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 */ 36 37 /* 38 * Discard interface driver for protocol testing and timing. 39 * (Based on the loopback.) 40 */ 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/module.h> 46 #include <sys/mbuf.h> 47 #include <sys/socket.h> 48 #include <sys/sockio.h> 49 50 #include <net/if.h> 51 #include <net/if_types.h> 52 #include <net/route.h> 53 #include <net/bpf.h> 54 55 #include "opt_inet.h" 56 #include "opt_inet6.h" 57 58 #ifdef TINY_DSMTU 59 #define DSMTU (1024+512) 60 #else 61 #define DSMTU 65532 62 #endif 63 64 static void discattach (void); 65 66 static struct ifnet discif; 67 static int discoutput(struct ifnet *, struct mbuf *, struct sockaddr *, 68 struct rtentry *); 69 static void discrtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info); 70 static int discioctl(struct ifnet *, u_long, caddr_t, struct ucred *); 71 72 /* ARGSUSED */ 73 static void 74 discattach(void) 75 { 76 struct ifnet *ifp = &discif; 77 78 if_initname(ifp, "ds", IF_DUNIT_NONE); 79 ifp->if_mtu = DSMTU; 80 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 81 ifp->if_ioctl = discioctl; 82 ifp->if_output = discoutput; 83 ifp->if_type = IFT_LOOP; 84 ifp->if_hdrlen = 0; 85 ifp->if_addrlen = 0; 86 ifp->if_snd.ifq_maxlen = 20; 87 if_attach(ifp, NULL); 88 bpfattach(ifp, DLT_NULL, sizeof(u_int)); 89 } 90 91 static int 92 disc_modevent(module_t mod, int type, void *data) 93 { 94 switch (type) { 95 case MOD_LOAD: 96 discattach(); 97 break; 98 case MOD_UNLOAD: 99 kprintf("if_disc module unload - not possible for this module type\n"); 100 return EINVAL; 101 } 102 return 0; 103 } 104 105 static moduledata_t disc_mod = { 106 "if_disc", 107 disc_modevent, 108 NULL 109 }; 110 111 DECLARE_MODULE(if_disc, disc_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 112 113 static int 114 discoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 115 struct rtentry *rt) 116 { 117 if ((m->m_flags & M_PKTHDR) == 0) 118 panic("discoutput no HDR"); 119 /* BPF write needs to be handled specially */ 120 if (dst->sa_family == AF_UNSPEC) { 121 dst->sa_family = *(mtod(m, int *)); 122 m->m_len -= sizeof(int); 123 m->m_pkthdr.len -= sizeof(int); 124 m->m_data += sizeof(int); 125 } 126 127 if (discif.if_bpf) { 128 bpf_gettoken(); 129 if (discif.if_bpf) { 130 /* 131 * We need to prepend the address family as 132 * a four byte field. 133 */ 134 uint32_t af = dst->sa_family; 135 136 bpf_ptap(discif.if_bpf, m, &af, sizeof(af)); 137 } 138 bpf_reltoken(); 139 } 140 m->m_pkthdr.rcvif = ifp; 141 142 ifp->if_opackets++; 143 ifp->if_obytes += m->m_pkthdr.len; 144 145 m_freem(m); 146 return 0; 147 } 148 149 /* ARGSUSED */ 150 static void 151 discrtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info) 152 { 153 if (rt) 154 rt->rt_rmx.rmx_mtu = DSMTU; 155 } 156 157 /* 158 * Process an ioctl request. 159 */ 160 /* ARGSUSED */ 161 static int 162 discioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) 163 { 164 struct ifaddr *ifa; 165 struct ifreq *ifr = (struct ifreq *)data; 166 int error = 0; 167 168 switch (cmd) { 169 170 case SIOCSIFADDR: 171 ifp->if_flags |= IFF_UP; 172 ifa = (struct ifaddr *)data; 173 if (ifa != NULL) 174 ifa->ifa_rtrequest = discrtrequest; 175 /* 176 * Everything else is done at a higher level. 177 */ 178 break; 179 180 case SIOCADDMULTI: 181 case SIOCDELMULTI: 182 if (ifr == NULL) { 183 error = EAFNOSUPPORT; /* XXX */ 184 break; 185 } 186 switch (ifr->ifr_addr.sa_family) { 187 188 #ifdef INET 189 case AF_INET: 190 break; 191 #endif 192 #ifdef INET6 193 case AF_INET6: 194 break; 195 #endif 196 197 default: 198 error = EAFNOSUPPORT; 199 break; 200 } 201 break; 202 203 case SIOCSIFMTU: 204 ifp->if_mtu = ifr->ifr_mtu; 205 break; 206 207 default: 208 error = EINVAL; 209 } 210 return (error); 211 } 212