code / widevine-mirrored-source / 66427ffa50c9a1038998509907e91d0be9ced12a / . / openssl-1.0.0a / crypto / idea / i_skey.c

/* 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(IDEA_KEY_SCHEDULE *ek, IDEA_KEY_SCHEDULE *dk) | |

{ | |

int r; | |

register IDEA_INT *fp,*tp,t; | |

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); | |

} |