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if_loop.c revision 1.31 
      1 /*	$NetBSD: if_loop.c,v 1.31 2000/12/12 18:00:27 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 void
    143 loopattach(n)
    144 	int n;
    145 {
    146 	int i;
    147 	struct ifnet *ifp;
    148 
    149 	for (i = 0; i < NLOOP; i++) {
    150 		ifp = &loif[i];
    151 		sprintf(ifp->if_xname, "lo%d", i);
    152 		ifp->if_softc = NULL;
    153 		ifp->if_mtu = LOMTU;
    154 		ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST;
    155 		ifp->if_ioctl = loioctl;
    156 		ifp->if_output = looutput;
    157 		ifp->if_type = IFT_LOOP;
    158 		ifp->if_hdrlen = 0;
    159 		ifp->if_addrlen = 0;
    160 		if_attach(ifp);
    161 #if NBPFILTER > 0
    162 		bpfattach(ifp, DLT_NULL, sizeof(u_int));
    163 #endif
    164 	}
    165 }
    166 
    167 int
    168 looutput(ifp, m, dst, rt)
    169 	struct ifnet *ifp;
    170 	struct mbuf *m;
    171 	struct sockaddr *dst;
    172 	struct rtentry *rt;
    173 {
    174 	int s, isr;
    175 	struct ifqueue *ifq = 0;
    176 
    177 	if ((m->m_flags & M_PKTHDR) == 0)
    178 		panic("looutput: no header mbuf");
    179 	ifp->if_lastchange = time;
    180 #if NBPFILTER > 0
    181 	if (ifp->if_bpf && (ifp->if_flags & IFF_LOOPBACK)) {
    182 		/*
    183 		 * We need to prepend the address family as
    184 		 * a four byte field.  Cons up a dummy header
    185 		 * to pacify bpf.  This is safe because bpf
    186 		 * will only read from the mbuf (i.e., it won't
    187 		 * try to free it or keep a pointer to it).
    188 		 */
    189 		struct mbuf m0;
    190 		u_int af = dst->sa_family;
    191 
    192 		m0.m_next = m;
    193 		m0.m_len = 4;
    194 		m0.m_data = (char *)&af;
    195 
    196 		bpf_mtap(ifp->if_bpf, &m0);
    197 	}
    198 #endif
    199 	m->m_pkthdr.rcvif = ifp;
    200 
    201 	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
    202 		m_freem(m);
    203 		return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
    204 			rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
    205 	}
    206 
    207 #ifndef PULLDOWN_TEST
    208 	/*
    209 	 * KAME requires that the packet to be contiguous on the
    210 	 * mbuf.  We need to make that sure.
    211 	 * this kind of code should be avoided.
    212 	 * XXX other conditions to avoid running this part?
    213 	 */
    214 	if (m->m_len != m->m_pkthdr.len) {
    215 		struct mbuf *n = NULL;
    216 		int maxlen;
    217 
    218 		MGETHDR(n, M_DONTWAIT, MT_HEADER);
    219 		maxlen = MHLEN;
    220 		if (n)
    221 			M_COPY_PKTHDR(n, m);
    222 		if (n && m->m_pkthdr.len > maxlen) {
    223 			MCLGET(n, M_DONTWAIT);
    224 			maxlen = MCLBYTES;
    225 			if ((n->m_flags & M_EXT) == 0) {
    226 				m_free(n);
    227 				n = NULL;
    228 			}
    229 		}
    230 		if (!n) {
    231 			printf("looutput: mbuf allocation failed\n");
    232 			m_freem(m);
    233 			return ENOBUFS;
    234 		}
    235 
    236 		if (m->m_pkthdr.len <= maxlen) {
    237 			m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t));
    238 			n->m_len = m->m_pkthdr.len;
    239 			n->m_next = NULL;
    240 			m_freem(m);
    241 		} else {
    242 			m_copydata(m, 0, maxlen, mtod(n, caddr_t));
    243 			m_adj(m, maxlen);
    244 			n->m_len = maxlen;
    245 			n->m_next = m;
    246 			m->m_flags &= ~M_PKTHDR;
    247 		}
    248 		m = n;
    249 	}
    250 #if 0
    251 	if (m && m->m_next != NULL) {
    252 		printf("loop: not contiguous...\n");
    253 		m_freem(m);
    254 		return ENOBUFS;
    255 	}
    256 #endif
    257 #endif
    258 
    259 	ifp->if_opackets++;
    260 	ifp->if_obytes += m->m_pkthdr.len;
    261 	switch (dst->sa_family) {
    262 
    263 #ifdef INET
    264 	case AF_INET:
    265 		ifq = &ipintrq;
    266 		isr = NETISR_IP;
    267 		break;
    268 #endif
    269 #ifdef INET6
    270 	case AF_INET6:
    271 		m->m_flags |= M_LOOP;
    272 		ifq = &ip6intrq;
    273 		isr = NETISR_IPV6;
    274 		break;
    275 #endif
    276 #ifdef NS
    277 	case AF_NS:
    278 		ifq = &nsintrq;
    279 		isr = NETISR_NS;
    280 		break;
    281 #endif
    282 #ifdef ISO
    283 	case AF_ISO:
    284 		ifq = &clnlintrq;
    285 		isr = NETISR_ISO;
    286 		break;
    287 #endif
    288 #ifdef IPX
    289 	case AF_IPX:
    290 		ifq = &ipxintrq;
    291 		isr = NETISR_IPX;
    292 		break;
    293 #endif
    294 #ifdef NETATALK
    295 	case AF_APPLETALK:
    296 	        ifq = &atintrq2;
    297 		isr = NETISR_ATALK;
    298 		break;
    299 #endif
    300 	default:
    301 		printf("%s: can't handle af%d\n", ifp->if_xname,
    302 		    dst->sa_family);
    303 		m_freem(m);
    304 		return (EAFNOSUPPORT);
    305 	}
    306 	s = splimp();
    307 	if (IF_QFULL(ifq)) {
    308 		IF_DROP(ifq);
    309 		m_freem(m);
    310 		splx(s);
    311 		return (ENOBUFS);
    312 	}
    313 	IF_ENQUEUE(ifq, m);
    314 	schednetisr(isr);
    315 	ifp->if_ipackets++;
    316 	ifp->if_ibytes += m->m_pkthdr.len;
    317 	splx(s);
    318 	return (0);
    319 }
    320 
    321 /* ARGSUSED */
    322 void
    323 lortrequest(cmd, rt, sa)
    324 	int cmd;
    325 	struct rtentry *rt;
    326 	struct sockaddr *sa;
    327 {
    328 
    329 	if (rt)
    330 		rt->rt_rmx.rmx_mtu = LOMTU;
    331 }
    332 
    333 /*
    334  * Process an ioctl request.
    335  */
    336 /* ARGSUSED */
    337 int
    338 loioctl(ifp, cmd, data)
    339 	struct ifnet *ifp;
    340 	u_long cmd;
    341 	caddr_t data;
    342 {
    343 	struct ifaddr *ifa;
    344 	struct ifreq *ifr;
    345 	int error = 0;
    346 
    347 	switch (cmd) {
    348 
    349 	case SIOCSIFADDR:
    350 		ifp->if_flags |= IFF_UP;
    351 		ifa = (struct ifaddr *)data;
    352 		if (ifa != 0 /*&& ifa->ifa_addr->sa_family == AF_ISO*/)
    353 			ifa->ifa_rtrequest = lortrequest;
    354 		/*
    355 		 * Everything else is done at a higher level.
    356 		 */
    357 		break;
    358 
    359 	case SIOCADDMULTI:
    360 	case SIOCDELMULTI:
    361 		ifr = (struct ifreq *)data;
    362 		if (ifr == 0) {
    363 			error = EAFNOSUPPORT;		/* XXX */
    364 			break;
    365 		}
    366 		switch (ifr->ifr_addr.sa_family) {
    367 
    368 #ifdef INET
    369 		case AF_INET:
    370 			break;
    371 #endif
    372 #ifdef INET6
    373 		case AF_INET6:
    374 			break;
    375 #endif
    376 
    377 		default:
    378 			error = EAFNOSUPPORT;
    379 			break;
    380 		}
    381 		break;
    382 
    383 	default:
    384 		error = EINVAL;
    385 	}
    386 	return (error);
    387 }
    388