keccak/keccak.c

   1 /* keecak.c */
   2 /*
   3     This file is part of the AVR-Crypto-Lib.
   4     Copyright (C) 2010 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 #include <stdint.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <avr/pgmspace.h>
  24 #include "memxor.h"
  25 #include "keccak.h"
  26
  27 #ifdef DEBUG
  28 #  undef DEBUG
  29 #endif
  30
  31 #define DEBUG 0
  32
  33
  34 #if DEBUG
  35 #include "cli.h"
  36
  37 void keccak_dump_state(uint64_t a[5][5]){
  38         uint8_t i,j;
  39         for(i=0; i<5; ++i){
  40                 cli_putstr_P(PSTR("\r\n"));
  41                 cli_putc('0'+i);
  42                 cli_putstr_P(PSTR(": "));
  43                 for(j=0; j<5; ++j){
  44                         cli_hexdump_rev(&(a[i][j]), 8);
  45                         cli_putc(' ');
  46                 }
  47         }
  48 }
  49
  50 void keccak_dump_ctx(keccak_ctx_t* ctx){
  51         keccak_dump_state(ctx->a);
  52         cli_putstr_P(PSTR("\r\nDBG: r: "));
  53         cli_hexdump_rev(&(ctx->r), 2);
  54         cli_putstr_P(PSTR("\t c: "));
  55         cli_hexdump_rev(&(ctx->c), 2);
  56         cli_putstr_P(PSTR("\t d: "));
  57         cli_hexdump(&(ctx->d), 1);
  58         cli_putstr_P(PSTR("\t bs: "));
  59         cli_hexdump(&(ctx->bs), 1);
  60 }
  61
  62 #endif
  63
  64 static uint64_t rc[] PROGMEM = {
  65        0x0000000000000001LL, 0x0000000000008082LL,
  66        0x800000000000808ALL, 0x8000000080008000LL,
  67        0x000000000000808BLL, 0x0000000080000001LL,
  68        0x8000000080008081LL, 0x8000000000008009LL,
  69        0x000000000000008ALL, 0x0000000000000088LL,
  70        0x0000000080008009LL, 0x000000008000000ALL,
  71        0x000000008000808BLL, 0x800000000000008BLL,
  72        0x8000000000008089LL, 0x8000000000008003LL,
  73        0x8000000000008002LL, 0x8000000000000080LL,
  74        0x000000000000800ALL, 0x800000008000000ALL,
  75        0x8000000080008081LL, 0x8000000000008080LL,
  76        0x0000000080000001LL, 0x8000000080008008LL
  77 };
  78
  79 uint64_t rotl64(uint64_t a, uint8_t r){
  80          return (a<<r)|(a>>(64-r));
  81 }
  82
  83 static uint8_t r[5][5] PROGMEM = {
  84                 {  0, 36,  3, 41, 18 },
  85                 {  1, 44, 10, 45,  2 },
  86                 { 62,  6, 43, 15, 61 },
  87                 { 28, 55, 25, 21, 56 },
  88                 { 27, 20, 39,  8, 14 }
  89 };
  90
  91 void keccak_round(uint64_t a[5][5], uint8_t rci){
  92         uint64_t b[5][5];
  93         uint8_t i,j;
  94         /* theta */
  95         for(i=0; i<5; ++i){
  96                 b[i][0] = a[0][i] ^ a[1][i] ^ a[2][i] ^ a[3][i] ^ a[4][i];
  97         }
  98         for(i=0; i<5; ++i){
  99                 b[i][1] = b[(4+i)%5][0] ^ rotl64(b[(i+1)%5][0], 1);
 100         }
 101         for(i=0; i<5; ++i){
 102                 for(j=0; j<5; ++j){
 103                         a[j][i] ^= b[i][1];
 104                 }
 105         }
 106 #if DEBUG
 107         cli_putstr_P(PSTR("\r\nAfter theta:"));
 108         keccak_dump_state(a);
 109 #endif
 110         /* rho & pi */
 111         for(i=0; i<5; ++i){
 112                 for(j=0; j<5; ++j){
 113                         b[(2*i+3*j)%5][j] = rotl64(a[j][i], pgm_read_byte(&(r[i][j])));
 114                 }
 115         }
 116 #if DEBUG
 117         cli_putstr_P(PSTR("\r\n--- after rho & pi ---"));
 118         keccak_dump_state(a);
 119 #endif
 120         /* chi */
 121         for(i=0; i<5; ++i){
 122                 for(j=0; j<5; ++j){
 123                         a[j][i] =  b[j][i] ^ ((~(b[j][(i+1)%5]))&(b[j][(i+2)%5]));
 124                 }
 125         }
 126 #if DEBUG
 127         cli_putstr_P(PSTR("\r\nAfter chi:"));
 128         keccak_dump_state(a);
 129 #endif
 130         /* iota */
 131         uint64_t t;
 132         memcpy_P(&t, &(rc[rci]), 8);
 133         a[0][0] ^= t;
 134 #if DEBUG
 135         cli_putstr_P(PSTR("\r\nAfter iota:"));
 136         keccak_dump_state(a);
 137 #endif
 138 }
 139
 140 void keccak_f1600(uint64_t a[5][5]){
 141         uint8_t i=0;
 142         do{
 143 #if DEBUG
 144                 cli_putstr_P(PSTR("\r\n\r\n--- Round "));
 145                 cli_hexdump(&i, 1);
 146                 cli_putstr_P(PSTR(" ---"));
 147 #endif
 148                 keccak_round(a, i);
 149         }while(++i<24);
 150 }
 151
 152 void keccak_nextBlock(keccak_ctx_t* ctx, const void* block){
 153         memxor(ctx->a, block, ctx->bs);
 154         keccak_f1600(ctx->a);
 155 }
 156
 157 void keccak_lastBlock(keccak_ctx_t* ctx, const void* block, uint16_t length_b){
 158         while(length_b>=ctx->r){
 159                 keccak_nextBlock(ctx, block);
 160                 block = (uint8_t*)block + ctx->bs;
 161                 length_b -=  ctx->r;
 162         }
 163         uint8_t tmp[ctx->bs];
 164         uint8_t pad[3];
 165         memset(tmp, 0x00, ctx->bs);
 166         memcpy(tmp, block, (length_b+7)/8);
 167         /* appand 1 */
 168         if(length_b&7){
 169                 /* we have some single bits */
 170                 uint8_t t;
 171                 t = tmp[length_b/8]>>(8-(length_b&7));
 172                 t |= 0x01<<(length_b&7);
 173                 tmp[length_b/8] = t;
 174         }else{
 175                 tmp[length_b/8] = 0x01;
 176         }
 177         pad[0] = ctx->d;
 178         pad[1] = ctx->bs;
 179         pad[2] = 0x01;
 180         if(length_b/8+1+3<ctx->bs){
 181                 memcpy(tmp+length_b/8+1, pad, 3);
 182         }else{
 183                 if(length_b/8+1+2<ctx->bs){
 184                         memcpy(tmp+length_b/8+1, pad, 2);
 185                         keccak_nextBlock(ctx, tmp);
 186                         memset(tmp, 0x00, ctx->bs);
 187                         tmp[0]=0x01;
 188                 }else{
 189                         if(length_b/8+1+1<ctx->bs){
 190                                 memcpy(tmp+length_b/8+1, pad, 1);
 191                                 keccak_nextBlock(ctx, tmp);
 192                                 memset(tmp, 0x00, ctx->bs);
 193                                 tmp[0] = ctx->bs;
 194                                 tmp[1] = 0x01;
 195                         }else{
 196                                 keccak_nextBlock(ctx, tmp);
 197                                 memset(tmp, 0x00, ctx->bs);
 198                                 tmp[0] = ctx->d;
 199                                 tmp[1] = ctx->bs;
 200                                 tmp[2] = 0x01;
 201                         }
 202                 }
 203         }
 204         keccak_nextBlock(ctx, tmp);
 205 }
 206
 207 void keccak_ctx2hash(void* dest, uint16_t length_b, keccak_ctx_t* ctx){
 208         while(length_b>=ctx->r){
 209                 memcpy(dest, ctx->a, ctx->bs);
 210                 dest = (uint8_t*)dest + ctx->bs;
 211                 length_b -= ctx->r;
 212                 keccak_f1600(ctx->a);
 213         }
 214         memcpy(dest, ctx->a, (length_b+7)/8);
 215 }
 216
 217 void keccak224_ctx2hash(void* dest, keccak_ctx_t* ctx){
 218         keccak_ctx2hash(dest, 224, ctx);
 219 }
 220
 221 void keccak256_ctx2hash(void* dest, keccak_ctx_t* ctx){
 222         keccak_ctx2hash(dest, 256, ctx);
 223 }
 224
 225 void keccak384_ctx2hash(void* dest, keccak_ctx_t* ctx){
 226         keccak_ctx2hash(dest, 384, ctx);
 227 }
 228
 229 void keccak512_ctx2hash(void* dest, keccak_ctx_t* ctx){
 230         keccak_ctx2hash(dest, 512, ctx);
 231 }
 232
 233 /*
 234 1. SHA3-224: ⌊Keccak[r = 1152, c = 448, d = 28]⌋224
 235 2. SHA3-256: ⌊Keccak[r = 1088, c = 512, d = 32]⌋256
 236 3. SHA3-384: ⌊Keccak[r = 832, c = 768, d = 48]⌋384
 237 4. SHA3-512: ⌊Keccak[r = 576, c = 1024, d = 64]⌋512
 238 */
 239 void keccak_init(uint16_t r, uint16_t c, uint8_t d, keccak_ctx_t* ctx){
 240         memset(ctx->a, 0x00, 5*5*8);
 241         ctx->r = r;
 242         ctx->c = c;
 243         ctx->d = d;
 244         ctx->bs = (uint8_t)(r/8);
 245 }
 246
 247 void keccak224_init(keccak_ctx_t* ctx){
 248         keccak_init(1152, 448, 28, ctx);
 249 }
 250
 251 void keccak256_init(keccak_ctx_t* ctx){
 252         keccak_init(1088, 512, 32, ctx);
 253 }
 254
 255 void keccak384_init(keccak_ctx_t* ctx){
 256         keccak_init( 832, 768, 48, ctx);
 257 }
 258
 259 void keccak512_init(keccak_ctx_t* ctx){
 260         keccak_init( 576, 1024, 64, ctx);
 261 }