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