if_disc.c revision 16287
1/* 2 * Copyright (c) 1982, 1986, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * From: @(#)if_loop.c 8.1 (Berkeley) 6/10/93 34 * $Id: if_disc.c,v 1.12 1996/04/07 17:39:03 bde Exp $ 35 */ 36 37/* 38 * Discard interface driver for protocol testing and timing. 39 * (Based on the loopback.) 40 */ 41 42#include <sys/param.h> 43#include <sys/systm.h> 44#include <sys/kernel.h> 45#include <sys/mbuf.h> 46#include <sys/socket.h> 47#include <sys/errno.h> 48#include <sys/ioctl.h> 49#include <sys/time.h> 50 51#include <net/if.h> 52#include <net/if_types.h> 53#include <net/netisr.h> 54#include <net/route.h> 55#include <net/bpf.h> 56 57#ifdef INET 58#include <netinet/in.h> 59#include <netinet/in_systm.h> 60#include <netinet/in_var.h> 61#include <netinet/ip.h> 62#endif 63 64#ifdef NS 65#include <netns/ns.h> 66#include <netns/ns_if.h> 67#endif 68 69#ifdef ISO 70#include <netiso/iso.h> 71#include <netiso/iso_var.h> 72#endif 73 74#include "bpfilter.h" 75 76#ifdef TINY_DSMTU 77#define DSMTU (1024+512) 78#else 79#define DSMTU 65532 80#endif 81 82static void discattach __P((void *dummy)); 83PSEUDO_SET(discattach, if_disc); 84 85static struct ifnet dsif; 86static int dsoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 87 struct rtentry *); 88static void dsrtrequest(int cmd, struct rtentry *rt, struct sockaddr *sa); 89static int dsioctl(struct ifnet *, int, caddr_t); 90 91/* ARGSUSED */ 92static void 93discattach(dummy) 94 void *dummy; 95{ 96 register struct ifnet *ifp = &dsif; 97 98 ifp->if_name = "ds"; 99 ifp->if_mtu = DSMTU; 100 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 101 ifp->if_ioctl = dsioctl; 102 ifp->if_output = dsoutput; 103 ifp->if_type = IFT_LOOP; 104 ifp->if_hdrlen = 0; 105 ifp->if_addrlen = 0; 106 if_attach(ifp); 107#if NBPFILTER > 0 108 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 109#endif 110} 111 112static int 113dsoutput(ifp, m, dst, rt) 114 struct ifnet *ifp; 115 register struct mbuf *m; 116 struct sockaddr *dst; 117 register struct rtentry *rt; 118{ 119 if ((m->m_flags & M_PKTHDR) == 0) 120 panic("dsoutput no HDR"); 121#if NBPFILTER > 0 122 /* BPF write needs to be handled specially */ 123 if (dst->sa_family == AF_UNSPEC) { 124 dst->sa_family = *(mtod(m, int *)); 125 m->m_len -= sizeof(int); 126 m->m_pkthdr.len -= sizeof(int); 127 m->m_data += sizeof(int); 128 } 129 130 if (dsif.if_bpf) { 131 /* 132 * We need to prepend the address family as 133 * a four byte field. Cons up a dummy header 134 * to pacify bpf. This is safe because bpf 135 * will only read from the mbuf (i.e., it won't 136 * try to free it or keep a pointer a to it). 137 */ 138 struct mbuf m0; 139 u_int af = dst->sa_family; 140 141 m0.m_next = m; 142 m0.m_len = 4; 143 m0.m_data = (char *)⁡ 144 145 bpf_mtap(&dsif, &m0); 146 } 147#endif 148 m->m_pkthdr.rcvif = ifp; 149 150 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 151 m_freem(m); 152 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 153 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 154 } 155 ifp->if_opackets++; 156 ifp->if_obytes += m->m_pkthdr.len; 157 158 m_freem(m); 159 return 0; 160} 161 162/* ARGSUSED */ 163static void 164dsrtrequest(cmd, rt, sa) 165 int cmd; 166 struct rtentry *rt; 167 struct sockaddr *sa; 168{ 169 if (rt) 170 rt->rt_rmx.rmx_mtu = DSMTU; 171} 172 173/* 174 * Process an ioctl request. 175 */ 176/* ARGSUSED */ 177static int 178dsioctl(ifp, cmd, data) 179 register struct ifnet *ifp; 180 int cmd; 181 caddr_t data; 182{ 183 register struct ifaddr *ifa; 184 register struct ifreq *ifr = (struct ifreq *)data; 185 register int error = 0; 186 187 switch (cmd) { 188 189 case SIOCSIFADDR: 190 ifp->if_flags |= IFF_UP; 191 ifa = (struct ifaddr *)data; 192 if (ifa != 0) 193 ifa->ifa_rtrequest = dsrtrequest; 194 /* 195 * Everything else is done at a higher level. 196 */ 197 break; 198 199 case SIOCADDMULTI: 200 case SIOCDELMULTI: 201 if (ifr == 0) { 202 error = EAFNOSUPPORT; /* XXX */ 203 break; 204 } 205 switch (ifr->ifr_addr.sa_family) { 206 207#ifdef INET 208 case AF_INET: 209 break; 210#endif 211 212 default: 213 error = EAFNOSUPPORT; 214 break; 215 } 216 break; 217 218 case SIOCSIFMTU: 219 ifp->if_mtu = ifr->ifr_mtu; 220 break; 221 222 default: 223 error = EINVAL; 224 } 225 return (error); 226} 227