70 lines
1.3 KiB
Go
70 lines
1.3 KiB
Go
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package tendrils
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import (
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"context"
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"log"
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"net"
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"time"
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"golang.org/x/net/icmp"
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"golang.org/x/net/ipv4"
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)
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func (t *Tendrils) pingBroadcast(ctx context.Context, iface net.Interface) {
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_, broadcast := getInterfaceIPv4(iface)
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if broadcast == nil {
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return
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}
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t.sendBroadcastPing(broadcast, iface.Name)
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ticker := time.NewTicker(30 * time.Second)
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defer ticker.Stop()
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for {
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select {
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case <-ctx.Done():
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return
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case <-ticker.C:
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t.sendBroadcastPing(broadcast, iface.Name)
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}
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}
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}
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func (t *Tendrils) sendBroadcastPing(broadcast net.IP, ifaceName string) {
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conn, err := icmp.ListenPacket("ip4:icmp", "0.0.0.0")
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if err != nil {
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if t.DebugARP {
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log.Printf("[broadcast] %s: failed to create icmp socket: %v", ifaceName, err)
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}
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return
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}
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defer conn.Close()
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msg := icmp.Message{
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Type: ipv4.ICMPTypeEcho,
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Code: 0,
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Body: &icmp.Echo{
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ID: 1,
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Seq: 1,
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Data: []byte("tendrils"),
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},
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}
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msgBytes, err := msg.Marshal(nil)
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if err != nil {
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return
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}
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_, err = conn.WriteTo(msgBytes, &net.IPAddr{IP: broadcast})
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if err != nil {
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if t.DebugARP {
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log.Printf("[broadcast] %s: failed to send ping to %s: %v", ifaceName, broadcast, err)
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}
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return
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}
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if t.DebugARP {
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log.Printf("[broadcast] %s: sent ping to %s", ifaceName, broadcast)
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}
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}
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