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 * $FreeBSD: src/sys/net/if_loop.c,v 1.47.2.8 2003/06/01 01:46:11 silby Exp $ 35 * $DragonFly: src/sys/net/if_loop.c,v 1.2 2003/06/17 04:28:48 dillon Exp $ 36 */ 37 38 /* 39 * Loopback interface driver for protocol testing and timing. 40 */ 41 #include "loop.h" 42 43 #include "opt_atalk.h" 44 #include "opt_inet.h" 45 #include "opt_inet6.h" 46 #include "opt_ipx.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/kernel.h> 51 #include <sys/mbuf.h> 52 #include <sys/socket.h> 53 #include <sys/sockio.h> 54 55 #include <net/if.h> 56 #include <net/if_types.h> 57 #include <net/netisr.h> 58 #include <net/route.h> 59 #include <net/bpf.h> 60 #include <net/bpfdesc.h> 61 62 #ifdef INET 63 #include <netinet/in.h> 64 #include <netinet/in_var.h> 65 #endif 66 67 #ifdef IPX 68 #include <netipx/ipx.h> 69 #include <netipx/ipx_if.h> 70 #endif 71 72 #ifdef INET6 73 #ifndef INET 74 #include <netinet/in.h> 75 #endif 76 #include <netinet6/in6_var.h> 77 #include <netinet/ip6.h> 78 #endif 79 80 #ifdef NS 81 #include <netns/ns.h> 82 #include <netns/ns_if.h> 83 #endif 84 85 #ifdef NETATALK 86 #include <netatalk/at.h> 87 #include <netatalk/at_var.h> 88 #endif NETATALK 89 90 int loioctl __P((struct ifnet *, u_long, caddr_t)); 91 static void lortrequest __P((int, struct rtentry *, struct rt_addrinfo *)); 92 93 static void loopattach __P((void *)); 94 PSEUDO_SET(loopattach, if_loop); 95 96 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 #elif defined(LARGE_LOMTU) 102 #define LOMTU 131072 103 #else 104 #define LOMTU 16384 105 #endif 106 107 struct ifnet loif[NLOOP]; 108 109 /* ARGSUSED */ 110 static void 111 loopattach(dummy) 112 void *dummy; 113 { 114 register struct ifnet *ifp; 115 register int i = 0; 116 117 for (ifp = loif; i < NLOOP; ifp++) { 118 ifp->if_name = "lo"; 119 ifp->if_unit = i++; 120 ifp->if_mtu = LOMTU; 121 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 122 ifp->if_ioctl = loioctl; 123 ifp->if_output = looutput; 124 ifp->if_type = IFT_LOOP; 125 ifp->if_snd.ifq_maxlen = ifqmaxlen; 126 if_attach(ifp); 127 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 128 } 129 } 130 131 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 struct mbuf *n; 139 140 if ((m->m_flags & M_PKTHDR) == 0) 141 panic("looutput no HDR"); 142 143 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 144 m_freem(m); 145 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 146 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 147 } 148 /* 149 * KAME requires that the packet to be contiguous on the 150 * mbuf. We need to make that sure. 151 * this kind of code should be avoided. 152 * 153 * XXX: KAME may no longer need contiguous packets. Once 154 * that has been verified, the following code _should_ be 155 * removed. 156 */ 157 if (m && m->m_next != NULL) { 158 159 n = m_defrag(m, M_DONTWAIT); 160 161 if (n == NULL) { 162 m_freem(m); 163 return (ENOBUFS); 164 } else { 165 m = n; 166 } 167 } 168 169 ifp->if_opackets++; 170 ifp->if_obytes += m->m_pkthdr.len; 171 #if 1 /* XXX */ 172 switch (dst->sa_family) { 173 case AF_INET: 174 case AF_INET6: 175 case AF_IPX: 176 case AF_NS: 177 case AF_APPLETALK: 178 break; 179 default: 180 printf("looutput: af=%d unexpected\n", dst->sa_family); 181 m_freem(m); 182 return (EAFNOSUPPORT); 183 } 184 #endif 185 return(if_simloop(ifp, m, dst->sa_family, 0)); 186 } 187 188 /* 189 * if_simloop() 190 * 191 * This function is to support software emulation of hardware loopback, 192 * i.e., for interfaces with the IFF_SIMPLEX attribute. Since they can't 193 * hear their own broadcasts, we create a copy of the packet that we 194 * would normally receive via a hardware loopback. 195 * 196 * This function expects the packet to include the media header of length hlen. 197 */ 198 199 int 200 if_simloop(ifp, m, af, hlen) 201 struct ifnet *ifp; 202 struct mbuf *m; 203 int af; 204 int hlen; 205 { 206 int s, isr; 207 register struct ifqueue *ifq = 0; 208 209 KASSERT((m->m_flags & M_PKTHDR) != 0, ("if_simloop: no HDR")); 210 m->m_pkthdr.rcvif = ifp; 211 212 /* BPF write needs to be handled specially */ 213 if (af == AF_UNSPEC) { 214 KASSERT(m->m_len >= sizeof(int), ("if_simloop: m_len")); 215 af = *(mtod(m, int *)); 216 m->m_len -= sizeof(int); 217 m->m_pkthdr.len -= sizeof(int); 218 m->m_data += sizeof(int); 219 } 220 221 /* Let BPF see incoming packet */ 222 if (ifp->if_bpf) { 223 struct mbuf m0, *n = m; 224 225 if (ifp->if_bpf->bif_dlt == DLT_NULL) { 226 /* 227 * We need to prepend the address family as 228 * a four byte field. Cons up a dummy header 229 * to pacify bpf. This is safe because bpf 230 * will only read from the mbuf (i.e., it won't 231 * try to free it or keep a pointer a to it). 232 */ 233 m0.m_next = m; 234 m0.m_len = 4; 235 m0.m_data = (char *)⁡ 236 n = &m0; 237 } 238 bpf_mtap(ifp, n); 239 } 240 241 /* Strip away media header */ 242 if (hlen > 0) { 243 m_adj(m, hlen); 244 #ifdef __alpha__ 245 /* The alpha doesn't like unaligned data. 246 * We move data down in the first mbuf */ 247 if (mtod(m, vm_offset_t) & 3) { 248 KASSERT(hlen >= 3, ("if_simloop: hlen too small")); 249 bcopy(m->m_data, 250 (char *)(mtod(m, vm_offset_t) 251 - (mtod(m, vm_offset_t) & 3)), 252 m->m_len); 253 mtod(m,vm_offset_t) -= (mtod(m, vm_offset_t) & 3); 254 } 255 #endif 256 } 257 258 /* Deliver to upper layer protocol */ 259 switch (af) { 260 #ifdef INET 261 case AF_INET: 262 ifq = &ipintrq; 263 isr = NETISR_IP; 264 break; 265 #endif 266 #ifdef INET6 267 case AF_INET6: 268 m->m_flags |= M_LOOP; 269 ifq = &ip6intrq; 270 isr = NETISR_IPV6; 271 break; 272 #endif 273 #ifdef IPX 274 case AF_IPX: 275 ifq = &ipxintrq; 276 isr = NETISR_IPX; 277 break; 278 #endif 279 #ifdef NS 280 case AF_NS: 281 ifq = &nsintrq; 282 isr = NETISR_NS; 283 break; 284 #endif 285 #ifdef NETATALK 286 case AF_APPLETALK: 287 ifq = &atintrq2; 288 isr = NETISR_ATALK; 289 break; 290 #endif NETATALK 291 default: 292 printf("if_simloop: can't handle af=%d\n", af); 293 m_freem(m); 294 return (EAFNOSUPPORT); 295 } 296 s = splimp(); 297 if (IF_QFULL(ifq)) { 298 IF_DROP(ifq); 299 m_freem(m); 300 splx(s); 301 return (ENOBUFS); 302 } 303 IF_ENQUEUE(ifq, m); 304 schednetisr(isr); 305 ifp->if_ipackets++; 306 ifp->if_ibytes += m->m_pkthdr.len; 307 splx(s); 308 return (0); 309 } 310 311 /* ARGSUSED */ 312 static void 313 lortrequest(cmd, rt, info) 314 int cmd; 315 struct rtentry *rt; 316 struct rt_addrinfo *info; 317 { 318 if (rt) { 319 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 320 /* 321 * For optimal performance, the send and receive buffers 322 * should be at least twice the MTU plus a little more for 323 * overhead. 324 */ 325 rt->rt_rmx.rmx_recvpipe = 326 rt->rt_rmx.rmx_sendpipe = 3 * LOMTU; 327 } 328 } 329 330 /* 331 * Process an ioctl request. 332 */ 333 /* ARGSUSED */ 334 int 335 loioctl(ifp, cmd, data) 336 register struct ifnet *ifp; 337 u_long cmd; 338 caddr_t data; 339 { 340 register struct ifaddr *ifa; 341 register struct ifreq *ifr = (struct ifreq *)data; 342 register int error = 0; 343 344 switch (cmd) { 345 346 case SIOCSIFADDR: 347 ifp->if_flags |= IFF_UP | IFF_RUNNING; 348 ifa = (struct ifaddr *)data; 349 ifa->ifa_rtrequest = lortrequest; 350 /* 351 * Everything else is done at a higher level. 352 */ 353 break; 354 355 case SIOCADDMULTI: 356 case SIOCDELMULTI: 357 if (ifr == 0) { 358 error = EAFNOSUPPORT; /* XXX */ 359 break; 360 } 361 switch (ifr->ifr_addr.sa_family) { 362 363 #ifdef INET 364 case AF_INET: 365 break; 366 #endif 367 #ifdef INET6 368 case AF_INET6: 369 break; 370 #endif 371 372 default: 373 error = EAFNOSUPPORT; 374 break; 375 } 376 break; 377 378 case SIOCSIFMTU: 379 ifp->if_mtu = ifr->ifr_mtu; 380 break; 381 382 case SIOCSIFFLAGS: 383 break; 384 385 default: 386 error = EINVAL; 387 } 388 return (error); 389 } 390