/usr.bin/newkey/generic.c

  1/*
  2 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  3 * unrestricted use provided that this legend is included on all tape
  4 * media and as a part of the software program in whole or part.  Users
  5 * may copy or modify Sun RPC without charge, but are not authorized
  6 * to license or distribute it to anyone else except as part of a product or
  7 * program developed by the user or with the express written consent of
  8 * Sun Microsystems, Inc.
  9 *
 10 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
 11 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 12 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
 13 *
 14 * Sun RPC is provided with no support and without any obligation on the
 15 * part of Sun Microsystems, Inc. to assist in its use, correction,
 16 * modification or enhancement.
 17 *
 18 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
 19 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
 20 * OR ANY PART THEREOF.
 21 *
 22 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
 23 * or profits or other special, indirect and consequential damages, even if
 24 * Sun has been advised of the possibility of such damages.
 25 *
 26 * Sun Microsystems, Inc.
 27 * 2550 Garcia Avenue
 28 * Mountain View, California  94043
 29 */
 30
 31#if !defined(lint) && defined(SCCSIDS)
 32#if 0
 33static char sccsid[] = "@(#)generic.c 1.2 91/03/11 Copyr 1986 Sun Micro";
 34#endif
 35#endif
 36
 37/*
 38 * Copyright (C) 1986, Sun Microsystems, Inc.
 39 */
 40
 41#include <sys/cdefs.h>
 42__FBSDID("$FreeBSD$");
 43
 44#include <sys/file.h>
 45
 46#include <rpc/rpc.h>
 47#include <rpc/key_prot.h>
 48
 49#include <mp.h>
 50#include <stdio.h>
 51#include <stdlib.h>
 52
 53#include "extern.h"
 54
 55static void adjust(char[], char *);
 56static void getseed(char *, int, unsigned char *);
 57
 58/*
 59 * Generate a seed
 60 */
 61static void
 62getseed(char *seed, int seedsize, unsigned char *pass)
 63{
 64	int i;
 65
 66	for (i = 0; i < seedsize; i++) {
 67		seed[i] = (arc4random() & 0xff) ^ pass[i % 8];
 68	}
 69}
 70
 71/*
 72 * Generate a random public/secret key pair
 73 */
 74void
 75genkeys(char *public, char *secret, char *pass)
 76{
 77	unsigned int i;
 78
 79#   define BASEBITS (8*sizeof (short) - 1)
 80#	define BASE		(1 << BASEBITS)
 81
 82	MINT *pk = mp_itom(0);
 83	MINT *sk = mp_itom(0);
 84	MINT *tmp;
 85	MINT *base = mp_itom(BASE);
 86	MINT *root = mp_itom(PROOT);
 87	MINT *modulus = mp_xtom(HEXMODULUS);
 88	short r;
 89	unsigned short seed[KEYSIZE/BASEBITS + 1];
 90	char *xkey;
 91
 92	getseed((char *)seed, sizeof (seed), (u_char *)pass);
 93	for (i = 0; i < KEYSIZE/BASEBITS + 1; i++) {
 94		r = seed[i] % BASE;
 95		tmp = mp_itom(r);
 96		mp_mult(sk, base, sk);
 97		mp_madd(sk, tmp, sk);
 98		mp_mfree(tmp);
 99	}
100	tmp = mp_itom(0);
101	mp_mdiv(sk, modulus, tmp, sk);
102	mp_mfree(tmp);
103	mp_pow(root, sk, modulus, pk);
104	xkey = mp_mtox(sk);
105	adjust(secret, xkey);
106	xkey = mp_mtox(pk);
107	adjust(public, xkey);
108	mp_mfree(sk);
109	mp_mfree(base);
110	mp_mfree(pk);
111	mp_mfree(root);
112	mp_mfree(modulus);
113}
114
115/*
116 * Adjust the input key so that it is 0-filled on the left
117 */
118static void
119adjust(char keyout[HEXKEYBYTES+1], char *keyin)
120{
121	char *p;
122	char *s;
123
124	for (p = keyin; *p; p++)
125		;
126	for (s = keyout + HEXKEYBYTES; p >= keyin; p--, s--) {
127		*s = *p;
128	}
129	while (s >= keyout) {
130		*s-- = '0';
131	}
132}