sing-box/common/sniff/dtls.go
2024-08-20 21:10:05 +08:00

33 lines
656 B
Go

package sniff
import (
"context"
"os"
"github.com/sagernet/sing-box/adapter"
C "github.com/sagernet/sing-box/constant"
)
func DTLSRecord(ctx context.Context, metadata *adapter.InboundContext, packet []byte) error {
const fixedHeaderSize = 13
if len(packet) < fixedHeaderSize {
return os.ErrInvalid
}
contentType := packet[0]
switch contentType {
case 20, 21, 22, 23, 25:
default:
return os.ErrInvalid
}
versionMajor := packet[1]
if versionMajor != 0xfe {
return os.ErrInvalid
}
versionMinor := packet[2]
if versionMinor != 0xff && versionMinor != 0xfd {
return os.ErrInvalid
}
metadata.Protocol = C.ProtocolDTLS
return nil
}