src/core/or/entry_connection_st.h

   1 /* Copyright (c) 2001 Matej Pfajfar.
   2  * Copyright (c) 2001-2004, Roger Dingledine.
   3  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   4  * Copyright (c) 2007-2021, The Tor Project, Inc. */
   5 /* See LICENSE for licensing information */
   6
   7 /**
   8  * @file entry_connection_st.h
   9  * @brief Entry connection structure.
  10  **/
  11
  12 #ifndef ENTRY_CONNECTION_ST_H
  13 #define ENTRY_CONNECTION_ST_H
  14
  15 #include "core/or/edge_connection_st.h"
  16
  17 /** Subtype of edge_connection_t for an "entry connection" -- that is, a SOCKS
  18  * connection, a DNS request, a TransPort connection or a NATD connection */
  19 struct entry_connection_t {
  20   struct edge_connection_t edge_;
  21
  22   /** Nickname of planned exit node -- used with .exit support. */
  23   /* XXX prop220: we need to make chosen_exit_name able to encode Ed IDs too.
  24    * That's logically part of the UI parts for prop220 though. */
  25   char *chosen_exit_name;
  26
  27   socks_request_t *socks_request; /**< SOCKS structure describing request (AP
  28                                    * only.) */
  29
  30   /* === Isolation related, AP only. === */
  31   entry_port_cfg_t entry_cfg;
  32   /** AP only: The newnym epoch in which we created this connection. */
  33   unsigned nym_epoch;
  34
  35   /** AP only: The original requested address before we rewrote it. */
  36   char *original_dest_address;
  37   /* Other fields to isolate on already exist.  The ClientAddr is addr.  The
  38      ClientProtocol is a combination of type and socks_request->
  39      socks_version.  SocksAuth is socks_request->username/password.
  40      DestAddr is in socks_request->address. */
  41
  42   /** Number of times we've reassigned this application connection to
  43    * a new circuit. We keep track because the timeout is longer if we've
  44    * already retried several times. */
  45   uint8_t num_socks_retries;
  46
  47   /** For AP connections only: buffer for data that we have sent
  48    * optimistically, which we might need to re-send if we have to
  49    * retry this connection. */
  50   struct buf_t *pending_optimistic_data;
  51   /* For AP connections only: buffer for data that we previously sent
  52   * optimistically which we are currently re-sending as we retry this
  53   * connection. */
  54   struct buf_t *sending_optimistic_data;
  55
  56   /** If this is a DNSPort connection, this field holds the pending DNS
  57    * request that we're going to try to answer.  */
  58   struct evdns_server_request *dns_server_request;
  59
  60 #define DEBUGGING_17659
  61
  62 #ifdef DEBUGGING_17659
  63   uint16_t marked_pending_circ_line;
  64   const char *marked_pending_circ_file;
  65 #endif
  66
  67 #define NUM_CIRCUITS_LAUNCHED_THRESHOLD 10
  68   /** Number of times we've launched a circuit to handle this stream. If
  69     * it gets too high, that could indicate an inconsistency between our
  70     * "launch a circuit to handle this stream" logic and our "attach our
  71     * stream to one of the available circuits" logic. */
  72   unsigned int num_circuits_launched:4;
  73
  74   /** True iff this stream must attach to a one-hop circuit (e.g. for
  75    * begin_dir). */
  76   unsigned int want_onehop:1;
  77   /** True iff this stream should use a BEGIN_DIR relay command to establish
  78    * itself rather than BEGIN (either via onehop or via a whole circuit). */
  79   unsigned int use_begindir:1;
  80
  81   /** For AP connections only. If 1, and we fail to reach the chosen exit,
  82    * stop requiring it. */
  83   unsigned int chosen_exit_optional:1;
  84   /** For AP connections only. If non-zero, this exit node was picked as
  85    * a result of the TrackHostExit, and the value decrements every time
  86    * we fail to complete a circuit to our chosen exit -- if it reaches
  87    * zero, abandon the associated mapaddress. */
  88   unsigned int chosen_exit_retries:3;
  89
  90   /** True iff this is an AP connection that came from a transparent or
  91    * NATd connection */
  92   unsigned int is_transparent_ap:1;
  93
  94   /** For AP connections only: Set if this connection's target exit node
  95    * allows optimistic data (that is, data sent on this stream before
  96    * the exit has sent a CONNECTED cell) and we have chosen to use it.
  97    */
  98   unsigned int may_use_optimistic_data : 1;
  99 };
 100
 101 /** Cast a entry_connection_t subtype pointer to a edge_connection_t **/
 102 #define ENTRY_TO_EDGE_CONN(c) (&(((c))->edge_))
 103
 104 #endif /* !defined(ENTRY_CONNECTION_ST_H) */