initial commit

handler/dns/metadata.go

@@ -0,0 +1,41 @@
+package dns
+
+import (
+	"net"
+	"time"
+
+	mdata "github.com/go-gost/gost/v3/pkg/metadata"
+)
+
+type metadata struct {
+	readTimeout time.Duration
+	ttl         time.Duration
+	timeout     time.Duration
+	clientIP    net.IP
+	// nameservers
+	dns []string
+}
+
+func (h *dnsHandler) parseMetadata(md mdata.Metadata) (err error) {
+	const (
+		readTimeout = "readTimeout"
+		ttl         = "ttl"
+		timeout     = "timeout"
+		clientIP    = "clientIP"
+		dns         = "dns"
+	)
+
+	h.md.readTimeout = mdata.GetDuration(md, readTimeout)
+	h.md.ttl = mdata.GetDuration(md, ttl)
+	h.md.timeout = mdata.GetDuration(md, timeout)
+	if h.md.timeout <= 0 {
+		h.md.timeout = 5 * time.Second
+	}
+	sip := mdata.GetString(md, clientIP)
+	if sip != "" {
+		h.md.clientIP = net.ParseIP(sip)
+	}
+	h.md.dns = mdata.GetStrings(md, dns)
+
+	return
+}