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////////////////////////////////////////////////////////////////////////
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//// ////
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//// This file is part of the AES SystemVerilog Behavioral ////
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//// Model project ////
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//// http://www.opencores.org/cores/aes_beh_model/ ////
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//// ////
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//// Description ////
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//// Implementation of AES SystemVerilog Behavioral ////
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//// Model according to AES Behavioral Model specification document.////
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//// ////
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//// To Do: ////
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//// - ////
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//// ////
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//// Author(s): ////
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//// - scheng, schengopencores@opencores.org ////
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//// ////
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////////////////////////////////////////////////////////////////////////
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//// ////
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//// Copyright (C) 2009 Authors and OPENCORES.ORG ////
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//// ////
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//// This source file may be used and distributed without ////
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//// restriction provided that this copyright statement is not ////
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//// removed from the file and that any derivative work contains ////
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//// the original copyright notice and the associated disclaimer. ////
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//// ////
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//// This source file is free software; you can redistribute it ////
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//// and/or modify it under the terms of the GNU Lesser General ////
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//// Public License as published by the Free Software Foundation; ////
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//// either version 2.1 of the License, or (at your option) any ////
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//// later version. ////
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//// ////
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//// This source is distributed in the hope that it will be ////
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//// useful, but WITHOUT ANY WARRANTY; without even the implied ////
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//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////
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//// PURPOSE. See the GNU Lesser General Public License for more ////
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//// details. ////
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//// ////
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//// You should have received a copy of the GNU Lesser General ////
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//// Public License along with this source; if not, download it ////
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//// from http://www.opencores.org/lgpl.shtml ////
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//// ////
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////////////////////////////////////////////////////////////////////////
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// This is a SystemVerilog implementation of the AES decryption algorithm
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// described in FIPS-197. Only decryption is implemented in this version.
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// The model is implemented as a SystemVerilog class which can be instantiated
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// in a testbench to generate known good results for verification of AES
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// decryption IPs.
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//
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// Try to use the typdefs at the end of this file instead of the class
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// below while declaring variables for the aes model in your testbench.
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//
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// Refer to the specification document on how to use the model in your
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// testbench.
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class aes_decrypt_model #(int Nk=4, int Nr=10);
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// Refer to section 5 fig.4 of FIPS-197 spec for definitions of Nk and Nr
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//
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// Key length Nk Nr
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// 128 4 10
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// 192 6 12
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// 256 8 14
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byte unsigned state[0:3][0:3];
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byte unsigned keysch[0:4*(Nr+1)-1][0:3];
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protected int unsigned curr_round;
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bit done; // done=1 -> decryption done, valid plaintext available for read.
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bit loaded; // Ciphertext loaded, ready to start decryption.
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function new(); // Constructor
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done = 0;
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loaded = 0;
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endfunction
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function int unsigned GetCurrRound;
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// Returns which round we are at in the decryption process. For AES decryption
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// round counts down from Nr to 0.
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GetCurrRound = curr_round;
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endfunction
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task LoadCt(bit [0:127] ct);
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// Populate state array with ciphertext and set loaded flag
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for (int j=0; j<=3; j++)
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for (int k=0; k<=3; k++) state[k][j] = ct[(32*j+8*k)+:8];
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loaded = 1;
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done = 0;
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curr_round = Nr; // Inverse cipher round counts down from Nr
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endtask
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function bit [0:127] GetState;
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// Returns current state as a 128-bit vector.
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// Once all rounds are completed, state contains the decrypted plaintext.
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for (int j=0; j<=3; j++)
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for (int k=0; k<=3; k++) GetState[(32*j+8*k)+:8] = state[k][j];
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endfunction
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function bit [0:127] GetCurrKsch;
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// Get key schedule of the current round.
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// Note that for decryption, round counts down from Nr.
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for (int j=0; j<=3; j++)
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for (int k=0; k<=3; k++) GetCurrKsch[(32*j+8*k)+:8] = keysch[curr_round*4+j][k];
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endfunction
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function bit [0:127] LookupKsch(int unsigned r);
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// Lookup key schedule for any round.
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for (int j=0; j<=3; j++)
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for (int k=0; k<=3; k++) LookupKsch[(32*j+8*k)+:8] = keysch[r*4+j][k];
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endfunction
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task KeyExpand(bit [0:4*8*Nk-1] key);
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// Load key to model and compute key_schedule
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int j=0;
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byte unsigned temp[0:3];
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byte unsigned Rcon[1:11] = {8'h01,8'h02,8'h04,8'h08,8'h10,8'h20,8'h40,8'h80,8'h1b,8'h36,8'h6c};
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byte unsigned kt[0:4*Nk-1]; // Array holding the key
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// Populate kt array
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for (int i=0; i<=4*Nk-1; i++) kt[i] = key[i*8+:8];
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while (j < Nk)
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begin
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keysch[j][0] = kt[4*j];
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keysch[j][1] = kt[4*j+1];
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keysch[j][2] = kt[4*j+2];
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keysch[j][3] = kt[4*j+3];
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j++;
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end
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// Now j = Nk
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while (j < 4*(Nr+1))
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begin
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temp[0] = keysch[j-1][0];
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temp[1] = keysch[j-1][1];
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temp[2] = keysch[j-1][2];
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temp[3] = keysch[j-1][3];
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if ((j % Nk) == 0) // When j is a multiple of key length
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begin
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RotWord(temp);
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SubWord(temp);
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temp[0] ^= Rcon[j/Nk];
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end
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else if ((Nk > 6) && ((j % Nk) == 4)) // Only Nk=8 (AES256) will hit this case
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SubWord(temp);
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keysch[j][0] = keysch[j-Nk][0] ^ temp[0];
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keysch[j][1] = keysch[j-Nk][1] ^ temp[1];
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keysch[j][2] = keysch[j-Nk][2] ^ temp[2];
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keysch[j][3] = keysch[j-Nk][3] ^ temp[3];
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j++;
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end
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endtask
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protected task RotWord(inout byte unsigned x[0:3]);
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byte unsigned tmp;
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tmp = x[0];
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x[0] = x[1];
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x[1] = x[2];
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x[2] = x[3];
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x[3] = tmp;
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endtask
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protected function byte unsigned inv_sbox_transform(byte unsigned x);
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// Inverse Sbox transform matrix
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const byte unsigned inv_sbox[0:255] = {
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// 0 1 2 3 4 5 6 7 8 9 a b c d e f
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// ===============================================================================================
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/*0*/ 8'h52,8'h09,8'h6a,8'hd5,8'h30,8'h36,8'ha5,8'h38,8'hbf,8'h40,8'ha3,8'h9e,8'h81,8'hf3,8'hd7,8'hfb,
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/*1*/ 8'h7c,8'he3,8'h39,8'h82,8'h9b,8'h2f,8'hff,8'h87,8'h34,8'h8e,8'h43,8'h44,8'hc4,8'hde,8'he9,8'hcb,
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/*2*/ 8'h54,8'h7b,8'h94,8'h32,8'ha6,8'hc2,8'h23,8'h3d,8'hee,8'h4c,8'h95,8'h0b,8'h42,8'hfa,8'hc3,8'h4e,
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/*3*/ 8'h08,8'h2e,8'ha1,8'h66,8'h28,8'hd9,8'h24,8'hb2,8'h76,8'h5b,8'ha2,8'h49,8'h6d,8'h8b,8'hd1,8'h25,
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/*4*/ 8'h72,8'hf8,8'hf6,8'h64,8'h86,8'h68,8'h98,8'h16,8'hd4,8'ha4,8'h5c,8'hcc,8'h5d,8'h65,8'hb6,8'h92,
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/*5*/ 8'h6c,8'h70,8'h48,8'h50,8'hfd,8'hed,8'hb9,8'hda,8'h5e,8'h15,8'h46,8'h57,8'ha7,8'h8d,8'h9d,8'h84,
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/*6*/ 8'h90,8'hd8,8'hab,8'h00,8'h8c,8'hbc,8'hd3,8'h0a,8'hf7,8'he4,8'h58,8'h05,8'hb8,8'hb3,8'h45,8'h06,
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/*7*/ 8'hd0,8'h2c,8'h1e,8'h8f,8'hca,8'h3f,8'h0f,8'h02,8'hc1,8'haf,8'hbd,8'h03,8'h01,8'h13,8'h8a,8'h6b,
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/*8*/ 8'h3a,8'h91,8'h11,8'h41,8'h4f,8'h67,8'hdc,8'hea,8'h97,8'hf2,8'hcf,8'hce,8'hf0,8'hb4,8'he6,8'h73,
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/*9*/ 8'h96,8'hac,8'h74,8'h22,8'he7,8'had,8'h35,8'h85,8'he2,8'hf9,8'h37,8'he8,8'h1c,8'h75,8'hdf,8'h6e,
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/*a*/ 8'h47,8'hf1,8'h1a,8'h71,8'h1d,8'h29,8'hc5,8'h89,8'h6f,8'hb7,8'h62,8'h0e,8'haa,8'h18,8'hbe,8'h1b,
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/*b*/ 8'hfc,8'h56,8'h3e,8'h4b,8'hc6,8'hd2,8'h79,8'h20,8'h9a,8'hdb,8'hc0,8'hfe,8'h78,8'hcd,8'h5a,8'hf4,
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/*c*/ 8'h1f,8'hdd,8'ha8,8'h33,8'h88,8'h07,8'hc7,8'h31,8'hb1,8'h12,8'h10,8'h59,8'h27,8'h80,8'hec,8'h5f,
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/*d*/ 8'h60,8'h51,8'h7f,8'ha9,8'h19,8'hb5,8'h4a,8'h0d,8'h2d,8'he5,8'h7a,8'h9f,8'h93,8'hc9,8'h9c,8'hef,
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/*e*/ 8'ha0,8'he0,8'h3b,8'h4d,8'hae,8'h2a,8'hf5,8'hb0,8'hc8,8'heb,8'hbb,8'h3c,8'h83,8'h53,8'h99,8'h61,
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/*f*/ 8'h17,8'h2b,8'h04,8'h7e,8'hba,8'h77,8'hd6,8'h26,8'he1,8'h69,8'h14,8'h63,8'h55,8'h21,8'h0c,8'h7d
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};
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inv_sbox_transform = inv_sbox[x];
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endfunction
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protected function byte unsigned sbox_transform(byte unsigned x);
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// Sbox transform matrix
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const byte unsigned sbox[0:255] = {
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// 0 1 2 3 4 5 6 7 8 9 a b c d e f
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// ===============================================================================================
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/*0*/ 8'h63,8'h7c,8'h77,8'h7b,8'hf2,8'h6b,8'h6f,8'hc5,8'h30,8'h01,8'h67,8'h2b,8'hfe,8'hd7,8'hab,8'h76,
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/*1*/ 8'hca,8'h82,8'hc9,8'h7d,8'hfa,8'h59,8'h47,8'hf0,8'had,8'hd4,8'ha2,8'haf,8'h9c,8'ha4,8'h72,8'hc0,
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/*2*/ 8'hb7,8'hfd,8'h93,8'h26,8'h36,8'h3f,8'hf7,8'hcc,8'h34,8'ha5,8'he5,8'hf1,8'h71,8'hd8,8'h31,8'h15,
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/*3*/ 8'h04,8'hc7,8'h23,8'hc3,8'h18,8'h96,8'h05,8'h9a,8'h07,8'h12,8'h80,8'he2,8'heb,8'h27,8'hb2,8'h75,
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/*4*/ 8'h09,8'h83,8'h2c,8'h1a,8'h1b,8'h6e,8'h5a,8'ha0,8'h52,8'h3b,8'hd6,8'hb3,8'h29,8'he3,8'h2f,8'h84,
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/*5*/ 8'h53,8'hd1,8'h00,8'hed,8'h20,8'hfc,8'hb1,8'h5b,8'h6a,8'hcb,8'hbe,8'h39,8'h4a,8'h4c,8'h58,8'hcf,
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/*6*/ 8'hd0,8'hef,8'haa,8'hfb,8'h43,8'h4d,8'h33,8'h85,8'h45,8'hf9,8'h02,8'h7f,8'h50,8'h3c,8'h9f,8'ha8,
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/*7*/ 8'h51,8'ha3,8'h40,8'h8f,8'h92,8'h9d,8'h38,8'hf5,8'hbc,8'hb6,8'hda,8'h21,8'h10,8'hff,8'hf3,8'hd2,
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/*8*/ 8'hcd,8'h0c,8'h13,8'hec,8'h5f,8'h97,8'h44,8'h17,8'hc4,8'ha7,8'h7e,8'h3d,8'h64,8'h5d,8'h19,8'h73,
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/*9*/ 8'h60,8'h81,8'h4f,8'hdc,8'h22,8'h2a,8'h90,8'h88,8'h46,8'hee,8'hb8,8'h14,8'hde,8'h5e,8'h0b,8'hdb,
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/*a*/ 8'he0,8'h32,8'h3a,8'h0a,8'h49,8'h06,8'h24,8'h5c,8'hc2,8'hd3,8'hac,8'h62,8'h91,8'h95,8'he4,8'h79,
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/*b*/ 8'he7,8'hc8,8'h37,8'h6d,8'h8d,8'hd5,8'h4e,8'ha9,8'h6c,8'h56,8'hf4,8'hea,8'h65,8'h7a,8'hae,8'h08,
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/*c*/ 8'hba,8'h78,8'h25,8'h2e,8'h1c,8'ha6,8'hb4,8'hc6,8'he8,8'hdd,8'h74,8'h1f,8'h4b,8'hbd,8'h8b,8'h8a,
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/*d*/ 8'h70,8'h3e,8'hb5,8'h66,8'h48,8'h03,8'hf6,8'h0e,8'h61,8'h35,8'h57,8'hb9,8'h86,8'hc1,8'h1d,8'h9e,
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/*e*/ 8'he1,8'hf8,8'h98,8'h11,8'h69,8'hd9,8'h8e,8'h94,8'h9b,8'h1e,8'h87,8'he9,8'hce,8'h55,8'h28,8'hdf,
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/*f*/ 8'h8c,8'ha1,8'h89,8'h0d,8'hbf,8'he6,8'h42,8'h68,8'h41,8'h99,8'h2d,8'h0f,8'hb0,8'h54,8'hbb,8'h16
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};
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sbox_transform = sbox[x];
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endfunction
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protected task SubBytes;
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for (int j=0; j<=3; j++)
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for (int k=0; k<=3; k++) state[j][k] = sbox_transform(state[j][k]);
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endtask
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protected task InvSubBytes;
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for (int j=0; j<=3; j++)
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for (int k=0; k<=3; k++) state[j][k] = inv_sbox_transform(state[j][k]);
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endtask
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|
| 227 |
|
|
protected task SubWord(inout byte unsigned x[0:3]);
|
| 228 |
|
|
x[0] = sbox_transform(x[0]);
|
| 229 |
|
|
x[1] = sbox_transform(x[1]);
|
| 230 |
|
|
x[2] = sbox_transform(x[2]);
|
| 231 |
|
|
x[3] = sbox_transform(x[3]);
|
| 232 |
|
|
endtask
|
| 233 |
|
|
|
| 234 |
|
|
protected task InvShiftRows;
|
| 235 |
|
|
byte unsigned tmp_state[1:3][0:3]; // Row 0 of state is not shifted
|
| 236 |
|
|
|
| 237 |
|
|
for (int j=1; j<=3; j++)
|
| 238 |
|
|
for (int k=0; k<=3; k++) tmp_state[j][k] = state[j][(k+4-j)%4];
|
| 239 |
|
|
|
| 240 |
|
|
for (int j=1; j<=3; j++)
|
| 241 |
|
|
for (int k=0; k<=3; k++) state[j][k] = tmp_state[j][k];
|
| 242 |
|
|
endtask
|
| 243 |
|
|
|
| 244 |
|
|
protected function byte unsigned xtime(byte unsigned x);
|
| 245 |
|
|
// Multiplication by 2 over GF(256)
|
| 246 |
|
|
// Refer to FIPS-197 spec section 4.2.1 on definition of GF(256) multiplication
|
| 247 |
|
|
xtime = (x[7])? (x<<1) ^ 8'h1b : x<<1;
|
| 248 |
|
|
endfunction
|
| 249 |
|
|
|
| 250 |
|
|
protected function byte unsigned GFmul4(byte unsigned x);
|
| 251 |
|
|
// Multiply by 4 over GF(256)
|
| 252 |
|
|
// 4*x = 2*(2*x)
|
| 253 |
|
|
GFmul4 = xtime(xtime(x));
|
| 254 |
|
|
endfunction
|
| 255 |
|
|
|
| 256 |
|
|
protected function byte unsigned GFmul8(byte unsigned x);
|
| 257 |
|
|
// Multiply by 8 over GF(256)
|
| 258 |
|
|
// 8*x = 2*(4*x)
|
| 259 |
|
|
GFmul8 = xtime(GFmul4(x));
|
| 260 |
|
|
endfunction
|
| 261 |
|
|
|
| 262 |
|
|
protected function byte unsigned GFmul9(byte unsigned x);
|
| 263 |
|
|
// Multiply by 9 over GF(256)
|
| 264 |
|
|
// 9*x = 8*x + x
|
| 265 |
|
|
// Addition over GF(256) is xor
|
| 266 |
|
|
GFmul9 = GFmul8(x) ^ x;
|
| 267 |
|
|
endfunction
|
| 268 |
|
|
|
| 269 |
|
|
protected function byte unsigned GFmulb(byte unsigned x);
|
| 270 |
|
|
// Multiply by 0xb over GF(256)
|
| 271 |
|
|
// b*x = 8*x + 2*x +x
|
| 272 |
|
|
GFmulb = GFmul8(x) ^ xtime(x) ^ x;
|
| 273 |
|
|
endfunction
|
| 274 |
|
|
|
| 275 |
|
|
protected function byte unsigned GFmuld(byte unsigned x);
|
| 276 |
|
|
// Multiply by 0xd over GF(256)
|
| 277 |
|
|
// d*x = 8*x + 4*x + x
|
| 278 |
|
|
GFmuld = GFmul8(x) ^ GFmul4(x) ^ x;
|
| 279 |
|
|
endfunction
|
| 280 |
|
|
|
| 281 |
|
|
protected function byte unsigned GFmule(byte unsigned x);
|
| 282 |
|
|
// Multiply by 0xe over GF(256)
|
| 283 |
|
|
// e*x = 8*x + 4*x +2*x
|
| 284 |
|
|
GFmule = GFmul8(x) ^ GFmul4(x) ^ xtime(x);
|
| 285 |
|
|
endfunction
|
| 286 |
|
|
|
| 287 |
|
|
protected task InvMixColumns;
|
| 288 |
|
|
byte unsigned tmp_col[0:3];
|
| 289 |
|
|
|
| 290 |
|
|
for (int j=0; j<=3; j++)
|
| 291 |
|
|
begin
|
| 292 |
|
|
tmp_col[0] = GFmule(state[0][j]) ^ GFmulb(state[1][j]) ^ GFmuld(state[2][j]) ^ GFmul9(state[3][j]);
|
| 293 |
|
|
tmp_col[1] = GFmul9(state[0][j]) ^ GFmule(state[1][j]) ^ GFmulb(state[2][j]) ^ GFmuld(state[3][j]);
|
| 294 |
|
|
tmp_col[2] = GFmuld(state[0][j]) ^ GFmul9(state[1][j]) ^ GFmule(state[2][j]) ^ GFmulb(state[3][j]);
|
| 295 |
|
|
tmp_col[3] = GFmulb(state[0][j]) ^ GFmuld(state[1][j]) ^ GFmul9(state[2][j]) ^ GFmule(state[3][j]);
|
| 296 |
|
|
|
| 297 |
|
|
state[0][j] = tmp_col[0];
|
| 298 |
|
|
state[1][j] = tmp_col[1];
|
| 299 |
|
|
state[2][j] = tmp_col[2];
|
| 300 |
|
|
state[3][j] = tmp_col[3];
|
| 301 |
|
|
end
|
| 302 |
|
|
endtask
|
| 303 |
|
|
|
| 304 |
|
|
protected task AddRoundKey;
|
| 305 |
|
|
for (int j=0; j<=3; j++)
|
| 306 |
|
|
for (int k=0; k<=3; k++) state[k][j] ^= keysch[curr_round*4+j][k];
|
| 307 |
|
|
endtask
|
| 308 |
|
|
|
| 309 |
|
|
task run(int mode);
|
| 310 |
|
|
// Run inverse cipher rounds as defined in section 5.3 of FIPS-197 spec.
|
| 311 |
|
|
// mode=0 -> Run from current round to completion
|
| 312 |
|
|
// mode=1 -> Run 1 round only
|
| 313 |
|
|
// Both LoadCt() and KeyExpand() must be called first before calling run()
|
| 314 |
|
|
// to ensure the inverse cipher doesn't work on garbage.
|
| 315 |
|
|
|
| 316 |
|
|
// Only continue if ciphertext is loaded and there are unfinished round(s)
|
| 317 |
|
|
if (loaded & ~done)
|
| 318 |
|
|
do
|
| 319 |
|
|
begin
|
| 320 |
|
|
unique if (curr_round == Nr)
|
| 321 |
|
|
begin
|
| 322 |
|
|
`ifdef INTERNAL_DEBUG
|
| 323 |
|
|
$display("round[%2d].istart\t%h",Nr-curr_round,GetState);
|
| 324 |
|
|
$display("round[%2d].ik_sch\t%h",Nr-curr_round,GetCurrKsch);
|
| 325 |
|
|
`endif
|
| 326 |
|
|
|
| 327 |
|
|
done = 0;
|
| 328 |
|
|
AddRoundKey;
|
| 329 |
|
|
curr_round--;
|
| 330 |
|
|
end
|
| 331 |
|
|
else if ((curr_round <= Nr-1) && (curr_round >= 1))
|
| 332 |
|
|
begin
|
| 333 |
|
|
`ifdef INTERNAL_DEBUG
|
| 334 |
|
|
$display("round[%2d].istart\t%h",Nr-curr_round,GetState);
|
| 335 |
|
|
`endif
|
| 336 |
|
|
|
| 337 |
|
|
InvShiftRows;
|
| 338 |
|
|
`ifdef INTERNAL_DEBUG
|
| 339 |
|
|
$display("round[%2d].is_row\t%h",Nr-curr_round,GetState);
|
| 340 |
|
|
`endif
|
| 341 |
|
|
|
| 342 |
|
|
InvSubBytes;
|
| 343 |
|
|
`ifdef INTERNAL_DEBUG
|
| 344 |
|
|
$display("round[%2d].is_box\t%h",Nr-curr_round,GetState);
|
| 345 |
|
|
$display("round[%2d].ik_sch\t%h",Nr-curr_round,GetCurrKsch);
|
| 346 |
|
|
`endif
|
| 347 |
|
|
|
| 348 |
|
|
AddRoundKey;
|
| 349 |
|
|
`ifdef INTERNAL_DEBUG
|
| 350 |
|
|
$display("round[%2d].ik_add\t%h",Nr-curr_round,GetState);
|
| 351 |
|
|
`endif
|
| 352 |
|
|
|
| 353 |
|
|
InvMixColumns;
|
| 354 |
|
|
curr_round--;
|
| 355 |
|
|
end
|
| 356 |
|
|
else if (curr_round == 0)
|
| 357 |
|
|
begin
|
| 358 |
|
|
`ifdef INTERNAL_DEBUG
|
| 359 |
|
|
$display("round[%2d].istart\t%h",Nr-curr_round,GetState);
|
| 360 |
|
|
`endif
|
| 361 |
|
|
|
| 362 |
|
|
InvShiftRows;
|
| 363 |
|
|
`ifdef INTERNAL_DEBUG
|
| 364 |
|
|
$display("round[%2d].is_row\t%h",Nr-curr_round,GetState);
|
| 365 |
|
|
`endif
|
| 366 |
|
|
|
| 367 |
|
|
InvSubBytes;
|
| 368 |
|
|
`ifdef INTERNAL_DEBUG
|
| 369 |
|
|
$display("round[%2d].is_box\t%h",Nr-curr_round,GetState);
|
| 370 |
|
|
$display("round[%2d].ik_sch\t%h",Nr-curr_round,GetCurrKsch);
|
| 371 |
|
|
`endif
|
| 372 |
|
|
|
| 373 |
|
|
AddRoundKey;
|
| 374 |
|
|
`ifdef INTERNAL_DEBUG
|
| 375 |
|
|
$display("round[%2d].ioutput\t%h",Nr-curr_round,GetState);
|
| 376 |
|
|
`endif
|
| 377 |
|
|
|
| 378 |
|
|
done = 1; // Last round completed
|
| 379 |
|
|
loaded = 0;
|
| 380 |
|
|
end
|
| 381 |
|
|
|
| 382 |
|
|
if (mode == 1) break;
|
| 383 |
|
|
end
|
| 384 |
|
|
while (done == 0);
|
| 385 |
|
|
|
| 386 |
|
|
// Either ciphertext is not loaded or decryption has already completed
|
| 387 |
|
|
else $display("#Info : aes_decrypt_model::run() has nothing to do");
|
| 388 |
|
|
endtask
|
| 389 |
|
|
endclass // aes_decrypt_model
|
| 390 |
|
|
|
| 391 |
|
|
// The following types should be used for declaration of aes class objects in your source code.
|
| 392 |
|
|
// e.g. ....
|
| 393 |
|
|
// aes256_decrypt_t my_aes_decryptor;
|
| 394 |
|
|
// bit [0:127] pt;
|
| 395 |
|
|
// ....
|
| 396 |
|
|
// my_aes_decryptor = new;
|
| 397 |
|
|
// my_aes_decryptor.KeyExpand(256'h.......);
|
| 398 |
|
|
// my_aes_decryptor.LoadCt(128'h.........);
|
| 399 |
|
|
// my_aes_descryptor.run(0);
|
| 400 |
|
|
// pt = my_aes_descryptor.GetState();
|
| 401 |
|
|
|
| 402 |
|
|
typedef aes_decrypt_model #(.Nk(8),.Nr(14)) aes256_decrypt_t;
|
| 403 |
|
|
typedef aes_decrypt_model #(.Nk(6),.Nr(12)) aes192_decrypt_t;
|
| 404 |
|
|
typedef aes_decrypt_model #(.Nk(4),.Nr(10)) aes128_decrypt_t;
|
