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 * From: @(#)if_loop.c 8.1 (Berkeley) 6/10/93 34 * $FreeBSD: src/sys/net/if_disc.c,v 1.26.2.2 2001/12/20 10:30:16 ru Exp $ 35 * $DragonFly: src/sys/net/disc/if_disc.c,v 1.2 2003/06/17 04:28:47 dillon Exp $ 36 */ 37 38 /* 39 * Discard interface driver for protocol testing and timing. 40 * (Based on the loopback.) 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/kernel.h> 46 #include <sys/module.h> 47 #include <sys/mbuf.h> 48 #include <sys/socket.h> 49 #include <sys/sockio.h> 50 51 #include <net/if.h> 52 #include <net/if_types.h> 53 #include <net/route.h> 54 #include <net/bpf.h> 55 56 #include "opt_inet.h" 57 #include "opt_inet6.h" 58 59 #ifdef TINY_DSMTU 60 #define DSMTU (1024+512) 61 #else 62 #define DSMTU 65532 63 #endif 64 65 static void discattach __P((void)); 66 67 static struct ifnet discif; 68 static int discoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 69 struct rtentry *); 70 static void discrtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info); 71 static int discioctl(struct ifnet *, u_long, caddr_t); 72 73 /* ARGSUSED */ 74 static void 75 discattach() 76 { 77 register struct ifnet *ifp = &discif; 78 79 ifp->if_name = "ds"; 80 ifp->if_mtu = DSMTU; 81 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 82 ifp->if_ioctl = discioctl; 83 ifp->if_output = discoutput; 84 ifp->if_type = IFT_LOOP; 85 ifp->if_hdrlen = 0; 86 ifp->if_addrlen = 0; 87 ifp->if_snd.ifq_maxlen = 20; 88 if_attach(ifp); 89 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 90 } 91 92 static int 93 disc_modevent(module_t mod, int type, void *data) 94 { 95 switch (type) { 96 case MOD_LOAD: 97 discattach(); 98 break; 99 case MOD_UNLOAD: 100 printf("if_disc module unload - not possible for this module type\n"); 101 return EINVAL; 102 } 103 return 0; 104 } 105 106 static moduledata_t disc_mod = { 107 "if_disc", 108 disc_modevent, 109 NULL 110 }; 111 112 DECLARE_MODULE(if_disc, disc_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 113 114 static int 115 discoutput(ifp, m, dst, rt) 116 struct ifnet *ifp; 117 register struct mbuf *m; 118 struct sockaddr *dst; 119 register struct rtentry *rt; 120 { 121 if ((m->m_flags & M_PKTHDR) == 0) 122 panic("discoutput no HDR"); 123 /* BPF write needs to be handled specially */ 124 if (dst->sa_family == AF_UNSPEC) { 125 dst->sa_family = *(mtod(m, int *)); 126 m->m_len -= sizeof(int); 127 m->m_pkthdr.len -= sizeof(int); 128 m->m_data += sizeof(int); 129 } 130 131 if (discif.if_bpf) { 132 /* 133 * We need to prepend the address family as 134 * a four byte field. Cons up a dummy header 135 * to pacify bpf. This is safe because bpf 136 * will only read from the mbuf (i.e., it won't 137 * try to free it or keep a pointer a to it). 138 */ 139 struct mbuf m0; 140 u_int af = dst->sa_family; 141 142 m0.m_next = m; 143 m0.m_len = 4; 144 m0.m_data = (char *)⁡ 145 146 bpf_mtap(&discif, &m0); 147 } 148 m->m_pkthdr.rcvif = ifp; 149 150 ifp->if_opackets++; 151 ifp->if_obytes += m->m_pkthdr.len; 152 153 m_freem(m); 154 return 0; 155 } 156 157 /* ARGSUSED */ 158 static void 159 discrtrequest(cmd, rt, info) 160 int cmd; 161 struct rtentry *rt; 162 struct rt_addrinfo *info; 163 { 164 if (rt) 165 rt->rt_rmx.rmx_mtu = DSMTU; 166 } 167 168 /* 169 * Process an ioctl request. 170 */ 171 /* ARGSUSED */ 172 static int 173 discioctl(ifp, cmd, data) 174 register struct ifnet *ifp; 175 u_long cmd; 176 caddr_t data; 177 { 178 register struct ifaddr *ifa; 179 register struct ifreq *ifr = (struct ifreq *)data; 180 register int error = 0; 181 182 switch (cmd) { 183 184 case SIOCSIFADDR: 185 ifp->if_flags |= IFF_UP; 186 ifa = (struct ifaddr *)data; 187 if (ifa != 0) 188 ifa->ifa_rtrequest = discrtrequest; 189 /* 190 * Everything else is done at a higher level. 191 */ 192 break; 193 194 case SIOCADDMULTI: 195 case SIOCDELMULTI: 196 if (ifr == 0) { 197 error = EAFNOSUPPORT; /* XXX */ 198 break; 199 } 200 switch (ifr->ifr_addr.sa_family) { 201 202 #ifdef INET 203 case AF_INET: 204 break; 205 #endif 206 #ifdef INET6 207 case AF_INET6: 208 break; 209 #endif 210 211 default: 212 error = EAFNOSUPPORT; 213 break; 214 } 215 break; 216 217 case SIOCSIFMTU: 218 ifp->if_mtu = ifr->ifr_mtu; 219 break; 220 221 default: 222 error = EINVAL; 223 } 224 return (error); 225 } 226