[chore] Validate/set account domain (#619)

* add miekg/dns dependency

* set/validate accountDomain

vendor/golang.org/x/net/ipv6/icmp_bsd.go

@@ -0,0 +1,30 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build aix || darwin || dragonfly || freebsd || netbsd || openbsd
+// +build aix darwin dragonfly freebsd netbsd openbsd
+
+package ipv6
+
+func (f *icmpv6Filter) accept(typ ICMPType) {
+	f.Filt[typ>>5] |= 1 << (uint32(typ) & 31)
+}
+
+func (f *icmpv6Filter) block(typ ICMPType) {
+	f.Filt[typ>>5] &^= 1 << (uint32(typ) & 31)
+}
+
+func (f *icmpv6Filter) setAll(block bool) {
+	for i := range f.Filt {
+		if block {
+			f.Filt[i] = 0
+		} else {
+			f.Filt[i] = 1<<32 - 1
+		}
+	}
+}
+
+func (f *icmpv6Filter) willBlock(typ ICMPType) bool {
+	return f.Filt[typ>>5]&(1<<(uint32(typ)&31)) == 0
+}