diff options
Diffstat (limited to 'plugin/forward/forward.go')
| -rw-r--r-- | plugin/forward/forward.go | 49 |
1 files changed, 30 insertions, 19 deletions
diff --git a/plugin/forward/forward.go b/plugin/forward/forward.go index 223d7e398..927a6e21f 100644 --- a/plugin/forward/forward.go +++ b/plugin/forward/forward.go @@ -16,6 +16,7 @@ import ( "github.com/coredns/coredns/plugin/dnstap" "github.com/coredns/coredns/plugin/metadata" clog "github.com/coredns/coredns/plugin/pkg/log" + "github.com/coredns/coredns/plugin/pkg/proxy" "github.com/coredns/coredns/request" "github.com/miekg/dns" @@ -25,12 +26,17 @@ import ( var log = clog.NewWithPlugin("forward") +const ( + defaultExpire = 10 * time.Second + hcInterval = 500 * time.Millisecond +) + // Forward represents a plugin instance that can proxy requests to another (DNS) server. It has a list // of proxies each representing one upstream proxy. type Forward struct { concurrent int64 // atomic counters need to be first in struct for proper alignment - proxies []*Proxy + proxies []*proxy.Proxy p Policy hcInterval time.Duration @@ -43,7 +49,7 @@ type Forward struct { expire time.Duration maxConcurrent int64 - opts options // also here for testing + opts proxy.Options // also here for testing // ErrLimitExceeded indicates that a query was rejected because the number of concurrent queries has exceeded // the maximum allowed (maxConcurrent) @@ -56,14 +62,14 @@ type Forward struct { // New returns a new Forward. func New() *Forward { - f := &Forward{maxfails: 2, tlsConfig: new(tls.Config), expire: defaultExpire, p: new(random), from: ".", hcInterval: hcInterval, opts: options{forceTCP: false, preferUDP: false, hcRecursionDesired: true, hcDomain: "."}} + f := &Forward{maxfails: 2, tlsConfig: new(tls.Config), expire: defaultExpire, p: new(random), from: ".", hcInterval: hcInterval, opts: proxy.Options{ForceTCP: false, PreferUDP: false, HCRecursionDesired: true, HCDomain: "."}} return f } // SetProxy appends p to the proxy list and starts healthchecking. -func (f *Forward) SetProxy(p *Proxy) { +func (f *Forward) SetProxy(p *proxy.Proxy) { f.proxies = append(f.proxies, p) - p.start(f.hcInterval) + p.Start(f.hcInterval) } // SetTapPlugin appends one or more dnstap plugins to the tap plugin list. @@ -128,12 +134,12 @@ func (f *Forward) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg if span != nil { child = span.Tracer().StartSpan("connect", ot.ChildOf(span.Context())) - otext.PeerAddress.Set(child, proxy.addr) + otext.PeerAddress.Set(child, proxy.Addr()) ctx = ot.ContextWithSpan(ctx, child) } metadata.SetValueFunc(ctx, "forward/upstream", func() string { - return proxy.addr + return proxy.Addr() }) var ( @@ -141,14 +147,15 @@ func (f *Forward) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg err error ) opts := f.opts + for { ret, err = proxy.Connect(ctx, state, opts) if err == ErrCachedClosed { // Remote side closed conn, can only happen with TCP. continue } // Retry with TCP if truncated and prefer_udp configured. - if ret != nil && ret.Truncated && !opts.forceTCP && opts.preferUDP { - opts.forceTCP = true + if ret != nil && ret.Truncated && !opts.ForceTCP && opts.PreferUDP { + opts.ForceTCP = true continue } break @@ -159,7 +166,7 @@ func (f *Forward) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg } if len(f.tapPlugins) != 0 { - toDnstap(f, proxy.addr, state, opts, ret, start) + toDnstap(f, proxy.Addr(), state, opts, ret, start) } upstreamErr = err @@ -219,13 +226,13 @@ func (f *Forward) isAllowedDomain(name string) bool { } // ForceTCP returns if TCP is forced to be used even when the request comes in over UDP. -func (f *Forward) ForceTCP() bool { return f.opts.forceTCP } +func (f *Forward) ForceTCP() bool { return f.opts.ForceTCP } // PreferUDP returns if UDP is preferred to be used even when the request comes in over TCP. -func (f *Forward) PreferUDP() bool { return f.opts.preferUDP } +func (f *Forward) PreferUDP() bool { return f.opts.PreferUDP } // List returns a set of proxies to be used for this client depending on the policy in f. -func (f *Forward) List() []*Proxy { return f.p.List(f.proxies) } +func (f *Forward) List() []*proxy.Proxy { return f.p.List(f.proxies) } var ( // ErrNoHealthy means no healthy proxies left. @@ -236,12 +243,16 @@ var ( ErrCachedClosed = errors.New("cached connection was closed by peer") ) -// options holds various options that can be set. -type options struct { - forceTCP bool - preferUDP bool - hcRecursionDesired bool - hcDomain string +// Options holds various Options that can be set. +type Options struct { + // ForceTCP use TCP protocol for upstream DNS request. Has precedence over PreferUDP flag + ForceTCP bool + // PreferUDP use UDP protocol for upstream DNS request. + PreferUDP bool + // HCRecursionDesired sets recursion desired flag for Proxy healthcheck requests + HCRecursionDesired bool + // HCDomain sets domain for Proxy healthcheck requests + HCDomain string } var defaultTimeout = 5 * time.Second |