diff options
Diffstat (limited to 'OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp')
-rw-r--r-- | OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerify.java | 162 |
1 files changed, 161 insertions, 1 deletions
diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerify.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerify.java index 4f086c2a6..4161f2928 100644 --- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerify.java +++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/PgpDecryptVerify.java @@ -48,6 +48,7 @@ import org.sufficientlysecure.keychain.Constants; import org.sufficientlysecure.keychain.R; import org.sufficientlysecure.keychain.operations.BaseOperation; import org.sufficientlysecure.keychain.pgp.exception.PgpGeneralException; +import org.sufficientlysecure.keychain.pgp.exception.PgpKeyNotFoundException; import org.sufficientlysecure.keychain.provider.KeychainContract.KeyRings; import org.sufficientlysecure.keychain.provider.ProviderHelper; import org.sufficientlysecure.keychain.operations.results.DecryptVerifyResult; @@ -83,6 +84,8 @@ public class PgpDecryptVerify extends BaseOperation { private Set<Long> mAllowedKeyIds; private boolean mDecryptMetadataOnly; private byte[] mDecryptedSessionKey; + private String mRequiredSignerFingerprint; + private boolean mSignedLiteralData; private PgpDecryptVerify(Builder builder) { super(builder.mContext, builder.mProviderHelper, builder.mProgressable); @@ -96,6 +99,8 @@ public class PgpDecryptVerify extends BaseOperation { this.mAllowedKeyIds = builder.mAllowedKeyIds; this.mDecryptMetadataOnly = builder.mDecryptMetadataOnly; this.mDecryptedSessionKey = builder.mDecryptedSessionKey; + this.mSignedLiteralData = builder.mSignedLiteralData; + this.mRequiredSignerFingerprint = builder.mRequiredSignerFingerprint; } public static class Builder { @@ -112,6 +117,8 @@ public class PgpDecryptVerify extends BaseOperation { private Set<Long> mAllowedKeyIds = null; private boolean mDecryptMetadataOnly = false; private byte[] mDecryptedSessionKey = null; + private String mRequiredSignerFingerprint = null; + private boolean mSignedLiteralData = false; public Builder(Context context, ProviderHelper providerHelper, Progressable progressable, @@ -123,6 +130,24 @@ public class PgpDecryptVerify extends BaseOperation { mOutStream = outStream; } + /** + * This is used when verifying signed literals to check that they are signed with + * the required key + */ + public Builder setRequiredSignerFingerprint(String fingerprint) { + mRequiredSignerFingerprint = fingerprint; + return this; + } + + /** + * This is to force a mode where the message is just the signature key id and + * then a literal data packet; used in Keybase.io proofs + */ + public Builder setSignedLiteralData(boolean signedLiteralData) { + mSignedLiteralData = signedLiteralData; + return this; + } + public Builder setAllowSymmetricDecryption(boolean allowSymmetricDecryption) { mAllowSymmetricDecryption = allowSymmetricDecryption; return this; @@ -174,7 +199,9 @@ public class PgpDecryptVerify extends BaseOperation { // it is ascii armored Log.d(Constants.TAG, "ASCII Armor Header Line: " + aIn.getArmorHeaderLine()); - if (aIn.isClearText()) { + if (mSignedLiteralData) { + return verifySignedLiteralData(aIn, 0); + } else if (aIn.isClearText()) { // a cleartext signature, verify it with the other method return verifyCleartextSignature(aIn, 0); } @@ -196,6 +223,139 @@ public class PgpDecryptVerify extends BaseOperation { } /** + * Verify Keybase.io style signed literal data + */ + private DecryptVerifyResult verifySignedLiteralData(InputStream in, int indent) throws IOException, PGPException { + OperationLog log = new OperationLog(); + log.add(LogType.MSG_VL, indent); + + // thinking that the proof-fetching operation is going to take most of the time + updateProgress(R.string.progress_reading_data, 75, 100); + + PGPObjectFactory pgpF = new PGPObjectFactory(in, new JcaKeyFingerprintCalculator()); + Object o = pgpF.nextObject(); + if (o instanceof PGPCompressedData) { + log.add(LogType.MSG_DC_CLEAR_DECOMPRESS, indent + 1); + + pgpF = new PGPObjectFactory(((PGPCompressedData) o).getDataStream(), new JcaKeyFingerprintCalculator()); + o = pgpF.nextObject(); + updateProgress(R.string.progress_decompressing_data, 80, 100); + } + + // all we want to see is a OnePassSignatureList followed by LiteralData + if (!(o instanceof PGPOnePassSignatureList)) { + log.add(LogType.MSG_VL_ERROR_MISSING_SIGLIST, indent); + return new DecryptVerifyResult(DecryptVerifyResult.RESULT_ERROR, log); + } + PGPOnePassSignatureList sigList = (PGPOnePassSignatureList) o; + + // go through all signatures (should be just one), make sure we have + // the key and it matches the one we’re looking for + CanonicalizedPublicKeyRing signingRing = null; + CanonicalizedPublicKey signingKey = null; + int signatureIndex = -1; + for (int i = 0; i < sigList.size(); ++i) { + try { + long sigKeyId = sigList.get(i).getKeyID(); + signingRing = mProviderHelper.getCanonicalizedPublicKeyRing( + KeyRings.buildUnifiedKeyRingsFindBySubkeyUri(sigKeyId) + ); + signingKey = signingRing.getPublicKey(sigKeyId); + signatureIndex = i; + } catch (ProviderHelper.NotFoundException e) { + Log.d(Constants.TAG, "key not found, trying next signature..."); + } + } + + // there has to be a key, and it has to be the right one + if (signingKey == null) { + log.add(LogType.MSG_VL_ERROR_MISSING_KEY, indent); + Log.d(Constants.TAG, "Failed to find key in signed-literal message"); + return new DecryptVerifyResult(DecryptVerifyResult.RESULT_ERROR, log); + } + + CanonicalizedPublicKey encryptKey = signingKey; + try { + encryptKey = signingRing.getEncryptionSubKey(); + } catch (PgpKeyNotFoundException e) { + } + String fingerprint = KeyFormattingUtils.convertFingerprintToHex(signingKey.getFingerprint()); + String cryptFingerprint = KeyFormattingUtils.convertFingerprintToHex(encryptKey.getFingerprint()); + if (!(mRequiredSignerFingerprint.equals(fingerprint) || mRequiredSignerFingerprint.equals(cryptFingerprint))) { + log.add(LogType.MSG_VL_ERROR_MISSING_KEY, indent); + Log.d(Constants.TAG, "Key mismatch; wanted " + mRequiredSignerFingerprint + + " got " + fingerprint + "/" + cryptFingerprint); + return new DecryptVerifyResult(DecryptVerifyResult.RESULT_ERROR, log); + } + + OpenPgpSignatureResultBuilder signatureResultBuilder = new OpenPgpSignatureResultBuilder(); + + PGPOnePassSignature signature = sigList.get(signatureIndex); + signatureResultBuilder.initValid(signingRing, signingKey); + + JcaPGPContentVerifierBuilderProvider contentVerifierBuilderProvider = + new JcaPGPContentVerifierBuilderProvider() + .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME); + signature.init(contentVerifierBuilderProvider, signingKey.getPublicKey()); + + o = pgpF.nextObject(); + + if (!(o instanceof PGPLiteralData)) { + log.add(LogType.MSG_VL_ERROR_MISSING_LITERAL, indent); + return new DecryptVerifyResult(DecryptVerifyResult.RESULT_ERROR, log); + } + + PGPLiteralData literalData = (PGPLiteralData) o; + + log.add(LogType.MSG_DC_CLEAR_DATA, indent + 1); + updateProgress(R.string.progress_decrypting, 85, 100); + + InputStream dataIn = literalData.getInputStream(); + + int length; + byte[] buffer = new byte[1 << 16]; + while ((length = dataIn.read(buffer)) > 0) { + mOutStream.write(buffer, 0, length); + signature.update(buffer, 0, length); + } + + updateProgress(R.string.progress_verifying_signature, 95, 100); + log.add(LogType.MSG_VL_CLEAR_SIGNATURE_CHECK, indent + 1); + + PGPSignatureList signatureList = (PGPSignatureList) pgpF.nextObject(); + PGPSignature messageSignature = signatureList.get(signatureIndex); + + // these are not cleartext signatures! + // TODO: what about binary signatures? + signatureResultBuilder.setSignatureOnly(false); + + // Verify signature and check binding signatures + boolean validSignature = signature.verify(messageSignature); + if (validSignature) { + log.add(LogType.MSG_DC_CLEAR_SIGNATURE_OK, indent + 1); + } else { + log.add(LogType.MSG_DC_CLEAR_SIGNATURE_BAD, indent + 1); + } + signatureResultBuilder.setValidSignature(validSignature); + + if (!signatureResultBuilder.isValidSignature()) { + log.add(LogType.MSG_VL_ERROR_INTEGRITY_CHECK, indent); + return new DecryptVerifyResult(DecryptVerifyResult.RESULT_ERROR, log); + } + + updateProgress(R.string.progress_done, 100, 100); + + log.add(LogType.MSG_VL_OK, indent); + + // Return a positive result, with metadata and verification info + DecryptVerifyResult result = + new DecryptVerifyResult(DecryptVerifyResult.RESULT_OK, log); + result.setSignatureResult(signatureResultBuilder.build()); + return result; + } + + + /** * Decrypt and/or verifies binary or ascii armored pgp */ private DecryptVerifyResult decryptVerify(InputStream in, int indent) throws IOException, PGPException { |