1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
22 #include <netinet/ether.h>
23 #include <linux/netdevice.h>
28 #include "link-config.h"
29 #include "ethtool-util.h"
31 #include "libudev-private.h"
36 #include "path-util.h"
37 #include "conf-parser.h"
38 #include "conf-files.h"
41 #include "rtnl-util.h"
42 #include "network-internal.h"
43 #include "siphash24.h"
45 struct link_config_ctx {
46 LIST_HEAD(link_config, links);
50 bool enable_name_policy;
54 usec_t link_dirs_ts_usec;
57 static const char* const link_dirs[] = {
58 "/etc/systemd/network",
59 "/run/systemd/network",
60 "/usr/lib/systemd/network",
62 "/lib/systemd/network",
66 DEFINE_TRIVIAL_CLEANUP_FUNC(link_config_ctx*, link_config_ctx_free);
67 #define _cleanup_link_config_ctx_free_ _cleanup_(link_config_ctx_freep)
69 int link_config_ctx_new(link_config_ctx **ret) {
70 _cleanup_link_config_ctx_free_ link_config_ctx *ctx = NULL;
75 ctx = new0(link_config_ctx, 1);
79 LIST_HEAD_INIT(ctx->links);
83 ctx->enable_name_policy = true;
91 static void link_configs_free(link_config_ctx *ctx) {
92 link_config *link, *link_next;
97 LIST_FOREACH_SAFE(links, link, link_next, ctx->links) {
100 free(link->match_path);
101 free(link->match_driver);
102 free(link->match_type);
103 free(link->description);
105 free(link->name_policy);
111 void link_config_ctx_free(link_config_ctx *ctx) {
115 safe_close(ctx->ethtool_fd);
117 sd_rtnl_unref(ctx->rtnl);
119 link_configs_free(ctx);
126 static int load_link(link_config_ctx *ctx, const char *filename) {
127 _cleanup_free_ link_config *link = NULL;
128 _cleanup_fclose_ FILE *file = NULL;
134 file = fopen(filename, "re");
142 if (null_or_empty_fd(fileno(file))) {
143 log_debug("Skipping empty file: %s", filename);
147 link = new0(link_config, 1);
151 link->mac_policy = _MACPOLICY_INVALID;
152 link->wol = _WOL_INVALID;
153 link->duplex = _DUP_INVALID;
155 r = config_parse(NULL, filename, file,
156 "Match\0Link\0Ethernet\0",
157 config_item_perf_lookup, link_config_gperf_lookup,
158 false, false, true, link);
162 log_debug("Parsed configuration file %s", filename);
164 link->filename = strdup(filename);
166 LIST_PREPEND(links, ctx->links, link);
172 static bool enable_name_policy(void) {
173 _cleanup_free_ char *line = NULL;
174 const char *word, *state;
178 r = proc_cmdline(&line);
180 log_warning_errno(r, "Failed to read /proc/cmdline, ignoring: %m");
184 FOREACH_WORD_QUOTED(word, l, line, state)
185 if (strneq(word, "net.ifnames=0", l))
191 int link_config_load(link_config_ctx *ctx) {
193 _cleanup_strv_free_ char **files;
196 link_configs_free(ctx);
198 if (!enable_name_policy()) {
199 ctx->enable_name_policy = false;
200 log_info("Network interface NamePolicy= disabled on kernel command line, ignoring.");
203 /* update timestamp */
204 paths_check_timestamp(link_dirs, &ctx->link_dirs_ts_usec, true);
206 r = conf_files_list_strv(&files, ".link", NULL, link_dirs);
208 return log_error_errno(r, "failed to enumerate link files: %m");
210 STRV_FOREACH_BACKWARDS(f, files) {
211 r = load_link(ctx, *f);
219 bool link_config_should_reload(link_config_ctx *ctx) {
220 return paths_check_timestamp(link_dirs, &ctx->link_dirs_ts_usec, false);
223 int link_config_get(link_config_ctx *ctx, struct udev_device *device,
227 LIST_FOREACH(links, link, ctx->links) {
228 const char* attr_value;
230 attr_value = udev_device_get_sysattr_value(device, "address");
232 if (net_match_config(link->match_mac, link->match_path, link->match_driver,
233 link->match_type, link->match_name, link->match_host,
234 link->match_virt, link->match_kernel, link->match_arch,
235 attr_value ? ether_aton(attr_value) : NULL,
236 udev_device_get_property_value(device, "ID_PATH"),
237 udev_device_get_driver(udev_device_get_parent(device)),
238 udev_device_get_property_value(device, "ID_NET_DRIVER"),
239 udev_device_get_devtype(device),
240 udev_device_get_sysname(device))) {
241 if (link->match_name) {
242 unsigned char name_assign_type = NET_NAME_UNKNOWN;
244 attr_value = udev_device_get_sysattr_value(device, "name_assign_type");
246 (void)safe_atou8(attr_value, &name_assign_type);
248 if (name_assign_type == NET_NAME_ENUM) {
249 log_warning("Config file %s applies to device based on potentially unpredictable interface name '%s'",
250 link->filename, udev_device_get_sysname(device));
254 } else if (name_assign_type == NET_NAME_RENAMED) {
255 log_warning("Config file %s matches device based on renamed interface name '%s', ignoring",
256 link->filename, udev_device_get_sysname(device));
262 log_debug("Config file %s applies to device %s",
263 link->filename, udev_device_get_sysname(device));
276 static bool mac_is_random(struct udev_device *device) {
281 /* if we can't get the assign type, assume it is not random */
282 s = udev_device_get_sysattr_value(device, "addr_assign_type");
286 r = safe_atou(s, &type);
290 return type == NET_ADDR_RANDOM;
293 static bool should_rename(struct udev_device *device, bool respect_predictable) {
298 /* if we can't get the assgin type, assume we should rename */
299 s = udev_device_get_sysattr_value(device, "name_assign_type");
303 r = safe_atou(s, &type);
309 case NET_NAME_RENAMED:
310 /* these were already named by userspace, do not touch again */
312 case NET_NAME_PREDICTABLE:
313 /* the kernel claims to have given a predictable name */
314 if (respect_predictable)
319 /* the name is known to be bad, or of an unknown type */
324 static int get_mac(struct udev_device *device, bool want_random,
325 struct ether_addr *mac) {
329 random_bytes(mac->ether_addr_octet, ETH_ALEN);
333 r = net_get_unique_predictable_data(device, result);
337 assert_cc(ETH_ALEN <= sizeof(result));
338 memcpy(mac->ether_addr_octet, result, ETH_ALEN);
341 /* see eth_random_addr in the kernel */
342 mac->ether_addr_octet[0] &= 0xfe; /* clear multicast bit */
343 mac->ether_addr_octet[0] |= 0x02; /* set local assignment bit (IEEE802) */
348 int link_config_apply(link_config_ctx *ctx, link_config *config,
349 struct udev_device *device, const char **name) {
350 const char *old_name;
351 const char *new_name = NULL;
352 struct ether_addr generated_mac;
353 struct ether_addr *mac = NULL;
354 bool respect_predictable = false;
362 old_name = udev_device_get_sysname(device);
366 r = ethtool_set_speed(&ctx->ethtool_fd, old_name, config->speed / 1024,
369 log_warning_errno(r, "Could not set speed or duplex of %s to %u Mbps (%s): %m",
370 old_name, config->speed / 1024,
371 duplex_to_string(config->duplex));
373 r = ethtool_set_wol(&ctx->ethtool_fd, old_name, config->wol);
375 log_warning_errno(r, "Could not set WakeOnLan of %s to %s: %m",
376 old_name, wol_to_string(config->wol));
378 ifindex = udev_device_get_ifindex(device);
380 log_warning("Could not find ifindex");
384 if (ctx->enable_name_policy && config->name_policy) {
387 for (policy = config->name_policy;
388 !new_name && *policy != _NAMEPOLICY_INVALID; policy++) {
390 case NAMEPOLICY_KERNEL:
391 respect_predictable = true;
393 case NAMEPOLICY_DATABASE:
394 new_name = udev_device_get_property_value(device, "ID_NET_NAME_FROM_DATABASE");
396 case NAMEPOLICY_ONBOARD:
397 new_name = udev_device_get_property_value(device, "ID_NET_NAME_ONBOARD");
399 case NAMEPOLICY_SLOT:
400 new_name = udev_device_get_property_value(device, "ID_NET_NAME_SLOT");
402 case NAMEPOLICY_PATH:
403 new_name = udev_device_get_property_value(device, "ID_NET_NAME_PATH");
406 new_name = udev_device_get_property_value(device, "ID_NET_NAME_MAC");
414 if (should_rename(device, respect_predictable)) {
415 /* if not set by policy, fall back manually set name */
417 new_name = config->name;
421 switch (config->mac_policy) {
422 case MACPOLICY_PERSISTENT:
423 if (mac_is_random(device)) {
424 r = get_mac(device, false, &generated_mac);
429 mac = &generated_mac;
432 case MACPOLICY_RANDOM:
433 if (!mac_is_random(device)) {
434 r = get_mac(device, true, &generated_mac);
439 mac = &generated_mac;
446 r = rtnl_set_link_properties(&ctx->rtnl, ifindex, config->alias, mac,
449 return log_warning_errno(r, "Could not set Alias, MACAddress or MTU on %s: %m", old_name);
456 int link_get_driver(link_config_ctx *ctx, struct udev_device *device, char **ret) {
461 name = udev_device_get_sysname(device);
465 r = ethtool_get_driver(&ctx->ethtool_fd, name, &driver);
473 static const char* const mac_policy_table[_MACPOLICY_MAX] = {
474 [MACPOLICY_PERSISTENT] = "persistent",
475 [MACPOLICY_RANDOM] = "random"
478 DEFINE_STRING_TABLE_LOOKUP(mac_policy, MACPolicy);
479 DEFINE_CONFIG_PARSE_ENUM(config_parse_mac_policy, mac_policy, MACPolicy,
480 "Failed to parse MAC address policy");
482 static const char* const name_policy_table[_NAMEPOLICY_MAX] = {
483 [NAMEPOLICY_KERNEL] = "kernel",
484 [NAMEPOLICY_DATABASE] = "database",
485 [NAMEPOLICY_ONBOARD] = "onboard",
486 [NAMEPOLICY_SLOT] = "slot",
487 [NAMEPOLICY_PATH] = "path",
488 [NAMEPOLICY_MAC] = "mac"
491 DEFINE_STRING_TABLE_LOOKUP(name_policy, NamePolicy);
492 DEFINE_CONFIG_PARSE_ENUMV(config_parse_name_policy, name_policy, NamePolicy,
494 "Failed to parse interface name policy");