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`include "../bench/timescale.v"
// this moduel do a decrypt group
 
module group_decrypt(
                          input                    clk
                        , input                    rst
                        , input                    en
                        , input                    dec
                        , input                    init
                        , input         [ 8*8-1:0] ck
                        , input         [56*8-1:0] kk
                        , input         [ 8*8-1:0] group
                        , input         [   4-1:0] bytes
 
                        , output                   valid
                        , output        [ 8*8-1:0] ogroup
                        , output        [   4-1:0] obytes
                );
 
        reg init_d;
        wire [8*8-1:0] stream;
        reg  [8*8-1:0] stream_d;
        wire [8*8-1:0] ib;
        reg  [8*8-1:0] bco_d;
        wire  [8*8-1:0] bco;
        reg en_d;
 
 
        always @(posedge clk)
                begin
                en_d<=en;
                init_d<=init;
                if(en)
                begin
                        stream_d<=stream;
                end
                if(en_d)
                        bco_d<=bco;
 
                end
 
assign ib=(init_d)?group:group^stream;
 
 
stream_cypher stream_cypher(
                    .clk   (clk)
                  , .rst   (rst)
                  , .en    (en)
                  , .init  (init)
                  , .ck    (ck)
                  , .sb    (group)
                  , .cb    (stream)
                  );
 
block_decypher block_decypher(
                          .kk (kk)
                        , .ib (ib)
                        , .bd (bco)
                        );
 
assign ogroup=group^bco_d^stream;
 
assign valid=en_d & ~init_d;
assign obytes=4'h8;
 
 
endmodule