| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2020 Bootlin |
| * |
| * Author: Joao Marcos Costa <joaomarcos.costa@bootlin.com> |
| * |
| * sqfs.c: SquashFS filesystem implementation |
| */ |
| |
| #include <asm/unaligned.h> |
| #include <errno.h> |
| #include <fs.h> |
| #include <linux/types.h> |
| #include <linux/byteorder/little_endian.h> |
| #include <linux/byteorder/generic.h> |
| #include <memalign.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <squashfs.h> |
| #include <part.h> |
| |
| #include "sqfs_decompressor.h" |
| #include "sqfs_filesystem.h" |
| #include "sqfs_utils.h" |
| |
| static struct squashfs_ctxt ctxt; |
| |
| static int sqfs_disk_read(__u32 block, __u32 nr_blocks, void *buf) |
| { |
| ulong ret; |
| |
| if (!ctxt.cur_dev) |
| return -1; |
| |
| ret = blk_dread(ctxt.cur_dev, ctxt.cur_part_info.start + block, |
| nr_blocks, buf); |
| |
| if (ret != nr_blocks) |
| return -1; |
| |
| return ret; |
| } |
| |
| static int sqfs_read_sblk(struct squashfs_super_block **sblk) |
| { |
| *sblk = malloc_cache_aligned(ctxt.cur_dev->blksz); |
| if (!*sblk) |
| return -ENOMEM; |
| |
| if (sqfs_disk_read(0, 1, *sblk) != 1) { |
| free(*sblk); |
| sblk = NULL; |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static int sqfs_count_tokens(const char *filename) |
| { |
| int token_count = 1, l; |
| |
| for (l = 1; l < strlen(filename); l++) { |
| if (filename[l] == '/') |
| token_count++; |
| } |
| |
| /* Ignore trailing '/' in path */ |
| if (filename[strlen(filename) - 1] == '/') |
| token_count--; |
| |
| if (!token_count) |
| token_count = 1; |
| |
| return token_count; |
| } |
| |
| /* |
| * Calculates how many blocks are needed for the buffer used in sqfs_disk_read. |
| * The memory section (e.g. inode table) start offset and its end (i.e. the next |
| * table start) must be specified. It also calculates the offset from which to |
| * start reading the buffer. |
| */ |
| static int sqfs_calc_n_blks(__le64 start, __le64 end, u64 *offset) |
| { |
| u64 start_, table_size; |
| |
| table_size = le64_to_cpu(end) - le64_to_cpu(start); |
| start_ = le64_to_cpu(start) / ctxt.cur_dev->blksz; |
| *offset = le64_to_cpu(start) - (start_ * ctxt.cur_dev->blksz); |
| |
| return DIV_ROUND_UP(table_size + *offset, ctxt.cur_dev->blksz); |
| } |
| |
| /* |
| * Retrieves fragment block entry and returns true if the fragment block is |
| * compressed |
| */ |
| static int sqfs_frag_lookup(u32 inode_fragment_index, |
| struct squashfs_fragment_block_entry *e) |
| { |
| u64 start, n_blks, src_len, table_offset, start_block; |
| unsigned char *metadata_buffer, *metadata, *table; |
| struct squashfs_fragment_block_entry *entries; |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| unsigned long dest_len; |
| int block, offset, ret; |
| u16 header; |
| |
| metadata_buffer = NULL; |
| entries = NULL; |
| table = NULL; |
| |
| if (inode_fragment_index >= get_unaligned_le32(&sblk->fragments)) |
| return -EINVAL; |
| |
| start = get_unaligned_le64(&sblk->fragment_table_start) / |
| ctxt.cur_dev->blksz; |
| n_blks = sqfs_calc_n_blks(sblk->fragment_table_start, |
| sblk->export_table_start, |
| &table_offset); |
| |
| /* Allocate a proper sized buffer to store the fragment index table */ |
| table = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz); |
| if (!table) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (sqfs_disk_read(start, n_blks, table) < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| block = SQFS_FRAGMENT_INDEX(inode_fragment_index); |
| offset = SQFS_FRAGMENT_INDEX_OFFSET(inode_fragment_index); |
| |
| /* |
| * Get the start offset of the metadata block that contains the right |
| * fragment block entry |
| */ |
| start_block = get_unaligned_le64(table + table_offset + block * |
| sizeof(u64)); |
| |
| start = start_block / ctxt.cur_dev->blksz; |
| n_blks = sqfs_calc_n_blks(cpu_to_le64(start_block), |
| sblk->fragment_table_start, &table_offset); |
| |
| metadata_buffer = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz); |
| if (!metadata_buffer) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (sqfs_disk_read(start, n_blks, metadata_buffer) < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Every metadata block starts with a 16-bit header */ |
| header = get_unaligned_le16(metadata_buffer + table_offset); |
| metadata = metadata_buffer + table_offset + SQFS_HEADER_SIZE; |
| |
| if (!metadata || !header) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| entries = malloc(SQFS_METADATA_BLOCK_SIZE); |
| if (!entries) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (SQFS_COMPRESSED_METADATA(header)) { |
| src_len = SQFS_METADATA_SIZE(header); |
| dest_len = SQFS_METADATA_BLOCK_SIZE; |
| ret = sqfs_decompress(&ctxt, entries, &dest_len, metadata, |
| src_len); |
| if (ret) { |
| ret = -EINVAL; |
| goto out; |
| } |
| } else { |
| memcpy(entries, metadata, SQFS_METADATA_SIZE(header)); |
| } |
| |
| *e = entries[offset]; |
| ret = SQFS_COMPRESSED_BLOCK(e->size); |
| |
| out: |
| free(entries); |
| free(metadata_buffer); |
| free(table); |
| |
| return ret; |
| } |
| |
| /* |
| * The entry name is a flexible array member, and we don't know its size before |
| * actually reading the entry. So we need a first copy to retrieve this size so |
| * we can finally copy the whole struct. |
| */ |
| static int sqfs_read_entry(struct squashfs_directory_entry **dest, void *src) |
| { |
| struct squashfs_directory_entry *tmp; |
| u16 sz; |
| |
| tmp = src; |
| sz = get_unaligned_le16(src + sizeof(*tmp) - sizeof(u16)); |
| /* |
| * 'src' points to the begin of a directory entry, and 'sz' gets its |
| * 'name_size' member's value. name_size is actually the string |
| * length - 1, so adding 2 compensates this difference and adds space |
| * for the trailling null byte. |
| */ |
| *dest = malloc(sizeof(*tmp) + sz + 2); |
| if (!*dest) |
| return -ENOMEM; |
| |
| memcpy(*dest, src, sizeof(*tmp) + sz + 1); |
| (*dest)->name[sz + 1] = '\0'; |
| |
| return 0; |
| } |
| |
| static int sqfs_get_tokens_length(char **tokens, int count) |
| { |
| int length = 0, i; |
| |
| /* |
| * 1 is added to the result of strlen to consider the slash separator |
| * between the tokens. |
| */ |
| for (i = 0; i < count; i++) |
| length += strlen(tokens[i]) + 1; |
| |
| return length; |
| } |
| |
| /* Takes a token list and returns a single string with '/' as separator. */ |
| static char *sqfs_concat_tokens(char **token_list, int token_count) |
| { |
| char *result; |
| int i, length = 0, offset = 0; |
| |
| length = sqfs_get_tokens_length(token_list, token_count); |
| |
| result = malloc(length + 1); |
| if (!result) |
| return NULL; |
| |
| result[length] = '\0'; |
| |
| for (i = 0; i < token_count; i++) { |
| strcpy(result + offset, token_list[i]); |
| offset += strlen(token_list[i]); |
| result[offset++] = '/'; |
| } |
| |
| return result; |
| } |
| |
| /* |
| * Differently from sqfs_concat_tokens, sqfs_join writes the result into a |
| * previously allocated string, and returns the number of bytes written. |
| */ |
| static int sqfs_join(char **strings, char *dest, int start, int end, |
| char separator) |
| { |
| int i, offset = 0; |
| |
| for (i = start; i < end; i++) { |
| strcpy(dest + offset, strings[i]); |
| offset += strlen(strings[i]); |
| if (i < end - 1) |
| dest[offset++] = separator; |
| } |
| |
| return offset; |
| } |
| |
| /* |
| * Fills the given token list using its size (count) and a source string (str) |
| */ |
| static int sqfs_tokenize(char **tokens, int count, const char *str) |
| { |
| int i, j, ret = 0; |
| char *aux, *strc; |
| |
| strc = strdup(str); |
| if (!strc) |
| return -ENOMEM; |
| |
| if (!strcmp(strc, "/")) { |
| tokens[0] = strdup(strc); |
| if (!tokens[0]) { |
| ret = -ENOMEM; |
| goto free_strc; |
| } |
| } else { |
| for (j = 0; j < count; j++) { |
| aux = strtok(!j ? strc : NULL, "/"); |
| tokens[j] = strdup(aux); |
| if (!tokens[j]) { |
| for (i = 0; i < j; i++) |
| free(tokens[i]); |
| ret = -ENOMEM; |
| goto free_strc; |
| } |
| } |
| } |
| |
| free_strc: |
| free(strc); |
| |
| return ret; |
| } |
| |
| /* |
| * Remove last 'updir + 1' tokens from the base path tokens list. This leaves us |
| * with a token list containing only the tokens needed to form the resolved |
| * path, and returns the decremented size of the token list. |
| */ |
| static int sqfs_clean_base_path(char **base, int count, int updir) |
| { |
| int i; |
| |
| for (i = count - updir - 1; i < count; i++) |
| free(base[i]); |
| |
| return count - updir - 1; |
| } |
| |
| /* |
| * Given the base ("current dir.") path and the relative one, generate the |
| * absolute path. |
| */ |
| static char *sqfs_get_abs_path(const char *base, const char *rel) |
| { |
| char **base_tokens, **rel_tokens, *resolved = NULL; |
| int ret, bc, rc, i, updir = 0, resolved_size = 0, offset = 0; |
| |
| base_tokens = NULL; |
| rel_tokens = NULL; |
| |
| /* Memory allocation for the token lists */ |
| bc = sqfs_count_tokens(base); |
| rc = sqfs_count_tokens(rel); |
| if (bc < 1 || rc < 1) |
| return NULL; |
| |
| base_tokens = calloc(bc, sizeof(char *)); |
| if (!base_tokens) |
| return NULL; |
| |
| rel_tokens = calloc(rc, sizeof(char *)); |
| if (!rel_tokens) |
| goto out; |
| |
| /* Fill token lists */ |
| ret = sqfs_tokenize(base_tokens, bc, base); |
| if (ret) |
| goto out; |
| |
| ret = sqfs_tokenize(rel_tokens, rc, rel); |
| if (ret) |
| goto out; |
| |
| /* count '..' occurrences in target path */ |
| for (i = 0; i < rc; i++) { |
| if (!strcmp(rel_tokens[i], "..")) |
| updir++; |
| } |
| |
| /* Remove the last token and the '..' occurrences */ |
| bc = sqfs_clean_base_path(base_tokens, bc, updir); |
| if (bc < 0) |
| goto out; |
| |
| /* Calculate resolved path size */ |
| if (!bc) |
| resolved_size++; |
| |
| resolved_size += sqfs_get_tokens_length(base_tokens, bc) + |
| sqfs_get_tokens_length(rel_tokens, rc); |
| |
| resolved = malloc(resolved_size + 1); |
| if (!resolved) |
| goto out; |
| |
| /* Set resolved path */ |
| memset(resolved, '\0', resolved_size + 1); |
| offset += sqfs_join(base_tokens, resolved + offset, 0, bc, '/'); |
| resolved[offset++] = '/'; |
| offset += sqfs_join(rel_tokens, resolved + offset, updir, rc, '/'); |
| |
| out: |
| if (rel_tokens) |
| for (i = 0; i < rc; i++) |
| free(rel_tokens[i]); |
| if (base_tokens) |
| for (i = 0; i < bc; i++) |
| free(base_tokens[i]); |
| |
| free(rel_tokens); |
| free(base_tokens); |
| |
| return resolved; |
| } |
| |
| static char *sqfs_resolve_symlink(struct squashfs_symlink_inode *sym, |
| const char *base_path) |
| { |
| char *resolved, *target; |
| u32 sz; |
| |
| sz = get_unaligned_le32(&sym->symlink_size); |
| target = malloc(sz + 1); |
| if (!target) |
| return NULL; |
| |
| /* |
| * There is no trailling null byte in the symlink's target path, so a |
| * copy is made and a '\0' is added at its end. |
| */ |
| target[sz] = '\0'; |
| /* Get target name (relative path) */ |
| strncpy(target, sym->symlink, sz); |
| |
| /* Relative -> absolute path conversion */ |
| resolved = sqfs_get_abs_path(base_path, target); |
| |
| free(target); |
| |
| return resolved; |
| } |
| |
| /* |
| * m_list contains each metadata block's position, and m_count is the number of |
| * elements of m_list. Those metadata blocks come from the compressed directory |
| * table. |
| */ |
| static int sqfs_search_dir(struct squashfs_dir_stream *dirs, char **token_list, |
| int token_count, u32 *m_list, int m_count) |
| { |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| char *path, *target, **sym_tokens, *res, *rem; |
| int j, ret = 0, new_inode_number, offset; |
| struct squashfs_symlink_inode *sym; |
| struct squashfs_ldir_inode *ldir; |
| struct squashfs_dir_inode *dir; |
| struct fs_dir_stream *dirsp; |
| struct fs_dirent *dent; |
| unsigned char *table; |
| |
| res = NULL; |
| rem = NULL; |
| path = NULL; |
| target = NULL; |
| sym_tokens = NULL; |
| |
| dirsp = (struct fs_dir_stream *)dirs; |
| |
| /* Start by root inode */ |
| table = sqfs_find_inode(dirs->inode_table, le32_to_cpu(sblk->inodes), |
| sblk->inodes, sblk->block_size); |
| |
| dir = (struct squashfs_dir_inode *)table; |
| ldir = (struct squashfs_ldir_inode *)table; |
| |
| /* get directory offset in directory table */ |
| offset = sqfs_dir_offset(table, m_list, m_count); |
| dirs->table = &dirs->dir_table[offset]; |
| |
| /* Setup directory header */ |
| dirs->dir_header = malloc(SQFS_DIR_HEADER_SIZE); |
| if (!dirs->dir_header) |
| return -ENOMEM; |
| |
| memcpy(dirs->dir_header, dirs->table, SQFS_DIR_HEADER_SIZE); |
| |
| /* Initialize squashfs_dir_stream members */ |
| dirs->table += SQFS_DIR_HEADER_SIZE; |
| dirs->size = get_unaligned_le16(&dir->file_size) - SQFS_DIR_HEADER_SIZE; |
| dirs->entry_count = dirs->dir_header->count + 1; |
| |
| /* No path given -> root directory */ |
| if (!strcmp(token_list[0], "/")) { |
| dirs->table = &dirs->dir_table[offset]; |
| memcpy(&dirs->i_dir, dir, sizeof(*dir)); |
| return 0; |
| } |
| |
| for (j = 0; j < token_count; j++) { |
| if (!sqfs_is_dir(get_unaligned_le16(&dir->inode_type))) { |
| printf("** Cannot find directory. **\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| while (!sqfs_readdir(dirsp, &dent)) { |
| ret = strcmp(dent->name, token_list[j]); |
| if (!ret) |
| break; |
| free(dirs->entry); |
| dirs->entry = NULL; |
| } |
| |
| if (ret) { |
| printf("** Cannot find directory. **\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Redefine inode as the found token */ |
| new_inode_number = dirs->entry->inode_offset + |
| dirs->dir_header->inode_number; |
| |
| /* Get reference to inode in the inode table */ |
| table = sqfs_find_inode(dirs->inode_table, new_inode_number, |
| sblk->inodes, sblk->block_size); |
| dir = (struct squashfs_dir_inode *)table; |
| |
| /* Check for symbolic link and inode type sanity */ |
| if (get_unaligned_le16(&dir->inode_type) == SQFS_SYMLINK_TYPE) { |
| sym = (struct squashfs_symlink_inode *)table; |
| /* Get first j + 1 tokens */ |
| path = sqfs_concat_tokens(token_list, j + 1); |
| if (!path) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| /* Resolve for these tokens */ |
| target = sqfs_resolve_symlink(sym, path); |
| if (!target) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| /* Join remaining tokens */ |
| rem = sqfs_concat_tokens(token_list + j + 1, token_count - |
| j - 1); |
| if (!rem) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| /* Concatenate remaining tokens and symlink's target */ |
| res = malloc(strlen(rem) + strlen(target) + 1); |
| if (!res) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| strcpy(res, target); |
| res[strlen(target)] = '/'; |
| strcpy(res + strlen(target) + 1, rem); |
| token_count = sqfs_count_tokens(res); |
| |
| if (token_count < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| sym_tokens = malloc(token_count * sizeof(char *)); |
| if (!sym_tokens) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Fill tokens list */ |
| ret = sqfs_tokenize(sym_tokens, token_count, res); |
| if (ret) { |
| ret = -EINVAL; |
| goto out; |
| } |
| free(dirs->entry); |
| dirs->entry = NULL; |
| |
| ret = sqfs_search_dir(dirs, sym_tokens, token_count, |
| m_list, m_count); |
| goto out; |
| } else if (!sqfs_is_dir(get_unaligned_le16(&dir->inode_type))) { |
| printf("** Cannot find directory. **\n"); |
| free(dirs->entry); |
| dirs->entry = NULL; |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Check if it is an extended dir. */ |
| if (get_unaligned_le16(&dir->inode_type) == SQFS_LDIR_TYPE) |
| ldir = (struct squashfs_ldir_inode *)table; |
| |
| /* Get dir. offset into the directory table */ |
| offset = sqfs_dir_offset(table, m_list, m_count); |
| dirs->table = &dirs->dir_table[offset]; |
| |
| /* Copy directory header */ |
| memcpy(dirs->dir_header, &dirs->dir_table[offset], |
| SQFS_DIR_HEADER_SIZE); |
| |
| /* Check for empty directory */ |
| if (sqfs_is_empty_dir(table)) { |
| printf("Empty directory.\n"); |
| free(dirs->entry); |
| dirs->entry = NULL; |
| ret = SQFS_EMPTY_DIR; |
| goto out; |
| } |
| |
| dirs->table += SQFS_DIR_HEADER_SIZE; |
| dirs->size = get_unaligned_le16(&dir->file_size); |
| dirs->entry_count = dirs->dir_header->count + 1; |
| dirs->size -= SQFS_DIR_HEADER_SIZE; |
| free(dirs->entry); |
| dirs->entry = NULL; |
| } |
| |
| offset = sqfs_dir_offset(table, m_list, m_count); |
| dirs->table = &dirs->dir_table[offset]; |
| |
| if (get_unaligned_le16(&dir->inode_type) == SQFS_DIR_TYPE) |
| memcpy(&dirs->i_dir, dir, sizeof(*dir)); |
| else |
| memcpy(&dirs->i_ldir, ldir, sizeof(*ldir)); |
| |
| out: |
| free(res); |
| free(rem); |
| free(path); |
| free(target); |
| free(sym_tokens); |
| return ret; |
| } |
| |
| /* |
| * Inode and directory tables are stored as a series of metadata blocks, and |
| * given the compressed size of this table, we can calculate how much metadata |
| * blocks are needed to store the result of the decompression, since a |
| * decompressed metadata block should have a size of 8KiB. |
| */ |
| static int sqfs_count_metablks(void *table, u32 offset, int table_size) |
| { |
| int count = 0, cur_size = 0, ret; |
| u32 data_size; |
| bool comp; |
| |
| do { |
| ret = sqfs_read_metablock(table, offset + cur_size, &comp, |
| &data_size); |
| if (ret) |
| return -EINVAL; |
| cur_size += data_size + SQFS_HEADER_SIZE; |
| count++; |
| } while (cur_size < table_size); |
| |
| return count; |
| } |
| |
| /* |
| * Storing the metadata blocks header's positions will be useful while looking |
| * for an entry in the directory table, using the reference (index and offset) |
| * given by its inode. |
| */ |
| static int sqfs_get_metablk_pos(u32 *pos_list, void *table, u32 offset, |
| int metablks_count) |
| { |
| u32 data_size, cur_size = 0; |
| int j, ret = 0; |
| bool comp; |
| |
| if (!metablks_count) |
| return -EINVAL; |
| |
| for (j = 0; j < metablks_count; j++) { |
| ret = sqfs_read_metablock(table, offset + cur_size, &comp, |
| &data_size); |
| if (ret) |
| return -EINVAL; |
| |
| cur_size += data_size + SQFS_HEADER_SIZE; |
| pos_list[j] = cur_size; |
| } |
| |
| return ret; |
| } |
| |
| static int sqfs_read_inode_table(unsigned char **inode_table) |
| { |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| u64 start, n_blks, table_offset, table_size; |
| int j, ret = 0, metablks_count; |
| unsigned char *src_table, *itb; |
| u32 src_len, dest_offset = 0; |
| unsigned long dest_len = 0; |
| bool compressed; |
| |
| table_size = get_unaligned_le64(&sblk->directory_table_start) - |
| get_unaligned_le64(&sblk->inode_table_start); |
| start = get_unaligned_le64(&sblk->inode_table_start) / |
| ctxt.cur_dev->blksz; |
| n_blks = sqfs_calc_n_blks(sblk->inode_table_start, |
| sblk->directory_table_start, &table_offset); |
| |
| /* Allocate a proper sized buffer (itb) to store the inode table */ |
| itb = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz); |
| if (!itb) |
| return -ENOMEM; |
| |
| if (sqfs_disk_read(start, n_blks, itb) < 0) { |
| ret = -EINVAL; |
| goto free_itb; |
| } |
| |
| /* Parse inode table (metadata block) header */ |
| ret = sqfs_read_metablock(itb, table_offset, &compressed, &src_len); |
| if (ret) { |
| ret = -EINVAL; |
| goto free_itb; |
| } |
| |
| /* Calculate size to store the whole decompressed table */ |
| metablks_count = sqfs_count_metablks(itb, table_offset, table_size); |
| if (metablks_count < 1) { |
| ret = -EINVAL; |
| goto free_itb; |
| } |
| |
| *inode_table = malloc(metablks_count * SQFS_METADATA_BLOCK_SIZE); |
| if (!*inode_table) { |
| ret = -ENOMEM; |
| goto free_itb; |
| } |
| |
| src_table = itb + table_offset + SQFS_HEADER_SIZE; |
| |
| /* Extract compressed Inode table */ |
| for (j = 0; j < metablks_count; j++) { |
| sqfs_read_metablock(itb, table_offset, &compressed, &src_len); |
| if (compressed) { |
| dest_len = SQFS_METADATA_BLOCK_SIZE; |
| ret = sqfs_decompress(&ctxt, *inode_table + |
| dest_offset, &dest_len, |
| src_table, src_len); |
| if (ret) { |
| free(*inode_table); |
| *inode_table = NULL; |
| goto free_itb; |
| } |
| |
| dest_offset += dest_len; |
| } else { |
| memcpy(*inode_table + (j * SQFS_METADATA_BLOCK_SIZE), |
| src_table, src_len); |
| } |
| |
| /* |
| * Offsets to the decompression destination, to the metadata |
| * buffer 'itb' and to the decompression source, respectively. |
| */ |
| |
| table_offset += src_len + SQFS_HEADER_SIZE; |
| src_table += src_len + SQFS_HEADER_SIZE; |
| } |
| |
| free_itb: |
| free(itb); |
| |
| return ret; |
| } |
| |
| static int sqfs_read_directory_table(unsigned char **dir_table, u32 **pos_list) |
| { |
| u64 start, n_blks, table_offset, table_size; |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| int j, ret = 0, metablks_count = -1; |
| unsigned char *src_table, *dtb; |
| u32 src_len, dest_offset = 0; |
| unsigned long dest_len = 0; |
| bool compressed; |
| |
| *dir_table = NULL; |
| *pos_list = NULL; |
| /* DIRECTORY TABLE */ |
| table_size = get_unaligned_le64(&sblk->fragment_table_start) - |
| get_unaligned_le64(&sblk->directory_table_start); |
| start = get_unaligned_le64(&sblk->directory_table_start) / |
| ctxt.cur_dev->blksz; |
| n_blks = sqfs_calc_n_blks(sblk->directory_table_start, |
| sblk->fragment_table_start, &table_offset); |
| |
| /* Allocate a proper sized buffer (dtb) to store the directory table */ |
| dtb = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz); |
| if (!dtb) |
| return -ENOMEM; |
| |
| if (sqfs_disk_read(start, n_blks, dtb) < 0) |
| goto out; |
| |
| /* Parse directory table (metadata block) header */ |
| ret = sqfs_read_metablock(dtb, table_offset, &compressed, &src_len); |
| if (ret) |
| goto out; |
| |
| /* Calculate total size to store the whole decompressed table */ |
| metablks_count = sqfs_count_metablks(dtb, table_offset, table_size); |
| if (metablks_count < 1) |
| goto out; |
| |
| *dir_table = malloc(metablks_count * SQFS_METADATA_BLOCK_SIZE); |
| if (!*dir_table) |
| goto out; |
| |
| *pos_list = malloc(metablks_count * sizeof(u32)); |
| if (!*pos_list) |
| goto out; |
| |
| ret = sqfs_get_metablk_pos(*pos_list, dtb, table_offset, |
| metablks_count); |
| if (ret) { |
| metablks_count = -1; |
| goto out; |
| } |
| |
| src_table = dtb + table_offset + SQFS_HEADER_SIZE; |
| |
| /* Extract compressed Directory table */ |
| dest_offset = 0; |
| for (j = 0; j < metablks_count; j++) { |
| sqfs_read_metablock(dtb, table_offset, &compressed, &src_len); |
| if (compressed) { |
| dest_len = SQFS_METADATA_BLOCK_SIZE; |
| ret = sqfs_decompress(&ctxt, *dir_table + |
| (j * SQFS_METADATA_BLOCK_SIZE), |
| &dest_len, src_table, src_len); |
| if (ret) { |
| metablks_count = -1; |
| goto out; |
| } |
| |
| if (dest_len < SQFS_METADATA_BLOCK_SIZE) { |
| dest_offset += dest_len; |
| break; |
| } |
| |
| dest_offset += dest_len; |
| } else { |
| memcpy(*dir_table + (j * SQFS_METADATA_BLOCK_SIZE), |
| src_table, src_len); |
| } |
| |
| /* |
| * Offsets to the decompression destination, to the metadata |
| * buffer 'dtb' and to the decompression source, respectively. |
| */ |
| table_offset += src_len + SQFS_HEADER_SIZE; |
| src_table += src_len + SQFS_HEADER_SIZE; |
| } |
| |
| out: |
| if (metablks_count < 1) { |
| free(*dir_table); |
| free(*pos_list); |
| *dir_table = NULL; |
| *pos_list = NULL; |
| } |
| free(dtb); |
| |
| return metablks_count; |
| } |
| |
| int sqfs_opendir(const char *filename, struct fs_dir_stream **dirsp) |
| { |
| unsigned char *inode_table = NULL, *dir_table = NULL; |
| int j, token_count = 0, ret = 0, metablks_count; |
| struct squashfs_dir_stream *dirs; |
| char **token_list = NULL, *path = NULL; |
| u32 *pos_list = NULL; |
| |
| dirs = malloc(sizeof(*dirs)); |
| if (!dirs) |
| return -EINVAL; |
| |
| /* these should be set to NULL to prevent dangling pointers */ |
| dirs->dir_header = NULL; |
| dirs->entry = NULL; |
| dirs->table = NULL; |
| dirs->inode_table = NULL; |
| dirs->dir_table = NULL; |
| |
| ret = sqfs_read_inode_table(&inode_table); |
| if (ret) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| metablks_count = sqfs_read_directory_table(&dir_table, &pos_list); |
| if (metablks_count < 1) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Tokenize filename */ |
| token_count = sqfs_count_tokens(filename); |
| if (token_count < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| path = strdup(filename); |
| if (!path) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| token_list = malloc(token_count * sizeof(char *)); |
| if (!token_list) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Fill tokens list */ |
| ret = sqfs_tokenize(token_list, token_count, path); |
| if (ret) |
| goto out; |
| /* |
| * ldir's (extended directory) size is greater than dir, so it works as |
| * a general solution for the malloc size, since 'i' is a union. |
| */ |
| dirs->inode_table = inode_table; |
| dirs->dir_table = dir_table; |
| ret = sqfs_search_dir(dirs, token_list, token_count, pos_list, |
| metablks_count); |
| if (ret) |
| goto out; |
| |
| if (le16_to_cpu(dirs->i_dir.inode_type) == SQFS_DIR_TYPE) |
| dirs->size = le16_to_cpu(dirs->i_dir.file_size); |
| else |
| dirs->size = le32_to_cpu(dirs->i_ldir.file_size); |
| |
| /* Setup directory header */ |
| memcpy(dirs->dir_header, dirs->table, SQFS_DIR_HEADER_SIZE); |
| dirs->entry_count = dirs->dir_header->count + 1; |
| dirs->size -= SQFS_DIR_HEADER_SIZE; |
| |
| /* Setup entry */ |
| dirs->entry = NULL; |
| dirs->table += SQFS_DIR_HEADER_SIZE; |
| |
| *dirsp = (struct fs_dir_stream *)dirs; |
| |
| out: |
| for (j = 0; j < token_count; j++) |
| free(token_list[j]); |
| free(token_list); |
| free(pos_list); |
| free(path); |
| if (ret) { |
| free(inode_table); |
| free(dirs); |
| } |
| |
| return ret; |
| } |
| |
| int sqfs_readdir(struct fs_dir_stream *fs_dirs, struct fs_dirent **dentp) |
| { |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| struct squashfs_dir_stream *dirs; |
| struct squashfs_lreg_inode *lreg; |
| struct squashfs_base_inode *base; |
| struct squashfs_reg_inode *reg; |
| int i_number, offset = 0, ret; |
| struct fs_dirent *dent; |
| unsigned char *ipos; |
| |
| dirs = (struct squashfs_dir_stream *)fs_dirs; |
| if (!dirs->size) { |
| *dentp = NULL; |
| return -SQFS_STOP_READDIR; |
| } |
| |
| dent = &dirs->dentp; |
| |
| if (!dirs->entry_count) { |
| if (dirs->size > SQFS_DIR_HEADER_SIZE) { |
| dirs->size -= SQFS_DIR_HEADER_SIZE; |
| } else { |
| *dentp = NULL; |
| dirs->size = 0; |
| return -SQFS_STOP_READDIR; |
| } |
| |
| if (dirs->size > SQFS_EMPTY_FILE_SIZE) { |
| /* Read follow-up (emitted) dir. header */ |
| memcpy(dirs->dir_header, dirs->table, |
| SQFS_DIR_HEADER_SIZE); |
| dirs->entry_count = dirs->dir_header->count + 1; |
| ret = sqfs_read_entry(&dirs->entry, dirs->table + |
| SQFS_DIR_HEADER_SIZE); |
| if (ret) |
| return -SQFS_STOP_READDIR; |
| |
| dirs->table += SQFS_DIR_HEADER_SIZE; |
| } |
| } else { |
| ret = sqfs_read_entry(&dirs->entry, dirs->table); |
| if (ret) |
| return -SQFS_STOP_READDIR; |
| } |
| |
| i_number = dirs->dir_header->inode_number + dirs->entry->inode_offset; |
| ipos = sqfs_find_inode(dirs->inode_table, i_number, sblk->inodes, |
| sblk->block_size); |
| |
| base = (struct squashfs_base_inode *)ipos; |
| |
| /* Set entry type and size */ |
| switch (dirs->entry->type) { |
| case SQFS_DIR_TYPE: |
| case SQFS_LDIR_TYPE: |
| dent->type = FS_DT_DIR; |
| break; |
| case SQFS_REG_TYPE: |
| case SQFS_LREG_TYPE: |
| /* |
| * Entries do not differentiate extended from regular types, so |
| * it needs to be verified manually. |
| */ |
| if (get_unaligned_le16(&base->inode_type) == SQFS_LREG_TYPE) { |
| lreg = (struct squashfs_lreg_inode *)ipos; |
| dent->size = get_unaligned_le64(&lreg->file_size); |
| } else { |
| reg = (struct squashfs_reg_inode *)ipos; |
| dent->size = get_unaligned_le32(®->file_size); |
| } |
| |
| dent->type = FS_DT_REG; |
| break; |
| case SQFS_BLKDEV_TYPE: |
| case SQFS_CHRDEV_TYPE: |
| case SQFS_LBLKDEV_TYPE: |
| case SQFS_LCHRDEV_TYPE: |
| case SQFS_FIFO_TYPE: |
| case SQFS_SOCKET_TYPE: |
| case SQFS_LFIFO_TYPE: |
| case SQFS_LSOCKET_TYPE: |
| dent->type = SQFS_MISC_ENTRY_TYPE; |
| break; |
| case SQFS_SYMLINK_TYPE: |
| case SQFS_LSYMLINK_TYPE: |
| dent->type = FS_DT_LNK; |
| break; |
| default: |
| return -SQFS_STOP_READDIR; |
| } |
| |
| /* Set entry name */ |
| strncpy(dent->name, dirs->entry->name, dirs->entry->name_size + 1); |
| dent->name[dirs->entry->name_size + 1] = '\0'; |
| |
| offset = dirs->entry->name_size + 1 + SQFS_ENTRY_BASE_LENGTH; |
| dirs->entry_count--; |
| |
| /* Decrement size to be read */ |
| if (dirs->size > offset) |
| dirs->size -= offset; |
| else |
| dirs->size = 0; |
| |
| /* Keep a reference to the current entry before incrementing it */ |
| dirs->table += offset; |
| |
| *dentp = dent; |
| |
| return 0; |
| } |
| |
| int sqfs_probe(struct blk_desc *fs_dev_desc, struct disk_partition *fs_partition) |
| { |
| struct squashfs_super_block *sblk; |
| int ret; |
| |
| ctxt.cur_dev = fs_dev_desc; |
| ctxt.cur_part_info = *fs_partition; |
| |
| ret = sqfs_read_sblk(&sblk); |
| if (ret) |
| goto error; |
| |
| /* Make sure it has a valid SquashFS magic number*/ |
| if (get_unaligned_le32(&sblk->s_magic) != SQFS_MAGIC_NUMBER) { |
| printf("Bad magic number for SquashFS image.\n"); |
| ret = -EINVAL; |
| goto error; |
| } |
| |
| ctxt.sblk = sblk; |
| |
| ret = sqfs_decompressor_init(&ctxt); |
| if (ret) { |
| goto error; |
| } |
| |
| return 0; |
| error: |
| ctxt.cur_dev = NULL; |
| free(ctxt.sblk); |
| ctxt.sblk = NULL; |
| return ret; |
| } |
| |
| static char *sqfs_basename(char *path) |
| { |
| char *fname; |
| |
| fname = path + strlen(path) - 1; |
| while (fname >= path) { |
| if (*fname == '/') { |
| fname++; |
| break; |
| } |
| |
| fname--; |
| } |
| |
| return fname; |
| } |
| |
| static char *sqfs_dirname(char *path) |
| { |
| char *fname; |
| |
| fname = sqfs_basename(path); |
| --fname; |
| *fname = '\0'; |
| |
| return path; |
| } |
| |
| /* |
| * Takes a path to file and splits it in two parts: the filename itself and the |
| * directory's path, e.g.: |
| * path: /path/to/file.txt |
| * file: file.txt |
| * dir: /path/to |
| */ |
| static int sqfs_split_path(char **file, char **dir, const char *path) |
| { |
| char *dirc, *basec, *bname, *dname, *tmp_path; |
| int ret = 0; |
| |
| *file = NULL; |
| *dir = NULL; |
| dirc = NULL; |
| basec = NULL; |
| bname = NULL; |
| dname = NULL; |
| tmp_path = NULL; |
| |
| /* check for first slash in path*/ |
| if (path[0] == '/') { |
| tmp_path = strdup(path); |
| if (!tmp_path) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| } else { |
| tmp_path = malloc(strlen(path) + 2); |
| if (!tmp_path) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| tmp_path[0] = '/'; |
| strcpy(tmp_path + 1, path); |
| } |
| |
| /* String duplicates */ |
| dirc = strdup(tmp_path); |
| if (!dirc) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| basec = strdup(tmp_path); |
| if (!basec) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| dname = sqfs_dirname(dirc); |
| bname = sqfs_basename(basec); |
| |
| *file = strdup(bname); |
| |
| if (!*file) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| if (*dname == '\0') { |
| *dir = malloc(2); |
| if (!*dir) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| (*dir)[0] = '/'; |
| (*dir)[1] = '\0'; |
| } else { |
| *dir = strdup(dname); |
| if (!*dir) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| } |
| |
| out: |
| if (ret) { |
| free(*file); |
| free(*dir); |
| *dir = NULL; |
| *file = NULL; |
| } |
| free(basec); |
| free(dirc); |
| free(tmp_path); |
| |
| return ret; |
| } |
| |
| static int sqfs_get_regfile_info(struct squashfs_reg_inode *reg, |
| struct squashfs_file_info *finfo, |
| struct squashfs_fragment_block_entry *fentry, |
| __le32 blksz) |
| { |
| int datablk_count = 0, ret; |
| |
| finfo->size = get_unaligned_le32(®->file_size); |
| finfo->offset = get_unaligned_le32(®->offset); |
| finfo->start = get_unaligned_le32(®->start_block); |
| finfo->frag = SQFS_IS_FRAGMENTED(get_unaligned_le32(®->fragment)); |
| |
| if (finfo->frag && finfo->offset == 0xFFFFFFFF) |
| return -EINVAL; |
| |
| if (finfo->size < 1 || finfo->start == 0xFFFFFFFF) |
| return -EINVAL; |
| |
| if (finfo->frag) { |
| datablk_count = finfo->size / le32_to_cpu(blksz); |
| ret = sqfs_frag_lookup(get_unaligned_le32(®->fragment), |
| fentry); |
| if (ret < 0) |
| return -EINVAL; |
| finfo->comp = true; |
| if (fentry->size < 1 || fentry->start == 0x7FFFFFFF) |
| return -EINVAL; |
| } else { |
| datablk_count = DIV_ROUND_UP(finfo->size, le32_to_cpu(blksz)); |
| } |
| |
| finfo->blk_sizes = malloc(datablk_count * sizeof(u32)); |
| if (!finfo->blk_sizes) |
| return -ENOMEM; |
| |
| return datablk_count; |
| } |
| |
| static int sqfs_get_lregfile_info(struct squashfs_lreg_inode *lreg, |
| struct squashfs_file_info *finfo, |
| struct squashfs_fragment_block_entry *fentry, |
| __le32 blksz) |
| { |
| int datablk_count = 0, ret; |
| |
| finfo->size = get_unaligned_le64(&lreg->file_size); |
| finfo->offset = get_unaligned_le32(&lreg->offset); |
| finfo->start = get_unaligned_le64(&lreg->start_block); |
| finfo->frag = SQFS_IS_FRAGMENTED(get_unaligned_le32(&lreg->fragment)); |
| |
| if (finfo->frag && finfo->offset == 0xFFFFFFFF) |
| return -EINVAL; |
| |
| if (finfo->size < 1 || finfo->start == 0x7FFFFFFF) |
| return -EINVAL; |
| |
| if (finfo->frag) { |
| datablk_count = finfo->size / le32_to_cpu(blksz); |
| ret = sqfs_frag_lookup(get_unaligned_le32(&lreg->fragment), |
| fentry); |
| if (ret < 0) |
| return -EINVAL; |
| finfo->comp = true; |
| if (fentry->size < 1 || fentry->start == 0x7FFFFFFF) |
| return -EINVAL; |
| } else { |
| datablk_count = DIV_ROUND_UP(finfo->size, le32_to_cpu(blksz)); |
| } |
| |
| finfo->blk_sizes = malloc(datablk_count * sizeof(u32)); |
| if (!finfo->blk_sizes) |
| return -ENOMEM; |
| |
| return datablk_count; |
| } |
| |
| int sqfs_read(const char *filename, void *buf, loff_t offset, loff_t len, |
| loff_t *actread) |
| { |
| char *dir = NULL, *fragment_block, *datablock = NULL, *data_buffer = NULL; |
| char *fragment = NULL, *file = NULL, *resolved, *data; |
| u64 start, n_blks, table_size, data_offset, table_offset; |
| int ret, j, i_number, datablk_count = 0; |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| struct squashfs_fragment_block_entry frag_entry; |
| struct squashfs_file_info finfo = {0}; |
| struct squashfs_symlink_inode *symlink; |
| struct fs_dir_stream *dirsp = NULL; |
| struct squashfs_dir_stream *dirs; |
| struct squashfs_lreg_inode *lreg; |
| struct squashfs_base_inode *base; |
| struct squashfs_reg_inode *reg; |
| unsigned long dest_len; |
| struct fs_dirent *dent; |
| unsigned char *ipos; |
| |
| *actread = 0; |
| |
| if (offset) { |
| /* |
| * TODO: implement reading at an offset in file |
| */ |
| printf("Error: reading at a specific offset in a squashfs file is not supported yet.\n"); |
| return -EINVAL; |
| } |
| |
| /* |
| * sqfs_opendir will uncompress inode and directory tables, and will |
| * return a pointer to the directory that contains the requested file. |
| */ |
| sqfs_split_path(&file, &dir, filename); |
| ret = sqfs_opendir(dir, &dirsp); |
| if (ret) { |
| goto out; |
| } |
| |
| dirs = (struct squashfs_dir_stream *)dirsp; |
| |
| /* For now, only regular files are able to be loaded */ |
| while (!sqfs_readdir(dirsp, &dent)) { |
| ret = strcmp(dent->name, file); |
| if (!ret) |
| break; |
| |
| free(dirs->entry); |
| dirs->entry = NULL; |
| } |
| |
| if (ret) { |
| printf("File not found.\n"); |
| *actread = 0; |
| ret = -ENOENT; |
| goto out; |
| } |
| |
| i_number = dirs->dir_header->inode_number + dirs->entry->inode_offset; |
| ipos = sqfs_find_inode(dirs->inode_table, i_number, sblk->inodes, |
| sblk->block_size); |
| |
| base = (struct squashfs_base_inode *)ipos; |
| switch (get_unaligned_le16(&base->inode_type)) { |
| case SQFS_REG_TYPE: |
| reg = (struct squashfs_reg_inode *)ipos; |
| datablk_count = sqfs_get_regfile_info(reg, &finfo, &frag_entry, |
| sblk->block_size); |
| if (datablk_count < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| memcpy(finfo.blk_sizes, ipos + sizeof(*reg), |
| datablk_count * sizeof(u32)); |
| break; |
| case SQFS_LREG_TYPE: |
| lreg = (struct squashfs_lreg_inode *)ipos; |
| datablk_count = sqfs_get_lregfile_info(lreg, &finfo, |
| &frag_entry, |
| sblk->block_size); |
| if (datablk_count < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| memcpy(finfo.blk_sizes, ipos + sizeof(*lreg), |
| datablk_count * sizeof(u32)); |
| break; |
| case SQFS_SYMLINK_TYPE: |
| case SQFS_LSYMLINK_TYPE: |
| symlink = (struct squashfs_symlink_inode *)ipos; |
| resolved = sqfs_resolve_symlink(symlink, filename); |
| ret = sqfs_read(resolved, buf, offset, len, actread); |
| free(resolved); |
| goto out; |
| case SQFS_BLKDEV_TYPE: |
| case SQFS_CHRDEV_TYPE: |
| case SQFS_LBLKDEV_TYPE: |
| case SQFS_LCHRDEV_TYPE: |
| case SQFS_FIFO_TYPE: |
| case SQFS_SOCKET_TYPE: |
| case SQFS_LFIFO_TYPE: |
| case SQFS_LSOCKET_TYPE: |
| default: |
| printf("Unsupported entry type\n"); |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* If the user specifies a length, check its sanity */ |
| if (len) { |
| if (len > finfo.size) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| finfo.size = len; |
| } else { |
| len = finfo.size; |
| } |
| |
| if (datablk_count) { |
| data_offset = finfo.start; |
| datablock = malloc(get_unaligned_le32(&sblk->block_size)); |
| if (!datablock) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| } |
| |
| for (j = 0; j < datablk_count; j++) { |
| start = data_offset / ctxt.cur_dev->blksz; |
| table_size = SQFS_BLOCK_SIZE(finfo.blk_sizes[j]); |
| table_offset = data_offset - (start * ctxt.cur_dev->blksz); |
| n_blks = DIV_ROUND_UP(table_size + table_offset, |
| ctxt.cur_dev->blksz); |
| |
| data_buffer = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz); |
| |
| if (!data_buffer) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| ret = sqfs_disk_read(start, n_blks, data_buffer); |
| if (ret < 0) { |
| /* |
| * Possible causes: too many data blocks or too large |
| * SquashFS block size. Tip: re-compile the SquashFS |
| * image with mksquashfs's -b <block_size> option. |
| */ |
| printf("Error: too many data blocks to be read.\n"); |
| goto out; |
| } |
| |
| data = data_buffer + table_offset; |
| |
| /* Load the data */ |
| if (SQFS_COMPRESSED_BLOCK(finfo.blk_sizes[j])) { |
| dest_len = get_unaligned_le32(&sblk->block_size); |
| ret = sqfs_decompress(&ctxt, datablock, &dest_len, |
| data, table_size); |
| if (ret) |
| goto out; |
| |
| if ((*actread + dest_len) > len) |
| dest_len = len - *actread; |
| memcpy(buf + *actread, datablock, dest_len); |
| *actread += dest_len; |
| } else { |
| if ((*actread + table_size) > len) |
| table_size = len - *actread; |
| memcpy(buf + *actread, data, table_size); |
| *actread += table_size; |
| } |
| |
| data_offset += table_size; |
| free(data_buffer); |
| data_buffer = NULL; |
| if (*actread >= len) |
| break; |
| } |
| |
| /* |
| * There is no need to continue if the file is not fragmented. |
| */ |
| if (!finfo.frag) { |
| ret = 0; |
| goto out; |
| } |
| |
| start = frag_entry.start / ctxt.cur_dev->blksz; |
| table_size = SQFS_BLOCK_SIZE(frag_entry.size); |
| table_offset = frag_entry.start - (start * ctxt.cur_dev->blksz); |
| n_blks = DIV_ROUND_UP(table_size + table_offset, ctxt.cur_dev->blksz); |
| |
| fragment = malloc_cache_aligned(n_blks * ctxt.cur_dev->blksz); |
| |
| if (!fragment) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| ret = sqfs_disk_read(start, n_blks, fragment); |
| if (ret < 0) |
| goto out; |
| |
| /* File compressed and fragmented */ |
| if (finfo.frag && finfo.comp) { |
| dest_len = get_unaligned_le32(&sblk->block_size); |
| fragment_block = malloc(dest_len); |
| if (!fragment_block) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| ret = sqfs_decompress(&ctxt, fragment_block, &dest_len, |
| (void *)fragment + table_offset, |
| frag_entry.size); |
| if (ret) { |
| free(fragment_block); |
| goto out; |
| } |
| |
| for (j = *actread; j < finfo.size; j++) { |
| memcpy(buf + j, &fragment_block[finfo.offset + j], 1); |
| (*actread)++; |
| } |
| |
| free(fragment_block); |
| |
| } else if (finfo.frag && !finfo.comp) { |
| fragment_block = (void *)fragment + table_offset; |
| |
| for (j = *actread; j < finfo.size; j++) { |
| memcpy(buf + j, &fragment_block[finfo.offset + j], 1); |
| (*actread)++; |
| } |
| } |
| |
| out: |
| free(fragment); |
| if (datablk_count) { |
| free(data_buffer); |
| free(datablock); |
| } |
| free(file); |
| free(dir); |
| free(finfo.blk_sizes); |
| sqfs_closedir(dirsp); |
| |
| return ret; |
| } |
| |
| int sqfs_size(const char *filename, loff_t *size) |
| { |
| struct squashfs_super_block *sblk = ctxt.sblk; |
| struct squashfs_symlink_inode *symlink; |
| struct fs_dir_stream *dirsp = NULL; |
| struct squashfs_base_inode *base; |
| struct squashfs_dir_stream *dirs; |
| struct squashfs_lreg_inode *lreg; |
| struct squashfs_reg_inode *reg; |
| char *dir, *file, *resolved; |
| struct fs_dirent *dent; |
| unsigned char *ipos; |
| int ret, i_number; |
| |
| sqfs_split_path(&file, &dir, filename); |
| /* |
| * sqfs_opendir will uncompress inode and directory tables, and will |
| * return a pointer to the directory that contains the requested file. |
| */ |
| ret = sqfs_opendir(dir, &dirsp); |
| if (ret) { |
| ret = -EINVAL; |
| goto free_strings; |
| } |
| |
| dirs = (struct squashfs_dir_stream *)dirsp; |
| |
| while (!sqfs_readdir(dirsp, &dent)) { |
| ret = strcmp(dent->name, file); |
| if (!ret) |
| break; |
| free(dirs->entry); |
| dirs->entry = NULL; |
| } |
| |
| if (ret) { |
| printf("File not found.\n"); |
| *size = 0; |
| ret = -EINVAL; |
| goto free_strings; |
| } |
| |
| i_number = dirs->dir_header->inode_number + dirs->entry->inode_offset; |
| ipos = sqfs_find_inode(dirs->inode_table, i_number, sblk->inodes, |
| sblk->block_size); |
| free(dirs->entry); |
| dirs->entry = NULL; |
| |
| base = (struct squashfs_base_inode *)ipos; |
| switch (get_unaligned_le16(&base->inode_type)) { |
| case SQFS_REG_TYPE: |
| reg = (struct squashfs_reg_inode *)ipos; |
| *size = get_unaligned_le32(®->file_size); |
| break; |
| case SQFS_LREG_TYPE: |
| lreg = (struct squashfs_lreg_inode *)ipos; |
| *size = get_unaligned_le64(&lreg->file_size); |
| break; |
| case SQFS_SYMLINK_TYPE: |
| case SQFS_LSYMLINK_TYPE: |
| symlink = (struct squashfs_symlink_inode *)ipos; |
| resolved = sqfs_resolve_symlink(symlink, filename); |
| ret = sqfs_size(resolved, size); |
| free(resolved); |
| break; |
| case SQFS_BLKDEV_TYPE: |
| case SQFS_CHRDEV_TYPE: |
| case SQFS_LBLKDEV_TYPE: |
| case SQFS_LCHRDEV_TYPE: |
| case SQFS_FIFO_TYPE: |
| case SQFS_SOCKET_TYPE: |
| case SQFS_LFIFO_TYPE: |
| case SQFS_LSOCKET_TYPE: |
| default: |
| printf("Unable to recover entry's size.\n"); |
| *size = 0; |
| ret = -EINVAL; |
| break; |
| } |
| |
| free_strings: |
| free(dir); |
| free(file); |
| |
| sqfs_closedir(dirsp); |
| |
| return ret; |
| } |
| |
| int sqfs_exists(const char *filename) |
| { |
| struct fs_dir_stream *dirsp = NULL; |
| struct squashfs_dir_stream *dirs; |
| char *dir, *file; |
| struct fs_dirent *dent; |
| int ret; |
| |
| sqfs_split_path(&file, &dir, filename); |
| /* |
| * sqfs_opendir will uncompress inode and directory tables, and will |
| * return a pointer to the directory that contains the requested file. |
| */ |
| ret = sqfs_opendir(dir, &dirsp); |
| if (ret) { |
| ret = -EINVAL; |
| goto free_strings; |
| } |
| |
| dirs = (struct squashfs_dir_stream *)dirsp; |
| |
| while (!sqfs_readdir(dirsp, &dent)) { |
| ret = strcmp(dent->name, file); |
| if (!ret) |
| break; |
| free(dirs->entry); |
| dirs->entry = NULL; |
| } |
| |
| sqfs_closedir(dirsp); |
| |
| free_strings: |
| free(dir); |
| free(file); |
| |
| return ret == 0; |
| } |
| |
| void sqfs_close(void) |
| { |
| sqfs_decompressor_cleanup(&ctxt); |
| free(ctxt.sblk); |
| ctxt.sblk = NULL; |
| ctxt.cur_dev = NULL; |
| } |
| |
| void sqfs_closedir(struct fs_dir_stream *dirs) |
| { |
| struct squashfs_dir_stream *sqfs_dirs; |
| |
| sqfs_dirs = (struct squashfs_dir_stream *)dirs; |
| free(sqfs_dirs->inode_table); |
| free(sqfs_dirs->dir_table); |
| free(sqfs_dirs->dir_header); |
| free(sqfs_dirs); |
| } |