apple/containerization currently runs containers in per-container VMs on
macOS hosts via Virtualization.framework. This adds a second VMM backend
so the same Swift orchestration layer (LinuxContainer / LinuxPod /
Vminitd gRPC contract) runs on Linux hosts via cloud-hypervisor + KVM.
**CloudHypervisor Swift package** (`Sources/CloudHypervisor/`) — a thin
client for cloud-hypervisor's REST-over-UDS API, layered on
AsyncHTTPClient. Endpoints cover VMM / VM lifecycle / hotplug (disk, fs,
net, vsock, remove-device). Cross-platform (compiles on macOS for unit
tests; consumed at runtime only by the Linux side of Containerization).
**CH backend in Containerization** — one cloud-hypervisor subprocess per
VM, gated behind `#if os(Linux)`. CHVirtualMachineManager /
CHVirtualMachineInstance mirror the VZ shape behind the existing
VirtualMachineManager / VirtualMachineInstance protocol. CHProcess and
VirtiofsdProcess manage the binaries; CHHotplugProvider handles
virtio-blk and virtio-fs runtime hotplug (with one virtiofsd per unique
source-hash tag, refcounted across containers).
**Linux host networking** — BridgeManager brings up a Linux bridge with
an IPv4 subnet and (opt-in via `--enable-nat`) iptables MASQUERADE +
scoped FORWARD rules. LinuxBridgedNetwork enslaves a fresh TAP per
container to the bridge. State is recorded under `/run/containerization`
so `cctl bridge delete` reverses exactly what create did. Bridge
teardown verifies the link kind via sysfs to refuse deleting non-bridge
interfaces.
**cctl run / bridge** — end-to-end Linux container run path (image pull,
ext4 rootfs assembly, VM boot, container exec) plus `cctl bridge
create|delete` for the host network plumbing.
**Build & dist** — `make linux-build` / `make linux-integration` build
and exercise the host side inside an apple/container `--virtualization`
dev container. `make dist-x86_64` produces a deployment tarball (cctl +
cloud-hypervisor + virtiofsd + initfs + kernel) cross-compiled from the
aarch64 dev container; pipeline documented in `docs/x86_64-build.md`.
Static-musl C deps and the Zig cross compiler are pinned by SHA256.
The host orchestrator runs as root. Per-VM runtime state lives under
`/run/containerization/ch/<UUID>` with mode 0700; UDS sockets inside are
bound with mode 0600. Vminitd's gRPC channel inherits that trust
boundary — socket-file perms are the auth.
Sandbox flags are upstream-secure by default. Two per-component opt-outs
exist for the apple/container dev-container case (where the host seccomp
profile SIGSYS-kills CH and virtiofsd):
- `CONTAINERIZATION_NO_CH_SECCOMP=1` — `cloud-hypervisor --seccomp
false`.
- `CONTAINERIZATION_NO_VIRTIOFSD_SANDBOX=1` — `virtiofsd --sandbox
none`. Each emits a one-shot `logger.warning` at process start. Legacy
alias `CONTAINERIZATION_RELAXED_SANDBOX=1` flips both. cctl spawns both
binaries with `setsid` and a minimal env allowlist (PATH / HOME /
RUST_LOG / RUST_BACKTRACE) so the parent's secrets don't leak to
children.
`make linux-integration` runs the cross-platform integration suite
against a real cloud-hypervisor VM inside the dev container. Linux runs
the cross-platform subset (`process true`/`false`/`echo hi`, virtiofs
round-trip, hotplug); the macOS suite is unchanged.
Signed-off-by: michael_crosby <michael_crosby@apple.com>
To be able to test vminitd/vmexec/linux specific packages on ci it'd be
a heck of a lot easier if `make` just worked. This should be the last
bit needed. The default goal currently compiles just fine after the
linux specific `make deps` is ran. Next in line would be adding decent
unit tests/actually getting ci setup for the linux bits.
- Add a `list` function that is needed for the `container registry list`
command
- Updates to `KeychainHelper` and `KeychainQuery` variable/parameter
names
- Updates to test cases
* 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
Creates a new Unpacker protocol that defines a single method
```
func unpack(_ image: Image, for platform: Platform, at path: URL, progress: ProgressHandler?) async throws -> Mount
```
This change also removes the `unpack(...)` method from the Image type.
Before
```
let mount = try await image.unpack(for: platform, at: path)
```
After
```
let unpacker = EXT4Unpacker(blockSizeInBytes: 2.gib())
let mount = try await unpacker.unpack(image, for: platform, at: path)
```
---------
Signed-off-by: Aditya Ramani <a_ramani@apple.com>
Michael Crosby