int main() {
int t;
unsigned long long f;
generatePrime();
scanf("%d", &t);
while (t--) {
scanf("%llu", &f);
if(f<5)
printf("%d",2);
while(1) {
if(f%2==0)
f--;
else
f-=2;
if(preProcess(f)) {
printf("%llu\n", f);
break;
}
}
}
return 0;
}
/*
* It is a function that generates the keys for RSA algorithm
* input: mpz_t e, mpz_t, d, mpz_t n and int bitUsed;
* output: mpz_t e, mpz_t d, mpz_t n
*/
void findRSAKeys(mpz_t e, mpz_t d, mpz_t n, int bitUsed){
mpz_t p;
mpz_init(p);
mpz_t q;
mpz_init(q);
//mpz_t n;
//mpz_init(n);
mpz_t p1;
mpz_init(p1);
mpz_t q1;
mpz_init(q1);
mpz_t eulerN;
mpz_init(eulerN);
//steps according to wikipedia
//step 1
generatePrime(p, bitUsed);
while(mpz_cmp_ui(q, 0) == 0 || mpz_cmp(p, q) == 0){
generatePrime(q, bitUsed);
}
//step 2
mpz_mul(n,p,q);
//step 3
mpz_sub_ui(p1, p, 1);
mpz_sub_ui(q1, q, 1);
mpz_mul(eulerN, p1, q1);
//step 4
//mpz_t e;
//mpz_init(e);
findESimple(e, eulerN);
//gmp_printf("e is %Zd\n", e);
//step 5
mpz_t g, s;
mpz_init(g);
mpz_init(s);
mpz_gcdext(g, s, d, eulerN, e);
}
static int generate_pwd_shares(sc_card_t *card, char **pwd, int *pwdlen, int password_shares_threshold, int password_shares_total)
{
int r, i;
BIGNUM prime;
BIGNUM secret;
char buf[64];
char hex[64];
int l;
secret_share_t *shares = NULL;
secret_share_t *sp;
u8 rngseed[16];
printf( "\nThe DKEK will be enciphered using a randomly generated 64 bit password.\n");
printf( "This password is split using a (%i-of-%i) threshold scheme.\n\n", password_shares_threshold, password_shares_total);
printf( "Please keep the generated and encrypted DKEK file in a safe location. We also recommend \n");
printf( "to keep a paper printout, in case the electronic version becomes unavailable. A printable version\n");
printf( "of the file can be generated using \"openssl base64 -in <filename>\".\n");
printf("\n\nPress <enter> to continue");
waitForEnterKeyPressed();
*pwd = calloc(1, 8);
*pwdlen = 8;
r = sc_get_challenge(card, *pwd, 8);
if (r < 0) {
printf("Error generating random key failed with ", sc_strerror(r));
OPENSSL_cleanse(pwd, *pwdlen);
free(pwd);
return r;
}
**pwd |= 0x80;
/*
* Initialize prime and secret
*/
BN_init(&prime);
BN_init(&secret);
/*
* Encode the secret value
*/
BN_bin2bn(*pwd, *pwdlen, &secret);
/*
* Generate seed and calculate a prime depending on the size of the secret
*/
r = sc_get_challenge(card, rngseed, 16);
if (r < 0) {
printf("Error generating random seed failed with ", sc_strerror(r));
OPENSSL_cleanse(pwd, *pwdlen);
free(pwd);
return r;
}
generatePrime(&prime, &secret, password_shares_total, rngseed);
// Allocate data buffer for the generated shares
shares = malloc(password_shares_total * sizeof(secret_share_t));
createShares(&secret, password_shares_threshold, password_shares_total, prime, shares);
sp = shares;
for (i = 0; i < password_shares_total; i++) {
clearScreen();
printf("Press <enter> to display key share %i of %i\n\n", i + 1, password_shares_total);
waitForEnterKeyPressed();
clearScreen();
printf("Share %i of %i\n\n", i + 1, password_shares_total);
l = BN_bn2bin(&prime, buf);
sc_bin_to_hex(buf, l, hex, 64, ':');
printf("\nPrime : %s\n", hex);
printf("Share ID : %s\n", BN_bn2dec(&(sp->x)));
l = BN_bn2bin(&(sp->y), buf);
sc_bin_to_hex(buf, l, hex, 64, ':');
printf("Share value : %s\n", hex);
printf("\n\nPlease note ALL values above and press <enter> when finished");
waitForEnterKeyPressed();
sp++;
}
clearScreen();
cleanUpShares(shares, password_shares_total);
BN_clear_free(&prime);
BN_clear_free(&secret);
return 0;
}
int main(){
generatePrime(); // generating primes from 1 to 30000
srand((unsigned int)time(NULL)); // For rand() function to generate unique random number
pid_t childPID[250], mainPID; // pids of all childs and parent
int partochild[500]; // File descriptors of parent to child pipes
int childtopar[500]; // File descriptors of child to parent pipes
int indexTopipe; // Index of the corresponding pipe of the child
int i,j;
int err; // Error number for error checking
char buff[MAX_SIZE]; // Buff used for reading and writing to the pipe
// Reading input
printf("Enter the value of k(Number of child processes) and n = Number of Primes to be found\n");
while(1){
scanf("%d %d",&k,&n);
if(k > 250 || k <=0 || n > 500 || n <=0){
printf("Invalid input(out of scope) try again!\n");
}
else break;
}
// n = 2*k;
mainPID = getpid(); // Storing pid of the parent
// Creating k childs
for (i = 0; i < k; ++i)
{
if(pipe(&partochild[2*i]) == -1) // creating pipes from parent to child
{
perror("Error in creating pipe!");
exit(0);
}
if(pipe2(&childtopar[2*i], O_NONBLOCK) == -1) // Creating pipes from child to parent in Non Blocking mode
{
perror("Error in creating pipe!");
exit(0);
}
childPID[i] = fork(); // Creating child
if(childPID[i] < 0){ // Error
perror("Error in forking children!");
exit(0);
}
else if(!childPID[i]){ // Child process
indexTopipe = 2*i; // Assigning pipe index in child
break;
}
}
if(getpid() == mainPID){ // Parent Process
while(1){
for (i = 0; i < k; ++i)
{
if(read(childtopar[2*i], buff, MAX_SIZE) == -1){ // Skipping the read if pipe empty
continue;
}
int status = atoi(buff); // Reading from child
if(status == AVAILABLE){ // Available
for (j = 0; j < k; ++j)
{
sprintf(buff,"%d",rand()%30001); // Generating random numbers to sent to child
if(write(partochild[2*i+1], buff, MAX_SIZE) == -1){
perror("Error in writing in pipes!");
exit(0);
}
}
}
else if(status == BUSY){ // Busy
//Skip this child process
}
else{
insertintoprimes(status); // Checking if prime exists from first
if(primeCount >= n){ // N primes found so killing all child processes and printing n primes
for (j = 0; j < k; ++j)
{
if(kill(childPID[j],SIGKILL) == -1){
perror("");
}
}
printf("\nRespective %d prime numbers are as follows:\n",n);
for (j = 0; j < n; ++j)
{
printf("%d. %d\n",j+1,FoundPrimes[j]);
}
printf("\n");
exit(0);
}
}
}
}
}
else{ // Child Process
int numbers[100]; // Input from parent
close(partochild[indexTopipe+1]); // Closing write end of parent to child in child process as not needed
close(childtopar[indexTopipe]); // Closing read end of child to parent in child process as not needed
while(1){
if(write(childtopar[indexTopipe+1],"30001",MAX_SIZE) == -1){ // Sending Available signal
perror("Error in writing in pipes!");
exit(0);
}
for (i = 0; i < k; ++i) // reading k numbers from parent
{
if(read(partochild[indexTopipe], buff, MAX_SIZE) == -1){
perror("Error in reading pipes!");
exit(0);
}
numbers[i] = atoi(buff);
}
if(write(childtopar[indexTopipe+1],"30002",MAX_SIZE) == -1){ // Sending Busy Signal
perror("Error in writing in pipes!");
exit(0);
}
for (i = 0; i < k; ++i) // Checking for the primality of the k numbers and sending them to parent one by one
{
if(isprime[numbers[i]]){
//printf("Prime = %d child = %d\n",numbers[i],getpid());
sprintf(buff,"%d",numbers[i]);
if(write(childtopar[indexTopipe+1], buff, MAX_SIZE) == -1){
perror("Error in writing in pipes!");
exit(0);
}
}
}
}
}
return 0;
}
static int generate_pwd_shares(sc_card_t *card, char **pwd, int *pwdlen, int password_shares_threshold, int password_shares_total)
{
int r, i;
BIGNUM *prime;
BIGNUM *secret;
unsigned char buf[64];
char hex[64];
int l;
secret_share_t *shares = NULL;
secret_share_t *sp;
u8 rngseed[16];
if ((password_shares_threshold == -1) || (password_shares_total == -1)) {
fprintf(stderr, "Must specify both, --pwd-shares-total and --pwd-shares-threshold\n");
return -1;
}
if (password_shares_total < 3) {
fprintf(stderr, "--pwd-shares-total must be 3 or larger\n");
return -1;
}
if (password_shares_threshold < 2) {
fprintf(stderr, "--pwd-shares-threshold must 2 or larger\n");
return -1;
}
if (password_shares_threshold > password_shares_total) {
fprintf(stderr, "--pwd-shares-threshold must be smaller or equal to --pwd-shares-total\n");
return -1;
}
printf( "\nThe DKEK will be enciphered using a randomly generated 64 bit password.\n");
printf( "This password is split using a (%i-of-%i) threshold scheme.\n\n", password_shares_threshold, password_shares_total);
printf( "Please keep the generated and encrypted DKEK file in a safe location. We also recommend \n");
printf( "to keep a paper printout, in case the electronic version becomes unavailable. A printable version\n");
printf( "of the file can be generated using \"openssl base64 -in <filename>\".\n");
printf("\n\nPress <enter> to continue");
waitForEnterKeyPressed();
*pwd = calloc(1, 8);
*pwdlen = 8;
r = sc_get_challenge(card, (unsigned char *)*pwd, 8);
if (r < 0) {
printf("Error generating random key failed with %s", sc_strerror(r));
OPENSSL_cleanse(*pwd, *pwdlen);
free(*pwd);
return r;
}
**pwd &= 0x7F; // Make sure the bit size of the secret is not bigger than 63 bits
/*
* Initialize prime and secret
*/
prime = BN_new();
secret = BN_new();
/*
* Encode the secret value
*/
BN_bin2bn((unsigned char *)*pwd, *pwdlen, secret);
/*
* Generate seed and calculate a prime depending on the size of the secret
*/
r = sc_get_challenge(card, rngseed, SEED_LENGTH);
if (r < 0) {
printf("Error generating random seed failed with %s", sc_strerror(r));
OPENSSL_cleanse(*pwd, *pwdlen);
free(*pwd);
return r;
}
r = generatePrime(prime, secret, 64, rngseed, SEED_LENGTH);
if (r < 0) {
printf("Error generating valid prime number. Please try again.");
OPENSSL_cleanse(*pwd, *pwdlen);
free(*pwd);
return r;
}
// Allocate data buffer for the generated shares
shares = malloc(password_shares_total * sizeof(secret_share_t));
createShares(secret, password_shares_threshold, password_shares_total, prime, shares);
sp = shares;
for (i = 0; i < password_shares_total; i++) {
clearScreen();
printf("Press <enter> to display key share %i of %i\n\n", i + 1, password_shares_total);
waitForEnterKeyPressed();
clearScreen();
printf("Share %i of %i\n\n", i + 1, password_shares_total);
l = BN_bn2bin(prime, buf);
sc_bin_to_hex(buf, l, hex, 64, ':');
printf("\nPrime : %s\n", hex);
printf("Share ID : %s\n", BN_bn2dec((sp->x)));
l = BN_bn2bin((sp->y), buf);
sc_bin_to_hex(buf, l, hex, 64, ':');
printf("Share value : %s\n", hex);
printf("\n\nPlease note ALL values above and press <enter> when finished");
waitForEnterKeyPressed();
sp++;
}
clearScreen();
cleanUpShares(shares, password_shares_total);
BN_clear_free(prime);
BN_clear_free(secret);
return 0;
}
