/** * set up for use with stream mode, where the key derivation function * is used to provide a stream of bytes to xor with the message. * * @param agree the key agreement used as the basis for the encryption * @param kdf the key derivation function used for byte generation * @param mac the message authentication code generator for the message */ public IESEngine( BasicAgreement agree, DerivationFunction kdf, Mac mac) { this.agree = agree; this.kdf = kdf; this.mac = mac; this.macBuf = new byte[mac.getMacSize()]; this.cipher = null; }
/** * set up for use in conjunction with a block cipher to handle the * message. * * @param agree the key agreement used as the basis for the encryption * @param kdf the key derivation function used for byte generation * @param mac the message authentication code generator for the message * @param cipher the cipher to used for encrypting the message */ public IESEngine( BasicAgreement agree, DerivationFunction kdf, Mac mac, BufferedBlockCipher cipher) { this.agree = agree; this.kdf = kdf; this.mac = mac; this.macBuf = new byte[mac.getMacSize()]; this.cipher = cipher; }
protected KeyAgreementSpi( String kaAlgorithm, BasicAgreement agreement, DerivationFunction kdf) { this.kaAlgorithm = kaAlgorithm; this.agreement = agreement; this.kdf = kdf; }
protected KeyAgreementSpi( String kaAlgorithm, BasicAgreement agreement, DerivationFunction kdf) { super(kaAlgorithm, kdf); this.kaAlgorithm = kaAlgorithm; this.agreement = agreement; }
protected JCEECDHKeyAgreement( BasicAgreement agreement) { this.agreement = agreement; }
public ByteString eciesDecrypt(PrivateKey recipientPrivateKey, ByteString cipherText) { BCECPrivateKey bcecPrivateKey = (BCECPrivateKey) recipientPrivateKey; ECNamedCurveSpec ecNamedCurveSpec = (ECNamedCurveSpec) bcecPrivateKey.getParams(); int level = SecurityLevel.from(ecNamedCurveSpec.getName()).size(); //cipherText = ephemeralPubKeyBytes + encryptedTokBytes + macBytes //ephemeralPubKeyBytes = first ((384+7)/8)*2 + 1 bytes = first 97 bytes //hmac is sha3_384 = 48 bytes or sha3_256 = 32 bytes int ephemeralPubKeyLength = ((level + 7) / 8) * 2 + 1; int hmacLength = level >> 3; int cipherTextLength = cipherText.size(); if (cipherTextLength <= ephemeralPubKeyLength + hmacLength) throw new RuntimeException(String.format("Illegal cipherText length: %d must be > %d", cipherTextLength, ephemeralPubKeyLength + hmacLength)); ByteString ephemeralPubKey = cipherText.substring(0, ephemeralPubKeyLength); ByteString encryptedContent = cipherText.substring(ephemeralPubKeyLength, cipherTextLength - hmacLength); ByteString hmac = cipherText.substring(cipherTextLength - hmacLength); ECPrivateKeyParameters ecdhPrivateKeyParameters; try { ecdhPrivateKeyParameters = (ECPrivateKeyParameters) (PrivateKeyFactory.createKey(bcecPrivateKey.getEncoded())); } catch (IOException e) { logger.error("ECIES decrypt load private key exception", e); throw new RuntimeException(e); } ECDomainParameters ecDomainParameters = ecdhPrivateKeyParameters.getParameters(); ECCurve ecCurve = ecDomainParameters.getCurve(); ECPublicKeyParameters ecPublicKeyParameters = new ECPublicKeyParameters(ecCurve.decodePoint(ephemeralPubKey.toByteArray()), ecDomainParameters); BasicAgreement agree = new ECDHBasicAgreement(); agree.init(ecdhPrivateKeyParameters); byte[] keyAgreement = agree.calculateAgreement(ecPublicKeyParameters).toByteArray(); HKDFParameters hkdfParameters = new HKDFParameters(keyAgreement, null, null); HKDFBytesGenerator hkdfBytesGenerator = new HKDFBytesGenerator(digest); hkdfBytesGenerator.init(hkdfParameters); byte[] hkdfOutputBytes = new byte[AESKEY_LENGTH + HMACKEY_LENGTH]; hkdfBytesGenerator.generateBytes(hkdfOutputBytes, 0, AESKEY_LENGTH + HMACKEY_LENGTH); ByteString hkdfOutput = ByteString.copyFrom(hkdfOutputBytes); ByteString aesKey = hkdfOutput.substring(0, AESKEY_LENGTH); ByteString hmacKey = hkdfOutput.substring(AESKEY_LENGTH, AESKEY_LENGTH + HMACKEY_LENGTH); HMac hMac = new HMac(digest); hMac.init(new KeyParameter(hmacKey.toByteArray())); hMac.update(encryptedContent.toByteArray(), 0, encryptedContent.size()); byte[] recoveredHmac = new byte[hMac.getMacSize()]; hMac.doFinal(recoveredHmac, 0); if (!MessageDigest.isEqual(hmac.toByteArray(), recoveredHmac)) { throw new RuntimeException("HMAC verify failed"); } CFBBlockCipher aesCipher = new CFBBlockCipher( new AESEngine(), BLOCK_BIT_SIZE); ByteString iv = encryptedContent.substring(0, IV_LENGTH); CipherParameters ivAndKey = new ParametersWithIV(new KeyParameter(aesKey.toByteArray()), iv.toByteArray()); aesCipher.init(false, ivAndKey); byte[] decryptedBytes = new byte[500]; aesCipher.decryptBlock(encryptedContent.substring(IV_LENGTH).toByteArray(), 0, decryptedBytes, 0); return ByteString.copyFrom(decryptedBytes); }
/** * set up for use with stream mode, where the key derivation function * is used to provide a stream of bytes to xor with the message. * * @param agree the key agreement used as the basis for the encryption * @param kdf the key derivation function used for byte generation * @param mac the message authentication code generator for the message */ public OldIESEngine( BasicAgreement agree, DerivationFunction kdf, Mac mac) { super(agree, kdf, mac); }
/** * set up for use in conjunction with a block cipher to handle the * message. * * @param agree the key agreement used as the basis for the encryption * @param kdf the key derivation function used for byte generation * @param mac the message authentication code generator for the message * @param cipher the cipher to used for encrypting the message */ public OldIESEngine( BasicAgreement agree, DerivationFunction kdf, Mac mac, BufferedBlockCipher cipher) { super(agree, kdf, mac, cipher); }
