xref: /original-bsd/sys/net/if.c (revision deff14a8) 
1 /*
2  * Copyright (c) 1980, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)if.c	8.4 (Berkeley) 07/01/94
8  */
9 
10 #include <sys/param.h>
11 #include <sys/mbuf.h>
12 #include <sys/systm.h>
13 #include <sys/proc.h>
14 #include <sys/socket.h>
15 #include <sys/socketvar.h>
16 #include <sys/protosw.h>
17 #include <sys/kernel.h>
18 #include <sys/ioctl.h>
19 
20 #include <net/if.h>
21 #include <net/if_dl.h>
22 #include <net/if_types.h>
23 
24 int	ifqmaxlen = IFQ_MAXLEN;
25 void	if_slowtimo __P((void *arg));
26 
27 /*
28  * Network interface utility routines.
29  *
30  * Routines with ifa_ifwith* names take sockaddr *'s as
31  * parameters.
32  */
33 void
34 ifinit()
35 {
36 	register struct ifnet *ifp;
37 
38 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
39 		if (ifp->if_snd.ifq_maxlen == 0)
40 			ifp->if_snd.ifq_maxlen = ifqmaxlen;
41 	if_slowtimo(0);
42 }
43 
44 #ifdef vax
45 /*
46  * Call each interface on a Unibus reset.
47  */
48 void
49 ifubareset(uban)
50 	int uban;
51 {
52 	register struct ifnet *ifp;
53 
54 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
55 		if (ifp->if_reset)
56 			(*ifp->if_reset)(ifp->if_unit, uban);
57 }
58 #endif
59 
60 int if_index = 0;
61 struct ifaddr **ifnet_addrs;
62 static char *sprint_d __P((u_int, char *, int));
63 
64 /*
65  * Attach an interface to the
66  * list of "active" interfaces.
67  */
68 void
69 if_attach(ifp)
70 	struct ifnet *ifp;
71 {
72 	unsigned socksize, ifasize;
73 	int namelen, unitlen, masklen, ether_output();
74 	char workbuf[12], *unitname;
75 	register struct ifnet **p = &ifnet;
76 	register struct sockaddr_dl *sdl;
77 	register struct ifaddr *ifa;
78 	static int if_indexlim = 8;
79 	extern void link_rtrequest();
80 
81 	while (*p)
82 		p = &((*p)->if_next);
83 	*p = ifp;
84 	ifp->if_index = ++if_index;
85 	if (ifnet_addrs == 0 || if_index >= if_indexlim) {
86 		unsigned n = (if_indexlim <<= 1) * sizeof(ifa);
87 		struct ifaddr **q = (struct ifaddr **)
88 					malloc(n, M_IFADDR, M_WAITOK);
89 		if (ifnet_addrs) {
90 			bcopy((caddr_t)ifnet_addrs, (caddr_t)q, n/2);
91 			free((caddr_t)ifnet_addrs, M_IFADDR);
92 		}
93 		ifnet_addrs = q;
94 	}
95 	/*
96 	 * create a Link Level name for this device
97 	 */
98 	unitname = sprint_d((u_int)ifp->if_unit, workbuf, sizeof(workbuf));
99 	namelen = strlen(ifp->if_name);
100 	unitlen = strlen(unitname);
101 #define _offsetof(t, m) ((int)((caddr_t)&((t *)0)->m))
102 	masklen = _offsetof(struct sockaddr_dl, sdl_data[0]) +
103 			       unitlen + namelen;
104 	socksize = masklen + ifp->if_addrlen;
105 #define ROUNDUP(a) (1 + (((a) - 1) | (sizeof(long) - 1)))
106 	socksize = ROUNDUP(socksize);
107 	if (socksize < sizeof(*sdl))
108 		socksize = sizeof(*sdl);
109 	ifasize = sizeof(*ifa) + 2 * socksize;
110 	if (ifa = (struct ifaddr *)malloc(ifasize, M_IFADDR, M_WAITOK)) {
111 		bzero((caddr_t)ifa, ifasize);
112 		sdl = (struct sockaddr_dl *)(ifa + 1);
113 		sdl->sdl_len = socksize;
114 		sdl->sdl_family = AF_LINK;
115 		bcopy(ifp->if_name, sdl->sdl_data, namelen);
116 		bcopy(unitname, namelen + (caddr_t)sdl->sdl_data, unitlen);
117 		sdl->sdl_nlen = (namelen += unitlen);
118 		sdl->sdl_index = ifp->if_index;
119 		sdl->sdl_type = ifp->if_type;
120 		ifnet_addrs[if_index - 1] = ifa;
121 		ifa->ifa_ifp = ifp;
122 		ifa->ifa_next = ifp->if_addrlist;
123 		ifa->ifa_rtrequest = link_rtrequest;
124 		ifp->if_addrlist = ifa;
125 		ifa->ifa_addr = (struct sockaddr *)sdl;
126 		sdl = (struct sockaddr_dl *)(socksize + (caddr_t)sdl);
127 		ifa->ifa_netmask = (struct sockaddr *)sdl;
128 		sdl->sdl_len = masklen;
129 		while (namelen != 0)
130 			sdl->sdl_data[--namelen] = 0xff;
131 	}
132 	/* XXX -- Temporary fix before changing 10 ethernet drivers */
133 	if (ifp->if_output == ether_output)
134 		ether_ifattach(ifp);
135 }
136 /*
137  * Locate an interface based on a complete address.
138  */
139 /*ARGSUSED*/
140 struct ifaddr *
141 ifa_ifwithaddr(addr)
142 	register struct sockaddr *addr;
143 {
144 	register struct ifnet *ifp;
145 	register struct ifaddr *ifa;
146 
147 #define	equal(a1, a2) \
148   (bcmp((caddr_t)(a1), (caddr_t)(a2), ((struct sockaddr *)(a1))->sa_len) == 0)
149 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
150 	    for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
151 		if (ifa->ifa_addr->sa_family != addr->sa_family)
152 			continue;
153 		if (equal(addr, ifa->ifa_addr))
154 			return (ifa);
155 		if ((ifp->if_flags & IFF_BROADCAST) && ifa->ifa_broadaddr &&
156 		    equal(ifa->ifa_broadaddr, addr))
157 			return (ifa);
158 	}
159 	return ((struct ifaddr *)0);
160 }
161 /*
162  * Locate the point to point interface with a given destination address.
163  */
164 /*ARGSUSED*/
165 struct ifaddr *
166 ifa_ifwithdstaddr(addr)
167 	register struct sockaddr *addr;
168 {
169 	register struct ifnet *ifp;
170 	register struct ifaddr *ifa;
171 
172 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
173 	    if (ifp->if_flags & IFF_POINTOPOINT)
174 		for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
175 			if (ifa->ifa_addr->sa_family != addr->sa_family ||
176 			    ifa->ifa_dstaddr == NULL)
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((caddr_t)ifa->ifa_netmask,
218 		    (caddr_t)ifa_maybe->ifa_netmask))
219 			ifa_maybe = ifa;
220 	    }
221 	return (ifa_maybe);
222 }
223 
224 /*
225  * Find an interface using a specific address family
226  */
227 struct ifaddr *
228 ifa_ifwithaf(af)
229 	register int af;
230 {
231 	register struct ifnet *ifp;
232 	register struct ifaddr *ifa;
233 
234 	for (ifp = ifnet; ifp; ifp = ifp->if_next)
235 	    for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
236 		if (ifa->ifa_addr->sa_family == af)
237 			return (ifa);
238 	return ((struct ifaddr *)0);
239 }
240 
241 /*
242  * Find an interface address specific to an interface best matching
243  * a given address.
244  */
245 struct ifaddr *
246 ifaof_ifpforaddr(addr, ifp)
247 	struct sockaddr *addr;
248 	register struct ifnet *ifp;
249 {
250 	register struct ifaddr *ifa;
251 	register char *cp, *cp2, *cp3;
252 	register char *cplim;
253 	struct ifaddr *ifa_maybe = 0;
254 	u_int af = addr->sa_family;
255 
256 	if (af >= AF_MAX)
257 		return (0);
258 	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next) {
259 		if (ifa->ifa_addr->sa_family != af)
260 			continue;
261 		ifa_maybe = ifa;
262 		if (ifa->ifa_netmask == 0) {
263 			if (equal(addr, ifa->ifa_addr) ||
264 			    (ifa->ifa_dstaddr && equal(addr, ifa->ifa_dstaddr)))
265 				return (ifa);
266 			continue;
267 		}
268 		cp = addr->sa_data;
269 		cp2 = ifa->ifa_addr->sa_data;
270 		cp3 = ifa->ifa_netmask->sa_data;
271 		cplim = ifa->ifa_netmask->sa_len + (char *)ifa->ifa_netmask;
272 		for (; cp3 < cplim; cp3++)
273 			if ((*cp++ ^ *cp2++) & *cp3)
274 				break;
275 		if (cp3 == cplim)
276 			return (ifa);
277 	}
278 	return (ifa_maybe);
279 }
280 
281 #include <net/route.h>
282 
283 /*
284  * Default action when installing a route with a Link Level gateway.
285  * Lookup an appropriate real ifa to point to.
286  * This should be moved to /sys/net/link.c eventually.
287  */
288 void
289 link_rtrequest(cmd, rt, sa)
290 	int cmd;
291 	register struct rtentry *rt;
292 	struct sockaddr *sa;
293 {
294 	register struct ifaddr *ifa;
295 	struct sockaddr *dst;
296 	struct ifnet *ifp;
297 
298 	if (cmd != RTM_ADD || ((ifa = rt->rt_ifa) == 0) ||
299 	    ((ifp = ifa->ifa_ifp) == 0) || ((dst = rt_key(rt)) == 0))
300 		return;
301 	if (ifa = ifaof_ifpforaddr(dst, ifp)) {
302 		IFAFREE(rt->rt_ifa);
303 		rt->rt_ifa = ifa;
304 		ifa->ifa_refcnt++;
305 		if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest)
306 			ifa->ifa_rtrequest(cmd, rt, sa);
307 	}
308 }
309 
310 /*
311  * Mark an interface down and notify protocols of
312  * the transition.
313  * NOTE: must be called at splnet or eqivalent.
314  */
315 void
316 if_down(ifp)
317 	register struct ifnet *ifp;
318 {
319 	register struct ifaddr *ifa;
320 
321 	ifp->if_flags &= ~IFF_UP;
322 	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
323 		pfctlinput(PRC_IFDOWN, ifa->ifa_addr);
324 	if_qflush(&ifp->if_snd);
325 	rt_ifmsg(ifp);
326 }
327 
328 /*
329  * Mark an interface up and notify protocols of
330  * the transition.
331  * NOTE: must be called at splnet or eqivalent.
332  */
333 void
334 if_up(ifp)
335 	register struct ifnet *ifp;
336 {
337 	register struct ifaddr *ifa;
338 
339 	ifp->if_flags |= IFF_UP;
340 #ifdef notyet
341 	/* this has no effect on IP, and will kill all iso connections XXX */
342 	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
343 		pfctlinput(PRC_IFUP, ifa->ifa_addr);
344 #endif
345 	rt_ifmsg(ifp);
346 }
347 
348 /*
349  * Flush an interface queue.
350  */
351 void
352 if_qflush(ifq)
353 	register struct ifqueue *ifq;
354 {
355 	register struct mbuf *m, *n;
356 
357 	n = ifq->ifq_head;
358 	while (m = n) {
359 		n = m->m_act;
360 		m_freem(m);
361 	}
362 	ifq->ifq_head = 0;
363 	ifq->ifq_tail = 0;
364 	ifq->ifq_len = 0;
365 }
366 
367 /*
368  * Handle interface watchdog timer routines.  Called
369  * from softclock, we decrement timers (if set) and
370  * call the appropriate interface routine on expiration.
371  */
372 void
373 if_slowtimo(arg)
374 	void *arg;
375 {
376 	register struct ifnet *ifp;
377 	int s = splimp();
378 
379 	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
380 		if (ifp->if_timer == 0 || --ifp->if_timer)
381 			continue;
382 		if (ifp->if_watchdog)
383 			(*ifp->if_watchdog)(ifp->if_unit);
384 	}
385 	splx(s);
386 	timeout(if_slowtimo, (void *)0, hz / IFNET_SLOWHZ);
387 }
388 
389 /*
390  * Map interface name to
391  * interface structure pointer.
392  */
393 struct ifnet *
394 ifunit(name)
395 	register char *name;
396 {
397 	register char *cp;
398 	register struct ifnet *ifp;
399 	int unit;
400 	unsigned len;
401 	char *ep, c;
402 
403 	for (cp = name; cp < name + IFNAMSIZ && *cp; cp++)
404 		if (*cp >= '0' && *cp <= '9')
405 			break;
406 	if (*cp == '\0' || cp == name + IFNAMSIZ)
407 		return ((struct ifnet *)0);
408 	/*
409 	 * Save first char of unit, and pointer to it,
410 	 * so we can put a null there to avoid matching
411 	 * initial substrings of interface names.
412 	 */
413 	len = cp - name + 1;
414 	c = *cp;
415 	ep = cp;
416 	for (unit = 0; *cp >= '0' && *cp <= '9'; )
417 		unit = unit * 10 + *cp++ - '0';
418 	*ep = 0;
419 	for (ifp = ifnet; ifp; ifp = ifp->if_next) {
420 		if (bcmp(ifp->if_name, name, len))
421 			continue;
422 		if (unit == ifp->if_unit)
423 			break;
424 	}
425 	*ep = c;
426 	return (ifp);
427 }
428 
429 /*
430  * Interface ioctls.
431  */
432 int
433 ifioctl(so, cmd, data, p)
434 	struct socket *so;
435 	int cmd;
436 	caddr_t data;
437 	struct proc *p;
438 {
439 	register struct ifnet *ifp;
440 	register struct ifreq *ifr;
441 	int error;
442 
443 	switch (cmd) {
444 
445 	case SIOCGIFCONF:
446 	case OSIOCGIFCONF:
447 		return (ifconf(cmd, data));
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 	case SIOCADDMULTI:
489 	case SIOCDELMULTI:
490 		if (error = suser(p->p_ucred, &p->p_acflag))
491 			return (error);
492 		if (ifp->if_ioctl == NULL)
493 			return (EOPNOTSUPP);
494 		return ((*ifp->if_ioctl)(ifp, cmd, data));
495 
496 	default:
497 		if (so->so_proto == 0)
498 			return (EOPNOTSUPP);
499 #ifndef COMPAT_43
500 		return ((*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
501 			cmd, data, ifp));
502 #else
503 	    {
504 		int ocmd = cmd;
505 
506 		switch (cmd) {
507 
508 		case SIOCSIFDSTADDR:
509 		case SIOCSIFADDR:
510 		case SIOCSIFBRDADDR:
511 		case SIOCSIFNETMASK:
512 #if BYTE_ORDER != BIG_ENDIAN
513 			if (ifr->ifr_addr.sa_family == 0 &&
514 			    ifr->ifr_addr.sa_len < 16) {
515 				ifr->ifr_addr.sa_family = ifr->ifr_addr.sa_len;
516 				ifr->ifr_addr.sa_len = 16;
517 			}
518 #else
519 			if (ifr->ifr_addr.sa_len == 0)
520 				ifr->ifr_addr.sa_len = 16;
521 #endif
522 			break;
523 
524 		case OSIOCGIFADDR:
525 			cmd = SIOCGIFADDR;
526 			break;
527 
528 		case OSIOCGIFDSTADDR:
529 			cmd = SIOCGIFDSTADDR;
530 			break;
531 
532 		case OSIOCGIFBRDADDR:
533 			cmd = SIOCGIFBRDADDR;
534 			break;
535 
536 		case OSIOCGIFNETMASK:
537 			cmd = SIOCGIFNETMASK;
538 		}
539 		error =  ((*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
540 							    cmd, data, ifp));
541 		switch (ocmd) {
542 
543 		case OSIOCGIFADDR:
544 		case OSIOCGIFDSTADDR:
545 		case OSIOCGIFBRDADDR:
546 		case OSIOCGIFNETMASK:
547 			*(u_short *)&ifr->ifr_addr = ifr->ifr_addr.sa_family;
548 		}
549 		return (error);
550 
551 	    }
552 #endif
553 	}
554 	return (0);
555 }
556 
557 /*
558  * Return interface configuration
559  * of system.  List may be used
560  * in later ioctl's (above) to get
561  * other information.
562  */
563 /*ARGSUSED*/
564 int
565 ifconf(cmd, data)
566 	int cmd;
567 	caddr_t data;
568 {
569 	register struct ifconf *ifc = (struct ifconf *)data;
570 	register struct ifnet *ifp = ifnet;
571 	register struct ifaddr *ifa;
572 	register char *cp, *ep;
573 	struct ifreq ifr, *ifrp;
574 	int space = ifc->ifc_len, error = 0;
575 
576 	ifrp = ifc->ifc_req;
577 	ep = ifr.ifr_name + sizeof (ifr.ifr_name) - 2;
578 	for (; space > sizeof (ifr) && ifp; ifp = ifp->if_next) {
579 		strncpy(ifr.ifr_name, ifp->if_name, sizeof (ifr.ifr_name) - 2);
580 		for (cp = ifr.ifr_name; cp < ep && *cp; cp++)
581 			continue;
582 		*cp++ = '0' + ifp->if_unit; *cp = '\0';
583 		if ((ifa = ifp->if_addrlist) == 0) {
584 			bzero((caddr_t)&ifr.ifr_addr, sizeof(ifr.ifr_addr));
585 			error = copyout((caddr_t)&ifr, (caddr_t)ifrp,
586 			    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