5 files changed, 248 insertions, 109 deletions

diff --git a/src/cz/crcs/ectester/applet/ECTesterApplet.java b/src/cz/crcs/ectester/applet/ECTesterApplet.java
index f304196..dd13fc3 100644
--- a/src/cz/crcs/ectester/applet/ECTesterApplet.java
+++ b/src/cz/crcs/ectester/applet/ECTesterApplet.java
@@ -1,4 +1,25 @@
 /*
+ * Copyright (c) 2016-2017 Petr Svenda <petr@svenda.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+/*
  * PACKAGEID: 4C6162616B417070
  * APPLETID: 4C6162616B4170706C6574
  */
@@ -11,6 +32,8 @@ import javacard.security.KeyPair;
 import javacard.security.RandomData;
 
 /**
+ * Reader part of ECTester, a tool for testing Elliptic curve support on javacards.
+ *
  * @author Petr Svenda petr@svenda.com
  * @author Jan Jancar johny@neuromancer.sk
  */
@@ -125,10 +148,10 @@ public class ECTesterApplet extends Applet {
     }
 
     /**
-     * Allocate local and remote keypairs.
+     * Allocates local and remote keyPairs.
      * returns allocate SWs
      *
-     * @param apdu P1   = byte keypair (KEYPAIR_* | ...)
+     * @param apdu P1   = byte keyPair (KEYPAIR_* | ...)
      *             P2   =
      *             DATA = short keyLength
      *             byte keyClass
@@ -137,32 +160,32 @@ public class ECTesterApplet extends Applet {
         apdu.setIncomingAndReceive();
         byte[] apdubuf = apdu.getBuffer();
 
-        byte keypair = apdubuf[ISO7816.OFFSET_P1];
+        byte keyPair = apdubuf[ISO7816.OFFSET_P1];
         short keyLength = Util.getShort(apdubuf, ISO7816.OFFSET_CDATA);
         byte keyClass = apdubuf[ISO7816.OFFSET_CDATA + 2];
 
-        short len = allocate(keypair, keyLength, keyClass, apdubuf, (short) 0);
+        short len = allocate(keyPair, keyLength, keyClass, apdubuf, (short) 0);
 
         apdu.setOutgoingAndSend((short) 0, len);
     }
 
     /**
-     * @param keypair   which keypair to use, local/remote (KEYPAIR_* | ...)
+     * @param keyPair   which keyPair to use, local/remote (KEYPAIR_* | ...)
      * @param keyLength key length to set
      * @param keyClass  key class to allocate
      * @param buffer    apdu buffer
      * @param offset    offset into apdu buffer
      * @return length of data written to the buffer
      */
-    private short allocate(byte keypair, short keyLength, byte keyClass, byte[] buffer, short offset) {
+    private short allocate(byte keyPair, short keyLength, byte keyClass, byte[] buffer, short offset) {
         short length = 0;
-        if ((keypair & KEYPAIR_LOCAL) != 0) {
+        if ((keyPair & KEYPAIR_LOCAL) != 0) {
             localKeypair = keyGenerator.allocatePair(keyClass, keyLength);
             Util.setShort(buffer, offset, keyGenerator.getSW());
             length += 2;
         }
 
-        if ((keypair & KEYPAIR_REMOTE) != 0) {
+        if ((keyPair & KEYPAIR_REMOTE) != 0) {
             remoteKeypair = keyGenerator.allocatePair(keyClass, keyLength);
             Util.setShort(buffer, (short) (offset + length), keyGenerator.getSW());
             length += 2;
@@ -172,10 +195,10 @@ public class ECTesterApplet extends Applet {
     }
 
     /**
-     * Sets curve parameters on local and remote keypairs.
+     * Sets curve parameters on local and remote keyPairs.
      * returns setCurve SWs, set params if export
      *
-     * @param apdu P1   = byte keypair (KEYPAIR_* | ...)
+     * @param apdu P1   = byte keyPair (KEYPAIR_* | ...)
      *             P2   = byte export (EXPORT_* | KEYPAIR_*)
      *             DATA = byte curve (EC_Consts.CURVE_*)
      *             short params (EC_Consts.PARAMETER_* | ...)
@@ -183,7 +206,7 @@ public class ECTesterApplet extends Applet {
      *             byte corruptionType (EC_Consts.CORRUPTION_*)
      *             <p>
      *             if curveID = CURVE_EXTERNAL:
-     *             [short param_length, byte[] param],
+     *             [short paramLength, byte[] param],
      *             for all params in params,
      *             in order: field,a,b,g,r,k,w,s
      */
@@ -191,7 +214,7 @@ public class ECTesterApplet extends Applet {
         apdu.setIncomingAndReceive();
         byte[] apdubuf = apdu.getBuffer();
 
-        byte keypair = apdubuf[ISO7816.OFFSET_P1];
+        byte keyPair = apdubuf[ISO7816.OFFSET_P1];
         byte export = apdubuf[ISO7816.OFFSET_P2];
         byte curve = apdubuf[ISO7816.OFFSET_CDATA];
         short params = Util.getShort(apdubuf, (short) (ISO7816.OFFSET_CDATA + 1));
@@ -200,9 +223,9 @@ public class ECTesterApplet extends Applet {
 
         short len = 0;
 
-        if ((keypair & KEYPAIR_LOCAL) != 0)
+        if ((keyPair & KEYPAIR_LOCAL) != 0)
             len += set(localKeypair, curve, params, corruptedParams, corruptionType, apdubuf, (short) (ISO7816.OFFSET_CDATA + 6), (short) 0);
-        if ((keypair & KEYPAIR_REMOTE) != 0)
+        if ((keyPair & KEYPAIR_REMOTE) != 0)
             len += set(remoteKeypair, curve, params, corruptedParams, corruptionType, apdubuf, (short) (ISO7816.OFFSET_CDATA + 6), len);
         if ((export & KEYPAIR_LOCAL) != 0)
             len += export(localKeypair, export, params, apdubuf, len);
@@ -213,7 +236,7 @@ public class ECTesterApplet extends Applet {
     }
 
     /**
-     * @param keypair    KeyPair to set params on
+     * @param keyPair    KeyPair to set params on
      * @param curve      curve to set (EC_Consts.CURVE_*)
      * @param params     parameters to set (EC_Consts.PARAMETER_* | ...)
      * @param corrupted  parameters to corrupt (EC_Consts.PARAMETER_* | ...)
@@ -223,7 +246,7 @@ public class ECTesterApplet extends Applet {
      * @param outOffset  output offset in buffer
      * @return length of data written to the buffer
      */
-    private short set(KeyPair keypair, byte curve, short params, short corrupted, byte corruption, byte[] buffer, short inOffset, short outOffset) {
+    private short set(KeyPair keyPair, byte curve, short params, short corrupted, byte corruption, byte[] buffer, short inOffset, short outOffset) {
         short sw = ISO7816.SW_NO_ERROR;
 
         switch (curve) {
@@ -232,38 +255,38 @@ public class ECTesterApplet extends Applet {
                 break;
             case EC_Consts.CURVE_external:
                 //external
-                sw = keyGenerator.setExternalCurve(keypair, params, buffer, inOffset);
+                sw = keyGenerator.setExternalCurve(keyPair, params, buffer, inOffset);
                 break;
             default:
                 //custom
-                sw = keyGenerator.setCurve(keypair, curve, params, ramArray, (short) 0);
+                sw = keyGenerator.setCurve(keyPair, curve, params, ramArray, (short) 0);
                 break;
         }
 
         if (sw == ISO7816.SW_NO_ERROR)
-            sw = keyGenerator.corruptCurve(keypair, corrupted, corruption, ramArray, (short) 0);
+            sw = keyGenerator.corruptCurve(keyPair, corrupted, corruption, ramArray, (short) 0);
         Util.setShort(buffer, outOffset, sw);
         return 2;
     }
 
     /**
-     * Generates the local and remote keypairs.
+     * Generates the local and remote keyPairs.
      * returns generate SWs, pubkey and privkey if export
      *
-     * @param apdu P1   = byte keypair (KEYPAIR_* | ...)
+     * @param apdu P1   = byte keyPair (KEYPAIR_* | ...)
      *             P2   = byte export (EXPORT_* | KEYPAIR_*)
      */
     private void insGenerate(APDU apdu) {
         apdu.setIncomingAndReceive();
         byte[] apdubuf = apdu.getBuffer();
 
-        byte keypair = apdubuf[ISO7816.OFFSET_P1];
+        byte keyPair = apdubuf[ISO7816.OFFSET_P1];
         byte export = apdubuf[ISO7816.OFFSET_P2];
 
         short len = 0;
-        if ((keypair & KEYPAIR_LOCAL) != 0)
+        if ((keyPair & KEYPAIR_LOCAL) != 0)
             len += generate(localKeypair, apdubuf, (short) 0);
-        if ((keypair & KEYPAIR_REMOTE) != 0)
+        if ((keyPair & KEYPAIR_REMOTE) != 0)
             len += generate(remoteKeypair, apdubuf, len);
         if ((export & KEYPAIR_LOCAL) != 0)
             len += export(localKeypair, export, (short) (EC_Consts.PARAMETER_W | EC_Consts.PARAMETER_S), apdubuf, len);
@@ -274,44 +297,44 @@ public class ECTesterApplet extends Applet {
     }
 
     /**
-     * @param keypair KeyPair to generate
+     * @param keyPair KeyPair to generate
      * @param buffer  buffer to write sw to
      * @param offset  output offset in buffer
      * @return length of data written to the buffer
      */
-    private short generate(KeyPair keypair, byte[] buffer, short offset) {
-        short sw = keyGenerator.generatePair(keypair);
+    private short generate(KeyPair keyPair, byte[] buffer, short offset) {
+        short sw = keyGenerator.generatePair(keyPair);
         Util.setShort(buffer, offset, sw);
 
         return 2;
     }
 
     /**
-     * @param keypair KeyPair to export from
+     * @param keyPair KeyPair to export from
      * @param export  which key to export from (EXPORT_PUBLIC | EXPORT_PRIVATE)
      * @param params  which params to export (EC_Consts.PARAMETER_* | ...)
      * @param buffer  buffer to export params to
      * @param offset  output offset in buffer
      * @return length of data written to the buffer
      */
-    private short export(KeyPair keypair, byte export, short params, byte[] buffer, short offset) {
+    private short export(KeyPair keyPair, byte export, short params, byte[] buffer, short offset) {
         short length = 0;
 
         if ((export & EXPORT_PUBLIC) != 0) {
             //export params from public
-            length += keyGenerator.exportParameters(keypair, ECKeyGenerator.KEY_PUBLIC, params, buffer, offset);
+            length += keyGenerator.exportParameters(keyPair, ECKeyGenerator.KEY_PUBLIC, params, buffer, offset);
         }
 
         if ((export & EXPORT_PRIVATE) != 0) {
             //export params from private
-            length += keyGenerator.exportParameters(keypair, ECKeyGenerator.KEY_PRIVATE, params, buffer, (short) (offset + length));
+            length += keyGenerator.exportParameters(keyPair, ECKeyGenerator.KEY_PRIVATE, params, buffer, (short) (offset + length));
 
         }
         return length;
     }
 
     /**
-     * Does ECDH, between the pubkey specified in P1(local/remote) and the privkey specified in P2(local/remote).
+     * Performs ECDH, between the pubkey specified in P1(local/remote) and the privkey specified in P2(local/remote).
      * returns deriveSecret SW, if export != 0 => short secretlen, byte[] secret
      *
      * @param apdu P1   = byte pubkey (KEYPAIR_*)
@@ -334,8 +357,8 @@ public class ECTesterApplet extends Applet {
     }
 
     /**
-     * @param pubkey  keypair to use for public key, (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
-     * @param privkey keypair to use for private key, (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
+     * @param pubkey  keyPair to use for public key, (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
+     * @param privkey keyPair to use for private key, (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
      * @param export  whether to export ECDH secret
      * @param invalid whether to invalidate the pubkey before ECDH
      * @param buffer  buffer to write sw to, and export ECDH secret if (export & EXPORT_ECDH) != 0
@@ -369,35 +392,35 @@ public class ECTesterApplet extends Applet {
     }
 
     /**
-     * Does and ECDSA signature and verification on data provided, using the keypair in P1(local/remote).
+     * Performs ECDSA signature and verification on data provided or random, using the keyPair in P1(local/remote).
      * returns ecdsa SW, if export != 0 => short signature_length, byte[] signature
      *
-     * @param apdu P1   = byte keypair (KEYPAIR_*)
+     * @param apdu P1   = byte keyPair (KEYPAIR_*)
      *             P2   = byte export (EXPORT_SIG || 0)
-     *             DATA = short data_length (00 = random data generated, !00 = data length)
+     *             DATA = short dataLength (00 = random data generated, !00 = data length)
      *             byte[] data
      */
     private void insECDSA(APDU apdu) {
         apdu.setIncomingAndReceive();
         byte[] apdubuf = apdu.getBuffer();
 
-        byte keypair = apdubuf[ISO7816.OFFSET_P1];
+        byte keyPair = apdubuf[ISO7816.OFFSET_P1];
         byte export = apdubuf[ISO7816.OFFSET_P2];
 
-        short len = ecdsa(keypair, export, apdubuf, ISO7816.OFFSET_CDATA, (short) 0);
+        short len = ecdsa(keyPair, export, apdubuf, ISO7816.OFFSET_CDATA, (short) 0);
 
         apdu.setOutgoingAndSend((short) 0, len);
     }
 
     /**
-     * @param keypair   keypair to use for signing and verification (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
+     * @param keyPair   keyPair to use for signing and verification (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
      * @param export    whether to export ECDSA signature
      * @param buffer    buffer to write sw to, and export ECDSA signature if (export & EXPORT_SIG) != 0
      * @param inOffset  input offset in buffer
      * @param outOffset output offset in buffer
      * @return length of data written to the buffer
      */
-    private short ecdsa(byte keypair, byte export, byte[] buffer, short inOffset, short outOffset) {
+    private short ecdsa(byte keyPair, byte export, byte[] buffer, short inOffset, short outOffset) {
         short length = 0;
 
         short dataLength = Util.getShort(buffer, inOffset);
@@ -409,7 +432,7 @@ public class ECTesterApplet extends Applet {
             Util.arrayCopyNonAtomic(buffer, (short) (inOffset + 2), ramArray, (short) 0, dataLength);
         }
 
-        KeyPair sign = ((keypair & KEYPAIR_LOCAL) != 0) ? localKeypair : remoteKeypair;
+        KeyPair sign = ((keyPair & KEYPAIR_LOCAL) != 0) ? localKeypair : remoteKeypair;
 
         short signatureLength = keyTester.testECDSA((ECPrivateKey) sign.getPrivate(), (ECPublicKey) sign.getPublic(), ramArray, (short) 0, dataLength, ramArray2, (short) 0);
         Util.setShort(buffer, outOffset, keyTester.getSW());
diff --git a/src/cz/crcs/ectester/reader/CardMngr.java b/src/cz/crcs/ectester/reader/CardMngr.java
index aab7da9..9cdd055 100644
--- a/src/cz/crcs/ectester/reader/CardMngr.java
+++ b/src/cz/crcs/ectester/reader/CardMngr.java
@@ -2,11 +2,11 @@ package cz.crcs.ectester.reader;
 
 import com.licel.jcardsim.io.CAD;
 import com.licel.jcardsim.io.JavaxSmartCardInterface;
-import java.util.List;
-import java.util.Scanner;
 import javacard.framework.AID;
 
 import javax.smartcardio.*;
+import java.util.List;
+import java.util.Scanner;
 
 /**
  * @author Petr Svenda petr@svenda.com
@@ -16,16 +16,16 @@ public class CardMngr {
     private CardTerminal terminal = null;
     private CardChannel channel = null;
     private Card card = null;
-    
+
     // Simulator related attributes
     private CAD cad = null;
     private JavaxSmartCardInterface simulator = null;
 
     private boolean simulate = false;
-    
+
     private final byte selectCM[] = {
-        (byte) 0x00, (byte) 0xa4, (byte) 0x04, (byte) 0x00, (byte) 0x07, (byte) 0xa0, (byte) 0x00, (byte) 0x00,
-        (byte) 0x00, (byte) 0x18, (byte) 0x43, (byte) 0x4d};
+            (byte) 0x00, (byte) 0xa4, (byte) 0x04, (byte) 0x00, (byte) 0x07, (byte) 0xa0, (byte) 0x00, (byte) 0x00,
+            (byte) 0x00, (byte) 0x18, (byte) 0x43, (byte) 0x4d};
 
     public static final byte OFFSET_CLA = 0x00;
     public static final byte OFFSET_INS = 0x01;
@@ -42,7 +42,7 @@ public class CardMngr {
         this(false);
     }
 
-    public CardMngr(boolean simulate)  {
+    public CardMngr(boolean simulate) {
         this.simulate = simulate;
     }
 
@@ -70,14 +70,14 @@ public class CardMngr {
 
                 //reset the card
                 System.out.println(Util.bytesToHex(card.getATR().getBytes()));
-                
+
                 cardFound = true;
             }
         }
 
         return cardFound;
     }
-    
+
     public boolean connectToCardSelect() throws CardException {
         if (simulate)
             return true;
@@ -113,7 +113,7 @@ public class CardMngr {
                 terminal = terminalList.get(answ);
             }
         }
-        
+
         if (terminal != null) {
             card = terminal.connect("*");
             System.out.println("card: " + card);
@@ -190,15 +190,15 @@ public class CardMngr {
             apdu[OFFSET_LC] = (byte) 0x00;
 
             ResponseAPDU resp = send(apdu);
-            
-            System.out.println("Response: " + Integer.toHexString(resp.getSW()));  
-            
+
+            System.out.println("Response: " + Integer.toHexString(resp.getSW()));
+
             if (resp.getSW() != 0x6D00) { // Note: 0x6D00 is SW_INS_NOT_SUPPORTED
                 // something?
             }
         }
     }
-    
+
     public static List<CardTerminal> getReaderList() {
         try {
             TerminalFactory factory = TerminalFactory.getDefault();
@@ -242,14 +242,14 @@ public class CardMngr {
         CommandAPDU commandAPDU = new CommandAPDU(apdu);
         return sendAPDU(commandAPDU);
     }
-    
+
     public boolean prepareLocalSimulatorApplet(byte[] appletAIDArray, byte[] installData, Class appletClass) {
         System.setProperty("com.licel.jcardsim.terminal.type", "2");
         cad = new CAD(System.getProperties());
         simulator = (JavaxSmartCardInterface) cad.getCardInterface();
         AID appletAID = new AID(appletAIDArray, (short) 0, (byte) appletAIDArray.length);
 
-        AID appletAIDRes =  simulator.installApplet(appletAID, appletClass, installData, (short) 0, (byte) installData.length);
+        AID appletAIDRes = simulator.installApplet(appletAID, appletClass, installData, (short) 0, (byte) installData.length);
         return simulator.selectApplet(appletAID);
     }
 
diff --git a/src/cz/crcs/ectester/reader/ECTester.java b/src/cz/crcs/ectester/reader/ECTester.java
index 6d1be42..1ee0015 100644
--- a/src/cz/crcs/ectester/reader/ECTester.java
+++ b/src/cz/crcs/ectester/reader/ECTester.java
@@ -1,3 +1,24 @@
+/*
+ * Copyright (c) 2016-2017 Petr Svenda <petr@svenda.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
 package cz.crcs.ectester.reader;
 
 import cz.crcs.ectester.applet.ECTesterApplet;
@@ -8,14 +29,17 @@ import org.apache.commons.cli.*;
 import javax.smartcardio.CardException;
 import javax.smartcardio.CommandAPDU;
 import javax.smartcardio.ResponseAPDU;
+import java.io.File;
 import java.io.FileNotFoundException;
-import java.io.FileOutputStream;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.nio.file.Files;
 import java.util.ArrayList;
 import java.util.List;
 
 /**
+ * Reader part of ECTester, a tool for testing Elliptic curve support on javacards.
+ *
  * @author Petr Svenda petr@svenda.com
  * @author Jan Jancar johny@neuromancer.sk
  */
@@ -23,7 +47,6 @@ public class ECTester {
 
     private CardMngr cardManager = null;
     private DirtyLogger systemOutLogger = null;
-    private FileOutputStream outputFile = null;
 
     //Options
     private int optBits;
@@ -56,7 +79,7 @@ public class ECTester {
     private static final byte[] ALLOCATE = {
             (byte) 0xB0,
             (byte) 0x5a, //INS  ALLOCATE
-            (byte) 0x00, //P1   *byte keypair
+            (byte) 0x00, //P1   *byte keyPair
             (byte) 0x00, //P2
             (byte) 0x03, //LC
             (byte) 0x00, //DATA *short keyLength
@@ -67,7 +90,7 @@ public class ECTester {
     private static final byte[] SET = {
             (byte) 0xB0,
             (byte) 0x5B, //INS  SET
-            (byte) 0x00, //P1   *byte keypair
+            (byte) 0x00, //P1   *byte keyPair
             (byte) 0x00, //P2   *byte export
             (byte) 0x06, //LC
             (byte) 0x00, //DATA *byte curve
@@ -82,7 +105,7 @@ public class ECTester {
     private static final byte[] GENERATE = {
             (byte) 0xB0,
             (byte) 0x5C, //INS  GENERATE
-            (byte) 0x00, //P1   *byte keypair
+            (byte) 0x00, //P1   *byte keyPair
             (byte) 0x00, //P2   *byte export
             (byte) 0x00  //LC
     };
@@ -90,7 +113,7 @@ public class ECTester {
     private static final byte[] ECDH = {
             (byte) 0xB0,
             (byte) 0x5D, //INS  ECDH
-            (byte) 0x00, //P1   *byte keypair
+            (byte) 0x00, //P1   *byte keyPair
             (byte) 0x00, //P2   *byte export
             (byte) 0x01, //LC
             (byte) 0x00  //DATA *byte valid
@@ -99,7 +122,7 @@ public class ECTester {
     private static final byte[] ECDSA = {
             (byte) 0xB0,
             (byte) 0x5E, //INS ECDSA
-            (byte) 0x00, //P1   *byte keypair
+            (byte) 0x00, //P1   *byte keyPair
             (byte) 0x00, //P2   *byte export
             (byte) 0x00, //LC
             //DATA [*short dataLength, byte[] data]
@@ -177,6 +200,13 @@ public class ECTester {
         }
     }
 
+    /**
+     * Parses command-line options.
+     *
+     * @param args cli arguments
+     * @return parsed CommandLine object
+     * @throws ParseException if there are any problems encountered while parsing the command line tokens
+     */
     private CommandLine parseArgs(String[] args) throws ParseException {
         /*
          * Actions:
@@ -221,7 +251,7 @@ public class ECTester {
         opts.addOption(Option.builder("f2m").longOpt("binary-field").desc("Use binary field curve.").build());
         opts.addOption(Option.builder("pub").longOpt("public").desc("Use public key from file [pubkey_file] (wx,wy).").hasArg().argName("pubkey_file").build());
         opts.addOption(Option.builder("priv").longOpt("private").desc("Use private key from file [privkey_file] (s).").hasArg().argName("privkey_file").build());
-        opts.addOption(Option.builder("k").longOpt("key").desc("Use keypair from file [key_file] (wx,wy,s).").hasArg().argName("key_file").build());
+        opts.addOption(Option.builder("k").longOpt("key").desc("Use keyPair from file [key_file] (wx,wy,s).").hasArg().argName("key_file").build());
         opts.addOption(Option.builder("o").longOpt("output").desc("Output into file [output_file].").hasArg().argName("output_file").build());
         opts.addOption(Option.builder("l").longOpt("log").desc("Log output into file [log_file].").hasArg().argName("log_file").optionalArg(true).build());
         opts.addOption(Option.builder("s").longOpt("simulate").desc("Simulate a card with jcardsim instead of using a terminal.").build());
@@ -301,6 +331,19 @@ public class ECTester {
             }
 
         } else if (cli.hasOption("ecdsa")) {
+            if (optPrimeField == optBinaryField) {
+                System.err.print("Need to specify field with -fp or -f2m. (not both)");
+                return false;
+            }
+            if (optAll) {
+                System.err.println("You have to specify curve bit-size with -b");
+                return false;
+            }
+            if ((optPublic == null) != (optPrivate == null)) {
+                System.err.println("You have cannot only specify a part of a keypair.");
+                return false;
+            }
+
             optECDSASign = cli.getOptionValue("ecdsa");
         }
 
@@ -316,9 +359,10 @@ public class ECTester {
     }
 
     /**
-     * Generates EC keypairs and outputs them to output file.
-     * @throws CardException
-     * @throws IOException
+     * Generates EC keyPairs and outputs them to output file.
+     *
+     * @throws CardException if APDU transmission fails
+     * @throws IOException   if an IO error occurs when writing to key file.
      */
     private void generate() throws CardException, IOException {
         byte keyClass = optPrimeField ? KeyPair.ALG_EC_FP : KeyPair.ALG_EC_F2M;
@@ -360,9 +404,10 @@ public class ECTester {
     }
 
     /**
-     * Tests
+     * Tests Elliptic curve support for a given curve/curves.
      */
     private void test() {
+        //TODO
         if (optAll) {
             if (optPrimeField) {
                 //iterate over prime curve sizes used: EC_Consts.FP_SIZES
@@ -404,9 +449,10 @@ public class ECTester {
     }
 
     /**
+     * Performs ECDH key exchange.
      *
-     * @throws IOException
-     * @throws CardException
+     * @throws CardException if APDU transmission fails
+     * @throws IOException   if an IO error occurs when writing to key file.
      */
     private void ecdh() throws IOException, CardException {
         byte keyClass = optPrimeField ? KeyPair.ALG_EC_FP : KeyPair.ALG_EC_F2M;
@@ -425,24 +471,55 @@ public class ECTester {
 
         CommandAPDU ecdh = insECDH(ECTesterApplet.KEYPAIR_LOCAL, ECTesterApplet.KEYPAIR_REMOTE, ECTesterApplet.EXPORT_ECDH, (byte) 0);
         ResponseAPDU response = cardManager.send(ecdh);
-        //TODO output ecdh
+        //TODO print response SWs/error codes
+        //TODO output to file
     }
 
     /**
+     * Performs ECDSA signature, on random or provided data.
+     *
+     * @throws CardException if APDU transmission fails
+     * @throws IOException   if an IO error occurs when writing to key file.
      */
-    private void ecdsa() {
-        //TODO
+    private void ecdsa() throws CardException, IOException {
+        byte keyClass = optPrimeField ? KeyPair.ALG_EC_FP : KeyPair.ALG_EC_F2M;
+        CommandAPDU[] curve = prepareCurve(ECTesterApplet.KEYPAIR_LOCAL, (short) optBits, keyClass);
+        cardManager.send(curve);
+
+        if (optKey != null || (optPublic != null && optPrivate != null)) {
+            CommandAPDU set = prepareKey(ECTesterApplet.KEYPAIR_LOCAL);
+            cardManager.send(set);
+        } else {
+            CommandAPDU generate = insGenerate(ECTesterApplet.KEYPAIR_LOCAL, ECTesterApplet.EXPORT_NONE);
+            cardManager.send(generate);
+        }
+
+        //read file, if asked to sign
+        byte[] data = null;
+        if (optECDSASign != null) {
+            File in = new File(optECDSASign);
+            long len = in.length();
+            if (len == 0) {
+                throw new FileNotFoundException("File " + optECDSASign + " not found.");
+            }
+            data = Files.readAllBytes(in.toPath());
+        }
+
+        CommandAPDU ecdsa = insECDSA(ECTesterApplet.KEYPAIR_LOCAL, ECTesterApplet.EXPORT_SIG, data);
+        ResponseAPDU response = cardManager.send(ecdsa);
+        //TODO print response SWs/error codes
+        //TODO output to file
     }
 
     /**
      * Creates the INS_ALLOCATE instruction.
      *
-     * @param keyPair
-     * @param keyLength
-     * @param keyClass
+     * @param keyPair   which keyPair to use, local/remote (KEYPAIR_* | ...)
+     * @param keyLength key length to set
+     * @param keyClass  key class to allocate
      * @return apdu to send
      */
-    private CommandAPDU insAllocate(byte keyPair, short keyLength, byte keyClass) throws CardException {
+    private CommandAPDU insAllocate(byte keyPair, short keyLength, byte keyClass) {
         byte[] data = new byte[]{0, 0, keyClass};
         Util.setShort(data, 0, keyLength);
 
@@ -452,13 +529,13 @@ public class ECTester {
     /**
      * Creates the INS_SET instruction.
      *
-     * @param keyPair
-     * @param export
-     * @param curve
-     * @param params
-     * @param corrupted
-     * @param corruption
-     * @param external
+     * @param keyPair    which keyPair to set params on, local/remote (KEYPAIR_* || ...)
+     * @param export     whether to export set params from keyPair
+     * @param curve      curve to set (EC_Consts.CURVE_*)
+     * @param params     parameters to set (EC_Consts.PARAMETER_* | ...)
+     * @param corrupted  parameters to corrupt (EC_Consts.PARAMETER_* | ...)
+     * @param corruption corruption type (EC_Consts.CORRUPTION_*)
+     * @param external   external curve data, can be null
      * @return apdu to send
      */
     private CommandAPDU insSet(byte keyPair, byte export, byte curve, short params, short corrupted, byte corruption, byte[] external) {
@@ -478,8 +555,8 @@ public class ECTester {
     /**
      * Creates the INS_GENERATE instruction.
      *
-     * @param keyPair
-     * @param export
+     * @param keyPair which keyPair to generate, local/remote (KEYPAIR_* || ...)
+     * @param export  whether to export generated keys from keyPair
      * @return apdu to send
      */
     private CommandAPDU insGenerate(byte keyPair, byte export) {
@@ -489,10 +566,10 @@ public class ECTester {
     /**
      * Creates the INS_ECDH instruction.
      *
-     * @param pubkey
-     * @param privkey
-     * @param export
-     * @param invalid
+     * @param pubkey  keyPair to use for public key, (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
+     * @param privkey keyPair to use for private key, (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
+     * @param export  whether to export ECDH secret
+     * @param invalid whether to invalidate the pubkey before ECDH
      * @return apdu to send
      */
     private CommandAPDU insECDH(byte pubkey, byte privkey, byte export, byte invalid) {
@@ -504,9 +581,9 @@ public class ECTester {
     /**
      * Creates the INS_ECDSA instruction.
      *
-     * @param keyPair
-     * @param export
-     * @param raw
+     * @param keyPair keyPair to use for signing and verification (KEYPAIR_LOCAL || KEYPAIR_REMOTE)
+     * @param export  whether to export ECDSA signature
+     * @param raw     data to sign, can be null, in which case random data is signed.
      * @return apdu to send
      */
     private CommandAPDU insECDSA(byte keyPair, byte export, byte[] raw) {
@@ -521,14 +598,13 @@ public class ECTester {
     }
 
     /**
-     * @param keyPair
-     * @param keyLength
-     * @param keyClass
-     * @return
-     * @throws CardException
-     * @throws FileNotFoundException
+     * @param keyPair   which keyPair/s (local/remote) to set curve domain parameters on
+     * @param keyLength key length to allocate
+     * @param keyClass  key class to allocate
+     * @return an array of CommandAPDUs to send in order to prepare the keypair/s.
+     * @throws IOException if curve file cannot be found/opened
      */
-    private CommandAPDU[] prepareCurve(byte keyPair, short keyLength, byte keyClass) throws CardException, IOException {
+    private CommandAPDU[] prepareCurve(byte keyPair, short keyLength, byte keyClass) throws IOException {
         List<CommandAPDU> commands = new ArrayList<>();
         commands.add(insAllocate(keyPair, keyLength, keyClass));
 
@@ -548,11 +624,11 @@ public class ECTester {
     }
 
     /**
-     * @param keypair
-     * @return
-     * @throws IOException
+     * @param keyPair which keyPair/s to set the key params on
+     * @return a CommandAPDU setting params loaded on the keyPair/s
+     * @throws IOException if any of the key files cannot be found/opened
      */
-    private CommandAPDU prepareKey(byte keypair) throws IOException {
+    private CommandAPDU prepareKey(byte keyPair) throws IOException {
         short params = EC_Consts.PARAMETERS_NONE;
         byte[] data = null;
         if (optKey != null) {
@@ -570,9 +646,13 @@ public class ECTester {
         }
 
         if (data == null && params != EC_Consts.PARAMETERS_NONE) {
+            /*
+            TODO: this is not correct, in case (optPublic != null) and (optPrivate != null),
+            only one can actually load(return not null from ParamReader.flatten) and an exception will not be thrown
+             */
             throw new IOException("Couldn't read the key file correctly.");
         }
-        return insSet(keypair, ECTesterApplet.EXPORT_NONE, EC_Consts.CURVE_external, params, EC_Consts.PARAMETERS_NONE, EC_Consts.CORRUPTION_NONE, data);
+        return insSet(keyPair, ECTesterApplet.EXPORT_NONE, EC_Consts.CURVE_external, params, EC_Consts.PARAMETERS_NONE, EC_Consts.CORRUPTION_NONE, data);
     }
 
     public static void main(String[] args) {
diff --git a/src/cz/crcs/ectester/reader/ParamReader.java b/src/cz/crcs/ectester/reader/ParamReader.java
index 5232326..ca14d2d 100644
--- a/src/cz/crcs/ectester/reader/ParamReader.java
+++ b/src/cz/crcs/ectester/reader/ParamReader.java
@@ -9,6 +9,7 @@ import java.util.Scanner;
 import java.util.regex.Pattern;
 
 /**
+ *
  * @author Jan Jancar johny@neuromancer.sk
  */
 public class ParamReader {
@@ -18,7 +19,7 @@ public class ParamReader {
      * Flattens params read from String[] data into a byte[] with their lengths prepended as short entries.
      * @param params (EC_Consts.PARAMETER_* | ...)
      * @param data data read by readString, readFile, readResource
-     * @return byte[] with params flattened
+     * @return byte[] with params flattened, or null
      */
     public static byte[] flatten(short params, String[] data) {
         if (!validate(data)) {
@@ -42,7 +43,7 @@ public class ParamReader {
                 if (masked == EC_Consts.PARAMETER_G || masked == EC_Consts.PARAMETER_W) {
                     //read another param (the y coord) and put into X962 format.
                     byte[] y = parse(data[i + 1]);
-                    param = Util.concatenate(new byte[]{4}, param, y);
+                    param = Util.concatenate(new byte[]{4}, param, y);//<- ugly but works!
                     i++;
                 }
                 if (param.length == 0)
diff --git a/src/cz/crcs/ectester/reader/Util.java b/src/cz/crcs/ectester/reader/Util.java
index aa0dfd5..1464728 100644
--- a/src/cz/crcs/ectester/reader/Util.java
+++ b/src/cz/crcs/ectester/reader/Util.java
@@ -1,6 +1,12 @@
 package cz.crcs.ectester.reader;
 
+import cz.crcs.ectester.applet.ECTesterApplet;
+import javacard.framework.ISO7816;
+import javacard.security.CryptoException;
+
 /**
+ * Utility class, some byte/hex manipulation, convenient byte[] methods.
+ *
  * @author Petr Svenda petr@svenda.com
  * @author Jan Jancar johny@neuromancer.sk
  */
@@ -79,4 +85,33 @@ public class Util {
         }
         return out;
     }
+
+    public static String getPrintError(short code) {
+        if (code == ISO7816.SW_NO_ERROR) {
+            return "OK\t(0x9000)";
+        } else {
+            String codeStr = "unknown";
+            switch (code) {
+                case CryptoException.ILLEGAL_VALUE:
+                    codeStr = "ILLEGAL_VALUE";
+                    break;
+                case CryptoException.UNINITIALIZED_KEY:
+                    codeStr = "UNINITIALIZED_KEY";
+                    break;
+                case CryptoException.NO_SUCH_ALGORITHM:
+                    codeStr = "NO_SUCH_ALG";
+                    break;
+                case CryptoException.INVALID_INIT:
+                    codeStr = "INVALID_INIT";
+                    break;
+                case CryptoException.ILLEGAL_USE:
+                    codeStr = "ILLEGAL_USE";
+                    break;
+                case ECTesterApplet.SW_SIG_VERIFY_FAIL:
+                    codeStr = "SIG_VERIFY_FAIL";
+                    break;
+            }
+            return String.format("fail\t(%s,\t0x%4x)", codeStr, code);
+        }
+    }
 }