OpenGFW/io/interface.go

60 lines
1.8 KiB
Go

package io
import (
"context"
"net"
"time"
)
type Verdict int
const (
// VerdictAccept accepts the packet, but continues to process the stream.
VerdictAccept Verdict = iota
// VerdictAcceptModify is like VerdictAccept, but replaces the packet with a new one.
VerdictAcceptModify
// VerdictAcceptStream accepts the packet and stops processing the stream.
VerdictAcceptStream
// VerdictDrop drops the packet, but does not block the stream.
VerdictDrop
// VerdictDropStream drops the packet and blocks the stream.
VerdictDropStream
)
// Packet represents an IP packet.
type Packet interface {
// StreamID is the ID of the stream the packet belongs to.
StreamID() uint32
// Timestamp is the time the packet was received.
Timestamp() time.Time
// Data is the raw packet data, starting with the IP header.
Data() []byte
}
// PacketCallback is called for each packet received.
// Return false to "unregister" and stop receiving packets.
type PacketCallback func(Packet, error) bool
type PacketIO interface {
// Register registers a callback to be called for each packet received.
// The callback should be called in one or more separate goroutines,
// and stop when the context is cancelled.
Register(context.Context, PacketCallback) error
// SetVerdict sets the verdict for a packet.
SetVerdict(Packet, Verdict, []byte) error
// ProtectedDialContext is like net.DialContext, but the connection is "protected"
// in the sense that the packets sent/received through the connection must bypass
// the packet IO and not be processed by the callback.
ProtectedDialContext(ctx context.Context, network, address string) (net.Conn, error)
// Close closes the packet IO.
Close() error
}
type ErrInvalidPacket struct {
Err error
}
func (e *ErrInvalidPacket) Error() string {
return "invalid packet: " + e.Err.Error()
}