bool zip_seek_to_compressed_data(ar_archive_zip *zip)
{
struct zip_entry entry;
if (!ar_seek(zip->super.stream, zip->entry.offset, SEEK_SET))
return false;
if (!zip_parse_local_file_entry(zip, &entry))
return false;
if (zip->entry.method != entry.method) {
warn("Compression methods don't match: %d != %d", zip->entry.method, entry.method);
if (!zip->entry.method)
zip->entry.method = entry.method;
}
if (zip->entry.dosdate != entry.dosdate) {
warn("Timestamps don't match");
if (!zip->entry.dosdate) {
zip->entry.dosdate = entry.dosdate;
zip->super.entry_filetime = ar_conv_dosdate_to_filetime(zip->entry.dosdate);
}
}
return ar_seek(zip->super.stream, zip->entry.offset + ZIP_LOCAL_ENTRY_FIXED_SIZE + entry.namelen + entry.extralen, SEEK_SET);
}
static bool rar_parse_entry(ar_archive *ar, off64_t offset)
{
ar_archive_rar *rar = (ar_archive_rar *)ar;
struct rar_header header;
struct rar_entry entry;
bool out_of_order = offset != ar->entry_offset_next;
if (!ar_seek(ar->stream, offset, SEEK_SET)) {
warn("Couldn't seek to offset %" PRIi64, offset);
return false;
}
for (;;) {
ar->entry_offset = ar_tell(ar->stream);
ar->entry_size_uncompressed = 0;
if (!rar_parse_header(ar, &header))
return false;
ar->entry_offset_next = ar->entry_offset + header.size + header.datasize;
if (ar->entry_offset_next < ar->entry_offset + header.size) {
warn("Integer overflow due to overly large data size");
return false;
}
switch (header.type) {
case TYPE_MAIN_HEADER:
if ((header.flags & MHD_PASSWORD)) {
warn("Encrypted archives aren't supported");
return false;
}
ar_skip(ar->stream, 6 /* reserved data */);
if ((header.flags & MHD_ENCRYPTVER)) {
log("MHD_ENCRYPTVER is set");
ar_skip(ar->stream, 1);
}
if ((header.flags & MHD_COMMENT))
log("MHD_COMMENT is set");
if (ar_tell(ar->stream) - ar->entry_offset > header.size) {
warn("Invalid RAR header size: %d", header.size);
return false;
}
rar->archive_flags = header.flags;
break;
case TYPE_FILE_ENTRY:
if (!rar_parse_header_entry(rar, &header, &entry))
return false;
if ((header.flags & LHD_PASSWORD))
warn("Encrypted entries will fail to uncompress");
if ((header.flags & LHD_DIRECTORY) == LHD_DIRECTORY) {
if (header.datasize == 0) {
log("Skipping directory entry \"%s\"", rar_get_name(ar));
break;
}
warn("Can't skip directory entries containing data");
}
if ((header.flags & (LHD_SPLIT_BEFORE | LHD_SPLIT_AFTER)))
warn("Splitting files isn't really supported");
ar->entry_size_uncompressed = (size_t)entry.size;
ar->entry_filetime = ar_conv_dosdate_to_filetime(entry.dosdate);
if (!rar->entry.solid || rar->entry.method == METHOD_STORE || out_of_order) {
rar_clear_uncompress(&rar->uncomp);
memset(&rar->solid, 0, sizeof(rar->solid));
}
else {
br_clear_leftover_bits(&rar->uncomp);
}
rar->solid.restart = rar->entry.solid && (out_of_order || !rar->solid.part_done);
rar->solid.part_done = !ar->entry_size_uncompressed;
rar->progress.data_left = (size_t)header.datasize;
rar->progress.bytes_done = 0;
rar->progress.crc = 0;
/* TODO: CRC checks don't always hold (claim in XADRARParser.m @readBlockHeader) */
if (!rar_check_header_crc(ar))
warn("Invalid header checksum @%" PRIi64, ar->entry_offset);
if (ar_tell(ar->stream) != ar->entry_offset + rar->entry.header_size) {
warn("Couldn't seek to offset %" PRIi64, ar->entry_offset + rar->entry.header_size);
return false;
}
return true;
case TYPE_NEWSUB:
log("Skipping newsub header @%" PRIi64, ar->entry_offset);
break;
case TYPE_END_OF_ARCHIVE:
ar->at_eof = true;
return false;
default:
log("Unknown RAR header type %02x", header.type);
break;
}
/* TODO: CRC checks don't always hold (claim in XADRARParser.m @readBlockHeader) */
if (!rar_check_header_crc(ar))
warn("Invalid header checksum @%" PRIi64, ar->entry_offset);
if (!ar_seek(ar->stream, ar->entry_offset_next, SEEK_SET)) {
warn("Couldn't seek to offset %" PRIi64, ar->entry_offset_next);
return false;
}
}
}
