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 1.11 2004/06/02 14:42:57 eirikn Exp $ 36 */ 37 38 /* 39 * Loopback interface driver for protocol testing and timing. 40 */ 41 #include "use_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 <netproto/ipx/ipx.h> 69 #include <netproto/ipx/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 <netproto/atalk/at.h> 87 #include <netproto/atalk/at_var.h> 88 #endif 89 90 int loioctl (struct ifnet *, u_long, caddr_t, struct ucred *); 91 static void lortrequest (int, struct rtentry *, struct rt_addrinfo *); 92 93 static void loopattach (void *); 94 PSEUDO_SET(loopattach, if_loop); 95 96 int looutput (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 struct ifnet *ifp; 115 int i = 0; 116 117 for (ifp = loif; i < NLOOP; ifp++) { 118 if_initname(ifp, "lo", i++); 119 ifp->if_mtu = LOMTU; 120 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 121 ifp->if_ioctl = loioctl; 122 ifp->if_output = looutput; 123 ifp->if_type = IFT_LOOP; 124 ifp->if_snd.ifq_maxlen = ifqmaxlen; 125 if_attach(ifp); 126 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 127 } 128 } 129 130 int 131 looutput(ifp, m, dst, rt) 132 struct ifnet *ifp; 133 struct mbuf *m; 134 struct sockaddr *dst; 135 struct rtentry *rt; 136 { 137 struct mbuf *n; 138 139 if ((m->m_flags & M_PKTHDR) == 0) 140 panic("looutput no HDR"); 141 142 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 143 m_freem(m); 144 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 145 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 146 } 147 /* 148 * KAME requires that the packet to be contiguous on the 149 * mbuf. We need to make that sure. 150 * this kind of code should be avoided. 151 * 152 * XXX: KAME may no longer need contiguous packets. Once 153 * that has been verified, the following code _should_ be 154 * removed. 155 */ 156 if (m && m->m_next != NULL) { 157 158 n = m_defrag(m, MB_DONTWAIT); 159 160 if (n == NULL) { 161 m_freem(m); 162 return (ENOBUFS); 163 } else { 164 m = n; 165 } 166 } 167 168 ifp->if_opackets++; 169 ifp->if_obytes += m->m_pkthdr.len; 170 #if 1 /* XXX */ 171 switch (dst->sa_family) { 172 case AF_INET: 173 case AF_INET6: 174 case AF_IPX: 175 case AF_NS: 176 case AF_APPLETALK: 177 break; 178 default: 179 printf("looutput: af=%d unexpected\n", dst->sa_family); 180 m_freem(m); 181 return (EAFNOSUPPORT); 182 } 183 #endif 184 return(if_simloop(ifp, m, dst->sa_family, 0)); 185 } 186 187 /* 188 * if_simloop() 189 * 190 * This function is to support software emulation of hardware loopback, 191 * i.e., for interfaces with the IFF_SIMPLEX attribute. Since they can't 192 * hear their own broadcasts, we create a copy of the packet that we 193 * would normally receive via a hardware loopback. 194 * 195 * This function expects the packet to include the media header of length hlen. 196 */ 197 198 int 199 if_simloop(ifp, m, af, hlen) 200 struct ifnet *ifp; 201 struct mbuf *m; 202 int af; 203 int hlen; 204 { 205 int isr; 206 207 KASSERT((m->m_flags & M_PKTHDR) != 0, ("if_simloop: no HDR")); 208 m->m_pkthdr.rcvif = ifp; 209 210 /* BPF write needs to be handled specially */ 211 if (af == AF_UNSPEC) { 212 KASSERT(m->m_len >= sizeof(int), ("if_simloop: m_len")); 213 af = *(mtod(m, int *)); 214 m->m_len -= sizeof(int); 215 m->m_pkthdr.len -= sizeof(int); 216 m->m_data += sizeof(int); 217 } 218 219 /* Let BPF see incoming packet */ 220 if (ifp->if_bpf) { 221 struct mbuf m0, *n = m; 222 223 if (ifp->if_bpf->bif_dlt == DLT_NULL) { 224 /* 225 * We need to prepend the address family as 226 * a four byte field. Cons up a dummy header 227 * to pacify bpf. This is safe because bpf 228 * will only read from the mbuf (i.e., it won't 229 * try to free it or keep a pointer a to it). 230 */ 231 m0.m_next = m; 232 m0.m_len = 4; 233 m0.m_data = (char *)⁡ 234 n = &m0; 235 } 236 bpf_mtap(ifp, n); 237 } 238 239 /* Strip away media header */ 240 if (hlen > 0) { 241 m_adj(m, hlen); 242 #ifdef __alpha__ 243 /* The alpha doesn't like unaligned data. 244 * We move data down in the first mbuf */ 245 if (mtod(m, vm_offset_t) & 3) { 246 KASSERT(hlen >= 3, ("if_simloop: hlen too small")); 247 bcopy(m->m_data, 248 (char *)(mtod(m, vm_offset_t) 249 - (mtod(m, vm_offset_t) & 3)), 250 m->m_len); 251 mtod(m,vm_offset_t) -= (mtod(m, vm_offset_t) & 3); 252 } 253 #endif 254 } 255 256 /* Deliver to upper layer protocol */ 257 switch (af) { 258 #ifdef INET 259 case AF_INET: 260 isr = NETISR_IP; 261 break; 262 #endif 263 #ifdef INET6 264 case AF_INET6: 265 m->m_flags |= M_LOOP; 266 isr = NETISR_IPV6; 267 break; 268 #endif 269 #ifdef IPX 270 case AF_IPX: 271 isr = NETISR_IPX; 272 break; 273 #endif 274 #ifdef NS 275 case AF_NS: 276 isr = NETISR_NS; 277 break; 278 #endif 279 #ifdef NETATALK 280 case AF_APPLETALK: 281 isr = NETISR_ATALK2; 282 break; 283 #endif 284 default: 285 printf("if_simloop: can't handle af=%d\n", af); 286 m_freem(m); 287 return (EAFNOSUPPORT); 288 } 289 290 ifp->if_ipackets++; 291 ifp->if_ibytes += m->m_pkthdr.len; 292 netisr_queue(isr, m); 293 return (0); 294 } 295 296 /* ARGSUSED */ 297 static void 298 lortrequest(cmd, rt, info) 299 int cmd; 300 struct rtentry *rt; 301 struct rt_addrinfo *info; 302 { 303 if (rt) { 304 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 305 /* 306 * For optimal performance, the send and receive buffers 307 * should be at least twice the MTU plus a little more for 308 * overhead. 309 */ 310 rt->rt_rmx.rmx_recvpipe = 311 rt->rt_rmx.rmx_sendpipe = 3 * LOMTU; 312 } 313 } 314 315 /* 316 * Process an ioctl request. 317 */ 318 /* ARGSUSED */ 319 int 320 loioctl(ifp, cmd, data, cr) 321 struct ifnet *ifp; 322 u_long cmd; 323 caddr_t data; 324 struct ucred *cr; 325 { 326 struct ifaddr *ifa; 327 struct ifreq *ifr = (struct ifreq *)data; 328 int error = 0; 329 330 switch (cmd) { 331 332 case SIOCSIFADDR: 333 ifp->if_flags |= IFF_UP | IFF_RUNNING; 334 ifa = (struct ifaddr *)data; 335 ifa->ifa_rtrequest = lortrequest; 336 /* 337 * Everything else is done at a higher level. 338 */ 339 break; 340 341 case SIOCADDMULTI: 342 case SIOCDELMULTI: 343 if (ifr == 0) { 344 error = EAFNOSUPPORT; /* XXX */ 345 break; 346 } 347 switch (ifr->ifr_addr.sa_family) { 348 349 #ifdef INET 350 case AF_INET: 351 break; 352 #endif 353 #ifdef INET6 354 case AF_INET6: 355 break; 356 #endif 357 358 default: 359 error = EAFNOSUPPORT; 360 break; 361 } 362 break; 363 364 case SIOCSIFMTU: 365 ifp->if_mtu = ifr->ifr_mtu; 366 break; 367 368 case SIOCSIFFLAGS: 369 break; 370 371 default: 372 error = EINVAL; 373 } 374 return (error); 375 } 376