if_disc.c revision 10957
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 1.6 1995/09/09 18:10:21 davidg 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#include <machine/cpu.h> 51 52#include <net/if.h> 53#include <net/if_types.h> 54#include <net/netisr.h> 55#include <net/route.h> 56#include <net/bpf.h> 57 58#ifdef INET 59#include <netinet/in.h> 60#include <netinet/in_systm.h> 61#include <netinet/in_var.h> 62#include <netinet/ip.h> 63#endif 64 65#ifdef NS 66#include <netns/ns.h> 67#include <netns/ns_if.h> 68#endif 69 70#ifdef ISO 71#include <netiso/iso.h> 72#include <netiso/iso_var.h> 73#endif 74 75#include "bpfilter.h" 76 77#ifdef TINY_DSMTU 78#define DSMTU (1024+512) 79#else 80#define DSMTU 65532 81#endif 82 83static void discattach __P((void *udata)); 84PSEUDO_SET(discattach, if_disc); 85 86static struct ifnet dsif; 87static int dsoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 88 struct rtentry *); 89static int dsioctl(struct ifnet *, int, caddr_t); 90 91/* ARGSUSED */ 92static void 93discattach(udata) 94 void *udata; 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->if_bpf, 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 int s, isr; 120 register struct ifqueue *ifq = 0; 121 122 if ((m->m_flags & M_PKTHDR) == 0) 123 panic("dsoutput no HDR"); 124 ifp->if_lastchange = time; 125#if NBPFILTER > 0 126 /* BPF write needs to be handled specially */ 127 if (dst->sa_family == AF_UNSPEC) { 128 dst->sa_family = *(mtod(m, int *)); 129 m->m_len -= sizeof(int); 130 m->m_pkthdr.len -= sizeof(int); 131 m->m_data += sizeof(int); 132 } 133 134 if (dsif.if_bpf) { 135 /* 136 * We need to prepend the address family as 137 * a four byte field. Cons up a dummy header 138 * to pacify bpf. This is safe because bpf 139 * will only read from the mbuf (i.e., it won't 140 * try to free it or keep a pointer a to it). 141 */ 142 struct mbuf m0; 143 u_int af = dst->sa_family; 144 145 m0.m_next = m; 146 m0.m_len = 4; 147 m0.m_data = (char *)⁡ 148 149 bpf_mtap(dsif.if_bpf, &m0); 150 } 151#endif 152 m->m_pkthdr.rcvif = ifp; 153 154 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 155 m_freem(m); 156 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 157 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 158 } 159 ifp->if_opackets++; 160 ifp->if_obytes += m->m_pkthdr.len; 161 162 m_freem(m); 163 return 0; 164} 165 166/* ARGSUSED */ 167static void 168dsrtrequest(cmd, rt, sa) 169 int cmd; 170 struct rtentry *rt; 171 struct sockaddr *sa; 172{ 173 if (rt) 174 rt->rt_rmx.rmx_mtu = DSMTU; 175} 176 177/* 178 * Process an ioctl request. 179 */ 180/* ARGSUSED */ 181int 182dsioctl(ifp, cmd, data) 183 register struct ifnet *ifp; 184 int cmd; 185 caddr_t data; 186{ 187 register struct ifaddr *ifa; 188 register struct ifreq *ifr = (struct ifreq *)data; 189 register int error = 0; 190 191 switch (cmd) { 192 193 case SIOCSIFADDR: 194 ifp->if_flags |= IFF_UP; 195 ifa = (struct ifaddr *)data; 196 if (ifa != 0) 197 ifa->ifa_rtrequest = dsrtrequest; 198 /* 199 * Everything else is done at a higher level. 200 */ 201 break; 202 203 case SIOCADDMULTI: 204 case SIOCDELMULTI: 205 if (ifr == 0) { 206 error = EAFNOSUPPORT; /* XXX */ 207 break; 208 } 209 switch (ifr->ifr_addr.sa_family) { 210 211#ifdef INET 212 case AF_INET: 213 break; 214#endif 215 216 default: 217 error = EAFNOSUPPORT; 218 break; 219 } 220 break; 221 222 case SIOCSIFMTU: 223 ifp->if_mtu = ifr->ifr_mtu; 224 break; 225 226 default: 227 error = EINVAL; 228 } 229 return (error); 230} 231