handle securityexceptions

* init with alt pin

* chain code in pubkeys

android/src/main/java/im/status/keycard/android/NFCCardChannel.java

@@ -24,14 +24,23 @@ public class NFCCardChannel implements CardChannel {
   public APDUResponse send(APDUCommand cmd) throws IOException {
     byte[] apdu = cmd.serialize();
     Log.d(TAG, String.format("COMMAND CLA: %02X INS: %02X P1: %02X P2: %02X LC: %02X", cmd.getCla(), cmd.getIns(), cmd.getP1(), cmd.getP2(), cmd.getData().length));
-    byte[] resp = this.isoDep.transceive(apdu);
-    APDUResponse response = new APDUResponse(resp);
-    Log.d(TAG, String.format("RESPONSE LEN: %02X, SW: %04X %n-----------------------", response.getData().length, response.getSw()));
-    return response;
+    
+    try {
+      byte[] resp = this.isoDep.transceive(apdu);
+      APDUResponse response = new APDUResponse(resp);
+      Log.d(TAG, String.format("RESPONSE LEN: %02X, SW: %04X %n-----------------------", response.getData().length, response.getSw()));
+      return response;
+    } catch(SecurityException e) {
+      throw new IOException("Tag disconnected", e);
+    }
   }
 
   @Override
   public boolean isConnected() {
-    return this.isoDep.isConnected();
+    try {
+      return this.isoDep.isConnected();
+    } catch(SecurityException e) {
+      return false;
+    }
   }
 }

android/src/main/java/im/status/keycard/android/NFCCardManager.java

@@ -48,7 +48,11 @@ public class NFCCardManager extends Thread implements NfcAdapter.ReaderCallback
    * @return if connected, false otherwise
    */
   public boolean isConnected() {
-    return isoDep != null && isoDep.isConnected();
+    try {
+      return isoDep != null && isoDep.isConnected();
+    } catch (SecurityException e) {
+      return false;
+    }
   }
 
   @Override
@@ -58,7 +62,7 @@ public class NFCCardManager extends Thread implements NfcAdapter.ReaderCallback
       isoDep = IsoDep.get(tag);
       isoDep.connect();
       isoDep.setTimeout(120000);
-    } catch (IOException e) {
+    } catch (IOException | SecurityException e) {
       Log.e(TAG, "error connecting to tag");
     }
   }

lib/src/main/java/im/status/keycard/applet/BIP32KeyPair.java

@@ -66,13 +66,13 @@ public class BIP32KeyPair {
       tlv.unreadLastTag();
       privKey = tlv.readPrimitive(TLV_PRIV_KEY);
       tag = tlv.readTag();
-
-      if (tag == TLV_CHAIN_CODE) {
-        tlv.unreadLastTag();
-        chainCode = tlv.readPrimitive(TLV_CHAIN_CODE);
-      }
     }
 
+    if (tag == TLV_CHAIN_CODE) {
+      tlv.unreadLastTag();
+      chainCode = tlv.readPrimitive(TLV_CHAIN_CODE);
+    }    
+
     return new BIP32KeyPair(privKey, chainCode, pubKey);
   }
 

lib/src/main/java/im/status/keycard/applet/CashCommandSet.java

@@ -32,6 +32,18 @@ public class CashCommandSet {
     return apduChannel.send(selectApplet);
   }
 
+  /**
+   * Sends an IDENTIFY CARD APDU. The challenge is sent as APDU data as-is. It must be 32 bytes long
+   *
+   * @param challenge the data of the APDU
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse identifyCard(byte[] challenge) throws IOException {
+    APDUCommand identifyCard = new APDUCommand(0x80, KeycardCommandSet.INS_IDENTIFY_CARD, 0, 0, challenge);
+    return apduChannel.send(identifyCard);
+  }  
+
   /**
    * Sends a SIGN APDU.
    *

lib/src/main/java/im/status/keycard/applet/Certificate.java

@@ -0,0 +1,141 @@
+package im.status.keycard.applet;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.security.KeyFactory;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.MessageDigest;
+import java.security.SecureRandom;
+import java.security.Signature;
+import java.security.spec.ECGenParameterSpec;
+
+import org.bouncycastle.jce.ECNamedCurveTable;
+import org.bouncycastle.jce.interfaces.ECPublicKey;
+import org.bouncycastle.jce.spec.ECParameterSpec;
+import org.bouncycastle.jce.interfaces.ECPrivateKey;
+import org.bouncycastle.jce.spec.ECPublicKeySpec;
+import org.bouncycastle.util.Arrays;
+
+public class Certificate extends RecoverableSignature {
+  public static final byte TLV_CERT = (byte) 0x8A;
+
+  private byte[] identPriv;
+  private byte[] identPub;
+  
+  public Certificate(byte[] publicKey, boolean compressed, byte[] r, byte[] s, int recId) {
+    super(publicKey, compressed,r, s, recId);
+  }
+
+  public static KeyPair generateIdentKeyPair() {
+    try {
+      KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("ECDSA", "BC");
+      ECGenParameterSpec spec = new ECGenParameterSpec("secp256k1");
+      keyPairGenerator.initialize(spec, new SecureRandom());
+      return keyPairGenerator.generateKeyPair();
+    } catch(Exception e) {
+      throw new RuntimeException("Is BouncyCastle in the classpath?");
+    }
+  }
+
+  public static Certificate createCertificate(KeyPair caPair, KeyPair identKeys) {
+    try {
+      byte[] pub = ((ECPublicKey) identKeys.getPublic()).getQ().getEncoded(true);
+
+      MessageDigest md = MessageDigest.getInstance("SHA256", "BC");
+      byte[] hash = md.digest(pub);
+
+      Signature signer = Signature.getInstance("NONEwithECDSA", "BC");
+      signer.initSign(caPair.getPrivate());
+      signer.update(hash);
+      byte[] sig = signer.sign();
+
+      TinyBERTLV tlv = new TinyBERTLV(sig);
+      tlv.enterConstructed(TLV_ECDSA_TEMPLATE);
+      byte[] r = toUInt(tlv.readPrimitive(TinyBERTLV.TLV_INT));
+      byte[] s = toUInt(tlv.readPrimitive(TinyBERTLV.TLV_INT));      
+      Certificate cert = new Certificate(((ECPublicKey)caPair.getPublic()).getQ().getEncoded(true), true, r, s, -1);
+      cert.calculateRecID(hash);
+      cert.identPriv = toUInt(((ECPrivateKey) identKeys.getPrivate()).getD().toByteArray());
+      cert.identPub = pub;
+
+      return cert;
+    } catch(IllegalArgumentException e) {
+      throw e;
+    } catch(Exception e) {
+      throw new RuntimeException("Is BouncyCastle in the classpath?");
+    }
+  }
+
+  public static Certificate generateNewCertificate(KeyPair caPair) {
+    return createCertificate(caPair, generateIdentKeyPair());
+  }
+
+  public static Certificate fromTLV(byte[] certData) {
+    try {
+      byte[] pub = Arrays.copyOfRange(certData, 0, 33);
+      byte[] r = Arrays.copyOfRange(certData, 33, 65);
+      byte[] s = Arrays.copyOfRange(certData, 65, 97);
+      int recId = certData[97];
+
+      MessageDigest md = MessageDigest.getInstance("SHA256", "BC");
+      byte[] hash = md.digest(pub);
+      byte[] caPub = recoverFromSignature(recId, hash, r, s, true);
+
+      Certificate cert = new Certificate(caPub, true, r, s, recId);
+      cert.identPub = pub;
+  
+      return cert;
+    } catch(IllegalArgumentException e) {
+      throw e;
+    } catch(Exception e) {
+      throw new RuntimeException("Is BouncyCastle in the classpath?");
+    } 
+  }
+
+  public static byte[] verifyIdentity(byte[] hash, byte[] tlvData) {
+    try {
+      TinyBERTLV tlv = new TinyBERTLV(tlvData);
+      tlv.enterConstructed(TLV_SIGNATURE_TEMPLATE);
+      byte[] certData = tlv.readPrimitive(TLV_CERT);
+      Certificate cert = fromTLV(certData);
+      byte[] signature = tlv.peekUnread();
+      Signature verifier = Signature.getInstance("NONEWithECDSA", "BC");
+
+      ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec("secp256k1");
+      ECPublicKeySpec cardKeySpec = new ECPublicKeySpec(ecSpec.getCurve().decodePoint(cert.identPub), ecSpec);
+      ECPublicKey cardKey = (ECPublicKey) KeyFactory.getInstance("ECDSA", "BC").generatePublic(cardKeySpec);
+
+      verifier.initVerify(cardKey);
+      verifier.update(hash);
+      
+      if (!verifier.verify(signature)) {
+        return null;
+      }
+
+      return cert.getPublicKey();
+    } catch(Exception e) {
+      throw new RuntimeException("Is BouncyCastle in the classpath?");
+    }     
+  }
+
+  public byte[] toStoreData() {
+    if (identPriv == null) {
+      throw new IllegalStateException("The private key must be set.");
+    }
+
+    ByteArrayOutputStream os = new ByteArrayOutputStream();
+    
+    try {
+      os.write(this.identPub);
+      os.write(this.getR());
+      os.write(this.getS());
+      os.write(this.getRecId());
+      os.write(this.identPriv);
+    } catch(IOException e) {
+      throw new RuntimeException(e);
+    }
+
+    return os.toByteArray();
+  }
+}

lib/src/main/java/im/status/keycard/applet/IdentCommandSet.java

@@ -0,0 +1,46 @@
+package im.status.keycard.applet;
+
+import im.status.keycard.io.APDUCommand;
+import im.status.keycard.io.APDUResponse;
+import im.status.keycard.io.CardChannel;
+
+import java.io.IOException;
+
+/**
+ * Command set for the Ident applet.
+ */
+public class IdentCommandSet {
+  private final CardChannel apduChannel;
+
+  /**
+   * Creates a IdentCommandSet using the given APDU Channel
+   * @param apduChannel APDU channel
+   */
+  public IdentCommandSet(CardChannel apduChannel) {
+    this.apduChannel = apduChannel;
+  }
+
+  /**
+   * Selects a Cash instance. The applet is assumed to have been installed with its default AID. The returned data is
+   * a public key which must be used to initialize the secure channel.
+   *
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse select() throws IOException {
+    APDUCommand selectApplet = new APDUCommand(0x00, 0xA4, 4, 0, Identifiers.IDENT_INSTANCE_AID);
+    return apduChannel.send(selectApplet);
+  }
+
+  /**
+   * Sends a STORE DATA APDU.
+   *
+   * @param data the data to sign
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse storeData(byte[] data) throws IOException {
+    APDUCommand sign = new APDUCommand(0x80, KeycardCommandSet.INS_STORE_DATA, 0x00, 0x00, data);
+    return apduChannel.send(sign);
+  }
+}

lib/src/main/java/im/status/keycard/applet/Identifiers.java

@@ -16,6 +16,9 @@ public class Identifiers {
   public static final byte[] CASH_AID = Hex.decode("A000000804000103");
   public static final byte[] CASH_INSTANCE_AID = Hex.decode("A00000080400010301");
 
+  public static final byte[] IDENT_AID = Hex.decode("A000000804000104");
+  public static final byte[] IDENT_INSTANCE_AID = Hex.decode("A00000080400010401");
+
   /**
    * Gets the instance AID of the default instance of the Keycard applet.
    *

lib/src/main/java/im/status/keycard/applet/KeycardCommandSet.java

@@ -20,6 +20,7 @@ public class KeycardCommandSet {
   static final byte INS_INIT = (byte) 0xFE;
   static final byte INS_GET_STATUS = (byte) 0xF2;
   static final byte INS_SET_NDEF = (byte) 0xF3;
+  static final byte INS_IDENTIFY_CARD = (byte) 0x14;
   static final byte INS_VERIFY_PIN = (byte) 0x20;
   static final byte INS_CHANGE_PIN = (byte) 0x21;
   static final byte INS_UNBLOCK_PIN = (byte) 0x22;
@@ -76,8 +77,9 @@ public class KeycardCommandSet {
   static final byte EXPORT_KEY_P1_DERIVE = 0x01;
   static final byte EXPORT_KEY_P1_DERIVE_AND_MAKE_CURRENT = 0x02;
 
-  static final byte EXPORT_KEY_P2_PRIVATE_AND_PUBLIC = 0x00;
-  static final byte EXPORT_KEY_P2_PUBLIC_ONLY = 0x01;
+  public static final byte EXPORT_KEY_P2_PRIVATE_AND_PUBLIC = 0x00;
+  public static final byte EXPORT_KEY_P2_PUBLIC_ONLY = 0x01;
+  public static final byte EXPORT_KEY_P2_EXTENDED_PUBLIC = 0x02;
 
   static final byte TLV_APPLICATION_INFO_TEMPLATE = (byte) 0xA4;
 
@@ -269,6 +271,18 @@ public class KeycardCommandSet {
     secureChannel.unpairOthers(apduChannel);
   }
 
+  /**
+   * Sends an IDENTIFY CARD APDU. The challenge is sent as APDU data as-is. It must be 32 bytes long
+   *
+   * @param challenge the data of the APDU
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse identifyCard(byte[] challenge) throws IOException {
+    APDUCommand identifyCard = secureChannel.protectedCommand(0x80, INS_IDENTIFY_CARD, 0, 0, challenge);
+    return secureChannel.transmit(apduChannel, identifyCard);
+  }
+
   /**
    * Sends a GET STATUS APDU. The info byte is the P1 parameter of the command, valid constants are defined in the applet
    * class itself.
@@ -540,7 +554,7 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse sign(byte[] data, int p1) throws IOException {
-    APDUCommand sign = secureChannel.protectedCommand(0x80, INS_SIGN, p1, 0x00, data);
+    APDUCommand sign = secureChannel.protectedCommand(0x80, INS_SIGN, p1, 0x01, data);
     return secureChannel.transmit(apduChannel, sign);
   }
 
@@ -620,6 +634,10 @@ public class KeycardCommandSet {
     return secureChannel.transmit(apduChannel, setPinlessPath);
   }
 
+  private byte poToP2(boolean publicOnly) {
+    return publicOnly ? EXPORT_KEY_P2_PUBLIC_ONLY : EXPORT_KEY_P2_PRIVATE_AND_PUBLIC;
+  }
+
   /**
    * Sends an EXPORT KEY APDU to export the current key.
    *
@@ -628,9 +646,20 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse exportCurrentKey(boolean publicOnly) throws IOException {
-    return exportKey(EXPORT_KEY_P1_CURRENT, publicOnly, new byte[0]);
+    return exportCurrentKey(poToP2(publicOnly));
   }
 
+  /**
+   * Sends an EXPORT KEY APDU to export the current key.
+   *
+   * @param p2 the p2 parameter
+   * @return the raw card reponse
+   * @throws IOException communication error
+   */
+  public APDUResponse exportCurrentKey(byte p2) throws IOException {
+    return exportKey(EXPORT_KEY_P1_CURRENT, p2, new byte[0]);
+  }  
+
   /**
    * Sends an EXPORT KEY APDU. Performs derivation of the given keypath and optionally makes it the current key.
    *
@@ -641,10 +670,23 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse exportKey(String keyPath, boolean makeCurrent, boolean publicOnly) throws IOException {
-    KeyPath path = new KeyPath(keyPath);
-    return exportKey(path.getData(), path.getSource(), makeCurrent, publicOnly);
+    return exportKey(keyPath, makeCurrent, poToP2(publicOnly));
   }
 
+  /**
+   * Sends an EXPORT KEY APDU. Performs derivation of the given keypath and optionally makes it the current key.
+   *
+   * @param keyPath the keypath to export
+   * @param makeCurrent if the key should be made current or not
+   * @param p2 the P2 parameter
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse exportKey(String keyPath, boolean makeCurrent, byte p2) throws IOException {
+    KeyPath path = new KeyPath(keyPath);
+    return exportKey(path.getData(), path.getSource(), makeCurrent, p2);
+  }  
+
   /**
    * Sends an EXPORT KEY APDU. Performs derivation of the given keypath and optionally makes it the current key.
    *
@@ -655,10 +697,23 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse exportKey(byte[] keyPath, int source, boolean makeCurrent, boolean publicOnly) throws IOException {
-    int p1 = source | (makeCurrent ? EXPORT_KEY_P1_DERIVE_AND_MAKE_CURRENT : EXPORT_KEY_P1_DERIVE);
-    return exportKey(p1, publicOnly, keyPath);
+    return exportKey(keyPath, source, makeCurrent, poToP2(publicOnly));
   }
 
+  /**
+   * Sends an EXPORT KEY APDU. Performs derivation of the given keypath and optionally makes it the current key.
+   *
+   * @param keyPath the keypath to export
+   * @param makeCurrent if the key should be made current or not
+   * @param p2 the P2 parameter
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse exportKey(byte[] keyPath, int source, boolean makeCurrent, byte p2) throws IOException {
+    int p1 = source | (makeCurrent ? EXPORT_KEY_P1_DERIVE_AND_MAKE_CURRENT : EXPORT_KEY_P1_DERIVE);
+    return exportKey(p1, p2, keyPath);
+  }  
+
   /**
    * Sends an EXPORT KEY APDU. The parameters are sent as-is.
    *
@@ -669,10 +724,22 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse exportKey(int derivationOptions, boolean publicOnly, byte[] keypath) throws IOException {
-    byte p2 = publicOnly ? EXPORT_KEY_P2_PUBLIC_ONLY : EXPORT_KEY_P2_PRIVATE_AND_PUBLIC;
+    return exportKey(derivationOptions, poToP2(publicOnly), keypath);
+  }
+
+  /**
+   * Sends an EXPORT KEY APDU. The parameters are sent as-is.
+   *
+   * @param derivationOptions the P1 parameter
+   * @param p2 the P2 parameter
+   * @param keypath the data parameter
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse exportKey(int derivationOptions, byte p2, byte[] keypath) throws IOException {
     APDUCommand exportKey = secureChannel.protectedCommand(0x80, INS_EXPORT_KEY, derivationOptions, p2, keypath);
     return secureChannel.transmit(apduChannel, exportKey);
-  }
+  }  
 
   /**
    * Sends a GET DATA APDU.
@@ -748,9 +815,25 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse init(String pin, String puk, String pairingPassword, byte pinRetries, byte pukRetries) throws IOException {
-    return this.init(pin, puk, pairingPasswordToSecret(pairingPassword), pinRetries, pukRetries);
+    return this.init(pin, null, puk, pairingPasswordToSecret(pairingPassword), pinRetries, pukRetries);
   }
 
+  /**
+   * Sends the INIT command to the card.
+   *
+   * @param pin the PIN
+   * @param altPin the alternative PIN
+   * @param puk the PUK
+   * @param pairingPassword pairing password
+   * @param pinRetries the number of allowed PIN retries
+   * @param pukRetries the number of allowed PUK retries
+   * @return the raw card response
+   * @throws IOException communication error
+   */
+  public APDUResponse init(String pin, String altPin, String puk, String pairingPassword, byte pinRetries, byte pukRetries) throws IOException {
+    return this.init(pin, altPin, puk, pairingPasswordToSecret(pairingPassword), pinRetries, pukRetries);
+  }  
+
   /**
    * Sends the INIT command to the card.
    *
@@ -761,13 +844,14 @@ public class KeycardCommandSet {
    * @throws IOException communication error
    */
   public APDUResponse init(String pin, String puk, byte[] sharedSecret) throws IOException {
-    return init(pin, puk, sharedSecret, (byte) 0, (byte) 0);
+    return init(pin, null, puk, sharedSecret, (byte) 0, (byte) 0);
   }
 
   /**
    * Sends the INIT command to the card. If either pinRetries or pukRetries is zero, neither will be sent.
    *
    * @param pin the PIN
+   * @param pin the alternative
    * @param puk the PUK
    * @param sharedSecret the shared secret for pairing
    * @param pinRetries the number of allowed PIN retries
@@ -775,15 +859,29 @@ public class KeycardCommandSet {
    * @return the raw card response
    * @throws IOException communication error
    */
-  public APDUResponse init(String pin, String puk, byte[] sharedSecret, byte pinRetries, byte pukRetries) throws IOException {
-    boolean addRetries = !((pinRetries == 0) || (pukRetries == 0));
-    byte[] initData = Arrays.copyOf(pin.getBytes(), pin.length() + puk.length() + sharedSecret.length + (addRetries ? 2 : 0));
+  public APDUResponse init(String pin, String altPin, String puk, byte[] sharedSecret, byte pinRetries, byte pukRetries) throws IOException {
+    int baselen = pin.length() + puk.length() + sharedSecret.length;
+    int extlen;
+
+    if (altPin != null) {
+      extlen = 2 + altPin.length();
+    } else if ((pinRetries != 0) || (pukRetries != 0)) {
+      extlen = 2;
+    } else {
+      extlen = 0;
+    }
+    
+    byte[] initData = Arrays.copyOf(pin.getBytes(), baselen + extlen);
     System.arraycopy(puk.getBytes(), 0, initData, pin.length(), puk.length());
     System.arraycopy(sharedSecret, 0, initData, pin.length() + puk.length(), sharedSecret.length);
 
-    if (addRetries) {
-      initData[initData.length - 2] = pinRetries;
-      initData[initData.length - 1] = pukRetries;
+    if (extlen > 0) {
+      initData[baselen] = pinRetries;
+      initData[baselen + 1] = pukRetries;
+
+      if (extlen > 2) {
+        System.arraycopy(altPin.getBytes(), 0, initData, baselen + 2, altPin.length());
+      }
     }
 
     APDUCommand init = new APDUCommand(0x80, INS_INIT, 0, 0, secureChannel.oneShotEncrypt(initData));

lib/src/main/java/im/status/keycard/applet/Mnemonic.java

@@ -124,7 +124,7 @@ public class Mnemonic {
       PBEKeySpec spec = new PBEKeySpec(mnemonicPhrase.toCharArray(), ("mnemonic" + password).getBytes(), 2048, 512);
       key = skf.generateSecret(spec);
     } catch (Exception e) {
-      throw new RuntimeException("Is Bouncycastle correctly initialized?");
+      throw new RuntimeException("Is Bouncycastle correctly initialized?", e);
     }
 
     return key.getEncoded();

lib/src/main/java/im/status/keycard/applet/RecoverableSignature.java

@@ -20,8 +20,10 @@ public class RecoverableSignature {
   private int recId;
   private byte[] r;
   private byte[] s;
+  private boolean compressed;
 
   public static final byte TLV_SIGNATURE_TEMPLATE = (byte) 0xA0;
+  public static final byte TLV_RAW_SIGNATURE = (byte) 0x80;
   public static final byte TLV_ECDSA_TEMPLATE = (byte) 0x30;
 
   private static final X9ECParameters CURVE_PARAMS = CustomNamedCurves.getByName("secp256k1");
@@ -40,16 +42,50 @@ public class RecoverableSignature {
    */
   public RecoverableSignature(byte[] hash, byte[] tlvData) {
     TinyBERTLV tlv = new TinyBERTLV(tlvData);
-    tlv.enterConstructed(TLV_SIGNATURE_TEMPLATE);
-    publicKey = tlv.readPrimitive(ApplicationInfo.TLV_PUB_KEY);
-    tlv.enterConstructed(TLV_ECDSA_TEMPLATE);
-    r = toUInt(tlv.readPrimitive(TinyBERTLV.TLV_INT));
-    s = toUInt(tlv.readPrimitive(TinyBERTLV.TLV_INT));
+    int tag = tlv.readTag();
+    tlv.unreadLastTag();
 
+    if (tag == TLV_RAW_SIGNATURE) {
+      initFromRawSignature(hash, tlv.readPrimitive(tag));
+    } else if (tag == TLV_SIGNATURE_TEMPLATE) {
+      initFromLegacy(hash, tlv);
+    } else {
+      throw new IllegalArgumentException("invalid tlv");
+    }
+  }
+
+  private void initFromLegacy(byte[] hash, TinyBERTLV tlv) {
+    tlv.enterConstructed(TLV_SIGNATURE_TEMPLATE);
+    this.publicKey = tlv.readPrimitive(ApplicationInfo.TLV_PUB_KEY);
+    tlv.enterConstructed(TLV_ECDSA_TEMPLATE);
+    this.r = toUInt(tlv.readPrimitive(TinyBERTLV.TLV_INT));
+    this.s = toUInt(tlv.readPrimitive(TinyBERTLV.TLV_INT));
+    this.compressed = false;
+
+    calculateRecID(hash);
+  }
+
+  private void initFromRawSignature(byte[] hash, byte[] signature) {
+    this.r = Arrays.copyOfRange(signature, 0, 32);
+    this.s = Arrays.copyOfRange(signature, 32, 64);
+    this.recId = signature[64];
+    this.compressed = false;
+    this.publicKey = recoverFromSignature(this.recId, hash, this.r, this.s, this.compressed);
+  }
+
+  public RecoverableSignature(byte[] publicKey, boolean compressed, byte[] r, byte[] s, int recId) {
+    this.publicKey = publicKey;
+    this.r = r;
+    this.s = s;
+    this.compressed = compressed;
+    this.recId = recId;
+  }
+
+  void calculateRecID(byte[] hash) {
     recId = -1;
 
     for (int i = 0; i < 4; i++) {
-      byte[] candidate = recoverFromSignature(i, new BigInteger(1, hash), new BigInteger(1, r), new BigInteger(1, s));
+      byte[] candidate = recoverFromSignature(i, hash, r, s, compressed);
 
       if (Arrays.equals(candidate, publicKey)) {
         recId = i;
@@ -62,7 +98,7 @@ public class RecoverableSignature {
     }
   }
 
-  private byte[] toUInt(byte[] signedInt) {
+  static byte[] toUInt(byte[] signedInt) {
     if (signedInt[0] == 0) {
       return Arrays.copyOfRange(signedInt, 1, signedInt.length);
     } else {
@@ -114,7 +150,15 @@ public class RecoverableSignature {
     return Ethereum.toEthereumAddress(publicKey);
   }
 
-  private static byte[] recoverFromSignature(int recId, BigInteger e, BigInteger r, BigInteger s) {
+  static byte[] recoverFromSignature(int recId, byte[] hash, byte[] r, byte[] s, boolean compressed) {
+    BigInteger h = new BigInteger(1, hash);
+    BigInteger br = new BigInteger(1, r);
+    BigInteger bs = new BigInteger(1, s);
+
+    return recoverFromSignature(recId, h, br, bs, compressed);
+  }
+
+  static byte[] recoverFromSignature(int recId, BigInteger e, BigInteger r, BigInteger s, boolean compressed) {
     BigInteger n = CURVE.getN();
     BigInteger i = BigInteger.valueOf((long) recId / 2);
     BigInteger x = r.add(i.multiply(n));
@@ -135,7 +179,7 @@ public class RecoverableSignature {
     BigInteger srInv = rInv.multiply(s).mod(n);
     BigInteger eInvrInv = rInv.multiply(eInv).mod(n);
     ECPoint q = ECAlgorithms.sumOfTwoMultiplies(CURVE.getG(), eInvrInv, R, srInv);
-    return q.getEncoded(false);
+    return q.getEncoded(compressed);
   }
 
   private static ECPoint decompressKey(BigInteger xBN, boolean yBit) {

lib/src/main/java/im/status/keycard/applet/TinyBERTLV.java

@@ -119,6 +119,15 @@ public class TinyBERTLV {
     return TinyBERTLV.readVal(val, 0, val.length);
   }
 
+  /**
+   * Returns all unread bytes in the TLV.
+   * 
+   * @return all unread bytes
+   */
+  byte[] peekUnread() {
+    return Arrays.copyOfRange(buffer, pos, buffer.length);
+  }
+
   /**
    * Low-level method to unread the last read tag. Only valid if the previous call was readTag(). Does nothing if the
    * end of the TLV has been reached.

lib/src/main/java/im/status/keycard/globalplatform/GlobalPlatformCommandSet.java

@@ -250,6 +250,16 @@ public class GlobalPlatformCommandSet {
     return delete(Identifiers.NDEF_INSTANCE_AID);
   }
 
+  /**
+   * Deletes the Ident applet instance.
+   *
+   * @return the card response
+   * @throws IOException communication error
+   */
+  public APDUResponse deleteIdentInstance() throws IOException {
+    return delete(Identifiers.IDENT_INSTANCE_AID);
+  }  
+
   /**
    * Deletes the Keycard package.
    *
@@ -268,10 +278,7 @@ public class GlobalPlatformCommandSet {
    * @throws IOException communication error
    */
   public void deleteKeycardInstancesAndPackage() throws IOException, APDUException {
-    deleteNDEFInstance().checkSW(APDUResponse.SW_OK, APDUResponse.SW_REFERENCED_DATA_NOT_FOUND);
-    deleteKeycardInstance().checkSW(APDUResponse.SW_OK, APDUResponse.SW_REFERENCED_DATA_NOT_FOUND);
-    deleteCashInstance().checkSW(APDUResponse.SW_OK, APDUResponse.SW_REFERENCED_DATA_NOT_FOUND);
-    deleteKeycardPackage().checkSW(APDUResponse.SW_OK, APDUResponse.SW_REFERENCED_DATA_NOT_FOUND);
+    delete(Identifiers.PACKAGE_AID, (byte) 0x80).checkSW(APDUResponse.SW_OK, APDUResponse.SW_REFERENCED_DATA_NOT_FOUND);
   }
 
   /**
@@ -282,15 +289,27 @@ public class GlobalPlatformCommandSet {
    * @throws IOException communication error.
    */
   public APDUResponse delete(byte[] aid) throws IOException {
+    return delete(aid, (byte) 0);
+  }
+
+  /**
+   * Sends a DELETE APDU with the given AID
+   * @param aid the AID to the delete
+   * @param p2 the P2 value
+   * @return the raw card response
+   *
+   * @throws IOException communication error.
+   */
+  public APDUResponse delete(byte[] aid, byte p2) throws IOException {
     byte[] data = new byte[aid.length + 2];
     data[0] = 0x4F;
     data[1] = (byte) aid.length;
     System.arraycopy(aid, 0, data, 2, aid.length);
 
-    APDUCommand cmd = new APDUCommand(0x80, INS_DELETE, 0, 0, data);
+    APDUCommand cmd = new APDUCommand(0x80, INS_DELETE, 0, p2, data);
 
     return this.secureChannel.send(cmd);
-  }
+  }  
 
   /**
    * Loads the Keycard package.
@@ -448,4 +467,14 @@ public class GlobalPlatformCommandSet {
   public APDUResponse installCashApplet() throws IOException {
     return installCashApplet(new byte[0]);
   }
+
+  /**
+   * Installs the Ident applet.
+   *
+   * @return the card response
+   * @throws IOException communication error.
+   */
+  public APDUResponse installIdentApplet() throws IOException {
+    return installForInstall(Identifiers.PACKAGE_AID, Identifiers.IDENT_AID, Identifiers.IDENT_INSTANCE_AID, new byte[0]);
+  }  
 }