diff options
-rw-r--r-- | Makefile.am | 4 | ||||
-rw-r--r-- | src/basic/hostname-util.c | 28 | ||||
-rw-r--r-- | src/basic/hostname-util.h | 1 | ||||
-rw-r--r-- | src/network/networkd-link.c | 29 | ||||
-rw-r--r-- | src/network/networkd-link.h | 5 | ||||
-rw-r--r-- | src/network/networkd-lldp-tx.c | 347 | ||||
-rw-r--r-- | src/network/networkd-lldp-tx.h | 25 | ||||
-rw-r--r-- | src/network/networkd-network-gperf.gperf | 1 | ||||
-rw-r--r-- | src/network/networkd-network.h | 3 |
9 files changed, 439 insertions, 4 deletions
diff --git a/Makefile.am b/Makefile.am index 70fcedf0da..627a076cd9 100644 --- a/Makefile.am +++ b/Makefile.am @@ -5341,7 +5341,9 @@ libnetworkd_core_la_SOURCES = \ src/network/networkd-address-pool.h \ src/network/networkd-address-pool.c \ src/network/networkd-util.h \ - src/network/networkd-util.c + src/network/networkd-util.c \ + src/network/networkd-lldp-tx.h \ + src/network/networkd-lldp-tx.c nodist_libnetworkd_core_la_SOURCES = \ src/network/networkd-network-gperf.c \ diff --git a/src/basic/hostname-util.c b/src/basic/hostname-util.c index 57031b645c..f900c509a3 100644 --- a/src/basic/hostname-util.c +++ b/src/basic/hostname-util.c @@ -48,6 +48,9 @@ bool hostname_is_set(void) { char* gethostname_malloc(void) { struct utsname u; + /* This call tries to return something useful, either the actual hostname or it makes something up. The only + * reason it might mail is OOM. It might even return "localhost" if that's set. */ + assert_se(uname(&u) >= 0); if (isempty(u.nodename) || streq(u.nodename, "(none)")) @@ -56,6 +59,31 @@ char* gethostname_malloc(void) { return strdup(u.nodename); } +int gethostname_strict(char **ret) { + struct utsname u; + char *k; + + /* This call will rather fail than make up a name. It will not return "localhost" either. */ + + assert_se(uname(&u) >= 0); + + if (isempty(u.nodename)) + return -ENXIO; + + if (streq(u.nodename, "(none)")) + return -ENXIO; + + if (is_localhost(u.nodename)) + return -ENXIO; + + k = strdup(u.nodename); + if (!k) + return -ENOMEM; + + *ret = k; + return 0; +} + static bool hostname_valid_char(char c) { return (c >= 'a' && c <= 'z') || diff --git a/src/basic/hostname-util.h b/src/basic/hostname-util.h index d062eddea1..7af4e6c7ec 100644 --- a/src/basic/hostname-util.h +++ b/src/basic/hostname-util.h @@ -26,6 +26,7 @@ bool hostname_is_set(void); char* gethostname_malloc(void); +int gethostname_strict(char **ret); bool hostname_is_valid(const char *s, bool allow_trailing_dot) _pure_; char* hostname_cleanup(char *s); diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c index 2bc6e3c842..86fa4f07f2 100644 --- a/src/network/networkd-link.c +++ b/src/network/networkd-link.c @@ -30,6 +30,7 @@ #include "netlink-util.h" #include "network-internal.h" #include "networkd-link.h" +#include "networkd-lldp-tx.h" #include "networkd-netdev.h" #include "set.h" #include "socket-util.h" @@ -99,7 +100,7 @@ static bool link_ipv6ll_enabled(Link *link) { return link->network->link_local & ADDRESS_FAMILY_IPV6; } -static bool link_lldp_enabled(Link *link) { +static bool link_lldp_rx_enabled(Link *link) { assert(link); if (link->flags & IFF_LOOPBACK) @@ -117,6 +118,21 @@ static bool link_lldp_enabled(Link *link) { return link->network->lldp_mode != LLDP_MODE_NO; } +static bool link_lldp_tx_enabled(Link *link) { + assert(link); + + if (link->flags & IFF_LOOPBACK) + return false; + + if (link->iftype != ARPHRD_ETHER) + return false; + + if (!link->network) + return false; + + return link->network->lldp_emit; +} + static bool link_ipv4_forward_enabled(Link *link) { assert(link); @@ -419,6 +435,8 @@ static void link_free(Link *link) { sd_dhcp_client_unref(link->dhcp_client); sd_dhcp_lease_unref(link->dhcp_lease); + link_lldp_tx_stop(link); + free(link->lease_file); sd_lldp_unref(link->lldp); @@ -546,6 +564,7 @@ static int link_stop_clients(Link *link) { r = log_link_warning_errno(link, k, "Could not stop IPv6 Router Discovery: %m"); } + link_lldp_tx_stop(link); return r; } @@ -1383,6 +1402,12 @@ static int link_acquire_conf(Link *link) { return log_link_warning_errno(link, r, "Could not acquire DHCPv4 lease: %m"); } + if (link_lldp_tx_enabled(link)) { + r = link_lldp_tx_start(link); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to start LLDP transmission: %m"); + } + return 0; } @@ -2191,7 +2216,7 @@ static int link_configure(Link *link) { return r; } - if (link_lldp_enabled(link)) { + if (link_lldp_rx_enabled(link)) { r = sd_lldp_new(&link->lldp, link->ifindex); if (r < 0) return r; diff --git a/src/network/networkd-link.h b/src/network/networkd-link.h index d9f637cb6e..f2a64ca9b5 100644 --- a/src/network/networkd-link.h +++ b/src/network/networkd-link.h @@ -112,9 +112,14 @@ struct Link { sd_dhcp6_client *dhcp6_client; bool rtnl_extended_attrs; + /* This is about LLDP reception */ sd_lldp *lldp; char *lldp_file; + /* This is about LLDP transmission */ + unsigned lldp_tx_fast; /* The LLDP txFast counter (See 802.1ab-2009, section 9.2.5.18) */ + sd_event_source *lldp_tx_event_source; + Hashmap *bound_by_links; Hashmap *bound_to_links; }; diff --git a/src/network/networkd-lldp-tx.c b/src/network/networkd-lldp-tx.c new file mode 100644 index 0000000000..ae8367a60e --- /dev/null +++ b/src/network/networkd-lldp-tx.c @@ -0,0 +1,347 @@ +/*** + 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 <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); +} diff --git a/src/network/networkd-lldp-tx.h b/src/network/networkd-lldp-tx.h new file mode 100644 index 0000000000..8c7f403005 --- /dev/null +++ b/src/network/networkd-lldp-tx.h @@ -0,0 +1,25 @@ +#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 "networkd-link.h" + +int link_lldp_tx_start(Link *link); +void link_lldp_tx_stop(Link *link); diff --git a/src/network/networkd-network-gperf.gperf b/src/network/networkd-network-gperf.gperf index d67da5d7b6..a5d1714293 100644 --- a/src/network/networkd-network-gperf.gperf +++ b/src/network/networkd-network-gperf.gperf @@ -41,6 +41,7 @@ Network.LinkLocalAddressing, config_parse_address_family_boolean, Network.IPv4LLRoute, config_parse_bool, 0, offsetof(Network, ipv4ll_route) Network.IPv6Token, config_parse_ipv6token, 0, offsetof(Network, ipv6_token) Network.LLDP, config_parse_lldp_mode, 0, offsetof(Network, lldp_mode) +Network.EmitLLDP, config_parse_bool, 0, offsetof(Network, lldp_emit) Network.Address, config_parse_address, 0, 0 Network.Gateway, config_parse_gateway, 0, 0 Network.Domains, config_parse_domains, 0, 0 diff --git a/src/network/networkd-network.h b/src/network/networkd-network.h index 9dcebfbf7b..4a13e2b574 100644 --- a/src/network/networkd-network.h +++ b/src/network/networkd-network.h @@ -145,7 +145,8 @@ struct Network { struct ether_addr *mac; unsigned mtu; - LLDPMode lldp_mode; + LLDPMode lldp_mode; /* LLDP reception */ + bool lldp_emit; /* LLDP transmission */ LIST_HEAD(Address, static_addresses); LIST_HEAD(Route, static_routes); |