[openssh.git] / rsa.c

/*
 * 
 * rsa.c
 * 
 * Author: Tatu Ylonen <ylo@cs.hut.fi>
 * 
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 * 
 * Created: Fri Mar  3 22:07:06 1995 ylo
 * 
 * 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("$Id$");

#include "rsa.h"
#include "ssh.h"
#include "xmalloc.h"

int rsa_verbose = 1;

int
rsa_alive()
{
	RSA *key;

	key = RSA_generate_key(32, 3, NULL, NULL);
	if (key == NULL)
		return (0);
	RSA_free(key);
	return (1);
}

/*
 * Generates RSA public and private keys.  This initializes the data
 * structures; they should be freed with rsa_clear_private_key and
 * rsa_clear_public_key.
 */

void
rsa_generate_key(RSA *prv, RSA *pub, unsigned int bits)
{
	RSA *key;

	if (rsa_verbose) {
		printf("Generating RSA keys:  ");
		fflush(stdout);
	}
	key = RSA_generate_key(bits, 35, NULL, NULL);
	if (key == NULL)
		fatal("rsa_generate_key: key generation failed.");

	/* Copy public key parameters */
	pub->n = BN_new();
	BN_copy(pub->n, key->n);
	pub->e = BN_new();
	BN_copy(pub->e, key->e);

	/* Copy private key parameters */
	prv->n = BN_new();
	BN_copy(prv->n, key->n);
	prv->e = BN_new();
	BN_copy(prv->e, key->e);
	prv->d = BN_new();
	BN_copy(prv->d, key->d);
	prv->p = BN_new();
	BN_copy(prv->p, key->p);
	prv->q = BN_new();
	BN_copy(prv->q, key->q);

	prv->dmp1 = BN_new();
	BN_copy(prv->dmp1, key->dmp1);

	prv->dmq1 = BN_new();
	BN_copy(prv->dmq1, key->dmq1);

	prv->iqmp = BN_new();
	BN_copy(prv->iqmp, key->iqmp);

	RSA_free(key);

	if (rsa_verbose)
		printf("Key generation complete.\n");
}

void
rsa_public_encrypt(BIGNUM *out, BIGNUM *in, RSA *key)
{
	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);
}

void
rsa_private_decrypt(BIGNUM *out, BIGNUM *in, RSA *key)
{
	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_SSLV23_PADDING)) <= 0)
		fatal("rsa_private_decrypt() failed");

	BN_bin2bn(outbuf, len, out);

	memset(outbuf, 0, olen);
	memset(inbuf, 0, ilen);
	xfree(outbuf);
	xfree(inbuf);
}

/* Set whether to output verbose messages during key generation. */

void
rsa_set_verbose(int verbose)
{
	rsa_verbose = verbose;
}
Commit	Line	Data
8efc0c15	1	/*
5260325f	2	*
	3	* rsa.c
	4	*
	5	* Author: Tatu Ylonen <ylo@cs.hut.fi>
	6	*
	7	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
	8	* All rights reserved
	9	*
	10	* Created: Fri Mar 3 22:07:06 1995 ylo
	11	*
	12	* Description of the RSA algorithm can be found e.g. from the following sources:
	13	*
	14	* Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1994.
	15	*
	16	* Jennifer Seberry and Josed Pieprzyk: Cryptography: An Introduction to
	17	* Computer Security. Prentice-Hall, 1989.
	18	*
	19	* Man Young Rhee: Cryptography and Secure Data Communications. McGraw-Hill,
	20	* 1994.
	21	*
	22	* R. Rivest, A. Shamir, and L. M. Adleman: Cryptographic Communications
	23	* System and Method. US Patent 4,405,829, 1983.
	24	*
	25	* Hans Riesel: Prime Numbers and Computer Methods for Factorization.
	26	* Birkhauser, 1994.
	27	*
	28	* The RSA Frequently Asked Questions document by RSA Data Security, Inc., 1995.
	29	*
	30	* RSA in 3 lines of perl by Adam Back <aba@atlax.ex.ac.uk>, 1995, as included
	31	* below:
	32	*
	33	* [gone - had to be deleted - what a pity]
	34	*
8efc0c15	35	*/
	36
	37	#include "includes.h"
	38	RCSID("$Id$");
	39
	40	#include "rsa.h"
	41	#include "ssh.h"
	42	#include "xmalloc.h"
	43
	44	int rsa_verbose = 1;
	45
	46	int
	47	rsa_alive()
	48	{
5260325f	49	RSA *key;
8efc0c15	50
5260325f	51	key = RSA_generate_key(32, 3, NULL, NULL);
	52	if (key == NULL)
	53	return (0);
	54	RSA_free(key);
	55	return (1);
8efc0c15	56	}
8efc0c15	57
aa3378df	58	/*
	59	* Generates RSA public and private keys. This initializes the data
	60	* structures; they should be freed with rsa_clear_private_key and
	61	* rsa_clear_public_key.
	62	*/
8efc0c15	63
	64	void
	65	rsa_generate_key(RSA prv, RSA pub, unsigned int bits)
	66	{
5260325f	67	RSA *key;
	68
	69	if (rsa_verbose) {
	70	printf("Generating RSA keys: ");
	71	fflush(stdout);
	72	}
	73	key = RSA_generate_key(bits, 35, NULL, NULL);
	74	if (key == NULL)
	75	fatal("rsa_generate_key: key generation failed.");
	76
	77	/* Copy public key parameters */
	78	pub->n = BN_new();
	79	BN_copy(pub->n, key->n);
	80	pub->e = BN_new();
	81	BN_copy(pub->e, key->e);
	82
	83	/* Copy private key parameters */
	84	prv->n = BN_new();
	85	BN_copy(prv->n, key->n);
	86	prv->e = BN_new();
	87	BN_copy(prv->e, key->e);
	88	prv->d = BN_new();
	89	BN_copy(prv->d, key->d);
	90	prv->p = BN_new();
	91	BN_copy(prv->p, key->p);
	92	prv->q = BN_new();
	93	BN_copy(prv->q, key->q);
	94
	95	prv->dmp1 = BN_new();
	96	BN_copy(prv->dmp1, key->dmp1);
	97
	98	prv->dmq1 = BN_new();
	99	BN_copy(prv->dmq1, key->dmq1);
	100
	101	prv->iqmp = BN_new();
	102	BN_copy(prv->iqmp, key->iqmp);
	103
	104	RSA_free(key);
	105
	106	if (rsa_verbose)
	107	printf("Key generation complete.\n");
8efc0c15	108	}
	109
	110	void
5260325f	111	rsa_public_encrypt(BIGNUM out, BIGNUM in, RSA *key)
8efc0c15	112	{
5260325f	113	char inbuf, outbuf;
5260325f	114	int len, ilen, olen;
8efc0c15	115
5260325f	116	if (BN_num_bits(key->e) < 2 \|\| !BN_is_odd(key->e))
5260325f	117	fatal("rsa_public_encrypt() exponent too small or not odd");
8efc0c15	118
5260325f	119	olen = BN_num_bytes(key->n);
5260325f	120	outbuf = xmalloc(olen);
8efc0c15	121
5260325f	122	ilen = BN_num_bytes(in);
	123	inbuf = xmalloc(ilen);
	124	BN_bn2bin(in, inbuf);
8efc0c15	125
5260325f	126	if ((len = RSA_public_encrypt(ilen, inbuf, outbuf, key,
	127	RSA_PKCS1_PADDING)) <= 0)
	128	fatal("rsa_public_encrypt() failed");
8efc0c15	129
5260325f	130	BN_bin2bn(outbuf, len, out);
8efc0c15	131
5260325f	132	memset(outbuf, 0, olen);
	133	memset(inbuf, 0, ilen);
	134	xfree(outbuf);
	135	xfree(inbuf);
8efc0c15	136	}
	137
	138	void
	139	rsa_private_decrypt(BIGNUM out, BIGNUM in, RSA *key)
	140	{
5260325f	141	char inbuf, outbuf;
5260325f	142	int len, ilen, olen;
8efc0c15	143
5260325f	144	olen = BN_num_bytes(key->n);
5260325f	145	outbuf = xmalloc(olen);
8efc0c15	146
5260325f	147	ilen = BN_num_bytes(in);
	148	inbuf = xmalloc(ilen);
	149	BN_bn2bin(in, inbuf);
8efc0c15	150
5260325f	151	if ((len = RSA_private_decrypt(ilen, inbuf, outbuf, key,
	152	RSA_SSLV23_PADDING)) <= 0)
	153	fatal("rsa_private_decrypt() failed");
8efc0c15	154
5260325f	155	BN_bin2bn(outbuf, len, out);
8efc0c15	156
5260325f	157	memset(outbuf, 0, olen);
	158	memset(inbuf, 0, ilen);
	159	xfree(outbuf);
	160	xfree(inbuf);
8efc0c15	161	}
	162
	163	/* Set whether to output verbose messages during key generation. */
	164
	165	void
	166	rsa_set_verbose(int verbose)
	167	{
5260325f	168	rsa_verbose = verbose;
8efc0c15	169	}