Commit f95d2324 authored by Nick Mathewson's avatar Nick Mathewson 🦀
Browse files

r12332@catbus: nickm | 2007-04-10 12:24:45 -0400 

 Yet another attempted Bug 411 fix: Under some circumstances, a circuit can have cells without being active.  The likeliest is that it has been unlinked from all connections in preparation for closing.  Therefore, stop enforcing this non-invariant.


svn:r9936
parent 58a67610

src/or/circuitlist.c

+12 −17
Original line number Diff line number Diff line
@@ -80,21 +80,25 @@ orconn_circid_circuit_map_t *_last_circid_orconn_ent = NULL; 
static void

circuit_set_circid_orconn_helper(circuit_t *circ, int direction,

                                 uint16_t id,

                                 or_connection_t *conn,

                                 int active)

                                 or_connection_t *conn)

{

  orconn_circid_circuit_map_t search;

  orconn_circid_circuit_map_t *found;

  or_connection_t *old_conn, **conn_ptr;

  uint16_t old_id, *circid_ptr;

  int was_active, make_active;



  if (direction == CELL_DIRECTION_OUT) {

    conn_ptr = &circ->n_conn;

    circid_ptr = &circ->n_circ_id;

    was_active = circ->next_active_on_n_conn != NULL;

    make_active = circ->n_conn_cells.n > 0;

  } else {

    or_circuit_t *c = TO_OR_CIRCUIT(circ);

    conn_ptr = &c->p_conn;

    circid_ptr = &c->p_circ_id;

    was_active = c->next_active_on_p_conn != NULL;

    make_active = c->p_conn_cells.n > 0;

  }

  old_conn = *conn_ptr;

  old_id = *circid_ptr;
@@ -119,7 +123,7 @@ circuit_set_circid_orconn_helper(circuit_t *circ, int direction, 
      tor_free(found);

      --old_conn->n_circuits;

    }

    if (active && old_conn != conn)

    if (was_active && old_conn != conn)

      make_circuit_inactive_on_conn(circ,old_conn);

  }
@@ -144,7 +148,7 @@ circuit_set_circid_orconn_helper(circuit_t *circ, int direction, 
    found->circuit = circ;

    HT_INSERT(orconn_circid_map, &orconn_circid_circuit_map, found);

  }

  if (active && old_conn != conn)

  if (make_active && old_conn != conn)

    make_circuit_active_on_conn(circ,conn);



  ++conn->n_circuits;
@@ -157,15 +161,11 @@ void 
circuit_set_p_circid_orconn(or_circuit_t *circ, uint16_t id,

                            or_connection_t *conn)

{

  int active = circ->p_conn_cells.n > 0;



  tor_assert(bool_eq(active, circ->next_active_on_p_conn));



  circuit_set_circid_orconn_helper(TO_CIRCUIT(circ), CELL_DIRECTION_IN,

                                   id, conn, active);

                                   id, conn);



  if (conn)

    tor_assert(bool_eq(active, circ->next_active_on_p_conn));

    tor_assert(bool_eq(circ->p_conn_cells.n, circ->next_active_on_p_conn));

}



/** Set the n_conn field of a circuit <b>circ</b>, along
@@ -175,15 +175,10 @@ void 
circuit_set_n_circid_orconn(circuit_t *circ, uint16_t id,

                            or_connection_t *conn)

{

  int active = circ->n_conn_cells.n > 0;



  tor_assert(bool_eq(active, circ->next_active_on_n_conn));



  circuit_set_circid_orconn_helper(circ, CELL_DIRECTION_OUT,

                                   id, conn, active);

  circuit_set_circid_orconn_helper(circ, CELL_DIRECTION_OUT, id, conn);



  if (conn)

    tor_assert(bool_eq(active, circ->next_active_on_n_conn));

    tor_assert(bool_eq(circ->n_conn_cells.n, circ->next_active_on_n_conn));

}



/** Change the state of <b>circ</b> to <b>state</b>, adding it to or removing

src/or/or.h

+8 −4
Original line number Diff line number Diff line
@@ -1430,10 +1430,12 @@ typedef struct circuit_t { 
                                      * circuit marked for close? */



  /** Next circuit in the doubly-linked ring of circuits waiting to add

   * cells to n_conn.  NULL if we have no cells pending. */

   * cells to n_conn.  NULL if we have no cells pending, or if we're not

   * linked to an OR connection. */

  struct circuit_t *next_active_on_n_conn;

  /** Previous circuit in the doubly-linked ring of circuits waiting to add

   * cells to n_conn.  NULL if we have no cells pending. */

   * cells to n_conn.  NULL if we have no cells pending, or if we're not

   * linked to an OR connection. */

  struct circuit_t *prev_active_on_n_conn;

  struct circuit_t *next; /**< Next circuit in linked list of all circuits. */

} circuit_t;
@@ -1490,10 +1492,12 @@ typedef struct or_circuit_t { 
  circuit_t _base;



  /** Next circuit in the doubly-linked ring of circuits waiting to add

   * cells to p_conn.  NULL if we have no cells pending. */

   * cells to p_conn.  NULL if we have no cells pending, or if we're not

   * linked to an OR connection. */

  struct circuit_t *next_active_on_p_conn;

  /** Previous circuit in the doubly-linked ring of circuits waiting to add

   * cells to p_conn.  NULL if we have no cells pending. */

   * cells to p_conn.  NULL if we have no cells pending, or if we're not

   * linked to an OR connection. */

  struct circuit_t *prev_active_on_p_conn;



  /** The circuit_id used in the previous (backward) hop of this circuit. */

src/or/relay.c

+22 −12
Original line number Diff line number Diff line
@@ -1581,35 +1581,46 @@ prev_circ_on_conn_p(circuit_t *circ, or_connection_t *conn) 
}



/** Add <b>circ</b> to the list of circuits with pending cells on

 * <b>conn</b>. */

 * <b>conn</b>.   No effect if <b>circ</b> is already unlinked. */

void

make_circuit_active_on_conn(circuit_t *circ, or_connection_t *conn)

{

  tor_assert(! *prev_circ_on_conn_p(circ, conn));

  tor_assert(! *next_circ_on_conn_p(circ, conn));

  circuit_t **nextp = next_circ_on_conn_p(circ, conn);

  circuit_t **prevp = prev_circ_on_conn_p(circ, conn);



  if (*nextp && *prevp) {

    /* Already active. */

    return;

  }



  if (! conn->active_circuits) {

    conn->active_circuits = circ;

    *prev_circ_on_conn_p(circ, conn) = circ;

    *next_circ_on_conn_p(circ, conn) = circ;

    *prevp = *nextp = circ;

  } else {

    circuit_t *head = conn->active_circuits;

    circuit_t *old_tail = *prev_circ_on_conn_p(head, conn);

    *next_circ_on_conn_p(old_tail, conn) = circ;

    *next_circ_on_conn_p(circ, conn) = head;

    *nextp = head;

    *prev_circ_on_conn_p(head, conn) = circ;

    *prev_circ_on_conn_p(circ, conn) = old_tail;

    *prevp = old_tail;

  }

  assert_active_circuits_ok_paranoid(conn);

}



/** Remove <b>circ</b> to the list of circuits with pending cells on

 * <b>conn</b>. */

 * <b>conn</b>.  No effect if <b>circ</b> is already unlinked. */

void

make_circuit_inactive_on_conn(circuit_t *circ, or_connection_t *conn)

{

  circuit_t *next = *next_circ_on_conn_p(circ, conn);

  circuit_t *prev = *prev_circ_on_conn_p(circ, conn);

  circuit_t **nextp = next_circ_on_conn_p(circ, conn);

  circuit_t **prevp = prev_circ_on_conn_p(circ, conn);

  circuit_t *next = *nextp, *prev = *prevp;



  if (!next && !prev) {

    /* Already inactive. */

    return;

  }



  tor_assert(next && prev);

  tor_assert(*prev_circ_on_conn_p(next, conn) == circ);

  tor_assert(*next_circ_on_conn_p(prev, conn) == circ);
@@ -1622,8 +1633,7 @@ make_circuit_inactive_on_conn(circuit_t *circ, or_connection_t *conn) 
    if (conn->active_circuits == circ)

      conn->active_circuits = next;

  }

  *prev_circ_on_conn_p(circ, conn) = NULL;

  *next_circ_on_conn_p(circ, conn) = NULL;

  *prevp = *nextp = NULL;

  assert_active_circuits_ok_paranoid(conn);

}