xref: /dragonfly/crypto/libressl/crypto/bf/bf_ofb64.c (revision 72c33676)
1 /* $OpenBSD: bf_ofb64.c,v 1.5 2014/10/28 07:35:58 jsg Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 #include <openssl/blowfish.h>
60 #include "bf_locl.h"
61 
62 /* The input and output encrypted as though 64bit ofb mode is being
63  * used.  The extra state information to record how much of the
64  * 64bit block we have used is contained in *num;
65  */
BF_ofb64_encrypt(const unsigned char * in,unsigned char * out,long length,const BF_KEY * schedule,unsigned char * ivec,int * num)66 void BF_ofb64_encrypt(const unsigned char *in, unsigned char *out, long length,
67 	     const BF_KEY *schedule, unsigned char *ivec, int *num)
68 	{
69 	BF_LONG v0,v1,t;
70 	int n= *num;
71 	long l=length;
72 	unsigned char d[8];
73 	char *dp;
74 	BF_LONG ti[2];
75 	unsigned char *iv;
76 	int save=0;
77 
78 	iv=(unsigned char *)ivec;
79 	n2l(iv,v0);
80 	n2l(iv,v1);
81 	ti[0]=v0;
82 	ti[1]=v1;
83 	dp=(char *)d;
84 	l2n(v0,dp);
85 	l2n(v1,dp);
86 	while (l--)
87 		{
88 		if (n == 0)
89 			{
90 			BF_encrypt((BF_LONG *)ti,schedule);
91 			dp=(char *)d;
92 			t=ti[0]; l2n(t,dp);
93 			t=ti[1]; l2n(t,dp);
94 			save++;
95 			}
96 		*(out++)= *(in++)^d[n];
97 		n=(n+1)&0x07;
98 		}
99 	if (save)
100 		{
101 		v0=ti[0];
102 		v1=ti[1];
103 		iv=(unsigned char *)ivec;
104 		l2n(v0,iv);
105 		l2n(v1,iv);
106 		}
107 	t=v0=v1=ti[0]=ti[1]=0;
108 	*num=n;
109 	}
110 
111