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 #define W 64
  28
  29 #ifdef DEBUG
  30 #  undef DEBUG
  31 #endif
  32
  33 #define DEBUG 1
  34
  35
  36 #if DEBUG
  37 #include "cli.h"
  38
  39 void keccak_dump_state(uint64_t a[5][5]){
  40         uint8_t i,j;
  41         for(i=0; i<5; ++i){
  42                 cli_putstr_P(PSTR("\r\n"));
  43                 cli_putc('0'+i);
  44                 cli_putstr_P(PSTR(": "));
  45                 for(j=0; j<5; ++j){
  46                         cli_hexdump_rev(&(a[i][j]), 8);
  47                         cli_putc(' ');
  48                 }
  49         }
  50 }
  51
  52 void keccak_dump_ctx(keccak_ctx_t* ctx){
  53         keccak_dump_state(ctx->a);
  54         cli_putstr_P(PSTR("\r\nDBG: r: "));
  55         cli_hexdump_rev(&(ctx->r), 2);
  56         cli_putstr_P(PSTR("\t c: "));
  57         cli_hexdump_rev(&(ctx->c), 2);
  58         cli_putstr_P(PSTR("\t d: "));
  59         cli_hexdump(&(ctx->d), 1);
  60         cli_putstr_P(PSTR("\t bs: "));
  61         cli_hexdump(&(ctx->bs), 1);
  62 }
  63
  64 #endif
  65
  66 #undef DEBUG
  67
  68 static uint64_t rc[] PROGMEM = {
  69        0x0000000000000001LL, 0x0000000000008082LL,
  70        0x800000000000808ALL, 0x8000000080008000LL,
  71        0x000000000000808BLL, 0x0000000080000001LL,
  72        0x8000000080008081LL, 0x8000000000008009LL,
  73        0x000000000000008ALL, 0x0000000000000088LL,
  74        0x0000000080008009LL, 0x000000008000000ALL,
  75        0x000000008000808BLL, 0x800000000000008BLL,
  76        0x8000000000008089LL, 0x8000000000008003LL,
  77        0x8000000000008002LL, 0x8000000000000080LL,
  78        0x000000000000800ALL, 0x800000008000000ALL,
  79        0x8000000080008081LL, 0x8000000000008080LL,
  80        0x0000000080000001LL, 0x8000000080008008LL
  81 };
  82
  83 uint64_t rotl64(uint64_t a, uint8_t r){
  84          return (a<<r)|(a>>(64-r));
  85 }
  86
  87 static uint8_t r[5][5] PROGMEM = {
  88                 {  0, 36,  3, 41, 18 },
  89                 {  1, 44, 10, 45,  2 },
  90                 { 62,  6, 43, 15, 61 },
  91                 { 28, 55, 25, 21, 56 },
  92                 { 27, 20, 39,  8, 14 }
  93 };
  94
  95 void keccak_round(uint64_t a[5][5], uint8_t rci){
  96         uint64_t c[5], d[5], b[5][5];
  97         uint8_t i,j;
  98         /* theta */
  99         for(i=0; i<5; ++i){
 100                 c[i] = a[0][i] ^ a[1][i] ^ a[2][i] ^ a[3][i] ^ a[4][i];
 101         }
 102         for(i=0; i<5; ++i){
 103                 d[i] = c[(4+i)%5] ^ rotl64(c[(i+1)%5], 1);
 104         }
 105         for(i=0; i<5; ++i){
 106                 for(j=0; j<5; ++j){
 107                         a[j][i] ^= d[i];
 108                 }
 109         }
 110 #if DEBUG
 111         cli_putstr_P(PSTR("\r\nAfter theta:"));
 112         keccak_dump_state(a);
 113 #endif
 114         /* rho & pi */
 115         for(i=0; i<5; ++i){
 116                 for(j=0; j<5; ++j){
 117                         b[(2*i+3*j)%5][j] = rotl64(a[j][i], pgm_read_byte(&(r[i][j])));
 118                 }
 119         }
 120 #if DEBUG
 121         cli_putstr_P(PSTR("\r\n--- after rho & pi ---"));
 122         keccak_dump_state(a);
 123 #endif
 124         /* chi */
 125         for(i=0; i<5; ++i){
 126                 for(j=0; j<5; ++j){
 127                         a[j][i] =  b[j][i] ^ ((~(b[j][(i+1)%5]))&(b[j][(i+2)%5]));
 128                 }
 129         }
 130 #if DEBUG
 131         cli_putstr_P(PSTR("\r\nAfter chi:"));
 132         keccak_dump_state(a);
 133 #endif
 134         /* iota */
 135         uint64_t t;
 136         memcpy_P(&t, &(rc[rci]), 8);
 137         a[0][0] ^= t;
 138 #if DEBUG
 139         cli_putstr_P(PSTR("\r\nAfter iota:"));
 140         keccak_dump_state(a);
 141 #endif
 142 }
 143
 144 void keccak_f1600(uint64_t a[5][5]){
 145         uint8_t i=0;
 146         do{
 147 #if DEBUG
 148                 cli_putstr_P(PSTR("\r\n\r\n--- Round "));
 149                 cli_hexdump(&i, 1);
 150                 cli_putstr_P(PSTR(" ---"));
 151 #endif
 152                 keccak_round(a, i);
 153         }while(++i<24);
 154 }
 155
 156 void keccak_nextBlock(keccak_ctx_t* ctx, const void* block){
 157         memxor(ctx->a, block, ctx->bs);
 158         keccak_f1600(ctx->a);
 159 }
 160
 161 void keccak_lastBlock(keccak_ctx_t* ctx, const void* block, uint16_t length_b){
 162         while(length_b>=ctx->r){
 163                 keccak_nextBlock(ctx, block);
 164                 block = (uint8_t*)block + ctx->bs;
 165                 length_b -=  ctx->r;
 166         }
 167         uint8_t tmp[ctx->bs];
 168         uint8_t pad[3];
 169         memset(tmp, 0x00, ctx->bs);
 170         memcpy(tmp, block, (length_b+7)/8);
 171         /* appand 1 */
 172         if(length_b&7){
 173                 /* we have some single bits */
 174                 uint8_t t;
 175                 t = tmp[length_b/8]>>(8-(length_b&7));
 176                 t |= 0x01<<(length_b&7);
 177                 tmp[length_b/8] = t;
 178         }else{
 179                 tmp[length_b/8] = 0x01;
 180         }
 181         pad[0] = ctx->d;
 182         pad[1] = ctx->bs;
 183         pad[2] = 0x01;
 184         if(length_b/8+1+3<ctx->bs){
 185                 memcpy(tmp+length_b/8+1, pad, 3);
 186         }else{
 187                 if(length_b/8+1+2<ctx->bs){
 188                         memcpy(tmp+length_b/8+1, pad, 2);
 189                         keccak_nextBlock(ctx, tmp);
 190                         memset(tmp, 0x00, ctx->bs);
 191                         tmp[0]=0x01;
 192                 }else{
 193                         if(length_b/8+1+1<ctx->bs){
 194                                 memcpy(tmp+length_b/8+1, pad, 1);
 195                                 keccak_nextBlock(ctx, tmp);
 196                                 memset(tmp, 0x00, ctx->bs);
 197                                 tmp[0] = ctx->bs;
 198                                 tmp[1] = 0x01;
 199                         }else{
 200                                 keccak_nextBlock(ctx, tmp);
 201                                 memset(tmp, 0x00, ctx->bs);
 202                                 tmp[0] = ctx->d;
 203                                 tmp[1] = ctx->bs;
 204                                 tmp[2] = 0x01;
 205                         }
 206                 }
 207         }
 208         keccak_nextBlock(ctx, tmp);
 209         keccak_dump_ctx(ctx);
 210 }
 211
 212 void keccak_ctx2hash(void* dest, uint16_t length_b, keccak_ctx_t* ctx){
 213         while(length_b>=ctx->r){
 214                 memcpy(dest, ctx->a, ctx->bs);
 215                 dest = (uint8_t*)dest + ctx->bs;
 216                 length_b -= ctx->r;
 217                 keccak_f1600(ctx->a);
 218         }
 219         memcpy(dest, ctx->a, (length_b+7)/8);
 220 }
 221
 222 void keccak224_ctx2hash(void* dest, keccak_ctx_t* ctx){
 223         keccak_ctx2hash(dest, 224, ctx);
 224 }
 225
 226 void keccak256_ctx2hash(void* dest, keccak_ctx_t* ctx){
 227         keccak_ctx2hash(dest, 256, ctx);
 228 }
 229
 230 void keccak384_ctx2hash(void* dest, keccak_ctx_t* ctx){
 231         keccak_ctx2hash(dest, 384, ctx);
 232 }
 233
 234 void keccak512_ctx2hash(void* dest, keccak_ctx_t* ctx){
 235         keccak_ctx2hash(dest, 512, ctx);
 236 }
 237
 238 /*
 239 1. SHA3-224: ⌊Keccak[r = 1152, c = 448, d = 28]⌋224
 240 2. SHA3-256: ⌊Keccak[r = 1088, c = 512, d = 32]⌋256
 241 3. SHA3-384: ⌊Keccak[r = 832, c = 768, d = 48]⌋384
 242 4. SHA3-512: ⌊Keccak[r = 576, c = 1024, d = 64]⌋512
 243 */
 244 void keccak_init(uint16_t r, uint16_t c, uint8_t d, keccak_ctx_t* ctx){
 245         memset(ctx->a, 0x00, 5*5*8);
 246         ctx->r = r;
 247         ctx->c = c;
 248         ctx->d = d;
 249         ctx->bs = (uint8_t)(r/8);
 250 }
 251
 252 void keccak224_init(keccak_ctx_t* ctx){
 253         keccak_init(1152, 448, 28, ctx);
 254 }
 255
 256 void keccak256_init(keccak_ctx_t* ctx){
 257         keccak_init(1088, 512, 32, ctx);
 258 }
 259
 260 void keccak384_init(keccak_ctx_t* ctx){
 261         keccak_init( 832, 768, 48, ctx);
 262 }
 263
 264 void keccak512_init(keccak_ctx_t* ctx){
 265         keccak_init( 576, 1024, 64, ctx);
 266 }