badguardhome/internal/aghnet/arpdb_bsd.go
Eugene Burkov 12ee287d0b Pull request: 3157 excessive ptrs
Merge in DNS/adguard-home from 3157-excessive-ptrs to master

Updates #3157.

Squashed commit of the following:

commit 6803988240dca2f147bb80a5b3f78d7749d2fa14
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 19 14:50:01 2022 +0300

    aghnet: and again

commit 1a7f4d1dbc8fd4d3ae620349917526a75fa71b47
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 19 14:49:20 2022 +0300

    aghnet: docs again

commit d88da1fc7135f3cd03aff10b02d9957c8ffdfd30
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 19 14:47:36 2022 +0300

    aghnet: imp docs

commit c45dbc7800e882c6c4110aab640c32b03046f89a
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 19 14:41:19 2022 +0300

    aghnet: keep alphabetical order

commit b61781785d096ef43f60fb4f1905a4ed3cdf7c68
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 19 13:50:56 2022 +0300

    aghnet: imp code quality

commit 578dbd71ed2f2089c69343d7d4bf8bbc29150ace
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue Apr 12 17:02:38 2022 +0300

    aghnet: imp arp container
2022-04-19 15:01:49 +03:00

77 lines
1.5 KiB
Go

//go:build darwin || freebsd
// +build darwin freebsd
package aghnet
import (
"bufio"
"net"
"strings"
"sync"
"github.com/AdguardTeam/golibs/log"
"github.com/AdguardTeam/golibs/netutil"
)
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 macOS and FreeBSD.
// The expected input format:
//
// host.name (192.168.0.1) at ff:ff:ff:ff:ff:ff on en0 ifscope [ethernet]
//
func parseArpA(sc *bufio.Scanner, lenHint int) (ns []Neighbor) {
ns = make([]Neighbor, 0, lenHint)
for sc.Scan() {
ln := sc.Text()
fields := strings.Fields(ln)
if len(fields) < 4 {
continue
}
n := Neighbor{}
if ipStr := fields[1]; len(ipStr) < 2 {
continue
} else if ip := net.ParseIP(ipStr[1 : len(ipStr)-1]); ip == nil {
continue
} else {
n.IP = ip
}
hwStr := fields[3]
if mac, err := net.ParseMAC(hwStr); err != nil {
continue
} else {
n.MAC = mac
}
host := fields[0]
if err := netutil.ValidateDomainName(host); err != nil {
log.Debug("parsing arp output: %s", err)
} else {
n.Name = host
}
ns = append(ns, n)
}
return ns
}