tor/src/or/connection.c
David Goulet c05272783d dos: Track new and closed OR client connections
Implement a basic connection tracking that counts the number of concurrent
connections when they open and close.

This commit also adds the circuit creation mitigation data structure that will
be needed at later commit to keep track of the circuit rate.

Signed-off-by: David Goulet <dgoulet@torproject.org>
2018-01-30 09:18:15 -05:00

5166 lines
175 KiB
C

/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2016, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file connection.c
* \brief General high-level functions to handle reading and writing
* on connections.
*
* Each connection (ideally) represents a TLS connection, a TCP socket, a unix
* socket, or a UDP socket on which reads and writes can occur. (But see
* connection_edge.c for cases where connections can also represent streams
* that do not have a corresponding socket.)
*
* The module implements the abstract type, connection_t. The subtypes are:
* <ul>
* <li>listener_connection_t, implemented here in connection.c
* <li>dir_connection_t, implemented in directory.c
* <li>or_connection_t, implemented in connection_or.c
* <li>edge_connection_t, implemented in connection_edge.c, along with
* its subtype(s):
* <ul><li>entry_connection_t, also implemented in connection_edge.c
* </ul>
* <li>control_connection_t, implemented in control.c
* </ul>
*
* The base type implemented in this module is responsible for basic
* rate limiting, flow control, and marshalling bytes onto and off of the
* network (either directly or via TLS).
*
* Connections are registered with the main loop with connection_add(). As
* they become able to read or write register the fact with the event main
* loop by calling connection_watch_events(), connection_start_reading(), or
* connection_start_writing(). When they no longer want to read or write,
* they call connection_stop_reading() or connection_start_writing().
*
* To queue data to be written on a connection, call
* connection_write_to_buf(). When data arrives, the
* connection_process_inbuf() callback is invoked, which dispatches to a
* type-specific function (such as connection_edge_process_inbuf() for
* example). Connection types that need notice of when data has been written
* receive notification via connection_flushed_some() and
* connection_finished_flushing(). These functions all delegate to
* type-specific implementations.
*
* Additionally, beyond the core of connection_t, this module also implements:
* <ul>
* <li>Listeners, which wait for incoming sockets and launch connections
* <li>Outgoing SOCKS proxy support
* <li>Outgoing HTTP proxy support
* <li>An out-of-sockets handler for dealing with socket exhaustion
* </ul>
**/
#define CONNECTION_PRIVATE
#include "or.h"
#include "buffers.h"
/*
* Define this so we get channel internal functions, since we're implementing
* part of a subclass (channel_tls_t).
*/
#define TOR_CHANNEL_INTERNAL_
#define CONNECTION_PRIVATE
#include "backtrace.h"
#include "channel.h"
#include "channeltls.h"
#include "circuitbuild.h"
#include "circuitlist.h"
#include "circuituse.h"
#include "config.h"
#include "connection.h"
#include "connection_edge.h"
#include "connection_or.h"
#include "control.h"
#include "directory.h"
#include "dirserv.h"
#include "dns.h"
#include "dnsserv.h"
#include "dos.h"
#include "entrynodes.h"
#include "ext_orport.h"
#include "geoip.h"
#include "main.h"
#include "nodelist.h"
#include "policies.h"
#include "reasons.h"
#include "relay.h"
#include "rendclient.h"
#include "rendcommon.h"
#include "rephist.h"
#include "router.h"
#include "routerlist.h"
#include "transports.h"
#include "routerparse.h"
#include "sandbox.h"
#include "transports.h"
#ifdef HAVE_PWD_H
#include <pwd.h>
#endif
#ifdef HAVE_SYS_UN_H
#include <sys/socket.h>
#include <sys/un.h>
#endif
static connection_t *connection_listener_new(
const struct sockaddr *listensockaddr,
socklen_t listensocklen, int type,
const char *address,
const port_cfg_t *portcfg);
static void connection_init(time_t now, connection_t *conn, int type,
int socket_family);
static int connection_init_accepted_conn(connection_t *conn,
const listener_connection_t *listener);
static int connection_handle_listener_read(connection_t *conn, int new_type);
static int connection_bucket_should_increase(int bucket,
or_connection_t *conn);
static int connection_finished_flushing(connection_t *conn);
static int connection_flushed_some(connection_t *conn);
static int connection_finished_connecting(connection_t *conn);
static int connection_reached_eof(connection_t *conn);
static int connection_read_to_buf(connection_t *conn, ssize_t *max_to_read,
int *socket_error);
static int connection_process_inbuf(connection_t *conn, int package_partial);
static void client_check_address_changed(tor_socket_t sock);
static void set_constrained_socket_buffers(tor_socket_t sock, int size);
static const char *connection_proxy_state_to_string(int state);
static int connection_read_https_proxy_response(connection_t *conn);
static void connection_send_socks5_connect(connection_t *conn);
static const char *proxy_type_to_string(int proxy_type);
static int get_proxy_type(void);
/** The last addresses that our network interface seemed to have been
* binding to. We use this as one way to detect when our IP changes.
*
* XXXX+ We should really use the entire list of interfaces here.
**/
static tor_addr_t *last_interface_ipv4 = NULL;
/* DOCDOC last_interface_ipv6 */
static tor_addr_t *last_interface_ipv6 = NULL;
/** A list of tor_addr_t for addresses we've used in outgoing connections.
* Used to detect IP address changes. */
static smartlist_t *outgoing_addrs = NULL;
#define CASE_ANY_LISTENER_TYPE \
case CONN_TYPE_OR_LISTENER: \
case CONN_TYPE_EXT_OR_LISTENER: \
case CONN_TYPE_AP_LISTENER: \
case CONN_TYPE_DIR_LISTENER: \
case CONN_TYPE_CONTROL_LISTENER: \
case CONN_TYPE_AP_TRANS_LISTENER: \
case CONN_TYPE_AP_NATD_LISTENER: \
case CONN_TYPE_AP_DNS_LISTENER
/**************************************************************/
/**
* Return the human-readable name for the connection type <b>type</b>
*/
const char *
conn_type_to_string(int type)
{
static char buf[64];
switch (type) {
case CONN_TYPE_OR_LISTENER: return "OR listener";
case CONN_TYPE_OR: return "OR";
case CONN_TYPE_EXIT: return "Exit";
case CONN_TYPE_AP_LISTENER: return "Socks listener";
case CONN_TYPE_AP_TRANS_LISTENER:
return "Transparent pf/netfilter listener";
case CONN_TYPE_AP_NATD_LISTENER: return "Transparent natd listener";
case CONN_TYPE_AP_DNS_LISTENER: return "DNS listener";
case CONN_TYPE_AP: return "Socks";
case CONN_TYPE_DIR_LISTENER: return "Directory listener";
case CONN_TYPE_DIR: return "Directory";
case CONN_TYPE_CONTROL_LISTENER: return "Control listener";
case CONN_TYPE_CONTROL: return "Control";
case CONN_TYPE_EXT_OR: return "Extended OR";
case CONN_TYPE_EXT_OR_LISTENER: return "Extended OR listener";
default:
log_warn(LD_BUG, "unknown connection type %d", type);
tor_snprintf(buf, sizeof(buf), "unknown [%d]", type);
return buf;
}
}
/**
* Return the human-readable name for the connection state <b>state</b>
* for the connection type <b>type</b>
*/
const char *
conn_state_to_string(int type, int state)
{
static char buf[96];
switch (type) {
CASE_ANY_LISTENER_TYPE:
if (state == LISTENER_STATE_READY)
return "ready";
break;
case CONN_TYPE_OR:
switch (state) {
case OR_CONN_STATE_CONNECTING: return "connect()ing";
case OR_CONN_STATE_PROXY_HANDSHAKING: return "handshaking (proxy)";
case OR_CONN_STATE_TLS_HANDSHAKING: return "handshaking (TLS)";
case OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING:
return "renegotiating (TLS, v2 handshake)";
case OR_CONN_STATE_TLS_SERVER_RENEGOTIATING:
return "waiting for renegotiation or V3 handshake";
case OR_CONN_STATE_OR_HANDSHAKING_V2:
return "handshaking (Tor, v2 handshake)";
case OR_CONN_STATE_OR_HANDSHAKING_V3:
return "handshaking (Tor, v3 handshake)";
case OR_CONN_STATE_OPEN: return "open";
}
break;
case CONN_TYPE_EXT_OR:
switch (state) {
case EXT_OR_CONN_STATE_AUTH_WAIT_AUTH_TYPE:
return "waiting for authentication type";
case EXT_OR_CONN_STATE_AUTH_WAIT_CLIENT_NONCE:
return "waiting for client nonce";
case EXT_OR_CONN_STATE_AUTH_WAIT_CLIENT_HASH:
return "waiting for client hash";
case EXT_OR_CONN_STATE_OPEN: return "open";
case EXT_OR_CONN_STATE_FLUSHING: return "flushing final OKAY";
}
break;
case CONN_TYPE_EXIT:
switch (state) {
case EXIT_CONN_STATE_RESOLVING: return "waiting for dest info";
case EXIT_CONN_STATE_CONNECTING: return "connecting";
case EXIT_CONN_STATE_OPEN: return "open";
case EXIT_CONN_STATE_RESOLVEFAILED: return "resolve failed";
}
break;
case CONN_TYPE_AP:
switch (state) {
case AP_CONN_STATE_SOCKS_WAIT: return "waiting for socks info";
case AP_CONN_STATE_NATD_WAIT: return "waiting for natd dest info";
case AP_CONN_STATE_RENDDESC_WAIT: return "waiting for rendezvous desc";
case AP_CONN_STATE_CONTROLLER_WAIT: return "waiting for controller";
case AP_CONN_STATE_CIRCUIT_WAIT: return "waiting for circuit";
case AP_CONN_STATE_CONNECT_WAIT: return "waiting for connect response";
case AP_CONN_STATE_RESOLVE_WAIT: return "waiting for resolve response";
case AP_CONN_STATE_OPEN: return "open";
}
break;
case CONN_TYPE_DIR:
switch (state) {
case DIR_CONN_STATE_CONNECTING: return "connecting";
case DIR_CONN_STATE_CLIENT_SENDING: return "client sending";
case DIR_CONN_STATE_CLIENT_READING: return "client reading";
case DIR_CONN_STATE_CLIENT_FINISHED: return "client finished";
case DIR_CONN_STATE_SERVER_COMMAND_WAIT: return "waiting for command";
case DIR_CONN_STATE_SERVER_WRITING: return "writing";
}
break;
case CONN_TYPE_CONTROL:
switch (state) {
case CONTROL_CONN_STATE_OPEN: return "open (protocol v1)";
case CONTROL_CONN_STATE_NEEDAUTH:
return "waiting for authentication (protocol v1)";
}
break;
}
log_warn(LD_BUG, "unknown connection state %d (type %d)", state, type);
tor_snprintf(buf, sizeof(buf),
"unknown state [%d] on unknown [%s] connection",
state, conn_type_to_string(type));
return buf;
}
/** Allocate and return a new dir_connection_t, initialized as by
* connection_init(). */
dir_connection_t *
dir_connection_new(int socket_family)
{
dir_connection_t *dir_conn = tor_malloc_zero(sizeof(dir_connection_t));
connection_init(time(NULL), TO_CONN(dir_conn), CONN_TYPE_DIR, socket_family);
return dir_conn;
}
/** Allocate and return a new or_connection_t, initialized as by
* connection_init().
*
* Initialize active_circuit_pqueue.
*
* Set active_circuit_pqueue_last_recalibrated to current cell_ewma tick.
*/
or_connection_t *
or_connection_new(int type, int socket_family)
{
or_connection_t *or_conn = tor_malloc_zero(sizeof(or_connection_t));
time_t now = time(NULL);
tor_assert(type == CONN_TYPE_OR || type == CONN_TYPE_EXT_OR);
connection_init(now, TO_CONN(or_conn), type, socket_family);
connection_or_set_canonical(or_conn, 0);
if (type == CONN_TYPE_EXT_OR)
connection_or_set_ext_or_identifier(or_conn);
return or_conn;
}
/** Allocate and return a new entry_connection_t, initialized as by
* connection_init().
*
* Allocate space to store the socks_request.
*/
entry_connection_t *
entry_connection_new(int type, int socket_family)
{
entry_connection_t *entry_conn = tor_malloc_zero(sizeof(entry_connection_t));
tor_assert(type == CONN_TYPE_AP);
connection_init(time(NULL), ENTRY_TO_CONN(entry_conn), type, socket_family);
entry_conn->socks_request = socks_request_new();
/* If this is coming from a listener, we'll set it up based on the listener
* in a little while. Otherwise, we're doing this as a linked connection
* of some kind, and we should set it up here based on the socket family */
if (socket_family == AF_INET)
entry_conn->entry_cfg.ipv4_traffic = 1;
else if (socket_family == AF_INET6)
entry_conn->entry_cfg.ipv6_traffic = 1;
else if (socket_family == AF_UNIX)
entry_conn->is_socks_socket = 1;
return entry_conn;
}
/** Allocate and return a new edge_connection_t, initialized as by
* connection_init(). */
edge_connection_t *
edge_connection_new(int type, int socket_family)
{
edge_connection_t *edge_conn = tor_malloc_zero(sizeof(edge_connection_t));
tor_assert(type == CONN_TYPE_EXIT);
connection_init(time(NULL), TO_CONN(edge_conn), type, socket_family);
return edge_conn;
}
/** Allocate and return a new control_connection_t, initialized as by
* connection_init(). */
control_connection_t *
control_connection_new(int socket_family)
{
control_connection_t *control_conn =
tor_malloc_zero(sizeof(control_connection_t));
connection_init(time(NULL),
TO_CONN(control_conn), CONN_TYPE_CONTROL, socket_family);
return control_conn;
}
/** Allocate and return a new listener_connection_t, initialized as by
* connection_init(). */
listener_connection_t *
listener_connection_new(int type, int socket_family)
{
listener_connection_t *listener_conn =
tor_malloc_zero(sizeof(listener_connection_t));
connection_init(time(NULL), TO_CONN(listener_conn), type, socket_family);
return listener_conn;
}
/** Allocate, initialize, and return a new connection_t subtype of <b>type</b>
* to make or receive connections of address family <b>socket_family</b>. The
* type should be one of the CONN_TYPE_* constants. */
connection_t *
connection_new(int type, int socket_family)
{
switch (type) {
case CONN_TYPE_OR:
case CONN_TYPE_EXT_OR:
return TO_CONN(or_connection_new(type, socket_family));
case CONN_TYPE_EXIT:
return TO_CONN(edge_connection_new(type, socket_family));
case CONN_TYPE_AP:
return ENTRY_TO_CONN(entry_connection_new(type, socket_family));
case CONN_TYPE_DIR:
return TO_CONN(dir_connection_new(socket_family));
case CONN_TYPE_CONTROL:
return TO_CONN(control_connection_new(socket_family));
CASE_ANY_LISTENER_TYPE:
return TO_CONN(listener_connection_new(type, socket_family));
default: {
connection_t *conn = tor_malloc_zero(sizeof(connection_t));
connection_init(time(NULL), conn, type, socket_family);
return conn;
}
}
}
/** Initializes conn. (you must call connection_add() to link it into the main
* array).
*
* Set conn-\>magic to the correct value.
*
* Set conn-\>type to <b>type</b>. Set conn-\>s and conn-\>conn_array_index to
* -1 to signify they are not yet assigned.
*
* Initialize conn's timestamps to now.
*/
static void
connection_init(time_t now, connection_t *conn, int type, int socket_family)
{
static uint64_t n_connections_allocated = 1;
switch (type) {
case CONN_TYPE_OR:
case CONN_TYPE_EXT_OR:
conn->magic = OR_CONNECTION_MAGIC;
break;
case CONN_TYPE_EXIT:
conn->magic = EDGE_CONNECTION_MAGIC;
break;
case CONN_TYPE_AP:
conn->magic = ENTRY_CONNECTION_MAGIC;
break;
case CONN_TYPE_DIR:
conn->magic = DIR_CONNECTION_MAGIC;
break;
case CONN_TYPE_CONTROL:
conn->magic = CONTROL_CONNECTION_MAGIC;
break;
CASE_ANY_LISTENER_TYPE:
conn->magic = LISTENER_CONNECTION_MAGIC;
break;
default:
conn->magic = BASE_CONNECTION_MAGIC;
break;
}
conn->s = TOR_INVALID_SOCKET; /* give it a default of 'not used' */
conn->conn_array_index = -1; /* also default to 'not used' */
conn->global_identifier = n_connections_allocated++;
conn->type = type;
conn->socket_family = socket_family;
if (!connection_is_listener(conn)) {
/* listeners never use their buf */
conn->inbuf = buf_new();
conn->outbuf = buf_new();
}
conn->timestamp_created = now;
conn->timestamp_lastread = now;
conn->timestamp_lastwritten = now;
}
/** Create a link between <b>conn_a</b> and <b>conn_b</b>. */
void
connection_link_connections(connection_t *conn_a, connection_t *conn_b)
{
tor_assert(! SOCKET_OK(conn_a->s));
tor_assert(! SOCKET_OK(conn_b->s));
conn_a->linked = 1;
conn_b->linked = 1;
conn_a->linked_conn = conn_b;
conn_b->linked_conn = conn_a;
}
/** Return true iff the provided connection listener type supports AF_UNIX
* sockets. */
int
conn_listener_type_supports_af_unix(int type)
{
/* For now only control ports or SOCKS ports can be Unix domain sockets
* and listeners at the same time */
switch (type) {
case CONN_TYPE_CONTROL_LISTENER:
case CONN_TYPE_AP_LISTENER:
return 1;
default:
return 0;
}
}
/** Deallocate memory used by <b>conn</b>. Deallocate its buffers if
* necessary, close its socket if necessary, and mark the directory as dirty
* if <b>conn</b> is an OR or OP connection.
*/
STATIC void
connection_free_(connection_t *conn)
{
void *mem;
size_t memlen;
if (!conn)
return;
switch (conn->type) {
case CONN_TYPE_OR:
case CONN_TYPE_EXT_OR:
tor_assert(conn->magic == OR_CONNECTION_MAGIC);
mem = TO_OR_CONN(conn);
memlen = sizeof(or_connection_t);
break;
case CONN_TYPE_AP:
tor_assert(conn->magic == ENTRY_CONNECTION_MAGIC);
mem = TO_ENTRY_CONN(conn);
memlen = sizeof(entry_connection_t);
break;
case CONN_TYPE_EXIT:
tor_assert(conn->magic == EDGE_CONNECTION_MAGIC);
mem = TO_EDGE_CONN(conn);
memlen = sizeof(edge_connection_t);
break;
case CONN_TYPE_DIR:
tor_assert(conn->magic == DIR_CONNECTION_MAGIC);
mem = TO_DIR_CONN(conn);
memlen = sizeof(dir_connection_t);
break;
case CONN_TYPE_CONTROL:
tor_assert(conn->magic == CONTROL_CONNECTION_MAGIC);
mem = TO_CONTROL_CONN(conn);
memlen = sizeof(control_connection_t);
break;
CASE_ANY_LISTENER_TYPE:
tor_assert(conn->magic == LISTENER_CONNECTION_MAGIC);
mem = TO_LISTENER_CONN(conn);
memlen = sizeof(listener_connection_t);
break;
default:
tor_assert(conn->magic == BASE_CONNECTION_MAGIC);
mem = conn;
memlen = sizeof(connection_t);
break;
}
if (conn->linked) {
log_info(LD_GENERAL, "Freeing linked %s connection [%s] with %d "
"bytes on inbuf, %d on outbuf.",
conn_type_to_string(conn->type),
conn_state_to_string(conn->type, conn->state),
(int)connection_get_inbuf_len(conn),
(int)connection_get_outbuf_len(conn));
}
if (!connection_is_listener(conn)) {
buf_free(conn->inbuf);
buf_free(conn->outbuf);
} else {
if (conn->socket_family == AF_UNIX) {
/* For now only control and SOCKS ports can be Unix domain sockets
* and listeners at the same time */
tor_assert(conn_listener_type_supports_af_unix(conn->type));
if (unlink(conn->address) < 0 && errno != ENOENT) {
log_warn(LD_NET, "Could not unlink %s: %s", conn->address,
strerror(errno));
}
}
}
tor_free(conn->address);
if (connection_speaks_cells(conn)) {
or_connection_t *or_conn = TO_OR_CONN(conn);
tor_tls_free(or_conn->tls);
or_conn->tls = NULL;
or_handshake_state_free(or_conn->handshake_state);
or_conn->handshake_state = NULL;
tor_free(or_conn->nickname);
if (or_conn->chan) {
/* Owww, this shouldn't happen, but... */
log_info(LD_CHANNEL,
"Freeing orconn at %p, saw channel %p with ID "
U64_FORMAT " left un-NULLed",
or_conn, TLS_CHAN_TO_BASE(or_conn->chan),
U64_PRINTF_ARG(
TLS_CHAN_TO_BASE(or_conn->chan)->global_identifier));
if (!CHANNEL_FINISHED(TLS_CHAN_TO_BASE(or_conn->chan))) {
channel_close_for_error(TLS_CHAN_TO_BASE(or_conn->chan));
}
or_conn->chan->conn = NULL;
or_conn->chan = NULL;
}
}
if (conn->type == CONN_TYPE_AP) {
entry_connection_t *entry_conn = TO_ENTRY_CONN(conn);
tor_free(entry_conn->chosen_exit_name);
tor_free(entry_conn->original_dest_address);
if (entry_conn->socks_request)
socks_request_free(entry_conn->socks_request);
if (entry_conn->pending_optimistic_data) {
buf_free(entry_conn->pending_optimistic_data);
}
if (entry_conn->sending_optimistic_data) {
buf_free(entry_conn->sending_optimistic_data);
}
}
if (CONN_IS_EDGE(conn)) {
rend_data_free(TO_EDGE_CONN(conn)->rend_data);
}
if (conn->type == CONN_TYPE_CONTROL) {
control_connection_t *control_conn = TO_CONTROL_CONN(conn);
tor_free(control_conn->safecookie_client_hash);
tor_free(control_conn->incoming_cmd);
if (control_conn->ephemeral_onion_services) {
SMARTLIST_FOREACH(control_conn->ephemeral_onion_services, char *, cp, {
memwipe(cp, 0, strlen(cp));
tor_free(cp);
});
smartlist_free(control_conn->ephemeral_onion_services);
}
}
/* Probably already freed by connection_free. */
tor_event_free(conn->read_event);
tor_event_free(conn->write_event);
conn->read_event = conn->write_event = NULL;
if (conn->type == CONN_TYPE_DIR) {
dir_connection_t *dir_conn = TO_DIR_CONN(conn);
tor_free(dir_conn->requested_resource);
tor_zlib_free(dir_conn->zlib_state);
if (dir_conn->fingerprint_stack) {
SMARTLIST_FOREACH(dir_conn->fingerprint_stack, char *, cp, tor_free(cp));
smartlist_free(dir_conn->fingerprint_stack);
}
cached_dir_decref(dir_conn->cached_dir);
rend_data_free(dir_conn->rend_data);
}
if (SOCKET_OK(conn->s)) {
log_debug(LD_NET,"closing fd %d.",(int)conn->s);
tor_close_socket(conn->s);
conn->s = TOR_INVALID_SOCKET;
}
if (conn->type == CONN_TYPE_OR &&
!tor_digest_is_zero(TO_OR_CONN(conn)->identity_digest)) {
log_warn(LD_BUG, "called on OR conn with non-zeroed identity_digest");
connection_or_remove_from_identity_map(TO_OR_CONN(conn));
}
if (conn->type == CONN_TYPE_OR || conn->type == CONN_TYPE_EXT_OR) {
connection_or_remove_from_ext_or_id_map(TO_OR_CONN(conn));
tor_free(TO_OR_CONN(conn)->ext_or_conn_id);
tor_free(TO_OR_CONN(conn)->ext_or_auth_correct_client_hash);
tor_free(TO_OR_CONN(conn)->ext_or_transport);
}
memwipe(mem, 0xCC, memlen); /* poison memory */
tor_free(mem);
}
/** Make sure <b>conn</b> isn't in any of the global conn lists; then free it.
*/
MOCK_IMPL(void,
connection_free,(connection_t *conn))
{
if (!conn)
return;
tor_assert(!connection_is_on_closeable_list(conn));
tor_assert(!connection_in_array(conn));
if (BUG(conn->linked_conn)) {
conn->linked_conn->linked_conn = NULL;
if (! conn->linked_conn->marked_for_close &&
conn->linked_conn->reading_from_linked_conn)
connection_start_reading(conn->linked_conn);
conn->linked_conn = NULL;
}
if (connection_speaks_cells(conn)) {
if (!tor_digest_is_zero(TO_OR_CONN(conn)->identity_digest)) {
connection_or_remove_from_identity_map(TO_OR_CONN(conn));
}
}
if (conn->type == CONN_TYPE_CONTROL) {
connection_control_closed(TO_CONTROL_CONN(conn));
}
#if 1
/* DEBUGGING */
if (conn->type == CONN_TYPE_AP) {
connection_ap_warn_and_unmark_if_pending_circ(TO_ENTRY_CONN(conn),
"connection_free");
}
#endif
/* Notify the circuit creation DoS mitigation subsystem that an OR client
* connection has been closed. And only do that if we track it. */
if (conn->type == CONN_TYPE_OR) {
dos_close_client_conn(TO_OR_CONN(conn));
}
connection_unregister_events(conn);
connection_free_(conn);
}
/**
* Called when we're about to finally unlink and free a connection:
* perform necessary accounting and cleanup
* - Directory conns that failed to fetch a rendezvous descriptor
* need to inform pending rendezvous streams.
* - OR conns need to call rep_hist_note_*() to record status.
* - AP conns need to send a socks reject if necessary.
* - Exit conns need to call connection_dns_remove() if necessary.
* - AP and Exit conns need to send an end cell if they can.
* - DNS conns need to fail any resolves that are pending on them.
* - OR and edge connections need to be unlinked from circuits.
*/
void
connection_about_to_close_connection(connection_t *conn)
{
tor_assert(conn->marked_for_close);
switch (conn->type) {
case CONN_TYPE_DIR:
connection_dir_about_to_close(TO_DIR_CONN(conn));
break;
case CONN_TYPE_OR:
case CONN_TYPE_EXT_OR:
connection_or_about_to_close(TO_OR_CONN(conn));
break;
case CONN_TYPE_AP:
connection_ap_about_to_close(TO_ENTRY_CONN(conn));
break;
case CONN_TYPE_EXIT:
connection_exit_about_to_close(TO_EDGE_CONN(conn));
break;
}
}
/** Return true iff connection_close_immediate() has been called on this
* connection. */
#define CONN_IS_CLOSED(c) \
((c)->linked ? ((c)->linked_conn_is_closed) : (! SOCKET_OK(c->s)))
/** Close the underlying socket for <b>conn</b>, so we don't try to
* flush it. Must be used in conjunction with (right before)
* connection_mark_for_close().
*/
void
connection_close_immediate(connection_t *conn)
{
assert_connection_ok(conn,0);
if (CONN_IS_CLOSED(conn)) {
log_err(LD_BUG,"Attempt to close already-closed connection.");
tor_fragile_assert();
return;
}
if (conn->outbuf_flushlen) {
log_info(LD_NET,"fd %d, type %s, state %s, %d bytes on outbuf.",
(int)conn->s, conn_type_to_string(conn->type),
conn_state_to_string(conn->type, conn->state),
(int)conn->outbuf_flushlen);
}
connection_unregister_events(conn);
/* Prevent the event from getting unblocked. */
conn->read_blocked_on_bw =
conn->write_blocked_on_bw = 0;
if (SOCKET_OK(conn->s))
tor_close_socket(conn->s);
conn->s = TOR_INVALID_SOCKET;
if (conn->linked)
conn->linked_conn_is_closed = 1;
if (conn->outbuf)
buf_clear(conn->outbuf);
conn->outbuf_flushlen = 0;
}
/** Mark <b>conn</b> to be closed next time we loop through
* conn_close_if_marked() in main.c. */
void
connection_mark_for_close_(connection_t *conn, int line, const char *file)
{
assert_connection_ok(conn,0);
tor_assert(line);
tor_assert(line < 1<<16); /* marked_for_close can only fit a uint16_t. */
tor_assert(file);
if (conn->type == CONN_TYPE_OR) {
/*
* An or_connection should have been closed through one of the channel-
* aware functions in connection_or.c. We'll assume this is an error
* close and do that, and log a bug warning.
*/
log_warn(LD_CHANNEL | LD_BUG,
"Something tried to close an or_connection_t without going "
"through channels at %s:%d",
file, line);
connection_or_close_for_error(TO_OR_CONN(conn), 0);
} else {
/* Pass it down to the real function */
connection_mark_for_close_internal_(conn, line, file);
}
}
/** Mark <b>conn</b> to be closed next time we loop through
* conn_close_if_marked() in main.c; the _internal version bypasses the
* CONN_TYPE_OR checks; this should be called when you either are sure that
* if this is an or_connection_t the controlling channel has been notified
* (e.g. with connection_or_notify_error()), or you actually are the
* connection_or_close_for_error() or connection_or_close_normally function.
* For all other cases, use connection_mark_and_flush() instead, which
* checks for or_connection_t properly, instead. See below.
*/
MOCK_IMPL(void,
connection_mark_for_close_internal_, (connection_t *conn,
int line, const char *file))
{
assert_connection_ok(conn,0);
tor_assert(line);
tor_assert(line < 1<<16); /* marked_for_close can only fit a uint16_t. */
tor_assert(file);
if (conn->marked_for_close) {
log_warn(LD_BUG,"Duplicate call to connection_mark_for_close at %s:%d"
" (first at %s:%d)", file, line, conn->marked_for_close_file,
conn->marked_for_close);
tor_fragile_assert();
return;
}
if (conn->type == CONN_TYPE_OR) {
/*
* Bad news if this happens without telling the controlling channel; do
* this so we can find things that call this wrongly when the asserts hit.
*/
log_debug(LD_CHANNEL,
"Calling connection_mark_for_close_internal_() on an OR conn "
"at %s:%d",
file, line);
}
conn->marked_for_close = line;
conn->marked_for_close_file = file;
add_connection_to_closeable_list(conn);
/* in case we're going to be held-open-til-flushed, reset
* the number of seconds since last successful write, so
* we get our whole 15 seconds */
conn->timestamp_lastwritten = time(NULL);
}
/** Find each connection that has hold_open_until_flushed set to
* 1 but hasn't written in the past 15 seconds, and set
* hold_open_until_flushed to 0. This means it will get cleaned
* up in the next loop through close_if_marked() in main.c.
*/
void
connection_expire_held_open(void)
{
time_t now;
smartlist_t *conns = get_connection_array();
now = time(NULL);
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) {
/* If we've been holding the connection open, but we haven't written
* for 15 seconds...
*/
if (conn->hold_open_until_flushed) {
tor_assert(conn->marked_for_close);
if (now - conn->timestamp_lastwritten >= 15) {
int severity;
if (conn->type == CONN_TYPE_EXIT ||
(conn->type == CONN_TYPE_DIR &&
conn->purpose == DIR_PURPOSE_SERVER))
severity = LOG_INFO;
else
severity = LOG_NOTICE;
log_fn(severity, LD_NET,
"Giving up on marked_for_close conn that's been flushing "
"for 15s (fd %d, type %s, state %s).",
(int)conn->s, conn_type_to_string(conn->type),
conn_state_to_string(conn->type, conn->state));
conn->hold_open_until_flushed = 0;
}
}
} SMARTLIST_FOREACH_END(conn);
}
#if defined(HAVE_SYS_UN_H) || defined(RUNNING_DOXYGEN)
/** Create an AF_UNIX listenaddr struct.
* <b>listenaddress</b> provides the path to the Unix socket.
*
* Eventually <b>listenaddress</b> will also optionally contain user, group,
* and file permissions for the new socket. But not yet. XXX
* Also, since we do not create the socket here the information doesn't help
* here.
*
* If not NULL <b>readable_address</b> will contain a copy of the path part of
* <b>listenaddress</b>.
*
* The listenaddr struct has to be freed by the caller.
*/
static struct sockaddr_un *
create_unix_sockaddr(const char *listenaddress, char **readable_address,
socklen_t *len_out)
{
struct sockaddr_un *sockaddr = NULL;
sockaddr = tor_malloc_zero(sizeof(struct sockaddr_un));
sockaddr->sun_family = AF_UNIX;
if (strlcpy(sockaddr->sun_path, listenaddress, sizeof(sockaddr->sun_path))
>= sizeof(sockaddr->sun_path)) {
log_warn(LD_CONFIG, "Unix socket path '%s' is too long to fit.",
escaped(listenaddress));
tor_free(sockaddr);
return NULL;
}
if (readable_address)
*readable_address = tor_strdup(listenaddress);
*len_out = sizeof(struct sockaddr_un);
return sockaddr;
}
#else
static struct sockaddr *
create_unix_sockaddr(const char *listenaddress, char **readable_address,
socklen_t *len_out)
{
(void)listenaddress;
(void)readable_address;
log_fn(LOG_ERR, LD_BUG,
"Unix domain sockets not supported, yet we tried to create one.");
*len_out = 0;
tor_fragile_assert();
return NULL;
}
#endif /* HAVE_SYS_UN_H */
/** Warn that an accept or a connect has failed because we're running out of
* TCP sockets we can use on current system. Rate-limit these warnings so
* that we don't spam the log. */
static void
warn_too_many_conns(void)
{
#define WARN_TOO_MANY_CONNS_INTERVAL (6*60*60)
static ratelim_t last_warned = RATELIM_INIT(WARN_TOO_MANY_CONNS_INTERVAL);
char *m;
if ((m = rate_limit_log(&last_warned, approx_time()))) {
int n_conns = get_n_open_sockets();
log_warn(LD_NET,"Failing because we have %d connections already. Please "
"read doc/TUNING for guidance.%s", n_conns, m);
tor_free(m);
control_event_general_status(LOG_WARN, "TOO_MANY_CONNECTIONS CURRENT=%d",
n_conns);
}
}
#ifdef HAVE_SYS_UN_H
#define UNIX_SOCKET_PURPOSE_CONTROL_SOCKET 0
#define UNIX_SOCKET_PURPOSE_SOCKS_SOCKET 1
/** Check if the purpose isn't one of the ones we know what to do with */
static int
is_valid_unix_socket_purpose(int purpose)
{
int valid = 0;
switch (purpose) {
case UNIX_SOCKET_PURPOSE_CONTROL_SOCKET:
case UNIX_SOCKET_PURPOSE_SOCKS_SOCKET:
valid = 1;
break;
}
return valid;
}
/** Return a string description of a unix socket purpose */
static const char *
unix_socket_purpose_to_string(int purpose)
{
const char *s = "unknown-purpose socket";
switch (purpose) {
case UNIX_SOCKET_PURPOSE_CONTROL_SOCKET:
s = "control socket";
break;
case UNIX_SOCKET_PURPOSE_SOCKS_SOCKET:
s = "SOCKS socket";
break;
}
return s;
}
/** Check whether we should be willing to open an AF_UNIX socket in
* <b>path</b>. Return 0 if we should go ahead and -1 if we shouldn't. */
static int
check_location_for_unix_socket(const or_options_t *options, const char *path,
int purpose, const port_cfg_t *port)
{
int r = -1;
char *p = NULL;
tor_assert(is_valid_unix_socket_purpose(purpose));
p = tor_strdup(path);
cpd_check_t flags = CPD_CHECK_MODE_ONLY;
if (get_parent_directory(p)<0 || p[0] != '/') {
log_warn(LD_GENERAL, "Bad unix socket address '%s'. Tor does not support "
"relative paths for unix sockets.", path);
goto done;
}
if (port->is_world_writable) {
/* World-writable sockets can go anywhere. */
r = 0;
goto done;
}
if (port->is_group_writable) {
flags |= CPD_GROUP_OK;
}
if (port->relax_dirmode_check) {
flags |= CPD_RELAX_DIRMODE_CHECK;
}
if (check_private_dir(p, flags, options->User) < 0) {
char *escpath, *escdir;
escpath = esc_for_log(path);
escdir = esc_for_log(p);
log_warn(LD_GENERAL, "Before Tor can create a %s in %s, the directory "
"%s needs to exist, and to be accessible only by the user%s "
"account that is running Tor. (On some Unix systems, anybody "
"who can list a socket can connect to it, so Tor is being "
"careful.)",
unix_socket_purpose_to_string(purpose), escpath, escdir,
port->is_group_writable ? " and group" : "");
tor_free(escpath);
tor_free(escdir);
goto done;
}
r = 0;
done:
tor_free(p);
return r;
}
#endif
/** Tell the TCP stack that it shouldn't wait for a long time after
* <b>sock</b> has closed before reusing its port. Return 0 on success,
* -1 on failure. */
static int
make_socket_reuseable(tor_socket_t sock)
{
#ifdef _WIN32
(void) sock;
return 0;
#else
int one=1;
/* REUSEADDR on normal places means you can rebind to the port
* right after somebody else has let it go. But REUSEADDR on win32
* means you can bind to the port _even when somebody else
* already has it bound_. So, don't do that on Win32. */
if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void*) &one,
(socklen_t)sizeof(one)) == -1) {
return -1;
}
return 0;
#endif
}
#ifdef _WIN32
/** Tell the Windows TCP stack to prevent other applications from receiving
* traffic from tor's open ports. Return 0 on success, -1 on failure. */
static int
make_win32_socket_exclusive(tor_socket_t sock)
{
#ifdef SO_EXCLUSIVEADDRUSE
int one=1;
/* Any socket that sets REUSEADDR on win32 can bind to a port _even when
* somebody else already has it bound_, and _even if the original socket
* didn't set REUSEADDR_. Use EXCLUSIVEADDRUSE to prevent this port-stealing
* on win32. */
if (setsockopt(sock, SOL_SOCKET, SO_EXCLUSIVEADDRUSE, (void*) &one,
(socklen_t)sizeof(one))) {
return -1;
}
return 0;
#else
(void) sock;
return 0;
#endif
}
#endif
/** Max backlog to pass to listen. We start at */
static int listen_limit = INT_MAX;
/* Listen on <b>fd</b> with appropriate backlog. Return as for listen. */
static int
tor_listen(tor_socket_t fd)
{
int r;
if ((r = listen(fd, listen_limit)) < 0) {
if (listen_limit == SOMAXCONN)
return r;
if ((r = listen(fd, SOMAXCONN)) == 0) {
listen_limit = SOMAXCONN;
log_warn(LD_NET, "Setting listen backlog to INT_MAX connections "
"didn't work, but SOMAXCONN did. Lowering backlog limit.");
}
}
return r;
}
/** Bind a new non-blocking socket listening to the socket described
* by <b>listensockaddr</b>.
*
* <b>address</b> is only used for logging purposes and to add the information
* to the conn.
*/
static connection_t *
connection_listener_new(const struct sockaddr *listensockaddr,
socklen_t socklen,
int type, const char *address,
const port_cfg_t *port_cfg)
{
listener_connection_t *lis_conn;
connection_t *conn = NULL;
tor_socket_t s = TOR_INVALID_SOCKET; /* the socket we're going to make */
or_options_t const *options = get_options();
(void) options; /* Windows doesn't use this. */
#if defined(HAVE_PWD_H) && defined(HAVE_SYS_UN_H)
const struct passwd *pw = NULL;
#endif
uint16_t usePort = 0, gotPort = 0;
int start_reading = 0;
static int global_next_session_group = SESSION_GROUP_FIRST_AUTO;
tor_addr_t addr;
int exhaustion = 0;
if (listensockaddr->sa_family == AF_INET ||
listensockaddr->sa_family == AF_INET6) {
int is_stream = (type != CONN_TYPE_AP_DNS_LISTENER);
if (is_stream)
start_reading = 1;
tor_addr_from_sockaddr(&addr, listensockaddr, &usePort);
log_notice(LD_NET, "Opening %s on %s",
conn_type_to_string(type), fmt_addrport(&addr, usePort));
s = tor_open_socket_nonblocking(tor_addr_family(&addr),
is_stream ? SOCK_STREAM : SOCK_DGRAM,
is_stream ? IPPROTO_TCP: IPPROTO_UDP);
if (!SOCKET_OK(s)) {
int e = tor_socket_errno(s);
if (ERRNO_IS_RESOURCE_LIMIT(e)) {
warn_too_many_conns();
/*
* We'll call the OOS handler at the error exit, so set the
* exhaustion flag for it.
*/
exhaustion = 1;
} else {
log_warn(LD_NET, "Socket creation failed: %s",
tor_socket_strerror(e));
}
goto err;
}
if (make_socket_reuseable(s) < 0) {
log_warn(LD_NET, "Error setting SO_REUSEADDR flag on %s: %s",
conn_type_to_string(type),
tor_socket_strerror(errno));
}
#ifdef _WIN32
if (make_win32_socket_exclusive(s) < 0) {
log_warn(LD_NET, "Error setting SO_EXCLUSIVEADDRUSE flag on %s: %s",
conn_type_to_string(type),
tor_socket_strerror(errno));
}
#endif
#if defined(USE_TRANSPARENT) && defined(IP_TRANSPARENT)
if (options->TransProxyType_parsed == TPT_TPROXY &&
type == CONN_TYPE_AP_TRANS_LISTENER) {
int one = 1;
if (setsockopt(s, SOL_IP, IP_TRANSPARENT, (void*)&one,
(socklen_t)sizeof(one)) < 0) {
const char *extra = "";
int e = tor_socket_errno(s);
if (e == EPERM)
extra = "TransTPROXY requires root privileges or similar"
" capabilities.";
log_warn(LD_NET, "Error setting IP_TRANSPARENT flag: %s.%s",
tor_socket_strerror(e), extra);
}
}
#endif
#ifdef IPV6_V6ONLY
if (listensockaddr->sa_family == AF_INET6) {
int one = 1;
/* We need to set IPV6_V6ONLY so that this socket can't get used for
* IPv4 connections. */
if (setsockopt(s,IPPROTO_IPV6, IPV6_V6ONLY,
(void*)&one, (socklen_t)sizeof(one)) < 0) {
int e = tor_socket_errno(s);
log_warn(LD_NET, "Error setting IPV6_V6ONLY flag: %s",
tor_socket_strerror(e));
/* Keep going; probably not harmful. */
}
}
#endif
if (bind(s,listensockaddr,socklen) < 0) {
const char *helpfulhint = "";
int e = tor_socket_errno(s);
if (ERRNO_IS_EADDRINUSE(e))
helpfulhint = ". Is Tor already running?";
log_warn(LD_NET, "Could not bind to %s:%u: %s%s", address, usePort,
tor_socket_strerror(e), helpfulhint);
goto err;
}
if (is_stream) {
if (tor_listen(s) < 0) {
log_warn(LD_NET, "Could not listen on %s:%u: %s", address, usePort,
tor_socket_strerror(tor_socket_errno(s)));
goto err;
}
}
if (usePort != 0) {
gotPort = usePort;
} else {
tor_addr_t addr2;
struct sockaddr_storage ss;
socklen_t ss_len=sizeof(ss);
if (getsockname(s, (struct sockaddr*)&ss, &ss_len)<0) {
log_warn(LD_NET, "getsockname() couldn't learn address for %s: %s",
conn_type_to_string(type),
tor_socket_strerror(tor_socket_errno(s)));
gotPort = 0;
}
tor_addr_from_sockaddr(&addr2, (struct sockaddr*)&ss, &gotPort);
}
#ifdef HAVE_SYS_UN_H
/*
* AF_UNIX generic setup stuff
*/
} else if (listensockaddr->sa_family == AF_UNIX) {
/* We want to start reading for both AF_UNIX cases */
start_reading = 1;
tor_assert(conn_listener_type_supports_af_unix(type));
if (check_location_for_unix_socket(options, address,
(type == CONN_TYPE_CONTROL_LISTENER) ?
UNIX_SOCKET_PURPOSE_CONTROL_SOCKET :
UNIX_SOCKET_PURPOSE_SOCKS_SOCKET, port_cfg) < 0) {
goto err;
}
log_notice(LD_NET, "Opening %s on %s",
conn_type_to_string(type), address);
tor_addr_make_unspec(&addr);
if (unlink(address) < 0 && errno != ENOENT) {
log_warn(LD_NET, "Could not unlink %s: %s", address,
strerror(errno));
goto err;
}
s = tor_open_socket_nonblocking(AF_UNIX, SOCK_STREAM, 0);
if (! SOCKET_OK(s)) {
int e = tor_socket_errno(s);
if (ERRNO_IS_RESOURCE_LIMIT(e)) {
warn_too_many_conns();
/*
* We'll call the OOS handler at the error exit, so set the
* exhaustion flag for it.
*/
exhaustion = 1;
} else {
log_warn(LD_NET,"Socket creation failed: %s.", strerror(e));
}
goto err;
}
if (bind(s, listensockaddr,
(socklen_t)sizeof(struct sockaddr_un)) == -1) {
log_warn(LD_NET,"Bind to %s failed: %s.", address,
tor_socket_strerror(tor_socket_errno(s)));
goto err;
}
#ifdef HAVE_PWD_H
if (options->User) {
pw = tor_getpwnam(options->User);
struct stat st;
if (pw == NULL) {
log_warn(LD_NET,"Unable to chown() %s socket: user %s not found.",
address, options->User);
goto err;
} else if (fstat(s, &st) == 0 &&
st.st_uid == pw->pw_uid && st.st_gid == pw->pw_gid) {
/* No change needed */
} else if (chown(sandbox_intern_string(address),
pw->pw_uid, pw->pw_gid) < 0) {
log_warn(LD_NET,"Unable to chown() %s socket: %s.",
address, strerror(errno));
goto err;
}
}
#endif
{
unsigned mode;
const char *status;
struct stat st;
if (port_cfg->is_world_writable) {
mode = 0666;
status = "world-writable";
} else if (port_cfg->is_group_writable) {
mode = 0660;
status = "group-writable";
} else {
mode = 0600;
status = "private";
}
/* We need to use chmod; fchmod doesn't work on sockets on all
* platforms. */
if (fstat(s, &st) == 0 && (st.st_mode & 0777) == mode) {
/* no change needed */
} else if (chmod(sandbox_intern_string(address), mode) < 0) {
log_warn(LD_FS,"Unable to make %s %s.", address, status);
goto err;
}
}
if (listen(s, SOMAXCONN) < 0) {
log_warn(LD_NET, "Could not listen on %s: %s", address,
tor_socket_strerror(tor_socket_errno(s)));
goto err;
}
#endif /* HAVE_SYS_UN_H */
} else {
log_err(LD_BUG, "Got unexpected address family %d.",
listensockaddr->sa_family);
tor_assert(0);
}
lis_conn = listener_connection_new(type, listensockaddr->sa_family);
conn = TO_CONN(lis_conn);
conn->socket_family = listensockaddr->sa_family;
conn->s = s;
s = TOR_INVALID_SOCKET; /* Prevent double-close */
conn->address = tor_strdup(address);
conn->port = gotPort;
tor_addr_copy(&conn->addr, &addr);
memcpy(&lis_conn->entry_cfg, &port_cfg->entry_cfg, sizeof(entry_port_cfg_t));
if (port_cfg->entry_cfg.isolation_flags) {
lis_conn->entry_cfg.isolation_flags = port_cfg->entry_cfg.isolation_flags;
if (port_cfg->entry_cfg.session_group >= 0) {
lis_conn->entry_cfg.session_group = port_cfg->entry_cfg.session_group;
} else {
/* This can wrap after around INT_MAX listeners are opened. But I don't
* believe that matters, since you would need to open a ridiculous
* number of listeners while keeping the early ones open before you ever
* hit this. An OR with a dozen ports open, for example, would have to
* close and re-open its listeners every second for 4 years nonstop.
*/
lis_conn->entry_cfg.session_group = global_next_session_group--;
}
}
if (type != CONN_TYPE_AP_LISTENER) {
lis_conn->entry_cfg.ipv4_traffic = 1;
lis_conn->entry_cfg.ipv6_traffic = 1;
lis_conn->entry_cfg.prefer_ipv6 = 0;
}
if (connection_add(conn) < 0) { /* no space, forget it */
log_warn(LD_NET,"connection_add for listener failed. Giving up.");
goto err;
}
log_fn(usePort==gotPort ? LOG_DEBUG : LOG_NOTICE, LD_NET,
"%s listening on port %u.",
conn_type_to_string(type), gotPort);
conn->state = LISTENER_STATE_READY;
if (start_reading) {
connection_start_reading(conn);
} else {
tor_assert(type == CONN_TYPE_AP_DNS_LISTENER);
dnsserv_configure_listener(conn);
}
/*
* Normal exit; call the OOS handler since connection count just changed;
* the exhaustion flag will always be zero here though.
*/
connection_check_oos(get_n_open_sockets(), 0);
return conn;
err:
if (SOCKET_OK(s))
tor_close_socket(s);
if (conn)
connection_free(conn);
/* Call the OOS handler, indicate if we saw an exhaustion-related error */
connection_check_oos(get_n_open_sockets(), exhaustion);
return NULL;
}
/** Do basic sanity checking on a newly received socket. Return 0
* if it looks ok, else return -1.
*
* Notably, some TCP stacks can erroneously have accept() return successfully
* with socklen 0, when the client sends an RST before the accept call (as
* nmap does). We want to detect that, and not go on with the connection.
*/
static int
check_sockaddr(const struct sockaddr *sa, int len, int level)
{
int ok = 1;
if (sa->sa_family == AF_INET) {
struct sockaddr_in *sin=(struct sockaddr_in*)sa;
if (len != sizeof(struct sockaddr_in)) {
log_fn(level, LD_NET, "Length of address not as expected: %d vs %d",
len,(int)sizeof(struct sockaddr_in));
ok = 0;
}
if (sin->sin_addr.s_addr == 0 || sin->sin_port == 0) {
log_fn(level, LD_NET,
"Address for new connection has address/port equal to zero.");
ok = 0;
}
} else if (sa->sa_family == AF_INET6) {
struct sockaddr_in6 *sin6=(struct sockaddr_in6*)sa;
if (len != sizeof(struct sockaddr_in6)) {
log_fn(level, LD_NET, "Length of address not as expected: %d vs %d",
len,(int)sizeof(struct sockaddr_in6));
ok = 0;
}
if (tor_mem_is_zero((void*)sin6->sin6_addr.s6_addr, 16) ||
sin6->sin6_port == 0) {
log_fn(level, LD_NET,
"Address for new connection has address/port equal to zero.");
ok = 0;
}
} else if (sa->sa_family == AF_UNIX) {
ok = 1;
} else {
ok = 0;
}
return ok ? 0 : -1;
}
/** Check whether the socket family from an accepted socket <b>got</b> is the
* same as the one that <b>listener</b> is waiting for. If it isn't, log
* a useful message and return -1. Else return 0.
*
* This is annoying, but can apparently happen on some Darwins. */
static int
check_sockaddr_family_match(sa_family_t got, connection_t *listener)
{
if (got != listener->socket_family) {
log_info(LD_BUG, "A listener connection returned a socket with a "
"mismatched family. %s for addr_family %d gave us a socket "
"with address family %d. Dropping.",
conn_type_to_string(listener->type),
(int)listener->socket_family,
(int)got);
return -1;
}
return 0;
}
/** The listener connection <b>conn</b> told poll() it wanted to read.
* Call accept() on conn-\>s, and add the new connection if necessary.
*/
static int
connection_handle_listener_read(connection_t *conn, int new_type)
{
tor_socket_t news; /* the new socket */
connection_t *newconn = 0;
/* information about the remote peer when connecting to other routers */
struct sockaddr_storage addrbuf;
struct sockaddr *remote = (struct sockaddr*)&addrbuf;
/* length of the remote address. Must be whatever accept() needs. */
socklen_t remotelen = (socklen_t)sizeof(addrbuf);
const or_options_t *options = get_options();
tor_assert((size_t)remotelen >= sizeof(struct sockaddr_in));
memset(&addrbuf, 0, sizeof(addrbuf));
news = tor_accept_socket_nonblocking(conn->s,remote,&remotelen);
if (!SOCKET_OK(news)) { /* accept() error */
int e = tor_socket_errno(conn->s);
if (ERRNO_IS_ACCEPT_EAGAIN(e)) {
/*
* they hung up before we could accept(). that's fine.
*
* give the OOS handler a chance to run though
*/
connection_check_oos(get_n_open_sockets(), 0);
return 0;
} else if (ERRNO_IS_RESOURCE_LIMIT(e)) {
warn_too_many_conns();
/* Exhaustion; tell the OOS handler */
connection_check_oos(get_n_open_sockets(), 1);
return 0;
}
/* else there was a real error. */
log_warn(LD_NET,"accept() failed: %s. Closing listener.",
tor_socket_strerror(e));
connection_mark_for_close(conn);
/* Tell the OOS handler about this too */
connection_check_oos(get_n_open_sockets(), 0);
return -1;
}
log_debug(LD_NET,
"Connection accepted on socket %d (child of fd %d).",
(int)news,(int)conn->s);
/* We accepted a new conn; run OOS handler */
connection_check_oos(get_n_open_sockets(), 0);
if (make_socket_reuseable(news) < 0) {
if (tor_socket_errno(news) == EINVAL) {
/* This can happen on OSX if we get a badly timed shutdown. */
log_debug(LD_NET, "make_socket_reuseable returned EINVAL");
} else {
log_warn(LD_NET, "Error setting SO_REUSEADDR flag on %s: %s",
conn_type_to_string(new_type),
tor_socket_strerror(errno));
}
tor_close_socket(news);
return 0;
}
if (options->ConstrainedSockets)
set_constrained_socket_buffers(news, (int)options->ConstrainedSockSize);
if (check_sockaddr_family_match(remote->sa_family, conn) < 0) {
tor_close_socket(news);
return 0;
}
if (conn->socket_family == AF_INET || conn->socket_family == AF_INET6 ||
(conn->socket_family == AF_UNIX && new_type == CONN_TYPE_AP)) {
tor_addr_t addr;
uint16_t port;
if (check_sockaddr(remote, remotelen, LOG_INFO)<0) {
log_info(LD_NET,
"accept() returned a strange address; closing connection.");
tor_close_socket(news);
return 0;
}
tor_addr_from_sockaddr(&addr, remote, &port);
/* process entrance policies here, before we even create the connection */
if (new_type == CONN_TYPE_AP) {
/* check sockspolicy to see if we should accept it */
if (socks_policy_permits_address(&addr) == 0) {
log_notice(LD_APP,
"Denying socks connection from untrusted address %s.",
fmt_and_decorate_addr(&addr));
tor_close_socket(news);
return 0;
}
}
if (new_type == CONN_TYPE_DIR) {
/* check dirpolicy to see if we should accept it */
if (dir_policy_permits_address(&addr) == 0) {
log_notice(LD_DIRSERV,"Denying dir connection from address %s.",
fmt_and_decorate_addr(&addr));
tor_close_socket(news);
return 0;
}
}
newconn = connection_new(new_type, conn->socket_family);
newconn->s = news;
/* remember the remote address */
tor_addr_copy(&newconn->addr, &addr);
if (new_type == CONN_TYPE_AP && conn->socket_family == AF_UNIX) {
newconn->port = 0;
newconn->address = tor_strdup(conn->address);
} else {
newconn->port = port;
newconn->address = tor_addr_to_str_dup(&addr);
}
if (new_type == CONN_TYPE_AP && conn->socket_family != AF_UNIX) {
log_info(LD_NET, "New SOCKS connection opened from %s.",
fmt_and_decorate_addr(&addr));
}
if (new_type == CONN_TYPE_AP && conn->socket_family == AF_UNIX) {
log_info(LD_NET, "New SOCKS AF_UNIX connection opened");
}
if (new_type == CONN_TYPE_CONTROL) {
log_notice(LD_CONTROL, "New control connection opened from %s.",
fmt_and_decorate_addr(&addr));
}
} else if (conn->socket_family == AF_UNIX && conn->type != CONN_TYPE_AP) {
tor_assert(conn->type == CONN_TYPE_CONTROL_LISTENER);
tor_assert(new_type == CONN_TYPE_CONTROL);
log_notice(LD_CONTROL, "New control connection opened.");
newconn = connection_new(new_type, conn->socket_family);
newconn->s = news;
/* remember the remote address -- do we have anything sane to put here? */
tor_addr_make_unspec(&newconn->addr);
newconn->port = 1;
newconn->address = tor_strdup(conn->address);
} else {
tor_assert(0);
};
if (connection_add(newconn) < 0) { /* no space, forget it */
connection_free(newconn);
return 0; /* no need to tear down the parent */
}
if (connection_init_accepted_conn(newconn, TO_LISTENER_CONN(conn)) < 0) {
if (! newconn->marked_for_close)
connection_mark_for_close(newconn);
return 0;
}
return 0;
}
/** Initialize states for newly accepted connection <b>conn</b>.
* If conn is an OR, start the TLS handshake.
* If conn is a transparent AP, get its original destination
* and place it in circuit_wait.
*/
static int
connection_init_accepted_conn(connection_t *conn,
const listener_connection_t *listener)
{
int rv;
connection_start_reading(conn);
switch (conn->type) {
case CONN_TYPE_EXT_OR:
/* 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);
rv = connection_tls_start_handshake(TO_OR_CONN(conn), 1);
if (rv < 0) {
connection_or_close_for_error(TO_OR_CONN(conn), 0);
}
return rv;
break;
case CONN_TYPE_AP:
memcpy(&TO_ENTRY_CONN(conn)->entry_cfg, &listener->entry_cfg,
sizeof(entry_port_cfg_t));
TO_ENTRY_CONN(conn)->nym_epoch = get_signewnym_epoch();
TO_ENTRY_CONN(conn)->socks_request->listener_type = listener->base_.type;
switch (TO_CONN(listener)->type) {
case CONN_TYPE_AP_LISTENER:
conn->state = AP_CONN_STATE_SOCKS_WAIT;
TO_ENTRY_CONN(conn)->socks_request->socks_prefer_no_auth =
listener->entry_cfg.socks_prefer_no_auth;
break;
case CONN_TYPE_AP_TRANS_LISTENER:
TO_ENTRY_CONN(conn)->is_transparent_ap = 1;
/* XXXX028 -- is this correct still, with the addition of
* pending_entry_connections ? */
conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
return connection_ap_process_transparent(TO_ENTRY_CONN(conn));
case CONN_TYPE_AP_NATD_LISTENER:
TO_ENTRY_CONN(conn)->is_transparent_ap = 1;
conn->state = AP_CONN_STATE_NATD_WAIT;
break;
}
break;
case CONN_TYPE_DIR:
conn->purpose = DIR_PURPOSE_SERVER;
conn->state = DIR_CONN_STATE_SERVER_COMMAND_WAIT;
break;
case CONN_TYPE_CONTROL:
conn->state = CONTROL_CONN_STATE_NEEDAUTH;
break;
}
return 0;
}
/** Take conn, make a nonblocking socket; try to connect to
* sa, binding to bindaddr if sa is not localhost. If fail, return -1 and if
* applicable put your best guess about errno into *<b>socket_error</b>.
* If connected return 1, if EAGAIN return 0.
*/
MOCK_IMPL(STATIC int,
connection_connect_sockaddr,(connection_t *conn,
const struct sockaddr *sa,
socklen_t sa_len,
const struct sockaddr *bindaddr,
socklen_t bindaddr_len,
int *socket_error))
{
tor_socket_t s;
int inprogress = 0;
const or_options_t *options = get_options();
tor_assert(conn);
tor_assert(sa);
tor_assert(socket_error);
if (get_options()->DisableNetwork) {
/* We should never even try to connect anyplace if DisableNetwork is set.
* Warn if we do, and refuse to make the connection. */
static ratelim_t disablenet_violated = RATELIM_INIT(30*60);
*socket_error = SOCK_ERRNO(ENETUNREACH);
log_fn_ratelim(&disablenet_violated, LOG_WARN, LD_BUG,
"Tried to open a socket with DisableNetwork set.");
tor_fragile_assert();
return -1;
}
const int protocol_family = sa->sa_family;
const int proto = (sa->sa_family == AF_INET6 ||
sa->sa_family == AF_INET) ? IPPROTO_TCP : 0;
s = tor_open_socket_nonblocking(protocol_family, SOCK_STREAM, proto);
if (! SOCKET_OK(s)) {
/*
* Early OOS handler calls; it matters if it's an exhaustion-related
* error or not.
*/
*socket_error = tor_socket_errno(s);
if (ERRNO_IS_RESOURCE_LIMIT(*socket_error)) {
warn_too_many_conns();
connection_check_oos(get_n_open_sockets(), 1);
} else {
log_warn(LD_NET,"Error creating network socket: %s",
tor_socket_strerror(*socket_error));
connection_check_oos(get_n_open_sockets(), 0);
}
return -1;
}
if (make_socket_reuseable(s) < 0) {
log_warn(LD_NET, "Error setting SO_REUSEADDR flag on new connection: %s",
tor_socket_strerror(errno));
}
/*
* We've got the socket open; give the OOS handler a chance to check
* against configuured maximum socket number, but tell it no exhaustion
* failure.
*/
connection_check_oos(get_n_open_sockets(), 0);
if (bindaddr && bind(s, bindaddr, bindaddr_len) < 0) {
*socket_error = tor_socket_errno(s);
log_warn(LD_NET,"Error binding network socket: %s",
tor_socket_strerror(*socket_error));
tor_close_socket(s);
return -1;
}
tor_assert(options);
if (options->ConstrainedSockets)
set_constrained_socket_buffers(s, (int)options->ConstrainedSockSize);
if (connect(s, sa, sa_len) < 0) {
int e = tor_socket_errno(s);
if (!ERRNO_IS_CONN_EINPROGRESS(e)) {
/* yuck. kill it. */
*socket_error = e;
log_info(LD_NET,
"connect() to socket failed: %s",
tor_socket_strerror(e));
tor_close_socket(s);
return -1;
} else {
inprogress = 1;
}
}
/* it succeeded. we're connected. */
log_fn(inprogress ? LOG_DEBUG : LOG_INFO, LD_NET,
"Connection to socket %s (sock "TOR_SOCKET_T_FORMAT").",
inprogress ? "in progress" : "established", s);
conn->s = s;
if (connection_add_connecting(conn) < 0) {
/* no space, forget it */
*socket_error = SOCK_ERRNO(ENOBUFS);
return -1;
}
return inprogress ? 0 : 1;
}
/* Log a message if connection attempt is made when IPv4 or IPv6 is disabled.
* Log a less severe message if we couldn't conform to ClientPreferIPv6ORPort
* or ClientPreferIPv6ORPort. */
static void
connection_connect_log_client_use_ip_version(const connection_t *conn)
{
const or_options_t *options = get_options();
/* Only clients care about ClientUseIPv4/6, bail out early on servers, and
* on connections we don't care about */
if (server_mode(options) || !conn || conn->type == CONN_TYPE_EXIT) {
return;
}
/* We're only prepared to log OR and DIR connections here */
if (conn->type != CONN_TYPE_OR && conn->type != CONN_TYPE_DIR) {
return;
}
const int must_ipv4 = !fascist_firewall_use_ipv6(options);
const int must_ipv6 = (options->ClientUseIPv4 == 0);
const int pref_ipv6 = (conn->type == CONN_TYPE_OR
? fascist_firewall_prefer_ipv6_orport(options)
: fascist_firewall_prefer_ipv6_dirport(options));
tor_addr_t real_addr;
tor_addr_make_null(&real_addr, AF_UNSPEC);
/* OR conns keep the original address in real_addr, as addr gets overwritten
* with the descriptor address */
if (conn->type == CONN_TYPE_OR) {
const or_connection_t *or_conn = TO_OR_CONN((connection_t *)conn);
tor_addr_copy(&real_addr, &or_conn->real_addr);
} else if (conn->type == CONN_TYPE_DIR) {
tor_addr_copy(&real_addr, &conn->addr);
}
/* Check if we broke a mandatory address family restriction */
if ((must_ipv4 && tor_addr_family(&real_addr) == AF_INET6)
|| (must_ipv6 && tor_addr_family(&real_addr) == AF_INET)) {
static int logged_backtrace = 0;
log_info(LD_BUG, "Outgoing %s connection to %s violated ClientUseIPv%s 0.",
conn->type == CONN_TYPE_OR ? "OR" : "Dir",
fmt_addr(&real_addr),
options->ClientUseIPv4 == 0 ? "4" : "6");
if (!logged_backtrace) {
log_backtrace(LOG_INFO, LD_BUG, "Address came from");
logged_backtrace = 1;
}
}
/* Bridges are allowed to break IPv4/IPv6 ORPort preferences to connect to
* the node's configured address when ClientPreferIPv6ORPort is auto */
if (options->UseBridges && conn->type == CONN_TYPE_OR
&& options->ClientPreferIPv6ORPort == -1) {
return;
}
/* Check if we couldn't satisfy an address family preference */
if ((!pref_ipv6 && tor_addr_family(&real_addr) == AF_INET6)
|| (pref_ipv6 && tor_addr_family(&real_addr) == AF_INET)) {
log_info(LD_NET, "Outgoing connection to %s doesn't satisfy "
"ClientPreferIPv6%sPort %d, with ClientUseIPv4 %d, and "
"fascist_firewall_use_ipv6 %d (ClientUseIPv6 %d and UseBridges "
"%d).",
fmt_addr(&real_addr),
conn->type == CONN_TYPE_OR ? "OR" : "Dir",
conn->type == CONN_TYPE_OR ? options->ClientPreferIPv6ORPort
: options->ClientPreferIPv6DirPort,
options->ClientUseIPv4, fascist_firewall_use_ipv6(options),
options->ClientUseIPv6, options->UseBridges);
}
}
/** Take conn, make a nonblocking socket; try to connect to
* addr:port (port arrives in *host order*). If fail, return -1 and if
* applicable put your best guess about errno into *<b>socket_error</b>.
* Else assign s to conn-\>s: if connected return 1, if EAGAIN return 0.
*
* addr:port can be different to conn->addr:conn->port if connecting through
* a proxy.
*
* address is used to make the logs useful.
*
* On success, add conn to the list of polled connections.
*/
int
connection_connect(connection_t *conn, const char *address,
const tor_addr_t *addr, uint16_t port, int *socket_error)
{
struct sockaddr_storage addrbuf;
struct sockaddr_storage bind_addr_ss;
struct sockaddr *bind_addr = NULL;
struct sockaddr *dest_addr;
int dest_addr_len, bind_addr_len = 0;
const or_options_t *options = get_options();
int protocol_family;
/* Log if we didn't stick to ClientUseIPv4/6 or ClientPreferIPv6OR/DirPort
*/
connection_connect_log_client_use_ip_version(conn);
if (tor_addr_family(addr) == AF_INET6)
protocol_family = PF_INET6;
else
protocol_family = PF_INET;
if (!tor_addr_is_loopback(addr)) {
const tor_addr_t *ext_addr = NULL;
if (protocol_family == AF_INET &&
!tor_addr_is_null(&options->OutboundBindAddressIPv4_))
ext_addr = &options->OutboundBindAddressIPv4_;
else if (protocol_family == AF_INET6 &&
!tor_addr_is_null(&options->OutboundBindAddressIPv6_))
ext_addr = &options->OutboundBindAddressIPv6_;
if (ext_addr) {
memset(&bind_addr_ss, 0, sizeof(bind_addr_ss));
bind_addr_len = tor_addr_to_sockaddr(ext_addr, 0,
(struct sockaddr *) &bind_addr_ss,
sizeof(bind_addr_ss));
if (bind_addr_len == 0) {
log_warn(LD_NET,
"Error converting OutboundBindAddress %s into sockaddr. "
"Ignoring.", fmt_and_decorate_addr(ext_addr));
} else {
bind_addr = (struct sockaddr *)&bind_addr_ss;
}
}
}
memset(&addrbuf,0,sizeof(addrbuf));
dest_addr = (struct sockaddr*) &addrbuf;
dest_addr_len = tor_addr_to_sockaddr(addr, port, dest_addr, sizeof(addrbuf));
tor_assert(dest_addr_len > 0);
log_debug(LD_NET, "Connecting to %s:%u.",
escaped_safe_str_client(address), port);
return connection_connect_sockaddr(conn, dest_addr, dest_addr_len,
bind_addr, bind_addr_len, socket_error);
}
#ifdef HAVE_SYS_UN_H
/** Take conn, make a nonblocking socket; try to connect to
* an AF_UNIX socket at socket_path. If fail, return -1 and if applicable
* put your best guess about errno into *<b>socket_error</b>. Else assign s
* to conn-\>s: if connected return 1, if EAGAIN return 0.
*
* On success, add conn to the list of polled connections.
*/
int
connection_connect_unix(connection_t *conn, const char *socket_path,
int *socket_error)
{
struct sockaddr_un dest_addr;
tor_assert(socket_path);
/* Check that we'll be able to fit it into dest_addr later */
if (strlen(socket_path) + 1 > sizeof(dest_addr.sun_path)) {
log_warn(LD_NET,
"Path %s is too long for an AF_UNIX socket\n",
escaped_safe_str_client(socket_path));
*socket_error = SOCK_ERRNO(ENAMETOOLONG);
return -1;
}
memset(&dest_addr, 0, sizeof(dest_addr));
dest_addr.sun_family = AF_UNIX;
strlcpy(dest_addr.sun_path, socket_path, sizeof(dest_addr.sun_path));
log_debug(LD_NET,
"Connecting to AF_UNIX socket at %s.",
escaped_safe_str_client(socket_path));
return connection_connect_sockaddr(conn,
(struct sockaddr *)&dest_addr, sizeof(dest_addr),
NULL, 0, socket_error);
}
#endif /* defined(HAVE_SYS_UN_H) */
/** Convert state number to string representation for logging purposes.
*/
static const char *
connection_proxy_state_to_string(int state)
{
static const char *unknown = "???";
static const char *states[] = {
"PROXY_NONE",
"PROXY_INFANT",
"PROXY_HTTPS_WANT_CONNECT_OK",
"PROXY_SOCKS4_WANT_CONNECT_OK",
"PROXY_SOCKS5_WANT_AUTH_METHOD_NONE",
"PROXY_SOCKS5_WANT_AUTH_METHOD_RFC1929",
"PROXY_SOCKS5_WANT_AUTH_RFC1929_OK",
"PROXY_SOCKS5_WANT_CONNECT_OK",
"PROXY_CONNECTED",
};
if (state < PROXY_NONE || state > PROXY_CONNECTED)
return unknown;
return states[state];
}
/** Returns the global proxy type used by tor. Use this function for
* logging or high-level purposes, don't use it to fill the
* <b>proxy_type</b> field of or_connection_t; use the actual proxy
* protocol instead.*/
static int
get_proxy_type(void)
{
const or_options_t *options = get_options();
if (options->ClientTransportPlugin)
return PROXY_PLUGGABLE;
else if (options->HTTPSProxy)
return PROXY_CONNECT;
else if (options->Socks4Proxy)
return PROXY_SOCKS4;
else if (options->Socks5Proxy)
return PROXY_SOCKS5;
else
return PROXY_NONE;
}
/* One byte for the version, one for the command, two for the
port, and four for the addr... and, one more for the
username NUL: */
#define SOCKS4_STANDARD_BUFFER_SIZE (1 + 1 + 2 + 4 + 1)
/** Write a proxy request of <b>type</b> (socks4, socks5, https) to conn
* for conn->addr:conn->port, authenticating with the auth details given
* in the configuration (if available). SOCKS 5 and HTTP CONNECT proxies
* support authentication.
*
* Returns -1 if conn->addr is incompatible with the proxy protocol, and
* 0 otherwise.
*
* Use connection_read_proxy_handshake() to complete the handshake.
*/
int
connection_proxy_connect(connection_t *conn, int type)
{
const or_options_t *options;
tor_assert(conn);
options = get_options();
switch (type) {
case PROXY_CONNECT: {
char buf[1024];
char *base64_authenticator=NULL;
const char *authenticator = options->HTTPSProxyAuthenticator;
/* Send HTTP CONNECT and authentication (if available) in
* one request */
if (authenticator) {
base64_authenticator = alloc_http_authenticator(authenticator);
if (!base64_authenticator)
log_warn(LD_OR, "Encoding https authenticator failed");
}
if (base64_authenticator) {
const char *addrport = fmt_addrport(&conn->addr, conn->port);
tor_snprintf(buf, sizeof(buf), "CONNECT %s HTTP/1.1\r\n"
"Host: %s\r\n"
"Proxy-Authorization: Basic %s\r\n\r\n",
addrport,
addrport,
base64_authenticator);
tor_free(base64_authenticator);
} else {
tor_snprintf(buf, sizeof(buf), "CONNECT %s HTTP/1.0\r\n\r\n",
fmt_addrport(&conn->addr, conn->port));
}
connection_write_to_buf(buf, strlen(buf), conn);
conn->proxy_state = PROXY_HTTPS_WANT_CONNECT_OK;
break;
}
case PROXY_SOCKS4: {
unsigned char *buf;
uint16_t portn;
uint32_t ip4addr;
size_t buf_size = 0;
char *socks_args_string = NULL;
/* Send a SOCKS4 connect request */
if (tor_addr_family(&conn->addr) != AF_INET) {
log_warn(LD_NET, "SOCKS4 client is incompatible with IPv6");
return -1;
}
{ /* If we are here because we are trying to connect to a
pluggable transport proxy, check if we have any SOCKS
arguments to transmit. If we do, compress all arguments to
a single string in 'socks_args_string': */
if (get_proxy_type() == PROXY_PLUGGABLE) {
socks_args_string =
pt_get_socks_args_for_proxy_addrport(&conn->addr, conn->port);
if (socks_args_string)
log_debug(LD_NET, "Sending out '%s' as our SOCKS argument string.",
socks_args_string);
}
}
{ /* Figure out the buffer size we need for the SOCKS message: */
buf_size = SOCKS4_STANDARD_BUFFER_SIZE;
/* If we have a SOCKS argument string, consider its size when
calculating the buffer size: */
if (socks_args_string)
buf_size += strlen(socks_args_string);
}
buf = tor_malloc_zero(buf_size);
ip4addr = tor_addr_to_ipv4n(&conn->addr);
portn = htons(conn->port);
buf[0] = 4; /* version */
buf[1] = SOCKS_COMMAND_CONNECT; /* command */
memcpy(buf + 2, &portn, 2); /* port */
memcpy(buf + 4, &ip4addr, 4); /* addr */
/* Next packet field is the userid. If we have pluggable
transport SOCKS arguments, we have to embed them
there. Otherwise, we use an empty userid. */
if (socks_args_string) { /* place the SOCKS args string: */
tor_assert(strlen(socks_args_string) > 0);
tor_assert(buf_size >=
SOCKS4_STANDARD_BUFFER_SIZE + strlen(socks_args_string));
strlcpy((char *)buf + 8, socks_args_string, buf_size - 8);
tor_free(socks_args_string);
} else {
buf[8] = 0; /* no userid */
}
connection_write_to_buf((char *)buf, buf_size, conn);
tor_free(buf);
conn->proxy_state = PROXY_SOCKS4_WANT_CONNECT_OK;
break;
}
case PROXY_SOCKS5: {
unsigned char buf[4]; /* fields: vers, num methods, method list */
/* Send a SOCKS5 greeting (connect request must wait) */
buf[0] = 5; /* version */
/* We have to use SOCKS5 authentication, if we have a
Socks5ProxyUsername or if we want to pass arguments to our
pluggable transport proxy: */
if ((options->Socks5ProxyUsername) ||
(get_proxy_type() == PROXY_PLUGGABLE &&
(get_socks_args_by_bridge_addrport(&conn->addr, conn->port)))) {
/* number of auth methods */
buf[1] = 2;
buf[2] = 0x00; /* no authentication */
buf[3] = 0x02; /* rfc1929 Username/Passwd auth */
conn->proxy_state = PROXY_SOCKS5_WANT_AUTH_METHOD_RFC1929;
} else {
buf[1] = 1;
buf[2] = 0x00; /* no authentication */
conn->proxy_state = PROXY_SOCKS5_WANT_AUTH_METHOD_NONE;
}
connection_write_to_buf((char *)buf, 2 + buf[1], conn);
break;
}
default:
log_err(LD_BUG, "Invalid proxy protocol, %d", type);
tor_fragile_assert();
return -1;
}
log_debug(LD_NET, "set state %s",
connection_proxy_state_to_string(conn->proxy_state));
return 0;
}
/** Read conn's inbuf. If the http response from the proxy is all
* here, make sure it's good news, then return 1. If it's bad news,
* return -1. Else return 0 and hope for better luck next time.
*/
static int
connection_read_https_proxy_response(connection_t *conn)
{
char *headers;
char *reason=NULL;
int status_code;
time_t date_header;
switch (fetch_from_buf_http(conn->inbuf,
&headers, MAX_HEADERS_SIZE,
NULL, NULL, 10000, 0)) {
case -1: /* overflow */
log_warn(LD_PROTOCOL,
"Your https proxy sent back an oversized response. Closing.");
return -1;
case 0:
log_info(LD_NET,"https proxy response not all here yet. Waiting.");
return 0;
/* case 1, fall through */
}
if (parse_http_response(headers, &status_code, &date_header,
NULL, &reason) < 0) {
log_warn(LD_NET,
"Unparseable headers from proxy (connecting to '%s'). Closing.",
conn->address);
tor_free(headers);
return -1;
}
tor_free(headers);
if (!reason) reason = tor_strdup("[no reason given]");
if (status_code == 200) {
log_info(LD_NET,
"HTTPS connect to '%s' successful! (200 %s) Starting TLS.",
conn->address, escaped(reason));
tor_free(reason);
return 1;
}
/* else, bad news on the status code */
switch (status_code) {
case 403:
log_warn(LD_NET,
"The https proxy refused to allow connection to %s "
"(status code %d, %s). Closing.",
conn->address, status_code, escaped(reason));
break;
default:
log_warn(LD_NET,
"The https proxy sent back an unexpected status code %d (%s). "
"Closing.",
status_code, escaped(reason));
break;
}
tor_free(reason);
return -1;
}
/** Send SOCKS5 CONNECT command to <b>conn</b>, copying <b>conn->addr</b>
* and <b>conn->port</b> into the request.
*/
static void
connection_send_socks5_connect(connection_t *conn)
{
unsigned char buf[1024];
size_t reqsize = 6;
uint16_t port = htons(conn->port);
buf[0] = 5; /* version */
buf[1] = SOCKS_COMMAND_CONNECT; /* command */
buf[2] = 0; /* reserved */
if (tor_addr_family(&conn->addr) == AF_INET) {
uint32_t addr = tor_addr_to_ipv4n(&conn->addr);
buf[3] = 1;
reqsize += 4;
memcpy(buf + 4, &addr, 4);
memcpy(buf + 8, &port, 2);
} else { /* AF_INET6 */
buf[3] = 4;
reqsize += 16;
memcpy(buf + 4, tor_addr_to_in6_addr8(&conn->addr), 16);
memcpy(buf + 20, &port, 2);
}
connection_write_to_buf((char *)buf, reqsize, conn);
conn->proxy_state = PROXY_SOCKS5_WANT_CONNECT_OK;
}
/** Wrapper around fetch_from_buf_socks_client: see that functions
* for documentation of its behavior. */
static int
connection_fetch_from_buf_socks_client(connection_t *conn,
int state, char **reason)
{
return fetch_from_buf_socks_client(conn->inbuf, state, reason);
}
/** Call this from connection_*_process_inbuf() to advance the proxy
* handshake.
*
* No matter what proxy protocol is used, if this function returns 1, the
* handshake is complete, and the data remaining on inbuf may contain the
* start of the communication with the requested server.
*
* Returns 0 if the current buffer contains an incomplete response, and -1
* on error.
*/
int
connection_read_proxy_handshake(connection_t *conn)
{
int ret = 0;
char *reason = NULL;
log_debug(LD_NET, "enter state %s",
connection_proxy_state_to_string(conn->proxy_state));
switch (conn->proxy_state) {
case PROXY_HTTPS_WANT_CONNECT_OK:
ret = connection_read_https_proxy_response(conn);
if (ret == 1)
conn->proxy_state = PROXY_CONNECTED;
break;
case PROXY_SOCKS4_WANT_CONNECT_OK:
ret = connection_fetch_from_buf_socks_client(conn,
conn->proxy_state,
&reason);
if (ret == 1)
conn->proxy_state = PROXY_CONNECTED;
break;
case PROXY_SOCKS5_WANT_AUTH_METHOD_NONE:
ret = connection_fetch_from_buf_socks_client(conn,
conn->proxy_state,
&reason);
/* no auth needed, do connect */
if (ret == 1) {
connection_send_socks5_connect(conn);
ret = 0;
}
break;
case PROXY_SOCKS5_WANT_AUTH_METHOD_RFC1929:
ret = connection_fetch_from_buf_socks_client(conn,
conn->proxy_state,
&reason);
/* send auth if needed, otherwise do connect */
if (ret == 1) {
connection_send_socks5_connect(conn);
ret = 0;
} else if (ret == 2) {
unsigned char buf[1024];
size_t reqsize, usize, psize;
const char *user, *pass;
char *socks_args_string = NULL;
if (get_proxy_type() == PROXY_PLUGGABLE) {
socks_args_string =
pt_get_socks_args_for_proxy_addrport(&conn->addr, conn->port);
if (!socks_args_string) {
log_warn(LD_NET, "Could not create SOCKS args string.");
ret = -1;
break;
}
log_debug(LD_NET, "SOCKS5 arguments: %s", socks_args_string);
tor_assert(strlen(socks_args_string) > 0);
tor_assert(strlen(socks_args_string) <= MAX_SOCKS5_AUTH_SIZE_TOTAL);
if (strlen(socks_args_string) > MAX_SOCKS5_AUTH_FIELD_SIZE) {
user = socks_args_string;
usize = MAX_SOCKS5_AUTH_FIELD_SIZE;
pass = socks_args_string + MAX_SOCKS5_AUTH_FIELD_SIZE;
psize = strlen(socks_args_string) - MAX_SOCKS5_AUTH_FIELD_SIZE;
} else {
user = socks_args_string;
usize = strlen(socks_args_string);
pass = "\0";
psize = 1;
}
} else if (get_options()->Socks5ProxyUsername) {
user = get_options()->Socks5ProxyUsername;
pass = get_options()->Socks5ProxyPassword;
tor_assert(user && pass);
usize = strlen(user);
psize = strlen(pass);
} else {
log_err(LD_BUG, "We entered %s for no reason!", __func__);
tor_fragile_assert();
ret = -1;
break;
}
/* Username and password lengths should have been checked
above and during torrc parsing. */
tor_assert(usize <= MAX_SOCKS5_AUTH_FIELD_SIZE &&
psize <= MAX_SOCKS5_AUTH_FIELD_SIZE);
reqsize = 3 + usize + psize;
buf[0] = 1; /* negotiation version */
buf[1] = usize;
memcpy(buf + 2, user, usize);
buf[2 + usize] = psize;
memcpy(buf + 3 + usize, pass, psize);
if (socks_args_string)
tor_free(socks_args_string);
connection_write_to_buf((char *)buf, reqsize, conn);
conn->proxy_state = PROXY_SOCKS5_WANT_AUTH_RFC1929_OK;
ret = 0;
}
break;
case PROXY_SOCKS5_WANT_AUTH_RFC1929_OK:
ret = connection_fetch_from_buf_socks_client(conn,
conn->proxy_state,
&reason);
/* send the connect request */
if (ret == 1) {
connection_send_socks5_connect(conn);
ret = 0;
}
break;
case PROXY_SOCKS5_WANT_CONNECT_OK:
ret = connection_fetch_from_buf_socks_client(conn,
conn->proxy_state,
&reason);
if (ret == 1)
conn->proxy_state = PROXY_CONNECTED;
break;
default:
log_err(LD_BUG, "Invalid proxy_state for reading, %d",
conn->proxy_state);
tor_fragile_assert();
ret = -1;
break;
}
log_debug(LD_NET, "leaving state %s",
connection_proxy_state_to_string(conn->proxy_state));
if (ret < 0) {
if (reason) {
log_warn(LD_NET, "Proxy Client: unable to connect to %s:%d (%s)",
conn->address, conn->port, escaped(reason));
tor_free(reason);
} else {
log_warn(LD_NET, "Proxy Client: unable to connect to %s:%d",
conn->address, conn->port);
}
} else if (ret == 1) {
log_info(LD_NET, "Proxy Client: connection to %s:%d successful",
conn->address, conn->port);
}
return ret;
}
/** Given a list of listener connections in <b>old_conns</b>, and list of
* port_cfg_t entries in <b>ports</b>, open a new listener for every port in
* <b>ports</b> that does not already have a listener in <b>old_conns</b>.
*
* Remove from <b>old_conns</b> every connection that has a corresponding
* entry in <b>ports</b>. Add to <b>new_conns</b> new every connection we
* launch.
*
* If <b>control_listeners_only</b> is true, then we only open control
* listeners, and we do not remove any noncontrol listeners from old_conns.
*
* Return 0 on success, -1 on failure.
**/
static int
retry_listener_ports(smartlist_t *old_conns,
const smartlist_t *ports,
smartlist_t *new_conns,
int control_listeners_only)
{
smartlist_t *launch = smartlist_new();
int r = 0;
if (control_listeners_only) {
SMARTLIST_FOREACH(ports, port_cfg_t *, p, {
if (p->type == CONN_TYPE_CONTROL_LISTENER)
smartlist_add(launch, p);
});
} else {
smartlist_add_all(launch, ports);
}
/* Iterate through old_conns, comparing it to launch: remove from both lists
* each pair of elements that corresponds to the same port. */
SMARTLIST_FOREACH_BEGIN(old_conns, connection_t *, conn) {
const port_cfg_t *found_port = NULL;
/* Okay, so this is a listener. Is it configured? */
SMARTLIST_FOREACH_BEGIN(launch, const port_cfg_t *, wanted) {
if (conn->type != wanted->type)
continue;
if ((conn->socket_family != AF_UNIX && wanted->is_unix_addr) ||
(conn->socket_family == AF_UNIX && ! wanted->is_unix_addr))
continue;
if (wanted->server_cfg.no_listen)
continue; /* We don't want to open a listener for this one */
if (wanted->is_unix_addr) {
if (conn->socket_family == AF_UNIX &&
!strcmp(wanted->unix_addr, conn->address)) {
found_port = wanted;
break;
}
} else {
int port_matches;
if (wanted->port == CFG_AUTO_PORT) {
port_matches = 1;
} else {
port_matches = (wanted->port == conn->port);
}
if (port_matches && tor_addr_eq(&wanted->addr, &conn->addr)) {
found_port = wanted;
break;
}
}
} SMARTLIST_FOREACH_END(wanted);
if (found_port) {
/* This listener is already running; we don't need to launch it. */
//log_debug(LD_NET, "Already have %s on %s:%d",
// conn_type_to_string(found_port->type), conn->address, conn->port);
smartlist_remove(launch, found_port);
/* And we can remove the connection from old_conns too. */
SMARTLIST_DEL_CURRENT(old_conns, conn);
}
} SMARTLIST_FOREACH_END(conn);
/* Now open all the listeners that are configured but not opened. */
SMARTLIST_FOREACH_BEGIN(launch, const port_cfg_t *, port) {
struct sockaddr *listensockaddr;
socklen_t listensocklen = 0;
char *address=NULL;
connection_t *conn;
int real_port = port->port == CFG_AUTO_PORT ? 0 : port->port;
tor_assert(real_port <= UINT16_MAX);
if (port->server_cfg.no_listen)
continue;
#ifndef _WIN32
/* We don't need to be root to create a UNIX socket, so defer until after
* setuid. */
const or_options_t *options = get_options();
if (port->is_unix_addr && !geteuid() && (options->User) &&
strcmp(options->User, "root"))
continue;
#endif
if (port->is_unix_addr) {
listensockaddr = (struct sockaddr *)
create_unix_sockaddr(port->unix_addr,
&address, &listensocklen);
} else {
listensockaddr = tor_malloc(sizeof(struct sockaddr_storage));
listensocklen = tor_addr_to_sockaddr(&port->addr,
real_port,
listensockaddr,
sizeof(struct sockaddr_storage));
address = tor_addr_to_str_dup(&port->addr);
}
if (listensockaddr) {
conn = connection_listener_new(listensockaddr, listensocklen,
port->type, address, port);
tor_free(listensockaddr);
tor_free(address);
} else {
conn = NULL;
}
if (!conn) {
r = -1;
} else {
if (new_conns)
smartlist_add(new_conns, conn);
}
} SMARTLIST_FOREACH_END(port);
smartlist_free(launch);
return r;
}
/** Launch listeners for each port you should have open. Only launch
* listeners who are not already open, and only close listeners we no longer
* want.
*
* Add all old conns that should be closed to <b>replaced_conns</b>.
* Add all new connections to <b>new_conns</b>.
*
* If <b>close_all_noncontrol</b> is true, then we only open control
* listeners, and we close all other listeners.
*/
int
retry_all_listeners(smartlist_t *replaced_conns,
smartlist_t *new_conns, int close_all_noncontrol)
{
smartlist_t *listeners = smartlist_new();
const or_options_t *options = get_options();
int retval = 0;
const uint16_t old_or_port = router_get_advertised_or_port(options);
const uint16_t old_or_port_ipv6 =
router_get_advertised_or_port_by_af(options,AF_INET6);
const uint16_t old_dir_port = router_get_advertised_dir_port(options, 0);
SMARTLIST_FOREACH_BEGIN(get_connection_array(), connection_t *, conn) {
if (connection_is_listener(conn) && !conn->marked_for_close)
smartlist_add(listeners, conn);
} SMARTLIST_FOREACH_END(conn);
if (retry_listener_ports(listeners,
get_configured_ports(),
new_conns,
close_all_noncontrol) < 0)
retval = -1;
/* Any members that were still in 'listeners' don't correspond to
* any configured port. Kill 'em. */
SMARTLIST_FOREACH_BEGIN(listeners, connection_t *, conn) {
log_notice(LD_NET, "Closing no-longer-configured %s on %s:%d",
conn_type_to_string(conn->type), conn->address, conn->port);
if (replaced_conns) {
smartlist_add(replaced_conns, conn);
} else {
connection_close_immediate(conn);
connection_mark_for_close(conn);
}
} SMARTLIST_FOREACH_END(conn);
smartlist_free(listeners);
if (old_or_port != router_get_advertised_or_port(options) ||
old_or_port_ipv6 != router_get_advertised_or_port_by_af(options,
AF_INET6) ||
old_dir_port != router_get_advertised_dir_port(options, 0)) {
/* Our chosen ORPort or DirPort is not what it used to be: the
* descriptor we had (if any) should be regenerated. (We won't
* automatically notice this because of changes in the option,
* since the value could be "auto".) */
mark_my_descriptor_dirty("Chosen Or/DirPort changed");
}
return retval;
}
/** Mark every listener of type other than CONTROL_LISTENER to be closed. */
void
connection_mark_all_noncontrol_listeners(void)
{
SMARTLIST_FOREACH_BEGIN(get_connection_array(), connection_t *, conn) {
if (conn->marked_for_close)
continue;
if (conn->type == CONN_TYPE_CONTROL_LISTENER)
continue;
if (connection_is_listener(conn))
connection_mark_for_close(conn);
} SMARTLIST_FOREACH_END(conn);
}
/** Mark every external connection not used for controllers for close. */
void
connection_mark_all_noncontrol_connections(void)
{
SMARTLIST_FOREACH_BEGIN(get_connection_array(), connection_t *, conn) {
if (conn->marked_for_close)
continue;
switch (conn->type) {
case CONN_TYPE_CONTROL_LISTENER:
case CONN_TYPE_CONTROL:
break;
case CONN_TYPE_AP:
connection_mark_unattached_ap(TO_ENTRY_CONN(conn),
END_STREAM_REASON_HIBERNATING);
break;
case CONN_TYPE_OR:
{
or_connection_t *orconn = TO_OR_CONN(conn);
if (orconn->chan) {
connection_or_close_normally(orconn, 0);
} else {
/*
* There should have been one, but mark for close and hope
* for the best..
*/
connection_mark_for_close(conn);
}
}
break;
default:
connection_mark_for_close(conn);
break;
}
} SMARTLIST_FOREACH_END(conn);
}
/** Return 1 if we should apply rate limiting to <b>conn</b>, and 0
* otherwise.
* Right now this just checks if it's an internal IP address or an
* internal connection. We also should, but don't, check if the connection
* uses pluggable transports, since we should then limit it even if it
* comes from an internal IP address. */
static int
connection_is_rate_limited(connection_t *conn)
{
const or_options_t *options = get_options();
if (conn->linked)
return 0; /* Internal connection */
else if (! options->CountPrivateBandwidth &&
(tor_addr_family(&conn->addr) == AF_UNSPEC || /* no address */
tor_addr_family(&conn->addr) == AF_UNIX || /* no address */
tor_addr_is_internal(&conn->addr, 0)))
return 0; /* Internal address */
else
return 1;
}
/** Did either global write bucket run dry last second? If so,
* we are likely to run dry again this second, so be stingy with the
* tokens we just put in. */
static int write_buckets_empty_last_second = 0;
/** How many seconds of no active local circuits will make the
* connection revert to the "relayed" bandwidth class? */
#define CLIENT_IDLE_TIME_FOR_PRIORITY 30
/** Return 1 if <b>conn</b> should use tokens from the "relayed"
* bandwidth rates, else 0. Currently, only OR conns with bandwidth
* class 1, and directory conns that are serving data out, count.
*/
static int
connection_counts_as_relayed_traffic(connection_t *conn, time_t now)
{
if (conn->type == CONN_TYPE_OR &&
connection_or_client_used(TO_OR_CONN(conn)) +
CLIENT_IDLE_TIME_FOR_PRIORITY < now)
return 1;
if (conn->type == CONN_TYPE_DIR && DIR_CONN_IS_SERVER(conn))
return 1;
return 0;
}
/** Helper function to decide how many bytes out of <b>global_bucket</b>
* we're willing to use for this transaction. <b>base</b> is the size
* of a cell on the network; <b>priority</b> says whether we should
* write many of them or just a few; and <b>conn_bucket</b> (if
* non-negative) provides an upper limit for our answer. */
static ssize_t
connection_bucket_round_robin(int base, int priority,
ssize_t global_bucket, ssize_t conn_bucket)
{
ssize_t at_most;
ssize_t num_bytes_high = (priority ? 32 : 16) * base;
ssize_t num_bytes_low = (priority ? 4 : 2) * base;
/* Do a rudimentary round-robin so one circuit can't hog a connection.
* Pick at most 32 cells, at least 4 cells if possible, and if we're in
* the middle pick 1/8 of the available bandwidth. */
at_most = global_bucket / 8;
at_most -= (at_most % base); /* round down */
if (at_most > num_bytes_high) /* 16 KB, or 8 KB for low-priority */
at_most = num_bytes_high;
else if (at_most < num_bytes_low) /* 2 KB, or 1 KB for low-priority */
at_most = num_bytes_low;
if (at_most > global_bucket)
at_most = global_bucket;
if (conn_bucket >= 0 && at_most > conn_bucket)
at_most = conn_bucket;
if (at_most < 0)
return 0;
return at_most;
}
/** How many bytes at most can we read onto this connection? */
static ssize_t
connection_bucket_read_limit(connection_t *conn, time_t now)
{
int base = RELAY_PAYLOAD_SIZE;
int priority = conn->type != CONN_TYPE_DIR;
int conn_bucket = -1;
int global_bucket = global_read_bucket;
if (connection_speaks_cells(conn)) {
or_connection_t *or_conn = TO_OR_CONN(conn);
if (conn->state == OR_CONN_STATE_OPEN)
conn_bucket = or_conn->read_bucket;
base = get_cell_network_size(or_conn->wide_circ_ids);
}
if (!connection_is_rate_limited(conn)) {
/* be willing to read on local conns even if our buckets are empty */
return conn_bucket>=0 ? conn_bucket : 1<<14;
}
if (connection_counts_as_relayed_traffic(conn, now) &&
global_relayed_read_bucket <= global_read_bucket)
global_bucket = global_relayed_read_bucket;
return connection_bucket_round_robin(base, priority,
global_bucket, conn_bucket);
}
/** How many bytes at most can we write onto this connection? */
ssize_t
connection_bucket_write_limit(connection_t *conn, time_t now)
{
int base = RELAY_PAYLOAD_SIZE;
int priority = conn->type != CONN_TYPE_DIR;
int conn_bucket = (int)conn->outbuf_flushlen;
int global_bucket = global_write_bucket;
if (!connection_is_rate_limited(conn)) {
/* be willing to write to local conns even if our buckets are empty */
return conn->outbuf_flushlen;
}
if (connection_speaks_cells(conn)) {
/* use the per-conn write limit if it's lower, but if it's less
* than zero just use zero */
or_connection_t *or_conn = TO_OR_CONN(conn);
if (conn->state == OR_CONN_STATE_OPEN)
if (or_conn->write_bucket < conn_bucket)
conn_bucket = or_conn->write_bucket >= 0 ?
or_conn->write_bucket : 0;
base = get_cell_network_size(or_conn->wide_circ_ids);
}
if (connection_counts_as_relayed_traffic(conn, now) &&
global_relayed_write_bucket <= global_write_bucket)
global_bucket = global_relayed_write_bucket;
return connection_bucket_round_robin(base, priority,
global_bucket, conn_bucket);
}
/** Return 1 if the global write buckets are low enough that we
* shouldn't send <b>attempt</b> bytes of low-priority directory stuff
* out to <b>conn</b>. Else return 0.
* Priority was 1 for v1 requests (directories and running-routers),
* and 2 for v2 requests and later (statuses and descriptors).
*
* There are a lot of parameters we could use here:
* - global_relayed_write_bucket. Low is bad.
* - global_write_bucket. Low is bad.
* - bandwidthrate. Low is bad.
* - bandwidthburst. Not a big factor?
* - attempt. High is bad.
* - total bytes queued on outbufs. High is bad. But I'm wary of
* using this, since a few slow-flushing queues will pump up the
* number without meaning what we meant to mean. What we really
* mean is "total directory bytes added to outbufs recently", but
* that's harder to quantify and harder to keep track of.
*/
int
global_write_bucket_low(connection_t *conn, size_t attempt, int priority)
{
int smaller_bucket = global_write_bucket < global_relayed_write_bucket ?
global_write_bucket : global_relayed_write_bucket;
if (authdir_mode(get_options()) && priority>1)
return 0; /* there's always room to answer v2 if we're an auth dir */
if (!connection_is_rate_limited(conn))
return 0; /* local conns don't get limited */
if (smaller_bucket < (int)attempt)
return 1; /* not enough space no matter the priority */
if (write_buckets_empty_last_second)
return 1; /* we're already hitting our limits, no more please */
if (priority == 1) { /* old-style v1 query */
/* Could we handle *two* of these requests within the next two seconds? */
const or_options_t *options = get_options();
int64_t can_write = (int64_t)smaller_bucket
+ 2*(options->RelayBandwidthRate ? options->RelayBandwidthRate :
options->BandwidthRate);
if (can_write < 2*(int64_t)attempt)
return 1;
} else { /* v2 query */
/* no further constraints yet */
}
return 0;
}
/** Helper: adjusts our bandwidth history and informs the controller as
* appropriate, given that we have just read <b>num_read</b> bytes and written
* <b>num_written</b> bytes on <b>conn</b>. */
static void
record_num_bytes_transferred_impl(connection_t *conn,
time_t now, size_t num_read, size_t num_written)
{
/* Count bytes of answering direct and tunneled directory requests */
if (conn->type == CONN_TYPE_DIR && conn->purpose == DIR_PURPOSE_SERVER) {
if (num_read > 0)
rep_hist_note_dir_bytes_read(num_read, now);
if (num_written > 0)
rep_hist_note_dir_bytes_written(num_written, now);
}
if (!connection_is_rate_limited(conn))
return; /* local IPs are free */
if (conn->type == CONN_TYPE_OR)
rep_hist_note_or_conn_bytes(conn->global_identifier, num_read,
num_written, now);
if (num_read > 0) {
rep_hist_note_bytes_read(num_read, now);
}
if (num_written > 0) {
rep_hist_note_bytes_written(num_written, now);
}
if (conn->type == CONN_TYPE_EXIT)
rep_hist_note_exit_bytes(conn->port, num_written, num_read);
}
/** Helper: convert given <b>tvnow</b> time value to milliseconds since
* midnight. */
static uint32_t
msec_since_midnight(const struct timeval *tvnow)
{
return (uint32_t)(((tvnow->tv_sec % 86400L) * 1000L) +
((uint32_t)tvnow->tv_usec / (uint32_t)1000L));
}
/** Helper: return the time in milliseconds since <b>last_empty_time</b>
* when a bucket ran empty that previously had <b>tokens_before</b> tokens
* now has <b>tokens_after</b> tokens after refilling at timestamp
* <b>tvnow</b>, capped at <b>milliseconds_elapsed</b> milliseconds since
* last refilling that bucket. Return 0 if the bucket has not been empty
* since the last refill or has not been refilled. */
uint32_t
bucket_millis_empty(int tokens_before, uint32_t last_empty_time,
int tokens_after, int milliseconds_elapsed,
const struct timeval *tvnow)
{
uint32_t result = 0, refilled;
if (tokens_before <= 0 && tokens_after > tokens_before) {
refilled = msec_since_midnight(tvnow);
result = (uint32_t)((refilled + 86400L * 1000L - last_empty_time) %
(86400L * 1000L));
if (result > (uint32_t)milliseconds_elapsed)
result = (uint32_t)milliseconds_elapsed;
}
return result;
}
/** Check if a bucket which had <b>tokens_before</b> tokens and which got
* <b>tokens_removed</b> tokens removed at timestamp <b>tvnow</b> has run
* out of tokens, and if so, note the milliseconds since midnight in
* <b>timestamp_var</b> for the next TB_EMPTY event. */
void
connection_buckets_note_empty_ts(uint32_t *timestamp_var,
int tokens_before, size_t tokens_removed,
const struct timeval *tvnow)
{
if (tokens_before > 0 && (uint32_t)tokens_before <= tokens_removed)
*timestamp_var = msec_since_midnight(tvnow);
}
/** Last time at which the global or relay buckets were emptied in msec
* since midnight. */
static uint32_t global_relayed_read_emptied = 0,
global_relayed_write_emptied = 0,
global_read_emptied = 0,
global_write_emptied = 0;
/** We just read <b>num_read</b> and wrote <b>num_written</b> bytes
* onto <b>conn</b>. Decrement buckets appropriately. */
static void
connection_buckets_decrement(connection_t *conn, time_t now,
size_t num_read, size_t num_written)
{
if (num_written >= INT_MAX || num_read >= INT_MAX) {
log_err(LD_BUG, "Value out of range. num_read=%lu, num_written=%lu, "
"connection type=%s, state=%s",
(unsigned long)num_read, (unsigned long)num_written,
conn_type_to_string(conn->type),
conn_state_to_string(conn->type, conn->state));
if (num_written >= INT_MAX) num_written = 1;
if (num_read >= INT_MAX) num_read = 1;
tor_fragile_assert();
}
record_num_bytes_transferred_impl(conn, now, num_read, num_written);
if (!connection_is_rate_limited(conn))
return; /* local IPs are free */
/* If one or more of our token buckets ran dry just now, note the
* timestamp for TB_EMPTY events. */
if (get_options()->TestingEnableTbEmptyEvent) {
struct timeval tvnow;
tor_gettimeofday_cached(&tvnow);
if (connection_counts_as_relayed_traffic(conn, now)) {
connection_buckets_note_empty_ts(&global_relayed_read_emptied,
global_relayed_read_bucket, num_read, &tvnow);
connection_buckets_note_empty_ts(&global_relayed_write_emptied,
global_relayed_write_bucket, num_written, &tvnow);
}
connection_buckets_note_empty_ts(&global_read_emptied,
global_read_bucket, num_read, &tvnow);
connection_buckets_note_empty_ts(&global_write_emptied,
global_write_bucket, num_written, &tvnow);
if (connection_speaks_cells(conn) && conn->state == OR_CONN_STATE_OPEN) {
or_connection_t *or_conn = TO_OR_CONN(conn);
connection_buckets_note_empty_ts(&or_conn->read_emptied_time,
or_conn->read_bucket, num_read, &tvnow);
connection_buckets_note_empty_ts(&or_conn->write_emptied_time,
or_conn->write_bucket, num_written, &tvnow);
}
}
if (connection_counts_as_relayed_traffic(conn, now)) {
global_relayed_read_bucket -= (int)num_read;
global_relayed_write_bucket -= (int)num_written;
}
global_read_bucket -= (int)num_read;
global_write_bucket -= (int)num_written;
if (connection_speaks_cells(conn) && conn->state == OR_CONN_STATE_OPEN) {
TO_OR_CONN(conn)->read_bucket -= (int)num_read;
TO_OR_CONN(conn)->write_bucket -= (int)num_written;
}
}
/** If we have exhausted our global buckets, or the buckets for conn,
* stop reading. */
static void
connection_consider_empty_read_buckets(connection_t *conn)
{
const char *reason;
if (!connection_is_rate_limited(conn))
return; /* Always okay. */
if (global_read_bucket <= 0) {
reason = "global read bucket exhausted. Pausing.";
} else if (connection_counts_as_relayed_traffic(conn, approx_time()) &&
global_relayed_read_bucket <= 0) {
reason = "global relayed read bucket exhausted. Pausing.";
} else if (connection_speaks_cells(conn) &&
conn->state == OR_CONN_STATE_OPEN &&
TO_OR_CONN(conn)->read_bucket <= 0) {
reason = "connection read bucket exhausted. Pausing.";
} else
return; /* all good, no need to stop it */
LOG_FN_CONN(conn, (LOG_DEBUG, LD_NET, "%s", reason));
conn->read_blocked_on_bw = 1;
connection_stop_reading(conn);
}
/** If we have exhausted our global buckets, or the buckets for conn,
* stop writing. */
static void
connection_consider_empty_write_buckets(connection_t *conn)
{
const char *reason;
if (!connection_is_rate_limited(conn))
return; /* Always okay. */
if (global_write_bucket <= 0) {
reason = "global write bucket exhausted. Pausing.";
} else if (connection_counts_as_relayed_traffic(conn, approx_time()) &&
global_relayed_write_bucket <= 0) {
reason = "global relayed write bucket exhausted. Pausing.";
} else if (connection_speaks_cells(conn) &&
conn->state == OR_CONN_STATE_OPEN &&
TO_OR_CONN(conn)->write_bucket <= 0) {
reason = "connection write bucket exhausted. Pausing.";
} else
return; /* all good, no need to stop it */
LOG_FN_CONN(conn, (LOG_DEBUG, LD_NET, "%s", reason));
conn->write_blocked_on_bw = 1;
connection_stop_writing(conn);
}
/** Initialize the global read bucket to options-\>BandwidthBurst. */
void
connection_bucket_init(void)
{
const or_options_t *options = get_options();
/* start it at max traffic */
global_read_bucket = (int)options->BandwidthBurst;
global_write_bucket = (int)options->BandwidthBurst;
if (options->RelayBandwidthRate) {
global_relayed_read_bucket = (int)options->RelayBandwidthBurst;
global_relayed_write_bucket = (int)options->RelayBandwidthBurst;
} else {
global_relayed_read_bucket = (int)options->BandwidthBurst;
global_relayed_write_bucket = (int)options->BandwidthBurst;
}
}
/** Refill a single <b>bucket</b> called <b>name</b> with bandwidth rate per
* second <b>rate</b> and bandwidth burst <b>burst</b>, assuming that
* <b>milliseconds_elapsed</b> milliseconds have passed since the last
* call. */
static void
connection_bucket_refill_helper(int *bucket, int rate, int burst,
int milliseconds_elapsed,
const char *name)
{
int starting_bucket = *bucket;
if (starting_bucket < burst && milliseconds_elapsed > 0) {
int64_t incr = (((int64_t)rate) * milliseconds_elapsed) / 1000;
if ((burst - starting_bucket) < incr) {
*bucket = burst; /* We would overflow the bucket; just set it to
* the maximum. */
} else {
*bucket += (int)incr;
if (*bucket > burst || *bucket < starting_bucket) {
/* If we overflow the burst, or underflow our starting bucket,
* cap the bucket value to burst. */
/* XXXX this might be redundant now, but it doesn't show up
* in profiles. Remove it after analysis. */
*bucket = burst;
}
}
log_debug(LD_NET,"%s now %d.", name, *bucket);
}
}
/** Time has passed; increment buckets appropriately. */
void
connection_bucket_refill(int milliseconds_elapsed, time_t now)
{
const or_options_t *options = get_options();
smartlist_t *conns = get_connection_array();
int bandwidthrate, bandwidthburst, relayrate, relayburst;
int prev_global_read = global_read_bucket;
int prev_global_write = global_write_bucket;
int prev_relay_read = global_relayed_read_bucket;
int prev_relay_write = global_relayed_write_bucket;
struct timeval tvnow; /*< Only used if TB_EMPTY events are enabled. */
bandwidthrate = (int)options->BandwidthRate;
bandwidthburst = (int)options->BandwidthBurst;
if (options->RelayBandwidthRate) {
relayrate = (int)options->RelayBandwidthRate;
relayburst = (int)options->RelayBandwidthBurst;
} else {
relayrate = bandwidthrate;
relayburst = bandwidthburst;
}
tor_assert(milliseconds_elapsed >= 0);
write_buckets_empty_last_second =
global_relayed_write_bucket <= 0 || global_write_bucket <= 0;
/* refill the global buckets */
connection_bucket_refill_helper(&global_read_bucket,
bandwidthrate, bandwidthburst,
milliseconds_elapsed,
"global_read_bucket");
connection_bucket_refill_helper(&global_write_bucket,
bandwidthrate, bandwidthburst,
milliseconds_elapsed,
"global_write_bucket");
connection_bucket_refill_helper(&global_relayed_read_bucket,
relayrate, relayburst,
milliseconds_elapsed,
"global_relayed_read_bucket");
connection_bucket_refill_helper(&global_relayed_write_bucket,
relayrate, relayburst,
milliseconds_elapsed,
"global_relayed_write_bucket");
/* If buckets were empty before and have now been refilled, tell any
* interested controllers. */
if (get_options()->TestingEnableTbEmptyEvent) {
uint32_t global_read_empty_time, global_write_empty_time,
relay_read_empty_time, relay_write_empty_time;
tor_gettimeofday_cached(&tvnow);
global_read_empty_time = bucket_millis_empty(prev_global_read,
global_read_emptied, global_read_bucket,
milliseconds_elapsed, &tvnow);
global_write_empty_time = bucket_millis_empty(prev_global_write,
global_write_emptied, global_write_bucket,
milliseconds_elapsed, &tvnow);
control_event_tb_empty("GLOBAL", global_read_empty_time,
global_write_empty_time, milliseconds_elapsed);
relay_read_empty_time = bucket_millis_empty(prev_relay_read,
global_relayed_read_emptied,
global_relayed_read_bucket,
milliseconds_elapsed, &tvnow);
relay_write_empty_time = bucket_millis_empty(prev_relay_write,
global_relayed_write_emptied,
global_relayed_write_bucket,
milliseconds_elapsed, &tvnow);
control_event_tb_empty("RELAY", relay_read_empty_time,
relay_write_empty_time, milliseconds_elapsed);
}
/* refill the per-connection buckets */
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) {
if (connection_speaks_cells(conn)) {
or_connection_t *or_conn = TO_OR_CONN(conn);
int orbandwidthrate = or_conn->bandwidthrate;
int orbandwidthburst = or_conn->bandwidthburst;
int prev_conn_read = or_conn->read_bucket;
int prev_conn_write = or_conn->write_bucket;
if (connection_bucket_should_increase(or_conn->read_bucket, or_conn)) {
connection_bucket_refill_helper(&or_conn->read_bucket,
orbandwidthrate,
orbandwidthburst,
milliseconds_elapsed,
"or_conn->read_bucket");
}
if (connection_bucket_should_increase(or_conn->write_bucket, or_conn)) {
connection_bucket_refill_helper(&or_conn->write_bucket,
orbandwidthrate,
orbandwidthburst,
milliseconds_elapsed,
"or_conn->write_bucket");
}
/* If buckets were empty before and have now been refilled, tell any
* interested controllers. */
if (get_options()->TestingEnableTbEmptyEvent) {
char *bucket;
uint32_t conn_read_empty_time, conn_write_empty_time;
tor_asprintf(&bucket, "ORCONN ID="U64_FORMAT,
U64_PRINTF_ARG(or_conn->base_.global_identifier));
conn_read_empty_time = bucket_millis_empty(prev_conn_read,
or_conn->read_emptied_time,
or_conn->read_bucket,
milliseconds_elapsed, &tvnow);
conn_write_empty_time = bucket_millis_empty(prev_conn_write,
or_conn->write_emptied_time,
or_conn->write_bucket,
milliseconds_elapsed, &tvnow);
control_event_tb_empty(bucket, conn_read_empty_time,
conn_write_empty_time,
milliseconds_elapsed);
tor_free(bucket);
}
}
if (conn->read_blocked_on_bw == 1 /* marked to turn reading back on now */
&& global_read_bucket > 0 /* and we're allowed to read */
&& (!connection_counts_as_relayed_traffic(conn, now) ||
global_relayed_read_bucket > 0) /* even if we're relayed traffic */
&& (!connection_speaks_cells(conn) ||
conn->state != OR_CONN_STATE_OPEN ||
TO_OR_CONN(conn)->read_bucket > 0)) {
/* and either a non-cell conn or a cell conn with non-empty bucket */
LOG_FN_CONN(conn, (LOG_DEBUG,LD_NET,
"waking up conn (fd %d) for read", (int)conn->s));
conn->read_blocked_on_bw = 0;
connection_start_reading(conn);
}
if (conn->write_blocked_on_bw == 1
&& global_write_bucket > 0 /* and we're allowed to write */
&& (!connection_counts_as_relayed_traffic(conn, now) ||
global_relayed_write_bucket > 0) /* even if it's relayed traffic */
&& (!connection_speaks_cells(conn) ||
conn->state != OR_CONN_STATE_OPEN ||
TO_OR_CONN(conn)->write_bucket > 0)) {
LOG_FN_CONN(conn, (LOG_DEBUG,LD_NET,
"waking up conn (fd %d) for write", (int)conn->s));
conn->write_blocked_on_bw = 0;
connection_start_writing(conn);
}
} SMARTLIST_FOREACH_END(conn);
}
/** Is the <b>bucket</b> for connection <b>conn</b> low enough that we
* should add another pile of tokens to it?
*/
static int
connection_bucket_should_increase(int bucket, or_connection_t *conn)
{
tor_assert(conn);
if (conn->base_.state != OR_CONN_STATE_OPEN)
return 0; /* only open connections play the rate limiting game */
if (bucket >= conn->bandwidthburst)
return 0;
return 1;
}
/** Read bytes from conn-\>s and process them.
*
* It calls connection_read_to_buf() to bring in any new bytes,
* and then calls connection_process_inbuf() to process them.
*
* Mark the connection and return -1 if you want to close it, else
* return 0.
*/
static int
connection_handle_read_impl(connection_t *conn)
{
ssize_t max_to_read=-1, try_to_read;
size_t before, n_read = 0;
int socket_error = 0;
if (conn->marked_for_close)
return 0; /* do nothing */
conn->timestamp_lastread = approx_time();
switch (conn->type) {
case CONN_TYPE_OR_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_OR);
case CONN_TYPE_EXT_OR_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_EXT_OR);
case CONN_TYPE_AP_LISTENER:
case CONN_TYPE_AP_TRANS_LISTENER:
case CONN_TYPE_AP_NATD_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_AP);
case CONN_TYPE_DIR_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_DIR);
case CONN_TYPE_CONTROL_LISTENER:
return connection_handle_listener_read(conn, CONN_TYPE_CONTROL);
case CONN_TYPE_AP_DNS_LISTENER:
/* This should never happen; eventdns.c handles the reads here. */
tor_fragile_assert();
return 0;
}
loop_again:
try_to_read = max_to_read;
tor_assert(!conn->marked_for_close);
before = buf_datalen(conn->inbuf);
if (connection_read_to_buf(conn, &max_to_read, &socket_error) < 0) {
/* There's a read error; kill the connection.*/
if (conn->type == CONN_TYPE_OR) {
connection_or_notify_error(TO_OR_CONN(conn),
socket_error != 0 ?
errno_to_orconn_end_reason(socket_error) :
END_OR_CONN_REASON_CONNRESET,
socket_error != 0 ?
tor_socket_strerror(socket_error) :
"(unknown, errno was 0)");
}
if (CONN_IS_EDGE(conn)) {
edge_connection_t *edge_conn = TO_EDGE_CONN(conn);
connection_edge_end_errno(edge_conn);
if (conn->type == CONN_TYPE_AP && TO_ENTRY_CONN(conn)->socks_request) {
/* broken, don't send a socks reply back */
TO_ENTRY_CONN(conn)->socks_request->has_finished = 1;
}
}
connection_close_immediate(conn); /* Don't flush; connection is dead. */
/*
* This can bypass normal channel checking since we did
* connection_or_notify_error() above.
*/
connection_mark_for_close_internal(conn);
return -1;
}
n_read += buf_datalen(conn->inbuf) - before;
if (CONN_IS_EDGE(conn) && try_to_read != max_to_read) {
/* instruct it not to try to package partial cells. */
if (connection_process_inbuf(conn, 0) < 0) {
return -1;
}
if (!conn->marked_for_close &&
connection_is_reading(conn) &&
!conn->inbuf_reached_eof &&
max_to_read > 0)
goto loop_again; /* try reading again, in case more is here now */
}
/* one last try, packaging partial cells and all. */
if (!conn->marked_for_close &&
connection_process_inbuf(conn, 1) < 0) {
return -1;
}
if (conn->linked_conn) {
/* The other side's handle_write() will never actually get called, so
* we need to invoke the appropriate callbacks ourself. */
connection_t *linked = conn->linked_conn;
if (n_read) {
/* Probably a no-op, since linked conns typically don't count for
* bandwidth rate limiting. But do it anyway so we can keep stats
* accurately. Note that since we read the bytes from conn, and
* we're writing the bytes onto the linked connection, we count
* these as <i>written</i> bytes. */
connection_buckets_decrement(linked, approx_time(), 0, n_read);
if (connection_flushed_some(linked) < 0)
connection_mark_for_close(linked);
if (!connection_wants_to_flush(linked))
connection_finished_flushing(linked);
}
if (!buf_datalen(linked->outbuf) && conn->active_on_link)
connection_stop_reading_from_linked_conn(conn);
}
/* If we hit the EOF, call connection_reached_eof(). */
if (!conn->marked_for_close &&
conn->inbuf_reached_eof &&
connection_reached_eof(conn) < 0) {
return -1;
}
return 0;
}
/* DOCDOC connection_handle_read */
int
connection_handle_read(connection_t *conn)
{
int res;
tor_gettimeofday_cache_clear();
res = connection_handle_read_impl(conn);
return res;
}
/** Pull in new bytes from conn-\>s or conn-\>linked_conn onto conn-\>inbuf,
* either directly or via TLS. Reduce the token buckets by the number of bytes
* read.
*
* If *max_to_read is -1, then decide it ourselves, else go with the
* value passed to us. When returning, if it's changed, subtract the
* number of bytes we read from *max_to_read.
*
* Return -1 if we want to break conn, else return 0.
*/
static int
connection_read_to_buf(connection_t *conn, ssize_t *max_to_read,
int *socket_error)
{
int result;
ssize_t at_most = *max_to_read;
size_t slack_in_buf, more_to_read;
size_t n_read = 0, n_written = 0;
if (at_most == -1) { /* we need to initialize it */
/* how many bytes are we allowed to read? */
at_most = connection_bucket_read_limit(conn, approx_time());
}
slack_in_buf = buf_slack(conn->inbuf);
again:
if ((size_t)at_most > slack_in_buf && slack_in_buf >= 1024) {
more_to_read = at_most - slack_in_buf;
at_most = slack_in_buf;
} else {
more_to_read = 0;
}
if (connection_speaks_cells(conn) &&
conn->state > OR_CONN_STATE_PROXY_HANDSHAKING) {
int pending;
or_connection_t *or_conn = TO_OR_CONN(conn);
size_t initial_size;
if (conn->state == OR_CONN_STATE_TLS_HANDSHAKING ||
conn->state == OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING) {
/* continue handshaking even if global token bucket is empty */
return connection_tls_continue_handshake(or_conn);
}
log_debug(LD_NET,
"%d: starting, inbuf_datalen %ld (%d pending in tls object)."
" at_most %ld.",
(int)conn->s,(long)buf_datalen(conn->inbuf),
tor_tls_get_pending_bytes(or_conn->tls), (long)at_most);
initial_size = buf_datalen(conn->inbuf);
/* else open, or closing */
result = read_to_buf_tls(or_conn->tls, at_most, conn->inbuf);
if (TOR_TLS_IS_ERROR(result) || result == TOR_TLS_CLOSE)
or_conn->tls_error = result;
else
or_conn->tls_error = 0;
switch (result) {
case TOR_TLS_CLOSE:
case TOR_TLS_ERROR_IO:
log_debug(LD_NET,"TLS connection closed %son read. Closing. "
"(Nickname %s, address %s)",
result == TOR_TLS_CLOSE ? "cleanly " : "",
or_conn->nickname ? or_conn->nickname : "not set",
conn->address);
return result;
CASE_TOR_TLS_ERROR_ANY_NONIO:
log_debug(LD_NET,"tls error [%s]. breaking (nickname %s, address %s).",
tor_tls_err_to_string(result),
or_conn->nickname ? or_conn->nickname : "not set",
conn->address);
return result;
case TOR_TLS_WANTWRITE:
connection_start_writing(conn);
return 0;
case TOR_TLS_WANTREAD:
if (conn->in_connection_handle_write) {
/* We've been invoked from connection_handle_write, because we're
* waiting for a TLS renegotiation, the renegotiation started, and
* SSL_read returned WANTWRITE. But now SSL_read is saying WANTREAD
* again. Stop waiting for write events now, or else we'll
* busy-loop until data arrives for us to read. */
connection_stop_writing(conn);
if (!connection_is_reading(conn))
connection_start_reading(conn);
}
/* we're already reading, one hopes */
result = 0;
break;
case TOR_TLS_DONE: /* no data read, so nothing to process */
result = 0;
break; /* so we call bucket_decrement below */
default:
break;
}
pending = tor_tls_get_pending_bytes(or_conn->tls);
if (pending) {
/* If we have any pending bytes, we read them now. This *can*
* take us over our read allotment, but really we shouldn't be
* believing that SSL bytes are the same as TCP bytes anyway. */
int r2 = read_to_buf_tls(or_conn->tls, pending, conn->inbuf);
if (BUG(r2<0)) {
log_warn(LD_BUG, "apparently, reading pending bytes can fail.");
return -1;
}
}
result = (int)(buf_datalen(conn->inbuf)-initial_size);
tor_tls_get_n_raw_bytes(or_conn->tls, &n_read, &n_written);
log_debug(LD_GENERAL, "After TLS read of %d: %ld read, %ld written",
result, (long)n_read, (long)n_written);
} else if (conn->linked) {
if (conn->linked_conn) {
result = move_buf_to_buf(conn->inbuf, conn->linked_conn->outbuf,
&conn->linked_conn->outbuf_flushlen);
} else {
result = 0;
}
//log_notice(LD_GENERAL, "Moved %d bytes on an internal link!", result);
/* If the other side has disappeared, or if it's been marked for close and
* we flushed its outbuf, then we should set our inbuf_reached_eof. */
if (!conn->linked_conn ||
(conn->linked_conn->marked_for_close &&
buf_datalen(conn->linked_conn->outbuf) == 0))
conn->inbuf_reached_eof = 1;
n_read = (size_t) result;
} else {
/* !connection_speaks_cells, !conn->linked_conn. */
int reached_eof = 0;
CONN_LOG_PROTECT(conn,
result = read_to_buf(conn->s, at_most, conn->inbuf, &reached_eof,
socket_error));
if (reached_eof)
conn->inbuf_reached_eof = 1;
// log_fn(LOG_DEBUG,"read_to_buf returned %d.",read_result);
if (result < 0)
return -1;
n_read = (size_t) result;
}
if (n_read > 0) {
/* change *max_to_read */
*max_to_read = at_most - n_read;
/* Update edge_conn->n_read and ocirc->n_read_circ_bw */
if (conn->type == CONN_TYPE_AP) {
edge_connection_t *edge_conn = TO_EDGE_CONN(conn);
circuit_t *circ = circuit_get_by_edge_conn(edge_conn);
origin_circuit_t *ocirc;
/* Check for overflow: */
if (PREDICT_LIKELY(UINT32_MAX - edge_conn->n_read > n_read))
edge_conn->n_read += (int)n_read;
else
edge_conn->n_read = UINT32_MAX;
if (circ && CIRCUIT_IS_ORIGIN(circ)) {
ocirc = TO_ORIGIN_CIRCUIT(circ);
if (PREDICT_LIKELY(UINT32_MAX - ocirc->n_read_circ_bw > n_read))
ocirc->n_read_circ_bw += (int)n_read;
else
ocirc->n_read_circ_bw = UINT32_MAX;
}
}
/* If CONN_BW events are enabled, update conn->n_read_conn_bw for
* OR/DIR/EXIT connections, checking for overflow. */
if (get_options()->TestingEnableConnBwEvent &&
(conn->type == CONN_TYPE_OR ||
conn->type == CONN_TYPE_DIR ||
conn->type == CONN_TYPE_EXIT)) {
if (PREDICT_LIKELY(UINT32_MAX - conn->n_read_conn_bw > n_read))
conn->n_read_conn_bw += (int)n_read;
else
conn->n_read_conn_bw = UINT32_MAX;
}
}
connection_buckets_decrement(conn, approx_time(), n_read, n_written);
if (more_to_read && result == at_most) {
slack_in_buf = buf_slack(conn->inbuf);
at_most = more_to_read;
goto again;
}
/* Call even if result is 0, since the global read bucket may
* have reached 0 on a different conn, and this connection needs to
* know to stop reading. */
connection_consider_empty_read_buckets(conn);
if (n_written > 0 && connection_is_writing(conn))
connection_consider_empty_write_buckets(conn);
return 0;
}
/** A pass-through to fetch_from_buf. */
int
connection_fetch_from_buf(char *string, size_t len, connection_t *conn)
{
return fetch_from_buf(string, len, conn->inbuf);
}
/** As fetch_from_buf_line(), but read from a connection's input buffer. */
int
connection_fetch_from_buf_line(connection_t *conn, char *data,
size_t *data_len)
{
return fetch_from_buf_line(conn->inbuf, data, data_len);
}
/** As fetch_from_buf_http, but fetches from a connection's input buffer_t as
* appropriate. */
int
connection_fetch_from_buf_http(connection_t *conn,
char **headers_out, size_t max_headerlen,
char **body_out, size_t *body_used,
size_t max_bodylen, int force_complete)
{
return fetch_from_buf_http(conn->inbuf, headers_out, max_headerlen,
body_out, body_used, max_bodylen, force_complete);
}
/** Return conn-\>outbuf_flushlen: how many bytes conn wants to flush
* from its outbuf. */
int
connection_wants_to_flush(connection_t *conn)
{
return conn->outbuf_flushlen > 0;
}
/** Are there too many bytes on edge connection <b>conn</b>'s outbuf to
* send back a relay-level sendme yet? Return 1 if so, 0 if not. Used by
* connection_edge_consider_sending_sendme().
*/
int
connection_outbuf_too_full(connection_t *conn)
{
return (conn->outbuf_flushlen > 10*CELL_PAYLOAD_SIZE);
}
/** Try to flush more bytes onto <b>conn</b>-\>s.
*
* This function gets called either from conn_write_callback() in main.c
* when libevent tells us that conn wants to write, or below
* from connection_write_to_buf() when an entire TLS record is ready.
*
* Update <b>conn</b>-\>timestamp_lastwritten to now, and call flush_buf
* or flush_buf_tls appropriately. If it succeeds and there are no more
* more bytes on <b>conn</b>-\>outbuf, then call connection_finished_flushing
* on it too.
*
* If <b>force</b>, then write as many bytes as possible, ignoring bandwidth
* limits. (Used for flushing messages to controller connections on fatal
* errors.)
*
* Mark the connection and return -1 if you want to close it, else
* return 0.
*/
static int
connection_handle_write_impl(connection_t *conn, int force)
{
int e;
socklen_t len=(socklen_t)sizeof(e);
int result;
ssize_t max_to_write;
time_t now = approx_time();
size_t n_read = 0, n_written = 0;
int dont_stop_writing = 0;
tor_assert(!connection_is_listener(conn));
if (conn->marked_for_close || !SOCKET_OK(conn->s))
return 0; /* do nothing */
if (conn->in_flushed_some) {
log_warn(LD_BUG, "called recursively from inside conn->in_flushed_some");
return 0;
}
conn->timestamp_lastwritten = now;
/* Sometimes, "writable" means "connected". */
if (connection_state_is_connecting(conn)) {
if (getsockopt(conn->s, SOL_SOCKET, SO_ERROR, (void*)&e, &len) < 0) {
log_warn(LD_BUG, "getsockopt() syscall failed");
if (conn->type == CONN_TYPE_OR) {
or_connection_t *orconn = TO_OR_CONN(conn);
connection_or_close_for_error(orconn, 0);
} else {
if (CONN_IS_EDGE(conn)) {
connection_edge_end_errno(TO_EDGE_CONN(conn));
}
connection_mark_for_close(conn);
}
return -1;
}
if (e) {
/* some sort of error, but maybe just inprogress still */
if (!ERRNO_IS_CONN_EINPROGRESS(e)) {
log_info(LD_NET,"in-progress connect failed. Removing. (%s)",
tor_socket_strerror(e));
if (CONN_IS_EDGE(conn))
connection_edge_end_errno(TO_EDGE_CONN(conn));
if (conn->type == CONN_TYPE_OR)
connection_or_notify_error(TO_OR_CONN(conn),
errno_to_orconn_end_reason(e),
tor_socket_strerror(e));
connection_close_immediate(conn);
/*
* This can bypass normal channel checking since we did
* connection_or_notify_error() above.
*/
connection_mark_for_close_internal(conn);
return -1;
} else {
return 0; /* no change, see if next time is better */
}
}
/* The connection is successful. */
if (connection_finished_connecting(conn)<0)
return -1;
}
max_to_write = force ? (ssize_t)conn->outbuf_flushlen
: connection_bucket_write_limit(conn, now);
if (connection_speaks_cells(conn) &&
conn->state > OR_CONN_STATE_PROXY_HANDSHAKING) {
or_connection_t *or_conn = TO_OR_CONN(conn);
size_t initial_size;
if (conn->state == OR_CONN_STATE_TLS_HANDSHAKING ||
conn->state == OR_CONN_STATE_TLS_CLIENT_RENEGOTIATING) {
connection_stop_writing(conn);
if (connection_tls_continue_handshake(or_conn) < 0) {
/* Don't flush; connection is dead. */
connection_or_notify_error(or_conn,
END_OR_CONN_REASON_MISC,
"TLS error in connection_tls_"
"continue_handshake()");
connection_close_immediate(conn);
/*
* This can bypass normal channel checking since we did
* connection_or_notify_error() above.
*/
connection_mark_for_close_internal(conn);
return -1;
}
return 0;
} else if (conn->state == OR_CONN_STATE_TLS_SERVER_RENEGOTIATING) {
return connection_handle_read(conn);
}
/* else open, or closing */
initial_size = buf_datalen(conn->outbuf);
result = flush_buf_tls(or_conn->tls, conn->outbuf,
max_to_write, &conn->outbuf_flushlen);
/* If we just flushed the last bytes, tell the channel on the
* or_conn to check if it needs to geoip_change_dirreq_state() */
/* XXXX move this to flushed_some or finished_flushing -NM */
if (buf_datalen(conn->outbuf) == 0 && or_conn->chan)
channel_notify_flushed(TLS_CHAN_TO_BASE(or_conn->chan));
switch (result) {
CASE_TOR_TLS_ERROR_ANY:
case TOR_TLS_CLOSE:
log_info(LD_NET, result != TOR_TLS_CLOSE ?
"tls error. breaking.":"TLS connection closed on flush");
/* Don't flush; connection is dead. */
connection_or_notify_error(or_conn,
END_OR_CONN_REASON_MISC,
result != TOR_TLS_CLOSE ?
"TLS error in during flush" :
"TLS closed during flush");
connection_close_immediate(conn);
/*
* This can bypass normal channel checking since we did
* connection_or_notify_error() above.
*/
connection_mark_for_close_internal(conn);
return -1;
case TOR_TLS_WANTWRITE:
log_debug(LD_NET,"wanted write.");
/* we're already writing */
dont_stop_writing = 1;
break;
case TOR_TLS_WANTREAD:
/* Make sure to avoid a loop if the receive buckets are empty. */
log_debug(LD_NET,"wanted read.");
if (!connection_is_reading(conn)) {
connection_stop_writing(conn);
conn->write_blocked_on_bw = 1;
/* we'll start reading again when we get more tokens in our
* read bucket; then we'll start writing again too.
*/
}
/* else no problem, we're already reading */
return 0;
/* case TOR_TLS_DONE:
* for TOR_TLS_DONE, fall through to check if the flushlen
* is empty, so we can stop writing.
*/
}
tor_tls_get_n_raw_bytes(or_conn->tls, &n_read, &n_written);
log_debug(LD_GENERAL, "After TLS write of %d: %ld read, %ld written",
result, (long)n_read, (long)n_written);
or_conn->bytes_xmitted += result;
or_conn->bytes_xmitted_by_tls += n_written;
/* So we notice bytes were written even on error */
/* XXXX This cast is safe since we can never write INT_MAX bytes in a
* single set of TLS operations. But it looks kinda ugly. If we refactor
* the *_buf_tls functions, we should make them return ssize_t or size_t
* or something. */
result = (int)(initial_size-buf_datalen(conn->outbuf));
} else {
CONN_LOG_PROTECT(conn,
result = flush_buf(conn->s, conn->outbuf,
max_to_write, &conn->outbuf_flushlen));
if (result < 0) {
if (CONN_IS_EDGE(conn))
connection_edge_end_errno(TO_EDGE_CONN(conn));
if (conn->type == CONN_TYPE_AP) {
/* writing failed; we couldn't send a SOCKS reply if we wanted to */
TO_ENTRY_CONN(conn)->socks_request->has_finished = 1;
}
connection_close_immediate(conn); /* Don't flush; connection is dead. */
connection_mark_for_close(conn);
return -1;
}
n_written = (size_t) result;
}
if (n_written && conn->type == CONN_TYPE_AP) {
edge_connection_t *edge_conn = TO_EDGE_CONN(conn);
circuit_t *circ = circuit_get_by_edge_conn(edge_conn);
origin_circuit_t *ocirc;
/* Check for overflow: */
if (PREDICT_LIKELY(UINT32_MAX - edge_conn->n_written > n_written))
edge_conn->n_written += (int)n_written;
else
edge_conn->n_written = UINT32_MAX;
if (circ && CIRCUIT_IS_ORIGIN(circ)) {
ocirc = TO_ORIGIN_CIRCUIT(circ);
if (PREDICT_LIKELY(UINT32_MAX - ocirc->n_written_circ_bw > n_written))
ocirc->n_written_circ_bw += (int)n_written;
else
ocirc->n_written_circ_bw = UINT32_MAX;
}
}
/* If CONN_BW events are enabled, update conn->n_written_conn_bw for
* OR/DIR/EXIT connections, checking for overflow. */
if (n_written && get_options()->TestingEnableConnBwEvent &&
(conn->type == CONN_TYPE_OR ||
conn->type == CONN_TYPE_DIR ||
conn->type == CONN_TYPE_EXIT)) {
if (PREDICT_LIKELY(UINT32_MAX - conn->n_written_conn_bw > n_written))
conn->n_written_conn_bw += (int)n_written;
else
conn->n_written_conn_bw = UINT32_MAX;
}
connection_buckets_decrement(conn, approx_time(), n_read, n_written);
if (result > 0) {
/* If we wrote any bytes from our buffer, then call the appropriate
* functions. */
if (connection_flushed_some(conn) < 0) {
if (connection_speaks_cells(conn)) {
connection_or_notify_error(TO_OR_CONN(conn),
END_OR_CONN_REASON_MISC,
"Got error back from "
"connection_flushed_some()");
}
/*
* This can bypass normal channel checking since we did
* connection_or_notify_error() above.
*/
connection_mark_for_close_internal(conn);
}
}
if (!connection_wants_to_flush(conn) &&
!dont_stop_writing) { /* it's done flushing */
if (connection_finished_flushing(conn) < 0) {
/* already marked */
return -1;
}
return 0;
}
/* Call even if result is 0, since the global write bucket may
* have reached 0 on a different conn, and this connection needs to
* know to stop writing. */
connection_consider_empty_write_buckets(conn);
if (n_read > 0 && connection_is_reading(conn))
connection_consider_empty_read_buckets(conn);
return 0;
}
/* DOCDOC connection_handle_write */
int
connection_handle_write(connection_t *conn, int force)
{
int res;
tor_gettimeofday_cache_clear();
conn->in_connection_handle_write = 1;
res = connection_handle_write_impl(conn, force);
conn->in_connection_handle_write = 0;
return res;
}
/**
* Try to flush data that's waiting for a write on <b>conn</b>. Return
* -1 on failure, 0 on success.
*
* Don't use this function for regular writing; the buffers
* system should be good enough at scheduling writes there. Instead, this
* function is for cases when we're about to exit or something and we want
* to report it right away.
*/
int
connection_flush(connection_t *conn)
{
return connection_handle_write(conn, 1);
}
/** Append <b>len</b> bytes of <b>string</b> onto <b>conn</b>'s
* outbuf, and ask it to start writing.
*
* If <b>zlib</b> is nonzero, this is a directory connection that should get
* its contents compressed or decompressed as they're written. If zlib is
* negative, this is the last data to be compressed, and the connection's zlib
* state should be flushed.
*
* If it's a local control connection and a 64k chunk is ready, try to flush
* it all, so we don't end up with many megabytes of controller info queued at
* once.
*/
MOCK_IMPL(void,
connection_write_to_buf_impl_,(const char *string, size_t len,
connection_t *conn, int zlib))
{
/* XXXX This function really needs to return -1 on failure. */
int r;
size_t old_datalen;
if (!len && !(zlib<0))
return;
/* if it's marked for close, only allow write if we mean to flush it */
if (conn->marked_for_close && !conn->hold_open_until_flushed)
return;
old_datalen = buf_datalen(conn->outbuf);
if (zlib) {
dir_connection_t *dir_conn = TO_DIR_CONN(conn);
int done = zlib < 0;
CONN_LOG_PROTECT(conn, r = write_to_buf_zlib(conn->outbuf,
dir_conn->zlib_state,
string, len, done));
} else {
CONN_LOG_PROTECT(conn, r = write_to_buf(string, len, conn->outbuf));
}
if (r < 0) {
if (CONN_IS_EDGE(conn)) {
/* if it failed, it means we have our package/delivery windows set
wrong compared to our max outbuf size. close the whole circuit. */
log_warn(LD_NET,
"write_to_buf failed. Closing circuit (fd %d).", (int)conn->s);
circuit_mark_for_close(circuit_get_by_edge_conn(TO_EDGE_CONN(conn)),
END_CIRC_REASON_INTERNAL);
} else if (conn->type == CONN_TYPE_OR) {
or_connection_t *orconn = TO_OR_CONN(conn);
log_warn(LD_NET,
"write_to_buf failed on an orconn; notifying of error "
"(fd %d)", (int)(conn->s));
connection_or_close_for_error(orconn, 0);
} else {
log_warn(LD_NET,
"write_to_buf failed. Closing connection (fd %d).",
(int)conn->s);
connection_mark_for_close(conn);
}
return;
}
/* If we receive optimistic data in the EXIT_CONN_STATE_RESOLVING
* state, we don't want to try to write it right away, since
* conn->write_event won't be set yet. Otherwise, write data from
* this conn as the socket is available. */
if (conn->write_event) {
connection_start_writing(conn);
}
if (zlib) {
conn->outbuf_flushlen += buf_datalen(conn->outbuf) - old_datalen;
} else {
conn->outbuf_flushlen += len;
}
}
/** Return a connection_t * from get_connection_array() that satisfies test on
* var, and that is not marked for close. */
#define CONN_GET_TEMPLATE(var, test) \
STMT_BEGIN \
smartlist_t *conns = get_connection_array(); \
SMARTLIST_FOREACH(conns, connection_t *, var, \
{ \
if (var && (test) && !var->marked_for_close) \
return var; \
}); \
return NULL; \
STMT_END
/** Return a connection with given type, address, port, and purpose;
* or NULL if no such connection exists (or if all such connections are marked
* for close). */
MOCK_IMPL(connection_t *,
connection_get_by_type_addr_port_purpose,(int type,
const tor_addr_t *addr, uint16_t port,
int purpose))
{
CONN_GET_TEMPLATE(conn,
(conn->type == type &&
tor_addr_eq(&conn->addr, addr) &&
conn->port == port &&
conn->purpose == purpose));
}
/** Return the stream with id <b>id</b> if it is not already marked for
* close.
*/
connection_t *
connection_get_by_global_id(uint64_t id)
{
CONN_GET_TEMPLATE(conn, conn->global_identifier == id);
}
/** Return a connection of type <b>type</b> that is not marked for close.
*/
connection_t *
connection_get_by_type(int type)
{
CONN_GET_TEMPLATE(conn, conn->type == type);
}
/** Return a connection of type <b>type</b> that is in state <b>state</b>,
* and that is not marked for close.
*/
connection_t *
connection_get_by_type_state(int type, int state)
{
CONN_GET_TEMPLATE(conn, conn->type == type && conn->state == state);
}
/** Return a connection of type <b>type</b> that has rendquery equal
* to <b>rendquery</b>, and that is not marked for close. If state
* is non-zero, conn must be of that state too.
*/
connection_t *
connection_get_by_type_state_rendquery(int type, int state,
const char *rendquery)
{
tor_assert(type == CONN_TYPE_DIR ||
type == CONN_TYPE_AP || type == CONN_TYPE_EXIT);
tor_assert(rendquery);
CONN_GET_TEMPLATE(conn,
(conn->type == type &&
(!state || state == conn->state)) &&
(
(type == CONN_TYPE_DIR &&
TO_DIR_CONN(conn)->rend_data &&
!rend_cmp_service_ids(rendquery,
TO_DIR_CONN(conn)->rend_data->onion_address))
||
(CONN_IS_EDGE(conn) &&
TO_EDGE_CONN(conn)->rend_data &&
!rend_cmp_service_ids(rendquery,
TO_EDGE_CONN(conn)->rend_data->onion_address))
));
}
/** Return a new smartlist of dir_connection_t * from get_connection_array()
* that satisfy conn_test on connection_t *conn_var, and dirconn_test on
* dir_connection_t *dirconn_var. conn_var must be of CONN_TYPE_DIR and not
* marked for close to be included in the list. */
#define DIR_CONN_LIST_TEMPLATE(conn_var, conn_test, \
dirconn_var, dirconn_test) \
STMT_BEGIN \
smartlist_t *conns = get_connection_array(); \
smartlist_t *dir_conns = smartlist_new(); \
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn_var) { \
if (conn_var && (conn_test) \
&& conn_var->type == CONN_TYPE_DIR \
&& !conn_var->marked_for_close) { \
dir_connection_t *dirconn_var = TO_DIR_CONN(conn_var); \
if (dirconn_var && (dirconn_test)) { \
smartlist_add(dir_conns, dirconn_var); \
} \
} \
} SMARTLIST_FOREACH_END(conn_var); \
return dir_conns; \
STMT_END
/** Return a list of directory connections that are fetching the item
* described by <b>purpose</b>/<b>resource</b>. If there are none,
* return an empty list. This list must be freed using smartlist_free,
* but the pointers in it must not be freed.
* Note that this list should not be cached, as the pointers in it can be
* freed if their connections close. */
smartlist_t *
connection_dir_list_by_purpose_and_resource(
int purpose,
const char *resource)
{
DIR_CONN_LIST_TEMPLATE(conn,
conn->purpose == purpose,
dirconn,
0 == strcmp_opt(resource,
dirconn->requested_resource));
}
/** Return a list of directory connections that are fetching the item
* described by <b>purpose</b>/<b>resource</b>/<b>state</b>. If there are
* none, return an empty list. This list must be freed using smartlist_free,
* but the pointers in it must not be freed.
* Note that this list should not be cached, as the pointers in it can be
* freed if their connections close. */
smartlist_t *
connection_dir_list_by_purpose_resource_and_state(
int purpose,
const char *resource,
int state)
{
DIR_CONN_LIST_TEMPLATE(conn,
conn->purpose == purpose && conn->state == state,
dirconn,
0 == strcmp_opt(resource,
dirconn->requested_resource));
}
#undef DIR_CONN_LIST_TEMPLATE
/** Return an arbitrary active OR connection that isn't <b>this_conn</b>.
*
* We use this to guess if we should tell the controller that we
* didn't manage to connect to any of our bridges. */
static connection_t *
connection_get_another_active_or_conn(const or_connection_t *this_conn)
{
CONN_GET_TEMPLATE(conn,
conn != TO_CONN(this_conn) && conn->type == CONN_TYPE_OR);
}
/** Return 1 if there are any active OR connections apart from
* <b>this_conn</b>.
*
* We use this to guess if we should tell the controller that we
* didn't manage to connect to any of our bridges. */
int
any_other_active_or_conns(const or_connection_t *this_conn)
{
connection_t *conn = connection_get_another_active_or_conn(this_conn);
if (conn != NULL) {
log_debug(LD_DIR, "%s: Found an OR connection: %s",
__func__, conn->address);
return 1;
}
return 0;
}
#undef CONN_GET_TEMPLATE
/** Return 1 if <b>conn</b> is a listener conn, else return 0. */
int
connection_is_listener(connection_t *conn)
{
if (conn->type == CONN_TYPE_OR_LISTENER ||
conn->type == CONN_TYPE_EXT_OR_LISTENER ||
conn->type == CONN_TYPE_AP_LISTENER ||
conn->type == CONN_TYPE_AP_TRANS_LISTENER ||
conn->type == CONN_TYPE_AP_DNS_LISTENER ||
conn->type == CONN_TYPE_AP_NATD_LISTENER ||
conn->type == CONN_TYPE_DIR_LISTENER ||
conn->type == CONN_TYPE_CONTROL_LISTENER)
return 1;
return 0;
}
/** Return 1 if <b>conn</b> is in state "open" and is not marked
* for close, else return 0.
*/
int
connection_state_is_open(connection_t *conn)
{
tor_assert(conn);
if (conn->marked_for_close)
return 0;
if ((conn->type == CONN_TYPE_OR && conn->state == OR_CONN_STATE_OPEN) ||
(conn->type == CONN_TYPE_EXT_OR) ||
(conn->type == CONN_TYPE_AP && conn->state == AP_CONN_STATE_OPEN) ||
(conn->type == CONN_TYPE_EXIT && conn->state == EXIT_CONN_STATE_OPEN) ||
(conn->type == CONN_TYPE_CONTROL &&
conn->state == CONTROL_CONN_STATE_OPEN))
return 1;
return 0;
}
/** Return 1 if conn is in 'connecting' state, else return 0. */
int
connection_state_is_connecting(connection_t *conn)
{
tor_assert(conn);
if (conn->marked_for_close)
return 0;
switch (conn->type)
{
case CONN_TYPE_OR:
return conn->state == OR_CONN_STATE_CONNECTING;
case CONN_TYPE_EXIT:
return conn->state == EXIT_CONN_STATE_CONNECTING;
case CONN_TYPE_DIR:
return conn->state == DIR_CONN_STATE_CONNECTING;
}
return 0;
}
/** Allocates a base64'ed authenticator for use in http or https
* auth, based on the input string <b>authenticator</b>. Returns it
* if success, else returns NULL. */
char *
alloc_http_authenticator(const char *authenticator)
{
/* an authenticator in Basic authentication
* is just the string "username:password" */
const size_t authenticator_length = strlen(authenticator);
const size_t base64_authenticator_length =
base64_encode_size(authenticator_length, 0) + 1;
char *base64_authenticator = tor_malloc(base64_authenticator_length);
if (base64_encode(base64_authenticator, base64_authenticator_length,
authenticator, authenticator_length, 0) < 0) {
tor_free(base64_authenticator); /* free and set to null */
}
return base64_authenticator;
}
/** Given a socket handle, check whether the local address (sockname) of the
* socket is one that we've connected from before. If so, double-check
* whether our address has changed and we need to generate keys. If we do,
* call init_keys().
*/
static void
client_check_address_changed(tor_socket_t sock)
{
struct sockaddr_storage out_sockaddr;
socklen_t out_addr_len = (socklen_t) sizeof(out_sockaddr);
tor_addr_t out_addr, iface_addr;
tor_addr_t **last_interface_ip_ptr;
sa_family_t family;
if (!outgoing_addrs)
outgoing_addrs = smartlist_new();
if (getsockname(sock, (struct sockaddr*)&out_sockaddr, &out_addr_len)<0) {
int e = tor_socket_errno(sock);
log_warn(LD_NET, "getsockname() to check for address change failed: %s",
tor_socket_strerror(e));
return;
}
tor_addr_from_sockaddr(&out_addr, (struct sockaddr*)&out_sockaddr, NULL);
family = tor_addr_family(&out_addr);
if (family == AF_INET)
last_interface_ip_ptr = &last_interface_ipv4;
else if (family == AF_INET6)
last_interface_ip_ptr = &last_interface_ipv6;
else
return;
if (! *last_interface_ip_ptr) {
tor_addr_t *a = tor_malloc_zero(sizeof(tor_addr_t));
if (get_interface_address6(LOG_INFO, family, a)==0) {
*last_interface_ip_ptr = a;
} else {
tor_free(a);
}
}
/* If we've used this address previously, we're okay. */
SMARTLIST_FOREACH(outgoing_addrs, const tor_addr_t *, a_ptr,
if (tor_addr_eq(a_ptr, &out_addr))
return;
);
/* Uh-oh. We haven't connected from this address before. Has the interface
* address changed? */
if (get_interface_address6(LOG_INFO, family, &iface_addr)<0)
return;
if (tor_addr_eq(&iface_addr, *last_interface_ip_ptr)) {
/* Nope, it hasn't changed. Add this address to the list. */
smartlist_add(outgoing_addrs, tor_memdup(&out_addr, sizeof(tor_addr_t)));
} else {
/* The interface changed. We're a client, so we need to regenerate our
* keys. First, reset the state. */
log_notice(LD_NET, "Our IP address has changed. Rotating keys...");
tor_addr_copy(*last_interface_ip_ptr, &iface_addr);
SMARTLIST_FOREACH(outgoing_addrs, tor_addr_t*, a_ptr, tor_free(a_ptr));
smartlist_clear(outgoing_addrs);
smartlist_add(outgoing_addrs, tor_memdup(&out_addr, sizeof(tor_addr_t)));
/* We'll need to resolve ourselves again. */
reset_last_resolved_addr();
/* Okay, now change our keys. */
ip_address_changed(1);
}
}
/** Some systems have limited system buffers for recv and xmit on
* sockets allocated in a virtual server or similar environment. For a Tor
* server this can produce the "Error creating network socket: No buffer
* space available" error once all available TCP buffer space is consumed.
* This method will attempt to constrain the buffers allocated for the socket
* to the desired size to stay below system TCP buffer limits.
*/
static void
set_constrained_socket_buffers(tor_socket_t sock, int size)
{
void *sz = (void*)&size;
socklen_t sz_sz = (socklen_t) sizeof(size);
if (setsockopt(sock, SOL_SOCKET, SO_SNDBUF, sz, sz_sz) < 0) {
int e = tor_socket_errno(sock);
log_warn(LD_NET, "setsockopt() to constrain send "
"buffer to %d bytes failed: %s", size, tor_socket_strerror(e));
}
if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, sz, sz_sz) < 0) {
int e = tor_socket_errno(sock);
log_warn(LD_NET, "setsockopt() to constrain recv "
"buffer to %d bytes failed: %s", size, tor_socket_strerror(e));
}
}
/** Process new bytes that have arrived on conn-\>inbuf.
*
* This function just passes conn to the connection-specific
* connection_*_process_inbuf() function. It also passes in
* package_partial if wanted.
*/
static int
connection_process_inbuf(connection_t *conn, int package_partial)
{
tor_assert(conn);
switch (conn->type) {
case CONN_TYPE_OR:
return connection_or_process_inbuf(TO_OR_CONN(conn));
case CONN_TYPE_EXT_OR:
return connection_ext_or_process_inbuf(TO_OR_CONN(conn));
case CONN_TYPE_EXIT:
case CONN_TYPE_AP:
return connection_edge_process_inbuf(TO_EDGE_CONN(conn),
package_partial);
case CONN_TYPE_DIR:
return connection_dir_process_inbuf(TO_DIR_CONN(conn));
case CONN_TYPE_CONTROL:
return connection_control_process_inbuf(TO_CONTROL_CONN(conn));
default:
log_err(LD_BUG,"got unexpected conn type %d.", conn->type);
tor_fragile_assert();
return -1;
}
}
/** Called whenever we've written data on a connection. */
static int
connection_flushed_some(connection_t *conn)
{
int r = 0;
tor_assert(!conn->in_flushed_some);
conn->in_flushed_some = 1;
if (conn->type == CONN_TYPE_DIR &&
conn->state == DIR_CONN_STATE_SERVER_WRITING) {
r = connection_dirserv_flushed_some(TO_DIR_CONN(conn));
} else if (conn->type == CONN_TYPE_OR) {
r = connection_or_flushed_some(TO_OR_CONN(conn));
} else if (CONN_IS_EDGE(conn)) {
r = connection_edge_flushed_some(TO_EDGE_CONN(conn));
}
conn->in_flushed_some = 0;
return r;
}
/** We just finished flushing bytes to the appropriately low network layer,
* and there are no more bytes remaining in conn-\>outbuf or
* conn-\>tls to be flushed.
*
* This function just passes conn to the connection-specific
* connection_*_finished_flushing() function.
*/
static int
connection_finished_flushing(connection_t *conn)
{
tor_assert(conn);
/* If the connection is closed, don't try to do anything more here. */
if (CONN_IS_CLOSED(conn))
return 0;
// log_fn(LOG_DEBUG,"entered. Socket %u.", conn->s);
connection_stop_writing(conn);
switch (conn->type) {
case CONN_TYPE_OR:
return connection_or_finished_flushing(TO_OR_CONN(conn));
case CONN_TYPE_EXT_OR:
return connection_ext_or_finished_flushing(TO_OR_CONN(conn));
case CONN_TYPE_AP:
case CONN_TYPE_EXIT:
return connection_edge_finished_flushing(TO_EDGE_CONN(conn));
case CONN_TYPE_DIR:
return connection_dir_finished_flushing(TO_DIR_CONN(conn));
case CONN_TYPE_CONTROL:
return connection_control_finished_flushing(TO_CONTROL_CONN(conn));
default:
log_err(LD_BUG,"got unexpected conn type %d.", conn->type);
tor_fragile_assert();
return -1;
}
}
/** Called when our attempt to connect() to another server has just
* succeeded.
*
* This function just passes conn to the connection-specific
* connection_*_finished_connecting() function.
*/
static int
connection_finished_connecting(connection_t *conn)
{
tor_assert(conn);
if (!server_mode(get_options())) {
/* See whether getsockname() says our address changed. We need to do this
* now that the connection has finished, because getsockname() on Windows
* won't work until then. */
client_check_address_changed(conn->s);
}
switch (conn->type)
{
case CONN_TYPE_OR:
return connection_or_finished_connecting(TO_OR_CONN(conn));
case CONN_TYPE_EXIT:
return connection_edge_finished_connecting(TO_EDGE_CONN(conn));
case CONN_TYPE_DIR:
return connection_dir_finished_connecting(TO_DIR_CONN(conn));
default:
log_err(LD_BUG,"got unexpected conn type %d.", conn->type);
tor_fragile_assert();
return -1;
}
}
/** Callback: invoked when a connection reaches an EOF event. */
static int
connection_reached_eof(connection_t *conn)
{
switch (conn->type) {
case CONN_TYPE_OR:
case CONN_TYPE_EXT_OR:
return connection_or_reached_eof(TO_OR_CONN(conn));
case CONN_TYPE_AP:
case CONN_TYPE_EXIT:
return connection_edge_reached_eof(TO_EDGE_CONN(conn));
case CONN_TYPE_DIR:
return connection_dir_reached_eof(TO_DIR_CONN(conn));
case CONN_TYPE_CONTROL:
return connection_control_reached_eof(TO_CONTROL_CONN(conn));
default:
log_err(LD_BUG,"got unexpected conn type %d.", conn->type);
tor_fragile_assert();
return -1;
}
}
/** Comparator for the two-orconn case in OOS victim sort */
static int
oos_victim_comparator_for_orconns(or_connection_t *a, or_connection_t *b)
{
int a_circs, b_circs;
/* Fewer circuits == higher priority for OOS kill, sort earlier */
a_circs = connection_or_get_num_circuits(a);
b_circs = connection_or_get_num_circuits(b);
if (a_circs < b_circs) return 1;
else if (a_circs > b_circs) return -1;
else return 0;
}
/** Sort comparator for OOS victims; better targets sort before worse
* ones. */
static int
oos_victim_comparator(const void **a_v, const void **b_v)
{
connection_t *a = NULL, *b = NULL;
/* Get connection pointers out */
a = (connection_t *)(*a_v);
b = (connection_t *)(*b_v);
tor_assert(a != NULL);
tor_assert(b != NULL);
/*
* We always prefer orconns as victims currently; we won't even see
* these non-orconn cases, but if we do, sort them after orconns.
*/
if (a->type == CONN_TYPE_OR && b->type == CONN_TYPE_OR) {
return oos_victim_comparator_for_orconns(TO_OR_CONN(a), TO_OR_CONN(b));
} else {
/*
* One isn't an orconn; if one is, it goes first. We currently have no
* opinions about cases where neither is an orconn.
*/
if (a->type == CONN_TYPE_OR) return -1;
else if (b->type == CONN_TYPE_OR) return 1;
else return 0;
}
}
/** Pick n victim connections for the OOS handler and return them in a
* smartlist.
*/
MOCK_IMPL(STATIC smartlist_t *,
pick_oos_victims, (int n))
{
smartlist_t *eligible = NULL, *victims = NULL;
smartlist_t *conns;
int conn_counts_by_type[CONN_TYPE_MAX_ + 1], i;
/*
* Big damn assumption (someone improve this someday!):
*
* Socket exhaustion normally happens on high-volume relays, and so
* most of the connections involved are orconns. We should pick victims
* by assembling a list of all orconns, and sorting them in order of
* how much 'damage' by some metric we'd be doing by dropping them.
*
* If we move on from orconns, we should probably think about incoming
* directory connections next, or exit connections. Things we should
* probably never kill are controller connections and listeners.
*
* This function will count how many connections of different types
* exist and log it for purposes of gathering data on typical OOS
* situations to guide future improvements.
*/
/* First, get the connection array */
conns = get_connection_array();
/*
* Iterate it and pick out eligible connection types, and log some stats
* along the way.
*/
eligible = smartlist_new();
memset(conn_counts_by_type, 0, sizeof(conn_counts_by_type));
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, c) {
/* Bump the counter */
tor_assert(c->type <= CONN_TYPE_MAX_);
++(conn_counts_by_type[c->type]);
/* Skip anything without a socket we can free */
if (!(SOCKET_OK(c->s))) {
continue;
}
/* Skip anything we would count as moribund */
if (connection_is_moribund(c)) {
continue;
}
switch (c->type) {
case CONN_TYPE_OR:
/* We've got an orconn, it's eligible to be OOSed */
smartlist_add(eligible, c);
break;
default:
/* We don't know what to do with it, ignore it */
break;
}
} SMARTLIST_FOREACH_END(c);
/* Log some stats */
if (smartlist_len(conns) > 0) {
/* At least one counter must be non-zero */
log_info(LD_NET, "Some stats on conn types seen during OOS follow");
for (i = CONN_TYPE_MIN_; i <= CONN_TYPE_MAX_; ++i) {
/* Did we see any? */
if (conn_counts_by_type[i] > 0) {
log_info(LD_NET, "%s: %d conns",
conn_type_to_string(i),
conn_counts_by_type[i]);
}
}
log_info(LD_NET, "Done with OOS conn type stats");
}
/* Did we find more eligible targets than we want to kill? */
if (smartlist_len(eligible) > n) {
/* Sort the list in order of target preference */
smartlist_sort(eligible, oos_victim_comparator);
/* Pick first n as victims */
victims = smartlist_new();
for (i = 0; i < n; ++i) {
smartlist_add(victims, smartlist_get(eligible, i));
}
/* Free the original list */
smartlist_free(eligible);
} else {
/* No, we can just call them all victims */
victims = eligible;
}
return victims;
}
/** Kill a list of connections for the OOS handler. */
MOCK_IMPL(STATIC void,
kill_conn_list_for_oos, (smartlist_t *conns))
{
if (!conns) return;
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, c) {
/* Make sure the channel layer gets told about orconns */
if (c->type == CONN_TYPE_OR) {
connection_or_close_for_error(TO_OR_CONN(c), 1);
} else {
connection_mark_for_close(c);
}
} SMARTLIST_FOREACH_END(c);
log_notice(LD_NET,
"OOS handler marked %d connections",
smartlist_len(conns));
}
/** Out-of-Sockets handler; n_socks is the current number of open
* sockets, and failed is non-zero if a socket exhaustion related
* error immediately preceded this call. This is where to do
* circuit-killing heuristics as needed.
*/
void
connection_check_oos(int n_socks, int failed)
{
int target_n_socks = 0, moribund_socks, socks_to_kill;
smartlist_t *conns;
/* Early exit: is OOS checking disabled? */
if (get_options()->DisableOOSCheck) {
return;
}
/* Sanity-check args */
tor_assert(n_socks >= 0);
/*
* Make some log noise; keep it at debug level since this gets a chance
* to run on every connection attempt.
*/
log_debug(LD_NET,
"Running the OOS handler (%d open sockets, %s)",
n_socks, (failed != 0) ? "exhaustion seen" : "no exhaustion");
/*
* Check if we're really handling an OOS condition, and if so decide how
* many sockets we want to get down to. Be sure we check if the threshold
* is distinct from zero first; it's possible for this to be called a few
* times before we've finished reading the config.
*/
if (n_socks >= get_options()->ConnLimit_high_thresh &&
get_options()->ConnLimit_high_thresh != 0 &&
get_options()->ConnLimit_ != 0) {
/* Try to get down to the low threshold */
target_n_socks = get_options()->ConnLimit_low_thresh;
log_notice(LD_NET,
"Current number of sockets %d is greater than configured "
"limit %d; OOS handler trying to get down to %d",
n_socks, get_options()->ConnLimit_high_thresh,
target_n_socks);
} else if (failed) {
/*
* If we're not at the limit but we hit a socket exhaustion error, try to
* drop some (but not as aggressively as ConnLimit_low_threshold, which is
* 3/4 of ConnLimit_)
*/
target_n_socks = (n_socks * 9) / 10;
log_notice(LD_NET,
"We saw socket exhaustion at %d open sockets; OOS handler "
"trying to get down to %d",
n_socks, target_n_socks);
}
if (target_n_socks > 0) {
/*
* It's an OOS!
*
* Count moribund sockets; it's be important that anything we decide
* to get rid of here but don't immediately close get counted as moribund
* on subsequent invocations so we don't try to kill too many things if
* connection_check_oos() gets called multiple times.
*/
moribund_socks = connection_count_moribund();
if (moribund_socks < n_socks - target_n_socks) {
socks_to_kill = n_socks - target_n_socks - moribund_socks;
conns = pick_oos_victims(socks_to_kill);
if (conns) {
kill_conn_list_for_oos(conns);
log_notice(LD_NET,
"OOS handler killed %d conns", smartlist_len(conns));
smartlist_free(conns);
} else {
log_notice(LD_NET, "OOS handler failed to pick any victim conns");
}
} else {
log_notice(LD_NET,
"Not killing any sockets for OOS because there are %d "
"already moribund, and we only want to eliminate %d",
moribund_socks, n_socks - target_n_socks);
}
}
}
/** Log how many bytes are used by buffers of different kinds and sizes. */
void
connection_dump_buffer_mem_stats(int severity)
{
uint64_t used_by_type[CONN_TYPE_MAX_+1];
uint64_t alloc_by_type[CONN_TYPE_MAX_+1];
int n_conns_by_type[CONN_TYPE_MAX_+1];
uint64_t total_alloc = 0;
uint64_t total_used = 0;
int i;
smartlist_t *conns = get_connection_array();
memset(used_by_type, 0, sizeof(used_by_type));
memset(alloc_by_type, 0, sizeof(alloc_by_type));
memset(n_conns_by_type, 0, sizeof(n_conns_by_type));
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, c) {
int tp = c->type;
++n_conns_by_type[tp];
if (c->inbuf) {
used_by_type[tp] += buf_datalen(c->inbuf);
alloc_by_type[tp] += buf_allocation(c->inbuf);
}
if (c->outbuf) {
used_by_type[tp] += buf_datalen(c->outbuf);
alloc_by_type[tp] += buf_allocation(c->outbuf);
}
} SMARTLIST_FOREACH_END(c);
for (i=0; i <= CONN_TYPE_MAX_; ++i) {
total_used += used_by_type[i];
total_alloc += alloc_by_type[i];
}
tor_log(severity, LD_GENERAL,
"In buffers for %d connections: "U64_FORMAT" used/"U64_FORMAT" allocated",
smartlist_len(conns),
U64_PRINTF_ARG(total_used), U64_PRINTF_ARG(total_alloc));
for (i=CONN_TYPE_MIN_; i <= CONN_TYPE_MAX_; ++i) {
if (!n_conns_by_type[i])
continue;
tor_log(severity, LD_GENERAL,
" For %d %s connections: "U64_FORMAT" used/"U64_FORMAT" allocated",
n_conns_by_type[i], conn_type_to_string(i),
U64_PRINTF_ARG(used_by_type[i]), U64_PRINTF_ARG(alloc_by_type[i]));
}
}
/** Verify that connection <b>conn</b> has all of its invariants
* correct. Trigger an assert if anything is invalid.
*/
void
assert_connection_ok(connection_t *conn, time_t now)
{
(void) now; /* XXXX unused. */
tor_assert(conn);
tor_assert(conn->type >= CONN_TYPE_MIN_);
tor_assert(conn->type <= CONN_TYPE_MAX_);
switch (conn->type) {
case CONN_TYPE_OR:
case CONN_TYPE_EXT_OR:
tor_assert(conn->magic == OR_CONNECTION_MAGIC);
break;
case CONN_TYPE_AP:
tor_assert(conn->magic == ENTRY_CONNECTION_MAGIC);
break;
case CONN_TYPE_EXIT:
tor_assert(conn->magic == EDGE_CONNECTION_MAGIC);
break;
case CONN_TYPE_DIR:
tor_assert(conn->magic == DIR_CONNECTION_MAGIC);
break;
case CONN_TYPE_CONTROL:
tor_assert(conn->magic == CONTROL_CONNECTION_MAGIC);
break;
CASE_ANY_LISTENER_TYPE:
tor_assert(conn->magic == LISTENER_CONNECTION_MAGIC);
break;
default:
tor_assert(conn->magic == BASE_CONNECTION_MAGIC);
break;
}
if (conn->linked_conn) {
tor_assert(conn->linked_conn->linked_conn == conn);
tor_assert(conn->linked);
}
if (conn->linked)
tor_assert(!SOCKET_OK(conn->s));
if (conn->outbuf_flushlen > 0) {
/* With optimistic data, we may have queued data in
* EXIT_CONN_STATE_RESOLVING while the conn is not yet marked to writing.
* */
tor_assert((conn->type == CONN_TYPE_EXIT &&
conn->state == EXIT_CONN_STATE_RESOLVING) ||
connection_is_writing(conn) ||
conn->write_blocked_on_bw ||
(CONN_IS_EDGE(conn) &&
TO_EDGE_CONN(conn)->edge_blocked_on_circ));
}
if (conn->hold_open_until_flushed)
tor_assert(conn->marked_for_close);
/* XXXX check: read_blocked_on_bw, write_blocked_on_bw, s, conn_array_index,
* marked_for_close. */
/* buffers */
if (conn->inbuf)
assert_buf_ok(conn->inbuf);
if (conn->outbuf)
assert_buf_ok(conn->outbuf);
if (conn->type == CONN_TYPE_OR) {
or_connection_t *or_conn = TO_OR_CONN(conn);
if (conn->state == OR_CONN_STATE_OPEN) {
/* tor_assert(conn->bandwidth > 0); */
/* the above isn't necessarily true: if we just did a TLS
* handshake but we didn't recognize the other peer, or it
* gave a bad cert/etc, then we won't have assigned bandwidth,
* yet it will be open. -RD
*/
// tor_assert(conn->read_bucket >= 0);
}
// tor_assert(conn->addr && conn->port);
tor_assert(conn->address);
if (conn->state > OR_CONN_STATE_PROXY_HANDSHAKING)
tor_assert(or_conn->tls);
}
if (CONN_IS_EDGE(conn)) {
/* XXX unchecked: package window, deliver window. */
if (conn->type == CONN_TYPE_AP) {
entry_connection_t *entry_conn = TO_ENTRY_CONN(conn);
if (entry_conn->chosen_exit_optional || entry_conn->chosen_exit_retries)
tor_assert(entry_conn->chosen_exit_name);
tor_assert(entry_conn->socks_request);
if (conn->state == AP_CONN_STATE_OPEN) {
tor_assert(entry_conn->socks_request->has_finished);
if (!conn->marked_for_close) {
tor_assert(ENTRY_TO_EDGE_CONN(entry_conn)->cpath_layer);
assert_cpath_layer_ok(ENTRY_TO_EDGE_CONN(entry_conn)->cpath_layer);
}
}
}
if (conn->type == CONN_TYPE_EXIT) {
tor_assert(conn->purpose == EXIT_PURPOSE_CONNECT ||
conn->purpose == EXIT_PURPOSE_RESOLVE);
}
} else if (conn->type == CONN_TYPE_DIR) {
} else {
/* Purpose is only used for dir and exit types currently */
tor_assert(!conn->purpose);
}
switch (conn->type)
{
CASE_ANY_LISTENER_TYPE:
tor_assert(conn->state == LISTENER_STATE_READY);
break;
case CONN_TYPE_OR:
tor_assert(conn->state >= OR_CONN_STATE_MIN_);
tor_assert(conn->state <= OR_CONN_STATE_MAX_);
break;
case CONN_TYPE_EXT_OR:
tor_assert(conn->state >= EXT_OR_CONN_STATE_MIN_);
tor_assert(conn->state <= EXT_OR_CONN_STATE_MAX_);
break;
case CONN_TYPE_EXIT:
tor_assert(conn->state >= EXIT_CONN_STATE_MIN_);
tor_assert(conn->state <= EXIT_CONN_STATE_MAX_);
tor_assert(conn->purpose >= EXIT_PURPOSE_MIN_);
tor_assert(conn->purpose <= EXIT_PURPOSE_MAX_);
break;
case CONN_TYPE_AP:
tor_assert(conn->state >= AP_CONN_STATE_MIN_);
tor_assert(conn->state <= AP_CONN_STATE_MAX_);
tor_assert(TO_ENTRY_CONN(conn)->socks_request);
break;
case CONN_TYPE_DIR:
tor_assert(conn->state >= DIR_CONN_STATE_MIN_);
tor_assert(conn->state <= DIR_CONN_STATE_MAX_);
tor_assert(conn->purpose >= DIR_PURPOSE_MIN_);
tor_assert(conn->purpose <= DIR_PURPOSE_MAX_);
break;
case CONN_TYPE_CONTROL:
tor_assert(conn->state >= CONTROL_CONN_STATE_MIN_);
tor_assert(conn->state <= CONTROL_CONN_STATE_MAX_);
break;
default:
tor_assert(0);
}
}
/** Fills <b>addr</b> and <b>port</b> with the details of the global
* proxy server we are using.
* <b>conn</b> contains the connection we are using the proxy for.
*
* Return 0 on success, -1 on failure.
*/
int
get_proxy_addrport(tor_addr_t *addr, uint16_t *port, int *proxy_type,
const connection_t *conn)
{
const or_options_t *options = get_options();
/* Client Transport Plugins can use another proxy, but that should be hidden
* from the rest of tor (as the plugin is responsible for dealing with the
* proxy), check it first, then check the rest of the proxy types to allow
* the config to have unused ClientTransportPlugin entries.
*/
if (options->ClientTransportPlugin) {
const transport_t *transport = NULL;
int r;
r = get_transport_by_bridge_addrport(&conn->addr, conn->port, &transport);
if (r<0)
return -1;
if (transport) { /* transport found */
tor_addr_copy(addr, &transport->addr);
*port = transport->port;
*proxy_type = transport->socks_version;
return 0;
}
/* Unused ClientTransportPlugin. */
}
if (options->HTTPSProxy) {
tor_addr_copy(addr, &options->HTTPSProxyAddr);
*port = options->HTTPSProxyPort;
*proxy_type = PROXY_CONNECT;
return 0;
} else if (options->Socks4Proxy) {
tor_addr_copy(addr, &options->Socks4ProxyAddr);
*port = options->Socks4ProxyPort;
*proxy_type = PROXY_SOCKS4;
return 0;
} else if (options->Socks5Proxy) {
tor_addr_copy(addr, &options->Socks5ProxyAddr);
*port = options->Socks5ProxyPort;
*proxy_type = PROXY_SOCKS5;
return 0;
}
tor_addr_make_unspec(addr);
*port = 0;
*proxy_type = PROXY_NONE;
return 0;
}
/** Log a failed connection to a proxy server.
* <b>conn</b> is the connection we use the proxy server for. */
void
log_failed_proxy_connection(connection_t *conn)
{
tor_addr_t proxy_addr;
uint16_t proxy_port;
int proxy_type;
if (get_proxy_addrport(&proxy_addr, &proxy_port, &proxy_type, conn) != 0)
return; /* if we have no proxy set up, leave this function. */
log_warn(LD_NET,
"The connection to the %s proxy server at %s just failed. "
"Make sure that the proxy server is up and running.",
proxy_type_to_string(proxy_type),
fmt_addrport(&proxy_addr, proxy_port));
}
/** Return string representation of <b>proxy_type</b>. */
static const char *
proxy_type_to_string(int proxy_type)
{
switch (proxy_type) {
case PROXY_CONNECT: return "HTTP";
case PROXY_SOCKS4: return "SOCKS4";
case PROXY_SOCKS5: return "SOCKS5";
case PROXY_PLUGGABLE: return "pluggable transports SOCKS";
case PROXY_NONE: return "NULL";
default: tor_assert(0);
}
return NULL; /*Unreached*/
}
/** Call connection_free_() on every connection in our array, and release all
* storage held by connection.c.
*
* Don't do the checks in connection_free(), because they will
* fail.
*/
void
connection_free_all(void)
{
smartlist_t *conns = get_connection_array();
/* We don't want to log any messages to controllers. */
SMARTLIST_FOREACH(conns, connection_t *, conn,
if (conn->type == CONN_TYPE_CONTROL)
TO_CONTROL_CONN(conn)->event_mask = 0);
control_update_global_event_mask();
/* Unlink everything from the identity map. */
connection_or_clear_identity_map();
connection_or_clear_ext_or_id_map();
/* Clear out our list of broken connections */
clear_broken_connection_map(0);
SMARTLIST_FOREACH(conns, connection_t *, conn, connection_free_(conn));
if (outgoing_addrs) {
SMARTLIST_FOREACH(outgoing_addrs, tor_addr_t *, addr, tor_free(addr));
smartlist_free(outgoing_addrs);
outgoing_addrs = NULL;
}
tor_free(last_interface_ipv4);
tor_free(last_interface_ipv6);
}
/** Log a warning, and possibly emit a control event, that <b>received</b> came
* at a skewed time. <b>trusted</b> indicates that the <b>source</b> was one
* that we had more faith in and therefore the warning level should have higher
* severity.
*/
void
clock_skew_warning(const connection_t *conn, long apparent_skew, int trusted,
log_domain_mask_t domain, const char *received,
const char *source)
{
char dbuf[64];
char *ext_source = NULL;
format_time_interval(dbuf, sizeof(dbuf), apparent_skew);
if (conn)
tor_asprintf(&ext_source, "%s:%s:%d", source, conn->address, conn->port);
else
ext_source = tor_strdup(source);
log_fn(trusted ? LOG_WARN : LOG_INFO, domain,
"Received %s with skewed time (%s): "
"It seems that our clock is %s by %s, or that theirs is %s%s. "
"Tor requires an accurate clock to work: please check your time, "
"timezone, and date settings.", received, ext_source,
apparent_skew > 0 ? "ahead" : "behind", dbuf,
apparent_skew > 0 ? "behind" : "ahead",
(!conn || trusted) ? "" : ", or they are sending us the wrong time");
if (trusted)
control_event_general_status(LOG_WARN, "CLOCK_SKEW SKEW=%ld SOURCE=%s",
apparent_skew, ext_source);
tor_free(ext_source);
}