/* * Unsquash a squashfs filesystem. This is a highly compressed read only filesystem. * * Copyright (c) 2002, 2003, 2004, 2005, 2006 * Phillip Lougher * * 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. * * unsquash.c */ #define TRUE 1 #define FALSE 0 #include #include #include #include #include #include #include #include #include #include #ifndef linux #define __BYTE_ORDER BYTE_ORDER #define __BIG_ENDIAN BIG_ENDIAN #define __LITTLE_ENDIAN LITTLE_ENDIAN #else #include #endif #include #include "read_fs.h" #include "global.h" #include #ifdef SQUASHFS_TRACE #define TRACE(s, args...) do { \ printf("mksquashfs: "s, ## args); \ } while(0) #else #define TRACE(s, args...) #endif #define ERROR(s, args...) do { \ fprintf(stderr, s, ## args); \ } while(0) #define EXIT_UNSQUASH(s, args...) do { \ fprintf(stderr, "FATAL ERROR aborting: "s, ## args); \ } while(0) struct hash_table_entry { int start; int bytes; struct hash_table_entry *next; }; int bytes = 0, swap, file_count = 0, dir_count = 0, sym_count = 0, dev_count = 0, fifo_count = 0; char *inode_table = NULL, *directory_table = NULL; struct hash_table_entry *inode_table_hash[65536], *directory_table_hash[65536]; int fd; squashfs_fragment_entry *fragment_table; unsigned int *uid_table, *guid_table; unsigned int cached_frag = SQUASHFS_INVALID_FRAG; char *fragment_data; char *file_data; char *data; unsigned int block_size; int lsonly = FALSE, info = FALSE; char **created_inode; #define CALCULATE_HASH(start) (start & 0xffff) int add_entry(struct hash_table_entry *hash_table[], int start, int bytes) { int hash = CALCULATE_HASH(start); struct hash_table_entry *hash_table_entry; if((hash_table_entry = malloc(sizeof(struct hash_table_entry))) == NULL) { ERROR("add_hash: out of memory in malloc\n"); return FALSE; } hash_table_entry->start = start; hash_table_entry->bytes = bytes; hash_table_entry->next = hash_table[hash]; hash_table[hash] = hash_table_entry; return TRUE; } int lookup_entry(struct hash_table_entry *hash_table[], int start) { int hash = CALCULATE_HASH(start); struct hash_table_entry *hash_table_entry; for(hash_table_entry = hash_table[hash]; hash_table_entry; hash_table_entry = hash_table_entry->next) if(hash_table_entry->start == start) return hash_table_entry->bytes; return -1; } int read_bytes(long long byte, int bytes, char *buff) { off_t off = byte; TRACE("read_bytes: reading from position 0x%llx, bytes %d\n", byte, bytes); if(lseek(fd, off, SEEK_SET) == -1) { ERROR("Lseek failed because %s\b", strerror(errno)); return FALSE; } if(read(fd, buff, bytes) == -1) { ERROR("Read on destination failed because %s\n", strerror(errno)); return FALSE; } return TRUE; } int read_block(long long start, long long *next, char *block, squashfs_super_block *sBlk) { unsigned short c_byte; int offset = 2; if(swap) { if(read_bytes(start, 2, block) == FALSE) goto failed; ((unsigned char *) &c_byte)[1] = block[0]; ((unsigned char *) &c_byte)[0] = block[1]; } else if(read_bytes(start, 2, (char *)&c_byte) == FALSE) goto failed; TRACE("read_block: block @0x%llx, %d %s bytes\n", start, SQUASHFS_COMPRESSED_SIZE(c_byte), SQUASHFS_COMPRESSED(c_byte) ? "compressed" : "uncompressed"); if(SQUASHFS_CHECK_DATA(sBlk->flags)) offset = 3; if(SQUASHFS_COMPRESSED(c_byte)) { char buffer[SQUASHFS_METADATA_SIZE]; int res; unsigned long bytes = SQUASHFS_METADATA_SIZE; c_byte = SQUASHFS_COMPRESSED_SIZE(c_byte); if(read_bytes(start + offset, c_byte, buffer) == FALSE) goto failed; if((res = uncompress((unsigned char *) block, &bytes, (const unsigned 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); goto failed; } if(next) *next = start + offset + c_byte; return bytes; } else { c_byte = SQUASHFS_COMPRESSED_SIZE(c_byte); if(read_bytes(start + offset, c_byte, block) == FALSE) goto failed; if(next) *next = start + offset + c_byte; return c_byte; } failed: return FALSE; } int read_data_block(long long start, unsigned int size, char *block) { int res; unsigned long bytes = block_size; int c_byte = SQUASHFS_COMPRESSED_SIZE_BLOCK(size); TRACE("read_data_block: block @0x%llx, %d %s bytes\n", start, SQUASHFS_COMPRESSED_SIZE_BLOCK(c_byte), SQUASHFS_COMPRESSED_BLOCK(c_byte) ? "compressed" : "uncompressed"); if(SQUASHFS_COMPRESSED_BLOCK(size)) { if(read_bytes(start, c_byte, data) == FALSE) return 0; if((res = uncompress((unsigned char *) block, &bytes, (const unsigned char *) data, 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; } return bytes; } else { if(read_bytes(start, c_byte, block) == FALSE) return 0; return c_byte; } } void uncompress_inode_table(long long start, long long end, squashfs_super_block *sBlk) { int size = 0, bytes = 0, res; while(start < end) { if((size - bytes < SQUASHFS_METADATA_SIZE) && ((inode_table = realloc(inode_table, size += SQUASHFS_METADATA_SIZE)) == NULL)) EXIT_UNSQUASH("uncompress_inode_table: out of memory in realloc\n"); TRACE("uncompress_inode_table: reading block 0x%llx\n", start); add_entry(inode_table_hash, start, bytes); if((res = read_block(start, &start, inode_table + bytes, sBlk)) == 0) { free(inode_table); EXIT_UNSQUASH("uncompress_inode_table: failed to read block\n"); } bytes += res; } } int set_attributes(char *pathname, unsigned int mode, unsigned int uid, unsigned int guid, unsigned int mtime, unsigned int set_mode) { struct utimbuf times = { (time_t) mtime, (time_t) mtime }; if(utime(pathname, ×) == -1) { ERROR("set_attributes: failed to set time on %s, because %s\n", pathname, strerror(errno)); return FALSE; } if(set_mode && chmod(pathname, (mode_t) mode) == -1) { ERROR("set_attributes: failed to change mode %s, because %s\n", pathname, strerror(errno)); return FALSE; } if(geteuid() == 0) { uid_t uid_value = (uid_t) uid_table[uid]; uid_t guid_value = guid == SQUASHFS_GUIDS ? uid_value : (uid_t) guid_table[guid]; if(chown(pathname, uid_value, guid_value) == -1) { ERROR("set_attributes: failed to change uid and gids on %s, because %s\n", pathname, strerror(errno)); return FALSE; } } return TRUE; } void read_uids_guids(squashfs_super_block *sBlk) { if((uid_table = malloc((sBlk->no_uids + sBlk->no_guids) * sizeof(unsigned int))) == NULL) EXIT_UNSQUASH("read_uids_guids: failed to allocate uid/gid table\n"); guid_table = uid_table + sBlk->no_uids; if(read_bytes(sBlk->uid_start, (sBlk->no_uids + sBlk->no_guids) * sizeof(unsigned int), (char *) uid_table) == FALSE) EXIT_UNSQUASH("read_uids_guids: failed to read uid/gid table\n"); } void read_fragment_table(squashfs_super_block *sBlk) { 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%llx\n", sBlk->fragments, indexes, sBlk->fragment_table_start); if(sBlk->fragments == 0) return; if((fragment_table = (squashfs_fragment_entry *) malloc(sBlk->fragments * sizeof(squashfs_fragment_entry))) == NULL) EXIT_UNSQUASH("read_fragment_table: failed to allocate fragment table\n"); if(swap) { squashfs_fragment_index sfragment_table_index[indexes]; read_bytes(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(sBlk->fragment_table_start, SQUASHFS_FRAGMENT_INDEX_BYTES(sBlk->fragments), (char *) fragment_table_index); for(i = 0; i < indexes; i++) { int length = read_block(fragment_table_index[i], NULL, ((char *) fragment_table) + (i * SQUASHFS_METADATA_SIZE), sBlk); TRACE("Read fragment table block %d, from 0x%llx, 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)); } } } char *read_fragment(unsigned int fragment) { TRACE("read_fragment: reading fragment %d\n", fragment); if(cached_frag == SQUASHFS_INVALID_FRAG || fragment != cached_frag) { squashfs_fragment_entry *fragment_entry = &fragment_table[fragment]; if(read_data_block(fragment_entry->start_block, fragment_entry->size, fragment_data) == 0) { ERROR("read_fragment: failed to read fragment %d\n", fragment); cached_frag = SQUASHFS_INVALID_FRAG; return NULL; } cached_frag = fragment; } return fragment_data; } int write_file(char *pathname, unsigned int fragment, unsigned int frag_bytes, unsigned int offset, unsigned int blocks, long long start, char *block_ptr, unsigned int mode) { unsigned int file_fd, bytes, i; unsigned int *block_list; TRACE("write_file: regular file, blocks %d\n", blocks); if((block_list = malloc(blocks * sizeof(unsigned int))) == NULL) { ERROR("write_file: unable to malloc block list\n"); return FALSE; } if(swap) { unsigned int sblock_list[blocks]; memcpy(sblock_list, block_ptr, blocks * sizeof(unsigned int)); SQUASHFS_SWAP_INTS(block_list, sblock_list, blocks); } else memcpy(block_list, block_ptr, blocks * sizeof(unsigned int)); if((file_fd = open(pathname, O_CREAT | O_WRONLY, (mode_t) mode)) == -1) { ERROR("write_file: failed to create file %s, because %s\n", pathname, strerror(errno)); free(block_list); return FALSE; } for(i = 0; i < blocks; i++) { if((bytes = read_data_block(start, block_list[i], file_data)) == 0) { ERROR("write_file: failed to read data block 0x%llx\n", start); goto failure; } if(write(file_fd, file_data, bytes) < bytes) { ERROR("write_file: failed to write data block 0x%llx\n", start); goto failure; } start += SQUASHFS_COMPRESSED_SIZE_BLOCK(block_list[i]); } if(frag_bytes != 0) { char *fragment_data = read_fragment(fragment); if(fragment_data == NULL) goto failure; if(write(file_fd, fragment_data + offset, frag_bytes) < frag_bytes) { ERROR("write_file: failed to write fragment %d\n", fragment); goto failure; } } close(file_fd); return TRUE; failure: close(file_fd); free(block_list); return FALSE; } int create_inode(char *pathname, unsigned int start_block, unsigned int offset, squashfs_super_block *sBlk) { long long start = sBlk->inode_table_start + start_block; squashfs_inode_header header; char *block_ptr; int bytes = lookup_entry(inode_table_hash, start), file_fd; TRACE("create_inode: pathname %s, start 0x%llx, offset %d\n", pathname, start, offset); if(bytes == -1) { ERROR("create_inode: inode block 0x%llx out of range!\n", start); return FALSE; } block_ptr = inode_table + bytes + offset; if(swap) { squashfs_base_inode_header sinode; memcpy(&sinode, block_ptr, sizeof(header.base)); SQUASHFS_SWAP_BASE_INODE_HEADER(&header.base, &sinode, sizeof(squashfs_base_inode_header)); } else memcpy(&header.base, block_ptr, sizeof(header.base)); if(created_inode[header.base.inode_number - 1]) { TRACE("create_inode: hard link\n"); if(link(created_inode[header.base.inode_number - 1], pathname) == -1) { ERROR("create_inode: failed to create hardlink, because %s\n", strerror(errno)); return FALSE; } return TRUE; } switch(header.base.inode_type) { case SQUASHFS_FILE_TYPE: { unsigned int frag_bytes; unsigned int blocks; unsigned int offset; long long start; squashfs_reg_inode_header *inode = &header.reg; if(swap) { squashfs_reg_inode_header sinode; memcpy(&sinode, block_ptr, sizeof(sinode)); SQUASHFS_SWAP_REG_INODE_HEADER(inode, &sinode); } else memcpy(inode, block_ptr, sizeof(*inode)); frag_bytes = inode->fragment == SQUASHFS_INVALID_FRAG ? 0 : inode->file_size % sBlk->block_size; offset = inode->offset; blocks = inode->fragment == SQUASHFS_INVALID_FRAG ? (inode->file_size + sBlk->block_size - 1) >> sBlk->block_log : inode->file_size >> sBlk->block_log; start = inode->start_block; TRACE("create_inode: regular file, file_size %lld, blocks %d\n", inode->file_size, blocks); if(write_file(pathname, inode->fragment, frag_bytes, offset, blocks, start, block_ptr + sizeof(*inode), inode->mode)) { set_attributes(pathname, inode->mode, inode->uid, inode->guid, inode->mtime, FALSE); file_count ++; } break; } case SQUASHFS_LREG_TYPE: { unsigned int frag_bytes; unsigned int blocks; unsigned int offset; long long start; squashfs_lreg_inode_header *inode = &header.lreg; if(swap) { squashfs_lreg_inode_header sinode; memcpy(&sinode, block_ptr, sizeof(sinode)); SQUASHFS_SWAP_LREG_INODE_HEADER(inode, &sinode); } else memcpy(inode, block_ptr, sizeof(*inode)); frag_bytes = inode->fragment == SQUASHFS_INVALID_FRAG ? 0 : inode->file_size % sBlk->block_size; offset = inode->offset; blocks = inode->fragment == SQUASHFS_INVALID_FRAG ? (inode->file_size + sBlk->block_size - 1) >> sBlk->block_log : inode->file_size >> sBlk->block_log; start = inode->start_block; TRACE("create_inode: regular file, file_size %lld, blocks %d\n", inode->file_size, blocks); if(write_file(pathname, inode->fragment, frag_bytes, offset, blocks, start, block_ptr + sizeof(*inode), inode->mode)) { set_attributes(pathname, inode->mode, inode->uid, inode->guid, inode->mtime, FALSE); file_count ++; } break; } case SQUASHFS_SYMLINK_TYPE: { squashfs_symlink_inode_header *inodep = &header.symlink; char name[65536]; if(swap) { squashfs_symlink_inode_header sinodep; memcpy(&sinodep, block_ptr, sizeof(sinodep)); SQUASHFS_SWAP_SYMLINK_INODE_HEADER(inodep, &sinodep); } else memcpy(inodep, block_ptr, sizeof(*inodep)); TRACE("create_inode: symlink, symlink_size %d\n", inodep->symlink_size); strncpy(name, block_ptr + sizeof(squashfs_symlink_inode_header), inodep->symlink_size); name[inodep->symlink_size] = '\0'; if(symlink(name, pathname) == -1) { ERROR("create_inode: failed to create symlink %s, because %s\n", pathname, strerror(errno)); break; } if(geteuid() == 0) { uid_t uid_value = (uid_t) uid_table[inodep->uid]; uid_t guid_value = inodep->guid == SQUASHFS_GUIDS ? uid_value : (uid_t) guid_table[inodep->guid]; if(lchown(pathname, uid_value, guid_value) == -1) ERROR("create_inode: failed to change uid and gids on %s, because %s\n", pathname, strerror(errno)); } sym_count ++; break; } case SQUASHFS_BLKDEV_TYPE: case SQUASHFS_CHRDEV_TYPE: { squashfs_dev_inode_header *inodep = &header.dev; if(swap) { squashfs_dev_inode_header sinodep; memcpy(&sinodep, block_ptr, sizeof(sinodep)); SQUASHFS_SWAP_DEV_INODE_HEADER(inodep, &sinodep); } else memcpy(inodep, block_ptr, sizeof(*inodep)); TRACE("create_inode: dev, rdev 0x%x\n", inodep->rdev); if(geteuid() == 0) { if(mknod(pathname, inodep->inode_type == SQUASHFS_CHRDEV_TYPE ? S_IFCHR : S_IFBLK, makedev((inodep->rdev >> 8) & 0xff, inodep->rdev & 0xff)) == -1) { ERROR("create_inode: failed to create %s device %s, because %s\n", inodep->inode_type == SQUASHFS_CHRDEV_TYPE ? "character" : "block", pathname, strerror(errno)); break; } set_attributes(pathname, inodep->mode, inodep->uid, inodep->guid, inodep->mtime, TRUE); dev_count ++; } else ERROR("create_inode: could not create %s device %s, because you're not superuser!\n", inodep->inode_type == SQUASHFS_CHRDEV_TYPE ? "character" : "block", pathname, strerror(errno)); break; } case SQUASHFS_FIFO_TYPE: TRACE("create_inode: fifo\n"); if(mknod(pathname, S_IFIFO, 0) == -1) { ERROR("create_inode: failed to create fifo %s, because %s\n", pathname, strerror(errno)); break; } set_attributes(pathname, header.base.mode, header.base.uid, header.base.guid, header.base.mtime, TRUE); fifo_count ++; break; case SQUASHFS_SOCKET_TYPE: TRACE("create_inode: socket\n"); ERROR("create_inode: socket %s ignored\n", pathname); break; default: ERROR("Unknown inode type %d in create_inode_table!\n", header.base.inode_type); return FALSE; } created_inode[header.base.inode_number - 1] = strdup(pathname); return TRUE; } void uncompress_directory_table(long long start, long long end, squashfs_super_block *sBlk) { int bytes = 0, size = 0, res; while(start < end) { if(size - bytes < SQUASHFS_METADATA_SIZE && (directory_table = realloc(directory_table, size += SQUASHFS_METADATA_SIZE)) == NULL) EXIT_UNSQUASH("uncompress_directory_table: out of memory in realloc\n"); TRACE("uncompress_directory_table: reading block 0x%llx\n", start); add_entry(directory_table_hash, start, bytes); if((res = read_block(start, &start, directory_table + bytes, sBlk)) == 0) EXIT_UNSQUASH("uncompress_directory_table: failed to read block\n"); bytes += res; } } #define DIR_ENT_SIZE 16 struct dir_ent { char name[SQUASHFS_NAME_LEN + 1]; unsigned int start_block; unsigned int offset; unsigned int type; }; struct dir { int dir_count; int cur_entry; unsigned int mode; unsigned int uid; unsigned int guid; unsigned int mtime; struct dir_ent *dirs; }; struct dir *squashfs_openddir(unsigned int block_start, unsigned int offset, squashfs_super_block *sBlk) { squashfs_dir_header dirh; char buffer[sizeof(squashfs_dir_entry) + SQUASHFS_NAME_LEN + 1]; squashfs_dir_entry *dire = (squashfs_dir_entry *) buffer; long long start = sBlk->inode_table_start + block_start; char *block_ptr; int bytes = lookup_entry(inode_table_hash, start); squashfs_inode_header header; int dir_count, size; struct dir_ent *new_dir; struct dir *dir; TRACE("squashfs_opendir: inode start block %d, offset %d\n", block_start, offset); if(bytes == -1) { ERROR("squashfs_opendir: inode block %d not found!\n", block_start); return NULL; } block_ptr = inode_table + bytes + offset; if(swap) { squashfs_dir_inode_header sinode; memcpy(&sinode, block_ptr, sizeof(header.dir)); SQUASHFS_SWAP_DIR_INODE_HEADER(&header.dir, &sinode); } else memcpy(&header.dir, block_ptr, sizeof(header.dir)); switch(header.dir.inode_type) { case SQUASHFS_DIR_TYPE: block_start = header.dir.start_block; offset = header.dir.offset; size = header.dir.file_size; break; case SQUASHFS_LDIR_TYPE: if(swap) { squashfs_ldir_inode_header sinode; memcpy(&sinode, block_ptr, sizeof(header.ldir)); SQUASHFS_SWAP_LDIR_INODE_HEADER(&header.ldir, &sinode); } else memcpy(&header.ldir, block_ptr, sizeof(header.ldir)); block_start = header.ldir.start_block; offset = header.ldir.offset; size = header.ldir.file_size; break; default: ERROR("squashfs_opendir: inode not a directory\n"); return NULL; } start = sBlk->directory_table_start + block_start; bytes = lookup_entry(directory_table_hash, start); if(bytes == -1) { ERROR("squashfs_opendir: directory block %d not found!\n", block_start); return NULL; } bytes += offset; size += bytes - 3; if((dir = malloc(sizeof(struct dir))) == NULL) { ERROR("squashfs_opendir: malloc failed!\n"); return NULL; } dir->dir_count = 0; dir->cur_entry = 0; dir->mode = header.dir.mode; dir->uid = header.dir.uid; dir->guid = header.dir.guid; dir->mtime = header.dir.mtime; dir->dirs = NULL; while(bytes < size) { if(swap) { squashfs_dir_header sdirh; memcpy(&sdirh, directory_table + bytes, sizeof(sdirh)); SQUASHFS_SWAP_DIR_HEADER(&dirh, &sdirh); } else memcpy(&dirh, directory_table + bytes, sizeof(dirh)); dir_count = dirh.count + 1; TRACE("squashfs_opendir: Read directory header @ byte position %d, %d directory entries\n", bytes, dir_count); bytes += sizeof(dirh); while(dir_count--) { if(swap) { squashfs_dir_entry sdire; memcpy(&sdire, directory_table + bytes, sizeof(sdire)); SQUASHFS_SWAP_DIR_ENTRY(dire, &sdire); } else memcpy(dire, directory_table + bytes, sizeof(dire)); bytes += sizeof(*dire); memcpy(dire->name, directory_table + bytes, dire->size + 1); dire->name[dire->size + 1] = '\0'; TRACE("squashfs_opendir: directory entry %s, inode %d:%d, type %d\n", dire->name, dirh.start_block, dire->offset, dire->type); if((dir->dir_count % DIR_ENT_SIZE) == 0) { if((new_dir = realloc(dir->dirs, (dir->dir_count + DIR_ENT_SIZE) * sizeof(struct dir_ent))) == NULL) { ERROR("squashfs_opendir: realloc failed!\n"); free(dir->dirs); free(dir); return NULL; } dir->dirs = new_dir; } strcpy(dir->dirs[dir->dir_count].name, dire->name); dir->dirs[dir->dir_count].start_block = dirh.start_block; dir->dirs[dir->dir_count].offset = dire->offset; dir->dirs[dir->dir_count].type = dire->type; dir->dir_count ++; bytes += dire->size + 1; } } return dir; } int squashfs_readdir(struct dir *dir, char **name, unsigned int *start_block, unsigned int *offset, unsigned int *type) { if(dir->cur_entry == dir->dir_count) return FALSE; *name = dir->dirs[dir->cur_entry].name; *start_block = dir->dirs[dir->cur_entry].start_block; *offset = dir->dirs[dir->cur_entry].offset; *type = dir->dirs[dir->cur_entry].type; dir->cur_entry ++; return TRUE; } void squashfs_closedir(struct dir *dir) { free(dir->dirs); free(dir); } int dir_scan(char *parent_name, unsigned int start_block, unsigned int offset, squashfs_super_block *sBlk) { struct dir *dir = squashfs_openddir(start_block, offset, sBlk); unsigned int type; char *name, pathname[1024]; if(dir == NULL) { ERROR("dir_scan: Failed to read directory %s (%x:%x)\n", parent_name, start_block, offset); return FALSE; } if(!lsonly && mkdir(parent_name, (mode_t) dir->mode) == -1) { ERROR("dir_scan: failed to open directory %s, because %s\n", parent_name, strerror(errno)); return FALSE; } while(squashfs_readdir(dir, &name, &start_block, &offset, &type)) { TRACE("dir_scan: name %s, start_block %d, offset %d, type %d\n", name, start_block, offset, type); strcat(strcat(strcpy(pathname, parent_name), "/"), name); if(lsonly || info) printf("%s\n", pathname); if(type == SQUASHFS_DIR_TYPE) dir_scan(pathname, start_block, offset, sBlk); else if(!lsonly) create_inode(pathname, start_block, offset, sBlk); } !lsonly && set_attributes(parent_name, dir->mode, dir->uid, dir->guid, dir->mtime, TRUE); squashfs_closedir(dir); dir_count ++; return TRUE; } int read_super(squashfs_super_block *sBlk, char *source) { read_bytes(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\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) { ERROR("Major/Minor mismatch, filesystem on %s is (%d:%d)\n", source, sBlk->s_major, sBlk->s_minor); ERROR("I only support Squashfs 3.0 filesystems! Later releases will support older Squashfs filesystems\n"); goto failed_mount; } #if __BYTE_ORDER == __BIG_ENDIAN TRACE("Found a valid %s endian SQUASHFS superblock on %s.\n", swap ? "little" : "big", source); #else TRACE("Found a valid %s endian SQUASHFS superblock on %s.\n", swap ? "big" : "little", source); #endif TRACE("\tInodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(sBlk->flags) ? "un" : ""); TRACE("\tData is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(sBlk->flags) ? "un" : ""); TRACE("\tFragments are %scompressed\n", SQUASHFS_UNCOMPRESSED_FRAGMENTS(sBlk->flags) ? "un" : ""); TRACE("\tCheck data is %s present in the filesystem\n", SQUASHFS_CHECK_DATA(sBlk->flags) ? "" : "not"); TRACE("\tFragments are %s present in the filesystem\n", SQUASHFS_NO_FRAGMENTS(sBlk->flags) ? "not" : ""); TRACE("\tAlways_use_fragments option is %s specified\n", SQUASHFS_ALWAYS_FRAGMENTS(sBlk->flags) ? "" : "not"); TRACE("\tDuplicates are %s removed\n", SQUASHFS_DUPLICATES(sBlk->flags) ? "" : "not"); TRACE("\tFilesystem size %.2f Kbytes (%.2f Mbytes)\n", sBlk->bytes_used / 1024.0, sBlk->bytes_used / (1024.0 * 1024.0)); TRACE("\tBlock size %d\n", sBlk->block_size); TRACE("\tNumber of fragments %d\n", sBlk->fragments); TRACE("\tNumber of inodes %d\n", sBlk->inodes); TRACE("\tNumber of uids %d\n", sBlk->no_uids); TRACE("\tNumber of gids %d\n", sBlk->no_guids); TRACE("sBlk->inode_table_start 0x%llx\n", sBlk->inode_table_start); TRACE("sBlk->directory_table_start 0x%llx\n", sBlk->directory_table_start); TRACE("sBlk->uid_start 0x%llx\n", sBlk->uid_start); TRACE("sBlk->fragment_table_start 0x%llx\n", sBlk->fragment_table_start); TRACE("\n"); return TRUE; failed_mount: return FALSE; } #define VERSION() \ printf("unsquashfs version 1.0 (2006/03/15)\n");\ printf("copyright (C) 2006 Phillip Lougher \n\n"); \ printf("This program is free software; you can redistribute it and/or\n");\ printf("modify it under the terms of the GNU General Public License\n");\ printf("as published by the Free Software Foundation; either version 2,\n");\ printf("or (at your option) any later version.\n\n");\ printf("This program is distributed in the hope that it will be useful,\n");\ printf("but WITHOUT ANY WARRANTY; without even the implied warranty of\n");\ printf("MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\n");\ printf("GNU General Public License for more details.\n"); int main(int argc, char *argv[]) { squashfs_super_block sBlk; char *dest = "squashfs-root"; int i, version = FALSE; for(i = 1; i < argc; i++) { if(*argv[i] != '-') break; if(strcmp(argv[i], "-version") == 0) { VERSION(); version = TRUE; } else if(strcmp(argv[i], "-info") == 0) info = TRUE; else if(strcmp(argv[i], "-ls") == 0) lsonly = TRUE; else if(strcmp(argv[i], "-dest") == 0) { if(++i == argc) goto options; dest = argv[i]; } } if(i == argc) { if(!version) { options: ERROR("SYNTAX: %s [-ls | -dest] filesystem\n", argv[0]); ERROR("\t-version\t\tprint version, licence and copyright information\n"); ERROR("\t-info\t\t\tprint files as they are unsquashed\n"); ERROR("\t-ls\t\t\tlist filesystem only\n"); ERROR("\t-dest \tunsquash to , default \"squashfs-root\"\n"); } exit(1); } if((fd = open(argv[i], O_RDONLY)) == -1) { ERROR("Could not open %s, because %s\n", argv[i], strerror(errno)); exit(1); } if(read_super(&sBlk, argv[i]) == FALSE) exit(1); block_size = sBlk.block_size; if((fragment_data = malloc(block_size)) == NULL) EXIT_UNSQUASH("failed to allocate fragment_data\n"); if((file_data = malloc(block_size)) == NULL) EXIT_UNSQUASH("failed to allocate file_data"); if((data = malloc(block_size)) == NULL) EXIT_UNSQUASH("failed to allocate datan\n"); if((created_inode = malloc(sBlk.inodes * sizeof(char *))) == NULL) EXIT_UNSQUASH("failed to allocate created_inode\n"); memset(created_inode, 0, sBlk.inodes * sizeof(char *)); read_uids_guids(&sBlk); read_fragment_table(&sBlk); uncompress_inode_table(sBlk.inode_table_start, sBlk.directory_table_start, &sBlk); uncompress_directory_table(sBlk.directory_table_start, sBlk.fragment_table_start, &sBlk); dir_scan(dest, SQUASHFS_INODE_BLK(sBlk.root_inode), SQUASHFS_INODE_OFFSET(sBlk.root_inode), &sBlk); if(!lsonly) { printf("\n"); printf("created %d files\n", file_count); printf("created %d directories\n", dir_count); printf("created %d symlinks\n", sym_count); printf("created %d devices\n", dev_count); printf("created %d fifos\n", fifo_count); } }