Java tutorial
/* Copyright 2014 The MITRE Corporation 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. This project contains content developed by The MITRE Corporation. If this code is used in a deployment or embedded within another project, it is requested that you send an email to opensource@mitre.org in order to let us know where this software is being used. */ package org.mitre.secretsharing.server; import java.io.IOException; import java.security.SecureRandom; import java.util.ArrayList; import java.util.List; import java.util.Random; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.mitre.secretsharing.Part; import org.mitre.secretsharing.Secrets; import com.fasterxml.jackson.annotation.JsonInclude; import com.fasterxml.jackson.annotation.JsonInclude.Include; import com.fasterxml.jackson.core.Base64Variants; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.PropertyNamingStrategy; public class SplitServlet extends HttpServlet { /** * */ private static final long serialVersionUID = 1L; private static Random rnd = new SecureRandom(); public static class Request { public String secret; public Integer totalParts; public Integer requiredParts; public Boolean base64; } @JsonInclude(Include.NON_NULL) public static class Response { public String status; public List<String> parts; } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { ObjectMapper mapper = new ObjectMapper(); mapper.setPropertyNamingStrategy(PropertyNamingStrategy.CAMEL_CASE_TO_LOWER_CASE_WITH_UNDERSCORES); resp.setContentType("application/json"); try { Request jreq = mapper.readValue(req.getParameter("q"), Request.class); byte[] secret; if (jreq.base64 != null && jreq.base64) secret = Base64Variants.MIME_NO_LINEFEEDS.decode(jreq.secret); else secret = jreq.secret.getBytes("UTF-8"); if (jreq.secret == null || jreq.totalParts == null || jreq.requiredParts == null) throw new IllegalArgumentException(); Part[] parts = Secrets.splitPerByte(secret, jreq.totalParts, jreq.requiredParts, rnd); Response jresp = new Response(); jresp.parts = new ArrayList<String>(); for (Part part : parts) jresp.parts.add(part.toString()); jresp.status = "ok"; mapper.writeValue(resp.getOutputStream(), jresp); } catch (Throwable t) { t.printStackTrace(); Response jresp = new Response(); jresp.status = "error"; mapper.writeValue(resp.getOutputStream(), jresp); } } }