BouncyCastle PGP を使用してシングルパスで署名および暗号化されたメッセージを銀行が復号化できない理由を突き止めようと、2 週間ほど頭を悩ませてきました。この銀行は、復号化に McAfee E-Business Server 8.6 を使用しています。
データは銀行の公開鍵で暗号化され、当社の秘密鍵で署名されています。
暗号化に独自の公開鍵を使用することで、以下のコードで生成されたファイルの署名を復号化して検証することができました。Gnupg は、ファイルを問題なく復号化および検証できます。
ただし、銀行はファイルを復号化できません。最初に圧縮をオフにしてから、ASCII アーマーをオフにしようとしました。どちらのオプションも機能していないようで、どのオプションを試しても常に同じエラー メッセージが表示されます。
event 1: initial
event 13: BeginLex
event 8: Analyze
File is encrypted. event 9: Recipients
Secret key is required to read it.
Key for user ID "XXXXXXXXX <XXXXXX@XXXX>"
event 6: Passphrase
event 23: Decryption
symmetric cipher used: CAST5
event 3: error -11391
event 2: final
Error decrypting file '/somepath/FILENAME'.
Corrupt data.
Bad packet
exitcode = 32
シングルパス署名と暗号化を行うために使用しているコードは次のとおりです。
public class PGPService {
private static final Logger log = Logger.getLogger(PGPService.class);
static {
Security.addProvider(new BouncyCastleProvider());
}
/**
* A simple routine that opens a key ring file and loads the first available key
* suitable for signature generation.
*
* @param input stream to read the secret key ring collection from.
* @return a secret key.
* @throws IOException on a problem with using the input stream.
* @throws PGPException if there is an issue parsing the input stream.
*/
@SuppressWarnings("rawtypes")
private static PGPSecretKey readSecretKey(InputStream input) throws IOException, PGPException {
PGPSecretKeyRingCollection pgpSec = new PGPSecretKeyRingCollection(
PGPUtil.getDecoderStream(input));
// We just loop through the collection till we find a key suitable for encryption, in the real
// world you would probably want to be a bit smarter about this.
Iterator keyRingIter = pgpSec.getKeyRings();
while (keyRingIter.hasNext()) {
PGPSecretKeyRing keyRing = (PGPSecretKeyRing)keyRingIter.next();
Iterator keyIter = keyRing.getSecretKeys();
while (keyIter.hasNext()) {
PGPSecretKey key = (PGPSecretKey)keyIter.next();
if (key.isSigningKey()) {
return key;
}
}
}
throw new IllegalArgumentException("Can't find signing key in key ring.");
}
/**
* Single pass signs and encrypts the given file to the given output file using the provided keys.
*
* @param fileNameIn - The name and location of the source input file.
* @param fileNameOut - The name and location of the destination output file.
* @param privateKeyIn - The input stream for the private key file.
* @param privateKeyPassword - The password for the private key file.
* @param publicEncryptionKey - The public encryption key.
* @param armoredOutput - Whether or not to ASCII armor the output.
*/
@SuppressWarnings("rawtypes")
public static void signAndEncrypt(String fileNameIn, String fileNameOut, InputStream privateKeyIn, String privateKeyPassword, PGPPublicKey publicEncryptionKey, boolean armoredOutput, boolean compress) {
int bufferSize = 1<<16;
InputStream input = null;
OutputStream finalOut = null;
OutputStream encOut = null;
OutputStream compressedOut = null;
OutputStream literalOut = null;
PGPEncryptedDataGenerator encryptedDataGenerator = null;
PGPCompressedDataGenerator compressedDataGenerator = null;
PGPSignatureGenerator signatureGenerator = null;
PGPLiteralDataGenerator literalDataGenerator = null;
try {
File output = new File(fileNameOut);
OutputStream out = new FileOutputStream(output);
if (armoredOutput) out = new ArmoredOutputStream(out);
// ? Use BCPGOutputStreams ?
// Init encrypted data generator
encryptedDataGenerator = new PGPEncryptedDataGenerator(PGPEncryptedDataGenerator.CAST5, true, new SecureRandom(), "BC");
encryptedDataGenerator.addMethod(publicEncryptionKey);
finalOut = new BufferedOutputStream(out, bufferSize);
encOut = encryptedDataGenerator.open(finalOut, new byte[bufferSize]);
// Init compression
if (compress) {
compressedDataGenerator = new PGPCompressedDataGenerator(PGPCompressedData.ZLIB);
compressedOut = new BufferedOutputStream(compressedDataGenerator.open(encOut));
}
// Init signature
PGPSecretKey pgpSec = readSecretKey(privateKeyIn);
PGPPrivateKey pgpPrivKey = pgpSec.extractPrivateKey(privateKeyPassword.toCharArray(), "BC");
signatureGenerator = new PGPSignatureGenerator(pgpSec.getPublicKey().getAlgorithm(), PGPUtil.SHA1, "BC");
signatureGenerator.initSign(PGPSignature.CANONICAL_TEXT_DOCUMENT, pgpPrivKey);
Iterator it = pgpSec.getPublicKey().getUserIDs();
if (it.hasNext()) {
PGPSignatureSubpacketGenerator spGen = new PGPSignatureSubpacketGenerator();
spGen.setSignerUserID(false, (String)it.next());
signatureGenerator.setHashedSubpackets(spGen.generate());
}
PGPOnePassSignature onePassSignature = signatureGenerator.generateOnePassVersion(false);
if (compress) onePassSignature.encode(compressedOut);
else onePassSignature.encode(encOut);
// Create the Literal Data generator Output stream which writes to the compression stream
literalDataGenerator = new PGPLiteralDataGenerator(true);
if (compress) literalOut = literalDataGenerator.open(compressedOut, PGPLiteralData.BINARY, output.getName(), new Date(), new byte[bufferSize]);
else literalOut = literalDataGenerator.open(encOut, PGPLiteralData.TEXT, fileNameIn, new Date(), new byte[bufferSize]);
// Update sign and encrypt
byte[] buffer = new byte[bufferSize];
int bytesRead = 0;
input = new FileInputStream(fileNameIn);
while((bytesRead = input.read(buffer)) != -1) {
literalOut.write(buffer,0,bytesRead);
signatureGenerator.update(buffer,0,bytesRead);
literalOut.flush();
}
// Close Literal data stream and add signature
literalOut.close();
literalDataGenerator.close();
if (compress) signatureGenerator.generate().encode(compressedOut);
else signatureGenerator.generate().encode(encOut);
} catch (Exception e) {
log.error(e);
throw new RuntimeException(e);
} finally {
// Close all streams
if (literalOut != null) try { literalOut.close(); } catch (IOException e) {}
if (literalDataGenerator != null) try { literalDataGenerator.close(); } catch (IOException e) {}
if (compressedOut != null) try { compressedOut.close(); } catch (IOException e) {}
if (compressedDataGenerator != null) try { compressedDataGenerator.close(); } catch (IOException e) {}
if (encOut != null) try { encOut.close(); } catch (IOException e) {}
if (encryptedDataGenerator != null) try { encryptedDataGenerator.close(); } catch (IOException e) {}
if (finalOut != null) try { finalOut.close(); } catch (IOException e) {}
if (input != null) try { input.close(); } catch (IOException e) {}
}
}
@SuppressWarnings("rawtypes")
private static PGPPublicKey readPublicKeyFromCol(InputStream in) throws Exception {
PGPPublicKeyRing pkRing = null;
PGPPublicKeyRingCollection pkCol = new PGPPublicKeyRingCollection(in);
log.info("Key ring size = " + pkCol.size());
Iterator it = pkCol.getKeyRings();
while (it.hasNext()) {
pkRing = (PGPPublicKeyRing) it.next();
Iterator pkIt = pkRing.getPublicKeys();
while (pkIt.hasNext()) {
PGPPublicKey key = (PGPPublicKey) pkIt.next();
log.info("Encryption key = " + key.isEncryptionKey() + ", Master key = " +
key.isMasterKey());
if (key.isEncryptionKey()) {
// Find out a little about the keys in the public key ring.
log.info("Key Strength = " + key.getBitStrength());
log.info("Algorithm = " + key.getAlgorithm());
log.info("Bit strength = " + key.getBitStrength());
log.info("Version = " + key.getVersion());
return key;
}
}
}
return null;
}
private static PGPPrivateKey findSecretKey(InputStream keyIn, long keyID, char[] pass)
throws IOException, PGPException, NoSuchProviderException {
PGPSecretKeyRingCollection pgpSec = new PGPSecretKeyRingCollection(PGPUtil.getDecoderStream(keyIn));
PGPSecretKey pgpSecKey = pgpSec.getSecretKey(keyID);
if (pgpSecKey == null) {
return null;
}
return pgpSecKey.extractPrivateKey(pass, "BC");
}
}
何がこれを引き起こしているのでしょうか？Google を使用して多数のレポートを見つけましたが、解決策やフォローアップはありません。