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//! Types for reading ZIP archives
#[cfg(feature = "aes-crypto")]
use crate::aes::{AesReader, AesReaderValid};
use crate::compression::CompressionMethod;
use crate::cp437::FromCp437;
use crate::crc32::Crc32Reader;
use crate::result::{InvalidPassword, ZipError, ZipResult};
use crate::spec;
use crate::types::{AesMode, AesVendorVersion, AtomicU64, DateTime, System, ZipFileData};
use crate::zipcrypto::{ZipCryptoReader, ZipCryptoReaderValid, ZipCryptoValidator};
use byteorder::{LittleEndian, ReadBytesExt};
use std::borrow::Cow;
use std::collections::HashMap;
use std::io::{self, prelude::*};
use std::path::{Component, Path};
use std::sync::Arc;
#[cfg(any(
feature = "deflate",
feature = "deflate-miniz",
feature = "deflate-zlib"
))]
use flate2::read::DeflateDecoder;
#[cfg(feature = "bzip2")]
use bzip2::read::BzDecoder;
#[cfg(feature = "zstd")]
use zstd::stream::read::Decoder as ZstdDecoder;
mod ffi {
pub const S_IFDIR: u32 = 0o0040000;
pub const S_IFREG: u32 = 0o0100000;
}
// Put the struct declaration in a private module to convince rustdoc to display ZipArchive nicely
pub(crate) mod zip_archive {
/// Extract immutable data from `ZipArchive` to make it cheap to clone
#[derive(Debug)]
pub(crate) struct Shared {
pub(super) files: Vec<super::ZipFileData>,
pub(super) names_map: super::HashMap<String, usize>,
pub(super) offset: u64,
pub(super) comment: Vec<u8>,
}
/// ZIP archive reader
///
/// At the moment, this type is cheap to clone if this is the case for the
/// reader it uses. However, this is not guaranteed by this crate and it may
/// change in the future.
///
/// ```no_run
/// use std::io::prelude::*;
/// fn list_zip_contents(reader: impl Read + Seek) -> zip::result::ZipResult<()> {
/// let mut zip = zip::ZipArchive::new(reader)?;
///
/// for i in 0..zip.len() {
/// let mut file = zip.by_index(i)?;
/// println!("Filename: {}", file.name());
/// std::io::copy(&mut file, &mut std::io::stdout());
/// }
///
/// Ok(())
/// }
/// ```
#[derive(Clone, Debug)]
pub struct ZipArchive<R> {
pub(super) reader: R,
pub(super) shared: super::Arc<Shared>,
}
}
pub use zip_archive::ZipArchive;
#[allow(clippy::large_enum_variant)]
enum CryptoReader<'a> {
Plaintext(io::Take<&'a mut dyn Read>),
ZipCrypto(ZipCryptoReaderValid<io::Take<&'a mut dyn Read>>),
#[cfg(feature = "aes-crypto")]
Aes {
reader: AesReaderValid<io::Take<&'a mut dyn Read>>,
vendor_version: AesVendorVersion,
},
}
impl<'a> Read for CryptoReader<'a> {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
match self {
CryptoReader::Plaintext(r) => r.read(buf),
CryptoReader::ZipCrypto(r) => r.read(buf),
#[cfg(feature = "aes-crypto")]
CryptoReader::Aes { reader: r, .. } => r.read(buf),
}
}
}
impl<'a> CryptoReader<'a> {
/// Consumes this decoder, returning the underlying reader.
pub fn into_inner(self) -> io::Take<&'a mut dyn Read> {
match self {
CryptoReader::Plaintext(r) => r,
CryptoReader::ZipCrypto(r) => r.into_inner(),
#[cfg(feature = "aes-crypto")]
CryptoReader::Aes { reader: r, .. } => r.into_inner(),
}
}
/// Returns `true` if the data is encrypted using AE2.
pub fn is_ae2_encrypted(&self) -> bool {
#[cfg(feature = "aes-crypto")]
return matches!(
self,
CryptoReader::Aes {
vendor_version: AesVendorVersion::Ae2,
..
}
);
#[cfg(not(feature = "aes-crypto"))]
false
}
}
enum ZipFileReader<'a> {
NoReader,
Raw(io::Take<&'a mut dyn io::Read>),
Stored(Crc32Reader<CryptoReader<'a>>),
#[cfg(any(
feature = "deflate",
feature = "deflate-miniz",
feature = "deflate-zlib"
))]
Deflated(Crc32Reader<flate2::read::DeflateDecoder<CryptoReader<'a>>>),
#[cfg(feature = "bzip2")]
Bzip2(Crc32Reader<BzDecoder<CryptoReader<'a>>>),
#[cfg(feature = "zstd")]
Zstd(Crc32Reader<ZstdDecoder<'a, io::BufReader<CryptoReader<'a>>>>),
}
impl<'a> Read for ZipFileReader<'a> {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
match self {
ZipFileReader::NoReader => panic!("ZipFileReader was in an invalid state"),
ZipFileReader::Raw(r) => r.read(buf),
ZipFileReader::Stored(r) => r.read(buf),
#[cfg(any(
feature = "deflate",
feature = "deflate-miniz",
feature = "deflate-zlib"
))]
ZipFileReader::Deflated(r) => r.read(buf),
#[cfg(feature = "bzip2")]
ZipFileReader::Bzip2(r) => r.read(buf),
#[cfg(feature = "zstd")]
ZipFileReader::Zstd(r) => r.read(buf),
}
}
}
impl<'a> ZipFileReader<'a> {
/// Consumes this decoder, returning the underlying reader.
pub fn into_inner(self) -> io::Take<&'a mut dyn Read> {
match self {
ZipFileReader::NoReader => panic!("ZipFileReader was in an invalid state"),
ZipFileReader::Raw(r) => r,
ZipFileReader::Stored(r) => r.into_inner().into_inner(),
#[cfg(any(
feature = "deflate",
feature = "deflate-miniz",
feature = "deflate-zlib"
))]
ZipFileReader::Deflated(r) => r.into_inner().into_inner().into_inner(),
#[cfg(feature = "bzip2")]
ZipFileReader::Bzip2(r) => r.into_inner().into_inner().into_inner(),
#[cfg(feature = "zstd")]
ZipFileReader::Zstd(r) => r.into_inner().finish().into_inner().into_inner(),
}
}
}
/// A struct for reading a zip file
pub struct ZipFile<'a> {
data: Cow<'a, ZipFileData>,
crypto_reader: Option<CryptoReader<'a>>,
reader: ZipFileReader<'a>,
}
fn find_content<'a>(
data: &ZipFileData,
reader: &'a mut (impl Read + Seek),
) -> ZipResult<io::Take<&'a mut dyn Read>> {
// Parse local header
reader.seek(io::SeekFrom::Start(data.header_start))?;
let signature = reader.read_u32::<LittleEndian>()?;
if signature != spec::LOCAL_FILE_HEADER_SIGNATURE {
return Err(ZipError::InvalidArchive("Invalid local file header"));
}
reader.seek(io::SeekFrom::Current(22))?;
let file_name_length = reader.read_u16::<LittleEndian>()? as u64;
let extra_field_length = reader.read_u16::<LittleEndian>()? as u64;
let magic_and_header = 4 + 22 + 2 + 2;
let data_start = data.header_start + magic_and_header + file_name_length + extra_field_length;
data.data_start.store(data_start);
reader.seek(io::SeekFrom::Start(data_start))?;
Ok((reader as &mut dyn Read).take(data.compressed_size))
}
#[allow(clippy::too_many_arguments)]
fn make_crypto_reader<'a>(
compression_method: crate::compression::CompressionMethod,
crc32: u32,
last_modified_time: DateTime,
using_data_descriptor: bool,
reader: io::Take<&'a mut dyn io::Read>,
password: Option<&[u8]>,
aes_info: Option<(AesMode, AesVendorVersion)>,
#[cfg(feature = "aes-crypto")] compressed_size: u64,
) -> ZipResult<Result<CryptoReader<'a>, InvalidPassword>> {
#[allow(deprecated)]
{
if let CompressionMethod::Unsupported(_) = compression_method {
return unsupported_zip_error("Compression method not supported");
}
}
let reader = match (password, aes_info) {
#[cfg(not(feature = "aes-crypto"))]
(Some(_), Some(_)) => {
return Err(ZipError::UnsupportedArchive(
"AES encrypted files cannot be decrypted without the aes-crypto feature.",
))
}
#[cfg(feature = "aes-crypto")]
(Some(password), Some((aes_mode, vendor_version))) => {
match AesReader::new(reader, aes_mode, compressed_size).validate(password)? {
None => return Ok(Err(InvalidPassword)),
Some(r) => CryptoReader::Aes {
reader: r,
vendor_version,
},
}
}
(Some(password), None) => {
let validator = if using_data_descriptor {
ZipCryptoValidator::InfoZipMsdosTime(last_modified_time.timepart())
} else {
ZipCryptoValidator::PkzipCrc32(crc32)
};
match ZipCryptoReader::new(reader, password).validate(validator)? {
None => return Ok(Err(InvalidPassword)),
Some(r) => CryptoReader::ZipCrypto(r),
}
}
(None, Some(_)) => return Ok(Err(InvalidPassword)),
(None, None) => CryptoReader::Plaintext(reader),
};
Ok(Ok(reader))
}
fn make_reader(
compression_method: CompressionMethod,
crc32: u32,
reader: CryptoReader,
) -> ZipFileReader {
let ae2_encrypted = reader.is_ae2_encrypted();
match compression_method {
CompressionMethod::Stored => {
ZipFileReader::Stored(Crc32Reader::new(reader, crc32, ae2_encrypted))
}
#[cfg(any(
feature = "deflate",
feature = "deflate-miniz",
feature = "deflate-zlib"
))]
CompressionMethod::Deflated => {
let deflate_reader = DeflateDecoder::new(reader);
ZipFileReader::Deflated(Crc32Reader::new(deflate_reader, crc32, ae2_encrypted))
}
#[cfg(feature = "bzip2")]
CompressionMethod::Bzip2 => {
let bzip2_reader = BzDecoder::new(reader);
ZipFileReader::Bzip2(Crc32Reader::new(bzip2_reader, crc32, ae2_encrypted))
}
#[cfg(feature = "zstd")]
CompressionMethod::Zstd => {
let zstd_reader = ZstdDecoder::new(reader).unwrap();
ZipFileReader::Zstd(Crc32Reader::new(zstd_reader, crc32, ae2_encrypted))
}
_ => panic!("Compression method not supported"),
}
}
impl<R: Read + io::Seek> ZipArchive<R> {
/// Get the directory start offset and number of files. This is done in a
/// separate function to ease the control flow design.
pub(crate) fn get_directory_counts(
reader: &mut R,
footer: &spec::CentralDirectoryEnd,
cde_start_pos: u64,
) -> ZipResult<(u64, u64, usize)> {
// See if there's a ZIP64 footer. The ZIP64 locator if present will
// have its signature 20 bytes in front of the standard footer. The
// standard footer, in turn, is 22+N bytes large, where N is the
// comment length. Therefore:
let zip64locator = if reader
.seek(io::SeekFrom::End(
-(20 + 22 + footer.zip_file_comment.len() as i64),
))
.is_ok()
{
match spec::Zip64CentralDirectoryEndLocator::parse(reader) {
Ok(loc) => Some(loc),
Err(ZipError::InvalidArchive(_)) => {
// No ZIP64 header; that's actually fine. We're done here.
None
}
Err(e) => {
// Yikes, a real problem
return Err(e);
}
}
} else {
// Empty Zip files will have nothing else so this error might be fine. If
// not, we'll find out soon.
None
};
match zip64locator {
None => {
// Some zip files have data prepended to them, resulting in the
// offsets all being too small. Get the amount of error by comparing
// the actual file position we found the CDE at with the offset
// recorded in the CDE.
let archive_offset = cde_start_pos
.checked_sub(footer.central_directory_size as u64)
.and_then(|x| x.checked_sub(footer.central_directory_offset as u64))
.ok_or(ZipError::InvalidArchive(
"Invalid central directory size or offset",
))?;
let directory_start = footer.central_directory_offset as u64 + archive_offset;
let number_of_files = footer.number_of_files_on_this_disk as usize;
Ok((archive_offset, directory_start, number_of_files))
}
Some(locator64) => {
// If we got here, this is indeed a ZIP64 file.
if !footer.record_too_small()
&& footer.disk_number as u32 != locator64.disk_with_central_directory
{
return unsupported_zip_error(
"Support for multi-disk files is not implemented",
);
}
// We need to reassess `archive_offset`. We know where the ZIP64
// central-directory-end structure *should* be, but unfortunately we
// don't know how to precisely relate that location to our current
// actual offset in the file, since there may be junk at its
// beginning. Therefore we need to perform another search, as in
// read::CentralDirectoryEnd::find_and_parse, except now we search
// forward.
let search_upper_bound = cde_start_pos
.checked_sub(60) // minimum size of Zip64CentralDirectoryEnd + Zip64CentralDirectoryEndLocator
.ok_or(ZipError::InvalidArchive(
"File cannot contain ZIP64 central directory end",
))?;
let (footer, archive_offset) = spec::Zip64CentralDirectoryEnd::find_and_parse(
reader,
locator64.end_of_central_directory_offset,
search_upper_bound,
)?;
if footer.disk_number != footer.disk_with_central_directory {
return unsupported_zip_error(
"Support for multi-disk files is not implemented",
);
}
let directory_start = footer
.central_directory_offset
.checked_add(archive_offset)
.ok_or({
ZipError::InvalidArchive("Invalid central directory size or offset")
})?;
Ok((
archive_offset,
directory_start,
footer.number_of_files as usize,
))
}
}
}
/// Read a ZIP archive, collecting the files it contains
///
/// This uses the central directory record of the ZIP file, and ignores local file headers
pub fn new(mut reader: R) -> ZipResult<ZipArchive<R>> {
let (footer, cde_start_pos) = spec::CentralDirectoryEnd::find_and_parse(&mut reader)?;
if !footer.record_too_small() && footer.disk_number != footer.disk_with_central_directory {
return unsupported_zip_error("Support for multi-disk files is not implemented");
}
let (archive_offset, directory_start, number_of_files) =
Self::get_directory_counts(&mut reader, &footer, cde_start_pos)?;
// If the parsed number of files is greater than the offset then
// something fishy is going on and we shouldn't trust number_of_files.
let file_capacity = if number_of_files > cde_start_pos as usize {
0
} else {
number_of_files
};
let mut files = Vec::with_capacity(file_capacity);
let mut names_map = HashMap::with_capacity(file_capacity);
if reader.seek(io::SeekFrom::Start(directory_start)).is_err() {
return Err(ZipError::InvalidArchive(
"Could not seek to start of central directory",
));
}
for _ in 0..number_of_files {
let file = central_header_to_zip_file(&mut reader, archive_offset)?;
names_map.insert(file.file_name.clone(), files.len());
files.push(file);
}
let shared = Arc::new(zip_archive::Shared {
files,
names_map,
offset: archive_offset,
comment: footer.zip_file_comment,
});
Ok(ZipArchive { reader, shared })
}
/// Extract a Zip archive into a directory, overwriting files if they
/// already exist. Paths are sanitized with [`ZipFile::enclosed_name`].
///
/// Extraction is not atomic; If an error is encountered, some of the files
/// may be left on disk.
pub fn extract<P: AsRef<Path>>(&mut self, directory: P) -> ZipResult<()> {
use std::fs;
for i in 0..self.len() {
let mut file = self.by_index(i)?;
let filepath = file
.enclosed_name()
.ok_or(ZipError::InvalidArchive("Invalid file path"))?;
let outpath = directory.as_ref().join(filepath);
if file.name().ends_with('/') {
fs::create_dir_all(&outpath)?;
} else {
if let Some(p) = outpath.parent() {
if !p.exists() {
fs::create_dir_all(p)?;
}
}
let mut outfile = fs::File::create(&outpath)?;
io::copy(&mut file, &mut outfile)?;
}
// Get and Set permissions
#[cfg(unix)]
{
use std::os::unix::fs::PermissionsExt;
if let Some(mode) = file.unix_mode() {
fs::set_permissions(&outpath, fs::Permissions::from_mode(mode))?;
}
}
}
Ok(())
}
/// Number of files contained in this zip.
pub fn len(&self) -> usize {
self.shared.files.len()
}
/// Whether this zip archive contains no files
pub fn is_empty(&self) -> bool {
self.len() == 0
}
/// Get the offset from the beginning of the underlying reader that this zip begins at, in bytes.
///
/// Normally this value is zero, but if the zip has arbitrary data prepended to it, then this value will be the size
/// of that prepended data.
pub fn offset(&self) -> u64 {
self.shared.offset
}
/// Get the comment of the zip archive.
pub fn comment(&self) -> &[u8] {
&self.shared.comment
}
/// Returns an iterator over all the file and directory names in this archive.
pub fn file_names(&self) -> impl Iterator<Item = &str> {
self.shared.names_map.keys().map(|s| s.as_str())
}
/// Search for a file entry by name, decrypt with given password
///
/// # Warning
///
/// The implementation of the cryptographic algorithms has not
/// gone through a correctness review, and you should assume it is insecure:
/// passwords used with this API may be compromised.
///
/// This function sometimes accepts wrong password. This is because the ZIP spec only allows us
/// to check for a 1/256 chance that the password is correct.
/// There are many passwords out there that will also pass the validity checks
/// we are able to perform. This is a weakness of the ZipCrypto algorithm,
/// due to its fairly primitive approach to cryptography.
pub fn by_name_decrypt<'a>(
&'a mut self,
name: &str,
password: &[u8],
) -> ZipResult<Result<ZipFile<'a>, InvalidPassword>> {
self.by_name_with_optional_password(name, Some(password))
}
/// Search for a file entry by name
pub fn by_name<'a>(&'a mut self, name: &str) -> ZipResult<ZipFile<'a>> {
Ok(self.by_name_with_optional_password(name, None)?.unwrap())
}
fn by_name_with_optional_password<'a>(
&'a mut self,
name: &str,
password: Option<&[u8]>,
) -> ZipResult<Result<ZipFile<'a>, InvalidPassword>> {
let index = match self.shared.names_map.get(name) {
Some(index) => *index,
None => {
return Err(ZipError::FileNotFound);
}
};
self.by_index_with_optional_password(index, password)
}
/// Get a contained file by index, decrypt with given password
///
/// # Warning
///
/// The implementation of the cryptographic algorithms has not
/// gone through a correctness review, and you should assume it is insecure:
/// passwords used with this API may be compromised.
///
/// This function sometimes accepts wrong password. This is because the ZIP spec only allows us
/// to check for a 1/256 chance that the password is correct.
/// There are many passwords out there that will also pass the validity checks
/// we are able to perform. This is a weakness of the ZipCrypto algorithm,
/// due to its fairly primitive approach to cryptography.
pub fn by_index_decrypt<'a>(
&'a mut self,
file_number: usize,
password: &[u8],
) -> ZipResult<Result<ZipFile<'a>, InvalidPassword>> {
self.by_index_with_optional_password(file_number, Some(password))
}
/// Get a contained file by index
pub fn by_index(&mut self, file_number: usize) -> ZipResult<ZipFile<'_>> {
Ok(self
.by_index_with_optional_password(file_number, None)?
.unwrap())
}
/// Get a contained file by index without decompressing it
pub fn by_index_raw(&mut self, file_number: usize) -> ZipResult<ZipFile<'_>> {
let reader = &mut self.reader;
self.shared
.files
.get(file_number)
.ok_or(ZipError::FileNotFound)
.and_then(move |data| {
Ok(ZipFile {
crypto_reader: None,
reader: ZipFileReader::Raw(find_content(data, reader)?),
data: Cow::Borrowed(data),
})
})
}
fn by_index_with_optional_password<'a>(
&'a mut self,
file_number: usize,
mut password: Option<&[u8]>,
) -> ZipResult<Result<ZipFile<'a>, InvalidPassword>> {
let data = self
.shared
.files
.get(file_number)
.ok_or(ZipError::FileNotFound)?;
match (password, data.encrypted) {
(None, true) => return Err(ZipError::UnsupportedArchive(ZipError::PASSWORD_REQUIRED)),
(Some(_), false) => password = None, //Password supplied, but none needed! Discard.
_ => {}
}
let limit_reader = find_content(data, &mut self.reader)?;
match make_crypto_reader(
data.compression_method,
data.crc32,
data.last_modified_time,
data.using_data_descriptor,
limit_reader,
password,
data.aes_mode,
#[cfg(feature = "aes-crypto")]
data.compressed_size,
) {
Ok(Ok(crypto_reader)) => Ok(Ok(ZipFile {
crypto_reader: Some(crypto_reader),
reader: ZipFileReader::NoReader,
data: Cow::Borrowed(data),
})),
Err(e) => Err(e),
Ok(Err(e)) => Ok(Err(e)),
}
}
/// Unwrap and return the inner reader object
///
/// The position of the reader is undefined.
pub fn into_inner(self) -> R {
self.reader
}
}
fn unsupported_zip_error<T>(detail: &'static str) -> ZipResult<T> {
Err(ZipError::UnsupportedArchive(detail))
}
/// Parse a central directory entry to collect the information for the file.
pub(crate) fn central_header_to_zip_file<R: Read + io::Seek>(
reader: &mut R,
archive_offset: u64,
) -> ZipResult<ZipFileData> {
let central_header_start = reader.stream_position()?;
// Parse central header
let signature = reader.read_u32::<LittleEndian>()?;
if signature != spec::CENTRAL_DIRECTORY_HEADER_SIGNATURE {
return Err(ZipError::InvalidArchive("Invalid Central Directory header"));
}
let version_made_by = reader.read_u16::<LittleEndian>()?;
let _version_to_extract = reader.read_u16::<LittleEndian>()?;
let flags = reader.read_u16::<LittleEndian>()?;
let encrypted = flags & 1 == 1;
let is_utf8 = flags & (1 << 11) != 0;
let using_data_descriptor = flags & (1 << 3) != 0;
let compression_method = reader.read_u16::<LittleEndian>()?;
let last_mod_time = reader.read_u16::<LittleEndian>()?;
let last_mod_date = reader.read_u16::<LittleEndian>()?;
let crc32 = reader.read_u32::<LittleEndian>()?;
let compressed_size = reader.read_u32::<LittleEndian>()?;
let uncompressed_size = reader.read_u32::<LittleEndian>()?;
let file_name_length = reader.read_u16::<LittleEndian>()? as usize;
let extra_field_length = reader.read_u16::<LittleEndian>()? as usize;
let file_comment_length = reader.read_u16::<LittleEndian>()? as usize;
let _disk_number = reader.read_u16::<LittleEndian>()?;
let _internal_file_attributes = reader.read_u16::<LittleEndian>()?;
let external_file_attributes = reader.read_u32::<LittleEndian>()?;
let offset = reader.read_u32::<LittleEndian>()? as u64;
let mut file_name_raw = vec![0; file_name_length];
reader.read_exact(&mut file_name_raw)?;
let mut extra_field = vec![0; extra_field_length];
reader.read_exact(&mut extra_field)?;
let mut file_comment_raw = vec![0; file_comment_length];
reader.read_exact(&mut file_comment_raw)?;
let file_name = match is_utf8 {
true => String::from_utf8_lossy(&file_name_raw).into_owned(),
false => file_name_raw.clone().from_cp437(),
};
let file_comment = match is_utf8 {
true => String::from_utf8_lossy(&file_comment_raw).into_owned(),
false => file_comment_raw.from_cp437(),
};
// Construct the result
let mut result = ZipFileData {
system: System::from_u8((version_made_by >> 8) as u8),
version_made_by: version_made_by as u8,
encrypted,
using_data_descriptor,
compression_method: {
#[allow(deprecated)]
CompressionMethod::from_u16(compression_method)
},
compression_level: None,
last_modified_time: DateTime::from_msdos(last_mod_date, last_mod_time),
crc32,
compressed_size: compressed_size as u64,
uncompressed_size: uncompressed_size as u64,
file_name,
file_name_raw,
extra_field,
file_comment,
header_start: offset,
central_header_start,
data_start: AtomicU64::new(0),
external_attributes: external_file_attributes,
large_file: false,
aes_mode: None,
};
match parse_extra_field(&mut result) {
Ok(..) | Err(ZipError::Io(..)) => {}
Err(e) => return Err(e),
}
let aes_enabled = result.compression_method == CompressionMethod::AES;
if aes_enabled && result.aes_mode.is_none() {
return Err(ZipError::InvalidArchive(
"AES encryption without AES extra data field",
));
}
// Account for shifted zip offsets.
result.header_start = result
.header_start
.checked_add(archive_offset)
.ok_or(ZipError::InvalidArchive("Archive header is too large"))?;
Ok(result)
}
fn parse_extra_field(file: &mut ZipFileData) -> ZipResult<()> {
let mut reader = io::Cursor::new(&file.extra_field);
while (reader.position() as usize) < file.extra_field.len() {
let kind = reader.read_u16::<LittleEndian>()?;
let len = reader.read_u16::<LittleEndian>()?;
let mut len_left = len as i64;
match kind {
// Zip64 extended information extra field
0x0001 => {
if file.uncompressed_size == spec::ZIP64_BYTES_THR {
file.large_file = true;
file.uncompressed_size = reader.read_u64::<LittleEndian>()?;
len_left -= 8;
}
if file.compressed_size == spec::ZIP64_BYTES_THR {
file.large_file = true;
file.compressed_size = reader.read_u64::<LittleEndian>()?;
len_left -= 8;
}
if file.header_start == spec::ZIP64_BYTES_THR {
file.header_start = reader.read_u64::<LittleEndian>()?;
len_left -= 8;
}
}
0x9901 => {
// AES
if len != 7 {
return Err(ZipError::UnsupportedArchive(
"AES extra data field has an unsupported length",
));
}
let vendor_version = reader.read_u16::<LittleEndian>()?;
let vendor_id = reader.read_u16::<LittleEndian>()?;
let aes_mode = reader.read_u8()?;
let compression_method = reader.read_u16::<LittleEndian>()?;
if vendor_id != 0x4541 {
return Err(ZipError::InvalidArchive("Invalid AES vendor"));
}
let vendor_version = match vendor_version {
0x0001 => AesVendorVersion::Ae1,
0x0002 => AesVendorVersion::Ae2,
_ => return Err(ZipError::InvalidArchive("Invalid AES vendor version")),
};
match aes_mode {
0x01 => file.aes_mode = Some((AesMode::Aes128, vendor_version)),
0x02 => file.aes_mode = Some((AesMode::Aes192, vendor_version)),
0x03 => file.aes_mode = Some((AesMode::Aes256, vendor_version)),
_ => return Err(ZipError::InvalidArchive("Invalid AES encryption strength")),
};
file.compression_method = {
#[allow(deprecated)]
CompressionMethod::from_u16(compression_method)
};
}
_ => {
// Other fields are ignored
}
}
// We could also check for < 0 to check for errors
if len_left > 0 {
reader.seek(io::SeekFrom::Current(len_left))?;
}
}
Ok(())
}
/// Methods for retrieving information on zip files
impl<'a> ZipFile<'a> {
fn get_reader(&mut self) -> &mut ZipFileReader<'a> {
if let ZipFileReader::NoReader = self.reader {
let data = &self.data;
let crypto_reader = self.crypto_reader.take().expect("Invalid reader state");
self.reader = make_reader(data.compression_method, data.crc32, crypto_reader)
}
&mut self.reader
}
pub(crate) fn get_raw_reader(&mut self) -> &mut dyn Read {
if let ZipFileReader::NoReader = self.reader {
let crypto_reader = self.crypto_reader.take().expect("Invalid reader state");
self.reader = ZipFileReader::Raw(crypto_reader.into_inner())
}
&mut self.reader
}
/// Get the version of the file
pub fn version_made_by(&self) -> (u8, u8) {
(
self.data.version_made_by / 10,
self.data.version_made_by % 10,
)
}
/// Get the name of the file
///
/// # Warnings
///
/// It is dangerous to use this name directly when extracting an archive.
/// It may contain an absolute path (`/etc/shadow`), or break out of the
/// current directory (`../runtime`). Carelessly writing to these paths
/// allows an attacker to craft a ZIP archive that will overwrite critical
/// files.
///
/// You can use the [`ZipFile::enclosed_name`] method to validate the name
/// as a safe path.
pub fn name(&self) -> &str {
&self.data.file_name
}
/// Get the name of the file, in the raw (internal) byte representation.
///
/// The encoding of this data is currently undefined.
pub fn name_raw(&self) -> &[u8] {
&self.data.file_name_raw
}
/// Get the name of the file in a sanitized form. It truncates the name to the first NULL byte,
/// removes a leading '/' and removes '..' parts.
#[deprecated(
since = "0.5.7",
note = "by stripping `..`s from the path, the meaning of paths can change.
`mangled_name` can be used if this behaviour is desirable"
)]
pub fn sanitized_name(&self) -> ::std::path::PathBuf {
self.mangled_name()
}
/// Rewrite the path, ignoring any path components with special meaning.
///
/// - Absolute paths are made relative
/// - [`ParentDir`]s are ignored
/// - Truncates the filename at a NULL byte
///
/// This is appropriate if you need to be able to extract *something* from
/// any archive, but will easily misrepresent trivial paths like
/// `foo/../bar` as `foo/bar` (instead of `bar`). Because of this,
/// [`ZipFile::enclosed_name`] is the better option in most scenarios.
///
/// [`ParentDir`]: `Component::ParentDir`
pub fn mangled_name(&self) -> ::std::path::PathBuf {
self.data.file_name_sanitized()
}
/// Ensure the file path is safe to use as a [`Path`].
///
/// - It can't contain NULL bytes
/// - It can't resolve to a path outside the current directory
/// > `foo/../bar` is fine, `foo/../../bar` is not.
/// - It can't be an absolute path
///
/// This will read well-formed ZIP files correctly, and is resistant
/// to path-based exploits. It is recommended over
/// [`ZipFile::mangled_name`].
pub fn enclosed_name(&self) -> Option<&Path> {
if self.data.file_name.contains('\0') {
return None;
}
let path = Path::new(&self.data.file_name);
let mut depth = 0usize;
for component in path.components() {
match component {
Component::Prefix(_) | Component::RootDir => return None,
Component::ParentDir => depth = depth.checked_sub(1)?,
Component::Normal(_) => depth += 1,
Component::CurDir => (),
}
}
Some(path)
}
/// Get the comment of the file
pub fn comment(&self) -> &str {
&self.data.file_comment
}
/// Get the compression method used to store the file
pub fn compression(&self) -> CompressionMethod {
self.data.compression_method
}
/// Get the size of the file, in bytes, in the archive
pub fn compressed_size(&self) -> u64 {
self.data.compressed_size
}
/// Get the size of the file, in bytes, when uncompressed
pub fn size(&self) -> u64 {
self.data.uncompressed_size
}
/// Get the time the file was last modified
pub fn last_modified(&self) -> DateTime {
self.data.last_modified_time
}
/// Returns whether the file is actually a directory
pub fn is_dir(&self) -> bool {
self.name()
.chars()
.rev()
.next()
.map_or(false, |c| c == '/' || c == '\\')
}
/// Returns whether the file is a regular file
pub fn is_file(&self) -> bool {
!self.is_dir()
}
/// Get unix mode for the file
pub fn unix_mode(&self) -> Option<u32> {
if self.data.external_attributes == 0 {
return None;
}
match self.data.system {
System::Unix => Some(self.data.external_attributes >> 16),
System::Dos => {
// Interpret MS-DOS directory bit
let mut mode = if 0x10 == (self.data.external_attributes & 0x10) {
ffi::S_IFDIR | 0o0775
} else {
ffi::S_IFREG | 0o0664
};
if 0x01 == (self.data.external_attributes & 0x01) {
// Read-only bit; strip write permissions
mode &= 0o0555;
}
Some(mode)
}
_ => None,
}
}
/// Get the CRC32 hash of the original file
pub fn crc32(&self) -> u32 {
self.data.crc32
}
/// Get the extra data of the zip header for this file
pub fn extra_data(&self) -> &[u8] {
&self.data.extra_field
}
/// Get the starting offset of the data of the compressed file
pub fn data_start(&self) -> u64 {
self.data.data_start.load()
}
/// Get the starting offset of the zip header for this file
pub fn header_start(&self) -> u64 {
self.data.header_start
}
/// Get the starting offset of the zip header in the central directory for this file
pub fn central_header_start(&self) -> u64 {
self.data.central_header_start
}
}
impl<'a> Read for ZipFile<'a> {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
self.get_reader().read(buf)
}
}
impl<'a> Drop for ZipFile<'a> {
fn drop(&mut self) {
// self.data is Owned, this reader is constructed by a streaming reader.
// In this case, we want to exhaust the reader so that the next file is accessible.
if let Cow::Owned(_) = self.data {
let mut buffer = [0; 1 << 16];
// Get the inner `Take` reader so all decryption, decompression and CRC calculation is skipped.
let mut reader: std::io::Take<&mut dyn std::io::Read> = match &mut self.reader {
ZipFileReader::NoReader => {
let innerreader = ::std::mem::replace(&mut self.crypto_reader, None);
innerreader.expect("Invalid reader state").into_inner()
}
reader => {
let innerreader = ::std::mem::replace(reader, ZipFileReader::NoReader);
innerreader.into_inner()
}
};
loop {
match reader.read(&mut buffer) {
Ok(0) => break,
Ok(_) => (),
Err(e) => panic!(
"Could not consume all of the output of the current ZipFile: {:?}",
e
),
}
}
}
}
}
/// Read ZipFile structures from a non-seekable reader.
///
/// This is an alternative method to read a zip file. If possible, use the ZipArchive functions
/// as some information will be missing when reading this manner.
///
/// Reads a file header from the start of the stream. Will return `Ok(Some(..))` if a file is
/// present at the start of the stream. Returns `Ok(None)` if the start of the central directory
/// is encountered. No more files should be read after this.
///
/// The Drop implementation of ZipFile ensures that the reader will be correctly positioned after
/// the structure is done.
///
/// Missing fields are:
/// * `comment`: set to an empty string
/// * `data_start`: set to 0
/// * `external_attributes`: `unix_mode()`: will return None
pub fn read_zipfile_from_stream<'a, R: io::Read>(
reader: &'a mut R,
) -> ZipResult<Option<ZipFile<'_>>> {
let signature = reader.read_u32::<LittleEndian>()?;
match signature {
spec::LOCAL_FILE_HEADER_SIGNATURE => (),
spec::CENTRAL_DIRECTORY_HEADER_SIGNATURE => return Ok(None),
_ => return Err(ZipError::InvalidArchive("Invalid local file header")),
}
let version_made_by = reader.read_u16::<LittleEndian>()?;
let flags = reader.read_u16::<LittleEndian>()?;
let encrypted = flags & 1 == 1;
let is_utf8 = flags & (1 << 11) != 0;
let using_data_descriptor = flags & (1 << 3) != 0;
#[allow(deprecated)]
let compression_method = CompressionMethod::from_u16(reader.read_u16::<LittleEndian>()?);
let last_mod_time = reader.read_u16::<LittleEndian>()?;
let last_mod_date = reader.read_u16::<LittleEndian>()?;
let crc32 = reader.read_u32::<LittleEndian>()?;
let compressed_size = reader.read_u32::<LittleEndian>()?;
let uncompressed_size = reader.read_u32::<LittleEndian>()?;
let file_name_length = reader.read_u16::<LittleEndian>()? as usize;
let extra_field_length = reader.read_u16::<LittleEndian>()? as usize;
let mut file_name_raw = vec![0; file_name_length];
reader.read_exact(&mut file_name_raw)?;
let mut extra_field = vec![0; extra_field_length];
reader.read_exact(&mut extra_field)?;
let file_name = match is_utf8 {
true => String::from_utf8_lossy(&file_name_raw).into_owned(),
false => file_name_raw.clone().from_cp437(),
};
let mut result = ZipFileData {
system: System::from_u8((version_made_by >> 8) as u8),
version_made_by: version_made_by as u8,
encrypted,
using_data_descriptor,
compression_method,
compression_level: None,
last_modified_time: DateTime::from_msdos(last_mod_date, last_mod_time),
crc32,
compressed_size: compressed_size as u64,
uncompressed_size: uncompressed_size as u64,
file_name,
file_name_raw,
extra_field,
file_comment: String::new(), // file comment is only available in the central directory
// header_start and data start are not available, but also don't matter, since seeking is
// not available.
header_start: 0,
data_start: AtomicU64::new(0),
central_header_start: 0,
// The external_attributes field is only available in the central directory.
// We set this to zero, which should be valid as the docs state 'If input came
// from standard input, this field is set to zero.'
external_attributes: 0,
large_file: false,
aes_mode: None,
};
match parse_extra_field(&mut result) {
Ok(..) | Err(ZipError::Io(..)) => {}
Err(e) => return Err(e),
}
if encrypted {
return unsupported_zip_error("Encrypted files are not supported");
}
if using_data_descriptor {
return unsupported_zip_error("The file length is not available in the local header");
}
let limit_reader = (reader as &'a mut dyn io::Read).take(result.compressed_size);
let result_crc32 = result.crc32;
let result_compression_method = result.compression_method;
let crypto_reader = make_crypto_reader(
result_compression_method,
result_crc32,
result.last_modified_time,
result.using_data_descriptor,
limit_reader,
None,
None,
#[cfg(feature = "aes-crypto")]
result.compressed_size,
)?
.unwrap();
Ok(Some(ZipFile {
data: Cow::Owned(result),
crypto_reader: None,
reader: make_reader(result_compression_method, result_crc32, crypto_reader),
}))
}
#[cfg(test)]
mod test {
#[test]
fn invalid_offset() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/invalid_offset.zip"));
let reader = ZipArchive::new(io::Cursor::new(v));
assert!(reader.is_err());
}
#[test]
fn invalid_offset2() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/invalid_offset2.zip"));
let reader = ZipArchive::new(io::Cursor::new(v));
assert!(reader.is_err());
}
#[test]
fn zip64_with_leading_junk() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/zip64_demo.zip"));
let reader = ZipArchive::new(io::Cursor::new(v)).unwrap();
assert_eq!(reader.len(), 1);
}
#[test]
fn zip_contents() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/mimetype.zip"));
let mut reader = ZipArchive::new(io::Cursor::new(v)).unwrap();
assert_eq!(reader.comment(), b"");
assert_eq!(reader.by_index(0).unwrap().central_header_start(), 77);
}
#[test]
fn zip_read_streaming() {
use super::read_zipfile_from_stream;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/mimetype.zip"));
let mut reader = io::Cursor::new(v);
loop {
if read_zipfile_from_stream(&mut reader).unwrap().is_none() {
break;
}
}
}
#[test]
fn zip_clone() {
use super::ZipArchive;
use std::io::{self, Read};
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/mimetype.zip"));
let mut reader1 = ZipArchive::new(io::Cursor::new(v)).unwrap();
let mut reader2 = reader1.clone();
let mut file1 = reader1.by_index(0).unwrap();
let mut file2 = reader2.by_index(0).unwrap();
let t = file1.last_modified();
assert_eq!(
(
t.year(),
t.month(),
t.day(),
t.hour(),
t.minute(),
t.second()
),
(1980, 1, 1, 0, 0, 0)
);
let mut buf1 = [0; 5];
let mut buf2 = [0; 5];
let mut buf3 = [0; 5];
let mut buf4 = [0; 5];
file1.read_exact(&mut buf1).unwrap();
file2.read_exact(&mut buf2).unwrap();
file1.read_exact(&mut buf3).unwrap();
file2.read_exact(&mut buf4).unwrap();
assert_eq!(buf1, buf2);
assert_eq!(buf3, buf4);
assert_ne!(buf1, buf3);
}
#[test]
fn file_and_dir_predicates() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!("../tests/data/files_and_dirs.zip"));
let mut zip = ZipArchive::new(io::Cursor::new(v)).unwrap();
for i in 0..zip.len() {
let zip_file = zip.by_index(i).unwrap();
let full_name = zip_file.enclosed_name().unwrap();
let file_name = full_name.file_name().unwrap().to_str().unwrap();
assert!(
(file_name.starts_with("dir") && zip_file.is_dir())
|| (file_name.starts_with("file") && zip_file.is_file())
);
}
}
/// test case to ensure we don't preemptively over allocate based on the
/// declared number of files in the CDE of an invalid zip when the number of
/// files declared is more than the alleged offset in the CDE
#[test]
fn invalid_cde_number_of_files_allocation_smaller_offset() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!(
"../tests/data/invalid_cde_number_of_files_allocation_smaller_offset.zip"
));
let reader = ZipArchive::new(io::Cursor::new(v));
assert!(reader.is_err());
}
/// test case to ensure we don't preemptively over allocate based on the
/// declared number of files in the CDE of an invalid zip when the number of
/// files declared is less than the alleged offset in the CDE
#[test]
fn invalid_cde_number_of_files_allocation_greater_offset() {
use super::ZipArchive;
use std::io;
let mut v = Vec::new();
v.extend_from_slice(include_bytes!(
"../tests/data/invalid_cde_number_of_files_allocation_greater_offset.zip"
));
let reader = ZipArchive::new(io::Cursor::new(v));
assert!(reader.is_err());
}
}