forked from loweel/zabov
105 lines
1.8 KiB
Go
105 lines
1.8 KiB
Go
package main
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/gob"
|
|
"fmt"
|
|
"time"
|
|
|
|
"github.com/miekg/dns"
|
|
)
|
|
|
|
|
|
|
|
type cacheItem struct {
|
|
Query []byte
|
|
Date time.Time
|
|
}
|
|
|
|
//DomainCache stores a domain name inside the cache
|
|
func DomainCache(s string, resp *dns.Msg) {
|
|
|
|
var domain2cache cacheItem
|
|
var err error
|
|
var dom2 bytes.Buffer
|
|
enc := gob.NewEncoder(&dom2)
|
|
|
|
domain2cache.Query, err = resp.Pack()
|
|
if err != nil {
|
|
fmt.Println("Problems packing the response: ", err.Error())
|
|
}
|
|
domain2cache.Date = time.Now()
|
|
|
|
err = enc.Encode(domain2cache)
|
|
|
|
if err != nil {
|
|
fmt.Println("Cannot GOB the domain to cache: ", err.Error())
|
|
}
|
|
|
|
cacheDomain(s, dom2.Bytes())
|
|
|
|
}
|
|
|
|
func cacheDomain(key string, domain []byte) {
|
|
|
|
err := MyZabovCDB.Put([]byte(key), domain, nil)
|
|
if err != nil {
|
|
fmt.Println("Cannot write to Cache DB: ", err.Error())
|
|
}
|
|
|
|
}
|
|
|
|
//GetDomainFromCache stores a domain name inside the cache
|
|
func GetDomainFromCache(s string) *dns.Msg {
|
|
|
|
ret := new(dns.Msg)
|
|
var cache bytes.Buffer
|
|
dec := gob.NewDecoder(&cache)
|
|
var record cacheItem
|
|
var conf []byte
|
|
var errDB error
|
|
|
|
if domainInCache(s) == false {
|
|
return nil
|
|
}
|
|
|
|
conf, errDB = MyZabovCDB.Get([]byte(s), nil)
|
|
if errDB != nil {
|
|
fmt.Println("Cant READ DB :" , errDB.Error() )
|
|
return nil
|
|
}
|
|
|
|
cache.Write(conf)
|
|
|
|
err := dec.Decode(&record)
|
|
if err != nil {
|
|
fmt.Println("Decode error :", err.Error())
|
|
return nil
|
|
}
|
|
|
|
if time.Since(record.Date) > (time.Duration(ZabovCacheTTL) * time.Hour) {
|
|
return nil
|
|
}
|
|
|
|
err = ret.Unpack(record.Query)
|
|
if err != nil {
|
|
fmt.Println("Problem unpacking response: ", err.Error())
|
|
return nil
|
|
}
|
|
|
|
return ret
|
|
|
|
}
|
|
|
|
func domainInCache(domain string) bool {
|
|
|
|
has, err := MyZabovCDB.Has([]byte(domain), nil)
|
|
if err != nil {
|
|
fmt.Println("Cannot search Cache DB: ", err.Error())
|
|
return false
|
|
}
|
|
|
|
return has
|
|
|
|
}
|