Question

I have this following snippet from c++ code that is used for encryption:

EVP_CIPHER_CTX ctx;
const EVP_CIPHER * cipher = EVP_des_ede3_cbc();
unsigned char iv[EVP_MAX_IV_LENGTH];
unsigned char key[EVP_MAX_KEY_LENGTH];
String seed;

_config->get_value("crypto_seed", &seed); // uses the seed value from pimp config.

if (seed.is_empty())
{
    return false;
}

EVP_BytesToKey(cipher, EVP_sha1(),
        (unsigned char *) 0, // no salt
        reinterpret_cast<unsigned char *>(const_cast<char *>(seed.chars())), seed.length(),
        1, // hash passphrase just once.
        key, iv);

EVP_CIPHER_CTX_init(&ctx);
EVP_CipherInit_ex(&ctx, cipher, (ENGINE *) 0, key,
        iv,
        1); // encrypt

what s the equivalent of the c++ encryption in java?

I see there is des algorithm, then i see sha1.

This is related to openssl encryption. But not sure what is the equivalent. essentially i would like the same output as c++ code generates.

i m asking the what s the equivalent of EVP_CIPHER_CTX or what s the name of the encrytion being used here so i can take it from there.

EDIT: not asking anyone to convert the code to java, just asking the corresponding package or class that would do the same.

Answer 1

The code you are converting from uses the openssl library. It carries out a triple-DES encryption using an Initial Vector. The first thing you need to understand is exactly what it’s doing (and preferably why).

Unfortunately the openssl documentation isn’t terribly thorough (see here) … though the O’Reilley book Network Security with OpenSSL is quite a bit better (it’s a bit out of date, though).

Once you know what needs to be done, you shouldn’t have much difficulty coding it in Java using the standard javax.crypto package.