123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195 |
- /* crypto/des/cfb_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 "e_os.h"
- #include "des_locl.h"
- #include <assert.h>
- /* The input and output are loaded in multiples of 8 bits.
- * What this means is that if you hame numbits=12 and length=2
- * the first 12 bits will be retrieved from the first byte and half
- * the second. The second 12 bits will come from the 3rd and half the 4th
- * byte.
- */
- /* Until Aug 1 2003 this function did not correctly implement CFB-r, so it
- * will not be compatible with any encryption prior to that date. Ben. */
- void DES_cfb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
- long length, DES_key_schedule *schedule, DES_cblock *ivec,
- int enc)
- {
- register DES_LONG d0,d1,v0,v1;
- register unsigned long l=length;
- register int num=numbits/8,n=(numbits+7)/8,i,rem=numbits%8;
- DES_LONG ti[2];
- unsigned char *iv;
- #ifndef L_ENDIAN
- unsigned char ovec[16];
- #else
- unsigned int sh[4];
- unsigned char *ovec=(unsigned char *)sh;
- /* I kind of count that compiler optimizes away this assertioni,*/
- assert (sizeof(sh[0])==4); /* as this holds true for all, */
- /* but 16-bit platforms... */
-
- #endif
- if (numbits<=0 || numbits > 64) return;
- iv = &(*ivec)[0];
- c2l(iv,v0);
- c2l(iv,v1);
- if (enc)
- {
- while (l >= (unsigned long)n)
- {
- l-=n;
- ti[0]=v0;
- ti[1]=v1;
- DES_encrypt1((DES_LONG *)ti,schedule,DES_ENCRYPT);
- c2ln(in,d0,d1,n);
- in+=n;
- d0^=ti[0];
- d1^=ti[1];
- l2cn(d0,d1,out,n);
- out+=n;
- /* 30-08-94 - eay - changed because l>>32 and
- * l<<32 are bad under gcc :-( */
- if (numbits == 32)
- { v0=v1; v1=d0; }
- else if (numbits == 64)
- { v0=d0; v1=d1; }
- else
- {
- #ifndef L_ENDIAN
- iv=&ovec[0];
- l2c(v0,iv);
- l2c(v1,iv);
- l2c(d0,iv);
- l2c(d1,iv);
- #else
- sh[0]=v0, sh[1]=v1, sh[2]=d0, sh[3]=d1;
- #endif
- if (rem==0)
- memmove(ovec,ovec+num,8);
- else
- for(i=0 ; i < 8 ; ++i)
- ovec[i]=ovec[i+num]<<rem |
- ovec[i+num+1]>>(8-rem);
- #ifdef L_ENDIAN
- v0=sh[0], v1=sh[1];
- #else
- iv=&ovec[0];
- c2l(iv,v0);
- c2l(iv,v1);
- #endif
- }
- }
- }
- else
- {
- while (l >= (unsigned long)n)
- {
- l-=n;
- ti[0]=v0;
- ti[1]=v1;
- DES_encrypt1((DES_LONG *)ti,schedule,DES_ENCRYPT);
- c2ln(in,d0,d1,n);
- in+=n;
- /* 30-08-94 - eay - changed because l>>32 and
- * l<<32 are bad under gcc :-( */
- if (numbits == 32)
- { v0=v1; v1=d0; }
- else if (numbits == 64)
- { v0=d0; v1=d1; }
- else
- {
- #ifndef L_ENDIAN
- iv=&ovec[0];
- l2c(v0,iv);
- l2c(v1,iv);
- l2c(d0,iv);
- l2c(d1,iv);
- #else
- sh[0]=v0, sh[1]=v1, sh[2]=d0, sh[3]=d1;
- #endif
- if (rem==0)
- memmove(ovec,ovec+num,8);
- else
- for(i=0 ; i < 8 ; ++i)
- ovec[i]=ovec[i+num]<<rem |
- ovec[i+num+1]>>(8-rem);
- #ifdef L_ENDIAN
- v0=sh[0], v1=sh[1];
- #else
- iv=&ovec[0];
- c2l(iv,v0);
- c2l(iv,v1);
- #endif
- }
- d0^=ti[0];
- d1^=ti[1];
- l2cn(d0,d1,out,n);
- out+=n;
- }
- }
- iv = &(*ivec)[0];
- l2c(v0,iv);
- l2c(v1,iv);
- v0=v1=d0=d1=ti[0]=ti[1]=0;
- }
|