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#include "../lib/lib.h"
#include "../lib/lib2.h"
#include "../lib/lib3.h"
#include <time.h>
/**
* One should not restore the internal state of the MT. Given 624 bytes of
* input this would be straight forward.
* Instead one should restore more or less the first state (the seed from
* which this states arrived). To restore a previous state of the MT is
* possible. You have to go so far back, how long your ciphertext is and
* how much states you would need to encrpyt it.
*
* Since it is a 16 bit seed, one can also brute force it with 2^16
* possible values...within seconds! exhautive search Yeah!
* Theoritcal we only need 2^(16/2) values because of birthday paradox
*
**/
int main()
{
srand(time(NULL));
// try to decrypt
char plaintext[] = "Hallo du da wie geht es dir Knallkopp";
char *ciphertext = malloc(strlen(plaintext));
int length_ciphertext = mt_19937_stream_cipher_oracle(plaintext,
strlen(plaintext), ciphertext);
char *restore_pl = malloc(length_ciphertext);
char *hex_ciphertext = malloc(length_ciphertext*2+1);
hex_binary_to_string(ciphertext, hex_ciphertext, length_ciphertext);
printf("ciphertext: %s\n", hex_ciphertext);
//mt_19937_stream_cipher(ciphertext, length_ciphertext
// decrypt it
crack_mt_19937_stream_cipher_16_bit_seed(ciphertext, length_ciphertext,
restore_pl, plaintext);
printf("plaintext: %s\n", restore_pl);
// crack a MT time based password token
// well do it agian with brute force
unsigned int password_token = mt_19937_password_token();
int is_time_based = mt_19937_password_token_time_based(password_token, 1000);
printf("password token is time based %i\n", is_time_based);
}
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