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>
- Closes#51. Again.
- No real notable API changes. The largest change code-wise is in
Vminitd. The connection loop is set up immediately in the new API by
calling runConnections() on the client, and this blocks until either the
task it's running on is cancelled or beginGracefulShutdown is called.
Because of this, either we'd have to modify our API to have
VirtualMachineAgent implementations call some run() method, or we just
put runConnections in an internal task on Vminitd. This change uses the
latter approach as it's simpler.
- Updated dependencies to pick up latest protobuf and grpc-swift-2
fixes.
- ClientBootstrap.withConnectedSocket(fd).wait() registers the vsock fd
with epoll/kqueue immediately. vminitd sends its HTTP/2 SETTINGS frame
right away upon accepting the connection, so those bytes can arrive on
the fd — and be read by NIO — before the gRPC pipeline is installed.
With a bare pipeline, NIO has nowhere to send the bytes and discards
them.
- Buffer until ClientConnectionHandler is in the pipeline so it can
process the SETTINGS frame and fire .ready, then schedule delivery of
the buffered data with assumeIsolatedUnsafeUnchecked().execute.
- To help produce more accurate merged logs, defines a
`StderrLogHandler` in the vminitd Application.swift that writes
timestamps to the boot log with millisecond precision and format
identical to that of the log files created using the `--log-root` arg on
`container`.
- Updates hawkeye to latest version (v6.5.1).
- In vminitd, use the Server event loop group for the gRPC server.
Co-authored-by: Danny Canter <danny_canter@apple.com>
- No real notable API changes. The largest change code-wise is in
Vminitd. The connection loop is set up immediately in the new API by
calling runConnections() on the client, and this blocks until either the
task it's running on is cancelled or beginGracefulShutdown is called.
Because of this, either we'd have to modify our API to have
VirtualMachineAgent implementations call some run() method, or we just
put runConnections in an internal task on Vminitd. This change uses the
latter approach as it's simpler.
- Updated dependencies to pick up latest protobuf and grpc-swift-2
fixes.
- ClientBootstrap.withConnectedSocket(fd).wait() registers the vsock fd
with epoll/kqueue immediately. vminitd sends its HTTP/2 SETTINGS frame
right away upon accepting the connection, so those bytes can arrive on
the fd — and be read by NIO — before the gRPC pipeline is installed.
With a bare pipeline, NIO has nowhere to send the bytes and discards
them.
- Buffer until ClientConnectionHandler is in the pipeline so it can
process the SETTINGS frame and fire .ready, then schedule delivery of
the buffered data with assumeIsolatedUnsafeUnchecked().execute.
- To help produce more accurate merged logs, defines a
`StderrLogHandler` in the vminitd Application.swift that writes
timestamps to the boot log with millisecond precision and format
identical to that of the log files created using the `--log-root` arg on
`container`.
- Updates hawkeye to latest version (v6.5.1).
---------
Co-authored-by: Danny Canter <danny_canter@apple.com>
Aditya Ramani