1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
|
/* Copyright (c) 2007-2020, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file btrack_orconn.c
* \brief Bootstrap tracker for OR connections
*
* Track state changes of OR connections, as published by the
* connection subsystem. Also track circuit launch events, because
* they're one of the few ways to discover the association between a
* channel (and OR connection) and a circuit.
*
* We track all OR connections that we receive events for, whether or
* not they're carrying origin circuits. (An OR connection might
* carry origin circuits only after we first find out about that
* connection.)
*
* All origin ORCONN events update the "any" state variables, while
* only application ORCONN events update the "ap" state variables (and
* also update the "any") variables.
*
* We do this because we want to report the first increments of
* connection progress as the earliest bootstrap phases. This results
* in a better user experience because failures here translate into
* zero or very small amounts of displayed progress, instead of
* progress stuck near completion. The first connection to a relay
* might be a one-hop circuit for directory lookups, or it might be a
* connection for an application circuit because we already have
* enough directory info to build an application circuit.
*
* We call functions in btrack_orconn_cevent.c to generate the actual
* controller events, because some of the state decoding we need to do
* is complicated.
**/
#include <stdbool.h>
#include "core/or/or.h"
#define BTRACK_ORCONN_PRIVATE
#include "core/or/ocirc_event.h"
#include "core/or/orconn_event.h"
#include "feature/control/btrack_orconn.h"
#include "feature/control/btrack_orconn_cevent.h"
#include "feature/control/btrack_orconn_maps.h"
#include "lib/log/log.h"
#include "lib/pubsub/pubsub.h"
DECLARE_SUBSCRIBE(orconn_state, bto_state_rcvr);
DECLARE_SUBSCRIBE(orconn_status, bto_status_rcvr);
DECLARE_SUBSCRIBE(ocirc_chan, bto_chan_rcvr);
/** Pair of a best ORCONN GID and with its state */
typedef struct bto_best_t {
uint64_t gid;
int state;
} bto_best_t;
/** GID and state of the best ORCONN we've seen so far */
static bto_best_t best_any = { 0, -1 };
/** GID and state of the best application circuit ORCONN we've seen so far */
static bto_best_t best_ap = { 0, -1 };
/**
* Update a cached state of a best ORCONN progress we've seen so far.
*
* Return true if the new state is better than the old.
**/
static bool
bto_update_best(const bt_orconn_t *bto, bto_best_t *best, const char *type)
{
if (bto->state < best->state)
return false;
/* Update even if we won't change best->state, because it's more
* recent information that a particular connection transitioned to
* that state. */
best->gid = bto->gid;
if (bto->state > best->state) {
log_info(LD_BTRACK, "ORCONN BEST_%s state %d->%d gid=%"PRIu64, type,
best->state, bto->state, bto->gid);
best->state = bto->state;
return true;
}
return false;
}
/**
* Update cached states of best ORCONN progress we've seen
*
* Only update the application ORCONN state if we know it's carrying
* an application circuit.
**/
static void
bto_update_bests(const bt_orconn_t *bto)
{
tor_assert(bto->is_orig);
if (bto_update_best(bto, &best_any, "ANY"))
bto_cevent_anyconn(bto);
if (!bto->is_onehop && bto_update_best(bto, &best_ap, "AP"))
bto_cevent_apconn(bto);
}
/** Reset cached "best" values */
static void
bto_reset_bests(void)
{
best_any.gid = best_ap.gid = 0;
best_any.state = best_ap.state = -1;
}
/**
* Update cached states of ORCONNs from the incoming message. This
* message comes from code in connection_or.c.
**/
static void
bto_state_rcvr(const msg_t *msg, const orconn_state_msg_t *arg)
{
bt_orconn_t *bto;
(void)msg;
bto = bto_find_or_new(arg->gid, arg->chan);
log_debug(LD_BTRACK, "ORCONN gid=%"PRIu64" chan=%"PRIu64
" proxy_type=%d state=%d",
arg->gid, arg->chan, arg->proxy_type, arg->state);
bto->proxy_type = arg->proxy_type;
bto->state = arg->state;
if (bto->is_orig)
bto_update_bests(bto);
}
/**
* Delete a cached ORCONN state if we get an incoming message saying
* the ORCONN is failed or closed. This message comes from code in
* control.c.
**/
static void
bto_status_rcvr(const msg_t *msg, const orconn_status_msg_t *arg)
{
(void)msg;
switch (arg->status) {
case OR_CONN_EVENT_FAILED:
case OR_CONN_EVENT_CLOSED:
log_info(LD_BTRACK, "ORCONN DELETE gid=%"PRIu64" status=%d reason=%d",
arg->gid, arg->status, arg->reason);
return bto_delete(arg->gid);
default:
break;
}
}
/**
* Create or update a cached ORCONN state for a newly launched
* connection, including whether it's launched by an origin circuit
* and whether it's a one-hop circuit.
**/
static void
bto_chan_rcvr(const msg_t *msg, const ocirc_chan_msg_t *arg)
{
bt_orconn_t *bto;
(void)msg;
bto = bto_find_or_new(0, arg->chan);
if (!bto->is_orig || (bto->is_onehop && !arg->onehop)) {
log_debug(LD_BTRACK, "ORCONN LAUNCH chan=%"PRIu64" onehop=%d",
arg->chan, arg->onehop);
}
bto->is_orig = true;
if (!arg->onehop)
bto->is_onehop = false;
bto_update_bests(bto);
}
/**
* Initialize the hash maps and subscribe to ORCONN and origin
* circuit events.
**/
int
btrack_orconn_init(void)
{
bto_init_maps();
return 0;
}
int
btrack_orconn_add_pubsub(pubsub_connector_t *connector)
{
if (DISPATCH_ADD_SUB(connector, orconn, orconn_state))
return -1;
if (DISPATCH_ADD_SUB(connector, orconn, orconn_status))
return -1;
if (DISPATCH_ADD_SUB(connector, ocirc, ocirc_chan))
return -1;
return 0;
}
/** Clear the hash maps and reset the "best" states */
void
btrack_orconn_fini(void)
{
bto_clear_maps();
bto_reset_bests();
bto_cevent_reset();
}
|
