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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 "rotate64.h"
26 #include "keccak.h"
27
28 #ifdef DEBUG
29 #  undef DEBUG
30 #endif
31
32 #define DEBUG 0
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 /*
65 static uint64_t rc[] PROGMEM = {
66        0x0000000000000001LL, 0x0000000000008082LL,
67        0x800000000000808ALL, 0x8000000080008000LL,
68        0x000000000000808BLL, 0x0000000080000001LL,
69        0x8000000080008081LL, 0x8000000000008009LL,
70        0x000000000000008ALL, 0x0000000000000088LL,
71        0x0000000080008009LL, 0x000000008000000ALL,
72        0x000000008000808BLL, 0x800000000000008BLL,
73        0x8000000000008089LL, 0x8000000000008003LL,
74        0x8000000000008002LL, 0x8000000000000080LL,
75        0x000000000000800ALL, 0x800000008000000ALL,
76        0x8000000080008081LL, 0x8000000000008080LL,
77        0x0000000080000001LL, 0x8000000080008008LL
78 };
79 */
80
81 static uint8_t rc_comp[] PROGMEM = {
82                 0x01, 0x92, 0xda, 0x70,
83                 0x9b, 0x21, 0xf1, 0x59,
84                 0x8a, 0x88, 0x39, 0x2a,
85                 0xbb, 0xcb, 0xd9, 0x53,
86                 0x52, 0xc0, 0x1a, 0x6a,
87                 0xf1, 0xd0, 0x21, 0x78,
88 };
89
90 static uint8_t r[5][5] PROGMEM = {
91                 { ROT_CODE( 0), ROT_CODE(36), ROT_CODE( 3), ROT_CODE(41), ROT_CODE(18) },
92                 { ROT_CODE( 1), ROT_CODE(44), ROT_CODE(10), ROT_CODE(45), ROT_CODE( 2) },
93                 { ROT_CODE(62), ROT_CODE( 6), ROT_CODE(43), ROT_CODE(15), ROT_CODE(61) },
94                 { ROT_CODE(28), ROT_CODE(55), ROT_CODE(25), ROT_CODE(21), ROT_CODE(56) },
95                 { ROT_CODE(27), ROT_CODE(20), ROT_CODE(39), ROT_CODE( 8), ROT_CODE(14) }
96 };
97
98 static inline
99 void keccak_round(uint64_t a[5][5], uint8_t rci){
100         uint64_t b[5][5];
101         uint8_t i,j;
102         union {
103                         uint64_t v64;
104                         uint8_t v8[8];
105                 } t;
106         /* theta */
107         for(i=0; i<5; ++i){
108                 b[i][0] = a[0][i] ^ a[1][i] ^ a[2][i] ^ a[3][i] ^ a[4][i];
109         }
110         for(i=0; i<5; ++i){
111                 t.v64 = b[(4+i)%5][0] ^ rotate64_1bit_left(b[(i+1)%5][0]);
112                 for(j=0; j<5; ++j){
113                         a[j][i] ^= t.v64;
114                 }
115         }
116 #if DEBUG
117         cli_putstr_P(PSTR("\r\nAfter theta:"));
118         keccak_dump_state(a);
119 #endif
120         /* rho & pi */
121         for(i=0; i<5; ++i){
122                 for(j=0; j<5; ++j){
123 //                      b[(2*i+3*j)%5][j] = rotl64(a[j][i], pgm_read_byte(&(r[i][j])));
124                         b[(2*i+3*j)%5][j] = rotate64left_code(a[j][i], pgm_read_byte(&(r[i][j])));
125                 }
126         }
127 #if DEBUG
128         cli_putstr_P(PSTR("\r\n--- after rho & pi ---"));
129         keccak_dump_state(a);
130 #endif
131         /* chi */
132         for(i=0; i<5; ++i){
133                 for(j=0; j<5; ++j){
134                         a[j][i] =  b[j][i] ^ ((~(b[j][(i+1)%5]))&(b[j][(i+2)%5]));
135                 }
136         }
137 #if DEBUG
138         cli_putstr_P(PSTR("\r\nAfter chi:"));
139         keccak_dump_state(a);
140 #endif
141         /* iota */
142
143 //      memcpy_P(&t, &(rc_comp[rci]), 8);
144         t.v64 = 0;
145         t.v8[0] = pgm_read_byte(&(rc_comp[rci]));
146         if(t.v8[0]&0x40){
147                 t.v8[7] = 0x80;
148         }
149         if(t.v8[0]&0x20){
150                 t.v8[3] = 0x80;
151         }
152         if(t.v8[0]&0x10){
153                 t.v8[1] = 0x80;
154         }
155         t.v8[0] &= 0x8F;
156
157         a[0][0] ^= t.v64;
158 #if DEBUG
159         cli_putstr_P(PSTR("\r\nAfter iota:"));
160         keccak_dump_state(a);
161 #endif
162 }
163
164 void keccak_f1600(uint64_t a[5][5]){
165         uint8_t i=0;
166         do{
167 #if DEBUG
168                 cli_putstr_P(PSTR("\r\n\r\n--- Round "));
169                 cli_hexdump(&i, 1);
170                 cli_putstr_P(PSTR(" ---"));
171 #endif
172                 keccak_round(a, i);
173         }while(++i<24);
174 }
175
176 void keccak_nextBlock(keccak_ctx_t* ctx, const void* block){
177         memxor(ctx->a, block, ctx->bs);
178         keccak_f1600(ctx->a);
179 }
180
181 void keccak_lastBlock(keccak_ctx_t* ctx, const void* block, uint16_t length_b){
182         while(length_b>=ctx->r){
183                 keccak_nextBlock(ctx, block);
184                 block = (uint8_t*)block + ctx->bs;
185                 length_b -=  ctx->r;
186         }
187         uint8_t tmp[ctx->bs];
188         uint8_t pad[3];
189         memset(tmp, 0x00, ctx->bs);
190         memcpy(tmp, block, (length_b+7)/8);
191         /* appand 1 */
192         if(length_b&7){
193                 /* we have some single bits */
194                 uint8_t t;
195                 t = tmp[length_b/8]>>(8-(length_b&7));
196                 t |= 0x01<<(length_b&7);
197                 tmp[length_b/8] = t;
198         }else{
199                 tmp[length_b/8] = 0x01;
200         }
201         pad[0] = ctx->d;
202         pad[1] = ctx->bs;
203         pad[2] = 0x01;
204         if(length_b/8+1+3<=ctx->bs){
205                 memcpy(tmp+length_b/8+1, pad, 3);
206         }else{
207                 if(length_b/8+1+2<=ctx->bs){
208                         memcpy(tmp+length_b/8+1, pad, 2);
209                         keccak_nextBlock(ctx, tmp);
210                         memset(tmp, 0x00, ctx->bs);
211                         tmp[0]=0x01;
212                 }else{
213                         if(length_b/8+1+1<=ctx->bs){
214                                 memcpy(tmp+length_b/8+1, pad, 1);
215                                 keccak_nextBlock(ctx, tmp);
216                                 memset(tmp, 0x00, ctx->bs);
217                                 tmp[0] = ctx->bs;
218                                 tmp[1] = 0x01;
219                         }else{
220                                 keccak_nextBlock(ctx, tmp);
221                                 memset(tmp, 0x00, ctx->bs);
222                                 tmp[0] = ctx->d;
223                                 tmp[1] = ctx->bs;
224                                 tmp[2] = 0x01;
225                         }
226                 }
227         }
228         keccak_nextBlock(ctx, tmp);
229 }
230
231 void keccak_ctx2hash(void* dest, uint16_t length_b, keccak_ctx_t* ctx){
232         while(length_b>=ctx->r){
233                 memcpy(dest, ctx->a, ctx->bs);
234                 dest = (uint8_t*)dest + ctx->bs;
235                 length_b -= ctx->r;
236                 keccak_f1600(ctx->a);
237         }
238         memcpy(dest, ctx->a, (length_b+7)/8);
239 }
240
241 void keccak224_ctx2hash(void* dest, keccak_ctx_t* ctx){
242         keccak_ctx2hash(dest, 224, ctx);
243 }
244
245 void keccak256_ctx2hash(void* dest, keccak_ctx_t* ctx){
246         keccak_ctx2hash(dest, 256, ctx);
247 }
248
249 void keccak384_ctx2hash(void* dest, keccak_ctx_t* ctx){
250         keccak_ctx2hash(dest, 384, ctx);
251 }
252
253 void keccak512_ctx2hash(void* dest, keccak_ctx_t* ctx){
254         keccak_ctx2hash(dest, 512, ctx);
255 }
256
257 /*
258 1. SHA3-224: ⌊Keccak[r = 1152, c = 448, d = 28]⌋224
259 2. SHA3-256: ⌊Keccak[r = 1088, c = 512, d = 32]⌋256
260 3. SHA3-384: ⌊Keccak[r = 832, c = 768, d = 48]⌋384
261 4. SHA3-512: ⌊Keccak[r = 576, c = 1024, d = 64]⌋512
262 */
263 void keccak_init(uint16_t r, uint16_t c, uint8_t d, keccak_ctx_t* ctx){
264         memset(ctx->a, 0x00, 5*5*8);
265         ctx->r = r;
266         ctx->c = c;
267         ctx->d = d;
268         ctx->bs = (uint8_t)(r/8);
269 }
270
271 void keccak224_init(keccak_ctx_t* ctx){
272         keccak_init(1152, 448, 28, ctx);
273 }
274
275 void keccak256_init(keccak_ctx_t* ctx){
276         keccak_init(1088, 512, 32, ctx);
277 }
278
279 void keccak384_init(keccak_ctx_t* ctx){
280         keccak_init( 832, 768, 48, ctx);
281 }
282
283 void keccak512_init(keccak_ctx_t* ctx){
284         keccak_init( 576, 1024, 64, ctx);
285 }