xref: /freebsd/usr.bin/newkey/generic.c (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
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
33 static 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 #include <sys/file.h>
43 
44 #include <rpc/rpc.h>
45 #include <rpc/key_prot.h>
46 
47 #include <mp.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 
51 #include "extern.h"
52 
53 static void adjust(char[HEXKEYBYTES + 1], char *);
54 static void getseed(char *, int, unsigned char *);
55 
56 /*
57  * Generate a seed
58  */
59 static void
60 getseed(char *seed, int seedsize, unsigned char *pass)
61 {
62 	int i;
63 
64 	for (i = 0; i < seedsize; i++) {
65 		seed[i] = (arc4random() & 0xff) ^ pass[i % 8];
66 	}
67 }
68 
69 /*
70  * Generate a random public/secret key pair
71  */
72 void
73 genkeys(char *public, char *secret, char *pass)
74 {
75 	unsigned int i;
76 
77 #   define BASEBITS (8*sizeof (short) - 1)
78 #	define BASE		(1 << BASEBITS)
79 
80 	MINT *pk = mp_itom(0);
81 	MINT *sk = mp_itom(0);
82 	MINT *tmp;
83 	MINT *base = mp_itom((short)BASE);
84 	MINT *root = mp_itom(PROOT);
85 	MINT *modulus = mp_xtom(HEXMODULUS);
86 	short r;
87 	unsigned short seed[KEYSIZE/BASEBITS + 1];
88 	char *xkey;
89 
90 	getseed((char *)seed, sizeof (seed), (u_char *)pass);
91 	for (i = 0; i < KEYSIZE/BASEBITS + 1; i++) {
92 		r = seed[i] % BASE;
93 		tmp = mp_itom(r);
94 		mp_mult(sk, base, sk);
95 		mp_madd(sk, tmp, sk);
96 		mp_mfree(tmp);
97 	}
98 	tmp = mp_itom(0);
99 	mp_mdiv(sk, modulus, tmp, sk);
100 	mp_mfree(tmp);
101 	mp_pow(root, sk, modulus, pk);
102 	xkey = mp_mtox(sk);
103 	adjust(secret, xkey);
104 	xkey = mp_mtox(pk);
105 	adjust(public, xkey);
106 	mp_mfree(sk);
107 	mp_mfree(base);
108 	mp_mfree(pk);
109 	mp_mfree(root);
110 	mp_mfree(modulus);
111 }
112 
113 /*
114  * Adjust the input key so that it is 0-filled on the left
115  */
116 static void
117 adjust(char keyout[HEXKEYBYTES+1], char *keyin)
118 {
119 	char *p;
120 	char *s;
121 
122 	for (p = keyin; *p; p++)
123 		;
124 	for (s = keyout + HEXKEYBYTES; p >= keyin; p--, s--) {
125 		*s = *p;
126 	}
127 	while (s >= keyout) {
128 		*s-- = '0';
129 	}
130 }
131