/* information about connections between hosts and clients * Copyright (C) 1998-2001 D. Hugh Redelmeier * Copyright (C) 2009-2010 Andreas Steffen - Hochschule fuer Technik Rapperswil * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. See . * * 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. */ #ifndef _CONNECTIONS_H #define _CONNECTIONS_H #include #include #include #include #include #include "certs.h" #include "smartcard.h" #include "whack.h" /* There are two kinds of connections: * - ISAKMP connections, between hosts (for IKE communication) * - IPsec connections, between clients (for secure IP communication) * * An ISAKMP connection looks like: * host<--->host * * An IPsec connection looks like: * client-subnet<-->host<->nexthop<--->nexthop<->host<-->client-subnet * * For the connection to be relevant to this instance of Pluto, * exactly one of the hosts must be a public interface of our machine * known to this instance. * * The client subnet might simply be the host -- this is a * representation of "host mode". * * Each nexthop defaults to the neighbouring host's IP address. * The nexthop is a property of the pair of hosts, not each * individually. It is only needed for IPsec because of the * way IPsec is mixed into the kernel routing logic. Furthermore, * only this end's nexthop is actually used. Eventually, nexthop * will be unnecessary. * * Other information represented: * - each connection has a name: a chunk of uninterpreted text * that is unique for each connection. * - security requirements (currently just the "policy" flags from * the whack command to initiate the connection, but eventually * much more. Different for ISAKMP and IPsec connections. * - rekeying parameters: * + time an SA may live * + time before SA death that a rekeying should be attempted * (only by the initiator) * + number of times to attempt rekeying * - With the current KLIPS, we must route packets for a client * subnet through the ipsec interface (ipsec0). Only one * gateway can get traffic for a specific (client) subnet. * Furthermore, if the routing isn't in place, packets will * be sent in the clear. * "routing" indicates whether the routing has been done for * this connection. Note that several connections may claim * the same routing, as long as they agree about where the * packets are to be sent. * - With the current KLIPS, only one outbound IPsec SA bundle can be * used for a particular client. This is due to a limitation * of using only routing for selection. So only one IPsec state (SA) * may "own" the eroute. "eroute_owner" is the serial number of * this state, SOS_NOBODY if there is none. "routing" indicates * what kind of erouting has been done for this connection, if any. * * Details on routing is in constants.h * * Operations on Connections: * * - add a new connection (with all details) [whack command] * - delete a connection (by name) [whack command] * - initiate a connection (by name) [whack command] * - find a connection (by IP addresses of hosts) * [response to peer request; finding ISAKMP connection for IPsec connection] * * Some connections are templates, missing the address of the peer * (represented by INADDR_ANY). These are always arranged so that the * missing end is "that" (there can only be one missing end). These can * be instantiated (turned into real connections) by Pluto in one of two * different ways: Road Warrior Instantiation or Opportunistic * Instantiation. A template connection is marked for Opportunistic * Instantiation by specifying the peer client as 0.0.0.0/32 (or the IPV6 * equivalent). Otherwise, it is suitable for Road Warrior Instantiation. * * Instantiation creates a new temporary connection, with the missing * details filled in. The resulting template lasts only as long as there * is a state that uses it. */ /* connection policy priority: how important this policy is * - used to implement eroute-like precedence (augmented by a small * bonus for a routed connection). * - a whole number * - larger is more important * - three subcomponents. In order of decreasing significance: * + length of source subnet mask (8 bits) * + length of destination subnet mask (8 bits) * + bias (8 bit) * - a bias of 1 is added to allow prio BOTTOM_PRIO to be less than all * normal priorities * - other bias values are created on the fly to give mild preference * to certaion conditions (eg. routedness) * - priority is inherited -- an instance of a policy has the same priority * as the original policy, even though its subnets might be smaller. * - display format: n,m */ typedef unsigned long policy_prio_t; #define BOTTOM_PRIO ((policy_prio_t)0) /* smaller than any real prio */ #define set_policy_prio(c) { (c)->prio = \ ((policy_prio_t)(c)->spd.this.client.maskbits << 16) \ | ((policy_prio_t)(c)->spd.that.client.maskbits << 8) \ | (policy_prio_t)1; } #define POLICY_PRIO_BUF (3+1+3+1) extern void fmt_policy_prio(policy_prio_t pp, char buf[POLICY_PRIO_BUF]); struct virtual_t; struct end { identification_t *id; ip_address host_addr, host_nexthop; host_t *host_srcip; ip_subnet client; bool is_left; bool key_from_DNS_on_demand; bool has_client; bool has_client_wildcard; bool has_port_wildcard; bool has_id_wildcards; bool has_natip; char *updown; u_int16_t host_port; /* host order */ u_int16_t port; /* host order */ u_int8_t protocol; cert_t *cert; /* end certificate */ identification_t *ca; /* CA distinguished name */ ietf_attributes_t *groups; /* access control groups */ smartcard_t *sc; /* smartcard reader and key info */ struct virtual_t *virt; bool modecfg; /* this end: request local address from server */ /* that end: give local addresses to clients */ char *pool; /* name of an associated virtual IP address pool */ bool hostaccess; /* allow access to host via iptables INPUT/OUTPUT */ /* rules if client behind host is a subnet */ bool allow_any; /* IP address is subject to change */ certpolicy_t sendcert; /* whether or not to send the certificate */ }; struct spd_route { struct spd_route *next; struct end this; struct end that; so_serial_t eroute_owner; enum routing_t routing; /* level of routing in place */ uint32_t reqid; }; typedef struct connection connection_t; struct connection { char *name; bool ikev1; lset_t policy; time_t sa_ike_life_seconds; time_t sa_ipsec_life_seconds; time_t sa_rekey_margin; unsigned long sa_rekey_fuzz; unsigned long sa_keying_tries; /* RFC 3706 DPD */ time_t dpd_delay; time_t dpd_timeout; dpd_action_t dpd_action; char *log_file_name; /* name of log file */ FILE *log_file; /* possibly open FILE */ TAILQ_ENTRY(connection) log_link; /* linked list of open conns */ bool log_file_err; /* only bitch once */ struct spd_route spd; /* internal fields: */ unsigned long instance_serial; policy_prio_t prio; bool instance_initiation_ok; /* this is an instance of a policy that mandates initiate */ enum connection_kind kind; const struct iface *interface; /* filled in iff oriented */ so_serial_t /* state object serial number */ newest_isakmp_sa, newest_ipsec_sa; #ifdef DEBUG lset_t extra_debugging; #endif /* note: if the client is the gateway, the following must be equal */ sa_family_t addr_family; /* between gateways */ sa_family_t tunnel_addr_family; /* between clients */ connection_t *policy_next; /* if multiple policies, next one to apply */ struct gw_info *gw_info; struct alg_info_esp *alg_info_esp; struct alg_info_ike *alg_info_ike; struct host_pair *host_pair; connection_t *hp_next; /* host pair list link */ connection_t *ac_next; /* all connections list link */ linked_list_t *requested_ca; /* collected certificate requests */ linked_list_t *requested; /* requested attributes with handlers */ linked_list_t *attributes; /* configuration attributes with handlers */ bool got_certrequest; }; #define oriented(c) ((c).interface != NULL) extern bool orient(connection_t *c); extern bool same_peer_ids(const connection_t *c, const connection_t *d, identification_t *his_id); /* Format the topology of a connection end, leaving out defaults. * Largest left end looks like: client === host : port [ host_id ] --- hop * Note: if that==NULL, skip nexthop */ #define END_BUF (SUBNETTOT_BUF + ADDRTOT_BUF + IDTOA_BUF + ADDRTOT_BUF + 10) extern size_t format_end(char *buf, size_t buf_len, const struct end *this, const struct end *that, bool is_left, lset_t policy); extern void add_connection(const whack_message_t *wm); extern void initiate_connection(const char *name, int whackfd); extern void initiate_opportunistic(const ip_address *our_client, const ip_address *peer_client, int transport_proto, bool held, int whackfd); extern void terminate_connection(const char *nm); extern void release_connection(connection_t *c, bool relations); extern void delete_connection(connection_t *c, bool relations); extern void delete_connections_by_name(const char *name, bool strict); extern void delete_every_connection(void); extern char *add_group_instance(connection_t *group, const ip_subnet *target); extern void remove_group_instance(const connection_t *group, const char *name); extern void release_dead_interfaces(void); extern void check_orientations(void); extern connection_t *route_owner(connection_t *c, struct spd_route **srp, connection_t **erop, struct spd_route **esrp); extern connection_t *shunt_owner(const ip_subnet *ours, const ip_subnet *his); extern bool uniqueIDs; /* --uniqueids? */ extern void ISAKMP_SA_established(connection_t *c, so_serial_t serial); #define id_is_ipaddr(id) ((id)->get_type(id) == ID_IPV4_ADDR || \ (id)->get_type(id) == ID_IPV6_ADDR) extern bool his_id_was_instantiated(const connection_t *c); struct state; /* forward declaration of tag (defined in state.h) */ extern connection_t* con_by_name(const char *nm, bool strict); extern connection_t* find_host_connection(const ip_address *me, u_int16_t my_port, const ip_address *him, u_int16_t his_port, lset_t policy); extern connection_t* refine_host_connection(const struct state *st, identification_t *id, identification_t *peer_ca); extern connection_t* find_client_connection(connection_t *c, const ip_subnet *our_net, const ip_subnet *peer_net, const u_int8_t our_protocol, const u_int16_t out_port, const u_int8_t peer_protocol, const u_int16_t peer_port); extern connection_t* find_connection_by_reqid(uint32_t reqid); extern connection_t* find_connection_for_clients(struct spd_route **srp, const ip_address *our_client, const ip_address *peer_client, int transport_proto); extern void get_peer_ca_and_groups(connection_t *c, identification_t **peer_ca, ietf_attributes_t **peer_attributes); /* instantiating routines * Note: connection_discard() is in state.h because all its work * is looking through state objects. */ struct gw_info; /* forward declaration of tag (defined in dnskey.h) */ struct alg_info; /* forward declaration of tag (defined in alg_info.h) */ extern connection_t *rw_instantiate(connection_t *c, const ip_address *him, u_int16_t his_port, const ip_subnet *his_net, identification_t *his_id); extern connection_t *oppo_instantiate(connection_t *c, const ip_address *him, identification_t *his_id, struct gw_info *gw, const ip_address *our_client, const ip_address *peer_client); extern connection_t *build_outgoing_opportunistic_connection(struct gw_info *gw, const ip_address *our_client, const ip_address *peer_client); #define CONN_INST_BUF BUF_LEN extern void fmt_conn_instance(const connection_t *c, char buf[CONN_INST_BUF]); /* operations on "pending", the structure representing Quick Mode * negotiations delayed until a Keying Channel has been negotiated. */ struct pending; /* forward declaration (opaque outside connections.c) */ extern void add_pending(int whack_sock, struct state *isakmp_sa, connection_t *c, lset_t policy, unsigned long try, so_serial_t replacing); extern void release_pending_whacks(struct state *st, err_t story); extern void unpend(struct state *st); extern void update_pending(struct state *os, struct state *ns); extern void flush_pending_by_state(struct state *st); extern void show_pending_phase2(const struct host_pair *hp, const struct state *st); extern void connection_discard(connection_t *c); /* A template connection's eroute can be eclipsed by * either a %hold or an eroute for an instance iff * the template is a /32 -> /32. This requires some special casing. */ #define eclipsable(sr) (subnetishost(&(sr)->this.client) && subnetishost(&(sr)->that.client)) extern long eclipse_count; extern connection_t *eclipsed(connection_t *c, struct spd_route **); /* print connection status */ extern void show_connections_status(bool all, const char *name); extern int connection_compare(const connection_t *ca , const connection_t *cb); extern void update_host_pair(const char *why, connection_t *c , const ip_address *myaddr, u_int16_t myport , const ip_address *hisaddr, u_int16_t hisport); #endif /* _CONNECTIONS_H */