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 * $FreeBSD$ 35 */ 36 37 /* 38 * Loopback interface driver for protocol testing and timing. 39 */ 40 #include "loop.h" 41 42 #include "opt_atalk.h" 43 #include "opt_inet.h" 44 #include "opt_inet6.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 INET6 71 #ifndef INET 72 #include <netinet/in.h> 73 #endif 74 #include <netinet6/in6_var.h> 75 #include <netinet/ip6.h> 76 #endif 77 78 #ifdef NS 79 #include <netns/ns.h> 80 #include <netns/ns_if.h> 81 #endif 82 83 #ifdef NETATALK 84 #include <netatalk/at.h> 85 #include <netatalk/at_var.h> 86 #endif NETATALK 87 88 int loioctl __P((struct ifnet *, u_long, caddr_t)); 89 static void lortrequest __P((int, struct rtentry *, struct sockaddr *)); 90 91 static void loopattach __P((void *)); 92 PSEUDO_SET(loopattach, if_loop); 93 94 int looutput __P((struct ifnet *ifp, 95 struct mbuf *m, struct sockaddr *dst, struct rtentry *rt)); 96 97 #ifdef TINY_LOMTU 98 #define LOMTU (1024+512) 99 #elif defined(LARGE_LOMTU) 100 #define LOMTU 131072 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 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 126 } 127 } 128 129 int 130 looutput(ifp, m, dst, rt) 131 struct ifnet *ifp; 132 register struct mbuf *m; 133 struct sockaddr *dst; 134 register struct rtentry *rt; 135 { 136 if ((m->m_flags & M_PKTHDR) == 0) 137 panic("looutput no HDR"); 138 139 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 140 m_freem(m); 141 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 142 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 143 } 144 /* 145 * KAME requires that the packet to be contiguous on the 146 * mbuf. We need to make that sure. 147 * this kind of code should be avoided. 148 * XXX: fails to join if interface MTU > MCLBYTES. jumbogram? 149 */ 150 if (m && m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) { 151 struct mbuf *n; 152 153 MGETHDR(n, M_DONTWAIT, MT_HEADER); 154 if (!n) 155 goto contiguousfail; 156 MCLGET(n, M_DONTWAIT); 157 if (! (n->m_flags & M_EXT)) { 158 m_freem(n); 159 goto contiguousfail; 160 } 161 162 m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t)); 163 n->m_pkthdr = m->m_pkthdr; 164 n->m_len = m->m_pkthdr.len; 165 m_freem(m); 166 m = n; 167 } 168 if (0) { 169 contiguousfail: 170 printf("looutput: mbuf allocation failed\n"); 171 } 172 173 ifp->if_opackets++; 174 ifp->if_obytes += m->m_pkthdr.len; 175 #if 1 /* XXX */ 176 switch (dst->sa_family) { 177 case AF_INET: 178 case AF_INET6: 179 case AF_IPX: 180 case AF_NS: 181 case AF_APPLETALK: 182 break; 183 default: 184 printf("looutput: af=%d unexpected\n", dst->sa_family); 185 m_freem(m); 186 return (EAFNOSUPPORT); 187 } 188 #endif 189 return(if_simloop(ifp, m, dst->sa_family, 0)); 190 } 191 192 /* 193 * if_simloop() 194 * 195 * This function is to support software emulation of hardware loopback, 196 * i.e., for interfaces with the IFF_SIMPLEX attribute. Since they can't 197 * hear their own broadcasts, we create a copy of the packet that we 198 * would normally receive via a hardware loopback. 199 * 200 * This function expects the packet to include the media header of length hlen. 201 */ 202 203 int 204 if_simloop(ifp, m, af, hlen) 205 struct ifnet *ifp; 206 register struct mbuf *m; 207 int af; 208 int hlen; 209 { 210 int s, isr; 211 register struct ifqueue *ifq = 0; 212 213 KASSERT((m->m_flags & M_PKTHDR) != 0, ("if_simloop: no HDR")); 214 m->m_pkthdr.rcvif = ifp; 215 216 /* BPF write needs to be handled specially */ 217 if (af == AF_UNSPEC) { 218 KASSERT(m->m_len >= sizeof(int), ("if_simloop: m_len")); 219 af = *(mtod(m, int *)); 220 m->m_len -= sizeof(int); 221 m->m_pkthdr.len -= sizeof(int); 222 m->m_data += sizeof(int); 223 } 224 225 /* Let BPF see incoming packet */ 226 if (ifp->if_bpf) { 227 struct mbuf m0, *n = m; 228 229 /* 230 * We need to prepend the address family as 231 * a four byte field. Cons up a dummy header 232 * to pacify bpf. This is safe because bpf 233 * will only read from the mbuf (i.e., it won't 234 * try to free it or keep a pointer a to it). 235 */ 236 m0.m_next = m; 237 m0.m_len = 4; 238 m0.m_data = (char *)⁡ 239 n = &m0; 240 bpf_mtap(ifp, n); 241 } 242 243 /* Strip away media header */ 244 if (hlen > 0) { 245 m_adj(m, hlen); 246 #ifdef __alpha__ 247 /* The alpha doesn't like unaligned data. 248 * We move data down in the first mbuf */ 249 if (mtod(m, vm_offset_t) & 3) { 250 KASSERT(hlen >= 3, ("if_simloop: hlen too small")); 251 bcopy(m->m_data, 252 (char *)(mtod(m, vm_offset_t) 253 - (mtod(m, vm_offset_t) & 3)), 254 m->m_len); 255 mtod(m,vm_offset_t) -= (mtod(m, vm_offset_t) & 3); 256 } 257 #endif 258 } 259 260 /* Deliver to upper layer protocol */ 261 switch (af) { 262 #ifdef INET 263 case AF_INET: 264 ifq = &ipintrq; 265 isr = NETISR_IP; 266 break; 267 #endif 268 #ifdef INET6 269 case AF_INET6: 270 m->m_flags |= M_LOOP; 271 ifq = &ip6intrq; 272 isr = NETISR_IPV6; 273 break; 274 #endif 275 #ifdef IPX 276 case AF_IPX: 277 ifq = &ipxintrq; 278 isr = NETISR_IPX; 279 break; 280 #endif 281 #ifdef NS 282 case AF_NS: 283 ifq = &nsintrq; 284 isr = NETISR_NS; 285 break; 286 #endif 287 #ifdef NETATALK 288 case AF_APPLETALK: 289 ifq = &atintrq2; 290 isr = NETISR_ATALK; 291 break; 292 #endif NETATALK 293 default: 294 printf("if_simloop: can't handle af=%d\n", af); 295 m_freem(m); 296 return (EAFNOSUPPORT); 297 } 298 s = splimp(); 299 if (IF_QFULL(ifq)) { 300 IF_DROP(ifq); 301 m_freem(m); 302 splx(s); 303 return (ENOBUFS); 304 } 305 IF_ENQUEUE(ifq, m); 306 schednetisr(isr); 307 ifp->if_ipackets++; 308 ifp->if_ibytes += m->m_pkthdr.len; 309 splx(s); 310 return (0); 311 } 312 313 /* ARGSUSED */ 314 static void 315 lortrequest(cmd, rt, sa) 316 int cmd; 317 struct rtentry *rt; 318 struct sockaddr *sa; 319 { 320 if (rt) { 321 rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */ 322 /* 323 * For optimal performance, the send and receive buffers 324 * should be at least twice the MTU plus a little more for 325 * overhead. 326 */ 327 rt->rt_rmx.rmx_recvpipe = 328 rt->rt_rmx.rmx_sendpipe = 3 * LOMTU; 329 } 330 } 331 332 /* 333 * Process an ioctl request. 334 */ 335 /* ARGSUSED */ 336 int 337 loioctl(ifp, cmd, data) 338 register struct ifnet *ifp; 339 u_long cmd; 340 caddr_t data; 341 { 342 register struct ifaddr *ifa; 343 register struct ifreq *ifr = (struct ifreq *)data; 344 register int error = 0; 345 346 switch (cmd) { 347 348 case SIOCSIFADDR: 349 ifp->if_flags |= IFF_UP | IFF_RUNNING; 350 ifa = (struct ifaddr *)data; 351 ifa->ifa_rtrequest = lortrequest; 352 /* 353 * Everything else is done at a higher level. 354 */ 355 break; 356 357 case SIOCADDMULTI: 358 case SIOCDELMULTI: 359 if (ifr == 0) { 360 error = EAFNOSUPPORT; /* XXX */ 361 break; 362 } 363 switch (ifr->ifr_addr.sa_family) { 364 365 #ifdef INET 366 case AF_INET: 367 break; 368 #endif 369 #ifdef INET6 370 case AF_INET6: 371 break; 372 #endif 373 374 default: 375 error = EAFNOSUPPORT; 376 break; 377 } 378 break; 379 380 case SIOCSIFMTU: 381 ifp->if_mtu = ifr->ifr_mtu; 382 break; 383 384 case SIOCSIFFLAGS: 385 break; 386 387 default: 388 error = EINVAL; 389 } 390 return (error); 391 } 392