add http3 reverse proxy

handler/http3/metadata.go

@@ -0,0 +1,56 @@
+package http3
+
+import (
+	"net/http"
+	"strings"
+
+	mdata "github.com/go-gost/core/metadata"
+	mdutil "github.com/go-gost/core/metadata/util"
+)
+
+type metadata struct {
+	probeResistance *probeResistance
+	header          http.Header
+	hash            string
+}
+
+func (h *http3Handler) parseMetadata(md mdata.Metadata) error {
+	const (
+		header          = "header"
+		probeResistKey  = "probeResistance"
+		probeResistKeyX = "probe_resist"
+		knock           = "knock"
+		hash            = "hash"
+	)
+
+	if m := mdutil.GetStringMapString(md, header); len(m) > 0 {
+		hd := http.Header{}
+		for k, v := range m {
+			hd.Add(k, v)
+		}
+		h.md.header = hd
+	}
+
+	pr := mdutil.GetString(md, probeResistKey)
+	if pr == "" {
+		pr = mdutil.GetString(md, probeResistKeyX)
+	}
+	if pr != "" {
+		if ss := strings.SplitN(pr, ":", 2); len(ss) == 2 {
+			h.md.probeResistance = &probeResistance{
+				Type:  ss[0],
+				Value: ss[1],
+				Knock: mdutil.GetString(md, knock),
+			}
+		}
+	}
+	h.md.hash = mdutil.GetString(md, hash)
+
+	return nil
+}
+
+type probeResistance struct {
+	Type  string
+	Value string
+	Knock string
+}