94 lines
1.8 KiB
Go
94 lines
1.8 KiB
Go
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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)
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type Tendrils struct {
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activeInterfaces map[string]context.CancelFunc
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}
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func New() *Tendrils {
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return &Tendrils{
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activeInterfaces: map[string]context.CancelFunc{},
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}
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}
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func (t *Tendrils) Run() {
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ticker := time.NewTicker(1 * time.Second)
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defer ticker.Stop()
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for {
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interfaces := t.listInterfaces()
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t.updateInterfaces(interfaces)
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<-ticker.C
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}
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}
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func (t *Tendrils) listInterfaces() []net.Interface {
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interfaces, err := net.Interfaces()
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if err != nil {
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log.Printf("[ERROR] error getting interfaces: %v", err)
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return nil
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}
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var validInterfaces []net.Interface
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for _, iface := range interfaces {
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if iface.Flags&net.FlagUp == 0 {
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continue
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}
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if iface.Flags&net.FlagLoopback != 0 {
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continue
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}
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if iface.Flags&net.FlagPointToPoint != 0 {
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continue
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}
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if iface.Flags&net.FlagBroadcast == 0 {
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continue
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}
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if len(iface.HardwareAddr) == 0 {
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continue
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}
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addrs, err := iface.Addrs()
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if err != nil || len(addrs) == 0 {
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continue
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}
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validInterfaces = append(validInterfaces, iface)
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}
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return validInterfaces
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}
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func (t *Tendrils) updateInterfaces(interfaces []net.Interface) {
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current := map[string]bool{}
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for _, iface := range interfaces {
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current[iface.Name] = true
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}
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for name, cancel := range t.activeInterfaces {
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if !current[name] {
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log.Printf("interface removed: %s", name)
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cancel()
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delete(t.activeInterfaces, name)
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}
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}
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for _, iface := range interfaces {
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if _, exists := t.activeInterfaces[iface.Name]; !exists {
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log.Printf("interface added: %s", iface.Name)
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ctx, cancel := context.WithCancel(context.Background())
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t.activeInterfaces[iface.Name] = cancel
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t.startInterface(ctx, iface)
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}
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}
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}
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func (t *Tendrils) startInterface(ctx context.Context, iface net.Interface) {
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go t.listenLLDP(ctx, iface)
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}
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