1
0
mirror of https://github.com/bingohuang/docker-labs.git synced 2025-07-16 03:07:26 +08:00
Marcos Nils 62c5d3761d Add support for setting stacks when creating session (#138)
* Add support for setting stacks when creating session

* Add exec endpoint and move dns stuff to another package

* Rename command and status code
2017-05-11 10:34:16 -03:00

94 lines
2.5 KiB
Go

package handlers
import (
"fmt"
"log"
"net"
"regexp"
"strings"
"github.com/miekg/dns"
)
var dnsFilter = regexp.MustCompile(`pwd[0-9]{1,3}_[0-9]{1,3}_[0-9]{1,3}_[0-9]{1,3}`)
func DnsRequest(w dns.ResponseWriter, r *dns.Msg) {
if len(r.Question) > 0 && dnsFilter.MatchString(r.Question[0].Name) {
// this is something we know about and we should try to handle
question := r.Question[0].Name
domainChunks := strings.Split(question, ".")
tldChunks := strings.Split(strings.TrimPrefix(domainChunks[0], "pwd"), "-")
ip := strings.Replace(tldChunks[0], "_", ".", -1)
m := new(dns.Msg)
m.SetReply(r)
m.Authoritative = true
m.RecursionAvailable = true
a, err := dns.NewRR(fmt.Sprintf("%s 60 IN A %s", question, ip))
if err != nil {
log.Fatal(err)
}
m.Answer = append(m.Answer, a)
w.WriteMsg(m)
return
} else {
if len(r.Question) > 0 {
question := r.Question[0].Name
if question == "localhost." {
log.Printf("Not a PWD host. Asked for [localhost.] returning automatically [127.0.0.1]\n")
m := new(dns.Msg)
m.SetReply(r)
m.Authoritative = true
m.RecursionAvailable = true
a, err := dns.NewRR(fmt.Sprintf("%s 60 IN A 127.0.0.1", question))
if err != nil {
log.Fatal(err)
}
m.Answer = append(m.Answer, a)
w.WriteMsg(m)
return
}
log.Printf("Not a PWD host. Looking up [%s]\n", question)
ips, err := net.LookupIP(question)
if err != nil {
// we have no information about this and we are not a recursive dns server, so we just fail so the client can fallback to the next dns server it has configured
w.Close()
// dns.HandleFailed(w, r)
return
}
log.Printf("Not a PWD host. Looking up [%s] got [%s]\n", question, ips)
m := new(dns.Msg)
m.SetReply(r)
m.Authoritative = true
m.RecursionAvailable = true
for _, ip := range ips {
ipv4 := ip.To4()
if ipv4 == nil {
a, err := dns.NewRR(fmt.Sprintf("%s 60 IN AAAA %s", question, ip.String()))
if err != nil {
log.Fatal(err)
}
m.Answer = append(m.Answer, a)
} else {
a, err := dns.NewRR(fmt.Sprintf("%s 60 IN A %s", question, ipv4.String()))
if err != nil {
log.Fatal(err)
}
m.Answer = append(m.Answer, a)
}
}
w.WriteMsg(m)
return
} else {
log.Printf("Not a PWD host. Got DNS without any question\n")
// we have no information about this and we are not a recursive dns server, so we just fail so the client can fallback to the next dns server it has configured
w.Close()
// dns.HandleFailed(w, r)
return
}
}
}