xref: /freebsd/sbin/route/route_netlink.c (revision 8ee579abe09ec1fe15c588fc9a08370b83b81cd6)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <string.h>
4 #include <err.h>
5 #include <errno.h>
6 
7 #include <sys/bitcount.h>
8 #include <sys/param.h>
9 #include <sys/linker.h>
10 #include <sys/module.h>
11 #include <sys/socket.h>
12 #include <sys/sysctl.h>
13 #include <sys/time.h>
14 #include <sys/types.h>
15 
16 #include <netinet/in.h>
17 #include <arpa/inet.h>
18 
19 #include <net/ethernet.h>
20 #include <net/if.h>
21 #include <net/if_dl.h>
22 #include <net/if_types.h>
23 #include <netlink/netlink.h>
24 #include <netlink/netlink_route.h>
25 #include <netlink/netlink_snl.h>
26 #include <netlink/netlink_snl_route.h>
27 #include <netlink/netlink_snl_route_compat.h>
28 #include <netlink/netlink_snl_route_parsers.h>
29 
30 const char *routename(struct sockaddr *);
31 const char *netname(struct sockaddr *);
32 void printb(int, const char *);
33 extern const char routeflags[];
34 extern int verbose, debugonly;
35 
36 int rtmsg_nl(int cmd, int rtm_flags, int fib, int rtm_addrs, struct sockaddr_storage *so,
37     struct rt_metrics *rt_metrics);
38 int flushroutes_fib_nl(int fib, int af);
39 void monitor_nl(int fib);
40 
41 struct nl_helper;
42 static void print_getmsg(struct nl_helper *h, struct nlmsghdr *hdr, struct sockaddr *dst);
43 static void print_nlmsg(struct nl_helper *h, struct nlmsghdr *hdr);
44 
45 #define s6_addr32 __u6_addr.__u6_addr32
46 #define	bitcount32(x)	__bitcount32((uint32_t)(x))
47 static int
48 inet6_get_plen(const struct in6_addr *addr)
49 {
50 
51 	return (bitcount32(addr->s6_addr32[0]) + bitcount32(addr->s6_addr32[1]) +
52 	    bitcount32(addr->s6_addr32[2]) + bitcount32(addr->s6_addr32[3]));
53 }
54 
55 static void
56 ip6_writemask(struct in6_addr *addr6, uint8_t mask)
57 {
58 	uint32_t *cp;
59 
60 	for (cp = (uint32_t *)addr6; mask >= 32; mask -= 32)
61 		*cp++ = 0xFFFFFFFF;
62 	if (mask > 0)
63 		*cp = htonl(mask ? ~((1 << (32 - mask)) - 1) : 0);
64 }
65 
66 static struct sockaddr *
67 get_netmask(struct snl_state *ss, int family, int plen)
68 {
69 	if (family == AF_INET) {
70 		if (plen == 32)
71 			return (NULL);
72 
73 		struct sockaddr_in *sin = snl_allocz(ss, sizeof(*sin));
74 
75 		sin->sin_len = sizeof(*sin);
76 		sin->sin_family = family;
77 		sin->sin_addr.s_addr = htonl(plen ? ~((1 << (32 - plen)) - 1) : 0);
78 
79 		return (struct sockaddr *)sin;
80 	} else if (family == AF_INET6) {
81 		if (plen == 128)
82 			return (NULL);
83 
84 		struct sockaddr_in6 *sin6 = snl_allocz(ss, sizeof(*sin6));
85 
86 		sin6->sin6_len = sizeof(*sin6);
87 		sin6->sin6_family = family;
88 		ip6_writemask(&sin6->sin6_addr, plen);
89 
90 		return (struct sockaddr *)sin6;
91 	}
92 	return (NULL);
93 }
94 
95 static void
96 nl_init_socket(struct snl_state *ss)
97 {
98 	if (snl_init(ss, NETLINK_ROUTE))
99 		return;
100 
101 	if (modfind("netlink") == -1 && errno == ENOENT) {
102 		/* Try to load */
103 		if (kldload("netlink") == -1)
104 			err(1, "netlink is not loaded and load attempt failed");
105 		if (snl_init(ss, NETLINK_ROUTE))
106 			return;
107 	}
108 
109 	err(1, "unable to open netlink socket");
110 }
111 
112 struct nl_helper {
113 	struct snl_state ss_cmd;
114 };
115 
116 static void
117 nl_helper_init(struct nl_helper *h)
118 {
119 	nl_init_socket(&h->ss_cmd);
120 }
121 
122 static void
123 nl_helper_free(struct nl_helper *h)
124 {
125 	snl_free(&h->ss_cmd);
126 }
127 
128 static struct sockaddr *
129 get_addr(struct sockaddr_storage *so, int rtm_addrs, int addr_type)
130 {
131 	struct sockaddr *sa = NULL;
132 
133 	if (rtm_addrs & (1 << addr_type))
134 		sa = (struct sockaddr *)&so[addr_type];
135 	return (sa);
136 }
137 
138 static int
139 rtmsg_nl_int(struct nl_helper *h, int cmd, int rtm_flags, int fib, int rtm_addrs,
140     struct sockaddr_storage *so, struct rt_metrics *rt_metrics)
141 {
142 	struct snl_state *ss = &h->ss_cmd;
143 	struct snl_writer nw;
144 	int nl_type = 0, nl_flags = 0;
145 
146 	snl_init_writer(ss, &nw);
147 
148 	switch (cmd) {
149 	case RTSOCK_RTM_ADD:
150 		nl_type = RTM_NEWROUTE;
151 		nl_flags = NLM_F_CREATE | NLM_F_APPEND; /* Do append by default */
152 		break;
153 	case RTSOCK_RTM_CHANGE:
154 		nl_type = RTM_NEWROUTE;
155 		nl_flags = NLM_F_REPLACE;
156 		break;
157 	case RTSOCK_RTM_DELETE:
158 		nl_type = RTM_DELROUTE;
159 		break;
160 	case RTSOCK_RTM_GET:
161 		nl_type = RTM_GETROUTE;
162 		break;
163 	default:
164 		exit(1);
165 	}
166 
167 	struct sockaddr *dst = get_addr(so, rtm_addrs, RTAX_DST);
168 	struct sockaddr *mask = get_addr(so, rtm_addrs, RTAX_NETMASK);
169 	struct sockaddr *gw = get_addr(so, rtm_addrs, RTAX_GATEWAY);
170 
171 	if (dst == NULL)
172 		return (EINVAL);
173 
174 	struct nlmsghdr *hdr = snl_create_msg_request(&nw, nl_type);
175 	hdr->nlmsg_flags |= nl_flags;
176 
177 	int plen = 0;
178 	int rtm_type = RTN_UNICAST;
179 
180 	switch (dst->sa_family) {
181 	case AF_INET:
182 	    {
183 		struct sockaddr_in *mask4 = (struct sockaddr_in *)mask;
184 
185 		if ((rtm_flags & RTF_HOST) == 0 && mask4 != NULL)
186 			plen = bitcount32(mask4->sin_addr.s_addr);
187 		else
188 			plen = 32;
189 		break;
190 	    }
191 	case AF_INET6:
192 	    {
193 		struct sockaddr_in6 *mask6 = (struct sockaddr_in6 *)mask;
194 
195 		if ((rtm_flags & RTF_HOST) == 0 && mask6 != NULL)
196 			plen = inet6_get_plen(&mask6->sin6_addr);
197 		else
198 			plen = 128;
199 		break;
200 	    }
201 	default:
202 		return (ENOTSUP);
203 	}
204 
205 	if (rtm_flags & RTF_REJECT)
206 		rtm_type = RTN_PROHIBIT;
207 	else if (rtm_flags & RTF_BLACKHOLE)
208 		rtm_type = RTN_BLACKHOLE;
209 
210 	struct rtmsg *rtm = snl_reserve_msg_object(&nw, struct rtmsg);
211 	rtm->rtm_family = dst->sa_family;
212 	rtm->rtm_protocol = RTPROT_STATIC;
213 	rtm->rtm_type = rtm_type;
214 	rtm->rtm_dst_len = plen;
215 
216 	/* Request exact prefix match if mask is set */
217 	if ((cmd == RTSOCK_RTM_GET) && (mask != NULL))
218 		rtm->rtm_flags = RTM_F_PREFIX;
219 
220 	snl_add_msg_attr_ip(&nw, RTA_DST, dst);
221 	snl_add_msg_attr_u32(&nw, RTA_TABLE, fib);
222 
223 	if (gw != NULL) {
224 		if (rtm_flags & RTF_GATEWAY) {
225 			if (gw->sa_family == dst->sa_family)
226 				snl_add_msg_attr_ip(&nw, RTA_GATEWAY, gw);
227 			else
228 				snl_add_msg_attr_ipvia(&nw, RTA_VIA, gw);
229 		} else {
230 			/* Should be AF_LINK */
231 			struct sockaddr_dl *sdl = (struct sockaddr_dl *)gw;
232 			if (sdl->sdl_index != 0)
233 				snl_add_msg_attr_u32(&nw, RTA_OIF, sdl->sdl_index);
234 		}
235 	}
236 
237 	if (rtm_flags != 0)
238 		snl_add_msg_attr_u32(&nw, NL_RTA_RTFLAGS, rtm_flags);
239 
240 	if (rt_metrics->rmx_mtu > 0) {
241 		int off = snl_add_msg_attr_nested(&nw, RTA_METRICS);
242 		snl_add_msg_attr_u32(&nw, RTAX_MTU, rt_metrics->rmx_mtu);
243 		snl_end_attr_nested(&nw, off);
244 	}
245 
246 	if (rt_metrics->rmx_weight > 0)
247 		snl_add_msg_attr_u32(&nw, NL_RTA_WEIGHT, rt_metrics->rmx_weight);
248 
249 	if (snl_finalize_msg(&nw) && snl_send_message(ss, hdr)) {
250 		struct snl_errmsg_data e = {};
251 
252 		hdr = snl_read_reply(ss, hdr->nlmsg_seq);
253 		if (nl_type == NL_RTM_GETROUTE) {
254 			if (hdr->nlmsg_type == NL_RTM_NEWROUTE)
255 				print_getmsg(h, hdr, dst);
256 			else {
257 				snl_parse_errmsg(ss, hdr, &e);
258 				if (e.error == ESRCH)
259 					warn("route has not been found");
260 				else
261 					warn("message indicates error %d", e.error);
262 			}
263 
264 			return (0);
265 		}
266 
267 		if (snl_parse_errmsg(ss, hdr, &e))
268 			return (e.error);
269 	}
270 	return (EINVAL);
271 }
272 
273 int
274 rtmsg_nl(int cmd, int rtm_flags, int fib, int rtm_addrs,
275     struct sockaddr_storage *so, struct rt_metrics *rt_metrics)
276 {
277 	struct nl_helper h = {};
278 
279 	nl_helper_init(&h);
280 	int error = rtmsg_nl_int(&h, cmd, rtm_flags, fib, rtm_addrs, so, rt_metrics);
281 	nl_helper_free(&h);
282 
283 	return (error);
284 }
285 
286 static void
287 get_ifdata(struct nl_helper *h, uint32_t ifindex, struct snl_parsed_link_simple *link)
288 {
289 	struct snl_state *ss = &h->ss_cmd;
290 	struct snl_writer nw;
291 
292 	snl_init_writer(ss, &nw);
293 	struct nlmsghdr *hdr = snl_create_msg_request(&nw, NL_RTM_GETLINK);
294 	struct ifinfomsg *ifmsg = snl_reserve_msg_object(&nw, struct ifinfomsg);
295 	if (ifmsg != NULL)
296 		ifmsg->ifi_index = ifindex;
297 	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
298 		return;
299 
300 	hdr = snl_read_reply(ss, hdr->nlmsg_seq);
301 
302 	if (hdr != NULL && hdr->nlmsg_type == RTM_NEWLINK) {
303 		snl_parse_nlmsg(ss, hdr, &snl_rtm_link_parser_simple, link);
304 	}
305 
306 	if (link->ifla_ifname == NULL) {
307 		char ifname[16];
308 
309 		snprintf(ifname, sizeof(ifname), "if#%u", ifindex);
310 		int len = strlen(ifname);
311 		char *buf = snl_allocz(ss, len + 1);
312 		strlcpy(buf, ifname, len + 1);
313 		link->ifla_ifname = buf;
314 	}
315 }
316 
317 static void
318 print_getmsg(struct nl_helper *h, struct nlmsghdr *hdr, struct sockaddr *dst)
319 {
320 	struct snl_state *ss = &h->ss_cmd;
321 	struct timespec ts;
322 	struct snl_parsed_route r = { .rtax_weight = RT_DEFAULT_WEIGHT };
323 
324 	if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_route_parser, &r))
325 		return;
326 
327 	struct snl_parsed_link_simple link = {};
328 	get_ifdata(h, r.rta_oif, &link);
329 
330 	if (r.rtax_mtu == 0)
331 		r.rtax_mtu = link.ifla_mtu;
332 	r.rta_rtflags |= (RTF_UP | RTF_DONE);
333 
334 	(void)printf("   route to: %s\n", routename(dst));
335 
336 	if (r.rta_dst)
337 		(void)printf("destination: %s\n", routename(r.rta_dst));
338 	struct sockaddr *mask = get_netmask(ss, r.rtm_family, r.rtm_dst_len);
339 	if (mask)
340 		(void)printf("       mask: %s\n", routename(mask));
341 	if (r.rta_gw && (r.rta_rtflags & RTF_GATEWAY))
342 		(void)printf("    gateway: %s\n", routename(r.rta_gw));
343 	(void)printf("        fib: %u\n", (unsigned int)r.rta_table);
344 	if (link.ifla_ifname)
345 		(void)printf("  interface: %s\n", link.ifla_ifname);
346 	(void)printf("      flags: ");
347 	printb(r.rta_rtflags, routeflags);
348 
349 	struct rt_metrics rmx = {
350 		.rmx_mtu = r.rtax_mtu,
351 		.rmx_weight = r.rtax_weight,
352 		.rmx_expire = r.rta_expire,
353 	};
354 
355 	printf("\n%9s %9s %9s %9s %9s %10s %9s\n", "recvpipe",
356 	    "sendpipe", "ssthresh", "rtt,msec", "mtu   ", "weight", "expire");
357 	printf("%8lu  ", rmx.rmx_recvpipe);
358 	printf("%8lu  ", rmx.rmx_sendpipe);
359 	printf("%8lu  ", rmx.rmx_ssthresh);
360 	printf("%8lu  ", 0UL);
361 	printf("%8lu  ", rmx.rmx_mtu);
362 	printf("%8lu  ", rmx.rmx_weight);
363 	if (rmx.rmx_expire > 0)
364 		clock_gettime(CLOCK_REALTIME_FAST, &ts);
365 	else
366 		ts.tv_sec = 0;
367 	printf("%8ld \n", (long)(rmx.rmx_expire - ts.tv_sec));
368 }
369 
370 static void
371 print_prefix(struct nl_helper *h, char *buf, int bufsize, struct sockaddr *sa, int plen)
372 {
373 	int sz = 0;
374 
375 	if (sa == NULL) {
376 		snprintf(buf, bufsize, "<NULL>");
377 		return;
378 	}
379 
380 	switch (sa->sa_family) {
381 	case AF_INET:
382 		{
383 			struct sockaddr_in *sin = (struct sockaddr_in *)sa;
384 			char abuf[INET_ADDRSTRLEN];
385 
386 			inet_ntop(AF_INET, &sin->sin_addr, abuf, sizeof(abuf));
387 			sz = snprintf(buf, bufsize, "%s", abuf);
388 			break;
389 		}
390 	case AF_INET6:
391 		{
392 			struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa;
393 			char abuf[INET6_ADDRSTRLEN];
394 			char *ifname = NULL;
395 
396 			inet_ntop(AF_INET6, &sin6->sin6_addr, abuf, sizeof(abuf));
397 			if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
398 				struct snl_parsed_link_simple link = {};
399 
400 				if (sin6->sin6_scope_id != 0) {
401 					get_ifdata(h, sin6->sin6_scope_id, &link);
402 					ifname = link.ifla_ifname;
403 				}
404 			}
405 			if (ifname == NULL)
406 				sz = snprintf(buf, bufsize, "%s", abuf);
407 			else
408 				sz = snprintf(buf, bufsize, "%s%%%s", abuf, ifname);
409 			break;
410 		}
411 	default:
412 		snprintf(buf, bufsize, "unknown_af#%d", sa->sa_family);
413 		plen = -1;
414 	}
415 
416 	if (plen >= 0)
417 		snprintf(buf + sz, bufsize - sz, "/%d", plen);
418 }
419 
420 
421 static int
422 print_line_prefix(const char *cmd, const char *name)
423 {
424 	struct timespec tp;
425 	struct tm tm;
426 	char buf[32];
427 
428 	clock_gettime(CLOCK_REALTIME, &tp);
429 	localtime_r(&tp.tv_sec, &tm);
430 
431 	strftime(buf, sizeof(buf), "%T", &tm);
432 	int len = printf("%s.%03ld %s %s ", buf, tp.tv_nsec / 1000000, cmd, name);
433 
434 	return (len);
435 }
436 
437 static const char *
438 get_action_name(struct nlmsghdr *hdr, int new_cmd)
439 {
440 	if (hdr->nlmsg_type == new_cmd) {
441 		//return ((hdr->nlmsg_flags & NLM_F_REPLACE) ? "replace" : "add");
442 		return ("add/repl");
443 	} else
444 		return ("delete");
445 }
446 
447 static void
448 print_nlmsg_route_nhop(struct nl_helper *h, struct snl_parsed_route *r,
449     struct rta_mpath_nh *nh, bool first)
450 {
451 	// gw 10.0.0.1 ifp vtnet0 mtu 1500 table inet.0
452 	if (nh->gw != NULL) {
453 		char gwbuf[128];
454 		print_prefix(h, gwbuf, sizeof(gwbuf), nh->gw, -1);
455 		printf("gw %s ", gwbuf);
456 	}
457 
458 	if (nh->ifindex != 0) {
459 		struct snl_parsed_link_simple link = {};
460 
461 		get_ifdata(h, nh->ifindex, &link);
462 		if (nh->rtax_mtu == 0)
463 			nh->rtax_mtu = link.ifla_mtu;
464 		printf("iface %s ", link.ifla_ifname);
465 		if (nh->rtax_mtu != 0)
466 			printf("mtu %d ", nh->rtax_mtu);
467 	}
468 
469 	if (first) {
470 		switch (r->rtm_family) {
471 			case AF_INET:
472 				printf("table inet.%d", r->rta_table);
473 				break;
474 			case AF_INET6:
475 				printf("table inet6.%d", r->rta_table);
476 				break;
477 		}
478 	}
479 
480 	printf("\n");
481 }
482 
483 static void
484 print_nlmsg_route(struct nl_helper *h, struct nlmsghdr *hdr)
485 {
486 	struct snl_parsed_route r = { .rtax_weight = RT_DEFAULT_WEIGHT };
487 	struct snl_state *ss = &h->ss_cmd;
488 
489 	if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_route_parser, &r))
490 		return;
491 
492 	// 20:19:41.333 add route 10.0.0.0/24 gw 10.0.0.1 ifp vtnet0 mtu 1500 table inet.0
493 
494 	const char *cmd = get_action_name(hdr, RTM_NEWROUTE);
495 	int len = print_line_prefix(cmd, "route");
496 
497 	char buf[128];
498 	print_prefix(h, buf, sizeof(buf), r.rta_dst, r.rtm_dst_len);
499 	len += strlen(buf) + 1;
500 	printf("%s ", buf);
501 
502 	switch (r.rtm_type) {
503 	case RTN_BLACKHOLE:
504 		printf("blackhole\n");
505 		return;
506 	case RTN_UNREACHABLE:
507 		printf("unreach(reject)\n");
508 		return;
509 	case RTN_PROHIBIT:
510 		printf("prohibit(reject)\n");
511 		return;
512 	}
513 
514 	if (r.rta_multipath != NULL) {
515 		bool first = true;
516 
517 		memset(buf, ' ', sizeof(buf));
518 		buf[len] = '\0';
519 
520 		for (int i = 0; i < r.rta_multipath->num_nhops; i++) {
521 			struct rta_mpath_nh *nh = &r.rta_multipath->nhops[i];
522 
523 			if (!first)
524 				printf("%s", buf);
525 			print_nlmsg_route_nhop(h, &r, nh, first);
526 			first = false;
527 		}
528 	} else {
529 		struct rta_mpath_nh nh = {
530 			.gw = r.rta_gw,
531 			.ifindex = r.rta_oif,
532 			.rtax_mtu = r.rtax_mtu,
533 		};
534 
535 		print_nlmsg_route_nhop(h, &r, &nh, true);
536 	}
537 }
538 
539 static const char *operstate[] = {
540 	"UNKNOWN",	/* 0, IF_OPER_UNKNOWN */
541 	"NOTPRESENT",	/* 1, IF_OPER_NOTPRESENT */
542 	"DOWN",		/* 2, IF_OPER_DOWN */
543 	"LLDOWN",	/* 3, IF_OPER_LOWERLAYERDOWN */
544 	"TESTING",	/* 4, IF_OPER_TESTING */
545 	"DORMANT",	/* 5, IF_OPER_DORMANT */
546 	"UP",		/* 6, IF_OPER_UP */
547 };
548 
549 static void
550 print_nlmsg_link(struct nl_helper *h, struct nlmsghdr *hdr)
551 {
552 	struct snl_parsed_link l = {};
553 	struct snl_state *ss = &h->ss_cmd;
554 
555 	if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_link_parser, &l))
556 		return;
557 
558 	// 20:19:41.333 add iface#3 vtnet0 admin UP oper UP mtu 1500 table inet.0
559 	const char *cmd = get_action_name(hdr, RTM_NEWLINK);
560 	print_line_prefix(cmd, "iface");
561 
562 	printf("iface#%u %s ", l.ifi_index, l.ifla_ifname);
563 	printf("admin %s ", (l.ifi_flags & IFF_UP) ? "UP" : "DOWN");
564 	if (l.ifla_operstate < NL_ARRAY_LEN(operstate))
565 		printf("oper %s ", operstate[l.ifla_operstate]);
566 	if (l.ifla_mtu > 0)
567 		printf("mtu %u ", l.ifla_mtu);
568 
569 	printf("\n");
570 }
571 
572 static void
573 print_nlmsg_addr(struct nl_helper *h, struct nlmsghdr *hdr)
574 {
575 	struct snl_parsed_addr attrs = {};
576 	struct snl_state *ss = &h->ss_cmd;
577 
578 	if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_addr_parser, &attrs))
579 		return;
580 
581 	// add addr 192.168.1.1/24 iface vtnet0
582 	const char *cmd = get_action_name(hdr, RTM_NEWADDR);
583 	print_line_prefix(cmd, "addr");
584 
585 	char buf[128];
586 	struct sockaddr *addr = attrs.ifa_local ? attrs.ifa_local : attrs.ifa_address;
587 	print_prefix(h, buf, sizeof(buf), addr, attrs.ifa_prefixlen);
588 	printf("%s ", buf);
589 
590 	struct snl_parsed_link_simple link = {};
591 	get_ifdata(h, attrs.ifa_index, &link);
592 
593 	if (link.ifi_flags & IFF_POINTOPOINT) {
594 		char buf[64];
595 		print_prefix(h, buf, sizeof(buf), attrs.ifa_address, -1);
596 		printf("-> %s ", buf);
597 	}
598 
599 	printf("iface %s ", link.ifla_ifname);
600 
601 	printf("\n");
602 }
603 
604 static const char *nudstate[] = {
605 	"INCOMPLETE",		/* 0x01(0) */
606 	"REACHABLE",		/* 0x02(1) */
607 	"STALE",		/* 0x04(2) */
608 	"DELAY",		/* 0x08(3) */
609 	"PROBE",		/* 0x10(4) */
610 	"FAILED",		/* 0x20(5) */
611 };
612 
613 #define	NUD_INCOMPLETE		0x01	/* No lladdr, address resolution in progress */
614 #define	NUD_REACHABLE		0x02	/* reachable & recently resolved */
615 #define	NUD_STALE		0x04	/* has lladdr but it's stale */
616 #define	NUD_DELAY		0x08	/* has lladdr, is stale, probes delayed */
617 #define	NUD_PROBE		0x10	/* has lladdr, is stale, probes sent */
618 #define	NUD_FAILED		0x20	/* unused */
619 
620 
621 static void
622 print_nlmsg_neigh(struct nl_helper *h, struct nlmsghdr *hdr)
623 {
624 	struct snl_parsed_neigh attrs = {};
625 	struct snl_state *ss = &h->ss_cmd;
626 
627 	if (!snl_parse_nlmsg(ss, hdr, &snl_rtm_neigh_parser, &attrs))
628 		return;
629 
630 	// add addr 192.168.1.1 state %s lladdr %s iface vtnet0
631 	const char *cmd = get_action_name(hdr, RTM_NEWNEIGH);
632 	print_line_prefix(cmd, "neigh");
633 
634 	char buf[128];
635 	print_prefix(h, buf, sizeof(buf), attrs.nda_dst, -1);
636 	printf("%s ", buf);
637 
638 	struct snl_parsed_link_simple link = {};
639 	get_ifdata(h, attrs.nda_ifindex, &link);
640 
641 	for (unsigned int i = 0; i < NL_ARRAY_LEN(nudstate); i++) {
642 		if ((1 << i) & attrs.ndm_state) {
643 			printf("state %s ", nudstate[i]);
644 			break;
645 		}
646 	}
647 
648 	if (attrs.nda_lladdr != NULL) {
649 		int if_type = link.ifi_type;
650 
651 		if ((if_type == IFT_ETHER || if_type == IFT_L2VLAN || if_type == IFT_BRIDGE) &&
652 		    NLA_DATA_LEN(attrs.nda_lladdr) == ETHER_ADDR_LEN) {
653 			struct ether_addr *ll;
654 
655 			ll = (struct ether_addr *)NLA_DATA(attrs.nda_lladdr);
656 			printf("lladdr %s ", ether_ntoa(ll));
657 		} else {
658 			struct sockaddr_dl sdl = {
659 				.sdl_len = sizeof(sdl),
660 				.sdl_family = AF_LINK,
661 				.sdl_index = attrs.nda_ifindex,
662 				.sdl_type = if_type,
663 				.sdl_alen = NLA_DATA_LEN(attrs.nda_lladdr),
664 			};
665 			if (sdl.sdl_alen < sizeof(sdl.sdl_data)) {
666 				void *ll = NLA_DATA(attrs.nda_lladdr);
667 
668 				memcpy(sdl.sdl_data, ll, sdl.sdl_alen);
669 				printf("lladdr %s ", link_ntoa(&sdl));
670 			}
671 		}
672 	}
673 
674 	if (link.ifla_ifname != NULL)
675 		printf("iface %s ", link.ifla_ifname);
676 	printf("\n");
677 }
678 
679 static void
680 print_nlmsg_generic(struct nl_helper *h, struct nlmsghdr *hdr)
681 {
682 }
683 
684 static void
685 print_nlmsg(struct nl_helper *h, struct nlmsghdr *hdr)
686 {
687 	switch (hdr->nlmsg_type) {
688 	case RTM_NEWLINK:
689 	case RTM_DELLINK:
690 		print_nlmsg_link(h, hdr);
691 		break;
692 	case RTM_NEWADDR:
693 	case RTM_DELADDR:
694 		print_nlmsg_addr(h, hdr);
695 		break;
696 	case RTM_NEWROUTE:
697 	case RTM_DELROUTE:
698 		print_nlmsg_route(h, hdr);
699 		break;
700 	case RTM_NEWNEIGH:
701 	case RTM_DELNEIGH:
702 		print_nlmsg_neigh(h, hdr);
703 		break;
704 	default:
705 		print_nlmsg_generic(h, hdr);
706 	}
707 
708 	snl_clear_lb(&h->ss_cmd);
709 }
710 
711 void
712 monitor_nl(int fib)
713 {
714 	struct snl_state ss_event = {};
715 	struct nl_helper h;
716 
717 	nl_init_socket(&ss_event);
718 	nl_helper_init(&h);
719 
720 	int groups[] = {
721 		RTNLGRP_LINK,
722 		RTNLGRP_NEIGH,
723 		RTNLGRP_NEXTHOP,
724 #ifdef INET
725 		RTNLGRP_IPV4_IFADDR,
726 		RTNLGRP_IPV4_ROUTE,
727 #endif
728 #ifdef INET6
729 		RTNLGRP_IPV6_IFADDR,
730 		RTNLGRP_IPV6_ROUTE,
731 #endif
732 	};
733 
734 	for (unsigned int i = 0; i < NL_ARRAY_LEN(groups); i++) {
735 		int error;
736 		int optval = groups[i];
737 		socklen_t optlen = sizeof(optval);
738 		error = setsockopt(ss_event.fd, SOL_NETLINK,
739 		    NETLINK_ADD_MEMBERSHIP, &optval, optlen);
740 		if (error != 0)
741 			warn("Unable to subscribe to group %d", optval);
742 	}
743 
744 	struct nlmsghdr *hdr;
745 	while ((hdr = snl_read_message(&ss_event)) != NULL)
746 	{
747 		// printf("-- MSG type %d--\n", hdr->nlmsg_type);
748 		print_nlmsg(&h, hdr);
749 		snl_clear_lb(&h.ss_cmd);
750 		snl_clear_lb(&ss_event);
751 	}
752 
753 	snl_free(&ss_event);
754 	nl_helper_free(&h);
755 	exit(0);
756 }
757 
758 static void
759 print_flushed_route(struct snl_parsed_route *r, struct sockaddr *gw)
760 {
761 	struct sockaddr *sa = r->rta_dst;
762 
763 	printf("%-20.20s ", r->rta_rtflags & RTF_HOST ?
764 	    routename(sa) : netname(sa));
765 	sa = gw;
766 	printf("%-20.20s ", routename(sa));
767 	if (r->rta_table >= 0)
768 		printf("-fib %-3d ", r->rta_table);
769 	printf("done\n");
770 }
771 
772 static int
773 flushroute_one(struct nl_helper *h, struct snl_parsed_route *r)
774 {
775 	struct snl_state *ss = &h->ss_cmd;
776 	struct snl_errmsg_data e = {};
777 	struct snl_writer nw;
778 
779 	snl_init_writer(ss, &nw);
780 
781 	struct nlmsghdr *hdr = snl_create_msg_request(&nw, NL_RTM_DELROUTE);
782 	struct rtmsg *rtm = snl_reserve_msg_object(&nw, struct rtmsg);
783 	rtm->rtm_family = r->rtm_family;
784 	rtm->rtm_dst_len = r->rtm_dst_len;
785 
786 	snl_add_msg_attr_u32(&nw, RTA_TABLE, r->rta_table);
787 	snl_add_msg_attr_ip(&nw, RTA_DST, r->rta_dst);
788 
789 	if (!snl_finalize_msg(&nw) || !snl_send_message(ss, hdr))
790 		return (ENOMEM);
791 
792 	if (!snl_read_reply_code(ss, hdr->nlmsg_seq, &e)) {
793 		return (e.error);
794 		if (e.error == EPERM)
795 			errc(1, e.error, "RTM_DELROUTE failed:");
796 		else
797 			warnc(e.error, "RTM_DELROUTE failed:");
798 		return (true);
799 	};
800 
801 	if (verbose)
802 		print_nlmsg(h, hdr);
803 	else {
804 		if (r->rta_multipath != NULL) {
805 			for (int i = 0; i < r->rta_multipath->num_nhops; i++) {
806 				struct rta_mpath_nh *nh = &r->rta_multipath->nhops[i];
807 
808 				print_flushed_route(r, nh->gw);
809 			}
810 
811 		} else
812 			print_flushed_route(r, r->rta_gw);
813 	}
814 
815 	return (0);
816 }
817 
818 int
819 flushroutes_fib_nl(int fib, int af)
820 {
821 	struct snl_state ss = {};
822 	struct snl_writer nw;
823 	struct nl_helper h = {};
824 
825 	nl_init_socket(&ss);
826 	snl_init_writer(&ss, &nw);
827 
828 	struct nlmsghdr *hdr = snl_create_msg_request(&nw, NL_RTM_GETROUTE);
829 	hdr->nlmsg_flags |= NLM_F_DUMP;
830 	struct rtmsg *rtm = snl_reserve_msg_object(&nw, struct rtmsg);
831 	rtm->rtm_family = af;
832 	snl_add_msg_attr_u32(&nw, RTA_TABLE, fib);
833 
834 	if (!snl_finalize_msg(&nw) || !snl_send_message(&ss, hdr)) {
835 		snl_free(&ss);
836 		return (EINVAL);
837 	}
838 
839 	struct snl_errmsg_data e = {};
840 	uint32_t nlm_seq = hdr->nlmsg_seq;
841 
842 	nl_helper_init(&h);
843 
844 	while ((hdr = snl_read_reply_multi(&ss, nlm_seq, &e)) != NULL) {
845 		struct snl_parsed_route r = { .rtax_weight = RT_DEFAULT_WEIGHT };
846 		int error;
847 
848 		if (!snl_parse_nlmsg(&ss, hdr, &snl_rtm_route_parser, &r))
849 			continue;
850 		if (verbose)
851 			print_nlmsg(&h, hdr);
852 		if (r.rta_table != (uint32_t)fib || r.rtm_family != af)
853 			continue;
854 		if ((r.rta_rtflags & RTF_GATEWAY) == 0)
855 			continue;
856 		if (debugonly)
857 			continue;
858 
859 		if ((error = flushroute_one(&h, &r)) != 0) {
860 			if (error == EPERM)
861 				errc(1, error, "RTM_DELROUTE failed:");
862 			else
863 				warnc(error, "RTM_DELROUTE failed:");
864 		}
865 		snl_clear_lb(&h.ss_cmd);
866 	}
867 
868 	snl_free(&ss);
869 	nl_helper_free(&h);
870 
871 	return (e.error);
872 }
873 
874