mirror of https://github.com/k3s-io/k3s
39 lines
853 B
Go
39 lines
853 B
Go
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package arping
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import (
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"net"
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"syscall"
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"time"
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)
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var sock int
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var toSockaddr syscall.SockaddrLinklayer
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func initialize(iface net.Interface) error {
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toSockaddr = syscall.SockaddrLinklayer{Ifindex: iface.Index}
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// 1544 = htons(ETH_P_ARP)
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const proto = 1544
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var err error
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sock, err = syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, proto)
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return err
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}
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func send(request arpDatagram) (time.Time, error) {
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return time.Now(), syscall.Sendto(sock, request.MarshalWithEthernetHeader(), 0, &toSockaddr)
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}
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func receive() (arpDatagram, time.Time, error) {
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buffer := make([]byte, 128)
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n, _, err := syscall.Recvfrom(sock, buffer, 0)
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if err != nil {
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return arpDatagram{}, time.Now(), err
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}
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// skip 14 bytes ethernet header
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return parseArpDatagram(buffer[14:n]), time.Now(), nil
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}
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func deinitialize() error {
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return syscall.Close(sock)
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}
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