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 * @(#)if_loop.c 8.1 (Berkeley) 6/10/93 34 * $Id: if_loop.c,v 1.37 1998/07/12 16:46:52 dfr Exp $ 35 */ 36 37 /* 38 * Loopback interface driver for protocol testing and timing. 39 */ 40 #include "loop.h" 41 #if NLOOP > 0 42 43 #include "opt_atalk.h" 44 #include "opt_inet.h" 45 #include "opt_ipx.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/mbuf.h> 51 #include <sys/socket.h> 52 #include <sys/sockio.h> 53 54 #include <net/if.h> 55 #include <net/if_types.h> 56 #include <net/netisr.h> 57 #include <net/route.h> 58 #include <net/bpf.h> 59 60 #ifdef INET 61 #include <netinet/in.h> 62 #include <netinet/in_var.h> 63 #endif 64 65 #ifdef IPX 66 #include <netipx/ipx.h> 67 #include <netipx/ipx_if.h> 68 #endif 69 70 #ifdef NS 71 #include <netns/ns.h> 72 #include <netns/ns_if.h> 73 #endif 74 75 #ifdef ISO 76 #include <netiso/iso.h> 77 #include <netiso/iso_var.h> 78 #endif 79 80 #ifdef NETATALK 81 #include <netatalk/at.h> 82 #include <netatalk/at_var.h> 83 #endif NETATALK 84 85 #include "bpfilter.h" 86 #if NBPFILTER > 0 87 #include <net/bpfdesc.h> 88 #endif 89 90 static int loioctl __P((struct ifnet *, u_long, caddr_t)); 91 static void lortrequest __P((int, struct rtentry *, struct sockaddr *)); 92 93 static void loopattach __P((void *)); 94 PSEUDO_SET(loopattach, if_loop); 95 96 static int looutput __P((struct ifnet *ifp, 97 struct mbuf *m, struct sockaddr *dst, struct rtentry *rt)); 98 99 #ifdef TINY_LOMTU 100 #define LOMTU (1024+512) 101 #else 102 #define LOMTU 16384 103 #endif 104 105 struct ifnet loif[NLOOP]; 106 107 /* ARGSUSED */ 108 static void 109 loopattach(dummy) 110 void *dummy; 111 { 112 register struct ifnet *ifp; 113 register int i = 0; 114 115 for (ifp = loif; i < NLOOP; ifp++) { 116 ifp->if_name = "lo"; 117 ifp->if_unit = i++; 118 ifp->if_mtu = LOMTU; 119 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 120 ifp->if_ioctl = loioctl; 121 ifp->if_output = looutput; 122 ifp->if_type = IFT_LOOP; 123 ifp->if_snd.ifq_maxlen = ifqmaxlen; 124 if_attach(ifp); 125 #if NBPFILTER > 0 126 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 127 #endif 128 } 129 } 130 131 static int 132 looutput(ifp, m, dst, rt) 133 struct ifnet *ifp; 134 register struct mbuf *m; 135 struct sockaddr *dst; 136 register struct rtentry *rt; 137 { 138 if ((m->m_flags & M_PKTHDR) == 0) 139 panic("looutput no HDR"); 140 141 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 142 m_freem(m); 143 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 144 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 145 } 146 ifp->if_opackets++; 147 ifp->if_obytes += m->m_pkthdr.len; 148 #if 1 /* XXX */ 149 switch (dst->sa_family) { 150 case AF_INET: 151 case AF_IPX: 152 case AF_NS: 153 case AF_ISO: 154 case AF_APPLETALK: 155 break; 156 default: 157 printf("looutput: af=%d unexpected", dst->sa_family); 158 m_freem(m); 159 return (EAFNOSUPPORT); 160 } 161 #endif 162 return(if_simloop(ifp, m, dst, 0)); 163 } 164 165 /* 166 * if_simloop() 167 * 168 * This function is to support software emulation of hardware loopback, 169 * i.e., for interfaces with the IFF_SIMPLEX attribute. Since they can't 170 * hear their own broadcasts, we create a copy of the packet that we 171 * would normally receive via a hardware loopback. 172 * 173 * This function expects the packet to include the media header of length hlen. 174 */ 175 176 int 177 if_simloop(ifp, m, dst, hlen) 178 struct ifnet *ifp; 179 register struct mbuf *m; 180 struct sockaddr *dst; 181 int hlen; 182 { 183 int s, isr; 184 register struct ifqueue *ifq = 0; 185 186 if ((m->m_flags & M_PKTHDR) == 0) 187 panic("if_simloop: no HDR"); 188 m->m_pkthdr.rcvif = ifp; 189 #if NBPFILTER > 0 190 /* BPF write needs to be handled specially */ 191 if (dst->sa_family == AF_UNSPEC) { 192 dst->sa_family = *(mtod(m, int *)); 193 m->m_len -= sizeof(int); 194 m->m_pkthdr.len -= sizeof(int); 195 m->m_data += sizeof(int); 196 } 197 198 if (ifp->if_bpf) { 199 struct mbuf m0, *n = m; 200 u_int af = dst->sa_family; 201 202 if (ifp->if_bpf->bif_dlt == DLT_NULL) { 203 /* 204 * We need to prepend the address family as 205 * a four byte field. Cons up a dummy header 206 * to pacify bpf. This is safe because bpf 207 * will only read from the mbuf (i.e., it won't 208 * try to free it or keep a pointer a to it). 209 */ 210 m0.m_next = m; 211 m0.m_len = 4; 212 m0.m_data = (char *)⁡ 213 n = &m0; 214 } 215 bpf_mtap(ifp, n); 216 } 217 #endif 218 219 /* Strip away media header */ 220 if (hlen > 0) { 221 #ifdef __alpha__ 222 /* The alpha doesn't like unaligned data. 223 * We move data down in the first mbuf */ 224 if (hlen & 3) { 225 bcopy(m->m_data + hlen, m->m_data, m->m_len - hlen); 226 m->m_len -= hlen; 227 if (m->m_flags & M_PKTHDR) 228 m->m_pkthdr.len -= hlen; 229 } else 230 #endif 231 m_adj(m, hlen); 232 } 233 234 switch (dst->sa_family) { 235 #ifdef INET 236 case AF_INET: 237 ifq = &ipintrq; 238 isr = NETISR_IP; 239 break; 240 #endif 241 #ifdef IPX 242 case AF_IPX: 243 ifq = &ipxintrq; 244 isr = NETISR_IPX; 245 break; 246 #endif 247 #ifdef NS 248 case AF_NS: 249 ifq = &nsintrq; 250 isr = NETISR_NS; 251 break; 252 #endif 253 #ifdef ISO 254 case AF_ISO: 255 ifq = &clnlintrq; 256 isr = NETISR_ISO; 257 break; 258 #endif 259 #ifdef NETATALK 260 case AF_APPLETALK: 261 ifq = &atintrq2; 262 isr = NETISR_ATALK; 263 break; 264 #endif NETATALK 265 default: 266 printf("if_simloop: can't handle af=%d\n", dst->sa_family); 267 m_freem(m); 268 return (EAFNOSUPPORT); 269 } 270 s = splimp(); 271 if (IF_QFULL(ifq)) { 272 IF_DROP(ifq); 273 m_freem(m); 274 splx(s); 275 return (ENOBUFS); 276 } 277 IF_ENQUEUE(ifq, m); 278 schednetisr(isr); 279 ifp->if_ipackets++; 280 ifp->if_ibytes += m->m_pkthdr.len; 281 splx(s); 282 return (0); 283 } 284 285 /* ARGSUSED */ 286 static void 287 lortrequest(cmd, rt, sa) 288 int cmd; 289 struct rtentry *rt; 290 struct sockaddr *sa; 291 { 292 if (rt) { 293 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 294 /* 295 * For optimal performance, the send and receive buffers 296 * should be at least twice the MTU plus a little more for 297 * overhead. 298 */ 299 rt->rt_rmx.rmx_recvpipe = 300 rt->rt_rmx.rmx_sendpipe = 3 * LOMTU; 301 } 302 } 303 304 /* 305 * Process an ioctl request. 306 */ 307 /* ARGSUSED */ 308 static int 309 loioctl(ifp, cmd, data) 310 register struct ifnet *ifp; 311 u_long cmd; 312 caddr_t data; 313 { 314 register struct ifaddr *ifa; 315 register struct ifreq *ifr = (struct ifreq *)data; 316 register int error = 0; 317 318 switch (cmd) { 319 320 case SIOCSIFADDR: 321 ifp->if_flags |= IFF_UP | IFF_RUNNING; 322 ifa = (struct ifaddr *)data; 323 ifa->ifa_rtrequest = lortrequest; 324 /* 325 * Everything else is done at a higher level. 326 */ 327 break; 328 329 case SIOCADDMULTI: 330 case SIOCDELMULTI: 331 if (ifr == 0) { 332 error = EAFNOSUPPORT; /* XXX */ 333 break; 334 } 335 switch (ifr->ifr_addr.sa_family) { 336 337 #ifdef INET 338 case AF_INET: 339 break; 340 #endif 341 342 default: 343 error = EAFNOSUPPORT; 344 break; 345 } 346 break; 347 348 case SIOCSIFMTU: 349 ifp->if_mtu = ifr->ifr_mtu; 350 break; 351 352 case SIOCSIFFLAGS: 353 break; 354 355 default: 356 error = EINVAL; 357 } 358 return (error); 359 } 360 #endif /* NLOOP > 0 */ 361