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-rw-r--r--mtcp.c718
1 files changed, 0 insertions, 718 deletions
diff --git a/mtcp.c b/mtcp.c
deleted file mode 100644
index 314aa44..0000000
--- a/mtcp.c
+++ /dev/null
@@ -1,718 +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"
-
-#if P2MP_SERVER
-
-#include "multi.h"
-#include "forward-inline.h"
-
-#include "memdbg.h"
-
-/*
- * TCP States
- */
-#define TA_UNDEF 0
-#define TA_SOCKET_READ 1
-#define TA_SOCKET_READ_RESIDUAL 2
-#define TA_SOCKET_WRITE 3
-#define TA_SOCKET_WRITE_READY 4
-#define TA_SOCKET_WRITE_DEFERRED 5
-#define TA_TUN_READ 6
-#define TA_TUN_WRITE 7
-#define TA_INITIAL 8
-#define TA_TIMEOUT 9
-#define TA_TUN_WRITE_TIMEOUT 10
-
-/*
- * Special tags passed to event.[ch] functions
- */
-#define MTCP_SOCKET ((void*)1)
-#define MTCP_TUN ((void*)2)
-#define MTCP_SIG ((void*)3) /* Only on Windows */
-#ifdef ENABLE_MANAGEMENT
-# define MTCP_MANAGEMENT ((void*)4)
-#endif
-
-#define MTCP_N ((void*)16) /* upper bound on MTCP_x */
-
-struct ta_iow_flags
-{
- unsigned int flags;
- unsigned int ret;
- unsigned int tun;
- unsigned int sock;
-};
-
-static const char *
-pract (int action)
-{
- switch (action)
- {
- case TA_UNDEF:
- return "TA_UNDEF";
- case TA_SOCKET_READ:
- return "TA_SOCKET_READ";
- case TA_SOCKET_READ_RESIDUAL:
- return "TA_SOCKET_READ_RESIDUAL";
- case TA_SOCKET_WRITE:
- return "TA_SOCKET_WRITE";
- case TA_SOCKET_WRITE_READY:
- return "TA_SOCKET_WRITE_READY";
- case TA_SOCKET_WRITE_DEFERRED:
- return "TA_SOCKET_WRITE_DEFERRED";
- case TA_TUN_READ:
- return "TA_TUN_READ";
- case TA_TUN_WRITE:
- return "TA_TUN_WRITE";
- case TA_INITIAL:
- return "TA_INITIAL";
- case TA_TIMEOUT:
- return "TA_TIMEOUT";
- case TA_TUN_WRITE_TIMEOUT:
- return "TA_TUN_WRITE_TIMEOUT";
- default:
- return "?";
- }
-}
-
-static struct multi_instance *
-multi_create_instance_tcp (struct multi_context *m)
-{
- struct gc_arena gc = gc_new ();
- struct multi_instance *mi = NULL;
- struct hash *hash = m->hash;
-
- mi = multi_create_instance (m, NULL);
- if (mi)
- {
- struct hash_element *he;
- const uint32_t hv = hash_value (hash, &mi->real);
- struct hash_bucket *bucket = hash_bucket (hash, hv);
-
- he = hash_lookup_fast (hash, bucket, &mi->real, hv);
-
- if (he)
- {
- struct multi_instance *oldmi = (struct multi_instance *) he->value;
- msg (D_MULTI_LOW, "MULTI TCP: new incoming client address matches existing client address -- new client takes precedence");
- oldmi->did_real_hash = false;
- multi_close_instance (m, oldmi, false);
- he->key = &mi->real;
- he->value = mi;
- }
- else
- hash_add_fast (hash, bucket, &mi->real, hv, mi);
-
- mi->did_real_hash = true;
- }
-
-#ifdef ENABLE_DEBUG
- if (mi)
- dmsg (D_MULTI_DEBUG, "MULTI TCP: instance added: %s", mroute_addr_print (&mi->real, &gc));
- else
- dmsg (D_MULTI_DEBUG, "MULTI TCP: new client instance failed");
-#endif
-
- gc_free (&gc);
- ASSERT (!(mi && mi->halt));
- return mi;
-}
-
-bool
-multi_tcp_instance_specific_init (struct multi_context *m, struct multi_instance *mi)
-{
- /* buffer for queued TCP socket output packets */
- mi->tcp_link_out_deferred = mbuf_init (m->top.options.n_bcast_buf);
-
- ASSERT (mi->context.c2.link_socket);
- ASSERT (mi->context.c2.link_socket->info.lsa);
- ASSERT (mi->context.c2.link_socket->mode == LS_MODE_TCP_ACCEPT_FROM);
- if (!mroute_extract_openvpn_sockaddr (&mi->real, &mi->context.c2.link_socket->info.lsa->actual.dest, true))
- {
- msg (D_MULTI_ERRORS, "MULTI TCP: TCP client address is undefined");
- return false;
- }
- return true;
-}
-
-void
-multi_tcp_instance_specific_free (struct multi_instance *mi)
-{
- mbuf_free (mi->tcp_link_out_deferred);
-}
-
-struct multi_tcp *
-multi_tcp_init (int maxevents, int *maxclients)
-{
- struct multi_tcp *mtcp;
- const int extra_events = BASE_N_EVENTS;
-
- ASSERT (maxevents >= 1);
- ASSERT (maxclients);
-
- ALLOC_OBJ_CLEAR (mtcp, struct multi_tcp);
- mtcp->maxevents = maxevents + extra_events;
- mtcp->es = event_set_init (&mtcp->maxevents, 0);
- wait_signal (mtcp->es, MTCP_SIG);
- ALLOC_ARRAY (mtcp->esr, struct event_set_return, mtcp->maxevents);
- *maxclients = max_int (min_int (mtcp->maxevents - extra_events, *maxclients), 1);
- msg (D_MULTI_LOW, "MULTI: TCP INIT maxclients=%d maxevents=%d", *maxclients, mtcp->maxevents);
- return mtcp;
-}
-
-void
-multi_tcp_delete_event (struct multi_tcp *mtcp, event_t event)
-{
- if (mtcp && mtcp->es)
- event_del (mtcp->es, event);
-}
-
-void
-multi_tcp_free (struct multi_tcp *mtcp)
-{
- if (mtcp)
- {
- event_free (mtcp->es);
- if (mtcp->esr)
- free (mtcp->esr);
- free (mtcp);
- }
-}
-
-void
-multi_tcp_dereference_instance (struct multi_tcp *mtcp, struct multi_instance *mi)
-{
- struct link_socket *ls = mi->context.c2.link_socket;
- if (ls && mi->socket_set_called)
- event_del (mtcp->es, socket_event_handle (ls));
- mtcp->n_esr = 0;
-}
-
-static inline void
-multi_tcp_set_global_rw_flags (struct multi_context *m, struct multi_instance *mi)
-{
- if (mi)
- {
- mi->socket_set_called = true;
- socket_set (mi->context.c2.link_socket,
- m->mtcp->es,
- mbuf_defined (mi->tcp_link_out_deferred) ? EVENT_WRITE : EVENT_READ,
- mi,
- &mi->tcp_rwflags);
- }
-}
-
-static inline int
-multi_tcp_wait (const struct context *c,
- struct multi_tcp *mtcp)
-{
- int status;
- socket_set_listen_persistent (c->c2.link_socket, mtcp->es, MTCP_SOCKET);
- tun_set (c->c1.tuntap, mtcp->es, EVENT_READ, MTCP_TUN, &mtcp->tun_rwflags);
-#ifdef ENABLE_MANAGEMENT
- if (management)
- management_socket_set (management, mtcp->es, MTCP_MANAGEMENT, &mtcp->management_persist_flags);
-#endif
- status = event_wait (mtcp->es, &c->c2.timeval, mtcp->esr, mtcp->maxevents);
- update_time ();
- mtcp->n_esr = 0;
- if (status > 0)
- mtcp->n_esr = status;
- return status;
-}
-
-static inline struct context *
-multi_tcp_context (struct multi_context *m, struct multi_instance *mi)
-{
- if (mi)
- return &mi->context;
- else
- return &m->top;
-}
-
-static bool
-multi_tcp_process_outgoing_link_ready (struct multi_context *m, struct multi_instance *mi, const unsigned int mpp_flags)
-{
- struct mbuf_item item;
- bool ret = true;
- ASSERT (mi);
-
- /* extract from queue */
- if (mbuf_extract_item (mi->tcp_link_out_deferred, &item)) /* ciphertext IP packet */
- {
- dmsg (D_MULTI_TCP, "MULTI TCP: transmitting previously deferred packet");
-
- ASSERT (mi == item.instance);
- mi->context.c2.to_link = item.buffer->buf;
- ret = multi_process_outgoing_link_dowork (m, mi, mpp_flags);
- if (!ret)
- mi = NULL;
- mbuf_free_buf (item.buffer);
- }
- return ret;
-}
-
-static bool
-multi_tcp_process_outgoing_link (struct multi_context *m, bool defer, const unsigned int mpp_flags)
-{
- struct multi_instance *mi = multi_process_outgoing_link_pre (m);
- bool ret = true;
-
- if (mi)
- {
- if (defer || mbuf_defined (mi->tcp_link_out_deferred))
- {
- /* save to queue */
- struct buffer *buf = &mi->context.c2.to_link;
- if (BLEN (buf) > 0)
- {
- struct mbuf_buffer *mb = mbuf_alloc_buf (buf);
- struct mbuf_item item;
-
- set_prefix (mi);
- dmsg (D_MULTI_TCP, "MULTI TCP: queuing deferred packet");
- item.buffer = mb;
- item.instance = mi;
- mbuf_add_item (mi->tcp_link_out_deferred, &item);
- mbuf_free_buf (mb);
- buf_reset (buf);
- ret = multi_process_post (m, mi, mpp_flags);
- if (!ret)
- mi = NULL;
- clear_prefix ();
- }
- }
- else
- {
- ret = multi_process_outgoing_link_dowork (m, mi, mpp_flags);
- if (!ret)
- mi = NULL;
- }
- }
- return ret;
-}
-
-static int
-multi_tcp_wait_lite (struct multi_context *m, struct multi_instance *mi, const int action, bool *tun_input_pending)
-{
- struct context *c = multi_tcp_context (m, mi);
- unsigned int looking_for = 0;
-
- dmsg (D_MULTI_DEBUG, "MULTI TCP: multi_tcp_wait_lite a=%s mi=" ptr_format,
- pract(action),
- (ptr_type)mi);
-
- tv_clear (&c->c2.timeval); /* ZERO-TIMEOUT */
-
- switch (action)
- {
- case TA_TUN_READ:
- looking_for = TUN_READ;
- tun_input_pending = NULL;
- io_wait (c, IOW_READ_TUN);
- break;
- case TA_SOCKET_READ:
- looking_for = SOCKET_READ;
- tun_input_pending = NULL;
- io_wait (c, IOW_READ_LINK);
- break;
- case TA_TUN_WRITE:
- looking_for = TUN_WRITE;
- tun_input_pending = NULL;
- c->c2.timeval.tv_sec = 1; /* For some reason, the Linux 2.2 TUN/TAP driver hits this timeout */
- perf_push (PERF_PROC_OUT_TUN_MTCP);
- io_wait (c, IOW_TO_TUN);
- perf_pop ();
- break;
- case TA_SOCKET_WRITE:
- looking_for = SOCKET_WRITE;
- io_wait (c, IOW_TO_LINK|IOW_READ_TUN_FORCE);
- break;
- default:
- msg (M_FATAL, "MULTI TCP: multi_tcp_wait_lite, unhandled action=%d", action);
- }
-
- if (tun_input_pending && (c->c2.event_set_status & TUN_READ))
- *tun_input_pending = true;
-
- if (c->c2.event_set_status & looking_for)
- {
- return action;
- }
- else
- {
- switch (action)
- {
- /* TCP socket output buffer is full */
- case TA_SOCKET_WRITE:
- return TA_SOCKET_WRITE_DEFERRED;
-
- /* TUN device timed out on accepting write */
- case TA_TUN_WRITE:
- return TA_TUN_WRITE_TIMEOUT;
- }
-
- return TA_UNDEF;
- }
-}
-
-static struct multi_instance *
-multi_tcp_dispatch (struct multi_context *m, struct multi_instance *mi, const int action)
-{
- const unsigned int mpp_flags = MPP_PRE_SELECT|MPP_RECORD_TOUCH;
- struct multi_instance *touched = mi;
- m->mpp_touched = &touched;
-
- dmsg (D_MULTI_DEBUG, "MULTI TCP: multi_tcp_dispatch a=%s mi=" ptr_format,
- pract(action),
- (ptr_type)mi);
-
- switch (action)
- {
- case TA_TUN_READ:
- read_incoming_tun (&m->top);
- if (!IS_SIG (&m->top))
- multi_process_incoming_tun (m, mpp_flags);
- break;
- case TA_SOCKET_READ:
- case TA_SOCKET_READ_RESIDUAL:
- ASSERT (mi);
- ASSERT (mi->context.c2.link_socket);
- set_prefix (mi);
- read_incoming_link (&mi->context);
- clear_prefix ();
- if (!IS_SIG (&mi->context))
- {
- multi_process_incoming_link (m, mi, mpp_flags);
- if (!IS_SIG (&mi->context))
- stream_buf_read_setup (mi->context.c2.link_socket);
- }
- break;
- case TA_TIMEOUT:
- multi_process_timeout (m, mpp_flags);
- break;
- case TA_TUN_WRITE:
- multi_process_outgoing_tun (m, mpp_flags);
- break;
- case TA_TUN_WRITE_TIMEOUT:
- multi_process_drop_outgoing_tun (m, mpp_flags);
- break;
- case TA_SOCKET_WRITE_READY:
- ASSERT (mi);
- multi_tcp_process_outgoing_link_ready (m, mi, mpp_flags);
- break;
- case TA_SOCKET_WRITE:
- multi_tcp_process_outgoing_link (m, false, mpp_flags);
- break;
- case TA_SOCKET_WRITE_DEFERRED:
- multi_tcp_process_outgoing_link (m, true, mpp_flags);
- break;
- case TA_INITIAL:
- ASSERT (mi);
- multi_tcp_set_global_rw_flags (m, mi);
- multi_process_post (m, mi, mpp_flags);
- break;
- default:
- msg (M_FATAL, "MULTI TCP: multi_tcp_dispatch, unhandled action=%d", action);
- }
-
- m->mpp_touched = NULL;
- return touched;
-}
-
-int
-multi_tcp_post (struct multi_context *m, struct multi_instance *mi, const int action)
-{
- struct context *c = multi_tcp_context (m, mi);
- int newaction = TA_UNDEF;
-
-# define MTP_NONE 0
-# define MTP_TUN_OUT (1<<0)
-# define MTP_LINK_OUT (1<<1)
- unsigned int flags = MTP_NONE;
-
- if (TUN_OUT(c))
- flags |= MTP_TUN_OUT;
- if (LINK_OUT(c))
- flags |= MTP_LINK_OUT;
-
- switch (flags)
- {
- case MTP_TUN_OUT|MTP_LINK_OUT:
- case MTP_TUN_OUT:
- newaction = TA_TUN_WRITE;
- break;
- case MTP_LINK_OUT:
- newaction = TA_SOCKET_WRITE;
- break;
- case MTP_NONE:
- if (mi && socket_read_residual (c->c2.link_socket))
- newaction = TA_SOCKET_READ_RESIDUAL;
- else
- multi_tcp_set_global_rw_flags (m, mi);
- break;
- default:
- {
- struct gc_arena gc = gc_new ();
- msg (M_FATAL, "MULTI TCP: multi_tcp_post bad state, mi=%s flags=%d",
- multi_instance_string (mi, false, &gc),
- flags);
- gc_free (&gc);
- break;
- }
- }
-
- dmsg (D_MULTI_DEBUG, "MULTI TCP: multi_tcp_post %s -> %s",
- pract(action),
- pract(newaction));
-
- return newaction;
-}
-
-static void
-multi_tcp_action (struct multi_context *m, struct multi_instance *mi, int action, bool poll)
-{
- bool tun_input_pending = false;
-
- do {
- dmsg (D_MULTI_DEBUG, "MULTI TCP: multi_tcp_action a=%s p=%d",
- pract(action),
- poll);
-
- /*
- * If TA_SOCKET_READ_RESIDUAL, it means we still have pending
- * input packets which were read by a prior TCP recv.
- *
- * Otherwise do a "lite" wait, which means we wait with 0 timeout
- * on I/O events only related to the current instance, not
- * the big list of events.
- *
- * On our first pass, poll will be false because we already know
- * that input is available, and to call io_wait would be redundant.
- */
- if (poll && action != TA_SOCKET_READ_RESIDUAL)
- {
- const int orig_action = action;
- action = multi_tcp_wait_lite (m, mi, action, &tun_input_pending);
- if (action == TA_UNDEF)
- msg (M_FATAL, "MULTI TCP: I/O wait required blocking in multi_tcp_action, action=%d", orig_action);
- }
-
- /*
- * Dispatch the action
- */
- {
- struct multi_instance *touched = multi_tcp_dispatch (m, mi, action);
-
- /*
- * Signal received or TCP connection
- * reset by peer?
- */
- if (touched && IS_SIG (&touched->context))
- {
- if (mi == touched)
- mi = NULL;
- multi_close_instance_on_signal (m, touched);
- }
- }
-
- /*
- * If dispatch produced any pending output
- * for a particular instance, point to
- * that instance.
- */
- if (m->pending)
- mi = m->pending;
-
- /*
- * Based on the effects of the action,
- * such as generating pending output,
- * possibly transition to a new action state.
- */
- action = multi_tcp_post (m, mi, action);
-
- /*
- * If we are finished processing the original action,
- * check if we have any TUN input. If so, transition
- * our action state to processing this input.
- */
- if (tun_input_pending && action == TA_UNDEF)
- {
- action = TA_TUN_READ;
- mi = NULL;
- tun_input_pending = false;
- poll = false;
- }
- else
- poll = true;
-
- } while (action != TA_UNDEF);
-}
-
-static void
-multi_tcp_process_io (struct multi_context *m)
-{
- struct multi_tcp *mtcp = m->mtcp;
- int i;
-
- for (i = 0; i < mtcp->n_esr; ++i)
- {
- struct event_set_return *e = &mtcp->esr[i];
-
- /* incoming data for instance? */
- if (e->arg >= MTCP_N)
- {
- struct multi_instance *mi = (struct multi_instance *) e->arg;
- if (mi)
- {
- if (e->rwflags & EVENT_WRITE)
- multi_tcp_action (m, mi, TA_SOCKET_WRITE_READY, false);
- else if (e->rwflags & EVENT_READ)
- multi_tcp_action (m, mi, TA_SOCKET_READ, false);
- }
- }
- else
- {
-#ifdef ENABLE_MANAGEMENT
- if (e->arg == MTCP_MANAGEMENT)
- {
- ASSERT (management);
- management_io (management);
- }
- else
-#endif
- /* incoming data on TUN? */
- if (e->arg == MTCP_TUN)
- {
- if (e->rwflags & EVENT_WRITE)
- multi_tcp_action (m, NULL, TA_TUN_WRITE, false);
- else if (e->rwflags & EVENT_READ)
- multi_tcp_action (m, NULL, TA_TUN_READ, false);
- }
- /* new incoming TCP client attempting to connect? */
- else if (e->arg == MTCP_SOCKET)
- {
- struct multi_instance *mi;
- ASSERT (m->top.c2.link_socket);
- socket_reset_listen_persistent (m->top.c2.link_socket);
- mi = multi_create_instance_tcp (m);
- if (mi)
- multi_tcp_action (m, mi, TA_INITIAL, false);
- }
- /* signal received? */
- else if (e->arg == MTCP_SIG)
- {
- get_signal (&m->top.sig->signal_received);
- }
- }
- if (IS_SIG (&m->top))
- break;
- }
- mtcp->n_esr = 0;
-
- /*
- * Process queued mbuf packets destined for TCP socket
- */
- {
- struct multi_instance *mi;
- while (!IS_SIG (&m->top) && (mi = mbuf_peek (m->mbuf)) != NULL)
- {
- multi_tcp_action (m, mi, TA_SOCKET_WRITE, true);
- }
- }
-}
-
-/*
- * Top level event loop for single-threaded operation.
- * TCP mode.
- */
-void
-tunnel_server_tcp (struct context *top)
-{
- struct multi_context multi;
- int status;
-
- top->mode = CM_TOP;
- context_clear_2 (top);
-
- /* initialize top-tunnel instance */
- init_instance_handle_signals (top, top->es, CC_HARD_USR1_TO_HUP);
- if (IS_SIG (top))
- return;
-
- /* initialize global multi_context object */
- multi_init (&multi, top, true, MC_SINGLE_THREADED);
-
- /* initialize our cloned top object */
- multi_top_init (&multi, top, true);
-
- /* initialize management interface */
- init_management_callback_multi (&multi);
-
- /* finished with initialization */
- initialization_sequence_completed (top, ISC_SERVER); /* --mode server --proto tcp-server */
-
- /* per-packet event loop */
- while (true)
- {
- perf_push (PERF_EVENT_LOOP);
-
- /* wait on tun/socket list */
- multi_get_timeout (&multi, &multi.top.c2.timeval);
- status = multi_tcp_wait (&multi.top, multi.mtcp);
- MULTI_CHECK_SIG (&multi);
-
- /* check on status of coarse timers */
- multi_process_per_second_timers (&multi);
-
- /* timeout? */
- if (status > 0)
- {
- /* process the I/O which triggered select */
- multi_tcp_process_io (&multi);
- MULTI_CHECK_SIG (&multi);
- }
- else if (status == 0)
- {
- multi_tcp_action (&multi, NULL, TA_TIMEOUT, false);
- }
-
- perf_pop ();
- }
-
- /* shut down management interface */
- uninit_management_callback_multi (&multi);
-
- /* save ifconfig-pool */
- multi_ifconfig_pool_persist (&multi, true);
-
- /* tear down tunnel instance (unless --persist-tun) */
- multi_uninit (&multi);
- multi_top_free (&multi);
- close_instance (top);
-}
-
-#endif