[tor-commits] [tor/master] Add ORCONN event pubsub system
nickm at torproject.org
nickm at torproject.org
Fri Dec 21 19:28:10 UTC 2018
commit 271b50f54abac7af44e3e54589ff965d3cdac816
Author: Taylor Yu <catalyst at torproject.org>
Date: Sun Dec 16 16:05:58 2018 -0600
Add ORCONN event pubsub system
Add a publish-subscribe subsystem to publish messages about changes to
OR connections.
connection_or_change_state() in connection_or.c and
control_event_or_conn_event() in control.c publish messages to this
subsystem via helper functions.
Move state constants from connection_or.h to orconn_state.h so that
subscribers don't have to include all of connection_or.h to take
actions based on changes in OR connection state. Move event constants
from control.h for similar reasons.
Part of ticket 27167.
---
src/app/main/subsystem_list.c | 2 +
src/core/include.am | 3 ++
src/core/mainloop/connection.c | 2 +-
src/core/or/connection_or.c | 73 +++++++++++++++++++++----
src/core/or/connection_or.h | 30 ++---------
src/core/or/orconn_event.c | 81 ++++++++++++++++++++++++++++
src/core/or/orconn_event.h | 120 +++++++++++++++++++++++++++++++++++++++++
src/core/or/orconn_event_sys.h | 12 +++++
src/feature/control/control.h | 12 +----
src/feature/relay/ext_orport.c | 2 +-
10 files changed, 288 insertions(+), 49 deletions(-)
diff --git a/src/app/main/subsystem_list.c b/src/app/main/subsystem_list.c
index 8640329e9..185873809 100644
--- a/src/app/main/subsystem_list.c
+++ b/src/app/main/subsystem_list.c
@@ -8,6 +8,7 @@
#include "lib/cc/compat_compiler.h"
#include "lib/cc/torint.h"
+#include "core/or/orconn_event_sys.h"
#include "lib/compress/compress_sys.h"
#include "lib/crypt_ops/crypto_sys.h"
#include "lib/err/torerr_sys.h"
@@ -35,6 +36,7 @@ const subsys_fns_t *tor_subsystems[] = {
&sys_compress, /* -70 */
&sys_crypto, /* -60 */
&sys_tortls, /* -50 */
+ &sys_orconn_event, /* -40 */
};
const unsigned n_tor_subsystems = ARRAY_LENGTH(tor_subsystems);
diff --git a/src/core/include.am b/src/core/include.am
index 3cd6e83ed..a1fae7360 100644
--- a/src/core/include.am
+++ b/src/core/include.am
@@ -39,6 +39,7 @@ LIBTOR_APP_A_SOURCES = \
src/core/or/connection_or.c \
src/core/or/dos.c \
src/core/or/onion.c \
+ src/core/or/orconn_event.c \
src/core/or/policies.c \
src/core/or/protover.c \
src/core/or/protover_rust.c \
@@ -238,6 +239,8 @@ noinst_HEADERS += \
src/core/or/listener_connection_st.h \
src/core/or/onion.h \
src/core/or/or.h \
+ src/core/or/orconn_event.h \
+ src/core/or/orconn_event_sys.h \
src/core/or/or_circuit_st.h \
src/core/or/or_connection_st.h \
src/core/or/or_handshake_certs_st.h \
diff --git a/src/core/mainloop/connection.c b/src/core/mainloop/connection.c
index 601c872c9..6cc612270 100644
--- a/src/core/mainloop/connection.c
+++ b/src/core/mainloop/connection.c
@@ -1875,7 +1875,7 @@ connection_init_accepted_conn(connection_t *conn,
/* Initiate Extended ORPort authentication. */
return connection_ext_or_start_auth(TO_OR_CONN(conn));
case CONN_TYPE_OR:
- control_event_or_conn_status(TO_OR_CONN(conn), OR_CONN_EVENT_NEW, 0);
+ connection_or_event_status(TO_OR_CONN(conn), OR_CONN_EVENT_NEW, 0);
rv = connection_tls_start_handshake(TO_OR_CONN(conn), 1);
if (rv < 0) {
connection_or_close_for_error(TO_OR_CONN(conn), 0);
diff --git a/src/core/or/connection_or.c b/src/core/or/connection_or.c
index 04ab4fe4a..a12ea55c4 100644
--- a/src/core/or/connection_or.c
+++ b/src/core/or/connection_or.c
@@ -29,6 +29,7 @@
*/
#define TOR_CHANNEL_INTERNAL_
#define CONNECTION_OR_PRIVATE
+#define ORCONN_EVENT_PRIVATE
#include "core/or/channel.h"
#include "core/or/channeltls.h"
#include "core/or/circuitbuild.h"
@@ -79,6 +80,8 @@
#include "lib/tls/tortls.h"
#include "lib/tls/x509.h"
+#include "core/or/orconn_event.h"
+
static int connection_tls_finish_handshake(or_connection_t *conn);
static int connection_or_launch_v3_or_handshake(or_connection_t *conn);
static int connection_or_process_cells_from_inbuf(or_connection_t *conn);
@@ -401,6 +404,49 @@ connection_or_report_broken_states(int severity, int domain)
smartlist_free(items);
}
+/**
+ * Helper function to publish an OR connection status event
+ *
+ * Publishes a messages to subscribers of ORCONN messages, and sends
+ * the control event.
+ **/
+void
+connection_or_event_status(or_connection_t *conn, or_conn_status_event_t tp,
+ int reason)
+{
+ orconn_event_msg_t msg;
+
+ msg.type = ORCONN_MSGTYPE_STATUS;
+ msg.u.status.gid = conn->base_.global_identifier;
+ msg.u.status.status = tp;
+ msg.u.status.reason = reason;
+ orconn_event_publish(&msg);
+ control_event_or_conn_status(conn, tp, reason);
+}
+
+/**
+ * Helper function to publish a state change message
+ *
+ * connection_or_change_state() calls this to notify subscribers about
+ * a change of an OR connection state.
+ **/
+static void
+connection_or_state_publish(const or_connection_t *conn, uint8_t state)
+{
+ orconn_event_msg_t msg;
+
+ msg.type = ORCONN_MSGTYPE_STATE;
+ msg.u.state.gid = conn->base_.global_identifier;
+ msg.u.state.proxy_type = conn->proxy_type;
+ msg.u.state.state = state;
+ if (conn->chan) {
+ msg.u.state.chan = TLS_CHAN_TO_BASE(conn->chan)->global_identifier;
+ } else {
+ msg.u.state.chan = 0;
+ }
+ orconn_event_publish(&msg);
+}
+
/** Call this to change or_connection_t states, so the owning channel_tls_t can
* be notified.
*/
@@ -412,6 +458,7 @@ connection_or_change_state(or_connection_t *conn, uint8_t state)
conn->base_.state = state;
+ connection_or_state_publish(conn, state);
if (conn->chan)
channel_tls_handle_state_change_on_orconn(conn->chan, conn, state);
}
@@ -755,8 +802,8 @@ connection_or_about_to_close(or_connection_t *or_conn)
entry_guard_chan_failed(TLS_CHAN_TO_BASE(or_conn->chan));
if (conn->state >= OR_CONN_STATE_TLS_HANDSHAKING) {
int reason = tls_error_to_orconn_end_reason(or_conn->tls_error);
- control_event_or_conn_status(or_conn, OR_CONN_EVENT_FAILED,
- reason);
+ connection_or_event_status(or_conn, OR_CONN_EVENT_FAILED,
+ reason);
if (!authdir_mode_tests_reachability(options))
control_event_bootstrap_prob_or(
orconn_end_reason_to_control_string(reason),
@@ -766,10 +813,10 @@ connection_or_about_to_close(or_connection_t *or_conn)
} else if (conn->hold_open_until_flushed) {
/* We only set hold_open_until_flushed when we're intentionally
* closing a connection. */
- control_event_or_conn_status(or_conn, OR_CONN_EVENT_CLOSED,
+ connection_or_event_status(or_conn, OR_CONN_EVENT_CLOSED,
tls_error_to_orconn_end_reason(or_conn->tls_error));
} else if (!tor_digest_is_zero(or_conn->identity_digest)) {
- control_event_or_conn_status(or_conn, OR_CONN_EVENT_CLOSED,
+ connection_or_event_status(or_conn, OR_CONN_EVENT_CLOSED,
tls_error_to_orconn_end_reason(or_conn->tls_error));
}
}
@@ -1361,7 +1408,7 @@ void
connection_or_connect_failed(or_connection_t *conn,
int reason, const char *msg)
{
- control_event_or_conn_status(conn, OR_CONN_EVENT_FAILED, reason);
+ connection_or_event_status(conn, OR_CONN_EVENT_FAILED, reason);
if (!authdir_mode_tests_reachability(get_options()))
control_event_bootstrap_prob_or(msg, reason, conn);
note_or_connect_failed(conn);
@@ -1468,9 +1515,6 @@ connection_or_connect, (const tor_addr_t *_addr, uint16_t port,
return NULL;
}
- connection_or_change_state(conn, OR_CONN_STATE_CONNECTING);
- control_event_or_conn_status(conn, OR_CONN_EVENT_LAUNCHED, 0);
-
conn->is_outgoing = 1;
/* If we are using a proxy server, find it and use it. */
@@ -1482,7 +1526,14 @@ connection_or_connect, (const tor_addr_t *_addr, uint16_t port,
port = proxy_port;
conn->base_.proxy_state = PROXY_INFANT;
}
+ connection_or_change_state(conn, OR_CONN_STATE_CONNECTING);
+ connection_or_event_status(conn, OR_CONN_EVENT_LAUNCHED, 0);
} else {
+ /* This duplication of state change calls is necessary in case we
+ * run into an error condition below */
+ connection_or_change_state(conn, OR_CONN_STATE_CONNECTING);
+ connection_or_event_status(conn, OR_CONN_EVENT_LAUNCHED, 0);
+
/* get_proxy_addrport() might fail if we have a Bridge line that
references a transport, but no ClientTransportPlugin lines
defining its transport proxy. If this is the case, let's try to
@@ -1978,8 +2029,8 @@ connection_or_client_learned_peer_id(or_connection_t *conn,
/* Tell the new guard API about the channel failure */
entry_guard_chan_failed(TLS_CHAN_TO_BASE(conn->chan));
- control_event_or_conn_status(conn, OR_CONN_EVENT_FAILED,
- END_OR_CONN_REASON_OR_IDENTITY);
+ connection_or_event_status(conn, OR_CONN_EVENT_FAILED,
+ END_OR_CONN_REASON_OR_IDENTITY);
if (!authdir_mode_tests_reachability(options))
control_event_bootstrap_prob_or(
"Unexpected identity in router certificate",
@@ -2219,7 +2270,7 @@ int
connection_or_set_state_open(or_connection_t *conn)
{
connection_or_change_state(conn, OR_CONN_STATE_OPEN);
- control_event_or_conn_status(conn, OR_CONN_EVENT_CONNECTED, 0);
+ connection_or_event_status(conn, OR_CONN_EVENT_CONNECTED, 0);
/* Link protocol 3 appeared in Tor 0.2.3.6-alpha, so any connection
* that uses an earlier link protocol should not be treated as a relay. */
diff --git a/src/core/or/connection_or.h b/src/core/or/connection_or.h
index d4bcdd93e..5f4856d51 100644
--- a/src/core/or/connection_or.h
+++ b/src/core/or/connection_or.h
@@ -17,32 +17,7 @@ struct ed25519_keypair_t;
or_connection_t *TO_OR_CONN(connection_t *);
-#define OR_CONN_STATE_MIN_ 1
-/** State for a connection to an OR: waiting for connect() to finish. */
-#define OR_CONN_STATE_CONNECTING 1
-/** State for a connection to an OR: waiting for proxy handshake to complete */
-#define OR_CONN_STATE_PROXY_HANDSHAKING 2
-/** State for an OR connection client: SSL is handshaking, not done
- * yet. */
-#define OR_CONN_STATE_TLS_HANDSHAKING 3
-/** State for a connection to an OR: We're doing a second SSL handshake for
- * renegotiation purposes. (V2 handshake only.) */
-#define OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING 4
-/** State for a connection at an OR: We're waiting for the client to
- * renegotiate (to indicate a v2 handshake) or send a versions cell (to
- * indicate a v3 handshake) */
-#define OR_CONN_STATE_TLS_SERVER_RENEGOTIATING 5
-/** State for an OR connection: We're done with our SSL handshake, we've done
- * renegotiation, but we haven't yet negotiated link protocol versions and
- * sent a netinfo cell. */
-#define OR_CONN_STATE_OR_HANDSHAKING_V2 6
-/** State for an OR connection: We're done with our SSL handshake, but we
- * haven't yet negotiated link protocol versions, done a V3 handshake, and
- * sent a netinfo cell. */
-#define OR_CONN_STATE_OR_HANDSHAKING_V3 7
-/** State for an OR connection: Ready to send/receive cells. */
-#define OR_CONN_STATE_OPEN 8
-#define OR_CONN_STATE_MAX_ 8
+#include "core/or/orconn_event.h"
void connection_or_clear_identity(or_connection_t *conn);
void connection_or_clear_identity_map(void);
@@ -81,6 +56,9 @@ MOCK_DECL(void,connection_or_close_for_error,
void connection_or_report_broken_states(int severity, int domain);
+void connection_or_event_status(or_connection_t *conn,
+ or_conn_status_event_t tp, int reason);
+
MOCK_DECL(int,connection_tls_start_handshake,(or_connection_t *conn,
int receiving));
int connection_tls_continue_handshake(or_connection_t *conn);
diff --git a/src/core/or/orconn_event.c b/src/core/or/orconn_event.c
new file mode 100644
index 000000000..11f5ed966
--- /dev/null
+++ b/src/core/or/orconn_event.c
@@ -0,0 +1,81 @@
+/* Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file orconn_event.c
+ * \brief Publish state change messages for OR connections
+ *
+ * Implements a basic publish-subscribe framework for messages about
+ * the state of OR connections. The publisher calls the subscriber
+ * callback functions synchronously.
+ *
+ * Although the synchronous calls might not simplify the call graph,
+ * this approach improves data isolation because the publisher doesn't
+ * need knowledge about the internals of subscribing subsystems. It
+ * also avoids race conditions that might occur in asynchronous
+ * frameworks.
+ **/
+
+#include "core/or/or.h"
+#include "lib/subsys/subsys.h"
+
+#define ORCONN_EVENT_PRIVATE
+#include "core/or/orconn_event.h"
+#include "core/or/orconn_event_sys.h"
+
+/** List of subscribers */
+static smartlist_t *orconn_event_rcvrs;
+
+/** Initialize subscriber list */
+static int
+orconn_event_init(void)
+{
+ orconn_event_rcvrs = smartlist_new();
+ return 0;
+}
+
+/** Free subscriber list */
+static void
+orconn_event_fini(void)
+{
+ smartlist_free(orconn_event_rcvrs);
+}
+
+/**
+ * Subscribe to messages about OR connection events
+ *
+ * Register a callback function to receive messages about ORCONNs.
+ * The publisher calls this function synchronously.
+ **/
+void
+orconn_event_subscribe(orconn_event_rcvr_t fn)
+{
+ tor_assert(fn);
+ /* Don't duplicate subscriptions. */
+ if (smartlist_contains(orconn_event_rcvrs, fn))
+ return;
+
+ smartlist_add(orconn_event_rcvrs, fn);
+}
+
+/**
+ * Publish a message about OR connection events
+ *
+ * This calls the subscriber receiver function synchronously.
+ **/
+void
+orconn_event_publish(const orconn_event_msg_t *msg)
+{
+ SMARTLIST_FOREACH_BEGIN(orconn_event_rcvrs, orconn_event_rcvr_t, fn) {
+ tor_assert(fn);
+ (*fn)(msg);
+ } SMARTLIST_FOREACH_END(fn);
+}
+
+const subsys_fns_t sys_orconn_event = {
+ .name = "orconn_event",
+ .supported = true,
+ .level = -40,
+ .initialize = orconn_event_init,
+ .shutdown = orconn_event_fini,
+};
diff --git a/src/core/or/orconn_event.h b/src/core/or/orconn_event.h
new file mode 100644
index 000000000..4c999e53b
--- /dev/null
+++ b/src/core/or/orconn_event.h
@@ -0,0 +1,120 @@
+/* Copyright (c) 2001 Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file orconn_event.h
+ * \brief Header file for orconn_event.c
+ *
+ * The OR_CONN_STATE_* symbols are here to make it easier for
+ * subscribers to make decisions based on the messages that they
+ * receive.
+ **/
+
+#ifndef TOR_ORCONN_EVENT_H
+#define TOR_ORCONN_EVENT_H
+
+/**
+ * @name States of OR connections
+ *
+ * These must be in a partial ordering such that usually no OR
+ * connection will transition from a higher-numbered state to a
+ * lower-numbered one. Code such as bto_update_best() depends on this
+ * ordering to determine the best state it's seen so far.
+ * @{ */
+#define OR_CONN_STATE_MIN_ 1
+/** State for a connection to an OR: waiting for connect() to finish. */
+#define OR_CONN_STATE_CONNECTING 1
+/** State for a connection to an OR: waiting for proxy handshake to complete */
+#define OR_CONN_STATE_PROXY_HANDSHAKING 2
+/** State for an OR connection client: SSL is handshaking, not done
+ * yet. */
+#define OR_CONN_STATE_TLS_HANDSHAKING 3
+/** State for a connection to an OR: We're doing a second SSL handshake for
+ * renegotiation purposes. (V2 handshake only.) */
+#define OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING 4
+/** State for a connection at an OR: We're waiting for the client to
+ * renegotiate (to indicate a v2 handshake) or send a versions cell (to
+ * indicate a v3 handshake) */
+#define OR_CONN_STATE_TLS_SERVER_RENEGOTIATING 5
+/** State for an OR connection: We're done with our SSL handshake, we've done
+ * renegotiation, but we haven't yet negotiated link protocol versions and
+ * sent a netinfo cell. */
+#define OR_CONN_STATE_OR_HANDSHAKING_V2 6
+/** State for an OR connection: We're done with our SSL handshake, but we
+ * haven't yet negotiated link protocol versions, done a V3 handshake, and
+ * sent a netinfo cell. */
+#define OR_CONN_STATE_OR_HANDSHAKING_V3 7
+/** State for an OR connection: Ready to send/receive cells. */
+#define OR_CONN_STATE_OPEN 8
+#define OR_CONN_STATE_MAX_ 8
+/** @} */
+
+/** Used to indicate the type of an OR connection event passed to the
+ * controller. The various types are defined in control-spec.txt */
+typedef enum or_conn_status_event_t {
+ OR_CONN_EVENT_LAUNCHED = 0,
+ OR_CONN_EVENT_CONNECTED = 1,
+ OR_CONN_EVENT_FAILED = 2,
+ OR_CONN_EVENT_CLOSED = 3,
+ OR_CONN_EVENT_NEW = 4,
+} or_conn_status_event_t;
+
+/** Discriminant values for orconn event message */
+typedef enum orconn_msgtype_t {
+ ORCONN_MSGTYPE_STATE,
+ ORCONN_MSGTYPE_STATUS,
+} orconn_msgtype_t;
+
+/**
+ * Message for orconn state update
+ *
+ * This contains information about internal state changes of
+ * or_connection_t objects. The chan and proxy_type fields are
+ * additional information that a subscriber may need to make
+ * decisions.
+ **/
+typedef struct orconn_state_msg_t {
+ uint64_t gid; /**< connection's global ID */
+ uint64_t chan; /**< associated channel ID */
+ int proxy_type; /**< connection's proxy type */
+ uint8_t state; /**< new connection state */
+} orconn_state_msg_t;
+
+/**
+ * Message for orconn status event
+ *
+ * This contains information that ends up in ORCONN control protocol
+ * events.
+ **/
+typedef struct orconn_status_msg_t {
+ uint64_t gid; /**< connection's global ID */
+ int status; /**< or_conn_status_event_t */
+ int reason; /**< reason */
+} orconn_status_msg_t;
+
+/** Discriminated union for the actual message */
+typedef struct orconn_event_msg_t {
+ int type;
+ union {
+ orconn_state_msg_t state;
+ orconn_status_msg_t status;
+ } u;
+} orconn_event_msg_t;
+
+/**
+ * Receiver function pointer for OR subscribers
+ *
+ * This function gets called synchronously by the publisher.
+ **/
+typedef void (*orconn_event_rcvr_t)(const orconn_event_msg_t *);
+
+void orconn_event_subscribe(orconn_event_rcvr_t);
+
+#ifdef ORCONN_EVENT_PRIVATE
+void orconn_event_publish(const orconn_event_msg_t *);
+#endif
+
+#endif /* defined(TOR_ORCONN_EVENT_H) */
diff --git a/src/core/or/orconn_event_sys.h b/src/core/or/orconn_event_sys.h
new file mode 100644
index 000000000..763902338
--- /dev/null
+++ b/src/core/or/orconn_event_sys.h
@@ -0,0 +1,12 @@
+/* Copyright (c) 2007-2018, The Tor Project, Inc. */
+
+/**
+ * \file orconn_event_sys.h
+ * \brief Declare subsystem object for the OR connection event module.
+ **/
+#ifndef TOR_ORCONN_EVENT_SYS_H
+#define TOR_ORCONN_EVENT_SYS_H
+
+extern const struct subsys_fns_t sys_orconn_event;
+
+#endif /* defined(TOR_ORCONN_SYS_H) */
diff --git a/src/feature/control/control.h b/src/feature/control/control.h
index d78ce4d87..d3245fcaf 100644
--- a/src/feature/control/control.h
+++ b/src/feature/control/control.h
@@ -29,6 +29,8 @@ typedef enum circuit_status_minor_event_t {
CIRC_MINOR_EVENT_CANNIBALIZED,
} circuit_status_minor_event_t;
+#include "core/or/orconn_event.h"
+
/** Used to indicate the type of a stream event passed to the controller.
* The various types are defined in control-spec.txt */
typedef enum stream_status_event_t {
@@ -43,16 +45,6 @@ typedef enum stream_status_event_t {
STREAM_EVENT_REMAP = 8
} stream_status_event_t;
-/** Used to indicate the type of an OR connection event passed to the
- * controller. The various types are defined in control-spec.txt */
-typedef enum or_conn_status_event_t {
- OR_CONN_EVENT_LAUNCHED = 0,
- OR_CONN_EVENT_CONNECTED = 1,
- OR_CONN_EVENT_FAILED = 2,
- OR_CONN_EVENT_CLOSED = 3,
- OR_CONN_EVENT_NEW = 4,
-} or_conn_status_event_t;
-
/** Used to indicate the type of a buildtime event */
typedef enum buildtimeout_set_event_t {
BUILDTIMEOUT_SET_EVENT_COMPUTED = 0,
diff --git a/src/feature/relay/ext_orport.c b/src/feature/relay/ext_orport.c
index 3607bdede..0a649f274 100644
--- a/src/feature/relay/ext_orport.c
+++ b/src/feature/relay/ext_orport.c
@@ -90,7 +90,7 @@ connection_ext_or_transition(or_connection_t *conn)
conn->base_.type = CONN_TYPE_OR;
TO_CONN(conn)->state = 0; // set the state to a neutral value
- control_event_or_conn_status(conn, OR_CONN_EVENT_NEW, 0);
+ connection_or_event_status(conn, OR_CONN_EVENT_NEW, 0);
connection_tls_start_handshake(conn, 1);
}
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