private static byte[] decrypt(byte[] decoded, String dekInfo, char[] passwd)
throws IOException, GeneralSecurityException {
if (passwd == null) {
throw new IOException("Password is null, but a password is required");
}
StringTokenizer tknz = new StringTokenizer(dekInfo, ",");
String algorithm = tknz.nextToken();
byte[] iv = Hex.decode(tknz.nextToken());
if (!CipherModule.isSupportedCipher(algorithm)) {
throw new IOException("Unknown algorithm: " + algorithm);
}
String[] cipher = org.jruby.ext.openssl.Cipher.Algorithm.osslToJsse(algorithm);
String realName = cipher[3];
int[] lengths = org.jruby.ext.openssl.Cipher.Algorithm.osslKeyIvLength(algorithm);
int keyLen = lengths[0];
int ivLen = lengths[1];
if (iv.length != ivLen) {
throw new IOException("Illegal IV length");
}
byte[] salt = new byte[8];
System.arraycopy(iv, 0, salt, 0, 8);
OpenSSLPBEParametersGenerator pGen = new OpenSSLPBEParametersGenerator();
pGen.init(PBEParametersGenerator.PKCS5PasswordToBytes(passwd), salt);
KeyParameter param = (KeyParameter) pGen.generateDerivedParameters(keyLen * 8);
SecretKey secretKey = new javax.crypto.spec.SecretKeySpec(param.getKey(), realName);
Cipher c = Cipher.getInstance(realName);
c.init(Cipher.DECRYPT_MODE, secretKey, new IvParameterSpec(iv));
return c.doFinal(decoded);
}
private static void writePemEncrypted(
BufferedWriter out, String pemHeader, byte[] encoding, CipherSpec cipher, char[] passwd)
throws IOException {
Cipher c = cipher.getCipher();
byte[] iv = new byte[c.getBlockSize()];
random.nextBytes(iv);
byte[] salt = new byte[8];
System.arraycopy(iv, 0, salt, 0, 8);
OpenSSLPBEParametersGenerator pGen = new OpenSSLPBEParametersGenerator();
pGen.init(PBEParametersGenerator.PKCS5PasswordToBytes(passwd), salt);
KeyParameter param = (KeyParameter) pGen.generateDerivedParameters(cipher.getKeyLenInBits());
SecretKey secretKey =
new SecretKeySpec(
param.getKey(), org.jruby.ext.openssl.Cipher.Algorithm.getAlgorithmBase(c));
byte[] encData = null;
try {
c.init(Cipher.ENCRYPT_MODE, secretKey, new IvParameterSpec(iv));
encData = c.doFinal(encoding);
} catch (GeneralSecurityException gse) {
throw new IOException("exception using cipher: " + gse.toString());
}
out.write(BEF_G + pemHeader + AFT);
out.newLine();
out.write("Proc-Type: 4,ENCRYPTED");
out.newLine();
out.write("DEK-Info: " + cipher.getOsslName() + ",");
writeHexEncoded(out, iv);
out.newLine();
out.newLine();
writeEncoded(out, encData);
out.write(BEF_E + pemHeader + AFT);
out.flush();
}