//go:build openbsd package aghnet import ( "bufio" "net" "strings" "sync" "github.com/AdguardTeam/golibs/log" ) func newARPDB() (arp *cmdARPDB) { return &cmdARPDB{ parse: parseArpA, ns: &neighs{ mu: &sync.RWMutex{}, ns: make([]Neighbor, 0), }, cmd: "arp", // Use -n flag to avoid resolving the hostnames of the neighbors. By // default ARP attempts to resolve the hostnames via DNS. See man 8 // arp. // // See also https://github.com/AdguardTeam/AdGuardHome/issues/3157. args: []string{"-a", "-n"}, } } // parseArpA parses the output of the "arp -a -n" command on OpenBSD. The // expected input format: // // Host Ethernet Address Netif Expire Flags // 192.168.1.1 ab:cd:ef:ab:cd:ef em0 19m59s func parseArpA(sc *bufio.Scanner, lenHint int) (ns []Neighbor) { // Skip the header. if !sc.Scan() { return nil } ns = make([]Neighbor, 0, lenHint) for sc.Scan() { ln := sc.Text() fields := strings.Fields(ln) if len(fields) < 2 { continue } n := Neighbor{} if ip := net.ParseIP(fields[0]); ip == nil { continue } else { n.IP = ip } if mac, err := net.ParseMAC(fields[1]); err != nil { log.Debug("parsing arp output: %s", err) continue } else { n.MAC = mac } ns = append(ns, n) } return ns }