/* $OpenBSD: genrsa.c,v 1.9 2017/01/20 08:57:12 deraadt Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <openssl/opensslconf.h>

/* Until the key-gen callbacks are modified to use newer prototypes, we allow
 * deprecated functions for openssl-internal code */
#ifdef OPENSSL_NO_DEPRECATED
#undef OPENSSL_NO_DEPRECATED
#endif


#include <sys/types.h>
#include <sys/stat.h>

#include <stdio.h>
#include <string.h>

#include "apps.h"

#include <openssl/bio.h>
#include <openssl/bn.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/pem.h>
#include <openssl/rsa.h>
#include <openssl/x509.h>

#define DEFBITS	2048

static int genrsa_cb(int p, int n, BN_GENCB * cb);

int
genrsa_main(int argc, char **argv)
{
	BN_GENCB cb;
	int ret = 1;
	int i, num = DEFBITS;
	long l;
	const EVP_CIPHER *enc = NULL;
	unsigned long f4 = RSA_F4;
	char *outfile = NULL;
	char *passargout = NULL, *passout = NULL;
	BIO *out = NULL;
	BIGNUM *bn = BN_new();
	RSA *rsa = NULL;

	if (single_execution) {
		if (pledge("stdio cpath wpath rpath tty", NULL) == -1) {
			perror("pledge");
			exit(1);
		}
	}

	if (!bn)
		goto err;

	BN_GENCB_set(&cb, genrsa_cb, bio_err);

	if ((out = BIO_new(BIO_s_file())) == NULL) {
		BIO_printf(bio_err, "unable to create BIO for output\n");
		goto err;
	}
	argv++;
	argc--;
	for (;;) {
		if (argc <= 0)
			break;
		if (strcmp(*argv, "-out") == 0) {
			if (--argc < 1)
				goto bad;
			outfile = *(++argv);
		} else if (strcmp(*argv, "-3") == 0)
			f4 = 3;
		else if (strcmp(*argv, "-F4") == 0 || strcmp(*argv, "-f4") == 0)
			f4 = RSA_F4;
#ifndef OPENSSL_NO_DES
		else if (strcmp(*argv, "-des") == 0)
			enc = EVP_des_cbc();
		else if (strcmp(*argv, "-des3") == 0)
			enc = EVP_des_ede3_cbc();
#endif
#ifndef OPENSSL_NO_IDEA
		else if (strcmp(*argv, "-idea") == 0)
			enc = EVP_idea_cbc();
#endif
#ifndef OPENSSL_NO_AES
		else if (strcmp(*argv, "-aes128") == 0)
			enc = EVP_aes_128_cbc();
		else if (strcmp(*argv, "-aes192") == 0)
			enc = EVP_aes_192_cbc();
		else if (strcmp(*argv, "-aes256") == 0)
			enc = EVP_aes_256_cbc();
#endif
#ifndef OPENSSL_NO_CAMELLIA
		else if (strcmp(*argv, "-camellia128") == 0)
			enc = EVP_camellia_128_cbc();
		else if (strcmp(*argv, "-camellia192") == 0)
			enc = EVP_camellia_192_cbc();
		else if (strcmp(*argv, "-camellia256") == 0)
			enc = EVP_camellia_256_cbc();
#endif
		else if (strcmp(*argv, "-passout") == 0) {
			if (--argc < 1)
				goto bad;
			passargout = *(++argv);
		} else
			break;
		argv++;
		argc--;
	}
	if ((argc >= 1) && ((sscanf(*argv, "%d", &num) == 0) || (num < 0))) {
bad:
		BIO_printf(bio_err, "usage: genrsa [args] [numbits]\n");
		BIO_printf(bio_err, " -des            encrypt the generated key with DES in cbc mode\n");
		BIO_printf(bio_err, " -des3           encrypt the generated key with DES in ede cbc mode (168 bit key)\n");
#ifndef OPENSSL_NO_IDEA
		BIO_printf(bio_err, " -idea           encrypt the generated key with IDEA in cbc mode\n");
#endif
#ifndef OPENSSL_NO_AES
		BIO_printf(bio_err, " -aes128, -aes192, -aes256\n");
		BIO_printf(bio_err, "                 encrypt PEM output with cbc aes\n");
#endif
#ifndef OPENSSL_NO_CAMELLIA
		BIO_printf(bio_err, " -camellia128, -camellia192, -camellia256\n");
		BIO_printf(bio_err, "                 encrypt PEM output with cbc camellia\n");
#endif
		BIO_printf(bio_err, " -out file       output the key to 'file\n");
		BIO_printf(bio_err, " -passout arg    output file pass phrase source\n");
		BIO_printf(bio_err, " -f4             use F4 (0x10001) for the E value\n");
		BIO_printf(bio_err, " -3              use 3 for the E value\n");
		goto err;
	}

	if (!app_passwd(bio_err, NULL, passargout, NULL, &passout)) {
		BIO_printf(bio_err, "Error getting password\n");
		goto err;
	}

	if (outfile == NULL) {
		BIO_set_fp(out, stdout, BIO_NOCLOSE);
	} else {
		if (BIO_write_filename(out, outfile) <= 0) {
			perror(outfile);
			goto err;
		}
	}

	BIO_printf(bio_err, "Generating RSA private key, %d bit long modulus\n",
	    num);
	rsa = RSA_new();
	if (!rsa)
		goto err;

	if (!BN_set_word(bn, f4) || !RSA_generate_key_ex(rsa, num, bn, &cb))
		goto err;

	/*
	 * We need to do the following for when the base number size is <
	 * long, esp windows 3.1 :-(.
	 */
	l = 0L;
	for (i = 0; i < rsa->e->top; i++) {
#ifndef _LP64
		l <<= BN_BITS4;
		l <<= BN_BITS4;
#endif
		l += rsa->e->d[i];
	}
	BIO_printf(bio_err, "e is %ld (0x%lX)\n", l, l);
	{
		PW_CB_DATA cb_data;
		cb_data.password = passout;
		cb_data.prompt_info = outfile;
		if (!PEM_write_bio_RSAPrivateKey(out, rsa, enc, NULL, 0,
			password_callback, &cb_data))
			goto err;
	}

	ret = 0;
err:
	if (bn)
		BN_free(bn);
	if (rsa)
		RSA_free(rsa);
	if (out)
		BIO_free_all(out);
	free(passout);
	if (ret != 0)
		ERR_print_errors(bio_err);

	return (ret);
}

static int
genrsa_cb(int p, int n, BN_GENCB * cb)
{
	char c = '*';

	if (p == 0)
		c = '.';
	if (p == 1)
		c = '+';
	if (p == 2)
		c = '*';
	if (p == 3)
		c = '\n';
	BIO_write(cb->arg, &c, 1);
	(void) BIO_flush(cb->arg);
	return 1;
}
