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systemd / systemd / 14013585018

22 Mar 2025 03:54PM UTC coverage: 71.951% (+0.002%) from 71.949%
14013585018

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some dbus property fixes (#36830)

4 of 4 new or added lines in 1 file covered. (100.0%)

145 existing lines in 35 files now uncovered.

296620 of 412255 relevant lines covered (71.95%)

737629.16 hits per line

Source File
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81.98
/src/network/networkd-sysctl.c
1
/* SPDX-License-Identifier: LGPL-2.1-or-later */
2

3
#include <netinet/in.h>
4
#include <linux/if.h>
5
#include <linux/if_arp.h>
6

7
#include "sd-messages.h"
8

9
#include "af-list.h"
10
#include "cgroup-util.h"
11
#include "event-util.h"
12
#include "fd-util.h"
13
#include "format-util.h"
14
#include "missing_network.h"
15
#include "networkd-link.h"
16
#include "networkd-lldp-tx.h"
17
#include "networkd-manager.h"
18
#include "networkd-ndisc.h"
19
#include "networkd-network.h"
20
#include "networkd-sysctl.h"
21
#include "path-util.h"
22
#include "socket-util.h"
23
#include "string-table.h"
24
#include "sysctl-util.h"
25

26
#if HAVE_VMLINUX_H
27

28
#include "bpf-link.h"
29

30
#include "bpf/sysctl_monitor/sysctl-monitor-skel.h"
31
#include "bpf/sysctl_monitor/sysctl-write-event.h"
32

33
static struct sysctl_monitor_bpf* sysctl_monitor_bpf_free(struct sysctl_monitor_bpf *obj) {
440✔
34
        sysctl_monitor_bpf__destroy(obj);
440✔
35
        return NULL;
440✔
36
}
37

38
DEFINE_TRIVIAL_CLEANUP_FUNC(struct sysctl_monitor_bpf *, sysctl_monitor_bpf_free);
416✔
39

40
static int sysctl_event_handler(void *ctx, void *data, size_t data_sz) {
1✔
41
        struct sysctl_write_event *we = ASSERT_PTR(data);
1✔
42
        Hashmap **sysctl_shadow = ASSERT_PTR(ctx);
1✔
43
        _cleanup_free_ char *path = NULL;
1✔
44
        char *value;
1✔
45

46
        /* Returning a negative value interrupts the ring buffer polling,
47
         * so do it only in case of a fatal error like a version mismatch. */
48
        if (we->version != 1)
1✔
49
                return log_warning_errno(SYNTHETIC_ERRNO(EINVAL),
×
50
                                         "Unexpected sysctl event, disabling sysctl monitoring: %d", we->version);
51

52
        if (we->errorcode != 0) {
1✔
53
                log_warning_errno(we->errorcode, "Sysctl monitor BPF returned error: %m");
×
54
                return 0;
×
55
        }
56

57
        path = path_join("/proc/sys", we->path);
1✔
58
        if (!path) {
1✔
59
                log_oom_warning();
×
60
                return 0;
61
        }
62

63
        /* If we never managed this handle, ignore it. */
64
        value = hashmap_get(*sysctl_shadow, path);
1✔
65
        if (!value)
1✔
66
                return 0;
67

68
        if (!strneq(value, we->newvalue, sizeof(we->newvalue)))
×
69
                log_struct(LOG_WARNING,
×
70
                           "MESSAGE_ID=" SD_MESSAGE_SYSCTL_CHANGED_STR,
71
                           "OBJECT_PID=" PID_FMT, we->pid,
72
                           "OBJECT_COMM=%s", we->comm,
73
                           "SYSCTL=%s", path,
74
                           "OLDVALUE=%s", we->current,
75
                           "NEWVALUE=%s", we->newvalue,
76
                           "OURVALUE=%s", value,
77
                           LOG_MESSAGE("Foreign process '%s[" PID_FMT "]' changed sysctl '%s' from '%s' to '%s', conflicting with our setting to '%s'.",
78
                                       we->comm, we->pid, path, we->current, we->newvalue, value));
79

80
        return 0;
81
}
82

83
static int on_ringbuf_io(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
1✔
84
        struct ring_buffer *rb = ASSERT_PTR(userdata);
1✔
85
        int r;
1✔
86

87
        r = sym_ring_buffer__poll(rb, /* timeout_msec= */ 0);
1✔
88
        if (r < 0 && errno != EINTR)
1✔
89
                log_error_errno(errno, "Error polling ring buffer: %m");
×
90

91
        return 0;
1✔
92
}
93

94
int manager_install_sysctl_monitor(Manager *manager) {
416✔
95
        _cleanup_(sysctl_monitor_bpf_freep) struct sysctl_monitor_bpf *obj = NULL;
416✔
96
        _cleanup_(bpf_link_freep) struct bpf_link *sysctl_link = NULL;
416✔
97
        _cleanup_(bpf_ring_buffer_freep) struct ring_buffer *sysctl_buffer = NULL;
×
98
        _cleanup_close_ int cgroup_fd = -EBADF, root_cgroup_fd = -EBADF;
832✔
99
        _cleanup_free_ char *cgroup = NULL;
416✔
100
        int idx = 0, r, fd;
416✔
101

102
        assert(manager);
416✔
103

104
        r = dlopen_bpf();
416✔
105
        if (ERRNO_IS_NEG_NOT_SUPPORTED(r))
416✔
106
                return log_debug_errno(r, "sysctl monitor disabled, as BPF support is not available.");
×
107
        if (r < 0)
416✔
108
                return log_warning_errno(r, "Failed to load libbpf, not installing sysctl monitor: %m");
×
109

110
        r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &cgroup);
416✔
111
        if (r < 0)
416✔
112
                return log_warning_errno(r, "Failed to get cgroup path, ignoring: %m.");
×
113

114
        root_cgroup_fd = cg_path_open(SYSTEMD_CGROUP_CONTROLLER, "/");
416✔
115
        if (root_cgroup_fd < 0)
416✔
116
                return log_warning_errno(root_cgroup_fd, "Failed to open cgroup, ignoring: %m");
×
117

118
        obj = sysctl_monitor_bpf__open_and_load();
416✔
119
        if (!obj)
416✔
120
                return log_full_errno(errno == EINVAL ? LOG_DEBUG : LOG_INFO, errno,
112✔
121
                                      "Unable to load sysctl monitor BPF program, ignoring: %m");
122

123
        cgroup_fd = cg_path_open(SYSTEMD_CGROUP_CONTROLLER, cgroup);
360✔
124
        if (cgroup_fd < 0)
360✔
125
                return log_warning_errno(cgroup_fd, "Failed to open cgroup: %m");
×
126

127
        if (sym_bpf_map_update_elem(sym_bpf_map__fd(obj->maps.cgroup_map), &idx, &cgroup_fd, BPF_ANY))
360✔
128
                return log_warning_errno(errno, "Failed to update cgroup map: %m");
×
129

130
        sysctl_link = sym_bpf_program__attach_cgroup(obj->progs.sysctl_monitor, root_cgroup_fd);
360✔
131
        r = bpf_get_error_translated(sysctl_link);
360✔
132
        if (r < 0)
360✔
133
                return log_warning_errno(r, "Unable to attach sysctl monitor BPF program to cgroup, ignoring: %m");
×
134

135
        fd = sym_bpf_map__fd(obj->maps.written_sysctls);
360✔
136
        if (fd < 0)
360✔
137
                return log_warning_errno(fd, "Failed to get fd of sysctl maps: %m");
×
138

139
        sysctl_buffer = sym_ring_buffer__new(fd, sysctl_event_handler, &manager->sysctl_shadow, NULL);
360✔
140
        if (!sysctl_buffer)
360✔
141
                return log_warning_errno(errno, "Failed to create ring buffer: %m");
×
142

143
        fd = sym_ring_buffer__epoll_fd(sysctl_buffer);
360✔
144
        if (fd < 0)
360✔
145
                return log_warning_errno(fd, "Failed to get poll fd of ring buffer: %m");
×
146

147
        r = sd_event_add_io(manager->event, &manager->sysctl_event_source,
360✔
148
                            fd, EPOLLIN, on_ringbuf_io, sysctl_buffer);
149
        if (r < 0)
360✔
150
                return log_warning_errno(r, "Failed to watch sysctl event ringbuffer: %m");
×
151

152
        manager->sysctl_link = TAKE_PTR(sysctl_link);
360✔
153
        manager->sysctl_skel = TAKE_PTR(obj);
360✔
154
        manager->sysctl_buffer = TAKE_PTR(sysctl_buffer);
360✔
155
        manager->cgroup_fd = TAKE_FD(cgroup_fd);
360✔
156

157
        return 0;
360✔
158
}
159

160
void manager_remove_sysctl_monitor(Manager *manager) {
440✔
161
        assert(manager);
440✔
162

163
        manager->sysctl_event_source = sd_event_source_disable_unref(manager->sysctl_event_source);
440✔
164
        manager->sysctl_buffer = bpf_ring_buffer_free(manager->sysctl_buffer);
440✔
165
        manager->sysctl_link = bpf_link_free(manager->sysctl_link);
440✔
166
        manager->sysctl_skel = sysctl_monitor_bpf_free(manager->sysctl_skel);
440✔
167
        manager->cgroup_fd = safe_close(manager->cgroup_fd);
440✔
168
        manager->sysctl_shadow = hashmap_free(manager->sysctl_shadow);
440✔
169
}
440✔
170

171
int link_clear_sysctl_shadows(Link *link) {
2,580✔
172
        _cleanup_free_ char *ipv4 = NULL, *ipv6 = NULL;
2,580✔
173
        char *key = NULL, *value = NULL;
2,580✔
174

175
        assert(link);
2,580✔
176
        assert(link->manager);
2,580✔
177

178
        ipv4 = path_join("/proc/sys/net/ipv4/conf", link->ifname);
2,580✔
179
        if (!ipv4)
2,580✔
180
                return log_oom();
×
181

182
        ipv6 = path_join("/proc/sys/net/ipv6/conf", link->ifname);
2,580✔
183
        if (!ipv6)
2,580✔
184
                return log_oom();
×
185

186
        HASHMAP_FOREACH_KEY(value, key, link->manager->sysctl_shadow)
8,215✔
187
                if (path_startswith(key, ipv4) || path_startswith(key, ipv6)) {
5,635✔
188
                        assert_se(hashmap_remove_value(link->manager->sysctl_shadow, key, value));
2,696✔
189
                        free(key);
2,696✔
190
                        free(value);
2,696✔
191
                }
192

193
        return 0;
2,580✔
194
}
195
#endif
196

197
static void manager_set_ip_forwarding(Manager *manager, int family) {
834✔
198
        int r, t;
834✔
199

200
        assert(manager);
834✔
201
        assert(IN_SET(family, AF_INET, AF_INET6));
834✔
202

203
        if (family == AF_INET6 && !socket_ipv6_is_supported())
834✔
204
                return;
205

206
        t = manager->ip_forwarding[family == AF_INET6];
834✔
207
        if (t < 0)
834✔
208
                return; /* keep */
209

210
        /* First, set the default value. */
211
        r = sysctl_write_ip_property_boolean(family, "default", "forwarding", t, manager_get_sysctl_shadow(manager));
2✔
212
        if (r < 0)
2✔
213
                log_warning_errno(r, "Failed to %s the default %s forwarding: %m",
×
214
                                  enable_disable(t), af_to_ipv4_ipv6(family));
215

216
        /* Then, set the value to all interfaces. */
217
        r = sysctl_write_ip_property_boolean(family, "all", "forwarding", t, manager_get_sysctl_shadow(manager));
2✔
218
        if (r < 0)
2✔
219
                log_warning_errno(r, "Failed to %s %s forwarding for all interfaces: %m",
×
220
                                  enable_disable(t), af_to_ipv4_ipv6(family));
221
}
222

223
void manager_set_sysctl(Manager *manager) {
416✔
224
        assert(manager);
416✔
225
        assert(!manager->test_mode);
416✔
226

227
        manager_set_ip_forwarding(manager, AF_INET);
416✔
228
        manager_set_ip_forwarding(manager, AF_INET6);
416✔
229
}
416✔
230

231
static bool link_is_configured_for_family(Link *link, int family) {
15,712✔
232
        assert(link);
15,712✔
233

234
        if (!link->network)
15,712✔
235
                return false;
236

237
        if (link->flags & IFF_LOOPBACK)
15,712✔
238
                return false;
239

240
        /* CAN devices do not support IP layer. Most of the functions below are never called for CAN devices,
241
         * but link_set_ipv6_mtu() may be called after setting interface MTU, and warn about the failure. For
242
         * safety, let's unconditionally check if the interface is not a CAN device. */
243
        if (IN_SET(family, AF_INET, AF_INET6, AF_MPLS) && link->iftype == ARPHRD_CAN)
15,712✔
244
                return false;
245

246
        if (family == AF_INET6 && !socket_ipv6_is_supported())
15,708✔
247
                return false;
×
248

249
        return true;
250
}
251

252
static int link_update_ipv6_sysctl(Link *link) {
753✔
253
        assert(link);
753✔
254
        assert(link->manager);
753✔
255

256
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
257
                return 0;
258

259
        if (!link_ipv6_enabled(link))
753✔
260
                return 0;
261

262
        return sysctl_write_ip_property_boolean(AF_INET6, link->ifname, "disable_ipv6", false, manager_get_sysctl_shadow(link->manager));
694✔
263
}
264

265
static int link_set_proxy_arp(Link *link) {
753✔
266
        assert(link);
753✔
267
        assert(link->manager);
753✔
268

269
        if (!link_is_configured_for_family(link, AF_INET))
753✔
270
                return 0;
271

272
        if (link->network->proxy_arp < 0)
753✔
273
                return 0;
274

275
        return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "proxy_arp", link->network->proxy_arp > 0, manager_get_sysctl_shadow(link->manager));
2✔
276
}
277

278
static int link_set_proxy_arp_pvlan(Link *link) {
753✔
279
        assert(link);
753✔
280
        assert(link->manager);
753✔
281

282
        if (!link_is_configured_for_family(link, AF_INET))
753✔
283
                return 0;
284

285
        if (link->network->proxy_arp_pvlan < 0)
753✔
286
                return 0;
287

288
        return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "proxy_arp_pvlan", link->network->proxy_arp_pvlan > 0, manager_get_sysctl_shadow(link->manager));
2✔
289
}
290

291
int link_get_ip_forwarding(Link *link, int family) {
1,989✔
292
        assert(link);
1,989✔
293
        assert(link->manager);
1,989✔
294
        assert(link->network);
1,989✔
295
        assert(IN_SET(family, AF_INET, AF_INET6));
1,989✔
296

297
        /* If it is explicitly specified, then honor the setting. */
298
        int t = link->network->ip_forwarding[family == AF_INET6];
1,989✔
299
        if (t >= 0)
1,989✔
300
                return t;
301

302
        /* If IPMasquerade= is enabled, also enable IP forwarding. */
303
        if (FLAGS_SET(link->network->ip_masquerade, AF_TO_ADDRESS_FAMILY(family)))
3,107✔
304
                return true;
305

306
        /* If IPv6SendRA= is enabled, also enable IPv6 forwarding. */
307
        if (family == AF_INET6 && link_radv_enabled(link))
1,892✔
308
                return true;
309

310
        /* Otherwise, use the global setting. */
311
        return link->manager->ip_forwarding[family == AF_INET6];
1,862✔
312
}
313

314
static int link_set_ip_forwarding_impl(Link *link, int family) {
1,506✔
315
        int r, t;
1,506✔
316

317
        assert(link);
1,506✔
318
        assert(link->manager);
1,506✔
319
        assert(IN_SET(family, AF_INET, AF_INET6));
1,506✔
320

321
        if (!link_is_configured_for_family(link, family))
1,506✔
322
                return 0;
323

324
        t = link_get_ip_forwarding(link, family);
1,506✔
325
        if (t < 0)
1,506✔
326
                return 0; /* keep */
327

328
        r = sysctl_write_ip_property_boolean(family, link->ifname, "forwarding", t, manager_get_sysctl_shadow(link->manager));
112✔
329
        if (r < 0)
112✔
330
                return log_link_warning_errno(link, r, "Failed to %s %s forwarding, ignoring: %m",
×
331
                                              enable_disable(t), af_to_ipv4_ipv6(family));
332

333
        return 0;
334
}
335

336
static int link_reapply_ip_forwarding(Link *link, int family) {
4✔
337
        int r, ret = 0;
4✔
338

339
        assert(link);
4✔
340
        assert(IN_SET(family, AF_INET, AF_INET6));
4✔
341

342
        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
4✔
343
                return 0;
4✔
344

345
        (void) link_set_ip_forwarding_impl(link, family);
2✔
346

347
        r = link_lldp_tx_update_capabilities(link);
2✔
348
        if (r < 0)
2✔
349
                RET_GATHER(ret, log_link_warning_errno(link, r, "Could not update LLDP capabilities, ignoring: %m"));
×
350

351
        if (family == AF_INET6 && !link_ndisc_enabled(link)) {
2✔
352
                r = ndisc_stop(link);
1✔
353
                if (r < 0)
1✔
354
                        RET_GATHER(ret, log_link_warning_errno(link, r, "Could not stop IPv6 Router Discovery, ignoring: %m"));
×
355

356
                ndisc_flush(link);
1✔
357
        }
358

359
        return ret;
360
}
361

362
static int link_set_ip_forwarding(Link *link, int family) {
1,506✔
363
        int r;
1,506✔
364

365
        assert(link);
1,506✔
366
        assert(link->manager);
1,506✔
367
        assert(link->network);
1,506✔
368
        assert(IN_SET(family, AF_INET, AF_INET6));
1,506✔
369

370
        if (!link_is_configured_for_family(link, family))
1,506✔
371
                return 0;
372

373
        /* When IPMasquerade= is enabled and the global setting is unset, enable _global_ IP forwarding, and
374
         * re-apply per-link setting for all links. */
375
        if (FLAGS_SET(link->network->ip_masquerade, AF_TO_ADDRESS_FAMILY(family)) &&
2,259✔
376
            link->manager->ip_forwarding[family == AF_INET6] < 0) {
28✔
377

378
                link->manager->ip_forwarding[family == AF_INET6] = true;
2✔
379
                manager_set_ip_forwarding(link->manager, family);
2✔
380

381
                Link *other;
2✔
382
                HASHMAP_FOREACH(other, link->manager->links_by_index) {
8✔
383
                        r = link_reapply_ip_forwarding(other, family);
4✔
384
                        if (r < 0)
4✔
385
                                link_enter_failed(other);
×
386
                }
387

388
                return 0;
2✔
389
        }
390

391
        /* Otherwise, apply per-link setting for _this_ link. */
392
        return link_set_ip_forwarding_impl(link, family);
1,504✔
393
}
394

395
static int link_set_ipv4_rp_filter(Link *link) {
753✔
396
        assert(link);
753✔
397
        assert(link->manager);
753✔
398

399
        if (!link_is_configured_for_family(link, AF_INET))
753✔
400
                return 0;
401

402
        if (link->network->ipv4_rp_filter < 0)
753✔
403
                return 0;
404

405
        return sysctl_write_ip_property_int(AF_INET, link->ifname, "rp_filter", link->network->ipv4_rp_filter, manager_get_sysctl_shadow(link->manager));
2✔
406
}
407

408
static int link_set_ipv4_force_igmp_version(Link *link) {
753✔
409
        assert(link);
753✔
410

411
        if (!link_is_configured_for_family(link, AF_INET))
753✔
412
                return 0;
413

414
        if (link->network->ipv4_force_igmp_version < 0)
753✔
415
                return 0;
416

417
        return sysctl_write_ip_property_int(AF_INET, link->ifname, "force_igmp_version", link->network->ipv4_force_igmp_version, manager_get_sysctl_shadow(link->manager));
2✔
418
}
419

420
static int link_set_ipv6_privacy_extensions(Link *link) {
753✔
421
        IPv6PrivacyExtensions val;
753✔
422

423
        assert(link);
753✔
424
        assert(link->manager);
753✔
425

426
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
427
                return 0;
428

429
        val = link->network->ipv6_privacy_extensions;
753✔
430
        if (val < 0) /* If not specified, then use the global setting. */
753✔
431
                val = link->manager->ipv6_privacy_extensions;
728✔
432

433
        /* When "kernel", do not update the setting. */
434
        if (val == IPV6_PRIVACY_EXTENSIONS_KERNEL)
753✔
435
                return 0;
436

437
        return sysctl_write_ip_property_int(AF_INET6, link->ifname, "use_tempaddr", (int) val, manager_get_sysctl_shadow(link->manager));
753✔
438
}
439

440
static int link_set_ipv6_accept_ra(Link *link) {
753✔
441
        assert(link);
753✔
442
        assert(link->manager);
753✔
443

444
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
445
                return 0;
446

447
        return sysctl_write_ip_property(AF_INET6, link->ifname, "accept_ra", "0", manager_get_sysctl_shadow(link->manager));
753✔
448
}
449

450
static int link_set_ipv6_dad_transmits(Link *link) {
753✔
451
        assert(link);
753✔
452
        assert(link->manager);
753✔
453

454
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
455
                return 0;
456

457
        if (link->network->ipv6_dad_transmits < 0)
753✔
458
                return 0;
459

460
        return sysctl_write_ip_property_int(AF_INET6, link->ifname, "dad_transmits", link->network->ipv6_dad_transmits, manager_get_sysctl_shadow(link->manager));
2✔
461
}
462

463
static int link_set_ipv6_hop_limit(Link *link) {
753✔
464
        assert(link);
753✔
465
        assert(link->manager);
753✔
466

467
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
468
                return 0;
469

470
        if (link->network->ipv6_hop_limit <= 0)
753✔
471
                return 0;
472

473
        return sysctl_write_ip_property_int(AF_INET6, link->ifname, "hop_limit", link->network->ipv6_hop_limit, manager_get_sysctl_shadow(link->manager));
2✔
474
}
475

476
static int link_set_ipv6_retransmission_time(Link *link) {
753✔
477
        usec_t retrans_time_ms;
753✔
478

479
        assert(link);
753✔
480
        assert(link->manager);
753✔
481

482
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
483
                return 0;
484

485
        if (!timestamp_is_set(link->network->ipv6_retransmission_time))
753✔
486
                return 0;
487

488
        retrans_time_ms = DIV_ROUND_UP(link->network->ipv6_retransmission_time, USEC_PER_MSEC);
2✔
489
         if (retrans_time_ms <= 0 || retrans_time_ms > UINT32_MAX)
2✔
490
                return 0;
491

492
        return sysctl_write_ip_neighbor_property_uint32(AF_INET6, link->ifname, "retrans_time_ms", retrans_time_ms, manager_get_sysctl_shadow(link->manager));
2✔
493
}
494

495
static int link_set_ipv6_proxy_ndp(Link *link) {
753✔
496
        bool v;
753✔
497

498
        assert(link);
753✔
499
        assert(link->manager);
753✔
500

501
        if (!link_is_configured_for_family(link, AF_INET6))
753✔
502
                return 0;
503

504
        if (link->network->ipv6_proxy_ndp >= 0)
753✔
505
                v = link->network->ipv6_proxy_ndp;
2✔
506
        else
507
                v = !set_isempty(link->network->ipv6_proxy_ndp_addresses);
751✔
508

509
        return sysctl_write_ip_property_boolean(AF_INET6, link->ifname, "proxy_ndp", v, manager_get_sysctl_shadow(link->manager));
1,503✔
510
}
511

512
int link_set_ipv6_mtu(Link *link, int log_level) {
1,405✔
513
        uint32_t mtu = 0;
1,405✔
514
        int r;
1,405✔
515

516
        assert(link);
1,405✔
517
        assert(link->manager);
1,405✔
518

519
        if (!link_is_configured_for_family(link, AF_INET6))
1,405✔
520
                return 0;
521

522
        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
1,401✔
523
                return 0;
524

525
        if (sd_event_source_get_enabled(link->ipv6_mtu_wait_synced_event_source, /* ret = */ NULL) > 0) {
1,401✔
526
                log_link_debug(link, "Waiting for IPv6 MTU is synced to link MTU, delaying to set IPv6 MTU.");
×
527
                return 0;
×
528
        }
529

530
        assert(link->network);
1,401✔
531

532
        if (link->network->ndisc_use_mtu)
1,401✔
533
                mtu = link->ndisc_mtu;
1,401✔
534
        if (mtu == 0)
1,401✔
535
                mtu = link->network->ipv6_mtu;
1,358✔
536
        if (mtu == 0)
1,358✔
537
                return 0;
538

539
        if (mtu > link->mtu) {
78✔
540
                log_link_full(link, log_level,
11✔
541
                              "Reducing requested IPv6 MTU %"PRIu32" to the interface's maximum MTU %"PRIu32".",
542
                              mtu, link->mtu);
543
                mtu = link->mtu;
11✔
544
        }
545

546
        r = sysctl_write_ip_property_uint32(AF_INET6, link->ifname, "mtu", mtu, manager_get_sysctl_shadow(link->manager));
78✔
547
        if (r < 0)
78✔
548
                return log_link_warning_errno(link, r, "Failed to set IPv6 MTU to %"PRIu32": %m", mtu);
×
549

550
        return 0;
551
}
552

553
static int ipv6_mtu_wait_synced_handler(sd_event_source *s, uint64_t usec, void *userdata);
554

555
static int link_set_ipv6_mtu_async_impl(Link *link) {
44✔
556
        uint32_t current_mtu;
44✔
557
        int r;
44✔
558

559
        assert(link);
44✔
560

561
        /* When the link MTU is updated, it seems that the kernel IPv6 MTU of the interface is asynchronously
562
         * reset to the link MTU. Hence, we need to check if it is already reset, and wait for a while if not. */
563

564
        if (++link->ipv6_mtu_wait_trial_count >= 10) {
44✔
565
                log_link_debug(link, "Timed out waiting for IPv6 MTU being synced to link MTU, proceeding anyway.");
×
566
                r = link_set_ipv6_mtu(link, LOG_INFO);
×
567
                if (r < 0)
×
568
                        return r;
44✔
569

570
                return 1; /* done */
×
571
        }
572

573
        /* Check if IPv6 MTU is synced. */
574
        r = sysctl_read_ip_property_uint32(AF_INET6, link->ifname, "mtu", &current_mtu);
44✔
575
        if (r < 0)
44✔
576
                return log_link_warning_errno(link, r, "Failed to read IPv6 MTU: %m");
2✔
577

578
        if (current_mtu == link->mtu) {
42✔
579
                /* Already synced. Update IPv6 MTU now. */
580
                r = link_set_ipv6_mtu(link, LOG_INFO);
42✔
581
                if (r < 0)
42✔
582
                        return r;
583

584
                return 1; /* done */
42✔
585
        }
586

587
        /* If not, set up a timer event source. */
588
        r = event_reset_time_relative(
×
589
                        link->manager->event, &link->ipv6_mtu_wait_synced_event_source,
×
590
                        CLOCK_BOOTTIME, 100 * USEC_PER_MSEC, 0,
591
                        ipv6_mtu_wait_synced_handler, link,
592
                        /* priority = */ 0, "ipv6-mtu-wait-synced", /* force = */ true);
593
        if (r < 0)
×
594
                return log_link_warning_errno(link, r, "Failed to configure timer event source for waiting for IPv6 MTU being synced: %m");
×
595

596
        /* Check again. */
597
        r = sysctl_read_ip_property_uint32(AF_INET6, link->ifname, "mtu", &current_mtu);
×
598
        if (r < 0)
×
599
                return log_link_warning_errno(link, r, "Failed to read IPv6 MTU: %m");
×
600

601
        if (current_mtu == link->mtu) {
×
602
                /* Synced while setting up the timer event source. Disable it and update IPv6 MTU now. */
603
                r = sd_event_source_set_enabled(link->ipv6_mtu_wait_synced_event_source, SD_EVENT_OFF);
×
604
                if (r < 0)
×
605
                        log_link_debug_errno(link, r, "Failed to disable timer event source for IPv6 MTU, ignoring: %m");
×
606

607
                r = link_set_ipv6_mtu(link, LOG_INFO);
×
608
                if (r < 0)
×
609
                        return r;
610

611
                return 1; /* done */
×
612
        }
613

614
        log_link_debug(link, "IPv6 MTU is not synced to the link MTU after it is changed. Waiting for a while.");
×
615
        return 0; /* waiting */
616
}
617

618
static int ipv6_mtu_wait_synced_handler(sd_event_source *s, uint64_t usec, void *userdata) {
×
619
        (void) link_set_ipv6_mtu_async_impl(ASSERT_PTR(userdata));
×
620
        return 0;
×
621
}
622

623
int link_set_ipv6_mtu_async(Link *link) {
44✔
624
        assert(link);
44✔
625

626
        link->ipv6_mtu_wait_trial_count = 0;
44✔
627
        return link_set_ipv6_mtu_async_impl(link);
44✔
628
}
629

630
static int link_set_ipv4_accept_local(Link *link) {
753✔
631
        assert(link);
753✔
632
        assert(link->manager);
753✔
633

634
        if (!link_is_configured_for_family(link, AF_INET))
753✔
635
                return 0;
636

637
        if (link->network->ipv4_accept_local < 0)
753✔
638
                return 0;
639

640
        return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "accept_local", link->network->ipv4_accept_local > 0, manager_get_sysctl_shadow(link->manager));
2✔
641
}
642

643
static int link_set_ipv4_route_localnet(Link *link) {
753✔
644
        assert(link);
753✔
645
        assert(link->manager);
753✔
646

647
        if (!link_is_configured_for_family(link, AF_INET))
753✔
648
                return 0;
649

650
        if (link->network->ipv4_route_localnet < 0)
753✔
651
                return 0;
652

653
        return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "route_localnet", link->network->ipv4_route_localnet > 0, manager_get_sysctl_shadow(link->manager));
×
654
}
655

656
static int link_set_ipv4_promote_secondaries(Link *link) {
753✔
657
        assert(link);
753✔
658
        assert(link->manager);
753✔
659

660
        if (!link_is_configured_for_family(link, AF_INET))
753✔
661
                return 0;
662

663
        /* If promote_secondaries is not set, DHCP will work only as long as the IP address does not
664
         * changes between leases. The kernel will remove all secondary IP addresses of an interface
665
         * otherwise. The way systemd-networkd works is that the new IP of a lease is added as a
666
         * secondary IP and when the primary one expires it relies on the kernel to promote the
667
         * secondary IP. See also https://github.com/systemd/systemd/issues/7163 */
668
        return sysctl_write_ip_property_boolean(AF_INET, link->ifname, "promote_secondaries", true, manager_get_sysctl_shadow(link->manager));
753✔
669
}
670

671
static int link_set_mpls_input(Link *link) {
753✔
672
        assert(link);
753✔
673
        assert(link->manager);
753✔
674

675
        if (!link_is_configured_for_family(link, AF_MPLS))
753✔
676
                return 0;
677

678
        if (link->network->mpls_input < 0)
753✔
679
                return 0;
680

681
        return sysctl_write_ip_property_boolean(AF_MPLS, link->ifname, "input", link->network->mpls_input > 0, manager_get_sysctl_shadow(link->manager));
1✔
682
}
683

684
int link_set_sysctl(Link *link) {
753✔
685
        int r;
753✔
686

687
        assert(link);
753✔
688

689
        /* If IPv6 configured that is static IPv6 address and IPv6LL autoconfiguration is enabled
690
         * for this interface, then enable IPv6 */
691
        r = link_update_ipv6_sysctl(link);
753✔
692
        if (r < 0)
753✔
UNCOV
693
                log_link_warning_errno(link, r, "Cannot enable IPv6, ignoring: %m");
×
694

695
        r = link_set_proxy_arp(link);
753✔
696
        if (r < 0)
753✔
697
               log_link_warning_errno(link, r, "Cannot configure proxy ARP for interface, ignoring: %m");
×
698

699
        r = link_set_proxy_arp_pvlan(link);
753✔
700
        if (r < 0)
753✔
701
                log_link_warning_errno(link, r, "Cannot configure proxy ARP private VLAN for interface, ignoring: %m");
×
702

703
        (void) link_set_ip_forwarding(link, AF_INET);
753✔
704
        (void) link_set_ip_forwarding(link, AF_INET6);
753✔
705

706
        r = link_set_ipv6_privacy_extensions(link);
753✔
707
        if (r < 0)
753✔
UNCOV
708
                log_link_warning_errno(link, r, "Cannot configure IPv6 privacy extensions for interface, ignoring: %m");
×
709

710
        r = link_set_ipv6_accept_ra(link);
753✔
711
        if (r < 0)
753✔
UNCOV
712
                log_link_warning_errno(link, r, "Cannot disable kernel IPv6 accept_ra for interface, ignoring: %m");
×
713

714
        r = link_set_ipv6_dad_transmits(link);
753✔
715
        if (r < 0)
753✔
716
                log_link_warning_errno(link, r, "Cannot set IPv6 dad transmits for interface, ignoring: %m");
×
717

718
        r = link_set_ipv6_hop_limit(link);
753✔
719
        if (r < 0)
753✔
720
                log_link_warning_errno(link, r, "Cannot set IPv6 hop limit for interface, ignoring: %m");
×
721

722
        r = link_set_ipv6_retransmission_time(link);
753✔
723
        if (r < 0)
753✔
724
                log_link_warning_errno(link, r, "Cannot set IPv6 retransmission time for interface, ignoring: %m");
×
725

726
        r = link_set_ipv6_proxy_ndp(link);
753✔
727
        if (r < 0)
753✔
UNCOV
728
                log_link_warning_errno(link, r, "Cannot set IPv6 proxy NDP, ignoring: %m");
×
729

730
        (void) link_set_ipv6_mtu(link, LOG_INFO);
753✔
731

732
        r = link_set_ipv6ll_stable_secret(link);
753✔
733
        if (r < 0)
753✔
734
                log_link_warning_errno(link, r, "Cannot set stable secret address for IPv6 link-local address: %m");
×
735

736
        r = link_set_ipv4_accept_local(link);
753✔
737
        if (r < 0)
753✔
738
                log_link_warning_errno(link, r, "Cannot set IPv4 accept_local flag for interface, ignoring: %m");
×
739

740
        r = link_set_ipv4_route_localnet(link);
753✔
741
        if (r < 0)
753✔
742
                log_link_warning_errno(link, r, "Cannot set IPv4 route_localnet flag for interface, ignoring: %m");
×
743

744
        r = link_set_ipv4_rp_filter(link);
753✔
745
        if (r < 0)
753✔
746
                log_link_warning_errno(link, r, "Cannot set IPv4 reverse path filtering for interface, ignoring: %m");
×
747

748
        r = link_set_ipv4_force_igmp_version(link);
753✔
749
        if (r < 0)
753✔
750
                log_link_warning_errno(link, r, "Cannot set IPv4 force igmp version, ignoring: %m");
×
751

752
        r = link_set_ipv4_promote_secondaries(link);
753✔
753
        if (r < 0)
753✔
754
                log_link_warning_errno(link, r, "Cannot enable promote_secondaries for interface, ignoring: %m");
1✔
755

756
        r = link_set_mpls_input(link);
753✔
757
        if (r < 0)
753✔
758
                log_link_warning_errno(link, r, "Cannot set MPLS input, ignoring: %m");
×
759

760
        return 0;
753✔
761
}
762

763
static const char* const ipv6_privacy_extensions_table[_IPV6_PRIVACY_EXTENSIONS_MAX] = {
764
        [IPV6_PRIVACY_EXTENSIONS_NO]            = "no",
765
        [IPV6_PRIVACY_EXTENSIONS_PREFER_PUBLIC] = "prefer-public",
766
        [IPV6_PRIVACY_EXTENSIONS_YES]           = "yes",
767
        [IPV6_PRIVACY_EXTENSIONS_KERNEL]        = "kernel",
768
};
769

770
DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(ipv6_privacy_extensions, IPv6PrivacyExtensions,
76✔
771
                                        IPV6_PRIVACY_EXTENSIONS_YES);
772
DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv6_privacy_extensions, ipv6_privacy_extensions, IPv6PrivacyExtensions);
22✔
773

774
static const char* const ip_reverse_path_filter_table[_IP_REVERSE_PATH_FILTER_MAX] = {
775
        [IP_REVERSE_PATH_FILTER_NO]     = "no",
776
        [IP_REVERSE_PATH_FILTER_STRICT] = "strict",
777
        [IP_REVERSE_PATH_FILTER_LOOSE]  = "loose",
778
};
779

780
DEFINE_STRING_TABLE_LOOKUP(ip_reverse_path_filter, IPReversePathFilter);
2✔
781
DEFINE_CONFIG_PARSE_ENUM(config_parse_ip_reverse_path_filter, ip_reverse_path_filter, IPReversePathFilter);
2✔
782

783
int config_parse_ip_forward_deprecated(
×
784
                const char* unit,
785
                const char *filename,
786
                unsigned line,
787
                const char *section,
788
                unsigned section_line,
789
                const char *lvalue,
790
                int ltype,
791
                const char *rvalue,
792
                void *data,
793
                void *userdata) {
794

795
        assert(filename);
×
796

797
        log_syntax(unit, LOG_WARNING, filename, line, 0,
×
798
                   "IPForward= setting is deprecated. "
799
                   "Please use IPv4Forwarding= and/or IPv6Forwarding= in networkd.conf for global setting, "
800
                   "and the same settings in .network files for per-interface setting.");
801
        return 0;
×
802
}
803

804
static const char* const ipv4_force_igmp_version_table[_IPV4_FORCE_IGMP_VERSION_MAX] = {
805
        [IPV4_FORCE_IGMP_VERSION_NO] = "no",
806
        [IPV4_FORCE_IGMP_VERSION_1]  = "v1",
807
        [IPV4_FORCE_IGMP_VERSION_2]  = "v2",
808
        [IPV4_FORCE_IGMP_VERSION_3]  = "v3",
809
};
810

811
DEFINE_STRING_TABLE_LOOKUP(ipv4_force_igmp_version, IPv4ForceIgmpVersion);
2✔
812
DEFINE_CONFIG_PARSE_ENUM(config_parse_ipv4_force_igmp_version, ipv4_force_igmp_version, IPv4ForceIgmpVersion);
2✔
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