1*0Sstevel@tonic-gate /* crypto/des/ofb_enc.c */
2*0Sstevel@tonic-gate /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3*0Sstevel@tonic-gate * All rights reserved.
4*0Sstevel@tonic-gate *
5*0Sstevel@tonic-gate * This package is an SSL implementation written
6*0Sstevel@tonic-gate * by Eric Young (eay@cryptsoft.com).
7*0Sstevel@tonic-gate * The implementation was written so as to conform with Netscapes SSL.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * This library is free for commercial and non-commercial use as long as
10*0Sstevel@tonic-gate * the following conditions are aheared to. The following conditions
11*0Sstevel@tonic-gate * apply to all code found in this distribution, be it the RC4, RSA,
12*0Sstevel@tonic-gate * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13*0Sstevel@tonic-gate * included with this distribution is covered by the same copyright terms
14*0Sstevel@tonic-gate * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15*0Sstevel@tonic-gate *
16*0Sstevel@tonic-gate * Copyright remains Eric Young's, and as such any Copyright notices in
17*0Sstevel@tonic-gate * the code are not to be removed.
18*0Sstevel@tonic-gate * If this package is used in a product, Eric Young should be given attribution
19*0Sstevel@tonic-gate * as the author of the parts of the library used.
20*0Sstevel@tonic-gate * This can be in the form of a textual message at program startup or
21*0Sstevel@tonic-gate * in documentation (online or textual) provided with the package.
22*0Sstevel@tonic-gate *
23*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without
24*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions
25*0Sstevel@tonic-gate * are met:
26*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the copyright
27*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer.
28*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright
29*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the
30*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution.
31*0Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software
32*0Sstevel@tonic-gate * must display the following acknowledgement:
33*0Sstevel@tonic-gate * "This product includes cryptographic software written by
34*0Sstevel@tonic-gate * Eric Young (eay@cryptsoft.com)"
35*0Sstevel@tonic-gate * The word 'cryptographic' can be left out if the rouines from the library
36*0Sstevel@tonic-gate * being used are not cryptographic related :-).
37*0Sstevel@tonic-gate * 4. If you include any Windows specific code (or a derivative thereof) from
38*0Sstevel@tonic-gate * the apps directory (application code) you must include an acknowledgement:
39*0Sstevel@tonic-gate * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40*0Sstevel@tonic-gate *
41*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42*0Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43*0Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44*0Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45*0Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46*0Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47*0Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48*0Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49*0Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50*0Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51*0Sstevel@tonic-gate * SUCH DAMAGE.
52*0Sstevel@tonic-gate *
53*0Sstevel@tonic-gate * The licence and distribution terms for any publically available version or
54*0Sstevel@tonic-gate * derivative of this code cannot be changed. i.e. this code cannot simply be
55*0Sstevel@tonic-gate * copied and put under another distribution licence
56*0Sstevel@tonic-gate * [including the GNU Public Licence.]
57*0Sstevel@tonic-gate */
58*0Sstevel@tonic-gate
59*0Sstevel@tonic-gate #include "des_locl.h"
60*0Sstevel@tonic-gate
61*0Sstevel@tonic-gate /* The input and output are loaded in multiples of 8 bits.
62*0Sstevel@tonic-gate * What this means is that if you hame numbits=12 and length=2
63*0Sstevel@tonic-gate * the first 12 bits will be retrieved from the first byte and half
64*0Sstevel@tonic-gate * the second. The second 12 bits will come from the 3rd and half the 4th
65*0Sstevel@tonic-gate * byte.
66*0Sstevel@tonic-gate */
DES_ofb_encrypt(const unsigned char * in,unsigned char * out,int numbits,long length,DES_key_schedule * schedule,DES_cblock * ivec)67*0Sstevel@tonic-gate void DES_ofb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
68*0Sstevel@tonic-gate long length, DES_key_schedule *schedule,
69*0Sstevel@tonic-gate DES_cblock *ivec)
70*0Sstevel@tonic-gate {
71*0Sstevel@tonic-gate register DES_LONG d0,d1,vv0,vv1,v0,v1,n=(numbits+7)/8;
72*0Sstevel@tonic-gate register DES_LONG mask0,mask1;
73*0Sstevel@tonic-gate register long l=length;
74*0Sstevel@tonic-gate register int num=numbits;
75*0Sstevel@tonic-gate DES_LONG ti[2];
76*0Sstevel@tonic-gate unsigned char *iv;
77*0Sstevel@tonic-gate
78*0Sstevel@tonic-gate if (num > 64) return;
79*0Sstevel@tonic-gate if (num > 32)
80*0Sstevel@tonic-gate {
81*0Sstevel@tonic-gate mask0=0xffffffffL;
82*0Sstevel@tonic-gate if (num >= 64)
83*0Sstevel@tonic-gate mask1=mask0;
84*0Sstevel@tonic-gate else
85*0Sstevel@tonic-gate mask1=(1L<<(num-32))-1;
86*0Sstevel@tonic-gate }
87*0Sstevel@tonic-gate else
88*0Sstevel@tonic-gate {
89*0Sstevel@tonic-gate if (num == 32)
90*0Sstevel@tonic-gate mask0=0xffffffffL;
91*0Sstevel@tonic-gate else
92*0Sstevel@tonic-gate mask0=(1L<<num)-1;
93*0Sstevel@tonic-gate mask1=0x00000000L;
94*0Sstevel@tonic-gate }
95*0Sstevel@tonic-gate
96*0Sstevel@tonic-gate iv = &(*ivec)[0];
97*0Sstevel@tonic-gate c2l(iv,v0);
98*0Sstevel@tonic-gate c2l(iv,v1);
99*0Sstevel@tonic-gate ti[0]=v0;
100*0Sstevel@tonic-gate ti[1]=v1;
101*0Sstevel@tonic-gate while (l-- > 0)
102*0Sstevel@tonic-gate {
103*0Sstevel@tonic-gate ti[0]=v0;
104*0Sstevel@tonic-gate ti[1]=v1;
105*0Sstevel@tonic-gate DES_encrypt1((DES_LONG *)ti,schedule,DES_ENCRYPT);
106*0Sstevel@tonic-gate vv0=ti[0];
107*0Sstevel@tonic-gate vv1=ti[1];
108*0Sstevel@tonic-gate c2ln(in,d0,d1,n);
109*0Sstevel@tonic-gate in+=n;
110*0Sstevel@tonic-gate d0=(d0^vv0)&mask0;
111*0Sstevel@tonic-gate d1=(d1^vv1)&mask1;
112*0Sstevel@tonic-gate l2cn(d0,d1,out,n);
113*0Sstevel@tonic-gate out+=n;
114*0Sstevel@tonic-gate
115*0Sstevel@tonic-gate if (num == 32)
116*0Sstevel@tonic-gate { v0=v1; v1=vv0; }
117*0Sstevel@tonic-gate else if (num == 64)
118*0Sstevel@tonic-gate { v0=vv0; v1=vv1; }
119*0Sstevel@tonic-gate else if (num > 32) /* && num != 64 */
120*0Sstevel@tonic-gate {
121*0Sstevel@tonic-gate v0=((v1>>(num-32))|(vv0<<(64-num)))&0xffffffffL;
122*0Sstevel@tonic-gate v1=((vv0>>(num-32))|(vv1<<(64-num)))&0xffffffffL;
123*0Sstevel@tonic-gate }
124*0Sstevel@tonic-gate else /* num < 32 */
125*0Sstevel@tonic-gate {
126*0Sstevel@tonic-gate v0=((v0>>num)|(v1<<(32-num)))&0xffffffffL;
127*0Sstevel@tonic-gate v1=((v1>>num)|(vv0<<(32-num)))&0xffffffffL;
128*0Sstevel@tonic-gate }
129*0Sstevel@tonic-gate }
130*0Sstevel@tonic-gate iv = &(*ivec)[0];
131*0Sstevel@tonic-gate l2c(v0,iv);
132*0Sstevel@tonic-gate l2c(v1,iv);
133*0Sstevel@tonic-gate v0=v1=d0=d1=ti[0]=ti[1]=vv0=vv1=0;
134*0Sstevel@tonic-gate }
135*0Sstevel@tonic-gate
136