Completely refactor certificates and implement renewal & cleanup

helpers.go

@@ -0,0 +1,21 @@
+package main
+
+import "bytes"
+
+// GetHSTSHeader returns a HSTS header with includeSubdomains & preload for MainDomainSuffix and RawDomain, or an empty
+// string for custom domains.
+func GetHSTSHeader(host []byte) string {
+	if bytes.HasSuffix(host, MainDomainSuffix) || bytes.Equal(host, RawDomain) {
+		return "max-age=63072000; includeSubdomains; preload"
+	} else {
+		return ""
+	}
+}
+
+func TrimHostPort(host []byte) []byte {
+	i := bytes.IndexByte(host, ':')
+	if i >= 0 {
+		return host[:i]
+	}
+	return host
+}