/* * BIRD Internet Routing Daemon -- Protocols * * (c) 1998--2000 Martin Mares * * Can be freely distributed and used under the terms of the GNU GPL. */ #ifndef _BIRD_PROTOCOL_H_ #define _BIRD_PROTOCOL_H_ #include "lib/lists.h" #include "lib/resource.h" #include "lib/event.h" #include "nest/route.h" #include "conf/conf.h" struct iface; struct ifa; struct rtable; struct rte; struct neighbor; struct rta; struct network; struct proto_config; struct channel_limit; struct channel_config; struct config; struct proto; struct channel; struct ea_list; struct eattr; struct symbol; /* * Routing Protocol */ enum protocol_class { PROTOCOL_NONE, PROTOCOL_BABEL, PROTOCOL_BFD, PROTOCOL_BGP, PROTOCOL_DEVICE, PROTOCOL_DIRECT, PROTOCOL_KERNEL, PROTOCOL_OSPF, PROTOCOL_MRT, PROTOCOL_PERF, PROTOCOL_PIPE, PROTOCOL_RADV, PROTOCOL_RIP, PROTOCOL_RPKI, PROTOCOL_STATIC, PROTOCOL__MAX }; extern struct protocol *class_to_protocol[PROTOCOL__MAX]; struct protocol { node n; char *name; char *template; /* Template for automatic generation of names */ int name_counter; /* Counter for automatic name generation */ enum protocol_class class; /* Machine readable protocol class */ uint preference; /* Default protocol preference */ uint channel_mask; /* Mask of accepted channel types (NB_*) */ uint proto_size; /* Size of protocol data structure */ uint config_size; /* Size of protocol config data structure */ void (*preconfig)(struct protocol *, struct config *); /* Just before configuring */ void (*postconfig)(struct proto_config *); /* After configuring each instance */ struct proto * (*init)(struct proto_config *); /* Create new instance */ int (*reconfigure)(struct proto *, struct proto_config *); /* Try to reconfigure instance, returns success */ void (*dump)(struct proto *); /* Debugging dump */ void (*dump_attrs)(struct rte *); /* Dump protocol-dependent attributes */ int (*start)(struct proto *); /* Start the instance */ int (*shutdown)(struct proto *); /* Stop the instance */ void (*cleanup)(struct proto *); /* Called after shutdown when protocol became hungry/down */ void (*get_status)(struct proto *, byte *buf); /* Get instance status (for `show protocols' command) */ void (*get_route_info)(struct rte *, byte *buf); /* Get route information (for `show route' command) */ int (*get_attr)(const struct eattr *, byte *buf, int buflen); /* ASCIIfy dynamic attribute (returns GA_*) */ void (*show_proto_info)(struct proto *); /* Show protocol info (for `show protocols all' command) */ void (*copy_config)(struct proto_config *, struct proto_config *); /* Copy config from given protocol instance */ }; void protos_build(void); void proto_build(struct protocol *); void protos_preconfig(struct config *); void protos_commit(struct config *new, struct config *old, int force_restart, int type); struct proto * proto_spawn(struct proto_config *cf, uint disabled); void protos_dump_all(void); #define GA_UNKNOWN 0 /* Attribute not recognized */ #define GA_NAME 1 /* Result = name */ #define GA_FULL 2 /* Result = both name and value */ /* * Known protocols */ extern struct protocol proto_device, proto_radv, proto_rip, proto_static, proto_mrt, proto_ospf, proto_perf, proto_pipe, proto_bgp, proto_bfd, proto_babel, proto_rpki; /* * Routing Protocol Instance */ struct proto_config { node n; struct config *global; /* Global configuration data */ struct protocol *protocol; /* Protocol */ struct proto *proto; /* Instance we've created */ struct proto_config *parent; /* Parent proto_config for dynamic protocols */ const char *name; const char *dsc; int class; /* SYM_PROTO or SYM_TEMPLATE */ u8 net_type; /* Protocol network type (NET_*), 0 for undefined */ u8 disabled; /* Protocol enabled/disabled by default */ u8 vrf_set; /* Related VRF instance (below) is defined */ u32 debug, mrtdump; /* Debugging bitfields, both use D_* constants */ u32 router_id; /* Protocol specific router ID */ list channels; /* List of channel configs (struct channel_config) */ struct iface *vrf; /* Related VRF instance, NULL if global */ /* Check proto_reconfigure() and proto_copy_config() after changing struct proto_config */ /* Protocol-specific data follow... */ }; /* Protocol statistics */ struct proto_stats { /* Import - from protocol to core */ u32 imp_routes; /* Number of routes successfully imported to the (adjacent) routing table */ u32 filt_routes; /* Number of routes rejected in import filter but kept in the routing table */ u32 pref_routes; /* Number of routes selected as best in the (adjacent) routing table */ u32 imp_updates_received; /* Number of route updates received */ u32 imp_updates_invalid; /* Number of route updates rejected as invalid */ u32 imp_updates_filtered; /* Number of route updates rejected by filters */ u32 imp_updates_ignored; /* Number of route updates rejected as already in route table */ u32 imp_updates_accepted; /* Number of route updates accepted and imported */ u32 imp_withdraws_received; /* Number of route withdraws received */ u32 imp_withdraws_invalid; /* Number of route withdraws rejected as invalid */ u32 imp_withdraws_ignored; /* Number of route withdraws rejected as already not in route table */ u32 imp_withdraws_accepted; /* Number of route withdraws accepted and processed */ /* Export - from core to protocol */ u32 exp_routes; /* Number of routes successfully exported to the protocol */ u32 exp_updates_received; /* Number of route updates received */ u32 exp_updates_rejected; /* Number of route updates rejected by protocol */ u32 exp_updates_filtered; /* Number of route updates rejected by filters */ u32 exp_updates_accepted; /* Number of route updates accepted and exported */ u32 exp_withdraws_received; /* Number of route withdraws received */ u32 exp_withdraws_accepted; /* Number of route withdraws accepted and processed */ }; struct proto { node n; /* Node in global proto_list */ struct protocol *proto; /* Protocol */ struct proto_config *cf; /* Configuration data */ struct proto_config *cf_new; /* Configuration we want to switch to after shutdown (NULL=delete) */ pool *pool; /* Pool containing local objects */ event *event; /* Protocol event */ list channels; /* List of channels to rtables (struct channel) */ struct channel *main_channel; /* Primary channel */ struct rte_src *main_source; /* Primary route source */ struct iface *vrf; /* Related VRF instance, NULL if global */ const char *name; /* Name of this instance (== cf->name) */ u32 debug; /* Debugging flags */ u32 mrtdump; /* MRTDump flags */ uint active_channels; /* Number of active channels */ byte net_type; /* Protocol network type (NET_*), 0 for undefined */ byte disabled; /* Manually disabled */ byte vrf_set; /* Related VRF instance (above) is defined */ byte proto_state; /* Protocol state machine (PS_*, see below) */ byte active; /* From PS_START to cleanup after PS_STOP */ byte do_start; /* Start actions are scheduled */ byte do_stop; /* Stop actions are scheduled */ byte reconfiguring; /* We're shutting down due to reconfiguration */ byte gr_recovery; /* Protocol should participate in graceful restart recovery */ byte down_sched; /* Shutdown is scheduled for later (PDS_*) */ byte down_code; /* Reason for shutdown (PDC_* codes) */ u32 hash_key; /* Random key used for hashing of neighbors */ btime last_state_change; /* Time of last state transition */ char *last_state_name_announced; /* Last state name we've announced to the user */ char *message; /* State-change message, allocated from proto_pool */ /* * General protocol hooks: * * if_notify Notify protocol about interface state changes. * ifa_notify Notify protocol about interface address changes. * rt_notify Notify protocol about routing table updates. * neigh_notify Notify protocol about neighbor cache events. * make_tmp_attrs Add attributes to rta from from private attrs stored in rte. The route and rta MUST NOT be cached. * store_tmp_attrs Store private attrs back to rte and undef added attributes. The route and rta MUST NOT be cached. * preexport Called as the first step of the route exporting process. * It can construct a new rte, add private attributes and * decide whether the route shall be exported: 1=yes, -1=no, * 0=process it through the export filter set by the user. * reload_routes Request channel to reload all its routes to the core * (using rte_update()). Returns: 0=reload cannot be done, * 1= reload is scheduled and will happen (asynchronously). * feed_begin Notify channel about beginning of route feeding. * feed_end Notify channel about finish of route feeding. */ void (*if_notify)(struct proto *, unsigned flags, struct iface *i); void (*ifa_notify)(struct proto *, unsigned flags, struct ifa *a); void (*rt_notify)(struct proto *, struct channel *, struct network *net, struct rte *new, struct rte *old); void (*neigh_notify)(struct neighbor *neigh); void (*make_tmp_attrs)(struct rte *rt, struct linpool *pool); void (*store_tmp_attrs)(struct rte *rt, struct linpool *pool); int (*preexport)(struct proto *, struct rte **rt, struct linpool *pool); void (*reload_routes)(struct channel *); void (*feed_begin)(struct channel *, int initial); void (*feed_end)(struct channel *); /* * Routing entry hooks (called only for routes belonging to this protocol): * * rte_recalculate Called at the beginning of the best route selection * rte_better Compare two rte's and decide which one is better (1=first, 0=second). * rte_same Compare two rte's and decide whether they are identical (1=yes, 0=no). * rte_mergable Compare two rte's and decide whether they could be merged (1=yes, 0=no). * rte_insert Called whenever a rte is inserted to a routing table. * rte_remove Called whenever a rte is removed from the routing table. */ int (*rte_recalculate)(struct rtable *, struct network *, struct rte *, struct rte *, struct rte *); int (*rte_better)(struct rte *, struct rte *); int (*rte_same)(struct rte *, struct rte *); int (*rte_mergable)(struct rte *, struct rte *); struct rte * (*rte_modify)(struct rte *, struct linpool *); void (*rte_insert)(struct network *, struct rte *); void (*rte_remove)(struct network *, struct rte *); /* Hic sunt protocol-specific data */ }; struct proto_spec { const void *ptr; int patt; }; #define PDS_DISABLE 1 /* Proto disable scheduled */ #define PDS_RESTART 2 /* Proto restart scheduled */ #define PDC_CF_REMOVE 0x01 /* Removed in new config */ #define PDC_CF_DISABLE 0x02 /* Disabled in new config */ #define PDC_CF_RESTART 0x03 /* Restart due to reconfiguration */ #define PDC_CMD_DISABLE 0x11 /* Result of disable command */ #define PDC_CMD_RESTART 0x12 /* Result of restart command */ #define PDC_CMD_SHUTDOWN 0x13 /* Result of global shutdown */ #define PDC_CMD_GR_DOWN 0x14 /* Result of global graceful restart */ #define PDC_RX_LIMIT_HIT 0x21 /* Route receive limit reached */ #define PDC_IN_LIMIT_HIT 0x22 /* Route import limit reached */ #define PDC_OUT_LIMIT_HIT 0x23 /* Route export limit reached */ void *proto_new(struct proto_config *); void *proto_config_new(struct protocol *, int class); void proto_copy_config(struct proto_config *dest, struct proto_config *src); void proto_clone_config(struct symbol *sym, struct proto_config *parent); void proto_set_message(struct proto *p, char *msg, int len); void graceful_restart_recovery(void); void graceful_restart_init(void); void graceful_restart_show_status(void); void channel_graceful_restart_lock(struct channel *c); void channel_graceful_restart_unlock(struct channel *c); #define DEFAULT_GR_WAIT 240 void channel_show_limit(struct channel_limit *l, const char *dsc); void channel_show_info(struct channel *c); void channel_cmd_debug(struct channel *c, uint mask); void proto_cmd_show(struct proto *, uintptr_t, int); void proto_cmd_disable(struct proto *, uintptr_t, int); void proto_cmd_enable(struct proto *, uintptr_t, int); void proto_cmd_restart(struct proto *, uintptr_t, int); void proto_cmd_reload(struct proto *, uintptr_t, int); void proto_cmd_debug(struct proto *, uintptr_t, int); void proto_cmd_mrtdump(struct proto *, uintptr_t, int); void proto_apply_cmd(struct proto_spec ps, void (* cmd)(struct proto *, uintptr_t, int), int restricted, uintptr_t arg); struct proto *proto_get_named(struct symbol *, struct protocol *); struct proto *proto_iterate_named(struct symbol *sym, struct protocol *proto, struct proto *old); #define PROTO_WALK_CMD(sym,pr,p) for(struct proto *p = NULL; p = proto_iterate_named(sym, pr, p); ) #define CMD_RELOAD 0 #define CMD_RELOAD_IN 1 #define CMD_RELOAD_OUT 2 static inline u32 proto_get_router_id(struct proto_config *pc) { return pc->router_id ? pc->router_id : pc->global->router_id; } extern pool *proto_pool; extern list proto_list; /* * Each protocol instance runs two different state machines: * * [P] The protocol machine: (implemented inside protocol) * * DOWN ----> START * ^ | * | V * STOP <---- UP * * States: DOWN Protocol is down and it's waiting for the core * requesting protocol start. * START Protocol is waiting for connection with the rest * of the network and it's not willing to accept * packets. When it connects, it goes to UP state. * UP Protocol is up and running. When the network * connection breaks down or the core requests * protocol to be terminated, it goes to STOP state. * STOP Protocol is disconnecting from the network. * After it disconnects, it returns to DOWN state. * * In: start() Called in DOWN state to request protocol startup. * Returns new state: either UP or START (in this * case, the protocol will notify the core when it * finally comes UP). * stop() Called in START, UP or STOP state to request * protocol shutdown. Returns new state: either * DOWN or STOP (in this case, the protocol will * notify the core when it finally comes DOWN). * * Out: proto_notify_state() -- called by protocol instance when * it does any state transition not covered by * return values of start() and stop(). This includes * START->UP (delayed protocol startup), UP->STOP * (spontaneous shutdown) and STOP->DOWN (delayed * shutdown). */ #define PS_DOWN 0 #define PS_START 1 #define PS_UP 2 #define PS_STOP 3 void proto_notify_state(struct proto *p, unsigned state); /* * [F] The feeder machine: (implemented in core routines) * * HUNGRY ----> FEEDING * ^ | * | V * FLUSHING <---- HAPPY * * States: HUNGRY Protocol either administratively down (i.e., * disabled by the user) or temporarily down * (i.e., [P] is not UP) * FEEDING The protocol came up and we're feeding it * initial routes. [P] is UP. * HAPPY The protocol is up and it's receiving normal * routing updates. [P] is UP. * FLUSHING The protocol is down and we're removing its * routes from the table. [P] is STOP or DOWN. * * Normal lifecycle of a protocol looks like: * * HUNGRY/DOWN --> HUNGRY/START --> HUNGRY/UP --> * FEEDING/UP --> HAPPY/UP --> FLUSHING/STOP|DOWN --> * HUNGRY/STOP|DOWN --> HUNGRY/DOWN * * Sometimes, protocol might switch from HAPPY/UP to FEEDING/UP * if it wants to refeed the routes (for example BGP does so * as a result of received ROUTE-REFRESH request). */ /* * Debugging flags */ #define D_STATES 1 /* [core] State transitions */ #define D_ROUTES 2 /* [core] Routes passed by the filters */ #define D_FILTERS 4 /* [core] Routes rejected by the filters */ #define D_IFACES 8 /* [core] Interface events */ #define D_EVENTS 16 /* Protocol events */ #define D_PACKETS 32 /* Packets sent/received */ #ifndef PARSER #define TRACE(flags, msg, args...) \ do { if (p->p.debug & flags) log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0) #endif /* * MRTDump flags */ #define MD_STATES 1 /* Protocol state changes (BGP4MP_MESSAGE_AS4) */ #define MD_MESSAGES 2 /* Protocol packets (BGP4MP_MESSAGE_AS4) */ /* * Known unique protocol instances as referenced by config routines */ extern struct proto_config *cf_dev_proto; /* * Protocol limits */ #define PLD_RX 0 /* Receive limit */ #define PLD_IN 1 /* Import limit */ #define PLD_OUT 2 /* Export limit */ #define PLD_MAX 3 #define PLA_NONE 0 /* No limit */ #define PLA_WARN 1 /* Issue log warning */ #define PLA_BLOCK 2 /* Block new routes */ #define PLA_RESTART 4 /* Force protocol restart */ #define PLA_DISABLE 5 /* Shutdown and disable protocol */ #define PLS_INITIAL 0 /* Initial limit state after protocol start */ #define PLS_ACTIVE 1 /* Limit was hit */ #define PLS_BLOCKED 2 /* Limit is active and blocking new routes */ struct channel_limit { u32 limit; /* Maximum number of prefixes */ u8 action; /* Action to take (PLA_*) */ u8 state; /* State of limit (PLS_*) */ }; void channel_notify_limit(struct channel *c, struct channel_limit *l, int dir, u32 rt_count); /* * Channels */ struct channel_class { uint channel_size; /* Size of channel data structure */ uint config_size; /* Size of channel config data structure */ void (*init)(struct channel *, struct channel_config *); /* Create new instance */ int (*reconfigure)(struct channel *, struct channel_config *, int *import_changed, int *export_changed); /* Try to reconfigure instance, returns success */ int (*start)(struct channel *); /* Start the instance */ void (*shutdown)(struct channel *); /* Stop the instance */ void (*cleanup)(struct channel *); /* Channel finished flush */ void (*copy_config)(struct channel_config *, struct channel_config *); /* Copy config from given channel instance */ #if 0 XXXX; void (*preconfig)(struct protocol *, struct config *); /* Just before configuring */ void (*postconfig)(struct proto_config *); /* After configuring each instance */ void (*dump)(struct proto *); /* Debugging dump */ void (*dump_attrs)(struct rte *); /* Dump protocol-dependent attributes */ void (*get_status)(struct proto *, byte *buf); /* Get instance status (for `show protocols' command) */ void (*get_route_info)(struct rte *, byte *buf); /* Get route information (for `show route' command) */ int (*get_attr)(struct eattr *, byte *buf, int buflen); /* ASCIIfy dynamic attribute (returns GA_*) */ void (*show_proto_info)(struct proto *); /* Show protocol info (for `show protocols all' command) */ #endif }; extern struct channel_class channel_bgp; struct channel_config { node n; const char *name; const struct channel_class *channel; struct proto_config *parent; /* Where channel is defined (proto or template) */ struct rtable_config *table; /* Table we're attached to */ const struct filter *in_filter, *out_filter; /* Attached filters */ struct channel_limit rx_limit; /* Limit for receiving routes from protocol (relevant when in_keep_filtered is active) */ struct channel_limit in_limit; /* Limit for importing routes from protocol */ struct channel_limit out_limit; /* Limit for exporting routes to protocol */ u8 net_type; /* Routing table network type (NET_*), 0 for undefined */ u8 ra_mode; /* Mode of received route advertisements (RA_*) */ u16 preference; /* Default route preference */ u32 debug; /* Debugging flags (D_*) */ u8 merge_limit; /* Maximal number of nexthops for RA_MERGED */ u8 in_keep_filtered; /* Routes rejected in import filter are kept */ u8 rpki_reload; /* RPKI changes trigger channel reload */ }; struct channel { node n; /* Node in proto->channels */ node table_node; /* Node in table->channels */ const char *name; /* Channel name (may be NULL) */ const struct channel_class *channel; struct proto *proto; struct rtable *table; const struct filter *in_filter; /* Input filter */ const struct filter *out_filter; /* Output filter */ struct bmap export_map; /* Keeps track which routes passed export filter */ struct channel_limit rx_limit; /* Receive limit (for in_keep_filtered) */ struct channel_limit in_limit; /* Input limit */ struct channel_limit out_limit; /* Output limit */ struct event *feed_event; /* Event responsible for feeding */ struct fib_iterator feed_fit; /* Routing table iterator used during feeding */ struct proto_stats stats; /* Per-channel protocol statistics */ u32 refeed_count; /* Number of routes exported during refeed regardless of out_limit */ u8 net_type; /* Routing table network type (NET_*), 0 for undefined */ u8 ra_mode; /* Mode of received route advertisements (RA_*) */ u16 preference; /* Default route preference */ u32 debug; /* Debugging flags (D_*) */ u8 merge_limit; /* Maximal number of nexthops for RA_MERGED */ u8 in_keep_filtered; /* Routes rejected in import filter are kept */ u8 disabled; u8 stale; /* Used in reconfiguration */ u8 channel_state; u8 export_state; /* Route export state (ES_*, see below) */ u8 feed_active; u8 flush_active; u8 refeeding; /* We are refeeding (valid only if export_state == ES_FEEDING) */ u8 reloadable; /* Hook reload_routes() is allowed on the channel */ u8 gr_lock; /* Graceful restart mechanism should wait for this channel */ u8 gr_wait; /* Route export to channel is postponed until graceful restart */ btime last_state_change; /* Time of last state transition */ struct rtable *in_table; /* Internal table for received routes */ struct event *reload_event; /* Event responsible for reloading from in_table */ struct fib_iterator reload_fit; /* FIB iterator in in_table used during reloading */ struct rte *reload_next_rte; /* Route iterator in in_table used during reloading */ u8 reload_active; /* Iterator reload_fit is linked */ u8 reload_pending; /* Reloading and another reload is scheduled */ u8 refeed_pending; /* Refeeding and another refeed is scheduled */ u8 rpki_reload; /* RPKI changes trigger channel reload */ struct rtable *out_table; /* Internal table for exported routes */ list roa_subscriptions; /* List of active ROA table subscriptions based on filters roa_check() */ }; /* * Channel states * * CS_DOWN - The initial and the final state of a channel. There is no route * exchange between the protocol and the table. Channel is not counted as * active. Channel keeps a ptr to the table, but do not lock the table and is * not linked in the table. Generally, new closed channels are created in * protocols' init() hooks. The protocol is expected to explicitly activate its * channels (by calling channel_init() or channel_open()). * * CS_START - The channel as a connection between the protocol and the table is * initialized (counted as active by the protocol, linked in the table and keeps * the table locked), but there is no current route exchange. There still may be * routes associated with the channel in the routing table if the channel falls * to CS_START from CS_UP. Generally, channels are initialized in protocols' * start() hooks when going to PS_START. * * CS_UP - The channel is initialized and the route exchange is allowed. Note * that even in CS_UP state, route export may still be down (ES_DOWN) by the * core decision (e.g. waiting for table convergence after graceful restart). * I.e., the protocol decides to open the channel but the core decides to start * route export. Route import (caused by rte_update() from the protocol) is not * restricted by that and is on volition of the protocol. Generally, channels * are opened in protocols' start() hooks when going to PS_UP. * * CS_FLUSHING - The transitional state between initialized channel and closed * channel. The channel is still initialized, but no route exchange is allowed. * Instead, the associated table is running flush loop to remove routes imported * through the channel. After that, the channel changes state to CS_DOWN and * is detached from the table (the table is unlocked and the channel is unlinked * from it). Unlike other states, the CS_FLUSHING state is not explicitly * entered or left by the protocol. A protocol may request to close a channel * (by calling channel_close()), which causes the channel to change state to * CS_FLUSHING and later to CS_DOWN. Also note that channels are closed * automatically by the core when the protocol is going down. * * Allowed transitions: * * CS_DOWN -> CS_START / CS_UP * CS_START -> CS_UP / CS_FLUSHING * CS_UP -> CS_START / CS_FLUSHING * CS_FLUSHING -> CS_DOWN (automatic) */ #define CS_DOWN 0 #define CS_START 1 #define CS_UP 2 #define CS_FLUSHING 3 #define ES_DOWN 0 #define ES_FEEDING 1 #define ES_READY 2 struct channel_config *proto_cf_find_channel(struct proto_config *p, uint net_type); static inline struct channel_config *proto_cf_main_channel(struct proto_config *pc) { struct channel_config *cc = HEAD(pc->channels); return NODE_VALID(cc) ? cc : NULL; } struct channel *proto_find_channel_by_table(struct proto *p, struct rtable *t); struct channel *proto_find_channel_by_name(struct proto *p, const char *n); struct channel *proto_add_channel(struct proto *p, struct channel_config *cf); int proto_configure_channel(struct proto *p, struct channel **c, struct channel_config *cf); void channel_set_state(struct channel *c, uint state); void channel_setup_in_table(struct channel *c); void channel_setup_out_table(struct channel *c); void channel_schedule_reload(struct channel *c); static inline void channel_init(struct channel *c) { channel_set_state(c, CS_START); } static inline void channel_open(struct channel *c) { channel_set_state(c, CS_UP); } static inline void channel_close(struct channel *c) { channel_set_state(c, CS_FLUSHING); } void channel_request_feeding(struct channel *c); void *channel_config_new(const struct channel_class *cc, const char *name, uint net_type, struct proto_config *proto); void *channel_config_get(const struct channel_class *cc, const char *name, uint net_type, struct proto_config *proto); int channel_reconfigure(struct channel *c, struct channel_config *cf); #endif