kwin commented on a change in pull request #5: URL: https://github.com/apache/sling-org-apache-sling-scripting-core/pull/5#discussion_r578696764
########## File path: src/main/java/org/apache/sling/scripting/core/impl/ScriptingVariablesNonceFactory.java ########## @@ -0,0 +1,70 @@ +/* + * Copyright 2016 The Apache Software Foundation. + * + * 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 org.apache.sling.scripting.core.impl; + +import java.security.SecureRandom; + +import org.apache.commons.collections4.map.LRUMap; + +/** + * Factory for generating one-time-use tokens for the + * ScriptingVariablesConsolePlugin + SlingBindingsVariablesListJsonServlet + * transactions. + */ +final class ScriptingVariablesNonceFactory { + private static final String EMPTY_STRING = ""; + private static final SecureRandom secureRandom = new SecureRandom(); + // use LRUMap so it is not possible to grow indefinitely if isValid is + // never called after nextNonce is called + private static final LRUMap<String, String> validNonceSet = new LRUMap<>(100); + + /** + * Generate a random use once value + * + * @return random nonce value + */ + public static String nextNonce() { + byte[] nonce = new byte[8]; + secureRandom.nextBytes(nonce); + String nonceHex = convertBytesToHex(nonce); + validNonceSet.put(nonceHex, EMPTY_STRING); + return nonceHex; + } + + /** + * Check if the supplied value matches one of the + * previously generated single use values + * + * @return true if the nonce was valid, false otherwise + */ + public static boolean isValid(String nonce) { + Object remove = validNonceSet.remove(nonce); Review comment: For performance reasons we could also consider using the less secure HmacSha1 (https://docs.oracle.com/javase/8/docs/api/javax/crypto/Mac.html). ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
