Subversion Repositories aes-encryption

/////////////////////////////////////////////////////////////////////

////                                                             ////

////  AES Cipher Top Level                                       ////

////                                                             ////

////                                                             ////

////  Author: Rudolf Usselmann                                   ////

////          rudi@asics.ws                                      ////

////                                                             ////

////                                                             ////

////  Downloaded from: http://www.opencores.org/cores/aes_core/  ////

////                                                             ////

/////////////////////////////////////////////////////////////////////

////                                                             ////

//// Copyright (C) 2000-2002 Rudolf Usselmann                    ////

////                         www.asics.ws                        ////

////                         rudi@asics.ws                       ////

////                                                             ////

//// This source file may be used and distributed without        ////

//// restriction provided that this copyright statement is not   ////

//// removed from the file and that any derivative work contains ////

//// the original copyright notice and the associated disclaimer.////

////                                                             ////

////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////

//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////

//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////

//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////

//// 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.                                 ////

////                                                             ////

/////////////////////////////////////////////////////////////////////

//// Modified to achieve 5 cycles - stage  functionality             ////

//// By Tariq Bashir Ahmad                                                                       ////   

////  tariq.bashir@gmail.com                                                             ////

////  http://www.ecs.umass.edu/~tbashir                                          ////

`timescale 1 ns/1 ps

module aes_cipher_top(clk, rst, ld, done, key, text_in, text_out,aes_en);

input           clk, rst;

input           ld;

output          done;

input   [127:0]  key;

input   [127:0]  text_in;

output  [127:0]  text_out;

input aes_en;

////////////////////////////////////////////////////////////////////

//

// Local Wires

//

wire    [31:0]   w0, w1, w2, w3, w4, w5, w6, w7;

/*wire  [127:0] key_odd,key_even;

*/

reg     [127:0]  text_in_r;

reg     [127:0]  text_out;

reg     [127:0]  text_out_temp;

reg     [7:0]    sa00, sa01, sa02, sa03;

reg     [7:0]    sa10, sa11, sa12, sa13;

reg     [7:0]    sa20, sa21, sa22, sa23;

reg     [7:0]    sa30, sa31, sa32, sa33;

wire    [7:0]    sa00_next, sa01_next, sa02_next, sa03_next;

wire    [7:0]    sa10_next, sa11_next, sa12_next, sa13_next;

wire    [7:0]    sa20_next, sa21_next, sa22_next, sa23_next;

wire    [7:0]    sa30_next, sa31_next, sa32_next, sa33_next;

wire    [7:0]    sa00_sub, sa01_sub, sa02_sub, sa03_sub;

wire    [7:0]    sa10_sub, sa11_sub, sa12_sub, sa13_sub;

wire  [7:0]      sa20_sub, sa21_sub, sa22_sub, sa23_sub;

wire    [7:0]    sa30_sub, sa31_sub, sa32_sub, sa33_sub;

wire    [7:0]    sa00_sr, sa01_sr, sa02_sr, sa03_sr;

wire    [7:0]    sa10_sr, sa11_sr, sa12_sr, sa13_sr;

wire    [7:0]    sa20_sr, sa21_sr, sa22_sr, sa23_sr;

wire    [7:0]    sa30_sr, sa31_sr, sa32_sr, sa33_sr;

wire    [7:0]    sa00_mc, sa01_mc, sa02_mc, sa03_mc;

wire    [7:0]    sa10_mc, sa11_mc, sa12_mc, sa13_mc;

wire    [7:0]    sa20_mc, sa21_mc, sa22_mc, sa23_mc;

wire    [7:0]    sa30_mc, sa31_mc, sa32_mc, sa33_mc;

wire    [7:0]    sa00_next_round2, sa01_next_round2, sa02_next_round2, sa03_next_round2;

wire    [7:0]    sa10_next_round2, sa11_next_round2, sa12_next_round2, sa13_next_round2;

wire    [7:0]    sa20_next_round2, sa21_next_round2, sa22_next_round2, sa23_next_round2;

wire    [7:0]    sa30_next_round2, sa31_next_round2, sa32_next_round2, sa33_next_round2;

wire    [7:0]    sa00_sub_round2, sa01_sub_round2, sa02_sub_round2, sa03_sub_round2;

wire    [7:0]    sa10_sub_round2, sa11_sub_round2, sa12_sub_round2, sa13_sub_round2;

wire  [7:0]      sa20_sub_round2, sa21_sub_round2, sa22_sub_round2, sa23_sub_round2;

wire    [7:0]    sa30_sub_round2, sa31_sub_round2, sa32_sub_round2, sa33_sub_round2;

wire    [7:0]    sa00_sr_round2, sa01_sr_round2, sa02_sr_round2, sa03_sr_round2;

wire    [7:0]    sa10_sr_round2, sa11_sr_round2, sa12_sr_round2, sa13_sr_round2;

wire    [7:0]    sa20_sr_round2, sa21_sr_round2, sa22_sr_round2, sa23_sr_round2;

wire    [7:0]    sa30_sr_round2, sa31_sr_round2, sa32_sr_round2, sa33_sr_round2;

wire    [7:0]    sa00_mc_round2, sa01_mc_round2, sa02_mc_round2, sa03_mc_round2;

wire    [7:0]    sa10_mc_round2, sa11_mc_round2, sa12_mc_round2, sa13_mc_round2;

wire    [7:0]    sa20_mc_round2, sa21_mc_round2, sa22_mc_round2, sa23_mc_round2;

wire    [7:0]    sa30_mc_round2, sa31_mc_round2, sa32_mc_round2, sa33_mc_round2;

reg             done, ld_r;

reg     [3:0]    dcnt;

reg             done2;

////////////////////////////////////////////////////////////////////

//

// Misc Logic

//

always @(posedge clk)

if(aes_en)

begin

        if(rst) begin dcnt <=  4'h0;     end

        else

        if(ld)  begin   dcnt <=  4'h6;   end

        else

        if(|dcnt) begin dcnt <=  dcnt - 4'h1;  end

end

always @(posedge clk) done <=  !(|dcnt[3:1]) & dcnt[0] & !ld;

always @(posedge clk) if(ld) text_in_r <=  text_in;

always @(posedge clk) ld_r <=  ld;

////////////////////////////////////////////////////////////////////

// key expansion

aes_key_expand_128 u0(

        .clk(           clk     ),

        .kld(           ld_r    ),

        .key(           key     ),

        .w0(            w0      ),

        .w1(            w1      ),

        .w2(            w2      ),

        .w3(            w3      ),

        .w4_reg(                w4      ),

        .w5_reg(                w5      ),

        .w6_reg(                w6      ),

        .w7_reg(                w7      )

                                                        );

/*assign key_odd  = {w0,w1,w2,w3};

assign key_even = {w4,w5,w6,w7};

*/

/*assign {w0,w1,w2,w3} = 128'h0;

assign {w4,w5,w6,w7} = 128'h62636363626363636263636362636363;

*/

// Initial Permutation (AddRoundKey)

//

/*

always @(posedge clk)

begin

  w0 <= w0_net;

  w1 <= w1_net;

  w2 <= w2_net;

  w3 <= w3_net;

  w4 <= w4_net;

  w5 <= w5_net;

  w6 <= w6_net;

  w7 <= w7_net;

end

*/

always @(posedge clk)

begin

        sa33 <=  ld_r ? text_in_r[007:000] ^ w3[07:00] : sa33_mc_round2 ^ w3[07:00];

        sa23 <=  ld_r ? text_in_r[015:008] ^ w3[15:08] : sa23_mc_round2 ^ w3[15:08];

        sa13 <=  ld_r ? text_in_r[023:016] ^ w3[23:16] : sa13_mc_round2 ^ w3[23:16];

        sa03 <=  ld_r ? text_in_r[031:024] ^ w3[31:24] : sa03_mc_round2 ^ w3[31:24];

        sa32 <=  ld_r ? text_in_r[039:032] ^ w2[07:00] : sa32_mc_round2 ^ w2[07:00];

        sa22 <=  ld_r ? text_in_r[047:040] ^ w2[15:08] : sa22_mc_round2 ^ w2[15:08];

        sa12 <=  ld_r ? text_in_r[055:048] ^ w2[23:16] : sa12_mc_round2 ^ w2[23:16];

        sa02 <=  ld_r ? text_in_r[063:056] ^ w2[31:24] : sa02_mc_round2 ^ w2[31:24];

        sa31 <=  ld_r ? text_in_r[071:064] ^ w1[07:00] : sa31_mc_round2 ^ w1[07:00];

        sa21 <=  ld_r ? text_in_r[079:072] ^ w1[15:08] : sa21_mc_round2 ^ w1[15:08];

        sa11 <=  ld_r ? text_in_r[087:080] ^ w1[23:16] : sa11_mc_round2 ^ w1[23:16];

        sa01 <=  ld_r ? text_in_r[095:088] ^ w1[31:24] : sa01_mc_round2 ^ w1[31:24];

        sa30 <=  ld_r ? text_in_r[103:096] ^ w0[07:00] : sa30_mc_round2 ^ w0[07:00];

        sa20 <=  ld_r ? text_in_r[111:104] ^ w0[15:08] : sa20_mc_round2 ^ w0[15:08];

        sa10 <=  ld_r ? text_in_r[119:112] ^ w0[23:16] : sa10_mc_round2 ^ w0[23:16];

        sa00 <=  ld_r ? text_in_r[127:120] ^ w0[31:24] : sa00_mc_round2 ^ w0[31:24];

                /*$strobe($time,": roundkeyodd = %h\n",{w0,w1,w2,w3});

                $strobe($time,": state is %h\n",{sa00, sa01, sa02, sa03,

                                                                                                         sa10, sa11, sa12, sa13,

                                                                                                         sa20, sa21, sa22, sa23,

                                                                                                         sa30, sa31, sa32, sa33});*/

end

////////////////////////////////////////////////////////////////////

//

// Modules instantiation

//

//sbox lookup

aes_sbox us00(  .a(     sa00    ), .d(  sa00_sub        ));

aes_sbox us01(  .a(     sa01    ), .d(  sa01_sub        ));

aes_sbox us02(  .a(     sa02    ), .d(  sa02_sub        ));

aes_sbox us03(  .a(     sa03    ), .d(  sa03_sub        ));

aes_sbox us10(  .a(     sa10    ), .d(  sa10_sub        ));

aes_sbox us11(  .a(     sa11    ), .d(  sa11_sub        ));

aes_sbox us12(  .a(     sa12    ), .d(  sa12_sub        ));

aes_sbox us13(  .a(     sa13    ), .d(  sa13_sub        ));

aes_sbox us20(  .a(     sa20    ), .d(  sa20_sub        ));

aes_sbox us21(  .a(     sa21    ), .d(  sa21_sub        ));

aes_sbox us22(  .a(     sa22    ), .d(  sa22_sub        ));

aes_sbox us23(  .a(     sa23    ), .d(  sa23_sub        ));

aes_sbox us30(  .a(     sa30    ), .d(  sa30_sub        ));

aes_sbox us31(  .a(     sa31    ), .d(  sa31_sub        ));

aes_sbox us32(  .a(     sa32    ), .d(  sa32_sub        ));

aes_sbox us33(  .a(     sa33    ), .d(  sa33_sub        ));

////////////////////////////////////////////////////////////////////

//

// Round Permutations

//

assign sa00_sr = sa00_sub;              //

assign sa01_sr = sa01_sub;              //no shift

assign sa02_sr = sa02_sub;              //

assign sa03_sr = sa03_sub;              //

assign sa10_sr = sa11_sub;              //

assign sa11_sr = sa12_sub;              // left shift by 1

assign sa12_sr = sa13_sub;              //

assign sa13_sr = sa10_sub;              //

assign sa20_sr = sa22_sub;              //

assign sa21_sr = sa23_sub;              //      left shift by 2

assign sa22_sr = sa20_sub;              //

assign sa23_sr = sa21_sub;              //

assign sa30_sr = sa33_sub;              //

assign sa31_sr = sa30_sub;              // left shift by 3

assign sa32_sr = sa31_sub;              //

assign sa33_sr = sa32_sub;              //

// mix column operation

assign {sa00_mc, sa10_mc, sa20_mc, sa30_mc}  = mix_col(sa00_sr,sa10_sr,sa20_sr,sa30_sr);

assign {sa01_mc, sa11_mc, sa21_mc, sa31_mc}  = mix_col(sa01_sr,sa11_sr,sa21_sr,sa31_sr);

assign {sa02_mc, sa12_mc, sa22_mc, sa32_mc}  = mix_col(sa02_sr,sa12_sr,sa22_sr,sa32_sr);

assign {sa03_mc, sa13_mc, sa23_mc, sa33_mc}  = mix_col(sa03_sr,sa13_sr,sa23_sr,sa33_sr);

//// add round key

assign sa00_next_round2 = sa00_mc ^ w4[31:24];

assign sa01_next_round2 = sa01_mc ^ w5[31:24];

assign sa02_next_round2 = sa02_mc ^ w6[31:24];

assign sa03_next_round2 = sa03_mc ^ w7[31:24];

assign sa10_next_round2 = sa10_mc ^ w4[23:16];

assign sa11_next_round2 = sa11_mc ^ w5[23:16];

assign sa12_next_round2 = sa12_mc ^ w6[23:16];

assign sa13_next_round2 = sa13_mc ^ w7[23:16];

assign sa20_next_round2 = sa20_mc ^ w4[15:08];

assign sa21_next_round2 = sa21_mc ^ w5[15:08];

assign sa22_next_round2 = sa22_mc ^ w6[15:08];

assign sa23_next_round2 = sa23_mc ^ w7[15:08];

assign sa30_next_round2 = sa30_mc ^ w4[07:00];

assign sa31_next_round2 = sa31_mc ^ w5[07:00];

assign sa32_next_round2 = sa32_mc ^ w6[07:00];

assign sa33_next_round2 = sa33_mc ^ w7[07:00];

always @(posedge clk)

 if(aes_en && ~rst)

begin

         /* $strobe($time,": roundkeyodd = %h, text_out_odd is %h\n",{w0,w1,w2,w3},text_out_temp);

          $strobe($time,": roundkeyeven is %h\n",{w4,w5,w6,w7});        */

          text_out_temp[127:120] <=  sa00_sr ^ w4[31:24];

          text_out_temp[095:088] <=  sa01_sr ^ w5[31:24];

     text_out_temp[063:056] <=  sa02_sr ^ w6[31:24];

          text_out_temp[031:024] <=  sa03_sr ^ w7[31:24];

          text_out_temp[119:112] <=  sa10_sr ^ w4[23:16];

          text_out_temp[087:080] <=  sa11_sr ^ w5[23:16];

          text_out_temp[055:048] <=  sa12_sr ^ w6[23:16];

          text_out_temp[023:016] <=  sa13_sr ^ w7[23:16];

          text_out_temp[111:104] <=  sa20_sr ^ w4[15:08];

          text_out_temp[079:072] <=  sa21_sr ^ w5[15:08];

          text_out_temp[047:040] <=  sa22_sr ^ w6[15:08];

          text_out_temp[015:008] <=  sa23_sr ^ w7[15:08];

          text_out_temp[103:096] <=  sa30_sr ^ w4[07:00];

          text_out_temp[071:064] <=  sa31_sr ^ w5[07:00];

          text_out_temp[039:032] <=  sa32_sr ^ w6[07:00];

          text_out_temp[007:000] <=  sa33_sr ^ w7[07:00];

end

//////////////////////  round i + 1 //////////////////////////////////

//sbox lookup

aes_sbox us00_round2(   .a(     sa00_next_round2        ), .d(  sa00_sub_round2 ));

aes_sbox us01_round2(   .a(     sa01_next_round2        ), .d(  sa01_sub_round2 ));

aes_sbox us02_round2(   .a(     sa02_next_round2        ), .d(  sa02_sub_round2 ));

aes_sbox us03_round2(   .a(     sa03_next_round2        ), .d(  sa03_sub_round2 ));

aes_sbox us10_round2(   .a(     sa10_next_round2        ), .d(  sa10_sub_round2 ));

aes_sbox us11_round2(   .a(     sa11_next_round2        ), .d(  sa11_sub_round2 ));

aes_sbox us12_round2(   .a(     sa12_next_round2        ), .d(  sa12_sub_round2 ));

aes_sbox us13_round2(   .a(     sa13_next_round2        ), .d(  sa13_sub_round2 ));

aes_sbox us20_round2(   .a(     sa20_next_round2        ), .d(  sa20_sub_round2 ));

aes_sbox us21_round2(   .a(     sa21_next_round2        ), .d(  sa21_sub_round2 ));

aes_sbox us22_round2(   .a(     sa22_next_round2        ), .d(  sa22_sub_round2 ));

aes_sbox us23_round2(   .a(     sa23_next_round2        ), .d(  sa23_sub_round2 ));

aes_sbox us30_round2(   .a(     sa30_next_round2        ), .d(  sa30_sub_round2 ));

aes_sbox us31_round2(   .a(     sa31_next_round2        ), .d(  sa31_sub_round2 ));

aes_sbox us32_round2(   .a(     sa32_next_round2        ), .d(  sa32_sub_round2 ));

aes_sbox us33_round2(   .a(     sa33_next_round2        ), .d(  sa33_sub_round2 ));

// Round Permutations

//

assign sa00_sr_round2 = sa00_sub_round2;                //

assign sa01_sr_round2 = sa01_sub_round2;                //no shift

assign sa02_sr_round2 = sa02_sub_round2;                //

assign sa03_sr_round2 = sa03_sub_round2;                //

assign sa10_sr_round2 = sa11_sub_round2;                //

assign sa11_sr_round2 = sa12_sub_round2;                // left shift by 1

assign sa12_sr_round2 = sa13_sub_round2;                //

assign sa13_sr_round2 = sa10_sub_round2;                //

assign sa20_sr_round2 = sa22_sub_round2;                //

assign sa21_sr_round2 = sa23_sub_round2;                //      left shift by 2

assign sa22_sr_round2 = sa20_sub_round2;                //

assign sa23_sr_round2 = sa21_sub_round2;                //

assign sa30_sr_round2 = sa33_sub_round2;                //

assign sa31_sr_round2 = sa30_sub_round2;                // left shift by 3

assign sa32_sr_round2 = sa31_sub_round2;                //

assign sa33_sr_round2 = sa32_sub_round2;                //

// mix column operation

assign {sa00_mc_round2, sa10_mc_round2, sa20_mc_round2, sa30_mc_round2}  = mix_col(sa00_sr_round2,sa10_sr_round2,sa20_sr_round2,sa30_sr_round2);

assign {sa01_mc_round2, sa11_mc_round2, sa21_mc_round2, sa31_mc_round2}  = mix_col(sa01_sr_round2,sa11_sr_round2,sa21_sr_round2,sa31_sr_round2);

assign {sa02_mc_round2, sa12_mc_round2, sa22_mc_round2, sa32_mc_round2}  = mix_col(sa02_sr_round2,sa12_sr_round2,sa22_sr_round2,sa32_sr_round2);

assign {sa03_mc_round2, sa13_mc_round2, sa23_mc_round2, sa33_mc_round2}  = mix_col(sa03_sr_round2,sa13_sr_round2,sa23_sr_round2,sa33_sr_round2);

////////////////////////////////////////////////////////////////////

//

// Final text output

//

always @(posedge clk)

 if(aes_en && ~rst)

 begin

                /*  $strobe($time,": round_key2 is %h\n",{w4,w5,w6,w7});

                  $strobe($time,": roundkeyeven = %h, text_out_even is %h\n",{w4,w5,w6,w7},text_out);*/

                  text_out[127:120] <=  sa00_sr_round2 ^ w0[31:24];

                  text_out[095:088] <=  sa01_sr_round2 ^ w1[31:24];

                  text_out[063:056] <=  sa02_sr_round2 ^ w2[31:24];

                  text_out[031:024] <=  sa03_sr_round2 ^ w3[31:24];

                  text_out[119:112] <=  sa10_sr_round2 ^ w0[23:16];

                  text_out[087:080] <=  sa11_sr_round2 ^ w1[23:16];

                  text_out[055:048] <=  sa12_sr_round2 ^ w2[23:16];

                  text_out[023:016] <=  sa13_sr_round2 ^ w3[23:16];

                  text_out[111:104] <=  sa20_sr_round2 ^ w0[15:08];

                  text_out[079:072] <=  sa21_sr_round2 ^ w1[15:08];

                  text_out[047:040] <=  sa22_sr_round2 ^ w2[15:08];

                  text_out[015:008] <=  sa23_sr_round2 ^ w3[15:08];

                  text_out[103:096] <=  sa30_sr_round2 ^ w0[07:00];

                  text_out[071:064] <=  sa31_sr_round2 ^ w1[07:00];

                  text_out[039:032] <=  sa32_sr_round2 ^ w2[07:00];

                  text_out[007:000] <=  sa33_sr_round2 ^ w3[07:00];

        end

always @(posedge clk)

        begin

/*      $strobe($time,": text_out_temp is %h\n",text_out_temp);

*/      /*

        $strobe($time,": subbytes is %h\n",{sa00_sub, sa01_sub, sa02_sub, sa03_sub,

                                                                                                         sa10_sub, sa11_sub, sa12_sub, sa13_sub,

                                                                                                         sa20_sub, sa21_sub, sa22_sub, sa23_sub,

                                                                                                         sa30_sub, sa31_sub, sa32_sub, sa33_sub});

        $strobe($time,": shiftrows is %h\n",{sa00_sr, sa01_sr, sa02_sr, sa03_sr,

                                                                                                          sa10_sr, sa11_sr, sa12_sr, sa13_sr,

                                                                                                          sa20_sr, sa21_sr, sa22_sr, sa23_sr,

                                                                                                          sa30_sr, sa31_sr, sa32_sr, sa33_sr});

        $strobe($time,": mixcolumn is %h\n",{sa00_mc, sa01_mc, sa02_mc, sa03_mc,

                                                                                                          sa10_mc, sa11_mc, sa12_mc, sa13_mc,

                                                                                                          sa20_mc, sa21_mc, sa22_mc, sa23_mc,

                                                                                                          sa30_mc, sa31_mc, sa32_mc, sa33_mc});

        $strobe($time,": sa_next_into_even is %h\n",{sa00_next_round2, sa01_next_round2, sa02_next_round2, sa03_next_round2,

                                                                                                                                 sa10_next_round2, sa11_next_round2, sa12_next_round2, sa13_next_round2,

                                                                                                                                 sa20_next_round2, sa21_next_round2, sa22_next_round2, sa23_next_round2,

                                                                                                                                 sa30_next_round2, sa31_next_round2, sa32_next_round2, sa33_next_round2});

        $strobe($time,": subbytes_e is %h\n",{sa00_sub_round2, sa01_sub_round2, sa02_sub_round2, sa03_sub_round2,

                                                                                                         sa10_sub_round2, sa11_sub_round2, sa12_sub_round2, sa13_sub_round2,

                                                                                                         sa20_sub_round2, sa21_sub_round2, sa22_sub_round2, sa23_sub_round2,

                                                                                                         sa30_sub_round2, sa31_sub_round2, sa32_sub_round2, sa33_sub_round2});

        $strobe($time,": shiftrows_e is %h\n",{sa00_sr_round2, sa01_sr_round2, sa02_sr_round2, sa03_sr_round2,

                                                                                                          sa10_sr_round2, sa11_sr_round2, sa12_sr_round2, sa13_sr_round2,

                                                                                                          sa20_sr_round2, sa21_sr_round2, sa22_sr_round2, sa23_sr_round2,

                                                                                                          sa30_sr_round2, sa31_sr_round2, sa32_sr_round2, sa33_sr_round2});

        $strobe($time,": mixcolumn_e is %h\n",{sa00_mc_round2, sa01_mc_round2, sa02_mc_round2, sa03_mc_round2,

                                                                                                          sa10_mc_round2, sa11_mc_round2, sa12_mc_round2, sa13_mc_round2,

                                                                                                          sa20_mc_round2, sa21_mc_round2, sa22_mc_round2, sa23_mc_round2,

                                                                                                          sa30_mc_round2, sa31_mc_round2, sa32_mc_round2, sa33_mc_round2});

        */

        end

/*

always @(posedge clk)

       begin

                                if(done)

                                                begin

                                                        text_out_64 <= text_out[127:64];

//                                                      done2 <= 1;

                                                end

                                else if(~done)

                                                        text_out_64 <= text_out[63:0];

                end

        */

/*

always @(posedge clk)

                         begin

                                if(done2)

                                        begin

                                                text_out_64 <= text_out[63:0];

                                        end

                 end

*/

////////////////////////////////////////////////////////////////////

//

// Generic Functions

//

function [31:0] mix_col;

input   [7:0]    s0,s1,s2,s3;

//reg   [7:0]   s0_o,s1_o,s2_o,s3_o;

begin

mix_col[31:24]=xtime(s0)^xtime(s1)^s1^s2^s3;

mix_col[23:16]=s0^xtime(s1)^xtime(s2)^s2^s3;

mix_col[15:08]=s0^s1^xtime(s2)^xtime(s3)^s3;

mix_col[07:00]=xtime(s0)^s0^s1^s2^xtime(s3);

end

endfunction

function [7:0] xtime;

input [7:0] b; xtime={b[6:0],1'b0}^(8'h1b&{8{b[7]}});

endfunction

endmodule