eigrp_structs.h

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * EIGRP Definition of Data Structures.
 * Copyright (C) 2013-2016
 * Authors:
 *   Donnie Savage
 *   Jan Janovic
 *   Matej Perina
 *   Peter Orsag
 *   Peter Paluch
 *   Frantisek Gazo
 *   Tomas Hvorkovy
 *   Martin Kontsek
 *   Lukas Koribsky
 *
 */

#ifndef _ZEBRA_EIGRP_STRUCTS_H_
#define _ZEBRA_EIGRP_STRUCTS_H_

#include "eigrpd/eigrp_const.h"
#include "eigrpd/eigrp_types.h"
#include "eigrpd/eigrp_macros.h"

typedef struct eigrp_addr {
    uint8_t afi;		// ipv4 or ipv6
    union {
	struct in_addr  v4;
	struct in6_addr v6;
    } ip;
} eigrp_addr_t;
    
typedef struct eigrp_metrics {
	eigrp_delay_t delay;
	eigrp_bandwidth_t bandwidth;
	unsigned char mtu[3];
	uint8_t hop_count;
	uint8_t reliability;
	uint8_t load;
	uint8_t tag;
	uint8_t flags;
} eigrp_metrics_t;

typedef struct eigrp_extdata {
	uint32_t orig;
	uint32_t as;
	uint32_t tag;
	uint32_t metric;
	uint16_t reserved;
	uint8_t protocol;
	uint8_t flags;
} eigrp_extdata_t;

/*
 *DVS: this stuct is a mess of a dumping ground for any and everythign.
 *     will be cleaned up as it exposes to much to functions that do not need
 *it.
 *
 */
struct eigrp_instance {
	vrf_id_t vrf_id;

	uint16_t AS;	     /* Autonomous system number */
	uint16_t vrid;	     /* Virtual Router ID */
	uint8_t k_values[6]; /*Array for K values configuration*/
	uint8_t variance;    /*Metric variance multiplier*/
	uint8_t max_paths;   /*Maximum allowed paths for 1 prefix*/

	/*Name of this EIGRP instance*/
	char *name;

	/* EIGRP Router ID. */
	struct in_addr router_id;	 /* Configured automatically. */
	struct in_addr router_id_static; /* Configured manually. */

	struct list *eiflist;		   /* eigrp interfaces */
	uint8_t passive_interface_default; /* passive-interface default */

	int fd;
	unsigned int maxsndbuflen;

	uint32_t sequence_number; /*Global EIGRP sequence number*/

	struct stream *ibuf;
	struct list *oi_write_q;

	/*Events*/
	struct event *t_write;
	struct event *t_read;
	struct event *t_distribute; /* timer for distribute list */

	struct route_table *networks; /* EIGRP config networks. */

	struct route_table *topology_table;

	uint64_t serno; /* Global serial number counter for topology entry
			   changes*/
	uint64_t serno_last_update; /* Highest serial number of information send
				       by last update*/
	struct list *topology_changes;

	/*Neighbor self*/
	eigrp_neighbor_t *neighbor_self;

	/*Configured metric for redistributed routes*/
	eigrp_metrics_t dmetric[ZEBRA_ROUTE_MAX + 1];
	int redistribute; /* Num of redistributed protocols. */

	/* Access-list. */
	struct access_list *list[EIGRP_FILTER_MAX];
	/* Prefix-list. */
	struct prefix_list *prefix[EIGRP_FILTER_MAX];
	/* Route-map. */
	struct route_map *routemap[EIGRP_FILTER_MAX];

	/* For redistribute route map. */
	struct {
		char *name;
		struct route_map *map;
		int metric_config;
		uint32_t metric;
	} route_map[ZEBRA_ROUTE_MAX];

	/* distribute_ctx */
	struct distribute_ctx *distribute_ctx;

	QOBJ_FIELDS;
};
DECLARE_QOBJ_TYPE(eigrp);

typedef struct eigrp_packet_queue {
	eigrp_packet_t *head;
	eigrp_packet_t *tail;

	unsigned long count;
} eigrp_packet_queue_t;

typedef struct eigrp_intf_params {
	uint8_t passive_interface;
	uint32_t v_hello;
	uint16_t v_wait;
	uint8_t type; /* type of interface */
	uint32_t bandwidth;
	uint32_t delay;
	uint8_t reliability;
	uint8_t load;

	char *auth_keychain; /* Associated keychain with interface*/
	int auth_type;	     /* EIGRP authentication type */
} eigrp_intf_params_t;

enum { MEMBER_ALLROUTERS = 0,
       MEMBER_MAX,
};

typedef struct eigrp_intf_stats {
	struct {
		int ack;
		int hello;  /* Hello message input count. */
		int query;  /* Query message input count. */
		int reply;  /* Reply message input count. */
		int update; /* Update message input count. */
		int siaQuery;
		int siaReply;
	} rcvd;

	struct {
		int ack;
		int hello;  /* Hello message output count. */
		int query;  /* Query message output count. */
		int reply;  /* Reply message output count. */
		int update; /* Update message output count. */
		int siaQuery;
		int siaReply;
	} sent;
} eigrp_intf_stats_t;

/*EIGRP interface structure*/
typedef struct eigrp_interface {

	/* This interface's parent eigrp instance. */
	eigrp_instance_t *eigrp;

	/* Zebra Interface Properties */
	struct interface *ifp;	//Interface data from zebra
	uint8_t type;		// P2P, LOOP, BCAST
	struct prefix address;	// Interface prefix
	uint32_t curr_bandwidth;
	uint32_t curr_mtu;

	/* Multicat Properties */
	bool    member_allrouters;	// multicast group refcnts
	uint8_t multicast_memberships;	//  multicast groups we belong

	/* EIGRP Interface Properties */
	eigrp_intf_params_t params;
	struct {
		bool mixed;
		uint8_t v1;
		uint8_t v2;
	} version;

	/* Neighbor information. */
	struct list *nbrs; /* EIGRP Neighbor List */

	/* Events. */
	struct event *t_hello;	     /* timer */
	struct event *t_distribute; /* timer for distribute list */

	/* Packet send buffer. */
	eigrp_packet_queue_t *obuf; /* Output queue */
	int on_write_q;
	uint32_t crypt_seqnum; /* Cryptographic Sequence Number */

	/* Statistics fields. */
	eigrp_intf_stats_t stats; // Statistics fields

	/* Access-list. */
	struct access_list *list[EIGRP_FILTER_MAX];
	/* Prefix-list. */
	struct prefix_list *prefix[EIGRP_FILTER_MAX];
	/* Route-map. */
	struct route_map *routemap[EIGRP_FILTER_MAX];
} eigrp_interface_t;

/* Determines if it is first or last packet
 * when packet consists of multiple packet
 * chunks because of many route TLV
 * (all won't fit into one packet) */
enum Packet_part_type {
	EIGRP_PACKET_PART_NA,
	EIGRP_PACKET_PART_FIRST,
	EIGRP_PACKET_PART_LAST
};

//---------------------------------------------------------------------------------------------------------------------------------------------

typedef struct eigrp_packet {
	eigrp_packet_t *next;
	eigrp_packet_t *previous;

	/* Pointer to data stream. */
	struct stream *s;

	/* IP destination address. */
	eigrp_addr_t dst;

	/*Packet retransmission event and counter*/
	struct event *t_retrans_timer;
	uint8_t retrans_counter;

	/*neighbor details for sendng packet*/
	eigrp_neighbor_t *nbr;
	uint32_t sequence_number;

	/* EIGRP packet length. */
	uint16_t length;

} eigrp_packet_t;

struct eigrp_header {
	uint8_t version;
	uint8_t opcode;
	uint16_t checksum;
	uint32_t flags;
	uint32_t sequence;
	uint32_t ack;
	uint16_t vrid;
	uint16_t ASNumber;
	char *tlv[0];

} __attribute__((packed));

typedef struct eigrp_header eigrp_header_t;

/**
 * Generic TLV type used for packet decoding.
 *
 *      +-----+------------------+
 *      |     |     |            |
 *      | Type| Len |    Vector  |
 *      |     |     |            |
 *      +-----+------------------+
 */
struct eigrp_tlv_hdr_type {
	uint16_t type;
	uint16_t length;
	uint8_t value[0];
} __attribute__((packed));

struct TLV_Parameter_Type {
	uint16_t type;
	uint16_t length;
	uint8_t K1;
	uint8_t K2;
	uint8_t K3;
	uint8_t K4;
	uint8_t K5;
	uint8_t K6;
	uint16_t hold_time;
} __attribute__((packed));

struct TLV_MD5_Authentication_Type {
	uint16_t type;
	uint16_t length;
	uint16_t auth_type;
	uint16_t auth_length;
	uint32_t key_id;
	uint32_t key_sequence;
	uint8_t Nullpad[8];
	uint8_t digest[EIGRP_AUTH_TYPE_MD5_LEN];

} __attribute__((packed));

struct TLV_SHA256_Authentication_Type {
	uint16_t type;
	uint16_t length;
	uint16_t auth_type;
	uint16_t auth_length;
	uint32_t key_id;
	uint32_t key_sequence;
	uint8_t Nullpad[8];
	uint8_t digest[EIGRP_AUTH_TYPE_SHA256_LEN];

} __attribute__((packed));

struct TLV_Sequence_Type {
	uint16_t type;
	uint16_t length;
	uint8_t addr_length;
	struct in_addr *addresses;
} __attribute__((packed));

struct TLV_Next_Multicast_Sequence {
	uint16_t type;
	uint16_t length;
	uint32_t multicast_sequence;
} __attribute__((packed));

struct TLV_Software_Type {
	uint16_t type;
	uint16_t length;
	uint8_t vender_major;
	uint8_t vender_minor;
	uint8_t eigrp_major;
	uint8_t eigrp_minor;
} __attribute__((packed));

struct TLV_IPv4_Internal_type {
	uint16_t type;
	uint16_t length;
	struct in_addr forward;

	/*Metrics*/
	struct eigrp_metrics metric;

	uint8_t prefix_length;

	struct in_addr destination;
} __attribute__((packed));

struct TLV_IPv4_External_type {
	uint16_t type;
	uint16_t length;
	struct in_addr next_hop;
	struct in_addr originating_router;
	uint32_t originating_as;
	uint32_t administrative_tag;
	uint32_t external_metric;
	uint16_t reserved;
	uint8_t external_protocol;
	uint8_t external_flags;

	/*Metrics*/
	struct eigrp_metrics metric;

	uint8_t prefix_length;
	unsigned char destination_part[4];
	struct in_addr destination;
} __attribute__((packed));

/* EIGRP Peer Termination TLV - used for hard restart */
struct TLV_Peer_Termination_type {
	uint16_t type;
	uint16_t length;
	uint8_t unknown;
	uint32_t neighbor_ip;
} __attribute__((packed));

/* Who executed Graceful restart */
enum GR_type { EIGRP_GR_MANUAL, EIGRP_GR_FILTER };

//---------------------------------------------------------------------------------------------------------------------------------------------

/* EIGRP Topology table node structure */
typedef struct eigrp_prefix_descriptor {
	struct list *entries, *rij;
	struct prefix *destination;

	eigrp_metrics_t reported_metric; // RD for sending
	uint32_t fdistance;		 // FD
	uint32_t rdistance;		 // RD
	uint32_t distance;		 // D

	uint8_t nt;	    // network type
	uint8_t state;	    // route FSM state
	uint8_t req_action; // required action

	// If network type is REMOTE_EXTERNAL, pointer will have reference to
	// its external TLV
//	uint8_t af;	    // address family
	struct TLV_IPv4_External_type *extTLV;

	uint64_t serno; /*Serial number for this entry. Increased with each
			  change of entry*/
} eigrp_prefix_descriptor_t;

/* EIGRP Topology table record structure */
typedef struct eigrp_route_descriptor {
	uint16_t type;
	struct prefix dest;			// destination address
	eigrp_addr_t nexthop;			// address of advertised by peer

	eigrp_prefix_descriptor_t *prefix;	// prefix this route is part of
	eigrp_neighbor_t *adv_router;		// peer who sent me the route

	eigrp_metrics_t reported_metric;	// neighbors vector metrics
	uint32_t reported_distance;		// neighbors distance (RD)

	eigrp_metrics_t total_metric;		// calculated vector metrics
	uint32_t distance;		// calculatd distance (RD + link cost)

	eigrp_metrics_t metric;
	eigrp_extdata_t extdata;

	uint8_t flags; // used for marking successor and FS

	eigrp_interface_t *ei; // pointer for case of connected entry
} eigrp_route_descriptor_t;

//---------------------------------------------------------------------------------------------------------------------------------------------

#endif /* _ZEBRA_EIGRP_STRUCTURES_H_ */