Commit 485cab86 authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Merge remote branch 'public/rand_double2'

parents bea55766 b111a7cd

src/common/crypto.c

+20 −0
Original line number Diff line number Diff line
@@ -2067,6 +2067,26 @@ crypto_rand_uint64(uint64_t max) 
  }

}



/** Return a pseudorandom double d, chosen uniformly from the range

 * 0.0 <= d < 1.0.

 */

double

crypto_rand_double(void)

{

  /* We just use an unsigned int here; we don't really care about getting

   * more than 32 bits of resolution */

  unsigned int uint;

  crypto_rand((char*)&uint, sizeof(uint));

#if SIZEOF_INT == 4

#define UINT_MAX_AS_DOUBLE 4294967296.0

#elif SIZEOF_INT == 8

#define UINT_MAX_AS_DOUBLE 1.8446744073709552e+19

#else

#error SIZEOF_INT is neither 4 nor 8

#endif

  return ((double)uint) / UINT_MAX_AS_DOUBLE;

}



/** Generate and return a new random hostname starting with <b>prefix</b>,

 * ending with <b>suffix</b>, and containing no less than

 * <b>min_rand_len</b> and no more than <b>max_rand_len</b> random base32

src/common/crypto.h

+1 −0
Original line number Diff line number Diff line
@@ -210,6 +210,7 @@ int crypto_seed_rng(int startup); 
int crypto_rand(char *to, size_t n);

int crypto_rand_int(unsigned int max);

uint64_t crypto_rand_uint64(uint64_t max);

double crypto_rand_double(void);



char *crypto_random_hostname(int min_rand_len, int max_rand_len,

                             const char *prefix, const char *suffix);

src/or/circuitbuild.c

+4 −2
Original line number Diff line number Diff line
@@ -815,18 +815,20 @@ build_time_t 
circuit_build_times_generate_sample(circuit_build_times_t *cbt,

                                    double q_lo, double q_hi)

{

  uint64_t r = crypto_rand_uint64(UINT64_MAX-1);

  double randval = crypto_rand_double();

  build_time_t ret;

  double u;



  /* Generate between [q_lo, q_hi) */

  /*XXXX This is what nextafter is supposed to be for; we should use it on the

   * platforms that support it. */

  q_hi -= 1.0/(INT32_MAX);



  tor_assert(q_lo >= 0);

  tor_assert(q_hi < 1);

  tor_assert(q_lo < q_hi);



  u = q_lo + ((q_hi-q_lo)*r)/(1.0*UINT64_MAX);

  u = q_lo + (q_hi-q_lo)*randval;



  tor_assert(0 <= u && u < 1.0);

  /* circuit_build_times_calculate_timeout returns <= INT32_MAX */

src/test/test_crypto.c

+4 −0
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ test_crypto_rng(void) 
{

  int i, j, allok;

  char data1[100], data2[100];

  double d;



  /* Try out RNG. */

  test_assert(! crypto_seed_rng(0));
@@ -76,6 +77,9 @@ test_crypto_rng(void) 
    big = crypto_rand_uint64(U64_LITERAL(5));

    if (big >= 5)

      allok = 0;

    d = crypto_rand_double();

    test_assert(d >= 0);

    test_assert(d < 1.0);

    host = crypto_random_hostname(3,8,"www.",".onion");

    if (strcmpstart(host,"www.") ||

        strcmpend(host,".onion") ||