Interface Backend

platform/backend.go:24–41

Backend is implemented by per-OS packet interception providers. Semantics: - Open installs filter rules (iptables / WinDivert filter / pf) and prepares the userspace packet queue. - Close cleans up all side effects (removes rules, unloads drivers). - Packets returns a channel of observed packets in

//     the configured filter scope. Backends call Verdict on each delivered
//     packet exactly once.
type Backend interface {
	// Open installs the filter rules and starts packet interception. The
	// returned error indicates a fatal setup failure (missing driver,
	// insufficient privileges, rule conflict).
	Open(ctx context.Context, scope Scope) error

	// Packets returns the stream of intercepted packets. The channel is
	// closed when the backend is stopped.
	Packets() <-chan Packet

	// Inject emits a raw IP packet onto the wire, bypassing the filter.
	// Used to send the spoofed ClientHello.
	Inject(p []byte, dir Direction) error

	// Close tears down rules and stops interception. Safe to call multiple
	// times.
	Close() error
}

// Scope narrows packet interception to a specific 5-tuple family.
// Backends translate this into their native filter language.