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-rw-r--r--forward.c1531
1 files changed, 0 insertions, 1531 deletions
diff --git a/forward.c b/forward.c
deleted file mode 100644
index 87d05cc..0000000
--- a/forward.c
+++ /dev/null
@@ -1,1531 +0,0 @@
-/*
- * OpenVPN -- An application to securely tunnel IP networks
- * over a single TCP/UDP port, with support for SSL/TLS-based
- * session authentication and key exchange,
- * packet encryption, packet authentication, and
- * packet compression.
- *
- * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program (see the file COPYING included with this
- * distribution); if not, write to the Free Software Foundation, Inc.,
- * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- */
-
-#include "syshead.h"
-
-#include "forward.h"
-#include "init.h"
-#include "push.h"
-#include "gremlin.h"
-#include "mss.h"
-#include "event.h"
-#include "ps.h"
-#include "dhcp.h"
-#include "common.h"
-
-#include "memdbg.h"
-
-#include "forward-inline.h"
-#include "occ-inline.h"
-#include "ping-inline.h"
-
-counter_type link_read_bytes_global; /* GLOBAL */
-counter_type link_write_bytes_global; /* GLOBAL */
-
-/* show event wait debugging info */
-
-#ifdef ENABLE_DEBUG
-
-const char *
-wait_status_string (struct context *c, struct gc_arena *gc)
-{
- struct buffer out = alloc_buf_gc (64, gc);
- buf_printf (&out, "I/O WAIT %s|%s|%s|%s %s",
- tun_stat (c->c1.tuntap, EVENT_READ, gc),
- tun_stat (c->c1.tuntap, EVENT_WRITE, gc),
- socket_stat (c->c2.link_socket, EVENT_READ, gc),
- socket_stat (c->c2.link_socket, EVENT_WRITE, gc),
- tv_string (&c->c2.timeval, gc));
- return BSTR (&out);
-}
-
-void
-show_wait_status (struct context *c)
-{
- struct gc_arena gc = gc_new ();
- dmsg (D_EVENT_WAIT, "%s", wait_status_string (c, &gc));
- gc_free (&gc);
-}
-
-#endif
-
-/*
- * In TLS mode, let TLS level respond to any control-channel
- * packets which were received, or prepare any packets for
- * transmission.
- *
- * tmp_int is purely an optimization that allows us to call
- * tls_multi_process less frequently when there's not much
- * traffic on the control-channel.
- *
- */
-#if defined(USE_CRYPTO) && defined(USE_SSL)
-void
-check_tls_dowork (struct context *c)
-{
- interval_t wakeup = BIG_TIMEOUT;
-
- if (interval_test (&c->c2.tmp_int))
- {
- const int tmp_status = tls_multi_process
- (c->c2.tls_multi, &c->c2.to_link, &c->c2.to_link_addr,
- get_link_socket_info (c), &wakeup);
- if (tmp_status == TLSMP_ACTIVE)
- {
- update_time ();
- interval_action (&c->c2.tmp_int);
- }
- else if (tmp_status == TLSMP_KILL)
- {
- c->sig->signal_received = SIGTERM;
- c->sig->signal_text = "auth-control-exit";
- }
-
- interval_future_trigger (&c->c2.tmp_int, wakeup);
- }
-
- interval_schedule_wakeup (&c->c2.tmp_int, &wakeup);
-
- if (wakeup)
- context_reschedule_sec (c, wakeup);
-}
-#endif
-
-#if defined(USE_CRYPTO) && defined(USE_SSL)
-
-void
-check_tls_errors_co (struct context *c)
-{
- msg (D_STREAM_ERRORS, "Fatal TLS error (check_tls_errors_co), restarting");
- c->sig->signal_received = c->c2.tls_exit_signal; /* SOFT-SIGUSR1 -- TLS error */
- c->sig->signal_text = "tls-error";
-}
-
-void
-check_tls_errors_nco (struct context *c)
-{
- c->sig->signal_received = c->c2.tls_exit_signal; /* SOFT-SIGUSR1 -- TLS error */
- c->sig->signal_text = "tls-error";
-}
-
-#endif
-
-#if P2MP
-
-/*
- * Handle incoming configuration
- * messages on the control channel.
- */
-void
-check_incoming_control_channel_dowork (struct context *c)
-{
- const int len = tls_test_payload_len (c->c2.tls_multi);
- if (len)
- {
- struct gc_arena gc = gc_new ();
- struct buffer buf = alloc_buf_gc (len, &gc);
- if (tls_rec_payload (c->c2.tls_multi, &buf))
- {
- /* force null termination of message */
- buf_null_terminate (&buf);
-
- /* enforce character class restrictions */
- string_mod (BSTR (&buf), CC_PRINT, CC_CRLF, 0);
-
- if (buf_string_match_head_str (&buf, "AUTH_FAILED"))
- receive_auth_failed (c, &buf);
- else if (buf_string_match_head_str (&buf, "PUSH_"))
- incoming_push_message (c, &buf);
- else if (buf_string_match_head_str (&buf, "RESTART"))
- server_pushed_restart (c, &buf);
- else
- msg (D_PUSH_ERRORS, "WARNING: Received unknown control message: %s", BSTR (&buf));
- }
- else
- {
- msg (D_PUSH_ERRORS, "WARNING: Receive control message failed");
- }
-
- gc_free (&gc);
- }
-}
-
-/*
- * Periodically resend PUSH_REQUEST until PUSH message received
- */
-void
-check_push_request_dowork (struct context *c)
-{
- send_push_request (c);
-
- /* if no response to first push_request, retry at 5 second intervals */
- event_timeout_modify_wakeup (&c->c2.push_request_interval, 5);
-}
-
-#endif /* P2MP */
-
-/*
- * Things that need to happen immediately after connection initiation should go here.
- */
-void
-check_connection_established_dowork (struct context *c)
-{
- if (event_timeout_trigger (&c->c2.wait_for_connect, &c->c2.timeval, ETT_DEFAULT))
- {
- if (CONNECTION_ESTABLISHED (c))
- {
-#if P2MP
- /* if --pull was specified, send a push request to server */
- if (c->c2.tls_multi && c->options.pull)
- {
-#ifdef ENABLE_MANAGEMENT
- if (management)
- {
- management_set_state (management,
- OPENVPN_STATE_GET_CONFIG,
- NULL,
- 0,
- 0);
- }
-#endif
- /* send push request in 1 sec */
- event_timeout_init (&c->c2.push_request_interval, 1, now);
- reset_coarse_timers (c);
- }
- else
-#endif
- {
- do_up (c, false, 0);
- }
-
- event_timeout_clear (&c->c2.wait_for_connect);
- }
- }
-}
-
-/*
- * Send a string to remote over the TLS control channel.
- * Used for push/pull messages, passing username/password,
- * etc.
- */
-bool
-send_control_channel_string (struct context *c, const char *str, int msglevel)
-{
-#if defined(USE_CRYPTO) && defined(USE_SSL)
-
- if (c->c2.tls_multi) {
- bool stat;
-
- /* buffered cleartext write onto TLS control channel */
- stat = tls_send_payload (c->c2.tls_multi, (uint8_t*) str, strlen (str) + 1);
-
- /* reschedule tls_multi_process */
- interval_action (&c->c2.tmp_int);
- context_immediate_reschedule (c); /* ZERO-TIMEOUT */
-
- msg (msglevel, "SENT CONTROL [%s]: '%s' (status=%d)",
- tls_common_name (c->c2.tls_multi, false),
- str,
- (int) stat);
-
- return stat;
- }
-#endif
- return true;
-}
-
-/*
- * Add routes.
- */
-
-static void
-check_add_routes_action (struct context *c, const bool errors)
-{
- do_route (&c->options, c->c1.route_list, c->c1.tuntap, c->plugins, c->c2.es);
- update_time ();
- event_timeout_clear (&c->c2.route_wakeup);
- event_timeout_clear (&c->c2.route_wakeup_expire);
- initialization_sequence_completed (c, errors ? ISC_ERRORS : 0); /* client/p2p --route-delay was defined */
-}
-
-void
-check_add_routes_dowork (struct context *c)
-{
- if (test_routes (c->c1.route_list, c->c1.tuntap))
- {
- check_add_routes_action (c, false);
- }
- else if (event_timeout_trigger (&c->c2.route_wakeup_expire, &c->c2.timeval, ETT_DEFAULT))
- {
- check_add_routes_action (c, true);
- }
- else
- {
- msg (D_ROUTE, "Route: Waiting for TUN/TAP interface to come up...");
- if (c->c1.tuntap)
- {
- if (!tun_standby (c->c1.tuntap))
- {
- c->sig->signal_received = SIGHUP;
- c->sig->signal_text = "ip-fail";
- c->persist.restart_sleep_seconds = 10;
-#ifdef WIN32
- show_routes (M_INFO|M_NOPREFIX);
- show_adapters (M_INFO|M_NOPREFIX);
-#endif
- }
- }
- update_time ();
- if (c->c2.route_wakeup.n != 1)
- event_timeout_init (&c->c2.route_wakeup, 1, now);
- event_timeout_reset (&c->c2.ping_rec_interval);
- }
-}
-
-/*
- * Should we exit due to inactivity timeout?
- */
-void
-check_inactivity_timeout_dowork (struct context *c)
-{
- msg (M_INFO, "Inactivity timeout (--inactive), exiting");
- c->sig->signal_received = SIGTERM;
- c->sig->signal_text = "inactive";
-}
-
-#if P2MP
-
-void
-check_server_poll_timeout_dowork (struct context *c)
-{
- event_timeout_reset (&c->c2.server_poll_interval);
- if (!tls_initial_packet_received (c->c2.tls_multi))
- {
- msg (M_INFO, "Server poll timeout, restarting");
- c->sig->signal_received = SIGUSR1;
- c->sig->signal_text = "server_poll";
- c->persist.restart_sleep_seconds = -1;
- }
-}
-
-/*
- * Schedule a signal n_seconds from now.
- */
-void
-schedule_exit (struct context *c, const int n_seconds, const int signal)
-{
- tls_set_single_session (c->c2.tls_multi);
- update_time ();
- reset_coarse_timers (c);
- event_timeout_init (&c->c2.scheduled_exit, n_seconds, now);
- c->c2.scheduled_exit_signal = signal;
- msg (D_SCHED_EXIT, "Delayed exit in %d seconds", n_seconds);
-}
-
-/*
- * Scheduled exit?
- */
-void
-check_scheduled_exit_dowork (struct context *c)
-{
- c->sig->signal_received = c->c2.scheduled_exit_signal;
- c->sig->signal_text = "delayed-exit";
-}
-
-#endif
-
-/*
- * Should we write timer-triggered status file.
- */
-void
-check_status_file_dowork (struct context *c)
-{
- if (c->c1.status_output)
- print_status (c, c->c1.status_output);
-}
-
-#ifdef ENABLE_FRAGMENT
-/*
- * Should we deliver a datagram fragment to remote?
- */
-void
-check_fragment_dowork (struct context *c)
-{
- struct link_socket_info *lsi = get_link_socket_info (c);
-
- /* OS MTU Hint? */
- if (lsi->mtu_changed && c->c2.ipv4_tun)
- {
- frame_adjust_path_mtu (&c->c2.frame_fragment, c->c2.link_socket->mtu,
- c->options.ce.proto);
- lsi->mtu_changed = false;
- }
-
- if (fragment_outgoing_defined (c->c2.fragment))
- {
- if (!c->c2.to_link.len)
- {
- /* encrypt a fragment for output to TCP/UDP port */
- ASSERT (fragment_ready_to_send (c->c2.fragment, &c->c2.buf, &c->c2.frame_fragment));
- encrypt_sign (c, false);
- }
- }
-
- fragment_housekeeping (c->c2.fragment, &c->c2.frame_fragment, &c->c2.timeval);
-}
-#endif
-
-/*
- * Buffer reallocation, for use with null encryption.
- */
-static inline void
-buffer_turnover (const uint8_t *orig_buf, struct buffer *dest_stub, struct buffer *src_stub, struct buffer *storage)
-{
- if (orig_buf == src_stub->data && src_stub->data != storage->data)
- {
- buf_assign (storage, src_stub);
- *dest_stub = *storage;
- }
- else
- {
- *dest_stub = *src_stub;
- }
-}
-
-/*
- * Compress, fragment, encrypt and HMAC-sign an outgoing packet.
- * Input: c->c2.buf
- * Output: c->c2.to_link
- */
-void
-encrypt_sign (struct context *c, bool comp_frag)
-{
- struct context_buffers *b = c->c2.buffers;
- const uint8_t *orig_buf = c->c2.buf.data;
-
-#if P2MP_SERVER
- /*
- * Drop non-TLS outgoing packet if client-connect script/plugin
- * has not yet succeeded.
- */
- if (c->c2.context_auth != CAS_SUCCEEDED)
- c->c2.buf.len = 0;
-#endif
-
- if (comp_frag)
- {
-#ifdef USE_LZO
- /* Compress the packet. */
- if (lzo_defined (&c->c2.lzo_compwork))
- lzo_compress (&c->c2.buf, b->lzo_compress_buf, &c->c2.lzo_compwork, &c->c2.frame);
-#endif
-#ifdef ENABLE_FRAGMENT
- if (c->c2.fragment)
- fragment_outgoing (c->c2.fragment, &c->c2.buf, &c->c2.frame_fragment);
-#endif
- }
-
-#ifdef USE_CRYPTO
-#ifdef USE_SSL
- /*
- * If TLS mode, get the key we will use to encrypt
- * the packet.
- */
- if (c->c2.tls_multi)
- {
- tls_pre_encrypt (c->c2.tls_multi, &c->c2.buf, &c->c2.crypto_options);
- }
-#endif
-
- /*
- * Encrypt the packet and write an optional
- * HMAC signature.
- */
- openvpn_encrypt (&c->c2.buf, b->encrypt_buf, &c->c2.crypto_options, &c->c2.frame);
-#endif
- /*
- * Get the address we will be sending the packet to.
- */
- link_socket_get_outgoing_addr (&c->c2.buf, get_link_socket_info (c),
- &c->c2.to_link_addr);
-#ifdef USE_CRYPTO
-#ifdef USE_SSL
- /*
- * In TLS mode, prepend the appropriate one-byte opcode
- * to the packet which identifies it as a data channel
- * packet and gives the low-permutation version of
- * the key-id to the recipient so it knows which
- * decrypt key to use.
- */
- if (c->c2.tls_multi)
- {
- tls_post_encrypt (c->c2.tls_multi, &c->c2.buf);
- }
-#endif
-#endif
-
- /* if null encryption, copy result to read_tun_buf */
- buffer_turnover (orig_buf, &c->c2.to_link, &c->c2.buf, &b->read_tun_buf);
-}
-
-/*
- * Coarse timers work to 1 second resolution.
- */
-static void
-process_coarse_timers (struct context *c)
-{
-#ifdef USE_CRYPTO
- /* flush current packet-id to file once per 60
- seconds if --replay-persist was specified */
- check_packet_id_persist_flush (c);
-#endif
-
- /* should we update status file? */
- check_status_file (c);
-
- /* process connection establishment items */
- check_connection_established (c);
-
-#if P2MP
- /* see if we should send a push_request in response to --pull */
- check_push_request (c);
-#endif
-
-#ifdef PLUGIN_PF
- pf_check_reload (c);
-#endif
-
- /* process --route options */
- check_add_routes (c);
-
- /* possibly exit due to --inactive */
- check_inactivity_timeout (c);
- if (c->sig->signal_received)
- return;
-
- /* restart if ping not received */
- check_ping_restart (c);
- if (c->sig->signal_received)
- return;
-
-#if P2MP
- check_server_poll_timeout (c);
- if (c->sig->signal_received)
- return;
-
- check_scheduled_exit (c);
- if (c->sig->signal_received)
- return;
-#endif
-
-#ifdef ENABLE_OCC
- /* Should we send an OCC_REQUEST message? */
- check_send_occ_req (c);
-
- /* Should we send an MTU load test? */
- check_send_occ_load_test (c);
-
- /* Should we send an OCC_EXIT message to remote? */
- if (c->c2.explicit_exit_notification_time_wait)
- process_explicit_exit_notification_timer_wakeup (c);
-#endif
-
- /* Should we ping the remote? */
- check_ping_send (c);
-}
-
-static void
-check_coarse_timers_dowork (struct context *c)
-{
- const struct timeval save = c->c2.timeval;
- c->c2.timeval.tv_sec = BIG_TIMEOUT;
- c->c2.timeval.tv_usec = 0;
- process_coarse_timers (c);
- c->c2.coarse_timer_wakeup = now + c->c2.timeval.tv_sec;
-
- dmsg (D_INTERVAL, "TIMER: coarse timer wakeup %d seconds", (int) c->c2.timeval.tv_sec);
-
- /* Is the coarse timeout NOT the earliest one? */
- if (c->c2.timeval.tv_sec > save.tv_sec)
- c->c2.timeval = save;
-}
-
-static inline void
-check_coarse_timers (struct context *c)
-{
- const time_t local_now = now;
- if (local_now >= c->c2.coarse_timer_wakeup)
- check_coarse_timers_dowork (c);
- else
- context_reschedule_sec (c, c->c2.coarse_timer_wakeup - local_now);
-}
-
-static void
-check_timeout_random_component_dowork (struct context *c)
-{
- const int update_interval = 10; /* seconds */
- c->c2.update_timeout_random_component = now + update_interval;
- c->c2.timeout_random_component.tv_usec = (time_t) get_random () & 0x0003FFFF;
- c->c2.timeout_random_component.tv_sec = 0;
-
- dmsg (D_INTERVAL, "RANDOM USEC=%d", (int) c->c2.timeout_random_component.tv_usec);
-}
-
-static inline void
-check_timeout_random_component (struct context *c)
-{
- if (now >= c->c2.update_timeout_random_component)
- check_timeout_random_component_dowork (c);
- if (c->c2.timeval.tv_sec >= 1)
- tv_add (&c->c2.timeval, &c->c2.timeout_random_component);
-}
-
-#ifdef ENABLE_SOCKS
-
-/*
- * Handle addition and removal of the 10-byte Socks5 header
- * in UDP packets.
- */
-
-static inline void
-socks_postprocess_incoming_link (struct context *c)
-{
- if (c->c2.link_socket->socks_proxy && c->c2.link_socket->info.proto == PROTO_UDPv4)
- socks_process_incoming_udp (&c->c2.buf, &c->c2.from);
-}
-
-static inline void
-socks_preprocess_outgoing_link (struct context *c,
- struct link_socket_actual **to_addr,
- int *size_delta)
-{
- if (c->c2.link_socket->socks_proxy && c->c2.link_socket->info.proto == PROTO_UDPv4)
- {
- *size_delta += socks_process_outgoing_udp (&c->c2.to_link, c->c2.to_link_addr);
- *to_addr = &c->c2.link_socket->socks_relay;
- }
-}
-
-/* undo effect of socks_preprocess_outgoing_link */
-static inline void
-link_socket_write_post_size_adjust (int *size,
- int size_delta,
- struct buffer *buf)
-{
- if (size_delta > 0 && *size > size_delta)
- {
- *size -= size_delta;
- if (!buf_advance (buf, size_delta))
- *size = 0;
- }
-}
-#endif
-
-/*
- * Output: c->c2.buf
- */
-
-void
-read_incoming_link (struct context *c)
-{
- /*
- * Set up for recvfrom call to read datagram
- * sent to our TCP/UDP port.
- */
- int status;
-
- /*ASSERT (!c->c2.to_tun.len);*/
-
- perf_push (PERF_READ_IN_LINK);
-
- c->c2.buf = c->c2.buffers->read_link_buf;
- ASSERT (buf_init (&c->c2.buf, FRAME_HEADROOM_ADJ (&c->c2.frame, FRAME_HEADROOM_MARKER_READ_LINK)));
-
- status = link_socket_read (c->c2.link_socket,
- &c->c2.buf,
- MAX_RW_SIZE_LINK (&c->c2.frame),
- &c->c2.from);
-
- if (socket_connection_reset (c->c2.link_socket, status))
- {
-#if PORT_SHARE
- if (port_share && socket_foreign_protocol_detected (c->c2.link_socket))
- {
- const struct buffer *fbuf = socket_foreign_protocol_head (c->c2.link_socket);
- const int sd = socket_foreign_protocol_sd (c->c2.link_socket);
- port_share_redirect (port_share, fbuf, sd);
- c->sig->signal_received = SIGTERM;
- c->sig->signal_text = "port-share-redirect";
- }
- else
-#endif
- {
- /* received a disconnect from a connection-oriented protocol */
- if (c->options.inetd)
- {
- c->sig->signal_received = SIGTERM;
- c->sig->signal_text = "connection-reset-inetd";
- msg (D_STREAM_ERRORS, "Connection reset, inetd/xinetd exit [%d]", status);
- }
- else
- {
-#ifdef ENABLE_OCC
- if (event_timeout_defined(&c->c2.explicit_exit_notification_interval))
- {
- msg (D_STREAM_ERRORS, "Connection reset during exit notification period, ignoring [%d]", status);
- openvpn_sleep(1);
- }
- else
-#endif
- {
- c->sig->signal_received = SIGUSR1; /* SOFT-SIGUSR1 -- TCP connection reset */
- c->sig->signal_text = "connection-reset";
- msg (D_STREAM_ERRORS, "Connection reset, restarting [%d]", status);
- }
- }
- }
- perf_pop ();
- return;
- }
-
- /* check recvfrom status */
- check_status (status, "read", c->c2.link_socket, NULL);
-
-#ifdef ENABLE_SOCKS
- /* Remove socks header if applicable */
- socks_postprocess_incoming_link (c);
-#endif
-
- perf_pop ();
-}
-
-/*
- * Input: c->c2.buf
- * Output: c->c2.to_tun
- */
-
-void
-process_incoming_link (struct context *c)
-{
- struct gc_arena gc = gc_new ();
- bool decrypt_status;
- struct link_socket_info *lsi = get_link_socket_info (c);
- const uint8_t *orig_buf = c->c2.buf.data;
-
- perf_push (PERF_PROC_IN_LINK);
-
- if (c->c2.buf.len > 0)
- {
- c->c2.link_read_bytes += c->c2.buf.len;
- link_read_bytes_global += c->c2.buf.len;
- c->c2.original_recv_size = c->c2.buf.len;
-#ifdef ENABLE_MANAGEMENT
- if (management)
- {
- management_bytes_in (management, c->c2.buf.len);
-#ifdef MANAGEMENT_DEF_AUTH
- management_bytes_server (management, &c->c2.link_read_bytes, &c->c2.link_write_bytes, &c->c2.mda_context);
-#endif
- }
-#endif
- }
- else
- c->c2.original_recv_size = 0;
-
-#ifdef ENABLE_DEBUG
- /* take action to corrupt packet if we are in gremlin test mode */
- if (c->options.gremlin) {
- if (!ask_gremlin (c->options.gremlin))
- c->c2.buf.len = 0;
- corrupt_gremlin (&c->c2.buf, c->options.gremlin);
- }
-#endif
-
- /* log incoming packet */
-#ifdef LOG_RW
- if (c->c2.log_rw && c->c2.buf.len > 0)
- fprintf (stderr, "R");
-#endif
- msg (D_LINK_RW, "%s READ [%d] from %s: %s",
- proto2ascii (lsi->proto, true),
- BLEN (&c->c2.buf),
- print_link_socket_actual (&c->c2.from, &gc),
- PROTO_DUMP (&c->c2.buf, &gc));
-
- /*
- * Good, non-zero length packet received.
- * Commence multi-stage processing of packet,
- * such as authenticate, decrypt, decompress.
- * If any stage fails, it sets buf.len to 0 or -1,
- * telling downstream stages to ignore the packet.
- */
- if (c->c2.buf.len > 0)
- {
- if (!link_socket_verify_incoming_addr (&c->c2.buf, lsi, &c->c2.from))
- link_socket_bad_incoming_addr (&c->c2.buf, lsi, &c->c2.from);
-
-#ifdef USE_CRYPTO
-#ifdef USE_SSL
- if (c->c2.tls_multi)
- {
- /*
- * If tls_pre_decrypt returns true, it means the incoming
- * packet was a good TLS control channel packet. If so, TLS code
- * will deal with the packet and set buf.len to 0 so downstream
- * stages ignore it.
- *
- * If the packet is a data channel packet, tls_pre_decrypt
- * will load crypto_options with the correct encryption key
- * and return false.
- */
- if (tls_pre_decrypt (c->c2.tls_multi, &c->c2.from, &c->c2.buf, &c->c2.crypto_options))
- {
- interval_action (&c->c2.tmp_int);
-
- /* reset packet received timer if TLS packet */
- if (c->options.ping_rec_timeout)
- event_timeout_reset (&c->c2.ping_rec_interval);
- }
- }
-#if P2MP_SERVER
- /*
- * Drop non-TLS packet if client-connect script/plugin has not
- * yet succeeded.
- */
- if (c->c2.context_auth != CAS_SUCCEEDED)
- c->c2.buf.len = 0;
-#endif
-#endif /* USE_SSL */
-
- /* authenticate and decrypt the incoming packet */
- decrypt_status = openvpn_decrypt (&c->c2.buf, c->c2.buffers->decrypt_buf, &c->c2.crypto_options, &c->c2.frame);
-
- if (!decrypt_status && link_socket_connection_oriented (c->c2.link_socket))
- {
- /* decryption errors are fatal in TCP mode */
- c->sig->signal_received = SIGUSR1; /* SOFT-SIGUSR1 -- decryption error in TCP mode */
- c->sig->signal_text = "decryption-error";
- msg (D_STREAM_ERRORS, "Fatal decryption error (process_incoming_link), restarting");
- goto done;
- }
-
-#endif /* USE_CRYPTO */
-
-#ifdef ENABLE_FRAGMENT
- if (c->c2.fragment)
- fragment_incoming (c->c2.fragment, &c->c2.buf, &c->c2.frame_fragment);
-#endif
-
-#ifdef USE_LZO
- /* decompress the incoming packet */
- if (lzo_defined (&c->c2.lzo_compwork))
- lzo_decompress (&c->c2.buf, c->c2.buffers->lzo_decompress_buf, &c->c2.lzo_compwork, &c->c2.frame);
-#endif
-
-#ifdef PACKET_TRUNCATION_CHECK
- /* if (c->c2.buf.len > 1) --c->c2.buf.len; */
- ipv4_packet_size_verify (BPTR (&c->c2.buf),
- BLEN (&c->c2.buf),
- TUNNEL_TYPE (c->c1.tuntap),
- "POST_DECRYPT",
- &c->c2.n_trunc_post_decrypt);
-#endif
-
- /*
- * Set our "official" outgoing address, since
- * if buf.len is non-zero, we know the packet
- * authenticated. In TLS mode we do nothing
- * because TLS mode takes care of source address
- * authentication.
- *
- * Also, update the persisted version of our packet-id.
- */
- if (!TLS_MODE (c))
- link_socket_set_outgoing_addr (&c->c2.buf, lsi, &c->c2.from, NULL, c->c2.es);
-
- /* reset packet received timer */
- if (c->options.ping_rec_timeout && c->c2.buf.len > 0)
- event_timeout_reset (&c->c2.ping_rec_interval);
-
- /* increment authenticated receive byte count */
- if (c->c2.buf.len > 0)
- {
- c->c2.link_read_bytes_auth += c->c2.buf.len;
- c->c2.max_recv_size_local = max_int (c->c2.original_recv_size, c->c2.max_recv_size_local);
- }
-
- /* Did we just receive an openvpn ping packet? */
- if (is_ping_msg (&c->c2.buf))
- {
- dmsg (D_PING, "RECEIVED PING PACKET");
- c->c2.buf.len = 0; /* drop packet */
- }
-
-#ifdef ENABLE_OCC
- /* Did we just receive an OCC packet? */
- if (is_occ_msg (&c->c2.buf))
- process_received_occ_msg (c);
-#endif
-
- buffer_turnover (orig_buf, &c->c2.to_tun, &c->c2.buf, &c->c2.buffers->read_link_buf);
-
- /* to_tun defined + unopened tuntap can cause deadlock */
- if (!tuntap_defined (c->c1.tuntap))
- c->c2.to_tun.len = 0;
- }
- else
- {
- buf_reset (&c->c2.to_tun);
- }
- done:
- perf_pop ();
- gc_free (&gc);
-}
-
-/*
- * Output: c->c2.buf
- */
-
-void
-read_incoming_tun (struct context *c)
-{
- /*
- * Setup for read() call on TUN/TAP device.
- */
- /*ASSERT (!c->c2.to_link.len);*/
-
- perf_push (PERF_READ_IN_TUN);
-
- c->c2.buf = c->c2.buffers->read_tun_buf;
-#ifdef TUN_PASS_BUFFER
- read_tun_buffered (c->c1.tuntap, &c->c2.buf, MAX_RW_SIZE_TUN (&c->c2.frame));
-#else
- ASSERT (buf_init (&c->c2.buf, FRAME_HEADROOM (&c->c2.frame)));
- ASSERT (buf_safe (&c->c2.buf, MAX_RW_SIZE_TUN (&c->c2.frame)));
- c->c2.buf.len = read_tun (c->c1.tuntap, BPTR (&c->c2.buf), MAX_RW_SIZE_TUN (&c->c2.frame));
-#endif
-
-#ifdef PACKET_TRUNCATION_CHECK
- ipv4_packet_size_verify (BPTR (&c->c2.buf),
- BLEN (&c->c2.buf),
- TUNNEL_TYPE (c->c1.tuntap),
- "READ_TUN",
- &c->c2.n_trunc_tun_read);
-#endif
-
- /* Was TUN/TAP interface stopped? */
- if (tuntap_stop (c->c2.buf.len))
- {
- c->sig->signal_received = SIGTERM;
- c->sig->signal_text = "tun-stop";
- msg (M_INFO, "TUN/TAP interface has been stopped, exiting");
- perf_pop ();
- return;
- }
-
- /* Check the status return from read() */
- check_status (c->c2.buf.len, "read from TUN/TAP", NULL, c->c1.tuntap);
-
- perf_pop ();
-}
-
-/*
- * Input: c->c2.buf
- * Output: c->c2.to_link
- */
-
-void
-process_incoming_tun (struct context *c)
-{
- struct gc_arena gc = gc_new ();
-
- perf_push (PERF_PROC_IN_TUN);
-
- if (c->c2.buf.len > 0)
- c->c2.tun_read_bytes += c->c2.buf.len;
-
-#ifdef LOG_RW
- if (c->c2.log_rw && c->c2.buf.len > 0)
- fprintf (stderr, "r");
-#endif
-
- /* Show packet content */
- dmsg (D_TUN_RW, "TUN READ [%d]", BLEN (&c->c2.buf));
-
- if (c->c2.buf.len > 0)
- {
- /*
- * The --passtos and --mssfix options require
- * us to examine the IPv4 header.
- */
- process_ipv4_header (c, PIPV4_PASSTOS|PIPV4_MSSFIX, &c->c2.buf);
-
-#ifdef PACKET_TRUNCATION_CHECK
- /* if (c->c2.buf.len > 1) --c->c2.buf.len; */
- ipv4_packet_size_verify (BPTR (&c->c2.buf),
- BLEN (&c->c2.buf),
- TUNNEL_TYPE (c->c1.tuntap),
- "PRE_ENCRYPT",
- &c->c2.n_trunc_pre_encrypt);
-#endif
-
- encrypt_sign (c, true);
- }
- else
- {
- buf_reset (&c->c2.to_link);
- }
- perf_pop ();
- gc_free (&gc);
-}
-
-void
-process_ipv4_header (struct context *c, unsigned int flags, struct buffer *buf)
-{
- if (!c->options.mssfix)
- flags &= ~PIPV4_MSSFIX;
-#if PASSTOS_CAPABILITY
- if (!c->options.passtos)
- flags &= ~PIPV4_PASSTOS;
-#endif
- if (!c->options.route_gateway_via_dhcp || !route_list_default_gateway_needed (c->c1.route_list))
- flags &= ~PIPV4_EXTRACT_DHCP_ROUTER;
-
- if (buf->len > 0)
- {
- /*
- * The --passtos and --mssfix options require
- * us to examine the IPv4 header.
- */
-#if PASSTOS_CAPABILITY
- if (flags & (PIPV4_PASSTOS|PIPV4_MSSFIX))
-#else
- if (flags & PIPV4_MSSFIX)
-#endif
- {
- struct buffer ipbuf = *buf;
- if (is_ipv4 (TUNNEL_TYPE (c->c1.tuntap), &ipbuf))
- {
-#if PASSTOS_CAPABILITY
- /* extract TOS from IP header */
- if (flags & PIPV4_PASSTOS)
- link_socket_extract_tos (c->c2.link_socket, &ipbuf);
-#endif
-
- /* possibly alter the TCP MSS */
- if (flags & PIPV4_MSSFIX)
- mss_fixup (&ipbuf, MTU_TO_MSS (TUN_MTU_SIZE_DYNAMIC (&c->c2.frame)));
-
- /* possibly extract a DHCP router message */
- if (flags & PIPV4_EXTRACT_DHCP_ROUTER)
- {
- const in_addr_t dhcp_router = dhcp_extract_router_msg (&ipbuf);
- if (dhcp_router)
- route_list_add_default_gateway (c->c1.route_list, c->c2.es, dhcp_router);
- }
- }
- }
- }
-}
-
-/*
- * Input: c->c2.to_link
- */
-
-void
-process_outgoing_link (struct context *c)
-{
- struct gc_arena gc = gc_new ();
-
- perf_push (PERF_PROC_OUT_LINK);
-
- if (c->c2.to_link.len > 0 && c->c2.to_link.len <= EXPANDED_SIZE (&c->c2.frame))
- {
- /*
- * Setup for call to send/sendto which will send
- * packet to remote over the TCP/UDP port.
- */
- int size = 0;
- ASSERT (link_socket_actual_defined (c->c2.to_link_addr));
-
-#ifdef ENABLE_DEBUG
- /* In gremlin-test mode, we may choose to drop this packet */
- if (!c->options.gremlin || ask_gremlin (c->options.gremlin))
-#endif
- {
- /*
- * Let the traffic shaper know how many bytes
- * we wrote.
- */
-#ifdef HAVE_GETTIMEOFDAY
- if (c->options.shaper)
- shaper_wrote_bytes (&c->c2.shaper, BLEN (&c->c2.to_link)
- + datagram_overhead (c->options.ce.proto));
-#endif
- /*
- * Let the pinger know that we sent a packet.
- */
- if (c->options.ping_send_timeout)
- event_timeout_reset (&c->c2.ping_send_interval);
-
-#if PASSTOS_CAPABILITY
- /* Set TOS */
- link_socket_set_tos (c->c2.link_socket);
-#endif
-
- /* Log packet send */
-#ifdef LOG_RW
- if (c->c2.log_rw)
- fprintf (stderr, "W");
-#endif
- msg (D_LINK_RW, "%s WRITE [%d] to %s: %s",
- proto2ascii (c->c2.link_socket->info.proto, true),
- BLEN (&c->c2.to_link),
- print_link_socket_actual (c->c2.to_link_addr, &gc),
- PROTO_DUMP (&c->c2.to_link, &gc));
-
- /* Packet send complexified by possible Socks5 usage */
- {
- struct link_socket_actual *to_addr = c->c2.to_link_addr;
-#ifdef ENABLE_SOCKS
- int size_delta = 0;
-#endif
-
-#ifdef ENABLE_SOCKS
- /* If Socks5 over UDP, prepend header */
- socks_preprocess_outgoing_link (c, &to_addr, &size_delta);
-#endif
- /* Send packet */
- size = link_socket_write (c->c2.link_socket,
- &c->c2.to_link,
- to_addr);
-
-#ifdef ENABLE_SOCKS
- /* Undo effect of prepend */
- link_socket_write_post_size_adjust (&size, size_delta, &c->c2.to_link);
-#endif
- }
-
- if (size > 0)
- {
- c->c2.max_send_size_local = max_int (size, c->c2.max_send_size_local);
- c->c2.link_write_bytes += size;
- link_write_bytes_global += size;
-#ifdef ENABLE_MANAGEMENT
- if (management)
- {
- management_bytes_out (management, size);
-#ifdef MANAGEMENT_DEF_AUTH
- management_bytes_server (management, &c->c2.link_read_bytes, &c->c2.link_write_bytes, &c->c2.mda_context);
-#endif
- }
-#endif
- }
- }
-
- /* Check return status */
- check_status (size, "write", c->c2.link_socket, NULL);
-
- if (size > 0)
- {
- /* Did we write a different size packet than we intended? */
- if (size != BLEN (&c->c2.to_link))
- msg (D_LINK_ERRORS,
- "TCP/UDP packet was truncated/expanded on write to %s (tried=%d,actual=%d)",
- print_link_socket_actual (c->c2.to_link_addr, &gc),
- BLEN (&c->c2.to_link),
- size);
- }
-
- /* if not a ping/control message, indicate activity regarding --inactive parameter */
- if (c->c2.buf.len > 0 )
- register_activity (c, size);
- }
- else
- {
- if (c->c2.to_link.len > 0)
- msg (D_LINK_ERRORS, "TCP/UDP packet too large on write to %s (tried=%d,max=%d)",
- print_link_socket_actual (c->c2.to_link_addr, &gc),
- c->c2.to_link.len,
- EXPANDED_SIZE (&c->c2.frame));
- }
-
- buf_reset (&c->c2.to_link);
-
- perf_pop ();
- gc_free (&gc);
-}
-
-/*
- * Input: c->c2.to_tun
- */
-
-void
-process_outgoing_tun (struct context *c)
-{
- struct gc_arena gc = gc_new ();
-
- /*
- * Set up for write() call to TUN/TAP
- * device.
- */
- if (c->c2.to_tun.len <= 0)
- return;
-
- perf_push (PERF_PROC_OUT_TUN);
-
- /*
- * The --mssfix option requires
- * us to examine the IPv4 header.
- */
- process_ipv4_header (c, PIPV4_MSSFIX|PIPV4_EXTRACT_DHCP_ROUTER|PIPV4_OUTGOING, &c->c2.to_tun);
-
- if (c->c2.to_tun.len <= MAX_RW_SIZE_TUN (&c->c2.frame))
- {
- /*
- * Write to TUN/TAP device.
- */
- int size;
-
-#ifdef LOG_RW
- if (c->c2.log_rw)
- fprintf (stderr, "w");
-#endif
- dmsg (D_TUN_RW, "TUN WRITE [%d]", BLEN (&c->c2.to_tun));
-
-#ifdef PACKET_TRUNCATION_CHECK
- ipv4_packet_size_verify (BPTR (&c->c2.to_tun),
- BLEN (&c->c2.to_tun),
- TUNNEL_TYPE (c->c1.tuntap),
- "WRITE_TUN",
- &c->c2.n_trunc_tun_write);
-#endif
-
-#ifdef TUN_PASS_BUFFER
- size = write_tun_buffered (c->c1.tuntap, &c->c2.to_tun);
-#else
- size = write_tun (c->c1.tuntap, BPTR (&c->c2.to_tun), BLEN (&c->c2.to_tun));
-#endif
-
- if (size > 0)
- c->c2.tun_write_bytes += size;
- check_status (size, "write to TUN/TAP", NULL, c->c1.tuntap);
-
- /* check written packet size */
- if (size > 0)
- {
- /* Did we write a different size packet than we intended? */
- if (size != BLEN (&c->c2.to_tun))
- msg (D_LINK_ERRORS,
- "TUN/TAP packet was destructively fragmented on write to %s (tried=%d,actual=%d)",
- c->c1.tuntap->actual_name,
- BLEN (&c->c2.to_tun),
- size);
-
- /* indicate activity regarding --inactive parameter */
- register_activity (c, size);
- }
- }
- else
- {
- /*
- * This should never happen, probably indicates some kind
- * of MTU mismatch.
- */
- msg (D_LINK_ERRORS, "tun packet too large on write (tried=%d,max=%d)",
- c->c2.to_tun.len,
- MAX_RW_SIZE_TUN (&c->c2.frame));
- }
-
- buf_reset (&c->c2.to_tun);
-
- perf_pop ();
- gc_free (&gc);
-}
-
-void
-pre_select (struct context *c)
-{
- /* make sure current time (now) is updated on function entry */
-
- /*
- * Start with an effectively infinite timeout, then let it
- * reduce to a timeout that reflects the component which
- * needs the earliest service.
- */
- c->c2.timeval.tv_sec = BIG_TIMEOUT;
- c->c2.timeval.tv_usec = 0;
-
-#if defined(WIN32)
- if (check_debug_level (D_TAP_WIN32_DEBUG))
- {
- c->c2.timeval.tv_sec = 1;
- if (tuntap_defined (c->c1.tuntap))
- tun_show_debug (c->c1.tuntap);
- }
-#endif
-
- /* check coarse timers? */
- check_coarse_timers (c);
- if (c->sig->signal_received)
- return;
-
- /* Does TLS need service? */
- check_tls (c);
-
- /* In certain cases, TLS errors will require a restart */
- check_tls_errors (c);
- if (c->sig->signal_received)
- return;
-
- /* check for incoming configuration info on the control channel */
- check_incoming_control_channel (c);
-
-#ifdef ENABLE_OCC
- /* Should we send an OCC message? */
- check_send_occ_msg (c);
-#endif
-
-#ifdef ENABLE_FRAGMENT
- /* Should we deliver a datagram fragment to remote? */
- check_fragment (c);
-#endif
-
- /* Update random component of timeout */
- check_timeout_random_component (c);
-}
-
-/*
- * Wait for I/O events. Used for both TCP & UDP sockets
- * in point-to-point mode and for UDP sockets in
- * point-to-multipoint mode.
- */
-
-void
-io_wait_dowork (struct context *c, const unsigned int flags)
-{
- unsigned int socket = 0;
- unsigned int tuntap = 0;
- struct event_set_return esr[4];
-
- /* These shifts all depend on EVENT_READ and EVENT_WRITE */
- static int socket_shift = 0; /* depends on SOCKET_READ and SOCKET_WRITE */
- static int tun_shift = 2; /* depends on TUN_READ and TUN_WRITE */
- static int err_shift = 4; /* depends on ES_ERROR */
-#ifdef ENABLE_MANAGEMENT
- static int management_shift = 6; /* depends on MANAGEMENT_READ and MANAGEMENT_WRITE */
-#endif
-
- /*
- * Decide what kind of events we want to wait for.
- */
- event_reset (c->c2.event_set);
-
- /*
- * On win32 we use the keyboard or an event object as a source
- * of asynchronous signals.
- */
- if (flags & IOW_WAIT_SIGNAL)
- wait_signal (c->c2.event_set, (void*)&err_shift);
-
- /*
- * If outgoing data (for TCP/UDP port) pending, wait for ready-to-send
- * status from TCP/UDP port. Otherwise, wait for incoming data on
- * TUN/TAP device.
- */
- if (flags & IOW_TO_LINK)
- {
- if (flags & IOW_SHAPER)
- {
- /*
- * If sending this packet would put us over our traffic shaping
- * quota, don't send -- instead compute the delay we must wait
- * until it will be OK to send the packet.
- */
-#ifdef HAVE_GETTIMEOFDAY
- int delay = 0;
-
- /* set traffic shaping delay in microseconds */
- if (c->options.shaper)
- delay = max_int (delay, shaper_delay (&c->c2.shaper));
-
- if (delay < 1000)
- {
- socket |= EVENT_WRITE;
- }
- else
- {
- shaper_soonest_event (&c->c2.timeval, delay);
- }
-#else /* HAVE_GETTIMEOFDAY */
- socket |= EVENT_WRITE;
-#endif /* HAVE_GETTIMEOFDAY */
- }
- else
- {
- socket |= EVENT_WRITE;
- }
- }
- else if (!((flags & IOW_FRAG) && TO_LINK_FRAG (c)))
- {
- if (flags & IOW_READ_TUN)
- tuntap |= EVENT_READ;
- }
-
- /*
- * If outgoing data (for TUN/TAP device) pending, wait for ready-to-send status
- * from device. Otherwise, wait for incoming data on TCP/UDP port.
- */
- if (flags & IOW_TO_TUN)
- {
- tuntap |= EVENT_WRITE;
- }
- else
- {
- if (flags & IOW_READ_LINK)
- socket |= EVENT_READ;
- }
-
- /*
- * outgoing bcast buffer waiting to be sent?
- */
- if (flags & IOW_MBUF)
- socket |= EVENT_WRITE;
-
- /*
- * Force wait on TUN input, even if also waiting on TCP/UDP output
- */
- if (flags & IOW_READ_TUN_FORCE)
- tuntap |= EVENT_READ;
-
- /*
- * Configure event wait based on socket, tuntap flags.
- */
- socket_set (c->c2.link_socket, c->c2.event_set, socket, (void*)&socket_shift, NULL);
- tun_set (c->c1.tuntap, c->c2.event_set, tuntap, (void*)&tun_shift, NULL);
-
-#ifdef ENABLE_MANAGEMENT
- if (management)
- management_socket_set (management, c->c2.event_set, (void*)&management_shift, NULL);
-#endif
-
- /*
- * Possible scenarios:
- * (1) tcp/udp port has data available to read
- * (2) tcp/udp port is ready to accept more data to write
- * (3) tun dev has data available to read
- * (4) tun dev is ready to accept more data to write
- * (5) we received a signal (handler sets signal_received)
- * (6) timeout (tv) expired
- */
-
- c->c2.event_set_status = ES_ERROR;
-
- if (!c->sig->signal_received)
- {
- if (!(flags & IOW_CHECK_RESIDUAL) || !socket_read_residual (c->c2.link_socket))
- {
- int status;
-
-#ifdef ENABLE_DEBUG
- if (check_debug_level (D_EVENT_WAIT))
- show_wait_status (c);
-#endif
-
- /*
- * Wait for something to happen.
- */
- status = event_wait (c->c2.event_set, &c->c2.timeval, esr, SIZE(esr));
-
- check_status (status, "event_wait", NULL, NULL);
-
- if (status > 0)
- {
- int i;
- c->c2.event_set_status = 0;
- for (i = 0; i < status; ++i)
- {
- const struct event_set_return *e = &esr[i];
- c->c2.event_set_status |= ((e->rwflags & 3) << *((int*)e->arg));
- }
- }
- else if (status == 0)
- {
- c->c2.event_set_status = ES_TIMEOUT;
- }
- }
- else
- {
- c->c2.event_set_status = SOCKET_READ;
- }
- }
-
- /* 'now' should always be a reasonably up-to-date timestamp */
- update_time ();
-
- /* set signal_received if a signal was received */
- if (c->c2.event_set_status & ES_ERROR)
- get_signal (&c->sig->signal_received);
-
- dmsg (D_EVENT_WAIT, "I/O WAIT status=0x%04x", c->c2.event_set_status);
-}
-
-void
-process_io (struct context *c)
-{
- const unsigned int status = c->c2.event_set_status;
-
-#ifdef ENABLE_MANAGEMENT
- if (status & (MANAGEMENT_READ|MANAGEMENT_WRITE))
- {
- ASSERT (management);
- management_io (management);
- }
-#endif
-
- /* TCP/UDP port ready to accept write */
- if (status & SOCKET_WRITE)
- {
- process_outgoing_link (c);
- }
- /* TUN device ready to accept write */
- else if (status & TUN_WRITE)
- {
- process_outgoing_tun (c);
- }
- /* Incoming data on TCP/UDP port */
- else if (status & SOCKET_READ)
- {
- read_incoming_link (c);
- if (!IS_SIG (c))
- process_incoming_link (c);
- }
- /* Incoming data on TUN device */
- else if (status & TUN_READ)
- {
- read_incoming_tun (c);
- if (!IS_SIG (c))
- process_incoming_tun (c);
- }
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 19:51:27 +0000