xref: /csrg-svn/sys/net/if.c (revision 54718)
1 /*
2  * Copyright (c) 1980, 1986 Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)if.c	7.20 (Berkeley) 07/06/92
8  */
9 
10 #include "param.h"
11 #include "mbuf.h"
12 #include "systm.h"
13 #include "proc.h"
14 #include "socket.h"
15 #include "socketvar.h"
16 #include "protosw.h"
17 #include "kernel.h"
18 #include "ioctl.h"
19 
20 #include "if.h"
21 #include "af.h"
22 #include "if_dl.h"
23 #include "if_types.h"
24 
25 #include "ether.h"
26 
27 int	ifqmaxlen = IFQ_MAXLEN;
28 
29 /*
30  * Network interface utility routines.
31  *
32  * Routines with ifa_ifwith* names take sockaddr *'s as
33  * parameters.
34  */
35 
36 ifinit()
37 {
38 	register struct ifnet *ifp;
39 
40 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
41 		if (ifp->if_snd.ifq_maxlen == 0)
42 			ifp->if_snd.ifq_maxlen = ifqmaxlen;
43 	if_slowtimo();
44 }
45 
46 #ifdef vax
47 /*
48  * Call each interface on a Unibus reset.
49  */
50 ifubareset(uban)
51 	int uban;
52 {
53 	register struct ifnet *ifp;
54 
55 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
56 		if (ifp->if_reset)
57 			(*ifp->if_reset)(ifp->if_unit, uban);
58 }
59 #endif
60 
61 int if_index = 0;
62 struct ifaddr **ifnet_addrs;
63 static char *sprint_d();
64 
65 /*
66  * Attach an interface to the
67  * list of "active" interfaces.
68  */
69 void
70 if_attach(ifp)
71 	struct ifnet *ifp;
72 {
73 	unsigned socksize, ifasize;
74 	int namelen, unitlen, masklen, ether_output();
75 	char workbuf[12], *unitname;
76 	register struct ifnet **p = &ifnet;
77 	register struct sockaddr_dl *sdl;
78 	register struct ifaddr *ifa;
79 	static int if_indexlim = 8;
80 	extern void link_rtrequest();
81 
82 	while (*p)
83 		p = &((*p)->if_next);
84 	*p = ifp;
85 	ifp->if_index = ++if_index;
86 	if (ifnet_addrs == 0 || if_index >= if_indexlim) {
87 		unsigned n = (if_indexlim <<= 1) * sizeof(ifa);
88 		struct ifaddr **q = (struct ifaddr **)
89 					malloc(n, M_IFADDR, M_WAITOK);
90 		if (ifnet_addrs) {
91 			bcopy((caddr_t)ifnet_addrs, (caddr_t)q, n/2);
92 			free((caddr_t)ifnet_addrs, M_IFADDR);
93 		}
94 		ifnet_addrs = q;
95 	}
96 	/*
97 	 * create a Link Level name for this device
98 	 */
99 	unitname = sprint_d((u_int)ifp->if_unit, workbuf, sizeof(workbuf));
100 	namelen = strlen(ifp->if_name);
101 	unitlen = strlen(unitname);
102 #define _offsetof(t, m) ((int)((caddr_t)&((t *)0)->m))
103 	masklen = _offsetof(struct sockaddr_dl, sdl_data[0]) +
104 			       unitlen + namelen;
105 	socksize = masklen + ifp->if_addrlen;
106 #define ROUNDUP(a) (1 + (((a) - 1) | (sizeof(long) - 1)))
107 	socksize = ROUNDUP(socksize);
108 	if (socksize < sizeof(*sdl))
109 		socksize = sizeof(*sdl);
110 	ifasize = sizeof(*ifa) + 2 * socksize;
111 	if (ifa = (struct ifaddr *)malloc(ifasize, M_IFADDR, M_WAITOK)) {
112 		bzero((caddr_t)ifa, ifasize);
113 		sdl = (struct sockaddr_dl *)(ifa + 1);
114 		sdl->sdl_len = socksize;
115 		sdl->sdl_family = AF_LINK;
116 		bcopy(ifp->if_name, sdl->sdl_data, namelen);
117 		bcopy(unitname, namelen + (caddr_t)sdl->sdl_data, unitlen);
118 		sdl->sdl_nlen = (namelen += unitlen);
119 		sdl->sdl_index = ifp->if_index;
120 		sdl->sdl_type = ifp->if_type;
121 		ifnet_addrs[if_index - 1] = ifa;
122 		ifa->ifa_ifp = ifp;
123 		ifa->ifa_next = ifp->if_addrlist;
124 		ifa->ifa_rtrequest = link_rtrequest;
125 		ifp->if_addrlist = ifa;
126 		ifa->ifa_addr = (struct sockaddr *)sdl;
127 		sdl = (struct sockaddr_dl *)(socksize + (caddr_t)sdl);
128 		ifa->ifa_netmask = (struct sockaddr *)sdl;
129 		sdl->sdl_len = masklen;
130 		while (namelen != 0)
131 			sdl->sdl_data[--namelen] = 0xff;
132 	}
133 	/* XXX -- Temporary fix before changing 10 ethernet drivers */
134 	if (ifp->if_output == ether_output)
135 		ether_ifattach(ifp);
136 }
137 /*
138  * Locate an interface based on a complete address.
139  */
140 /*ARGSUSED*/
141 struct ifaddr *
142 ifa_ifwithaddr(addr)
143 	register struct sockaddr *addr;
144 {
145 	register struct ifnet *ifp;
146 	register struct ifaddr *ifa;
147 
148 #define	equal(a1, a2) \
149   (bcmp((caddr_t)(a1), (caddr_t)(a2), ((struct sockaddr *)(a1))->sa_len) == 0)
150 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
151 	    for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
152 		if (ifa->ifa_addr->sa_family != addr->sa_family)
153 			continue;
154 		if (equal(addr, ifa->ifa_addr))
155 			return (ifa);
156 		if ((ifp->if_flags & IFF_BROADCAST) && ifa->ifa_broadaddr &&
157 		    equal(ifa->ifa_broadaddr, addr))
158 			return (ifa);
159 	}
160 	return ((struct ifaddr *)0);
161 }
162 /*
163  * Locate the point to point interface with a given destination address.
164  */
165 /*ARGSUSED*/
166 struct ifaddr *
167 ifa_ifwithdstaddr(addr)
168 	register struct sockaddr *addr;
169 {
170 	register struct ifnet *ifp;
171 	register struct ifaddr *ifa;
172 
173 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
174 	    if (ifp->if_flags & IFF_POINTOPOINT)
175 		for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
176 			if (ifa->ifa_addr->sa_family != addr->sa_family)
177 				continue;
178 			if (equal(addr, ifa->ifa_dstaddr))
179 				return (ifa);
180 	}
181 	return ((struct ifaddr *)0);
182 }
183 
184 /*
185  * Find an interface on a specific network.  If many, choice
186  * is most specific found.
187  */
188 struct ifaddr *
189 ifa_ifwithnet(addr)
190 	struct sockaddr *addr;
191 {
192 	register struct ifnet *ifp;
193 	register struct ifaddr *ifa;
194 	struct ifaddr *ifa_maybe = (struct ifaddr *) 0;
195 	u_int af = addr->sa_family;
196 	char *addr_data = addr->sa_data, *cplim;
197 
198 	if (af == AF_LINK) {
199 	    register struct sockaddr_dl *sdl = (struct sockaddr_dl *)addr;
200 	    if (sdl->sdl_index && sdl->sdl_index <= if_index)
201 		return (ifnet_addrs[sdl->sdl_index - 1]);
202 	}
203 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
204 	    for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
205 		register char *cp, *cp2, *cp3;
206 
207 		if (ifa->ifa_addr->sa_family != af || ifa->ifa_netmask == 0)
208 			next: continue;
209 		cp = addr_data;
210 		cp2 = ifa->ifa_addr->sa_data;
211 		cp3 = ifa->ifa_netmask->sa_data;
212 		cplim = ifa->ifa_netmask->sa_len + (char *)ifa->ifa_netmask;
213 		while (cp3 < cplim)
214 			if ((*cp++ ^ *cp2++) & *cp3++)
215 				goto next;
216 		if (ifa_maybe == 0 ||
217 		    rn_refines(ifa->ifa_netmask, ifa_maybe->ifa_netmask))
218 			ifa_maybe = ifa;
219 	    }
220 	return (ifa_maybe);
221 }
222 
223 /*
224  * Find an interface using a specific address family
225  */
226 struct ifaddr *
227 ifa_ifwithaf(af)
228 	register int af;
229 {
230 	register struct ifnet *ifp;
231 	register struct ifaddr *ifa;
232 
233 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
234 	    for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
235 		if (ifa->ifa_addr->sa_family == af)
236 			return (ifa);
237 	return ((struct ifaddr *)0);
238 }
239 
240 /*
241  * Find an interface address specific to an interface best matching
242  * a given address.
243  */
244 struct ifaddr *
245 ifaof_ifpforaddr(addr, ifp)
246 	struct sockaddr *addr;
247 	register struct ifnet *ifp;
248 {
249 	register struct ifaddr *ifa;
250 	register char *cp, *cp2, *cp3;
251 	register char *cplim;
252 	struct ifaddr *ifa_maybe = 0;
253 	u_int af = addr->sa_family;
254 
255 	if (af >= AF_MAX)
256 		return (0);
257 	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
258 		if (ifa->ifa_addr->sa_family != af)
259 			continue;
260 		ifa_maybe = ifa;
261 		if (ifa->ifa_netmask == 0) {
262 			if (equal(addr, ifa->ifa_addr) ||
263 			    (ifa->ifa_dstaddr && equal(addr, ifa->ifa_dstaddr)))
264 				return (ifa);
265 			continue;
266 		}
267 		cp = addr->sa_data;
268 		cp2 = ifa->ifa_addr->sa_data;
269 		cp3 = ifa->ifa_netmask->sa_data;
270 		cplim = ifa->ifa_netmask->sa_len + (char *)ifa->ifa_netmask;
271 		for (; cp3 < cplim; cp3++)
272 			if ((*cp++ ^ *cp2++) & *cp3)
273 				break;
274 		if (cp3 == cplim)
275 			return (ifa);
276 	}
277 	return (ifa_maybe);
278 }
279 #include "route.h"
280 /*
281  * Default action when installing a route with a Link Level gateway.
282  * Lookup an appropriate real ifa to point to.
283  * This should be moved to /sys/net/link.c eventually.
284  */
285 void
286 link_rtrequest(cmd, rt, sa)
287 	int cmd;
288 	register struct rtentry *rt;
289 	struct sockaddr *sa;
290 {
291 	register struct ifaddr *ifa;
292 	struct sockaddr *dst;
293 	struct ifnet *ifp, *oldifnet = ifnet;
294 
295 	if (cmd != RTM_ADD || ((ifa = rt->rt_ifa) == 0) ||
296 	    ((ifp = ifa->ifa_ifp) == 0) || ((dst = rt_key(rt)) == 0))
297 		return;
298 	if (ifa = ifaof_ifpforaddr(dst, ifp)) {
299 		rt->rt_ifa = ifa;
300 		if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest)
301 			ifa->ifa_rtrequest(cmd, rt, sa);
302 	}
303 }
304 
305 /*
306  * Mark an interface down and notify protocols of
307  * the transition.
308  * NOTE: must be called at splnet or eqivalent.
309  */
310 if_down(ifp)
311 	register struct ifnet *ifp;
312 {
313 	register struct ifaddr *ifa;
314 
315 	ifp->if_flags &= ~IFF_UP;
316 	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
317 		pfctlinput(PRC_IFDOWN, ifa->ifa_addr);
318 	if_qflush(&ifp->if_snd);
319 	rt_ifmsg(ifp);
320 }
321 
322 /*
323  * Mark an interface up and notify protocols of
324  * the transition.
325  * NOTE: must be called at splnet or eqivalent.
326  */
327 if_up(ifp)
328 	register struct ifnet *ifp;
329 {
330 	register struct ifaddr *ifa;
331 
332 	ifp->if_flags |= IFF_UP;
333 #ifdef notyet
334 	/* this has no effect on IP, and will kill all iso connections XXX */
335 	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
336 		pfctlinput(PRC_IFUP, ifa->ifa_addr);
337 #endif notyet
338 	rt_ifmsg(ifp);
339 }
340 
341 /*
342  * Flush an interface queue.
343  */
344 if_qflush(ifq)
345 	register struct ifqueue *ifq;
346 {
347 	register struct mbuf *m, *n;
348 
349 	n = ifq->ifq_head;
350 	while (m = n) {
351 		n = m->m_act;
352 		m_freem(m);
353 	}
354 	ifq->ifq_head = 0;
355 	ifq->ifq_tail = 0;
356 	ifq->ifq_len = 0;
357 }
358 
359 /*
360  * Handle interface watchdog timer routines.  Called
361  * from softclock, we decrement timers (if set) and
362  * call the appropriate interface routine on expiration.
363  */
364 if_slowtimo()
365 {
366 	register struct ifnet *ifp;
367 	int s = splimp();
368 
369 	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
370 		if (ifp->if_timer == 0 || --ifp->if_timer)
371 			continue;
372 		if (ifp->if_watchdog)
373 			(*ifp->if_watchdog)(ifp->if_unit);
374 	}
375 	splx(s);
376 	timeout(if_slowtimo, (caddr_t)0, hz / IFNET_SLOWHZ);
377 }
378 
379 /*
380  * Map interface name to
381  * interface structure pointer.
382  */
383 struct ifnet *
384 ifunit(name)
385 	register char *name;
386 {
387 	register char *cp;
388 	register struct ifnet *ifp;
389 	int unit;
390 	unsigned len;
391 	char *ep, c;
392 
393 	for (cp = name; cp < name + IFNAMSIZ && *cp; cp++)
394 		if (*cp >= '0' && *cp <= '9')
395 			break;
396 	if (*cp == '\0' || cp == name + IFNAMSIZ)
397 		return ((struct ifnet *)0);
398 	/*
399 	 * Save first char of unit, and pointer to it,
400 	 * so we can put a null there to avoid matching
401 	 * initial substrings of interface names.
402 	 */
403 	len = cp - name + 1;
404 	c = *cp;
405 	ep = cp;
406 	for (unit = 0; *cp >= '0' && *cp <= '9'; )
407 		unit = unit * 10 + *cp++ - '0';
408 	*ep = 0;
409 	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
410 		if (bcmp(ifp->if_name, name, len))
411 			continue;
412 		if (unit == ifp->if_unit)
413 			break;
414 	}
415 	*ep = c;
416 	return (ifp);
417 }
418 
419 /*
420  * Interface ioctls.
421  */
422 ifioctl(so, cmd, data, p)
423 	struct socket *so;
424 	int cmd;
425 	caddr_t data;
426 	struct proc *p;
427 {
428 	register struct ifnet *ifp;
429 	register struct ifreq *ifr;
430 	int error;
431 
432 	switch (cmd) {
433 
434 	case SIOCGIFCONF:
435 	case OSIOCGIFCONF:
436 		return (ifconf(cmd, data));
437 
438 #if defined(INET) && NETHER > 0
439 	case SIOCSARP:
440 	case SIOCDARP:
441 		if (error = suser(p->p_ucred, &p->p_acflag))
442 			return (error);
443 		/* FALL THROUGH */
444 	case SIOCGARP:
445 	case OSIOCGARP:
446 		return (arpioctl(cmd, data));
447 #endif
448 	}
449 	ifr = (struct ifreq *)data;
450 	ifp = ifunit(ifr->ifr_name);
451 	if (ifp == 0)
452 		return (ENXIO);
453 	switch (cmd) {
454 
455 	case SIOCGIFFLAGS:
456 		ifr->ifr_flags = ifp->if_flags;
457 		break;
458 
459 	case SIOCGIFMETRIC:
460 		ifr->ifr_metric = ifp->if_metric;
461 		break;
462 
463 	case SIOCSIFFLAGS:
464 		if (error = suser(p->p_ucred, &p->p_acflag))
465 			return (error);
466 		if (ifp->if_flags & IFF_UP && (ifr->ifr_flags & IFF_UP) == 0) {
467 			int s = splimp();
468 			if_down(ifp);
469 			splx(s);
470 		}
471 		if (ifr->ifr_flags & IFF_UP && (ifp->if_flags & IFF_UP) == 0) {
472 			int s = splimp();
473 			if_up(ifp);
474 			splx(s);
475 		}
476 		ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) |
477 			(ifr->ifr_flags &~ IFF_CANTCHANGE);
478 		if (ifp->if_ioctl)
479 			(void) (*ifp->if_ioctl)(ifp, cmd, data);
480 		break;
481 
482 	case SIOCSIFMETRIC:
483 		if (error = suser(p->p_ucred, &p->p_acflag))
484 			return (error);
485 		ifp->if_metric = ifr->ifr_metric;
486 		break;
487 
488 #ifdef MULTICAST
489 	case SIOCADDMULTI:
490 	case SIOCDELMULTI:
491 		if (error = suser(p->p_ucred, &p->p_acflag))
492 			return (error);
493 		if (ifp->if_ioctl)
494 			return (EOPNOTSUPP);
495 		return ((*ifp->if_ioctl)(ifp, cmd, data));
496 #endif
497 
498 	default:
499 		if (so->so_proto == 0)
500 			return (EOPNOTSUPP);
501 #ifndef COMPAT_43
502 		return ((*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
503 			cmd, data, ifp));
504 #else
505 	    {
506 		int ocmd = cmd;
507 
508 		switch (cmd) {
509 
510 		case SIOCSIFDSTADDR:
511 		case SIOCSIFADDR:
512 		case SIOCSIFBRDADDR:
513 		case SIOCSIFNETMASK:
514 #if BYTE_ORDER != BIG_ENDIAN
515 			if (ifr->ifr_addr.sa_family == 0 &&
516 			    ifr->ifr_addr.sa_len < 16) {
517 				ifr->ifr_addr.sa_family = ifr->ifr_addr.sa_len;
518 				ifr->ifr_addr.sa_len = 16;
519 			}
520 #else
521 			if (ifr->ifr_addr.sa_len == 0)
522 				ifr->ifr_addr.sa_len = 16;
523 #endif
524 			break;
525 
526 		case OSIOCGIFADDR:
527 			cmd = SIOCGIFADDR;
528 			break;
529 
530 		case OSIOCGIFDSTADDR:
531 			cmd = SIOCGIFDSTADDR;
532 			break;
533 
534 		case OSIOCGIFBRDADDR:
535 			cmd = SIOCGIFBRDADDR;
536 			break;
537 
538 		case OSIOCGIFNETMASK:
539 			cmd = SIOCGIFNETMASK;
540 		}
541 		error =  ((*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
542 							    cmd, data, ifp));
543 		switch (ocmd) {
544 
545 		case OSIOCGIFADDR:
546 		case OSIOCGIFDSTADDR:
547 		case OSIOCGIFBRDADDR:
548 		case OSIOCGIFNETMASK:
549 			*(u_short *)&ifr->ifr_addr = ifr->ifr_addr.sa_family;
550 		}
551 		return (error);
552 
553 	    }
554 #endif
555 	}
556 	return (0);
557 }
558 
559 /*
560  * Return interface configuration
561  * of system.  List may be used
562  * in later ioctl's (above) to get
563  * other information.
564  */
565 /*ARGSUSED*/
566 ifconf(cmd, data)
567 	int cmd;
568 	caddr_t data;
569 {
570 	register struct ifconf *ifc = (struct ifconf *)data;
571 	register struct ifnet *ifp = ifnet;
572 	register struct ifaddr *ifa;
573 	register char *cp, *ep;
574 	struct ifreq ifr, *ifrp;
575 	int space = ifc->ifc_len, error = 0;
576 
577 	ifrp = ifc->ifc_req;
578 	ep = ifr.ifr_name + sizeof (ifr.ifr_name) - 2;
579 	for (; space > sizeof (ifr) && ifp; ifp = ifp->if_next) {
580 		bcopy(ifp->if_name, ifr.ifr_name, sizeof (ifr.ifr_name) - 2);
581 		for (cp = ifr.ifr_name; cp < ep && *cp; cp++)
582 			continue;
583 		*cp++ = '0' + ifp->if_unit; *cp = '\0';
584 		if ((ifa = ifp->if_addrlist) == 0) {
585 			bzero((caddr_t)&ifr.ifr_addr, sizeof(ifr.ifr_addr));
586 			error = copyout((caddr_t)&ifr, (caddr_t)ifrp, sizeof (ifr));
587 			if (error)
588 				break;
589 			space -= sizeof (ifr), ifrp++;
590 		} else
591 		    for ( ; space > sizeof (ifr) && ifa; ifa = ifa->ifa_next) {
592 			register struct sockaddr *sa = ifa->ifa_addr;
593 #ifdef COMPAT_43
594 			if (cmd == OSIOCGIFCONF) {
595 				struct osockaddr *osa =
596 					 (struct osockaddr *)&ifr.ifr_addr;
597 				ifr.ifr_addr = *sa;
598 				osa->sa_family = sa->sa_family;
599 				error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
600 						sizeof (ifr));
601 				ifrp++;
602 			} else
603 #endif
604 			if (sa->sa_len <= sizeof(*sa)) {
605 				ifr.ifr_addr = *sa;
606 				error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
607 						sizeof (ifr));
608 				ifrp++;
609 			} else {
610 				space -= sa->sa_len - sizeof(*sa);
611 				if (space < sizeof (ifr))
612 					break;
613 				error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
614 						sizeof (ifr.ifr_name));
615 				if (error == 0)
616 				    error = copyout((caddr_t)sa,
617 				      (caddr_t)&ifrp->ifr_addr, sa->sa_len);
618 				ifrp = (struct ifreq *)
619 					(sa->sa_len + (caddr_t)&ifrp->ifr_addr);
620 			}
621 			if (error)
622 				break;
623 			space -= sizeof (ifr);
624 		}
625 	}
626 	ifc->ifc_len -= space;
627 	return (error);
628 }
629 
630 static char *
631 sprint_d(n, buf, buflen)
632 	u_int n;
633 	char *buf;
634 	int buflen;
635 {
636 	register char *cp = buf + buflen - 1;
637 
638 	*cp = 0;
639 	do {
640 		cp--;
641 		*cp = "0123456789"[n % 10];
642 		n /= 10;
643 	} while (n != 0);
644 	return (cp);
645 }
646