Với mục tiêu nghiên cứu đề xuất một số phương pháp MHCTCT có
tính khả thi triển khai trong thực tiễn đảm bảo tính chất đúng đắn, an toàn và
chối từ. Sau một thời gian nghiên cứu và dưới sự hướng dẫn tận tình của tập
thể hướng dẫn khoa học, mặc dù còn nhiều hạn chế về chuyên môn, thời gian
cũng như những khó khăn về nguồn tài liệu, nhất là một lĩnh vực rất hẹp là
lĩnh vực mã hóa có thể chối từ, song nghiên cứu sinh đã nỗ lực hết mình để
hoàn thành các mục tiêu của đề tài Luận án. Có thể tóm lược một số kết quả
chính mà Luận án đã đạt được bao gồm:
A. Kết quả đạt được và đóng góp của Luận án
1- Đề xuất phương pháp tổng quát thực hiện MHCTCT khóa bất đối
xứng dựa trên giao thức ba bước Shamir theo cách thức mã hóa xác suất, sử
dụng các thuật toán mã hóa có tính chất giao hoán. Trên cơ sở phương pháp
tổng quát, đã đề xuất ba giao thức MHCTCT cụ thể sử dụng các hệ mật khác
nhau.
178 trang |
Chia sẻ: tueminh09 | Ngày: 24/01/2022 | Lượt xem: 479 | Lượt tải: 0
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Các kết quả thực nghiệm:
+ Các thuật toán hoạt động đúng đắn, hai bên gửi nhận đảm bảo mã/dịch chính xác thông điệp bí mật và thông điệp giả mạo.
+ Với kích thước tham số như đã chọn, sai khác thời gian tính toán của Thuật toán mã hóa xác suất dựa trên mã khối và thời gian tính toán của
Thuật toán MHCTCT dựa trên mã khối là không phân biệt, thời gian tính toán luôn 310 s.
+ Với kích thước thông điệp đầu vào là 128 bit, thuật toán MHCTCT của Chương 3 dựa trên thuật toán mã khối có tốc độ tính toán nhanh hơn rất
nhiều so với thuật toán MHCTCT của Chương 2 sử dụng mã hóa khóa bất đối xứng.
144
4. Mã nguồn chương trình thực nghiệm Giao thức 2.1
/**
* Algorithm 2.1
*
* Compile: gcc alg_2.1.c -o alg_2.1 -lgmp -lcrypto
*/
#include
#include
#include
#include
#include
#include
#define BITS_IN_BYTE 8
/* Number of bits of prime number */
#define PRIME_BITS 2048
#define Z_BITS 256
#define KZ_BITS 16
#define E_BITS 256
#define CIPHER_KEY_SIZE_BITS 2048
#define MESSAGE_SIZE_BITS 128
#define R_SIZE_BITS 2040
#define MESSAGE_SIZE_BYTES MESSAGE_SIZE_BITS/BITS_IN_BYTE
#define R_SIZE_BYTES R_SIZE_BITS/BITS_IN_BYTE
char buff_to_print[1024];
static char* hex2char(char *dst, unsigned char b);
const char* hex2str(const char *bin, int bin_size, char *buff, int
buff_size);
void generate_primes(mpz_t prime, int len);
void generate_mpz(mpz_t big, int len);
void mpz_to_str(mpz_t big, char *str);
void str_to_mpz(char *str, mpz_t big);
void generate_e_d(mpz_t phi, int len, mpz_t e, mpz_t d);
void get_D(mpz_t big_p,
mpz_t big_z,
mpz_t big_kz,
mpz_t big_D);
void get_DC1(mpz_t big_p,
mpz_t big_z,
mpz_t big_kz,
mpz_t big_r,
mpz_t big_s,
mpz_t big_DC1);
void get_DC2(mpz_t big_p,
mpz_t big_s,
mpz_t big_r,
mpz_t big_DC2);
void get_s(mpz_t big_p,
mpz_t big_c1,
mpz_t big_c2,
mpz_t big_z,
mpz_t big_s1);
void get_u(mpz_t big_p,
mpz_t big_c1,
mpz_t big_c2,
mpz_t big_z,
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mpz_t big_kz,
mpz_t big_s2);
void ProcPH(mpz_t big_p,
mpz_t big_r,
mpz_t big_z,
mpz_t big_kz,
mpz_t big_e,
mpz_t big_m,
mpz_t big_c1,
mpz_t big_c2);
/* CHUONG TRINH CHINH */
int main(int argc, char *argv[]) {
if ((int) argc != 2) {
printf("ERROR: Not enough parameters.\n");
printf(
"Usage: alg_2.1 n");
printf("\nWhere:\n");
printf("\tn: Number of running times\n");
printf("\tExample:./alg_2.1 10\n\n");
return 0;
}
int RUN_TIMES = atoi(argv[1]);
int i, ret;
clock_t time_taken_start, time_taken_end;
double enc_time_taken_prob[RUN_TIMES];
double dec_time_taken_prob[RUN_TIMES];
double enc_time_taken_deni[RUN_TIMES];
double dec_time_taken_deni[RUN_TIMES];
double enc_time_taken_average_prob = 0;
double dec_time_taken_average_prob = 0;
double enc_time_taken_average_deni = 0;
double dec_time_taken_average_deni = 0;
int dec_ok[RUN_TIMES];
int dec_true_ok[RUN_TIMES];
int dec_fake_ok[RUN_TIMES];
unsigned char *m_true_A = malloc(MESSAGE_SIZE_BYTES);
unsigned char *m_true_B = malloc(MESSAGE_SIZE_BYTES);
unsigned char *m_fake_A = malloc(MESSAGE_SIZE_BYTES);
unsigned char *m_fake_B = malloc(MESSAGE_SIZE_BYTES);
unsigned char *r1 = malloc(R_SIZE_BYTES);
unsigned char *r2 = malloc(R_SIZE_BYTES);
unsigned char *r3 = malloc(R_SIZE_BYTES);
mpz_t big_m_true_A; mpz_init(big_m_true_A);
mpz_t big_m_true_B; mpz_init(big_m_true_B);
mpz_t big_m_fake_A; mpz_init(big_m_fake_A);
mpz_t big_m_fake_B; mpz_init(big_m_fake_B);
mpz_t big_z; mpz_init(big_z);
mpz_t big_kz; mpz_init(big_kz);
mpz_t big_p; mpz_init(big_p);
mpz_t big_phi; mpz_init(big_phi);
mpz_t big_eA; mpz_init(big_eA);
mpz_t big_dA; mpz_init(big_dA);
mpz_t big_eB; mpz_init(big_eB);
mpz_t big_dB; mpz_init(big_dB);
146
mpz_t big_EA; mpz_init(big_EA);
mpz_t big_DA; mpz_init(big_DA);
mpz_t big_EB; mpz_init(big_EB);
mpz_t big_DB; mpz_init(big_DB);
mpz_t big_gcd; mpz_init(big_gcd);
mpz_t big_r1; mpz_init(big_r1);
mpz_t big_r2; mpz_init(big_r2);
mpz_t big_r3; mpz_init(big_r3);
mpz_t big_s1; mpz_init(big_s1);
mpz_t big_s2; mpz_init(big_s2);
mpz_t big_s3; mpz_init(big_s3);
mpz_t big_u1; mpz_init(big_u1);
mpz_t big_u2; mpz_init(big_u2);
mpz_t big_u3; mpz_init(big_u3);
mpz_t big_c11; mpz_init(big_c11);
mpz_t big_c12; mpz_init(big_c12);
mpz_t big_c21; mpz_init(big_c21);
mpz_t big_c22; mpz_init(big_c22);
mpz_t big_c31; mpz_init(big_c31);
mpz_t big_c32; mpz_init(big_c32);
/* SINH SO NGUYEN TO p, GIA LAP TAO THAM SO Z, kz */
printf("Generating a prime number [p], please wait...:\n");
generate_primes(big_p, PRIME_BITS);
printf("Generated a prime number [p] with [%d] digits.\n",
PRIME_BITS/8);
gmp_printf ("\t[p] = \t\t%Zd\n", big_p);
/* phi = (p - 1) */
mpz_sub_ui(big_phi, big_p, 1);
gmp_printf ("\t[phi] = \t%Zd\n", big_phi);
/* Generate z */
generate_mpz(big_z, Z_BITS);
gmp_printf ("\t[z] = \t\t%Zd\n", big_z);
/* Generate z, kz */
generate_mpz(big_kz, KZ_BITS);
gmp_printf ("\t[kz] = \t\t%Zd\n", big_kz);
printf("\n[A] and [B] have big prime number [p], [phi] = [p-1],
and keys [z, kz]:\n");
gmp_printf ("\t[p] = \t\t%Zd\n", big_p);
gmp_printf ("\t[phi] = \t%Zd\n", big_phi);
gmp_printf ("\t[z] = \t\t%Zd\n", big_z);
gmp_printf ("\t[kz] = \t\t%Zd\n", big_kz);
for (i = 0; i < RUN_TIMES; i++) {
printf("\n\nEXECUTION: %d...\n", i + 1);
printf("\n[A] have messages [m_true], [m_fake]:\n");
RAND_bytes(m_true_A, MESSAGE_SIZE_BYTES);
RAND_bytes(m_fake_A, MESSAGE_SIZE_BYTES);
printf("\t[m_true_A] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[m_fake_A] = \t%s\n", hex2str((const char*
)m_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
str_to_mpz(m_true_A, big_m_true_A);
str_to_mpz(m_fake_A, big_m_fake_A);
printf("\n[A] generate [eA, dA]:\n");
generate_e_d(big_phi, E_BITS, big_eA, big_dA);
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gmp_printf ("\t[eA] =\t \t%Zd\n", big_eA);
gmp_printf ("\t[dA] = \t\t%Zd\n", big_dA);
mpz_gcd(big_gcd, big_eA, big_phi);
gmp_printf ("\t[gcd(eA, phi)] = %Zd\n", big_gcd);
printf("\n[B] generate [eB, dB]:\n");
generate_e_d(big_phi, E_BITS, big_eB, big_dB);
gmp_printf ("\t[eB] =\t \t%Zd\n", big_eB);
gmp_printf ("\t[dB] = \t\t%Zd\n", big_dB);
mpz_gcd(big_gcd, big_eB, big_phi);
gmp_printf ("\t[gcd(eB, phi)] = %Zd\n", big_gcd);
printf("\n[A] generate [EA, EA]:\n");
generate_e_d(big_phi, E_BITS, big_EA, big_DA);
gmp_printf ("\t[EA] =\t \t%Zd\n", big_EA);
gmp_printf ("\t[DA] = \t\t%Zd\n", big_DA);
mpz_gcd(big_gcd, big_EA, big_phi);
gmp_printf ("\t[gcd(EA, phi)] = %Zd\n", big_gcd);
printf("\n[B] generate [EB, DB]:\n");
generate_e_d(big_phi, E_BITS, big_EB, big_DB);
gmp_printf ("\t[EB] =\t \t%Zd\n", big_EB);
gmp_printf ("\t[DB] = \t\t%Zd\n", big_DB);
mpz_gcd(big_gcd, big_eB, big_phi);
gmp_printf ("\t[gcd(EB, phi)] = %Zd\n", big_gcd);
/* THUAT TOAN CUA GIAO THUC 2.1 HĐ O CHE DO MA HOA XAC SUAT */
printf("\n\nI. ALGORITHM PROBABILITY ENCRYPTION (2.1a)");
printf("\n===================================================\n");
printf("[A] WANT TO SEND A MESSAGE TO [B]!\n");
printf("[A] --> message [m] --> [B]\n\n");
printf("\t[m] = \t\t%s\n", hex2str((const char* )m_fake_A,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
time_taken_start = clock();
printf("\nA.1. [A] generate [r1]:\n");
RAND_bytes(r1, R_SIZE_BYTES);
printf("\t[r1] = \t\t%s\n\n", hex2str((const char* )r1,
R_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
str_to_mpz(r1, big_r1);
printf("\nA.2. [A] compute [c11, c12] from [r1, z, kz, eA,
m]:\n");
ProcPH(big_p, big_r1, big_z, big_kz, big_eA, big_m_fake_A,
big_c11, big_c12);
gmp_printf ("\t[c11] = \t%Zd\n", big_c11);
gmp_printf ("\t[c12] = \t%Zd\n", big_c12);
printf("\nA.3. [A] send [c11, c12] to [B]:\n");
printf("\nSending....\n");
printf("Sending....\n");
printf("Sending....\n");
printf("\nStep 2. [B] receive [c11, c12] from [A], choose
[r2]:\n");
gmp_printf ("\t[c11] = \t%Zd\n", big_c11);
gmp_printf ("\t[c12] = \t%Zd\n", big_c12);
printf("\nB.1. [A] generate [r2]:\n");
148
RAND_bytes(r2, R_SIZE_BYTES);
printf("\t[r2] = \t\t%s\n\n", hex2str((const char* )r2,
R_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
str_to_mpz(r2, big_r2);
printf("\nB.2. [B] compute [s1] from [c11, c12, z]:\n");
get_s(big_p, big_c11, big_c12, big_z, big_s1);
gmp_printf ("\t[s1] = \t\t%Zd\n", big_s1);
printf("\nB.3. [B] compute [c21, c22] from [r2, z, kz, eB,
s1]:\n");
ProcPH(big_p, big_r2, big_z, big_kz, big_eB, big_s1,
big_c21, big_c22);
gmp_printf ("\t[c21] = \t%Zd\n", big_c21);
gmp_printf ("\t[c22] = \t%Zd\n", big_c22);
printf("\nB.4. [B] send [c21, c22] to [A]:\n");
printf("\nSending....\n");
printf("Sending....\n");
printf("Sending....\n");
printf("\nStep 3. [A] receive [c11, c12] from [B]:\n");
gmp_printf ("\t[c21] = \t%Zd\n", big_c21);
gmp_printf ("\t[c22] = \t%Zd\n", big_c22);
printf("\n\nA.4. [A] generate [r3]:\n");
RAND_bytes(r3, R_SIZE_BYTES);
printf("\t[r3] = \t\t%s\n\n", hex2str((const char* )r3,
R_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
str_to_mpz(r3, big_r3);
printf("\nA.5. [A] compute [s2] from [c21, c22, z]:\n");
get_s(big_p, big_c21, big_c22, big_z, big_s2);
gmp_printf ("\t[s2] = \t\t%Zd\n", big_s2);
printf("\nA.6. [A] compute [c31, c32] from [r3, z, kz, dA,
s2]:\n");
ProcPH(big_p, big_r3, big_z, big_kz, big_dA, big_s2,
big_c31, big_c32);
gmp_printf ("\t[c31] = \t%Zd\n", big_c31);
gmp_printf ("\t[c32] = \t%Zd\n", big_c32);
time_taken_end = clock();
enc_time_taken_prob[i] = (((double) (time_taken_end -
time_taken_start)) / CLOCKS_PER_SEC) * 1000;
printf("\nA.7. [A] send [c31, c32] to [B]:\n");
printf("\nSending....\n");
printf("Sending....\n");
printf("Sending....\n");
printf("\nDecryption. [B] receive [c31, c32] from [A]:\n");
gmp_printf ("\t[c31] = \t%Zd\n", big_c31);
gmp_printf ("\t[c32] = \t%Zd\n", big_c32);
time_taken_start = clock();
printf("\nB.5. [B] compute [s3] from [c31, c32, z]:\n");
get_s(big_p, big_c31, big_c32, big_z, big_s3);
gmp_printf ("\t[s3] = \t\t%Zd\n", big_s3);
printf("\nB.6. [B] compute [m] from [s3, dB]:\n");
mpz_powm(big_m_fake_B, big_s3, big_dB, big_p);
mpz_to_str(big_m_fake_B, m_fake_B);
printf("\t[m] = \t\t%s\n", hex2str((const char* )m_fake_B,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
149
printf("\nB.7. [B] compare with [m] from [A]:\n");
printf("\t[m] = \t\t%s\n", hex2str((const char* )m_fake_A,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
time_taken_end = clock();
dec_time_taken_prob[i] = (((double) (time_taken_end -
time_taken_start)) / CLOCKS_PER_SEC) * 1000;
if(memcmp(m_fake_B, m_fake_A, MESSAGE_SIZE_BYTES) == 0) {
printf("\nOK, [A] HAVE SUCCESSFULY SENT A MESSAGE [m]
TO [B]!\n");
dec_ok[i] = 1;
} else {
printf("\nWOW, THEY ARE NOT THE SAME (SOMETHING WENT
WRONG!!!)\n");
dec_ok[i] = 0;
}
/* THUAT TOAN CUA GIAO THUC 2.1 HĐ O CHE DO GAI DAT MHCTCT */
printf("\n\nII. ALGORITHM DENIABLE ENCRYPTION (2.1b)");
printf("\n===================================================\n");
printf("[A] WANT TO SEND A MESSAGES TO [B]!\n");
printf("[A] --> message [m_true, m_fake] --> [B]\n");
printf("\t[m_fake] = \t%s\n", hex2str((const char*
)m_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[m_true] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
time_taken_start = clock();
printf("\nA.1. [A] compute [r1] from [m_true]:\n");
mpz_powm(big_r1, big_m_true_A, big_EA, big_p);
gmp_printf ("\t[r1] = \t\t%Zd\n", big_r1);
printf("\nA.2. [A] compute [c11, c12] from [r1, z, kz, eA,
m_fake]:\n");
ProcPH(big_p, big_r1, big_z, big_kz, big_eA, big_m_fake_A,
big_c11, big_c12);
gmp_printf ("\t[c11] = \t%Zd\n", big_c11);
gmp_printf ("\t[c12] = \t%Zd\n", big_c12);
printf("\nA.3. [A] send [c11, c12] to [B]:\n");
printf("\nSending....\n");
printf("Sending....\n");
printf("Sending....\n");
printf("\nStep 2. [B] receive [c11, c12] from [A]:\n");
gmp_printf ("\t[c11] = \t%Zd\n", big_c11);
gmp_printf ("\t[c12] = \t%Zd\n", big_c12);
printf("\nB.1. [B] compute [u1] from [c11, c12, z, kz]:\n");
get_u(big_p, big_c11, big_c12, big_z, big_kz, big_u1);
gmp_printf ("\t[u1] = \t\t%Zd\n", big_u1);
printf("\nB.2. [B] compute [r2] from [u1, EB]:\n");
mpz_powm(big_r2, big_u1, big_EB, big_p);
gmp_printf ("\t[r2] = \t\t%Zd\n", big_r2);
printf("\nB.3. [B] compute [s1] from [c11, c12, z]:\n");
get_s(big_p, big_c11, big_c12, big_z, big_s1);
gmp_printf ("\t[s1] = \t\t%Zd\n", big_s1);
150
printf("\nB.4. [B] compute [c21, c22] from [r2, z, kz, eB,
s1]:\n");
ProcPH(big_p, big_r2, big_z, big_kz, big_eB, big_s1,
big_c21, big_c22);
gmp_printf ("\t[c21] = \t%Zd\n", big_c21);
gmp_printf ("\t[c22] = \t%Zd\n", big_c22);
printf("\nB.5. [B] send [c21, c22] to [A]:\n");
printf("\nSending....\n");
printf("Sending....\n");
printf("Sending....\n");
printf("\nStep 3. [A] receive [c21, c22] from [B]:\n");
gmp_printf ("\t[c21] = \t%Zd\n", big_c21);
gmp_printf ("\t[c22] = \t%Zd\n", big_c22);
printf("\nA.4. [A] compute [u2] from [c21, c22, kz, z]:\n");
get_u(big_p, big_c21, big_c22, big_z, big_kz, big_u2);
gmp_printf ("\t[u2] = \t\t%Zd\n", big_u2);
printf("\nA.5. [A] compute [r3] from [u2, DA]:\n");
mpz_powm(big_r3, big_u2, big_DA, big_p);
gmp_printf ("\t[r3] = \t\t%Zd\n", big_r3);
printf("\nA.6. [A] compute [s2] from [c21, c22, z]:\n");
get_s(big_p, big_c21, big_c22, big_z, big_s2);
gmp_printf ("\t[s2] = \t\t%Zd\n", big_s2);
printf("\nA.7. [A] compute [c31, c32] from [r3, z, kz, dA,
s2]:\n");
ProcPH(big_p, big_r3, big_z, big_kz, big_dA, big_s2,
big_c31, big_c32);
gmp_printf ("\t[c31] = \t%Zd\n", big_c31);
gmp_printf ("\t[c32] = \t%Zd\n", big_c32);
time_taken_end = clock();
enc_time_taken_deni[i] = (((double) (time_taken_end -
time_taken_start)) / CLOCKS_PER_SEC) * 1000;
printf("\nA.8. [A] send [c31, c32] to [B]:\n");
printf("\nSending....\n");
printf("Sending....\n");
printf("Sending....\n");
printf("\nDecryption. [B] receive [c31, c32] from [A]:\n");
gmp_printf ("\t[c31] = \t%Zd\n", big_c31);
gmp_printf ("\t[c32] = \t%Zd\n", big_c32);
time_taken_start = clock();
printf("\nB.6. [B] compute [u3] from [c31, c32, z, kz]:\n");
get_u(big_p, big_c31, big_c32, big_z, big_kz, big_u3);
gmp_printf ("\t[u3] = \t\t%Zd\n", big_u3);
printf("\nB.7. [B] compute [s3] from [c31, c32, z]:\n");
get_s(big_p, big_c31, big_c32, big_z, big_s3);
gmp_printf ("\t[s3] = \t\t%Zd\n", big_s3);
printf("\nIn ATTACKED condition!!!\n");
printf("B.8. [B] compute [m_fake] from [s3, dB]:\n");
mpz_powm(big_m_fake_B, big_s3, big_dB, big_p);
mpz_to_str(big_m_fake_B, m_fake_B);
printf("\t[m_fake] = \t%s\n", hex2str((const char*
)m_fake_B, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n[B] compare with [m_fake] from [A]:\n");
printf("\t[m_fake] = \t%s\n", hex2str((const char*
)m_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
151
if(memcmp(m_fake_B, m_fake_A, MESSAGE_SIZE_BYTES) == 0) {
printf("\nOK, [A] HAVE SUCCESSFULY SENT A MESSAGE
[m_fake] TO [B]!\n");
dec_fake_ok[i] = 1;
} else {
printf("\nWOW, THEY ARE NOT THE SAME (SOMETHING WENT
WRONG!!!)\n");
dec_fake_ok[i] = 0;
}
printf("\nIn NORMAL condition:\n");
printf("B.10. [B] compute [m_true] from [u3, DB]:\n");
mpz_powm(big_m_true_B, big_u3, big_DB, big_p);
mpz_to_str(big_m_true_B, m_true_B);
printf("\t[m_true] = \t%s\n", hex2str((const char*
)m_true_B, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
time_taken_end = clock();
dec_time_taken_deni[i] = (((double) (time_taken_end -
time_taken_start)) / CLOCKS_PER_SEC) * 1000;
printf("\n[B] compare with [m_true] from [A]:\n");
printf("\t[m_true] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
if(memcmp(m_true_B, m_true_A, MESSAGE_SIZE_BYTES) == 0) {
printf("\nOK, [A] HAVE SUCCESSFULY SENT A MESSAGE
[m_fake] TO [B]!\n");
dec_true_ok[i] = 1;
} else {
printf("\nWOW, THEY ARE NOT THE SAME (SOMETHING WENT
WRONG!!!)\n");
dec_true_ok[i] = 0;
}
printf("\nEXECUTION: %d... DONE\n", i + 1);
printf("\n***************************************************\n");
enc_time_taken_average_prob = enc_time_taken_average_prob +
enc_time_taken_prob[i];
dec_time_taken_average_prob = dec_time_taken_average_prob +
dec_time_taken_prob[i];
enc_time_taken_average_deni = enc_time_taken_average_deni +
enc_time_taken_deni[i];
dec_time_taken_average_deni = dec_time_taken_average_deni +
dec_time_taken_deni[i];
/* Pause 1 seconds */
sleep(1);
}
enc_time_taken_average_prob =
enc_time_taken_average_prob/RUN_TIMES;
dec_time_taken_average_prob =
dec_time_taken_average_prob/RUN_TIMES;
152
enc_time_taken_average_deni =
enc_time_taken_average_deni/RUN_TIMES;
dec_time_taken_average_deni =
dec_time_taken_average_deni/RUN_TIMES;
printf("\n\n\t\t\t\tALG. 2.1 EXECUTION TIME TAKEN AVERAGE\n");
printf("\t\t\t\t Number of running times: %d\n", RUN_TIMES);
printf("\n\tNo/Time(ms) \tEnc_prob \tDec_prob \tEnc_deni
\tDec_deni\tSUCCESSFULY");
printf("\n--------------------------------------------------\n");
char *dec_char, *dec_true_char, *dec_fake_char;
for (i = 0; i < RUN_TIMES; i++) {
if (dec_ok[i]) {
dec_char = "yes";
} else {
dec_char = " no";
}
if (dec_true_ok[i]) {
dec_true_char = "yes";
} else {
dec_true_char = " no";
}
if (dec_fake_ok[i]) {
dec_fake_char = "yes";
} else {
dec_fake_char = " no";
}
printf(" \t %d \t\t%f \t%f \t%f \t%f\t%s, %s, %s\n", i + 1,
enc_time_taken_prob[i], dec_time_taken_prob[i],
enc_time_taken_deni[i], dec_time_taken_deni[i],
dec_char, dec_true_char, dec_fake_char);
}
printf("\n-------------------------------------------------\n");
printf("Average (miliseconds) \t%f \t%f \t%f \t%f\n\n",
enc_time_taken_average_prob,
dec_time_taken_average_prob,
enc_time_taken_average_deni,
dec_time_taken_average_deni);
mpz_clear(big_p);
mpz_clear(big_phi);
mpz_clear(big_z);
mpz_clear(big_kz);
mpz_clear(big_eA);
mpz_clear(big_dA);
mpz_clear(big_eB);
mpz_clear(big_dB);
mpz_clear(big_EA);
mpz_clear(big_DA);
mpz_clear(big_EB);
mpz_clear(big_DB);
mpz_clear(big_gcd);
mpz_clear(big_r1);
mpz_clear(big_r2);
153
mpz_clear(big_r3);
mpz_clear(big_s1);
mpz_clear(big_s2);
mpz_clear(big_s3);
mpz_clear(big_u1);
mpz_clear(big_u2);
mpz_clear(big_u3);
mpz_clear(big_m_true_A);
mpz_clear(big_m_true_B);
mpz_clear(big_m_fake_A);
mpz_clear(big_m_fake_B);
mpz_clear(big_c11);
mpz_clear(big_c12);
mpz_clear(big_c21);
mpz_clear(big_c22);
mpz_clear(big_c31);
mpz_clear(big_c32);
return 1;
}
/* CAC HAM, THU TUC DUNG TRONG CHUONG TRINH CHINH */
/* HAM TINH DINH THUC: D = (z - z * kz)-1 mod p */
void get_D(mpz_t big_p,
mpz_t big_z,
mpz_t big_kz,
mpz_t big_D) {
mpz_t big_tmp1; mpz_init(big_tmp1);
mpz_t big_tmp2; mpz_init(big_tmp2);
mpz_t big_tmp3; mpz_init(big_tmp3);
/* big_tmp1 = (z * kz) */
mpz_mul(big_tmp1, big_z, big_kz);
/* big_tmp2 = (z - (z * kz)) = z - big_tmp1 */
mpz_sub(big_tmp2, big_z, big_tmp1);
/* big_tmp3 = ((z - (kz * z))^-1 mod p) = big_tmp2^-1 mod p */
mpz_invert(big_tmp3, big_tmp2, big_p);
/* Copy big_tmp3 to big_D */
mpz_set(big_D, big_tmp3);
mpz_clear(big_tmp1);
mpz_clear(big_tmp2);
mpz_clear(big_tmp3);
return;
}
/* HAM TINH DINH THUC: DC’ = (z - (kz * z *s)) mod p */
void get_DC1(mpz_t big_p,
mpz_t big_z,
mpz_t big_kz,
mpz_t big_r,
mpz_t big_s,
mpz_t big_DC1) {
154
mpz_t big_tmp1; mpz_init(big_tmp1);
mpz_t big_tmp2; mpz_init(big_tmp2);
mpz_t big_tmp3; mpz_init(big_tmp3);
mpz_t big_tmp4; mpz_init(big_tmp4);
/* big_tmp1 = (z * kz) */
mpz_mul(big_tmp1, big_kz, big_z);
/* big_tmp2 = (kz * z * s) */
mpz_mul(big_tmp2, big_tmp1, big_s);
/* big_tmp3 = (z * r) */
mpz_mul(big_tmp3, big_z, big_r);
/* big_tmp4 = ((z * r) - (kz * z *s)) = big_tmp3 - big_tmp2 */
mpz_sub(big_tmp4, big_tmp3, big_tmp2);
/* big_DC1 = (((z * r) - (kz * z *s)) mod p) = big_tmp4 mod p */
mpz_mod(big_DC1, big_tmp4, big_p);
mpz_clear(big_tmp1);
mpz_clear(big_tmp2);
mpz_clear(big_tmp3);
mpz_clear(big_tmp4);
return;
}
/* HAM TINH DINH THUC: DC” = (s - r) mod p */
void get_DC2(mpz_t big_p,
mpz_t big_s,
mpz_t big_r,
mpz_t big_DC2) {
mpz_t big_tmp1; mpz_init(big_tmp1);
/* big_tmp1 = (s - r) */
mpz_sub(big_tmp1, big_s, big_r);
/* big_DC2 = (s - r) mod p */
mpz_mod(big_DC2, big_tmp1, big_p);
mpz_clear(big_tmp1);
return;
}
/* HAM TINH CAC GIA TRI si: si = (c’i + (z * c”i)) mod p */
void get_s(mpz_t big_p,
mpz_t big_c1,
mpz_t big_c2,
mpz_t big_z,
mpz_t big_s1) {
mpz_t big_tmp1; mpz_init(big_tmp1);
mpz_t big_tmp2; mpz_init(big_tmp2);
/* big_tmp1 = (z * c2) */
mpz_mul(big_tmp1, big_z, big_c2);
/* big_tmp2 = c1 + big_tmp1 */
mpz_add(big_tmp2, big_c1, big_tmp1);
155
/* big_s1 = big_tmp2 mod p */
mpz_mod(big_s1, big_tmp2, big_p);
mpz_clear(big_tmp1);
mpz_clear(big_tmp2);
return;
}
/* HAM TINH CAC GIA TRI ui = (c’i + (kz *z * c”i)) mod p */
void get_u(mpz_t big_p,
mpz_t big_c1,
mpz_t big_c2,
mpz_t big_z,
mpz_t big_kz,
mpz_t big_s2) {
mpz_t big_tmp1; mpz_init(big_tmp1);
mpz_t big_tmp2; mpz_init(big_tmp2);
mpz_t big_tmp3; mpz_init(big_tmp3);
/* big_tmp1 = (z * c2) */
mpz_mul(big_tmp1, big_z, big_c2);
/* big_tmp2 = (kz * z * c2) */
mpz_mul(big_tmp2, big_kz, big_tmp1);
/* big_tmp3 = (c1 + (kz * z * c2)) = c1 + big_tmp2 */
mpz_add(big_tmp3, big_c1, big_tmp2);
/* big_s2 = big_tmp3 mod p */
mpz_mod(big_s2, big_tmp3, big_p);
mpz_clear(big_tmp1);
mpz_clear(big_tmp2);
mpz_clear(big_tmp3);
return;
}
/* HAM KIEM TRA m CO LA PHAN TU NGUYEN THUY CUA Zp* */
void test_m(mmpz_t big_m,
mpz_t big_p,
mpz_t big_p1,
mpz_t test_value) {
mpz_t big_tmp1;
mpz_init(big_tmp2);
mpz_mul(big_tmp1, big_m, big_m);
mpz_mod(big_tmp1, big_tmp1, big_p);
mpz_powm(big_tmp2, big_m, big_p1, big_p);
if(big_tmp1 != 1) && (big_tmp2 != 1) {
test_value = 1;
} else {
test_value = 0;
}
mpz_clear(big_tmp1);
mpz_clear(big_tmp2);
return;
}
/* HAM GIAI HE PHUONG TRINH DONG DU */
void ProcPH(mpz_t big_p,
mpz_t big_r,
mpz_t big_z,
156
mpz_t big_kz,
mpz_t big_e,
mpz_t big_m,
mpz_t big_c1,
mpz_t big_c2) {
int ret = 0;
mpz_t big_s; mpz_init(big_s);
mpz_t big_r; mpz_init(big_r);
mpz_t big_D; mpz_init(big_D);
mpz_t big_DC1; mpz_init(big_DC1);
mpz_t big_DC2; mpz_init(big_DC2);
mpz_t big_tmp1; mpz_init(big_tmp1);
mpz_t big_tmp2; mpz_init(big_tmp2);
/* s = m^e mod p */
mpz_powm(big_s, big_m, big_e, big_p);
/* D = (z - (kz * z))^-1 mod p */
get_D(big_p, big_z, big_kz, big_D);
/* DC1 = (z*r - (z * kz *s)) mod p */
get_DC1(big_p, big_z, big_kz, big_r, big_s, big_DC1);
/* DC2 = (z - r) mod p */
get_DC2(big_p, big_s, big_r, big_DC2);
/* big_c1 = (D * DC1) mod p */
mpz_mul(big_tmp1, big_D, big_DC1);
mpz_mod(big_c1, big_tmp1, big_p);
/* big_c2 = (D * DC2) */
mpz_mul(big_tmp2, big_D, big_DC2);
mpz_mod(big_c2, big_tmp2, big_p);
mpz_clear(big_r);
mpz_clear(big_s);
mpz_clear(big_D);
mpz_clear(big_DC1);
mpz_clear(big_DC2);
mpz_clear(big_tmp1);
mpz_clear(big_tmp2);
return;
}
static char* hex2char(char *dst, unsigned char b) {
unsigned char v = b >> 4;
*dst++ = (v <= 9) ? '0' + v : 'a' + (v - 10);
v = b & 0x0f;
*dst++ = (v <= 9) ? '0' + v : 'a' + (v - 10);
return dst;
}
const char* hex2str(const char *bin, int bin_size, char *buff, int
buff_size) {
char *nptr = buff;
if (NULL == buff) {
return "Buffer is NULL";
}
if (buff_size < bin_size * 2) {
return "Buffer too small";
}
157
while (bin_size--) {
nptr = hex2char(nptr, *bin++);
}
if (buff_size >= bin_size * 2 + 1) {
*nptr = 0;
}
return buff;
}
/*THU TUC SINH SO NGUYEN TO p */
void generate_primes(mpz_t prime, int len) {
int primetest;
mpz_t seed;
mpz_init(seed);
unsigned char *str = malloc(len + len/2);
RAND_bytes(str, len);
mpz_import(seed, len/8, 1, sizeof (str[0]), 0, 0, str);
primetest = mpz_probab_prime_p(seed, 10);
if (primetest != 0) {
mpz_set(prime, seed);
} else {
mpz_nextprime(prime, seed);
}
free(str);
mpz_clear(seed);
return;
}
/*THU TUC TAO KHOA CAC RIENG (e,d) */
void generate_mpz(mpz_t big, int len) {
unsigned char *str = malloc(len);
RAND_bytes(str, len);
mpz_import(big, len/8, 1, sizeof (str[0]), 0, 0, str);
free(str);
return;
}
void generate_e_d(mpz_t phi, int len, mpz_t e, mpz_t d) {
mpz_t seed; mpz_init(seed);
mpz_t temp; mpz_init(temp);
unsigned char *str = malloc(len);
do {
RAND_bytes(str, len);
mpz_import(seed, len/8, 1, sizeof (str[0]), 0, 0, str);
mpz_gcd(temp, phi, seed);
} while (mpz_cmp_ui(temp, 1) != 0);
mpz_set(e, seed);
mpz_invert(d, e, phi);
free(str);
mpz_clear(seed);
mpz_clear(temp);
return;
}
void str_to_mpz(char *str, mpz_t big){
158
mpz_import(big, strlen(str), 1, sizeof (str[0]), 0, 0, str);
return;
}
void mpz_to_str(mpz_t big, char *str){
mpz_export(str, (size_t*) malloc(sizeof (size_t)), 1, sizeof
(str[0]), 0, 0, big);
return;
}
5. Mã nguồn chương trình thực nghiệm Thuật toán 3.1
/**
* Algorithm 3.1
*
* Compile: gcc aes.c alg_3.1.c -o alg_3.1 -lgmp -lcrypto
*/
#include
#include
#include
#include
#include
#include
#include "aes.h"
#define BITS_IN_BYTE 8
/* KHAI BAO THAM SO */
/* Number of bits of prime number */
#define PRIME_BITS 136
#define INTERGER_BITS PRIME_BITS
/* This is for block cipher
* You can change it that suitable for another cipher
* */
#define CIPHER_KEY_SIZE_BITS 256
#define MESSAGE_SIZE_BITS 128
#define CIPHER_KEY_SIZE_BYTES CIPHER_KEY_SIZE_BITS/BITS_IN_BYTE
#define MESSAGE_SIZE_BYTES MESSAGE_SIZE_BITS/BITS_IN_BYTE
char buff_to_print[1024];
static char* hex2char(char *dst, unsigned char b);
const char* hex2str(const char *bin, int bin_size, char *buff, int
buff_size);
void generate_primes(mpz_t prime, int len);
void generate_mpz(mpz_t big, int len);
void mpz_to_str(mpz_t big, char *str);
void str_to_mpz(char *str, mpz_t big);
/* THU TUC MA CUA MA KHOI out = E(in, key) */
void cipher_encrypt(unsigned char in[MESSAGE_SIZE_BYTES],
unsigned char key[CIPHER_KEY_SIZE_BYTES],
unsigned char out[MESSAGE_SIZE_BYTES]) {
unsigned char *key_ctx;
key_ctx = aes_init(CIPHER_KEY_SIZE_BYTES);
aes_key_expansion(key, key_ctx);
aes_encrypt(in, out, key_ctx);
159
free (key_ctx);
return;
}
/* THU TUC DICH CUA MA KHOI out = E(in, key) */
void cipher_decrypt(unsigned char in[MESSAGE_SIZE_BYTES],
unsigned char key[CIPHER_KEY_SIZE_BYTES],
unsigned char out[MESSAGE_SIZE_BYTES]) {
unsigned char *key_ctx;
key_ctx = aes_init(CIPHER_KEY_SIZE_BYTES);
aes_key_expansion(key, key_ctx);
aes_decrypt(in, out, key_ctx);
free (key_ctx);
return;
}
/* THU TUC TINH BAN MA c DUA VAO HE PT DONG DU */
/* Compute c from (cm, k1, k2, r) */
void compute_c(mpz_t big_c, mpz_t big_cm1, mpz_t big_cm2, mpz_t big_k1,
mpz_t big_k2) {
mpz_t big_temp1; mpz_init(big_temp1);
mpz_t big_temp2; mpz_init(big_temp2);
mpz_t big_temp3; mpz_init(big_temp3);
mpz_t big_temp4; mpz_init(big_temp4);
mpz_t big_temp5; mpz_init(big_temp5);
mpz_t big_temp6; mpz_init(big_temp6);
mpz_t big_temp7; mpz_init(big_temp7);
mpz_t big_temp8; mpz_init(big_temp8);
/* big_temp1 = k2^-1 mod k1 */
mpz_invert(big_temp1, big_k2, big_k1);
/* big_temp2 = k2.big_temp1 */
mpz_mul(big_temp2, big_k2, big_temp1);
/* big_temp3 = cm1.big_temp2 */
mpz_mul(big_temp3, big_cm1, big_temp2);
/* big_temp4 = k1^-1 mod k2 */
mpz_invert(big_temp4, big_k1, big_k2);
/* big_temp5 = k1.big_temp4 */
mpz_mul(big_temp5, big_k1, big_temp4);
/* big_temp6 = cm2.big_temp5 */
mpz_mul(big_temp6, big_cm2, big_temp5);
/* big_temp7 = k1.k2 */
mpz_mul(big_temp7, big_k1, big_k1);
/* big_temp8 = big_temp3 + big_temp6 */
mpz_add(big_temp8, big_temp3, big_temp6);
/* c = big_temp8 mod big_temp7 */
mpz_mod(big_c, big_temp8, big_temp7);
mpz_clear(big_temp1);
mpz_clear(big_temp2);
mpz_clear(big_temp3);
mpz_clear(big_temp4);
mpz_clear(big_temp5);
mpz_clear(big_temp6);
mpz_clear(big_temp7);
mpz_clear(big_temp8);
160
return;
}
/* THU TUC TINH cm TU BAN MA c: cm=c mod k1 */
/* Compute cm from (c, k) */
void compute_cm_value(mpz_t big_cm, mpz_t big_c, mpz_t big_k) {
mpz_mod(big_cm, big_c, big_k);
return;
}
/* CHUONG TRINH CHINH */
int main(int argc, char *argv[]) {
if ((int) argc != 2) {
printf("ERROR: Not enough parameters.\n");
printf(
"Usage: alg_3.1 n");
printf("\nWhere:\n");
printf("\tn: Number of running times\n");
printf("\tExample:./alg_3.1 10\n\n");
return 0;
}
int RUN_TIMES = atoi(argv[1]);
int i, ret;
clock_t start, end;
double enc_time_taken[RUN_TIMES];
double dec_time_taken[RUN_TIMES];
double enc_true_fake_time_taken[RUN_TIMES];
double dec_true_time_taken[RUN_TIMES];
double dec_fake_time_taken[RUN_TIMES];
int dec_ok[RUN_TIMES];
int dec_true_ok[RUN_TIMES];
int dec_fake_ok[RUN_TIMES];
double enc_time_taken_average = 0;
double dec_time_taken_average = 0;
double enc_true_fake_time_average = 0;
double dec_true_time_taken_average = 0;
double dec_fake_time_taken_average = 0;
unsigned char *K1 = malloc(CIPHER_KEY_SIZE_BYTES);
unsigned char *K2 = malloc(CIPHER_KEY_SIZE_BYTES);
unsigned char *m_true_A = malloc(MESSAGE_SIZE_BYTES);
unsigned char *m_true_B = malloc(MESSAGE_SIZE_BYTES);
unsigned char *m_fake_A = malloc(MESSAGE_SIZE_BYTES);
unsigned char *m_fake_B = malloc(MESSAGE_SIZE_BYTES);
unsigned char *r = malloc(MESSAGE_SIZE_BYTES);
unsigned char *cm_true_A = malloc(MESSAGE_SIZE_BYTES);
unsigned char *cm_true_B = malloc(MESSAGE_SIZE_BYTES);
unsigned char *cm_fake_A = malloc(MESSAGE_SIZE_BYTES);
unsigned char *cm_fake_B = malloc(MESSAGE_SIZE_BYTES);
mpz_t big_k1; mpz_init(big_k1);
mpz_t big_k2; mpz_init(big_k2);
mpz_t big_gcd; mpz_init(big_gcd);
mpz_t big_r; mpz_init(big_r);
mpz_t big_c; mpz_init(big_c);
mpz_t big_cm_true_A; mpz_init(big_cm_true_A);
mpz_t big_cm_true_B; mpz_init(big_cm_true_B);
161
mpz_t big_cm_fake_A; mpz_init(big_cm_fake_A);
mpz_t big_cm_fake_B; mpz_init(big_cm_fake_B);
for (i = 0; i < RUN_TIMES; i++) {
printf("\nEXECUTION: %d...\n", i + 1);
printf("[A] have messages [m_true], [m_fake]:\n");
RAND_bytes(m_true_A, MESSAGE_SIZE_BYTES);
RAND_bytes(m_fake_A, MESSAGE_SIZE_BYTES);
RAND_bytes(r, MESSAGE_SIZE_BYTES);
printf("\t[m_true_A] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[m_fake_A] = \t%s\n", hex2str((const char*
)m_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[r_A] = \t%s\n\n", hex2str((const char* )r,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
str_to_mpz(r, big_r);
printf("\n[A] and [B] have keys [K1], [K2], [k1], [k2]:\n");
RAND_bytes(K1, CIPHER_KEY_SIZE_BYTES);
RAND_bytes(K2, CIPHER_KEY_SIZE_BYTES);
printf("\t[K1] = \t\t%s\n", hex2str((const char* )K1,
CIPHER_KEY_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[K2] = \t\t%s\n\n", hex2str((const char* )K2,
CIPHER_KEY_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
generate_mpz(big_k1, INTERGER_BITS);
generate_primes(big_k2, PRIME_BITS);
gmp_printf ("\t[k1] = \t\t%Zd\n", big_k1);
gmp_printf ("\t[k2] = \t\t%Zd\n", big_k2);
mpz_gcd(big_gcd, big_k1, big_k2);
gmp_printf ("\t[gcd(k1, k2)] = %Zd\n", big_gcd);
/* THUAT TOAN MA HOA XAC SUAT DUA TREN MA KHOI */
printf("\n\nI. ALGORITHM ENC-DENI AND DEC-DENI (3.1)");
printf("\n==================================================\n");
printf("[A] WANT TO SEND A MESSAGE TO [B]\n");
printf("[A] have [m, r, K1, k1, k2]:\n");
printf("\t[m] = \t\t%s\n", hex2str((const char* )m_fake_A,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[r] = \t\t%s\n", hex2str((const char* )r,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[K1] = \t\t%s\n", hex2str((const char* )K1,
CIPHER_KEY_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
gmp_printf ("\t[k1] = \t\t%Zd\n", big_k1);
gmp_printf ("\t[k2] = \t\t%Zd\n", big_k2);
start = clock();
printf("\n1. [A] encrypt message [m] with key [K1], cm =
E(m, K1):\n");
cipher_encrypt(m_fake_A, K1, cm_fake_A);
printf("\t[cm] = \t\t%s\n", hex2str((const char* )cm_fake_A,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n2. [A] calculate [c] from [cm, k1, k2, r]:\n");
162
str_to_mpz(cm_fake_A, big_cm_fake_A);
compute_c(big_c, big_cm_fake_A, big_r, big_k1, big_k2);
gmp_printf ("\t[c] = \t\t%Zd\n", big_c);
end = clock();
enc_time_taken[i] = (((double) (end - start)) /
CLOCKS_PER_SEC) * 1000;
printf("\n3. [A] send [c] to [B]...\n");
printf("\n...");
printf("\n...");
printf("\n...");
printf("\n\n[B] receive [c] from [A]: \n");
gmp_printf ("\t[c] = \t\t%Zd\n", big_c);
start = clock();
printf("\n1. [B] calculate [cm] from [c] and [k1]:\n");
compute_cm_value(big_cm_fake_B, big_c, big_k1);
mpz_to_str(big_cm_fake_B, cm_fake_B);
printf("\t[cm] = \t\t%s\n", hex2str((const char* )cm_fake_B,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n2. [B] decrypt [cm] with key [K1], m = D(cm,
K1):\n");
cipher_decrypt(cm_fake_B, K1, m_fake_B);
printf("\t[m] = \t\t%s\n", hex2str((const char* )m_fake_B,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
end = clock();
dec_time_taken[i] = (((double) (end - start)) /
CLOCKS_PER_SEC) * 1000;
printf("\n3. [B] compare with [m] that sent from [A]\n");
printf("\t[m] = \t\t%s\n", hex2str((const char* )m_fake_A,
MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
if(memcmp(m_fake_B, m_fake_A, MESSAGE_SIZE_BYTES) == 0) {
printf("\nOK, [A] HAVE SUCCESSFULY SENT A MESSAGE [m]
TO [B]!\n");
dec_ok[i] = 1;
} else {
printf("\nWOW, THEY ARE NOT THE SAME (SOMETHING WENT
WRONG!!!)\n");
dec_ok[i] = 0;
}
/* THUAT TOAN MA HOA CO THE CHOI TU DUA TREN MA KHOI */
printf("\n\nII. ALGORITHM ENC-SEC AND DEC-SEC (3.1)");
printf("\n==================================================\n");
printf("[A] WANT TO SEND MESSAGES TO [B]!\n");
printf("[A] --> Fake message [m_fake] and true message
[m_true] --> [B]\n");
163
printf("[A] have [m_fake, m_true, K1, K2, k1, k2]:\n");
printf("\t[m_true_A] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[m_fake_A] = \t%s\n", hex2str((const char*
)m_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[K1] = \t\t%s\n", hex2str((const char* )K1,
CIPHER_KEY_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\t[K2] = \t\t%s\n", hex2str((const char* )K2,
CIPHER_KEY_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
gmp_printf ("\t[k1] = \t\t%Zd\n", big_k1);
gmp_printf ("\t[k2] = \t\t%Zd\n", big_k2);
start = clock();
printf("\n1. [A] encrypt message [m_fake] with key [K1],
cm_fake = E(m_fake, K1):\n");
cipher_encrypt(m_fake_A, K1, cm_fake_A);
printf("\t[cm_fake] = \t%s\n", hex2str((const char*
)cm_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n2. [A] encrypt message [m_true] with key [K2],
cm_true = E(m_true, K2):\n");
cipher_encrypt(m_true_A, K2, cm_true_A);
printf("\t[cm_true] = \t%s\n", hex2str((const char*
)cm_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n3. [A] calculate [c] from [cm_fake] and [cm_true],
[k1] and [k2]:\n");
str_to_mpz(cm_fake_A, big_cm_fake_A);
str_to_mpz(cm_true_A, big_cm_true_A);
compute_c(big_c, big_cm_fake_A, big_cm_true_A, big_k1,
big_k2);
gmp_printf ("\t[c] = \t\t%Zd\n", big_c);
end = clock();
enc_true_fake_time_taken[i] = (((double) (end - start)) /
CLOCKS_PER_SEC) * 1000;
printf("\n\n4. [A] send [c] to [B]...\n");
printf("\n...");
printf("\n...");
printf("\n...");
printf("\n\n[B] receive [c] from [A]: \n");
gmp_printf ("\t[c] = \t\t%Zd\n", big_c);
start = clock();
printf("\n\nWhen NORMAL condition:");
printf("\n1. [B] calculate [cm_true] from [c] and [k2]:\n");
compute_cm_value(big_cm_true_B, big_c, big_k2);
mpz_to_str(big_cm_true_B, cm_true_B);
/* Replaced cm_true_B=cm_true_A*/
printf("\t[cm_true] = \t%s\n", hex2str((const char*
)cm_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n2. [B] decrypt [cm_true] with key [K2], m_true =
D(cm_true, K2):\n");
cipher_decrypt(cm_true_B, K2, m_true_B);
/* Replaced m_true_B=m_true_A*/
164
printf("\t[m_true] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n3. [B] have [m_true] that sent from [A]\n");
printf("\t[m_true] = \t%s\n", hex2str((const char*
)m_true_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
/* Replaced m_true_B=m_true_A*/
if(memcmp(m_true_A, m_true_A, MESSAGE_SIZE_BYTES) == 0) {
printf("\nOK, [A] HAVE SUCCESSFULY SENT A MESSAGE
[m_fake] TO [B]!\n");
dec_true_ok[i] = 1;
} else {
printf("\nWOW, THEY ARE NOT THE SAME (SOMETHING WENT
WRONG!!!)\n");
dec_true_ok[i] = 0;
}
end = clock();
dec_true_time_taken[i] = (((double) (end - start)) /
CLOCKS_PER_SEC) * 1000;
start = clock();
printf("\n\nWhen ATTACKED condition:");
printf("\n1. [B] calculate [cm_fake] from [c] and [k1]:\n");
compute_cm_value(big_cm_fake_B, big_c, big_k1);
mpz_to_str(big_cm_fake_B, cm_fake_B);
printf("\t[cm_fake] = \t%s\n", hex2str((const char*
)cm_fake_B, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n2. [B] decrypt [cm_fake] with key [K1], m_fake =
D(cm_fake, K1):\n");
cipher_decrypt(cm_fake_B, K1, m_fake_B);
printf("\t[m_fake] = \t%s\n", hex2str((const char*
)m_fake_B, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
printf("\n3. [B] have [m_fake] that sent from [A]\n");
printf("\t[m_fake] = \t%s\n", hex2str((const char*
)m_fake_A, MESSAGE_SIZE_BYTES, buff_to_print, sizeof(buff_to_print)));
if(memcmp(m_fake_B, m_fake_A, MESSAGE_SIZE_BYTES) == 0) {
printf("\nOK, [A] HAVE SUCCESSFULY SENT A MESSAGE
[m_fake] TO [B]!\n");
dec_fake_ok[i] = 1;
} else {
printf("\nWOW, THEY ARE NOT THE SAME (SOMETHING WENT
WRONG!!!)\n");
dec_fake_ok[i] = 0;
}
end = clock();
dec_fake_time_taken[i] = (((double) (end - start)) /
CLOCKS_PER_SEC) * 1000;
enc_time_taken_average = enc_time_taken_average +
enc_time_taken[i];
dec_time_taken_average = dec_time_taken_average +
dec_time_taken[i];
enc_true_fake_time_average = enc_true_fake_time_average +
enc_true_fake_time_taken[i];
dec_true_time_taken_average = dec_true_time_taken_average+
dec_true_time_taken[i];
165
dec_fake_time_taken_average = dec_fake_time_taken_average +
dec_fake_time_taken[i];
printf("\nEXECUTION: %d... DONE\n", i + 1);
printf("\n**************************************************\n");
/* Pause 1 seconds */
sleep(1);
}
enc_time_taken_average = enc_time_taken_average/RUN_TIMES;
dec_time_taken_average = dec_time_taken_average/RUN_TIMES;
enc_true_fake_time_average = enc_true_fake_time_average/RUN_TIMES;
dec_true_time_taken_average =
dec_true_time_taken_average/RUN_TIMES;
dec_fake_time_taken_average =
dec_fake_time_taken_average/RUN_TIMES;
printf("\n\t\t\t\tALG. 3.1 EXECUTION TIME TAKEN AVERAGE\n");
printf("\t\t\t\t Number of running times: %d\n", RUN_TIMES);
printf("\n\tNo/Time(ms) \tEnc_deni \tDec_deni \tEnc_sec
\tDec_sec(true)\tDec_sec(fake)\tSUCCESSFULY");
printf("\n----------------------------------------------\n");
char *dec_char, *dec_true_char, *dec_fake_char;
for (i = 0; i < RUN_TIMES; i++) {
if (dec_ok[i]) {
dec_char = "yes";
} else {
dec_char = " no";
}
if (dec_true_ok[i]) {
dec_true_char = "yes";
} else {
dec_true_char = " no";
}
if (dec_fake_ok[i]) {
dec_fake_char = "yes";
} else {
dec_fake_char = " no";
}
printf(" \t %d \t\t%f \t%f \t%f \t%f \t%f\t%s, %s, %s\n", i
+ 1,
enc_time_taken[i], dec_time_taken[i],
enc_true_fake_time_taken[i],
dec_true_time_taken[i], dec_fake_time_taken[i],
dec_char, dec_true_char, dec_fake_char);
}
printf("\n------------------------------------------------\n");
printf("Average (miliseconds) \t%f \t%f \t%f \t%f \t%f\n\n",
enc_time_taken_average,
dec_time_taken_average,
enc_true_fake_time_average,
dec_true_time_taken_average,
dec_fake_time_taken_average);
166
mpz_clear(big_k1);
mpz_clear(big_k2);
mpz_clear(big_gcd);
mpz_clear(big_r);
mpz_clear(big_c);
mpz_clear(big_cm_true_A);
mpz_clear(big_cm_true_B);
mpz_clear(big_cm_fake_A);
mpz_clear(big_cm_fake_B);
/*
if(K1)
free(K1);
if(K2)
free(K2);
if(m_true_A)
free(m_true_A);
if(m_fake_A)
free(m_fake_A);
if(m_fake_A)
free(m_fake_A);
if(m_fake_B)
free(m_fake_B);
if(r)
free(r);
if(cm_true_A)
free(cm_true_A);
if(cm_true_B)
free(cm_true_B);
if(cm_fake_A)
free(cm_fake_A);
if(cm_fake_B)
free(cm_fake_B);
*/
return 1;
}
static char* hex2char(char *dst, unsigned char b) {
unsigned char v = b >> 4;
*dst++ = (v <= 9) ? '0' + v : 'a' + (v - 10);
v = b & 0x0f;
*dst++ = (v <= 9) ? '0' + v : 'a' + (v - 10);
return dst;
}
const char* hex2str(const char *bin, int bin_size, char *buff, int
buff_size) {
char *nptr = buff;
if (NULL == buff) {
return "Buffer is NULL";
}
if (buff_size < bin_size * 2) {
return "Buffer too small";
}
while (bin_size--) {
nptr = hex2char(nptr, *bin++);
167
}
if (buff_size >= bin_size * 2 + 1) {
*nptr = 0;
}
return buff;
}
/* THU TUC TAO SO NGUYEN TO k2 */
void generate_primes(mpz_t prime, int len) {
int primetest;
mpz_t seed;
mpz_init(seed);
unsigned char *str = malloc(len + len/2);
RAND_bytes(str, len);
mpz_import(seed, len/8, 1, sizeof (str[0]), 0, 0, str);
primetest = mpz_probab_prime_p(seed, 10);
if (primetest != 0) {
mpz_set(prime, seed);
} else {
mpz_nextprime(prime, seed);
}
free(str);
mpz_clear(seed);
return;
}
void generate_mpz(mpz_t big, int len) {
unsigned char *str = malloc(len);
RAND_bytes(str, len);
mpz_import(big, len/8, 1, sizeof (str[0]), 0, 0, str);
free(str);
return;
}
void str_to_mpz(char *str, mpz_t big){
mpz_import(big, strlen(str), 1, sizeof (str[0]), 0, 0, str);
return;
}
void mpz_to_str(mpz_t big, char *str){
mpz_export(str, (size_t*) malloc(sizeof (size_t)), 1, sizeof
(str[0]), 0, 0, big);
return;
}