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-rw-r--r--hostTools/squashfs/read_fs.c498
1 files changed, 498 insertions, 0 deletions
diff --git a/hostTools/squashfs/read_fs.c b/hostTools/squashfs/read_fs.c
new file mode 100644
index 0000000..cdb62a7
--- /dev/null
+++ b/hostTools/squashfs/read_fs.c
@@ -0,0 +1,498 @@
+/*
+ * Read a squashfs filesystem. This is a highly compressed read only filesystem.
+ *
+ * Copyright (c) 2002, 2003, 2004 Phillip Lougher <plougher@users.sourceforge.net>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * read_fs.c
+ */
+
+extern void read_bytes(int, unsigned int, int, char *);
+extern int add_file(int, int, unsigned int *, int, unsigned int, int, int);
+
+#define TRUE 1
+#define FALSE 0
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <zlib.h>
+#include <sys/mman.h>
+
+#include <endian.h>
+#include "read_fs.h"
+#include <squashfs_fs.h>
+
+#include <stdlib.h>
+
+#ifdef SQUASHFS_TRACE
+#define TRACE(s, args...) printf("mksquashfs: "s, ## args)
+#else
+#define TRACE(s, args...)
+#endif
+
+#define ERROR(s, args...) fprintf(stderr, s, ## args)
+
+int swap;
+
+int read_block(int fd, int start, int *next, unsigned char *block, squashfs_super_block *sBlk)
+{
+ unsigned short c_byte;
+ int offset = 2;
+
+ if(swap) {
+ read_bytes(fd, start, 2, block);
+ ((unsigned char *) &c_byte)[1] = block[0];
+ ((unsigned char *) &c_byte)[0] = block[1];
+ } else
+ read_bytes(fd, start, 2, (char *)&c_byte);
+
+ if(SQUASHFS_CHECK_DATA(sBlk->flags))
+ offset = 3;
+ if(SQUASHFS_COMPRESSED(c_byte)) {
+ unsigned char buffer[SQUASHFS_METADATA_SIZE];
+ int res;
+ long bytes = SQUASHFS_METADATA_SIZE;
+
+ c_byte = SQUASHFS_COMPRESSED_SIZE(c_byte);
+ read_bytes(fd, start + offset, c_byte, buffer);
+
+ if((res = uncompress(block, &bytes, (const char *) buffer, c_byte)) != Z_OK) {
+ if(res == Z_MEM_ERROR)
+ ERROR("zlib::uncompress failed, not enough memory\n");
+ else if(res == Z_BUF_ERROR)
+ ERROR("zlib::uncompress failed, not enough room in output buffer\n");
+ else
+ ERROR("zlib::uncompress failed, unknown error %d\n", res);
+ return 0;
+ }
+ if(next)
+ *next = start + offset + c_byte;
+ return bytes;
+ } else {
+ c_byte = SQUASHFS_COMPRESSED_SIZE(c_byte);
+ read_bytes(fd, start + offset, c_byte, block);
+ if(next)
+ *next = start + offset + c_byte;
+ return c_byte;
+ }
+}
+
+
+int scan_inode_table(int fd, int start, int end, int root_inode_start, squashfs_super_block *sBlk,
+ squashfs_dir_inode_header *dir_inode, unsigned char **inode_table, unsigned int *root_inode_block,
+ unsigned int *uncompressed_file, unsigned int *uncompressed_directory, int *file_count, int *sym_count,
+ int *dev_count, int *dir_count, int *fifo_count, int *sock_count)
+{
+ unsigned char *cur_ptr;
+ int bytes = 0, size = 0, files = 0;
+ squashfs_reg_inode_header inode;
+ unsigned int directory_start_block;
+
+ TRACE("scan_inode_table: start 0x%x, end 0x%x, root_inode_start 0x%x\n", start, end, root_inode_start);
+ while(start < end) {
+ if(start == root_inode_start) {
+ TRACE("scan_inode_table: read compressed block 0x%x containing root inode\n", start);
+ *root_inode_block = bytes;
+ }
+ if((size - bytes < SQUASHFS_METADATA_SIZE) &&
+ ((*inode_table = realloc(*inode_table, size += SQUASHFS_METADATA_SIZE)) == NULL))
+ return FALSE;
+ TRACE("scan_inode_table: reading block 0x%x\n", start);
+ if((bytes += read_block(fd, start, &start, *inode_table + bytes, sBlk)) == 0) {
+ free(*inode_table);
+ return FALSE;
+ }
+ }
+
+ /*
+ * Read last inode entry which is the root directory inode, and obtain the last
+ * directory start block index. This is used when calculating the total uncompressed
+ * directory size. The directory bytes in the last block will be counted as normal.
+ *
+ * The root inode is ignored in the inode scan. This ensures there is
+ * always enough bytes left to read a regular file inode entry
+ */
+ bytes -= sizeof(squashfs_dir_inode_header);
+ if(swap) {
+ squashfs_dir_inode_header sinode;
+ memcpy((void *)&sinode, (void *)(*inode_table + bytes), sizeof(*dir_inode));
+ SQUASHFS_SWAP_DIR_INODE_HEADER(dir_inode, &sinode);
+ } else
+ memcpy((void *)dir_inode, (void *)(*inode_table + bytes), sizeof(*dir_inode));
+ directory_start_block = dir_inode->start_block;
+
+ for(cur_ptr = *inode_table; cur_ptr < *inode_table + bytes; files ++) {
+ if(swap) {
+ squashfs_reg_inode_header sinode;
+ memcpy((void *)&sinode, (void *)cur_ptr, sizeof(inode));
+ SQUASHFS_SWAP_REG_INODE_HEADER(&inode, &sinode);
+ } else
+ memcpy((void *)&inode, (void *)cur_ptr, sizeof(inode));
+
+ TRACE("scan_inode_table: processing inode @ byte position 0x%x, type 0x%x\n", cur_ptr - *inode_table,
+ inode.inode_type);
+ switch(inode.inode_type) {
+ case SQUASHFS_FILE_TYPE: {
+ int frag_bytes = inode.fragment == SQUASHFS_INVALID_BLK ? 0 : inode.file_size % sBlk->block_size;
+ int blocks = inode.fragment == SQUASHFS_INVALID_BLK ? (inode.file_size
+ + sBlk->block_size - 1) >> sBlk->block_log : inode.file_size >>
+ sBlk->block_log;
+ int file_bytes = 0, i, start = inode.start_block;
+ unsigned int block_list[blocks];
+
+ TRACE("scan_inode_table: regular file, file_size %d, blocks %d\n", inode.file_size, blocks);
+
+ cur_ptr += sizeof(inode);
+ if(swap) {
+ unsigned int sblock_list[blocks];
+ memcpy((void *)sblock_list, (void *)cur_ptr, blocks * sizeof(unsigned int));
+ SQUASHFS_SWAP_INTS(block_list, sblock_list, blocks);
+ } else
+ memcpy((void *)block_list, (void *)cur_ptr, blocks * sizeof(unsigned int));
+
+ *uncompressed_file += inode.file_size;
+ (*file_count) ++;
+
+ for(i = 0; i < blocks; i++)
+ file_bytes += SQUASHFS_COMPRESSED_SIZE_BLOCK(block_list[i]);
+
+ add_file(start, file_bytes, block_list, blocks, inode.fragment, inode.offset, frag_bytes);
+ cur_ptr += blocks * sizeof(unsigned int);
+ break;
+ }
+ case SQUASHFS_SYMLINK_TYPE: {
+ squashfs_symlink_inode_header inodep;
+
+ if(swap) {
+ squashfs_symlink_inode_header sinodep;
+ memcpy((void *)&sinodep, (void *)cur_ptr, sizeof(sinodep));
+ SQUASHFS_SWAP_SYMLINK_INODE_HEADER(&inodep, &sinodep);
+ } else
+ memcpy((void *)&inodep, (void *)cur_ptr, sizeof(inodep));
+ (*sym_count) ++;
+ cur_ptr += sizeof(inodep) + inodep.symlink_size;
+ break;
+ }
+ case SQUASHFS_DIR_TYPE: {
+ squashfs_dir_inode_header dir_inode;
+
+ if(swap) {
+ squashfs_dir_inode_header sinode;
+ memcpy((void *)&sinode, (void *)cur_ptr, sizeof(dir_inode));
+ SQUASHFS_SWAP_DIR_INODE_HEADER(&dir_inode, &sinode);
+ } else
+ memcpy((void *)&dir_inode, (void *)cur_ptr, sizeof(dir_inode));
+ if(dir_inode.start_block < directory_start_block)
+ *uncompressed_directory += dir_inode.file_size;
+ (*dir_count) ++;
+ cur_ptr += sizeof(squashfs_dir_inode_header);
+ break;
+ }
+ case SQUASHFS_BLKDEV_TYPE:
+ case SQUASHFS_CHRDEV_TYPE:
+ (*dev_count) ++;
+ cur_ptr += sizeof(squashfs_dev_inode_header);
+ break;
+
+ case SQUASHFS_FIFO_TYPE:
+ (*fifo_count) ++;
+ cur_ptr += sizeof(squashfs_ipc_inode_header);
+ break;
+ case SQUASHFS_SOCKET_TYPE:
+ (*sock_count) ++;
+ cur_ptr += sizeof(squashfs_ipc_inode_header);
+ break;
+ default:
+ ERROR("Unknown inode type %d in scan_inode_table!\n", inode.inode_type);
+ free(*inode_table);
+ return FALSE;
+ }
+ }
+
+ return files;
+}
+
+
+int read_super(int fd, squashfs_super_block *sBlk, int *be, char *source)
+{
+ read_bytes(fd, SQUASHFS_START, sizeof(squashfs_super_block), (char *) sBlk);
+
+ /* Check it is a SQUASHFS superblock */
+ swap = 0;
+ if(sBlk->s_magic != SQUASHFS_MAGIC) {
+ if(sBlk->s_magic == SQUASHFS_MAGIC_SWAP) {
+ squashfs_super_block sblk;
+ ERROR("Reading a different endian SQUASHFS filesystem on %s - ignoring -le/-be options\n", source);
+ SQUASHFS_SWAP_SUPER_BLOCK(&sblk, sBlk);
+ memcpy(sBlk, &sblk, sizeof(squashfs_super_block));
+ swap = 1;
+ } else {
+ ERROR("Can't find a SQUASHFS superblock on %s\n", source);
+ goto failed_mount;
+ }
+ }
+
+ /* Check the MAJOR & MINOR versions */
+ if(sBlk->s_major != SQUASHFS_MAJOR || sBlk->s_minor > SQUASHFS_MINOR) {
+ if(sBlk->s_major == 1)
+ ERROR("Filesystem on %s is a SQUASHFS 1.x filesystem. Appending\nto SQUASHFS 1.x filesystems is not supported. Please convert it to a SQUASHFS 2.0 filesystem...n", source);
+ else
+ ERROR("Major/Minor mismatch, filesystem on %s is (%d:%d), I support (%d: <= %d)\n",
+ source, sBlk->s_major, sBlk->s_minor, SQUASHFS_MAJOR, SQUASHFS_MINOR);
+ goto failed_mount;
+ }
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+ *be = !swap;
+#else
+ *be = swap;
+#endif
+
+ printf("Found a valid SQUASHFS superblock on %s.\n", source);
+ printf("\tInodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(sBlk->flags) ? "un" : "");
+ printf("\tData is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(sBlk->flags) ? "un" : "");
+ printf("\tFragments are %scompressed\n", SQUASHFS_UNCOMPRESSED_FRAGMENTS(sBlk->flags) ? "un" : "");
+ printf("\tCheck data is %s present in the filesystem\n", SQUASHFS_CHECK_DATA(sBlk->flags) ? "" : "not");
+ printf("\tFragments are %s present in the filesystem\n", SQUASHFS_NO_FRAGMENTS(sBlk->flags) ? "not" : "");
+ printf("\tAlways_use_fragments option is %s specified\n", SQUASHFS_ALWAYS_FRAGMENTS(sBlk->flags) ? "" : "not");
+ printf("\tDuplicates are %s removed\n", SQUASHFS_DUPLICATES(sBlk->flags) ? "" : "not");
+ printf("\tFilesystem size %d bytes\n", sBlk->bytes_used);
+ printf("\tBlock size %d\n", sBlk->block_size);
+ printf("\tNumber of fragments %d\n", sBlk->fragments);
+ printf("\tNumber of inodes %d\n", sBlk->inodes);
+ printf("\tNumber of uids %d\n", sBlk->no_uids);
+ printf("\tNumber of gids %d\n", sBlk->no_guids);
+ TRACE("sBlk->inode_table_start %x\n", sBlk->inode_table_start);
+ TRACE("sBlk->directory_table_start %x\n", sBlk->directory_table_start);
+ TRACE("sBlk->uid_start %x\n", sBlk->uid_start);
+ TRACE("sBlk->fragment_table_start %x\n", sBlk->fragment_table_start);
+ printf("\n");
+
+ return TRUE;
+
+failed_mount:
+ return FALSE;
+}
+
+
+unsigned char *squashfs_readdir(int fd, int root_entries, int start, int offset, int size, squashfs_super_block *sBlk,
+ void (push_directory_entry)(char *, squashfs_inode, int))
+{
+ squashfs_dir_header dirh;
+ char buffer[sizeof(squashfs_dir_entry) + SQUASHFS_NAME_LEN + 1];
+ squashfs_dir_entry *dire = (squashfs_dir_entry *) buffer;
+ unsigned char *directory_table = NULL;
+ int bytes = 0, dir_count;
+
+ size += offset;
+ if((directory_table = malloc((size + SQUASHFS_METADATA_SIZE * 2 - 1) & ~(SQUASHFS_METADATA_SIZE - 1))) == NULL)
+ return NULL;
+ while(bytes < size) {
+ TRACE("squashfs_readdir: reading block 0x%x, bytes read so far %d\n", start, bytes);
+ if((bytes += read_block(fd, start, &start, directory_table + bytes, sBlk)) == 0) {
+ free(directory_table);
+ return NULL;
+ }
+ }
+
+ if(!root_entries)
+ goto all_done;
+
+ bytes = offset;
+ while(bytes < size) {
+ if(swap) {
+ squashfs_dir_header sdirh;
+ memcpy((void *)&sdirh, directory_table + bytes, sizeof(sdirh));
+ SQUASHFS_SWAP_DIR_HEADER(&dirh, &sdirh);
+ } else
+ memcpy((void *)&dirh, directory_table + bytes, sizeof(dirh));
+
+ dir_count = dirh.count + 1;
+ TRACE("squashfs_readdir: Read directory header @ byte position 0x%x, 0x%x directory entries\n", bytes, dir_count);
+ bytes += sizeof(dirh);
+
+ while(dir_count--) {
+ if(swap) {
+ squashfs_dir_entry sdire;
+ memcpy((void *)&sdire, directory_table + bytes, sizeof(sdire));
+ SQUASHFS_SWAP_DIR_ENTRY(dire, &sdire);
+ } else
+ memcpy((void *)dire, directory_table + bytes, sizeof(dire));
+ bytes += sizeof(*dire);
+
+ memcpy((void *)dire->name, directory_table + bytes, dire->size + 1);
+ dire->name[dire->size + 1] = '\0';
+ TRACE("squashfs_readdir: pushing directory entry %s, inode %x:%x, type 0x%x\n", dire->name, dirh.start_block, dire->offset, dire->type);
+ push_directory_entry(dire->name, SQUASHFS_MKINODE(dirh.start_block, dire->offset), dire->type);
+ bytes += dire->size + 1;
+ }
+ }
+
+all_done:
+ return directory_table;
+}
+
+
+int read_fragment_table(int fd, squashfs_super_block *sBlk, squashfs_fragment_entry **fragment_table)
+{
+ int i, indexes = SQUASHFS_FRAGMENT_INDEXES(sBlk->fragments);
+ squashfs_fragment_index fragment_table_index[indexes];
+
+ TRACE("read_fragment_table: %d fragments, reading %d fragment indexes from 0x%x\n", sBlk->fragments, indexes, sBlk->fragment_table_start);
+ if(sBlk->fragments == 0)
+ return 1;
+
+ if((*fragment_table = (squashfs_fragment_entry *) malloc(sBlk->fragments * sizeof(squashfs_fragment_entry))) == NULL) {
+ ERROR("Failed to allocate fragment table\n");
+ return 0;
+ }
+
+ if(swap) {
+ squashfs_fragment_index sfragment_table_index[indexes];
+
+ read_bytes(fd, sBlk->fragment_table_start, SQUASHFS_FRAGMENT_INDEX_BYTES(sBlk->fragments), (char *) sfragment_table_index);
+ SQUASHFS_SWAP_FRAGMENT_INDEXES(fragment_table_index, sfragment_table_index, indexes);
+ } else
+ read_bytes(fd, sBlk->fragment_table_start, SQUASHFS_FRAGMENT_INDEX_BYTES(sBlk->fragments), (char *) fragment_table_index);
+
+ for(i = 0; i < indexes; i++) {
+ int length = read_block(fd, fragment_table_index[i], NULL, ((char *) *fragment_table) + (i * SQUASHFS_METADATA_SIZE), sBlk);
+ TRACE("Read fragment table block %d, from 0x%x, length %d\n", i, fragment_table_index[i], length);
+ }
+
+
+ if(swap) {
+ squashfs_fragment_entry sfragment;
+ for(i = 0; i < sBlk->fragments; i++) {
+ SQUASHFS_SWAP_FRAGMENT_ENTRY((&sfragment), (&(*fragment_table)[i]));
+ memcpy((char *) &(*fragment_table)[i], (char *) &sfragment, sizeof(squashfs_fragment_entry));
+ }
+ }
+
+ return 1;
+}
+
+
+int read_filesystem(char *root_name, int fd, squashfs_super_block *sBlk, char **cinode_table, int *inode_bytes,
+ char **data_cache, int *cache_bytes, int *cache_size,
+ char **cdirectory_table, int *directory_bytes,
+ char **directory_data_cache, int *directory_cache_bytes, int *directory_cache_size,
+ int *file_count, int *sym_count, int *dev_count, int *dir_count, int *fifo_count, int *sock_count,
+ squashfs_uid *uids, unsigned short *uid_count, squashfs_uid *guids, unsigned short *guid_count,
+ unsigned int *uncompressed_file, unsigned int *uncompressed_inode, unsigned int *uncompressed_directory,
+ void (push_directory_entry)(char *, squashfs_inode, int), squashfs_fragment_entry **fragment_table)
+{
+ unsigned char *inode_table = NULL, *directory_table;
+ unsigned int start = sBlk->inode_table_start, end = sBlk->directory_table_start,
+ root_inode_start = start + SQUASHFS_INODE_BLK(sBlk->root_inode),
+ root_inode_offset = SQUASHFS_INODE_OFFSET(sBlk->root_inode), root_directory_offset;
+ squashfs_dir_inode_header inode;
+ unsigned int files, root_inode_block;
+
+ printf("Scanning existing filesystem...\n");
+
+ if(read_fragment_table(fd, sBlk, fragment_table) == 0)
+ goto error;
+
+ if((files = scan_inode_table(fd, start, end, root_inode_start, sBlk, &inode, &inode_table, &root_inode_block,
+ uncompressed_file, uncompressed_directory, file_count, sym_count, dev_count, dir_count, fifo_count, sock_count)) == 0) {
+ ERROR("read_filesystem: inode table read failed\n");
+ goto error;
+ }
+
+ *uncompressed_inode = root_inode_block;
+
+ printf("Read existing filesystem, %d inodes scanned\n", files);
+
+ if(inode.inode_type == SQUASHFS_DIR_TYPE) {
+ if((directory_table = squashfs_readdir(fd, !root_name, sBlk->directory_table_start + inode.start_block,
+ inode.offset, inode.file_size, sBlk, push_directory_entry)) == NULL) {
+ ERROR("read_filesystem: Could not read root directory\n");
+ goto error;
+ }
+
+ if((*cinode_table = (char *) malloc(root_inode_start - start)) == NULL) {
+ ERROR("read_filesystem: failed to alloc space for existing filesystem inode table\n");
+ goto error;
+ }
+
+ read_bytes(fd, start, root_inode_start - start, *cinode_table);
+
+ if((*cdirectory_table = (char *) malloc(inode.start_block)) == NULL) {
+ ERROR("read_filesystem: failed to alloc space for existing filesystem inode table\n");
+ goto error;
+ }
+
+ read_bytes(fd, sBlk->directory_table_start, inode.start_block, *cdirectory_table);
+
+ *inode_bytes = root_inode_start - start;
+ *directory_bytes = inode.start_block;
+
+ root_inode_offset += sizeof(inode);
+ root_directory_offset = inode.offset + inode.file_size;
+ (*dir_count) ++;
+
+ if(((*data_cache = (char *) malloc(root_inode_offset)) == NULL) ||
+ ((*directory_data_cache = (char *) malloc(root_directory_offset)) == NULL)) {
+ ERROR("read_filesystem: failed to alloc inode/directory caches\n");
+ goto error;
+ }
+
+ memcpy(*data_cache, inode_table + root_inode_block, root_inode_offset);
+ memcpy(*directory_data_cache, directory_table, root_directory_offset);
+ *cache_size = root_inode_offset;
+ *directory_cache_size = root_directory_offset;
+
+ if(root_name) {
+ push_directory_entry(root_name, sBlk->root_inode, SQUASHFS_DIR_TYPE);
+ *cache_bytes = root_inode_offset;
+ *directory_cache_bytes = root_directory_offset;
+ } else {
+ *cache_bytes = root_inode_offset - sizeof(inode);
+ *directory_cache_bytes = inode.offset;
+ }
+
+ if(!swap)
+ read_bytes(fd, sBlk->uid_start, sBlk->no_uids * sizeof(squashfs_uid), (char *) uids);
+ else {
+ squashfs_uid uids_copy[sBlk->no_uids];
+
+ read_bytes(fd, sBlk->uid_start, sBlk->no_uids * sizeof(squashfs_uid), (char *) uids_copy);
+ SQUASHFS_SWAP_DATA(uids, uids_copy, sBlk->no_uids, sizeof(squashfs_uid) * 8);
+ }
+
+ if(!swap)
+ read_bytes(fd, sBlk->guid_start, sBlk->no_guids * sizeof(squashfs_uid), (char *) guids);
+ else {
+ squashfs_uid guids_copy[sBlk->no_guids];
+
+ read_bytes(fd, sBlk->guid_start, sBlk->no_guids * sizeof(squashfs_uid), (char *) guids_copy);
+ SQUASHFS_SWAP_DATA(guids, guids_copy, sBlk->no_guids, sizeof(squashfs_uid) * 8);
+ }
+ *uid_count = sBlk->no_uids;
+ *guid_count = sBlk->no_guids;
+
+ free(inode_table);
+ free(directory_table);
+ return sBlk->inode_table_start;
+ }
+
+error:
+ return 0;
+}