Java tutorial
/* * Copyright (C) 2012-2014 Dominik Schrmann <dominik@dominikschuermann.de> * Copyright (C) 2011 Thialfihar <thi@thialfihar.org> * Copyright (C) 2011 Senecaso * * 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.thialfihar.android.apg.pgp; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.NameValuePair; import org.apache.http.client.HttpClient; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.apache.http.util.EntityUtils; import org.thialfihar.android.apg.Constants; import org.thialfihar.android.apg.ui.adapter.ImportKeysListEntry; import org.thialfihar.android.apg.util.Log; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.UnsupportedEncodingException; import java.net.HttpURLConnection; import java.net.InetAddress; import java.net.MalformedURLException; import java.net.URL; import java.net.URLDecoder; import java.net.URLEncoder; import java.net.UnknownHostException; import java.util.ArrayList; import java.util.GregorianCalendar; import java.util.List; import java.util.Locale; import java.util.TimeZone; import java.util.regex.Matcher; import java.util.regex.Pattern; public class HkpKeyServer extends KeyServer { private static class HttpError extends Exception { private static final long serialVersionUID = 1718783705229428893L; private int mCode; private String mData; public HttpError(int code, String data) { super("" + code + ": " + data); mCode = code; mData = data; } public int getCode() { return mCode; } public String getData() { return mData; } } private String mHost; private short mPort; /** * pub:%keyid%:%algo%:%keylen%:%creationdate%:%expirationdate%:%flags% * <ul> * <li>%<b>keyid</b>% = this is either the fingerprint or the key ID of the key. Either the * 16-digit or 8-digit * key IDs are acceptable, but obviously the fingerprint is best.</li> * <li>%<b>algo</b>% = the algorithm number, (i.e. 1==RSA, 17==DSA, etc). * See <a href="http://tools.ietf.org/html/rfc2440#section-9.1">RFC-2440</a></li> * <li>%<b>keylen</b>% = the key length (i.e. 1024, 2048, 4096, etc.)</li> * <li>%<b>creationdate</b>% = creation date of the key in standard * <a href="http://tools.ietf.org/html/rfc2440#section-9.1">RFC-2440</a> form (i.e. number of * seconds since * 1/1/1970 UTC time)</li> * <li>%<b>expirationdate</b>% = expiration date of the key in standard * <a href="http://tools.ietf.org/html/rfc2440#section-9.1">RFC-2440</a> form (i.e. number of * seconds since * 1/1/1970 UTC time)</li> * <li>%<b>flags</b>% = letter codes to indicate details of the key, if any. Flags may be in * any order. The * meaning of "disabled" is implementation-specific. Note that individual flags may be * unimplemented, so * the absence of a given flag does not necessarily mean the absence of the detail. * <ul> * <li>r == revoked</li> * <li>d == disabled</li> * <li>e == expired</li> * </ul> * </li> * </ul> * * @see <a href="http://tools.ietf.org/html/draft-shaw-openpgp-hkp-00#section-5.2">5.2. Machine * Readable Indexes</a> * in Internet-Draft OpenPGP HTTP Keyserver Protocol Document */ public static final Pattern PUB_KEY_LINE = Pattern.compile( "pub:([0-9a-fA-F]+):([0-9]+):([0-9]+):([0-9]+):([0-9]*):([rde]*)[ \n\r]*" // pub line + "(uid:(.*):([0-9]+):([0-9]*):([rde]*))+", // one or more uid lines Pattern.CASE_INSENSITIVE); /** * uid:%escaped uid string%:%creationdate%:%expirationdate%:%flags% * <ul> * <li>%<b>escaped uid string</b>% = the user ID string, with HTTP %-escaping for anything that * isn't 7-bit * safe as well as for the ":" character. Any other characters may be escaped, as desired.</li> * <li>%<b>creationdate</b>% = creation date of the key in standard * <a href="http://tools.ietf.org/html/rfc2440#section-9.1">RFC-2440</a> form (i.e. number of * seconds since * 1/1/1970 UTC time)</li> * <li>%<b>expirationdate</b>% = expiration date of the key in standard * <a href="http://tools.ietf.org/html/rfc2440#section-9.1">RFC-2440</a> form (i.e. number of * seconds since * 1/1/1970 UTC time)</li> * <li>%<b>flags</b>% = letter codes to indicate details of the key, if any. Flags may be in * any order. The * meaning of "disabled" is implementation-specific. Note that individual flags may be * unimplemented, so * the absence of a given flag does not necessarily mean the absence of the detail. * <ul> * <li>r == revoked</li> * <li>d == disabled</li> * <li>e == expired</li> * </ul> * </li> * </ul> */ public static final Pattern UID_LINE = Pattern.compile("uid:(.*):([0-9]+):([0-9]*):([rde]*)", Pattern.CASE_INSENSITIVE); private static final short PORT_DEFAULT = 11371; /** * @param hostAndPort may be just * "<code>hostname</code>" (eg. "<code>pool.sks-keyservers.net</code>"), then * it will * connect using {@link #PORT_DEFAULT}. However, port may be specified after * colon * ("<code>hostname:port</code>", eg. "<code>p80.pool.sks-keyservers.net:80</code>"). */ public HkpKeyServer(String hostAndPort) { String host = hostAndPort; short port = PORT_DEFAULT; final int colonPosition = hostAndPort.lastIndexOf(':'); if (colonPosition > 0) { host = hostAndPort.substring(0, colonPosition); final String portStr = hostAndPort.substring(colonPosition + 1); port = Short.decode(portStr); } mHost = host; mPort = port; } public HkpKeyServer(String host, short port) { mHost = host; mPort = port; } private static String readAll(InputStream in, String encoding) throws IOException { ByteArrayOutputStream raw = new ByteArrayOutputStream(); byte buffer[] = new byte[1 << 16]; int n = 0; while ((n = in.read(buffer)) != -1) { raw.write(buffer, 0, n); } if (encoding == null) { encoding = "utf8"; } return raw.toString(encoding); } private String query(String request) throws QueryException, HttpError { InetAddress ips[]; try { ips = InetAddress.getAllByName(mHost); } catch (UnknownHostException e) { throw new QueryException(e.toString()); } for (int i = 0; i < ips.length; ++i) { try { String url = "http://" + ips[i].getHostAddress() + ":" + mPort + request; Log.d(Constants.TAG, "hkp keyserver query: " + url); URL realUrl = new URL(url); HttpURLConnection conn = (HttpURLConnection) realUrl.openConnection(); conn.setConnectTimeout(5000); conn.setReadTimeout(25000); conn.connect(); int response = conn.getResponseCode(); if (response >= 200 && response < 300) { return readAll(conn.getInputStream(), conn.getContentEncoding()); } else { String data = readAll(conn.getErrorStream(), conn.getContentEncoding()); throw new HttpError(response, data); } } catch (MalformedURLException e) { // nothing to do, try next IP } catch (IOException e) { // nothing to do, try next IP } } throw new QueryException("querying server(s) for '" + mHost + "' failed"); } @Override public ArrayList<ImportKeysListEntry> search(String query) throws QueryException, TooManyResponses, InsufficientQuery { ArrayList<ImportKeysListEntry> results = new ArrayList<ImportKeysListEntry>(); if (query.length() < 3) { throw new InsufficientQuery(); } String encodedQuery; try { encodedQuery = URLEncoder.encode(query, "utf8"); } catch (UnsupportedEncodingException e) { return null; } String request = "/pks/lookup?op=index&options=mr&search=" + encodedQuery; String data; try { data = query(request); } catch (HttpError e) { if (e.getCode() == 404) { return results; } else { if (e.getData().toLowerCase(Locale.US).contains("no keys found")) { return results; } else if (e.getData().toLowerCase(Locale.US).contains("too many")) { throw new TooManyResponses(); } else if (e.getData().toLowerCase(Locale.US).contains("insufficient")) { throw new InsufficientQuery(); } } throw new QueryException("querying server(s) for '" + mHost + "' failed"); } final Matcher matcher = PUB_KEY_LINE.matcher(data); while (matcher.find()) { final ImportKeysListEntry entry = new ImportKeysListEntry(); entry.setBitStrength(Integer.parseInt(matcher.group(3))); final int algorithmId = Integer.decode(matcher.group(2)); entry.setAlgorithm(ImportKeysListEntry.getAlgorithmFromId(algorithmId)); // group 1 contains the full fingerprint (v4) or the long key id if available // see http://bit.ly/1d4bxbk and http://bit.ly/1gD1wwr String fingerprintOrKeyId = matcher.group(1); if (fingerprintOrKeyId.length() > 16) { entry.setFingerPrintHex(fingerprintOrKeyId.toLowerCase(Locale.US)); entry.setKeyIdHex("0x" + fingerprintOrKeyId.substring(fingerprintOrKeyId.length() - 16, fingerprintOrKeyId.length())); } else { // set key id only entry.setKeyIdHex("0x" + fingerprintOrKeyId); } final long creationDate = Long.parseLong(matcher.group(4)); final GregorianCalendar tmpGreg = new GregorianCalendar(TimeZone.getTimeZone("UTC")); tmpGreg.setTimeInMillis(creationDate * 1000); entry.setDate(tmpGreg.getTime()); entry.setRevoked(matcher.group(6).contains("r")); ArrayList<String> userIds = new ArrayList<String>(); final String uidLines = matcher.group(7); final Matcher uidMatcher = UID_LINE.matcher(uidLines); while (uidMatcher.find()) { String tmp = uidMatcher.group(1).trim(); if (tmp.contains("%")) { try { // converts Strings like "Universit%C3%A4t" to a proper encoding form "Universitt". tmp = (URLDecoder.decode(tmp, "UTF8")); } catch (UnsupportedEncodingException ignored) { // will never happen, because "UTF8" is supported } } userIds.add(tmp); } entry.setUserIds(userIds); results.add(entry); } return results; } @Override public String get(String keyIdHex) throws QueryException { HttpClient client = new DefaultHttpClient(); try { String query = "http://" + mHost + ":" + mPort + "/pks/lookup?op=get&options=mr&search=" + keyIdHex; Log.d(Constants.TAG, "hkp keyserver get: " + query); HttpGet get = new HttpGet(query); HttpResponse response = client.execute(get); if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) { throw new QueryException("not found"); } HttpEntity entity = response.getEntity(); InputStream is = entity.getContent(); String data = readAll(is, EntityUtils.getContentCharSet(entity)); Matcher matcher = PgpHelper.PGP_PUBLIC_KEY.matcher(data); if (matcher.find()) { return matcher.group(1); } } catch (IOException e) { // nothing to do, better luck on the next keyserver } finally { client.getConnectionManager().shutdown(); } return null; } @Override public void add(String armoredKey) throws AddKeyException { HttpClient client = new DefaultHttpClient(); try { String query = "http://" + mHost + ":" + mPort + "/pks/add"; HttpPost post = new HttpPost(query); Log.d(Constants.TAG, "hkp keyserver add: " + query); List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2); nameValuePairs.add(new BasicNameValuePair("keytext", armoredKey)); post.setEntity(new UrlEncodedFormEntity(nameValuePairs)); HttpResponse response = client.execute(post); if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) { throw new AddKeyException(); } } catch (IOException e) { // nothing to do, better luck on the next keyserver } finally { client.getConnectionManager().shutdown(); } } }