├── img
    └── VERILOGO.png
├── simu
    ├── input.vc
    ├── Makefile
    ├── aes_192_sed.v
    ├── round.v
    ├── simulation.cpp
    ├── aes_192.v
    ├── veriraptor.cpp
    └── table.v
├── attack.sh
├── Makefile
├── attack_hack_ches21.py
├── README.md
├── .gitignore
└── LICENSE


/img/VERILOGO.png:
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https://raw.githubusercontent.com/kudelskisecurity/Verilaptor/HEAD/img/VERILOGO.png


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/simu/input.vc:
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1 | // This file typically lists flags required by a large project, e.g. include directories
2 | table.v round.v


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/attack.sh:
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 1 | #!/bin/bash
 2 | 
 3 | # Compute faults from simulation
 4 | ./simu/build/veriraptor
 5 | 
 6 | # DFA on AES 192
 7 | ROUNDKEY=$(./attack_hack_ches21.py)
 8 | 
 9 | echo Concatenated round keys:
10 | echo $ROUNDKEY
11 | echo 
12 | 
13 | # Result is the 1.5 last round key, still need to invert AES keyschedule with
14 | echo "[+] Inverse key schedule"
15 | ./Stark/aes_keyschedule $ROUNDKEY 11


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/Makefile:
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 1 | STARK_GIT = "https://github.com/SideChannelMarvels/Stark.git"
 2 | SUBDIRS = simu Stark
 3 | 
 4 | .PHONY: subdirs $(SUBDIRS)
 5 | 
 6 | subdirs: $(SUBDIRS)
 7 | 
 8 | simu:
 9 | 		$(MAKE) -C $@
10 | 
11 | Stark:
12 | 	@if [ ! -d $@ ] ;\
13 | 	then \
14 | 	  echo "Stark does not exist, fetching"; \
15 | 	  git clone $(STARK_GIT); \
16 | 	fi
17 | 	$(MAKE) -C $@
18 | 
19 | clean:
20 | 	@rm -vf tracefile_r10 tracefile_r11 tracefile_r10_convert
21 | 	$(MAKE) clean -C simu
22 | 	@rm -rvf Stark
23 | 


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/attack_hack_ches21.py:
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 1 | #!/usr/bin/env python3
 2 | import phoenixAES
 3 | from binascii import hexlify, unhexlify
 4 | import sys
 5 | 
 6 | # Redirect output.
 7 | sys.stdout = sys.stderr
 8 | 
 9 | print("[+] DFA on 13th round\n")
10 | subkey13 = phoenixAES.crack_file("tracefile_r11", verbose=0)
11 | 
12 | print("[+] DFA on 12th round\n")
13 | subkey12 = phoenixAES.crack_file("tracefile_r10", lastroundkeys=[unhexlify(subkey13)], verbose=0)
14 | 
15 | print()
16 | # Restore stdout
17 | sys.stdout = sys.__stdout__
18 | print(subkey12 + subkey13[0:16])
19 | 


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/README.md:
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 1 | <p align="center">
 2 | <img src="img/VERILOGO.png" width="300">
 3 | </p>
 4 | 
 5 | For more information read our [blog post](https://research.kudelskisecurity.com/2021/09/21/verilaptor-software-fault-simultation-in-hardware-designs/).
 6 | 
 7 | To run AES0 simulation:
 8 | ```bash
 9 | $ verilator -cc aes_192_sed.v -f input.vc --Mdir build -o simu --exe simulation.cpp
10 | $ make -C build/ -f Vaes_192_sed.mk simu
11 | $ ./build/simu
12 | ```
13 | 
14 | To run the full attack:
15 | ```bash
16 | $ make
17 | $ ./attack.sh
18 | ```
19 | 
20 | Make sure to use at least v0.0.4 of phoenixAES.
21 | 


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/.gitignore:
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 1 | # Prerequisites
 2 | *.d
 3 | 
 4 | # Object files
 5 | *.o
 6 | *.ko
 7 | *.obj
 8 | *.elf
 9 | 
10 | # Linker output
11 | *.ilk
12 | *.map
13 | *.exp
14 | 
15 | # Precompiled Headers
16 | *.gch
17 | *.pch
18 | 
19 | # Libraries
20 | *.lib
21 | *.a
22 | *.la
23 | *.lo
24 | 
25 | # Shared objects (inc. Windows DLLs)
26 | *.dll
27 | *.so
28 | *.so.*
29 | *.dylib
30 | 
31 | # Executables
32 | *.exe
33 | *.out
34 | *.app
35 | *.i*86
36 | *.x86_64
37 | *.hex
38 | 
39 | # Debug files
40 | *.dSYM/
41 | *.su
42 | *.idb
43 | *.pdb
44 | 
45 | # Kernel Module Compile Results
46 | *.mod*
47 | *.cmd
48 | .tmp_versions/
49 | modules.order
50 | Module.symvers
51 | Mkfile.old
52 | dkms.conf
53 | 


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/simu/Makefile:
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 1 | # ======= CONFIGURATION =======
 2 | 
 3 | # Output directory where the final executable will be produced
 4 | # and where files generated by Verilator are stored
 5 | BUILD_DIR=build
 6 | 
 7 | # Name of the generated executable
 8 | OUT=veriraptor
 9 | 
10 | # Top-level verilog module
11 | TOP=aes_192_sed.v
12 | 
13 | # C++ files
14 | CPP=veriraptor.cpp
15 | 
16 | # ======= BUILD RULES =======
17 | 
18 | # Name of .mk file generated by Verilator
19 | VERILATOR_MK=V$(basename $(TOP)).mk
20 | 
21 | all: design $(OUT)
22 | 
23 | design: $(TOP)
24 | 	verilator -cc $(TOP) -f input.vc --Mdir $(BUILD_DIR) -o $(OUT) --exe $(CPP)
25 | 
26 | $(OUT): design
27 | 	$(MAKE) -C $(BUILD_DIR) -f $(VERILATOR_MK) $(OUT)
28 | 
29 | sim:
30 | 	@$(BUILD_DIR)/$(OUT)
31 | 
32 | clean:
33 | 	rm -rf $(BUILD_DIR)
34 | 


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/simu/aes_192_sed.v:
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 1 | /*
 2 |  * Description:
 3 |  * AES is implemented in CTR mode.
 4 |  * Give 128 bit input to "p_c_text" (plain/cipher text).
 5 |  * Give 192 bit key to "key".
 6 |  * Give 128 initial vector to "state".
 7 |  *
 8 |  * Conditions: 
 9 |  * Don't give new inputs and start until assertion of out_valid.
10 |  * Start has to go from 0 to 1 for the correct starting.
11 |  * "state" value should be same for both encryption and decryption.
12 |  *
13 |  * sed: Serialized Encryption and Decryption
14 |  */
15 | 
16 | module aes_192_sed(clk, start, state, p_c_text, key, out, out_valid); 
17 |     input          clk;
18 |     input          start;
19 |     input  [127:0] state, p_c_text;
20 |     input  [191:0] key;
21 |     output [127:0] out;
22 |     output         out_valid;
23 | 	
24 |     wire    [127:0] out_temp;
25 |     wire     out_valid;
26 |     
27 |     // Instantiate the Unit Under Test (UUT)
28 | 	aes_192 uut (
29 | 		.clk(clk), 
30 | 		.start(start), 
31 | 		.state(state), 
32 | 		.key(key), 
33 | 		.out(out_temp),
34 | 		.out_valid(out_valid)
35 | 	);
36 | 
37 |     // Muxing p_c_text with output of AES core.
38 |     assign out = p_c_text ^ out_temp;
39 | 
40 | endmodule
41 | 
42 | 


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/simu/round.v:
--------------------------------------------------------------------------------
 1 | /*
 2 |  * Copyright 2012, Homer Hsing <homer.hsing@gmail.com>
 3 |  *
 4 |  * Licensed under the Apache License, Version 2.0 (the "License");
 5 |  * you may not use this file except in compliance with the License.
 6 |  * You may obtain a copy of the License at
 7 |  *
 8 |  * http://www.apache.org/licenses/LICENSE-2.0
 9 |  *
10 |  * Unless required by applicable law or agreed to in writing, software
11 |  * distributed under the License is distributed on an "AS IS" BASIS,
12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 |  * See the License for the specific language governing permissions and
14 |  * limitations under the License.
15 |  */
16 | 
17 | /* verilator lint_off UNOPTFLAT */
18 | 
19 | /* one AES round for every two clock cycles */
20 | module one_round (clk, state_in, key, state_out);
21 | input              clk;
22 | input      [127:0] state_in, key;
23 | output reg [127:0] state_out;
24 | wire       [31:0]  s0,  s1,  s2,  s3,
25 |            z0,  z1,  z2,  z3,
26 |            p00, p01, p02, p03,
27 |            p10, p11, p12, p13,
28 |            p20, p21, p22, p23,
29 |            p30, p31, p32, p33,
30 |            k0,  k1,  k2,  k3;
31 | 
32 | assign {k0, k1, k2, k3} = key;
33 | 
34 | assign {s0, s1, s2, s3} = state_in;
35 | 
36 | table_lookup
37 |     t0 (clk, s0, p00, p01, p02, p03),
38 |     t1 (clk, s1, p10, p11, p12, p13),
39 |     t2 (clk, s2, p20, p21, p22, p23),
40 |     t3 (clk, s3, p30, p31, p32, p33);
41 | 
42 | assign z0 = p00 ^ p11 ^ p22 ^ p33 ^ k0;
43 | assign z1 = p03 ^ p10 ^ p21 ^ p32 ^ k1;
44 | assign z2 = p02 ^ p13 ^ p20 ^ p31 ^ k2;
45 | assign z3 = p01 ^ p12 ^ p23 ^ p30 ^ k3;
46 | 
47 | always @ (posedge clk)
48 |     state_out <= {z0, z1, z2, z3};
49 | endmodule
50 | 
51 |     /* AES final round for every two clock cycles */
52 |     module final_round (clk, state_in, key_in, state_out);
53 | input              clk;
54 | input      [127:0] state_in;
55 | input      [127:0] key_in;
56 | output reg [127:0] state_out;
57 | wire [31:0] s0,  s1,  s2,  s3,
58 |      z0,  z1,  z2,  z3,
59 |      k0,  k1,  k2,  k3;
60 | wire [7:0]  p00, p01, p02, p03,
61 |      p10, p11, p12, p13,
62 |      p20, p21, p22, p23,
63 |      p30, p31, p32, p33;
64 | 
65 | assign {k0, k1, k2, k3} = key_in;
66 | 
67 | assign {s0, s1, s2, s3} = state_in;
68 | 
69 | S4
70 |     S4_1 (clk, s0, {p00, p01, p02, p03}),
71 |     S4_2 (clk, s1, {p10, p11, p12, p13}),
72 |     S4_3 (clk, s2, {p20, p21, p22, p23}),
73 |     S4_4 (clk, s3, {p30, p31, p32, p33});
74 | 
75 | assign z0 = {p00, p11, p22, p33} ^ k0;
76 | assign z1 = {p10, p21, p32, p03} ^ k1;
77 | assign z2 = {p20, p31, p02, p13} ^ k2;
78 | assign z3 = {p30, p01, p12, p23} ^ k3;
79 | 
80 | always @ (posedge clk)
81 |     state_out <= {z0, z1, z2, z3};
82 | endmodule
83 | 
84 | 


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/simu/simulation.cpp:
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  1 | #include <iostream>
  2 | #include <verilated.h>
  3 | #include <assert.h>
  4 | #include <memory>
  5 | #include <iomanip>
  6 | #include <fstream>
  7 | 
  8 | #include "Vaes_192_sed.h"
  9 | 
 10 | template <typename T>
 11 | 
 12 | void userIn(const char * var_name, T & var)
 13 | {
 14 |     unsigned tmp;
 15 |     std::cout << var_name << " = ";
 16 |     std::cin >> tmp;
 17 |     assert(tmp <= 0xffffffff);
 18 |     var = tmp;
 19 | }
 20 | 
 21 | void userOut(const char * var_name, unsigned value)
 22 | {
 23 |     std::cout << var_name << " = " << std::hex << value << '\n';
 24 | }
 25 | 
 26 | void write_result(std::unique_ptr<Vaes_192_sed>& top, std::ofstream& file) {
 27 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[3];
 28 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[2];
 29 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[1];
 30 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[0] << '\n';;
 31 | }
 32 | 
 33 | void tick(std::unique_ptr<Vaes_192_sed>& top) {
 34 |     top->clk = 0;
 35 |     top->eval();
 36 |     top->clk = 1;
 37 |     top->eval();
 38 |     top->clk = 0;
 39 | }
 40 | 
 41 | void aes_encrypt(std::unique_ptr<Vaes_192_sed>& top) {
 42 |     tick(top);
 43 |     top->start = 0x1;
 44 |     tick(top);
 45 |     top->start = 0x0;
 46 |     tick(top);
 47 | 
 48 |     while (top->out_valid == 0) {
 49 |         tick(top);
 50 |     }
 51 | }
 52 | 
 53 | int main(int argc, char ** argv)
 54 | {
 55 |     int i;
 56 |     
 57 |     /* Initialize Verilator variables */
 58 |     Verilated::commandArgs(argc, argv);
 59 | 
 60 |     /* Create top module instance */
 61 |     auto top = std::make_unique<Vaes_192_sed>();
 62 | 
 63 |     std::cout << "[+] Simulation with Verilator\n";
 64 |     /* Inputs
 65 |     key: 8e73b0f7 da0e6452 c810f32b 809079e5 62f8ead2 522c6b7b
 66 |     plaintext:  6bc1bee2 2e409f96 e93d7e11 7393172a
 67 |     ciphertext: bd334f1d 6e45f25f f712a214 571fa5cc*/
 68 |     top->key[5] = 0x8e73b0f7;
 69 |     top->key[4] = 0xda0e6452;
 70 |     top->key[3] = 0xc810f32b;
 71 |     top->key[2] = 0x809079e5;
 72 |     top->key[1] = 0x62f8ead2;
 73 |     top->key[0] = 0x522c6b7b;
 74 | 
 75 |     top->state[3] = 0x6bc1bee2;
 76 |     top->state[2] = 0x2e409f96;
 77 |     top->state[1] = 0xe93d7e11;
 78 |     top->state[0] = 0x7393172a;
 79 | 
 80 |     std::cout << "Using key:\n";
 81 |     for (i=5;i>=0;i--) {
 82 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->key[i];
 83 |     }
 84 | 
 85 |     std::cout << "\nUsing plaintext:\n";
 86 |     for (i=3;i>=0;i--) {
 87 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->state[i];
 88 |     }
 89 | 
 90 |     aes_encrypt(top);
 91 | 
 92 |     std::cout << "\nResulting ciphertext:\n";
 93 |     for (i=3;i>=0;i--) {
 94 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->out[i];
 95 |     }
 96 |     std::cout << "\n\n";
 97 |     top->final();
 98 | 
 99 |     return 0;
100 | }
101 | 


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/simu/aes_192.v:
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  1 | /*
  2 |  * Copyright 2012, Homer Hsing <homer.hsing@gmail.com>
  3 |  *
  4 |  * Licensed under the Apache License, Version 2.0 (the "License");
  5 |  * you may not use this file except in compliance with the License.
  6 |  * You may obtain a copy of the License at
  7 |  *
  8 |  * http://www.apache.org/licenses/LICENSE-2.0
  9 |  *
 10 |  * Unless required by applicable law or agreed to in writing, software
 11 |  * distributed under the License is distributed on an "AS IS" BASIS,
 12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 13 |  * See the License for the specific language governing permissions and
 14 |  * limitations under the License.
 15 |  */
 16 | 
 17 | module aes_192 (clk, start, state, key, out, out_valid);
 18 | input          clk;
 19 | input          start;
 20 | input  [127:0] state;
 21 | input  [191:0] key;
 22 | output [127:0] out;
 23 | output         out_valid;
 24 | reg    [127:0] s0;
 25 | reg    [191:0] k0;
 26 | wire   [127:0] s1, s2, s3, s4, s5, s6, s7, s8, s9, s10, s11;
 27 | wire   [191:0] k1, k2, k3, k4, k5, k6, k7, k8, k9, k10, k11;
 28 | wire   [127:0] k0b, k1b, k2b, k3b, k4b, k5b, k6b, k7b, k8b, k9b, k10b, k11b;
 29 | 
 30 | reg start_r;
 31 | always @(posedge clk)
 32 |     begin
 33 |         start_r <= start;
 34 |     end
 35 | 
 36 | wire start_posedge = start & ~start_r;
 37 | reg [4:0] validCounter;
 38 | 
 39 | always @ (posedge clk)
 40 |     begin
 41 |         if(start_posedge)
 42 |             begin
 43 |                 s0 <= state ^ key[191:64];
 44 |                 k0 <= key;
 45 |                 validCounter <= 25;
 46 |             end
 47 |         else if(~out_valid)
 48 |             begin
 49 |                 validCounter <= validCounter - 1;
 50 |             end
 51 |     end
 52 | 
 53 | assign out_valid = (validCounter == 0);
 54 | 
 55 | expand_key_type_D_192  a0 (clk, k0, 8'h1,   k1,  k0b);
 56 | expand_key_type_B_192  a1 (clk, k1,         k2,  k1b);
 57 | expand_key_type_A_192  a2 (clk, k2, 8'h2,   k3,  k2b);
 58 | expand_key_type_C_192  a3 (clk, k3, 8'h4,   k4,  k3b);
 59 | expand_key_type_B_192  a4 (clk, k4,         k5,  k4b);
 60 | expand_key_type_A_192  a5 (clk, k5, 8'h8,   k6,  k5b);
 61 | expand_key_type_C_192  a6 (clk, k6, 8'h10,  k7,  k6b);
 62 | expand_key_type_B_192  a7 (clk, k7,         k8,  k7b);
 63 | expand_key_type_A_192  a8 (clk, k8, 8'h20,  k9,  k8b);
 64 | expand_key_type_C_192  a9 (clk, k9, 8'h40, k10,  k9b);
 65 | expand_key_type_B_192 a10 (clk,k10,        k11, k10b);
 66 | expand_key_type_A_192 a11 (clk,k11, 8'h80,    , k11b);
 67 | 
 68 | one_round
 69 |     r1 (clk, s0, k0b, s1),
 70 |     r2 (clk, s1, k1b, s2),
 71 |     r3 (clk, s2, k2b, s3),
 72 |     r4 (clk, s3, k3b, s4),
 73 |     r5 (clk, s4, k4b, s5),
 74 |     r6 (clk, s5, k5b, s6),
 75 |     r7 (clk, s6, k6b, s7),
 76 |     r8 (clk, s7, k7b, s8),
 77 |     r9 (clk, s8, k8b, s9),
 78 |     r10 (clk, s9, k9b, s10),
 79 |     r11 (clk, s10, k10b, s11);
 80 | 
 81 | final_round
 82 |     rf (clk, s11, k11b, out);
 83 | endmodule
 84 | 
 85 |     /* expand k0,k1,k2,k3 for every two clock cycles */
 86 |     module expand_key_type_A_192 (clk, in, rcon, out_1, out_2);
 87 | input              clk;
 88 | input      [191:0] in;
 89 | input      [7:0]   rcon;
 90 | output reg [191:0] out_1;
 91 | output     [127:0] out_2;
 92 | wire       [31:0]  k0, k1, k2, k3, k4, k5,
 93 |            v0, v1, v2, v3;
 94 | reg        [31:0]  k0a, k1a, k2a, k3a, k4a, k5a;
 95 | wire       [31:0]  k0b, k1b, k2b, k3b, k4b, k5b, k6a;
 96 | 
 97 | assign {k0, k1, k2, k3, k4, k5} = in;
 98 | 
 99 | assign v0 = {k0[31:24] ^ rcon, k0[23:0]};
100 | assign v1 = v0 ^ k1;
101 | assign v2 = v1 ^ k2;
102 | assign v3 = v2 ^ k3;
103 | 
104 | always @ (posedge clk)
105 |     {k0a, k1a, k2a, k3a, k4a, k5a} <= {v0, v1, v2, v3, k4, k5};
106 | 
107 | S4
108 |     S4_0 (clk, {k5[23:0], k5[31:24]}, k6a);
109 | 
110 | assign k0b = k0a ^ k6a;
111 | assign k1b = k1a ^ k6a;
112 | assign k2b = k2a ^ k6a;
113 | assign k3b = k3a ^ k6a;
114 | assign {k4b, k5b} = {k4a, k5a};
115 | 
116 | always @ (posedge clk)
117 |     out_1 <= {k0b, k1b, k2b, k3b, k4b, k5b};
118 | 
119 | assign out_2 = {k0b, k1b, k2b, k3b};
120 | endmodule
121 | 
122 |     /* expand k2,k3,k4,k5 for every two clock cycles */
123 |     module expand_key_type_B_192 (clk, in, out_1, out_2);
124 | input              clk;
125 | input      [191:0] in;
126 | output reg [191:0] out_1;
127 | output     [127:0] out_2;
128 | wire       [31:0]  k0, k1, k2, k3, k4, k5,
129 |            v2, v3, v4, v5;
130 | reg        [31:0]  k0a, k1a, k2a, k3a, k4a, k5a;
131 | 
132 | assign {k0, k1, k2, k3, k4, k5} = in;
133 | 
134 | assign v2 = k1 ^ k2;
135 | assign v3 = v2 ^ k3;
136 | assign v4 = v3 ^ k4;
137 | assign v5 = v4 ^ k5;
138 | 
139 | always @ (posedge clk)
140 |     {k0a, k1a, k2a, k3a, k4a, k5a} <= {k0, k1, v2, v3, v4, v5};
141 | 
142 | always @ (posedge clk)
143 |     out_1 <= {k0a, k1a, k2a, k3a, k4a, k5a};
144 | 
145 | assign out_2 = {k2a, k3a, k4a, k5a};
146 | endmodule
147 | 
148 |     /* expand k0,k1,k4,k5 for every two clock cycles */
149 |     module expand_key_type_C_192 (clk, in, rcon, out_1, out_2);
150 | input              clk;
151 | input      [191:0] in;
152 | input      [7:0]   rcon;
153 | output reg [191:0] out_1;
154 | output     [127:0] out_2;
155 | wire       [31:0]  k0, k1, k2, k3, k4, k5,
156 |            v4, v5, v0, v1;
157 | reg        [31:0]  k0a, k1a, k2a, k3a, k4a, k5a;
158 | wire       [31:0]  k0b, k1b, k2b, k3b, k4b, k5b, k6a;
159 | 
160 | assign {k0, k1, k2, k3, k4, k5} = in;
161 | 
162 | assign v4 = k3 ^ k4;
163 | assign v5 = v4 ^ k5;
164 | assign v0 = {k0[31:24] ^ rcon, k0[23:0]};
165 | assign v1 = v0 ^ k1;
166 | 
167 | always @ (posedge clk)
168 |     {k0a, k1a, k2a, k3a, k4a, k5a} <= {v0, v1, k2, k3, v4, v5};
169 | 
170 | S4
171 |     S4_0 (clk, {v5[23:0], v5[31:24]}, k6a);
172 | 
173 | assign k0b = k0a ^ k6a;
174 | assign k1b = k1a ^ k6a;
175 | assign {k2b, k3b, k4b, k5b} = {k2a, k3a, k4a, k5a};
176 | 
177 | always @ (posedge clk)
178 |     out_1 <= {k0b, k1b, k2b, k3b, k4b, k5b};
179 | 
180 | assign out_2 = {k4b, k5b, k0b, k1b};
181 | endmodule
182 | 
183 |     /* expand k0,k1 for every two clock cycles */
184 |     module expand_key_type_D_192 (clk, in, rcon, out_1, out_2);
185 | input              clk;
186 | input      [191:0] in;
187 | input      [7:0]   rcon;
188 | output reg [191:0] out_1;
189 | output     [127:0] out_2;
190 | wire       [31:0]  k0, k1, k2, k3, k4, k5,
191 |            v0, v1;
192 | reg        [31:0]  k0a, k1a, k2a, k3a, k4a, k5a;
193 | wire       [31:0]  k0b, k1b, k2b, k3b, k4b, k5b, k6a;
194 | 
195 | assign {k0, k1, k2, k3, k4, k5} = in;
196 | 
197 | assign v0 = {k0[31:24] ^ rcon, k0[23:0]};
198 | assign v1 = v0 ^ k1;
199 | 
200 | always @ (posedge clk)
201 |     {k0a, k1a, k2a, k3a, k4a, k5a} <= {v0, v1, k2, k3, k4, k5};
202 | 
203 | S4
204 |     S4_0 (clk, {k5[23:0], k5[31:24]}, k6a);
205 | 
206 | assign k0b = k0a ^ k6a;
207 | assign k1b = k1a ^ k6a;
208 | assign {k2b, k3b, k4b, k5b} = {k2a, k3a, k4a, k5a};
209 | 
210 | always @ (posedge clk)
211 |     out_1 <= {k0b, k1b, k2b, k3b, k4b, k5b};
212 | 
213 | assign out_2 = {k4b, k5b, k0b, k1b};
214 | endmodule
215 | 


--------------------------------------------------------------------------------
/simu/veriraptor.cpp:
--------------------------------------------------------------------------------
  1 | #include <iostream>
  2 | #include <verilated.h>
  3 | #include <assert.h>
  4 | #include <memory>
  5 | #include <iomanip>
  6 | #include <chrono>
  7 | #include <random>
  8 | #include <fstream>
  9 | 
 10 | #include "Vaes_192_sed.h"
 11 | #include "Vaes_192_sed_aes_192_sed.h"
 12 | #include "Vaes_192_sed_aes_192.h"
 13 | #include "Vaes_192_sed_one_round.h"
 14 | #include "Vaes_192_sed_table_lookup.h"
 15 | #include "Vaes_192_sed_S.h"
 16 | #include "Vaes_192_sed_T.h"
 17 | 
 18 | 
 19 | template <typename T>
 20 | 
 21 | void userIn(const char * var_name, T & var)
 22 | {
 23 |     unsigned tmp;
 24 |     std::cout << var_name << " = ";
 25 |     std::cin >> tmp;
 26 |     assert(tmp <= 0xffffffff);
 27 |     var = tmp;
 28 | }
 29 | 
 30 | void userOut(const char * var_name, unsigned value)
 31 | {
 32 |     std::cout << var_name << " = " << std::hex << value << '\n';
 33 | }
 34 | 
 35 | void tick_fault_r9(std::unique_ptr<Vaes_192_sed>& top, int sbox_num, int value) {
 36 |     top->clk = 0;
 37 |     top->eval();
 38 |     // Inject fault at output of sbox
 39 |     switch (sbox_num) {
 40 |         case 0: {
 41 |             auto sbox = top->aes_192_sed->uut->r9->t0;
 42 |             sbox->p3 = sbox->p3 ^ value;
 43 |         }
 44 |         break;
 45 |         case 1: {
 46 |             auto sbox = top->aes_192_sed->uut->r9->t1;
 47 |             sbox->p3 = sbox->p3 ^ value;
 48 |         }
 49 |         break;
 50 |         case 2: {
 51 |             auto sbox = top->aes_192_sed->uut->r9->t2;
 52 |             sbox->p3 = sbox->p3 ^ value;
 53 |         }
 54 |         break;
 55 |         case 3: {
 56 |             auto sbox = top->aes_192_sed->uut->r9->t3;
 57 |             sbox->p3 = sbox->p3 ^ value;
 58 |         }
 59 |         break;
 60 |     }
 61 |     top->clk = 1;
 62 |     top->eval();
 63 |     top->clk = 0;
 64 | }
 65 | 
 66 | void tick_fault_r10(std::unique_ptr<Vaes_192_sed>& top, int sbox_num, int value) {
 67 |     top->clk = 0;
 68 |     top->eval();
 69 |     // Inject fault at output of sbox
 70 |     switch (sbox_num) {
 71 |         case 0: {
 72 |             auto sbox = top->aes_192_sed->uut->r10->t0;
 73 |             sbox->p3 = sbox->p3 ^ value;
 74 |         }
 75 |         break;
 76 |         case 1: {
 77 |             auto sbox = top->aes_192_sed->uut->r10->t1;
 78 |             sbox->p3 = sbox->p3 ^ value;
 79 |         }
 80 |         break;
 81 |         case 2: {
 82 |             auto sbox = top->aes_192_sed->uut->r10->t2;
 83 |             sbox->p3 = sbox->p3 ^ value;
 84 |         }
 85 |         break;
 86 |         case 3: {
 87 |             auto sbox = top->aes_192_sed->uut->r10->t3;
 88 |             sbox->p3 = sbox->p3 ^ value;
 89 |         }
 90 |         break;
 91 |     }
 92 |     top->clk = 1;
 93 |     top->eval();
 94 |     top->clk = 0;
 95 | }
 96 | 
 97 | void write_result(std::unique_ptr<Vaes_192_sed>& top, std::ofstream& file, bool verbose) {
 98 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[3];
 99 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[2];
100 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[1];
101 |     file << std::setw(8) << std::setfill('0') << std::hex << top->out[0] << '\n';
102 | 
103 |     if (verbose) {
104 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->out[3];
105 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->out[2];
106 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->out[1];
107 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->out[0] << '\n';
108 |     }
109 | }
110 | 
111 | void tick(std::unique_ptr<Vaes_192_sed>& top) {
112 |     top->clk = 0;
113 |     top->eval();
114 |     top->clk = 1;
115 |     top->eval();
116 |     top->clk = 0;
117 | }
118 | 
119 | void aes_encrypt(std::unique_ptr<Vaes_192_sed>& top) {
120 |     tick(top);
121 |     top->start = 0x1;
122 |     tick(top);
123 |     top->start = 0x0;
124 |     tick(top);
125 | 
126 |     while (top->out_valid == 0) {
127 |         tick(top);
128 |     }
129 | }
130 | 
131 | void aes_encrypt_fault_r9(std::unique_ptr<Vaes_192_sed>& top, int value, int fault) {
132 |     int i = 0;
133 |     tick(top);
134 |     top->start = 0x1;
135 |     tick(top);
136 |     top->start = 0x0;
137 |     tick(top);
138 | 
139 |     while (top->out_valid == 0) {
140 |         if (i < 9) {
141 |             tick(top);
142 |         } else {
143 |             tick_fault_r9(top, value, fault);
144 |         }
145 |         i++;
146 |     }
147 | }
148 | 
149 | void aes_encrypt_fault_r10(std::unique_ptr<Vaes_192_sed>& top, int value, int fault) {
150 |     int i = 0;
151 |     tick(top);
152 |     top->start = 0x1;
153 |     tick(top);
154 |     top->start = 0x0;
155 |     tick(top);
156 | 
157 |     while (top->out_valid == 0) {
158 |         if (i < 10) {
159 |             tick(top);
160 |         } else {
161 |             tick_fault_r10(top, value, fault);
162 |         }
163 |         i++;
164 |     }
165 | }
166 | 
167 | int main(int argc, char ** argv)
168 | {
169 |     bool verbose = false;
170 | 
171 |     if (argc > 1) {
172 |         if (std::string(argv[1]) == "-v") {
173 |             verbose = true;
174 |         }
175 |     }
176 | 
177 |     /* Initialize Verilator variables */
178 |     Verilated::commandArgs(argc, argv);
179 | 
180 |     /* Create top module instance */
181 |     auto top = std::make_unique<Vaes_192_sed>();
182 | 
183 |     /* PRNG */
184 |     unsigned seed = std::chrono::system_clock::now().time_since_epoch().count(); 
185 |     std::mt19937 g1 (seed);
186 |     int i=0;
187 |     std::ofstream fault_file;
188 | 
189 |     std::cout << "[+] Fault simulation with Verilator\n";
190 | 
191 |     std::cout << "Using key:\n";
192 |     for (i=5;i>=0;i--) {
193 |         top->key[i] = g1();
194 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->key[i];
195 |     }
196 | 
197 |     std::cout << "\nUsing plaintext:\n";
198 |     for (i=3;i>=0;i--) {
199 |         top->state[i] = g1();
200 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->state[i];
201 |     }
202 | 
203 |     fault_file.open("tracefile_r11");
204 | 
205 |     // Golden sample
206 |     aes_encrypt(top);
207 |     std::cout << "\nGetting ciphertext:\n";
208 |     for (i=3;i>=0;i--) {
209 |         std::cout << std::setw(8) << std::setfill('0') << std::hex << top->out[i];
210 |     }
211 |     std::cout << "\n\n";
212 |     write_result(top, fault_file, verbose);
213 | 
214 |     // Getting the faults in round 11
215 |     for (i=0;i<4;i++) {
216 |         aes_encrypt_fault_r10(top, i, g1() % 256);
217 |         write_result(top, fault_file, verbose);
218 |         aes_encrypt_fault_r10(top, i, g1() % 256);
219 |         write_result(top, fault_file, verbose);
220 |     }
221 | 
222 |     fault_file.close();
223 |     fault_file.open("tracefile_r10");
224 | 
225 |     // Golden sample
226 |     aes_encrypt(top);
227 |     write_result(top, fault_file, verbose);
228 | 
229 |     // Getting the faults in round 10
230 |     for (i=0;i<4;i++) {
231 |         aes_encrypt_fault_r9(top, i, g1() % 256);
232 |         write_result(top, fault_file, verbose);
233 | 
234 |         aes_encrypt_fault_r9(top, i, g1() % 256);
235 |         write_result(top, fault_file, verbose);
236 |     }
237 |     fault_file.close();
238 |     top->final();
239 | 
240 |     return 0;
241 | }
242 | 


--------------------------------------------------------------------------------
/simu/table.v:
--------------------------------------------------------------------------------
   1 | /*
   2 |  * Copyright 2012, Homer Hsing <homer.hsing@gmail.com>
   3 |  *
   4 |  * Licensed under the Apache License, Version 2.0 (the "License");
   5 |  * you may not use this file except in compliance with the License.
   6 |  * You may obtain a copy of the License at
   7 |  *
   8 |  * http://www.apache.org/licenses/LICENSE-2.0
   9 |  *
  10 |  * Unless required by applicable law or agreed to in writing, software
  11 |  * distributed under the License is distributed on an "AS IS" BASIS,
  12 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 |  * See the License for the specific language governing permissions and
  14 |  * limitations under the License.
  15 |  */
  16 | 
  17 | /* verilator lint_off UNOPTFLAT */
  18 | 
  19 | module table_lookup (clk, state, p0, p1, p2, p3);
  20 | input clk;
  21 | input [31:0] state;
  22 | output [31:0] p0, p1, p2, p3/*verilator public*/;
  23 | wire [7:0] b0, b1, b2, b3;
  24 | 
  25 | assign {b0, b1, b2, b3} = state;
  26 | T
  27 |     t0 (clk, b0, {p0[23:0], p0[31:24]}),
  28 |     t1 (clk, b1, {p1[15:0], p1[31:16]}),
  29 |     t2 (clk, b2, {p2[7:0],  p2[31:8]} ),
  30 |     t3 (clk, b3, p3);
  31 | endmodule
  32 | 
  33 |     /* substitue four bytes in a word */
  34 |     module S4 (clk, in, out);
  35 | input clk;
  36 | input [31:0] in;
  37 | output [31:0] out;
  38 | 
  39 | S
  40 |     S_0 (clk, in[31:24], out[31:24]),
  41 |     S_1 (clk, in[23:16], out[23:16]),
  42 |     S_2 (clk, in[15:8],  out[15:8] ),
  43 |     S_3 (clk, in[7:0],   out[7:0]  );
  44 | endmodule
  45 | 
  46 |     /* S_box, S_box, S_box*(x+1), S_box*x */
  47 |     module T (clk, in, out);
  48 | input         clk;
  49 | input  [7:0]  in;
  50 | output [31:0] out;
  51 | 
  52 | S
  53 |     s0 (clk, in, out[31:24]);
  54 | assign out[23:16] = out[31:24];
  55 | xS
  56 |     s4 (clk, in, out[7:0]);
  57 | assign out[15:8] = out[23:16] ^ out[7:0];
  58 | endmodule
  59 | 
  60 |     /* S box */
  61 |     module S (clk, in, out);
  62 | input clk;
  63 | input [7:0] in;
  64 | output reg [7:0] out;
  65 | 
  66 | always @ (posedge clk)
  67 |     case (in)
  68 |         8'h00:
  69 |             out <= 8'h63;
  70 |         8'h01:
  71 |             out <= 8'h7c;
  72 |         8'h02:
  73 |             out <= 8'h77;
  74 |         8'h03:
  75 |             out <= 8'h7b;
  76 |         8'h04:
  77 |             out <= 8'hf2;
  78 |         8'h05:
  79 |             out <= 8'h6b;
  80 |         8'h06:
  81 |             out <= 8'h6f;
  82 |         8'h07:
  83 |             out <= 8'hc5;
  84 |         8'h08:
  85 |             out <= 8'h30;
  86 |         8'h09:
  87 |             out <= 8'h01;
  88 |         8'h0a:
  89 |             out <= 8'h67;
  90 |         8'h0b:
  91 |             out <= 8'h2b;
  92 |         8'h0c:
  93 |             out <= 8'hfe;
  94 |         8'h0d:
  95 |             out <= 8'hd7;
  96 |         8'h0e:
  97 |             out <= 8'hab;
  98 |         8'h0f:
  99 |             out <= 8'h76;
 100 |         8'h10:
 101 |             out <= 8'hca;
 102 |         8'h11:
 103 |             out <= 8'h82;
 104 |         8'h12:
 105 |             out <= 8'hc9;
 106 |         8'h13:
 107 |             out <= 8'h7d;
 108 |         8'h14:
 109 |             out <= 8'hfa;
 110 |         8'h15:
 111 |             out <= 8'h59;
 112 |         8'h16:
 113 |             out <= 8'h47;
 114 |         8'h17:
 115 |             out <= 8'hf0;
 116 |         8'h18:
 117 |             out <= 8'had;
 118 |         8'h19:
 119 |             out <= 8'hd4;
 120 |         8'h1a:
 121 |             out <= 8'ha2;
 122 |         8'h1b:
 123 |             out <= 8'haf;
 124 |         8'h1c:
 125 |             out <= 8'h9c;
 126 |         8'h1d:
 127 |             out <= 8'ha4;
 128 |         8'h1e:
 129 |             out <= 8'h72;
 130 |         8'h1f:
 131 |             out <= 8'hc0;
 132 |         8'h20:
 133 |             out <= 8'hb7;
 134 |         8'h21:
 135 |             out <= 8'hfd;
 136 |         8'h22:
 137 |             out <= 8'h93;
 138 |         8'h23:
 139 |             out <= 8'h26;
 140 |         8'h24:
 141 |             out <= 8'h36;
 142 |         8'h25:
 143 |             out <= 8'h3f;
 144 |         8'h26:
 145 |             out <= 8'hf7;
 146 |         8'h27:
 147 |             out <= 8'hcc;
 148 |         8'h28:
 149 |             out <= 8'h34;
 150 |         8'h29:
 151 |             out <= 8'ha5;
 152 |         8'h2a:
 153 |             out <= 8'he5;
 154 |         8'h2b:
 155 |             out <= 8'hf1;
 156 |         8'h2c:
 157 |             out <= 8'h71;
 158 |         8'h2d:
 159 |             out <= 8'hd8;
 160 |         8'h2e:
 161 |             out <= 8'h31;
 162 |         8'h2f:
 163 |             out <= 8'h15;
 164 |         8'h30:
 165 |             out <= 8'h04;
 166 |         8'h31:
 167 |             out <= 8'hc7;
 168 |         8'h32:
 169 |             out <= 8'h23;
 170 |         8'h33:
 171 |             out <= 8'hc3;
 172 |         8'h34:
 173 |             out <= 8'h18;
 174 |         8'h35:
 175 |             out <= 8'h96;
 176 |         8'h36:
 177 |             out <= 8'h05;
 178 |         8'h37:
 179 |             out <= 8'h9a;
 180 |         8'h38:
 181 |             out <= 8'h07;
 182 |         8'h39:
 183 |             out <= 8'h12;
 184 |         8'h3a:
 185 |             out <= 8'h80;
 186 |         8'h3b:
 187 |             out <= 8'he2;
 188 |         8'h3c:
 189 |             out <= 8'heb;
 190 |         8'h3d:
 191 |             out <= 8'h27;
 192 |         8'h3e:
 193 |             out <= 8'hb2;
 194 |         8'h3f:
 195 |             out <= 8'h75;
 196 |         8'h40:
 197 |             out <= 8'h09;
 198 |         8'h41:
 199 |             out <= 8'h83;
 200 |         8'h42:
 201 |             out <= 8'h2c;
 202 |         8'h43:
 203 |             out <= 8'h1a;
 204 |         8'h44:
 205 |             out <= 8'h1b;
 206 |         8'h45:
 207 |             out <= 8'h6e;
 208 |         8'h46:
 209 |             out <= 8'h5a;
 210 |         8'h47:
 211 |             out <= 8'ha0;
 212 |         8'h48:
 213 |             out <= 8'h52;
 214 |         8'h49:
 215 |             out <= 8'h3b;
 216 |         8'h4a:
 217 |             out <= 8'hd6;
 218 |         8'h4b:
 219 |             out <= 8'hb3;
 220 |         8'h4c:
 221 |             out <= 8'h29;
 222 |         8'h4d:
 223 |             out <= 8'he3;
 224 |         8'h4e:
 225 |             out <= 8'h2f;
 226 |         8'h4f:
 227 |             out <= 8'h84;
 228 |         8'h50:
 229 |             out <= 8'h53;
 230 |         8'h51:
 231 |             out <= 8'hd1;
 232 |         8'h52:
 233 |             out <= 8'h00;
 234 |         8'h53:
 235 |             out <= 8'hed;
 236 |         8'h54:
 237 |             out <= 8'h20;
 238 |         8'h55:
 239 |             out <= 8'hfc;
 240 |         8'h56:
 241 |             out <= 8'hb1;
 242 |         8'h57:
 243 |             out <= 8'h5b;
 244 |         8'h58:
 245 |             out <= 8'h6a;
 246 |         8'h59:
 247 |             out <= 8'hcb;
 248 |         8'h5a:
 249 |             out <= 8'hbe;
 250 |         8'h5b:
 251 |             out <= 8'h39;
 252 |         8'h5c:
 253 |             out <= 8'h4a;
 254 |         8'h5d:
 255 |             out <= 8'h4c;
 256 |         8'h5e:
 257 |             out <= 8'h58;
 258 |         8'h5f:
 259 |             out <= 8'hcf;
 260 |         8'h60:
 261 |             out <= 8'hd0;
 262 |         8'h61:
 263 |             out <= 8'hef;
 264 |         8'h62:
 265 |             out <= 8'haa;
 266 |         8'h63:
 267 |             out <= 8'hfb;
 268 |         8'h64:
 269 |             out <= 8'h43;
 270 |         8'h65:
 271 |             out <= 8'h4d;
 272 |         8'h66:
 273 |             out <= 8'h33;
 274 |         8'h67:
 275 |             out <= 8'h85;
 276 |         8'h68:
 277 |             out <= 8'h45;
 278 |         8'h69:
 279 |             out <= 8'hf9;
 280 |         8'h6a:
 281 |             out <= 8'h02;
 282 |         8'h6b:
 283 |             out <= 8'h7f;
 284 |         8'h6c:
 285 |             out <= 8'h50;
 286 |         8'h6d:
 287 |             out <= 8'h3c;
 288 |         8'h6e:
 289 |             out <= 8'h9f;
 290 |         8'h6f:
 291 |             out <= 8'ha8;
 292 |         8'h70:
 293 |             out <= 8'h51;
 294 |         8'h71:
 295 |             out <= 8'ha3;
 296 |         8'h72:
 297 |             out <= 8'h40;
 298 |         8'h73:
 299 |             out <= 8'h8f;
 300 |         8'h74:
 301 |             out <= 8'h92;
 302 |         8'h75:
 303 |             out <= 8'h9d;
 304 |         8'h76:
 305 |             out <= 8'h38;
 306 |         8'h77:
 307 |             out <= 8'hf5;
 308 |         8'h78:
 309 |             out <= 8'hbc;
 310 |         8'h79:
 311 |             out <= 8'hb6;
 312 |         8'h7a:
 313 |             out <= 8'hda;
 314 |         8'h7b:
 315 |             out <= 8'h21;
 316 |         8'h7c:
 317 |             out <= 8'h10;
 318 |         8'h7d:
 319 |             out <= 8'hff;
 320 |         8'h7e:
 321 |             out <= 8'hf3;
 322 |         8'h7f:
 323 |             out <= 8'hd2;
 324 |         8'h80:
 325 |             out <= 8'hcd;
 326 |         8'h81:
 327 |             out <= 8'h0c;
 328 |         8'h82:
 329 |             out <= 8'h13;
 330 |         8'h83:
 331 |             out <= 8'hec;
 332 |         8'h84:
 333 |             out <= 8'h5f;
 334 |         8'h85:
 335 |             out <= 8'h97;
 336 |         8'h86:
 337 |             out <= 8'h44;
 338 |         8'h87:
 339 |             out <= 8'h17;
 340 |         8'h88:
 341 |             out <= 8'hc4;
 342 |         8'h89:
 343 |             out <= 8'ha7;
 344 |         8'h8a:
 345 |             out <= 8'h7e;
 346 |         8'h8b:
 347 |             out <= 8'h3d;
 348 |         8'h8c:
 349 |             out <= 8'h64;
 350 |         8'h8d:
 351 |             out <= 8'h5d;
 352 |         8'h8e:
 353 |             out <= 8'h19;
 354 |         8'h8f:
 355 |             out <= 8'h73;
 356 |         8'h90:
 357 |             out <= 8'h60;
 358 |         8'h91:
 359 |             out <= 8'h81;
 360 |         8'h92:
 361 |             out <= 8'h4f;
 362 |         8'h93:
 363 |             out <= 8'hdc;
 364 |         8'h94:
 365 |             out <= 8'h22;
 366 |         8'h95:
 367 |             out <= 8'h2a;
 368 |         8'h96:
 369 |             out <= 8'h90;
 370 |         8'h97:
 371 |             out <= 8'h88;
 372 |         8'h98:
 373 |             out <= 8'h46;
 374 |         8'h99:
 375 |             out <= 8'hee;
 376 |         8'h9a:
 377 |             out <= 8'hb8;
 378 |         8'h9b:
 379 |             out <= 8'h14;
 380 |         8'h9c:
 381 |             out <= 8'hde;
 382 |         8'h9d:
 383 |             out <= 8'h5e;
 384 |         8'h9e:
 385 |             out <= 8'h0b;
 386 |         8'h9f:
 387 |             out <= 8'hdb;
 388 |         8'ha0:
 389 |             out <= 8'he0;
 390 |         8'ha1:
 391 |             out <= 8'h32;
 392 |         8'ha2:
 393 |             out <= 8'h3a;
 394 |         8'ha3:
 395 |             out <= 8'h0a;
 396 |         8'ha4:
 397 |             out <= 8'h49;
 398 |         8'ha5:
 399 |             out <= 8'h06;
 400 |         8'ha6:
 401 |             out <= 8'h24;
 402 |         8'ha7:
 403 |             out <= 8'h5c;
 404 |         8'ha8:
 405 |             out <= 8'hc2;
 406 |         8'ha9:
 407 |             out <= 8'hd3;
 408 |         8'haa:
 409 |             out <= 8'hac;
 410 |         8'hab:
 411 |             out <= 8'h62;
 412 |         8'hac:
 413 |             out <= 8'h91;
 414 |         8'had:
 415 |             out <= 8'h95;
 416 |         8'hae:
 417 |             out <= 8'he4;
 418 |         8'haf:
 419 |             out <= 8'h79;
 420 |         8'hb0:
 421 |             out <= 8'he7;
 422 |         8'hb1:
 423 |             out <= 8'hc8;
 424 |         8'hb2:
 425 |             out <= 8'h37;
 426 |         8'hb3:
 427 |             out <= 8'h6d;
 428 |         8'hb4:
 429 |             out <= 8'h8d;
 430 |         8'hb5:
 431 |             out <= 8'hd5;
 432 |         8'hb6:
 433 |             out <= 8'h4e;
 434 |         8'hb7:
 435 |             out <= 8'ha9;
 436 |         8'hb8:
 437 |             out <= 8'h6c;
 438 |         8'hb9:
 439 |             out <= 8'h56;
 440 |         8'hba:
 441 |             out <= 8'hf4;
 442 |         8'hbb:
 443 |             out <= 8'hea;
 444 |         8'hbc:
 445 |             out <= 8'h65;
 446 |         8'hbd:
 447 |             out <= 8'h7a;
 448 |         8'hbe:
 449 |             out <= 8'hae;
 450 |         8'hbf:
 451 |             out <= 8'h08;
 452 |         8'hc0:
 453 |             out <= 8'hba;
 454 |         8'hc1:
 455 |             out <= 8'h78;
 456 |         8'hc2:
 457 |             out <= 8'h25;
 458 |         8'hc3:
 459 |             out <= 8'h2e;
 460 |         8'hc4:
 461 |             out <= 8'h1c;
 462 |         8'hc5:
 463 |             out <= 8'ha6;
 464 |         8'hc6:
 465 |             out <= 8'hb4;
 466 |         8'hc7:
 467 |             out <= 8'hc6;
 468 |         8'hc8:
 469 |             out <= 8'he8;
 470 |         8'hc9:
 471 |             out <= 8'hdd;
 472 |         8'hca:
 473 |             out <= 8'h74;
 474 |         8'hcb:
 475 |             out <= 8'h1f;
 476 |         8'hcc:
 477 |             out <= 8'h4b;
 478 |         8'hcd:
 479 |             out <= 8'hbd;
 480 |         8'hce:
 481 |             out <= 8'h8b;
 482 |         8'hcf:
 483 |             out <= 8'h8a;
 484 |         8'hd0:
 485 |             out <= 8'h70;
 486 |         8'hd1:
 487 |             out <= 8'h3e;
 488 |         8'hd2:
 489 |             out <= 8'hb5;
 490 |         8'hd3:
 491 |             out <= 8'h66;
 492 |         8'hd4:
 493 |             out <= 8'h48;
 494 |         8'hd5:
 495 |             out <= 8'h03;
 496 |         8'hd6:
 497 |             out <= 8'hf6;
 498 |         8'hd7:
 499 |             out <= 8'h0e;
 500 |         8'hd8:
 501 |             out <= 8'h61;
 502 |         8'hd9:
 503 |             out <= 8'h35;
 504 |         8'hda:
 505 |             out <= 8'h57;
 506 |         8'hdb:
 507 |             out <= 8'hb9;
 508 |         8'hdc:
 509 |             out <= 8'h86;
 510 |         8'hdd:
 511 |             out <= 8'hc1;
 512 |         8'hde:
 513 |             out <= 8'h1d;
 514 |         8'hdf:
 515 |             out <= 8'h9e;
 516 |         8'he0:
 517 |             out <= 8'he1;
 518 |         8'he1:
 519 |             out <= 8'hf8;
 520 |         8'he2:
 521 |             out <= 8'h98;
 522 |         8'he3:
 523 |             out <= 8'h11;
 524 |         8'he4:
 525 |             out <= 8'h69;
 526 |         8'he5:
 527 |             out <= 8'hd9;
 528 |         8'he6:
 529 |             out <= 8'h8e;
 530 |         8'he7:
 531 |             out <= 8'h94;
 532 |         8'he8:
 533 |             out <= 8'h9b;
 534 |         8'he9:
 535 |             out <= 8'h1e;
 536 |         8'hea:
 537 |             out <= 8'h87;
 538 |         8'heb:
 539 |             out <= 8'he9;
 540 |         8'hec:
 541 |             out <= 8'hce;
 542 |         8'hed:
 543 |             out <= 8'h55;
 544 |         8'hee:
 545 |             out <= 8'h28;
 546 |         8'hef:
 547 |             out <= 8'hdf;
 548 |         8'hf0:
 549 |             out <= 8'h8c;
 550 |         8'hf1:
 551 |             out <= 8'ha1;
 552 |         8'hf2:
 553 |             out <= 8'h89;
 554 |         8'hf3:
 555 |             out <= 8'h0d;
 556 |         8'hf4:
 557 |             out <= 8'hbf;
 558 |         8'hf5:
 559 |             out <= 8'he6;
 560 |         8'hf6:
 561 |             out <= 8'h42;
 562 |         8'hf7:
 563 |             out <= 8'h68;
 564 |         8'hf8:
 565 |             out <= 8'h41;
 566 |         8'hf9:
 567 |             out <= 8'h99;
 568 |         8'hfa:
 569 |             out <= 8'h2d;
 570 |         8'hfb:
 571 |             out <= 8'h0f;
 572 |         8'hfc:
 573 |             out <= 8'hb0;
 574 |         8'hfd:
 575 |             out <= 8'h54;
 576 |         8'hfe:
 577 |             out <= 8'hbb;
 578 |         8'hff:
 579 |             out <= 8'h16;
 580 |     endcase
 581 | endmodule
 582 | 
 583 |     /* S box * x */
 584 |     module xS (clk, in, out);
 585 | input clk;
 586 | input [7:0] in;
 587 | output reg [7:0] out;
 588 | 
 589 | always @ (posedge clk)
 590 |     case (in)
 591 |         8'h00:
 592 |             out <= 8'hc6;
 593 |         8'h01:
 594 |             out <= 8'hf8;
 595 |         8'h02:
 596 |             out <= 8'hee;
 597 |         8'h03:
 598 |             out <= 8'hf6;
 599 |         8'h04:
 600 |             out <= 8'hff;
 601 |         8'h05:
 602 |             out <= 8'hd6;
 603 |         8'h06:
 604 |             out <= 8'hde;
 605 |         8'h07:
 606 |             out <= 8'h91;
 607 |         8'h08:
 608 |             out <= 8'h60;
 609 |         8'h09:
 610 |             out <= 8'h02;
 611 |         8'h0a:
 612 |             out <= 8'hce;
 613 |         8'h0b:
 614 |             out <= 8'h56;
 615 |         8'h0c:
 616 |             out <= 8'he7;
 617 |         8'h0d:
 618 |             out <= 8'hb5;
 619 |         8'h0e:
 620 |             out <= 8'h4d;
 621 |         8'h0f:
 622 |             out <= 8'hec;
 623 |         8'h10:
 624 |             out <= 8'h8f;
 625 |         8'h11:
 626 |             out <= 8'h1f;
 627 |         8'h12:
 628 |             out <= 8'h89;
 629 |         8'h13:
 630 |             out <= 8'hfa;
 631 |         8'h14:
 632 |             out <= 8'hef;
 633 |         8'h15:
 634 |             out <= 8'hb2;
 635 |         8'h16:
 636 |             out <= 8'h8e;
 637 |         8'h17:
 638 |             out <= 8'hfb;
 639 |         8'h18:
 640 |             out <= 8'h41;
 641 |         8'h19:
 642 |             out <= 8'hb3;
 643 |         8'h1a:
 644 |             out <= 8'h5f;
 645 |         8'h1b:
 646 |             out <= 8'h45;
 647 |         8'h1c:
 648 |             out <= 8'h23;
 649 |         8'h1d:
 650 |             out <= 8'h53;
 651 |         8'h1e:
 652 |             out <= 8'he4;
 653 |         8'h1f:
 654 |             out <= 8'h9b;
 655 |         8'h20:
 656 |             out <= 8'h75;
 657 |         8'h21:
 658 |             out <= 8'he1;
 659 |         8'h22:
 660 |             out <= 8'h3d;
 661 |         8'h23:
 662 |             out <= 8'h4c;
 663 |         8'h24:
 664 |             out <= 8'h6c;
 665 |         8'h25:
 666 |             out <= 8'h7e;
 667 |         8'h26:
 668 |             out <= 8'hf5;
 669 |         8'h27:
 670 |             out <= 8'h83;
 671 |         8'h28:
 672 |             out <= 8'h68;
 673 |         8'h29:
 674 |             out <= 8'h51;
 675 |         8'h2a:
 676 |             out <= 8'hd1;
 677 |         8'h2b:
 678 |             out <= 8'hf9;
 679 |         8'h2c:
 680 |             out <= 8'he2;
 681 |         8'h2d:
 682 |             out <= 8'hab;
 683 |         8'h2e:
 684 |             out <= 8'h62;
 685 |         8'h2f:
 686 |             out <= 8'h2a;
 687 |         8'h30:
 688 |             out <= 8'h08;
 689 |         8'h31:
 690 |             out <= 8'h95;
 691 |         8'h32:
 692 |             out <= 8'h46;
 693 |         8'h33:
 694 |             out <= 8'h9d;
 695 |         8'h34:
 696 |             out <= 8'h30;
 697 |         8'h35:
 698 |             out <= 8'h37;
 699 |         8'h36:
 700 |             out <= 8'h0a;
 701 |         8'h37:
 702 |             out <= 8'h2f;
 703 |         8'h38:
 704 |             out <= 8'h0e;
 705 |         8'h39:
 706 |             out <= 8'h24;
 707 |         8'h3a:
 708 |             out <= 8'h1b;
 709 |         8'h3b:
 710 |             out <= 8'hdf;
 711 |         8'h3c:
 712 |             out <= 8'hcd;
 713 |         8'h3d:
 714 |             out <= 8'h4e;
 715 |         8'h3e:
 716 |             out <= 8'h7f;
 717 |         8'h3f:
 718 |             out <= 8'hea;
 719 |         8'h40:
 720 |             out <= 8'h12;
 721 |         8'h41:
 722 |             out <= 8'h1d;
 723 |         8'h42:
 724 |             out <= 8'h58;
 725 |         8'h43:
 726 |             out <= 8'h34;
 727 |         8'h44:
 728 |             out <= 8'h36;
 729 |         8'h45:
 730 |             out <= 8'hdc;
 731 |         8'h46:
 732 |             out <= 8'hb4;
 733 |         8'h47:
 734 |             out <= 8'h5b;
 735 |         8'h48:
 736 |             out <= 8'ha4;
 737 |         8'h49:
 738 |             out <= 8'h76;
 739 |         8'h4a:
 740 |             out <= 8'hb7;
 741 |         8'h4b:
 742 |             out <= 8'h7d;
 743 |         8'h4c:
 744 |             out <= 8'h52;
 745 |         8'h4d:
 746 |             out <= 8'hdd;
 747 |         8'h4e:
 748 |             out <= 8'h5e;
 749 |         8'h4f:
 750 |             out <= 8'h13;
 751 |         8'h50:
 752 |             out <= 8'ha6;
 753 |         8'h51:
 754 |             out <= 8'hb9;
 755 |         8'h52:
 756 |             out <= 8'h00;
 757 |         8'h53:
 758 |             out <= 8'hc1;
 759 |         8'h54:
 760 |             out <= 8'h40;
 761 |         8'h55:
 762 |             out <= 8'he3;
 763 |         8'h56:
 764 |             out <= 8'h79;
 765 |         8'h57:
 766 |             out <= 8'hb6;
 767 |         8'h58:
 768 |             out <= 8'hd4;
 769 |         8'h59:
 770 |             out <= 8'h8d;
 771 |         8'h5a:
 772 |             out <= 8'h67;
 773 |         8'h5b:
 774 |             out <= 8'h72;
 775 |         8'h5c:
 776 |             out <= 8'h94;
 777 |         8'h5d:
 778 |             out <= 8'h98;
 779 |         8'h5e:
 780 |             out <= 8'hb0;
 781 |         8'h5f:
 782 |             out <= 8'h85;
 783 |         8'h60:
 784 |             out <= 8'hbb;
 785 |         8'h61:
 786 |             out <= 8'hc5;
 787 |         8'h62:
 788 |             out <= 8'h4f;
 789 |         8'h63:
 790 |             out <= 8'hed;
 791 |         8'h64:
 792 |             out <= 8'h86;
 793 |         8'h65:
 794 |             out <= 8'h9a;
 795 |         8'h66:
 796 |             out <= 8'h66;
 797 |         8'h67:
 798 |             out <= 8'h11;
 799 |         8'h68:
 800 |             out <= 8'h8a;
 801 |         8'h69:
 802 |             out <= 8'he9;
 803 |         8'h6a:
 804 |             out <= 8'h04;
 805 |         8'h6b:
 806 |             out <= 8'hfe;
 807 |         8'h6c:
 808 |             out <= 8'ha0;
 809 |         8'h6d:
 810 |             out <= 8'h78;
 811 |         8'h6e:
 812 |             out <= 8'h25;
 813 |         8'h6f:
 814 |             out <= 8'h4b;
 815 |         8'h70:
 816 |             out <= 8'ha2;
 817 |         8'h71:
 818 |             out <= 8'h5d;
 819 |         8'h72:
 820 |             out <= 8'h80;
 821 |         8'h73:
 822 |             out <= 8'h05;
 823 |         8'h74:
 824 |             out <= 8'h3f;
 825 |         8'h75:
 826 |             out <= 8'h21;
 827 |         8'h76:
 828 |             out <= 8'h70;
 829 |         8'h77:
 830 |             out <= 8'hf1;
 831 |         8'h78:
 832 |             out <= 8'h63;
 833 |         8'h79:
 834 |             out <= 8'h77;
 835 |         8'h7a:
 836 |             out <= 8'haf;
 837 |         8'h7b:
 838 |             out <= 8'h42;
 839 |         8'h7c:
 840 |             out <= 8'h20;
 841 |         8'h7d:
 842 |             out <= 8'he5;
 843 |         8'h7e:
 844 |             out <= 8'hfd;
 845 |         8'h7f:
 846 |             out <= 8'hbf;
 847 |         8'h80:
 848 |             out <= 8'h81;
 849 |         8'h81:
 850 |             out <= 8'h18;
 851 |         8'h82:
 852 |             out <= 8'h26;
 853 |         8'h83:
 854 |             out <= 8'hc3;
 855 |         8'h84:
 856 |             out <= 8'hbe;
 857 |         8'h85:
 858 |             out <= 8'h35;
 859 |         8'h86:
 860 |             out <= 8'h88;
 861 |         8'h87:
 862 |             out <= 8'h2e;
 863 |         8'h88:
 864 |             out <= 8'h93;
 865 |         8'h89:
 866 |             out <= 8'h55;
 867 |         8'h8a:
 868 |             out <= 8'hfc;
 869 |         8'h8b:
 870 |             out <= 8'h7a;
 871 |         8'h8c:
 872 |             out <= 8'hc8;
 873 |         8'h8d:
 874 |             out <= 8'hba;
 875 |         8'h8e:
 876 |             out <= 8'h32;
 877 |         8'h8f:
 878 |             out <= 8'he6;
 879 |         8'h90:
 880 |             out <= 8'hc0;
 881 |         8'h91:
 882 |             out <= 8'h19;
 883 |         8'h92:
 884 |             out <= 8'h9e;
 885 |         8'h93:
 886 |             out <= 8'ha3;
 887 |         8'h94:
 888 |             out <= 8'h44;
 889 |         8'h95:
 890 |             out <= 8'h54;
 891 |         8'h96:
 892 |             out <= 8'h3b;
 893 |         8'h97:
 894 |             out <= 8'h0b;
 895 |         8'h98:
 896 |             out <= 8'h8c;
 897 |         8'h99:
 898 |             out <= 8'hc7;
 899 |         8'h9a:
 900 |             out <= 8'h6b;
 901 |         8'h9b:
 902 |             out <= 8'h28;
 903 |         8'h9c:
 904 |             out <= 8'ha7;
 905 |         8'h9d:
 906 |             out <= 8'hbc;
 907 |         8'h9e:
 908 |             out <= 8'h16;
 909 |         8'h9f:
 910 |             out <= 8'had;
 911 |         8'ha0:
 912 |             out <= 8'hdb;
 913 |         8'ha1:
 914 |             out <= 8'h64;
 915 |         8'ha2:
 916 |             out <= 8'h74;
 917 |         8'ha3:
 918 |             out <= 8'h14;
 919 |         8'ha4:
 920 |             out <= 8'h92;
 921 |         8'ha5:
 922 |             out <= 8'h0c;
 923 |         8'ha6:
 924 |             out <= 8'h48;
 925 |         8'ha7:
 926 |             out <= 8'hb8;
 927 |         8'ha8:
 928 |             out <= 8'h9f;
 929 |         8'ha9:
 930 |             out <= 8'hbd;
 931 |         8'haa:
 932 |             out <= 8'h43;
 933 |         8'hab:
 934 |             out <= 8'hc4;
 935 |         8'hac:
 936 |             out <= 8'h39;
 937 |         8'had:
 938 |             out <= 8'h31;
 939 |         8'hae:
 940 |             out <= 8'hd3;
 941 |         8'haf:
 942 |             out <= 8'hf2;
 943 |         8'hb0:
 944 |             out <= 8'hd5;
 945 |         8'hb1:
 946 |             out <= 8'h8b;
 947 |         8'hb2:
 948 |             out <= 8'h6e;
 949 |         8'hb3:
 950 |             out <= 8'hda;
 951 |         8'hb4:
 952 |             out <= 8'h01;
 953 |         8'hb5:
 954 |             out <= 8'hb1;
 955 |         8'hb6:
 956 |             out <= 8'h9c;
 957 |         8'hb7:
 958 |             out <= 8'h49;
 959 |         8'hb8:
 960 |             out <= 8'hd8;
 961 |         8'hb9:
 962 |             out <= 8'hac;
 963 |         8'hba:
 964 |             out <= 8'hf3;
 965 |         8'hbb:
 966 |             out <= 8'hcf;
 967 |         8'hbc:
 968 |             out <= 8'hca;
 969 |         8'hbd:
 970 |             out <= 8'hf4;
 971 |         8'hbe:
 972 |             out <= 8'h47;
 973 |         8'hbf:
 974 |             out <= 8'h10;
 975 |         8'hc0:
 976 |             out <= 8'h6f;
 977 |         8'hc1:
 978 |             out <= 8'hf0;
 979 |         8'hc2:
 980 |             out <= 8'h4a;
 981 |         8'hc3:
 982 |             out <= 8'h5c;
 983 |         8'hc4:
 984 |             out <= 8'h38;
 985 |         8'hc5:
 986 |             out <= 8'h57;
 987 |         8'hc6:
 988 |             out <= 8'h73;
 989 |         8'hc7:
 990 |             out <= 8'h97;
 991 |         8'hc8:
 992 |             out <= 8'hcb;
 993 |         8'hc9:
 994 |             out <= 8'ha1;
 995 |         8'hca:
 996 |             out <= 8'he8;
 997 |         8'hcb:
 998 |             out <= 8'h3e;
 999 |         8'hcc:
1000 |             out <= 8'h96;
1001 |         8'hcd:
1002 |             out <= 8'h61;
1003 |         8'hce:
1004 |             out <= 8'h0d;
1005 |         8'hcf:
1006 |             out <= 8'h0f;
1007 |         8'hd0:
1008 |             out <= 8'he0;
1009 |         8'hd1:
1010 |             out <= 8'h7c;
1011 |         8'hd2:
1012 |             out <= 8'h71;
1013 |         8'hd3:
1014 |             out <= 8'hcc;
1015 |         8'hd4:
1016 |             out <= 8'h90;
1017 |         8'hd5:
1018 |             out <= 8'h06;
1019 |         8'hd6:
1020 |             out <= 8'hf7;
1021 |         8'hd7:
1022 |             out <= 8'h1c;
1023 |         8'hd8:
1024 |             out <= 8'hc2;
1025 |         8'hd9:
1026 |             out <= 8'h6a;
1027 |         8'hda:
1028 |             out <= 8'hae;
1029 |         8'hdb:
1030 |             out <= 8'h69;
1031 |         8'hdc:
1032 |             out <= 8'h17;
1033 |         8'hdd:
1034 |             out <= 8'h99;
1035 |         8'hde:
1036 |             out <= 8'h3a;
1037 |         8'hdf:
1038 |             out <= 8'h27;
1039 |         8'he0:
1040 |             out <= 8'hd9;
1041 |         8'he1:
1042 |             out <= 8'heb;
1043 |         8'he2:
1044 |             out <= 8'h2b;
1045 |         8'he3:
1046 |             out <= 8'h22;
1047 |         8'he4:
1048 |             out <= 8'hd2;
1049 |         8'he5:
1050 |             out <= 8'ha9;
1051 |         8'he6:
1052 |             out <= 8'h07;
1053 |         8'he7:
1054 |             out <= 8'h33;
1055 |         8'he8:
1056 |             out <= 8'h2d;
1057 |         8'he9:
1058 |             out <= 8'h3c;
1059 |         8'hea:
1060 |             out <= 8'h15;
1061 |         8'heb:
1062 |             out <= 8'hc9;
1063 |         8'hec:
1064 |             out <= 8'h87;
1065 |         8'hed:
1066 |             out <= 8'haa;
1067 |         8'hee:
1068 |             out <= 8'h50;
1069 |         8'hef:
1070 |             out <= 8'ha5;
1071 |         8'hf0:
1072 |             out <= 8'h03;
1073 |         8'hf1:
1074 |             out <= 8'h59;
1075 |         8'hf2:
1076 |             out <= 8'h09;
1077 |         8'hf3:
1078 |             out <= 8'h1a;
1079 |         8'hf4:
1080 |             out <= 8'h65;
1081 |         8'hf5:
1082 |             out <= 8'hd7;
1083 |         8'hf6:
1084 |             out <= 8'h84;
1085 |         8'hf7:
1086 |             out <= 8'hd0;
1087 |         8'hf8:
1088 |             out <= 8'h82;
1089 |         8'hf9:
1090 |             out <= 8'h29;
1091 |         8'hfa:
1092 |             out <= 8'h5a;
1093 |         8'hfb:
1094 |             out <= 8'h1e;
1095 |         8'hfc:
1096 |             out <= 8'h7b;
1097 |         8'hfd:
1098 |             out <= 8'ha8;
1099 |         8'hfe:
1100 |             out <= 8'h6d;
1101 |         8'hff:
1102 |             out <= 8'h2c;
1103 |     endcase
1104 | endmodule
1105 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
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526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 | 
536 |   Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 | 
540 |   12. No Surrender of Others' Freedom.
541 | 
542 |   If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License.  If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all.  For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 | 
552 |   13. Use with the GNU Affero General Public License.
553 | 
554 |   Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work.  The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 | 
563 |   14. Revised Versions of this License.
564 | 
565 |   The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time.  Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 | 
570 |   Each version is given a distinguishing version number.  If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation.  If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 | 
579 |   If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 | 
584 |   Later license versions may give you additional or different
585 | permissions.  However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 | 
589 |   15. Disclaimer of Warranty.
590 | 
591 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 | 
600 |   16. Limitation of Liability.
601 | 
602 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 | 
612 |   17. Interpretation of Sections 15 and 16.
613 | 
614 |   If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 | 
621 |                      END OF TERMS AND CONDITIONS
622 | 
623 |             How to Apply These Terms to Your New Programs
624 | 
625 |   If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 | 
629 |   To do so, attach the following notices to the program.  It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 | 
634 |     <one line to give the program's name and a brief idea of what it does.>
635 |     Copyright (C) <year>  <name of author>
636 | 
637 |     This program is free software: you can redistribute it and/or modify
638 |     it under the terms of the GNU General Public License as published by
639 |     the Free Software Foundation, either version 3 of the License, or
640 |     (at your option) any later version.
641 | 
642 |     This program is distributed in the hope that it will be useful,
643 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
644 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
645 |     GNU General Public License for more details.
646 | 
647 |     You should have received a copy of the GNU General Public License
648 |     along with this program.  If not, see <https://www.gnu.org/licenses/>.
649 | 
650 | Also add information on how to contact you by electronic and paper mail.
651 | 
652 |   If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 | 
655 |     <program>  Copyright (C) <year>  <name of author>
656 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 |     This is free software, and you are welcome to redistribute it
658 |     under certain conditions; type `show c' for details.
659 | 
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License.  Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 | 
664 |   You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | <https://www.gnu.org/licenses/>.
668 | 
669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library.  If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License.  But first, please read
674 | <https://www.gnu.org/licenses/why-not-lgpl.html>.
675 | 


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