Initial QSfera import

Server/vendor/github.com/nats-io/nats-server/v2/server/nkey.go

@@ -0,0 +1,47 @@
+// Copyright 2018-2025 The NATS Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package server
+
+import (
+	crand "crypto/rand"
+	"encoding/base64"
+)
+
+// Raw length of the nonce challenge
+const (
+	nonceRawLen = 11
+	nonceLen    = 15 // base64.RawURLEncoding.EncodedLen(nonceRawLen)
+)
+
+// NonceRequired tells us if we should send a nonce.
+func (s *Server) NonceRequired() bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.nonceRequired()
+}
+
+// nonceRequired tells us if we should send a nonce.
+// Lock should be held on entry.
+func (s *Server) nonceRequired() bool {
+	return s.getOpts().AlwaysEnableNonce || len(s.nkeys) > 0 || s.trustedKeys != nil || len(s.proxiesKeyPairs) > 0
+}
+
+// Generate a nonce for INFO challenge.
+// Assumes server lock is held
+func (s *Server) generateNonce(n []byte) {
+	var raw [nonceRawLen]byte
+	data := raw[:]
+	crand.Read(data)
+	base64.RawURLEncoding.Encode(n, data)
+}