summaryrefslogtreecommitdiffhomepage
path: root/system-linux.c
blob: 0e6ce5ac686570dc15de99b6f6b46c43225d6d4c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
#define _GNU_SOURCE

#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/syscall.h>

#include <net/if.h>
#include <net/if_arp.h>

#include <arpa/inet.h>
#include <netinet/in.h>

#include <linux/rtnetlink.h>
#include <linux/sockios.h>
#include <linux/ip.h>
#include <linux/if_vlan.h>
#include <linux/if_bridge.h>
#include <linux/if_tunnel.h>
#include <linux/ethtool.h>

#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <glob.h>
#include <time.h>

#include <netlink/msg.h>
#include <netlink/attr.h>
#include <netlink/socket.h>
#include <libubox/uloop.h>

#include "netifd.h"
#include "device.h"
#include "system.h"

struct event_socket {
	struct uloop_fd uloop;
	struct nl_sock *sock;
	struct nl_cb *cb;
};

static int sock_ioctl = -1;
static struct nl_sock *sock_rtnl = NULL;

static int cb_rtnl_event(struct nl_msg *msg, void *arg);
static void handle_hotplug_event(struct uloop_fd *u, unsigned int events);

static char dev_buf[256];

static void
handler_nl_event(struct uloop_fd *u, unsigned int events)
{
	struct event_socket *ev = container_of(u, struct event_socket, uloop);
	nl_recvmsgs(ev->sock, ev->cb);
}

static struct nl_sock *
create_socket(int protocol, int groups)
{
	struct nl_sock *sock;

	sock = nl_socket_alloc();
	if (!sock)
		return NULL;

	if (groups)
		nl_join_groups(sock, groups);

	if (nl_connect(sock, protocol))
		return NULL;

	return sock;
}

static bool
create_raw_event_socket(struct event_socket *ev, int protocol, int groups,
			uloop_fd_handler cb)
{
	ev->sock = create_socket(protocol, groups);
	if (!ev->sock)
		return false;

	ev->uloop.fd = nl_socket_get_fd(ev->sock);
	ev->uloop.cb = cb;
	uloop_fd_add(&ev->uloop, ULOOP_READ | ULOOP_EDGE_TRIGGER);
	return true;
}

static bool
create_event_socket(struct event_socket *ev, int protocol,
		    int (*cb)(struct nl_msg *msg, void *arg))
{
	// Prepare socket for link events
	ev->cb = nl_cb_alloc(NL_CB_DEFAULT);
	if (!ev->cb)
		return false;

	nl_cb_set(ev->cb, NL_CB_VALID, NL_CB_CUSTOM, cb, NULL);

	return create_raw_event_socket(ev, protocol, 0, handler_nl_event);
}

int system_init(void)
{
	static struct event_socket rtnl_event;
	static struct event_socket hotplug_event;

	sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0);
	fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC);

	// Prepare socket for routing / address control
	sock_rtnl = create_socket(NETLINK_ROUTE, 0);
	if (!sock_rtnl)
		return -1;

	if (!create_event_socket(&rtnl_event, NETLINK_ROUTE, cb_rtnl_event))
		return -1;

	if (!create_raw_event_socket(&hotplug_event, NETLINK_KOBJECT_UEVENT, 1,
				     handle_hotplug_event))
		return -1;

	// Receive network link events form kernel
	nl_socket_add_membership(rtnl_event.sock, RTNLGRP_LINK);

	return 0;
}

static void system_set_sysctl(const char *path, const char *val)
{
	int fd;

	fd = open(path, O_WRONLY);
	if (fd < 0)
		return;

	write(fd, val, strlen(val));
	close(fd);
}

static void system_set_dev_sysctl(const char *path, const char *device, const char *val)
{
	snprintf(dev_buf, sizeof(dev_buf), path, val);
	system_set_sysctl(dev_buf, val);
}

static void system_set_disable_ipv6(struct device *dev, const char *val)
{
	system_set_dev_sysctl("/proc/sys/net/ipv6/conf/%s/disable_ipv6", dev->ifname, val);
}

// Evaluate netlink messages
static int cb_rtnl_event(struct nl_msg *msg, void *arg)
{
	struct nlmsghdr *nh = nlmsg_hdr(msg);
	struct ifinfomsg *ifi = NLMSG_DATA(nh);
	struct nlattr *nla[__IFLA_MAX];

	if (nh->nlmsg_type != RTM_DELLINK && nh->nlmsg_type != RTM_NEWLINK)
		goto out;

	nlmsg_parse(nh, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL);
	if (!nla[IFLA_IFNAME])
		goto out;

	struct device *dev = device_get(RTA_DATA(nla[IFLA_IFNAME]), false);
	if (!dev)
		goto out;

	dev->ifindex = ifi->ifi_index;
	/* TODO: parse link status */

out:
	return 0;
}

static void
handle_hotplug_msg(char *data, int size)
{
	const char *subsystem = NULL, *interface = NULL;
	char *cur, *end, *sep;
	struct device *dev;
	int skip;
	bool add;

	if (!strncmp(data, "add@", 4))
		add = true;
	else if (!strncmp(data, "remove@", 7))
		add = false;
	else
		return;

	skip = strlen(data) + 1;
	end = data + size;

	for (cur = data + skip; cur < end; cur += skip) {
		skip = strlen(cur) + 1;

		sep = strchr(cur, '=');
		if (!sep)
			continue;

		*sep = 0;
		if (!strcmp(cur, "INTERFACE"))
			interface = sep + 1;
		else if (!strcmp(cur, "SUBSYSTEM")) {
			subsystem = sep + 1;
			if (strcmp(subsystem, "net") != 0)
				return;
		}
		if (subsystem && interface)
			goto found;
	}
	return;

found:
	dev = device_get(interface, false);
	if (!dev)
		return;

	if (dev->type != &simple_device_type)
		return;

	device_set_present(dev, add);
}

static void
handle_hotplug_event(struct uloop_fd *u, unsigned int events)
{
	struct event_socket *ev = container_of(u, struct event_socket, uloop);
	struct sockaddr_nl nla;
	unsigned char *buf = NULL;
	int size;

	while ((size = nl_recv(ev->sock, &nla, &buf, NULL)) > 0) {
		if (nla.nl_pid == 0)
			handle_hotplug_msg((char *) buf, size);

		free(buf);
	}
}

static int system_rtnl_call(struct nl_msg *msg)
{
	int s = -(nl_send_auto_complete(sock_rtnl, msg)
			|| nl_wait_for_ack(sock_rtnl));
	nlmsg_free(msg);
	return s;
}

int system_bridge_delbr(struct device *bridge)
{
	return ioctl(sock_ioctl, SIOCBRDELBR, bridge->ifname);
}

static int system_bridge_if(const char *bridge, struct device *dev, int cmd, void *data)
{
	struct ifreq ifr;
	if (dev)
		ifr.ifr_ifindex = dev->ifindex;
	else
		ifr.ifr_data = data;
	strncpy(ifr.ifr_name, bridge, sizeof(ifr.ifr_name));
	return ioctl(sock_ioctl, cmd, &ifr);
}

static bool system_is_bridge(const char *name, char *buf, int buflen)
{
	struct stat st;

	snprintf(buf, buflen, "/sys/devices/virtual/net/%s/bridge", name);
	if (stat(buf, &st) < 0)
		return false;

	return true;
}

static char *system_get_bridge(const char *name, char *buf, int buflen)
{
	char *path;
	ssize_t len;
	glob_t gl;

	snprintf(buf, buflen, "/sys/devices/virtual/net/*/brif/%s/bridge", name);
	if (glob(buf, GLOB_NOSORT, NULL, &gl) < 0)
		return NULL;

	if (gl.gl_pathc == 0)
		return NULL;

	len = readlink(gl.gl_pathv[0], buf, buflen);
	if (len < 0)
		return NULL;

	buf[len] = 0;
	path = strrchr(buf, '/');
	if (!path)
		return NULL;

	return path + 1;
}

int system_bridge_addif(struct device *bridge, struct device *dev)
{
	char *oldbr;

	system_set_disable_ipv6(dev, "1");
	oldbr = system_get_bridge(dev->ifname, dev_buf, sizeof(dev_buf));
	if (oldbr && !strcmp(oldbr, bridge->ifname))
		return 0;

	return system_bridge_if(bridge->ifname, dev, SIOCBRADDIF, NULL);
}

int system_bridge_delif(struct device *bridge, struct device *dev)
{
	system_set_disable_ipv6(dev, "0");
	return system_bridge_if(bridge->ifname, dev, SIOCBRDELIF, NULL);
}

static int system_if_resolve(struct device *dev)
{
	struct ifreq ifr;
	strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
	if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
		return ifr.ifr_ifindex;
	else
		return 0;
}

static int system_if_flags(const char *ifname, unsigned add, unsigned rem)
{
	struct ifreq ifr;
	strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
	ioctl(sock_ioctl, SIOCGIFFLAGS, &ifr);
	ifr.ifr_flags |= add;
	ifr.ifr_flags &= ~rem;
	return ioctl(sock_ioctl, SIOCSIFFLAGS, &ifr);
}

struct clear_data {
	struct nl_msg *msg;
	struct device *dev;
	int type;
	int size;
	int af;
};


static bool check_ifaddr(struct nlmsghdr *hdr, int ifindex)
{
	struct ifaddrmsg *ifa = NLMSG_DATA(hdr);

	return ifa->ifa_index == ifindex;
}

static bool check_route(struct nlmsghdr *hdr, int ifindex)
{
	struct nlattr *tb[__RTA_MAX];

	nlmsg_parse(hdr, sizeof(struct rtmsg), tb, __RTA_MAX - 1, NULL);
	if (!tb[RTA_OIF])
		return false;

	return *(int *)RTA_DATA(tb[RTA_OIF]) == ifindex;
}

static int cb_clear_event(struct nl_msg *msg, void *arg)
{
	struct clear_data *clr = arg;
	struct nlmsghdr *hdr = nlmsg_hdr(msg);
	bool (*cb)(struct nlmsghdr *, int ifindex);
	int type;

	switch(clr->type) {
	case RTM_GETADDR:
		type = RTM_DELADDR;
		if (hdr->nlmsg_type != RTM_NEWADDR)
			return NL_SKIP;

		cb = check_ifaddr;
		break;
	case RTM_GETROUTE:
		type = RTM_DELROUTE;
		if (hdr->nlmsg_type != RTM_NEWROUTE)
			return NL_SKIP;

		cb = check_route;
		break;
	default:
		return NL_SKIP;
	}

	if (!cb(hdr, clr->dev->ifindex))
		return NL_SKIP;

	D(SYSTEM, "Remove %s from device %s\n",
	  type == RTM_DELADDR ? "an address" : "a route",
	  clr->dev->ifname);
	memcpy(nlmsg_hdr(clr->msg), hdr, hdr->nlmsg_len);
	hdr = nlmsg_hdr(clr->msg);
	hdr->nlmsg_type = type;
	hdr->nlmsg_flags = NLM_F_REQUEST;

	if (!nl_send_auto_complete(sock_rtnl, clr->msg))
		nl_wait_for_ack(sock_rtnl);

	return NL_SKIP;
}

static int
cb_finish_event(struct nl_msg *msg, void *arg)
{
	int *pending = arg;
	*pending = 0;
	return NL_STOP;
}

static int
error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg)
{
	int *pending = arg;
	*pending = err->error;
	return NL_STOP;
}

static void
system_if_clear_entries(struct device *dev, int type, int af)
{
	struct clear_data clr;
	struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT);
	struct rtmsg rtm = {
		.rtm_family = af,
		.rtm_flags = RTM_F_CLONED,
	};
	int flags = NLM_F_DUMP;
	int pending = 1;

	clr.af = af;
	clr.dev = dev;
	clr.type = type;
	switch (type) {
	case RTM_GETADDR:
		clr.size = sizeof(struct rtgenmsg);
		break;
	case RTM_GETROUTE:
		clr.size = sizeof(struct rtmsg);
		break;
	default:
		return;
	}

	if (!cb)
		return;

	clr.msg = nlmsg_alloc_simple(type, flags);
	if (!clr.msg)
		goto out;

	nlmsg_append(clr.msg, &rtm, clr.size, 0);
	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_clear_event, &clr);
	nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, cb_finish_event, &pending);
	nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &pending);

	nl_send_auto_complete(sock_rtnl, clr.msg);
	while (pending > 0)
		nl_recvmsgs(sock_rtnl, cb);

	nlmsg_free(clr.msg);
out:
	nl_cb_put(cb);
}

/*
 * Clear bridge (membership) state and bring down device
 */
void system_if_clear_state(struct device *dev)
{
	static char buf[256];
	char *bridge;

	if (dev->external)
		return;

	dev->ifindex = system_if_resolve(dev);
	if (!dev->ifindex)
		return;

	system_if_flags(dev->ifname, 0, IFF_UP);

	if (system_is_bridge(dev->ifname, buf, sizeof(buf))) {
		D(SYSTEM, "Delete existing bridge named '%s'\n", dev->ifname);
		system_bridge_delbr(dev);
		return;
	}

	bridge = system_get_bridge(dev->ifname, buf, sizeof(buf));
	if (bridge) {
		D(SYSTEM, "Remove device '%s' from bridge '%s'\n", dev->ifname, bridge);
		system_bridge_if(bridge, dev, SIOCBRDELIF, NULL);
	}

	system_if_clear_entries(dev, RTM_GETROUTE, AF_INET);
	system_if_clear_entries(dev, RTM_GETADDR, AF_INET);
	system_if_clear_entries(dev, RTM_GETROUTE, AF_INET6);
	system_if_clear_entries(dev, RTM_GETADDR, AF_INET6);
	system_set_disable_ipv6(dev, "0");
}

static inline unsigned long
sec_to_jiffies(int val)
{
	return (unsigned long) val * 100;
}

int system_bridge_addbr(struct device *bridge, struct bridge_config *cfg)
{
	unsigned long args[4] = {};

	if (ioctl(sock_ioctl, SIOCBRADDBR, bridge->ifname) < 0)
		return -1;

	args[0] = BRCTL_SET_BRIDGE_STP_STATE;
	args[1] = !!cfg->stp;
	system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);

	args[0] = BRCTL_SET_BRIDGE_FORWARD_DELAY;
	args[1] = sec_to_jiffies(cfg->forward_delay);
	system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);

	system_set_dev_sysctl("/sys/devices/virtual/net/%s/bridge/multicast_snooping",
		bridge->ifname, cfg->igmp_snoop ? "1" : "0");

	if (cfg->flags & BRIDGE_OPT_AGEING_TIME) {
		args[0] = BRCTL_SET_AGEING_TIME;
		args[1] = sec_to_jiffies(cfg->ageing_time);
		system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
	}

	if (cfg->flags & BRIDGE_OPT_HELLO_TIME) {
		args[0] = BRCTL_SET_BRIDGE_HELLO_TIME;
		args[1] = sec_to_jiffies(cfg->hello_time);
		system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
	}

	if (cfg->flags & BRIDGE_OPT_MAX_AGE) {
		args[0] = BRCTL_SET_BRIDGE_MAX_AGE;
		args[1] = sec_to_jiffies(cfg->max_age);
		system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
	}

	return 0;
}

static int system_vlan(struct device *dev, int id)
{
	struct vlan_ioctl_args ifr = {
		.cmd = SET_VLAN_NAME_TYPE_CMD,
		.u.name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD,
	};

	ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);

	if (id < 0) {
		ifr.cmd = DEL_VLAN_CMD;
		ifr.u.VID = 0;
	} else {
		ifr.cmd = ADD_VLAN_CMD;
		ifr.u.VID = id;
	}
	strncpy(ifr.device1, dev->ifname, sizeof(ifr.device1));
	return ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
}

int system_vlan_add(struct device *dev, int id)
{
	return system_vlan(dev, id);
}

int system_vlan_del(struct device *dev)
{
	return system_vlan(dev, -1);
}

static void
system_if_get_settings(struct device *dev, struct device_settings *s)
{
	struct ifreq ifr;

	memset(&ifr, 0, sizeof(ifr));
	strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));

	if (ioctl(sock_ioctl, SIOCGIFMTU, &ifr) == 0) {
		s->mtu = ifr.ifr_mtu;
		s->flags |= DEV_OPT_MTU;
	}

	if (ioctl(sock_ioctl, SIOCGIFTXQLEN, &ifr) == 0) {
		s->txqueuelen = ifr.ifr_qlen;
		s->flags |= DEV_OPT_TXQUEUELEN;
	}

	if (ioctl(sock_ioctl, SIOCGIFHWADDR, &ifr) == 0) {
		memcpy(s->macaddr, &ifr.ifr_hwaddr.sa_data, sizeof(s->macaddr));
		s->flags |= DEV_OPT_MACADDR;
	}
}

static void
system_if_apply_settings(struct device *dev, struct device_settings *s)
{
	struct ifreq ifr;

	memset(&ifr, 0, sizeof(ifr));
	strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
	if (s->flags & DEV_OPT_MTU) {
		ifr.ifr_mtu = s->mtu;
		if (ioctl(sock_ioctl, SIOCSIFMTU, &ifr) < 0)
			s->flags &= ~DEV_OPT_MTU;
	}
	if (s->flags & DEV_OPT_TXQUEUELEN) {
		ifr.ifr_qlen = s->txqueuelen;
		if (ioctl(sock_ioctl, SIOCSIFTXQLEN, &ifr) < 0)
			s->flags &= ~DEV_OPT_TXQUEUELEN;
	}
	if (s->flags & DEV_OPT_MACADDR) {
		ifr.ifr_hwaddr.sa_family = ARPHRD_ETHER;
		memcpy(&ifr.ifr_hwaddr.sa_data, s->macaddr, sizeof(s->macaddr));
		if (ioctl(sock_ioctl, SIOCSIFHWADDR, &ifr) < 0)
			s->flags &= ~DEV_OPT_MACADDR;
	}
}

int system_if_up(struct device *dev)
{
	system_if_get_settings(dev, &dev->orig_settings);
	system_if_apply_settings(dev, &dev->settings);
	dev->ifindex = system_if_resolve(dev);
	return system_if_flags(dev->ifname, IFF_UP, 0);
}

int system_if_down(struct device *dev)
{
	int ret = system_if_flags(dev->ifname, 0, IFF_UP);
	dev->orig_settings.flags &= dev->settings.flags;
	system_if_apply_settings(dev, &dev->orig_settings);
	return ret;
}

int system_if_check(struct device *dev)
{
	device_set_present(dev, (system_if_resolve(dev) > 0));
	return 0;
}

struct device *
system_if_get_parent(struct device *dev)
{
	char buf[64], *devname;
	int ifindex, iflink, len;
	FILE *f;

	snprintf(buf, sizeof(buf), "/sys/class/net/%s/iflink", dev->ifname);
	f = fopen(buf, "r");
	if (!f)
		return NULL;

	len = fread(buf, 1, sizeof(buf) - 1, f);
	fclose(f);

	if (len <= 0)
		return NULL;

	buf[len] = 0;
	iflink = strtoul(buf, NULL, 0);
	ifindex = system_if_resolve(dev);
	if (!iflink || iflink == ifindex)
		return NULL;

	devname = if_indextoname(iflink, buf);
	if (!devname)
		return NULL;

	return device_get(devname, true);
}

static bool
read_string_file(int dir_fd, const char *file, char *buf, int len)
{
	bool ret = false;
	char *c;
	int fd;

	fd = openat(dir_fd, file, O_RDONLY);
	if (fd < 0)
		return false;

retry:
	len = read(fd, buf, len - 1);
	if (len < 0) {
		if (errno == EINTR)
			goto retry;
	} else if (len > 0) {
			buf[len] = 0;

			c = strchr(buf, '\n');
			if (c)
				*c = 0;

			ret = true;
	}

	close(fd);

	return ret;
}

static bool
read_int_file(int dir_fd, const char *file, int *val)
{
	char buf[64];
	bool ret = false;

	ret = read_string_file(dir_fd, file, buf, sizeof(buf));
	if (ret)
		*val = strtoul(buf, NULL, 0);

	return ret;
}

/* Assume advertised flags == supported flags */
static const struct {
	uint32_t mask;
	const char *name;
} ethtool_link_modes[] = {
	{ ADVERTISED_10baseT_Half, "10H" },
	{ ADVERTISED_10baseT_Full, "10F" },
	{ ADVERTISED_100baseT_Half, "100H" },
	{ ADVERTISED_100baseT_Full, "100F" },
	{ ADVERTISED_1000baseT_Half, "1000H" },
	{ ADVERTISED_1000baseT_Full, "1000F" },
};

static void system_add_link_modes(struct blob_buf *b, __u32 mask)
{
	int i;
	for (i = 0; i < ARRAY_SIZE(ethtool_link_modes); i++) {
		if (mask & ethtool_link_modes[i].mask)
			blobmsg_add_string(b, NULL, ethtool_link_modes[i].name);
	}
}

int
system_if_dump_info(struct device *dev, struct blob_buf *b)
{
	struct ethtool_cmd ecmd;
	struct ifreq ifr;
	char buf[64], *s;
	void *c;
	int dir_fd, val = 0;

	snprintf(buf, sizeof(buf), "/sys/class/net/%s", dev->ifname);
	dir_fd = open(buf, O_DIRECTORY);

	if (read_int_file(dir_fd, "carrier", &val))
		blobmsg_add_u8(b, "link", !!val);

	memset(&ecmd, 0, sizeof(ecmd));
	memset(&ifr, 0, sizeof(ifr));
	strcpy(ifr.ifr_name, dev->ifname);
	ifr.ifr_data = (caddr_t) &ecmd;
	ecmd.cmd = ETHTOOL_GSET;

	if (ioctl(sock_ioctl, SIOCETHTOOL, &ifr) == 0) {
		c = blobmsg_open_array(b, "link-advertising");
		system_add_link_modes(b, ecmd.advertising);
		blobmsg_close_array(b, c);

		c = blobmsg_open_array(b, "link-supported");
		system_add_link_modes(b, ecmd.supported);
		blobmsg_close_array(b, c);

		s = blobmsg_alloc_string_buffer(b, "speed", 8);
		snprintf(s, 8, "%d%c", ethtool_cmd_speed(&ecmd),
			ecmd.duplex == DUPLEX_HALF ? 'H' : 'F');
		blobmsg_add_string_buffer(b);
	}

	close(dir_fd);
	return 0;
}

int
system_if_dump_stats(struct device *dev, struct blob_buf *b)
{
	const char *const counters[] = {
		"collisions",     "rx_frame_errors",   "tx_compressed",
		"multicast",      "rx_length_errors",  "tx_dropped",
		"rx_bytes",       "rx_missed_errors",  "tx_errors",
		"rx_compressed",  "rx_over_errors",    "tx_fifo_errors",
		"rx_crc_errors",  "rx_packets",        "tx_heartbeat_errors",
		"rx_dropped",     "tx_aborted_errors", "tx_packets",
		"rx_errors",      "tx_bytes",          "tx_window_errors",
		"rx_fifo_errors", "tx_carrier_errors",
	};
	char buf[64];
	int stats_dir;
	int i, val = 0;

	snprintf(buf, sizeof(buf), "/sys/class/net/%s/statistics", dev->ifname);
	stats_dir = open(buf, O_DIRECTORY);
	if (stats_dir < 0)
		return -1;

	for (i = 0; i < ARRAY_SIZE(counters); i++)
		if (read_int_file(stats_dir, counters[i], &val))
			blobmsg_add_u32(b, counters[i], val);

	close(stats_dir);
	return 0;
}

static int system_addr(struct device *dev, struct device_addr *addr, int cmd)
{
	bool v4 = ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET4);
	int alen = v4 ? 4 : 16;
	struct ifaddrmsg ifa = {
		.ifa_family = (alen == 4) ? AF_INET : AF_INET6,
		.ifa_prefixlen = addr->mask,
		.ifa_index = dev->ifindex,
	};

	struct nl_msg *msg;

	msg = nlmsg_alloc_simple(cmd, 0);
	if (!msg)
		return -1;

	nlmsg_append(msg, &ifa, sizeof(ifa), 0);
	nla_put(msg, IFA_LOCAL, alen, &addr->addr);
	if (v4)
		nla_put_u32(msg, IFA_BROADCAST, addr->broadcast);

	return system_rtnl_call(msg);
}

int system_add_address(struct device *dev, struct device_addr *addr)
{
	return system_addr(dev, addr, RTM_NEWADDR);
}

int system_del_address(struct device *dev, struct device_addr *addr)
{
	return system_addr(dev, addr, RTM_DELADDR);
}

static int system_rt(struct device *dev, struct device_route *route, int cmd)
{
	int alen = ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
	bool have_gw;
	unsigned int flags = 0;
	int ifindex = dev->ifindex;

	if (alen == 4)
		have_gw = !!route->nexthop.in.s_addr;
	else
		have_gw = route->nexthop.in6.s6_addr32[0] ||
			route->nexthop.in6.s6_addr32[1] ||
			route->nexthop.in6.s6_addr32[2] ||
			route->nexthop.in6.s6_addr32[3];

	unsigned char scope = (cmd == RTM_DELROUTE) ? RT_SCOPE_NOWHERE :
			(have_gw) ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK;

	struct rtmsg rtm = {
		.rtm_family = (alen == 4) ? AF_INET : AF_INET6,
		.rtm_dst_len = route->mask,
		.rtm_table = RT_TABLE_MAIN,
		.rtm_protocol = RTPROT_BOOT,
		.rtm_scope = scope,
		.rtm_type = (cmd == RTM_DELROUTE) ? 0: RTN_UNICAST,
	};
	struct nl_msg *msg;

	if (cmd == RTM_NEWROUTE)
		flags |= NLM_F_CREATE | NLM_F_REPLACE;

	msg = nlmsg_alloc_simple(cmd, flags);
	if (!msg)
		return -1;

	nlmsg_append(msg, &rtm, sizeof(rtm), 0);

	if (route->mask)
		nla_put(msg, RTA_DST, alen, &route->addr);

	if (route->metric > 0)
		nla_put_u32(msg, RTA_PRIORITY, route->metric);

	if (have_gw)
		nla_put(msg, RTA_GATEWAY, alen, &route->nexthop);

	if (route->flags & DEVADDR_DEVICE)
		nla_put_u32(msg, RTA_OIF, ifindex);

	return system_rtnl_call(msg);
}

int system_add_route(struct device *dev, struct device_route *route)
{
	return system_rt(dev, route, RTM_NEWROUTE);
}

int system_del_route(struct device *dev, struct device_route *route)
{
	return system_rt(dev, route, RTM_DELROUTE);
}

int system_flush_routes(void)
{
	const char *names[] = {
		"/proc/sys/net/ipv4/route/flush",
		"/proc/sys/net/ipv6/route/flush"
	};
	int fd, i;

	for (i = 0; i < ARRAY_SIZE(names); i++) {
		fd = open(names[i], O_WRONLY);
		if (fd < 0)
			continue;

		write(fd, "-1", 2);
		close(fd);
	}
	return 0;
}

time_t system_get_rtime(void)
{
	struct timespec ts;
	struct timeval tv;

	if (syscall(__NR_clock_gettime, CLOCK_MONOTONIC, &ts) == 0)
		return ts.tv_sec;

	if (gettimeofday(&tv, NULL) == 0)
		return tv.tv_sec;

	return 0;
}

#ifndef IP_DF
#define IP_DF       0x4000
#endif

static void tunnel_parm_init(struct ip_tunnel_parm *p)
{
	memset(p, 0, sizeof(*p));
	p->iph.version = 4;
	p->iph.ihl = 5;
	p->iph.frag_off = htons(IP_DF);
}

static int tunnel_ioctl(const char *name, int cmd, void *p)
{
	struct ifreq ifr;

	memset(&ifr, 0, sizeof(ifr));
	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
	ifr.ifr_ifru.ifru_data = p;
	return ioctl(sock_ioctl, cmd, &ifr);
}

int system_del_ip_tunnel(const char *name)
{
	struct ip_tunnel_parm p;

	tunnel_parm_init(&p);
	return tunnel_ioctl(name, SIOCDELTUNNEL, &p);
}

static int parse_ipaddr(struct blob_attr *attr, __be32 *addr)
{
	if (!attr)
		return 1;

	return inet_pton(AF_INET, blobmsg_data(attr), (void *) addr);
}


int system_add_ip_tunnel(const char *name, struct blob_attr *attr)
{
	struct blob_attr *tb[__TUNNEL_ATTR_MAX];
	struct blob_attr *cur;
	struct ip_tunnel_parm p;
	const char *base, *str;
	int cmd = SIOCADDTUNNEL;

	system_del_ip_tunnel(name);

	tunnel_parm_init(&p);

	blobmsg_parse(tunnel_attr_list.params, __TUNNEL_ATTR_MAX, tb,
		blob_data(attr), blob_len(attr));

	cur = tb[TUNNEL_ATTR_TYPE];
	if (!cur)
		return -EINVAL;

	str = blobmsg_data(cur);
	if (!strcmp(str, "sit")) {
		p.iph.protocol = IPPROTO_IPV6;
		base = "sit0";
	} else
		return -EINVAL;

	if (!parse_ipaddr(tb[TUNNEL_ATTR_LOCAL], &p.iph.saddr))
		return -EINVAL;

	if (!parse_ipaddr(tb[TUNNEL_ATTR_REMOTE], &p.iph.daddr))
		return -EINVAL;

	if ((cur = tb[TUNNEL_ATTR_TTL])) {
		unsigned int val = blobmsg_get_u32(cur);

		if (val > 255)
			return -EINVAL;

		p.iph.ttl = val;
	}

	strncpy(p.name, name, sizeof(p.name));
	return tunnel_ioctl(base, cmd, &p);
}