diff options
Diffstat (limited to '')
| -rw-r--r-- | src/network/networkd-lldp-rx.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/src/network/networkd-lldp-rx.c b/src/network/networkd-lldp-rx.c new file mode 100644 index 0000000..c22852f --- /dev/null +++ b/src/network/networkd-lldp-rx.c @@ -0,0 +1,205 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <net/if.h> +#include <net/if_arp.h> +#include <unistd.h> + +#include "fd-util.h" +#include "fileio.h" +#include "networkd-link.h" +#include "networkd-lldp-rx.h" +#include "networkd-lldp-tx.h" +#include "networkd-manager.h" +#include "networkd-network.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" +#include "tmpfile-util.h" + +DEFINE_CONFIG_PARSE_ENUM(config_parse_lldp_mode, lldp_mode, LLDPMode, "Failed to parse LLDP= setting."); + +static const char* const lldp_mode_table[_LLDP_MODE_MAX] = { + [LLDP_MODE_NO] = "no", + [LLDP_MODE_YES] = "yes", + [LLDP_MODE_ROUTERS_ONLY] = "routers-only", +}; + +DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(lldp_mode, LLDPMode, LLDP_MODE_YES); + +static bool link_lldp_rx_enabled(Link *link) { + assert(link); + + if (link->flags & IFF_LOOPBACK) + return false; + + if (link->iftype != ARPHRD_ETHER) + return false; + + if (!link->network) + return false; + + /* LLDP should be handled on bridge and bond slaves as those have a direct connection to their peers, + * not on the bridge/bond master. Linux doesn't even (by default) forward lldp packets to the bridge + * master.*/ + if (link->kind && STR_IN_SET(link->kind, "bridge", "bond")) + return false; + + return link->network->lldp_mode != LLDP_MODE_NO; +} + +static void lldp_handler(sd_lldp *lldp, sd_lldp_event event, sd_lldp_neighbor *n, void *userdata) { + Link *link = userdata; + int r; + + assert(link); + + (void) link_lldp_save(link); + + if (link_lldp_emit_enabled(link) && event == SD_LLDP_EVENT_ADDED) { + /* If we received information about a new neighbor, restart the LLDP "fast" logic */ + + log_link_debug(link, "Received LLDP datagram from previously unknown neighbor, restarting 'fast' LLDP transmission."); + + r = link_lldp_emit_start(link); + if (r < 0) + log_link_warning_errno(link, r, "Failed to restart LLDP transmission: %m"); + } +} + +int link_lldp_rx_configure(Link *link) { + int r; + + if (!link_lldp_rx_enabled(link)) + return 0; + + if (!link->lldp) { + r = sd_lldp_new(&link->lldp); + if (r < 0) + return r; + + r = sd_lldp_attach_event(link->lldp, link->manager->event, 0); + if (r < 0) + return r; + } + + r = sd_lldp_set_ifindex(link->lldp, link->ifindex); + if (r < 0) + return r; + + r = sd_lldp_match_capabilities(link->lldp, + link->network->lldp_mode == LLDP_MODE_ROUTERS_ONLY ? + SD_LLDP_SYSTEM_CAPABILITIES_ALL_ROUTERS : + SD_LLDP_SYSTEM_CAPABILITIES_ALL); + if (r < 0) + return r; + + r = sd_lldp_set_filter_address(link->lldp, &link->hw_addr.addr.ether); + if (r < 0) + return r; + + r = sd_lldp_set_callback(link->lldp, lldp_handler, link); + if (r < 0) + return r; + + r = link_update_lldp(link); + if (r < 0) + return r; + + return 0; +} + +int link_update_lldp(Link *link) { + int r; + + assert(link); + + if (!link->lldp) + return 0; + + if (link->flags & IFF_UP) { + r = sd_lldp_start(link->lldp); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to start LLDP: %m"); + if (r > 0) + log_link_debug(link, "Started LLDP."); + } else { + r = sd_lldp_stop(link->lldp); + if (r < 0) + return log_link_warning_errno(link, r, "Failed to stop LLDP: %m"); + if (r > 0) + log_link_debug(link, "Stopped LLDP."); + } + + return r; +} + +int link_lldp_save(Link *link) { + _cleanup_free_ char *temp_path = NULL; + _cleanup_fclose_ FILE *f = NULL; + sd_lldp_neighbor **l = NULL; + int n = 0, r, i; + + assert(link); + assert(link->lldp_file); + + if (!link->lldp) { + (void) unlink(link->lldp_file); + return 0; + } + + r = sd_lldp_get_neighbors(link->lldp, &l); + if (r < 0) + goto finish; + if (r == 0) { + (void) unlink(link->lldp_file); + goto finish; + } + + n = r; + + r = fopen_temporary(link->lldp_file, &f, &temp_path); + if (r < 0) + goto finish; + + fchmod(fileno(f), 0644); + + for (i = 0; i < n; i++) { + const void *p; + le64_t u; + size_t sz; + + r = sd_lldp_neighbor_get_raw(l[i], &p, &sz); + if (r < 0) + goto finish; + + u = htole64(sz); + (void) fwrite(&u, 1, sizeof(u), f); + (void) fwrite(p, 1, sz, f); + } + + r = fflush_and_check(f); + if (r < 0) + goto finish; + + if (rename(temp_path, link->lldp_file) < 0) { + r = -errno; + goto finish; + } + +finish: + if (r < 0) { + (void) unlink(link->lldp_file); + if (temp_path) + (void) unlink(temp_path); + + log_link_error_errno(link, r, "Failed to save LLDP data to %s: %m", link->lldp_file); + } + + if (l) { + for (i = 0; i < n; i++) + sd_lldp_neighbor_unref(l[i]); + free(l); + } + + return r; +} |