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 /* 129 * We need to prepend the address family as 130 * a four byte field. 131 */ 132 uint32_t af = dst->sa_family; 133 134 bpf_ptap(discif.if_bpf, m, &af, sizeof(af)); 135 } 136 m->m_pkthdr.rcvif = ifp; 137 138 ifp->if_opackets++; 139 ifp->if_obytes += m->m_pkthdr.len; 140 141 m_freem(m); 142 return 0; 143 } 144 145 /* ARGSUSED */ 146 static void 147 discrtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info) 148 { 149 if (rt) 150 rt->rt_rmx.rmx_mtu = DSMTU; 151 } 152 153 /* 154 * Process an ioctl request. 155 */ 156 /* ARGSUSED */ 157 static int 158 discioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) 159 { 160 struct ifaddr *ifa; 161 struct ifreq *ifr = (struct ifreq *)data; 162 int error = 0; 163 164 switch (cmd) { 165 166 case SIOCSIFADDR: 167 ifp->if_flags |= IFF_UP; 168 ifa = (struct ifaddr *)data; 169 if (ifa != NULL) 170 ifa->ifa_rtrequest = discrtrequest; 171 /* 172 * Everything else is done at a higher level. 173 */ 174 break; 175 176 case SIOCADDMULTI: 177 case SIOCDELMULTI: 178 if (ifr == NULL) { 179 error = EAFNOSUPPORT; /* XXX */ 180 break; 181 } 182 switch (ifr->ifr_addr.sa_family) { 183 184 #ifdef INET 185 case AF_INET: 186 break; 187 #endif 188 #ifdef INET6 189 case AF_INET6: 190 break; 191 #endif 192 193 default: 194 error = EAFNOSUPPORT; 195 break; 196 } 197 break; 198 199 case SIOCSIFMTU: 200 ifp->if_mtu = ifr->ifr_mtu; 201 break; 202 203 default: 204 error = EINVAL; 205 } 206 return (error); 207 } 208