From 9ae68659b0870f3213a8e06011b1dbccdeb86ee6 Mon Sep 17 00:00:00 2001

From: Ryan Wilson <ryantimwilson@meta4.com>

Date: Wed, 4 Dec 2024 16:15:30 -0800

Subject: [PATCH] networkctl: Make lldp/status backwards compatible with 255

 over dbus

---

 src/libsystemd-network/lldp-neighbor.c |  22 +++

 src/network/networkctl-lldp.c          | 198 ++++++++++++++++++++++++-

 src/network/networkctl-lldp.h          |   1 +

 src/network/networkctl-status-link.c   |   9 +-

 src/network/networkctl-util.c          |   2 +-

 src/systemd/sd-lldp-rx.h               |   1 +

 6 files changed, 226 insertions(+), 7 deletions(-)

diff --git a/src/libsystemd-network/lldp-neighbor.c b/src/libsystemd-network/lldp-neighbor.c

index 457b1e5926..4e51a55bd1 100644

--- a/src/libsystemd-network/lldp-neighbor.c

+++ b/src/libsystemd-network/lldp-neighbor.c

@@ -630,6 +630,28 @@ int sd_lldp_neighbor_get_enabled_capabilities(sd_lldp_neighbor *n, uint16_t *ret

         return 0;

 }

+int sd_lldp_neighbor_from_raw(sd_lldp_neighbor **ret, const void *raw, size_t raw_size) {

+        _cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL;

+        int r;

+

+        assert_return(ret, -EINVAL);

+        assert_return(raw || raw_size <= 0, -EINVAL);

+

+        n = lldp_neighbor_new(raw_size);

+        if (!n)

+                return -ENOMEM;

+

+        memcpy_safe(LLDP_NEIGHBOR_RAW(n), raw, raw_size);

+

+        r = lldp_neighbor_parse(n);

+        if (r < 0)

+                return r;

+

+        *ret = TAKE_PTR(n);

+

+        return r;

+}

+

 int sd_lldp_neighbor_tlv_rewind(sd_lldp_neighbor *n) {

         assert_return(n, -EINVAL);

diff --git a/src/network/networkctl-lldp.c b/src/network/networkctl-lldp.c

index b1dc927af9..6a3a88210c 100644

--- a/src/network/networkctl-lldp.c

+++ b/src/network/networkctl-lldp.c

@@ -1,11 +1,15 @@

 /* SPDX-License-Identifier: LGPL-2.1-or-later */

 #include "alloc-util.h"

+#include "fd-util.h"

 #include "json-util.h"

 #include "networkctl.h"

 #include "networkctl-dump-util.h"

+#include "networkctl-link-info.h"

 #include "networkctl-lldp.h"

 #include "networkctl-util.h"

+#include "sd-lldp-rx.h"

+#include "sparse-endian.h"

 #include "stdio-util.h"

 #include "strv.h"

 #include "terminal-util.h"

@@ -214,6 +218,194 @@ static int dump_lldp_neighbors_json(sd_json_variant *reply, char * const *patter

         return sd_json_variant_dump(v, arg_json_format_flags, NULL, NULL);

 }

+static int open_lldp_neighbors_legacy(int ifindex, FILE **ret) {

+        _cleanup_fclose_ FILE *f = NULL;

+        char p[STRLEN("/run/systemd/netif/lldp/") + DECIMAL_STR_MAX(int)];

+

+        assert(ifindex >= 0);

+        assert(ret);

+

+        xsprintf(p, "/run/systemd/netif/lldp/%i", ifindex);

+

+        f = fopen(p, "re");

+        if (!f)

+                return -errno;

+

+        *ret = TAKE_PTR(f);

+        return 0;

+}

+

+static int next_lldp_neighbor_legacy(FILE *f, sd_lldp_neighbor **ret) {

+        _cleanup_free_ void *raw = NULL;

+        size_t l;

+        le64_t u;

+        int r;

+

+        assert(f);

+        assert(ret);

+

+        l = fread(&u, 1, sizeof(u), f);

+        if (l == 0 && feof(f))

+                return 0;

+        if (l != sizeof(u))

+                return -EBADMSG;

+

+        /* each LLDP packet is at most MTU size, but let's allow up to 4KiB just in case */

+        if (le64toh(u) >= 4096)

+                return -EBADMSG;

+

+        raw = new(uint8_t, le64toh(u));

+        if (!raw)

+                return -ENOMEM;

+

+        if (fread(raw, 1, le64toh(u), f) != le64toh(u))

+                return -EBADMSG;

+

+        r = sd_lldp_neighbor_from_raw(ret, raw, le64toh(u));

+        if (r < 0)

+                return r;

+

+        return 1;

+}

+

+int dump_lldp_neighbors_legacy(Table *table, const char *prefix, int ifindex) {

+        _cleanup_strv_free_ char **buf = NULL;

+        _cleanup_fclose_ FILE *f = NULL;

+        int r;

+

+        assert(table);

+        assert(prefix);

+        assert(ifindex > 0);

+

+        r = open_lldp_neighbors_legacy(ifindex, &f);

+        if (r == -ENOENT)

+                return 0;

+        if (r < 0)

+                return r;

+

+        for (;;) {

+                const char *system_name = NULL, *port_id = NULL, *port_description = NULL;

+                _cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL;

+

+                r = next_lldp_neighbor_legacy(f, &n);

+                if (r < 0)

+                        return r;

+                if (r == 0)

+                        break;

+

+                (void) sd_lldp_neighbor_get_system_name(n, &system_name);

+                (void) sd_lldp_neighbor_get_port_id_as_string(n, &port_id);

+                (void) sd_lldp_neighbor_get_port_description(n, &port_description);

+

+                r = strv_extendf(&buf, "%s on port %s%s%s%s",

+                                 strna(system_name),

+                                 strna(port_id),

+                                 isempty(port_description) ? "" : " (",

+                                 strempty(port_description),

+                                 isempty(port_description) ? "" : ")");

+                if (r < 0)

+                        return log_oom();

+        }

+

+        return dump_list(table, prefix, buf);

+}

+static int link_lldp_status_legacy(int argc, char *argv[], void *userdata) {

+        _cleanup_(sd_netlink_unrefp) sd_netlink *rtnl = NULL;

+        _cleanup_(link_info_array_freep) LinkInfo *links = NULL;

+        _cleanup_(table_unrefp) Table *table = NULL;

+        int r, c, m = 0;

+        uint16_t all = 0;

+        TableCell *cell;

+

+        r = sd_netlink_open(&rtnl);

+        if (r < 0)

+                return log_error_errno(r, "Failed to connect to netlink: %m");

+

+        c = acquire_link_info(NULL, rtnl, argc > 1 ? argv + 1 : NULL, &links);

+        if (c < 0)

+                return c;

+

+        pager_open(arg_pager_flags);

+

+        table = table_new("link",

+                          "chassis-id",

+                          "system-name",

+                          "caps",

+                          "port-id",

+                          "port-description");

+        if (!table)

+                return log_oom();

+

+        if (arg_full)

+                table_set_width(table, 0);

+

+        table_set_header(table, arg_legend);

+

+        assert_se(cell = table_get_cell(table, 0, 3));

+        table_set_minimum_width(table, cell, 11);

+        table_set_ersatz_string(table, TABLE_ERSATZ_DASH);

+

+        FOREACH_ARRAY(link, links, c) {

+                _cleanup_fclose_ FILE *f = NULL;

+

+                r = open_lldp_neighbors_legacy(link->ifindex, &f);

+                if (r == -ENOENT)

+                        continue;

+                if (r < 0) {

+                        log_warning_errno(r, "Failed to open LLDP data for %i, ignoring: %m", link->ifindex);

+                        continue;

+                }

+

+                for (;;) {

+                        const char *chassis_id = NULL, *port_id = NULL, *system_name = NULL, *port_description = NULL;

+                        _cleanup_(sd_lldp_neighbor_unrefp) sd_lldp_neighbor *n = NULL;

+                        _cleanup_free_ char *capabilities = NULL;

+                        uint16_t cc;

+

+                        r = next_lldp_neighbor_legacy(f, &n);

+                        if (r < 0) {

+                                log_warning_errno(r, "Failed to read neighbor data: %m");

+                                break;

+                        }

+                        if (r == 0)

+                                break;

+

+                        (void) sd_lldp_neighbor_get_chassis_id_as_string(n, &chassis_id);

+                        (void) sd_lldp_neighbor_get_port_id_as_string(n, &port_id);

+                        (void) sd_lldp_neighbor_get_system_name(n, &system_name);

+                        (void) sd_lldp_neighbor_get_port_description(n, &port_description);

+

+                        if (sd_lldp_neighbor_get_enabled_capabilities(n, &cc) >= 0) {

+                                capabilities = lldp_capabilities_to_string(cc);

+                                all |= cc;

+                        }

+

+                        r = table_add_many(table,

+                                           TABLE_STRING, link->name,

+                                           TABLE_STRING, chassis_id,

+                                           TABLE_STRING, system_name,

+                                           TABLE_STRING, capabilities,

+                                           TABLE_STRING, port_id,

+                                           TABLE_STRING, port_description);

+                        if (r < 0)

+                                return table_log_add_error(r);

+

+                        m++;

+                }

+        }

+

+        r = table_print(table, NULL);

+        if (r < 0)

+                return table_log_print_error(r);

+

+        if (arg_legend) {

+                lldp_capabilities_legend(all);

+                printf("\n%i neighbors listed.\n", m);

+        }

+

+        return 0;

+}

+

 int link_lldp_status(int argc, char *argv[], void *userdata) {

         _cleanup_(sd_varlink_flush_close_unrefp) sd_varlink *vl = NULL;

         _cleanup_(table_unrefp) Table *table = NULL;

@@ -224,8 +416,10 @@ int link_lldp_status(int argc, char *argv[], void *userdata) {

         int r;

         r = varlink_connect_networkd(&vl);

-        if (r < 0)

-                return r;

+        if (r < 0) {

+                log_warning("Varlink connection failed, fallback to D-Bus.");

+                return link_lldp_status_legacy(argc, argv, userdata);

+        }

         r = varlink_call_and_log(vl, "io.systemd.Network.GetLLDPNeighbors", NULL, &reply);

         if (r < 0)

diff --git a/src/network/networkctl-lldp.h b/src/network/networkctl-lldp.h

index 3ec6fe76c1..9828847924 100644

--- a/src/network/networkctl-lldp.h

+++ b/src/network/networkctl-lldp.h

@@ -7,3 +7,4 @@

 int dump_lldp_neighbors(sd_varlink *vl, Table *table, int ifindex);

 int link_lldp_status(int argc, char *argv[], void *userdata);

+int dump_lldp_neighbors_legacy(Table *table, const char *prefix, int ifindex);

diff --git a/src/network/networkctl-status-link.c b/src/network/networkctl-status-link.c

index ae13eba9ae..fbda880e9c 100644

--- a/src/network/networkctl-status-link.c

+++ b/src/network/networkctl-status-link.c

@@ -267,7 +267,6 @@ static int link_status_one(

         assert(bus);

         assert(rtnl);

-        assert(vl);

         assert(info);

         (void) sd_network_link_get_operational_state(info->ifindex, &operational_state);

@@ -904,7 +903,7 @@ static int link_status_one(

                         return table_log_add_error(r);

         }

-        r = dump_lldp_neighbors(vl, table, info->ifindex);

+        r = vl ? dump_lldp_neighbors(vl, table, info->ifindex) : dump_lldp_neighbors_legacy(table, "Connected To", info->ifindex);

         if (r < 0)

                 return r;

@@ -955,8 +954,10 @@ int link_status(int argc, char *argv[], void *userdata) {

                 log_debug_errno(r, "Failed to open hardware database: %m");

         r = varlink_connect_networkd(&vl);

-        if (r < 0)

-                return r;

+        if (r < 0) {

+                log_warning("Varlink connection failed, fallback to D-Bus.");

+                vl = NULL;

+        }

         if (arg_all)

                 c = acquire_link_info(bus, rtnl, NULL, &links);

diff --git a/src/network/networkctl-util.c b/src/network/networkctl-util.c

index 88620aad53..8bda6b1aec 100644

--- a/src/network/networkctl-util.c

+++ b/src/network/networkctl-util.c

@@ -90,7 +90,7 @@ int acquire_bus(sd_bus **ret) {

         if (networkd_is_running()) {

                 r = varlink_connect_networkd(/* ret_varlink = */ NULL);

                 if (r < 0)

-                        return r;

+                        log_warning("Varlink connection failed, fallback to D-Bus.");

         } else

                 log_warning("systemd-networkd is not running, output might be incomplete.");

diff --git a/src/systemd/sd-lldp-rx.h b/src/systemd/sd-lldp-rx.h

index 51b9f39482..b697643a07 100644

--- a/src/systemd/sd-lldp-rx.h

+++ b/src/systemd/sd-lldp-rx.h

@@ -88,6 +88,7 @@ int sd_lldp_neighbor_get_port_description(sd_lldp_neighbor *n, const char **ret)

 int sd_lldp_neighbor_get_mud_url(sd_lldp_neighbor *n, const char **ret);

 int sd_lldp_neighbor_get_system_capabilities(sd_lldp_neighbor *n, uint16_t *ret);

 int sd_lldp_neighbor_get_enabled_capabilities(sd_lldp_neighbor *n, uint16_t *ret);

+int sd_lldp_neighbor_from_raw(sd_lldp_neighbor **ret, const void *raw, size_t raw_size);

 /* Low-level, iterative TLV access. This is for everything else, it iteratively goes through all available TLVs

  * (including the ones covered with the calls above), and allows multiple TLVs for the same fields. */

-- 

2.47.1