karasz/gip
1
Fork 0
Code Issues Pull Requests Releases 3 Wiki Activity

gip: add google and modify structure

Browse Source 
Signed-off-by: Nagy Károly Gábriel <k@jpi.io>
This commit is contained in:
Nagy Károly Gábriel
2019-01-19 13:01:29 +02:00
parent d8c63763fd
commit cf79e2e8f0
1 changed files with 86 additions and 42 deletions
Download Patch File Download Diff File Expand all files Collapse all files
gip.go
+86 -42
View File
@@ -2,8 +2,8 @@ package main
import (
"fmt"
"github.com/miekg/dns"
"os"
)
/*
@@ -11,58 +11,102 @@ dig {-4,-6} +short myip.opendns.com @resolver1.opendns.com
dig {-4,-6} TXT +short o-o.myaddr.l.google.com @ns1.google.com
*/
func get4(c *dns.Client, m *dns.Msg, nameserver string) (*dns.Msg, error) {
c.Net = "udp4"
m.SetQuestion("myip.opendns.com.", dns.TypeA)
r, _, err := c.Exchange(m, nameserver)
return r, err
}
func get6(c *dns.Client, m *dns.Msg, nameserver string) (*dns.Msg, error) {
c.Net = "udp6"
m.SetQuestion("myip.opendns.com.", dns.TypeAAAA)
r, _, err := c.Exchange(m, nameserver)
return r, err
}
func printIP(ra []dns.RR) []string {
var ips []string
for _, ansa := range ra {
switch ansb := ansa.(type) {
case *dns.A:
ips = append(ips, ansb.A.String())
case *dns.AAAA:
ips = append(ips, ansb.AAAA.String())
}
}
return ips
}
func main() {
func getO() (ipv4 string, ipv6 string) {
nameserver := dns.Fqdn("resolver1.opendns.com") + ":53"
c := new(dns.Client)
c.Net = "udp4"
m := &dns.Msg{
MsgHdr: dns.MsgHdr{
RecursionDesired: true,
},
Question: make([]dns.Question, 1),
}
r4, err := get4(c, m, nameserver)
if err != nil {
fmt.Println(err)
// get IPv4 first
c.Net = "udp4"
m.SetQuestion("myip.opendns.com.", dns.TypeA)
r4, _, e4 := c.Exchange(m, nameserver)
if e4 != nil {
ipv4 = ""
} else {
fmt.Println(printIP(r4.Answer))
ipv4 = getIP(r4.Answer)
}
r6, e6 := get6(c, m, nameserver)
if err != nil {
fmt.Println(e6)
// now IPv6
c.Net = "udp6"
m.SetQuestion("myip.opendns.com.", dns.TypeAAAA)
r6, _, e6 := c.Exchange(m, nameserver)
if e6 != nil {
ipv6 = ""
} else {
fmt.Println(printIP(r6.Answer))
ipv6 = getIP(r6.Answer)
}
return ipv4, ipv6
}
func getG() (ipv4 string, ipv6 string) {
nameserver := dns.Fqdn("ns1.google.com") + ":53"
c := new(dns.Client)
m := &dns.Msg{
MsgHdr: dns.MsgHdr{
RecursionDesired: true,
},
Question: make([]dns.Question, 1),
}
// get IPv4 first
c.Net = "udp4"
m.SetQuestion("o-o.myaddr.l.google.com.", dns.TypeTXT)
r4, _, e4 := c.Exchange(m, nameserver)
if e4 != nil {
ipv4 = ""
} else {
ipv4 = getIP(r4.Answer)
}
// now IPv6
c.Net = "udp6"
m.SetQuestion("o-o.myaddr.l.google.com.", dns.TypeTXT)
r6, _, e6 := c.Exchange(m, nameserver)
if e6 != nil {
ipv6 = ""
} else {
ipv6 = getIP(r6.Answer)
}
return ipv4, ipv6
}
func getIP(ra []dns.RR) string {
//the answer will always be one IP or none
var ip string
for _, ansa := range ra {
switch ansb := ansa.(type) {
case *dns.A:
ip = ansb.A.String()
case *dns.AAAA:
ip = ansb.AAAA.String()
case *dns.TXT:
// we always expect only one IP in the field
ip = ansb.Txt[0]
}
}
return ip
}
func main() {
var ipv4, ipv6 string
exit := 0
o4, o6 := getO()
g4, g6 := getG()
if o4 == g4 {
ipv4 = o4
} else {
ipv4 = ""
exit = 111
}
if o6 == g6 {
ipv6 = o6
} else {
ipv6 = ""
exit = 111
}
fmt.Printf("%s\t%s\n", ipv4, ipv6)
os.Exit(exit)
}