/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* Copyright (c) 2005-2006 Open Source Applications Foundation. All rights reserved. */

/* We are converting between the Python arbitrarily long integer and
 * the BIGNUM arbitrarily long integer by converting to and from
 * a string representation of the number (in hexadecimal).
 * Direct manipulation would be a possibility, but would require
 * tighter integration with the Python and OpenSSL internals.
 */


%{
#include <openssl/bn.h>
%}


%inline %{
PyObject *bn_rand(int bits, int top, int bottom)
{
    BIGNUM rnd;
    PyObject *ret;
    char *randhex;
    
    BN_init(&rnd);
    if (!BN_rand(&rnd, bits, top, bottom)) {
        /*Custom errors?*/
        PyErr_SetString(PyExc_Exception, ERR_reason_error_string(ERR_get_error()));
        BN_free(&rnd);
        return NULL;
    }
    
    randhex = BN_bn2hex(&rnd);
    if (!randhex) {
        /*Custom errors?*/
        PyErr_SetString(PyExc_Exception, ERR_reason_error_string(ERR_get_error()));
        BN_free(&rnd);
        return NULL;
    }
    BN_free(&rnd);
        
    ret = PyLong_FromString(randhex, NULL, 16);
    OPENSSL_free(randhex);
    return ret;
}


PyObject *bn_rand_range(PyObject *range)
{
    BIGNUM rnd;
    BIGNUM *rng = NULL;
    PyObject *ret, *tuple;
    PyObject *format, *rangePyString;
    char *randhex, *rangehex;
    
    /* Wow, it's a lot of work to convert into a hex string in C! */
    format = PyString_FromString("%x");
    if (!format) {
        return NULL;
    }
    tuple = PyTuple_New(1);
    if (!tuple) {
        Py_DECREF(format);
        PyErr_SetString(PyExc_RuntimeError, "PyTuple_New() fails");
        return NULL;
    }
    Py_INCREF(range);
    PyTuple_SET_ITEM(tuple, 0, range);
    rangePyString = PyString_Format(format, tuple);
    if (!rangePyString) {
        PyErr_SetString(PyExc_Exception, "PyString_Format failed");    
        Py_DECREF(format);
        Py_DECREF(tuple);
        return NULL;    
    }
    Py_DECREF(format);
    Py_DECREF(tuple);
    rangehex = PyString_AsString(rangePyString);
    
    if (!BN_hex2bn(&rng, rangehex)) {
        /*Custom errors?*/
        PyErr_SetString(PyExc_Exception, ERR_reason_error_string(ERR_get_error()));
        Py_DECREF(rangePyString);
        return NULL;             
    }

    Py_DECREF(rangePyString);
                 
    BN_init(&rnd);

     if (!BN_rand_range(&rnd, rng)) {
        /*Custom errors?*/
        PyErr_SetString(PyExc_Exception, ERR_reason_error_string(ERR_get_error()));
        BN_free(&rnd);
        BN_free(rng);
        return NULL;         
     }

    BN_free(rng);

    randhex = BN_bn2hex(&rnd);
    if (!randhex) {
        /*Custom errors?*/
        PyErr_SetString(PyExc_Exception, ERR_reason_error_string(ERR_get_error()));
        BN_free(&rnd);
        return NULL;
    }
    BN_free(&rnd);
        
    ret = PyLong_FromString(randhex, NULL, 16);
    OPENSSL_free(randhex);
    return ret;
}

%}