//------------------------------------------------------------------------------
//
// tb_base_point_multiplier.v
// -----------------------------------------------------------------------------
// Testbench for Ed25519 base point scalar multiplier.
//
// Authors: Pavel Shatov
//
// Copyright (c) 2018, NORDUnet A/S
//
// 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 the NORDUnet 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 HOLDER 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.
//
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
`timescale 1ns / 1ps
//------------------------------------------------------------------------------
module tb_base_point_multiplier;
//
// Test Vectors
//
`include "ed25519_test_vectors.v"
//
// Core Parameters
//
localparam WORD_COUNTER_WIDTH = 3;
localparam OPERAND_NUM_WORDS = 8;
//
// Clock (100 MHz)
//
`define CLOCK_PERIOD 10.0
`define CLOCK_HALF_PERIOD (0.5 * `CLOCK_PERIOD)
reg clk = 1'b0;
always #`CLOCK_HALF_PERIOD clk = ~clk;
//
// Inputs, Outputs
//
reg rst_n;
reg ena;
wire rdy;
//
// Buffers (K, QY)
//
wire [WORD_COUNTER_WIDTH-1:0] core_k_addr;
wire [WORD_COUNTER_WIDTH-1:0] core_qy_addr;
wire core_qy_wren;
wire [ 32-1:0] core_k_data;
wire [ 32-1:0] core_qy_data;
reg [WORD_COUNTER_WIDTH-1:0] tb_k_addr;
reg [WORD_COUNTER_WIDTH-1:0] tb_qy_addr;
reg tb_k_wren;
reg [ 32-1:0] tb_k_data;
wire [ 32-1:0] tb_qy_data;
bram_1rw_1ro_readfirst # (.MEM_WIDTH(32), .MEM_ADDR_BITS(WORD_COUNTER_WIDTH))
bram_k
( .clk(clk),
.a_addr(tb_k_addr), .a_wr(tb_k_wren), .a_in(tb_k_data), .a_out(),
.b_addr(core_k_addr), .b_out(core_k_data)
);
bram_1rw_1ro_readfirst # (.MEM_WIDTH(32), .MEM_ADDR_BITS(WORD_COUNTER_WIDTH))
bram_qy
( .clk(clk),
.a_addr(core_qy_addr), .a_wr(core_qy_wren), .a_in(core_qy_data), .a_out(),
.b_addr(tb_qy_addr), .b_out(tb_qy_data)
);
//
// UUT
//
ed25519_multiplier uut
(
.clk (clk),
.rst_n (rst_n),
.ena (ena),
.rdy (rdy),
.k_addr (core_k_addr),
.qy_addr (core_qy_addr),
.qy_wren (core_qy_wren),
.k_din (core_k_data),
.qy_dout (core_qy_data)
);
//
// Testbench Routine
//
reg ok = 1;
initial begin
/* initialize control inputs */
rst_n = 0;
ena = 0;
/* wait for some time */
#200;
/* de-assert reset */
rst_n = 1;
/* wait for some time */
#100;
/* run tests */
$display("1. Q = d * G...");
test_base_point_multiplier(ED25519_D_HASHED_LSB_1, ED25519_Q_Y_1);
$display("2. Q = d * G...");
test_base_point_multiplier(ED25519_D_HASHED_LSB_2, ED25519_Q_Y_2);
$display("3. Q = d * G...");
test_base_point_multiplier(ED25519_D_HASHED_LSB_3, ED25519_Q_Y_3);
$display("4. Q = d * G...");
test_base_point_multiplier(ED25519_D_HASHED_LSB_4, ED25519_Q_Y_4);
$display("5. Q = d * G...");
test_base_point_multiplier(ED25519_D_HASHED_LSB_5, ED25519_Q_Y_5);
/* print result */
if (ok) $display("tb_base_point_multiplier: SUCCESS");
else $display("tb_base_point_multiplier: FAILURE");
//
#10000;
//
//$finish;
//
end
//
// Test Task
//
task test_base_point_multiplier;
input [255:0] k;
input [255:0] qy;
reg [255:0] k_shreg;
reg [255:0] qy_shreg;
reg qy_ok;
reg [255:0] qy_shreg_rev;
integer w;
begin
/* initialize result */
qy_ok = 0;
/* initialize shift registers */
k_shreg = k;
/* start filling memories */
tb_k_wren = 1;
/* write all the words */
for (w=0; w<OPERAND_NUM_WORDS; w=w+1) begin
/* set addresses */
tb_k_addr = w[WORD_COUNTER_WIDTH-1:0];
/* set data words */
tb_k_data = k_shreg[31:0];
/* shift inputs */
k_shreg = {{32{1'bX}}, k_shreg[255:32]};
/* wait for 1 clock tick */
#`CLOCK_PERIOD;
end
/* stop filling memories */
tb_k_wren = 0;
/* wipe addresses */
tb_k_addr = {WORD_COUNTER_WIDTH{1'bX}};
/* wipe data words */
tb_k_data = {32{1'bX}};
/* start operation */
ena = 1;
/* clear flag */
#`CLOCK_PERIOD ena = 0;
/* wait for operation to complete */
while (!rdy) #`CLOCK_PERIOD;
/* read result */
for (w=0; w<OPERAND_NUM_WORDS; w=w+1) begin
/* set address */
tb_qy_addr = w[WORD_COUNTER_WIDTH-1:0];
/* wait for 1 clock tick */
#`CLOCK_PERIOD
/* store data word */
qy_shreg = {tb_qy_data, qy_shreg[255:32]};
end
/* for some reason reference values in the RFC have different
* byte order, thus we need to reverse our result */
#`CLOCK_PERIOD;
for (w=0; w<4*OPERAND_NUM_WORDS; w=w+1) begin
/* shift right by 8 bits */
qy_shreg = {qy_shreg[7:0], qy_shreg[255:8]};
/* shift left by 8 bits */
qy_shreg_rev = {qy_shreg_rev[255-8:0], qy_shreg[255-:8]};
end
/* compare */
qy_ok = (qy_shreg_rev == qy);
/* display results */
if (qy_ok) $display("test_base_point_multiplier(): CORRECT RESULT");
else begin
$display("test_base_point_multiplier(): WRONG RESULT");
$display("REF: %x", qy);
$display("OUT: %x", qy_shreg_rev);
$display("XOR: %x", qy_shreg_rev ^ qy);
end
/* update global flag */
ok = ok & qy_ok;
end
endtask
endmodule
//------------------------------------------------------------------------------
// End-of-File
//------------------------------------------------------------------------------
