bird/nest/protocol.h
2016-05-12 18:03:23 +02:00

576 lines
23 KiB
C

/*
* BIRD Internet Routing Daemon -- Protocols
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
*
* 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 "sysdep/unix/timer.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
*/
struct protocol {
node n;
char *name;
char *template; /* Template for automatic generation of names */
int name_counter; /* Counter for automatic name generation */
int attr_class; /* Attribute class known to this protocol */
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, struct ea_list *attrs); /* 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) */
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);
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_ospf, proto_pipe, proto_bgp, proto_bfd, proto_babel;
/*
* 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 */
char *name;
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 */
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) */
/* 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 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 */
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 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 */
bird_clock_t last_state_change; /* Time of last state transition */
char *last_state_name_announced; /* Last state name we've announced to the user */
/*
* 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 Construct ea_list from private attrs stored in rte.
* store_tmp_attrs Store private attrs back to the rte.
* import_control Called as the first step of the route importing process.
* It can construct a new rte, add private attributes and
* decide whether the route shall be imported: 1=yes, -1=no,
* 0=process it through the import 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, struct ea_list *attrs);
void (*neigh_notify)(struct neighbor *neigh);
struct ea_list *(*make_tmp_attrs)(struct rte *rt, struct linpool *pool);
void (*store_tmp_attrs)(struct rte *rt, struct ea_list *attrs);
int (*import_control)(struct proto *, struct rte **rt, struct ea_list **attrs, 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 *);
void (*rte_insert)(struct network *, struct rte *);
void (*rte_remove)(struct network *, struct rte *);
/* Hic sunt protocol-specific data */
};
struct proto_spec {
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_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 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 proto_cmd_show(struct proto *, uint, int);
void proto_cmd_disable(struct proto *, uint, int);
void proto_cmd_enable(struct proto *, uint, int);
void proto_cmd_restart(struct proto *, uint, int);
void proto_cmd_reload(struct proto *, uint, int);
void proto_cmd_debug(struct proto *, uint, int);
void proto_cmd_mrtdump(struct proto *, uint, int);
void proto_apply_cmd(struct proto_spec ps, void (* cmd)(struct proto *, uint, int), int restricted, uint arg);
struct proto *proto_get_named(struct symbol *, struct protocol *);
#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;
}
/* Moved from route.h to avoid dependency conflicts */
static inline void rte_update(struct proto *p, net_addr *n, rte *new) { rte_update2(p->main_channel, n, new, p->main_source); }
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 */
struct channel * (*init)(struct channel *, struct channel_config *); /* Create new instance */
int (*reconfigure)(struct channel *, struct channel_config *); /* Try to reconfigure instance, returns success */
int (*start)(struct channel *); /* Start the instance */
int (*shutdown)(struct channel *); /* Stop the instance */
void (*copy_config)(struct channel_config *, struct channel_config *); /* Copy config from given channel instance */
#if 0
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 (*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, struct ea_list *attrs); /* 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
};
struct channel_config {
node n;
const char *name;
const struct channel_class *channel;
struct rtable_config *table; /* Table we're attached to */
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 */
u8 merge_limit; /* Maximal number of nexthops for RA_MERGED */
u8 in_keep_filtered; /* Routes rejected in import filter are kept */
};
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;
struct filter *in_filter; /* Input filter */
struct filter *out_filter; /* Output 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 */
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 */
u8 merge_limit; /* Maximal number of nexthops for RA_MERGED */
u8 in_keep_filtered; /* Routes rejected in import filter are kept */
u8 disabled;
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 */
bird_clock_t last_state_change; /* Time of last state transition */
};
/*
* 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_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);
/*
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, uint net_type, struct proto_config *proto);
int channel_reconfigure(struct channel *c, struct channel_config *cf);
#endif