zabov/dns_handler.go

125 lines
3.1 KiB
Go

package main
import (
"fmt"
"net"
"strings"
"time"
"github.com/miekg/dns"
)
var weekdays []string
func init() {
weekdays = []string{"Su", "Mo", "Tu", "We", "Th", "Fr", "Sa"}
}
func getCurTime() (time.Time, error) {
return time.Parse("15:04", time.Now().Format("15:04"))
}
func confFromTimeTable(timetable string) string {
tt := ZabovTimetables[timetable]
if tt == nil {
fmt.Println("confFromTimeTable: return default")
return "default"
}
for _, ttentry := range tt.table {
now := time.Now()
nowHour := now.Hour()
nowMinute := now.Minute()
weekday := weekdays[now.Weekday()]
if ttentry.days == nil || len(ttentry.days) == 0 || ttentry.days[weekday] || ttentry.days[strings.ToLower(weekday)] {
for _, t := range ttentry.times {
if (nowHour > t.start.hour || (nowHour == t.start.hour && nowMinute >= t.start.minute)) &&
(nowHour < t.stop.hour || (nowHour == t.stop.hour && nowMinute <= t.stop.minute)) {
go incrementStats("TIMETABLE IN: "+timetable, 1)
fmt.Println("confFromTimeTable: return IN", tt.cfgin)
return tt.cfgin
}
}
}
}
go incrementStats("TIMETABLE OUT: "+timetable, 1)
fmt.Println("confFromTimeTable: return OUT", tt.cfgout)
return tt.cfgout
}
func confFromIP(clientIP net.IP) string {
for _, ipgroup := range ZabovIPGroups {
for _, ip := range ipgroup.ips {
if clientIP.Equal(ip) {
if len(ipgroup.timetable) > 0 {
return confFromTimeTable(ipgroup.timetable)
}
fmt.Println("confFromIP: ipgroup.cfg")
return ipgroup.cfg
}
}
}
fmt.Println("confFromIP: return default")
return "default"
}
func (mydns *handler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
go incrementStats("TotalQueries", 1)
remIP, _, e := net.SplitHostPort(w.RemoteAddr().String())
if e != nil {
go incrementStats("CLIENT ERROR: "+remIP, 1)
} else {
go incrementStats("CLIENT: "+remIP, 1)
}
msg := dns.Msg{}
msg.SetReply(r)
config := confFromIP(net.ParseIP(remIP))
ZabovConfig := ZabovConfigs[config]
switch r.Question[0].Qtype {
case dns.TypeA:
msg.Authoritative = true
domain := msg.Question[0].Name
fqdn := strings.TrimRight(domain, ".")
if len(ZabovIPAliases[fqdn]) > 0 {
config = "__aliases__"
msg.Answer = append(msg.Answer, &dns.A{
Hdr: dns.RR_Header{Name: domain, Rrtype: dns.TypeA, Class: dns.ClassINET, Ttl: 60},
A: net.ParseIP(ZabovIPAliases[fqdn]),
})
break
}
if len(ZabovLocalResponder) > 0 {
if !strings.Contains(fqdn, ".") ||
(len(ZabovLocalDomain) > 0 && strings.HasSuffix(fqdn, ZabovLocalDomain)) {
config = "__localresponder__"
ret := ForwardQuery(r, config, true)
w.WriteMsg(ret)
break
}
}
if domainInKillfile(fqdn, config) {
go incrementStats("Killed", 1)
msg.Answer = append(msg.Answer, &dns.A{
Hdr: dns.RR_Header{Name: domain, Rrtype: dns.TypeA, Class: dns.ClassINET, Ttl: 60},
A: net.ParseIP(ZabovConfig.ZabovAddBL),
})
} else {
ret := ForwardQuery(r, config, false)
w.WriteMsg(ret)
}
default:
ret := ForwardQuery(r, config, false)
w.WriteMsg(ret)
}
go incrementStats("CONFIG: "+config, 1)
w.WriteMsg(&msg)
}