Imported Upstream version 2.3_rc1

1 files changed, 291 insertions, 0 deletions

diff --git a/src/openvpn/mudp.c b/src/openvpn/mudp.c
new file mode 100644
index 0000000..3468dab
--- /dev/null
+++ b/src/openvpn/mudp.c
@@ -0,0 +1,291 @@
+/*
+ *  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
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#elif defined(_MSC_VER)
+#include "config-msvc.h"
+#endif
+
+#include "syshead.h"
+
+#if P2MP_SERVER
+
+#include "multi.h"
+#include "forward-inline.h"
+
+#include "memdbg.h"
+
+/*
+ * Get a client instance based on real address.  If
+ * the instance doesn't exist, create it while
+ * maintaining real address hash table atomicity.
+ */
+
+struct multi_instance *
+multi_get_create_instance_udp (struct multi_context *m)
+{
+  struct gc_arena gc = gc_new ();
+  struct mroute_addr real;
+  struct multi_instance *mi = NULL;
+  struct hash *hash = m->hash;
+
+  if (mroute_extract_openvpn_sockaddr (&real, &m->top.c2.from.dest, true))
+    {
+      struct hash_element *he;
+      const uint32_t hv = hash_value (hash, &real);
+      struct hash_bucket *bucket = hash_bucket (hash, hv);
+  
+      he = hash_lookup_fast (hash, bucket, &real, hv);
+
+      if (he)
+	{
+	  mi = (struct multi_instance *) he->value;
+	}
+      else
+	{
+	  if (!m->top.c2.tls_auth_standalone
+	      || tls_pre_decrypt_lite (m->top.c2.tls_auth_standalone, &m->top.c2.from, &m->top.c2.buf))
+	    {
+	      if (frequency_limit_event_allowed (m->new_connection_limiter))
+		{
+		  mi = multi_create_instance (m, &real);
+		  if (mi)
+		    {
+		      hash_add_fast (hash, bucket, &mi->real, hv, mi);
+		      mi->did_real_hash = true;
+		    }
+		}
+	      else
+		{
+		  msg (D_MULTI_ERRORS,
+		       "MULTI: Connection from %s would exceed new connection frequency limit as controlled by --connect-freq",
+		       mroute_addr_print (&real, &gc));
+		}
+	    }
+	}
+
+#ifdef ENABLE_DEBUG
+      if (check_debug_level (D_MULTI_DEBUG))
+	{
+	  const char *status;
+
+	  if (he && mi)
+	    status = "[succeeded]";
+	  else if (!he && mi)
+	    status = "[created]";
+	  else
+	    status = "[failed]";
+	
+	  dmsg (D_MULTI_DEBUG, "GET INST BY REAL: %s %s",
+	       mroute_addr_print (&real, &gc),
+	       status);
+	}
+#endif
+    }
+
+  gc_free (&gc);
+  ASSERT (!(mi && mi->halt));
+  return mi;
+}
+
+/*
+ * Send a packet to TCP/UDP socket.
+ */
+static inline void
+multi_process_outgoing_link (struct multi_context *m, const unsigned int mpp_flags)
+{
+  struct multi_instance *mi = multi_process_outgoing_link_pre (m);
+  if (mi)
+    multi_process_outgoing_link_dowork (m, mi, mpp_flags);
+}
+
+/*
+ * Process an I/O event.
+ */
+static void
+multi_process_io_udp (struct multi_context *m)
+{
+  const unsigned int status = m->top.c2.event_set_status;
+  const unsigned int mpp_flags = m->top.c2.fast_io
+    ? (MPP_CONDITIONAL_PRE_SELECT | MPP_CLOSE_ON_SIGNAL)
+    : (MPP_PRE_SELECT | MPP_CLOSE_ON_SIGNAL);
+
+#ifdef MULTI_DEBUG_EVENT_LOOP
+  char buf[16];
+  buf[0] = 0;
+  if (status & SOCKET_READ)
+    strcat (buf, "SR/");
+  else if (status & SOCKET_WRITE)
+    strcat (buf, "SW/");
+  else if (status & TUN_READ)
+    strcat (buf, "TR/");
+  else if (status & TUN_WRITE)
+    strcat (buf, "TW/");
+  printf ("IO %s\n", buf);
+#endif
+
+#ifdef ENABLE_MANAGEMENT
+  if (status & (MANAGEMENT_READ|MANAGEMENT_WRITE))
+    {
+      ASSERT (management);
+      management_io (management);
+    }
+#endif
+
+  /* UDP port ready to accept write */
+  if (status & SOCKET_WRITE)
+    {
+      multi_process_outgoing_link (m, mpp_flags);
+    }
+  /* TUN device ready to accept write */
+  else if (status & TUN_WRITE)
+    {
+      multi_process_outgoing_tun (m, mpp_flags);
+    }
+  /* Incoming data on UDP port */
+  else if (status & SOCKET_READ)
+    {
+      read_incoming_link (&m->top);
+      multi_release_io_lock (m);
+      if (!IS_SIG (&m->top))
+	multi_process_incoming_link (m, NULL, mpp_flags);
+    }
+  /* Incoming data on TUN device */
+  else if (status & TUN_READ)
+    {
+      read_incoming_tun (&m->top);
+      multi_release_io_lock (m);
+      if (!IS_SIG (&m->top))
+	multi_process_incoming_tun (m, mpp_flags);
+    }
+}
+
+/*
+ * Return the io_wait() flags appropriate for
+ * a point-to-multipoint tunnel.
+ */
+static inline unsigned int
+p2mp_iow_flags (const struct multi_context *m)
+{
+  unsigned int flags = IOW_WAIT_SIGNAL;
+  if (m->pending)
+    {
+      if (TUN_OUT (&m->pending->context))
+	flags |= IOW_TO_TUN;
+      if (LINK_OUT (&m->pending->context))
+	flags |= IOW_TO_LINK;
+    }
+  else if (mbuf_defined (m->mbuf))
+    flags |= IOW_MBUF;
+  else
+    flags |= IOW_READ;
+
+  return flags;
+}
+
+
+/**************************************************************************/
+/**
+ * Main event loop for OpenVPN in UDP server mode.
+ * @ingroup eventloop
+ *
+ * This function implements OpenVPN's main event loop for UDP server mode.
+ *  At this time, OpenVPN does not yet support multithreading.  This
+ * function's name is therefore slightly misleading.
+ *
+ * @param top - Top-level context structure.
+ */
+static void
+tunnel_server_udp_single_threaded (struct context *top)
+{
+  struct multi_context multi;
+
+  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, false, 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 udp */
+
+  /* per-packet event loop */
+  while (true)
+    {
+      perf_push (PERF_EVENT_LOOP);
+
+      /* set up and do the io_wait() */
+      multi_get_timeout (&multi, &multi.top.c2.timeval);
+      io_wait (&multi.top, p2mp_iow_flags (&multi));
+      MULTI_CHECK_SIG (&multi);
+
+      /* check on status of coarse timers */
+      multi_process_per_second_timers (&multi);
+
+      /* timeout? */
+      if (multi.top.c2.event_set_status == ES_TIMEOUT)
+	{
+	  multi_process_timeout (&multi, MPP_PRE_SELECT|MPP_CLOSE_ON_SIGNAL);
+	}
+      else
+	{
+	  /* process I/O */
+	  multi_process_io_udp (&multi);
+	  MULTI_CHECK_SIG (&multi);
+	}
+      
+      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);
+}
+
+void
+tunnel_server_udp (struct context *top)
+{
+  tunnel_server_udp_single_threaded (top);
+}
+
+#endif