/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2017, 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:
*
* - listener_connection_t, implemented here in connection.c
*
- dir_connection_t, implemented in directory.c
*
- or_connection_t, implemented in connection_or.c
*
- edge_connection_t, implemented in connection_edge.c, along with
* its subtype(s):
*
- entry_connection_t, also implemented in connection_edge.c
*
* - control_connection_t, implemented in control.c
*
*
* 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_stop_writing().
*
* To queue data to be written on a connection, call
* connection_buf_add(). 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:
*
* - Listeners, which wait for incoming sockets and launch connections
*
- Outgoing SOCKS proxy support
*
- Outgoing HTTP proxy support
*
- An out-of-sockets handler for dealing with socket exhaustion
*
**/
#define CONNECTION_PRIVATE
#include "or.h"
#include "bridges.h"
#include "buffers.h"
#include "buffers_tls.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 "hs_common.h"
#include "hs_ident.h"
#include "nodelist.h"
#include "proto_http.h"
#include "proto_socks.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
#endif
#ifdef HAVE_SYS_UN_H
#include
#include
#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_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_buf_read_from_socket(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);
const tor_addr_t *conn_get_outbound_address(sa_family_t family,
const or_options_t *options, unsigned int conn_type);
/** 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: \
case CONN_TYPE_AP_HTTP_CONNECT_LISTENER
/**************************************************************/
/**
* Return the human-readable name for the connection type type
*/
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";
case CONN_TYPE_AP_HTTP_CONNECT_LISTENER: return "HTTP tunnel 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 state
* for the connection type type
*/
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 type
* to make or receive connections of address family socket_family. 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 type. 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 conn_a and conn_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 conn. Deallocate its buffers if
* necessary, close its socket if necessary, and mark the directory as dirty
* if conn is an OR or OP connection.
*/
STATIC void
connection_free_minimal(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);
hs_ident_edge_conn_free(TO_EDGE_CONN(conn)->hs_ident);
}
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_compress_free(dir_conn->compress_state);
if (dir_conn->spool) {
SMARTLIST_FOREACH(dir_conn->spool, spooled_resource_t *, spooled,
spooled_resource_free(spooled));
smartlist_free(dir_conn->spool);
}
rend_data_free(dir_conn->rend_data);
hs_ident_dir_conn_free(dir_conn->hs_ident);
if (dir_conn->guard_state) {
/* Cancel before freeing, if it's still there. */
entry_guard_cancel(&dir_conn->guard_state);
}
circuit_guard_state_free(dir_conn->guard_state);
}
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_clear_identity(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 conn 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_clear_identity(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 /* 1 */
/* 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_minimal(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 conn, 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 conn 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 conn 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.
* listenaddress provides the path to the Unix socket.
*
* Eventually listenaddress 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 readable_address will contain a copy of the path part of
* listenaddress.
*
* 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 /* !(defined(HAVE_SYS_UN_H) || defined(RUNNING_DOXYGEN)) */
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 /* defined(HAVE_SYS_UN_H) || defined(RUNNING_DOXYGEN) */
/** 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
* path. 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 /* defined(HAVE_SYS_UN_H) */
/** Tell the TCP stack that it shouldn't wait for a long time after
* sock 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 /* defined(_WIN32) */
}
#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 /* !(defined(SO_EXCLUSIVEADDRUSE)) */
(void) sock;
return 0;
#endif /* defined(SO_EXCLUSIVEADDRUSE) */
}
#endif /* defined(_WIN32) */
/** Max backlog to pass to listen. We start at */
static int listen_limit = INT_MAX;
/* Listen on fd 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 listensockaddr.
*
* address 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 /* defined(_WIN32) */
#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 /* defined(USE_TRANSPARENT) && defined(IP_TRANSPARENT) */
#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 /* defined(IPV6_V6ONLY) */
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 /* defined(HAVE_PWD_H) */
{
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 /* defined(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 got is the
* same as the one that listener 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 conn 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;
}
}
if (new_type == CONN_TYPE_OR) {
/* Assess with the connection DoS mitigation subsystem if this address
* can open a new connection. */
if (dos_conn_addr_get_defense_type(&addr) == DOS_CONN_DEFENSE_CLOSE) {
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 conn.
*
* 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.
*
* The listener parameter is only used for AP connections.
*/
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;
case CONN_TYPE_AP_HTTP_CONNECT_LISTENER:
conn->state = AP_CONN_STATE_HTTP_CONNECT_WAIT;
}
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 *socket_error.
* 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.
*
* We only check DisableNetwork here, not we_are_hibernating(), since
* we'll still try to fulfill client requests sometimes in the latter case
* (if it is soft hibernation) */
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 configured 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);
}
}
/** Retrieve the outbound address depending on the protocol (IPv4 or IPv6)
* and the connection type (relay, exit, ...)
* Return a socket address or NULL in case nothing is configured.
**/
const tor_addr_t *
conn_get_outbound_address(sa_family_t family,
const or_options_t *options, unsigned int conn_type)
{
const tor_addr_t *ext_addr = NULL;
int fam_index;
switch (family) {
case AF_INET:
fam_index = 0;
break;
case AF_INET6:
fam_index = 1;
break;
default:
return NULL;
}
// If an exit connection, use the exit address (if present)
if (conn_type == CONN_TYPE_EXIT) {
if (!tor_addr_is_null(
&options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT][fam_index])) {
ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT]
[fam_index];
} else if (!tor_addr_is_null(
&options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
[fam_index])) {
ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
[fam_index];
}
} else { // All non-exit connections
if (!tor_addr_is_null(
&options->OutboundBindAddresses[OUTBOUND_ADDR_OR][fam_index])) {
ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_OR]
[fam_index];
} else if (!tor_addr_is_null(
&options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
[fam_index])) {
ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
[fam_index];
}
}
return ext_addr;
}
/** 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 *socket_error.
* 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;
/* Log if we didn't stick to ClientUseIPv4/6 or ClientPreferIPv6OR/DirPort
*/
connection_connect_log_client_use_ip_version(conn);
if (!tor_addr_is_loopback(addr)) {
const tor_addr_t *ext_addr = NULL;
ext_addr = conn_get_outbound_address(tor_addr_family(addr), get_options(),
conn->type);
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 *socket_error. 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
* proxy_type 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 type (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_buf_add(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_buf_add((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_buf_add((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 conn, copying conn->addr
* and conn->port 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_buf_add((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_buf_add((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 old_conns, and list of
* port_cfg_t entries in ports, open a new listener for every port in
* ports that does not already have a listener in old_conns.
*
* Remove from old_conns every connection that has a corresponding
* entry in ports. Add to new_conns new every connection we
* launch.
*
* If control_listeners_only 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 /* !defined(_WIN32) */
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 replaced_conns.
* Add all new connections to new_conns.
*
* If close_all_noncontrol 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 conn, 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 conn 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 global_bucket
* we're willing to use for this transaction. base is the size
* of a cell on the network; priority says whether we should
* write many of them or just a few; and conn_bucket (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 attempt bytes of low-priority directory stuff
* out to conn. 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 num_read bytes and written
* num_written bytes on conn. */
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 tvnow 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 last_empty_time
* when a bucket ran empty that previously had tokens_before tokens
* now has tokens_after tokens after refilling at timestamp
* tvnow, capped at milliseconds_elapsed 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 tokens_before tokens and which got
* tokens_removed tokens removed at timestamp tvnow has run
* out of tokens, and if so, note the milliseconds since midnight in
* timestamp_var 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 num_read and wrote num_written bytes
* onto conn. 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));
tor_assert_nonfatal_unreached();
if (num_written >= INT_MAX)
num_written = 1;
if (num_read >= INT_MAX)
num_read = 1;
}
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 bucket called name with bandwidth rate per
* second rate and bandwidth burst burst, assuming that
* milliseconds_elapsed 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 bucket for connection conn 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_buf_read_from_socket() 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:
case CONN_TYPE_AP_HTTP_CONNECT_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_buf_read_from_socket(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 written 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_buf_read_from_socket(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 = buf_read_from_tls(conn->inbuf, or_conn->tls, at_most);
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 */
break;
case TOR_TLS_DONE: /* no data read, so nothing to process */
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 = buf_read_from_tls(conn->inbuf, or_conn->tls, pending);
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 = buf_move_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 = buf_read_from_socket(conn->inbuf, conn->s,
at_most,
&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_buf_get_bytes(char *string, size_t len, connection_t *conn)
{
return buf_get_bytes(conn->inbuf, string, len);
}
/** As buf_get_line(), but read from a connection's input buffer. */
int
connection_buf_get_line(connection_t *conn, char *data,
size_t *data_len)
{
return buf_get_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 conn'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);
}
/**
* On Windows Vista and Windows 7, tune the send buffer size according to a
* hint from the OS.
*
* This should help fix slow upload rates.
*/
static void
update_send_buffer_size(tor_socket_t sock)
{
#ifdef _WIN32
/* We only do this on Vista and 7, because earlier versions of Windows
* don't have the SIO_IDEAL_SEND_BACKLOG_QUERY functionality, and on
* later versions it isn't necessary. */
static int isVistaOr7 = -1;
if (isVistaOr7 == -1) {
isVistaOr7 = 0;
OSVERSIONINFO osvi = { 0 };
osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
GetVersionEx(&osvi);
if (osvi.dwMajorVersion == 6 && osvi.dwMinorVersion < 2)
isVistaOr7 = 1;
}
if (!isVistaOr7)
return;
if (get_options()->ConstrainedSockets)
return;
ULONG isb = 0;
DWORD bytesReturned = 0;
if (!WSAIoctl(sock, SIO_IDEAL_SEND_BACKLOG_QUERY, NULL, 0,
&isb, sizeof(isb), &bytesReturned, NULL, NULL)) {
setsockopt(sock, SOL_SOCKET, SO_SNDBUF, (const char*)&isb, sizeof(isb));
}
#else
(void) sock;
#endif
}
/** Try to flush more bytes onto conn-\>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_buf_add() when an entire TLS record is ready.
*
* Update conn-\>timestamp_lastwritten to now, and call flush_buf
* or flush_buf_tls appropriately. If it succeeds and there are no more
* more bytes on conn-\>outbuf, then call connection_finished_flushing
* on it too.
*
* If force, 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 = buf_flush_to_tls(conn->outbuf, or_conn->tls,
max_to_write, &conn->outbuf_flushlen);
if (result >= 0)
update_send_buffer_size(conn->s);
/* 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 = buf_flush_to_socket(conn->outbuf, conn->s,
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;
}
update_send_buffer_size(conn->s);
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 conn. 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);
}
/** Helper for connection_write_to_buf_impl and connection_write_buf_to_buf:
*
* Return true iff it is okay to queue bytes on conn's outbuf for
* writing.
*/
static int
connection_may_write_to_buf(connection_t *conn)
{
/* 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 0;
return 1;
}
/** Helper for connection_write_to_buf_impl and connection_write_buf_to_buf:
*
* Called when an attempt to add bytes on conn's outbuf has failed;
* mark the connection and warn as appropriate.
*/
static void
connection_write_to_buf_failed(connection_t *conn)
{
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);
}
}
/** Helper for connection_write_to_buf_impl and connection_write_buf_to_buf:
*
* Called when an attempt to add bytes on conn's outbuf has succeeded:
* record the number of bytes added.
*/
static void
connection_write_to_buf_commit(connection_t *conn, size_t len)
{
/* 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);
}
conn->outbuf_flushlen += len;
}
/** Append len bytes of string onto conn's
* outbuf, and ask it to start writing.
*
* If zlib 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.
*/
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;
if (!len && !(zlib<0))
return;
if (!connection_may_write_to_buf(conn))
return;
size_t written;
if (zlib) {
size_t old_datalen = buf_datalen(conn->outbuf);
dir_connection_t *dir_conn = TO_DIR_CONN(conn);
int done = zlib < 0;
CONN_LOG_PROTECT(conn, r = buf_add_compress(conn->outbuf,
dir_conn->compress_state,
string, len, done));
written = buf_datalen(conn->outbuf) - old_datalen;
} else {
CONN_LOG_PROTECT(conn, r = buf_add(conn->outbuf, string, len));
written = len;
}
if (r < 0) {
connection_write_to_buf_failed(conn);
return;
}
connection_write_to_buf_commit(conn, written);
}
/**
* Add all bytes from buf to conn's outbuf, draining them
* from buf. (If the connection is marked and will soon be closed,
* nothing is drained.)
*/
void
connection_buf_add_buf(connection_t *conn, buf_t *buf)
{
tor_assert(conn);
tor_assert(buf);
size_t len = buf_datalen(buf);
if (len == 0)
return;
if (!connection_may_write_to_buf(conn))
return;
buf_move_all(conn->outbuf, buf);
connection_write_to_buf_commit(conn, len);
}
#define CONN_GET_ALL_TEMPLATE(var, test) \
STMT_BEGIN \
smartlist_t *conns = get_connection_array(); \
smartlist_t *ret_conns = smartlist_new(); \
SMARTLIST_FOREACH_BEGIN(conns, connection_t *, var) { \
if (var && (test) && !var->marked_for_close) \
smartlist_add(ret_conns, var); \
} SMARTLIST_FOREACH_END(var); \
return ret_conns; \
STMT_END
/* Return a list of connections that aren't close and matches the given type
* and state. The returned list can be empty and must be freed using
* smartlist_free(). The caller does NOT have ownership of the objects in the
* list so it must not free them nor reference them as they can disappear. */
smartlist_t *
connection_list_by_type_state(int type, int state)
{
CONN_GET_ALL_TEMPLATE(conn, (conn->type == type && conn->state == state));
}
/* Return a list of connections that aren't close and matches the given type
* and purpose. The returned list can be empty and must be freed using
* smartlist_free(). The caller does NOT have ownership of the objects in the
* list so it must not free them nor reference them as they can disappear. */
smartlist_t *
connection_list_by_type_purpose(int type, int purpose)
{
CONN_GET_ALL_TEMPLATE(conn,
(conn->type == type && conn->purpose == purpose));
}
/** 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 id 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 type 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 type that is in state state,
* 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 type that has rendquery equal
* to rendquery, 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,
rend_data_get_address(TO_DIR_CONN(conn)->rend_data)))
||
(CONN_IS_EDGE(conn) &&
TO_EDGE_CONN(conn)->rend_data &&
!rend_cmp_service_ids(rendquery,
rend_data_get_address(TO_EDGE_CONN(conn)->rend_data)))
));
}
/** 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 purpose/resource. 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 purpose/resource/state. 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 this_conn.
*
* 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
* this_conn.
*
* 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 conn 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_AP_HTTP_CONNECT_LISTENER ||
conn->type == CONN_TYPE_DIR_LISTENER ||
conn->type == CONN_TYPE_CONTROL_LISTENER)
return 1;
return 0;
}
/** Return 1 if conn 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 authenticator. 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 conn 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)
buf_assert_ok(conn->inbuf);
if (conn->outbuf)
buf_assert_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 addr and port with the details of the global
* proxy server we are using.
* conn 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.
* conn 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 proxy_type. */
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_minimal() 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_minimal(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 received came
* at a skewed time. trusted indicates that the source 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, *warn = 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_asprintf(&warn, "Clock skew %ld in %s from %s", apparent_skew,
received, source);
control_event_bootstrap_problem(warn, "CLOCK_SKEW", conn, 1);
}
tor_free(warn);
tor_free(ext_source);
}