Polite_realism
64c5bcdc46
The core, server, and sandbox-backend build scripts always used the vendored protoc binary and ignored PROTOC, so a distro build could not use its system compiler. When PROTOC is set, use it and let prost resolve the includes (PROTOC_INCLUDE still applies); otherwise behave exactly as before. Contributes to #3510. Signed-off-by: politerealism <burdcat17@gmail.com>
OpenShell sandbox backend
This crate implements the supervisor-side isolation backend and the private
control protocol shared with openshell-sandbox.
Exec recovery
An exec envelope carries a UUID request ID and an absolute expiration time in Unix milliseconds, set to 30 seconds after creation. The payload digest includes the expiration time, and transport recovery preserves the entire envelope. The supervisor and sandbox need synchronized wall clocks.
The sandbox checks expiration before starting or reattaching an exec. It keeps each admitted request ID until that deadline, independently of process and I/O retention. An expired request, including a delayed first attempt, is rejected even after its ID has been discarded. The sandbox never moves its observed admission clock backwards, so a clock adjustment cannot resurrect discarded requests. Expired IDs are reclaimed when the next exec request arrives.
There is no lifetime exec request count limit. The existing concurrent process retention limit still applies. The deadline governs admission and recovery; it does not terminate an already running command. A recovery timeout can leave the execution outcome unknown.
Exec envelopes without an expiration time are rejected. Update the supervisor and sandbox runtime together when deploying this protocol change.
Boundary audit validation
OpenShellRuntimeBackend implements the authenticated host side of the shared
Sandbox Protocol.
Backend implementations may inject a BoundaryAuditValidator to interpret
their opaque confirmation evidence. The default Linux validator rejects
incomplete or foreign evidence. Confirmation compares the asserted properties
with the properties derived by the selected validator; validator injection does
not bypass generation, session, resource, identity, or outer-fence checks.
Concrete platform validators belong to the implementing backend, not this shared transport library.
Boundary transport establishment
Backends may supply a BoundaryTransportConnector for raw stream establishment.
The shared client retains TLS peer verification, session bearer authentication,
generation checks, and reconnection handling. The connector is reused for policy
discovery and attachment; it does not define platform launch configuration or
replace the isolation interface.