VictoriaMetrics/vendor/github.com/prometheus/procfs/arp.go
Aliaksandr Valialkin d5c180e680 app/vmctl: move vmctl code from github.com/VictoriaMetrics/vmctl
It is better developing vmctl tool in VictoriaMetrics repository, so it could be released
together with the rest of vmutils tools such as vmalert, vmagent, vmbackup, vmrestore and vmauth.
2021-02-01 01:10:20 +02:00

85 lines
2.2 KiB
Go

// Copyright 2019 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package procfs
import (
"fmt"
"io/ioutil"
"net"
"strings"
)
// ARPEntry contains a single row of the columnar data represented in
// /proc/net/arp.
type ARPEntry struct {
// IP address
IPAddr net.IP
// MAC address
HWAddr net.HardwareAddr
// Name of the device
Device string
}
// GatherARPEntries retrieves all the ARP entries, parse the relevant columns,
// and then return a slice of ARPEntry's.
func (fs FS) GatherARPEntries() ([]ARPEntry, error) {
data, err := ioutil.ReadFile(fs.proc.Path("net/arp"))
if err != nil {
return nil, fmt.Errorf("error reading arp %s: %s", fs.proc.Path("net/arp"), err)
}
return parseARPEntries(data)
}
func parseARPEntries(data []byte) ([]ARPEntry, error) {
lines := strings.Split(string(data), "\n")
entries := make([]ARPEntry, 0)
var err error
const (
expectedDataWidth = 6
expectedHeaderWidth = 9
)
for _, line := range lines {
columns := strings.Fields(line)
width := len(columns)
if width == expectedHeaderWidth || width == 0 {
continue
} else if width == expectedDataWidth {
entry, err := parseARPEntry(columns)
if err != nil {
return []ARPEntry{}, fmt.Errorf("failed to parse ARP entry: %s", err)
}
entries = append(entries, entry)
} else {
return []ARPEntry{}, fmt.Errorf("%d columns were detected, but %d were expected", width, expectedDataWidth)
}
}
return entries, err
}
func parseARPEntry(columns []string) (ARPEntry, error) {
ip := net.ParseIP(columns[0])
mac := net.HardwareAddr(columns[3])
entry := ARPEntry{
IPAddr: ip,
HWAddr: mac,
Device: columns[5],
}
return entry, nil
}