95 lines
3.0 KiB
Go
95 lines
3.0 KiB
Go
|
/*
|
||
|
|
crondyn, a cron-compatible dynamic DNS update utility.
|
||
|
|
© 2014 Ken Piper <kealper@gmail.com>
|
||
|
|
|
||
|
|
This file is part of crondyn.
|
||
|
|
|
||
|
|
crondyn is free software: you can redistribute it and/or modify
|
||
|
|
it under the terms of the GNU General Public License as published by
|
||
|
|
the Free Software Foundation, either version 3 of the License, or
|
||
|
|
(at your option) any later version.
|
||
|
|
|
||
|
|
crondyn is distributed in the hope that it will be useful,
|
||
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
|
GNU General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU General Public License
|
||
|
|
along with crondyn. If not, see <http://www.gnu.org/licenses/>.
|
||
|
|
*/
|
||
|
|
|
||
|
|
package main
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"encoding/json"
|
||
|
|
"net/http"
|
||
|
|
"net/url"
|
||
|
|
"io/ioutil"
|
||
|
|
"runtime"
|
||
|
|
)
|
||
|
|
|
||
|
|
type Config struct {
|
||
|
|
Username string
|
||
|
|
Password string
|
||
|
|
Hostname string
|
||
|
|
DNSServer string
|
||
|
|
}
|
||
|
|
|
||
|
|
func shutDown() {
|
||
|
|
if panicReason := recover(); panicReason != nil {
|
||
|
|
fmt.Println("Program has encountered an unrecoverable error and has crashed.")
|
||
|
|
fmt.Println("Some information describing this crash: "+panicReason.(error).Error())
|
||
|
|
fmt.Println("Crash reporting is enabled, collecting stack trace and submitting crash report...")
|
||
|
|
stack := make([]byte, 8192)
|
||
|
|
l := runtime.Stack(stack, true)
|
||
|
|
resp, err := http.PostForm("http://stacktrace.kealper.com/api.a3w", url.Values{"agent": {"crondns/1.0"}, "crash": {panicReason.(error).Error()}, "stack": {string(stack[:l])}})
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println("Failed to submit crash report, closing.")
|
||
|
|
} else {
|
||
|
|
resp.Body.Close()
|
||
|
|
fmt.Println("Crash report submitted, closing.")
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func main() {
|
||
|
|
defer shutDown()
|
||
|
|
configFile, _ := ioutil.ReadFile("config.json")
|
||
|
|
config := new(Config)
|
||
|
|
err := json.Unmarshal(configFile, config)
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println("Failed to load configuration! Closing...")
|
||
|
|
return
|
||
|
|
}
|
||
|
|
lastIP, err := ioutil.ReadFile("lastip")
|
||
|
|
if err != nil {
|
||
|
|
lastIP = []byte("0.0.0.0")
|
||
|
|
}
|
||
|
|
resp, err := http.Get("http://"+config.DNSServer+"/checkip.php")
|
||
|
|
if err != nil {
|
||
|
|
resp, err = http.Get("http://kealper.com/ip")
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println("Failed to get current IP address! Closing...")
|
||
|
|
return
|
||
|
|
}
|
||
|
|
}
|
||
|
|
currentIP, _ := ioutil.ReadAll(resp.Body)
|
||
|
|
resp.Body.Close()
|
||
|
|
if string(currentIP) != string(lastIP) {
|
||
|
|
fmt.Println("Found updated IP address:", string(currentIP))
|
||
|
|
if err := ioutil.WriteFile("lastip", currentIP, 0644); err != nil {
|
||
|
|
fmt.Println("Failed to save the current IP to the disk! Permissions issue?")
|
||
|
|
}
|
||
|
|
_, err := http.Get("http://"+config.Username+":"+config.Password+"@"+config.DNSServer+"/dynamicupdate.php?ip="+string(currentIP)+"&hostname="+config.Hostname)
|
||
|
|
if err != nil {
|
||
|
|
fmt.Println("Failed to update hostname:", config.Hostname)
|
||
|
|
return
|
||
|
|
} else {
|
||
|
|
fmt.Println("Hostname", config.Hostname, "updated successfully.")
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
fmt.Println("No IP address change since last check.")
|
||
|
|
}
|
||
|
|
}
|