Commit 72aa23a9 authored by George Kadianakis's avatar George Kadianakis
Browse files

circpad: Be smarter on when to send back STOP cells.

parent 27d6b3ae

changes/bug40435

0 → 100644
+4 −0
Original line number Original line Diff line number Diff line 
  o Minor bugfixes (circuit padding):

    - Don't send STOP circuit padding cells when the other side has already

      shut down the corresponding padding machine. Fixes bug 40435; bugfix on

      0.4.0.1-alpha.
 
 No newline at end of file

src/core/or/circuitpadding.c

+15 −4
Original line number Original line Diff line number Diff line
@@ -2967,6 +2967,8 @@ signed_error_t 
circpad_handle_padding_negotiate(circuit_t *circ, cell_t *cell)

circpad_handle_padding_negotiate(circuit_t *circ, cell_t *cell)

{

{

  int retval = 0;

  int retval = 0;

  /* Should we send back a STOP cell? */

  bool respond_with_stop = true;

  circpad_negotiate_t *negotiate;

  circpad_negotiate_t *negotiate;





  if (CIRCUIT_IS_ORIGIN(circ)) {

  if (CIRCUIT_IS_ORIGIN(circ)) {
@@ -2992,6 +2994,12 @@ circpad_handle_padding_negotiate(circuit_t *circ, cell_t *cell) 
               negotiate->machine_type, negotiate->machine_ctr);

               negotiate->machine_type, negotiate->machine_ctr);

      goto done;

      goto done;

    }

    }



    /* If we reached this point we received a STOP command from an old or

       unknown machine. Don't reply with our own STOP since there is no one to

       handle it on the other end */

    respond_with_stop = false;



    if (negotiate->machine_ctr <= circ->padding_machine_ctr) {

    if (negotiate->machine_ctr <= circ->padding_machine_ctr) {

      log_info(LD_CIRC, "Received STOP command for old machine %u, ctr %u",

      log_info(LD_CIRC, "Received STOP command for old machine %u, ctr %u",

               negotiate->machine_type, negotiate->machine_ctr);

               negotiate->machine_type, negotiate->machine_ctr);
@@ -3023,10 +3031,13 @@ circpad_handle_padding_negotiate(circuit_t *circ, cell_t *cell) 
    retval = -1;

    retval = -1;





  done:

  done:

    if (respond_with_stop) {

      circpad_padding_negotiated(circ, negotiate->machine_type,

      circpad_padding_negotiated(circ, negotiate->machine_type,

                    negotiate->command,

                    negotiate->command,

                    (retval == 0) ? CIRCPAD_RESPONSE_OK : CIRCPAD_RESPONSE_ERR,

                    (retval == 0) ? CIRCPAD_RESPONSE_OK : CIRCPAD_RESPONSE_ERR,

                    negotiate->machine_ctr);

                    negotiate->machine_ctr);

    }



    circpad_negotiate_free(negotiate);

    circpad_negotiate_free(negotiate);





    return retval;

    return retval;

src/test/test_circuitpadding.c

+2 −4
Original line number Original line Diff line number Diff line
@@ -1367,7 +1367,7 @@ test_circuitpadding_wronghop(void *arg) 
  tt_ptr_op(client_side->padding_info[0], OP_NE, NULL);

  tt_ptr_op(client_side->padding_info[0], OP_NE, NULL);

  tt_ptr_op(relay_side->padding_machine[0], OP_NE, NULL);

  tt_ptr_op(relay_side->padding_machine[0], OP_NE, NULL);

  tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL);

  tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL);

  tt_int_op(n_relay_cells, OP_EQ, 3);

  tt_int_op(n_relay_cells, OP_EQ, 2);

  tt_int_op(n_client_cells, OP_EQ, 2);

  tt_int_op(n_client_cells, OP_EQ, 2);





  /* 6. Sending negotiated command to relay does nothing */

  /* 6. Sending negotiated command to relay does nothing */
@@ -1396,11 +1396,9 @@ test_circuitpadding_wronghop(void *arg) 
  /* verify no padding was negotiated */

  /* verify no padding was negotiated */

  tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL);

  tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL);

  tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL);

  tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL);

  tt_int_op(n_relay_cells, OP_EQ, 3);

  tt_int_op(n_client_cells, OP_EQ, 2);





  /* verify no echo was sent */

  /* verify no echo was sent */

  tt_int_op(n_relay_cells, OP_EQ, 3);

  tt_int_op(n_relay_cells, OP_EQ, 2);

  tt_int_op(n_client_cells, OP_EQ, 2);

  tt_int_op(n_client_cells, OP_EQ, 2);





  /* Finish circuit */

  /* Finish circuit */