rework route handling, move parser code to interface-ip.c, add extra options and...
[project/netifd.git] / system-linux.c
1 #define _GNU_SOURCE
2
3 #include <sys/socket.h>
4 #include <sys/ioctl.h>
5 #include <sys/stat.h>
6 #include <sys/syscall.h>
7
8 #include <linux/rtnetlink.h>
9 #include <linux/sockios.h>
10 #include <linux/if_vlan.h>
11 #include <linux/if_bridge.h>
12
13 #include <unistd.h>
14 #include <string.h>
15 #include <fcntl.h>
16 #include <glob.h>
17
18 #include <netlink/msg.h>
19 #include <netlink/attr.h>
20 #include <netlink/socket.h>
21 #include <libubox/uloop.h>
22
23 #include "netifd.h"
24 #include "device.h"
25 #include "system.h"
26
27 static int sock_ioctl = -1;
28 static struct nl_sock *sock_rtnl = NULL;
29 static struct nl_sock *sock_rtnl_event = NULL;
30
31 static void handler_rtnl_event(struct uloop_fd *u, unsigned int events);
32 static int cb_rtnl_event(struct nl_msg *msg, void *arg);
33 static struct uloop_fd rtnl_event = {.cb = handler_rtnl_event};
34 static struct nl_cb *nl_cb_rtnl_event;
35
36 int system_init(void)
37 {
38 sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0);
39 fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC);
40
41 // Prepare socket for routing / address control
42 sock_rtnl = nl_socket_alloc();
43 if (!sock_rtnl)
44 return -1;
45
46 if (nl_connect(sock_rtnl, NETLINK_ROUTE))
47 goto error_free_sock;
48
49 // Prepare socket for link events
50 nl_cb_rtnl_event = nl_cb_alloc(NL_CB_DEFAULT);
51 if (!nl_cb_rtnl_event)
52 goto error_free_sock;
53
54 nl_cb_set(nl_cb_rtnl_event, NL_CB_VALID, NL_CB_CUSTOM,
55 cb_rtnl_event, NULL);
56
57 sock_rtnl_event = nl_socket_alloc();
58 if (!sock_rtnl_event)
59 goto error_free_cb;
60
61 if (nl_connect(sock_rtnl_event, NETLINK_ROUTE))
62 goto error_free_event;
63
64 // Receive network link events form kernel
65 nl_socket_add_membership(sock_rtnl_event, RTNLGRP_LINK);
66
67 rtnl_event.fd = nl_socket_get_fd(sock_rtnl_event);
68 uloop_fd_add(&rtnl_event, ULOOP_READ | ULOOP_EDGE_TRIGGER);
69
70 return 0;
71
72 error_free_event:
73 nl_socket_free(sock_rtnl_event);
74 sock_rtnl_event = NULL;
75 error_free_cb:
76 nl_cb_put(nl_cb_rtnl_event);
77 nl_cb_rtnl_event = NULL;
78 error_free_sock:
79 nl_socket_free(sock_rtnl);
80 sock_rtnl = NULL;
81 return -1;
82 }
83
84 // If socket is ready for reading parse netlink events
85 static void handler_rtnl_event(struct uloop_fd *u, unsigned int events)
86 {
87 nl_recvmsgs(sock_rtnl_event, nl_cb_rtnl_event);
88 }
89
90 static void system_set_sysctl(const char *path, const char *val)
91 {
92 int fd;
93
94 fd = open(path, O_WRONLY);
95 if (fd < 0)
96 return;
97
98 write(fd, val, strlen(val));
99 close(fd);
100 }
101
102 static void system_set_dev_sysctl(const char *path, const char *device, const char *val)
103 {
104 char buf[256];
105
106 snprintf(buf, sizeof(buf), path, val);
107 system_set_sysctl(buf, val);
108 }
109
110 static void system_set_disable_ipv6(struct device *dev, const char *val)
111 {
112 system_set_dev_sysctl("/proc/sys/net/ipv6/conf/%s/disable_ipv6", dev->ifname, val);
113 }
114
115 // Evaluate netlink messages
116 static int cb_rtnl_event(struct nl_msg *msg, void *arg)
117 {
118 struct nlmsghdr *nh = nlmsg_hdr(msg);
119 struct ifinfomsg *ifi = NLMSG_DATA(nh);
120 struct nlattr *nla[__IFLA_MAX];
121
122 if (nh->nlmsg_type != RTM_DELLINK && nh->nlmsg_type != RTM_NEWLINK)
123 goto out;
124
125 nlmsg_parse(nh, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL);
126 if (!nla[IFLA_IFNAME])
127 goto out;
128
129 struct device *dev = device_get(RTA_DATA(nla[IFLA_IFNAME]), false);
130 if (!dev)
131 goto out;
132
133 dev->ifindex = ifi->ifi_index;
134 device_set_present(dev, (nh->nlmsg_type == RTM_NEWLINK));
135
136 out:
137 return 0;
138 }
139
140 static int system_rtnl_call(struct nl_msg *msg)
141 {
142 int s = -(nl_send_auto_complete(sock_rtnl, msg)
143 || nl_wait_for_ack(sock_rtnl));
144 nlmsg_free(msg);
145 return s;
146 }
147
148 int system_bridge_delbr(struct device *bridge)
149 {
150 return ioctl(sock_ioctl, SIOCBRDELBR, bridge->ifname);
151 }
152
153 static int system_bridge_if(const char *bridge, struct device *dev, int cmd, void *data)
154 {
155 struct ifreq ifr;
156 if (dev)
157 ifr.ifr_ifindex = dev->ifindex;
158 else
159 ifr.ifr_data = data;
160 strncpy(ifr.ifr_name, bridge, sizeof(ifr.ifr_name));
161 return ioctl(sock_ioctl, cmd, &ifr);
162 }
163
164 int system_bridge_addif(struct device *bridge, struct device *dev)
165 {
166 system_set_disable_ipv6(dev, "1");
167 return system_bridge_if(bridge->ifname, dev, SIOCBRADDIF, NULL);
168 }
169
170 int system_bridge_delif(struct device *bridge, struct device *dev)
171 {
172 system_set_disable_ipv6(dev, "0");
173 return system_bridge_if(bridge->ifname, dev, SIOCBRDELIF, NULL);
174 }
175
176 static bool system_is_bridge(const char *name, char *buf, int buflen)
177 {
178 struct stat st;
179
180 snprintf(buf, buflen, "/sys/devices/virtual/net/%s/bridge", name);
181 if (stat(buf, &st) < 0)
182 return false;
183
184 return true;
185 }
186
187 static char *system_get_bridge(const char *name, char *buf, int buflen)
188 {
189 char *path;
190 ssize_t len;
191 glob_t gl;
192
193 snprintf(buf, buflen, "/sys/devices/virtual/net/*/brif/%s/bridge", name);
194 if (glob(buf, GLOB_NOSORT, NULL, &gl) < 0)
195 return NULL;
196
197 if (gl.gl_pathc == 0)
198 return NULL;
199
200 len = readlink(gl.gl_pathv[0], buf, buflen);
201 if (len < 0)
202 return NULL;
203
204 buf[len] = 0;
205 path = strrchr(buf, '/');
206 if (!path)
207 return NULL;
208
209 return path + 1;
210 }
211
212 static int system_if_resolve(struct device *dev)
213 {
214 struct ifreq ifr;
215 strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
216 if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
217 return ifr.ifr_ifindex;
218 else
219 return 0;
220 }
221
222 static int system_if_flags(const char *ifname, unsigned add, unsigned rem)
223 {
224 struct ifreq ifr;
225 strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
226 ioctl(sock_ioctl, SIOCGIFFLAGS, &ifr);
227 ifr.ifr_flags |= add;
228 ifr.ifr_flags &= ~rem;
229 return ioctl(sock_ioctl, SIOCSIFFLAGS, &ifr);
230 }
231
232 struct clear_data {
233 struct nl_msg *msg;
234 struct device *dev;
235 int type;
236 int size;
237 int af;
238 };
239
240
241 static bool check_ifaddr(struct nlmsghdr *hdr, int ifindex)
242 {
243 struct ifaddrmsg *ifa = NLMSG_DATA(hdr);
244
245 return ifa->ifa_index == ifindex;
246 }
247
248 static bool check_route(struct nlmsghdr *hdr, int ifindex)
249 {
250 struct nlattr *tb[__RTA_MAX];
251
252 nlmsg_parse(hdr, sizeof(struct rtmsg), tb, __RTA_MAX - 1, NULL);
253 if (!tb[RTA_OIF])
254 return false;
255
256 return *(int *)RTA_DATA(tb[RTA_OIF]) == ifindex;
257 }
258
259 static int cb_clear_event(struct nl_msg *msg, void *arg)
260 {
261 struct clear_data *clr = arg;
262 struct nlmsghdr *hdr = nlmsg_hdr(msg);
263 bool (*cb)(struct nlmsghdr *, int ifindex);
264 int type;
265
266 switch(clr->type) {
267 case RTM_GETADDR:
268 type = RTM_DELADDR;
269 if (hdr->nlmsg_type != RTM_NEWADDR)
270 return NL_SKIP;
271
272 cb = check_ifaddr;
273 break;
274 case RTM_GETROUTE:
275 type = RTM_DELROUTE;
276 if (hdr->nlmsg_type != RTM_NEWROUTE)
277 return NL_SKIP;
278
279 cb = check_route;
280 break;
281 default:
282 return NL_SKIP;
283 }
284
285 if (!cb(hdr, clr->dev->ifindex))
286 return NL_SKIP;
287
288 D(SYSTEM, "Remove %s from device %s\n",
289 type == RTM_DELADDR ? "an address" : "a route",
290 clr->dev->ifname);
291 memcpy(nlmsg_hdr(clr->msg), hdr, hdr->nlmsg_len);
292 hdr = nlmsg_hdr(clr->msg);
293 hdr->nlmsg_type = type;
294 hdr->nlmsg_flags = NLM_F_REQUEST;
295
296 if (!nl_send_auto_complete(sock_rtnl, clr->msg))
297 nl_wait_for_ack(sock_rtnl);
298
299 return NL_SKIP;
300 }
301
302 static int
303 cb_finish_event(struct nl_msg *msg, void *arg)
304 {
305 int *pending = arg;
306 *pending = 0;
307 return NL_STOP;
308 }
309
310 static int
311 error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg)
312 {
313 int *pending = arg;
314 *pending = err->error;
315 return NL_STOP;
316 }
317
318 static void
319 system_if_clear_entries(struct device *dev, int type, int af)
320 {
321 struct clear_data clr;
322 struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT);
323 struct rtmsg rtm = {
324 .rtm_family = af,
325 .rtm_flags = RTM_F_CLONED,
326 };
327 int flags = NLM_F_DUMP;
328 int pending = 1;
329
330 clr.af = af;
331 clr.dev = dev;
332 clr.type = type;
333 switch (type) {
334 case RTM_GETADDR:
335 clr.size = sizeof(struct rtgenmsg);
336 break;
337 case RTM_GETROUTE:
338 clr.size = sizeof(struct rtmsg);
339 break;
340 default:
341 return;
342 }
343
344 if (!cb)
345 return;
346
347 clr.msg = nlmsg_alloc_simple(type, flags);
348 if (!clr.msg)
349 goto out;
350
351 nlmsg_append(clr.msg, &rtm, clr.size, 0);
352 nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_clear_event, &clr);
353 nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, cb_finish_event, &pending);
354 nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &pending);
355
356 nl_send_auto_complete(sock_rtnl, clr.msg);
357 while (pending > 0)
358 nl_recvmsgs(sock_rtnl, cb);
359
360 nlmsg_free(clr.msg);
361 out:
362 nl_cb_put(cb);
363 }
364
365 /*
366 * Clear bridge (membership) state and bring down device
367 */
368 void system_if_clear_state(struct device *dev)
369 {
370 char buf[256];
371 char *bridge;
372
373 dev->ifindex = system_if_resolve(dev);
374 if (!dev->ifindex)
375 return;
376
377 system_if_flags(dev->ifname, 0, IFF_UP);
378
379 if (system_is_bridge(dev->ifname, buf, sizeof(buf))) {
380 D(SYSTEM, "Delete existing bridge named '%s'\n", dev->ifname);
381 system_bridge_delbr(dev);
382 return;
383 }
384
385 bridge = system_get_bridge(dev->ifname, buf, sizeof(buf));
386 if (bridge) {
387 D(SYSTEM, "Remove device '%s' from bridge '%s'\n", dev->ifname, bridge);
388 system_bridge_if(bridge, dev, SIOCBRDELIF, NULL);
389 }
390
391 system_if_clear_entries(dev, RTM_GETROUTE, AF_INET);
392 system_if_clear_entries(dev, RTM_GETADDR, AF_INET);
393 system_if_clear_entries(dev, RTM_GETROUTE, AF_INET6);
394 system_if_clear_entries(dev, RTM_GETADDR, AF_INET6);
395 system_set_disable_ipv6(dev, "0");
396 }
397
398 static inline unsigned long
399 sec_to_jiffies(int val)
400 {
401 return (unsigned long) val * 100;
402 }
403
404 int system_bridge_addbr(struct device *bridge, struct bridge_config *cfg)
405 {
406 unsigned long args[4] = {};
407
408 if (ioctl(sock_ioctl, SIOCBRADDBR, bridge->ifname) < 0)
409 return -1;
410
411 args[0] = BRCTL_SET_BRIDGE_STP_STATE;
412 args[1] = !!cfg->stp;
413 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
414
415 args[0] = BRCTL_SET_BRIDGE_FORWARD_DELAY;
416 args[1] = sec_to_jiffies(cfg->forward_delay);
417 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
418
419 system_set_dev_sysctl("/sys/devices/virtual/net/%s/bridge/multicast_snooping",
420 bridge->ifname, cfg->igmp_snoop ? "1" : "0");
421
422 if (cfg->flags & BRIDGE_OPT_AGEING_TIME) {
423 args[0] = BRCTL_SET_AGEING_TIME;
424 args[1] = sec_to_jiffies(cfg->ageing_time);
425 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
426 }
427
428 if (cfg->flags & BRIDGE_OPT_HELLO_TIME) {
429 args[0] = BRCTL_SET_BRIDGE_HELLO_TIME;
430 args[1] = sec_to_jiffies(cfg->hello_time);
431 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
432 }
433
434 if (cfg->flags & BRIDGE_OPT_MAX_AGE) {
435 args[0] = BRCTL_SET_BRIDGE_MAX_AGE;
436 args[1] = sec_to_jiffies(cfg->max_age);
437 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
438 }
439
440 return 0;
441 }
442
443 static int system_vlan(struct device *dev, int id)
444 {
445 struct vlan_ioctl_args ifr = {
446 .cmd = SET_VLAN_NAME_TYPE_CMD,
447 .u.name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD,
448 };
449
450 ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
451
452 if (id < 0) {
453 ifr.cmd = DEL_VLAN_CMD;
454 ifr.u.VID = 0;
455 } else {
456 ifr.cmd = ADD_VLAN_CMD;
457 ifr.u.VID = id;
458 }
459 strncpy(ifr.device1, dev->ifname, sizeof(ifr.device1));
460 return ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
461 }
462
463 int system_vlan_add(struct device *dev, int id)
464 {
465 return system_vlan(dev, id);
466 }
467
468 int system_vlan_del(struct device *dev)
469 {
470 return system_vlan(dev, -1);
471 }
472
473 static void
474 system_if_apply_settings(struct device *dev)
475 {
476 struct ifreq ifr;
477
478 memset(&ifr, 0, sizeof(ifr));
479 strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
480 if (dev->flags & DEV_OPT_MTU) {
481 ifr.ifr_mtu = dev->mtu;
482 ioctl(sock_ioctl, SIOCSIFMTU, &ifr);
483 }
484 if (dev->flags & DEV_OPT_TXQUEUELEN) {
485 ifr.ifr_qlen = dev->txqueuelen;
486 ioctl(sock_ioctl, SIOCSIFTXQLEN, &ifr);
487 }
488 if (dev->flags & DEV_OPT_MACADDR) {
489 memcpy(&ifr.ifr_hwaddr, dev->macaddr, sizeof(dev->macaddr));
490 ioctl(sock_ioctl, SIOCSIFHWADDR, &ifr);
491 }
492
493 dev->ifindex = system_if_resolve(dev);
494 }
495
496 int system_if_up(struct device *dev)
497 {
498 system_if_apply_settings(dev);
499 return system_if_flags(dev->ifname, IFF_UP, 0);
500 }
501
502 int system_if_down(struct device *dev)
503 {
504 return system_if_flags(dev->ifname, 0, IFF_UP);
505 }
506
507 int system_if_check(struct device *dev)
508 {
509 device_set_present(dev, (system_if_resolve(dev) >= 0));
510 return 0;
511 }
512
513 int system_if_dump_stats(struct device *dev, struct blob_buf *b)
514 {
515 const char *const counters[] = {
516 "collisions", "rx_frame_errors", "tx_compressed",
517 "multicast", "rx_length_errors", "tx_dropped",
518 "rx_bytes", "rx_missed_errors", "tx_errors",
519 "rx_compressed", "rx_over_errors", "tx_fifo_errors",
520 "rx_crc_errors", "rx_packets", "tx_heartbeat_errors",
521 "rx_dropped", "tx_aborted_errors", "tx_packets",
522 "rx_errors", "tx_bytes", "tx_window_errors",
523 "rx_fifo_errors", "tx_carrier_errors",
524 };
525 char buf[64];
526 int stats_dir;
527 int i, fd, len;
528
529 snprintf(buf, sizeof(buf), "/sys/class/net/%s/statistics", dev->ifname);
530 stats_dir = open(buf, O_DIRECTORY);
531 if (stats_dir < 0)
532 return -1;
533
534 for (i = 0; i < ARRAY_SIZE(counters); i++) {
535 fd = openat(stats_dir, counters[i], O_RDONLY);
536 if (fd < 0)
537 continue;
538
539 retry:
540 len = read(fd, buf, sizeof(buf));
541 if (len < 0) {
542 if (errno == EINTR)
543 goto retry;
544 continue;
545 }
546
547 buf[len] = 0;
548 blobmsg_add_u32(b, counters[i], strtoul(buf, NULL, 0));
549 close(fd);
550 }
551
552 close(stats_dir);
553 return 0;
554 }
555
556 static int system_addr(struct device *dev, struct device_addr *addr, int cmd)
557 {
558 int alen = ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
559 struct ifaddrmsg ifa = {
560 .ifa_family = (alen == 4) ? AF_INET : AF_INET6,
561 .ifa_prefixlen = addr->mask,
562 .ifa_index = dev->ifindex,
563 };
564
565 struct nl_msg *msg;
566
567 dev = addr->device;
568 if (dev) {
569 if (!dev->ifindex)
570 return -1;
571
572 ifa.ifa_index = dev->ifindex;
573 }
574
575 msg = nlmsg_alloc_simple(cmd, 0);
576 if (!msg)
577 return -1;
578
579 nlmsg_append(msg, &ifa, sizeof(ifa), 0);
580 nla_put(msg, IFA_LOCAL, alen, &addr->addr);
581 return system_rtnl_call(msg);
582 }
583
584 int system_add_address(struct device *dev, struct device_addr *addr)
585 {
586 return system_addr(dev, addr, RTM_NEWADDR);
587 }
588
589 int system_del_address(struct device *dev, struct device_addr *addr)
590 {
591 return system_addr(dev, addr, RTM_DELADDR);
592 }
593
594 static int system_rt(struct device *dev, struct device_route *route, int cmd)
595 {
596 int alen = ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
597 bool have_gw;
598 unsigned int flags = 0;
599 int ifindex = dev->ifindex;
600
601 if (alen == 4)
602 have_gw = !!route->nexthop.in.s_addr;
603 else
604 have_gw = route->nexthop.in6.s6_addr32[0] ||
605 route->nexthop.in6.s6_addr32[1] ||
606 route->nexthop.in6.s6_addr32[2] ||
607 route->nexthop.in6.s6_addr32[3];
608
609 unsigned char scope = (cmd == RTM_DELROUTE) ? RT_SCOPE_NOWHERE :
610 (have_gw) ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK;
611
612 struct rtmsg rtm = {
613 .rtm_family = (alen == 4) ? AF_INET : AF_INET6,
614 .rtm_dst_len = route->mask,
615 .rtm_table = RT_TABLE_MAIN,
616 .rtm_protocol = RTPROT_BOOT,
617 .rtm_scope = scope,
618 .rtm_type = (cmd == RTM_DELROUTE) ? 0: RTN_UNICAST,
619 };
620 struct nl_msg *msg;
621
622 if (cmd == RTM_NEWROUTE)
623 flags |= NLM_F_CREATE | NLM_F_REPLACE;
624
625 dev = route->device;
626 if (dev) {
627 if (!dev->ifindex)
628 return -1;
629
630 ifindex = dev->ifindex;
631 }
632
633 msg = nlmsg_alloc_simple(cmd, flags);
634 if (!msg)
635 return -1;
636
637 nlmsg_append(msg, &rtm, sizeof(rtm), 0);
638
639 if (route->mask)
640 nla_put(msg, RTA_DST, alen, &route->addr);
641
642 if (have_gw)
643 nla_put(msg, RTA_GATEWAY, alen, &route->nexthop);
644
645 if (route->flags & DEVADDR_DEVICE)
646 nla_put_u32(msg, RTA_OIF, ifindex);
647
648 return system_rtnl_call(msg);
649 }
650
651 int system_add_route(struct device *dev, struct device_route *route)
652 {
653 return system_rt(dev, route, RTM_NEWROUTE);
654 }
655
656 int system_del_route(struct device *dev, struct device_route *route)
657 {
658 return system_rt(dev, route, RTM_DELROUTE);
659 }
660
661 int system_flush_routes(void)
662 {
663 const char *names[] = {
664 "/proc/sys/net/ipv4/route/flush",
665 "/proc/sys/net/ipv6/route/flush"
666 };
667 int fd, i;
668
669 for (i = 0; i < ARRAY_SIZE(names); i++) {
670 fd = open(names[i], O_WRONLY);
671 if (fd < 0)
672 continue;
673
674 write(fd, "-1", 2);
675 close(fd);
676 }
677 return 0;
678 }
679
680 time_t system_get_rtime(void)
681 {
682 struct timespec ts;
683 struct timeval tv;
684
685 if (syscall(__NR_clock_gettime, CLOCK_MONOTONIC, &ts) == 0)
686 return ts.tv_sec;
687
688 if (gettimeofday(&tv, NULL) == 0)
689 return tv.tv_sec;
690
691 return 0;
692 }