From 2ac43d981859bda063e7067371c1cf246c7f81b0 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Sat, 31 Aug 2019 16:59:50 +0200 Subject: Split libsquashfs.a into low seperate libraries The idea is to make libsquashfs.a independend of libfstree.a, so it becomes a general purpose squashfs manipulation library. All the high level glue code for libfstree.a and utilites that are overly specific with to tools are moved to a seperate librarby. This commit makes the first step by moving the stuff with dependencies on libfstree to a seperate library. Signed-off-by: David Oberhollenzer --- lib/sqfs/xattr_reader.c | 393 ------------------------------------------------ 1 file changed, 393 deletions(-) delete mode 100644 lib/sqfs/xattr_reader.c (limited to 'lib/sqfs/xattr_reader.c') diff --git a/lib/sqfs/xattr_reader.c b/lib/sqfs/xattr_reader.c deleted file mode 100644 index 399940f..0000000 --- a/lib/sqfs/xattr_reader.c +++ /dev/null @@ -1,393 +0,0 @@ -/* SPDX-License-Identifier: GPL-3.0-or-later */ -/* - * xattr_reader.c - * - * Copyright (C) 2019 David Oberhollenzer - */ -#include "config.h" - -#include "xattr_reader.h" -#include "meta_reader.h" -#include "util.h" - -#include -#include -#include -#include -#include - -struct xattr_reader_t { - uint64_t xattr_start; - - size_t num_id_blocks; - size_t num_ids; - - uint64_t *id_block_starts; - - meta_reader_t *idrd; - meta_reader_t *kvrd; - sqfs_super_t *super; -}; - -static int get_id_block_locations(xattr_reader_t *xr, int sqfsfd, - sqfs_super_t *super) -{ - sqfs_xattr_id_table_t idtbl; - size_t i; - - if (super->xattr_id_table_start >= super->bytes_used) { - fputs("xattr ID location table is after end of filesystem\n", - stderr); - return -1; - } - - if (read_data_at("reading xattr ID location table", - super->xattr_id_table_start, - sqfsfd, &idtbl, sizeof(idtbl))) { - return -1; - } - - xr->xattr_start = le64toh(idtbl.xattr_table_start); - xr->num_ids = le32toh(idtbl.xattr_ids); - xr->num_id_blocks = - (xr->num_ids * sizeof(sqfs_xattr_id_t)) / SQFS_META_BLOCK_SIZE; - - if ((xr->num_ids * sizeof(sqfs_xattr_id_t)) % SQFS_META_BLOCK_SIZE) - xr->num_id_blocks += 1; - - xr->id_block_starts = alloc_array(sizeof(uint64_t), xr->num_id_blocks); - if (xr->id_block_starts == NULL) { - perror("allocating xattr ID location table"); - return -1; - } - - if (read_data_at("reading xattr ID block locations", - super->xattr_id_table_start + sizeof(idtbl), - sqfsfd, xr->id_block_starts, - sizeof(uint64_t) * xr->num_id_blocks)) { - goto fail; - } - - for (i = 0; i < xr->num_id_blocks; ++i) { - xr->id_block_starts[i] = le64toh(xr->id_block_starts[i]); - - if (xr->id_block_starts[i] > super->bytes_used) { - fputs("found xattr ID block that is past " - "end of filesystem\n", stderr); - goto fail; - } - } - - return 0; -fail: - free(xr->id_block_starts); - xr->id_block_starts = NULL; - return -1; -} - -static int get_xattr_desc(xattr_reader_t *xr, uint32_t idx, - sqfs_xattr_id_t *desc) -{ - size_t block, offset; - - if (idx >= xr->num_ids) { - fprintf(stderr, "Tried to access out of bounds " - "xattr index: 0x%08X\n", idx); - return -1; - } - - offset = (idx * sizeof(*desc)) % SQFS_META_BLOCK_SIZE; - block = (idx * sizeof(*desc)) / SQFS_META_BLOCK_SIZE; - - if (meta_reader_seek(xr->idrd, xr->id_block_starts[block], offset)) - return -1; - - if (meta_reader_read(xr->idrd, desc, sizeof(*desc))) - return -1; - - desc->xattr = le64toh(desc->xattr); - desc->count = le32toh(desc->count); - desc->size = le32toh(desc->size); - - if ((desc->xattr & 0xFFFF) >= SQFS_META_BLOCK_SIZE) { - fputs("Found xattr ID record pointing outside " - "metadata block\n", stderr); - return -1; - } - - if ((xr->xattr_start + (desc->xattr >> 16)) >= xr->super->bytes_used) { - fputs("Found xattr ID record pointing past " - "end of filesystem\n", stderr); - return -1; - } - - return 0; -} - -static sqfs_xattr_entry_t *read_key(xattr_reader_t *xr) -{ - sqfs_xattr_entry_t key, *out; - const char *prefix; - size_t plen, total; - - if (meta_reader_read(xr->kvrd, &key, sizeof(key))) - return NULL; - - key.type = le16toh(key.type); - key.size = le16toh(key.size); - - prefix = sqfs_get_xattr_prefix(key.type & SQUASHFS_XATTR_PREFIX_MASK); - if (prefix == NULL) { - fprintf(stderr, "found unknown xattr type %u\n", - key.type & SQUASHFS_XATTR_PREFIX_MASK); - return NULL; - } - - plen = strlen(prefix); - - if (SZ_ADD_OV(plen, key.size, &total) || SZ_ADD_OV(total, 1, &total) || - SZ_ADD_OV(sizeof(*out), total, &total)) { - errno = EOVERFLOW; - goto fail_alloc; - } - - out = calloc(1, total); - if (out == NULL) { - goto fail_alloc; - } - - *out = key; - memcpy(out->key, prefix, plen); - - if (meta_reader_read(xr->kvrd, out->key + plen, key.size)) { - free(out); - return NULL; - } - - return out; -fail_alloc: - perror("allocating xattr key"); - return NULL; -} - -static sqfs_xattr_value_t *read_value(xattr_reader_t *xr, - const sqfs_xattr_entry_t *key) -{ - size_t offset, new_offset, size; - sqfs_xattr_value_t value, *out; - uint64_t ref, start, new_start; - - if (meta_reader_read(xr->kvrd, &value, sizeof(value))) - return NULL; - - if (key->type & SQUASHFS_XATTR_FLAG_OOL) { - if (meta_reader_read(xr->kvrd, &ref, sizeof(ref))) - return NULL; - - meta_reader_get_position(xr->kvrd, &start, &offset); - - new_start = xr->xattr_start + (ref >> 16); - new_offset = ref & 0xFFFF; - - if (new_start > xr->super->bytes_used) { - fputs("OOL xattr reference points past end of " - "filesystem\n", stderr); - return NULL; - } - - if (new_offset >= SQFS_META_BLOCK_SIZE) { - fputs("OOL xattr reference points outside " - "metadata block\n", stderr); - return NULL; - } - - if (meta_reader_seek(xr->kvrd, new_start, new_offset)) - return NULL; - } - - value.size = le32toh(value.size); - - if (SZ_ADD_OV(sizeof(*out), value.size, &size) || - SZ_ADD_OV(size, 1, &size)) { - errno = EOVERFLOW; - goto fail_alloc; - } - - out = calloc(1, size); - if (out == NULL) - goto fail_alloc; - - *out = value; - - if (meta_reader_read(xr->kvrd, out->value, value.size)) - goto fail; - - if (key->type & SQUASHFS_XATTR_FLAG_OOL) { - if (meta_reader_seek(xr->kvrd, start, offset)) - goto fail; - } - - return out; -fail_alloc: - perror("allocating xattr value"); - return NULL; -fail: - free(out); - return NULL; -} - -static int restore_kv_pairs(xattr_reader_t *xr, fstree_t *fs, - tree_node_t *node) -{ - size_t i, key_idx, val_idx; - sqfs_xattr_entry_t *key; - sqfs_xattr_value_t *val; - int ret; - - if (meta_reader_seek(xr->kvrd, node->xattr->block, - node->xattr->offset)) { - return -1; - } - - for (i = 0; i < node->xattr->num_attr; ++i) { - key = read_key(xr); - if (key == NULL) - return -1; - - val = read_value(xr, key); - if (val == NULL) - goto fail_key; - - ret = str_table_get_index(&fs->xattr_keys, - (const char *)key->key, &key_idx); - if (ret) - goto fail_kv; - - ret = str_table_get_index(&fs->xattr_values, - (const char *)val->value, &val_idx); - if (ret) - goto fail_kv; - - if (sizeof(size_t) > sizeof(uint32_t)) { - if (key_idx > 0xFFFFFFFFUL) { - fputs("too many unique xattr keys\n", stderr); - goto fail_kv; - } - - if (val_idx > 0xFFFFFFFFUL) { - fputs("too many unique xattr values\n", stderr); - goto fail_kv; - } - } - - node->xattr->attr[i].key_index = key_idx; - node->xattr->attr[i].value_index = val_idx; - - free(key); - free(val); - } - - return 0; -fail_kv: - free(val); -fail_key: - free(key); - return -1; -} - -int xattr_reader_restore_node(xattr_reader_t *xr, fstree_t *fs, - tree_node_t *node, uint32_t xattr) -{ - sqfs_xattr_id_t desc; - tree_xattr_t *it; - - if (xr->kvrd == NULL || xr->idrd == NULL) - return 0; - - if (xattr == 0xFFFFFFFF) - return 0; - - for (it = fs->xattr; it != NULL; it = it->next) { - if (it->index == xattr) { - node->xattr = it; - return 0; - } - } - - if (get_xattr_desc(xr, xattr, &desc)) - return -1; - - node->xattr = alloc_flex(sizeof(*node->xattr), - sizeof(node->xattr->attr[0]), desc.count); - if (node->xattr == NULL) { - perror("creating xattr structure"); - return -1; - } - - node->xattr->num_attr = desc.count; - node->xattr->max_attr = desc.count; - node->xattr->block = xr->xattr_start + (desc.xattr >> 16); - node->xattr->offset = desc.xattr & 0xFFFF; - node->xattr->size = desc.size; - node->xattr->index = xattr; - node->xattr->owner = node; - - if (restore_kv_pairs(xr, fs, node)) { - free(node->xattr); - return -1; - } - - node->xattr->next = fs->xattr; - fs->xattr = node->xattr; - return 0; -} - -void xattr_reader_destroy(xattr_reader_t *xr) -{ - if (xr->kvrd != NULL) - meta_reader_destroy(xr->kvrd); - - if (xr->idrd != NULL) - meta_reader_destroy(xr->idrd); - - free(xr->id_block_starts); - free(xr); -} - -xattr_reader_t *xattr_reader_create(int sqfsfd, sqfs_super_t *super, - compressor_t *cmp) -{ - xattr_reader_t *xr = calloc(1, sizeof(*xr)); - - if (xr == NULL) { - perror("creating xattr reader"); - return NULL; - } - - if (super->flags & SQFS_FLAG_NO_XATTRS) - return xr; - - if (super->xattr_id_table_start == 0xFFFFFFFFFFFFFFFF) - return xr; - - if (get_id_block_locations(xr, sqfsfd, super)) - goto fail; - - xr->idrd = meta_reader_create(sqfsfd, cmp, - super->id_table_start, - super->bytes_used); - if (xr->idrd == NULL) - goto fail; - - xr->kvrd = meta_reader_create(sqfsfd, cmp, - super->id_table_start, - super->bytes_used); - if (xr->kvrd == NULL) - goto fail; - - xr->super = super; - return xr; -fail: - xattr_reader_destroy(xr); - return NULL; -} -- cgit v1.2.3