xref: /netbsd-src/sys/net/rtsock.c (revision 7330f729ccf0bd976a06f95fad452fe774fc7fd1)
1 /*	$NetBSD: rtsock.c,v 1.252 2019/09/01 18:54:38 roy Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1988, 1991, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)rtsock.c	8.7 (Berkeley) 10/12/95
61  */
62 
63 #include <sys/cdefs.h>
64 __KERNEL_RCSID(0, "$NetBSD: rtsock.c,v 1.252 2019/09/01 18:54:38 roy Exp $");
65 
66 #ifdef _KERNEL_OPT
67 #include "opt_inet.h"
68 #include "opt_compat_netbsd.h"
69 #endif
70 
71 #include <sys/param.h>
72 #include <sys/systm.h>
73 #include <sys/proc.h>
74 #include <sys/socket.h>
75 #include <sys/socketvar.h>
76 #include <sys/domain.h>
77 #include <sys/protosw.h>
78 #include <sys/sysctl.h>
79 #include <sys/kauth.h>
80 #include <sys/kmem.h>
81 #include <sys/intr.h>
82 #include <sys/condvar.h>
83 #include <sys/compat_stub.h>
84 
85 #include <net/if.h>
86 #include <net/if_llatbl.h>
87 #include <net/if_types.h>
88 #include <net/route.h>
89 #include <net/raw_cb.h>
90 
91 #include <netinet/in_var.h>
92 #include <netinet/if_inarp.h>
93 
94 #include <netmpls/mpls.h>
95 
96 #include <compat/net/if.h>
97 #include <compat/net/route.h>
98 
99 #ifdef COMPAT_RTSOCK
100 #undef COMPAT_RTSOCK
101 #endif
102 
103 static int if_addrflags(struct ifaddr *);
104 
105 #include <net/rtsock_shared.c>
106 
107 /*
108  * XXX avoid using void * once msghdr compat disappears.
109  */
110 void
111 rt_setmetrics(void *in, struct rtentry *out)
112 {
113 	const struct rt_xmsghdr *rtm = in;
114 
115 	_rt_setmetrics(rtm->rtm_inits, rtm, out);
116 }
117 
118 int
119 rt_msg3(int type, struct rt_addrinfo *rtinfo, void *cpv, struct rt_walkarg *w,
120 	int *lenp)
121 {
122 	return rt_msg2(type, rtinfo, cpv, w, lenp);
123 }
124 
125 static int
126 if_addrflags(struct ifaddr *ifa)
127 {
128 
129 	switch (ifa->ifa_addr->sa_family) {
130 #ifdef INET
131 	case AF_INET:
132 		return ((struct in_ifaddr *)ifa)->ia4_flags;
133 #endif
134 #ifdef INET6
135 	case AF_INET6:
136 		return ((struct in6_ifaddr *)ifa)->ia6_flags;
137 #endif
138 	default:
139 		return 0;
140 	}
141 }
142 
143 
144 /*
145  * Send a routing message as mimicing that a cloned route is added.
146  */
147 void
148 rt_clonedmsg(int type, const struct sockaddr *dst, const uint8_t *lladdr,
149     const struct ifnet *ifp)
150 {
151 	struct rt_addrinfo info;
152 	/* Mimic flags exactly */
153 #define RTF_LLINFO	0x400
154 #define RTF_CLONED	0x2000
155 	int flags = RTF_DONE;
156 	union {
157 		struct sockaddr sa;
158 		struct sockaddr_storage ss;
159 		struct sockaddr_dl sdl;
160 	} u;
161 
162 	if (type != RTM_MISS)
163 		flags |= RTF_HOST | RTF_CLONED | RTF_LLINFO;
164 	if (type == RTM_ADD || type == RTM_CHANGE)
165 		flags |= RTF_UP;
166 	memset(&info, 0, sizeof(info));
167 	info.rti_info[RTAX_DST] = dst;
168 	sockaddr_dl_init(&u.sdl, sizeof(u.ss), ifp->if_index, ifp->if_type,
169 	    NULL, 0, lladdr, ifp->if_addrlen);
170 	info.rti_info[RTAX_GATEWAY] = &u.sa;
171 
172 	rt_missmsg(type, &info, flags, 0);
173 #undef RTF_LLINFO
174 #undef RTF_CLONED
175 }
176 
177 
178 /*
179  * The remaining code implements the routing-table sysctl node.  It is
180  * compiled only for the non-COMPAT case.
181  */
182 
183 /*
184  * This is used in dumping the kernel table via sysctl().
185  */
186 static int
187 sysctl_dumpentry(struct rtentry *rt, void *v)
188 {
189 	struct rt_walkarg *w = v;
190 	int error = 0, size;
191 	struct rt_addrinfo info;
192 
193 	if (w->w_op == NET_RT_FLAGS && !(rt->rt_flags & w->w_arg))
194 		return 0;
195 	memset(&info, 0, sizeof(info));
196 	info.rti_info[RTAX_DST] = rt_getkey(rt);
197 	info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
198 	info.rti_info[RTAX_NETMASK] = rt_mask(rt);
199 	info.rti_info[RTAX_TAG] = rt_gettag(rt);
200 	if (rt->rt_ifp) {
201 		const struct ifaddr *rtifa;
202 		info.rti_info[RTAX_IFP] = rt->rt_ifp->if_dl->ifa_addr;
203 		/* rtifa used to be simply rt->rt_ifa.  If rt->rt_ifa != NULL,
204 		 * then rt_get_ifa() != NULL.  So this ought to still be safe.
205 		 * --dyoung
206 		 */
207 		rtifa = rt_get_ifa(rt);
208 		info.rti_info[RTAX_IFA] = rtifa->ifa_addr;
209 		if (rt->rt_ifp->if_flags & IFF_POINTOPOINT)
210 			info.rti_info[RTAX_BRD] = rtifa->ifa_dstaddr;
211 	}
212 	if ((error = rt_msg2(RTM_GET, &info, 0, w, &size)))
213 		return error;
214 	if (w->w_where && w->w_tmem && w->w_needed <= 0) {
215 		struct rt_xmsghdr *rtm = (struct rt_xmsghdr *)w->w_tmem;
216 
217 		rtm->rtm_flags = rt->rt_flags;
218 		rtm->rtm_use = rt->rt_use;
219 		rtm_setmetrics(rt, rtm);
220 		KASSERT(rt->rt_ifp != NULL);
221 		rtm->rtm_index = rt->rt_ifp->if_index;
222 		rtm->rtm_errno = rtm->rtm_pid = rtm->rtm_seq = 0;
223 		rtm->rtm_addrs = info.rti_addrs;
224 		if ((error = copyout(rtm, w->w_where, size)) != 0)
225 			w->w_where = NULL;
226 		else
227 			w->w_where = (char *)w->w_where + size;
228 	}
229 	return error;
230 }
231 
232 static int
233 sysctl_iflist_if(struct ifnet *ifp, struct rt_walkarg *w,
234     struct rt_addrinfo *info, size_t len)
235 {
236 	struct if_xmsghdr *ifm;
237 	int error;
238 
239 	ifm = (struct if_xmsghdr *)w->w_tmem;
240 	ifm->ifm_index = ifp->if_index;
241 	ifm->ifm_flags = ifp->if_flags;
242 	ifm->ifm_data = ifp->if_data;
243 	ifm->ifm_addrs = info->rti_addrs;
244 	if ((error = copyout(ifm, w->w_where, len)) == 0)
245 		w->w_where = (char *)w->w_where + len;
246 	return error;
247 }
248 
249 static int
250 sysctl_iflist_addr(struct rt_walkarg *w, struct ifaddr *ifa,
251      struct rt_addrinfo *info)
252 {
253 	int len, error;
254 
255 	if ((error = rt_msg2(RTM_XNEWADDR, info, 0, w, &len)))
256 		return error;
257 	if (w->w_where && w->w_tmem && w->w_needed <= 0) {
258 		struct ifa_xmsghdr *ifam;
259 
260 		ifam = (struct ifa_xmsghdr *)w->w_tmem;
261 		ifam->ifam_index = ifa->ifa_ifp->if_index;
262 		ifam->ifam_flags = ifa->ifa_flags;
263 		ifam->ifam_metric = ifa->ifa_metric;
264 		ifam->ifam_addrs = info->rti_addrs;
265 		ifam->ifam_pid = 0;
266 		ifam->ifam_addrflags = if_addrflags(ifa);
267 		if ((error = copyout(w->w_tmem, w->w_where, len)) == 0)
268 			w->w_where = (char *)w->w_where + len;
269 	}
270 	return error;
271 }
272 
273 static int
274 sysctl_iflist(int af, struct rt_walkarg *w, int type)
275 {
276 	struct ifnet *ifp;
277 	struct ifaddr *ifa;
278 	struct	rt_addrinfo info;
279 	int	cmd, len, error = 0;
280 	int s;
281 	struct psref psref;
282 	int bound;
283 
284 	switch (type) {
285 	case NET_RT_IFLIST:
286 		cmd = RTM_IFINFO;
287 		break;
288 	case NET_RT_OOOIFLIST:
289 		cmd = RTM_OOIFINFO;
290 		break;
291 	case NET_RT_OOIFLIST:
292 		cmd = RTM_OIFINFO;
293 		break;
294 	case NET_RT_OIFLIST:
295 		cmd = RTM_IFINFO;
296 		break;
297 	default:
298 #ifdef RTSOCK_DEBUG
299 		printf("%s: unsupported IFLIST type %d\n", __func__, type);
300 #endif
301 		return EINVAL;
302 	}
303 
304 	memset(&info, 0, sizeof(info));
305 
306 	bound = curlwp_bind();
307 	s = pserialize_read_enter();
308 	IFNET_READER_FOREACH(ifp) {
309 		int _s;
310 		if (w->w_arg && w->w_arg != ifp->if_index)
311 			continue;
312 		if (IFADDR_READER_EMPTY(ifp))
313 			continue;
314 
315 		if_acquire(ifp, &psref);
316 		pserialize_read_exit(s);
317 
318 		info.rti_info[RTAX_IFP] = ifp->if_dl->ifa_addr;
319 		if ((error = rt_msg2(cmd, &info, NULL, w, &len)) != 0)
320 			goto release_exit;
321 		info.rti_info[RTAX_IFP] = NULL;
322 		if (w->w_where && w->w_tmem && w->w_needed <= 0) {
323 			switch (type) {
324 			case NET_RT_OIFLIST: /* old _70 */
325 				if (!rtsock_iflist_70_hook.hooked) {
326 					error = EINVAL;
327 					break;
328 				}
329 				/* FALLTHROUGH */
330 			case NET_RT_IFLIST: /* current */
331 				error = sysctl_iflist_if(ifp, w, &info, len);
332 				break;
333 			case NET_RT_OOIFLIST: /* old _50 */
334 				MODULE_HOOK_CALL(rtsock_iflist_50_hook,
335 				    (ifp, w, &info, len), enosys(), error);
336 				break;
337 			case NET_RT_OOOIFLIST: /* old _14 */
338 				MODULE_HOOK_CALL(rtsock_iflist_14_hook,
339 				   (ifp, w, &info, len), enosys(), error);
340 				break;
341 			default:
342 				error = EINVAL;
343 			}
344 			if (error != 0) {
345 				if (error == ENOSYS)
346 					error = EINVAL;
347 				goto release_exit;
348 			}
349 		}
350 		_s = pserialize_read_enter();
351 		IFADDR_READER_FOREACH(ifa, ifp) {
352 			struct psref _psref;
353 			if (af && af != ifa->ifa_addr->sa_family)
354 				continue;
355 			ifa_acquire(ifa, &_psref);
356 			pserialize_read_exit(_s);
357 
358 			info.rti_info[RTAX_IFA] = ifa->ifa_addr;
359 			info.rti_info[RTAX_NETMASK] = ifa->ifa_netmask;
360 			info.rti_info[RTAX_BRD] = ifa->ifa_dstaddr;
361 			switch (type) {
362 			case NET_RT_IFLIST:
363 				error = sysctl_iflist_addr(w, ifa, &info);
364 				break;
365 			case NET_RT_OIFLIST:
366 			case NET_RT_OOIFLIST:
367 			case NET_RT_OOOIFLIST:
368 				MODULE_HOOK_CALL(rtsock_iflist_70_hook,
369 				    (w, ifa, &info), enosys(), error);
370 				break;
371 			default:
372 				error = EINVAL;
373 			}
374 
375 			_s = pserialize_read_enter();
376 			ifa_release(ifa, &_psref);
377 			if (error != 0) {
378 				pserialize_read_exit(_s);
379 				goto release_exit;
380 			}
381 		}
382 		pserialize_read_exit(_s);
383 		info.rti_info[RTAX_IFA] = info.rti_info[RTAX_NETMASK] =
384 		    info.rti_info[RTAX_BRD] = NULL;
385 
386 		s = pserialize_read_enter();
387 		if_release(ifp, &psref);
388 	}
389 	pserialize_read_exit(s);
390 	curlwp_bindx(bound);
391 
392 	return 0;
393 
394 release_exit:
395 	if_release(ifp, &psref);
396 	curlwp_bindx(bound);
397 	return error;
398 }
399 
400 static int
401 sysctl_rtable(SYSCTLFN_ARGS)
402 {
403 	void 	*where = oldp;
404 	size_t	*given = oldlenp;
405 	int	i, s, error = EINVAL;
406 	u_char  af;
407 	struct	rt_walkarg w;
408 
409 	if (namelen == 1 && name[0] == CTL_QUERY)
410 		return sysctl_query(SYSCTLFN_CALL(rnode));
411 
412 	if (newp)
413 		return EPERM;
414 	if (namelen != 3)
415 		return EINVAL;
416 	af = name[0];
417 	w.w_tmemneeded = 0;
418 	w.w_tmemsize = 0;
419 	w.w_tmem = NULL;
420 again:
421 	/* we may return here if a later [re]alloc of the t_mem buffer fails */
422 	if (w.w_tmemneeded) {
423 		w.w_tmem = kmem_zalloc(w.w_tmemneeded, KM_SLEEP);
424 		w.w_tmemsize = w.w_tmemneeded;
425 		w.w_tmemneeded = 0;
426 	}
427 	w.w_op = name[1];
428 	w.w_arg = name[2];
429 	w.w_given = *given;
430 	w.w_needed = 0 - w.w_given;
431 	w.w_where = where;
432 
433 	KERNEL_LOCK_UNLESS_NET_MPSAFE();
434 	s = splsoftnet();
435 	switch (w.w_op) {
436 
437 	case NET_RT_DUMP:
438 	case NET_RT_FLAGS:
439 #if defined(INET) || defined(INET6)
440 		/*
441 		 * take care of llinfo entries, the caller must
442 		 * specify an AF
443 		 */
444 		if (w.w_op == NET_RT_FLAGS &&
445 		    (w.w_arg == 0 || w.w_arg & RTF_LLDATA)) {
446 			if (af != 0)
447 				error = lltable_sysctl_dump(af, &w);
448 			else
449 				error = EINVAL;
450 			break;
451 		}
452 #endif
453 
454 		for (i = 1; i <= AF_MAX; i++) {
455 			if (af == 0 || af == i) {
456 				error = rt_walktree(i, sysctl_dumpentry, &w);
457 				if (error != 0)
458 					break;
459 #if defined(INET) || defined(INET6)
460 				/*
461 				 * Return ARP/NDP entries too for
462 				 * backward compatibility.
463 				 */
464 				error = lltable_sysctl_dump(i, &w);
465 				if (error != 0)
466 					break;
467 #endif
468 			}
469 		}
470 		break;
471 
472 	case NET_RT_OOOIFLIST:		/* compat_14 */
473 	case NET_RT_OOIFLIST:		/* compat_50 */
474 	case NET_RT_OIFLIST:		/* compat_70 */
475 	case NET_RT_IFLIST:		/* current */
476 		error = sysctl_iflist(af, &w, w.w_op);
477 		break;
478 	}
479 	splx(s);
480 	KERNEL_UNLOCK_UNLESS_NET_MPSAFE();
481 
482 	/* check to see if we couldn't allocate memory with NOWAIT */
483 	if (error == ENOBUFS && w.w_tmem == 0 && w.w_tmemneeded)
484 		goto again;
485 
486 	if (w.w_tmem)
487 		kmem_free(w.w_tmem, w.w_tmemsize);
488 	w.w_needed += w.w_given;
489 	if (where) {
490 		*given = (char *)w.w_where - (char *)where;
491 		if (*given < w.w_needed)
492 			return ENOMEM;
493 	} else {
494 		*given = (11 * w.w_needed) / 10;
495 	}
496 	return error;
497 }
498 
499 void
500 sysctl_net_route_setup(struct sysctllog **clog, int pf, const char *name)
501 {
502 	const struct sysctlnode *rnode = NULL;
503 
504 	sysctl_createv(clog, 0, NULL, &rnode,
505 		       CTLFLAG_PERMANENT,
506 		       CTLTYPE_NODE, name,
507 		       SYSCTL_DESCR("PF_ROUTE information"),
508 		       NULL, 0, NULL, 0,
509 		       CTL_NET, pf, CTL_EOL);
510 
511 	sysctl_createv(clog, 0, NULL, NULL,
512 		       CTLFLAG_PERMANENT,
513 		       CTLTYPE_NODE, "rtable",
514 		       SYSCTL_DESCR("Routing table information"),
515 		       sysctl_rtable, 0, NULL, 0,
516 		       CTL_NET, pf, 0 /* any protocol */, CTL_EOL);
517 
518 	sysctl_createv(clog, 0, &rnode, NULL,
519 		       CTLFLAG_PERMANENT,
520 		       CTLTYPE_STRUCT, "stats",
521 		       SYSCTL_DESCR("Routing statistics"),
522 		       NULL, 0, &rtstat, sizeof(rtstat),
523 		       CTL_CREATE, CTL_EOL);
524 }
525