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Diffstat (limited to 'openvpn.h')
| -rw-r--r-- | openvpn.h | 550 |
1 files changed, 550 insertions, 0 deletions
diff --git a/openvpn.h b/openvpn.h new file mode 100644 index 0000000..641bf93 --- /dev/null +++ b/openvpn.h @@ -0,0 +1,550 @@ +/* + * 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 + */ + +#ifndef OPENVPN_H +#define OPENVPN_H + +#include "buffer.h" +#include "options.h" +#include "socket.h" +#include "crypto.h" +#include "ssl.h" +#include "packet_id.h" +#include "lzo.h" +#include "tun.h" +#include "interval.h" +#include "status.h" +#include "fragment.h" +#include "shaper.h" +#include "route.h" +#include "proxy.h" +#include "socks.h" +#include "sig.h" +#include "misc.h" +#include "mbuf.h" +#include "pool.h" +#include "plugin.h" +#include "manage.h" +#include "pf.h" + +/* + * Our global key schedules, packaged thusly + * to facilitate --persist-key. + */ + +struct key_schedule +{ +#ifdef USE_CRYPTO + /* which cipher, HMAC digest, and key sizes are we using? */ + struct key_type key_type; + + /* pre-shared static key, read from a file */ + struct key_ctx_bi static_key; + +#ifdef USE_SSL + /* our global SSL context */ + SSL_CTX *ssl_ctx; + + /* optional authentication HMAC key for TLS control channel */ + struct key_ctx_bi tls_auth_key; + +#endif /* USE_SSL */ +#else /* USE_CRYPTO */ + int dummy; +#endif /* USE_CRYPTO */ +}; + +/* + * struct packet_id_persist should be empty if we are not + * building with crypto. + */ +#ifndef PACKET_ID_H +struct packet_id_persist +{ + int dummy; +}; +static inline void +packet_id_persist_init (struct packet_id_persist *p) +{ +} +#endif + +/* + * Packet processing buffers. + */ +struct context_buffers +{ + /* miscellaneous buffer, used by ping, occ, etc. */ + struct buffer aux_buf; + + /* workspace buffers used by crypto routines */ +#ifdef USE_CRYPTO + struct buffer encrypt_buf; + struct buffer decrypt_buf; +#endif + + /* workspace buffers for LZO compression */ +#ifdef USE_LZO + struct buffer lzo_compress_buf; + struct buffer lzo_decompress_buf; +#endif + + /* + * Buffers used to read from TUN device + * and TCP/UDP port. + */ + struct buffer read_link_buf; + struct buffer read_tun_buf; +}; + +/* + * always-persistent context variables + */ +struct context_persist +{ + int restart_sleep_seconds; +}; + +/* + * level 0 context contains data related to + * once-per OpenVPN instantiation events + * such as daemonization. + */ +struct context_0 +{ + /* workspace for get_pid_file/write_pid */ + struct pid_state pid_state; + + /* workspace for --user/--group */ + bool uid_gid_specified; + bool uid_gid_set; + struct user_state user_state; + struct group_state group_state; +}; + +/* + * Contains the persist-across-restart OpenVPN tunnel instance state. + * Reset only for SIGHUP restarts. + */ +struct context_1 +{ + /* local and remote addresses */ + struct link_socket_addr link_socket_addr; + + /* tunnel session keys */ + struct key_schedule ks; + + /* persist crypto sequence number to/from file */ + struct packet_id_persist pid_persist; + + /* TUN/TAP interface */ + struct tuntap *tuntap; + bool tuntap_owned; + + /* list of --route directives */ + struct route_list *route_list; + + /* --status file */ + struct status_output *status_output; + bool status_output_owned; + +#ifdef ENABLE_HTTP_PROXY + /* HTTP proxy object */ + struct http_proxy_info *http_proxy; + bool http_proxy_owned; +#endif + +#ifdef ENABLE_SOCKS + /* SOCKS proxy object */ + struct socks_proxy_info *socks_proxy; + bool socks_proxy_owned; +#endif + +#if P2MP + +#if P2MP_SERVER + /* persist --ifconfig-pool db to file */ + struct ifconfig_pool_persist *ifconfig_pool_persist; + bool ifconfig_pool_persist_owned; +#endif + + /* if client mode, hash of option strings we pulled from server */ + struct md5_digest pulled_options_digest_save; + + /* save user/pass for authentication */ + struct user_pass *auth_user_pass; +#endif +}; + +/* + * Contains the OpenVPN tunnel instance state, wiped across + * SIGUSR1 and SIGHUP restarts. + */ +struct context_2 +{ + /* garbage collection arena for context_2 scope */ + struct gc_arena gc; + + /* our global wait events */ + struct event_set *event_set; + int event_set_max; + bool event_set_owned; + + /* event flags returned by io_wait */ +# define SOCKET_READ (1<<0) +# define SOCKET_WRITE (1<<1) +# define TUN_READ (1<<2) +# define TUN_WRITE (1<<3) +# define ES_ERROR (1<<4) +# define ES_TIMEOUT (1<<5) +# ifdef ENABLE_MANAGEMENT +# define MANAGEMENT_READ (1<<6) +# define MANAGEMENT_WRITE (1<<7) +# endif + + unsigned int event_set_status; + + struct link_socket *link_socket; /* socket used for TCP/UDP connection to remote */ + bool link_socket_owned; + struct link_socket_info *link_socket_info; + const struct link_socket *accept_from; /* possibly do accept() on a parent link_socket */ + + struct link_socket_actual *to_link_addr; /* IP address of remote */ + struct link_socket_actual from; /* address of incoming datagram */ + + /* MTU frame parameters */ + struct frame frame; + +#ifdef ENABLE_FRAGMENT + /* Object to handle advanced MTU negotiation and datagram fragmentation */ + struct fragment_master *fragment; + struct frame frame_fragment; + struct frame frame_fragment_omit; +#endif + +#ifdef HAVE_GETTIMEOFDAY + /* + * Traffic shaper object. + */ + struct shaper shaper; +#endif + + /* + * Statistics + */ + counter_type tun_read_bytes; + counter_type tun_write_bytes; + counter_type link_read_bytes; + counter_type link_read_bytes_auth; + counter_type link_write_bytes; +#ifdef PACKET_TRUNCATION_CHECK + counter_type n_trunc_tun_read; + counter_type n_trunc_tun_write; + counter_type n_trunc_pre_encrypt; + counter_type n_trunc_post_decrypt; +#endif + + /* + * Timer objects for ping and inactivity + * timeout features. + */ + struct event_timeout wait_for_connect; + struct event_timeout ping_send_interval; + struct event_timeout ping_rec_interval; + + /* --inactive */ + struct event_timeout inactivity_interval; + int inactivity_bytes; + +#ifdef ENABLE_OCC + /* the option strings must match across peers */ + char *options_string_local; + char *options_string_remote; + + int occ_op; /* INIT to -1 */ + int occ_n_tries; + struct event_timeout occ_interval; +#endif + + /* + * Keep track of maximum packet size received so far + * (of authenticated packets). + */ + int original_recv_size; /* temporary */ + int max_recv_size_local; /* max packet size received */ + int max_recv_size_remote; /* max packet size received by remote */ + int max_send_size_local; /* max packet size sent */ + int max_send_size_remote; /* max packet size sent by remote */ + +#ifdef ENABLE_OCC + /* remote wants us to send back a load test packet of this size */ + int occ_mtu_load_size; + + struct event_timeout occ_mtu_load_test_interval; + int occ_mtu_load_n_tries; +#endif + +#ifdef USE_CRYPTO + + /* + * TLS-mode crypto objects. + */ +#ifdef USE_SSL + + /* master OpenVPN SSL/TLS object */ + struct tls_multi *tls_multi; + + /* check --tls-auth signature without needing + a full-size tls_multi object */ + struct tls_auth_standalone *tls_auth_standalone; + + /* used to optimize calls to tls_multi_process */ + struct interval tmp_int; + + /* throw this signal on TLS errors */ + int tls_exit_signal; + +#endif /* USE_SSL */ + + /* passed to encrypt or decrypt, contains all + crypto-related command line options related + to data channel encryption/decryption */ + struct crypto_options crypto_options; + + /* used to keep track of data channel packet sequence numbers */ + struct packet_id packet_id; + struct event_timeout packet_id_persist_interval; + +#endif /* USE_CRYPTO */ + + /* + * LZO compression library workspace. + */ +#ifdef USE_LZO + struct lzo_compress_workspace lzo_compwork; +#endif + + /* + * Buffers used for packet processing. + */ + struct context_buffers *buffers; + bool buffers_owned; /* if true, we should free all buffers on close */ + + /* + * These buffers don't actually allocate storage, they are used + * as pointers to the allocated buffers in + * struct context_buffers. + */ + struct buffer buf; + struct buffer to_tun; + struct buffer to_link; + + /* + * IPv4 TUN device? + */ + bool ipv4_tun; + + /* should we print R|W|r|w to console on packet transfers? */ + bool log_rw; + + /* route stuff */ + struct event_timeout route_wakeup; + struct event_timeout route_wakeup_expire; + + /* did we open tun/tap dev during this cycle? */ + bool did_open_tun; + + /* + * Event loop info + */ + + /* how long to wait on link/tun read before we will need to be serviced */ + struct timeval timeval; + + /* next wakeup for processing coarse timers (>1 sec resolution) */ + time_t coarse_timer_wakeup; + + /* maintain a random delta to add to timeouts to avoid contexts + waking up simultaneously */ + time_t update_timeout_random_component; + struct timeval timeout_random_component; + + /* indicates that the do_up_delay function has run */ + bool do_up_ran; + +#ifdef ENABLE_OCC + /* indicates that we have received a SIGTERM when + options->explicit_exit_notification is enabled, + but we have not exited yet */ + time_t explicit_exit_notification_time_wait; + struct event_timeout explicit_exit_notification_interval; +#endif + + /* environmental variables to pass to scripts */ + struct env_set *es; + bool es_owned; + + /* don't wait for TUN/TAP/UDP to be ready to accept write */ + bool fast_io; + +#if P2MP + +#if P2MP_SERVER + /* --ifconfig endpoints to be pushed to client */ + bool push_reply_deferred; + bool push_ifconfig_defined; + in_addr_t push_ifconfig_local; + in_addr_t push_ifconfig_remote_netmask; + + /* client authentication state, CAS_SUCCEEDED must be 0 */ +# define CAS_SUCCEEDED 0 +# define CAS_PENDING 1 +# define CAS_FAILED 2 +# define CAS_PARTIAL 3 /* at least one client-connect script/plugin + succeeded while a later one in the chain failed */ + int context_auth; +#endif + + struct event_timeout push_request_interval; + bool did_pre_pull_restore; + + /* hash of pulled options, so we can compare when options change */ + struct md5_state pulled_options_state; + struct md5_digest pulled_options_digest; + + struct event_timeout server_poll_interval; + + struct event_timeout scheduled_exit; + int scheduled_exit_signal; +#endif + + /* packet filter */ +#ifdef ENABLE_PF + struct pf_context pf; +#endif + +#ifdef MANAGEMENT_DEF_AUTH + struct man_def_auth_context mda_context; +#endif +}; + +/* + * Contains all state information for one tunnel. + */ +struct context +{ + /* command line or config file options */ + struct options options; + + /* true on initial VPN iteration */ + bool first_time; + + /* context modes */ +# define CM_P2P 0 /* standalone point-to-point session or client */ +# define CM_TOP 1 /* top level of a multi-client or point-to-multipoint server */ +# define CM_TOP_CLONE 2 /* clone of a CM_TOP context for one thread */ +# define CM_CHILD_UDP 3 /* child context of a CM_TOP or CM_THREAD */ +# define CM_CHILD_TCP 4 /* child context of a CM_TOP or CM_THREAD */ + int mode; + + /* garbage collection for context scope + allocations */ + struct gc_arena gc; + + /* environmental variable settings */ + struct env_set *es; + + /* signal info */ + struct signal_info *sig; + + /* shared object plugins */ + struct plugin_list *plugins; + bool plugins_owned; + + /* set to true after we daemonize */ + bool did_we_daemonize; + + /* persistent across SIGHUP */ + struct context_persist persist; + + /* level 0 context contains data related to + once-per OpenVPN instantiation events + such as daemonization */ + struct context_0 *c0; + + /* level 1 context is preserved for + SIGUSR1 restarts, but initialized + for SIGHUP restarts */ + struct context_1 c1; + + /* level 2 context is initialized for all + restarts (SIGUSR1 and SIGHUP) */ + struct context_2 c2; +}; + +/* + * Check for a signal when inside an event loop + */ +#define EVENT_LOOP_CHECK_SIGNAL(c, func, arg) \ + if (IS_SIG (c)) \ + { \ + const int brk = func (arg); \ + perf_pop (); \ + if (brk) \ + break; \ + else \ + continue; \ + } + +/* + * Macros for referencing objects which may not + * have been compiled in. + */ + +#if defined(USE_CRYPTO) && defined(USE_SSL) +#define TLS_MODE(c) ((c)->c2.tls_multi != NULL) +#define PROTO_DUMP_FLAGS (check_debug_level (D_LINK_RW_VERBOSE) ? (PD_SHOW_DATA|PD_VERBOSE) : 0) +#define PROTO_DUMP(buf, gc) protocol_dump((buf), \ + PROTO_DUMP_FLAGS | \ + (c->c2.tls_multi ? PD_TLS : 0) | \ + (c->options.tls_auth_file ? c->c1.ks.key_type.hmac_length : 0), \ + gc) +#else +#define TLS_MODE(c) (false) +#define PROTO_DUMP(buf, gc) format_hex (BPTR (buf), BLEN (buf), 80, gc) +#endif + +#ifdef USE_CRYPTO +#define MD5SUM(buf, len, gc) md5sum((buf), (len), 0, (gc)) +#else +#define MD5SUM(buf, len, gc) "[unavailable]" +#endif + +#ifdef USE_CRYPTO +#define CIPHER_ENABLED(c) (c->c1.ks.key_type.cipher != NULL) +#else +#define CIPHER_ENABLED(c) (false) +#endif + +#endif |