Java tutorial
/* * Copyright 2011-2012 the original author or authors. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package piuk.blockchain.android.util; import android.graphics.Bitmap; import android.graphics.Color; import android.text.Editable; import android.text.SpannableStringBuilder; import android.text.Spanned; import android.text.style.TypefaceSpan; import android.util.Pair; //import android.util.Log; import com.google.bitcoin.core.Address; import com.google.bitcoin.core.Base58; import com.google.bitcoin.core.DumpedPrivateKey; import com.google.bitcoin.core.ECKey; import com.google.bitcoin.core.NetworkParameters; import com.google.bitcoin.core.Utils; import com.google.bitcoin.params.MainNetParams; import com.google.zxing.BarcodeFormat; import com.google.zxing.EncodeHintType; import com.google.zxing.WriterException; import com.google.zxing.common.BitMatrix; import com.google.zxing.qrcode.QRCodeWriter; import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel; import piuk.blockchain.android.Hash; import piuk.blockchain.android.MyWallet; import piuk.blockchain.android.Constants; import java.io.DataOutputStream; import java.math.BigInteger; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLEncoder; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.Arrays; import java.util.Hashtable; import java.util.Map; import java.util.Map.Entry; import javax.crypto.Cipher; import javax.crypto.spec.SecretKeySpec; import org.apache.commons.io.IOUtils; import org.apache.commons.lang.ArrayUtils; import org.spongycastle.asn1.sec.SECNamedCurves; import org.spongycastle.crypto.generators.SCrypt; import org.spongycastle.util.encoders.Hex; /** * @author Andreas Schildbach */ public class WalletUtils { public final static QRCodeWriter QR_CODE_WRITER = new QRCodeWriter(); public static final int DefaultRequestRetry = 2; public static final int DefaultRequestTimeout = 60000; public static ECKey parsePrivateKey(String format, String contents, String password) throws Exception { if (format.equals("sipa") || format.equals("compsipa")) { DumpedPrivateKey pk = new DumpedPrivateKey(MainNetParams.get(), contents); return pk.getKey(); } else if (format.equals("base58")) { return MyWallet.decodeBase58PK(contents); } else if (format.equals("base64")) { return MyWallet.decodeBase64PK(contents); } else if (format.equals("hex")) { return MyWallet.decodeHexPK(contents); } else if (format.equals("bip38")) { return parseBIP38(contents, password); } else { throw new Exception("Unable to handle format " + format); } } public static String postURLWithParams(String request, Map<Object, Object> params) throws Exception { StringBuffer urlParameters = new StringBuffer(); for (Entry<Object, Object> entry : params.entrySet()) { urlParameters .append(entry.getKey() + "=" + URLEncoder.encode(entry.getValue().toString(), "UTF-8") + "&"); } return postURL(request, urlParameters.toString()); } public static String postURL(String request, String urlParameters) throws Exception { String error = null; for (int ii = 0; ii < DefaultRequestRetry; ++ii) { URL url = new URL(request); HttpURLConnection connection = (HttpURLConnection) url.openConnection(); try { connection.setDoOutput(true); connection.setDoInput(true); connection.setInstanceFollowRedirects(false); connection.setRequestMethod("POST"); connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); connection.setRequestProperty("charset", "utf-8"); connection.setRequestProperty("Accept", "application/json"); connection.setRequestProperty("Content-Length", "" + Integer.toString(urlParameters.getBytes().length)); connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.57 Safari/537.36"); connection.setUseCaches(false); connection.setConnectTimeout(DefaultRequestTimeout); connection.setReadTimeout(DefaultRequestTimeout); connection.connect(); DataOutputStream wr = new DataOutputStream(connection.getOutputStream()); wr.writeBytes(urlParameters); wr.flush(); wr.close(); connection.setInstanceFollowRedirects(false); if (connection.getResponseCode() == 200) { // Log.d("postURL", "return code 200"); return IOUtils.toString(connection.getInputStream(), "UTF-8"); } else { error = IOUtils.toString(connection.getErrorStream(), "UTF-8"); // Log.d("postURL", "return code " + error); } Thread.sleep(5000); } finally { connection.disconnect(); } } throw new Exception("Inavlid Response " + error); } public static String getURL(String URL) throws Exception { URL url = new URL(URL); String error = null; for (int ii = 0; ii < DefaultRequestRetry; ++ii) { HttpURLConnection connection = (HttpURLConnection) url.openConnection(); try { connection.setRequestMethod("GET"); connection.setRequestProperty("charset", "utf-8"); connection.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.57 Safari/537.36"); connection.setConnectTimeout(DefaultRequestTimeout); connection.setReadTimeout(DefaultRequestTimeout); connection.setInstanceFollowRedirects(false); connection.connect(); if (connection.getResponseCode() == 200) return IOUtils.toString(connection.getInputStream(), "UTF-8"); else error = IOUtils.toString(connection.getErrorStream(), "UTF-8"); Thread.sleep(5000); } finally { connection.disconnect(); } } return error; } public static String detectPrivateKeyFormat(String key) throws Exception { // 51 characters base58, always starts with a '5' if (key.matches("^5[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{50}$")) return "sipa"; if (key.matches("^[LK][123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{51}$")) return "compsipa"; // 52 characters base58 if (key.matches("^[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{44}$") || key.matches("^[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{43}$")) return "base58"; if (key.matches("^[A-Fa-f0-9]{64}$")) return "hex"; if (key.matches("^[ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789=+]{44}$")) return "base64"; if (key.matches("^6P[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{56}$")) return "bip38"; if (key.matches("^S[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{21}$") || key.matches("^S[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{25}$") || key.matches("^S[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{29}$") || key.matches("^S[123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz]{30}$")) { byte[] testBytes = SHA256(key + "?").getBytes(); if (testBytes[0] == 0x00 || testBytes[0] == 0x01) return "mini"; } throw new Exception("Unknown Key Format"); } public static String SHA256Hex(String str) { try { return new String(Hex.encode(MessageDigest.getInstance("SHA-256").digest(str.getBytes("UTF-8"))), "UTF-8"); } catch (Exception e) { e.printStackTrace(); return null; } } public static Hash SHA256(String str) { try { return new Hash(MessageDigest.getInstance("SHA-256").digest(str.getBytes("UTF-8"))); } catch (Exception e) { e.printStackTrace(); return null; } } public static Bitmap getQRCodeBitmap(final String url, final int size) { try { final Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>(); hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); hints.put(EncodeHintType.MARGIN, 2); final BitMatrix result = QR_CODE_WRITER.encode(url, BarcodeFormat.QR_CODE, size, size, hints); final int width = result.getWidth(); final int height = result.getHeight(); final int[] pixels = new int[width * height]; for (int y = 0; y < height; y++) { final int offset = y * width; for (int x = 0; x < width; x++) { pixels[offset + x] = result.get(x, y) ? Color.BLACK : Color.TRANSPARENT; } } final Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888); bitmap.setPixels(pixels, 0, width, 0, 0, width, height); return bitmap; } catch (final WriterException x) { x.printStackTrace(); return null; } } public static Editable formatAddress(final Address address, final int groupSize, final int lineSize) { return formatAddress(address.toString(), groupSize, lineSize); } public static Editable formatAddress(final String address, final int groupSize, final int lineSize) { final SpannableStringBuilder builder = new SpannableStringBuilder(); final int len = address.length(); for (int i = 0; i < len; i += groupSize) { final int end = i + groupSize; final String part = address.substring(i, end < len ? end : len); builder.append(part); builder.setSpan(new TypefaceSpan("monospace"), builder.length() - part.length(), builder.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); if (end < len) { final boolean endOfLine = end % lineSize == 0; builder.append(endOfLine ? "\n" : Constants.THIN_SPACE); } } return builder; } public static String formatValue(final BigInteger value) { return formatValue(value, "", "-"); } public static String formatValue(final BigInteger value, final String plusSign, final String minusSign) { final boolean negative = value.compareTo(BigInteger.ZERO) < 0; final BigInteger absValue = value.abs(); final String sign = negative ? minusSign : plusSign; final int coins = absValue.divide(Utils.COIN).intValue(); final int cents = absValue.remainder(Utils.COIN).intValue(); if (cents % 1000000 == 0) return String.format("%s%d.%02d", sign, coins, cents / 1000000); else if (cents % 10000 == 0) return String.format("%s%d.%04d", sign, coins, cents / 10000); else return String.format("%s%d.%08d", sign, coins, cents); } public static byte[] hash(byte[] data, int offset, int len) { try { MessageDigest a = MessageDigest.getInstance("SHA-256"); a.update(data, offset, len); return a.digest(a.digest()); } catch (NoSuchAlgorithmException e) { throw new RuntimeException(e); } } public static byte[] hash(byte[] data) { return hash(data, 0, data.length); } public static ECKey parseBIP38(String input, String password) throws Exception { byte[] store = Base58.decode(input); if (store.length != 43) { throw new Exception("invalid key length for BIP38"); } boolean ec = false; boolean compressed = false; boolean hasLot = false; if ((store[1] & 0xff) == 0x42) { if ((store[2] & 0xff) == 0xc0) { // non-EC-multiplied keys without compression (prefix 6PR) } else if ((store[2] & 0xff) == 0xe0) { // non-EC-multiplied keys with compression (prefix 6PY) compressed = true; } else { throw new Exception("invalid key"); } } else if ((store[1] & 0xff) == 0x43) { // EC-multiplied keys without compression (prefix 6Pf) // EC-multiplied keys with compression (prefix 6Pn) ec = true; compressed = (store[2] & 0x20) != 0; hasLot = (store[2] & 0x04) != 0; if ((store[2] & 0x24) != store[2]) { throw new Exception("invalid key"); } } else { throw new Exception("invalid key"); } byte[] checksum = new byte[4]; System.arraycopy(store, store.length - 4, checksum, 0, 4); byte[] ekey = new byte[store.length - 4]; System.arraycopy(store, 0, ekey, 0, store.length - 4); byte[] hash = hash(ekey); for (int i = 0; i < 4; ++i) { if (hash[i] != checksum[i]) { throw new Exception("checksum mismatch"); } } if (ec == false) { return parseBIP38NoEC(store, password, compressed); } else { return parseBIP38EC(store, password, compressed, hasLot); } } private static ECKey parseBIP38NoEC(byte[] store, String passphrase, boolean compressed) throws Exception { byte[] addressHash = new byte[4]; System.arraycopy(store, 3, addressHash, 0, 4); byte[] derived = SCrypt.generate(passphrase.getBytes("UTF-8"), addressHash, 16384, 8, 8, 64); byte[] key = new byte[32]; System.arraycopy(derived, 32, key, 0, 32); SecretKeySpec keyspec = new SecretKeySpec(key, "AES"); Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC"); cipher.init(Cipher.DECRYPT_MODE, keyspec); byte[] decrypted = cipher.doFinal(store, 7, 32); for (int i = 0; i < 32; ++i) { decrypted[i] ^= derived[i]; } byte[] appendZeroByte = ArrayUtils.addAll(new byte[1], decrypted); ECKey kp = new ECKey(new BigInteger(appendZeroByte)); String address = null; if (compressed) { address = kp.toAddressCompressed(MainNetParams.get()).toString(); } else { address = kp.toAddressUnCompressed(MainNetParams.get()).toString(); } byte[] acs = hash(address.toString().getBytes("US-ASCII")); byte[] check = new byte[4]; System.arraycopy(acs, 0, check, 0, 4); if (!Arrays.equals(check, addressHash)) { throw new Exception("failed to decrpyt"); } return kp; } private static ECKey parseBIP38EC(byte[] store, String passphrase, boolean compressed, boolean hasLot) throws Exception { byte[] addressHash = new byte[4]; System.arraycopy(store, 3, addressHash, 0, 4); byte[] ownentropy = new byte[8]; System.arraycopy(store, 7, ownentropy, 0, 8); byte[] ownersalt = ownentropy; if (hasLot) { ownersalt = new byte[4]; System.arraycopy(ownentropy, 0, ownersalt, 0, 4); } byte[] passfactor = SCrypt.generate(passphrase.getBytes("UTF-8"), ownersalt, 16384, 8, 8, 32); if (hasLot) { byte[] tmp = new byte[40]; System.arraycopy(passfactor, 0, tmp, 0, 32); System.arraycopy(ownentropy, 0, tmp, 32, 8); passfactor = hash(tmp); } byte[] appendZeroByte = ArrayUtils.addAll(new byte[1], passfactor); ECKey kp = new ECKey(new BigInteger(appendZeroByte)); byte[] salt = new byte[12]; System.arraycopy(store, 3, salt, 0, 12); byte[] derived = SCrypt.generate(kp.getPubKeyCompressed(), salt, 1024, 1, 1, 64); byte[] aeskey = new byte[32]; System.arraycopy(derived, 32, aeskey, 0, 32); SecretKeySpec keyspec = new SecretKeySpec(aeskey, "AES"); Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC"); cipher.init(Cipher.DECRYPT_MODE, keyspec); byte[] encrypted = new byte[16]; System.arraycopy(store, 23, encrypted, 0, 16); byte[] decrypted2 = cipher.doFinal(encrypted); for (int i = 0; i < 16; ++i) { decrypted2[i] ^= derived[i + 16]; } System.arraycopy(store, 15, encrypted, 0, 8); System.arraycopy(decrypted2, 0, encrypted, 8, 8); byte[] decrypted1 = cipher.doFinal(encrypted); for (int i = 0; i < 16; ++i) { decrypted1[i] ^= derived[i]; } byte[] seed = new byte[24]; System.arraycopy(decrypted1, 0, seed, 0, 16); System.arraycopy(decrypted2, 8, seed, 16, 8); BigInteger priv = new BigInteger(1, passfactor).multiply(new BigInteger(1, hash(seed))) .remainder(SECNamedCurves.getByName("secp256k1").getN()); kp = new ECKey(priv); String address = null; if (compressed) { address = kp.toAddressCompressed(MainNetParams.get()).toString(); } else { address = kp.toAddressUnCompressed(MainNetParams.get()).toString(); } byte[] acs = hash(address.getBytes("US-ASCII")); byte[] check = new byte[4]; System.arraycopy(acs, 0, check, 0, 4); if (!Arrays.equals(check, addressHash)) { throw new Exception("failed to decrpyt"); } return kp; } }