Commit abdc6aed authored by Nick Mathewson's avatar Nick Mathewson 🐚
Browse files

Merge branch 'ticket28851_035_squashed' into maint-0.3.5

parents 98736cf3 b82717b2

changes/ticket28851

0 → 100644
+4 −0
Original line number Diff line number Diff line 
  o Minor features (performance):

    - Stop re-validating our hardcoded Diffie-Hellman parameters on every

      startup. Doing this wasted time and cycles, especially on low-powered

      devices. Closes ticket 28851.

src/lib/crypt_ops/crypto_dh_openssl.c

+6 −0
Original line number Diff line number Diff line
@@ -45,6 +45,8 @@ static BIGNUM *dh_param_p_tls = NULL; 
/** Shared G parameter for our DH key exchanges. */

static BIGNUM *dh_param_g = NULL;



/* This function is disabled unless we change the DH parameters. */

#if 0

/** Validate a given set of Diffie-Hellman parameters.  This is moderately

 * computationally expensive (milliseconds), so should only be called when

 * the DH parameters change. Returns 0 on success, * -1 on failure.
@@ -98,6 +100,7 @@ crypto_validate_dh_params(const BIGNUM *p, const BIGNUM *g) 
    DH_free(dh);

  return ret;

}

#endif



/**

 * Helper: convert <b>hex<b> to a bignum, and return it.  Assert that the
@@ -151,8 +154,11 @@ crypto_dh_init_openssl(void) 
  dh_param_p = bignum_from_hex(OAKLEY_PRIME_2);

  dh_param_p_tls = bignum_from_hex(TLS_DH_PRIME);



  /* Checks below are disabled unless we change the hardcoded DH parameters. */

#if 0

  tor_assert(0 == crypto_validate_dh_params(dh_param_p, dh_param_g));

  tor_assert(0 == crypto_validate_dh_params(dh_param_p_tls, dh_param_g));

#endif

}



/** Number of bits to use when choosing the x or y value in a Diffie-Hellman