blob: f2d4e6f2bbb15a20ddcf5afe01a1bba5c9035df7 [file] [log] [blame] [raw]
/* SPDX-License-Identifier: LGPL-2.1+ */
#include <endian.h>
#include <inttypes.h>
#include <net/if.h>
#include <net/if_arp.h>
#include "alloc-util.h"
#include "env-file.h"
#include "escape.h"
#include "fd-util.h"
#include "hostname-util.h"
#include "missing_network.h"
#include "networkd-link.h"
#include "networkd-lldp-tx.h"
#include "networkd-manager.h"
#include "parse-util.h"
#include "random-util.h"
#include "socket-util.h"
#include "string-util.h"
#include "strv.h"
#include "unaligned.h"
#include "web-util.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 const struct ether_addr lldp_multicast_addr[_LLDP_EMIT_MAX] = {
[LLDP_EMIT_NEAREST_BRIDGE] = {{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x0e }},
[LLDP_EMIT_NON_TPMR_BRIDGE] = {{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x03 }},
[LLDP_EMIT_CUSTOMER_BRIDGE] = {{ 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }},
};
bool link_lldp_emit_enabled(Link *link) {
assert(link);
if (link->flags & IFF_LOOPBACK)
return false;
if (link->iftype != ARPHRD_ETHER)
return false;
if (!link->network)
return false;
if (link->kind && STR_IN_SET(link->kind, "bridge", "bond"))
return false;
return link->network->lldp_emit != LLDP_EMIT_NO;
}
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(
LLDPEmit mode,
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,
char *mud,
void **ret, size_t *sz) {
size_t machine_id_length, ifname_length, port_description_length = 0, hostname_length = 0,
pretty_hostname_length = 0, mud_length = 0;
_cleanup_free_ void *packet = NULL;
struct ether_header *h;
uint8_t *p;
size_t l;
int r;
assert(mode > LLDP_EMIT_NO);
assert(mode < _LLDP_EMIT_MAX);
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);
if (mud)
mud_length = strlen(mud);
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;
/* MUD URL */
if (mud)
l += 2 + sizeof(SD_LLDP_OUI_MUD) + 1 + mud_length;
packet = malloc(l);
if (!packet)
return -ENOMEM;
h = (struct ether_header*) packet;
h->ether_type = htobe16(ETHERTYPE_LLDP);
memcpy(h->ether_dhost, lldp_multicast_addr + mode, ETH_ALEN);
memcpy(h->ether_shost, hwaddr, ETH_ALEN);
p = (uint8_t*) packet + sizeof(struct ether_header);
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_CHASSIS_ID, 1 + machine_id_length);
if (r < 0)
return r;
*(p++) = SD_LLDP_CHASSIS_SUBTYPE_LOCALLY_ASSIGNED;
p = mempcpy(p, machine_id, machine_id_length);
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_PORT_ID, 1 + ifname_length);
if (r < 0)
return r;
*(p++) = SD_LLDP_PORT_SUBTYPE_INTERFACE_NAME;
p = mempcpy(p, ifname, ifname_length);
r = lldp_write_tlv_header(&p, SD_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, SD_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, SD_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, SD_LLDP_TYPE_SYSTEM_DESCRIPTION, pretty_hostname_length);
if (r < 0)
return r;
p = mempcpy(p, pretty_hostname, pretty_hostname_length);
}
if (mud) {
uint8_t oui_mud[sizeof(SD_LLDP_OUI_MUD)] = {0x00, 0x00, 0x5E};
/*
* +--------+--------+----------+---------+--------------
* |TLV Type| len | OUI |subtype | MUDString
* | =127 | |= 00 00 5E| = 1 |
* |(7 bits)|(9 bits)|(3 octets)|(1 octet)|(1-255 octets)
* +--------+--------+----------+---------+--------------
* where:
* o TLV Type = 127 indicates a vendor-specific TLV
* o len = indicates the TLV string length
* o OUI = 00 00 5E is the organizationally unique identifier of IANA
* o subtype = 1 (as assigned by IANA for the MUDstring)
* o MUDstring = the length MUST NOT exceed 255 octets
*/
r = lldp_write_tlv_header(&p, SD_LLDP_TYPE_PRIVATE, sizeof(SD_LLDP_OUI_MUD) + 1 + mud_length);
if (r < 0)
return r;
p = mempcpy(p, &oui_mud, sizeof(SD_LLDP_OUI_MUD));
*(p++) = SD_LLDP_OUI_SUBTYPE_MUD_USAGE_DESCRIPTION;
p = mempcpy(p, mud, mud_length);
}
r = lldp_write_tlv_header(&p, SD_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, SD_LLDP_TYPE_END, 0);
if (r < 0)
return r;
assert(p == (uint8_t*) packet + l);
*ret = TAKE_PTR(packet);
*sz = l;
return 0;
}
static int lldp_send_packet(
int ifindex,
const struct ether_addr *address,
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,
};
_cleanup_close_ int fd = -1;
ssize_t l;
assert(ifindex > 0);
assert(address);
assert(packet || packet_size <= 0);
memcpy(sa.ll.sll_addr, address, ETH_ALEN);
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;
assert(link);
if (!link->network || link->network->lldp_emit == LLDP_EMIT_NO)
return 0;
assert(link->network->lldp_emit < _LLDP_EMIT_MAX);
r = sd_id128_get_machine(&machine_id);
if (r < 0)
return r;
(void) gethostname_strict(&hostname);
(void) parse_env_file(NULL, "/etc/machine-info", "PRETTY_HOSTNAME", &pretty_hostname);
assert_cc(LLDP_TX_INTERVAL_USEC * LLDP_TX_HOLD + 1 <= (UINT16_MAX - 1) * USEC_PER_SEC);
ttl = DIV_ROUND_UP(LLDP_TX_INTERVAL_USEC * LLDP_TX_HOLD + 1, USEC_PER_SEC);
caps = (link->network && link->network->ip_forward != ADDRESS_FAMILY_NO) ?
SD_LLDP_SYSTEM_CAPABILITIES_ROUTER :
SD_LLDP_SYSTEM_CAPABILITIES_STATION;
r = lldp_make_packet(link->network->lldp_emit,
&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,
SD_LLDP_SYSTEM_CAPABILITIES_STATION|SD_LLDP_SYSTEM_CAPABILITIES_BRIDGE|SD_LLDP_SYSTEM_CAPABILITIES_ROUTER,
caps,
link->network ? link->network->lldp_mud : NULL,
&packet, &packet_size);
if (r < 0)
return r;
return lldp_send_packet(link->ifindex, lldp_multicast_addr + link->network->lldp_emit, 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(), &current) >= 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_emit_start(Link *link) {
usec_t next;
int r;
assert(link);
if (!link->network || link->network->lldp_emit == LLDP_EMIT_NO) {
link_lldp_emit_stop(link);
return 0;
}
/* 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_emit_event_source) {
usec_t old;
/* Lower the timeout, maybe */
r = sd_event_source_get_time(link->lldp_emit_event_source, &old);
if (r < 0)
return r;
if (old <= next)
return 0;
return sd_event_source_set_time(link->lldp_emit_event_source, next);
} else {
r = sd_event_add_time(
link->manager->event,
&link->lldp_emit_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_emit_event_source, "lldp-tx");
}
return 0;
}
void link_lldp_emit_stop(Link *link) {
assert(link);
link->lldp_emit_event_source = sd_event_source_unref(link->lldp_emit_event_source);
}
int config_parse_lldp_emit(
const char *unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
LLDPEmit *emit = data;
int r;
assert(filename);
assert(lvalue);
assert(rvalue);
if (isempty(rvalue))
*emit = LLDP_EMIT_NO;
else if (streq(rvalue, "nearest-bridge"))
*emit = LLDP_EMIT_NEAREST_BRIDGE;
else if (streq(rvalue, "non-tpmr-bridge"))
*emit = LLDP_EMIT_NON_TPMR_BRIDGE;
else if (streq(rvalue, "customer-bridge"))
*emit = LLDP_EMIT_CUSTOMER_BRIDGE;
else {
r = parse_boolean(rvalue);
if (r < 0) {
log_syntax(unit, LOG_ERR, filename, line, 0, "Failed to parse LLDP emission setting, ignoring: %s", rvalue);
return 0;
}
*emit = r ? LLDP_EMIT_NEAREST_BRIDGE : LLDP_EMIT_NO;
}
return 0;
}
int config_parse_lldp_mud(
const char *unit,
const char *filename,
unsigned line,
const char *section,
unsigned section_line,
const char *lvalue,
int ltype,
const char *rvalue,
void *data,
void *userdata) {
_cleanup_free_ char *unescaped = NULL;
Network *n = data;
int r;
assert(filename);
assert(lvalue);
assert(rvalue);
r = cunescape(rvalue, 0, &unescaped);
if (r < 0) {
log_syntax(unit, LOG_ERR, filename, line, r,
"Failed to Failed to unescape LLDP MUD URL, ignoring: %s", rvalue);
return 0;
}
if (!http_url_is_valid(unescaped) || strlen(unescaped) > 255) {
log_syntax(unit, LOG_ERR, filename, line, 0,
"Failed to parse LLDP MUD URL '%s', ignoring: %m", rvalue);
return 0;
}
return free_and_replace(n->lldp_mud, unescaped);
}