AdGuardHome/internal/arpdb/arpdb_openbsd.go

64 lines
1.3 KiB
Go

//go:build openbsd
package arpdb
import (
"bufio"
"log/slog"
"strings"
"sync"
"github.com/AdguardTeam/golibs/logutil/slogutil"
)
func newARPDB(logger *slog.Logger) (arp *cmdARPDB) {
return &cmdARPDB{
logger: logger,
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(logger *slog.Logger, 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, err := newNeighbor("", fields[0], fields[1])
if err != nil {
logger.Debug("parsing arp output", "line", ln, slogutil.KeyError, err)
continue
}
ns = append(ns, *n)
}
return ns
}