root/third_party/tlslite/tlslite/utils/win32prng.c

DEFINITIONS

1. getRandomBytes
2. DL_EXPORT

#include "Python.h"
#define _WIN32_WINNT 0x0400       /* Needed for CryptoAPI on some systems */
#include <windows.h>


static PyObject* getRandomBytes(PyObject *self, PyObject *args)
{
        int howMany;
        HCRYPTPROV hCryptProv;
        unsigned char* bytes = NULL;
        PyObject* returnVal = NULL;


        /* Read Arguments */
    if (!PyArg_ParseTuple(args, "i", &howMany))
        return(NULL);

        /* Get Context */
        if(CryptAcquireContext(
           &hCryptProv,
           NULL,
           NULL,
           PROV_RSA_FULL,
           CRYPT_VERIFYCONTEXT) == 0)
                return Py_BuildValue("s#", NULL, 0);


        /* Allocate bytes */
        bytes = malloc(howMany);


        /* Get random data */
        if(CryptGenRandom(
           hCryptProv,
           howMany,
           bytes) == 0)
                returnVal = Py_BuildValue("s#", NULL, 0);
        else
                returnVal = Py_BuildValue("s#", bytes, howMany);

        free(bytes);
        CryptReleaseContext(hCryptProv, 0);

        return returnVal;
}



/* List of functions exported by this module */

static struct PyMethodDef win32prng_functions[] = {
    {"getRandomBytes", (PyCFunction)getRandomBytes, METH_VARARGS},
    {NULL,  NULL}        /* Sentinel */
};


/* Initialize this module. */

DL_EXPORT(void) initwin32prng(void)
{
    Py_InitModule("win32prng", win32prng_functions);
}