Subversion Repositories mod_mult_exp

-----------------------------------------------------------------------

----                                                               ----

---- Montgomery modular multiplier and exponentiator               ----

----                                                               ----

---- This file is part of the Montgomery modular multiplier        ----

---- and exponentiator project                                     ----

---- http://opencores.org/project,mod_mult_exp                     ----

----                                                               ----

---- Description:                                                  ----

----   Montgomery modular exponentiator main module. It combines   ----

----   all subomponents. It takes four numbers as the input:       ----

----   base, power, modulus and Montgomery residuum                ----

----   (2^(2*word_length) mod N) and results the modular           ----

----   exponentiation A^B mod M.                                   ----

----   In fact input data are read through one input controlled by ----

----   the ctrl input.                                             ----

---- To Do:                                                        ----

----                                                               ----

---- Author(s):                                                    ----

---- - Krzysztof Gajewski, gajos@opencores.org                     ----

----                       k.gajewski@gmail.com                    ----

----                                                               ----

-----------------------------------------------------------------------

----                                                               ----

---- Copyright (C) 2014 Authors and OPENCORES.ORG                  ----

----                                                               ----

---- 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 source file is free software; you can redistribute it    ----

---- and-or modify it under the terms of the GNU Lesser General    ----

---- Public License as published by the Free Software Foundation;  ----

---- either version 2.1 of the License, or (at your option) any    ----

---- later version.                                                ----

----                                                               ----

---- This source is distributed in the hope that it will be        ----

---- useful, but WITHOUT ANY WARRANTY; without even the implied    ----

---- warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR       ----

---- PURPOSE. See the GNU Lesser General Public License for more   ----

---- details.                                                      ----

----                                                               ----

---- You should have received a copy of the GNU Lesser General     ----

---- Public License along with this source; if not, download it    ----

---- from http://www.opencores.org/lgpl.shtml                      ----

----                                                               ----

-----------------------------------------------------------------------

library IEEE;

use work.properties.ALL;

use IEEE.STD_LOGIC_1164.ALL;

-- Uncomment the following library declaration if using

-- arithmetic functions with Signed or Unsigned values

--use IEEE.NUMERIC_STD.ALL;

-- Uncomment the following library declaration if instantiating

-- any Xilinx primitives in this code.

--library UNISIM;

--use UNISIM.VComponents.all;

entity ModExp is

    generic (

        word_size   : integer := WORD_LENGTH;

        word_binary : integer := WORD_INTEGER

    );

    Port (

        input         : in  STD_LOGIC_VECTOR(word_size - 1 downto 0);

        ctrl          : in  STD_LOGIC_VECTOR(2 downto 0);

        clk           : in  STD_LOGIC;

        reset         : in  STD_LOGIC;

        data_in_ready : in  STD_LOGIC;

        ready         : out STD_LOGIC;

        output        : out STD_LOGIC_VECTOR(word_size - 1 downto 0)

    );

end ModExp;

architecture Behavioral of ModExp is

-- Montgomery modular multiplier component

component ModularMultiplierIterative is

    generic (

        word_size : integer := WORD_LENGTH

    );

    port (

        A       : in  STD_LOGIC_VECTOR(word_size - 1 downto 0);     -- multiplicand

        B       : in  STD_LOGIC_VECTOR(word_size - 1 downto 0);     -- multiplier

        M       : in  STD_LOGIC_VECTOR(word_size - 1 downto 0);     -- modulus

        start   : in  STD_LOGIC;

        product : out STD_LOGIC_VECTOR(word_size - 1 downto 0); -- product

        ready   : out STD_LOGIC;

        clk     : in  STD_LOGIC

    );

end component ModularMultiplierIterative;

-- Block memory component generated through ISE

-- It is used like multiple cell register

COMPONENT blockMemory

    PORT (

        clka  : in  STD_LOGIC;

        rsta  : in  STD_LOGIC;

        wea   : in  STD_LOGIC_VECTOR(0 DOWNTO 0);

        addra : in  STD_LOGIC_VECTOR(3 DOWNTO 0);

        dina  : in  STD_LOGIC_VECTOR(word_size - 1 DOWNTO 0);

        douta : out STD_LOGIC_VECTOR(word_size - 1 DOWNTO 0)

    );

END COMPONENT;

-- Register

component Reg is

    generic(

        word_size : integer := WORD_LENGTH

    );

    port(

        input  : in  STD_LOGIC_VECTOR(word_size - 1 downto 0);

        output : out STD_LOGIC_VECTOR(word_size - 1 downto 0);

        enable : in  STD_LOGIC;

        clk    : in  STD_LOGIC;

        reset  : in  STD_LOGIC

    );

end component Reg;

-- Multiplexer

component MontMult4inMux is

    generic (

        word_size : integer := WORD_LENGTH - 1

    );

    port (

        ctrl   : in  STD_LOGIC_VECTOR(1 downto 0);

        zero   : in  STD_LOGIC_VECTOR(word_size downto 0);

        M      : in  STD_LOGIC_VECTOR(word_size downto 0);

        Y      : in  STD_LOGIC_VECTOR(word_size downto 0);

        YplusM : in  STD_LOGIC_VECTOR(word_size downto 0);

        output : out STD_LOGIC_VECTOR(word_size downto 0)

    );

end component MontMult4inMux;

-- State machine

component ModExpSM is

    generic(

        word_size : integer := WORD_LENGTH;

        word_binary : integer := WORD_INTEGER

    );

    port (

        data_in_ready  : in  STD_LOGIC;

        clk            : in  STD_LOGIC;

        exp_ctrl       : in  STD_LOGIC_VECTOR(2 downto 0);

        reset          : in  STD_LOGIC;

        in_mux_control : out STD_LOGIC_VECTOR(1 downto 0);

        -- finalizer end status

        ready          : out STD_LOGIC;

        -- control for multiplier

        modMultStart   : out STD_LOGIC;

        modMultReady   : in  STD_LOGIC;

        -- control for memory and registers

        addr_dataA     : out STD_LOGIC_VECTOR(3 downto 0);

        addr_dataB     : out STD_LOGIC_VECTOR(3 downto 0);

        regData_EnA    : out STD_LOGIC_VECTOR(0 downto 0);

        regData_EnB    : out STD_LOGIC_VECTOR(0 downto 0);

        regData_EnC    : out STD_LOGIC;

        regData_EnExponent   : out STD_LOGIC;

        ExponentData         : in  STD_LOGIC_VECTOR(word_size - 1 downto 0);

        memory_reset   : out STD_LOGIC

    );

end component ModExpSM;

-- data registers signals

signal addr_dataA : STD_LOGIC_VECTOR(3 downto 0);

signal addr_dataB : STD_LOGIC_VECTOR(3 downto 0);

signal memDataLoadA  : STD_LOGIC_VECTOR(0 downto 0);

signal memDataLoadB  : STD_LOGIC_VECTOR(0 downto 0);

signal memDataLoadC  : STD_LOGIC;

signal memDataLoadExponent : STD_LOGIC;

signal memDataA  : STD_LOGIC_VECTOR(word_size - 1 downto 0);

signal memDataB  : STD_LOGIC_VECTOR(word_size - 1 downto 0);

signal memDataC  : STD_LOGIC_VECTOR(word_size - 1 downto 0);

signal memDataExponent : STD_LOGIC_VECTOR(word_size - 1 downto 0);

signal memoryIn  : STD_LOGIC_VECTOR(word_size - 1 downto 0);

signal in_mux_control : STD_LOGIC_VECTOR(1 downto 0);

-- signal for multiplier

signal multStart       : STD_LOGIC;

signal multReady       : STD_LOGIC;

signal modMultToBuffer : STD_LOGIC_VECTOR(word_size - 1 downto 0);

signal zero : STD_LOGIC_VECTOR(word_size - 1 downto 0) := (others => '0');

signal one  : STD_LOGIC_VECTOR(word_size - 1 downto 0) := (0 => '1', others => '0');

signal memory_reset : STD_LOGIC;

begin

    -- connections between components

    zero <= (others => '0');

    one <=  (0 => '1', others => '0');

    -- Montgomery modular multiplier component

    modMult : ModularMultiplierIterative

    port map (

        A       => memDataA,

        B       => memDataB,

        M       => memDataC,

        start   => multStart,

        product => modMultToBuffer,

        ready   => multReady,

        clk     => clk

    );

    -- Multiplexer

    mux : MontMult4inMux

    port map (

        ctrl   => in_mux_control,

        zero   => zero,

        M      => one,

        Y      => modMultToBuffer,

        YplusM => input,

        output => memoryIn

    );

    -- Block memory for the first input of the multiplier

    memoryA : blockMemory

    port map (

        clka  => clk,

        rsta  => memory_reset,

        wea   => memDataLoadA,

        addra => addr_dataA,

        dina  => memoryIn,

        douta => memDataA

    );

    -- Block memory for the second input of the multiplier

    memoryB : blockMemory

    port map (

        clka  => clk,

        rsta  => memory_reset,

        wea   => memDataLoadB,

        addra => addr_dataB,

        dina  => memoryIn,

        douta => memDataB

    );

    -- Register for the modulus for the multiplier

    memoryModulus : Reg

    port map (

        input  => memoryIn,

        output => memDataC,

        enable => memDataLoadC,

        clk    => clk,

        reset  => memory_reset

    );

    -- Register for the exponent - it feeds also the state machine for the control of the exponentiation process

    memoryExponent : Reg

    port map (

        input  => memoryIn,

        output => memDataExponent,

        enable => memDataLoadExponent,

        clk    => clk,

        reset  => memory_reset

    );

    -- State machine of the Montgomery modular exponentiator

    stateMachine : ModExpSM

    port map(

        data_in_ready  => data_in_ready,

        clk            => clk,

        exp_ctrl       => ctrl,

        reset          => reset,

        in_mux_control => in_mux_control,

        ready          => ready,

        modMultStart   => multStart,

        modMultReady   => multReady,

        addr_dataA     => addr_dataA,

        addr_dataB     => addr_dataB,

        regData_EnA    => memDataLoadA,

        regData_EnB    => memDataLoadB,

        regData_EnC    => memDataLoadC,

        regData_EnExponent   => memDataLoadExponent,

        ExponentData         => memDataExponent,

        memory_reset   => memory_reset

    );

    output <= memDataA;

end Behavioral;