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[tor-commits] [tor/maint-0.4.1] Merge branch 'bug31466_029' into bug31466_035_tmp
commit bf4a27c0eae79baff7f0ed4ebe12bda5e2ba06b6
Merge: 02840169d f0e412099
Author: Nick Mathewson <nickm@xxxxxxxxxxxxxx>
Date: Wed Sep 18 15:42:40 2019 -0400
Merge branch 'bug31466_029' into bug31466_035_tmp
changes/ticket31466 | 5 +++++
src/core/or/connection_edge.c | 6 ++++--
2 files changed, 9 insertions(+), 2 deletions(-)
diff --cc src/core/or/connection_edge.c
index 7cc67d7f5,000000000..90991107d
mode 100644,000000..100644
--- a/src/core/or/connection_edge.c
+++ b/src/core/or/connection_edge.c
@@@ -1,4537 -1,0 +1,4539 @@@
+/* Copyright (c) 2001 Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file connection_edge.c
+ * \brief Handle edge streams.
+ *
+ * An edge_connection_t is a subtype of a connection_t, and represents two
+ * critical concepts in Tor: a stream, and an edge connection. From the Tor
+ * protocol's point of view, a stream is a bi-directional channel that is
+ * multiplexed on a single circuit. Each stream on a circuit is identified
+ * with a separate 16-bit stream ID, local to the (circuit,exit) pair.
+ * Streams are created in response to client requests.
+ *
+ * An edge connection is one thing that can implement a stream: it is either a
+ * TCP application socket that has arrived via (e.g.) a SOCKS request, or an
+ * exit connection.
+ *
+ * Not every instance of edge_connection_t truly represents an edge connction,
+ * however. (Sorry!) We also create edge_connection_t objects for streams that
+ * we will not be handling with TCP. The types of these streams are:
+ * <ul>
+ * <li>DNS lookup streams, created on the client side in response to
+ * a UDP DNS request received on a DNSPort, or a RESOLVE command
+ * on a controller.
+ * <li>DNS lookup streams, created on the exit side in response to
+ * a RELAY_RESOLVE cell from a client.
+ * <li>Tunneled directory streams, created on the directory cache side
+ * in response to a RELAY_BEGIN_DIR cell. These streams attach directly
+ * to a dir_connection_t object without ever using TCP.
+ * </ul>
+ *
+ * This module handles general-purpose functionality having to do with
+ * edge_connection_t. On the client side, it accepts various types of
+ * application requests on SocksPorts, TransPorts, and NATDPorts, and
+ * creates streams appropriately.
+ *
+ * This module is also responsible for implementing stream isolation:
+ * ensuring that streams that should not be linkable to one another are
+ * kept to different circuits.
+ *
+ * On the exit side, this module handles the various stream-creating
+ * type of RELAY cells by launching appropriate outgoing connections,
+ * DNS requests, or directory connection objects.
+ *
+ * And for all edge connections, this module is responsible for handling
+ * incoming and outdoing data as it arrives or leaves in the relay.c
+ * module. (Outgoing data will be packaged in
+ * connection_edge_process_inbuf() as it calls
+ * connection_edge_package_raw_inbuf(); incoming data from RELAY_DATA
+ * cells is applied in connection_edge_process_relay_cell().)
+ **/
+#define CONNECTION_EDGE_PRIVATE
+
+#include "core/or/or.h"
+
+#include "lib/err/backtrace.h"
+
+#include "app/config/config.h"
+#include "core/mainloop/connection.h"
+#include "core/mainloop/mainloop.h"
+#include "core/or/channel.h"
+#include "core/or/circuitbuild.h"
+#include "core/or/circuitlist.h"
+#include "core/or/circuituse.h"
+#include "core/or/connection_edge.h"
+#include "core/or/connection_or.h"
+#include "core/or/policies.h"
+#include "core/or/reasons.h"
+#include "core/or/relay.h"
+#include "core/proto/proto_http.h"
+#include "core/proto/proto_socks.h"
+#include "feature/client/addressmap.h"
+#include "feature/client/circpathbias.h"
+#include "feature/client/dnsserv.h"
+#include "feature/control/control.h"
+#include "feature/dircache/dirserv.h"
+#include "feature/dircommon/directory.h"
+#include "feature/hibernate/hibernate.h"
+#include "feature/hs/hs_cache.h"
+#include "feature/hs/hs_circuit.h"
+#include "feature/hs/hs_client.h"
+#include "feature/hs/hs_common.h"
+#include "feature/nodelist/describe.h"
+#include "feature/nodelist/networkstatus.h"
+#include "feature/nodelist/nodelist.h"
+#include "feature/nodelist/routerlist.h"
+#include "feature/nodelist/routerset.h"
+#include "feature/relay/dns.h"
+#include "feature/relay/router.h"
+#include "feature/relay/routermode.h"
+#include "feature/rend/rendclient.h"
+#include "feature/rend/rendcommon.h"
+#include "feature/rend/rendservice.h"
+#include "feature/stats/predict_ports.h"
+#include "feature/stats/rephist.h"
+#include "lib/container/buffers.h"
+#include "lib/crypt_ops/crypto_util.h"
+
+#include "core/or/cell_st.h"
+#include "core/or/cpath_build_state_st.h"
+#include "feature/dircommon/dir_connection_st.h"
+#include "core/or/entry_connection_st.h"
+#include "core/or/extend_info_st.h"
+#include "feature/nodelist/node_st.h"
+#include "core/or/or_circuit_st.h"
+#include "core/or/origin_circuit_st.h"
+#include "core/or/half_edge_st.h"
+#include "core/or/socks_request_st.h"
+#include "lib/evloop/compat_libevent.h"
+
+#ifdef HAVE_LINUX_TYPES_H
+#include <linux/types.h>
+#endif
+#ifdef HAVE_LINUX_NETFILTER_IPV4_H
+#include <linux/netfilter_ipv4.h>
+#define TRANS_NETFILTER
+#define TRANS_NETFILTER_IPV4
+#endif
+
+#ifdef HAVE_LINUX_IF_H
+#include <linux/if.h>
+#endif
+
+#ifdef HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H
+#include <linux/netfilter_ipv6/ip6_tables.h>
+#if defined(IP6T_SO_ORIGINAL_DST)
+#define TRANS_NETFILTER
+#define TRANS_NETFILTER_IPV6
+#endif
+#endif /* defined(HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H) */
+
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#ifdef HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+
+#if defined(HAVE_NET_IF_H) && defined(HAVE_NET_PFVAR_H)
+#include <net/if.h>
+#include <net/pfvar.h>
+#define TRANS_PF
+#endif
+
+#ifdef IP_TRANSPARENT
+#define TRANS_TPROXY
+#endif
+
+#define SOCKS4_GRANTED 90
+#define SOCKS4_REJECT 91
+
+static int connection_ap_handshake_process_socks(entry_connection_t *conn);
+static int connection_ap_process_natd(entry_connection_t *conn);
+static int connection_exit_connect_dir(edge_connection_t *exitconn);
+static int consider_plaintext_ports(entry_connection_t *conn, uint16_t port);
+static int connection_ap_supports_optimistic_data(const entry_connection_t *);
+
+/** Convert a connection_t* to an edge_connection_t*; assert if the cast is
+ * invalid. */
+edge_connection_t *
+TO_EDGE_CONN(connection_t *c)
+{
+ tor_assert(c->magic == EDGE_CONNECTION_MAGIC ||
+ c->magic == ENTRY_CONNECTION_MAGIC);
+ return DOWNCAST(edge_connection_t, c);
+}
+
+entry_connection_t *
+TO_ENTRY_CONN(connection_t *c)
+{
+ tor_assert(c->magic == ENTRY_CONNECTION_MAGIC);
+ return (entry_connection_t*) SUBTYPE_P(c, entry_connection_t, edge_.base_);
+}
+
+entry_connection_t *
+EDGE_TO_ENTRY_CONN(edge_connection_t *c)
+{
+ tor_assert(c->base_.magic == ENTRY_CONNECTION_MAGIC);
+ return (entry_connection_t*) SUBTYPE_P(c, entry_connection_t, edge_);
+}
+
+/** An AP stream has failed/finished. If it hasn't already sent back
+ * a socks reply, send one now (based on endreason). Also set
+ * has_sent_end to 1, and mark the conn.
+ */
+MOCK_IMPL(void,
+connection_mark_unattached_ap_,(entry_connection_t *conn, int endreason,
+ int line, const char *file))
+{
+ connection_t *base_conn = ENTRY_TO_CONN(conn);
+ edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(conn);
+ tor_assert(base_conn->type == CONN_TYPE_AP);
+ ENTRY_TO_EDGE_CONN(conn)->edge_has_sent_end = 1; /* no circ yet */
+
+ /* If this is a rendezvous stream and it is failing without ever
+ * being attached to a circuit, assume that an attempt to connect to
+ * the destination hidden service has just ended.
+ *
+ * XXXX This condition doesn't limit to only streams failing
+ * without ever being attached. That sloppiness should be harmless,
+ * but we should fix it someday anyway. */
+ if ((edge_conn->on_circuit != NULL || edge_conn->edge_has_sent_end) &&
+ connection_edge_is_rendezvous_stream(edge_conn)) {
+ if (edge_conn->rend_data) {
+ rend_client_note_connection_attempt_ended(edge_conn->rend_data);
+ }
+ }
+
+ if (base_conn->marked_for_close) {
+ /* This call will warn as appropriate. */
+ connection_mark_for_close_(base_conn, line, file);
+ return;
+ }
+
+ if (!conn->socks_request->has_finished) {
+ if (endreason & END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED)
+ log_warn(LD_BUG,
+ "stream (marked at %s:%d) sending two socks replies?",
+ file, line);
+
+ if (SOCKS_COMMAND_IS_CONNECT(conn->socks_request->command))
+ connection_ap_handshake_socks_reply(conn, NULL, 0, endreason);
+ else if (SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command))
+ connection_ap_handshake_socks_resolved(conn,
+ RESOLVED_TYPE_ERROR_TRANSIENT,
+ 0, NULL, -1, -1);
+ else /* unknown or no handshake at all. send no response. */
+ conn->socks_request->has_finished = 1;
+ }
+
+ connection_mark_and_flush_(base_conn, line, file);
+
+ ENTRY_TO_EDGE_CONN(conn)->end_reason = endreason;
+}
+
+/** There was an EOF. Send an end and mark the connection for close.
+ */
+int
+connection_edge_reached_eof(edge_connection_t *conn)
+{
+ if (connection_get_inbuf_len(TO_CONN(conn)) &&
+ connection_state_is_open(TO_CONN(conn))) {
+ /* it still has stuff to process. don't let it die yet. */
+ return 0;
+ }
+ log_info(LD_EDGE,"conn (fd "TOR_SOCKET_T_FORMAT") reached eof. Closing.",
+ conn->base_.s);
+ if (!conn->base_.marked_for_close) {
+ /* only mark it if not already marked. it's possible to
+ * get the 'end' right around when the client hangs up on us. */
+ connection_edge_end(conn, END_STREAM_REASON_DONE);
+ if (conn->base_.type == CONN_TYPE_AP) {
+ /* eof, so don't send a socks reply back */
+ if (EDGE_TO_ENTRY_CONN(conn)->socks_request)
+ EDGE_TO_ENTRY_CONN(conn)->socks_request->has_finished = 1;
+ }
+ connection_mark_for_close(TO_CONN(conn));
+ }
+ return 0;
+}
+
+/** Handle new bytes on conn->inbuf based on state:
+ * - If it's waiting for socks info, try to read another step of the
+ * socks handshake out of conn->inbuf.
+ * - If it's waiting for the original destination, fetch it.
+ * - If it's open, then package more relay cells from the stream.
+ * - Else, leave the bytes on inbuf alone for now.
+ *
+ * Mark and return -1 if there was an unexpected error with the conn,
+ * else return 0.
+ */
+int
+connection_edge_process_inbuf(edge_connection_t *conn, int package_partial)
+{
+ tor_assert(conn);
+
+ switch (conn->base_.state) {
+ case AP_CONN_STATE_SOCKS_WAIT:
+ if (connection_ap_handshake_process_socks(EDGE_TO_ENTRY_CONN(conn)) <0) {
+ /* already marked */
+ return -1;
+ }
+ return 0;
+ case AP_CONN_STATE_NATD_WAIT:
+ if (connection_ap_process_natd(EDGE_TO_ENTRY_CONN(conn)) < 0) {
+ /* already marked */
+ return -1;
+ }
+ return 0;
+ case AP_CONN_STATE_HTTP_CONNECT_WAIT:
+ if (connection_ap_process_http_connect(EDGE_TO_ENTRY_CONN(conn)) < 0) {
+ return -1;
+ }
+ return 0;
+ case AP_CONN_STATE_OPEN:
+ case EXIT_CONN_STATE_OPEN:
+ if (connection_edge_package_raw_inbuf(conn, package_partial, NULL) < 0) {
+ /* (We already sent an end cell if possible) */
+ connection_mark_for_close(TO_CONN(conn));
+ return -1;
+ }
+ return 0;
+ case AP_CONN_STATE_CONNECT_WAIT:
+ if (connection_ap_supports_optimistic_data(EDGE_TO_ENTRY_CONN(conn))) {
+ log_info(LD_EDGE,
+ "data from edge while in '%s' state. Sending it anyway. "
+ "package_partial=%d, buflen=%ld",
+ conn_state_to_string(conn->base_.type, conn->base_.state),
+ package_partial,
+ (long)connection_get_inbuf_len(TO_CONN(conn)));
+ if (connection_edge_package_raw_inbuf(conn, package_partial, NULL)<0) {
+ /* (We already sent an end cell if possible) */
+ connection_mark_for_close(TO_CONN(conn));
+ return -1;
+ }
+ return 0;
+ }
+ /* Fall through if the connection is on a circuit without optimistic
+ * data support. */
+ /* Falls through. */
+ case EXIT_CONN_STATE_CONNECTING:
+ case AP_CONN_STATE_RENDDESC_WAIT:
+ case AP_CONN_STATE_CIRCUIT_WAIT:
+ case AP_CONN_STATE_RESOLVE_WAIT:
+ case AP_CONN_STATE_CONTROLLER_WAIT:
+ log_info(LD_EDGE,
+ "data from edge while in '%s' state. Leaving it on buffer.",
+ conn_state_to_string(conn->base_.type, conn->base_.state));
+ return 0;
+ }
+ log_warn(LD_BUG,"Got unexpected state %d. Closing.",conn->base_.state);
+ tor_fragile_assert();
+ connection_edge_end(conn, END_STREAM_REASON_INTERNAL);
+ connection_mark_for_close(TO_CONN(conn));
+ return -1;
+}
+
+/** This edge needs to be closed, because its circuit has closed.
+ * Mark it for close and return 0.
+ */
+int
+connection_edge_destroy(circid_t circ_id, edge_connection_t *conn)
+{
+ if (!conn->base_.marked_for_close) {
+ log_info(LD_EDGE, "CircID %u: At an edge. Marking connection for close.",
+ (unsigned) circ_id);
+ if (conn->base_.type == CONN_TYPE_AP) {
+ entry_connection_t *entry_conn = EDGE_TO_ENTRY_CONN(conn);
+ connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_DESTROY);
+ control_event_stream_bandwidth(conn);
+ control_event_stream_status(entry_conn, STREAM_EVENT_CLOSED,
+ END_STREAM_REASON_DESTROY);
+ conn->end_reason |= END_STREAM_REASON_FLAG_ALREADY_SENT_CLOSED;
+ } else {
+ /* closing the circuit, nothing to send an END to */
+ conn->edge_has_sent_end = 1;
+ conn->end_reason = END_STREAM_REASON_DESTROY;
+ conn->end_reason |= END_STREAM_REASON_FLAG_ALREADY_SENT_CLOSED;
+ connection_mark_and_flush(TO_CONN(conn));
+ }
+ }
+ conn->cpath_layer = NULL;
+ conn->on_circuit = NULL;
+ return 0;
+}
+
+/** Send a raw end cell to the stream with ID <b>stream_id</b> out over the
+ * <b>circ</b> towards the hop identified with <b>cpath_layer</b>. If this
+ * is not a client connection, set the relay end cell's reason for closing
+ * as <b>reason</b> */
+static int
+relay_send_end_cell_from_edge(streamid_t stream_id, circuit_t *circ,
+ uint8_t reason, crypt_path_t *cpath_layer)
+{
+ char payload[1];
+
+ if (CIRCUIT_PURPOSE_IS_CLIENT(circ->purpose)) {
+ /* Never send the server an informative reason code; it doesn't need to
+ * know why the client stream is failing. */
+ reason = END_STREAM_REASON_MISC;
+ }
+
+ payload[0] = (char) reason;
+
+ /* Note: we have to use relay_send_command_from_edge here, not
+ * connection_edge_end or connection_edge_send_command, since those require
+ * that we have a stream connected to a circuit, and we don't connect to a
+ * circuit until we have a pending/successful resolve. */
+ return relay_send_command_from_edge(stream_id, circ, RELAY_COMMAND_END,
+ payload, 1, cpath_layer);
+}
+
+/* If the connection <b>conn</b> is attempting to connect to an external
+ * destination that is an hidden service and the reason is a connection
+ * refused or timeout, log it so the operator can take appropriate actions.
+ * The log statement is a rate limited warning. */
+static void
+warn_if_hs_unreachable(const edge_connection_t *conn, uint8_t reason)
+{
+ tor_assert(conn);
+
+ if (conn->base_.type == CONN_TYPE_EXIT &&
+ connection_edge_is_rendezvous_stream(conn) &&
+ (reason == END_STREAM_REASON_CONNECTREFUSED ||
+ reason == END_STREAM_REASON_TIMEOUT)) {
+#define WARN_FAILED_HS_CONNECTION 300
+ static ratelim_t warn_limit = RATELIM_INIT(WARN_FAILED_HS_CONNECTION);
+ char *m;
+ if ((m = rate_limit_log(&warn_limit, approx_time()))) {
+ log_warn(LD_EDGE, "Onion service connection to %s failed (%s)",
+ (conn->base_.socket_family == AF_UNIX) ?
+ safe_str(conn->base_.address) :
+ safe_str(fmt_addrport(&conn->base_.addr, conn->base_.port)),
+ stream_end_reason_to_string(reason));
+ tor_free(m);
+ }
+ }
+}
+
+/** Send a relay end cell from stream <b>conn</b> down conn's circuit, and
+ * remember that we've done so. If this is not a client connection, set the
+ * relay end cell's reason for closing as <b>reason</b>.
+ *
+ * Return -1 if this function has already been called on this conn,
+ * else return 0.
+ */
+int
+connection_edge_end(edge_connection_t *conn, uint8_t reason)
+{
+ char payload[RELAY_PAYLOAD_SIZE];
+ size_t payload_len=1;
+ circuit_t *circ;
+ uint8_t control_reason = reason;
+
+ if (conn->edge_has_sent_end) {
+ log_warn(LD_BUG,"(Harmless.) Calling connection_edge_end (reason %d) "
+ "on an already ended stream?", reason);
+ tor_fragile_assert();
+ return -1;
+ }
+
+ if (conn->base_.marked_for_close) {
+ log_warn(LD_BUG,
+ "called on conn that's already marked for close at %s:%d.",
+ conn->base_.marked_for_close_file, conn->base_.marked_for_close);
+ return 0;
+ }
+
+ circ = circuit_get_by_edge_conn(conn);
+ if (circ && CIRCUIT_PURPOSE_IS_CLIENT(circ->purpose)) {
+ /* If this is a client circuit, don't send the server an informative
+ * reason code; it doesn't need to know why the client stream is
+ * failing. */
+ reason = END_STREAM_REASON_MISC;
+ }
+
+ payload[0] = (char)reason;
+ if (reason == END_STREAM_REASON_EXITPOLICY &&
+ !connection_edge_is_rendezvous_stream(conn)) {
+ int addrlen;
+ if (tor_addr_family(&conn->base_.addr) == AF_INET) {
+ set_uint32(payload+1, tor_addr_to_ipv4n(&conn->base_.addr));
+ addrlen = 4;
+ } else {
+ memcpy(payload+1, tor_addr_to_in6_addr8(&conn->base_.addr), 16);
+ addrlen = 16;
+ }
+ set_uint32(payload+1+addrlen, htonl(dns_clip_ttl(conn->address_ttl)));
+ payload_len += 4+addrlen;
+ }
+
+ if (circ && !circ->marked_for_close) {
+ log_debug(LD_EDGE,"Sending end on conn (fd "TOR_SOCKET_T_FORMAT").",
+ conn->base_.s);
+
+ if (CIRCUIT_IS_ORIGIN(circ)) {
+ origin_circuit_t *origin_circ = TO_ORIGIN_CIRCUIT(circ);
+ connection_half_edge_add(conn, origin_circ);
+ }
+
+ connection_edge_send_command(conn, RELAY_COMMAND_END,
+ payload, payload_len);
+ /* We'll log warn if the connection was an hidden service and couldn't be
+ * made because the service wasn't available. */
+ warn_if_hs_unreachable(conn, control_reason);
+ } else {
+ log_debug(LD_EDGE,"No circ to send end on conn "
+ "(fd "TOR_SOCKET_T_FORMAT").",
+ conn->base_.s);
+ }
+
+ conn->edge_has_sent_end = 1;
+ conn->end_reason = control_reason;
+ return 0;
+}
+
+/**
+ * Helper function for bsearch.
+ *
+ * As per smartlist_bsearch, return < 0 if key preceeds member,
+ * > 0 if member preceeds key, and 0 if they are equal.
+ *
+ * This is equivalent to subtraction of the values of key - member
+ * (why does no one ever say that explicitly?).
+ */
+static int
+connection_half_edge_compare_bsearch(const void *key, const void **member)
+{
+ const half_edge_t *e2;
+ tor_assert(key);
+ tor_assert(member && *(half_edge_t**)member);
+ e2 = *(const half_edge_t **)member;
+
+ return *(const streamid_t*)key - e2->stream_id;
+}
+
+/** Total number of half_edge_t objects allocated */
+static size_t n_half_conns_allocated = 0;
+
+/**
+ * Add a half-closed connection to the list, to watch for activity.
+ *
+ * These connections are removed from the list upon receiving an end
+ * cell.
+ */
+STATIC void
+connection_half_edge_add(const edge_connection_t *conn,
+ origin_circuit_t *circ)
+{
+ half_edge_t *half_conn = NULL;
+ int insert_at = 0;
+ int ignored;
+
+ /* Double-check for re-insertion. This should not happen,
+ * but this check is cheap compared to the sort anyway */
+ if (connection_half_edge_find_stream_id(circ->half_streams,
+ conn->stream_id)) {
+ log_warn(LD_BUG, "Duplicate stream close for stream %d on circuit %d",
+ conn->stream_id, circ->global_identifier);
+ return;
+ }
+
+ half_conn = tor_malloc_zero(sizeof(half_edge_t));
+ ++n_half_conns_allocated;
+
+ if (!circ->half_streams) {
+ circ->half_streams = smartlist_new();
+ }
+
+ half_conn->stream_id = conn->stream_id;
+
+ // How many sendme's should I expect?
+ half_conn->sendmes_pending =
+ (STREAMWINDOW_START-conn->package_window)/STREAMWINDOW_INCREMENT;
+
+ // Is there a connected cell pending?
+ half_conn->connected_pending = conn->base_.state ==
+ AP_CONN_STATE_CONNECT_WAIT;
+
+ /* Data should only arrive if we're not waiting on a resolved cell.
+ * It can arrive after waiting on connected, because of optimistic
+ * data. */
+ if (conn->base_.state != AP_CONN_STATE_RESOLVE_WAIT) {
+ // How many more data cells can arrive on this id?
+ half_conn->data_pending = conn->deliver_window;
+ }
+
+ insert_at = smartlist_bsearch_idx(circ->half_streams, &half_conn->stream_id,
+ connection_half_edge_compare_bsearch,
+ &ignored);
+ smartlist_insert(circ->half_streams, insert_at, half_conn);
+}
+
+/** Release space held by <b>he</b> */
+void
+half_edge_free_(half_edge_t *he)
+{
+ if (!he)
+ return;
+ --n_half_conns_allocated;
+ tor_free(he);
+}
+
+/** Return the number of bytes devoted to storing info on half-open streams. */
+size_t
+half_streams_get_total_allocation(void)
+{
+ return n_half_conns_allocated * sizeof(half_edge_t);
+}
+
+/**
+ * Find a stream_id_t in the list in O(lg(n)).
+ *
+ * Returns NULL if the list is empty or element is not found.
+ * Returns a pointer to the element if found.
+ */
+STATIC half_edge_t *
+connection_half_edge_find_stream_id(const smartlist_t *half_conns,
+ streamid_t stream_id)
+{
+ if (!half_conns)
+ return NULL;
+
+ return smartlist_bsearch(half_conns, &stream_id,
+ connection_half_edge_compare_bsearch);
+}
+
+/**
+ * Check if this stream_id is in a half-closed state. If so,
+ * check if it still has data cells pending, and decrement that
+ * window if so.
+ *
+ * Return 1 if the data window was not empty.
+ * Return 0 otherwise.
+ */
+int
+connection_half_edge_is_valid_data(const smartlist_t *half_conns,
+ streamid_t stream_id)
+{
+ half_edge_t *half = connection_half_edge_find_stream_id(half_conns,
+ stream_id);
+
+ if (!half)
+ return 0;
+
+ if (half->data_pending > 0) {
+ half->data_pending--;
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * Check if this stream_id is in a half-closed state. If so,
+ * check if it still has a connected cell pending, and decrement
+ * that window if so.
+ *
+ * Return 1 if the connected window was not empty.
+ * Return 0 otherwise.
+ */
+int
+connection_half_edge_is_valid_connected(const smartlist_t *half_conns,
+ streamid_t stream_id)
+{
+ half_edge_t *half = connection_half_edge_find_stream_id(half_conns,
+ stream_id);
+
+ if (!half)
+ return 0;
+
+ if (half->connected_pending) {
+ half->connected_pending = 0;
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * Check if this stream_id is in a half-closed state. If so,
+ * check if it still has sendme cells pending, and decrement that
+ * window if so.
+ *
+ * Return 1 if the sendme window was not empty.
+ * Return 0 otherwise.
+ */
+int
+connection_half_edge_is_valid_sendme(const smartlist_t *half_conns,
+ streamid_t stream_id)
+{
+ half_edge_t *half = connection_half_edge_find_stream_id(half_conns,
+ stream_id);
+
+ if (!half)
+ return 0;
+
+ if (half->sendmes_pending > 0) {
+ half->sendmes_pending--;
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * Check if this stream_id is in a half-closed state. If so, remove
+ * it from the list. No other data should come after the END cell.
+ *
+ * Return 1 if stream_id was in half-closed state.
+ * Return 0 otherwise.
+ */
+int
+connection_half_edge_is_valid_end(smartlist_t *half_conns,
+ streamid_t stream_id)
+{
+ half_edge_t *half;
+ int found, remove_idx;
+
+ if (!half_conns)
+ return 0;
+
+ remove_idx = smartlist_bsearch_idx(half_conns, &stream_id,
+ connection_half_edge_compare_bsearch,
+ &found);
+ if (!found)
+ return 0;
+
+ half = smartlist_get(half_conns, remove_idx);
+ smartlist_del_keeporder(half_conns, remove_idx);
+ half_edge_free(half);
+ return 1;
+}
+
+/**
+ * Streams that were used to send a RESOLVE cell are closed
+ * when they get the RESOLVED, without an end. So treat
+ * a RESOLVED just like an end, and remove from the list.
+ */
+int
+connection_half_edge_is_valid_resolved(smartlist_t *half_conns,
+ streamid_t stream_id)
+{
+ return connection_half_edge_is_valid_end(half_conns, stream_id);
+}
+
+/** An error has just occurred on an operation on an edge connection
+ * <b>conn</b>. Extract the errno; convert it to an end reason, and send an
+ * appropriate relay end cell to the other end of the connection's circuit.
+ **/
+int
+connection_edge_end_errno(edge_connection_t *conn)
+{
+ uint8_t reason;
+ tor_assert(conn);
+ reason = errno_to_stream_end_reason(tor_socket_errno(conn->base_.s));
+ return connection_edge_end(conn, reason);
+}
+
+/** We just wrote some data to <b>conn</b>; act appropriately.
+ *
+ * (That is, if it's open, consider sending a stream-level sendme cell if we
+ * have just flushed enough.)
+ */
+int
+connection_edge_flushed_some(edge_connection_t *conn)
+{
+ switch (conn->base_.state) {
+ case AP_CONN_STATE_OPEN:
+ case EXIT_CONN_STATE_OPEN:
+ connection_edge_consider_sending_sendme(conn);
+ break;
+ }
+ return 0;
+}
+
+/** Connection <b>conn</b> has finished writing and has no bytes left on
+ * its outbuf.
+ *
+ * If it's in state 'open', stop writing, consider responding with a
+ * sendme, and return.
+ * Otherwise, stop writing and return.
+ *
+ * If <b>conn</b> is broken, mark it for close and return -1, else
+ * return 0.
+ */
+int
+connection_edge_finished_flushing(edge_connection_t *conn)
+{
+ tor_assert(conn);
+
+ switch (conn->base_.state) {
+ case AP_CONN_STATE_OPEN:
+ case EXIT_CONN_STATE_OPEN:
+ connection_edge_consider_sending_sendme(conn);
+ return 0;
+ case AP_CONN_STATE_SOCKS_WAIT:
+ case AP_CONN_STATE_NATD_WAIT:
+ case AP_CONN_STATE_RENDDESC_WAIT:
+ case AP_CONN_STATE_CIRCUIT_WAIT:
+ case AP_CONN_STATE_CONNECT_WAIT:
+ case AP_CONN_STATE_CONTROLLER_WAIT:
+ case AP_CONN_STATE_RESOLVE_WAIT:
+ case AP_CONN_STATE_HTTP_CONNECT_WAIT:
+ return 0;
+ default:
+ log_warn(LD_BUG, "Called in unexpected state %d.",conn->base_.state);
+ tor_fragile_assert();
+ return -1;
+ }
+ return 0;
+}
+
+/** Longest size for the relay payload of a RELAY_CONNECTED cell that we're
+ * able to generate. */
+/* 4 zero bytes; 1 type byte; 16 byte IPv6 address; 4 byte TTL. */
+#define MAX_CONNECTED_CELL_PAYLOAD_LEN 25
+
+/** Set the buffer at <b>payload_out</b> -- which must have at least
+ * MAX_CONNECTED_CELL_PAYLOAD_LEN bytes available -- to the body of a
+ * RELAY_CONNECTED cell indicating that we have connected to <b>addr</b>, and
+ * that the name resolution that led us to <b>addr</b> will be valid for
+ * <b>ttl</b> seconds. Return -1 on error, or the number of bytes used on
+ * success. */
+STATIC int
+connected_cell_format_payload(uint8_t *payload_out,
+ const tor_addr_t *addr,
+ uint32_t ttl)
+{
+ const sa_family_t family = tor_addr_family(addr);
+ int connected_payload_len;
+
+ /* should be needless */
+ memset(payload_out, 0, MAX_CONNECTED_CELL_PAYLOAD_LEN);
+
+ if (family == AF_INET) {
+ set_uint32(payload_out, tor_addr_to_ipv4n(addr));
+ connected_payload_len = 4;
+ } else if (family == AF_INET6) {
+ set_uint32(payload_out, 0);
+ set_uint8(payload_out + 4, 6);
+ memcpy(payload_out + 5, tor_addr_to_in6_addr8(addr), 16);
+ connected_payload_len = 21;
+ } else {
+ return -1;
+ }
+
+ set_uint32(payload_out + connected_payload_len, htonl(dns_clip_ttl(ttl)));
+ connected_payload_len += 4;
+
+ tor_assert(connected_payload_len <= MAX_CONNECTED_CELL_PAYLOAD_LEN);
+
+ return connected_payload_len;
+}
+
+/* This is an onion service client connection: Export the client circuit ID
+ * according to the HAProxy proxy protocol. */
+STATIC void
+export_hs_client_circuit_id(edge_connection_t *edge_conn,
+ hs_circuit_id_protocol_t protocol)
+{
+ /* We only support HAProxy right now. */
+ if (protocol != HS_CIRCUIT_ID_PROTOCOL_HAPROXY)
+ return;
+
+ char *buf = NULL;
+ const char dst_ipv6[] = "::1";
+ /* See RFC4193 regarding fc00::/7 */
+ const char src_ipv6_prefix[] = "fc00:dead:beef:4dad:";
+ uint16_t dst_port = 0;
+ uint16_t src_port = 1; /* default value */
+ uint32_t gid = 0; /* default value */
+
+ /* Generate a GID and source port for this client */
+ if (edge_conn->on_circuit != NULL) {
+ gid = TO_ORIGIN_CIRCUIT(edge_conn->on_circuit)->global_identifier;
+ src_port = gid & 0x0000ffff;
+ }
+
+ /* Grab the original dest port from the hs ident */
+ if (edge_conn->hs_ident) {
+ dst_port = edge_conn->hs_ident->orig_virtual_port;
+ }
+
+ /* Build the string */
+ tor_asprintf(&buf, "PROXY TCP6 %s:%x:%x %s %d %d\r\n",
+ src_ipv6_prefix,
+ gid >> 16, gid & 0x0000ffff,
+ dst_ipv6, src_port, dst_port);
+
+ connection_buf_add(buf, strlen(buf), TO_CONN(edge_conn));
+
+ tor_free(buf);
+}
+
+/** Connected handler for exit connections: start writing pending
+ * data, deliver 'CONNECTED' relay cells as appropriate, and check
+ * any pending data that may have been received. */
+int
+connection_edge_finished_connecting(edge_connection_t *edge_conn)
+{
+ connection_t *conn;
+
+ tor_assert(edge_conn);
+ tor_assert(edge_conn->base_.type == CONN_TYPE_EXIT);
+ conn = TO_CONN(edge_conn);
+ tor_assert(conn->state == EXIT_CONN_STATE_CONNECTING);
+
+ log_info(LD_EXIT,"Exit connection to %s:%u (%s) established.",
+ escaped_safe_str(conn->address), conn->port,
+ safe_str(fmt_and_decorate_addr(&conn->addr)));
+
+ rep_hist_note_exit_stream_opened(conn->port);
+
+ conn->state = EXIT_CONN_STATE_OPEN;
+
+ connection_watch_events(conn, READ_EVENT); /* stop writing, keep reading */
+ if (connection_get_outbuf_len(conn)) /* in case there are any queued relay
+ * cells */
+ connection_start_writing(conn);
+ /* deliver a 'connected' relay cell back through the circuit. */
+ if (connection_edge_is_rendezvous_stream(edge_conn)) {
+ if (connection_edge_send_command(edge_conn,
+ RELAY_COMMAND_CONNECTED, NULL, 0) < 0)
+ return 0; /* circuit is closed, don't continue */
+ } else {
+ uint8_t connected_payload[MAX_CONNECTED_CELL_PAYLOAD_LEN];
+ int connected_payload_len =
+ connected_cell_format_payload(connected_payload, &conn->addr,
+ edge_conn->address_ttl);
+ if (connected_payload_len < 0)
+ return -1;
+
+ if (connection_edge_send_command(edge_conn,
+ RELAY_COMMAND_CONNECTED,
+ (char*)connected_payload, connected_payload_len) < 0)
+ return 0; /* circuit is closed, don't continue */
+ }
+ tor_assert(edge_conn->package_window > 0);
+ /* in case the server has written anything */
+ return connection_edge_process_inbuf(edge_conn, 1);
+}
+
+/** A list of all the entry_connection_t * objects that are not marked
+ * for close, and are in AP_CONN_STATE_CIRCUIT_WAIT.
+ *
+ * (Right now, we check in several places to make sure that this list is
+ * correct. When it's incorrect, we'll fix it, and log a BUG message.)
+ */
+static smartlist_t *pending_entry_connections = NULL;
+
+static int untried_pending_connections = 0;
+
+/**
+ * Mainloop event to tell us to scan for pending connections that can
+ * be attached.
+ */
+static mainloop_event_t *attach_pending_entry_connections_ev = NULL;
+
+/** Common code to connection_(ap|exit)_about_to_close. */
+static void
+connection_edge_about_to_close(edge_connection_t *edge_conn)
+{
+ if (!edge_conn->edge_has_sent_end) {
+ connection_t *conn = TO_CONN(edge_conn);
+ log_warn(LD_BUG, "(Harmless.) Edge connection (marked at %s:%d) "
+ "hasn't sent end yet?",
+ conn->marked_for_close_file, conn->marked_for_close);
+ tor_fragile_assert();
+ }
+}
+
+/** Called when we're about to finally unlink and free an AP (client)
+ * connection: perform necessary accounting and cleanup */
+void
+connection_ap_about_to_close(entry_connection_t *entry_conn)
+{
+ circuit_t *circ;
+ edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(entry_conn);
+ connection_t *conn = ENTRY_TO_CONN(entry_conn);
+
+ connection_edge_about_to_close(edge_conn);
+
+ if (entry_conn->socks_request->has_finished == 0) {
+ /* since conn gets removed right after this function finishes,
+ * there's no point trying to send back a reply at this point. */
+ log_warn(LD_BUG,"Closing stream (marked at %s:%d) without sending"
+ " back a socks reply.",
+ conn->marked_for_close_file, conn->marked_for_close);
+ }
+ if (!edge_conn->end_reason) {
+ log_warn(LD_BUG,"Closing stream (marked at %s:%d) without having"
+ " set end_reason.",
+ conn->marked_for_close_file, conn->marked_for_close);
+ }
+ if (entry_conn->dns_server_request) {
+ log_warn(LD_BUG,"Closing stream (marked at %s:%d) without having"
+ " replied to DNS request.",
+ conn->marked_for_close_file, conn->marked_for_close);
+ dnsserv_reject_request(entry_conn);
+ }
+
+ if (TO_CONN(edge_conn)->state == AP_CONN_STATE_CIRCUIT_WAIT) {
+ smartlist_remove(pending_entry_connections, entry_conn);
+ }
+
+#if 1
+ /* Check to make sure that this isn't in pending_entry_connections if it
+ * didn't actually belong there. */
+ if (TO_CONN(edge_conn)->type == CONN_TYPE_AP) {
+ connection_ap_warn_and_unmark_if_pending_circ(entry_conn,
+ "about_to_close");
+ }
+#endif /* 1 */
+
+ control_event_stream_bandwidth(edge_conn);
+ control_event_stream_status(entry_conn, STREAM_EVENT_CLOSED,
+ edge_conn->end_reason);
+ circ = circuit_get_by_edge_conn(edge_conn);
+ if (circ)
+ circuit_detach_stream(circ, edge_conn);
+}
+
+/** Called when we're about to finally unlink and free an exit
+ * connection: perform necessary accounting and cleanup */
+void
+connection_exit_about_to_close(edge_connection_t *edge_conn)
+{
+ circuit_t *circ;
+ connection_t *conn = TO_CONN(edge_conn);
+
+ connection_edge_about_to_close(edge_conn);
+
+ circ = circuit_get_by_edge_conn(edge_conn);
+ if (circ)
+ circuit_detach_stream(circ, edge_conn);
+ if (conn->state == EXIT_CONN_STATE_RESOLVING) {
+ connection_dns_remove(edge_conn);
+ }
+}
+
+/** Define a schedule for how long to wait between retrying
+ * application connections. Rather than waiting a fixed amount of
+ * time between each retry, we wait 10 seconds each for the first
+ * two tries, and 15 seconds for each retry after
+ * that. Hopefully this will improve the expected user experience. */
+static int
+compute_retry_timeout(entry_connection_t *conn)
+{
+ int timeout = get_options()->CircuitStreamTimeout;
+ if (timeout) /* if our config options override the default, use them */
+ return timeout;
+ if (conn->num_socks_retries < 2) /* try 0 and try 1 */
+ return 10;
+ return 15;
+}
+
+/** Find all general-purpose AP streams waiting for a response that sent their
+ * begin/resolve cell too long ago. Detach from their current circuit, and
+ * mark their current circuit as unsuitable for new streams. Then call
+ * connection_ap_handshake_attach_circuit() to attach to a new circuit (if
+ * available) or launch a new one.
+ *
+ * For rendezvous streams, simply give up after SocksTimeout seconds (with no
+ * retry attempt).
+ */
+void
+connection_ap_expire_beginning(void)
+{
+ edge_connection_t *conn;
+ entry_connection_t *entry_conn;
+ circuit_t *circ;
+ time_t now = time(NULL);
+ const or_options_t *options = get_options();
+ int severity;
+ int cutoff;
+ int seconds_idle, seconds_since_born;
+ smartlist_t *conns = get_connection_array();
+
+ SMARTLIST_FOREACH_BEGIN(conns, connection_t *, base_conn) {
+ if (base_conn->type != CONN_TYPE_AP || base_conn->marked_for_close)
+ continue;
+ entry_conn = TO_ENTRY_CONN(base_conn);
+ conn = ENTRY_TO_EDGE_CONN(entry_conn);
+ /* if it's an internal linked connection, don't yell its status. */
+ severity = (tor_addr_is_null(&base_conn->addr) && !base_conn->port)
+ ? LOG_INFO : LOG_NOTICE;
+ seconds_idle = (int)( now - base_conn->timestamp_last_read_allowed );
+ seconds_since_born = (int)( now - base_conn->timestamp_created );
+
+ if (base_conn->state == AP_CONN_STATE_OPEN)
+ continue;
+
+ /* We already consider SocksTimeout in
+ * connection_ap_handshake_attach_circuit(), but we need to consider
+ * it here too because controllers that put streams in controller_wait
+ * state never ask Tor to attach the circuit. */
+ if (AP_CONN_STATE_IS_UNATTACHED(base_conn->state)) {
+ if (seconds_since_born >= options->SocksTimeout) {
+ log_fn(severity, LD_APP,
+ "Tried for %d seconds to get a connection to %s:%d. "
+ "Giving up. (%s)",
+ seconds_since_born,
+ safe_str_client(entry_conn->socks_request->address),
+ entry_conn->socks_request->port,
+ conn_state_to_string(CONN_TYPE_AP, base_conn->state));
+ connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT);
+ }
+ continue;
+ }
+
+ /* We're in state connect_wait or resolve_wait now -- waiting for a
+ * reply to our relay cell. See if we want to retry/give up. */
+
+ cutoff = compute_retry_timeout(entry_conn);
+ if (seconds_idle < cutoff)
+ continue;
+ circ = circuit_get_by_edge_conn(conn);
+ if (!circ) { /* it's vanished? */
+ log_info(LD_APP,"Conn is waiting (address %s), but lost its circ.",
+ safe_str_client(entry_conn->socks_request->address));
+ connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT);
+ continue;
+ }
+ if (circ->purpose == CIRCUIT_PURPOSE_C_REND_JOINED) {
+ if (seconds_idle >= options->SocksTimeout) {
+ log_fn(severity, LD_REND,
+ "Rend stream is %d seconds late. Giving up on address"
+ " '%s.onion'.",
+ seconds_idle,
+ safe_str_client(entry_conn->socks_request->address));
+ /* Roll back path bias use state so that we probe the circuit
+ * if nothing else succeeds on it */
+ pathbias_mark_use_rollback(TO_ORIGIN_CIRCUIT(circ));
+
+ connection_edge_end(conn, END_STREAM_REASON_TIMEOUT);
+ connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT);
+ }
+ continue;
+ }
+
+ if (circ->purpose != CIRCUIT_PURPOSE_C_GENERAL &&
+ circ->purpose != CIRCUIT_PURPOSE_C_HSDIR_GET &&
+ circ->purpose != CIRCUIT_PURPOSE_S_HSDIR_POST &&
+ circ->purpose != CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT &&
+ circ->purpose != CIRCUIT_PURPOSE_PATH_BIAS_TESTING) {
+ log_warn(LD_BUG, "circuit->purpose == CIRCUIT_PURPOSE_C_GENERAL failed. "
+ "The purpose on the circuit was %s; it was in state %s, "
+ "path_state %s.",
+ circuit_purpose_to_string(circ->purpose),
+ circuit_state_to_string(circ->state),
+ CIRCUIT_IS_ORIGIN(circ) ?
+ pathbias_state_to_string(TO_ORIGIN_CIRCUIT(circ)->path_state) :
+ "none");
+ }
+ log_fn(cutoff < 15 ? LOG_INFO : severity, LD_APP,
+ "We tried for %d seconds to connect to '%s' using exit %s."
+ " Retrying on a new circuit.",
+ seconds_idle,
+ safe_str_client(entry_conn->socks_request->address),
+ conn->cpath_layer ?
+ extend_info_describe(conn->cpath_layer->extend_info):
+ "*unnamed*");
+ /* send an end down the circuit */
+ connection_edge_end(conn, END_STREAM_REASON_TIMEOUT);
+ /* un-mark it as ending, since we're going to reuse it */
+ conn->edge_has_sent_end = 0;
+ conn->end_reason = 0;
+ /* make us not try this circuit again, but allow
+ * current streams on it to survive if they can */
+ mark_circuit_unusable_for_new_conns(TO_ORIGIN_CIRCUIT(circ));
+
+ /* give our stream another 'cutoff' seconds to try */
+ conn->base_.timestamp_last_read_allowed += cutoff;
+ if (entry_conn->num_socks_retries < 250) /* avoid overflow */
+ entry_conn->num_socks_retries++;
+ /* move it back into 'pending' state, and try to attach. */
+ if (connection_ap_detach_retriable(entry_conn, TO_ORIGIN_CIRCUIT(circ),
+ END_STREAM_REASON_TIMEOUT)<0) {
+ if (!base_conn->marked_for_close)
+ connection_mark_unattached_ap(entry_conn,
+ END_STREAM_REASON_CANT_ATTACH);
+ }
+ } SMARTLIST_FOREACH_END(base_conn);
+}
+
+/**
+ * As connection_ap_attach_pending, but first scans the entire connection
+ * array to see if any elements are missing.
+ */
+void
+connection_ap_rescan_and_attach_pending(void)
+{
+ entry_connection_t *entry_conn;
+ smartlist_t *conns = get_connection_array();
+
+ if (PREDICT_UNLIKELY(NULL == pending_entry_connections))
+ pending_entry_connections = smartlist_new();
+
+ SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) {
+ if (conn->marked_for_close ||
+ conn->type != CONN_TYPE_AP ||
+ conn->state != AP_CONN_STATE_CIRCUIT_WAIT)
+ continue;
+
+ entry_conn = TO_ENTRY_CONN(conn);
+ tor_assert(entry_conn);
+ if (! smartlist_contains(pending_entry_connections, entry_conn)) {
+ log_warn(LD_BUG, "Found a connection %p that was supposed to be "
+ "in pending_entry_connections, but wasn't. No worries; "
+ "adding it.",
+ pending_entry_connections);
+ untried_pending_connections = 1;
+ connection_ap_mark_as_pending_circuit(entry_conn);
+ }
+
+ } SMARTLIST_FOREACH_END(conn);
+
+ connection_ap_attach_pending(1);
+}
+
+#ifdef DEBUGGING_17659
+#define UNMARK() do { \
+ entry_conn->marked_pending_circ_line = 0; \
+ entry_conn->marked_pending_circ_file = 0; \
+ } while (0)
+#else /* !(defined(DEBUGGING_17659)) */
+#define UNMARK() do { } while (0)
+#endif /* defined(DEBUGGING_17659) */
+
+/** Tell any AP streams that are listed as waiting for a new circuit to try
+ * again. If there is an available circuit for a stream, attach it. Otherwise,
+ * launch a new circuit.
+ *
+ * If <b>retry</b> is false, only check the list if it contains at least one
+ * streams that we have not yet tried to attach to a circuit.
+ */
+void
+connection_ap_attach_pending(int retry)
+{
+ if (PREDICT_UNLIKELY(!pending_entry_connections)) {
+ return;
+ }
+
+ if (untried_pending_connections == 0 && !retry)
+ return;
+
+ /* Don't allow any modifications to list while we are iterating over
+ * it. We'll put streams back on this list if we can't attach them
+ * immediately. */
+ smartlist_t *pending = pending_entry_connections;
+ pending_entry_connections = smartlist_new();
+
+ SMARTLIST_FOREACH_BEGIN(pending,
+ entry_connection_t *, entry_conn) {
+ connection_t *conn = ENTRY_TO_CONN(entry_conn);
+ tor_assert(conn && entry_conn);
+ if (conn->marked_for_close) {
+ UNMARK();
+ continue;
+ }
+ if (conn->magic != ENTRY_CONNECTION_MAGIC) {
+ log_warn(LD_BUG, "%p has impossible magic value %u.",
+ entry_conn, (unsigned)conn->magic);
+ UNMARK();
+ continue;
+ }
+ if (conn->state != AP_CONN_STATE_CIRCUIT_WAIT) {
+ log_warn(LD_BUG, "%p is no longer in circuit_wait. Its current state "
+ "is %s. Why is it on pending_entry_connections?",
+ entry_conn,
+ conn_state_to_string(conn->type, conn->state));
+ UNMARK();
+ continue;
+ }
+
+ /* Okay, we're through the sanity checks. Try to handle this stream. */
+ if (connection_ap_handshake_attach_circuit(entry_conn) < 0) {
+ if (!conn->marked_for_close)
+ connection_mark_unattached_ap(entry_conn,
+ END_STREAM_REASON_CANT_ATTACH);
+ }
+
+ if (! conn->marked_for_close &&
+ conn->type == CONN_TYPE_AP &&
+ conn->state == AP_CONN_STATE_CIRCUIT_WAIT) {
+ /* Is it still waiting for a circuit? If so, we didn't attach it,
+ * so it's still pending. Put it back on the list.
+ */
+ if (!smartlist_contains(pending_entry_connections, entry_conn)) {
+ smartlist_add(pending_entry_connections, entry_conn);
+ continue;
+ }
+ }
+
+ /* If we got here, then we either closed the connection, or
+ * we attached it. */
+ UNMARK();
+ } SMARTLIST_FOREACH_END(entry_conn);
+
+ smartlist_free(pending);
+ untried_pending_connections = 0;
+}
+
+static void
+attach_pending_entry_connections_cb(mainloop_event_t *ev, void *arg)
+{
+ (void)ev;
+ (void)arg;
+ connection_ap_attach_pending(0);
+}
+
+/** Mark <b>entry_conn</b> as needing to get attached to a circuit.
+ *
+ * And <b>entry_conn</b> must be in AP_CONN_STATE_CIRCUIT_WAIT,
+ * should not already be pending a circuit. The circuit will get
+ * launched or the connection will get attached the next time we
+ * call connection_ap_attach_pending().
+ */
+void
+connection_ap_mark_as_pending_circuit_(entry_connection_t *entry_conn,
+ const char *fname, int lineno)
+{
+ connection_t *conn = ENTRY_TO_CONN(entry_conn);
+ tor_assert(conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
+ tor_assert(conn->magic == ENTRY_CONNECTION_MAGIC);
+ if (conn->marked_for_close)
+ return;
+
+ if (PREDICT_UNLIKELY(NULL == pending_entry_connections)) {
+ pending_entry_connections = smartlist_new();
+ }
+ if (PREDICT_UNLIKELY(NULL == attach_pending_entry_connections_ev)) {
+ attach_pending_entry_connections_ev = mainloop_event_postloop_new(
+ attach_pending_entry_connections_cb, NULL);
+ }
+ if (PREDICT_UNLIKELY(smartlist_contains(pending_entry_connections,
+ entry_conn))) {
+ log_warn(LD_BUG, "What?? pending_entry_connections already contains %p! "
+ "(Called from %s:%d.)",
+ entry_conn, fname, lineno);
+#ifdef DEBUGGING_17659
+ const char *f2 = entry_conn->marked_pending_circ_file;
+ log_warn(LD_BUG, "(Previously called from %s:%d.)\n",
+ f2 ? f2 : "<NULL>",
+ entry_conn->marked_pending_circ_line);
+#endif /* defined(DEBUGGING_17659) */
+ log_backtrace(LOG_WARN, LD_BUG, "To debug, this may help");
+ return;
+ }
+
+#ifdef DEBUGGING_17659
+ entry_conn->marked_pending_circ_line = (uint16_t) lineno;
+ entry_conn->marked_pending_circ_file = fname;
+#endif
+
+ untried_pending_connections = 1;
+ smartlist_add(pending_entry_connections, entry_conn);
+
+ mainloop_event_activate(attach_pending_entry_connections_ev);
+}
+
+/** Mark <b>entry_conn</b> as no longer waiting for a circuit. */
+void
+connection_ap_mark_as_non_pending_circuit(entry_connection_t *entry_conn)
+{
+ if (PREDICT_UNLIKELY(NULL == pending_entry_connections))
+ return;
+ UNMARK();
+ smartlist_remove(pending_entry_connections, entry_conn);
+}
+
+/** Mark <b>entry_conn</b> as waiting for a rendezvous descriptor. This
+ * function will remove the entry connection from the waiting for a circuit
+ * list (pending_entry_connections).
+ *
+ * This pattern is used across the code base because a connection in state
+ * AP_CONN_STATE_RENDDESC_WAIT must not be in the pending list. */
+void
+connection_ap_mark_as_waiting_for_renddesc(entry_connection_t *entry_conn)
+{
+ tor_assert(entry_conn);
+
+ connection_ap_mark_as_non_pending_circuit(entry_conn);
+ ENTRY_TO_CONN(entry_conn)->state = AP_CONN_STATE_RENDDESC_WAIT;
+}
+
+/* DOCDOC */
+void
+connection_ap_warn_and_unmark_if_pending_circ(entry_connection_t *entry_conn,
+ const char *where)
+{
+ if (pending_entry_connections &&
+ smartlist_contains(pending_entry_connections, entry_conn)) {
+ log_warn(LD_BUG, "What was %p doing in pending_entry_connections in %s?",
+ entry_conn, where);
+ connection_ap_mark_as_non_pending_circuit(entry_conn);
+ }
+}
+
+/** Tell any AP streams that are waiting for a one-hop tunnel to
+ * <b>failed_digest</b> that they are going to fail. */
+/* XXXX We should get rid of this function, and instead attach
+ * one-hop streams to circ->p_streams so they get marked in
+ * circuit_mark_for_close like normal p_streams. */
+void
+connection_ap_fail_onehop(const char *failed_digest,
+ cpath_build_state_t *build_state)
+{
+ entry_connection_t *entry_conn;
+ char digest[DIGEST_LEN];
+ smartlist_t *conns = get_connection_array();
+ SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) {
+ if (conn->marked_for_close ||
+ conn->type != CONN_TYPE_AP ||
+ conn->state != AP_CONN_STATE_CIRCUIT_WAIT)
+ continue;
+ entry_conn = TO_ENTRY_CONN(conn);
+ if (!entry_conn->want_onehop)
+ continue;
+ if (hexdigest_to_digest(entry_conn->chosen_exit_name, digest) < 0 ||
+ tor_memneq(digest, failed_digest, DIGEST_LEN))
+ continue;
+ if (tor_digest_is_zero(digest)) {
+ /* we don't know the digest; have to compare addr:port */
+ tor_addr_t addr;
+ if (!build_state || !build_state->chosen_exit ||
+ !entry_conn->socks_request) {
+ continue;
+ }
+ if (tor_addr_parse(&addr, entry_conn->socks_request->address)<0 ||
+ !tor_addr_eq(&build_state->chosen_exit->addr, &addr) ||
+ build_state->chosen_exit->port != entry_conn->socks_request->port)
+ continue;
+ }
+ log_info(LD_APP, "Closing one-hop stream to '%s/%s' because the OR conn "
+ "just failed.", entry_conn->chosen_exit_name,
+ entry_conn->socks_request->address);
+ connection_mark_unattached_ap(entry_conn, END_STREAM_REASON_TIMEOUT);
+ } SMARTLIST_FOREACH_END(conn);
+}
+
+/** A circuit failed to finish on its last hop <b>info</b>. If there
+ * are any streams waiting with this exit node in mind, but they
+ * don't absolutely require it, make them give up on it.
+ */
+void
+circuit_discard_optional_exit_enclaves(extend_info_t *info)
+{
+ entry_connection_t *entry_conn;
+ const node_t *r1, *r2;
+
+ smartlist_t *conns = get_connection_array();
+ SMARTLIST_FOREACH_BEGIN(conns, connection_t *, conn) {
+ if (conn->marked_for_close ||
+ conn->type != CONN_TYPE_AP ||
+ conn->state != AP_CONN_STATE_CIRCUIT_WAIT)
+ continue;
+ entry_conn = TO_ENTRY_CONN(conn);
+ if (!entry_conn->chosen_exit_optional &&
+ !entry_conn->chosen_exit_retries)
+ continue;
+ r1 = node_get_by_nickname(entry_conn->chosen_exit_name,
+ NNF_NO_WARN_UNNAMED);
+ r2 = node_get_by_id(info->identity_digest);
+ if (!r1 || !r2 || r1 != r2)
+ continue;
+ tor_assert(entry_conn->socks_request);
+ if (entry_conn->chosen_exit_optional) {
+ log_info(LD_APP, "Giving up on enclave exit '%s' for destination %s.",
+ safe_str_client(entry_conn->chosen_exit_name),
+ escaped_safe_str_client(entry_conn->socks_request->address));
+ entry_conn->chosen_exit_optional = 0;
+ tor_free(entry_conn->chosen_exit_name); /* clears it */
+ /* if this port is dangerous, warn or reject it now that we don't
+ * think it'll be using an enclave. */
+ consider_plaintext_ports(entry_conn, entry_conn->socks_request->port);
+ }
+ if (entry_conn->chosen_exit_retries) {
+ if (--entry_conn->chosen_exit_retries == 0) { /* give up! */
+ clear_trackexithost_mappings(entry_conn->chosen_exit_name);
+ tor_free(entry_conn->chosen_exit_name); /* clears it */
+ /* if this port is dangerous, warn or reject it now that we don't
+ * think it'll be using an enclave. */
+ consider_plaintext_ports(entry_conn, entry_conn->socks_request->port);
+ }
+ }
+ } SMARTLIST_FOREACH_END(conn);
+}
+
+/** The AP connection <b>conn</b> has just failed while attaching or
+ * sending a BEGIN or resolving on <b>circ</b>, but another circuit
+ * might work. Detach the circuit, and either reattach it, launch a
+ * new circuit, tell the controller, or give up as appropriate.
+ *
+ * Returns -1 on err, 1 on success, 0 on not-yet-sure.
+ */
+int
+connection_ap_detach_retriable(entry_connection_t *conn,
+ origin_circuit_t *circ,
+ int reason)
+{
+ control_event_stream_status(conn, STREAM_EVENT_FAILED_RETRIABLE, reason);
+ ENTRY_TO_CONN(conn)->timestamp_last_read_allowed = time(NULL);
+
+ /* Roll back path bias use state so that we probe the circuit
+ * if nothing else succeeds on it */
+ pathbias_mark_use_rollback(circ);
+
+ if (conn->pending_optimistic_data) {
+ buf_set_to_copy(&conn->sending_optimistic_data,
+ conn->pending_optimistic_data);
+ }
+
+ if (!get_options()->LeaveStreamsUnattached || conn->use_begindir) {
+ /* If we're attaching streams ourself, or if this connection is
+ * a tunneled directory connection, then just attach it. */
+ ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CIRCUIT_WAIT;
+ circuit_detach_stream(TO_CIRCUIT(circ),ENTRY_TO_EDGE_CONN(conn));
+ connection_ap_mark_as_pending_circuit(conn);
+ } else {
+ CONNECTION_AP_EXPECT_NONPENDING(conn);
+ ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CONTROLLER_WAIT;
+ circuit_detach_stream(TO_CIRCUIT(circ),ENTRY_TO_EDGE_CONN(conn));
+ }
+ return 0;
+}
+
+/** Check if <b>conn</b> is using a dangerous port. Then warn and/or
+ * reject depending on our config options. */
+static int
+consider_plaintext_ports(entry_connection_t *conn, uint16_t port)
+{
+ const or_options_t *options = get_options();
+ int reject = smartlist_contains_int_as_string(
+ options->RejectPlaintextPorts, port);
+
+ if (smartlist_contains_int_as_string(options->WarnPlaintextPorts, port)) {
+ log_warn(LD_APP, "Application request to port %d: this port is "
+ "commonly used for unencrypted protocols. Please make sure "
+ "you don't send anything you would mind the rest of the "
+ "Internet reading!%s", port, reject ? " Closing." : "");
+ control_event_client_status(LOG_WARN, "DANGEROUS_PORT PORT=%d RESULT=%s",
+ port, reject ? "REJECT" : "WARN");
+ }
+
+ if (reject) {
+ log_info(LD_APP, "Port %d listed in RejectPlaintextPorts. Closing.", port);
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ }
+
+ return 0;
+}
+
+/** How many times do we try connecting with an exit configured via
+ * TrackHostExits before concluding that it won't work any more and trying a
+ * different one? */
+#define TRACKHOSTEXITS_RETRIES 5
+
+/** Call connection_ap_handshake_rewrite_and_attach() unless a controller
+ * asked us to leave streams unattached. Return 0 in that case.
+ *
+ * See connection_ap_handshake_rewrite_and_attach()'s
+ * documentation for arguments and return value.
+ */
+MOCK_IMPL(int,
+connection_ap_rewrite_and_attach_if_allowed,(entry_connection_t *conn,
+ origin_circuit_t *circ,
+ crypt_path_t *cpath))
+{
+ const or_options_t *options = get_options();
+
+ if (options->LeaveStreamsUnattached) {
+ CONNECTION_AP_EXPECT_NONPENDING(conn);
+ ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CONTROLLER_WAIT;
+ return 0;
+ }
+ return connection_ap_handshake_rewrite_and_attach(conn, circ, cpath);
+}
+
+/* Try to perform any map-based rewriting of the target address in
+ * <b>conn</b>, filling in the fields of <b>out</b> as we go, and modifying
+ * conn->socks_request.address as appropriate.
+ */
+STATIC void
+connection_ap_handshake_rewrite(entry_connection_t *conn,
+ rewrite_result_t *out)
+{
+ socks_request_t *socks = conn->socks_request;
+ const or_options_t *options = get_options();
+ tor_addr_t addr_tmp;
+
+ /* Initialize all the fields of 'out' to reasonable defaults */
+ out->automap = 0;
+ out->exit_source = ADDRMAPSRC_NONE;
+ out->map_expires = TIME_MAX;
+ out->end_reason = 0;
+ out->should_close = 0;
+ out->orig_address[0] = 0;
+
+ /* We convert all incoming addresses to lowercase. */
+ tor_strlower(socks->address);
+ /* Remember the original address. */
+ strlcpy(out->orig_address, socks->address, sizeof(out->orig_address));
+ log_debug(LD_APP,"Client asked for %s:%d",
+ safe_str_client(socks->address),
+ socks->port);
+
+ /* Check for whether this is a .exit address. By default, those are
+ * disallowed when they're coming straight from the client, but you're
+ * allowed to have them in MapAddress commands and so forth. */
+ if (!strcmpend(socks->address, ".exit")) {
- log_warn(LD_APP, "The \".exit\" notation is disabled in Tor due to "
- "security risks.");
++ static ratelim_t exit_warning_limit = RATELIM_INIT(60*15);
++ log_fn_ratelim(&exit_warning_limit, LOG_WARN, LD_APP,
++ "The \".exit\" notation is disabled in Tor due to "
++ "security risks.");
+ control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
+ escaped(socks->address));
+ out->end_reason = END_STREAM_REASON_TORPROTOCOL;
+ out->should_close = 1;
+ return;
+ }
+
+ /* Remember the original address so we can tell the user about what
+ * they actually said, not just what it turned into. */
+ /* XXX yes, this is the same as out->orig_address above. One is
+ * in the output, and one is in the connection. */
+ if (! conn->original_dest_address) {
+ /* Is the 'if' necessary here? XXXX */
+ conn->original_dest_address = tor_strdup(conn->socks_request->address);
+ }
+
+ /* First, apply MapAddress and MAPADDRESS mappings. We need to do
+ * these only for non-reverse lookups, since they don't exist for those.
+ * We also need to do this before we consider automapping, since we might
+ * e.g. resolve irc.oftc.net into irconionaddress.onion, at which point
+ * we'd need to automap it. */
+ if (socks->command != SOCKS_COMMAND_RESOLVE_PTR) {
+ const unsigned rewrite_flags = AMR_FLAG_USE_MAPADDRESS;
+ if (addressmap_rewrite(socks->address, sizeof(socks->address),
+ rewrite_flags, &out->map_expires, &out->exit_source)) {
+ control_event_stream_status(conn, STREAM_EVENT_REMAP,
+ REMAP_STREAM_SOURCE_CACHE);
+ }
+ }
+
+ /* Now see if we need to create or return an existing Hostname->IP
+ * automapping. Automapping happens when we're asked to resolve a
+ * hostname, and AutomapHostsOnResolve is set, and the hostname has a
+ * suffix listed in AutomapHostsSuffixes. It's a handy feature
+ * that lets you have Tor assign e.g. IPv6 addresses for .onion
+ * names, and return them safely from DNSPort.
+ */
+ if (socks->command == SOCKS_COMMAND_RESOLVE &&
+ tor_addr_parse(&addr_tmp, socks->address)<0 &&
+ options->AutomapHostsOnResolve) {
+ /* Check the suffix... */
+ out->automap = addressmap_address_should_automap(socks->address, options);
+ if (out->automap) {
+ /* If we get here, then we should apply an automapping for this. */
+ const char *new_addr;
+ /* We return an IPv4 address by default, or an IPv6 address if we
+ * are allowed to do so. */
+ int addr_type = RESOLVED_TYPE_IPV4;
+ if (conn->socks_request->socks_version != 4) {
+ if (!conn->entry_cfg.ipv4_traffic ||
+ (conn->entry_cfg.ipv6_traffic && conn->entry_cfg.prefer_ipv6) ||
+ conn->entry_cfg.prefer_ipv6_virtaddr)
+ addr_type = RESOLVED_TYPE_IPV6;
+ }
+ /* Okay, register the target address as automapped, and find the new
+ * address we're supposed to give as a resolve answer. (Return a cached
+ * value if we've looked up this address before.
+ */
+ new_addr = addressmap_register_virtual_address(
+ addr_type, tor_strdup(socks->address));
+ if (! new_addr) {
+ log_warn(LD_APP, "Unable to automap address %s",
+ escaped_safe_str(socks->address));
+ out->end_reason = END_STREAM_REASON_INTERNAL;
+ out->should_close = 1;
+ return;
+ }
+ log_info(LD_APP, "Automapping %s to %s",
+ escaped_safe_str_client(socks->address),
+ safe_str_client(new_addr));
+ strlcpy(socks->address, new_addr, sizeof(socks->address));
+ }
+ }
+
+ /* Now handle reverse lookups, if they're in the cache. This doesn't
+ * happen too often, since client-side DNS caching is off by default,
+ * and very deprecated. */
+ if (socks->command == SOCKS_COMMAND_RESOLVE_PTR) {
+ unsigned rewrite_flags = 0;
+ if (conn->entry_cfg.use_cached_ipv4_answers)
+ rewrite_flags |= AMR_FLAG_USE_IPV4_DNS;
+ if (conn->entry_cfg.use_cached_ipv6_answers)
+ rewrite_flags |= AMR_FLAG_USE_IPV6_DNS;
+
+ if (addressmap_rewrite_reverse(socks->address, sizeof(socks->address),
+ rewrite_flags, &out->map_expires)) {
+ char *result = tor_strdup(socks->address);
+ /* remember _what_ is supposed to have been resolved. */
+ tor_snprintf(socks->address, sizeof(socks->address), "REVERSE[%s]",
+ out->orig_address);
+ connection_ap_handshake_socks_resolved(conn, RESOLVED_TYPE_HOSTNAME,
+ strlen(result), (uint8_t*)result,
+ -1,
+ out->map_expires);
+ tor_free(result);
+ out->end_reason = END_STREAM_REASON_DONE |
+ END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED;
+ out->should_close = 1;
+ return;
+ }
+
+ /* Hang on, did we find an answer saying that this is a reverse lookup for
+ * an internal address? If so, we should reject it if we're configured to
+ * do so. */
+ if (options->ClientDNSRejectInternalAddresses) {
+ /* Don't let clients try to do a reverse lookup on 10.0.0.1. */
+ tor_addr_t addr;
+ int ok;
+ ok = tor_addr_parse_PTR_name(
+ &addr, socks->address, AF_UNSPEC, 1);
+ if (ok == 1 && tor_addr_is_internal(&addr, 0)) {
+ connection_ap_handshake_socks_resolved(conn, RESOLVED_TYPE_ERROR,
+ 0, NULL, -1, TIME_MAX);
+ out->end_reason = END_STREAM_REASON_SOCKSPROTOCOL |
+ END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED;
+ out->should_close = 1;
+ return;
+ }
+ }
+ }
+
+ /* If we didn't automap it before, then this is still the address that
+ * came straight from the user, mapped according to any
+ * MapAddress/MAPADDRESS commands. Now apply other mappings,
+ * including previously registered Automap entries (IP back to
+ * hostname), TrackHostExits entries, and client-side DNS cache
+ * entries (if they're turned on).
+ */
+ if (socks->command != SOCKS_COMMAND_RESOLVE_PTR &&
+ !out->automap) {
+ unsigned rewrite_flags = AMR_FLAG_USE_AUTOMAP | AMR_FLAG_USE_TRACKEXIT;
+ addressmap_entry_source_t exit_source2;
+ if (conn->entry_cfg.use_cached_ipv4_answers)
+ rewrite_flags |= AMR_FLAG_USE_IPV4_DNS;
+ if (conn->entry_cfg.use_cached_ipv6_answers)
+ rewrite_flags |= AMR_FLAG_USE_IPV6_DNS;
+ if (addressmap_rewrite(socks->address, sizeof(socks->address),
+ rewrite_flags, &out->map_expires, &exit_source2)) {
+ control_event_stream_status(conn, STREAM_EVENT_REMAP,
+ REMAP_STREAM_SOURCE_CACHE);
+ }
+ if (out->exit_source == ADDRMAPSRC_NONE) {
+ /* If it wasn't a .exit before, maybe it turned into a .exit. Remember
+ * the original source of a .exit. */
+ out->exit_source = exit_source2;
+ }
+ }
+
+ /* Check to see whether we're about to use an address in the virtual
+ * range without actually having gotten it from an Automap. */
+ if (!out->automap && address_is_in_virtual_range(socks->address)) {
+ /* This address was probably handed out by
+ * client_dns_get_unmapped_address, but the mapping was discarded for some
+ * reason. Or the user typed in a virtual address range manually. We
+ * *don't* want to send the address through Tor; that's likely to fail,
+ * and may leak information.
+ */
+ log_warn(LD_APP,"Missing mapping for virtual address '%s'. Refusing.",
+ safe_str_client(socks->address));
+ out->end_reason = END_STREAM_REASON_INTERNAL;
+ out->should_close = 1;
+ return;
+ }
+}
+
+/** We just received a SOCKS request in <b>conn</b> to an onion address of type
+ * <b>addresstype</b>. Start connecting to the onion service. */
+static int
+connection_ap_handle_onion(entry_connection_t *conn,
+ socks_request_t *socks,
+ origin_circuit_t *circ,
+ hostname_type_t addresstype)
+{
+ time_t now = approx_time();
+ connection_t *base_conn = ENTRY_TO_CONN(conn);
+
+ /* If .onion address requests are disabled, refuse the request */
+ if (!conn->entry_cfg.onion_traffic) {
+ log_warn(LD_APP, "Onion address %s requested from a port with .onion "
+ "disabled", safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ }
+
+ /* Check whether it's RESOLVE or RESOLVE_PTR. We don't handle those
+ * for hidden service addresses. */
+ if (SOCKS_COMMAND_IS_RESOLVE(socks->command)) {
+ /* if it's a resolve request, fail it right now, rather than
+ * building all the circuits and then realizing it won't work. */
+ log_warn(LD_APP,
+ "Resolve requests to hidden services not allowed. Failing.");
+ connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_ERROR,
+ 0,NULL,-1,TIME_MAX);
+ connection_mark_unattached_ap(conn,
+ END_STREAM_REASON_SOCKSPROTOCOL |
+ END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED);
+ return -1;
+ }
+
+ /* If we were passed a circuit, then we need to fail. .onion addresses
+ * only work when we launch our own circuits for now. */
+ if (circ) {
+ log_warn(LD_CONTROL, "Attachstream to a circuit is not "
+ "supported for .onion addresses currently. Failing.");
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+
+ /* Interface: Regardless of HS version after the block below we should have
+ set onion_address, rend_cache_lookup_result, and descriptor_is_usable. */
+ const char *onion_address = NULL;
+ int rend_cache_lookup_result = -ENOENT;
+ int descriptor_is_usable = 0;
+
+ if (addresstype == ONION_V2_HOSTNAME) { /* it's a v2 hidden service */
+ rend_cache_entry_t *entry = NULL;
+ /* Look up if we have client authorization configured for this hidden
+ * service. If we do, associate it with the rend_data. */
+ rend_service_authorization_t *client_auth =
+ rend_client_lookup_service_authorization(socks->address);
+
+ const uint8_t *cookie = NULL;
+ rend_auth_type_t auth_type = REND_NO_AUTH;
+ if (client_auth) {
+ log_info(LD_REND, "Using previously configured client authorization "
+ "for hidden service request.");
+ auth_type = client_auth->auth_type;
+ cookie = client_auth->descriptor_cookie;
+ }
+
+ /* Fill in the rend_data field so we can start doing a connection to
+ * a hidden service. */
+ rend_data_t *rend_data = ENTRY_TO_EDGE_CONN(conn)->rend_data =
+ rend_data_client_create(socks->address, NULL, (char *) cookie,
+ auth_type);
+ if (rend_data == NULL) {
+ return -1;
+ }
+ onion_address = rend_data_get_address(rend_data);
+ log_info(LD_REND,"Got a hidden service request for ID '%s'",
+ safe_str_client(onion_address));
+
+ rend_cache_lookup_result = rend_cache_lookup_entry(onion_address,-1,
+ &entry);
+ if (!rend_cache_lookup_result && entry) {
+ descriptor_is_usable = rend_client_any_intro_points_usable(entry);
+ }
+ } else { /* it's a v3 hidden service */
+ tor_assert(addresstype == ONION_V3_HOSTNAME);
+ const hs_descriptor_t *cached_desc = NULL;
+ int retval;
+ /* Create HS conn identifier with HS pubkey */
+ hs_ident_edge_conn_t *hs_conn_ident =
+ tor_malloc_zero(sizeof(hs_ident_edge_conn_t));
+
+ retval = hs_parse_address(socks->address, &hs_conn_ident->identity_pk,
+ NULL, NULL);
+ if (retval < 0) {
+ log_warn(LD_GENERAL, "failed to parse hs address");
+ tor_free(hs_conn_ident);
+ return -1;
+ }
+ ENTRY_TO_EDGE_CONN(conn)->hs_ident = hs_conn_ident;
+
+ onion_address = socks->address;
+
+ /* Check the v3 desc cache */
+ cached_desc = hs_cache_lookup_as_client(&hs_conn_ident->identity_pk);
+ if (cached_desc) {
+ rend_cache_lookup_result = 0;
+ descriptor_is_usable =
+ hs_client_any_intro_points_usable(&hs_conn_ident->identity_pk,
+ cached_desc);
+ log_info(LD_GENERAL, "Found %s descriptor in cache for %s. %s.",
+ (descriptor_is_usable) ? "usable" : "unusable",
+ safe_str_client(onion_address),
+ (descriptor_is_usable) ? "Not fetching." : "Refecting.");
+ } else {
+ rend_cache_lookup_result = -ENOENT;
+ }
+ }
+
+ /* Lookup the given onion address. If invalid, stop right now.
+ * Otherwise, we might have it in the cache or not. */
+ unsigned int refetch_desc = 0;
+ if (rend_cache_lookup_result < 0) {
+ switch (-rend_cache_lookup_result) {
+ case EINVAL:
+ /* We should already have rejected this address! */
+ log_warn(LD_BUG,"Invalid service name '%s'",
+ safe_str_client(onion_address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ case ENOENT:
+ /* We didn't have this; we should look it up. */
+ log_info(LD_REND, "No descriptor found in our cache for %s. Fetching.",
+ safe_str_client(onion_address));
+ refetch_desc = 1;
+ break;
+ default:
+ log_warn(LD_BUG, "Unknown cache lookup error %d",
+ rend_cache_lookup_result);
+ return -1;
+ }
+ }
+
+ /* Help predict that we'll want to do hidden service circuits in the
+ * future. We're not sure if it will need a stable circuit yet, but
+ * we know we'll need *something*. */
+ rep_hist_note_used_internal(now, 0, 1);
+
+ /* Now we have a descriptor but is it usable or not? If not, refetch.
+ * Also, a fetch could have been requested if the onion address was not
+ * found in the cache previously. */
+ if (refetch_desc || !descriptor_is_usable) {
+ edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(conn);
+ connection_ap_mark_as_non_pending_circuit(conn);
+ base_conn->state = AP_CONN_STATE_RENDDESC_WAIT;
+ if (addresstype == ONION_V2_HOSTNAME) {
+ tor_assert(edge_conn->rend_data);
+ rend_client_refetch_v2_renddesc(edge_conn->rend_data);
+ /* Whatever the result of the refetch, we don't go further. */
+ return 0;
+ } else {
+ tor_assert(addresstype == ONION_V3_HOSTNAME);
+ tor_assert(edge_conn->hs_ident);
+ /* Attempt to fetch the hsv3 descriptor. Check the retval to see how it
+ * went and act accordingly. */
+ int ret = hs_client_refetch_hsdesc(&edge_conn->hs_ident->identity_pk);
+ switch (ret) {
+ case HS_CLIENT_FETCH_MISSING_INFO:
+ /* Keeping the connection in descriptor wait state is fine because
+ * once we get enough dirinfo or a new live consensus, the HS client
+ * subsystem is notified and every connection in that state will
+ * trigger a fetch for the service key. */
+ case HS_CLIENT_FETCH_LAUNCHED:
+ case HS_CLIENT_FETCH_PENDING:
+ case HS_CLIENT_FETCH_HAVE_DESC:
+ return 0;
+ case HS_CLIENT_FETCH_ERROR:
+ case HS_CLIENT_FETCH_NO_HSDIRS:
+ case HS_CLIENT_FETCH_NOT_ALLOWED:
+ /* Can't proceed further and better close the SOCKS request. */
+ return -1;
+ }
+ }
+ }
+
+ /* We have the descriptor! So launch a connection to the HS. */
+ log_info(LD_REND, "Descriptor is here. Great.");
+
+ base_conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
+ /* We'll try to attach it at the next event loop, or whenever
+ * we call connection_ap_attach_pending() */
+ connection_ap_mark_as_pending_circuit(conn);
+ return 0;
+}
+
+/** Connection <b>conn</b> just finished its socks handshake, or the
+ * controller asked us to take care of it. If <b>circ</b> is defined,
+ * then that's where we'll want to attach it. Otherwise we have to
+ * figure it out ourselves.
+ *
+ * First, parse whether it's a .exit address, remap it, and so on. Then
+ * if it's for a general circuit, try to attach it to a circuit (or launch
+ * one as needed), else if it's for a rendezvous circuit, fetch a
+ * rendezvous descriptor first (or attach/launch a circuit if the
+ * rendezvous descriptor is already here and fresh enough).
+ *
+ * The stream will exit from the hop
+ * indicated by <b>cpath</b>, or from the last hop in circ's cpath if
+ * <b>cpath</b> is NULL.
+ */
+int
+connection_ap_handshake_rewrite_and_attach(entry_connection_t *conn,
+ origin_circuit_t *circ,
+ crypt_path_t *cpath)
+{
+ socks_request_t *socks = conn->socks_request;
+ const or_options_t *options = get_options();
+ connection_t *base_conn = ENTRY_TO_CONN(conn);
+ time_t now = time(NULL);
+ rewrite_result_t rr;
+
+ /* First we'll do the rewrite part. Let's see if we get a reasonable
+ * answer.
+ */
+ memset(&rr, 0, sizeof(rr));
+ connection_ap_handshake_rewrite(conn,&rr);
+
+ if (rr.should_close) {
+ /* connection_ap_handshake_rewrite told us to close the connection:
+ * either because it sent back an answer, or because it sent back an
+ * error */
+ connection_mark_unattached_ap(conn, rr.end_reason);
+ if (END_STREAM_REASON_DONE == (rr.end_reason & END_STREAM_REASON_MASK))
+ return 0;
+ else
+ return -1;
+ }
+
+ const time_t map_expires = rr.map_expires;
+ const int automap = rr.automap;
+ const addressmap_entry_source_t exit_source = rr.exit_source;
+
+ /* Now, we parse the address to see if it's an .onion or .exit or
+ * other special address.
+ */
+ const hostname_type_t addresstype = parse_extended_hostname(socks->address);
+
+ /* Now see whether the hostname is bogus. This could happen because of an
+ * onion hostname whose format we don't recognize. */
+ if (addresstype == BAD_HOSTNAME) {
+ control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
+ escaped(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+
+ /* If this is a .exit hostname, strip off the .name.exit part, and
+ * see whether we're willing to connect there, and and otherwise handle the
+ * .exit address.
+ *
+ * We'll set chosen_exit_name and/or close the connection as appropriate.
+ */
+ if (addresstype == EXIT_HOSTNAME) {
+ /* If StrictNodes is not set, then .exit overrides ExcludeNodes but
+ * not ExcludeExitNodes. */
+ routerset_t *excludeset = options->StrictNodes ?
+ options->ExcludeExitNodesUnion_ : options->ExcludeExitNodes;
+ const node_t *node = NULL;
+
+ /* If this .exit was added by an AUTOMAP, then it came straight from
+ * a user. That's not safe. */
+ if (exit_source == ADDRMAPSRC_AUTOMAP) {
+ /* Whoops; this one is stale. It must have gotten added earlier?
+ * (Probably this is not possible, since AllowDotExit no longer
+ * exists.) */
+ log_warn(LD_APP,"Stale automapped address for '%s.exit'. Refusing.",
+ safe_str_client(socks->address));
+ control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
+ escaped(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ tor_assert_nonfatal_unreached();
+ return -1;
+ }
+
+ /* Double-check to make sure there are no .exits coming from
+ * impossible/weird sources. */
+ if (exit_source == ADDRMAPSRC_DNS || exit_source == ADDRMAPSRC_NONE) {
+ /* It shouldn't be possible to get a .exit address from any of these
+ * sources. */
+ log_warn(LD_BUG,"Address '%s.exit', with impossible source for the "
+ ".exit part. Refusing.",
+ safe_str_client(socks->address));
+ control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
+ escaped(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+
+ tor_assert(!automap);
+
+ /* Now, find the character before the .(name) part.
+ * (The ".exit" part got stripped off by "parse_extended_hostname").
+ *
+ * We're going to put the exit name into conn->chosen_exit_name, and
+ * look up a node correspondingly. */
+ char *s = strrchr(socks->address,'.');
+ if (s) {
+ /* The address was of the form "(stuff).(name).exit */
+ if (s[1] != '\0') {
+ /* Looks like a real .exit one. */
+ conn->chosen_exit_name = tor_strdup(s+1);
+ node = node_get_by_nickname(conn->chosen_exit_name, 0);
+
+ if (exit_source == ADDRMAPSRC_TRACKEXIT) {
+ /* We 5 tries before it expires the addressmap */
+ conn->chosen_exit_retries = TRACKHOSTEXITS_RETRIES;
+ }
+ *s = 0;
+ } else {
+ /* Oops, the address was (stuff)..exit. That's not okay. */
+ log_warn(LD_APP,"Malformed exit address '%s.exit'. Refusing.",
+ safe_str_client(socks->address));
+ control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
+ escaped(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+ } else {
+ /* It looks like they just asked for "foo.exit". That's a special
+ * form that means (foo's address).foo.exit. */
+
+ conn->chosen_exit_name = tor_strdup(socks->address);
+ node = node_get_by_nickname(conn->chosen_exit_name, 0);
+ if (node) {
+ *socks->address = 0;
+ node_get_address_string(node, socks->address, sizeof(socks->address));
+ }
+ }
+
+ /* Now make sure that the chosen exit exists... */
+ if (!node) {
+ log_warn(LD_APP,
+ "Unrecognized relay in exit address '%s.exit'. Refusing.",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+ /* ...and make sure that it isn't excluded. */
+ if (routerset_contains_node(excludeset, node)) {
+ log_warn(LD_APP,
+ "Excluded relay in exit address '%s.exit'. Refusing.",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+ /* XXXX-1090 Should we also allow foo.bar.exit if ExitNodes is set and
+ Bar is not listed in it? I say yes, but our revised manpage branch
+ implies no. */
+ }
+
+ /* Now, we handle everything that isn't a .onion address. */
+ if (addresstype != ONION_V2_HOSTNAME && addresstype != ONION_V3_HOSTNAME) {
+ /* Not a hidden-service request. It's either a hostname or an IP,
+ * possibly with a .exit that we stripped off. We're going to check
+ * if we're allowed to connect/resolve there, and then launch the
+ * appropriate request. */
+
+ /* Check for funny characters in the address. */
+ if (address_is_invalid_destination(socks->address, 1)) {
+ control_event_client_status(LOG_WARN, "SOCKS_BAD_HOSTNAME HOSTNAME=%s",
+ escaped(socks->address));
+ log_warn(LD_APP,
+ "Destination '%s' seems to be an invalid hostname. Failing.",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+
+ /* socks->address is a non-onion hostname or IP address.
+ * If we can't do any non-onion requests, refuse the connection.
+ * If we have a hostname but can't do DNS, refuse the connection.
+ * If we have an IP address, but we can't use that address family,
+ * refuse the connection.
+ *
+ * If we can do DNS requests, and we can use at least one address family,
+ * then we have to resolve the address first. Then we'll know if it
+ * resolves to a usable address family. */
+
+ /* First, check if all non-onion traffic is disabled */
+ if (!conn->entry_cfg.dns_request && !conn->entry_cfg.ipv4_traffic
+ && !conn->entry_cfg.ipv6_traffic) {
+ log_warn(LD_APP, "Refusing to connect to non-hidden-service hostname "
+ "or IP address %s because Port has OnionTrafficOnly set (or "
+ "NoDNSRequest, NoIPv4Traffic, and NoIPv6Traffic).",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ }
+
+ /* Then check if we have a hostname or IP address, and whether DNS or
+ * the IP address family are permitted. Reject if not. */
+ tor_addr_t dummy_addr;
+ int socks_family = tor_addr_parse(&dummy_addr, socks->address);
+ /* family will be -1 for a non-onion hostname that's not an IP */
+ if (socks_family == -1) {
+ if (!conn->entry_cfg.dns_request) {
+ log_warn(LD_APP, "Refusing to connect to hostname %s "
+ "because Port has NoDNSRequest set.",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ }
+ } else if (socks_family == AF_INET) {
+ if (!conn->entry_cfg.ipv4_traffic) {
+ log_warn(LD_APP, "Refusing to connect to IPv4 address %s because "
+ "Port has NoIPv4Traffic set.",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ }
+ } else if (socks_family == AF_INET6) {
+ if (!conn->entry_cfg.ipv6_traffic) {
+ log_warn(LD_APP, "Refusing to connect to IPv6 address %s because "
+ "Port has NoIPv6Traffic set.",
+ safe_str_client(socks->address));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ }
+ } else {
+ tor_assert_nonfatal_unreached_once();
+ }
+
+ /* See if this is a hostname lookup that we can answer immediately.
+ * (For example, an attempt to look up the IP address for an IP address.)
+ */
+ if (socks->command == SOCKS_COMMAND_RESOLVE) {
+ tor_addr_t answer;
+ /* Reply to resolves immediately if we can. */
+ if (tor_addr_parse(&answer, socks->address) >= 0) {/* is it an IP? */
+ /* remember _what_ is supposed to have been resolved. */
+ strlcpy(socks->address, rr.orig_address, sizeof(socks->address));
+ connection_ap_handshake_socks_resolved_addr(conn, &answer, -1,
+ map_expires);
+ connection_mark_unattached_ap(conn,
+ END_STREAM_REASON_DONE |
+ END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED);
+ return 0;
+ }
+ tor_assert(!automap);
+ rep_hist_note_used_resolve(now); /* help predict this next time */
+ } else if (socks->command == SOCKS_COMMAND_CONNECT) {
+ /* Now see if this is a connect request that we can reject immediately */
+
+ tor_assert(!automap);
+ /* Don't allow connections to port 0. */
+ if (socks->port == 0) {
+ log_notice(LD_APP,"Application asked to connect to port 0. Refusing.");
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL);
+ return -1;
+ }
+ /* You can't make connections to internal addresses, by default.
+ * Exceptions are begindir requests (where the address is meaningless),
+ * or cases where you've hand-configured a particular exit, thereby
+ * making the local address meaningful. */
+ if (options->ClientRejectInternalAddresses &&
+ !conn->use_begindir && !conn->chosen_exit_name && !circ) {
+ /* If we reach this point then we don't want to allow internal
+ * addresses. Check if we got one. */
+ tor_addr_t addr;
+ if (tor_addr_hostname_is_local(socks->address) ||
+ (tor_addr_parse(&addr, socks->address) >= 0 &&
+ tor_addr_is_internal(&addr, 0))) {
+ /* If this is an explicit private address with no chosen exit node,
+ * then we really don't want to try to connect to it. That's
+ * probably an error. */
+ if (conn->is_transparent_ap) {
+#define WARN_INTRVL_LOOP 300
+ static ratelim_t loop_warn_limit = RATELIM_INIT(WARN_INTRVL_LOOP);
+ char *m;
+ if ((m = rate_limit_log(&loop_warn_limit, approx_time()))) {
+ log_warn(LD_NET,
+ "Rejecting request for anonymous connection to private "
+ "address %s on a TransPort or NATDPort. Possible loop "
+ "in your NAT rules?%s", safe_str_client(socks->address),
+ m);
+ tor_free(m);
+ }
+ } else {
+#define WARN_INTRVL_PRIV 300
+ static ratelim_t priv_warn_limit = RATELIM_INIT(WARN_INTRVL_PRIV);
+ char *m;
+ if ((m = rate_limit_log(&priv_warn_limit, approx_time()))) {
+ log_warn(LD_NET,
+ "Rejecting SOCKS request for anonymous connection to "
+ "private address %s.%s",
+ safe_str_client(socks->address),m);
+ tor_free(m);
+ }
+ }
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_PRIVATE_ADDR);
+ return -1;
+ }
+ } /* end "if we should check for internal addresses" */
+
+ /* Okay. We're still doing a CONNECT, and it wasn't a private
+ * address. Here we do special handling for literal IP addresses,
+ * to see if we should reject this preemptively, and to set up
+ * fields in conn->entry_cfg to tell the exit what AF we want. */
+ {
+ tor_addr_t addr;
+ /* XXX Duplicate call to tor_addr_parse. */
+ if (tor_addr_parse(&addr, socks->address) >= 0) {
+ /* If we reach this point, it's an IPv4 or an IPv6 address. */
+ sa_family_t family = tor_addr_family(&addr);
+
+ if ((family == AF_INET && ! conn->entry_cfg.ipv4_traffic) ||
+ (family == AF_INET6 && ! conn->entry_cfg.ipv6_traffic)) {
+ /* You can't do an IPv4 address on a v6-only socks listener,
+ * or vice versa. */
+ log_warn(LD_NET, "Rejecting SOCKS request for an IP address "
+ "family that this listener does not support.");
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ } else if (family == AF_INET6 && socks->socks_version == 4) {
+ /* You can't make a socks4 request to an IPv6 address. Socks4
+ * doesn't support that. */
+ log_warn(LD_NET, "Rejecting SOCKS4 request for an IPv6 address.");
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ } else if (socks->socks_version == 4 &&
+ !conn->entry_cfg.ipv4_traffic) {
+ /* You can't do any kind of Socks4 request when IPv4 is forbidden.
+ *
+ * XXX raise this check outside the enclosing block? */
+ log_warn(LD_NET, "Rejecting SOCKS4 request on a listener with "
+ "no IPv4 traffic supported.");
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_ENTRYPOLICY);
+ return -1;
+ } else if (family == AF_INET6) {
+ /* Tell the exit: we won't accept any ipv4 connection to an IPv6
+ * address. */
+ conn->entry_cfg.ipv4_traffic = 0;
+ } else if (family == AF_INET) {
+ /* Tell the exit: we won't accept any ipv6 connection to an IPv4
+ * address. */
+ conn->entry_cfg.ipv6_traffic = 0;
+ }
+ }
+ }
+
+ /* we never allow IPv6 answers on socks4. (TODO: Is this smart?) */
+ if (socks->socks_version == 4)
+ conn->entry_cfg.ipv6_traffic = 0;
+
+ /* Still handling CONNECT. Now, check for exit enclaves. (Which we
+ * don't do on BEGIN_DIR, or when there is a chosen exit.)
+ *
+ * TODO: Should we remove this? Exit enclaves are nutty and don't
+ * work very well
+ */
+ if (!conn->use_begindir && !conn->chosen_exit_name && !circ) {
+ /* see if we can find a suitable enclave exit */
+ const node_t *r =
+ router_find_exact_exit_enclave(socks->address, socks->port);
+ if (r) {
+ log_info(LD_APP,
+ "Redirecting address %s to exit at enclave router %s",
+ safe_str_client(socks->address), node_describe(r));
+ /* use the hex digest, not nickname, in case there are two
+ routers with this nickname */
+ conn->chosen_exit_name =
+ tor_strdup(hex_str(r->identity, DIGEST_LEN));
+ conn->chosen_exit_optional = 1;
+ }
+ }
+
+ /* Still handling CONNECT: warn or reject if it's using a dangerous
+ * port. */
+ if (!conn->use_begindir && !conn->chosen_exit_name && !circ)
+ if (consider_plaintext_ports(conn, socks->port) < 0)
+ return -1;
+
+ /* Remember the port so that we will predict that more requests
+ there will happen in the future. */
+ if (!conn->use_begindir) {
+ /* help predict this next time */
+ rep_hist_note_used_port(now, socks->port);
+ }
+ } else if (socks->command == SOCKS_COMMAND_RESOLVE_PTR) {
+ rep_hist_note_used_resolve(now); /* help predict this next time */
+ /* no extra processing needed */
+ } else {
+ /* We should only be doing CONNECT, RESOLVE, or RESOLVE_PTR! */
+ tor_fragile_assert();
+ }
+
+ /* Okay. At this point we've set chosen_exit_name if needed, rewritten the
+ * address, and decided not to reject it for any number of reasons. Now
+ * mark the connection as waiting for a circuit, and try to attach it!
+ */
+ base_conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
+
+ /* If we were given a circuit to attach to, try to attach. Otherwise,
+ * try to find a good one and attach to that. */
+ int rv;
+ if (circ) {
+ rv = connection_ap_handshake_attach_chosen_circuit(conn, circ, cpath);
+ } else {
+ /* We'll try to attach it at the next event loop, or whenever
+ * we call connection_ap_attach_pending() */
+ connection_ap_mark_as_pending_circuit(conn);
+ rv = 0;
+ }
+
+ /* If the above function returned 0 then we're waiting for a circuit.
+ * if it returned 1, we're attached. Both are okay. But if it returned
+ * -1, there was an error, so make sure the connection is marked, and
+ * return -1. */
+ if (rv < 0) {
+ if (!base_conn->marked_for_close)
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_CANT_ATTACH);
+ return -1;
+ }
+
+ return 0;
+ } else {
+ /* If we get here, it's a request for a .onion address! */
+ tor_assert(addresstype == ONION_V2_HOSTNAME ||
+ addresstype == ONION_V3_HOSTNAME);
+ tor_assert(!automap);
+ return connection_ap_handle_onion(conn, socks, circ, addresstype);
+ }
+
+ return 0; /* unreached but keeps the compiler happy */
+}
+
+#ifdef TRANS_PF
+static int pf_socket = -1;
+int
+get_pf_socket(void)
+{
+ int pf;
+ /* This should be opened before dropping privileges. */
+ if (pf_socket >= 0)
+ return pf_socket;
+
+#if defined(OpenBSD)
+ /* only works on OpenBSD */
+ pf = tor_open_cloexec("/dev/pf", O_RDONLY, 0);
+#else
+ /* works on NetBSD and FreeBSD */
+ pf = tor_open_cloexec("/dev/pf", O_RDWR, 0);
+#endif /* defined(OpenBSD) */
+
+ if (pf < 0) {
+ log_warn(LD_NET, "open(\"/dev/pf\") failed: %s", strerror(errno));
+ return -1;
+ }
+
+ pf_socket = pf;
+ return pf_socket;
+}
+#endif /* defined(TRANS_PF) */
+
+#if defined(TRANS_NETFILTER) || defined(TRANS_PF) || \
+ defined(TRANS_TPROXY)
+/** Try fill in the address of <b>req</b> from the socket configured
+ * with <b>conn</b>. */
+static int
+destination_from_socket(entry_connection_t *conn, socks_request_t *req)
+{
+ struct sockaddr_storage orig_dst;
+ socklen_t orig_dst_len = sizeof(orig_dst);
+ tor_addr_t addr;
+
+#ifdef TRANS_TPROXY
+ if (get_options()->TransProxyType_parsed == TPT_TPROXY) {
+ if (getsockname(ENTRY_TO_CONN(conn)->s, (struct sockaddr*)&orig_dst,
+ &orig_dst_len) < 0) {
+ int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s);
+ log_warn(LD_NET, "getsockname() failed: %s", tor_socket_strerror(e));
+ return -1;
+ }
+ goto done;
+ }
+#endif /* defined(TRANS_TPROXY) */
+
+#ifdef TRANS_NETFILTER
+ int rv = -1;
+ switch (ENTRY_TO_CONN(conn)->socket_family) {
+#ifdef TRANS_NETFILTER_IPV4
+ case AF_INET:
+ rv = getsockopt(ENTRY_TO_CONN(conn)->s, SOL_IP, SO_ORIGINAL_DST,
+ (struct sockaddr*)&orig_dst, &orig_dst_len);
+ break;
+#endif /* defined(TRANS_NETFILTER_IPV4) */
+#ifdef TRANS_NETFILTER_IPV6
+ case AF_INET6:
+ rv = getsockopt(ENTRY_TO_CONN(conn)->s, SOL_IPV6, IP6T_SO_ORIGINAL_DST,
+ (struct sockaddr*)&orig_dst, &orig_dst_len);
+ break;
+#endif /* defined(TRANS_NETFILTER_IPV6) */
+ default:
+ log_warn(LD_BUG,
+ "Received transparent data from an unsuported socket family %d",
+ ENTRY_TO_CONN(conn)->socket_family);
+ return -1;
+ }
+ if (rv < 0) {
+ int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s);
+ log_warn(LD_NET, "getsockopt() failed: %s", tor_socket_strerror(e));
+ return -1;
+ }
+ goto done;
+#elif defined(TRANS_PF)
+ if (getsockname(ENTRY_TO_CONN(conn)->s, (struct sockaddr*)&orig_dst,
+ &orig_dst_len) < 0) {
+ int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s);
+ log_warn(LD_NET, "getsockname() failed: %s", tor_socket_strerror(e));
+ return -1;
+ }
+ goto done;
+#else
+ (void)conn;
+ (void)req;
+ log_warn(LD_BUG, "Unable to determine destination from socket.");
+ return -1;
+#endif /* defined(TRANS_NETFILTER) || ... */
+
+ done:
+ tor_addr_from_sockaddr(&addr, (struct sockaddr*)&orig_dst, &req->port);
+ tor_addr_to_str(req->address, &addr, sizeof(req->address), 1);
+
+ return 0;
+}
+#endif /* defined(TRANS_NETFILTER) || defined(TRANS_PF) || ... */
+
+#ifdef TRANS_PF
+static int
+destination_from_pf(entry_connection_t *conn, socks_request_t *req)
+{
+ struct sockaddr_storage proxy_addr;
+ socklen_t proxy_addr_len = sizeof(proxy_addr);
+ struct sockaddr *proxy_sa = (struct sockaddr*) &proxy_addr;
+ struct pfioc_natlook pnl;
+ tor_addr_t addr;
+ int pf = -1;
+
+ if (getsockname(ENTRY_TO_CONN(conn)->s, (struct sockaddr*)&proxy_addr,
+ &proxy_addr_len) < 0) {
+ int e = tor_socket_errno(ENTRY_TO_CONN(conn)->s);
+ log_warn(LD_NET, "getsockname() to determine transocks destination "
+ "failed: %s", tor_socket_strerror(e));
+ return -1;
+ }
+
+#ifdef __FreeBSD__
+ if (get_options()->TransProxyType_parsed == TPT_IPFW) {
+ /* ipfw(8) is used and in this case getsockname returned the original
+ destination */
+ if (tor_addr_from_sockaddr(&addr, proxy_sa, &req->port) < 0) {
+ tor_fragile_assert();
+ return -1;
+ }
+
+ tor_addr_to_str(req->address, &addr, sizeof(req->address), 0);
+
+ return 0;
+ }
+#endif /* defined(__FreeBSD__) */
+
+ memset(&pnl, 0, sizeof(pnl));
+ pnl.proto = IPPROTO_TCP;
+ pnl.direction = PF_OUT;
+ if (proxy_sa->sa_family == AF_INET) {
+ struct sockaddr_in *sin = (struct sockaddr_in *)proxy_sa;
+ pnl.af = AF_INET;
+ pnl.saddr.v4.s_addr = tor_addr_to_ipv4n(&ENTRY_TO_CONN(conn)->addr);
+ pnl.sport = htons(ENTRY_TO_CONN(conn)->port);
+ pnl.daddr.v4.s_addr = sin->sin_addr.s_addr;
+ pnl.dport = sin->sin_port;
+ } else if (proxy_sa->sa_family == AF_INET6) {
+ struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)proxy_sa;
+ pnl.af = AF_INET6;
+ const struct in6_addr *dest_in6 =
+ tor_addr_to_in6(&ENTRY_TO_CONN(conn)->addr);
+ if (BUG(!dest_in6))
+ return -1;
+ memcpy(&pnl.saddr.v6, dest_in6, sizeof(struct in6_addr));
+ pnl.sport = htons(ENTRY_TO_CONN(conn)->port);
+ memcpy(&pnl.daddr.v6, &sin6->sin6_addr, sizeof(struct in6_addr));
+ pnl.dport = sin6->sin6_port;
+ } else {
+ log_warn(LD_NET, "getsockname() gave an unexpected address family (%d)",
+ (int)proxy_sa->sa_family);
+ return -1;
+ }
+
+ pf = get_pf_socket();
+ if (pf<0)
+ return -1;
+
+ if (ioctl(pf, DIOCNATLOOK, &pnl) < 0) {
+ log_warn(LD_NET, "ioctl(DIOCNATLOOK) failed: %s", strerror(errno));
+ return -1;
+ }
+
+ if (pnl.af == AF_INET) {
+ tor_addr_from_ipv4n(&addr, pnl.rdaddr.v4.s_addr);
+ } else if (pnl.af == AF_INET6) {
+ tor_addr_from_in6(&addr, &pnl.rdaddr.v6);
+ } else {
+ tor_fragile_assert();
+ return -1;
+ }
+
+ tor_addr_to_str(req->address, &addr, sizeof(req->address), 1);
+ req->port = ntohs(pnl.rdport);
+
+ return 0;
+}
+#endif /* defined(TRANS_PF) */
+
+/** Fetch the original destination address and port from a
+ * system-specific interface and put them into a
+ * socks_request_t as if they came from a socks request.
+ *
+ * Return -1 if an error prevents fetching the destination,
+ * else return 0.
+ */
+static int
+connection_ap_get_original_destination(entry_connection_t *conn,
+ socks_request_t *req)
+{
+#ifdef TRANS_NETFILTER
+ return destination_from_socket(conn, req);
+#elif defined(TRANS_PF)
+ const or_options_t *options = get_options();
+
+ if (options->TransProxyType_parsed == TPT_PF_DIVERT)
+ return destination_from_socket(conn, req);
+
+ if (options->TransProxyType_parsed == TPT_DEFAULT ||
+ options->TransProxyType_parsed == TPT_IPFW)
+ return destination_from_pf(conn, req);
+
+ (void)conn;
+ (void)req;
+ log_warn(LD_BUG, "Proxy destination determination mechanism %s unknown.",
+ options->TransProxyType);
+ return -1;
+#else
+ (void)conn;
+ (void)req;
+ log_warn(LD_BUG, "Called connection_ap_get_original_destination, but no "
+ "transparent proxy method was configured.");
+ return -1;
+#endif /* defined(TRANS_NETFILTER) || ... */
+}
+
+/** connection_edge_process_inbuf() found a conn in state
+ * socks_wait. See if conn->inbuf has the right bytes to proceed with
+ * the socks handshake.
+ *
+ * If the handshake is complete, send it to
+ * connection_ap_handshake_rewrite_and_attach().
+ *
+ * Return -1 if an unexpected error with conn occurs (and mark it for close),
+ * else return 0.
+ */
+static int
+connection_ap_handshake_process_socks(entry_connection_t *conn)
+{
+ socks_request_t *socks;
+ int sockshere;
+ const or_options_t *options = get_options();
+ int had_reply = 0;
+ connection_t *base_conn = ENTRY_TO_CONN(conn);
+
+ tor_assert(conn);
+ tor_assert(base_conn->type == CONN_TYPE_AP);
+ tor_assert(base_conn->state == AP_CONN_STATE_SOCKS_WAIT);
+ tor_assert(conn->socks_request);
+ socks = conn->socks_request;
+
+ log_debug(LD_APP,"entered.");
+
+ sockshere = fetch_from_buf_socks(base_conn->inbuf, socks,
+ options->TestSocks, options->SafeSocks);
+
+ if (socks->replylen) {
+ had_reply = 1;
+ connection_buf_add((const char*)socks->reply, socks->replylen,
+ base_conn);
+ socks->replylen = 0;
+ if (sockshere == -1) {
+ /* An invalid request just got a reply, no additional
+ * one is necessary. */
+ socks->has_finished = 1;
+ }
+ }
+
+ if (sockshere == 0) {
+ log_debug(LD_APP,"socks handshake not all here yet.");
+ return 0;
+ } else if (sockshere == -1) {
+ if (!had_reply) {
+ log_warn(LD_APP,"Fetching socks handshake failed. Closing.");
+ connection_ap_handshake_socks_reply(conn, NULL, 0,
+ END_STREAM_REASON_SOCKSPROTOCOL);
+ }
+ connection_mark_unattached_ap(conn,
+ END_STREAM_REASON_SOCKSPROTOCOL |
+ END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED);
+ return -1;
+ } /* else socks handshake is done, continue processing */
+
+ if (SOCKS_COMMAND_IS_CONNECT(socks->command))
+ control_event_stream_status(conn, STREAM_EVENT_NEW, 0);
+ else
+ control_event_stream_status(conn, STREAM_EVENT_NEW_RESOLVE, 0);
+
+ return connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL);
+}
+
+/** connection_init_accepted_conn() found a new trans AP conn.
+ * Get the original destination and send it to
+ * connection_ap_handshake_rewrite_and_attach().
+ *
+ * Return -1 if an unexpected error with conn (and it should be marked
+ * for close), else return 0.
+ */
+int
+connection_ap_process_transparent(entry_connection_t *conn)
+{
+ socks_request_t *socks;
+
+ tor_assert(conn);
+ tor_assert(conn->socks_request);
+ socks = conn->socks_request;
+
+ /* pretend that a socks handshake completed so we don't try to
+ * send a socks reply down a transparent conn */
+ socks->command = SOCKS_COMMAND_CONNECT;
+ socks->has_finished = 1;
+
+ log_debug(LD_APP,"entered.");
+
+ if (connection_ap_get_original_destination(conn, socks) < 0) {
+ log_warn(LD_APP,"Fetching original destination failed. Closing.");
+ connection_mark_unattached_ap(conn,
+ END_STREAM_REASON_CANT_FETCH_ORIG_DEST);
+ return -1;
+ }
+ /* we have the original destination */
+
+ control_event_stream_status(conn, STREAM_EVENT_NEW, 0);
+
+ return connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL);
+}
+
+/** connection_edge_process_inbuf() found a conn in state natd_wait. See if
+ * conn-\>inbuf has the right bytes to proceed. See FreeBSD's libalias(3) and
+ * ProxyEncodeTcpStream() in src/lib/libalias/alias_proxy.c for the encoding
+ * form of the original destination.
+ *
+ * If the original destination is complete, send it to
+ * connection_ap_handshake_rewrite_and_attach().
+ *
+ * Return -1 if an unexpected error with conn (and it should be marked
+ * for close), else return 0.
+ */
+static int
+connection_ap_process_natd(entry_connection_t *conn)
+{
+ char tmp_buf[36], *tbuf, *daddr;
+ size_t tlen = 30;
+ int err, port_ok;
+ socks_request_t *socks;
+
+ tor_assert(conn);
+ tor_assert(ENTRY_TO_CONN(conn)->state == AP_CONN_STATE_NATD_WAIT);
+ tor_assert(conn->socks_request);
+ socks = conn->socks_request;
+
+ log_debug(LD_APP,"entered.");
+
+ /* look for LF-terminated "[DEST ip_addr port]"
+ * where ip_addr is a dotted-quad and port is in string form */
+ err = connection_buf_get_line(ENTRY_TO_CONN(conn), tmp_buf, &tlen);
+ if (err == 0)
+ return 0;
+ if (err < 0) {
+ log_warn(LD_APP,"NATD handshake failed (DEST too long). Closing");
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST);
+ return -1;
+ }
+
+ if (strcmpstart(tmp_buf, "[DEST ")) {
+ log_warn(LD_APP,"NATD handshake was ill-formed; closing. The client "
+ "said: %s",
+ escaped(tmp_buf));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST);
+ return -1;
+ }
+
+ daddr = tbuf = &tmp_buf[0] + 6; /* after end of "[DEST " */
+ if (!(tbuf = strchr(tbuf, ' '))) {
+ log_warn(LD_APP,"NATD handshake was ill-formed; closing. The client "
+ "said: %s",
+ escaped(tmp_buf));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST);
+ return -1;
+ }
+ *tbuf++ = '\0';
+
+ /* pretend that a socks handshake completed so we don't try to
+ * send a socks reply down a natd conn */
+ strlcpy(socks->address, daddr, sizeof(socks->address));
+ socks->port = (uint16_t)
+ tor_parse_long(tbuf, 10, 1, 65535, &port_ok, &daddr);
+ if (!port_ok) {
+ log_warn(LD_APP,"NATD handshake failed; port %s is ill-formed or out "
+ "of range.", escaped(tbuf));
+ connection_mark_unattached_ap(conn, END_STREAM_REASON_INVALID_NATD_DEST);
+ return -1;
+ }
+
+ socks->command = SOCKS_COMMAND_CONNECT;
+ socks->has_finished = 1;
+
+ control_event_stream_status(conn, STREAM_EVENT_NEW, 0);
+
+ ENTRY_TO_CONN(conn)->state = AP_CONN_STATE_CIRCUIT_WAIT;
+
+ return connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL);
+}
+
+/** Called on an HTTP CONNECT entry connection when some bytes have arrived,
+ * but we have not yet received a full HTTP CONNECT request. Try to parse an
+ * HTTP CONNECT request from the connection's inbuf. On success, set up the
+ * connection's socks_request field and try to attach the connection. On
+ * failure, send an HTTP reply, and mark the connection.
+ */
+STATIC int
+connection_ap_process_http_connect(entry_connection_t *conn)
+{
+ if (BUG(ENTRY_TO_CONN(conn)->state != AP_CONN_STATE_HTTP_CONNECT_WAIT))
+ return -1;
+
+ char *headers = NULL, *body = NULL;
+ char *command = NULL, *addrport = NULL;
+ char *addr = NULL;
+ size_t bodylen = 0;
+
+ const char *errmsg = NULL;
+ int rv = 0;
+
+ const int http_status =
+ fetch_from_buf_http(ENTRY_TO_CONN(conn)->inbuf, &headers, 8192,
+ &body, &bodylen, 1024, 0);
+ if (http_status < 0) {
+ /* Bad http status */
+ errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n";
+ goto err;
+ } else if (http_status == 0) {
+ /* no HTTP request yet. */
+ goto done;
+ }
+
+ const int cmd_status = parse_http_command(headers, &command, &addrport);
+ if (cmd_status < 0) {
+ errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n";
+ goto err;
+ }
+ tor_assert(command);
+ tor_assert(addrport);
+ if (strcasecmp(command, "connect")) {
+ errmsg = "HTTP/1.0 405 Method Not Allowed\r\n\r\n";
+ goto err;
+ }
+
+ tor_assert(conn->socks_request);
+ socks_request_t *socks = conn->socks_request;
+ uint16_t port;
+ if (tor_addr_port_split(LOG_WARN, addrport, &addr, &port) < 0) {
+ errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n";
+ goto err;
+ }
+ if (strlen(addr) >= MAX_SOCKS_ADDR_LEN) {
+ errmsg = "HTTP/1.0 414 Request-URI Too Long\r\n\r\n";
+ goto err;
+ }
+
+ /* Abuse the 'username' and 'password' fields here. They are already an
+ * abuse. */
+ {
+ char *authorization = http_get_header(headers, "Proxy-Authorization: ");
+ if (authorization) {
+ socks->username = authorization; // steal reference
+ socks->usernamelen = strlen(authorization);
+ }
+ char *isolation = http_get_header(headers, "X-Tor-Stream-Isolation: ");
+ if (isolation) {
+ socks->password = isolation; // steal reference
+ socks->passwordlen = strlen(isolation);
+ }
+ }
+
+ socks->command = SOCKS_COMMAND_CONNECT;
+ socks->listener_type = CONN_TYPE_AP_HTTP_CONNECT_LISTENER;
+ strlcpy(socks->address, addr, sizeof(socks->address));
+ socks->port = port;
+
+ control_event_stream_status(conn, STREAM_EVENT_NEW, 0);
+
+ rv = connection_ap_rewrite_and_attach_if_allowed(conn, NULL, NULL);
+
+ // XXXX send a "100 Continue" message?
+
+ goto done;
+
+ err:
+ if (BUG(errmsg == NULL))
+ errmsg = "HTTP/1.0 400 Bad Request\r\n\r\n";
+ log_info(LD_EDGE, "HTTP tunnel error: saying %s", escaped(errmsg));
+ connection_buf_add(errmsg, strlen(errmsg), ENTRY_TO_CONN(conn));
+ /* Mark it as "has_finished" so that we don't try to send an extra socks
+ * reply. */
+ conn->socks_request->has_finished = 1;
+ connection_mark_unattached_ap(conn,
+ END_STREAM_REASON_HTTPPROTOCOL|
+ END_STREAM_REASON_FLAG_ALREADY_SOCKS_REPLIED);
+
+ done:
+ tor_free(headers);
+ tor_free(body);
+ tor_free(command);
+ tor_free(addrport);
+ tor_free(addr);
+ return rv;
+}
+
+/** Iterate over the two bytes of stream_id until we get one that is not
+ * already in use; return it. Return 0 if can't get a unique stream_id.
+ */
+streamid_t
+get_unique_stream_id_by_circ(origin_circuit_t *circ)
+{
+ edge_connection_t *tmpconn;
+ streamid_t test_stream_id;
+ uint32_t attempts=0;
+
+ again:
+ test_stream_id = circ->next_stream_id++;
+ if (++attempts > 1<<16) {
+ /* Make sure we don't loop forever if all stream_id's are used. */
+ log_warn(LD_APP,"No unused stream IDs. Failing.");
+ return 0;
+ }
+ if (test_stream_id == 0)
+ goto again;
+ for (tmpconn = circ->p_streams; tmpconn; tmpconn=tmpconn->next_stream)
+ if (tmpconn->stream_id == test_stream_id)
+ goto again;
+
+ if (connection_half_edge_find_stream_id(circ->half_streams,
+ test_stream_id))
+ goto again;
+
+ return test_stream_id;
+}
+
+/** Return true iff <b>conn</b> is linked to a circuit and configured to use
+ * an exit that supports optimistic data. */
+static int
+connection_ap_supports_optimistic_data(const entry_connection_t *conn)
+{
+ const edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(conn);
+ /* We can only send optimistic data if we're connected to an open
+ general circuit. */
+ if (edge_conn->on_circuit == NULL ||
+ edge_conn->on_circuit->state != CIRCUIT_STATE_OPEN ||
+ (edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_GENERAL &&
+ edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_HSDIR_GET &&
+ edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_S_HSDIR_POST &&
+ edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_REND_JOINED))
+ return 0;
+
+ return conn->may_use_optimistic_data;
+}
+
+/** Return a bitmask of BEGIN_FLAG_* flags that we should transmit in the
+ * RELAY_BEGIN cell for <b>ap_conn</b>. */
+static uint32_t
+connection_ap_get_begincell_flags(entry_connection_t *ap_conn)
+{
+ edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(ap_conn);
+ const node_t *exitnode = NULL;
+ const crypt_path_t *cpath_layer = edge_conn->cpath_layer;
+ uint32_t flags = 0;
+
+ /* No flags for begindir */
+ if (ap_conn->use_begindir)
+ return 0;
+
+ /* No flags for hidden services. */
+ if (edge_conn->on_circuit->purpose != CIRCUIT_PURPOSE_C_GENERAL)
+ return 0;
+
+ /* If only IPv4 is supported, no flags */
+ if (ap_conn->entry_cfg.ipv4_traffic && !ap_conn->entry_cfg.ipv6_traffic)
+ return 0;
+
+ if (! cpath_layer ||
+ ! cpath_layer->extend_info)
+ return 0;
+
+ if (!ap_conn->entry_cfg.ipv4_traffic)
+ flags |= BEGIN_FLAG_IPV4_NOT_OK;
+
+ exitnode = node_get_by_id(cpath_layer->extend_info->identity_digest);
+
+ if (ap_conn->entry_cfg.ipv6_traffic && exitnode) {
+ tor_addr_t a;
+ tor_addr_make_null(&a, AF_INET6);
+ if (compare_tor_addr_to_node_policy(&a, ap_conn->socks_request->port,
+ exitnode)
+ != ADDR_POLICY_REJECTED) {
+ /* Only say "IPv6 OK" if the exit node supports IPv6. Otherwise there's
+ * no point. */
+ flags |= BEGIN_FLAG_IPV6_OK;
+ }
+ }
+
+ if (flags == BEGIN_FLAG_IPV6_OK) {
+ /* When IPv4 and IPv6 are both allowed, consider whether to say we
+ * prefer IPv6. Otherwise there's no point in declaring a preference */
+ if (ap_conn->entry_cfg.prefer_ipv6)
+ flags |= BEGIN_FLAG_IPV6_PREFERRED;
+ }
+
+ if (flags == BEGIN_FLAG_IPV4_NOT_OK) {
+ log_warn(LD_EDGE, "I'm about to ask a node for a connection that I "
+ "am telling it to fulfil with neither IPv4 nor IPv6. That's "
+ "not going to work. Did you perhaps ask for an IPv6 address "
+ "on an IPv4Only port, or vice versa?");
+ }
+
+ return flags;
+}
+
+/** Write a relay begin cell, using destaddr and destport from ap_conn's
+ * socks_request field, and send it down circ.
+ *
+ * If ap_conn is broken, mark it for close and return -1. Else return 0.
+ */
+MOCK_IMPL(int,
+connection_ap_handshake_send_begin,(entry_connection_t *ap_conn))
+{
+ char payload[CELL_PAYLOAD_SIZE];
+ int payload_len;
+ int begin_type;
+ const or_options_t *options = get_options();
+ origin_circuit_t *circ;
+ edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(ap_conn);
+ connection_t *base_conn = TO_CONN(edge_conn);
+ tor_assert(edge_conn->on_circuit);
+ circ = TO_ORIGIN_CIRCUIT(edge_conn->on_circuit);
+
+ tor_assert(base_conn->type == CONN_TYPE_AP);
+ tor_assert(base_conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
+ tor_assert(ap_conn->socks_request);
+ tor_assert(SOCKS_COMMAND_IS_CONNECT(ap_conn->socks_request->command));
+
+ edge_conn->stream_id = get_unique_stream_id_by_circ(circ);
+ if (edge_conn->stream_id==0) {
+ /* XXXX+ Instead of closing this stream, we should make it get
+ * retried on another circuit. */
+ connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
+
+ /* Mark this circuit "unusable for new streams". */
+ mark_circuit_unusable_for_new_conns(circ);
+ return -1;
+ }
+
+ /* Set up begin cell flags. */
+ edge_conn->begincell_flags = connection_ap_get_begincell_flags(ap_conn);
+
+ tor_snprintf(payload,RELAY_PAYLOAD_SIZE, "%s:%d",
+ (circ->base_.purpose == CIRCUIT_PURPOSE_C_GENERAL) ?
+ ap_conn->socks_request->address : "",
+ ap_conn->socks_request->port);
+ payload_len = (int)strlen(payload)+1;
+ if (payload_len <= RELAY_PAYLOAD_SIZE - 4 && edge_conn->begincell_flags) {
+ set_uint32(payload + payload_len, htonl(edge_conn->begincell_flags));
+ payload_len += 4;
+ }
+
+ log_info(LD_APP,
+ "Sending relay cell %d on circ %u to begin stream %d.",
+ (int)ap_conn->use_begindir,
+ (unsigned)circ->base_.n_circ_id,
+ edge_conn->stream_id);
+
+ begin_type = ap_conn->use_begindir ?
+ RELAY_COMMAND_BEGIN_DIR : RELAY_COMMAND_BEGIN;
+
+ /* Check that circuits are anonymised, based on their type. */
+ if (begin_type == RELAY_COMMAND_BEGIN) {
+ /* This connection is a standard OR connection.
+ * Make sure its path length is anonymous, or that we're in a
+ * non-anonymous mode. */
+ assert_circ_anonymity_ok(circ, options);
+ } else if (begin_type == RELAY_COMMAND_BEGIN_DIR) {
+ /* This connection is a begindir directory connection.
+ * Look at the linked directory connection to access the directory purpose.
+ * If a BEGINDIR connection is ever not linked, that's a bug. */
+ if (BUG(!base_conn->linked)) {
+ return -1;
+ }
+ connection_t *linked_dir_conn_base = base_conn->linked_conn;
+ /* If the linked connection has been unlinked by other code, we can't send
+ * a begin cell on it. */
+ if (!linked_dir_conn_base) {
+ return -1;
+ }
+ /* Sensitive directory connections must have an anonymous path length.
+ * Otherwise, directory connections are typically one-hop.
+ * This matches the earlier check for directory connection path anonymity
+ * in directory_initiate_request(). */
+ if (purpose_needs_anonymity(linked_dir_conn_base->purpose,
+ TO_DIR_CONN(linked_dir_conn_base)->router_purpose,
+ TO_DIR_CONN(linked_dir_conn_base)->requested_resource)) {
+ assert_circ_anonymity_ok(circ, options);
+ }
+ } else {
+ /* This code was written for the two connection types BEGIN and BEGIN_DIR
+ */
+ tor_assert_unreached();
+ }
+
+ if (connection_edge_send_command(edge_conn, begin_type,
+ begin_type == RELAY_COMMAND_BEGIN ? payload : NULL,
+ begin_type == RELAY_COMMAND_BEGIN ? payload_len : 0) < 0)
+ return -1; /* circuit is closed, don't continue */
+
+ edge_conn->package_window = STREAMWINDOW_START;
+ edge_conn->deliver_window = STREAMWINDOW_START;
+ base_conn->state = AP_CONN_STATE_CONNECT_WAIT;
+ log_info(LD_APP,"Address/port sent, ap socket "TOR_SOCKET_T_FORMAT
+ ", n_circ_id %u",
+ base_conn->s, (unsigned)circ->base_.n_circ_id);
+ control_event_stream_status(ap_conn, STREAM_EVENT_SENT_CONNECT, 0);
+
+ /* If there's queued-up data, send it now */
+ if ((connection_get_inbuf_len(base_conn) ||
+ ap_conn->sending_optimistic_data) &&
+ connection_ap_supports_optimistic_data(ap_conn)) {
+ log_info(LD_APP, "Sending up to %ld + %ld bytes of queued-up data",
+ (long)connection_get_inbuf_len(base_conn),
+ ap_conn->sending_optimistic_data ?
+ (long)buf_datalen(ap_conn->sending_optimistic_data) : 0);
+ if (connection_edge_package_raw_inbuf(edge_conn, 1, NULL) < 0) {
+ connection_mark_for_close(base_conn);
+ }
+ }
+
+ return 0;
+}
+
+/** Write a relay resolve cell, using destaddr and destport from ap_conn's
+ * socks_request field, and send it down circ.
+ *
+ * If ap_conn is broken, mark it for close and return -1. Else return 0.
+ */
+int
+connection_ap_handshake_send_resolve(entry_connection_t *ap_conn)
+{
+ int payload_len, command;
+ const char *string_addr;
+ char inaddr_buf[REVERSE_LOOKUP_NAME_BUF_LEN];
+ origin_circuit_t *circ;
+ edge_connection_t *edge_conn = ENTRY_TO_EDGE_CONN(ap_conn);
+ connection_t *base_conn = TO_CONN(edge_conn);
+ tor_assert(edge_conn->on_circuit);
+ circ = TO_ORIGIN_CIRCUIT(edge_conn->on_circuit);
+
+ tor_assert(base_conn->type == CONN_TYPE_AP);
+ tor_assert(base_conn->state == AP_CONN_STATE_CIRCUIT_WAIT);
+ tor_assert(ap_conn->socks_request);
+ tor_assert(circ->base_.purpose == CIRCUIT_PURPOSE_C_GENERAL);
+
+ command = ap_conn->socks_request->command;
+ tor_assert(SOCKS_COMMAND_IS_RESOLVE(command));
+
+ edge_conn->stream_id = get_unique_stream_id_by_circ(circ);
+ if (edge_conn->stream_id==0) {
+ /* XXXX+ Instead of closing this stream, we should make it get
+ * retried on another circuit. */
+ connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
+
+ /* Mark this circuit "unusable for new streams". */
+ mark_circuit_unusable_for_new_conns(circ);
+ return -1;
+ }
+
+ if (command == SOCKS_COMMAND_RESOLVE) {
+ string_addr = ap_conn->socks_request->address;
+ payload_len = (int)strlen(string_addr)+1;
+ } else {
+ /* command == SOCKS_COMMAND_RESOLVE_PTR */
+ const char *a = ap_conn->socks_request->address;
+ tor_addr_t addr;
+ int r;
+
+ /* We're doing a reverse lookup. The input could be an IP address, or
+ * could be an .in-addr.arpa or .ip6.arpa address */
+ r = tor_addr_parse_PTR_name(&addr, a, AF_UNSPEC, 1);
+ if (r <= 0) {
+ log_warn(LD_APP, "Rejecting ill-formed reverse lookup of %s",
+ safe_str_client(a));
+ connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
+ return -1;
+ }
+
+ r = tor_addr_to_PTR_name(inaddr_buf, sizeof(inaddr_buf), &addr);
+ if (r < 0) {
+ log_warn(LD_BUG, "Couldn't generate reverse lookup hostname of %s",
+ safe_str_client(a));
+ connection_mark_unattached_ap(ap_conn, END_STREAM_REASON_INTERNAL);
+ return -1;
+ }
+
+ string_addr = inaddr_buf;
+ payload_len = (int)strlen(inaddr_buf)+1;
+ tor_assert(payload_len <= (int)sizeof(inaddr_buf));
+ }
+
+ log_debug(LD_APP,
+ "Sending relay cell to begin stream %d.", edge_conn->stream_id);
+
+ if (connection_edge_send_command(edge_conn,
+ RELAY_COMMAND_RESOLVE,
+ string_addr, payload_len) < 0)
+ return -1; /* circuit is closed, don't continue */
+
+ if (!base_conn->address) {
+ /* This might be unnecessary. XXXX */
+ base_conn->address = tor_addr_to_str_dup(&base_conn->addr);
+ }
+ base_conn->state = AP_CONN_STATE_RESOLVE_WAIT;
+ log_info(LD_APP,"Address sent for resolve, ap socket "TOR_SOCKET_T_FORMAT
+ ", n_circ_id %u",
+ base_conn->s, (unsigned)circ->base_.n_circ_id);
+ control_event_stream_status(ap_conn, STREAM_EVENT_SENT_RESOLVE, 0);
+ return 0;
+}
+
+/** Make an AP connection_t linked to the connection_t <b>partner</b>. make a
+ * new linked connection pair, and attach one side to the conn, connection_add
+ * it, initialize it to circuit_wait, and call
+ * connection_ap_handshake_attach_circuit(conn) on it.
+ *
+ * Return the newly created end of the linked connection pair, or -1 if error.
+ */
+entry_connection_t *
+connection_ap_make_link(connection_t *partner,
+ char *address, uint16_t port,
+ const char *digest,
+ int session_group, int isolation_flags,
+ int use_begindir, int want_onehop)
+{
+ entry_connection_t *conn;
+ connection_t *base_conn;
+
+ log_info(LD_APP,"Making internal %s tunnel to %s:%d ...",
+ want_onehop ? "direct" : "anonymized",
+ safe_str_client(address), port);
+
+ conn = entry_connection_new(CONN_TYPE_AP, tor_addr_family(&partner->addr));
+ base_conn = ENTRY_TO_CONN(conn);
+ base_conn->linked = 1; /* so that we can add it safely below. */
+
+ /* populate conn->socks_request */
+
+ /* leave version at zero, so the socks_reply is empty */
+ conn->socks_request->socks_version = 0;
+ conn->socks_request->has_finished = 0; /* waiting for 'connected' */
+ strlcpy(conn->socks_request->address, address,
+ sizeof(conn->socks_request->address));
+ conn->socks_request->port = port;
+ conn->socks_request->command = SOCKS_COMMAND_CONNECT;
+ conn->want_onehop = want_onehop;
+ conn->use_begindir = use_begindir;
+ if (use_begindir) {
+ conn->chosen_exit_name = tor_malloc(HEX_DIGEST_LEN+2);
+ conn->chosen_exit_name[0] = '$';
+ tor_assert(digest);
+ base16_encode(conn->chosen_exit_name+1,HEX_DIGEST_LEN+1,
+ digest, DIGEST_LEN);
+ }
+
+ /* Populate isolation fields. */
+ conn->socks_request->listener_type = CONN_TYPE_DIR_LISTENER;
+ conn->original_dest_address = tor_strdup(address);
+ conn->entry_cfg.session_group = session_group;
+ conn->entry_cfg.isolation_flags = isolation_flags;
+
+ base_conn->address = tor_strdup("(Tor_internal)");
+ tor_addr_make_unspec(&base_conn->addr);
+ base_conn->port = 0;
+
+ connection_link_connections(partner, base_conn);
+
+ if (connection_add(base_conn) < 0) { /* no space, forget it */
+ connection_free(base_conn);
+ return NULL;
+ }
+
+ base_conn->state = AP_CONN_STATE_CIRCUIT_WAIT;
+
+ control_event_stream_status(conn, STREAM_EVENT_NEW, 0);
+
+ /* attaching to a dirty circuit is fine */
+ connection_ap_mark_as_pending_circuit(conn);
+ log_info(LD_APP,"... application connection created and linked.");
+ return conn;
+}
+
+/** Notify any interested controller connections about a new hostname resolve
+ * or resolve error. Takes the same arguments as does
+ * connection_ap_handshake_socks_resolved(). */
+static void
+tell_controller_about_resolved_result(entry_connection_t *conn,
+ int answer_type,
+ size_t answer_len,
+ const char *answer,
+ int ttl,
+ time_t expires)
+{
+ expires = time(NULL) + ttl;
+ if (answer_type == RESOLVED_TYPE_IPV4 && answer_len >= 4) {
+ char *cp = tor_dup_ip(ntohl(get_uint32(answer)));
+ control_event_address_mapped(conn->socks_request->address,
+ cp, expires, NULL, 0);
+ tor_free(cp);
+ } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) {
+ char *cp = tor_strndup(answer, answer_len);
+ control_event_address_mapped(conn->socks_request->address,
+ cp, expires, NULL, 0);
+ tor_free(cp);
+ } else {
+ control_event_address_mapped(conn->socks_request->address,
+ "<error>", time(NULL)+ttl,
+ "error=yes", 0);
+ }
+}
+
+/**
+ * As connection_ap_handshake_socks_resolved, but take a tor_addr_t to send
+ * as the answer.
+ */
+void
+connection_ap_handshake_socks_resolved_addr(entry_connection_t *conn,
+ const tor_addr_t *answer,
+ int ttl,
+ time_t expires)
+{
+ if (tor_addr_family(answer) == AF_INET) {
+ uint32_t a = tor_addr_to_ipv4n(answer); /* network order */
+ connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_IPV4,4,
+ (uint8_t*)&a,
+ ttl, expires);
+ } else if (tor_addr_family(answer) == AF_INET6) {
+ const uint8_t *a = tor_addr_to_in6_addr8(answer);
+ connection_ap_handshake_socks_resolved(conn,RESOLVED_TYPE_IPV6,16,
+ a,
+ ttl, expires);
+ } else {
+ log_warn(LD_BUG, "Got called with address of unexpected family %d",
+ tor_addr_family(answer));
+ connection_ap_handshake_socks_resolved(conn,
+ RESOLVED_TYPE_ERROR,0,NULL,-1,-1);
+ }
+}
+
+/** Send an answer to an AP connection that has requested a DNS lookup via
+ * SOCKS. The type should be one of RESOLVED_TYPE_(IPV4|IPV6|HOSTNAME) or -1
+ * for unreachable; the answer should be in the format specified in the socks
+ * extensions document. <b>ttl</b> is the ttl for the answer, or -1 on
+ * certain errors or for values that didn't come via DNS. <b>expires</b> is
+ * a time when the answer expires, or -1 or TIME_MAX if there's a good TTL.
+ **/
+/* XXXX the use of the ttl and expires fields is nutty. Let's make this
+ * interface and those that use it less ugly. */
+MOCK_IMPL(void,
+connection_ap_handshake_socks_resolved,(entry_connection_t *conn,
+ int answer_type,
+ size_t answer_len,
+ const uint8_t *answer,
+ int ttl,
+ time_t expires))
+{
+ char buf[384];
+ size_t replylen;
+
+ if (ttl >= 0) {
+ if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) {
+ tor_addr_t a;
+ tor_addr_from_ipv4n(&a, get_uint32(answer));
+ if (! tor_addr_is_null(&a)) {
+ client_dns_set_addressmap(conn,
+ conn->socks_request->address, &a,
+ conn->chosen_exit_name, ttl);
+ }
+ } else if (answer_type == RESOLVED_TYPE_IPV6 && answer_len == 16) {
+ tor_addr_t a;
+ tor_addr_from_ipv6_bytes(&a, (char*)answer);
+ if (! tor_addr_is_null(&a)) {
+ client_dns_set_addressmap(conn,
+ conn->socks_request->address, &a,
+ conn->chosen_exit_name, ttl);
+ }
+ } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) {
+ char *cp = tor_strndup((char*)answer, answer_len);
+ client_dns_set_reverse_addressmap(conn,
+ conn->socks_request->address,
+ cp,
+ conn->chosen_exit_name, ttl);
+ tor_free(cp);
+ }
+ }
+
+ if (ENTRY_TO_EDGE_CONN(conn)->is_dns_request) {
+ if (conn->dns_server_request) {
+ /* We had a request on our DNS port: answer it. */
+ dnsserv_resolved(conn, answer_type, answer_len, (char*)answer, ttl);
+ conn->socks_request->has_finished = 1;
+ return;
+ } else {
+ /* This must be a request from the controller. Since answers to those
+ * requests are not cached, they do not generate an ADDRMAP event on
+ * their own. */
+ tell_controller_about_resolved_result(conn, answer_type, answer_len,
+ (char*)answer, ttl, expires);
+ conn->socks_request->has_finished = 1;
+ return;
+ }
+ /* We shouldn't need to free conn here; it gets marked by the caller. */
+ }
+
+ if (conn->socks_request->socks_version == 4) {
+ buf[0] = 0x00; /* version */
+ if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) {
+ buf[1] = SOCKS4_GRANTED;
+ set_uint16(buf+2, 0);
+ memcpy(buf+4, answer, 4); /* address */
+ replylen = SOCKS4_NETWORK_LEN;
+ } else { /* "error" */
+ buf[1] = SOCKS4_REJECT;
+ memset(buf+2, 0, 6);
+ replylen = SOCKS4_NETWORK_LEN;
+ }
+ } else if (conn->socks_request->socks_version == 5) {
+ /* SOCKS5 */
+ buf[0] = 0x05; /* version */
+ if (answer_type == RESOLVED_TYPE_IPV4 && answer_len == 4) {
+ buf[1] = SOCKS5_SUCCEEDED;
+ buf[2] = 0; /* reserved */
+ buf[3] = 0x01; /* IPv4 address type */
+ memcpy(buf+4, answer, 4); /* address */
+ set_uint16(buf+8, 0); /* port == 0. */
+ replylen = 10;
+ } else if (answer_type == RESOLVED_TYPE_IPV6 && answer_len == 16) {
+ buf[1] = SOCKS5_SUCCEEDED;
+ buf[2] = 0; /* reserved */
+ buf[3] = 0x04; /* IPv6 address type */
+ memcpy(buf+4, answer, 16); /* address */
+ set_uint16(buf+20, 0); /* port == 0. */
+ replylen = 22;
+ } else if (answer_type == RESOLVED_TYPE_HOSTNAME && answer_len < 256) {
+ buf[1] = SOCKS5_SUCCEEDED;
+ buf[2] = 0; /* reserved */
+ buf[3] = 0x03; /* Domainname address type */
+ buf[4] = (char)answer_len;
+ memcpy(buf+5, answer, answer_len); /* address */
+ set_uint16(buf+5+answer_len, 0); /* port == 0. */
+ replylen = 5+answer_len+2;
+ } else {
+ buf[1] = SOCKS5_HOST_UNREACHABLE;
+ memset(buf+2, 0, 8);
+ replylen = 10;
+ }
+ } else {
+ /* no socks version info; don't send anything back */
+ return;
+ }
+ connection_ap_handshake_socks_reply(conn, buf, replylen,
+ (answer_type == RESOLVED_TYPE_IPV4 ||
+ answer_type == RESOLVED_TYPE_IPV6 ||
+ answer_type == RESOLVED_TYPE_HOSTNAME) ?
+ 0 : END_STREAM_REASON_RESOLVEFAILED);
+}
+
+/** Send a socks reply to stream <b>conn</b>, using the appropriate
+ * socks version, etc, and mark <b>conn</b> as completed with SOCKS
+ * handshaking.
+ *
+ * If <b>reply</b> is defined, then write <b>replylen</b> bytes of it to conn
+ * and return, else reply based on <b>endreason</b> (one of
+ * END_STREAM_REASON_*). If <b>reply</b> is undefined, <b>endreason</b> can't
+ * be 0 or REASON_DONE. Send endreason to the controller, if appropriate.
+ */
+void
+connection_ap_handshake_socks_reply(entry_connection_t *conn, char *reply,
+ size_t replylen, int endreason)
+{
+ char buf[256];
+ socks5_reply_status_t status =
+ stream_end_reason_to_socks5_response(endreason);
+
+ tor_assert(conn->socks_request); /* make sure it's an AP stream */
+
+ if (!SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command)) {
+ control_event_stream_status(conn, status==SOCKS5_SUCCEEDED ?
+ STREAM_EVENT_SUCCEEDED : STREAM_EVENT_FAILED,
+ endreason);
+ }
+
+ /* Flag this stream's circuit as having completed a stream successfully
+ * (for path bias) */
+ if (status == SOCKS5_SUCCEEDED ||
+ endreason == END_STREAM_REASON_RESOLVEFAILED ||
+ endreason == END_STREAM_REASON_CONNECTREFUSED ||
+ endreason == END_STREAM_REASON_CONNRESET ||
+ endreason == END_STREAM_REASON_NOROUTE ||
+ endreason == END_STREAM_REASON_RESOURCELIMIT) {
+ if (!conn->edge_.on_circuit ||
+ !CIRCUIT_IS_ORIGIN(conn->edge_.on_circuit)) {
+ if (endreason != END_STREAM_REASON_RESOLVEFAILED) {
+ log_info(LD_BUG,
+ "No origin circuit for successful SOCKS stream %"PRIu64
+ ". Reason: %d",
+ (ENTRY_TO_CONN(conn)->global_identifier),
+ endreason);
+ }
+ /*
+ * Else DNS remaps and failed hidden service lookups can send us
+ * here with END_STREAM_REASON_RESOLVEFAILED; ignore it
+ *
+ * Perhaps we could make the test more precise; we can tell hidden
+ * services by conn->edge_.renddata != NULL; anything analogous for
+ * the DNS remap case?
+ */
+ } else {
+ // XXX: Hrmm. It looks like optimistic data can't go through this
+ // codepath, but someone should probably test it and make sure.
+ // We don't want to mark optimistically opened streams as successful.
+ pathbias_mark_use_success(TO_ORIGIN_CIRCUIT(conn->edge_.on_circuit));
+ }
+ }
+
+ if (conn->socks_request->has_finished) {
+ log_warn(LD_BUG, "(Harmless.) duplicate calls to "
+ "connection_ap_handshake_socks_reply.");
+ return;
+ }
+ if (replylen) { /* we already have a reply in mind */
+ connection_buf_add(reply, replylen, ENTRY_TO_CONN(conn));
+ conn->socks_request->has_finished = 1;
+ return;
+ }
+ if (conn->socks_request->listener_type ==
+ CONN_TYPE_AP_HTTP_CONNECT_LISTENER) {
+ const char *response = end_reason_to_http_connect_response_line(endreason);
+ if (!response) {
+ response = "HTTP/1.0 400 Bad Request\r\n\r\n";
+ }
+ connection_buf_add(response, strlen(response), ENTRY_TO_CONN(conn));
+ } else if (conn->socks_request->socks_version == 4) {
+ memset(buf,0,SOCKS4_NETWORK_LEN);
+ buf[1] = (status==SOCKS5_SUCCEEDED ? SOCKS4_GRANTED : SOCKS4_REJECT);
+ /* leave version, destport, destip zero */
+ connection_buf_add(buf, SOCKS4_NETWORK_LEN, ENTRY_TO_CONN(conn));
+ } else if (conn->socks_request->socks_version == 5) {
+ size_t buf_len;
+ memset(buf,0,sizeof(buf));
+ if (tor_addr_family(&conn->edge_.base_.addr) == AF_INET) {
+ buf[0] = 5; /* version 5 */
+ buf[1] = (char)status;
+ buf[2] = 0;
+ buf[3] = 1; /* ipv4 addr */
+ /* 4 bytes for the header, 2 bytes for the port, 4 for the address. */
+ buf_len = 10;
+ } else { /* AF_INET6. */
+ buf[0] = 5; /* version 5 */
+ buf[1] = (char)status;
+ buf[2] = 0;
+ buf[3] = 4; /* ipv6 addr */
+ /* 4 bytes for the header, 2 bytes for the port, 16 for the address. */
+ buf_len = 22;
+ }
+ connection_buf_add(buf,buf_len,ENTRY_TO_CONN(conn));
+ }
+ /* If socks_version isn't 4 or 5, don't send anything.
+ * This can happen in the case of AP bridges. */
+ conn->socks_request->has_finished = 1;
+ return;
+}
+
+/** Read a RELAY_BEGIN or RELAY_BEGIN_DIR cell from <b>cell</b>, decode it, and
+ * place the result in <b>bcell</b>. On success return 0; on failure return
+ * <0 and set *<b>end_reason_out</b> to the end reason we should send back to
+ * the client.
+ *
+ * Return -1 in the case where we want to send a RELAY_END cell, and < -1 when
+ * we don't.
+ **/
+STATIC int
+begin_cell_parse(const cell_t *cell, begin_cell_t *bcell,
+ uint8_t *end_reason_out)
+{
+ relay_header_t rh;
+ const uint8_t *body, *nul;
+
+ memset(bcell, 0, sizeof(*bcell));
+ *end_reason_out = END_STREAM_REASON_MISC;
+
+ relay_header_unpack(&rh, cell->payload);
+ if (rh.length > RELAY_PAYLOAD_SIZE) {
+ return -2; /*XXXX why not TORPROTOCOL? */
+ }
+
+ bcell->stream_id = rh.stream_id;
+
+ if (rh.command == RELAY_COMMAND_BEGIN_DIR) {
+ bcell->is_begindir = 1;
+ return 0;
+ } else if (rh.command != RELAY_COMMAND_BEGIN) {
+ log_warn(LD_BUG, "Got an unexpected command %d", (int)rh.command);
+ *end_reason_out = END_STREAM_REASON_INTERNAL;
+ return -1;
+ }
+
+ body = cell->payload + RELAY_HEADER_SIZE;
+ nul = memchr(body, 0, rh.length);
+ if (! nul) {
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
+ "Relay begin cell has no \\0. Closing.");
+ *end_reason_out = END_STREAM_REASON_TORPROTOCOL;
+ return -1;
+ }
+
+ if (tor_addr_port_split(LOG_PROTOCOL_WARN,
+ (char*)(body),
+ &bcell->address,&bcell->port)<0) {
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
+ "Unable to parse addr:port in relay begin cell. Closing.");
+ *end_reason_out = END_STREAM_REASON_TORPROTOCOL;
+ return -1;
+ }
+ if (bcell->port == 0) {
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
+ "Missing port in relay begin cell. Closing.");
+ tor_free(bcell->address);
+ *end_reason_out = END_STREAM_REASON_TORPROTOCOL;
+ return -1;
+ }
+ if (body + rh.length >= nul + 4)
+ bcell->flags = ntohl(get_uint32(nul+1));
+
+ return 0;
+}
+
+/** For the given <b>circ</b> and the edge connection <b>conn</b>, setup the
+ * connection, attach it to the circ and connect it. Return 0 on success
+ * or END_CIRC_AT_ORIGIN if we can't find the requested hidden service port
+ * where the caller should close the circuit. */
+static int
+handle_hs_exit_conn(circuit_t *circ, edge_connection_t *conn)
+{
+ int ret;
+ origin_circuit_t *origin_circ;
+
+ assert_circuit_ok(circ);
+ tor_assert(circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED);
+ tor_assert(conn);
+
+ log_debug(LD_REND, "Connecting the hidden service rendezvous circuit "
+ "to the service destination.");
+
+ origin_circ = TO_ORIGIN_CIRCUIT(circ);
+ conn->base_.address = tor_strdup("(rendezvous)");
+ conn->base_.state = EXIT_CONN_STATE_CONNECTING;
+
+ /* The circuit either has an hs identifier for v3+ or a rend_data for legacy
+ * service. */
+ if (origin_circ->rend_data) {
+ conn->rend_data = rend_data_dup(origin_circ->rend_data);
+ tor_assert(connection_edge_is_rendezvous_stream(conn));
+ ret = rend_service_set_connection_addr_port(conn, origin_circ);
+ } else if (origin_circ->hs_ident) {
+ /* Setup the identifier to be the one for the circuit service. */
+ conn->hs_ident =
+ hs_ident_edge_conn_new(&origin_circ->hs_ident->identity_pk);
+ tor_assert(connection_edge_is_rendezvous_stream(conn));
+ ret = hs_service_set_conn_addr_port(origin_circ, conn);
+ } else {
+ /* We should never get here if the circuit's purpose is rendezvous. */
+ tor_assert_nonfatal_unreached();
+ return -1;
+ }
+ if (ret < 0) {
+ log_info(LD_REND, "Didn't find rendezvous service (addr%s, port %d)",
+ fmt_addr(&TO_CONN(conn)->addr), TO_CONN(conn)->port);
+ /* Send back reason DONE because we want to make hidden service port
+ * scanning harder thus instead of returning that the exit policy
+ * didn't match, which makes it obvious that the port is closed,
+ * return DONE and kill the circuit. That way, a user (malicious or
+ * not) needs one circuit per bad port unless it matches the policy of
+ * the hidden service. */
+ relay_send_end_cell_from_edge(conn->stream_id, circ,
+ END_STREAM_REASON_DONE,
+ origin_circ->cpath->prev);
+ connection_free_(TO_CONN(conn));
+
+ /* Drop the circuit here since it might be someone deliberately
+ * scanning the hidden service ports. Note that this mitigates port
+ * scanning by adding more work on the attacker side to successfully
+ * scan but does not fully solve it. */
+ if (ret < -1) {
+ return END_CIRC_AT_ORIGIN;
+ } else {
+ return 0;
+ }
+ }
+
+ /* Link the circuit and the connection crypt path. */
+ conn->cpath_layer = origin_circ->cpath->prev;
+
+ /* Add it into the linked list of p_streams on this circuit */
+ conn->next_stream = origin_circ->p_streams;
+ origin_circ->p_streams = conn;
+ conn->on_circuit = circ;
+ assert_circuit_ok(circ);
+
+ hs_inc_rdv_stream_counter(origin_circ);
+
+ /* If it's an onion service connection, we might want to include the proxy
+ * protocol header: */
+ if (conn->hs_ident) {
+ hs_circuit_id_protocol_t circuit_id_protocol =
+ hs_service_exports_circuit_id(&conn->hs_ident->identity_pk);
+ export_hs_client_circuit_id(conn, circuit_id_protocol);
+ }
+
+ /* Connect tor to the hidden service destination. */
+ connection_exit_connect(conn);
+
+ /* For path bias: This circuit was used successfully */
+ pathbias_mark_use_success(origin_circ);
+ return 0;
+}
+
+/** A relay 'begin' or 'begin_dir' cell has arrived, and either we are
+ * an exit hop for the circuit, or we are the origin and it is a
+ * rendezvous begin.
+ *
+ * Launch a new exit connection and initialize things appropriately.
+ *
+ * If it's a rendezvous stream, call connection_exit_connect() on
+ * it.
+ *
+ * For general streams, call dns_resolve() on it first, and only call
+ * connection_exit_connect() if the dns answer is already known.
+ *
+ * Note that we don't call connection_add() on the new stream! We wait
+ * for connection_exit_connect() to do that.
+ *
+ * Return -(some circuit end reason) if we want to tear down <b>circ</b>.
+ * Else return 0.
+ */
+int
+connection_exit_begin_conn(cell_t *cell, circuit_t *circ)
+{
+ edge_connection_t *n_stream;
+ relay_header_t rh;
+ char *address = NULL;
+ uint16_t port = 0;
+ or_circuit_t *or_circ = NULL;
+ origin_circuit_t *origin_circ = NULL;
+ crypt_path_t *layer_hint = NULL;
+ const or_options_t *options = get_options();
+ begin_cell_t bcell;
+ int rv;
+ uint8_t end_reason=0;
+
+ assert_circuit_ok(circ);
+ if (!CIRCUIT_IS_ORIGIN(circ)) {
+ or_circ = TO_OR_CIRCUIT(circ);
+ } else {
+ tor_assert(circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED);
+ origin_circ = TO_ORIGIN_CIRCUIT(circ);
+ layer_hint = origin_circ->cpath->prev;
+ }
+
+ relay_header_unpack(&rh, cell->payload);
+ if (rh.length > RELAY_PAYLOAD_SIZE)
+ return -END_CIRC_REASON_TORPROTOCOL;
+
+ if (!server_mode(options) &&
+ circ->purpose != CIRCUIT_PURPOSE_S_REND_JOINED) {
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
+ "Relay begin cell at non-server. Closing.");
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ END_STREAM_REASON_EXITPOLICY, NULL);
+ return 0;
+ }
+
+ rv = begin_cell_parse(cell, &bcell, &end_reason);
+ if (rv < -1) {
+ return -END_CIRC_REASON_TORPROTOCOL;
+ } else if (rv == -1) {
+ tor_free(bcell.address);
+ relay_send_end_cell_from_edge(rh.stream_id, circ, end_reason, layer_hint);
+ return 0;
+ }
+
+ if (! bcell.is_begindir) {
+ /* Steal reference */
+ address = bcell.address;
+ port = bcell.port;
+
+ if (or_circ && or_circ->p_chan) {
+ const int client_chan = channel_is_client(or_circ->p_chan);
+ if ((client_chan ||
+ (!connection_or_digest_is_known_relay(
+ or_circ->p_chan->identity_digest) &&
+ should_refuse_unknown_exits(options)))) {
+ /* Don't let clients use us as a single-hop proxy. It attracts
+ * attackers and users who'd be better off with, well, single-hop
+ * proxies. */
+ log_fn(LOG_PROTOCOL_WARN, LD_PROTOCOL,
+ "Attempt by %s to open a stream %s. Closing.",
+ safe_str(channel_get_canonical_remote_descr(or_circ->p_chan)),
+ client_chan ? "on first hop of circuit" :
+ "from unknown relay");
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ client_chan ?
+ END_STREAM_REASON_TORPROTOCOL :
+ END_STREAM_REASON_MISC,
+ NULL);
+ tor_free(address);
+ return 0;
+ }
+ }
+ } else if (rh.command == RELAY_COMMAND_BEGIN_DIR) {
+ if (!directory_permits_begindir_requests(options) ||
+ circ->purpose != CIRCUIT_PURPOSE_OR) {
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ END_STREAM_REASON_NOTDIRECTORY, layer_hint);
+ return 0;
+ }
+ /* Make sure to get the 'real' address of the previous hop: the
+ * caller might want to know whether the remote IP address has changed,
+ * and we might already have corrected base_.addr[ess] for the relay's
+ * canonical IP address. */
+ if (or_circ && or_circ->p_chan)
+ address = tor_strdup(channel_get_actual_remote_address(or_circ->p_chan));
+ else
+ address = tor_strdup("127.0.0.1");
+ port = 1; /* XXXX This value is never actually used anywhere, and there
+ * isn't "really" a connection here. But we
+ * need to set it to something nonzero. */
+ } else {
+ log_warn(LD_BUG, "Got an unexpected command %d", (int)rh.command);
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ END_STREAM_REASON_INTERNAL, layer_hint);
+ return 0;
+ }
+
+ if (! options->IPv6Exit) {
+ /* I don't care if you prefer IPv6; I can't give you any. */
+ bcell.flags &= ~BEGIN_FLAG_IPV6_PREFERRED;
+ /* If you don't want IPv4, I can't help. */
+ if (bcell.flags & BEGIN_FLAG_IPV4_NOT_OK) {
+ tor_free(address);
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ END_STREAM_REASON_EXITPOLICY, layer_hint);
+ return 0;
+ }
+ }
+
+ log_debug(LD_EXIT,"Creating new exit connection.");
+ /* The 'AF_INET' here is temporary; we might need to change it later in
+ * connection_exit_connect(). */
+ n_stream = edge_connection_new(CONN_TYPE_EXIT, AF_INET);
+
+ /* Remember the tunneled request ID in the new edge connection, so that
+ * we can measure download times. */
+ n_stream->dirreq_id = circ->dirreq_id;
+
+ n_stream->base_.purpose = EXIT_PURPOSE_CONNECT;
+ n_stream->begincell_flags = bcell.flags;
+ n_stream->stream_id = rh.stream_id;
+ n_stream->base_.port = port;
+ /* leave n_stream->s at -1, because it's not yet valid */
+ n_stream->package_window = STREAMWINDOW_START;
+ n_stream->deliver_window = STREAMWINDOW_START;
+
+ if (circ->purpose == CIRCUIT_PURPOSE_S_REND_JOINED) {
+ int ret;
+ tor_free(address);
+ /* We handle this circuit and stream in this function for all supported
+ * hidden service version. */
+ ret = handle_hs_exit_conn(circ, n_stream);
+
+ if (ret == 0) {
+ /* This was a valid cell. Count it as delivered + overhead. */
+ circuit_read_valid_data(origin_circ, rh.length);
+ }
+ return ret;
+ }
+ tor_strlower(address);
+ n_stream->base_.address = address;
+ n_stream->base_.state = EXIT_CONN_STATE_RESOLVEFAILED;
+ /* default to failed, change in dns_resolve if it turns out not to fail */
+
+ /* If we're hibernating or shutting down, we refuse to open new streams. */
+ if (we_are_hibernating()) {
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ END_STREAM_REASON_HIBERNATING, NULL);
+ connection_free_(TO_CONN(n_stream));
+ return 0;
+ }
+
+ n_stream->on_circuit = circ;
+
+ if (rh.command == RELAY_COMMAND_BEGIN_DIR) {
+ tor_addr_t tmp_addr;
+ tor_assert(or_circ);
+ if (or_circ->p_chan &&
+ channel_get_addr_if_possible(or_circ->p_chan, &tmp_addr)) {
+ tor_addr_copy(&n_stream->base_.addr, &tmp_addr);
+ }
+ return connection_exit_connect_dir(n_stream);
+ }
+
+ log_debug(LD_EXIT,"about to start the dns_resolve().");
+
+ /* send it off to the gethostbyname farm */
+ switch (dns_resolve(n_stream)) {
+ case 1: /* resolve worked; now n_stream is attached to circ. */
+ assert_circuit_ok(circ);
+ log_debug(LD_EXIT,"about to call connection_exit_connect().");
+ connection_exit_connect(n_stream);
+ return 0;
+ case -1: /* resolve failed */
+ relay_send_end_cell_from_edge(rh.stream_id, circ,
+ END_STREAM_REASON_RESOLVEFAILED, NULL);
+ /* n_stream got freed. don't touch it. */
+ break;
+ case 0: /* resolve added to pending list */
+ assert_circuit_ok(circ);
+ break;
+ }
+ return 0;
+}
+
+/**
+ * Called when we receive a RELAY_COMMAND_RESOLVE cell 'cell' along the
+ * circuit <b>circ</b>;
+ * begin resolving the hostname, and (eventually) reply with a RESOLVED cell.
+ */
+int
+connection_exit_begin_resolve(cell_t *cell, or_circuit_t *circ)
+{
+ edge_connection_t *dummy_conn;
+ relay_header_t rh;
+
+ assert_circuit_ok(TO_CIRCUIT(circ));
+ relay_header_unpack(&rh, cell->payload);
+ if (rh.length > RELAY_PAYLOAD_SIZE)
+ return -1;
+
+ /* This 'dummy_conn' only exists to remember the stream ID
+ * associated with the resolve request; and to make the
+ * implementation of dns.c more uniform. (We really only need to
+ * remember the circuit, the stream ID, and the hostname to be
+ * resolved; but if we didn't store them in a connection like this,
+ * the housekeeping in dns.c would get way more complicated.)
+ */
+ dummy_conn = edge_connection_new(CONN_TYPE_EXIT, AF_INET);
+ dummy_conn->stream_id = rh.stream_id;
+ dummy_conn->base_.address = tor_strndup(
+ (char*)cell->payload+RELAY_HEADER_SIZE,
+ rh.length);
+ dummy_conn->base_.port = 0;
+ dummy_conn->base_.state = EXIT_CONN_STATE_RESOLVEFAILED;
+ dummy_conn->base_.purpose = EXIT_PURPOSE_RESOLVE;
+
+ dummy_conn->on_circuit = TO_CIRCUIT(circ);
+
+ /* send it off to the gethostbyname farm */
+ switch (dns_resolve(dummy_conn)) {
+ case -1: /* Impossible to resolve; a resolved cell was sent. */
+ /* Connection freed; don't touch it. */
+ return 0;
+ case 1: /* The result was cached; a resolved cell was sent. */
+ if (!dummy_conn->base_.marked_for_close)
+ connection_free_(TO_CONN(dummy_conn));
+ return 0;
+ case 0: /* resolve added to pending list */
+ assert_circuit_ok(TO_CIRCUIT(circ));
+ break;
+ }
+ return 0;
+}
+
+/** Helper: Return true and set *<b>why_rejected</b> to an optional clarifying
+ * message message iff we do not allow connections to <b>addr</b>:<b>port</b>.
+ */
+static int
+my_exit_policy_rejects(const tor_addr_t *addr,
+ uint16_t port,
+ const char **why_rejected)
+{
+ if (router_compare_to_my_exit_policy(addr, port)) {
+ *why_rejected = "";
+ return 1;
+ } else if (tor_addr_family(addr) == AF_INET6 && !get_options()->IPv6Exit) {
+ *why_rejected = " (IPv6 address without IPv6Exit configured)";
+ return 1;
+ }
+ return 0;
+}
+
+/** Connect to conn's specified addr and port. If it worked, conn
+ * has now been added to the connection_array.
+ *
+ * Send back a connected cell. Include the resolved IP of the destination
+ * address, but <em>only</em> if it's a general exit stream. (Rendezvous
+ * streams must not reveal what IP they connected to.)
+ */
+void
+connection_exit_connect(edge_connection_t *edge_conn)
+{
+ const tor_addr_t *addr;
+ uint16_t port;
+ connection_t *conn = TO_CONN(edge_conn);
+ int socket_error = 0, result;
+ const char *why_failed_exit_policy = NULL;
+
+ /* Apply exit policy to non-rendezvous connections. */
+ if (! connection_edge_is_rendezvous_stream(edge_conn) &&
+ my_exit_policy_rejects(&edge_conn->base_.addr,
+ edge_conn->base_.port,
+ &why_failed_exit_policy)) {
+ if (BUG(!why_failed_exit_policy))
+ why_failed_exit_policy = "";
+ log_info(LD_EXIT,"%s:%d failed exit policy%s. Closing.",
+ escaped_safe_str_client(conn->address), conn->port,
+ why_failed_exit_policy);
+ connection_edge_end(edge_conn, END_STREAM_REASON_EXITPOLICY);
+ circuit_detach_stream(circuit_get_by_edge_conn(edge_conn), edge_conn);
+ connection_free(conn);
+ return;
+ }
+
+#ifdef HAVE_SYS_UN_H
+ if (conn->socket_family != AF_UNIX) {
+#else
+ {
+#endif /* defined(HAVE_SYS_UN_H) */
+ addr = &conn->addr;
+ port = conn->port;
+
+ if (tor_addr_family(addr) == AF_INET6)
+ conn->socket_family = AF_INET6;
+
+ log_debug(LD_EXIT, "about to try connecting");
+ result = connection_connect(conn, conn->address,
+ addr, port, &socket_error);
+#ifdef HAVE_SYS_UN_H
+ } else {
+ /*
+ * In the AF_UNIX case, we expect to have already had conn->port = 1,
+ * tor_addr_make_unspec(conn->addr) (cf. the way we mark in the incoming
+ * case in connection_handle_listener_read()), and conn->address should
+ * have the socket path to connect to.
+ */
+ tor_assert(conn->address && strlen(conn->address) > 0);
+
+ log_debug(LD_EXIT, "about to try connecting");
+ result = connection_connect_unix(conn, conn->address, &socket_error);
+#endif /* defined(HAVE_SYS_UN_H) */
+ }
+
+ switch (result) {
+ case -1: {
+ int reason = errno_to_stream_end_reason(socket_error);
+ connection_edge_end(edge_conn, reason);
+ circuit_detach_stream(circuit_get_by_edge_conn(edge_conn), edge_conn);
+ connection_free(conn);
+ return;
+ }
+ case 0:
+ conn->state = EXIT_CONN_STATE_CONNECTING;
+
+ connection_watch_events(conn, READ_EVENT | WRITE_EVENT);
+ /* writable indicates finish;
+ * readable/error indicates broken link in windows-land. */
+ return;
+ /* case 1: fall through */
+ }
+
+ conn->state = EXIT_CONN_STATE_OPEN;
+ if (connection_get_outbuf_len(conn)) {
+ /* in case there are any queued data cells, from e.g. optimistic data */
+ connection_watch_events(conn, READ_EVENT|WRITE_EVENT);
+ } else {
+ connection_watch_events(conn, READ_EVENT);
+ }
+
+ /* also, deliver a 'connected' cell back through the circuit. */
+ if (connection_edge_is_rendezvous_stream(edge_conn)) {
+ /* don't send an address back! */
+ connection_edge_send_command(edge_conn,
+ RELAY_COMMAND_CONNECTED,
+ NULL, 0);
+ } else { /* normal stream */
+ uint8_t connected_payload[MAX_CONNECTED_CELL_PAYLOAD_LEN];
+ int connected_payload_len =
+ connected_cell_format_payload(connected_payload, &conn->addr,
+ edge_conn->address_ttl);
+ if (connected_payload_len < 0) {
+ connection_edge_end(edge_conn, END_STREAM_REASON_INTERNAL);
+ circuit_detach_stream(circuit_get_by_edge_conn(edge_conn), edge_conn);
+ connection_free(conn);
+ return;
+ }
+
+ connection_edge_send_command(edge_conn,
+ RELAY_COMMAND_CONNECTED,
+ (char*)connected_payload,
+ connected_payload_len);
+ }
+}
+
+/** Given an exit conn that should attach to us as a directory server, open a
+ * bridge connection with a linked connection pair, create a new directory
+ * conn, and join them together. Return 0 on success (or if there was an
+ * error we could send back an end cell for). Return -(some circuit end
+ * reason) if the circuit needs to be torn down. Either connects
+ * <b>exitconn</b>, frees it, or marks it, as appropriate.
+ */
+static int
+connection_exit_connect_dir(edge_connection_t *exitconn)
+{
+ dir_connection_t *dirconn = NULL;
+ or_circuit_t *circ = TO_OR_CIRCUIT(exitconn->on_circuit);
+
+ log_info(LD_EXIT, "Opening local connection for anonymized directory exit");
+
+ exitconn->base_.state = EXIT_CONN_STATE_OPEN;
+
+ dirconn = dir_connection_new(tor_addr_family(&exitconn->base_.addr));
+
+ tor_addr_copy(&dirconn->base_.addr, &exitconn->base_.addr);
+ dirconn->base_.port = 0;
+ dirconn->base_.address = tor_strdup(exitconn->base_.address);
+ dirconn->base_.type = CONN_TYPE_DIR;
+ dirconn->base_.purpose = DIR_PURPOSE_SERVER;
+ dirconn->base_.state = DIR_CONN_STATE_SERVER_COMMAND_WAIT;
+
+ /* Note that the new dir conn belongs to the same tunneled request as
+ * the edge conn, so that we can measure download times. */
+ dirconn->dirreq_id = exitconn->dirreq_id;
+
+ connection_link_connections(TO_CONN(dirconn), TO_CONN(exitconn));
+
+ if (connection_add(TO_CONN(exitconn))<0) {
+ connection_edge_end(exitconn, END_STREAM_REASON_RESOURCELIMIT);
+ connection_free_(TO_CONN(exitconn));
+ connection_free_(TO_CONN(dirconn));
+ return 0;
+ }
+
+ /* link exitconn to circ, now that we know we can use it. */
+ exitconn->next_stream = circ->n_streams;
+ circ->n_streams = exitconn;
+
+ if (connection_add(TO_CONN(dirconn))<0) {
+ connection_edge_end(exitconn, END_STREAM_REASON_RESOURCELIMIT);
+ connection_close_immediate(TO_CONN(exitconn));
+ connection_mark_for_close(TO_CONN(exitconn));
+ connection_free_(TO_CONN(dirconn));
+ return 0;
+ }
+
+ connection_start_reading(TO_CONN(dirconn));
+ connection_start_reading(TO_CONN(exitconn));
+
+ if (connection_edge_send_command(exitconn,
+ RELAY_COMMAND_CONNECTED, NULL, 0) < 0) {
+ connection_mark_for_close(TO_CONN(exitconn));
+ connection_mark_for_close(TO_CONN(dirconn));
+ return 0;
+ }
+
+ return 0;
+}
+
+/** Return 1 if <b>conn</b> is a rendezvous stream, or 0 if
+ * it is a general stream.
+ */
+int
+connection_edge_is_rendezvous_stream(const edge_connection_t *conn)
+{
+ tor_assert(conn);
+ /* It should not be possible to set both of these structs */
+ tor_assert_nonfatal(!(conn->rend_data && conn->hs_ident));
+
+ if (conn->rend_data || conn->hs_ident) {
+ return 1;
+ }
+ return 0;
+}
+
+/** Return 1 if router <b>exit_node</b> is likely to allow stream <b>conn</b>
+ * to exit from it, or 0 if it probably will not allow it.
+ * (We might be uncertain if conn's destination address has not yet been
+ * resolved.)
+ */
+int
+connection_ap_can_use_exit(const entry_connection_t *conn,
+ const node_t *exit_node)
+{
+ const or_options_t *options = get_options();
+
+ tor_assert(conn);
+ tor_assert(conn->socks_request);
+ tor_assert(exit_node);
+
+ /* If a particular exit node has been requested for the new connection,
+ * make sure the exit node of the existing circuit matches exactly.
+ */
+ if (conn->chosen_exit_name) {
+ const node_t *chosen_exit =
+ node_get_by_nickname(conn->chosen_exit_name, 0);
+ if (!chosen_exit || tor_memneq(chosen_exit->identity,
+ exit_node->identity, DIGEST_LEN)) {
+ /* doesn't match */
+// log_debug(LD_APP,"Requested node '%s', considering node '%s'. No.",
+// conn->chosen_exit_name, exit->nickname);
+ return 0;
+ }
+ }
+
+ if (conn->use_begindir) {
+ /* Internal directory fetches do not count as exiting. */
+ return 1;
+ }
+
+ if (conn->socks_request->command == SOCKS_COMMAND_CONNECT) {
+ tor_addr_t addr, *addrp = NULL;
+ addr_policy_result_t r;
+ if (0 == tor_addr_parse(&addr, conn->socks_request->address)) {
+ addrp = &addr;
+ } else if (!conn->entry_cfg.ipv4_traffic && conn->entry_cfg.ipv6_traffic) {
+ tor_addr_make_null(&addr, AF_INET6);
+ addrp = &addr;
+ } else if (conn->entry_cfg.ipv4_traffic && !conn->entry_cfg.ipv6_traffic) {
+ tor_addr_make_null(&addr, AF_INET);
+ addrp = &addr;
+ }
+ r = compare_tor_addr_to_node_policy(addrp, conn->socks_request->port,
+ exit_node);
+ if (r == ADDR_POLICY_REJECTED)
+ return 0; /* We know the address, and the exit policy rejects it. */
+ if (r == ADDR_POLICY_PROBABLY_REJECTED && !conn->chosen_exit_name)
+ return 0; /* We don't know the addr, but the exit policy rejects most
+ * addresses with this port. Since the user didn't ask for
+ * this node, err on the side of caution. */
+ } else if (SOCKS_COMMAND_IS_RESOLVE(conn->socks_request->command)) {
+ /* Don't send DNS requests to non-exit servers by default. */
+ if (!conn->chosen_exit_name && node_exit_policy_rejects_all(exit_node))
+ return 0;
+ }
+ if (routerset_contains_node(options->ExcludeExitNodesUnion_, exit_node)) {
+ /* Not a suitable exit. Refuse it. */
+ return 0;
+ }
+
+ return 1;
+}
+
+/** If address is of the form "y.onion" with a well-formed handle y:
+ * Put a NUL after y, lower-case it, and return ONION_V2_HOSTNAME or
+ * ONION_V3_HOSTNAME depending on the HS version.
+ *
+ * If address is of the form "x.y.onion" with a well-formed handle x:
+ * Drop "x.", put a NUL after y, lower-case it, and return
+ * ONION_V2_HOSTNAME or ONION_V3_HOSTNAME depending on the HS version.
+ *
+ * If address is of the form "y.onion" with a badly-formed handle y:
+ * Return BAD_HOSTNAME and log a message.
+ *
+ * If address is of the form "y.exit":
+ * Put a NUL after y and return EXIT_HOSTNAME.
+ *
+ * Otherwise:
+ * Return NORMAL_HOSTNAME and change nothing.
+ */
+hostname_type_t
+parse_extended_hostname(char *address)
+{
+ char *s;
+ char *q;
+ char query[HS_SERVICE_ADDR_LEN_BASE32+1];
+
+ s = strrchr(address,'.');
+ if (!s)
+ return NORMAL_HOSTNAME; /* no dot, thus normal */
+ if (!strcmp(s+1,"exit")) {
+ *s = 0; /* NUL-terminate it */
+ return EXIT_HOSTNAME; /* .exit */
+ }
+ if (strcmp(s+1,"onion"))
+ return NORMAL_HOSTNAME; /* neither .exit nor .onion, thus normal */
+
+ /* so it is .onion */
+ *s = 0; /* NUL-terminate it */
+ /* locate a 'sub-domain' component, in order to remove it */
+ q = strrchr(address, '.');
+ if (q == address) {
+ goto failed; /* reject sub-domain, as DNS does */
+ }
+ q = (NULL == q) ? address : q + 1;
+ if (strlcpy(query, q, HS_SERVICE_ADDR_LEN_BASE32+1) >=
+ HS_SERVICE_ADDR_LEN_BASE32+1)
+ goto failed;
+ if (q != address) {
+ memmove(address, q, strlen(q) + 1 /* also get \0 */);
+ }
+ if (rend_valid_v2_service_id(query)) {
+ return ONION_V2_HOSTNAME; /* success */
+ }
+ if (hs_address_is_valid(query)) {
+ return ONION_V3_HOSTNAME;
+ }
+ failed:
+ /* otherwise, return to previous state and return 0 */
+ *s = '.';
+ log_warn(LD_APP, "Invalid onion hostname %s; rejecting",
+ safe_str_client(address));
+ return BAD_HOSTNAME;
+}
+
+/** Return true iff the (possibly NULL) <b>alen</b>-byte chunk of memory at
+ * <b>a</b> is equal to the (possibly NULL) <b>blen</b>-byte chunk of memory
+ * at <b>b</b>. */
+static int
+memeq_opt(const char *a, size_t alen, const char *b, size_t blen)
+{
+ if (a == NULL) {
+ return (b == NULL);
+ } else if (b == NULL) {
+ return 0;
+ } else if (alen != blen) {
+ return 0;
+ } else {
+ return tor_memeq(a, b, alen);
+ }
+}
+
+/**
+ * Return true iff none of the isolation flags and fields in <b>conn</b>
+ * should prevent it from being attached to <b>circ</b>.
+ */
+int
+connection_edge_compatible_with_circuit(const entry_connection_t *conn,
+ const origin_circuit_t *circ)
+{
+ const uint8_t iso = conn->entry_cfg.isolation_flags;
+ const socks_request_t *sr = conn->socks_request;
+
+ /* If circ has never been used for an isolated connection, we can
+ * totally use it for this one. */
+ if (!circ->isolation_values_set)
+ return 1;
+
+ /* If circ has been used for connections having more than one value
+ * for some field f, it will have the corresponding bit set in
+ * isolation_flags_mixed. If isolation_flags_mixed has any bits
+ * in common with iso, then conn must be isolated from at least
+ * one stream that has been attached to circ. */
+ if ((iso & circ->isolation_flags_mixed) != 0) {
+ /* For at least one field where conn is isolated, the circuit
+ * already has mixed streams. */
+ return 0;
+ }
+
+ if (! conn->original_dest_address) {
+ log_warn(LD_BUG, "Reached connection_edge_compatible_with_circuit without "
+ "having set conn->original_dest_address");
+ ((entry_connection_t*)conn)->original_dest_address =
+ tor_strdup(conn->socks_request->address);
+ }
+
+ if ((iso & ISO_STREAM) &&
+ (circ->associated_isolated_stream_global_id !=
+ ENTRY_TO_CONN(conn)->global_identifier))
+ return 0;
+
+ if ((iso & ISO_DESTPORT) && conn->socks_request->port != circ->dest_port)
+ return 0;
+ if ((iso & ISO_DESTADDR) &&
+ strcasecmp(conn->original_dest_address, circ->dest_address))
+ return 0;
+ if ((iso & ISO_SOCKSAUTH) &&
+ (! memeq_opt(sr->username, sr->usernamelen,
+ circ->socks_username, circ->socks_username_len) ||
+ ! memeq_opt(sr->password, sr->passwordlen,
+ circ->socks_password, circ->socks_password_len)))
+ return 0;
+ if ((iso & ISO_CLIENTPROTO) &&
+ (conn->socks_request->listener_type != circ->client_proto_type ||
+ conn->socks_request->socks_version != circ->client_proto_socksver))
+ return 0;
+ if ((iso & ISO_CLIENTADDR) &&
+ !tor_addr_eq(&ENTRY_TO_CONN(conn)->addr, &circ->client_addr))
+ return 0;
+ if ((iso & ISO_SESSIONGRP) &&
+ conn->entry_cfg.session_group != circ->session_group)
+ return 0;
+ if ((iso & ISO_NYM_EPOCH) && conn->nym_epoch != circ->nym_epoch)
+ return 0;
+
+ return 1;
+}
+
+/**
+ * If <b>dry_run</b> is false, update <b>circ</b>'s isolation flags and fields
+ * to reflect having had <b>conn</b> attached to it, and return 0. Otherwise,
+ * if <b>dry_run</b> is true, then make no changes to <b>circ</b>, and return
+ * a bitfield of isolation flags that we would have to set in
+ * isolation_flags_mixed to add <b>conn</b> to <b>circ</b>, or -1 if
+ * <b>circ</b> has had no streams attached to it.
+ */
+int
+connection_edge_update_circuit_isolation(const entry_connection_t *conn,
+ origin_circuit_t *circ,
+ int dry_run)
+{
+ const socks_request_t *sr = conn->socks_request;
+ if (! conn->original_dest_address) {
+ log_warn(LD_BUG, "Reached connection_update_circuit_isolation without "
+ "having set conn->original_dest_address");
+ ((entry_connection_t*)conn)->original_dest_address =
+ tor_strdup(conn->socks_request->address);
+ }
+
+ if (!circ->isolation_values_set) {
+ if (dry_run)
+ return -1;
+ circ->associated_isolated_stream_global_id =
+ ENTRY_TO_CONN(conn)->global_identifier;
+ circ->dest_port = conn->socks_request->port;
+ circ->dest_address = tor_strdup(conn->original_dest_address);
+ circ->client_proto_type = conn->socks_request->listener_type;
+ circ->client_proto_socksver = conn->socks_request->socks_version;
+ tor_addr_copy(&circ->client_addr, &ENTRY_TO_CONN(conn)->addr);
+ circ->session_group = conn->entry_cfg.session_group;
+ circ->nym_epoch = conn->nym_epoch;
+ circ->socks_username = sr->username ?
+ tor_memdup(sr->username, sr->usernamelen) : NULL;
+ circ->socks_password = sr->password ?
+ tor_memdup(sr->password, sr->passwordlen) : NULL;
+ circ->socks_username_len = sr->usernamelen;
+ circ->socks_password_len = sr->passwordlen;
+
+ circ->isolation_values_set = 1;
+ return 0;
+ } else {
+ uint8_t mixed = 0;
+ if (conn->socks_request->port != circ->dest_port)
+ mixed |= ISO_DESTPORT;
+ if (strcasecmp(conn->original_dest_address, circ->dest_address))
+ mixed |= ISO_DESTADDR;
+ if (!memeq_opt(sr->username, sr->usernamelen,
+ circ->socks_username, circ->socks_username_len) ||
+ !memeq_opt(sr->password, sr->passwordlen,
+ circ->socks_password, circ->socks_password_len))
+ mixed |= ISO_SOCKSAUTH;
+ if ((conn->socks_request->listener_type != circ->client_proto_type ||
+ conn->socks_request->socks_version != circ->client_proto_socksver))
+ mixed |= ISO_CLIENTPROTO;
+ if (!tor_addr_eq(&ENTRY_TO_CONN(conn)->addr, &circ->client_addr))
+ mixed |= ISO_CLIENTADDR;
+ if (conn->entry_cfg.session_group != circ->session_group)
+ mixed |= ISO_SESSIONGRP;
+ if (conn->nym_epoch != circ->nym_epoch)
+ mixed |= ISO_NYM_EPOCH;
+
+ if (dry_run)
+ return mixed;
+
+ if ((mixed & conn->entry_cfg.isolation_flags) != 0) {
+ log_warn(LD_BUG, "Updating a circuit with seemingly incompatible "
+ "isolation flags.");
+ }
+ circ->isolation_flags_mixed |= mixed;
+ return 0;
+ }
+}
+
+/**
+ * Clear the isolation settings on <b>circ</b>.
+ *
+ * This only works on an open circuit that has never had a stream attached to
+ * it, and whose isolation settings are hypothetical. (We set hypothetical
+ * isolation settings on circuits as we're launching them, so that we
+ * know whether they can handle more streams or whether we need to launch
+ * even more circuits. Once the circuit is open, if it turns out that
+ * we no longer have any streams to attach to it, we clear the isolation flags
+ * and data so that other streams can have a chance.)
+ */
+void
+circuit_clear_isolation(origin_circuit_t *circ)
+{
+ if (circ->isolation_any_streams_attached) {
+ log_warn(LD_BUG, "Tried to clear the isolation status of a dirty circuit");
+ return;
+ }
+ if (TO_CIRCUIT(circ)->state != CIRCUIT_STATE_OPEN) {
+ log_warn(LD_BUG, "Tried to clear the isolation status of a non-open "
+ "circuit");
+ return;
+ }
+
+ circ->isolation_values_set = 0;
+ circ->isolation_flags_mixed = 0;
+ circ->associated_isolated_stream_global_id = 0;
+ circ->client_proto_type = 0;
+ circ->client_proto_socksver = 0;
+ circ->dest_port = 0;
+ tor_addr_make_unspec(&circ->client_addr);
+ tor_free(circ->dest_address);
+ circ->session_group = -1;
+ circ->nym_epoch = 0;
+ if (circ->socks_username) {
+ memwipe(circ->socks_username, 0x11, circ->socks_username_len);
+ tor_free(circ->socks_username);
+ }
+ if (circ->socks_password) {
+ memwipe(circ->socks_password, 0x05, circ->socks_password_len);
+ tor_free(circ->socks_password);
+ }
+ circ->socks_username_len = circ->socks_password_len = 0;
+}
+
+/** Free all storage held in module-scoped variables for connection_edge.c */
+void
+connection_edge_free_all(void)
+{
+ untried_pending_connections = 0;
+ smartlist_free(pending_entry_connections);
+ pending_entry_connections = NULL;
+ mainloop_event_free(attach_pending_entry_connections_ev);
+}
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