != NULL)
printf("Iterate dir %s\n", name);
#endif /* of DEBUG */
if (!diro->inode_read) {
status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
if (status == 0)
return 0;
}
/* Search the file. */
while (fpos < le32_to_cpu(diro->inode.size)) {
struct ext2_dirent dirent;
status = ext4fs_read_file(diro, fpos,
sizeof(struct ext2_dirent),
(char *)&dirent, &actread);
if (status < 0)
return 0;
if (dirent.direntlen == 0) {
printf("Failed to iterate over directory %s\n", name);
return 0;
}
if (dirent.namelen != 0) {
char filename[dirent.namelen + 1];
struct ext2fs_node *fdiro;
int type = FILETYPE_UNKNOWN;
status = ext4fs_read_file(diro,
fpos +
sizeof(struct ext2_dirent),
dirent.namelen, filename,
&actread);
if (status < 0)
return 0;
fdiro = zalloc(sizeof(struct ext2fs_node));
if (!fdiro)
return 0;
fdiro->data = diro->data;
fdiro->ino = le32_to_cpu(dirent.inode);
filename[dirent.namelen] = '\0';
if (dirent.filetype != FILETYPE_UNKNOWN) {
fdiro->inode_read = 0;
if (dirent.filetype == FILETYPE_DIRECTORY)
type = FILETYPE_DIRECTORY;
else if (dirent.filetype == FILETYPE_SYMLINK)
type = FILETYPE_SYMLINK;
else if (dirent.filetype == FILETYPE_REG)
type = FILETYPE_REG;
} else {
status = ext4fs_read_inode(diro->data,
le32_to_cpu
(dirent.inode),
&fdiro->inode);
if (status == 0) {
free(fdiro);
return 0;
}
fdiro->inode_read = 1;
if ((le16_to_cpu(fdiro->inode.mode) &
FILETYPE_INO_MASK) ==
FILETYPE_INO_DIRECTORY) {
type = FILETYPE_DIRECTORY;
} else if ((le16_to_cpu(fdiro->inode.mode)
& FILETYPE_INO_MASK) ==
FILETYPE_INO_SYMLINK) {
type = FILETYPE_SYMLINK;
} else if ((le16_to_cpu(fdiro->inode.mode)
& FILETYPE_INO_MASK) ==
FILETYPE_INO_REG) {
type = FILETYPE_REG;
}
}
#ifdef DEBUG
printf("iterate >%s<\n", filename);
#endif /* of DEBUG */
if ((name != NULL) && (fnode != NULL)
&& (ftype != NULL)) {
if (strcmp(filename, name) == 0) {
*ftype = type;
*fnode = fdiro;
return 1;
}
} else {
if (fdiro->inode_read == 0) {
status = ext4fs_read_inode(diro->data,
le32_to_cpu(
dirent.inode),
&fdiro->inode);
if (status == 0) {
free(fdiro);
return 0;
}
fdiro->inode_read = 1;
}
switch (type) {
case FILETYPE_DIRECTORY:
printf("<DIR> ");
break;
case FILETYPE_SYMLINK:
printf("<SYM> ");
break;
case FILETYPE_REG:
printf(" ");
break;
default:
printf("< ? > ");
break;
}
printf("%10u %s\n",
le32_to_cpu(fdiro->inode.size),
filename);
}
free(fdiro);
}
fpos += le16_to_cpu(dirent.direntlen);
}
return 0;
}
static char *ext4fs_read_symlink(struct ext2fs_node *node)
{
char *symlink;
struct ext2fs_node *diro = node;
int status;
loff_t actread;
if (!diro->inode_read) {
status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
if (status == 0)
return NULL;
}
symlink = zalloc(le32_to_cpu(diro->inode.size) + 1);
if (!symlink)
return NULL;
if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) {
strncpy(symlink, diro->inode.b.symlink,
le32_to_cpu(diro->inode.size));
} else {
status = ext4fs_read_file(diro, 0,
le32_to_cpu(diro->inode.size),
symlink, &actread);
if ((status < 0) || (actread == 0)) {
free(symlink);
return NULL;
}
}
symlink[le32_to_cpu(diro->inode.size)] = '\0';
return symlink;
}
static int ext4fs_find_file1(const char *currpath,
struct ext2fs_node *currroot,
struct ext2fs_node **currfound, int *foundtype)
{
char fpath[strlen(currpath) + 1];
char *name = fpath;
char *next;
int status;
int type = FILETYPE_DIRECTORY;
struct ext2fs_node *currnode = currroot;
struct ext2fs_node *oldnode = currroot;
strncpy(fpath, currpath, strlen(currpath) + 1);
/* Remove all leading slashes. */
while (*name == '/')
name++;
if (!*name) {
*currfound = currnode;
return 1;
}
for (;;) {
int found;
/* Extract the actual part from the pathname. */
next = strchr(name, '/');
if (next) {
/* Remove all leading slashes. */
while (*next == '/')
*(next++) = '\0';
}
if (type != FILETYPE_DIRECTORY) {
ext4fs_free_node(currnode, currroot);
return 0;
}
oldnode = currnode;
/* Iterate over the directory. */
found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
if (found == 0)
return 0;
if (found == -1)
break;
/* Read in the symlink and follow it. */
if (type == FILETYPE_SYMLINK) {
char *symlink;
/* Test if the symlink does not loop. */
if (++symlinknest == 8) {
ext4fs_free_node(currnode, currroot);
ext4fs_free_node(oldnode, currroot);
return 0;
}
symlink = ext4fs_read_symlink(currnode);
ext4fs_free_node(currnode, currroot);
if (!symlink) {
ext4fs_free_node(oldnode, currroot);
return 0;
}
debug("Got symlink >%s<\n", symlink);
if (symlink[0] == '/') {
ext4fs_free_node(oldnode, currroot);
oldnode = &ext4fs_root->diropen;
}
/* Lookup the node the symlink points to. */
status = ext4fs_find_file1(symlink, oldnode,
&currnode, &type);
free(symlink);
if (status == 0) {
ext4fs_free_node(oldnode, currroot);
return 0;
}
}
ext4fs_free_node(oldnode, currroot);
/* Found the node! */
if (!next || *next == '\0') {
*currfound = currnode;
*foundtype = type;
return 1;
}
name = next;
}
return -1;
}
int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
struct ext2fs_node **foundnode, int expecttype)
{
int status;
int foundtype = FILETYPE_DIRECTORY;
symlinknest = 0;
if (!path)
return 0;
status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
if (status == 0)
return 0;
/* Check if the node that was found was of the expected type. */
if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
return 0;
else if ((expecttype == FILETYPE_DIRECTORY)
&& (foundtype != expecttype))
return 0;
return 1;
}
int ext4fs_open(const char *filename, loff_t *len)
{
struct ext2fs_node *fdiro = NULL;
int status;
if (ext4fs_root == NULL)
return -1;
ext4fs_file = NULL;
status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
FILETYPE_REG);
if (status == 0)
goto fail;
if (!fdiro->inode_read) {
status = ext4fs_read_inode(fdiro->data, fdiro->ino,
&fdiro->inode);
if (status == 0)
goto fail;
}
*len = le32_to_cpu(fdiro->inode.size);
ext4fs_file = fdiro;
return 0;
fail:
ext4fs_free_node(fdiro, &ext4fs_root->diropen);
return -1;
}
int ext4fs_mount(unsigned part_length)
{
struct ext2_data *data;
int status;
struct ext_filesystem *fs = get_fs();
data = zalloc(SUPERBLOCK_SIZE);
if (!data)
return 0;
/* Read the superblock. */
status = ext4_read_superblock((char *)&data->sblock);
if (status == 0)
goto fail;
/* Make sure this is an ext2 filesystem. */
if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
goto fail_noerr;
if (le32_to_cpu(data->sblock.revision_level) == 0) {
fs->inodesz = 128;
fs->gdsize = 32;
} else {
debug("EXT4 features COMPAT: %08x INCOMPAT: %08x RO_COMPAT: %08x\n",
__le32_to_cpu(data->sblock.feature_compatibility),
__le32_to_cpu(data->sblock.feature_incompat),
__le32_to_cpu(data->sblock.feature_ro_compat));
fs->inodesz = le16_to_cpu(data->sblock.inode_size);
fs->gdsize = le32_to_cpu(data->sblock.feature_incompat) &
EXT4_FEATURE_INCOMPAT_64BIT ?
le16_to_cpu(data->sblock.descriptor_size) : 32;
}
debug("EXT2 rev %d, inode_size %d, descriptor size %d\n",
le32_to_cpu(data->sblock.revision_level),
fs->inodesz, fs->gdsize);
data->diropen.data = data;
data->diropen.ino = 2;
data->diropen.inode_read = 1;
data->inode = &data->diropen.inode;
status = ext4fs_read_inode(data, 2, data->inode);
if (status == 0)
goto fail;
ext4fs_root = data;
return 1;
fail:
log_debug("Failed to mount ext2 filesystem...\n");
fail_noerr:
free(data);
ext4fs_root = NULL;
return 0;
}
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