From 2449075bca9e12bf052a2d217e05a9196817d5bd Mon Sep 17 00:00:00 2001
From: Eugene Bujak <hmage@hmage.net>
Date: Fri, 2 Nov 2018 12:15:30 +0300
Subject: [PATCH] Revert "Cache DNS lookups when resolving safebrowsing or
parental servers, also cache replacement hostnames as well."
This reverts commit a5d105352057bf24a59a08a2695f1d48f033cb17.
This cache had unintended side effects.
---
coredns_plugin/coredns_plugin.go | 45 +++++++++-----------------------
dnsfilter/dnsfilter.go | 1 -
2 files changed, 13 insertions(+), 33 deletions(-)
diff --git a/coredns_plugin/coredns_plugin.go b/coredns_plugin/coredns_plugin.go
index 5209e37b..f937cb84 100644
--- a/coredns_plugin/coredns_plugin.go
+++ b/coredns_plugin/coredns_plugin.go
@@ -41,16 +41,6 @@ func init() {
})
}
-type cacheEntry struct {
- answer []dns.RR
- lastUpdated time.Time
-}
-
-var (
- lookupCacheTime = time.Minute * 30
- lookupCache = map[string]cacheEntry{}
-)
-
type plugFilter struct {
ID int64
Path string
@@ -345,29 +335,20 @@ func (p *plug) replaceHostWithValAndReply(ctx context.Context, w dns.ResponseWri
records = append(records, result)
} else {
// this is a domain name, need to look it up
- cacheentry := lookupCache[val]
- if time.Since(cacheentry.lastUpdated) > lookupCacheTime {
- req := new(dns.Msg)
- req.SetQuestion(dns.Fqdn(val), question.Qtype)
- req.RecursionDesired = true
- reqstate := request.Request{W: w, Req: req, Context: ctx}
- result, err := p.upstream.Lookup(reqstate, dns.Fqdn(val), reqstate.QType())
- if err != nil {
- log.Printf("Got error %s\n", err)
- return dns.RcodeServerFailure, fmt.Errorf("plugin/dnsfilter: %s", err)
+ req := new(dns.Msg)
+ req.SetQuestion(dns.Fqdn(val), question.Qtype)
+ req.RecursionDesired = true
+ reqstate := request.Request{W: w, Req: req, Context: ctx}
+ result, err := p.upstream.Lookup(reqstate, dns.Fqdn(val), reqstate.QType())
+ if err != nil {
+ log.Printf("Got error %s\n", err)
+ return dns.RcodeServerFailure, fmt.Errorf("plugin/dnsfilter: %s", err)
+ }
+ if result != nil {
+ for _, answer := range result.Answer {
+ answer.Header().Name = question.Name
}
- if result != nil {
- for _, answer := range result.Answer {
- answer.Header().Name = question.Name
- }
- records = result.Answer
- cacheentry.answer = result.Answer
- cacheentry.lastUpdated = time.Now()
- lookupCache[val] = cacheentry
- }
- } else {
- // get from cache
- records = cacheentry.answer
+ records = result.Answer
}
}
m := new(dns.Msg)
diff --git a/dnsfilter/dnsfilter.go b/dnsfilter/dnsfilter.go
index 5fb5d0ed..c34cd590 100644
--- a/dnsfilter/dnsfilter.go
+++ b/dnsfilter/dnsfilter.go
@@ -17,7 +17,6 @@ import (
"sync/atomic"
"time"
- _ "github.com/benburkert/dns/init"
"github.com/bluele/gcache"
"golang.org/x/net/publicsuffix"
)