Enable setting RSA OAEP label in Decrypter

        }

    }

    /// Sets the RSA OAEP label.

    ///

    /// This is only useful for RSA keys.

    ///

    /// This corresponds to [`EVP_PKEY_CTX_set0_rsa_oaep_label`].

    ///

    /// [`EVP_PKEY_CTX_set0_rsa_oaep_label`]: https://www.openssl.org/docs/manmaster/man3/EVP_PKEY_CTX_set0_rsa_oaep_label.html

    #[cfg(any(ossl102, libressl310))]

    pub fn set_rsa_oaep_label(&mut self, label: &[u8]) -> Result<(), ErrorStack> {

        unsafe {

            let p = cvt_p(ffi::OPENSSL_malloc(label.len() as _))?;

            ptr::copy_nonoverlapping(label.as_ptr(), p as *mut u8, label.len());

            cvt(ffi::EVP_PKEY_CTX_set0_rsa_oaep_label(

                self.pctx,

                p as *mut c_void,

                label.len() as c_int,

            ))

            .map(|_| ())

            .map_err(|e| {

                ffi::OPENSSL_free(p);

                e

            })

        }

    }

    /// Performs public key decryption.

    ///

    /// In order to know the size needed for the output buffer, use [`decrypt_len`](Decrypter::decrypt_len).

        assert_eq!(decoded, &*input);

    }

    #[test]

    #[cfg(any(ossl102, libressl310))]

    fn rsa_encrypt_decrypt_oaep_label() {

        let key = include_bytes!("../test/rsa.pem");

        let private_key = Rsa::private_key_from_pem(key).unwrap();

        let pkey = PKey::from_rsa(private_key).unwrap();

        let mut encrypter = Encrypter::new(&pkey).unwrap();

        encrypter.set_rsa_padding(Padding::PKCS1_OAEP).unwrap();

        encrypter.set_rsa_oaep_label(b"test_oaep_label").unwrap();

        let input = Vec::from_hex(INPUT).unwrap();

        let buffer_len = encrypter.encrypt_len(&input).unwrap();

        let mut encoded = vec![0u8; buffer_len];

        let encoded_len = encrypter.encrypt(&input, &mut encoded).unwrap();

        let encoded = &encoded[..encoded_len];

        let mut decrypter = Decrypter::new(&pkey).unwrap();

        decrypter.set_rsa_padding(Padding::PKCS1_OAEP).unwrap();

        decrypter.set_rsa_oaep_label(b"test_oaep_label").unwrap();

        let buffer_len = decrypter.decrypt_len(encoded).unwrap();

        let mut decoded = vec![0u8; buffer_len];

        let decoded_len = decrypter.decrypt(encoded, &mut decoded).unwrap();

        let decoded = &decoded[..decoded_len];

        assert_eq!(decoded, &*input);

        decrypter.set_rsa_oaep_label(b"wrong_oaep_label").unwrap();

        let buffer_len = decrypter.decrypt_len(encoded).unwrap();

        let mut decoded = vec![0u8; buffer_len];

        assert!(decrypter.decrypt(encoded, &mut decoded).is_err());

    }

}