shabal/shabal.c

   1 /* shabal.c */
   2 /*
   3     This file is part of the AVR-Crypto-Lib.
   4     Copyright (C) 2009  Daniel Otte (daniel.otte@rub.de)
   5
   6     This program is free software: you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation, either version 3 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19 /*
  20  * \file    shabal.c
  21  * \author  Daniel Otte
  22  * \email   daniel.otte@rub.de
  23  * \date    2009-04-17
  24  * \license GPLv3 or later
  25  *
  26  */
  27
  28 #include <stdint.h>
  29 #include "shabal.h"
  30 #include <string.h>
  31
  32 #define SHABAL_O1 13
  33 #define SHABAL_O2  9
  34 #define SHABAL_O3  6
  35
  36
  37 static inline
  38 uint32_t shabal_u(uint32_t a){
  39         return (a<<1)+a; /* a*3 */
  40 }
  41
  42 static inline
  43 uint32_t shabal_v(uint32_t a){
  44         return (a<<2)+a; /* a*5 */
  45 }
  46
  47 #define ROTL32(a,n) (((a)<<(n))|((a)>>(32-(n))))
  48
  49 static
  50 void shabal_p(shabal_ctx_t* ctx, const void* m){
  51         uint8_t i,j;
  52         for(i=0;i<16;++i){
  53                 ctx->b[i] = ROTL32(ctx->b[i],17);
  54         }
  55         for(j=0;j<SHABAL_P;j++){
  56                 for(i=0;i<16;++i){
  57                         ctx->a[(i+j*16)%SHABAL_R] =
  58                                 shabal_u(ctx->a[(i+j*16)%SHABAL_R]
  59                                         ^ shabal_v(ROTL32(ctx->a[(i+j*16+SHABAL_R-1)%SHABAL_R],15))
  60                                     ^ ctx->c[(8-i+16)%16])
  61                                 ^ ctx->b[(i+SHABAL_O1)%16]
  62                                 ^ ((ctx->b[(i+SHABAL_O2)%16]) & ~(ctx->b[(i+SHABAL_O3)%16]))
  63                                 ^ ((uint32_t*)m)[i];
  64                         ctx->b[i] = ROTL32(ctx->b[i], 1) ^ ~(ctx->a[(i+j*16)%SHABAL_R]);
  65                 }
  66         }
  67
  68         for(j=0;j<36;++j){
  69                 ctx->a[j%SHABAL_R] += ctx->c[(j+3)%16];
  70         }
  71 }
  72
  73 void shabal_nextBlock(shabal_ctx_t* ctx, const void* block){
  74         uint8_t i;
  75         uint32_t* t;
  76         for(i=0;i<16;++i){
  77                 ctx->b[i] += ((uint32_t*)block)[i];
  78         }
  79         ctx->a[0] ^= ctx->w.w32[0];
  80         ctx->a[1] ^= ctx->w.w32[1];
  81         shabal_p(ctx, block);
  82         for(i=0;i<16;++i){
  83                 ctx->c[i] -= ((uint32_t*)block)[i];
  84         }
  85         ctx->w.w64++;
  86         t = ctx->c;
  87         ctx->c = ctx->b;
  88         ctx->b = t;
  89 }
  90
  91 void shabal_lastBlock(shabal_ctx_t* ctx, const void* block, uint16_t length_b){
  92         uint8_t i,j;
  93         uint32_t* t;
  94         uint8_t buffer[64];
  95         while(length_b>=SHABAL_BLOCKSIZE){
  96                 shabal_nextBlock(ctx, block);
  97                 block = (uint8_t*)block + SHABAL_BLOCKSIZE_B;
  98                 length_b -= SHABAL_BLOCKSIZE;
  99         }
 100         memset(buffer, 0, 64);
 101         memcpy(buffer, block, (length_b+7)/8);
 102         buffer[length_b/8] |= 0x80>>(length_b%8);
 103
 104         for(i=0;i<16;++i){
 105                 ctx->b[i] += ((uint32_t*)buffer)[i];
 106         }
 107
 108         for(j=0; j<4;++j){
 109                 ctx->a[0] ^= ctx->w.w32[0];
 110                 ctx->a[1] ^= ctx->w.w32[1];
 111                 shabal_p(ctx, buffer);
 112                 t = ctx->c;
 113                 ctx->c = ctx->b;
 114                 ctx->b = t;
 115         }
 116
 117 }
 118
 119 void shabal_ctx2hash(void* dest, const shabal_ctx_t* ctx, uint16_t outlength_b){
 120         memcpy(dest, &(ctx->c[16-outlength_b/32]), outlength_b/8);
 121 }