Work on Yubikey decryption

This commit is contained in:
Dominik Schürmann 2014-09-08 14:04:46 +02:00
parent dc39b58609
commit 518d7116e2
5 changed files with 59 additions and 24 deletions

View File

@ -36,7 +36,7 @@ import org.spongycastle.openpgp.operator.PublicKeyDataDecryptorFactory;
import org.spongycastle.openpgp.operator.jcajce.JcaPGPContentSignerBuilder;
import org.spongycastle.openpgp.operator.jcajce.JcePBESecretKeyDecryptorBuilder;
import org.spongycastle.openpgp.operator.jcajce.JcePublicKeyDataDecryptorFactoryBuilder;
import org.spongycastle.openpgp.operator.jcajce.NfcPublicKeyDataDecryptorFactoryBuilder;
import org.spongycastle.openpgp.operator.jcajce.NfcSyncPublicKeyDataDecryptorFactoryBuilder;
import org.spongycastle.openpgp.operator.jcajce.NfcSyncPGPContentSignerBuilder;
import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException;
@ -82,21 +82,27 @@ public class CanonicalizedSecretKey extends CanonicalizedPublicKey {
}
public enum SecretKeyType {
UNAVAILABLE(0), GNU_DUMMY (1), PASSPHRASE (2), PASSPHRASE_EMPTY (3), DIVERT_TO_CARD (4);
UNAVAILABLE(0), GNU_DUMMY(1), PASSPHRASE(2), PASSPHRASE_EMPTY(3), DIVERT_TO_CARD(4);
final int mNum;
SecretKeyType(int num) {
mNum = num;
}
public static SecretKeyType fromNum(int num) {
switch (num) {
case 1: return GNU_DUMMY;
case 2: return PASSPHRASE;
case 3: return PASSPHRASE_EMPTY;
case 4: return DIVERT_TO_CARD;
case 1:
return GNU_DUMMY;
case 2:
return PASSPHRASE;
case 3:
return PASSPHRASE_EMPTY;
case 4:
return DIVERT_TO_CARD;
// if this case happens, it's probably a check from a database value
default: return UNAVAILABLE;
default:
return UNAVAILABLE;
}
}
@ -250,14 +256,14 @@ public class CanonicalizedSecretKey extends CanonicalizedPublicKey {
}
}
public PublicKeyDataDecryptorFactory getDecryptorFactory() {
public PublicKeyDataDecryptorFactory getDecryptorFactory(byte[] nfcDecryptedSessionKey) {
if (mPrivateKeyState == PRIVATE_KEY_STATE_LOCKED) {
throw new PrivateKeyNotUnlockedException();
}
if (mPrivateKeyState == PRIVATE_KEY_STATE_DIVERT_TO_CARD) {
return new NfcPublicKeyDataDecryptorFactoryBuilder()
.setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(mPrivateKey);
return new NfcSyncPublicKeyDataDecryptorFactoryBuilder()
.setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(nfcDecryptedSessionKey);
} else {
return new JcePublicKeyDataDecryptorFactoryBuilder()
.setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(mPrivateKey);

View File

@ -42,7 +42,7 @@ import org.spongycastle.openpgp.operator.jcajce.JcaKeyFingerprintCalculator;
import org.spongycastle.openpgp.operator.jcajce.JcaPGPContentVerifierBuilderProvider;
import org.spongycastle.openpgp.operator.jcajce.JcaPGPDigestCalculatorProviderBuilder;
import org.spongycastle.openpgp.operator.jcajce.JcePBEDataDecryptorFactoryBuilder;
import org.spongycastle.openpgp.operator.jcajce.NfcPublicKeyDataDecryptorFactoryBuilder;
import org.spongycastle.openpgp.operator.jcajce.NfcSyncPublicKeyDataDecryptorFactoryBuilder;
import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.R;
import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException;
@ -78,6 +78,7 @@ public class PgpDecryptVerify {
private String mPassphrase;
private Set<Long> mAllowedKeyIds;
private boolean mDecryptMetadataOnly;
private byte[] mDecryptedSessionKey;
private PgpDecryptVerify(Builder builder) {
// private Constructor can only be called from Builder
@ -91,6 +92,7 @@ public class PgpDecryptVerify {
this.mPassphrase = builder.mPassphrase;
this.mAllowedKeyIds = builder.mAllowedKeyIds;
this.mDecryptMetadataOnly = builder.mDecryptMetadataOnly;
this.mDecryptedSessionKey = builder.mDecryptedSessionKey;
}
public static class Builder {
@ -106,6 +108,7 @@ public class PgpDecryptVerify {
private String mPassphrase = null;
private Set<Long> mAllowedKeyIds = null;
private boolean mDecryptMetadataOnly = false;
private byte[] mDecryptedSessionKey = null;
public Builder(ProviderHelper providerHelper, PassphraseCache passphraseCache,
InputData data, OutputStream outStream) {
@ -148,6 +151,11 @@ public class PgpDecryptVerify {
return this;
}
public Builder setNfcState(byte[] decryptedSessionKey) {
mDecryptedSessionKey = decryptedSessionKey;
return this;
}
public PgpDecryptVerify build() {
return new PgpDecryptVerify(this);
}
@ -196,10 +204,12 @@ public class PgpDecryptVerify {
}
public static class NeedNfcDataException extends Exception {
public byte[] mDec;
public byte[] mEncryptedSessionKey;
public String mPassphrase;
public NeedNfcDataException(byte[] dec) {
mDec = dec;
public NeedNfcDataException(byte[] encryptedSessionKey, String passphrase) {
mEncryptedSessionKey = encryptedSessionKey;
mPassphrase = passphrase;
}
}
@ -379,11 +389,12 @@ public class PgpDecryptVerify {
currentProgress += 2;
updateProgress(R.string.progress_preparing_streams, currentProgress, 100);
PublicKeyDataDecryptorFactory decryptorFactory = secretEncryptionKey.getDecryptorFactory();
try {
PublicKeyDataDecryptorFactory decryptorFactory
= secretEncryptionKey.getDecryptorFactory(mDecryptedSessionKey);
clear = encryptedDataAsymmetric.getDataStream(decryptorFactory);
} catch (NfcPublicKeyDataDecryptorFactoryBuilder.NfcInteractionNeeded e) {
throw new NeedNfcDataException(e.dec);
} catch (NfcSyncPublicKeyDataDecryptorFactoryBuilder.NfcInteractionNeeded e) {
throw new NeedNfcDataException(e.encryptedSessionKey, mPassphrase);
}
encryptedData = encryptedDataAsymmetric;
} else {

View File

@ -177,7 +177,7 @@ public class OpenPgpService extends RemoteService {
return result;
}
private Intent getNfcDecryptIntent(Intent data, String pin, byte[] dec) {
private Intent getNfcDecryptIntent(Intent data, String pin, byte[] encryptedSessionKey) {
// build PendingIntent for Yubikey NFC operations
Intent intent = new Intent(getBaseContext(), NfcActivity.class);
intent.setAction(NfcActivity.ACTION_DECRYPT_SESSION_KEY);
@ -185,7 +185,7 @@ public class OpenPgpService extends RemoteService {
intent.putExtra(NfcActivity.EXTRA_DATA, data);
intent.putExtra(NfcActivity.EXTRA_PIN, pin);
intent.putExtra(NfcActivity.EXTRA_NFC_DEC, dec);
intent.putExtra(NfcActivity.EXTRA_NFC_ENC_SESSION_KEY, encryptedSessionKey);
intent.addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP | Intent.FLAG_ACTIVITY_CLEAR_TOP);
PendingIntent pi = PendingIntent.getActivity(getBaseContext(), 0,
intent,
@ -432,7 +432,6 @@ public class OpenPgpService extends RemoteService {
Intent result = new Intent();
try {
String passphrase = data.getStringExtra(OpenPgpApi.EXTRA_PASSPHRASE);
long inputLength = is.available();
InputData inputData = new InputData(is, inputLength);
@ -453,12 +452,15 @@ public class OpenPgpService extends RemoteService {
inputData, os
);
byte[] nfcDecryptedSessionKey = data.getByteArrayExtra(OpenPgpApi.EXTRA_NFC_DECRYPTED_SESSION_KEY);
// allow only private keys associated with accounts of this app
// no support for symmetric encryption
builder.setPassphrase(passphrase)
.setAllowSymmetricDecryption(false)
.setAllowedKeyIds(allowedKeyIds)
.setDecryptMetadataOnly(decryptMetadataOnly);
.setDecryptMetadataOnly(decryptMetadataOnly)
.setNfcState(nfcDecryptedSessionKey);
PgpDecryptVerifyResult decryptVerifyResult;
try {
@ -478,7 +480,7 @@ public class OpenPgpService extends RemoteService {
throw new Exception(getString(R.string.error_integrity_check_failed));
} catch (PgpDecryptVerify.NeedNfcDataException e) {
// return PendingIntent to execute NFC activity
return getNfcDecryptIntent(data, passphrase, e.mDec);
return getNfcDecryptIntent(data, e.mPassphrase, e.mEncryptedSessionKey);
}
if (PgpDecryptVerifyResult.KEY_PASSHRASE_NEEDED == decryptVerifyResult.getStatus()) {
@ -522,7 +524,6 @@ public class OpenPgpService extends RemoteService {
result.putExtra(OpenPgpApi.RESULT_METADATA, metadata);
}
}
} finally {
is.close();
if (os != null) {

View File

@ -33,12 +33,15 @@ import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.TextView;
import org.openintents.openpgp.util.OpenPgpApi;
import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.R;
import org.sufficientlysecure.keychain.helper.FileHelper;
import org.sufficientlysecure.keychain.pgp.PgpDecryptVerify;
import org.sufficientlysecure.keychain.pgp.PgpDecryptVerifyResult;
import org.sufficientlysecure.keychain.service.KeychainIntentService;
import org.sufficientlysecure.keychain.service.KeychainIntentServiceHandler;
import org.sufficientlysecure.keychain.service.PassphraseCacheService;
import org.sufficientlysecure.keychain.ui.dialog.DeleteFileDialogFragment;
import org.sufficientlysecure.keychain.ui.dialog.PassphraseDialogFragment;
import org.sufficientlysecure.keychain.util.Log;
@ -182,7 +185,20 @@ public class DecryptFileFragment extends DecryptFragment {
returnData.getParcelable(KeychainIntentService.RESULT_DECRYPT_VERIFY_RESULT);
if (PgpDecryptVerifyResult.KEY_PASSHRASE_NEEDED == decryptVerifyResult.getStatus()) {
showPassphraseDialogForFilename(decryptVerifyResult.getKeyIdPassphraseNeeded());
try {
// try to get passphrase from cache...
String passphrase = PassphraseCacheService.getCachedPassphrase(
getActivity(), decryptVerifyResult.getKeyIdPassphraseNeeded());
if (passphrase != null) {
// try again with passphrase from cache
decryptOriginalFilename(passphrase);
} else {
showPassphraseDialogForFilename(decryptVerifyResult.getKeyIdPassphraseNeeded());
}
} catch (PassphraseCacheService.KeyNotFoundException e) {
Log.e(Constants.TAG, "PassphraseCacheService.KeyNotFoundException", e);
}
} else if (PgpDecryptVerifyResult.SYMMETRIC_PASSHRASE_NEEDED ==
decryptVerifyResult.getStatus()) {
showPassphraseDialogForFilename(Constants.key.symmetric);

View File

@ -186,6 +186,7 @@ public class EditKeyFragment extends LoaderFragment implements
mSaveKeyringParcel.mMasterKeyId);
} catch (PassphraseCacheService.KeyNotFoundException e) {
Log.e(Constants.TAG, "Key not found!", e);
Toast.makeText(getActivity(), R.string.error_no_secret_key_found, Toast.LENGTH_SHORT).show();
getActivity().finish();
return;
}