1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * CDDL HEADER START
3*0Sstevel@tonic-gate *
4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*0Sstevel@tonic-gate * with the License.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate * and limitations under the License.
13*0Sstevel@tonic-gate *
14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate *
20*0Sstevel@tonic-gate * CDDL HEADER END
21*0Sstevel@tonic-gate */
22*0Sstevel@tonic-gate /* Copyright (c) 1988 AT&T */
23*0Sstevel@tonic-gate /* All Rights Reserved */
24*0Sstevel@tonic-gate
25*0Sstevel@tonic-gate
26*0Sstevel@tonic-gate /*
27*0Sstevel@tonic-gate * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
28*0Sstevel@tonic-gate * Use is subject to license terms.
29*0Sstevel@tonic-gate */
30*0Sstevel@tonic-gate
31*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI"
32*0Sstevel@tonic-gate /*LINTLIBRARY*/
33*0Sstevel@tonic-gate
34*0Sstevel@tonic-gate #include <sys/types.h>
35*0Sstevel@tonic-gate
36*0Sstevel@tonic-gate void
_des_decrypt1(char * block,char * L,char * IP,char * R,char * preS,char * E,char KS[][48],char S[][64],char * f,char * tempL,char * P,char * FP)37*0Sstevel@tonic-gate _des_decrypt1(char *block, char *L, char *IP, char *R, char *preS, char *E, char KS[][48], char S[][64], char *f, char *tempL, char *P, char *FP)
38*0Sstevel@tonic-gate {
39*0Sstevel@tonic-gate /* EXPORT DELETE START */
40*0Sstevel@tonic-gate int i, ii;
41*0Sstevel@tonic-gate int t, j, k;
42*0Sstevel@tonic-gate char t2;
43*0Sstevel@tonic-gate
44*0Sstevel@tonic-gate /*
45*0Sstevel@tonic-gate * First, permute the bits in the input
46*0Sstevel@tonic-gate */
47*0Sstevel@tonic-gate for (j = 0; j < 64; j++)
48*0Sstevel@tonic-gate L[j] = block[IP[j]-1];
49*0Sstevel@tonic-gate /*
50*0Sstevel@tonic-gate * Perform a decryption operation 16 times.
51*0Sstevel@tonic-gate */
52*0Sstevel@tonic-gate for (ii = 0; ii < 16; ii++) {
53*0Sstevel@tonic-gate i = 15-ii;
54*0Sstevel@tonic-gate /*
55*0Sstevel@tonic-gate * Save the R array,
56*0Sstevel@tonic-gate * which will be the new L.
57*0Sstevel@tonic-gate */
58*0Sstevel@tonic-gate for (j = 0; j < 32; j++)
59*0Sstevel@tonic-gate tempL[j] = R[j];
60*0Sstevel@tonic-gate /*
61*0Sstevel@tonic-gate * Expand R to 48 bits using the E selector;
62*0Sstevel@tonic-gate * exclusive-or with the current key bits.
63*0Sstevel@tonic-gate */
64*0Sstevel@tonic-gate for (j = 0; j < 48; j++)
65*0Sstevel@tonic-gate preS[j] = R[E[j]-1] ^ KS[i][j];
66*0Sstevel@tonic-gate /*
67*0Sstevel@tonic-gate * The pre-select bits are now considered
68*0Sstevel@tonic-gate * in 8 groups of 6 bits each.
69*0Sstevel@tonic-gate * The 8 selection functions map these
70*0Sstevel@tonic-gate * 6-bit quantities into 4-bit quantities
71*0Sstevel@tonic-gate * and the results permuted
72*0Sstevel@tonic-gate * to make an f(R, K).
73*0Sstevel@tonic-gate * The indexing into the selection functions
74*0Sstevel@tonic-gate * is peculiar; it could be simplified by
75*0Sstevel@tonic-gate * rewriting the tables.
76*0Sstevel@tonic-gate */
77*0Sstevel@tonic-gate for (j = 0; j < 8; j++) {
78*0Sstevel@tonic-gate t = 6*j;
79*0Sstevel@tonic-gate k = S[j][(preS[t+0]<<5)+
80*0Sstevel@tonic-gate (preS[t+1]<<3)+
81*0Sstevel@tonic-gate (preS[t+2]<<2)+
82*0Sstevel@tonic-gate (preS[t+3]<<1)+
83*0Sstevel@tonic-gate (preS[t+4]<<0)+
84*0Sstevel@tonic-gate (preS[t+5]<<4)];
85*0Sstevel@tonic-gate t = 4*j;
86*0Sstevel@tonic-gate f[t+0] = (k>>3)&01;
87*0Sstevel@tonic-gate f[t+1] = (k>>2)&01;
88*0Sstevel@tonic-gate f[t+2] = (k>>1)&01;
89*0Sstevel@tonic-gate f[t+3] = (k>>0)&01;
90*0Sstevel@tonic-gate }
91*0Sstevel@tonic-gate /*
92*0Sstevel@tonic-gate * The new R is L ^ f(R, K).
93*0Sstevel@tonic-gate * The f here has to be permuted first, though.
94*0Sstevel@tonic-gate */
95*0Sstevel@tonic-gate for (j = 0; j < 32; j++)
96*0Sstevel@tonic-gate R[j] = L[j] ^ f[P[j]-1];
97*0Sstevel@tonic-gate /*
98*0Sstevel@tonic-gate * Finally, the new L (the original R)
99*0Sstevel@tonic-gate * is copied back.
100*0Sstevel@tonic-gate */
101*0Sstevel@tonic-gate for (j = 0; j < 32; j++)
102*0Sstevel@tonic-gate L[j] = tempL[j];
103*0Sstevel@tonic-gate }
104*0Sstevel@tonic-gate /*
105*0Sstevel@tonic-gate * The output L and R are reversed.
106*0Sstevel@tonic-gate */
107*0Sstevel@tonic-gate for (j = 0; j < 32; j++) {
108*0Sstevel@tonic-gate t2 = L[j];
109*0Sstevel@tonic-gate L[j] = R[j];
110*0Sstevel@tonic-gate R[j] = t2;
111*0Sstevel@tonic-gate }
112*0Sstevel@tonic-gate /*
113*0Sstevel@tonic-gate * The final output
114*0Sstevel@tonic-gate * gets the inverse permutation of the very original.
115*0Sstevel@tonic-gate */
116*0Sstevel@tonic-gate for (j = 0; j < 64; j++)
117*0Sstevel@tonic-gate block[j] = L[FP[j]-1];
118*0Sstevel@tonic-gate /* EXPORT DELETE END */
119*0Sstevel@tonic-gate }
120