Files
tun2socks/filter/icmp.go
2019-08-14 23:15:49 +08:00

33 lines
620 B
Go

package filter
import (
"io"
"github.com/xjasonlyu/tun2socks/common/packet"
"github.com/xjasonlyu/tun2socks/log"
)
type icmpFilter struct {
writer io.Writer
}
func NewICMPFilter(w io.Writer) Filter {
return &icmpFilter{writer: w}
}
func (f *icmpFilter) Write(buf []byte) (int, error) {
switch buf[9] {
case packet.PROTOCOL_ICMP:
payload := make([]byte, len(buf))
copy(payload, buf)
go func(data []byte) {
if _, err := f.writer.Write(data); err != nil {
log.Fatalf("failed to input data to the stack: %v", err)
}
}(payload)
return len(buf), nil
default:
return f.writer.Write(buf)
}
}