i_skey.c
上传用户:yisoukefu
上传日期:2020-08-09
资源大小:39506k
文件大小:5k
- /* crypto/idea/i_skey.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 <openssl/idea.h>
- #include "idea_lcl.h"
- static IDEA_INT inverse(unsigned int xin);
- void idea_set_encrypt_key(const unsigned char *key, IDEA_KEY_SCHEDULE *ks)
- {
- int i;
- register IDEA_INT *kt,*kf,r0,r1,r2;
- kt= &(ks->data[0][0]);
- n2s(key,kt[0]); n2s(key,kt[1]); n2s(key,kt[2]); n2s(key,kt[3]);
- n2s(key,kt[4]); n2s(key,kt[5]); n2s(key,kt[6]); n2s(key,kt[7]);
- kf=kt;
- kt+=8;
- for (i=0; i<6; i++)
- {
- r2= kf[1];
- r1= kf[2];
- *(kt++)= ((r2<<9) | (r1>>7))&0xffff;
- r0= kf[3];
- *(kt++)= ((r1<<9) | (r0>>7))&0xffff;
- r1= kf[4];
- *(kt++)= ((r0<<9) | (r1>>7))&0xffff;
- r0= kf[5];
- *(kt++)= ((r1<<9) | (r0>>7))&0xffff;
- r1= kf[6];
- *(kt++)= ((r0<<9) | (r1>>7))&0xffff;
- r0= kf[7];
- *(kt++)= ((r1<<9) | (r0>>7))&0xffff;
- r1= kf[0];
- if (i >= 5) break;
- *(kt++)= ((r0<<9) | (r1>>7))&0xffff;
- *(kt++)= ((r1<<9) | (r2>>7))&0xffff;
- kf+=8;
- }
- }
- void idea_set_decrypt_key(const IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk)
- {
- int r;
- register IDEA_INT *tp,t;
- const IDEA_INT *fp;
- tp= &(dk->data[0][0]);
- fp= &(ek->data[8][0]);
- for (r=0; r<9; r++)
- {
- *(tp++)=inverse(fp[0]);
- *(tp++)=((int)(0x10000L-fp[2])&0xffff);
- *(tp++)=((int)(0x10000L-fp[1])&0xffff);
- *(tp++)=inverse(fp[3]);
- if (r == 8) break;
- fp-=6;
- *(tp++)=fp[4];
- *(tp++)=fp[5];
- }
- tp= &(dk->data[0][0]);
- t=tp[1];
- tp[1]=tp[2];
- tp[2]=t;
- t=tp[49];
- tp[49]=tp[50];
- tp[50]=t;
- }
- /* taken directly from the 'paper' I'll have a look at it later */
- static IDEA_INT inverse(unsigned int xin)
- {
- long n1,n2,q,r,b1,b2,t;
- if (xin == 0)
- b2=0;
- else
- {
- n1=0x10001;
- n2=xin;
- b2=1;
- b1=0;
- do {
- r=(n1%n2);
- q=(n1-r)/n2;
- if (r == 0)
- { if (b2 < 0) b2=0x10001+b2; }
- else
- {
- n1=n2;
- n2=r;
- t=b2;
- b2=b1-q*b2;
- b1=t;
- }
- } while (r != 0);
- }
- return((IDEA_INT)b2);
- }