CircuitPython

Source code browser

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
/*****************************************************************************
*
*  security.c  - CC3000 Host Driver Implementation.
*  Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
*
*  Redistribution and use in source and binary forms, with or without
*  modification, are permitted provided that the following conditions
*  are met:
*
*    Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
*
*    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.
*
*    Neither the name of Texas Instruments Incorporated nor the names of
*    its contributors may be used to endorse or promote products derived
*    from this software without specific prior written permission.
*
*  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
*  "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 COPYRIGHT 
*  OWNER 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.
*
*****************************************************************************/

//*****************************************************************************
//
//! \addtogroup security_api
//! @{
//
//*****************************************************************************

#include "security.h"

#ifndef CC3000_UNENCRYPTED_SMART_CONFIG
// foreward sbox
const UINT8 sbox[256] =   { 
//0     1    2      3     4    5     6     7      8    9     A      B    C     D     E     F
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, //0
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, //1
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, //2
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, //3
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, //4
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, //5
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, //6
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, //7
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, //8
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, //9
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, //A
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, //B
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, //C
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, //D
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, //E
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 }; //F   
// inverse sbox
const UINT8 rsbox[256] =
{ 0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb
, 0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb
, 0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e
, 0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25
, 0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92
, 0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84
, 0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06
, 0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b
, 0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73
, 0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e
, 0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b
, 0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4
, 0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f
, 0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef
, 0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61
, 0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d };
// round constant
const UINT8 Rcon[11] = {
  0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36};


UINT8 expandedKey[176];

//*****************************************************************************
//
//!  expandKey
//!
//!  @param  key          AES128 key - 16 bytes
//!  @param  expandedKey  expanded AES128 key
//!
//!  @return  none
//!
//!  @brief  expend a 16 bytes key for AES128 implementation
//!
//*****************************************************************************

void expandKey(UINT8 *expandedKey, UINT8 *key)
{
  UINT16 ii, buf1;
  for (ii=0;ii<16;ii++)
    expandedKey[ii] = key[ii];
  for (ii=1;ii<11;ii++){
    buf1 = expandedKey[ii*16 - 4];
    expandedKey[ii*16 + 0] = sbox[expandedKey[ii*16 - 3]]^expandedKey[(ii-1)*16 + 0]^Rcon[ii];
    expandedKey[ii*16 + 1] = sbox[expandedKey[ii*16 - 2]]^expandedKey[(ii-1)*16 + 1];
    expandedKey[ii*16 + 2] = sbox[expandedKey[ii*16 - 1]]^expandedKey[(ii-1)*16 + 2];
    expandedKey[ii*16 + 3] = sbox[buf1                  ]^expandedKey[(ii-1)*16 + 3];
    expandedKey[ii*16 + 4] = expandedKey[(ii-1)*16 + 4]^expandedKey[ii*16 + 0];
    expandedKey[ii*16 + 5] = expandedKey[(ii-1)*16 + 5]^expandedKey[ii*16 + 1];
    expandedKey[ii*16 + 6] = expandedKey[(ii-1)*16 + 6]^expandedKey[ii*16 + 2];
    expandedKey[ii*16 + 7] = expandedKey[(ii-1)*16 + 7]^expandedKey[ii*16 + 3];
    expandedKey[ii*16 + 8] = expandedKey[(ii-1)*16 + 8]^expandedKey[ii*16 + 4];
    expandedKey[ii*16 + 9] = expandedKey[(ii-1)*16 + 9]^expandedKey[ii*16 + 5];
    expandedKey[ii*16 +10] = expandedKey[(ii-1)*16 +10]^expandedKey[ii*16 + 6];
    expandedKey[ii*16 +11] = expandedKey[(ii-1)*16 +11]^expandedKey[ii*16 + 7];
    expandedKey[ii*16 +12] = expandedKey[(ii-1)*16 +12]^expandedKey[ii*16 + 8];
    expandedKey[ii*16 +13] = expandedKey[(ii-1)*16 +13]^expandedKey[ii*16 + 9];
    expandedKey[ii*16 +14] = expandedKey[(ii-1)*16 +14]^expandedKey[ii*16 +10];
    expandedKey[ii*16 +15] = expandedKey[(ii-1)*16 +15]^expandedKey[ii*16 +11];
  }
	
}

//*****************************************************************************
//
//!  galois_mul2
//!
//!  @param  value    argument to multiply
//!
//!  @return  multiplied argument
//!
//!  @brief  multiply by 2 in the galois field
//!
//*****************************************************************************

UINT8 galois_mul2(UINT8 value)
{
	if (value>>7)
	{
		value = value << 1;
		return (value^0x1b);
	} else
		return value<<1;
}

//*****************************************************************************
//
//!  aes_encr
//!
//!  @param[in]  expandedKey expanded AES128 key
//!  @param[in/out] state 16 bytes of plain text and cipher text
//!
//!  @return  none
//!
//!  @brief   internal implementation of AES128 encryption.
//!           straight forward aes encryption implementation
//!           first the group of operations
//!          - addRoundKey
//!          - subbytes
//!          - shiftrows
//!          - mixcolums
//!          is executed 9 times, after this addroundkey to finish the 9th 
//!          round, after that the 10th round without mixcolums
//!          no further subfunctions to save cycles for function calls
//!          no structuring with "for (....)" to save cycles.
//!	 
//!
//*****************************************************************************

void aes_encr(UINT8 *state, UINT8 *expandedKey)
{
  UINT8 buf1, buf2, buf3, round;
		
  for (round = 0; round < 9; round ++){
    // addroundkey, sbox and shiftrows
    // row 0
    state[ 0]  = sbox[(state[ 0] ^ expandedKey[(round*16)     ])];
    state[ 4]  = sbox[(state[ 4] ^ expandedKey[(round*16) +  4])];
    state[ 8]  = sbox[(state[ 8] ^ expandedKey[(round*16) +  8])];
    state[12]  = sbox[(state[12] ^ expandedKey[(round*16) + 12])];
    // row 1
    buf1 = state[1] ^ expandedKey[(round*16) + 1];
    state[ 1]  = sbox[(state[ 5] ^ expandedKey[(round*16) +  5])];
    state[ 5]  = sbox[(state[ 9] ^ expandedKey[(round*16) +  9])];
    state[ 9]  = sbox[(state[13] ^ expandedKey[(round*16) + 13])];
    state[13]  = sbox[buf1];
    // row 2
    buf1 = state[2] ^ expandedKey[(round*16) + 2];
    buf2 = state[6] ^ expandedKey[(round*16) + 6];
    state[ 2]  = sbox[(state[10] ^ expandedKey[(round*16) + 10])];
    state[ 6]  = sbox[(state[14] ^ expandedKey[(round*16) + 14])];
    state[10]  = sbox[buf1];
    state[14]  = sbox[buf2];
    // row 3
    buf1 = state[15] ^ expandedKey[(round*16) + 15];
    state[15]  = sbox[(state[11] ^ expandedKey[(round*16) + 11])];
    state[11]  = sbox[(state[ 7] ^ expandedKey[(round*16) +  7])];
    state[ 7]  = sbox[(state[ 3] ^ expandedKey[(round*16) +  3])];
    state[ 3]  = sbox[buf1];
    
    // mixcolums //////////
    // col1
    buf1 = state[0] ^ state[1] ^ state[2] ^ state[3];
    buf2 = state[0];
    buf3 = state[0]^state[1]; buf3=galois_mul2(buf3); state[0] = state[0] ^ buf3 ^ buf1;
    buf3 = state[1]^state[2]; buf3=galois_mul2(buf3); state[1] = state[1] ^ buf3 ^ buf1;
    buf3 = state[2]^state[3]; buf3=galois_mul2(buf3); state[2] = state[2] ^ buf3 ^ buf1;
    buf3 = state[3]^buf2;     buf3=galois_mul2(buf3); state[3] = state[3] ^ buf3 ^ buf1;
    // col2
    buf1 = state[4] ^ state[5] ^ state[6] ^ state[7];
    buf2 = state[4];
    buf3 = state[4]^state[5]; buf3=galois_mul2(buf3); state[4] = state[4] ^ buf3 ^ buf1;
    buf3 = state[5]^state[6]; buf3=galois_mul2(buf3); state[5] = state[5] ^ buf3 ^ buf1;
    buf3 = state[6]^state[7]; buf3=galois_mul2(buf3); state[6] = state[6] ^ buf3 ^ buf1;
    buf3 = state[7]^buf2;     buf3=galois_mul2(buf3); state[7] = state[7] ^ buf3 ^ buf1;
    // col3
    buf1 = state[8] ^ state[9] ^ state[10] ^ state[11];
    buf2 = state[8];
    buf3 = state[8]^state[9];   buf3=galois_mul2(buf3); state[8] = state[8] ^ buf3 ^ buf1;
    buf3 = state[9]^state[10];  buf3=galois_mul2(buf3); state[9] = state[9] ^ buf3 ^ buf1;
    buf3 = state[10]^state[11]; buf3=galois_mul2(buf3); state[10] = state[10] ^ buf3 ^ buf1;
    buf3 = state[11]^buf2;      buf3=galois_mul2(buf3); state[11] = state[11] ^ buf3 ^ buf1;
    // col4
    buf1 = state[12] ^ state[13] ^ state[14] ^ state[15];
    buf2 = state[12];
    buf3 = state[12]^state[13]; buf3=galois_mul2(buf3); state[12] = state[12] ^ buf3 ^ buf1;
    buf3 = state[13]^state[14]; buf3=galois_mul2(buf3); state[13] = state[13] ^ buf3 ^ buf1;
    buf3 = state[14]^state[15]; buf3=galois_mul2(buf3); state[14] = state[14] ^ buf3 ^ buf1;
    buf3 = state[15]^buf2;      buf3=galois_mul2(buf3); state[15] = state[15] ^ buf3 ^ buf1;    
		
  }
  // 10th round without mixcols
  state[ 0]  = sbox[(state[ 0] ^ expandedKey[(round*16)     ])];
  state[ 4]  = sbox[(state[ 4] ^ expandedKey[(round*16) +  4])];
  state[ 8]  = sbox[(state[ 8] ^ expandedKey[(round*16) +  8])];
  state[12]  = sbox[(state[12] ^ expandedKey[(round*16) + 12])];
  // row 1
  buf1 = state[1] ^ expandedKey[(round*16) + 1];
  state[ 1]  = sbox[(state[ 5] ^ expandedKey[(round*16) +  5])];
  state[ 5]  = sbox[(state[ 9] ^ expandedKey[(round*16) +  9])];
  state[ 9]  = sbox[(state[13] ^ expandedKey[(round*16) + 13])];
  state[13]  = sbox[buf1];
  // row 2
  buf1 = state[2] ^ expandedKey[(round*16) + 2];
  buf2 = state[6] ^ expandedKey[(round*16) + 6];
  state[ 2]  = sbox[(state[10] ^ expandedKey[(round*16) + 10])];
  state[ 6]  = sbox[(state[14] ^ expandedKey[(round*16) + 14])];
  state[10]  = sbox[buf1];
  state[14]  = sbox[buf2];
  // row 3
  buf1 = state[15] ^ expandedKey[(round*16) + 15];
  state[15]  = sbox[(state[11] ^ expandedKey[(round*16) + 11])];
  state[11]  = sbox[(state[ 7] ^ expandedKey[(round*16) +  7])];
  state[ 7]  = sbox[(state[ 3] ^ expandedKey[(round*16) +  3])];
  state[ 3]  = sbox[buf1];
  // last addroundkey
  state[ 0]^=expandedKey[160];
  state[ 1]^=expandedKey[161];
  state[ 2]^=expandedKey[162];
  state[ 3]^=expandedKey[163];
  state[ 4]^=expandedKey[164];
  state[ 5]^=expandedKey[165];
  state[ 6]^=expandedKey[166];
  state[ 7]^=expandedKey[167];
  state[ 8]^=expandedKey[168];
  state[ 9]^=expandedKey[169];
  state[10]^=expandedKey[170];
  state[11]^=expandedKey[171];
  state[12]^=expandedKey[172];
  state[13]^=expandedKey[173];
  state[14]^=expandedKey[174]; 
  state[15]^=expandedKey[175];
} 

//*****************************************************************************
//
//!  aes_decr
//!
//!  @param[in]  expandedKey expanded AES128 key
//!  @param[in\out] state 16 bytes of cipher text and plain text
//!
//!  @return  none
//!
//!  @brief   internal implementation of AES128 decryption.
//!           straight forward aes decryption implementation
//!           the order of substeps is the exact reverse of decryption
//!           inverse functions:
//!            - addRoundKey is its own inverse
//!            - rsbox is inverse of sbox
//!            - rightshift instead of leftshift
//!            - invMixColumns = barreto + mixColumns
//!           no further subfunctions to save cycles for function calls
//!           no structuring with "for (....)" to save cycles
//!
//*****************************************************************************

void aes_decr(UINT8 *state, UINT8 *expandedKey)
{
  UINT8 buf1, buf2, buf3;
  INT8 round;
  round = 9;
	
  // initial addroundkey
  state[ 0]^=expandedKey[160];
  state[ 1]^=expandedKey[161];
  state[ 2]^=expandedKey[162];
  state[ 3]^=expandedKey[163];
  state[ 4]^=expandedKey[164];
  state[ 5]^=expandedKey[165];
  state[ 6]^=expandedKey[166];
  state[ 7]^=expandedKey[167];
  state[ 8]^=expandedKey[168];
  state[ 9]^=expandedKey[169];
  state[10]^=expandedKey[170];
  state[11]^=expandedKey[171];
  state[12]^=expandedKey[172];
  state[13]^=expandedKey[173];
  state[14]^=expandedKey[174]; 
  state[15]^=expandedKey[175];
	
  // 10th round without mixcols
  state[ 0]  = rsbox[state[ 0]] ^ expandedKey[(round*16)     ];
  state[ 4]  = rsbox[state[ 4]] ^ expandedKey[(round*16) +  4];
  state[ 8]  = rsbox[state[ 8]] ^ expandedKey[(round*16) +  8];
  state[12]  = rsbox[state[12]] ^ expandedKey[(round*16) + 12];
  // row 1
  buf1 =       rsbox[state[13]] ^ expandedKey[(round*16) +  1];
  state[13]  = rsbox[state[ 9]] ^ expandedKey[(round*16) + 13];
  state[ 9]  = rsbox[state[ 5]] ^ expandedKey[(round*16) +  9];
  state[ 5]  = rsbox[state[ 1]] ^ expandedKey[(round*16) +  5];
  state[ 1]  = buf1;
  // row 2
  buf1 =       rsbox[state[ 2]] ^ expandedKey[(round*16) + 10];
  buf2 =       rsbox[state[ 6]] ^ expandedKey[(round*16) + 14];
  state[ 2]  = rsbox[state[10]] ^ expandedKey[(round*16) +  2];
  state[ 6]  = rsbox[state[14]] ^ expandedKey[(round*16) +  6];
  state[10]  = buf1;
  state[14]  = buf2;
  // row 3
  buf1 =       rsbox[state[ 3]] ^ expandedKey[(round*16) + 15];
  state[ 3]  = rsbox[state[ 7]] ^ expandedKey[(round*16) +  3];
  state[ 7]  = rsbox[state[11]] ^ expandedKey[(round*16) +  7];
  state[11]  = rsbox[state[15]] ^ expandedKey[(round*16) + 11];
  state[15]  = buf1;
	
  for (round = 8; round >= 0; round--){
    // barreto
    //col1
    buf1 = galois_mul2(galois_mul2(state[0]^state[2]));
    buf2 = galois_mul2(galois_mul2(state[1]^state[3]));
    state[0] ^= buf1;     state[1] ^= buf2;    state[2] ^= buf1;    state[3] ^= buf2;
    //col2
    buf1 = galois_mul2(galois_mul2(state[4]^state[6]));
    buf2 = galois_mul2(galois_mul2(state[5]^state[7]));
    state[4] ^= buf1;    state[5] ^= buf2;    state[6] ^= buf1;    state[7] ^= buf2;
    //col3
    buf1 = galois_mul2(galois_mul2(state[8]^state[10]));
    buf2 = galois_mul2(galois_mul2(state[9]^state[11]));
    state[8] ^= buf1;    state[9] ^= buf2;    state[10] ^= buf1;    state[11] ^= buf2;
    //col4
    buf1 = galois_mul2(galois_mul2(state[12]^state[14]));
    buf2 = galois_mul2(galois_mul2(state[13]^state[15]));
    state[12] ^= buf1;    state[13] ^= buf2;    state[14] ^= buf1;    state[15] ^= buf2;
    // mixcolums //////////
    // col1
    buf1 = state[0] ^ state[1] ^ state[2] ^ state[3];
    buf2 = state[0];
    buf3 = state[0]^state[1]; buf3=galois_mul2(buf3); state[0] = state[0] ^ buf3 ^ buf1;
    buf3 = state[1]^state[2]; buf3=galois_mul2(buf3); state[1] = state[1] ^ buf3 ^ buf1;
    buf3 = state[2]^state[3]; buf3=galois_mul2(buf3); state[2] = state[2] ^ buf3 ^ buf1;
    buf3 = state[3]^buf2;     buf3=galois_mul2(buf3); state[3] = state[3] ^ buf3 ^ buf1;
    // col2
    buf1 = state[4] ^ state[5] ^ state[6] ^ state[7];
    buf2 = state[4];
    buf3 = state[4]^state[5]; buf3=galois_mul2(buf3); state[4] = state[4] ^ buf3 ^ buf1;
    buf3 = state[5]^state[6]; buf3=galois_mul2(buf3); state[5] = state[5] ^ buf3 ^ buf1;
    buf3 = state[6]^state[7]; buf3=galois_mul2(buf3); state[6] = state[6] ^ buf3 ^ buf1;
    buf3 = state[7]^buf2;     buf3=galois_mul2(buf3); state[7] = state[7] ^ buf3 ^ buf1;
    // col3
    buf1 = state[8] ^ state[9] ^ state[10] ^ state[11];
    buf2 = state[8];
    buf3 = state[8]^state[9];   buf3=galois_mul2(buf3); state[8] = state[8] ^ buf3 ^ buf1;
    buf3 = state[9]^state[10];  buf3=galois_mul2(buf3); state[9] = state[9] ^ buf3 ^ buf1;
    buf3 = state[10]^state[11]; buf3=galois_mul2(buf3); state[10] = state[10] ^ buf3 ^ buf1;
    buf3 = state[11]^buf2;      buf3=galois_mul2(buf3); state[11] = state[11] ^ buf3 ^ buf1;
    // col4
    buf1 = state[12] ^ state[13] ^ state[14] ^ state[15];
    buf2 = state[12];
    buf3 = state[12]^state[13]; buf3=galois_mul2(buf3); state[12] = state[12] ^ buf3 ^ buf1;
    buf3 = state[13]^state[14]; buf3=galois_mul2(buf3); state[13] = state[13] ^ buf3 ^ buf1;
    buf3 = state[14]^state[15]; buf3=galois_mul2(buf3); state[14] = state[14] ^ buf3 ^ buf1;
    buf3 = state[15]^buf2;      buf3=galois_mul2(buf3); state[15] = state[15] ^ buf3 ^ buf1;    
		
    // addroundkey, rsbox and shiftrows
    // row 0
    state[ 0]  = rsbox[state[ 0]] ^ expandedKey[(round*16)     ];
    state[ 4]  = rsbox[state[ 4]] ^ expandedKey[(round*16) +  4];
    state[ 8]  = rsbox[state[ 8]] ^ expandedKey[(round*16) +  8];
    state[12]  = rsbox[state[12]] ^ expandedKey[(round*16) + 12];
    // row 1
    buf1 =       rsbox[state[13]] ^ expandedKey[(round*16) +  1];
    state[13]  = rsbox[state[ 9]] ^ expandedKey[(round*16) + 13];
    state[ 9]  = rsbox[state[ 5]] ^ expandedKey[(round*16) +  9];
    state[ 5]  = rsbox[state[ 1]] ^ expandedKey[(round*16) +  5];
    state[ 1]  = buf1;
    // row 2
    buf1 =       rsbox[state[ 2]] ^ expandedKey[(round*16) + 10];
    buf2 =       rsbox[state[ 6]] ^ expandedKey[(round*16) + 14];
    state[ 2]  = rsbox[state[10]] ^ expandedKey[(round*16) +  2];
    state[ 6]  = rsbox[state[14]] ^ expandedKey[(round*16) +  6];
    state[10]  = buf1;
    state[14]  = buf2;
    // row 3
    buf1 =       rsbox[state[ 3]] ^ expandedKey[(round*16) + 15];
    state[ 3]  = rsbox[state[ 7]] ^ expandedKey[(round*16) +  3];
    state[ 7]  = rsbox[state[11]] ^ expandedKey[(round*16) +  7];
    state[11]  = rsbox[state[15]] ^ expandedKey[(round*16) + 11];
    state[15]  = buf1;
  }
	
} 

//*****************************************************************************
//
//!  aes_encrypt
//!
//!  @param[in]  key   AES128 key of size 16 bytes
//!  @param[in\out] state   16 bytes of plain text and cipher text
//!
//!  @return  none
//!
//!  @brief   AES128 encryption:
//!           Given AES128 key and  16 bytes plain text, cipher text of 16 bytes
//!           is computed. The AES implementation is in mode ECB (Electronic 
//!           Code Book). 
//!	 
//!
//*****************************************************************************

void aes_encrypt(UINT8 *state, UINT8 *key)
{
	// expand the key into 176 bytes
	expandKey(expandedKey, key);       
	aes_encr(state, expandedKey);
}

//*****************************************************************************
//
//!  aes_decrypt
//!
//!  @param[in]  key   AES128 key of size 16 bytes
//!  @param[in\out] state   16 bytes of cipher text and plain text
//!
//!  @return  none
//!
//!  @brief   AES128 decryption:
//!           Given AES128 key and  16 bytes cipher text, plain text of 16 bytes
//!           is computed The AES implementation is in mode ECB 
//!           (Electronic Code Book).
//!	 
//!
//*****************************************************************************

void aes_decrypt(UINT8 *state, UINT8 *key)
{
    expandKey(expandedKey, key);       // expand the key into 176 bytes
    aes_decr(state, expandedKey);
}

//*****************************************************************************
//
//!  aes_read_key
//!
//!  @param[out]  key   AES128 key of size 16 bytes
//!
//!  @return  on success 0, error otherwise.
//!
//!  @brief   Reads AES128 key from EEPROM
//!           Reads the AES128 key from fileID #12 in EEPROM
//!           returns an error if the key does not exist. 
//!	 
//!
//*****************************************************************************

INT32 aes_read_key(UINT8 *key)
{
	INT32	returnValue;
	
	returnValue = nvmem_read(NVMEM_AES128_KEY_FILEID, AES128_KEY_SIZE, 0, key);

	return returnValue;
}

//*****************************************************************************
//
//!  aes_write_key
//!
//!  @param[out]  key   AES128 key of size 16 bytes
//!
//!  @return  on success 0, error otherwise.
//!
//!  @brief   writes AES128 key from EEPROM
//!           Writes the AES128 key to fileID #12 in EEPROM
//!	 
//!
//*****************************************************************************

INT32 aes_write_key(UINT8 *key)
{
	INT32	returnValue;

	returnValue = nvmem_write(NVMEM_AES128_KEY_FILEID, AES128_KEY_SIZE, 0, key);

	return returnValue;
}

#endif //CC3000_UNENCRYPTED_SMART_CONFIG

//*****************************************************************************
//
// Close the Doxygen group.
//! @}
//
//*****************************************************************************