OpenVPN
forward.h
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1 /*
2  * OpenVPN -- An application to securely tunnel IP networks
3  * over a single TCP/UDP port, with support for SSL/TLS-based
4  * session authentication and key exchange,
5  * packet encryption, packet authentication, and
6  * packet compression.
7  *
8  * Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2
12  * as published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write to the Free Software Foundation, Inc.,
21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
22  */
23 
24 
31 #ifndef FORWARD_H
32 #define FORWARD_H
33 
34 /* the following macros must be defined before including any other header
35  * file
36  */
37 
38 #define TUN_OUT(c) (BLEN(&(c)->c2.to_tun) > 0)
39 #define LINK_OUT(c) (BLEN(&(c)->c2.to_link) > 0)
40 #define ANY_OUT(c) (TUN_OUT(c) || LINK_OUT(c))
41 
42 #ifdef ENABLE_FRAGMENT
43 #define TO_LINK_FRAG(c) ((c)->c2.fragment && fragment_outgoing_defined((c)->c2.fragment))
44 #else
45 #define TO_LINK_FRAG(c) (false)
46 #endif
47 
48 #define TO_LINK_DEF(c) (LINK_OUT(c) || TO_LINK_FRAG(c))
49 
50 #include "openvpn.h"
51 #include "occ.h"
52 #include "ping.h"
53 
54 #define IOW_TO_TUN (1<<0)
55 #define IOW_TO_LINK (1<<1)
56 #define IOW_READ_TUN (1<<2)
57 #define IOW_READ_LINK (1<<3)
58 #define IOW_SHAPER (1<<4)
59 #define IOW_CHECK_RESIDUAL (1<<5)
60 #define IOW_FRAG (1<<6)
61 #define IOW_MBUF (1<<7)
62 #define IOW_READ_TUN_FORCE (1<<8)
63 #define IOW_WAIT_SIGNAL (1<<9)
64 
65 #define IOW_READ (IOW_READ_TUN|IOW_READ_LINK)
66 
68 
70 
71 void check_tls_dowork(struct context *c);
72 
73 void check_tls_errors_co(struct context *c);
74 
75 void check_tls_errors_nco(struct context *c);
76 
77 #if P2MP
79 
80 void check_scheduled_exit_dowork(struct context *c);
81 
82 void check_push_request_dowork(struct context *c);
83 #endif /* P2MP */
84 
85 #ifdef ENABLE_FRAGMENT
86 void check_fragment_dowork(struct context *c);
87 #endif /* ENABLE_FRAGMENT */
88 
90 
91 void check_add_routes_dowork(struct context *c);
92 
94 
96 
97 void check_status_file_dowork(struct context *c);
98 
99 void io_wait_dowork(struct context *c, const unsigned int flags);
100 
101 void pre_select(struct context *c);
102 
103 void process_io(struct context *c);
104 
105 const char *wait_status_string(struct context *c, struct gc_arena *gc);
106 
107 void show_wait_status(struct context *c);
108 
109 
110 /**********************************************************************/
143 void encrypt_sign(struct context *c, bool comp_frag);
144 
145 int get_server_poll_remaining_time(struct event_timeout *server_poll_timeout);
146 
147 /**********************************************************************/
167 void read_incoming_link(struct context *c);
168 
195 bool process_incoming_link_part1(struct context *c, struct link_socket_info *lsi, bool floated);
196 
222 void process_incoming_link_part2(struct context *c, struct link_socket_info *lsi, const uint8_t *orig_buf);
223 
236 void process_outgoing_link(struct context *c);
237 
238 
239 /**************************************************************************/
252 void read_incoming_tun(struct context *c);
253 
254 
267 void process_incoming_tun(struct context *c);
268 
269 
282 void process_outgoing_tun(struct context *c);
283 
284 
285 /**************************************************************************/
286 
287 bool send_control_channel_string(struct context *c, const char *str, int msglevel);
288 
289 #define PIPV4_PASSTOS (1<<0)
290 #define PIP_MSSFIX (1<<1) /* v4 and v6 */
291 #define PIPV4_OUTGOING (1<<2)
292 #define PIPV4_EXTRACT_DHCP_ROUTER (1<<3)
293 #define PIPV4_CLIENT_NAT (1<<4)
294 
295 void process_ip_header(struct context *c, unsigned int flags, struct buffer *buf);
296 
297 #if P2MP
298 void schedule_exit(struct context *c, const int n_seconds, const int signal);
299 
300 #endif
301 
302 static inline struct link_socket_info *
304 {
305  if (c->c2.link_socket_info)
306  {
307  return c->c2.link_socket_info;
308  }
309  else
310  {
311  return &c->c2.link_socket->info;
312  }
313 }
314 
315 static inline void
316 register_activity(struct context *c, const int size)
317 {
319  {
320  c->c2.inactivity_bytes += size;
322  {
323  c->c2.inactivity_bytes = 0;
325  }
326  }
327 }
328 
329 /*
330  * Return the io_wait() flags appropriate for
331  * a point-to-point tunnel.
332  */
333 static inline unsigned int
334 p2p_iow_flags(const struct context *c)
335 {
337  if (c->c2.to_link.len > 0)
338  {
339  flags |= IOW_TO_LINK;
340  }
341  if (c->c2.to_tun.len > 0)
342  {
343  flags |= IOW_TO_TUN;
344  }
345  return flags;
346 }
347 
348 /*
349  * This is the core I/O wait function, used for all I/O waits except
350  * for TCP in server mode.
351  */
352 static inline void
353 io_wait(struct context *c, const unsigned int flags)
354 {
355  void io_wait_dowork(struct context *c, const unsigned int flags);
356 
357  if (c->c2.fast_io && (flags & (IOW_TO_TUN|IOW_TO_LINK|IOW_MBUF)))
358  {
359  /* fast path -- only for TUN/TAP/UDP writes */
360  unsigned int ret = 0;
361  if (flags & IOW_TO_TUN)
362  {
363  ret |= TUN_WRITE;
364  }
365  if (flags & (IOW_TO_LINK|IOW_MBUF))
366  {
367  ret |= SOCKET_WRITE;
368  }
369  c->c2.event_set_status = ret;
370  }
371  else
372  {
373  /* slow path */
374  io_wait_dowork(c, flags);
375  }
376 }
377 
378 #define CONNECTION_ESTABLISHED(c) (get_link_socket_info(c)->connection_established)
379 
380 #endif /* FORWARD_H */
void check_tls_dowork(struct context *c)
Definition: forward.c:317
bool send_control_channel_string(struct context *c, const char *str, int msglevel)
Definition: forward.c:473
static void register_activity(struct context *c, const int size)
Definition: forward.h:316
struct buffer to_link
Definition: openvpn.h:382
void check_add_routes_dowork(struct context *c)
Definition: forward.c:519
struct options options
Options loaded from command line or configuration file.
Definition: openvpn.h:500
Contains all state information for one tunnel.
Definition: openvpn.h:498
int inactivity_minimum_bytes
Definition: options.h:257
struct link_socket_info * link_socket_info
Definition: openvpn.h:252
#define IOW_SHAPER
Definition: forward.h:58
#define IOW_TO_LINK
Definition: forward.h:55
void read_incoming_link(struct context *c)
Read a packet from the external network interface.
Definition: forward.c:933
void encrypt_sign(struct context *c, bool comp_frag)
Process a data channel packet that will be sent through a VPN tunnel.
Definition: forward.c:676
list flags
int len
Length in bytes of the actual content within the allocated memory.
Definition: buffer.h:66
void process_io(struct context *c)
Definition: forward.c:2026
#define IOW_TO_TUN
Definition: forward.h:54
struct event_timeout inactivity_interval
Definition: openvpn.h:300
void pre_select(struct context *c)
Definition: forward.c:1764
void process_ip_header(struct context *c, unsigned int flags, struct buffer *buf)
Definition: forward.c:1437
static struct link_socket_info * get_link_socket_info(struct context *c)
Definition: forward.h:303
static void event_timeout_reset(struct event_timeout *et)
Definition: interval.h:174
void io_wait_dowork(struct context *c, const unsigned int flags)
Definition: forward.c:1828
void show_wait_status(struct context *c)
int inactivity_bytes
Definition: openvpn.h:301
#define IOW_MBUF
Definition: forward.h:61
void check_inactivity_timeout_dowork(struct context *c)
Definition: forward.c:557
void check_incoming_control_channel_dowork(struct context *c)
Definition: forward.c:367
#define IOW_FRAG
Definition: forward.h:60
void check_fragment_dowork(struct context *c)
Definition: forward.c:627
static void io_wait(struct context *c, const unsigned int flags)
Definition: forward.h:353
void process_outgoing_link(struct context *c)
Write a packet to the external network interface.
Definition: forward.c:1522
unsigned int counter_type
Definition: common.h:38
struct link_socket * link_socket
Definition: openvpn.h:250
void check_push_request_dowork(struct context *c)
Definition: forward.c:416
struct context_2 c2
Level 2 context.
Definition: openvpn.h:537
void read_incoming_tun(struct context *c)
Read a packet from the virtual tun/tap network interface.
Definition: forward.c:1243
#define IOW_WAIT_SIGNAL
Definition: forward.h:63
int inactivity_timeout
Definition: options.h:256
unsigned __int8 uint8_t
Definition: config-msvc.h:123
counter_type link_read_bytes_global
Definition: forward.c:50
void check_tls_errors_co(struct context *c)
Definition: forward.c:348
Wrapper structure for dynamically allocated memory.
Definition: buffer.h:60
#define IOW_CHECK_RESIDUAL
Definition: forward.h:59
void check_server_poll_timeout_dowork(struct context *c)
Definition: forward.c:573
void check_connection_established_dowork(struct context *c)
Definition: forward.c:430
#define TUN_WRITE
Definition: openvpn.h:237
bool fast_io
Definition: openvpn.h:429
#define SOCKET_WRITE
Definition: openvpn.h:235
Garbage collection arena used to keep track of dynamically allocated memory.
Definition: buffer.h:116
void check_status_file_dowork(struct context *c)
Definition: forward.c:614
void check_scheduled_exit_dowork(struct context *c)
Definition: forward.c:603
void process_incoming_link_part2(struct context *c, struct link_socket_info *lsi, const uint8_t *orig_buf)
Continues processing a packet read from the external network interface.
Definition: forward.c:1140
void check_tls_errors_nco(struct context *c)
Definition: forward.c:355
int get_server_poll_remaining_time(struct event_timeout *server_poll_timeout)
Definition: forward.c:564
static unsigned int p2p_iow_flags(const struct context *c)
Definition: forward.h:334
bool process_incoming_link_part1(struct context *c, struct link_socket_info *lsi, bool floated)
Starts processing a packet read from the external network interface.
Definition: forward.c:1001
struct buffer to_tun
Definition: openvpn.h:381
unsigned int event_set_status
Definition: openvpn.h:248
void process_incoming_tun(struct context *c)
Process a packet read from the virtual tun/tap network interface.
Definition: forward.c:1384
const char * wait_status_string(struct context *c, struct gc_arena *gc)
void process_outgoing_tun(struct context *c)
Write a packet to the virtual tun/tap network interface.
Definition: forward.c:1673
#define IOW_READ
Definition: forward.h:65
void schedule_exit(struct context *c, const int n_seconds, const int signal)
Definition: forward.c:589
counter_type link_write_bytes_global
Definition: forward.c:51