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if_loop.c revision 1.41 
      1 /*	$NetBSD: if_loop.c,v 1.41 2002/09/26 16:07:03 darrenr 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) 1982, 1986, 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. All advertising materials mentioning features or use of this software
     45  *    must display the following acknowledgement:
     46  *	This product includes software developed by the University of
     47  *	California, Berkeley and its contributors.
     48  * 4. Neither the name of the University nor the names of its contributors
     49  *    may be used to endorse or promote products derived from this software
     50  *    without specific prior written permission.
     51  *
     52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     62  * SUCH DAMAGE.
     63  *
     64  *	@(#)if_loop.c	8.2 (Berkeley) 1/9/95
     65  */
     66 
     67 /*
     68  * Loopback interface driver for protocol testing and timing.
     69  */
     70 
     71 #include <sys/cdefs.h>
     72 __KERNEL_RCSID(0, "$NetBSD: if_loop.c,v 1.41 2002/09/26 16:07:03 darrenr Exp $");
     73 
     74 #include "opt_inet.h"
     75 #include "opt_atalk.h"
     76 #include "opt_iso.h"
     77 #include "opt_ns.h"
     78 
     79 #include "bpfilter.h"
     80 #include "loop.h"
     81 
     82 #include <sys/param.h>
     83 #include <sys/systm.h>
     84 #include <sys/kernel.h>
     85 #include <sys/mbuf.h>
     86 #include <sys/socket.h>
     87 #include <sys/errno.h>
     88 #include <sys/ioctl.h>
     89 #include <sys/time.h>
     90 
     91 #include <machine/cpu.h>
     92 
     93 #include <net/if.h>
     94 #include <net/if_types.h>
     95 #include <net/netisr.h>
     96 #include <net/route.h>
     97 
     98 #ifdef	INET
     99 #include <netinet/in.h>
    100 #include <netinet/in_systm.h>
    101 #include <netinet/in_var.h>
    102 #include <netinet/ip.h>
    103 #endif
    104 
    105 #ifdef INET6
    106 #ifndef INET
    107 #include <netinet/in.h>
    108 #endif
    109 #include <netinet6/in6_var.h>
    110 #include <netinet/ip6.h>
    111 #endif
    112 
    113 #ifdef NS
    114 #include <netns/ns.h>
    115 #include <netns/ns_if.h>
    116 #endif
    117 
    118 #ifdef IPX
    119 #include <netipx/ipx.h>
    120 #include <netipx/ipx_if.h>
    121 #endif
    122 
    123 #ifdef ISO
    124 #include <netiso/iso.h>
    125 #include <netiso/iso_var.h>
    126 #endif
    127 
    128 #ifdef NETATALK
    129 #include <netatalk/at.h>
    130 #include <netatalk/at_var.h>
    131 #endif
    132 
    133 #if NBPFILTER > 0
    134 #include <net/bpf.h>
    135 #endif
    136 
    137 #if defined(LARGE_LOMTU)
    138 #define LOMTU	(131072 +  MHLEN + MLEN)
    139 #else
    140 #define	LOMTU	(32768 +  MHLEN + MLEN)
    141 #endif
    142 
    143 struct	ifnet loif[NLOOP];
    144 
    145 #ifdef ALTQ
    146 void	lostart(struct ifnet *);
    147 #endif
    148 
    149 void
    150 loopattach(n)
    151 	int n;
    152 {
    153 	int i;
    154 	struct ifnet *ifp;
    155 
    156 	for (i = 0; i < NLOOP; i++) {
    157 		ifp = &loif[i];
    158 		sprintf(ifp->if_xname, "lo%d", i);
    159 		ifp->if_softc = NULL;
    160 		ifp->if_mtu = LOMTU;
    161 		ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
    162 		ifp->if_ioctl = loioctl;
    163 		ifp->if_output = looutput;
    164 #ifdef ALTQ
    165 		ifp->if_start = lostart;
    166 #endif
    167 		ifp->if_type = IFT_LOOP;
    168 		ifp->if_hdrlen = 0;
    169 		ifp->if_addrlen = 0;
    170 		ifp->if_dlt = DLT_NULL;
    171 		IFQ_SET_READY(&ifp->if_snd);
    172 		if_attach(ifp);
    173 		if_alloc_sadl(ifp);
    174 #if NBPFILTER > 0
    175 		bpfattach(ifp, DLT_NULL, sizeof(u_int));
    176 #endif
    177 	}
    178 }
    179 
    180 int
    181 looutput(ifp, m, dst, rt)
    182 	struct ifnet *ifp;
    183 	struct mbuf *m;
    184 	struct sockaddr *dst;
    185 	struct rtentry *rt;
    186 {
    187 	int s, isr;
    188 	struct ifqueue *ifq = 0;
    189 
    190 	if ((m->m_flags & M_PKTHDR) == 0)
    191 		panic("looutput: no header mbuf");
    192 #if NBPFILTER > 0
    193 	if (ifp->if_bpf && (ifp->if_flags & IFF_LOOPBACK)) {
    194 		/*
    195 		 * We need to prepend the address family as
    196 		 * a four byte field.  Cons up a dummy header
    197 		 * to pacify bpf.  This is safe because bpf
    198 		 * will only read from the mbuf (i.e., it won't
    199 		 * try to free it or keep a pointer to it).
    200 		 */
    201 		struct mbuf m0;
    202 		u_int32_t af = dst->sa_family;
    203 
    204 		M_COPY_PKTHDR(&m0, m);
    205 		m0.m_next = m;
    206 		m0.m_len = 4;
    207 		m0.m_data = (char *)&af;
    208 		m0.m_pkthdr.len += m0.m_len;
    209 
    210 		bpf_mtap(ifp->if_bpf, &m0);
    211 	}
    212 #endif
    213 	m->m_pkthdr.rcvif = ifp;
    214 
    215 	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
    216 		m_freem(m);
    217 		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
    218 			rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
    219 	}
    220 
    221 #ifndef PULLDOWN_TEST
    222 	/*
    223 	 * KAME requires that the packet to be contiguous on the
    224 	 * mbuf.  We need to make that sure.
    225 	 * this kind of code should be avoided.
    226 	 * XXX other conditions to avoid running this part?
    227 	 */
    228 	if (m->m_len != m->m_pkthdr.len) {
    229 		struct mbuf *n = NULL;
    230 		int maxlen;
    231 
    232 		MGETHDR(n, M_DONTWAIT, MT_HEADER);
    233 		maxlen = MHLEN;
    234 		if (n)
    235 			M_COPY_PKTHDR(n, m);
    236 		if (n && m->m_pkthdr.len > maxlen) {
    237 			MCLGET(n, M_DONTWAIT);
    238 			maxlen = MCLBYTES;
    239 			if ((n->m_flags & M_EXT) == 0) {
    240 				m_free(n);
    241 				n = NULL;
    242 			}
    243 		}
    244 		if (!n) {
    245 			printf("looutput: mbuf allocation failed\n");
    246 			m_freem(m);
    247 			return ENOBUFS;
    248 		}
    249 
    250 		if (m->m_pkthdr.len <= maxlen) {
    251 			m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t));
    252 			n->m_len = m->m_pkthdr.len;
    253 			n->m_next = NULL;
    254 			m_freem(m);
    255 		} else {
    256 			m_copydata(m, 0, maxlen, mtod(n, caddr_t));
    257 			m_adj(m, maxlen);
    258 			n->m_len = maxlen;
    259 			n->m_next = m;
    260 			m->m_flags &= ~M_PKTHDR;
    261 		}
    262 		m = n;
    263 	}
    264 #if 0
    265 	if (m && m->m_next != NULL) {
    266 		printf("loop: not contiguous...\n");
    267 		m_freem(m);
    268 		return ENOBUFS;
    269 	}
    270 #endif
    271 #endif
    272 
    273 	ifp->if_opackets++;
    274 	ifp->if_obytes += m->m_pkthdr.len;
    275 
    276 #ifdef ALTQ
    277 	/*
    278 	 * ALTQ on the loopback interface is just for debugging.  It's
    279 	 * used only for loopback interfaces, not for a simplex interface.
    280 	 */
    281 	if ((ALTQ_IS_ENABLED(&ifp->if_snd) || TBR_IS_ENABLED(&ifp->if_snd)) &&
    282 	    ifp->if_start == lostart) {
    283 		struct altq_pktattr pktattr;
    284 		int error;
    285 
    286 		/*
    287 		 * If the queueing discipline needs packet classification,
    288 		 * do it before prepending the link headers.
    289 		 */
    290 		IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr);
    291 
    292 		M_PREPEND(m, sizeof(uint32_t), M_DONTWAIT);
    293 		if (m == NULL)
    294 			return (ENOBUFS);
    295 		*(mtod(m, uint32_t *)) = dst->sa_family;
    296 
    297 		s = splnet();
    298 		IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error);
    299 		(*ifp->if_start)(ifp);
    300 		splx(s);
    301 		return (error);
    302 	}
    303 #endif /* ALTQ */
    304 
    305 	switch (dst->sa_family) {
    306 
    307 #ifdef INET
    308 	case AF_INET:
    309 		ifq = &ipintrq;
    310 		isr = NETISR_IP;
    311 		break;
    312 #endif
    313 #ifdef INET6
    314 	case AF_INET6:
    315 		m->m_flags |= M_LOOP;
    316 		ifq = &ip6intrq;
    317 		isr = NETISR_IPV6;
    318 		break;
    319 #endif
    320 #ifdef NS
    321 	case AF_NS:
    322 		ifq = &nsintrq;
    323 		isr = NETISR_NS;
    324 		break;
    325 #endif
    326 #ifdef ISO
    327 	case AF_ISO:
    328 		ifq = &clnlintrq;
    329 		isr = NETISR_ISO;
    330 		break;
    331 #endif
    332 #ifdef IPX
    333 	case AF_IPX:
    334 		ifq = &ipxintrq;
    335 		isr = NETISR_IPX;
    336 		break;
    337 #endif
    338 #ifdef NETATALK
    339 	case AF_APPLETALK:
    340 	        ifq = &atintrq2;
    341 		isr = NETISR_ATALK;
    342 		break;
    343 #endif
    344 	default:
    345 		printf("%s: can't handle af%d\n", ifp->if_xname,
    346 		    dst->sa_family);
    347 		m_freem(m);
    348 		return (EAFNOSUPPORT);
    349 	}
    350 	s = splnet();
    351 	if (IF_QFULL(ifq)) {
    352 		IF_DROP(ifq);
    353 		m_freem(m);
    354 		splx(s);
    355 		return (ENOBUFS);
    356 	}
    357 	IF_ENQUEUE(ifq, m);
    358 	schednetisr(isr);
    359 	ifp->if_ipackets++;
    360 	ifp->if_ibytes += m->m_pkthdr.len;
    361 	splx(s);
    362 	return (0);
    363 }
    364 
    365 #ifdef ALTQ
    366 void
    367 lostart(struct ifnet *ifp)
    368 {
    369 	struct ifqueue *ifq;
    370 	struct mbuf *m;
    371 	uint32_t af;
    372 	int s, isr;
    373 
    374 	for (;;) {
    375 		IFQ_DEQUEUE(&ifp->if_snd, m);
    376 		if (m == NULL)
    377 			return;
    378 
    379 		af = *(mtod(m, uint32_t *));
    380 		m_adj(m, sizeof(uint32_t));
    381 
    382 		switch (af) {
    383 #ifdef INET
    384 		case AF_INET:
    385 			ifq = &ipintrq;
    386 			isr = NETISR_IP;
    387 			break;
    388 #endif
    389 #ifdef INET6
    390 		case AF_INET6:
    391 			m->m_flags |= M_LOOP;
    392 			ifq = &ip6intrq;
    393 			isr = NETISR_IPV6;
    394 			break;
    395 #endif
    396 #ifdef IPX
    397 		case AF_IPX:
    398 			ifq = &ipxintrq;
    399 			isr = NETISR_IPX;
    400 			break;
    401 #endif
    402 #ifdef NS
    403 		case AF_NS:
    404 			ifq = &nsintrq;
    405 			isr = NETISR_NS;
    406 			break;
    407 #endif
    408 #ifdef ISO
    409 		case AF_ISO:
    410 			ifq = &clnlintrq;
    411 			isr = NETISR_ISO;
    412 			break;
    413 #endif
    414 #ifdef NETATALK
    415 		case AF_APPLETALK:
    416 			ifq = &atintrq2;
    417 			isr = NETISR_ATALK;
    418 			break;
    419 #endif
    420 		default:
    421 			printf("%s: can't handle af%d\n", ifp->if_xname, af);
    422 			m_freem(m);
    423 			return;
    424 		}
    425 
    426 		s = splnet();
    427 		if (IF_QFULL(ifq)) {
    428 			IF_DROP(ifq);
    429 			splx(s);
    430 			m_freem(m);
    431 			return;
    432 		}
    433 		IF_ENQUEUE(ifq, m);
    434 		schednetisr(isr);
    435 		ifp->if_ipackets++;
    436 		ifp->if_ibytes += m->m_pkthdr.len;
    437 		splx(s);
    438 	}
    439 }
    440 #endif /* ALTQ */
    441 
    442 /* ARGSUSED */
    443 void
    444 lortrequest(cmd, rt, info)
    445 	int cmd;
    446 	struct rtentry *rt;
    447 	struct rt_addrinfo *info;
    448 {
    449 
    450 	if (rt)
    451 		rt->rt_rmx.rmx_mtu = LOMTU;
    452 }
    453 
    454 /*
    455  * Process an ioctl request.
    456  */
    457 /* ARGSUSED */
    458 int
    459 loioctl(ifp, cmd, data)
    460 	struct ifnet *ifp;
    461 	u_long cmd;
    462 	caddr_t data;
    463 {
    464 	struct ifaddr *ifa;
    465 	struct ifreq *ifr;
    466 	int error = 0;
    467 
    468 	switch (cmd) {
    469 
    470 	case SIOCSIFADDR:
    471 		ifp->if_flags |= IFF_UP;
    472 		ifa = (struct ifaddr *)data;
    473 		if (ifa != 0 /*&& ifa->ifa_addr->sa_family == AF_ISO*/)
    474 			ifa->ifa_rtrequest = lortrequest;
    475 		/*
    476 		 * Everything else is done at a higher level.
    477 		 */
    478 		break;
    479 
    480 	case SIOCADDMULTI:
    481 	case SIOCDELMULTI:
    482 		ifr = (struct ifreq *)data;
    483 		if (ifr == 0) {
    484 			error = EAFNOSUPPORT;		/* XXX */
    485 			break;
    486 		}
    487 		switch (ifr->ifr_addr.sa_family) {
    488 
    489 #ifdef INET
    490 		case AF_INET:
    491 			break;
    492 #endif
    493 #ifdef INET6
    494 		case AF_INET6:
    495 			break;
    496 #endif
    497 
    498 		default:
    499 			error = EAFNOSUPPORT;
    500 			break;
    501 		}
    502 		break;
    503 
    504 	default:
    505 		error = EINVAL;
    506 	}
    507 	return (error);
    508 }
    509