Improved smart card error handling

This commit is contained in:
Joey Castillo 2015-06-10 17:13:14 -04:00
parent 7a5121894e
commit 14226461c1
3 changed files with 168 additions and 23 deletions

View File

@ -10,7 +10,6 @@ import android.content.Intent;
import android.os.Bundle;
import android.view.WindowManager;
import org.spongycastle.util.Arrays;
import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.R;
import org.sufficientlysecure.keychain.pgp.CanonicalizedSecretKey;
@ -28,6 +27,7 @@ import org.sufficientlysecure.keychain.util.Preferences;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.Arrays;
/**
* This class provides a communication interface to OpenPGP applications on ISO SmartCard compliant
@ -47,6 +47,8 @@ public class NfcOperationActivity extends BaseNfcActivity {
private RequiredInputParcel mRequiredInput;
private Intent mServiceIntent;
private static final byte[] BLANK_FINGERPRINT = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
@ -126,17 +128,29 @@ public class NfcOperationActivity extends BaseNfcActivity {
}
if (key.canSign() || key.canCertify()) {
nfcPutKey(0xB6, key, passphrase);
nfcPutData(0xCE, timestampBytes);
nfcPutData(0xC7, key.getFingerprint());
if (shouldPutKey(key.getFingerprint(), 0)) {
nfcPutKey(0xB6, key, passphrase);
nfcPutData(0xCE, timestampBytes);
nfcPutData(0xC7, key.getFingerprint());
} else {
throw new IOException("Key slot occupied; card must be reset to put new signature key.");
}
} else if (key.canEncrypt()) {
nfcPutKey(0xB8, key, passphrase);
nfcPutData(0xCF, timestampBytes);
nfcPutData(0xC8, key.getFingerprint());
if (shouldPutKey(key.getFingerprint(), 1)) {
nfcPutKey(0xB8, key, passphrase);
nfcPutData(0xCF, timestampBytes);
nfcPutData(0xC8, key.getFingerprint());
} else {
throw new IOException("Key slot occupied; card must be reset to put new decryption key.");
}
} else if (key.canAuthenticate()) {
nfcPutKey(0xA4, key, passphrase);
nfcPutData(0xD0, timestampBytes);
nfcPutData(0xC9, key.getFingerprint());
if (shouldPutKey(key.getFingerprint(), 2)) {
nfcPutKey(0xA4, key, passphrase);
nfcPutData(0xD0, timestampBytes);
nfcPutData(0xC9, key.getFingerprint());
} else {
throw new IOException("Key slot occupied; card must be reset to put new authentication key.");
}
} else {
throw new IOException("Inappropriate key flags for smart card key.");
}
@ -158,6 +172,18 @@ public class NfcOperationActivity extends BaseNfcActivity {
finish();
}
private boolean shouldPutKey(byte[] fingerprint, int idx) throws IOException {
byte[] cardFingerprint = nfcGetFingerprint(idx);
// Slot is empty, or contains this key already. PUT KEY operation is safe
if (Arrays.equals(cardFingerprint, BLANK_FINGERPRINT) ||
Arrays.equals(cardFingerprint, fingerprint)) {
return true;
}
// Slot already contains a different key; don't overwrite it.
return false;
}
@Override
public void handlePinError() {

View File

@ -95,6 +95,8 @@ public abstract class BaseNfcActivity extends BaseActivity {
if (NfcAdapter.ACTION_TAG_DISCOVERED.equals(intent.getAction())) {
try {
handleNdefDiscoveredIntent(intent);
} catch (CardException e) {
handleNfcError(e);
} catch (IOException e) {
handleNfcError(e);
}
@ -105,6 +107,83 @@ public abstract class BaseNfcActivity extends BaseActivity {
Log.e(Constants.TAG, "nfc error", e);
Notify.create(this, getString(R.string.error_nfc, e.getMessage()), Style.WARN).show();
}
public void handleNfcError(CardException e) {
Log.e(Constants.TAG, "card error", e);
short status = e.getResponseCode();
// When entering a PIN, a status of 63CX indicates X attempts remaining.
if ((status & (short)0xFFF0) == 0x63C0) {
Notify.create(this, getString(R.string.error_pin, status & 0x000F), Style.WARN).show();
return;
}
// Otherwise, all status codes are fixed values.
switch (status) {
// These errors should not occur in everyday use; if they are returned, it means we
// made a mistake sending data to the card.
case 0x6A80:
throw new AssertionError("Card returned 'Wrong Data' status; this is a programming error!");
case 0x6883:
throw new AssertionError("Card expected last command in a chain; this is a programming error!");
case 0x6B00:
throw new AssertionError("Card reported invalid P1/P2 parameter; this is a programming error!");
case 0x6D00:
throw new AssertionError("Instruction (INS) not supported by smart card; this is a programming error!");
case 0x6E00:
throw new AssertionError("Class (CLA) not supported by smart card; this is a programming error!");
// These errors might be encountered in everyday use, and should display a localized
// error message to the user.
case 0x6285:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_terminated)), Style.WARN).show();
break;
}
case 0x6700:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_wrong_length)), Style.WARN).show();
break;
}
case 0x6982:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_security_not_satisfied)), Style.WARN).show();
break;
}
case 0x6983:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_authentication_blocked)), Style.WARN).show();
break;
}
case 0x6985:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_conditions_not_satisfied)), Style.WARN).show();
break;
}
case 0x6A88:
case 0x6A83:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_data_not_found)), Style.WARN).show();
break;
}
// 6F00 is a JavaCard proprietary status code, SW_UNKNOWN, and usually represents an
// unhandled exception on the smart card.
case 0x6F00:
{
Notify.create(this, getString(R.string.error_nfc,
getString(R.string.error_nfc_unknown)), Style.WARN).show();
break;
}
default:
Notify.create(this, getString(R.string.error_nfc, e.getMessage()), Style.WARN).show();
}
}
@ -223,8 +302,9 @@ public abstract class BaseNfcActivity extends BaseActivity {
+ "06" // Lc (number of bytes)
+ "D27600012401" // Data (6 bytes)
+ "00"; // Le
if ( ! nfcCommunicate(opening).endsWith(accepted)) { // activate connection
throw new IOException("Initialization failed!");
String response = nfcCommunicate(opening); // activate connection
if ( ! response.endsWith(accepted) ) {
throw new CardException("Initialization failed!", parseCardStatus(response));
}
byte[] pwStatusBytes = nfcGetPwStatusBytes();
@ -439,7 +519,7 @@ public abstract class BaseNfcActivity extends BaseActivity {
}
if ( ! "9000".equals(status)) {
throw new IOException("Bad NFC response code: " + status);
throw new CardException("Bad NFC response code: " + status, parseCardStatus(response));
}
// Make sure the signature we received is actually the expected number of bytes long!
@ -511,9 +591,10 @@ public abstract class BaseNfcActivity extends BaseActivity {
+ String.format("%02x", mode) // P2
+ String.format("%02x", pin.length) // Lc
+ Hex.toHexString(pin);
if (!nfcCommunicate(login).equals(accepted)) { // login
String response = nfcCommunicate(login); // login
if (!response.equals(accepted)) {
handlePinError();
throw new IOException("Bad PIN!");
throw new CardException("Bad PIN!", parseCardStatus(response));
}
if (mode == 0x81) {
@ -567,9 +648,10 @@ public abstract class BaseNfcActivity extends BaseActivity {
+ String.format("%02x", pin.length + newPin.length) // Lc
+ getHex(pin)
+ getHex(newPin);
if (!nfcCommunicate(changeReferenceDataApdu).equals("9000")) { // Change reference data
String response = nfcCommunicate(changeReferenceDataApdu); // change PIN
if (!response.equals("9000")) {
handlePinError();
throw new IOException("Failed to change PIN");
throw new CardException("Failed to change PIN", parseCardStatus(response));
}
}
@ -600,12 +682,9 @@ public abstract class BaseNfcActivity extends BaseActivity {
+ String.format("%02x", data.length) // Lc
+ getHex(data);
String response = nfcCommunicate(putDataApdu);
String response = nfcCommunicate(putDataApdu); // put data
if (!response.equals("9000")) {
throw new IOException("Failed to put data for tag "
+ String.format("%02x", (dataObject & 0xFF00) >> 8)
+ String.format("%02x", dataObject & 0xFF)
+ ": " + response);
throw new CardException("Failed to put data.", parseCardStatus(response));
}
}
@ -713,7 +792,7 @@ public abstract class BaseNfcActivity extends BaseActivity {
}
if (!response.endsWith("9000")) {
throw new IOException("Key export to card failed");
throw new CardException("Key export to card failed", parseCardStatus(response));
}
}
@ -721,6 +800,24 @@ public abstract class BaseNfcActivity extends BaseActivity {
Arrays.fill(dataToSend, (byte) 0);
}
/**
* Parses out the status word from a JavaCard response string.
*
* @param response A hex string with the response from the card
* @return A short indicating the SW1/SW2, or 0 if a status could not be determined.
*/
short parseCardStatus(String response) {
if (response.length() < 4) {
return 0; // invalid input
}
try {
return Short.parseShort(response.substring(response.length() - 4), 16);
} catch (NumberFormatException e) {
return 0;
}
}
/**
* Prints a message to the screen
*
@ -790,4 +887,18 @@ public abstract class BaseNfcActivity extends BaseActivity {
return new String(Hex.encode(raw));
}
public class CardException extends IOException {
private short mResponseCode;
public CardException(String detailMessage, short responseCode) {
super(detailMessage);
mResponseCode = responseCode;
}
public short getResponseCode() {
return mResponseCode;
}
}
}

View File

@ -1309,6 +1309,14 @@
<string name="btn_import">"Import"</string>
<string name="snack_yubi_other">Different key stored on YubiKey!</string>
<string name="error_nfc">"NFC Error: %s"</string>
<string name="error_pin">"Incorrect PIN; %d tries remaining."</string>
<string name="error_nfc_terminated">"Smart card in termination state"</string>
<string name="error_nfc_wrong_length">"Wrong length for sent / received data"</string>
<string name="error_nfc_conditions_not_satisfied">"Conditions of use not satisfied"</string>
<string name="error_nfc_security_not_satisfied">"Security status not satisfied"</string>
<string name="error_nfc_authentication_blocked">"PIN blocked after too many attempts"</string>
<string name="error_nfc_data_not_found">"Key or object not found"</string>
<string name="error_nfc_unknown">"Unknown Error"</string>
<string name="error_pin_nodefault">Default PIN was rejected!</string>
<string name="error_bluetooth_file">Error creating temporary file. Bluetooth sharing will fail.</string>
<string name="snack_encrypt_filenames_on">"Filenames <b>are</b> encrypted."</string>