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if_loop.c revision 1.38 
      1 /*	$NetBSD: if_loop.c,v 1.38 2001/04/13 23:30:14 thorpej 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 "opt_inet.h"
     72 #include "opt_atalk.h"
     73 #include "opt_iso.h"
     74 #include "opt_ns.h"
     75 
     76 #include "bpfilter.h"
     77 #include "loop.h"
     78 
     79 #include <sys/param.h>
     80 #include <sys/systm.h>
     81 #include <sys/kernel.h>
     82 #include <sys/mbuf.h>
     83 #include <sys/socket.h>
     84 #include <sys/errno.h>
     85 #include <sys/ioctl.h>
     86 #include <sys/time.h>
     87 
     88 #include <machine/cpu.h>
     89 
     90 #include <net/if.h>
     91 #include <net/if_types.h>
     92 #include <net/netisr.h>
     93 #include <net/route.h>
     94 
     95 #ifdef	INET
     96 #include <netinet/in.h>
     97 #include <netinet/in_systm.h>
     98 #include <netinet/in_var.h>
     99 #include <netinet/ip.h>
    100 #endif
    101 
    102 #ifdef INET6
    103 #ifndef INET
    104 #include <netinet/in.h>
    105 #endif
    106 #include <netinet6/in6_var.h>
    107 #include <netinet/ip6.h>
    108 #endif
    109 
    110 #ifdef NS
    111 #include <netns/ns.h>
    112 #include <netns/ns_if.h>
    113 #endif
    114 
    115 #ifdef IPX
    116 #include <netipx/ipx.h>
    117 #include <netipx/ipx_if.h>
    118 #endif
    119 
    120 #ifdef ISO
    121 #include <netiso/iso.h>
    122 #include <netiso/iso_var.h>
    123 #endif
    124 
    125 #ifdef NETATALK
    126 #include <netatalk/at.h>
    127 #include <netatalk/at_var.h>
    128 #endif
    129 
    130 #if NBPFILTER > 0
    131 #include <net/bpf.h>
    132 #endif
    133 
    134 #if defined(LARGE_LOMTU)
    135 #define LOMTU	(131072 +  MHLEN + MLEN)
    136 #else
    137 #define	LOMTU	(32768 +  MHLEN + MLEN)
    138 #endif
    139 
    140 struct	ifnet loif[NLOOP];
    141 
    142 #ifdef ALTQ
    143 void	lostart(struct ifnet *);
    144 #endif
    145 
    146 void
    147 loopattach(n)
    148 	int n;
    149 {
    150 	int i;
    151 	struct ifnet *ifp;
    152 
    153 	for (i = 0; i < NLOOP; i++) {
    154 		ifp = &loif[i];
    155 		sprintf(ifp->if_xname, "lo%d", i);
    156 		ifp->if_softc = NULL;
    157 		ifp->if_mtu = LOMTU;
    158 		ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
    159 		ifp->if_ioctl = loioctl;
    160 		ifp->if_output = looutput;
    161 #ifdef ALTQ
    162 		ifp->if_start = lostart;
    163 #endif
    164 		ifp->if_type = IFT_LOOP;
    165 		ifp->if_hdrlen = 0;
    166 		ifp->if_addrlen = 0;
    167 		ifp->if_dlt = DLT_NULL;
    168 		IFQ_SET_READY(&ifp->if_snd);
    169 		if_attach(ifp);
    170 		if_alloc_sadl(ifp);
    171 #if NBPFILTER > 0
    172 		bpfattach(ifp, DLT_NULL, sizeof(u_int));
    173 #endif
    174 	}
    175 }
    176 
    177 int
    178 looutput(ifp, m, dst, rt)
    179 	struct ifnet *ifp;
    180 	struct mbuf *m;
    181 	struct sockaddr *dst;
    182 	struct rtentry *rt;
    183 {
    184 	int s, isr;
    185 	struct ifqueue *ifq = 0;
    186 
    187 	if ((m->m_flags & M_PKTHDR) == 0)
    188 		panic("looutput: no header mbuf");
    189 	ifp->if_lastchange = time;
    190 #if NBPFILTER > 0
    191 	if (ifp->if_bpf && (ifp->if_flags & IFF_LOOPBACK)) {
    192 		/*
    193 		 * We need to prepend the address family as
    194 		 * a four byte field.  Cons up a dummy header
    195 		 * to pacify bpf.  This is safe because bpf
    196 		 * will only read from the mbuf (i.e., it won't
    197 		 * try to free it or keep a pointer to it).
    198 		 */
    199 		struct mbuf m0;
    200 		u_int32_t af = dst->sa_family;
    201 
    202 		m0.m_next = m;
    203 		m0.m_len = 4;
    204 		m0.m_data = (char *)&af;
    205 
    206 		bpf_mtap(ifp->if_bpf, &m0);
    207 	}
    208 #endif
    209 	m->m_pkthdr.rcvif = ifp;
    210 
    211 	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
    212 		m_freem(m);
    213 		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
    214 			rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
    215 	}
    216 
    217 #ifndef PULLDOWN_TEST
    218 	/*
    219 	 * KAME requires that the packet to be contiguous on the
    220 	 * mbuf.  We need to make that sure.
    221 	 * this kind of code should be avoided.
    222 	 * XXX other conditions to avoid running this part?
    223 	 */
    224 	if (m->m_len != m->m_pkthdr.len) {
    225 		struct mbuf *n = NULL;
    226 		int maxlen;
    227 
    228 		MGETHDR(n, M_DONTWAIT, MT_HEADER);
    229 		maxlen = MHLEN;
    230 		if (n)
    231 			M_COPY_PKTHDR(n, m);
    232 		if (n && m->m_pkthdr.len > maxlen) {
    233 			MCLGET(n, M_DONTWAIT);
    234 			maxlen = MCLBYTES;
    235 			if ((n->m_flags & M_EXT) == 0) {
    236 				m_free(n);
    237 				n = NULL;
    238 			}
    239 		}
    240 		if (!n) {
    241 			printf("looutput: mbuf allocation failed\n");
    242 			m_freem(m);
    243 			return ENOBUFS;
    244 		}
    245 
    246 		if (m->m_pkthdr.len <= maxlen) {
    247 			m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t));
    248 			n->m_len = m->m_pkthdr.len;
    249 			n->m_next = NULL;
    250 			m_freem(m);
    251 		} else {
    252 			m_copydata(m, 0, maxlen, mtod(n, caddr_t));
    253 			m_adj(m, maxlen);
    254 			n->m_len = maxlen;
    255 			n->m_next = m;
    256 			m->m_flags &= ~M_PKTHDR;
    257 		}
    258 		m = n;
    259 	}
    260 #if 0
    261 	if (m && m->m_next != NULL) {
    262 		printf("loop: not contiguous...\n");
    263 		m_freem(m);
    264 		return ENOBUFS;
    265 	}
    266 #endif
    267 #endif
    268 
    269 	ifp->if_opackets++;
    270 	ifp->if_obytes += m->m_pkthdr.len;
    271 
    272 #ifdef ALTQ
    273 	/*
    274 	 * ALTQ on the loopback interface is just for debugging.  It's
    275 	 * used only for loopback interfaces, not for a simplex interface.
    276 	 */
    277 	if ((ALTQ_IS_ENABLED(&ifp->if_snd) || TBR_IS_ENABLED(&ifp->if_snd)) &&
    278 	    ifp->if_start == lostart) {
    279 		struct altq_pktattr pktattr;
    280 		int error;
    281 
    282 		/*
    283 		 * If the queueing discipline needs packet classification,
    284 		 * do it before prepending the link headers.
    285 		 */
    286 		IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family, &pktattr);
    287 
    288 		M_PREPEND(m, sizeof(uint32_t), M_DONTWAIT);
    289 		if (m == NULL)
    290 			return (ENOBUFS);
    291 		*(mtod(m, uint32_t *)) = dst->sa_family;
    292 
    293 		s = splnet();
    294 		IFQ_ENQUEUE(&ifp->if_snd, m, &pktattr, error);
    295 		(*ifp->if_start)(ifp);
    296 		splx(s);
    297 		return (error);
    298 	}
    299 #endif /* ALTQ */
    300 
    301 	switch (dst->sa_family) {
    302 
    303 #ifdef INET
    304 	case AF_INET:
    305 		ifq = &ipintrq;
    306 		isr = NETISR_IP;
    307 		break;
    308 #endif
    309 #ifdef INET6
    310 	case AF_INET6:
    311 		m->m_flags |= M_LOOP;
    312 		ifq = &ip6intrq;
    313 		isr = NETISR_IPV6;
    314 		break;
    315 #endif
    316 #ifdef NS
    317 	case AF_NS:
    318 		ifq = &nsintrq;
    319 		isr = NETISR_NS;
    320 		break;
    321 #endif
    322 #ifdef ISO
    323 	case AF_ISO:
    324 		ifq = &clnlintrq;
    325 		isr = NETISR_ISO;
    326 		break;
    327 #endif
    328 #ifdef IPX
    329 	case AF_IPX:
    330 		ifq = &ipxintrq;
    331 		isr = NETISR_IPX;
    332 		break;
    333 #endif
    334 #ifdef NETATALK
    335 	case AF_APPLETALK:
    336 	        ifq = &atintrq2;
    337 		isr = NETISR_ATALK;
    338 		break;
    339 #endif
    340 	default:
    341 		printf("%s: can't handle af%d\n", ifp->if_xname,
    342 		    dst->sa_family);
    343 		m_freem(m);
    344 		return (EAFNOSUPPORT);
    345 	}
    346 	s = splnet();
    347 	if (IF_QFULL(ifq)) {
    348 		IF_DROP(ifq);
    349 		m_freem(m);
    350 		splx(s);
    351 		return (ENOBUFS);
    352 	}
    353 	IF_ENQUEUE(ifq, m);
    354 	schednetisr(isr);
    355 	ifp->if_ipackets++;
    356 	ifp->if_ibytes += m->m_pkthdr.len;
    357 	splx(s);
    358 	return (0);
    359 }
    360 
    361 #ifdef ALTQ
    362 void
    363 lostart(struct ifnet *ifp)
    364 {
    365 	struct ifqueue *ifq;
    366 	struct mbuf *m;
    367 	uint32_t af;
    368 	int s, isr;
    369 
    370 	for (;;) {
    371 		IFQ_DEQUEUE(&ifp->if_snd, m);
    372 		if (m == NULL)
    373 			return;
    374 
    375 		af = *(mtod(m, uint32_t *));
    376 		m_adj(m, sizeof(uint32_t));
    377 
    378 		switch (af) {
    379 #ifdef INET
    380 		case AF_INET:
    381 			ifq = &ipintrq;
    382 			isr = NETISR_IP;
    383 			break;
    384 #endif
    385 #ifdef INET6
    386 		case AF_INET6:
    387 			m->m_flags |= M_LOOP;
    388 			ifq = &ip6intrq;
    389 			isr = NETISR_IPV6;
    390 			break;
    391 #endif
    392 #ifdef IPX
    393 		case AF_IPX:
    394 			ifq = &ipxintrq;
    395 			isr = NETISR_IPX;
    396 			break;
    397 #endif
    398 #ifdef NS
    399 		case AF_NS:
    400 			ifq = &nsintrq;
    401 			isr = NETISR_NS;
    402 			break;
    403 #endif
    404 #ifdef ISO
    405 		case AF_ISO:
    406 			ifq = &clnlintrq;
    407 			isr = NETISR_ISO;
    408 			break;
    409 #endif
    410 #ifdef NETATALK
    411 		case AF_APPLETALK:
    412 			ifq = &atintrq2;
    413 			isr = NETISR_ATALK;
    414 			break;
    415 #endif
    416 		default:
    417 			printf("%s: can't handle af%d\n", ifp->if_xname, af);
    418 			m_freem(m);
    419 			return;
    420 		}
    421 
    422 		s = splnet();
    423 		if (IF_QFULL(ifq)) {
    424 			IF_DROP(ifq);
    425 			splx(s);
    426 			m_freem(m);
    427 			return;
    428 		}
    429 		IF_ENQUEUE(ifq, m);
    430 		schednetisr(isr);
    431 		ifp->if_ipackets++;
    432 		ifp->if_ibytes += m->m_pkthdr.len;
    433 		splx(s);
    434 	}
    435 }
    436 #endif /* ALTQ */
    437 
    438 /* ARGSUSED */
    439 void
    440 lortrequest(cmd, rt, info)
    441 	int cmd;
    442 	struct rtentry *rt;
    443 	struct rt_addrinfo *info;
    444 {
    445 
    446 	if (rt)
    447 		rt->rt_rmx.rmx_mtu = LOMTU;
    448 }
    449 
    450 /*
    451  * Process an ioctl request.
    452  */
    453 /* ARGSUSED */
    454 int
    455 loioctl(ifp, cmd, data)
    456 	struct ifnet *ifp;
    457 	u_long cmd;
    458 	caddr_t data;
    459 {
    460 	struct ifaddr *ifa;
    461 	struct ifreq *ifr;
    462 	int error = 0;
    463 
    464 	switch (cmd) {
    465 
    466 	case SIOCSIFADDR:
    467 		ifp->if_flags |= IFF_UP;
    468 		ifa = (struct ifaddr *)data;
    469 		if (ifa != 0 /*&& ifa->ifa_addr->sa_family == AF_ISO*/)
    470 			ifa->ifa_rtrequest = lortrequest;
    471 		/*
    472 		 * Everything else is done at a higher level.
    473 		 */
    474 		break;
    475 
    476 	case SIOCADDMULTI:
    477 	case SIOCDELMULTI:
    478 		ifr = (struct ifreq *)data;
    479 		if (ifr == 0) {
    480 			error = EAFNOSUPPORT;		/* XXX */
    481 			break;
    482 		}
    483 		switch (ifr->ifr_addr.sa_family) {
    484 
    485 #ifdef INET
    486 		case AF_INET:
    487 			break;
    488 #endif
    489 #ifdef INET6
    490 		case AF_INET6:
    491 			break;
    492 #endif
    493 
    494 		default:
    495 			error = EAFNOSUPPORT;
    496 			break;
    497 		}
    498 		break;
    499 
    500 	default:
    501 		error = EINVAL;
    502 	}
    503 	return (error);
    504 }
    505