aboutsummaryrefslogblamecommitdiff
path: root/src/rtl/aes.v
blob: 2ead578cbded0436f22d72adfaf3779e4d5b3d6d (plain) (tree)
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
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586









































































































































































































































































































































































































































































































































































































                                                                         
//======================================================================
//
// aes.v
// --------
// Top level wrapper for the AES block cipher core.
//
//
// Author: Joachim Strombergson
// Copyright (c) 2014, SUNET
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or
// without modification, are permitted provided that the following
// conditions are met:
//
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//
// 2. 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.
//
// 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.
//
//======================================================================

module aes(
           // Clock and reset.
           input wire           clk,
           input wire           reset_n,

           // Control.
           input wire           cs,
           input wire           we,

           // Data ports.
           input wire  [7 : 0]  address,
           input wire  [31 : 0] write_data,
           output wire [31 : 0] read_data,
           output wire          error
          );

  //----------------------------------------------------------------
  // Internal constant and parameter definitions.
  //----------------------------------------------------------------
  parameter ADDR_NAME0       = 8'h00;
  parameter ADDR_NAME1       = 8'h01;
  parameter ADDR_VERSION     = 8'h02;

  parameter ADDR_CTRL        = 8'h08;
  parameter CTRL_INIT_BIT    = 0;
  parameter CTRL_NEXT_BIT    = 1;

  parameter ADDR_CONFIG      = 8'h09;
  parameter CTRL_ENCDEC_BIT  = 0;
  parameter CTRL_KEYLEN_BIT  = 1;

  parameter ADDR_STATUS      = 8'h0a;
  parameter STATUS_READY_BIT = 0;
  parameter STATUS_VALID_BIT = 1;

  parameter ADDR_KEY0        = 8'h10;
  parameter ADDR_KEY1        = 8'h11;
  parameter ADDR_KEY2        = 8'h12;
  parameter ADDR_KEY3        = 8'h13;
  parameter ADDR_KEY4        = 8'h14;
  parameter ADDR_KEY5        = 8'h15;
  parameter ADDR_KEY6        = 8'h16;
  parameter ADDR_KEY7        = 8'h17;

  parameter ADDR_BLOCK0      = 8'h20;
  parameter ADDR_BLOCK1      = 8'h21;
  parameter ADDR_BLOCK2      = 8'h22;
  parameter ADDR_BLOCK3      = 8'h23;

  parameter ADDR_RESULT0     = 8'h30;
  parameter ADDR_RESULT1     = 8'h31;
  parameter ADDR_RESULT2     = 8'h32;
  parameter ADDR_RESULT3     = 8'h33;

  parameter CORE_NAME0       = 32'h6165732d; // "aes-"
  parameter CORE_NAME1       = 32'h31323820; // "128 "
  parameter CORE_VERSION     = 32'h302e3530; // "0.50"


  //----------------------------------------------------------------
  // Registers including update variables and write enable.
  //----------------------------------------------------------------
  reg init_reg;
  reg init_new;
  reg init_we;
  reg init_set;

  reg next_reg;
  reg next_new;
  reg next_we;
  reg next_set;

  reg encdec_reg;
  reg keylen_reg;
  reg config_we;

  reg [31 : 0] block0_reg;
  reg          block0_we;
  reg [31 : 0] block1_reg;
  reg          block1_we;
  reg [31 : 0] block2_reg;
  reg          block2_we;
  reg [31 : 0] block3_reg;
  reg          block3_we;

  reg [31 : 0] key0_reg;
  reg          key0_we;
  reg [31 : 0] key1_reg;
  reg          key1_we;
  reg [31 : 0] key2_reg;
  reg          key2_we;
  reg [31 : 0] key3_reg;
  reg          key3_we;
  reg [31 : 0] key4_reg;
  reg          key4_we;
  reg [31 : 0] key5_reg;
  reg          key5_we;
  reg [31 : 0] key6_reg;
  reg          key6_we;
  reg [31 : 0] key7_reg;
  reg          key7_we;

  reg [127 : 0] result_reg;
  reg           valid_reg;
  reg           ready_reg;


  //----------------------------------------------------------------
  // Wires.
  //----------------------------------------------------------------
  reg [31 : 0]   tmp_read_data;
  reg            tmp_error;

  wire           core_encdec;
  wire           core_init;
  wire           core_next;
  wire           core_ready;
  wire [255 : 0] core_key;
  wire           core_keylen;
  wire [127 : 0] core_block;
  wire [127 : 0] core_result;
  wire           core_valid;


  //----------------------------------------------------------------
  // Concurrent connectivity for ports etc.
  //----------------------------------------------------------------
  assign read_data = tmp_read_data;
  assign error     = tmp_error;

  assign core_key = {key0_reg, key1_reg, key2_reg, key3_reg,
                     key4_reg, key5_reg, key6_reg, key7_reg};

  assign core_block  = {block0_reg, block1_reg, block2_reg, block3_reg};
  assign core_init   = init_reg;
  assign core_next   = next_reg;
  assign core_encdec = encdec_reg;
  assign core_keylen = keylen_reg;


  //----------------------------------------------------------------
  // core instantiation.
  //----------------------------------------------------------------
  aes_core core(
                .clk(clk),
                .reset_n(reset_n),

                .encdec(core_encdec),
                .init(core_init),
                .next(core_next),
                .ready(core_ready),

                .key(core_key),
                .keylen(core_keylen),

                .block(core_block),
                .result(core_result),
                .result_valid(core_valid)
               );


  //----------------------------------------------------------------
  // reg_update
  // Update functionality for all registers in the core.
  // All registers are positive edge triggered with asynchronous
  // active low reset.
  //----------------------------------------------------------------
  always @ (posedge clk or negedge reset_n)
    begin
      if (!reset_n)
        begin
          block0_reg <= 32'h00000000;
          block1_reg <= 32'h00000000;
          block2_reg <= 32'h00000000;
          block3_reg <= 32'h00000000;

          key0_reg   <= 32'h00000000;
          key1_reg   <= 32'h00000000;
          key2_reg   <= 32'h00000000;
          key3_reg   <= 32'h00000000;
          key4_reg   <= 32'h00000000;
          key5_reg   <= 32'h00000000;
          key6_reg   <= 32'h00000000;
          key7_reg   <= 32'h00000000;

          init_reg   <= 0;
          next_reg   <= 0;
          encdec_reg <= 0;
          keylen_reg <= 0;

          result_reg <= 128'h00000000000000000000000000000000;
          valid_reg  <= 0;
          ready_reg  <= 0;
        end
      else
        begin
          ready_reg      <= core_ready;
          valid_reg      <= core_valid;
          result_reg     <= core_result;

          if (init_we)
            begin
              init_reg <= init_new;
            end

          if (next_we)
            begin
              next_reg <= next_new;
            end

          if (config_we)
            begin
              encdec_reg <= write_data[CTRL_ENCDEC_BIT];
              keylen_reg <= write_data[CTRL_KEYLEN_BIT];
            end

          if (key0_we)
            begin
              key0_reg <= write_data;
            end

          if (key1_we)
            begin
              key1_reg <= write_data;
            end

          if (key2_we)
            begin
              key2_reg <= write_data;
            end

          if (key3_we)
            begin
              key3_reg <= write_data;
            end

          if (key4_we)
            begin
              key4_reg <= write_data;
            end

          if (key5_we)
            begin
              key5_reg <= write_data;
            end

          if (key6_we)
            begin
              key6_reg <= write_data;
            end

          if (key7_we)
            begin
              key7_reg <= write_data;
            end

          if (block0_we)
            begin
              block0_reg <= write_data;
            end

          if (block1_we)
            begin
              block1_reg <= write_data;
            end

          if (block2_we)
            begin
              block2_reg <= write_data;
            end

          if (block3_we)
            begin
              block3_reg <= write_data;
            end
        end
    end // reg_update


  //----------------------------------------------------------------
  // flag_ctrl
  //
  // Logic to set and the automatically reset init- and
  // next flags that has been set.
  //----------------------------------------------------------------
  always @*
    begin : flag_reset
      init_new = 0;
      init_we  = 0;
      next_new = 0;
      next_we  = 0;

      if (init_set)
        begin
          init_new = 1;
          init_we  = 1;
        end
      else if (init_reg)
        begin
          init_new = 0;
          init_we  = 1;
        end

      if (next_set)
        begin
          next_new = 1;
          next_we  = 1;
        end
      else if (next_reg)
        begin
          next_new = 0;
          next_we  = 1;
        end
    end


  //----------------------------------------------------------------
  // api
  //
  // The interface command decoding logic.
  //----------------------------------------------------------------
  always @*
    begin : api
      init_set      = 0;
      next_set      = 0;
      config_we     = 0;
      key0_we       = 0;
      key1_we       = 0;
      key2_we       = 0;
      key3_we       = 0;
      key4_we       = 0;
      key5_we       = 0;
      key6_we       = 0;
      key7_we       = 0;
      block0_we     = 0;
      block1_we     = 0;
      block2_we     = 0;
      block3_we     = 0;
      tmp_read_data = 32'h00000000;
      tmp_error     = 0;

      if (cs)
        begin
          if (we)
            begin
              case (address)
                // Write operations.
                ADDR_CTRL:
                  begin
                    init_set = write_data[CTRL_INIT_BIT];
                    next_set = write_data[CTRL_NEXT_BIT];
                  end

                ADDR_CONFIG:
                  begin
                    config_we = 1;
                  end

                ADDR_KEY0:
                  begin
                    key0_we = 1;
                  end

                ADDR_KEY1:
                  begin
                    key1_we = 1;
                  end

                ADDR_KEY2:
                  begin
                    key2_we = 1;
                  end

                ADDR_KEY3:
                  begin
                    key3_we = 1;
                  end

                ADDR_KEY4:
                  begin
                    key4_we = 1;
                  end

                ADDR_KEY5:
                  begin
                    key5_we = 1;
                  end

                ADDR_KEY6:
                  begin
                    key6_we = 1;
                  end

                ADDR_KEY7:
                  begin
                    key7_we = 1;
                  end

                ADDR_BLOCK0:
                  begin
                    block0_we = 1;
                  end

                ADDR_BLOCK1:
                  begin
                    block1_we = 1;
                  end

                ADDR_BLOCK2:
                  begin
                    block2_we = 1;
                  end

                ADDR_BLOCK3:
                  begin
                    block3_we = 1;
                  end

                default:
                  begin
                    tmp_error = 1;
                  end
              endcase // case (address)
            end // if (we)

          else
            begin
              case (address)
                // Read operations.
                ADDR_NAME0:
                  begin
                    tmp_read_data = CORE_NAME0;
                  end

                ADDR_NAME1:
                  begin
                    tmp_read_data = CORE_NAME1;
                  end

                ADDR_VERSION:
                  begin
                    tmp_read_data = CORE_VERSION;
                  end

                ADDR_CTRL:
                  begin
                    tmp_read_data = {28'h0000000, keylen_reg, encdec_reg,
                                     next_reg, init_reg};
                  end

                ADDR_STATUS:
                  begin
                    tmp_read_data = {30'h00000000, valid_reg, ready_reg};
                  end

                ADDR_KEY0:
                  begin
                    tmp_read_data = key0_reg;
                  end

                ADDR_KEY1:
                  begin
                    tmp_read_data = key1_reg;
                  end

                ADDR_KEY2:
                  begin
                    tmp_read_data = key2_reg;
                  end

                ADDR_KEY3:
                  begin
                    tmp_read_data = key3_reg;
                  end

                ADDR_KEY4:
                  begin
                    tmp_read_data = key4_reg;
                  end

                ADDR_KEY5:
                  begin
                    tmp_read_data = key5_reg;
                  end

                ADDR_KEY6:
                  begin
                    tmp_read_data = key6_reg;
                  end

                ADDR_KEY7:
                  begin
                    tmp_read_data = key7_reg;
                  end

                ADDR_BLOCK0:
                  begin
                    tmp_read_data = block0_reg;
                  end

                ADDR_BLOCK1:
                  begin
                    tmp_read_data = block1_reg;
                  end

                ADDR_BLOCK2:
                  begin
                    tmp_read_data = block2_reg;
                  end

                ADDR_BLOCK3:
                  begin
                    tmp_read_data = block3_reg;
                  end

                ADDR_RESULT0:
                  begin
                    tmp_read_data = result_reg[127 : 96];
                  end

                ADDR_RESULT1:
                  begin
                    tmp_read_data = result_reg[95 : 64];
                  end

                ADDR_RESULT2:
                  begin
                    tmp_read_data = result_reg[63 : 32];
                  end

                ADDR_RESULT3:
                  begin
                    tmp_read_data = result_reg[31 : 0];
                  end

                default:
                  begin
                    tmp_error = 1;
                  end
              endcase // case (address)
            end
        end
    end // addr_decoder
endmodule // aes

//======================================================================
// EOF aes.v
//======================================================================