/* * Author: Tatu Ylonen <ylo@cs.hut.fi> * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland *                    All rights reserved * * As far as I am concerned, the code I have written for this software * can be used freely for any purpose.  Any derived versions of this * software must be clearly marked as such, and if the derived work is * incompatible with the protocol description in the RFC file, it must be * called by a name other than "ssh" or "Secure Shell". * * * Copyright (c) 1999 Niels Provos.  All rights reserved. * * 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 above 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. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. * * * Description of the RSA algorithm can be found e.g. from the following * sources: * *   Bruce Schneier: Applied Cryptography.  John Wiley & Sons, 1994. * *   Jennifer Seberry and Josed Pieprzyk: Cryptography: An Introduction to *   Computer Security.  Prentice-Hall, 1989. * *   Man Young Rhee: Cryptography and Secure Data Communications.  McGraw-Hill, *   1994. * *   R. Rivest, A. Shamir, and L. M. Adleman: Cryptographic Communications *   System and Method.  US Patent 4,405,829, 1983. * *   Hans Riesel: Prime Numbers and Computer Methods for Factorization. *   Birkhauser, 1994. * *   The RSA Frequently Asked Questions document by RSA Data Security, *   Inc., 1995. * *   RSA in 3 lines of perl by Adam Back <aba@atlax.ex.ac.uk>, 1995, as * included below: * *     [gone - had to be deleted - what a pity] */#include "includes.h"RCSID("$OpenBSD: rsa.c,v 1.24 2001/12/27 18:22:16 markus Exp $");#include "rsa.h"#include "log.h"#include "xmalloc.h"voidrsa_public_encrypt(BIGNUM *out, BIGNUM *in, RSA *key){	u_char *inbuf, *outbuf;	int len, ilen, olen;	if (BN_num_bits(key->e) < 2 || !BN_is_odd(key->e))		fatal("rsa_public_encrypt() exponent too small or not odd");	olen = BN_num_bytes(key->n);	outbuf = xmalloc(olen);	ilen = BN_num_bytes(in);	inbuf = xmalloc(ilen);	BN_bn2bin(in, inbuf);	if ((len = RSA_public_encrypt(ilen, inbuf, outbuf, key,	    RSA_PKCS1_PADDING)) <= 0)		fatal("rsa_public_encrypt() failed");	BN_bin2bn(outbuf, len, out);	memset(outbuf, 0, olen);	memset(inbuf, 0, ilen);	xfree(outbuf);	xfree(inbuf);}intrsa_private_decrypt(BIGNUM *out, BIGNUM *in, RSA *key){	u_char *inbuf, *outbuf;	int len, ilen, olen;	olen = BN_num_bytes(key->n);	outbuf = xmalloc(olen);	ilen = BN_num_bytes(in);	inbuf = xmalloc(ilen);	BN_bn2bin(in, inbuf);	if ((len = RSA_private_decrypt(ilen, inbuf, outbuf, key,	    RSA_PKCS1_PADDING)) <= 0) {		error("rsa_private_decrypt() failed");	} else {		BN_bin2bn(outbuf, len, out);	}	memset(outbuf, 0, olen);	memset(inbuf, 0, ilen);	xfree(outbuf);	xfree(inbuf);	return len;}/* calculate p-1 and q-1 */voidrsa_generate_additional_parameters(RSA *rsa){	BIGNUM *aux;	BN_CTX *ctx;	if ((aux = BN_new()) == NULL)		fatal("rsa_generate_additional_parameters: BN_new failed");	if ((ctx = BN_CTX_new()) == NULL)		fatal("rsa_generate_additional_parameters: BN_CTX_new failed");	BN_sub(aux, rsa->q, BN_value_one());	BN_mod(rsa->dmq1, rsa->d, aux, ctx);	BN_sub(aux, rsa->p, BN_value_one());	BN_mod(rsa->dmp1, rsa->d, aux, ctx);	BN_clear_free(aux);	BN_CTX_free(ctx);}