/*

 * Copyright 1998-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include "apps.h"

#include "progs.h"

#include <ctype.h>

#include <stdio.h>

#include <string.h>

#include <openssl/bio.h>

#include <openssl/err.h>

#include <openssl/rand.h>

typedef enum OPTION_choice {

    OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,

    OPT_OUT, OPT_ENGINE, OPT_BASE64, OPT_HEX,

    OPT_R_ENUM

} OPTION_CHOICE;

const OPTIONS rand_options[] = {

    {OPT_HELP_STR, 1, '-', "Usage: %s [flags] num\n"},

    {OPT_HELP_STR, 1, '-', "Valid options are:\n"},

    {"help", OPT_HELP, '-', "Display this summary"},

    {"out", OPT_OUT, '>', "Output file"},

    OPT_R_OPTIONS,

    {"base64", OPT_BASE64, '-', "Base64 encode output"},

    {"hex", OPT_HEX, '-', "Hex encode output"},

#ifndef OPENSSL_NO_ENGINE

    {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},

#endif

    {NULL}

};

int rand_main(int argc, char **argv)

{

    ENGINE *e = NULL;

    BIO *out = NULL;

    char *outfile = NULL, *prog;

    OPTION_CHOICE o;

    int format = FORMAT_BINARY, i, num = -1, r, ret = 1;

    prog = opt_init(argc, argv, rand_options);

    while ((o = opt_next()) != OPT_EOF) {

        switch (o) {

        case OPT_EOF:

        case OPT_ERR:

 opthelp:

            BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);

            goto end;

        case OPT_HELP:

            opt_help(rand_options);

            ret = 0;

            goto end;

        case OPT_OUT:

            outfile = opt_arg();

            break;

        case OPT_ENGINE:

            e = setup_engine(opt_arg(), 0);

            break;

        case OPT_R_CASES:

            if (!opt_rand(o))

                goto end;

            break;

        case OPT_BASE64:

            format = FORMAT_BASE64;

            break;

        case OPT_HEX:

            format = FORMAT_TEXT;

            break;

        }

    }

    argc = opt_num_rest();

    argv = opt_rest();

    if (argc == 1) {

        if (!opt_int(argv[0], &num) || num <= 0)

            goto end;

    } else if (argc > 0) {

        BIO_printf(bio_err, "Extra arguments given.\n");

        goto opthelp;

    }

    out = bio_open_default(outfile, 'w', format);

    if (out == NULL)

        goto end;

    if (format == FORMAT_BASE64) {

        BIO *b64 = BIO_new(BIO_f_base64());

        if (b64 == NULL)

            goto end;

        out = BIO_push(b64, out);

    }

    while (num > 0) {

        unsigned char buf[4096];

        int chunk;

        chunk = num;

        if (chunk > (int)sizeof(buf))

            chunk = sizeof(buf);

        r = RAND_bytes(buf, chunk);

        if (r <= 0)

            goto end;

        if (format != FORMAT_TEXT) {

            if (BIO_write(out, buf, chunk) != chunk)

                goto end;

        } else {

            for (i = 0; i < chunk; i++)

                if (BIO_printf(out, "%02x", buf[i]) != 2)

                    goto end;

        }

        num -= chunk;

    }

    if (format == FORMAT_TEXT)

        BIO_puts(out, "\n");

    if (BIO_flush(out) <= 0)

        goto end;

    ret = 0;

 end:

    if (ret != 0)

        ERR_print_errors(bio_err);

    release_engine(e);

    BIO_free_all(out);

    return ret;

}