forward.c File Reference

#include "syshead.h"
#include "forward.h"
#include "init.h"
#include "push.h"
#include "gremlin.h"
#include "mss.h"
#include "event.h"
#include "occ.h"
#include "pf.h"
#include "ping.h"
#include "ps.h"
#include "dhcp.h"
#include "common.h"
#include "ssl_verify.h"
#include "memdbg.h"
#include "mstats.h"

Include dependency graph for forward.c:

Go to the source code of this file.

Macros
#define	MAX_ICMPV6LEN   1280

Functions
static void	check_tls_errors (struct context *c)
static void	context_immediate_reschedule (struct context *c)
static void	context_reschedule_sec (struct context *c, int sec)
void	check_tls (struct context *c)
void	check_tls_errors_co (struct context *c)
void	check_tls_errors_nco (struct context *c)
void	check_incoming_control_channel (struct context *c)
void	check_push_request (struct context *c)
void	check_connection_established (struct context *c)
bool	send_control_channel_string_dowork (struct tls_multi *multi, const char *str, int msglevel)
void	reschedule_multi_process (struct context *c)
	Reschedule tls_multi_process. More...
bool	send_control_channel_string (struct context *c, const char *str, int msglevel)
static void	check_add_routes_action (struct context *c, const bool errors)
void	check_add_routes (struct context *c)
void	check_inactivity_timeout (struct context *c)
int	get_server_poll_remaining_time (struct event_timeout *server_poll_timeout)
void	check_server_poll_timeout (struct context *c)
void	schedule_exit (struct context *c, const int n_seconds, const int signal)
void	check_scheduled_exit (struct context *c)
void	check_status_file (struct context *c)
void	check_fragment (struct context *c)
static void	buffer_turnover (const uint8_t *orig_buf, struct buffer *dest_stub, struct buffer *src_stub, struct buffer *storage)
void	encrypt_sign (struct context *c, bool comp_frag)
	Process a data channel packet that will be sent through a VPN tunnel. More...
static void	process_coarse_timers (struct context *c)
static void	check_coarse_timers (struct context *c)
static void	check_timeout_random_component_dowork (struct context *c)
static void	check_timeout_random_component (struct context *c)
static void	socks_postprocess_incoming_link (struct context *c)
static void	socks_preprocess_outgoing_link (struct context *c, struct link_socket_actual **to_addr, int *size_delta)
static void	link_socket_write_post_size_adjust (int *size, int size_delta, struct buffer *buf)
void	read_incoming_link (struct context *c)
	Read a packet from the external network interface. More...
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. More...
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. More...
static void	process_incoming_link (struct context *c)
void	read_incoming_tun (struct context *c)
	Read a packet from the virtual tun/tap network interface. More...
static void	drop_if_recursive_routing (struct context *c, struct buffer *buf)
	Drops UDP packets which OS decided to route via tun. More...
void	process_incoming_tun (struct context *c)
	Process a packet read from the virtual tun/tap network interface. More...
void	ipv6_send_icmp_unreachable (struct context *c, struct buffer *buf, bool client)
	Forges a IPv6 ICMP packet with a no route to host error code from the IPv6 packet in buf and sends it directly back to the client via the tun device when used on a client and via the link if used on the server. More...
void	process_ip_header (struct context *c, unsigned int flags, struct buffer *buf)
void	process_outgoing_link (struct context *c)
	Write a packet to the external network interface. More...
void	process_outgoing_tun (struct context *c)
	Write a packet to the virtual tun/tap network interface. More...
void	pre_select (struct context *c)
void	io_wait_dowork (struct context *c, const unsigned int flags)
void	process_io (struct context *c)

Variables
counter_type	link_read_bytes_global
counter_type	link_write_bytes_global

Macro Definition Documentation

MAX_ICMPV6LEN

#define MAX_ICMPV6LEN   1280

Referenced by ipv6_send_icmp_unreachable().

Function Documentation

buffer_turnover()

static void buffer_turnover ( const uint8_t *  orig_buf, struct buffer *  dest_stub, struct buffer *  src_stub, struct buffer *  storage  )

inlinestatic

Definition at line 509 of file forward.c.

References buf_assign(), and buffer::data.

Referenced by encrypt_sign(), and process_incoming_link_part2().

check_add_routes()

void check_add_routes

(

struct context *

c

)

Definition at line 374 of file forward.c.

References context::c1, context::c2, check_add_routes_action(), D_ROUTE, ETT_DEFAULT, event_timeout_init(), event_timeout_reset(), event_timeout_trigger(), M_INFO, M_NOPREFIX, msg, event_timeout::n, now, context::persist, context_2::ping_rec_interval, register_signal(), context_persist::restart_sleep_seconds, context_1::route_list, context_2::route_wakeup, context_2::route_wakeup_expire, show_adapters(), show_routes(), SIGHUP, test_routes(), context_2::timeval, tun_standby(), context_1::tuntap, and update_time().

Referenced by process_coarse_timers().

check_add_routes_action()

static void check_add_routes_action ( struct context *  c, const bool  errors  )

static

Definition at line 363 of file forward.c.

References context::c1, context::c2, do_route(), context_2::es, event_timeout_clear(), initialization_sequence_completed(), ISC_ERRORS, context::net_ctx, context::options, context::plugins, context_1::route_ipv6_list, context_1::route_list, context_2::route_wakeup, context_2::route_wakeup_expire, context_1::tuntap, and update_time().

Referenced by check_add_routes().

check_coarse_timers()

static void check_coarse_timers ( struct context *  c )

static

Definition at line 708 of file forward.c.

References BIG_TIMEOUT, context::c2, context_2::coarse_timer_wakeup, context_reschedule_sec(), D_INTERVAL, dmsg, now, process_coarse_timers(), and context_2::timeval.

Referenced by pre_select().

check_connection_established()

void check_connection_established

(

struct context *

c

)

Definition at line 280 of file forward.c.

References context::c2, CONNECTION_ESTABLISHED, do_up(), event_timeout_clear(), event_timeout_init(), options::handshake_window, management_set_state(), now, OPENVPN_STATE_GET_CONFIG, context::options, options::pull, context_2::push_request_interval, context_2::push_request_timeout, reset_coarse_timers(), context_2::tls_multi, and context_2::wait_for_connect.

Referenced by process_coarse_timers().

check_fragment()

void check_fragment

(

struct context *

c

)

Definition at line 479 of file forward.c.

References ASSERT, context_2::buf, context::c2, options::ce, encrypt_sign(), context_2::fragment, fragment_housekeeping(), fragment_outgoing_defined(), fragment_ready_to_send(), frame_adjust_path_mtu(), context_2::frame_fragment, get_link_socket_info(), buffer::len, context_2::link_socket, link_socket::mtu, link_socket_info::mtu_changed, context::options, connection_entry::proto, context_2::timeval, and context_2::to_link.

Referenced by pre_select().

check_inactivity_timeout()

void check_inactivity_timeout

(

struct context *

c

)

Definition at line 412 of file forward.c.

References M_INFO, msg, register_signal(), and SIGTERM.

Referenced by process_coarse_timers().

check_incoming_control_channel()

void check_incoming_control_channel

(

struct context *

c

)

Definition at line 197 of file forward.c.

References alloc_buf_gc(), ASSERT, BSTR, buf_null_terminate(), buf_string_match_head_str(), context::c2, CC_CRLF, CC_PRINT, D_PUSH_ERRORS, gc_free(), gc_new(), incoming_push_message(), msg, receive_auth_failed(), receive_auth_pending(), receive_cr_response(), server_pushed_info(), server_pushed_signal(), string_mod(), context_2::tls_multi, tls_rec_payload(), and tls_test_payload_len().

Referenced by pre_select().

check_push_request()

void check_push_request

(

struct context *

c

)

Definition at line 262 of file forward.c.

References context::c2, event_timeout_modify_wakeup(), PUSH_REQUEST_INTERVAL, context_2::push_request_interval, and send_push_request().

Referenced by process_coarse_timers().

check_scheduled_exit()

void check_scheduled_exit

(

struct context *

c

)

Definition at line 457 of file forward.c.

References context::c2, register_signal(), and context_2::scheduled_exit_signal.

Referenced by process_coarse_timers().

check_server_poll_timeout()

void check_server_poll_timeout

(

struct context *

c

)

Definition at line 427 of file forward.c.

References ASSERT, context::c2, event_timeout_reset(), M_INFO, msg, context::persist, register_signal(), context_persist::restart_sleep_seconds, context_2::server_poll_interval, SIGUSR1, tls_initial_packet_received(), and context_2::tls_multi.

Referenced by process_coarse_timers().

check_status_file()

void check_status_file

(

struct context *

c

)

Definition at line 466 of file forward.c.

References context::c1, print_status(), and context_1::status_output.

Referenced by process_coarse_timers().

check_timeout_random_component()

static void check_timeout_random_component ( struct context *  c )

inlinestatic

Definition at line 743 of file forward.c.

References context::c2, check_timeout_random_component_dowork(), now, context_2::timeout_random_component, context_2::timeval, tv_add(), and context_2::update_timeout_random_component.

Referenced by pre_select().

check_timeout_random_component_dowork()

static void check_timeout_random_component_dowork ( struct context *  c )

static

Definition at line 732 of file forward.c.

References context::c2, D_INTERVAL, dmsg, get_random(), now, context_2::timeout_random_component, and context_2::update_timeout_random_component.

Referenced by check_timeout_random_component().

check_tls()

void check_tls

(

struct context *

c

)

Definition at line 142 of file forward.c.

References BIG_TIMEOUT, context::c2, tls_multi::client_reason, context_reschedule_sec(), get_link_socket_info(), interval_action(), interval_future_trigger(), interval_schedule_wakeup(), interval_test(), options::mode, MODE_SERVER, context::options, register_signal(), send_auth_failed(), SIGTERM, context_2::tls_multi, tls_multi_process(), TLSMP_ACTIVE, TLSMP_KILL, context_2::tmp_int, context_2::to_link, context_2::to_link_addr, and update_time().

Referenced by pre_select().

check_tls_errors()

static void check_tls_errors ( struct context *  c )

inlinestatic

Definition at line 85 of file forward.c.

References context::c2, check_tls_errors_co(), check_tls_errors_nco(), context_2::link_socket, link_socket_connection_oriented(), tls_multi::n_hard_errors, tls_multi::n_soft_errors, context_2::tls_exit_signal, and context_2::tls_multi.

Referenced by pre_select().

check_tls_errors_co()

void check_tls_errors_co

(

struct context *

c

)

Definition at line 180 of file forward.c.

References context::c2, D_STREAM_ERRORS, msg, register_signal(), and context_2::tls_exit_signal.

Referenced by check_tls_errors().

check_tls_errors_nco()

void check_tls_errors_nco

(

struct context *

c

)

Definition at line 187 of file forward.c.

References context::c2, register_signal(), and context_2::tls_exit_signal.

Referenced by check_tls_errors().

context_immediate_reschedule()

static void context_immediate_reschedule ( struct context *  c )

inlinestatic

Definition at line 111 of file forward.c.

References context::c2, and context_2::timeval.

Referenced by reschedule_multi_process().

context_reschedule_sec()

static void context_reschedule_sec ( struct context *  c, int  sec  )

inlinestatic

Definition at line 118 of file forward.c.

References context::c2, and context_2::timeval.

Referenced by check_coarse_timers(), and check_tls().

drop_if_recursive_routing()

static void drop_if_recursive_routing ( struct context *  c, struct buffer *  buf  )

static

Drops UDP packets which OS decided to route via tun.

On Windows and OS X when netwotk adapter is disabled or disconnected, platform starts to use tun as external interface. When packet is sent to tun, it comes to openvpn, encapsulated and sent to routing table, which sends it again to tun.

Definition at line 1177 of file forward.c.

References openvpn_sockaddr::addr, BLEN, BPTR, context_2::buf, context::c1, context::c2, D_LOW, openvpn_iphdr::daddr, openvpn_ipv6hdr::daddr, link_socket_actual::dest, gc_free(), gc_new(), get_tun_ip_ver(), openvpn_sockaddr::in4, openvpn_sockaddr::in6, IN6_ARE_ADDR_EQUAL, buffer::len, msg, print_link_socket_actual(), openvpn_sockaddr::sa, context_2::to_link_addr, TUNNEL_TYPE, and context_1::tuntap.

Referenced by process_incoming_tun().

get_server_poll_remaining_time()

int get_server_poll_remaining_time

(

struct event_timeout *

server_poll_timeout

)

Definition at line 419 of file forward.c.

References event_timeout_remaining(), max_int(), and update_time().

Referenced by establish_http_proxy_passthru(), phase2_socks_client(), and phase2_tcp_client().

io_wait_dowork()

void io_wait_dowork	(	struct context *	c,
		const unsigned int	flags
	)

Definition at line 1864 of file forward.c.

References event_set_return::arg, context::c1, context::c2, check_debug_level(), check_status(), D_EVENT_WAIT, dmsg, ERR_SHIFT, ES_ERROR, ES_TIMEOUT, event_ctl(), EVENT_READ, event_reset(), context_2::event_set, context_2::event_set_status, event_wait(), EVENT_WRITE, FILE_SHIFT, get_signal(), IOW_CHECK_RESIDUAL, IOW_FRAG, IOW_MBUF, IOW_READ_LINK, IOW_READ_TUN, IOW_READ_TUN_FORCE, IOW_SHAPER, IOW_TO_LINK, IOW_TO_TUN, IOW_WAIT_SIGNAL, context_2::link_socket, MANAGEMENT_SHIFT, management_socket_set(), max_int(), options::mode, MODE_SERVER, context::options, event_set_return::rwflags, context_2::shaper, options::shaper, shaper_delay(), shaper_soonest_event(), show_wait_status(), context::sig, signal_info::signal_received, SIZE, SOCKET_READ, socket_read_residual(), socket_set(), SOCKET_SHIFT, status, context_2::timeval, TO_LINK_FRAG, tun_set(), TUN_SHIFT, context_1::tuntap, tuntap_is_wintun(), update_time(), and wait_signal().

Referenced by io_wait().

ipv6_send_icmp_unreachable()

void ipv6_send_icmp_unreachable	(	struct context *	c,
		struct buffer *	buf,
		bool	client
	)

Forges a IPv6 ICMP packet with a no route to host error code from the IPv6 packet in buf and sends it directly back to the client via the tun device when used on a client and via the link if used on the server.

Parameters

buf	- The buf containing the packet for which the icmp6 unreachable should be constructed.
client	- determines whether to the send packet back via tun or link

Definition at line 1326 of file forward.c.

References ASSERT, context_buffers::aux_buf, BLEN, BPTR, buf_copy_n(), buf_init, buf_safe(), buf_write_prepend(), context_2::buffers, context::c1, context::c2, CLEAR, openvpn_ipv6hdr::daddr, openvpn_ethhdr::dest, DEV_TYPE_TAP, context_2::frame, openvpn_icmp6hdr::icmp6_cksum, openvpn_icmp6hdr::icmp6_code, openvpn_icmp6hdr::icmp6_type, options::ifconfig_ipv6_remote, ip_checksum(), is_ipv6(), MAX_ICMPV6LEN, min_int(), openvpn_ipv6hdr::nexthdr, OPENVPN_ETH_ALEN, OPENVPN_ETH_P_IPV6, OPENVPN_ICMP6_DESTINATION_UNREACHABLE, OPENVPN_ICMP6_DU_NOROUTE, OPENVPN_IPPROTO_ICMPV6, context::options, openvpn_ipv6hdr::payload_len, openvpn_ethhdr::proto, openvpn_ipv6hdr::saddr, openvpn_ethhdr::source, context_2::to_link, context_2::to_tun, TUN_MTU_SIZE, TUNNEL_TYPE, context_1::tuntap, and openvpn_ipv6hdr::version_prio.

Referenced by process_ip_header().

link_socket_write_post_size_adjust()

static void link_socket_write_post_size_adjust ( int *  size, int  size_delta, struct buffer *  buf  )

inlinestatic

Definition at line 783 of file forward.c.

References buf_advance().

Referenced by process_outgoing_link().

pre_select()

void pre_select

(

struct context *

c

)

Definition at line 1792 of file forward.c.

References BIG_TIMEOUT, context::c1, context::c2, check_coarse_timers(), check_debug_level(), check_fragment(), check_incoming_control_channel(), check_send_occ_msg(), check_timeout_random_component(), check_tls(), check_tls_errors(), D_TAP_WIN_DEBUG, context_2::fragment, context::sig, signal_info::signal_received, context_2::timeval, context_2::tls_multi, tls_test_payload_len(), tun_show_debug(), context_1::tuntap, and tuntap_defined().

Referenced by multi_process_post(), and tunnel_point_to_point().

process_coarse_timers()

static void process_coarse_timers ( struct context *  c )

static

Definition at line 608 of file forward.c.

References context::c1, context::c2, options::ce, check_add_routes(), check_connection_established(), check_inactivity_timeout(), check_ping_restart(), check_ping_send(), check_push_request(), check_scheduled_exit(), check_send_occ_load_test(), check_send_occ_req(), check_server_poll_timeout(), check_status_file(), connection_entry::connect_timeout, status_output::et, ETT_DEFAULT, event_timeout_trigger(), context_2::explicit_exit_notification_time_wait, context_2::inactivity_interval, options::inactivity_timeout, context::options, packet_id_persist_enabled(), context_2::packet_id_persist_interval, packet_id_persist_save(), context_1::pid_persist, process_explicit_exit_notification_timer_wakeup(), context_2::push_request_interval, context_2::route_wakeup, context_2::scheduled_exit, context_2::server_poll_interval, context::sig, signal_info::signal_received, context_1::status_output, context_2::timeval, context_2::tls_multi, and context_2::wait_for_connect.

Referenced by check_coarse_timers().

process_incoming_link()

static void process_incoming_link ( struct context *  c )

static

Definition at line 1083 of file forward.c.

References context_2::buf, context::c2, buffer::data, get_link_socket_info(), perf_pop(), PERF_PROC_IN_LINK, perf_push(), process_incoming_link_part1(), and process_incoming_link_part2().

Referenced by process_io().

process_io()

void process_io

(

struct context *

c

)

Definition at line 2071 of file forward.c.

References ASSERT, context::c2, context_2::event_set_status, IS_SIG, management_io(), MANAGEMENT_READ, MANAGEMENT_WRITE, process_incoming_link(), process_incoming_tun(), process_outgoing_link(), process_outgoing_tun(), read_incoming_link(), read_incoming_tun(), SOCKET_READ, SOCKET_WRITE, status, TUN_READ, and TUN_WRITE.

Referenced by tunnel_point_to_point().

process_ip_header()

void process_ip_header	(	struct context *	c,
		unsigned int	flags,
		struct buffer *	buf
	)

Definition at line 1452 of file forward.c.

References options::block_ipv6, context::c1, context::c2, options::ce, options::client_nat, client_nat_transform(), CN_INCOMING, CN_OUTGOING, dhcp_extract_router_msg(), context_2::es, context_2::frame, in_addr_t, ipv6_send_icmp_unreachable(), is_ipv4(), is_ipv6(), buffer::len, context_2::link_socket, mss_fixup_ipv4(), mss_fixup_ipv6(), connection_entry::mssfix, MTU_TO_MSS, context::options, PASSTOS_CAPABILITY, PIP_MSSFIX, PIP_OUTGOING, PIPV4_CLIENT_NAT, PIPV4_EXTRACT_DHCP_ROUTER, PIPV4_PASSTOS, PIPV6_IMCP_NOHOST_CLIENT, PIPV6_IMCP_NOHOST_SERVER, options::route_gateway_via_dhcp, context_1::route_list, route_list_add_vpn_gateway(), TUN_MTU_SIZE_DYNAMIC, TUNNEL_TYPE, and context_1::tuntap.

Referenced by multi_get_queue(), process_incoming_tun(), and process_outgoing_tun().

reschedule_multi_process()

void reschedule_multi_process

(

struct context *

c

)

Reschedule tls_multi_process.

NOTE: in multi-client mode, usually calling the function is insufficient to reschedule the client instance object unless multi_schedule_context_wakeup(m, mi) is also called.

Definition at line 339 of file forward.c.

References context::c2, context_immediate_reschedule(), interval_action(), and context_2::tmp_int.

Referenced by management_client_pending_auth(), and send_control_channel_string().

schedule_exit()

void schedule_exit	(	struct context *	c,
		const int	n_seconds,
		const int	signal
	)

Definition at line 443 of file forward.c.

References context::c2, D_SCHED_EXIT, event_timeout_init(), msg, now, reset_coarse_timers(), context_2::scheduled_exit, context_2::scheduled_exit_signal, context_2::tls_multi, tls_set_single_session(), and update_time().

Referenced by send_auth_failed(), and send_restart().

send_control_channel_string()

bool send_control_channel_string	(	struct context *	c,
		const char *	str,
		int	msglevel
	)

Definition at line 346 of file forward.c.

References context::c2, reschedule_multi_process(), send_control_channel_string_dowork(), and context_2::tls_multi.

Referenced by management_callback_send_cc_message(), multi_push_restart_schedule_exit(), send_auth_failed(), send_push_options(), send_push_reply(), send_push_request(), and send_restart().

send_control_channel_string_dowork()

bool send_control_channel_string_dowork	(	struct tls_multi *	multi,
		const char *	str,
		int	msglevel
	)

Definition at line 321 of file forward.c.

References gc_free(), gc_new(), msg, sanitize_control_message(), tls_common_name(), and tls_send_payload().

Referenced by send_auth_pending_messages(), send_control_channel_string(), and send_push_reply_auth_token().

socks_postprocess_incoming_link()

static void socks_postprocess_incoming_link ( struct context *  c )

inlinestatic

Definition at line 761 of file forward.c.

References context_2::buf, context::c2, context_2::from, link_socket::info, context_2::link_socket, link_socket_info::proto, PROTO_UDP, socks_process_incoming_udp(), and link_socket::socks_proxy.

Referenced by read_incoming_link().

socks_preprocess_outgoing_link()

static void socks_preprocess_outgoing_link ( struct context *  c, struct link_socket_actual **  to_addr, int *  size_delta  )

inlinestatic

Definition at line 770 of file forward.c.

References context::c2, link_socket::info, context_2::link_socket, link_socket_info::proto, PROTO_UDP, socks_process_outgoing_udp(), link_socket::socks_proxy, link_socket::socks_relay, context_2::to_link, and context_2::to_link_addr.

Referenced by process_outgoing_link().

Variable Documentation

link_read_bytes_global

counter_type link_read_bytes_global

Definition at line 50 of file forward.c.

Referenced by man_load_stats(), and process_incoming_link_part1().

link_write_bytes_global

counter_type link_write_bytes_global

Definition at line 51 of file forward.c.

Referenced by man_load_stats(), and process_outgoing_link().