diff options
Diffstat (limited to 'OpenPGP-Keychain/src/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java')
| -rw-r--r-- | OpenPGP-Keychain/src/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java | 457 |
1 files changed, 457 insertions, 0 deletions
diff --git a/OpenPGP-Keychain/src/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java b/OpenPGP-Keychain/src/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java new file mode 100644 index 000000000..1ef5060ca --- /dev/null +++ b/OpenPGP-Keychain/src/org/sufficientlysecure/keychain/pgp/PgpKeyOperation.java @@ -0,0 +1,457 @@ +/* + * Copyright (C) 2012-2013 Dominik Schürmann <dominik@dominikschuermann.de> + * Copyright (C) 2010 Thialfihar <thi@thialfihar.org> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.sufficientlysecure.keychain.pgp; + +import java.io.IOException; +import java.math.BigInteger; +import java.security.InvalidAlgorithmParameterException; +import java.security.KeyPairGenerator; +import java.security.NoSuchAlgorithmException; +import java.security.NoSuchProviderException; +import java.security.SecureRandom; +import java.security.SignatureException; +import java.util.ArrayList; +import java.util.Date; + +import org.spongycastle.bcpg.CompressionAlgorithmTags; +import org.spongycastle.bcpg.HashAlgorithmTags; +import org.spongycastle.bcpg.SymmetricKeyAlgorithmTags; +import org.spongycastle.bcpg.sig.KeyFlags; +import org.spongycastle.jce.provider.BouncyCastleProvider; +import org.spongycastle.jce.spec.ElGamalParameterSpec; +import org.spongycastle.openpgp.PGPEncryptedData; +import org.spongycastle.openpgp.PGPException; +import org.spongycastle.openpgp.PGPKeyPair; +import org.spongycastle.openpgp.PGPKeyRingGenerator; +import org.spongycastle.openpgp.PGPPrivateKey; +import org.spongycastle.openpgp.PGPPublicKey; +import org.spongycastle.openpgp.PGPPublicKeyRing; +import org.spongycastle.openpgp.PGPSecretKey; +import org.spongycastle.openpgp.PGPSecretKeyRing; +import org.spongycastle.openpgp.PGPSignature; +import org.spongycastle.openpgp.PGPSignatureGenerator; +import org.spongycastle.openpgp.PGPSignatureSubpacketGenerator; +import org.spongycastle.openpgp.PGPSignatureSubpacketVector; +import org.spongycastle.openpgp.PGPUtil; +import org.spongycastle.openpgp.operator.PBESecretKeyDecryptor; +import org.spongycastle.openpgp.operator.PBESecretKeyEncryptor; +import org.spongycastle.openpgp.operator.PGPContentSignerBuilder; +import org.spongycastle.openpgp.operator.PGPDigestCalculator; +import org.spongycastle.openpgp.operator.jcajce.JcaPGPContentSignerBuilder; +import org.spongycastle.openpgp.operator.jcajce.JcaPGPDigestCalculatorProviderBuilder; +import org.spongycastle.openpgp.operator.jcajce.JcaPGPKeyPair; +import org.spongycastle.openpgp.operator.jcajce.JcePBESecretKeyDecryptorBuilder; +import org.spongycastle.openpgp.operator.jcajce.JcePBESecretKeyEncryptorBuilder; +import org.sufficientlysecure.keychain.Constants; +import org.sufficientlysecure.keychain.Id; +import org.sufficientlysecure.keychain.R; +import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException; +import org.sufficientlysecure.keychain.provider.ProviderHelper; +import org.sufficientlysecure.keychain.util.Log; +import org.sufficientlysecure.keychain.util.Primes; +import org.sufficientlysecure.keychain.util.ProgressDialogUpdater; + +import android.content.Context; + +public class PgpKeyOperation { + private Context mContext; + private ProgressDialogUpdater mProgress; + + private static final int[] PREFERRED_SYMMETRIC_ALGORITHMS = new int[] { + SymmetricKeyAlgorithmTags.AES_256, SymmetricKeyAlgorithmTags.AES_192, + SymmetricKeyAlgorithmTags.AES_128, SymmetricKeyAlgorithmTags.CAST5, + SymmetricKeyAlgorithmTags.TRIPLE_DES }; + private static final int[] PREFERRED_HASH_ALGORITHMS = new int[] { HashAlgorithmTags.SHA1, + HashAlgorithmTags.SHA256, HashAlgorithmTags.RIPEMD160 }; + private static final int[] PREFERRED_COMPRESSION_ALGORITHMS = new int[] { + CompressionAlgorithmTags.ZLIB, CompressionAlgorithmTags.BZIP2, + CompressionAlgorithmTags.ZIP }; + + public PgpKeyOperation(Context context, ProgressDialogUpdater progress) { + super(); + this.mContext = context; + this.mProgress = progress; + } + + public void updateProgress(int message, int current, int total) { + if (mProgress != null) { + mProgress.setProgress(message, current, total); + } + } + + public void updateProgress(int current, int total) { + if (mProgress != null) { + mProgress.setProgress(current, total); + } + } + + /** + * Creates new secret key. The returned PGPSecretKeyRing contains only one newly generated key + * when this key is the new masterkey. If a masterkey is supplied in the parameters + * PGPSecretKeyRing contains the masterkey and the new key as a subkey (certified by the + * masterkey). + * + * @param context + * @param algorithmChoice + * @param keySize + * @param passPhrase + * @param masterSecretKey + * @return + * @throws NoSuchAlgorithmException + * @throws PGPException + * @throws NoSuchProviderException + * @throws PgpGeneralException + * @throws InvalidAlgorithmParameterException + */ + public PGPSecretKeyRing createKey(int algorithmChoice, int keySize, String passPhrase, + PGPSecretKey masterSecretKey) throws NoSuchAlgorithmException, PGPException, + NoSuchProviderException, PgpGeneralException, InvalidAlgorithmParameterException { + + if (keySize < 512) { + throw new PgpGeneralException(mContext.getString(R.string.error_keySizeMinimum512bit)); + } + + if (passPhrase == null) { + passPhrase = ""; + } + + int algorithm = 0; + KeyPairGenerator keyGen = null; + + switch (algorithmChoice) { + case Id.choice.algorithm.dsa: { + keyGen = KeyPairGenerator.getInstance("DSA", Constants.BOUNCY_CASTLE_PROVIDER_NAME); + keyGen.initialize(keySize, new SecureRandom()); + algorithm = PGPPublicKey.DSA; + break; + } + + case Id.choice.algorithm.elgamal: { + if (masterSecretKey == null) { + throw new PgpGeneralException( + mContext.getString(R.string.error_masterKeyMustNotBeElGamal)); + } + keyGen = KeyPairGenerator.getInstance("ElGamal", Constants.BOUNCY_CASTLE_PROVIDER_NAME); + BigInteger p = Primes.getBestPrime(keySize); + BigInteger g = new BigInteger("2"); + + ElGamalParameterSpec elParams = new ElGamalParameterSpec(p, g); + + keyGen.initialize(elParams); + algorithm = PGPPublicKey.ELGAMAL_ENCRYPT; + break; + } + + case Id.choice.algorithm.rsa: { + keyGen = KeyPairGenerator.getInstance("RSA", Constants.BOUNCY_CASTLE_PROVIDER_NAME); + keyGen.initialize(keySize, new SecureRandom()); + + algorithm = PGPPublicKey.RSA_GENERAL; + break; + } + + default: { + throw new PgpGeneralException(mContext.getString(R.string.error_unknownAlgorithmChoice)); + } + } + + // build new key pair + PGPKeyPair keyPair = new JcaPGPKeyPair(algorithm, keyGen.generateKeyPair(), new Date()); + + // define hashing and signing algos + PGPDigestCalculator sha1Calc = new JcaPGPDigestCalculatorProviderBuilder().build().get( + HashAlgorithmTags.SHA1); + + // Build key encrypter and decrypter based on passphrase + PBESecretKeyEncryptor keyEncryptor = new JcePBESecretKeyEncryptorBuilder( + PGPEncryptedData.CAST5, sha1Calc) + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(passPhrase.toCharArray()); + PBESecretKeyDecryptor keyDecryptor = new JcePBESecretKeyDecryptorBuilder().setProvider( + Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(passPhrase.toCharArray()); + + PGPKeyRingGenerator ringGen = null; + PGPContentSignerBuilder certificationSignerBuilder = null; + if (masterSecretKey == null) { + certificationSignerBuilder = new JcaPGPContentSignerBuilder(keyPair.getPublicKey() + .getAlgorithm(), HashAlgorithmTags.SHA1); + + // build keyRing with only this one master key in it! + ringGen = new PGPKeyRingGenerator(PGPSignature.POSITIVE_CERTIFICATION, keyPair, "", + sha1Calc, null, null, certificationSignerBuilder, keyEncryptor); + } else { + PGPPublicKey masterPublicKey = masterSecretKey.getPublicKey(); + PGPPrivateKey masterPrivateKey = masterSecretKey.extractPrivateKey(keyDecryptor); + PGPKeyPair masterKeyPair = new PGPKeyPair(masterPublicKey, masterPrivateKey); + + certificationSignerBuilder = new JcaPGPContentSignerBuilder(masterKeyPair + .getPublicKey().getAlgorithm(), HashAlgorithmTags.SHA1); + + // build keyRing with master key and new key as subkey (certified by masterkey) + ringGen = new PGPKeyRingGenerator(PGPSignature.POSITIVE_CERTIFICATION, masterKeyPair, + "", sha1Calc, null, null, certificationSignerBuilder, keyEncryptor); + + ringGen.addSubKey(keyPair); + } + + PGPSecretKeyRing secKeyRing = ringGen.generateSecretKeyRing(); + + return secKeyRing; + } + + public void changeSecretKeyPassphrase(PGPSecretKeyRing keyRing, String oldPassPhrase, + String newPassPhrase) throws IOException, PGPException, PGPException, + NoSuchProviderException { + + updateProgress(R.string.progress_buildingKey, 0, 100); + if (oldPassPhrase == null) { + oldPassPhrase = ""; + } + if (newPassPhrase == null) { + newPassPhrase = ""; + } + + PGPSecretKeyRing newKeyRing = PGPSecretKeyRing.copyWithNewPassword( + keyRing, + new JcePBESecretKeyDecryptorBuilder(new JcaPGPDigestCalculatorProviderBuilder() + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build()).setProvider( + Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(oldPassPhrase.toCharArray()), + new JcePBESecretKeyEncryptorBuilder(keyRing.getSecretKey() + .getKeyEncryptionAlgorithm()).build(newPassPhrase.toCharArray())); + + updateProgress(R.string.progress_savingKeyRing, 50, 100); + + ProviderHelper.saveKeyRing(mContext, newKeyRing); + + updateProgress(R.string.progress_done, 100, 100); + + } + + public void buildSecretKey(ArrayList<String> userIds, ArrayList<PGPSecretKey> keys, + ArrayList<Integer> keysUsages, long masterKeyId, String oldPassPhrase, + String newPassPhrase) throws PgpGeneralException, NoSuchProviderException, + PGPException, NoSuchAlgorithmException, SignatureException, IOException { + + Log.d(Constants.TAG, "userIds: " + userIds.toString()); + + updateProgress(R.string.progress_buildingKey, 0, 100); + + if (oldPassPhrase == null) { + oldPassPhrase = ""; + } + if (newPassPhrase == null) { + newPassPhrase = ""; + } + + updateProgress(R.string.progress_preparingMasterKey, 10, 100); + + int usageId = keysUsages.get(0); + boolean canSign = (usageId == Id.choice.usage.sign_only || usageId == Id.choice.usage.sign_and_encrypt); + boolean canEncrypt = (usageId == Id.choice.usage.encrypt_only || usageId == Id.choice.usage.sign_and_encrypt); + + String mainUserId = userIds.get(0); + + PGPSecretKey masterKey = keys.get(0); + + // this removes all userIds and certifications previously attached to the masterPublicKey + PGPPublicKey tmpKey = masterKey.getPublicKey(); + PGPPublicKey masterPublicKey = new PGPPublicKey(tmpKey.getAlgorithm(), + tmpKey.getKey(new BouncyCastleProvider()), tmpKey.getCreationTime()); + + // already done by code above: + // PGPPublicKey masterPublicKey = masterKey.getPublicKey(); + // // Somehow, the PGPPublicKey already has an empty certification attached to it when the + // // keyRing is generated the first time, we remove that when it exists, before adding the + // new + // // ones + // PGPPublicKey masterPublicKeyRmCert = PGPPublicKey.removeCertification(masterPublicKey, + // ""); + // if (masterPublicKeyRmCert != null) { + // masterPublicKey = masterPublicKeyRmCert; + // } + + PBESecretKeyDecryptor keyDecryptor = new JcePBESecretKeyDecryptorBuilder().setProvider( + Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(oldPassPhrase.toCharArray()); + PGPPrivateKey masterPrivateKey = masterKey.extractPrivateKey(keyDecryptor); + + updateProgress(R.string.progress_certifyingMasterKey, 20, 100); + + for (String userId : userIds) { + PGPContentSignerBuilder signerBuilder = new JcaPGPContentSignerBuilder( + masterPublicKey.getAlgorithm(), HashAlgorithmTags.SHA1) + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME); + PGPSignatureGenerator sGen = new PGPSignatureGenerator(signerBuilder); + + sGen.init(PGPSignature.POSITIVE_CERTIFICATION, masterPrivateKey); + + PGPSignature certification = sGen.generateCertification(userId, masterPublicKey); + + masterPublicKey = PGPPublicKey.addCertification(masterPublicKey, userId, certification); + } + + // TODO: cross-certify the master key with every sub key (APG 1) + + PGPKeyPair masterKeyPair = new PGPKeyPair(masterPublicKey, masterPrivateKey); + + PGPSignatureSubpacketGenerator hashedPacketsGen = new PGPSignatureSubpacketGenerator(); + PGPSignatureSubpacketGenerator unhashedPacketsGen = new PGPSignatureSubpacketGenerator(); + + int keyFlags = KeyFlags.CERTIFY_OTHER | KeyFlags.SIGN_DATA; + if (canEncrypt) { + keyFlags |= KeyFlags.ENCRYPT_COMMS | KeyFlags.ENCRYPT_STORAGE; + } + hashedPacketsGen.setKeyFlags(true, keyFlags); + + hashedPacketsGen.setPreferredSymmetricAlgorithms(true, PREFERRED_SYMMETRIC_ALGORITHMS); + hashedPacketsGen.setPreferredHashAlgorithms(true, PREFERRED_HASH_ALGORITHMS); + hashedPacketsGen.setPreferredCompressionAlgorithms(true, PREFERRED_COMPRESSION_ALGORITHMS); + + // TODO: this doesn't work quite right yet (APG 1) + // if (keyEditor.getExpiryDate() != null) { + // GregorianCalendar creationDate = new GregorianCalendar(); + // creationDate.setTime(getCreationDate(masterKey)); + // GregorianCalendar expiryDate = keyEditor.getExpiryDate(); + // long numDays = Utils.getNumDaysBetween(creationDate, expiryDate); + // if (numDays <= 0) { + // throw new GeneralException( + // context.getString(R.string.error_expiryMustComeAfterCreation)); + // } + // hashedPacketsGen.setKeyExpirationTime(true, numDays * 86400); + // } + + updateProgress(R.string.progress_buildingMasterKeyRing, 30, 100); + + // define hashing and signing algos + PGPDigestCalculator sha1Calc = new JcaPGPDigestCalculatorProviderBuilder().build().get( + HashAlgorithmTags.SHA1); + PGPContentSignerBuilder certificationSignerBuilder = new JcaPGPContentSignerBuilder( + masterKeyPair.getPublicKey().getAlgorithm(), HashAlgorithmTags.SHA1); + + // Build key encrypter based on passphrase + PBESecretKeyEncryptor keyEncryptor = new JcePBESecretKeyEncryptorBuilder( + PGPEncryptedData.CAST5, sha1Calc) + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build( + newPassPhrase.toCharArray()); + + PGPKeyRingGenerator keyGen = new PGPKeyRingGenerator(PGPSignature.POSITIVE_CERTIFICATION, + masterKeyPair, mainUserId, sha1Calc, hashedPacketsGen.generate(), + unhashedPacketsGen.generate(), certificationSignerBuilder, keyEncryptor); + + updateProgress(R.string.progress_addingSubKeys, 40, 100); + + for (int i = 1; i < keys.size(); ++i) { + updateProgress(40 + 50 * (i - 1) / (keys.size() - 1), 100); + + PGPSecretKey subKey = keys.get(i); + PGPPublicKey subPublicKey = subKey.getPublicKey(); + + PBESecretKeyDecryptor keyDecryptor2 = new JcePBESecretKeyDecryptorBuilder() + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME).build( + oldPassPhrase.toCharArray()); + PGPPrivateKey subPrivateKey = subKey.extractPrivateKey(keyDecryptor2); + + // TODO: now used without algorithm and creation time?! (APG 1) + PGPKeyPair subKeyPair = new PGPKeyPair(subPublicKey, subPrivateKey); + + hashedPacketsGen = new PGPSignatureSubpacketGenerator(); + unhashedPacketsGen = new PGPSignatureSubpacketGenerator(); + + keyFlags = 0; + + usageId = keysUsages.get(i); + canSign = (usageId == Id.choice.usage.sign_only || usageId == Id.choice.usage.sign_and_encrypt); + canEncrypt = (usageId == Id.choice.usage.encrypt_only || usageId == Id.choice.usage.sign_and_encrypt); + if (canSign) { + keyFlags |= KeyFlags.SIGN_DATA; + } + if (canEncrypt) { + keyFlags |= KeyFlags.ENCRYPT_COMMS | KeyFlags.ENCRYPT_STORAGE; + } + hashedPacketsGen.setKeyFlags(true, keyFlags); + + // TODO: this doesn't work quite right yet (APG 1) + // if (keyEditor.getExpiryDate() != null) { + // GregorianCalendar creationDate = new GregorianCalendar(); + // creationDate.setTime(getCreationDate(masterKey)); + // GregorianCalendar expiryDate = keyEditor.getExpiryDate(); + // long numDays = Utils.getNumDaysBetween(creationDate, expiryDate); + // if (numDays <= 0) { + // throw new GeneralException( + // context.getString(R.string.error_expiryMustComeAfterCreation)); + // } + // hashedPacketsGen.setKeyExpirationTime(true, numDays * 86400); + // } + + keyGen.addSubKey(subKeyPair, hashedPacketsGen.generate(), unhashedPacketsGen.generate()); + } + + PGPSecretKeyRing secretKeyRing = keyGen.generateSecretKeyRing(); + PGPPublicKeyRing publicKeyRing = keyGen.generatePublicKeyRing(); + + updateProgress(R.string.progress_savingKeyRing, 90, 100); + + ProviderHelper.saveKeyRing(mContext, secretKeyRing); + ProviderHelper.saveKeyRing(mContext, publicKeyRing); + + updateProgress(R.string.progress_done, 100, 100); + } + + public PGPPublicKeyRing signKey(long masterKeyId, long pubKeyId, String passphrase) + throws PgpGeneralException, NoSuchAlgorithmException, NoSuchProviderException, + PGPException, SignatureException { + if (passphrase == null || passphrase.length() <= 0) { + throw new PgpGeneralException("Unable to obtain passphrase"); + } else { + PGPPublicKeyRing pubring = ProviderHelper + .getPGPPublicKeyRingByKeyId(mContext, pubKeyId); + + PGPSecretKey signingKey = PgpKeyHelper.getCertificationKey(mContext, masterKeyId); + if (signingKey == null) { + throw new PgpGeneralException(mContext.getString(R.string.error_signatureFailed)); + } + + PBESecretKeyDecryptor keyDecryptor = new JcePBESecretKeyDecryptorBuilder().setProvider( + Constants.BOUNCY_CASTLE_PROVIDER_NAME).build(passphrase.toCharArray()); + PGPPrivateKey signaturePrivateKey = signingKey.extractPrivateKey(keyDecryptor); + if (signaturePrivateKey == null) { + throw new PgpGeneralException( + mContext.getString(R.string.error_couldNotExtractPrivateKey)); + } + + // TODO: SHA256 fixed? + JcaPGPContentSignerBuilder contentSignerBuilder = new JcaPGPContentSignerBuilder( + signingKey.getPublicKey().getAlgorithm(), PGPUtil.SHA256) + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME); + + PGPSignatureGenerator signatureGenerator = new PGPSignatureGenerator( + contentSignerBuilder); + + signatureGenerator.init(PGPSignature.DIRECT_KEY, signaturePrivateKey); + + PGPSignatureSubpacketGenerator spGen = new PGPSignatureSubpacketGenerator(); + + PGPSignatureSubpacketVector packetVector = spGen.generate(); + signatureGenerator.setHashedSubpackets(packetVector); + + PGPPublicKey signedKey = PGPPublicKey.addCertification(pubring.getPublicKey(pubKeyId), + signatureGenerator.generate()); + pubring = PGPPublicKeyRing.insertPublicKey(pubring, signedKey); + + return pubring; + } + } +} |