openssl/crypto/rc5/rc5_enc.c
1998-12-21 10:56:39 +00:00

223 lines
5.9 KiB
C

/* crypto/rc5/rc5_enc.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <stdio.h>
#include "rc5.h"
#include "rc5_locl.h"
void RC5_32_cbc_encrypt(in, out, length, ks, iv, encrypt)
unsigned char *in;
unsigned char *out;
long length;
RC5_32_KEY *ks;
unsigned char *iv;
int encrypt;
{
register unsigned long tin0,tin1;
register unsigned long tout0,tout1,xor0,xor1;
register long l=length;
unsigned long tin[2];
if (encrypt)
{
c2l(iv,tout0);
c2l(iv,tout1);
iv-=8;
for (l-=8; l>=0; l-=8)
{
c2l(in,tin0);
c2l(in,tin1);
tin0^=tout0;
tin1^=tout1;
tin[0]=tin0;
tin[1]=tin1;
RC5_32_encrypt(tin,ks);
tout0=tin[0]; l2c(tout0,out);
tout1=tin[1]; l2c(tout1,out);
}
if (l != -8)
{
c2ln(in,tin0,tin1,l+8);
tin0^=tout0;
tin1^=tout1;
tin[0]=tin0;
tin[1]=tin1;
RC5_32_encrypt(tin,ks);
tout0=tin[0]; l2c(tout0,out);
tout1=tin[1]; l2c(tout1,out);
}
l2c(tout0,iv);
l2c(tout1,iv);
}
else
{
c2l(iv,xor0);
c2l(iv,xor1);
iv-=8;
for (l-=8; l>=0; l-=8)
{
c2l(in,tin0); tin[0]=tin0;
c2l(in,tin1); tin[1]=tin1;
RC5_32_decrypt(tin,ks);
tout0=tin[0]^xor0;
tout1=tin[1]^xor1;
l2c(tout0,out);
l2c(tout1,out);
xor0=tin0;
xor1=tin1;
}
if (l != -8)
{
c2l(in,tin0); tin[0]=tin0;
c2l(in,tin1); tin[1]=tin1;
RC5_32_decrypt(tin,ks);
tout0=tin[0]^xor0;
tout1=tin[1]^xor1;
l2cn(tout0,tout1,out,l+8);
xor0=tin0;
xor1=tin1;
}
l2c(xor0,iv);
l2c(xor1,iv);
}
tin0=tin1=tout0=tout1=xor0=xor1=0;
tin[0]=tin[1]=0;
}
void RC5_32_encrypt(d,key)
unsigned long *d;
RC5_32_KEY *key;
{
RC5_32_INT a,b,*s;
s=key->data;
a=d[0]+s[0];
b=d[1]+s[1];
E_RC5_32(a,b,s, 2);
E_RC5_32(a,b,s, 4);
E_RC5_32(a,b,s, 6);
E_RC5_32(a,b,s, 8);
E_RC5_32(a,b,s,10);
E_RC5_32(a,b,s,12);
E_RC5_32(a,b,s,14);
E_RC5_32(a,b,s,16);
if (key->rounds == 12)
{
E_RC5_32(a,b,s,18);
E_RC5_32(a,b,s,20);
E_RC5_32(a,b,s,22);
E_RC5_32(a,b,s,24);
}
else if (key->rounds == 16)
{
/* Do a full expansion to avoid a jump */
E_RC5_32(a,b,s,18);
E_RC5_32(a,b,s,20);
E_RC5_32(a,b,s,22);
E_RC5_32(a,b,s,24);
E_RC5_32(a,b,s,26);
E_RC5_32(a,b,s,28);
E_RC5_32(a,b,s,30);
E_RC5_32(a,b,s,32);
}
d[0]=a;
d[1]=b;
}
void RC5_32_decrypt(d,key)
unsigned long *d;
RC5_32_KEY *key;
{
RC5_32_INT a,b,*s;
s=key->data;
a=d[0];
b=d[1];
if (key->rounds == 16)
{
D_RC5_32(a,b,s,32);
D_RC5_32(a,b,s,30);
D_RC5_32(a,b,s,28);
D_RC5_32(a,b,s,26);
/* Do a full expansion to avoid a jump */
D_RC5_32(a,b,s,24);
D_RC5_32(a,b,s,22);
D_RC5_32(a,b,s,20);
D_RC5_32(a,b,s,18);
}
else if (key->rounds == 12)
{
D_RC5_32(a,b,s,24);
D_RC5_32(a,b,s,22);
D_RC5_32(a,b,s,20);
D_RC5_32(a,b,s,18);
}
D_RC5_32(a,b,s,16);
D_RC5_32(a,b,s,14);
D_RC5_32(a,b,s,12);
D_RC5_32(a,b,s,10);
D_RC5_32(a,b,s, 8);
D_RC5_32(a,b,s, 6);
D_RC5_32(a,b,s, 4);
D_RC5_32(a,b,s, 2);
d[0]=a-s[0];
d[1]=b-s[1];
}