+++ /dev/null
-/***
- This file is part of elogind.
-
- Copyright 2016 Lennart Poettering
-
- elogind 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.
-
- elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <endian.h>
-#include <inttypes.h>
-#include <string.h>
-
-#include "fd-util.h"
-#include "fileio.h"
-#include "hostname-util.h"
-#include "lldp.h"
-#include "networkd-lldp-tx.h"
-#include "random-util.h"
-#include "socket-util.h"
-#include "string-util.h"
-#include "unaligned.h"
-
-/* The LLDP spec calls this "txFastInit", see 9.2.5.19 */
-#define LLDP_TX_FAST_INIT 4U
-
-/* The LLDP spec calls this "msgTxHold", see 9.2.5.6 */
-#define LLDP_TX_HOLD 4U
-
-/* The jitter range to add, see 9.2.2. */
-#define LLDP_JITTER_USEC (400U * USEC_PER_MSEC)
-
-/* The LLDP spec calls this msgTxInterval, but we subtract half the jitter off it. */
-#define LLDP_TX_INTERVAL_USEC (30U * USEC_PER_SEC - LLDP_JITTER_USEC / 2)
-
-/* The LLDP spec calls this msgFastTx, but we subtract half the jitter off it. */
-#define LLDP_FAST_TX_USEC (1U * USEC_PER_SEC - LLDP_JITTER_USEC / 2)
-
-static int lldp_write_tlv_header(uint8_t **p, uint8_t id, size_t sz) {
- assert(p);
-
- if (id > 127)
- return -EBADMSG;
- if (sz > 511)
- return -ENOBUFS;
-
- (*p)[0] = (id << 1) | !!(sz & 256);
- (*p)[1] = sz & 255;
-
- *p = *p + 2;
- return 0;
-}
-
-static int lldp_make_packet(
- const struct ether_addr *hwaddr,
- const char *machine_id,
- const char *ifname,
- uint16_t ttl,
- const char *port_description,
- const char *hostname,
- const char *pretty_hostname,
- uint16_t system_capabilities,
- uint16_t enabled_capabilities,
- void **ret, size_t *sz) {
-
- size_t machine_id_length, ifname_length, port_description_length = 0, hostname_length = 0, pretty_hostname_length = 0;
- _cleanup_free_ void *packet = NULL;
- struct ether_header *h;
- uint8_t *p;
- size_t l;
- int r;
-
- assert(hwaddr);
- assert(machine_id);
- assert(ifname);
- assert(ret);
- assert(sz);
-
- machine_id_length = strlen(machine_id);
- ifname_length = strlen(ifname);
-
- if (port_description)
- port_description_length = strlen(port_description);
-
- if (hostname)
- hostname_length = strlen(hostname);
-
- if (pretty_hostname)
- pretty_hostname_length = strlen(pretty_hostname);
-
- l = sizeof(struct ether_header) +
- /* Chassis ID */
- 2 + 1 + machine_id_length +
- /* Port ID */
- 2 + 1 + ifname_length +
- /* TTL */
- 2 + 2 +
- /* System Capabilities */
- 2 + 4 +
- /* End */
- 2;
-
- /* Port Description */
- if (port_description)
- l += 2 + port_description_length;
-
- /* System Name */
- if (hostname)
- l += 2 + hostname_length;
-
- /* System Description */
- if (pretty_hostname)
- l += 2 + pretty_hostname_length;
-
- packet = malloc(l);
- if (!packet)
- return -ENOMEM;
-
- h = (struct ether_header*) packet;
- h->ether_type = htobe16(ETHERTYPE_LLDP);
- memcpy(h->ether_dhost, &(struct ether_addr) { LLDP_MULTICAST_ADDR }, ETH_ALEN);
- memcpy(h->ether_shost, hwaddr, ETH_ALEN);
-
- p = (uint8_t*) packet + sizeof(struct ether_header);
-
- r = lldp_write_tlv_header(&p, LLDP_TYPE_CHASSIS_ID, 1 + machine_id_length);
- if (r < 0)
- return r;
- *(p++) = LLDP_CHASSIS_SUBTYPE_LOCALLY_ASSIGNED;
- p = mempcpy(p, machine_id, machine_id_length);
-
- r = lldp_write_tlv_header(&p, LLDP_TYPE_PORT_ID, 1 + ifname_length);
- if (r < 0)
- return r;
- *(p++) = LLDP_PORT_SUBTYPE_INTERFACE_NAME;
- p = mempcpy(p, ifname, ifname_length);
-
- r = lldp_write_tlv_header(&p, LLDP_TYPE_TTL, 2);
- if (r < 0)
- return r;
- unaligned_write_be16(p, ttl);
- p += 2;
-
- if (port_description) {
- r = lldp_write_tlv_header(&p, LLDP_TYPE_PORT_DESCRIPTION, port_description_length);
- if (r < 0)
- return r;
- p = mempcpy(p, port_description, port_description_length);
- }
-
- if (hostname) {
- r = lldp_write_tlv_header(&p, LLDP_TYPE_SYSTEM_NAME, hostname_length);
- if (r < 0)
- return r;
- p = mempcpy(p, hostname, hostname_length);
- }
-
- if (pretty_hostname) {
- r = lldp_write_tlv_header(&p, LLDP_TYPE_SYSTEM_DESCRIPTION, pretty_hostname_length);
- if (r < 0)
- return r;
- p = mempcpy(p, pretty_hostname, pretty_hostname_length);
- }
-
- r = lldp_write_tlv_header(&p, LLDP_TYPE_SYSTEM_CAPABILITIES, 4);
- if (r < 0)
- return r;
- unaligned_write_be16(p, system_capabilities);
- p += 2;
- unaligned_write_be16(p, enabled_capabilities);
- p += 2;
-
- r = lldp_write_tlv_header(&p, LLDP_TYPE_END, 0);
- if (r < 0)
- return r;
-
- assert(p == (uint8_t*) packet + l);
-
- *ret = packet;
- *sz = l;
-
- packet = NULL;
- return 0;
-}
-
-static int lldp_send_packet(int ifindex, const void *packet, size_t packet_size) {
-
- union sockaddr_union sa = {
- .ll.sll_family = AF_PACKET,
- .ll.sll_protocol = htobe16(ETHERTYPE_LLDP),
- .ll.sll_ifindex = ifindex,
- .ll.sll_halen = ETH_ALEN,
- .ll.sll_addr = LLDP_MULTICAST_ADDR,
- };
-
- _cleanup_close_ int fd = -1;
- ssize_t l;
-
- assert(ifindex > 0);
- assert(packet || packet_size <= 0);
-
- fd = socket(PF_PACKET, SOCK_RAW|SOCK_CLOEXEC, IPPROTO_RAW);
- if (fd < 0)
- return -errno;
-
- l = sendto(fd, packet, packet_size, MSG_NOSIGNAL, &sa.sa, sizeof(sa.ll));
- if (l < 0)
- return -errno;
-
- if ((size_t) l != packet_size)
- return -EIO;
-
- return 0;
-}
-
-static int link_send_lldp(Link *link) {
- char machine_id_string[SD_ID128_STRING_MAX];
- _cleanup_free_ char *hostname = NULL, *pretty_hostname = NULL;
- _cleanup_free_ void *packet = NULL;
- size_t packet_size = 0;
- sd_id128_t machine_id;
- uint16_t caps;
- usec_t ttl;
- int r;
-
- r = sd_id128_get_machine(&machine_id);
- if (r < 0)
- return r;
-
- (void) gethostname_strict(&hostname);
- (void) parse_env_file("/etc/machine-info", NEWLINE, "PRETTY_HOSTNAME", &pretty_hostname, NULL);
-
- ttl = DIV_ROUND_UP(LLDP_TX_INTERVAL_USEC * LLDP_TX_HOLD + 1, USEC_PER_SEC);
- if (ttl > (usec_t) UINT16_MAX)
- ttl = (usec_t) UINT16_MAX;
-
- caps = (link->network && link->network->ip_forward != ADDRESS_FAMILY_NO) ?
- LLDP_SYSTEM_CAPABILITIES_ROUTER :
- LLDP_SYSTEM_CAPABILITIES_STATION;
-
- r = lldp_make_packet(&link->mac,
- sd_id128_to_string(machine_id, machine_id_string),
- link->ifname,
- (uint16_t) ttl,
- link->network ? link->network->description : NULL,
- hostname,
- pretty_hostname,
- LLDP_SYSTEM_CAPABILITIES_STATION|LLDP_SYSTEM_CAPABILITIES_BRIDGE|LLDP_SYSTEM_CAPABILITIES_ROUTER,
- caps,
- &packet, &packet_size);
- if (r < 0)
- return r;
-
- return lldp_send_packet(link->ifindex, packet, packet_size);
-}
-
-static int on_lldp_timer(sd_event_source *s, usec_t t, void *userdata) {
- Link *link = userdata;
- usec_t current, delay, next;
- int r;
-
- assert(s);
- assert(userdata);
-
- log_link_debug(link, "Sending LLDP packet...");
-
- r = link_send_lldp(link);
- if (r < 0)
- log_link_debug_errno(link, r, "Failed to send LLDP packet, ignoring: %m");
-
- if (link->lldp_tx_fast > 0)
- link->lldp_tx_fast--;
-
- assert_se(sd_event_now(sd_event_source_get_event(s), clock_boottime_or_monotonic(), ¤t) >= 0);
-
- delay = link->lldp_tx_fast > 0 ? LLDP_FAST_TX_USEC : LLDP_TX_INTERVAL_USEC;
- next = usec_add(usec_add(current, delay), (usec_t) random_u64() % LLDP_JITTER_USEC);
-
- r = sd_event_source_set_time(s, next);
- if (r < 0)
- return log_link_error_errno(link, r, "Failed to restart LLDP timer: %m");
-
- r = sd_event_source_set_enabled(s, SD_EVENT_ONESHOT);
- if (r < 0)
- return log_link_error_errno(link, r, "Failed to enable LLDP timer: %m");
-
- return 0;
-}
-
-int link_lldp_tx_start(Link *link) {
- usec_t next;
- int r;
-
- assert(link);
-
- /* Starts the LLDP transmission in "fast" mode. If it is already started, turns "fast" mode back on again. */
-
- link->lldp_tx_fast = LLDP_TX_FAST_INIT;
-
- next = usec_add(usec_add(now(clock_boottime_or_monotonic()), LLDP_FAST_TX_USEC),
- (usec_t) random_u64() % LLDP_JITTER_USEC);
-
- if (link->lldp_tx_event_source) {
- usec_t old;
-
- /* Lower the timeout, maybe */
- r = sd_event_source_get_time(link->lldp_tx_event_source, &old);
- if (r < 0)
- return r;
-
- if (old <= next)
- return 0;
-
- return sd_event_source_set_time(link->lldp_tx_event_source, next);
- } else {
- r = sd_event_add_time(
- link->manager->event,
- &link->lldp_tx_event_source,
- clock_boottime_or_monotonic(),
- next,
- 0,
- on_lldp_timer,
- link);
- if (r < 0)
- return r;
-
- (void) sd_event_source_set_description(link->lldp_tx_event_source, "lldp-tx");
- }
-
- return 0;
-}
-
-void link_lldp_tx_stop(Link *link) {
- assert(link);
-
- link->lldp_tx_event_source = sd_event_source_unref(link->lldp_tx_event_source);
-}
~ianmdlvl / elogind.git / commitdiff