- Closes#532.
- Relocate all zstd calls down into CArchive, and export a function
zstd_decompress_fd(src_fd, dst_fd) that ContainerizationArchive can use.
This eliminates problems that can occur when treating Swift warnings as
errors in Xcode projects that use ContainerizationArchive.
- InputSource(url:) rejects URLs with nil scheme, which was what was
passed when running the `container system kernel set` integration test
with a local kernel archive path.
- Closesapple/container#988.
- macOS libarchive is not built with zstd support, so the workaround in
ArchiveReader is to attempt to decompress every archive as zstd. If
decompression fails, we pass the original archive to libarchive. If it
succeeds, we pass the uncompressed archive.
- Adds blob media type recognition for zstd to EXT4Unpacker. Tested zstd
blob unpack using `image pull tonistiigi/hello-world:zstd-docker`.
Co-authored-by: Aditya Ramani <a_ramani@apple.com>
* Admit only valid OCI layout files when loading image.
- Adds `AdmissionMapper` protocol for validating archive
member paths and normalizing them to relative paths
under the extraction root directory.
- Renames `Reader.swift` to `ArchiveReader.swift` to
match type name.
- Rework `TempDir` to address `NSString.utf8String`
deprecation warning in Swift 6.2.3.
- Rework `ArchiveReader.extractContent()` to use an
`AdmissionMapper` to validate and remap archive
members before extracting.
- Adds `IdentityAdmissionWrapper` for naive extraction.
- Adds `NoSymlinkAdmissionWrapper` that only extracts
regular files and directories under the extraction root.
- Adds `OCIImageAdmissionWrapper` that only extracts
valid OCI image layout paths.
- Use `OCIImageAdmissionWrapper` for `cctl image load`
and print rejected paths.
* PR feedback.
* Adds public init() for TrustedAdmissionMapper.
* Replace AdmissionMapper with more secure extraction.
- Adds FileDescriptor.mkdirSecure() to prevent
root escapes on member pathnames, and to prevent
symlink traversal.
- Adds FileDescriptor.unlinkRecursive() to
facilitate overwrites when there are multiple
archive entries with the same member path.
- Adds FileDescriptor.validateSymlinkTargetInRoot()
to validate that extracted symlink targets do
not escape the root.
- Rewrite ArchiveReader.extractContents() to use
secure path functions.
* Remove unneeded symlink check, rename files.
* Simplify the lexical normalizer workaround.
* Reject member paths containing parent traversal components.
* Remove unused lexical normalization workaround.
* Fix leaking fds, extract absolute members as relative.
Optimize unpack a little by trying to reduce allocations in the hot
path. Today for every file we read the entire file into memory and then
pass the data blob to the ext4 writer to eventually be written to the
sparse file. Before being written to the sparse file the data is copied
*again* to a temp buffer before finally hitting write(2) in FileHandle.
This change moves things around such that we can pass an optional buffer
to the ext4 create() (so we can reuse a buffer for file writes), as well
as stops reading entire files into memory by passing the archive entry
itself (wrapped in a ReaderStream object albeit) down to the writer.
Testing with unpacking every platform for
`docker.io/jenkins/jenkins:lts` on an M1 Max:
Old Avg (5 runs): 7.43s
New Avg (5 runs): 5.31s
Continue the allocations journey for anything that is in the codepaths
for pulling images. This time there's a couple spots in archive and ext4
we can get rid of some copies.
J Logan