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 /*
  32  * Copyright (C) 1986, Sun Microsystems, Inc.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 #include <sys/file.h>
  37
  38 #include <rpc/rpc.h>
  39 #include <rpc/key_prot.h>
  40
  41 #include <mp.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44
  45 #include "extern.h"
  46
  47 static void adjust(char[HEXKEYBYTES + 1], char *);
  48 static void getseed(char *, int, unsigned char *);
  49
  50 /*
  51  * Generate a seed
  52  */
  53 static void
  54 getseed(char *seed, int seedsize, unsigned char *pass)
  55 {
  56         int i;
  57
  58         for (i = 0; i < seedsize; i++) {
  59                 seed[i] = (arc4random() & 0xff) ^ pass[i % 8];
  60         }
  61 }
  62
  63 /*
  64  * Generate a random public/secret key pair
  65  */
  66 void
  67 genkeys(char *public, char *secret, char *pass)
  68 {
  69         unsigned int i;
  70
  71 #   define BASEBITS (8*sizeof (short) - 1)
  72 #       define BASE             (1 << BASEBITS)
  73
  74         MINT *pk = mp_itom(0);
  75         MINT *sk = mp_itom(0);
  76         MINT *tmp;
  77         MINT *base = mp_itom((short)BASE);
  78         MINT *root = mp_itom(PROOT);
  79         MINT *modulus = mp_xtom(HEXMODULUS);
  80         short r;
  81         unsigned short seed[KEYSIZE/BASEBITS + 1];
  82         char *xkey;
  83
  84         getseed((char *)seed, sizeof (seed), (u_char *)pass);
  85         for (i = 0; i < KEYSIZE/BASEBITS + 1; i++) {
  86                 r = seed[i] % BASE;
  87                 tmp = mp_itom(r);
  88                 mp_mult(sk, base, sk);
  89                 mp_madd(sk, tmp, sk);
  90                 mp_mfree(tmp);
  91         }
  92         tmp = mp_itom(0);
  93         mp_mdiv(sk, modulus, tmp, sk);
  94         mp_mfree(tmp);
  95         mp_pow(root, sk, modulus, pk);
  96         xkey = mp_mtox(sk);
  97         adjust(secret, xkey);
  98         xkey = mp_mtox(pk);
  99         adjust(public, xkey);
 100         mp_mfree(sk);
 101         mp_mfree(base);
 102         mp_mfree(pk);
 103         mp_mfree(root);
 104         mp_mfree(modulus);
 105 }
 106
 107 /*
 108  * Adjust the input key so that it is 0-filled on the left
 109  */
 110 static void
 111 adjust(char keyout[HEXKEYBYTES+1], char *keyin)
 112 {
 113         char *p;
 114         char *s;
 115
 116         for (p = keyin; *p; p++)
 117                 ;
 118         for (s = keyout + HEXKEYBYTES; p >= keyin; p--, s--) {
 119                 *s = *p;
 120         }
 121         while (s >= keyout) {
 122                 *s-- = '0';
 123         }
 124 }