Line data    Source code

       1             : /* Copyright (c) 2007-2021, The Tor Project, Inc. */
       2             : /* See LICENSE for licensing information */
       3             : 
       4             : /**
       5             :  * \file ocirc_event.c
       6             :  * \brief Publish state change messages for origin circuits
       7             :  *
       8             :  * Implements a basic publish-subscribe framework for messages about
       9             :  * the state of origin circuits.  The publisher calls the subscriber
      10             :  * callback functions synchronously.
      11             :  *
      12             :  * Although the synchronous calls might not simplify the call graph,
      13             :  * this approach improves data isolation because the publisher doesn't
      14             :  * need knowledge about the internals of subscribing subsystems.  It
      15             :  * also avoids race conditions that might occur in asynchronous
      16             :  * frameworks.
      17             :  **/
      18             : 
      19             : #include "core/or/or.h"
      20             : 
      21             : #define OCIRC_EVENT_PRIVATE
      22             : 
      23             : #include "core/or/cpath_build_state_st.h"
      24             : #include "core/or/ocirc_event.h"
      25             : #include "core/or/or_sys.h"
      26             : #include "core/or/origin_circuit_st.h"
      27             : #include "lib/subsys/subsys.h"
      28             : 
      29           1 : DECLARE_PUBLISH(ocirc_state);
      30           8 : DECLARE_PUBLISH(ocirc_chan);
      31           1 : DECLARE_PUBLISH(ocirc_cevent);
      32             : 
      33             : static void
      34          10 : ocirc_event_free(msg_aux_data_t u)
      35             : {
      36          10 :   tor_free_(u.ptr);
      37          10 : }
      38             : 
      39             : static char *
      40           2 : ocirc_state_fmt(msg_aux_data_t u)
      41             : {
      42           2 :   ocirc_state_msg_t *msg = (ocirc_state_msg_t *)u.ptr;
      43           2 :   char *s = NULL;
      44             : 
      45           2 :   tor_asprintf(&s, "<gid=%"PRIu32" state=%d onehop=%d>",
      46           2 :                msg->gid, msg->state, msg->onehop);
      47           2 :   return s;
      48             : }
      49             : 
      50             : static char *
      51          16 : ocirc_chan_fmt(msg_aux_data_t u)
      52             : {
      53          16 :   ocirc_chan_msg_t *msg = (ocirc_chan_msg_t *)u.ptr;
      54          16 :   char *s = NULL;
      55             : 
      56          16 :   tor_asprintf(&s, "<gid=%"PRIu32" chan=%"PRIu64" onehop=%d>",
      57          16 :                msg->gid, msg->chan, msg->onehop);
      58          16 :   return s;
      59             : }
      60             : 
      61             : static char *
      62           2 : ocirc_cevent_fmt(msg_aux_data_t u)
      63             : {
      64           2 :   ocirc_cevent_msg_t *msg = (ocirc_cevent_msg_t *)u.ptr;
      65           2 :   char *s = NULL;
      66             : 
      67           2 :   tor_asprintf(&s, "<gid=%"PRIu32" evtype=%d reason=%d onehop=%d>",
      68           2 :                msg->gid, msg->evtype, msg->reason, msg->onehop);
      69           2 :   return s;
      70             : }
      71             : 
      72             : static dispatch_typefns_t ocirc_state_fns = {
      73             :   .free_fn = ocirc_event_free,
      74             :   .fmt_fn = ocirc_state_fmt,
      75             : };
      76             : 
      77             : static dispatch_typefns_t ocirc_chan_fns = {
      78             :   .free_fn = ocirc_event_free,
      79             :   .fmt_fn = ocirc_chan_fmt,
      80             : };
      81             : 
      82             : static dispatch_typefns_t ocirc_cevent_fns = {
      83             :   .free_fn = ocirc_event_free,
      84             :   .fmt_fn = ocirc_cevent_fmt,
      85             : };
      86             : 
      87             : int
      88         245 : ocirc_add_pubsub(struct pubsub_connector_t *connector)
      89             : {
      90         245 :   if (DISPATCH_REGISTER_TYPE(connector, ocirc_state, &ocirc_state_fns))
      91             :     return -1;
      92         245 :   if (DISPATCH_REGISTER_TYPE(connector, ocirc_chan, &ocirc_chan_fns))
      93             :     return -1;
      94         245 :   if (DISPATCH_REGISTER_TYPE(connector, ocirc_cevent, &ocirc_cevent_fns))
      95             :     return -1;
      96         245 :   if (DISPATCH_ADD_PUB(connector, ocirc, ocirc_state))
      97             :     return -1;
      98         245 :   if (DISPATCH_ADD_PUB(connector, ocirc, ocirc_chan))
      99             :     return -1;
     100         245 :   if (DISPATCH_ADD_PUB(connector, ocirc, ocirc_cevent))
     101           0 :     return -1;
     102             :   return 0;
     103             : }
     104             : 
     105             : void
     106           1 : ocirc_state_publish(ocirc_state_msg_t *msg)
     107             : {
     108           1 :   PUBLISH(ocirc_state, msg);
     109           1 : }
     110             : 
     111             : void
     112           8 : ocirc_chan_publish(ocirc_chan_msg_t *msg)
     113             : {
     114           8 :   PUBLISH(ocirc_chan, msg);
     115           8 : }
     116             : 
     117             : void
     118           1 : ocirc_cevent_publish(ocirc_cevent_msg_t *msg)
     119             : {
     120           1 :   PUBLISH(ocirc_cevent, msg);
     121           1 : }