bin/tests/entropy2_test.c

/*
 * Copyright (C) 2000, 2001, 2004, 2005, 2007, 2015, 2016  Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/* $Id: entropy2_test.c,v 1.16 2007/06/19 23:46:59 tbox Exp $ */

/*! \file */

#include <config.h>

#include <stdio.h>
#include <stdlib.h>

#include <isc/entropy.h>
#include <isc/keyboard.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/string.h>
#include <isc/time.h>
#include <isc/util.h>

static void
hex_dump(const char *msg, void *data, unsigned int length) {
    unsigned int len;
    unsigned char *base;
    isc_boolean_t first = ISC_TRUE;

    base = data;

    printf("DUMP of %d bytes:  %s\n\t", length, msg);
    for (len = 0; len < length; len++) {
        if (len % 16 == 0 && !first)
            printf("\n\t");
        printf("%02x ", base[len]);
        first = ISC_FALSE;
    }
    printf("\n");
}

static void
CHECK(const char *msg, isc_result_t result) {
    if (result != ISC_R_SUCCESS) {
        printf("FAILURE:  %s:  %s\n", msg, isc_result_totext(result));
        exit(1);
    }
}

static isc_result_t
start(isc_entropysource_t *source, void *arg, isc_boolean_t blocking) {
    isc_keyboard_t *kbd = (isc_keyboard_t *)arg;

    UNUSED(source);

    if (blocking)
        printf("start called, blocking mode.\n");
    else
        printf("start called, non-blocking mode.\n");

    return (isc_keyboard_open(kbd));
}

static void
stop(isc_entropysource_t *source, void *arg) {
    isc_keyboard_t *kbd = (isc_keyboard_t *)arg;

    UNUSED(source);

    printf("ENOUGH!  Stop typing, please.\r\n");

    (void)isc_keyboard_close(kbd, 3);
    printf("stop called\n");
}

static isc_result_t
get(isc_entropysource_t *source, void *arg, isc_boolean_t blocking) {
    isc_keyboard_t *kbd = (isc_keyboard_t *)arg;
    isc_result_t result;
    isc_time_t t;
    isc_uint32_t sample;
    isc_uint32_t extra;
    unsigned char c;

    if (!blocking)
        return (ISC_R_NOENTROPY);

    result = isc_keyboard_getchar(kbd, &c);
    if (result != ISC_R_SUCCESS)
        return (result);

    TIME_NOW(&t);

    sample = isc_time_nanoseconds(&t);
    extra = c;

    result = isc_entropy_addcallbacksample(source, sample, extra);
    if (result != ISC_R_SUCCESS) {
        printf("\r\n");
        return (result);
    }

    printf(".");
    fflush(stdout);

    return (result);
}

int
main(int argc, char **argv) {
    isc_mem_t *mctx;
    unsigned char buffer[512];
    isc_entropy_t *ent;
    isc_entropysource_t *source;
    unsigned int returned;
    unsigned int flags;
    isc_result_t result;
    isc_keyboard_t kbd;

    UNUSED(argc);
    UNUSED(argv);

    mctx = NULL;
    CHECK("isc_mem_create()",
          isc_mem_create(0, 0, &mctx));

    ent = NULL;
    CHECK("isc_entropy_create()",
          isc_entropy_create(mctx, &ent));

    isc_entropy_stats(ent, stderr);

    source = NULL;
    result = isc_entropy_createcallbacksource(ent, start, get, stop, &kbd,
                          &source);
    CHECK("isc_entropy_createcallbacksource()", result);

    fprintf(stderr,
        "Reading 32 bytes of GOOD random data only, partial OK\n");

    flags = 0;
    flags |= ISC_ENTROPY_GOODONLY;
    flags |= ISC_ENTROPY_PARTIAL;
    flags |= ISC_ENTROPY_BLOCKING;
    returned = 0;
    result = isc_entropy_getdata(ent, buffer, 32, &returned, flags);
    if (result == ISC_R_NOENTROPY) {
        fprintf(stderr, "No entropy.\r\n");
    }

    isc_entropy_stopcallbacksources(ent);

    hex_dump("good data only:", buffer, returned);

    isc_entropy_stats(ent, stderr);

    isc_entropy_destroysource(&source);
    isc_entropy_detach(&ent);

    isc_mem_stats(mctx, stderr);
    isc_mem_destroy(&mctx);

    return (0);
}