1 /* $NetBSD: if_loop.c,v 1.20 1997/08/14 01:12:35 jonathan Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)if_loop.c 8.1 (Berkeley) 6/10/93 36 */ 37 38 /* 39 * Loopback interface driver for protocol testing and timing. 40 */ 41 42 #include "bpfilter.h" 43 #include "loop.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/mbuf.h> 49 #include <sys/socket.h> 50 #include <sys/errno.h> 51 #include <sys/ioctl.h> 52 #include <sys/time.h> 53 54 #include <machine/cpu.h> 55 56 #include <net/if.h> 57 #include <net/if_types.h> 58 #include <net/netisr.h> 59 #include <net/route.h> 60 61 #ifdef INET 62 #include <netinet/in.h> 63 #include <netinet/in_systm.h> 64 #include <netinet/in_var.h> 65 #include <netinet/ip.h> 66 #endif 67 68 #ifdef NS 69 #include <netns/ns.h> 70 #include <netns/ns_if.h> 71 #endif 72 73 #ifdef ISO 74 #include <netiso/iso.h> 75 #include <netiso/iso_var.h> 76 #endif 77 78 #ifdef NETATALK 79 #include <netatalk/at.h> 80 #include <netatalk/at_var.h> 81 #endif 82 83 #if NBPFILTER > 0 84 #include <net/bpf.h> 85 #endif 86 87 #define LOMTU (32768 + MHLEN + MLEN) 88 89 struct ifnet loif[NLOOP]; 90 91 void 92 loopattach(n) 93 int n; 94 { 95 register int i; 96 register struct ifnet *ifp; 97 98 for (i = 0; i < NLOOP; i++) { 99 ifp = &loif[i]; 100 sprintf(ifp->if_xname, "lo%d", i); 101 ifp->if_softc = NULL; 102 ifp->if_mtu = LOMTU; 103 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 104 ifp->if_ioctl = loioctl; 105 ifp->if_output = looutput; 106 ifp->if_type = IFT_LOOP; 107 ifp->if_hdrlen = 0; 108 ifp->if_addrlen = 0; 109 if_attach(ifp); 110 #if NBPFILTER > 0 111 bpfattach(&ifp->if_bpf, ifp, DLT_NULL, sizeof(u_int)); 112 #endif 113 } 114 } 115 116 int 117 looutput(ifp, m, dst, rt) 118 struct ifnet *ifp; 119 register struct mbuf *m; 120 struct sockaddr *dst; 121 register struct rtentry *rt; 122 { 123 int s, isr; 124 register struct ifqueue *ifq = 0; 125 126 if ((m->m_flags & M_PKTHDR) == 0) 127 panic("looutput: no header mbuf"); 128 ifp->if_lastchange = time; 129 #if NBPFILTER > 0 130 if (ifp->if_bpf && (ifp->if_flags & IFF_LOOPBACK)) { 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 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(ifp->if_bpf, &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 switch (dst->sa_family) { 158 159 #ifdef INET 160 case AF_INET: 161 ifq = &ipintrq; 162 isr = NETISR_IP; 163 break; 164 #endif 165 #ifdef NS 166 case AF_NS: 167 ifq = &nsintrq; 168 isr = NETISR_NS; 169 break; 170 #endif 171 #ifdef ISO 172 case AF_ISO: 173 ifq = &clnlintrq; 174 isr = NETISR_ISO; 175 break; 176 #endif 177 #ifdef NETATALK 178 case AF_APPLETALK: 179 ifq = &atintrq2; 180 isr = NETISR_ATALK; 181 break; 182 #endif 183 default: 184 printf("%s: can't handle af%d\n", ifp->if_xname, 185 dst->sa_family); 186 m_freem(m); 187 return (EAFNOSUPPORT); 188 } 189 s = splimp(); 190 if (IF_QFULL(ifq)) { 191 IF_DROP(ifq); 192 m_freem(m); 193 splx(s); 194 return (ENOBUFS); 195 } 196 IF_ENQUEUE(ifq, m); 197 schednetisr(isr); 198 ifp->if_ipackets++; 199 ifp->if_ibytes += m->m_pkthdr.len; 200 splx(s); 201 return (0); 202 } 203 204 /* ARGSUSED */ 205 void 206 lortrequest(cmd, rt, sa) 207 int cmd; 208 struct rtentry *rt; 209 struct sockaddr *sa; 210 { 211 212 if (rt) 213 rt->rt_rmx.rmx_mtu = LOMTU; 214 } 215 216 /* 217 * Process an ioctl request. 218 */ 219 /* ARGSUSED */ 220 int 221 loioctl(ifp, cmd, data) 222 register struct ifnet *ifp; 223 u_long cmd; 224 caddr_t data; 225 { 226 register struct ifaddr *ifa; 227 register struct ifreq *ifr; 228 register int error = 0; 229 230 switch (cmd) { 231 232 case SIOCSIFADDR: 233 ifp->if_flags |= IFF_UP; 234 ifa = (struct ifaddr *)data; 235 if (ifa != 0 && ifa->ifa_addr->sa_family == AF_ISO) 236 ifa->ifa_rtrequest = lortrequest; 237 /* 238 * Everything else is done at a higher level. 239 */ 240 break; 241 242 case SIOCADDMULTI: 243 case SIOCDELMULTI: 244 ifr = (struct ifreq *)data; 245 if (ifr == 0) { 246 error = EAFNOSUPPORT; /* XXX */ 247 break; 248 } 249 switch (ifr->ifr_addr.sa_family) { 250 251 #ifdef INET 252 case AF_INET: 253 break; 254 #endif 255 256 default: 257 error = EAFNOSUPPORT; 258 break; 259 } 260 break; 261 262 default: 263 error = EINVAL; 264 } 265 return (error); 266 } 267