"SfR Fresh" - the SfR Freeware/Shareware Archive

Member "pms-0.94/library/blowfish/bf_ofb64.c" of archive pms-0.94.tar.gz:

    1 /* crypto/bf/bf_ofb64.c */
    2 /* Copyright (C) 1995-1997 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 "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  */
   66 void BF_ofb64_encrypt(in, out, length, schedule, ivec, num)
   67 unsigned char *in;
   68 unsigned char *out;
   69 long length;
   70 BF_KEY *schedule;
   71 unsigned char *ivec;
   72 int *num;
   73 	{
   74 	register BF_LONG v0,v1,t;
   75 	register int n= *num;
   76 	register long l=length;
   77 	unsigned char d[8];
   78 	register char *dp;
   79 	BF_LONG ti[2];
   80 	unsigned char *iv;
   81 	int save=0;
   82 
   83 	iv=(unsigned char *)ivec;
   84 	n2l(iv,v0);
   85 	n2l(iv,v1);
   86 	ti[0]=v0;
   87 	ti[1]=v1;
   88 	dp=(char *)d;
   89 	l2n(v0,dp);
   90 	l2n(v1,dp);
   91 	while (l--)
   92 		{
   93 		if (n == 0)
   94 			{
   95 			BF_encrypt((BF_LONG *)ti,schedule);
   96 			dp=(char *)d;
   97 			t=ti[0]; l2n(t,dp);
   98 			t=ti[1]; l2n(t,dp);
   99 			save++;
  100 			}
  101 		*(out++)= *(in++)^d[n];
  102 		n=(n+1)&0x07;
  103 		}
  104 	if (save)
  105 		{
  106 		v0=ti[0];
  107 		v1=ti[1];
  108 		iv=(unsigned char *)ivec;
  109 		l2n(v0,iv);
  110 		l2n(v1,iv);
  111 		}
  112 	t=v0=v1=ti[0]=ti[1]=0;
  113 	*num=n;
  114 	}
  115