sni: work with non-ssl

go.mod

@@ -7,6 +7,7 @@ require (
 	git.torproject.org/pluggable-transports/obfs4.git v0.0.0-20181103133120-08f4d470188e
 	github.com/LiamHaworth/go-tproxy v0.0.0-20190726054950-ef7efd7f24ed
 	github.com/Yawning/chacha20 v0.0.0-20170904085104-e3b1f968fc63 // indirect
+	github.com/asaskevich/govalidator v0.0.0-20200108200545-475eaeb16496
 	github.com/bifurcation/mint v0.0.0-20181105071958-a14404e9a861 // indirect
 	github.com/cheekybits/genny v1.0.0 // indirect
 	github.com/coreos/go-iptables v0.4.5 // indirect

go.sum

@@ -10,6 +10,8 @@ github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da h1:KjTM2ks9d14ZYCvmH
 github.com/aead/chacha20 v0.0.0-20180709150244-8b13a72661da/go.mod h1:eHEWzANqSiWQsof+nXEI9bUVUyV6F53Fp89EuCh2EAA=
 github.com/agl/ed25519 v0.0.0-20170116200512-5312a6153412 h1:w1UutsfOrms1J05zt7ISrnJIXKzwaspym5BTKGx93EI=
 github.com/agl/ed25519 v0.0.0-20170116200512-5312a6153412/go.mod h1:WPjqKcmVOxf0XSf3YxCJs6N6AOSrOx3obionmG7T0y0=
+github.com/asaskevich/govalidator v0.0.0-20200108200545-475eaeb16496 h1:zV3ejI06GQ59hwDQAvmK1qxOQGB3WuVTRoY0okPTAv0=
+github.com/asaskevich/govalidator v0.0.0-20200108200545-475eaeb16496/go.mod h1:oGkLhpf+kjZl6xBf758TQhh5XrAeiJv/7FRz/2spLIg=
 github.com/bifurcation/mint v0.0.0-20181105071958-a14404e9a861 h1:x17NvoJaphEzay72TFej4OSSsgu3xRYBLkbIwdofS/4=
 github.com/bifurcation/mint v0.0.0-20181105071958-a14404e9a861/go.mod h1:zVt7zX3K/aDCk9Tj+VM7YymsX66ERvzCJzw8rFCX2JU=
 github.com/cheekybits/genny v1.0.0 h1:uGGa4nei+j20rOSeDeP5Of12XVm7TGUd4dJA9RDitfE=

sni.go

@@ -17,6 +17,7 @@ import (
 	"strings"
 	"sync"
 
+	"github.com/asaskevich/govalidator"
 	dissector "github.com/ginuerzh/tls-dissector"
 	"github.com/go-log/log"
 )
@@ -86,6 +87,10 @@ func (h *sniHandler) Handle(conn net.Conn) {
 			return
 		}
 
+		if !req.URL.IsAbs() && govalidator.IsDNSName(req.Host) {
+			req.URL.Scheme = "http"
+		}
+
 		handler := &httpHandler{options: h.options}
 		handler.Init()
 		handler.handleRequest(conn, req)