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authorDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2019-08-31 16:59:50 +0200
committerDavid Oberhollenzer <david.oberhollenzer@sigma-star.at>2019-08-31 17:17:23 +0200
commit2ac43d981859bda063e7067371c1cf246c7f81b0 (patch)
treeca289d2b708a60d13e300cc36ae47839389d26cf /lib/sqfs/xattr_reader.c
parent9b3d958fb7c37855a63ed75707281c61dc1d44c4 (diff)
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 <david.oberhollenzer@sigma-star.at>
Diffstat (limited to 'lib/sqfs/xattr_reader.c')
-rw-r--r--lib/sqfs/xattr_reader.c393
1 files changed, 0 insertions, 393 deletions
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 <goliath@infraroot.at>
- */
-#include "config.h"
-
-#include "xattr_reader.h"
-#include "meta_reader.h"
-#include "util.h"
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#include <errno.h>
-
-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;
-}