src/libsystemd-network/lldp-neighbor.h

/* SPDX-License-Identifier: LGPL-2.1+ */
#pragma once

/***
  This file is part of systemd.

  Copyright 2016 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <inttypes.h>
#include <stdbool.h>
#include <sys/types.h>

#include "sd-lldp.h"

#include "hash-funcs.h"
#include "lldp-internal.h"
#include "time-util.h"

typedef struct LLDPNeighborID {
        /* The spec calls this an "MSAP identifier" */
        void *chassis_id;
        size_t chassis_id_size;

        void *port_id;
        size_t port_id_size;
} LLDPNeighborID;

struct sd_lldp_neighbor {
        /* Neighbor objects stay around as long as they are linked into an "sd_lldp" object or n_ref > 0. */
        sd_lldp *lldp;
        unsigned n_ref;

        triple_timestamp timestamp;

        usec_t until;
        unsigned prioq_idx;

        struct ether_addr source_address;
        struct ether_addr destination_address;

        LLDPNeighborID id;

        /* The raw packet size. The data is appended to the object, accessible via LLDP_NEIGHBOR_RAW() */
        size_t raw_size;

        /* The current read index for the iterative TLV interface */
        size_t rindex;

        /* And a couple of fields parsed out. */
        bool has_ttl:1;
        bool has_capabilities:1;
        bool has_port_vlan_id:1;

        uint16_t ttl;

        uint16_t system_capabilities;
        uint16_t enabled_capabilities;

        char *port_description;
        char *system_name;
        char *system_description;

        uint16_t port_vlan_id;

        char *chassis_id_as_string;
        char *port_id_as_string;
};

static inline void *LLDP_NEIGHBOR_RAW(const sd_lldp_neighbor *n) {
        return (uint8_t*) n + ALIGN(sizeof(sd_lldp_neighbor));
}

static inline uint8_t LLDP_NEIGHBOR_TLV_TYPE(const sd_lldp_neighbor *n) {
        return ((uint8_t*) LLDP_NEIGHBOR_RAW(n))[n->rindex] >> 1;
}

static inline size_t LLDP_NEIGHBOR_TLV_LENGTH(const sd_lldp_neighbor *n) {
        uint8_t *p;

        p = (uint8_t*) LLDP_NEIGHBOR_RAW(n) + n->rindex;
        return p[1] + (((size_t) (p[0] & 1)) << 8);
}

static inline void* LLDP_NEIGHBOR_TLV_DATA(const sd_lldp_neighbor *n) {
        return ((uint8_t*) LLDP_NEIGHBOR_RAW(n)) + n->rindex + 2;
}

extern const struct hash_ops lldp_neighbor_id_hash_ops;
int lldp_neighbor_prioq_compare_func(const void *a, const void *b);

sd_lldp_neighbor *lldp_neighbor_unlink(sd_lldp_neighbor *n);
sd_lldp_neighbor *lldp_neighbor_new(size_t raw_size);
int lldp_neighbor_parse(sd_lldp_neighbor *n);
void lldp_neighbor_start_ttl(sd_lldp_neighbor *n);
bool lldp_neighbor_equal(const sd_lldp_neighbor *a, const sd_lldp_neighbor *b);