Initial commit

checker/starttls.go

@@ -0,0 +1,15 @@
+package checker
+
+import "net"
+
+// starttlsUpgrader performs the plaintext portion of a STARTTLS upgrade on
+// conn, leaving conn ready for tls.Client(conn, …).Handshake(). On success
+// the returned function returns nil; on failure it returns a descriptive
+// error (wrap errStartTLSNotOffered when the server advertises no STARTTLS).
+type starttlsUpgrader func(conn net.Conn, sni string) error
+
+var starttlsUpgraders = map[string]starttlsUpgrader{}
+
+func registerStartTLS(protocol string, upgrader starttlsUpgrader) {
+	starttlsUpgraders[protocol] = upgrader
+}