Commit 84c3d114 authored by Matthieu Dien's avatar Matthieu Dien
Browse files

Agg bignum from str and md5

parent 92b11924

src/bignum.c

+20 −0
Original line number Diff line number Diff line 
#include <stdlib.h>

#include <stdio.h>

#include <gmp.h>



typedef mpz_t* bignum_t;
@@ -15,6 +16,13 @@ bignum_t bignum_from_int(int n){ 
  return x;

}



bignum_t bignum_from_str(char* s, int base){

  bignum_t x = (bignum_t) malloc(sizeof(mpz_t));

  mpz_set_str(*x, s, base);

  return x;

}





bignum_t bignum_copy(bignum_t x){

  bignum_t y = bignum_zero();

  mpz_set(*y, *x);
@@ -97,6 +105,18 @@ bignum_t bignum_gcd(bignum_t a, bignum_t b){ 
  return g;

}



bignum_t bignum_from_MD5(unsigned char* md5sum, size_t len){

  char s[100];

  size_t r = 0;

  bignum_t res = bignum_zero();



  for(size_t i = 0; i < len; i++)

    r = r + sprintf(s+r, "%x", md5sum[i]);



  mpz_set_str(*res, s, 16);

  return res;

}



char* bignum_to_str(bignum_t x){

  return mpz_get_str(NULL, 10, *x);

}

src/bignum.h

+3 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ typedef mpz_t* bignum_t; 


bignum_t bignum_zero();

bignum_t bignum_from_int(int);

bignum_t bignum_from_str(char*, int);

bignum_t bignum_copy(bignum_t);

void bignum_destroy(bignum_t);
@@ -26,5 +27,7 @@ bignum_t bignum_pow(bignum_t, bignum_t); 


bignum_t bignum_gcd(bignum_t, bignum_t);



bignum_t bignum_from_MD5(unsigned char* md5sum, size_t len);



char* bignum_to_str(bignum_t);

#endif

tests/bignum_tests.c

+17 −1
Original line number Diff line number Diff line 
#include <stdio.h>

#include <string.h>

#include <assert.h>

#include <openssl/md5.h>

#include "bignum.h"



#define BG(n) bignum_from_int(n)
@@ -35,11 +36,26 @@ void test_str(){ 
  printf("test_str OK\n");

}



void test_from_md5(){

  bignum_t t, tt;

  unsigned char digest[MD5_DIGEST_LENGTH];

  char x[] = "coucou";

  char xx[] = "719d8179d0cea7774b518d58fd52fc4";

  MD5((const unsigned char*)x, 7, digest);

  t = bignum_from_MD5(digest, MD5_DIGEST_LENGTH);

  tt = bignum_from_str(xx, 16);

  

  assert(bignum_eq(t, tt));

  

  printf("test_from_md5 OK\n");

}



int main(){

  printf("=== BIGNUM tests ===\n");

  test_arithmetic();

  test_cmp();

  test_str();

  test_from_md5();

  

  return 0;

}