networkd: Introduce Link Layer Discovery Protocol (LLDP)

This patch introduces LLDP support to networkd. it implements the
receiver side of the protocol.

The Link Layer Discovery Protocol (LLDP) is an industry-standard,
vendor-neutral method to allow networked devices to advertise
capabilities, identity, and other information onto a LAN. The Layer 2
protocol, detailed in IEEE 802.1AB-2005.LLDP allows network devices
that operate at the lower layers of a protocol stack (such as
Layer 2 bridges and switches) to learn some of the capabilities
and characteristics of LAN devices available to higher
layer protocols.

1 files changed, 93 insertions, 0 deletions

diff --git a/src/libsystemd-network/lldp-internal.h b/src/libsystemd-network/lldp-internal.h
new file mode 100644
index 0000000000..dbaf389792
--- /dev/null
+++ b/src/libsystemd-network/lldp-internal.h
@@ -0,0 +1,93 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright (C) 2014 Tom Gundersen
+  Copyright (C) 2014 Susant Sahani
+
+  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/>.
+***/
+
+#pragma once
+
+#include "log.h"
+#include "list.h"
+#include "refcnt.h"
+#include "lldp-tlv.h"
+#include "prioq.h"
+
+typedef struct lldp_neighbour_port lldp_neighbour_port;
+typedef struct lldp_chassis lldp_chassis;
+typedef struct lldp_chassis_id lldp_chassis_id;
+
+struct lldp_neighbour_port {
+        uint8_t type;
+        uint8_t *data;
+
+        uint16_t length;
+        usec_t until;
+
+        unsigned prioq_idx;
+
+        lldp_chassis *c;
+        tlv_packet *packet;
+
+        LIST_FIELDS(lldp_neighbour_port, port);
+};
+
+int lldp_neighbour_port_new(lldp_chassis *c, tlv_packet *tlv, lldp_neighbour_port **ret);
+void lldp_neighbour_port_free(lldp_neighbour_port *p);
+void lldp_neighbour_port_remove_and_free(lldp_neighbour_port *p);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(lldp_neighbour_port *, lldp_neighbour_port_free);
+#define _cleanup_lldp_neighbour_port_free_ _cleanup_(lldp_neighbour_port_freep)
+
+struct lldp_chassis_id {
+        uint8_t type;
+        uint16_t length;
+
+        uint8_t *data;
+};
+
+struct lldp_chassis {
+        RefCount n_ref;
+
+        lldp_chassis_id chassis_id;
+
+        Prioq *by_expiry;
+        Hashmap *neighbour_mib;
+
+        LIST_HEAD(lldp_neighbour_port, ports);
+};
+
+int lldp_chassis_new(tlv_packet *tlv,
+                     Prioq *by_expiry,
+                     Hashmap *neighbour_mib,
+                     lldp_chassis **ret);
+
+void lldp_chassis_free(lldp_chassis *c);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(lldp_chassis *, lldp_chassis_free);
+#define _cleanup_lldp_chassis_free_ _cleanup_(lldp_chassis_freep)
+
+int lldp_mib_update_objects(lldp_chassis *c, tlv_packet *tlv);
+int lldp_mib_add_objects(Prioq *by_expiry, Hashmap *neighbour_mib, tlv_packet *tlv);
+int lldp_mib_remove_objects(lldp_chassis *c, tlv_packet *tlv);
+
+int lldp_read_chassis_id(tlv_packet *tlv, uint8_t *type, uint16_t *length, uint8_t **data);
+int lldp_read_port_id(tlv_packet *tlv, uint8_t *type, uint16_t *length, uint8_t **data);
+int lldp_read_ttl(tlv_packet *tlv, uint16_t *ttl);
+
+#define log_lldp(fmt, ...) log_internal(LOG_DEBUG, 0, __FILE__, __LINE__, __func__, "LLDP: " fmt, ##__VA_ARGS__)