Method: OpenSSL::Cipher#final

Defined in:
ossl_cipher.c

#final ⇒ String

Returns the remaining data held in the cipher object. Further calls to Cipher#update or Cipher#final will return garbage. This call should always be made as the last call of an encryption or decryption operation, after having fed the entire plaintext or ciphertext to the Cipher instance.

If an authenticated cipher was used, a CipherError is raised if the tag could not be authenticated successfully. Only call this method after setting the authentication tag and passing the entire contents of the ciphertext into the cipher.

Returns:

  • (String) 


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# File 'ossl_cipher.c', line 439

static VALUE
ossl_cipher_final(VALUE self)
{
    EVP_CIPHER_CTX *ctx;
    int out_len;
    VALUE str;

    GetCipher(self, ctx);
    str = rb_str_new(0, EVP_CIPHER_CTX_block_size(ctx));
    if (!EVP_CipherFinal_ex(ctx, (unsigned char *)RSTRING_PTR(str), &out_len))
	ossl_raise(eCipherError, NULL);
    assert(out_len <= RSTRING_LEN(str));
    rb_str_set_len(str, out_len);

    return str;
}