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/ifq_var.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 (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, struct ucred *); 72 73 /* ARGSUSED */ 74 static void 75 discattach(void) 76 { 77 struct ifnet *ifp = &discif; 78 79 if_initname(ifp, "ds", IF_DUNIT_NONE); 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 ifq_set_maxlen(&ifp->if_snd, 20); 88 if_attach(ifp, NULL); 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 kprintf("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(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst, 116 struct rtentry *rt) 117 { 118 if ((m->m_flags & M_PKTHDR) == 0) 119 panic("discoutput no HDR"); 120 /* BPF write needs to be handled specially */ 121 if (dst->sa_family == AF_UNSPEC) { 122 dst->sa_family = *(mtod(m, int *)); 123 m->m_len -= sizeof(int); 124 m->m_pkthdr.len -= sizeof(int); 125 m->m_data += sizeof(int); 126 } 127 128 if (discif.if_bpf) { 129 bpf_gettoken(); 130 if (discif.if_bpf) { 131 /* 132 * We need to prepend the address family as 133 * a four byte field. 134 */ 135 uint32_t af = dst->sa_family; 136 137 bpf_ptap(discif.if_bpf, m, &af, sizeof(af)); 138 } 139 bpf_reltoken(); 140 } 141 m->m_pkthdr.rcvif = ifp; 142 143 IFNET_STAT_INC(ifp, opackets, 1); 144 IFNET_STAT_INC(ifp, obytes, m->m_pkthdr.len); 145 146 m_freem(m); 147 return 0; 148 } 149 150 /* ARGSUSED */ 151 static void 152 discrtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info) 153 { 154 if (rt) 155 rt->rt_rmx.rmx_mtu = DSMTU; 156 } 157 158 /* 159 * Process an ioctl request. 160 */ 161 /* ARGSUSED */ 162 static int 163 discioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) 164 { 165 struct ifaddr *ifa; 166 struct ifreq *ifr = (struct ifreq *)data; 167 int error = 0; 168 169 switch (cmd) { 170 171 case SIOCSIFADDR: 172 ifp->if_flags |= IFF_UP; 173 ifa = (struct ifaddr *)data; 174 if (ifa != NULL) 175 ifa->ifa_rtrequest = discrtrequest; 176 /* 177 * Everything else is done at a higher level. 178 */ 179 break; 180 181 case SIOCADDMULTI: 182 case SIOCDELMULTI: 183 if (ifr == NULL) { 184 error = EAFNOSUPPORT; /* XXX */ 185 break; 186 } 187 switch (ifr->ifr_addr.sa_family) { 188 189 #ifdef INET 190 case AF_INET: 191 break; 192 #endif 193 #ifdef INET6 194 case AF_INET6: 195 break; 196 #endif 197 198 default: 199 error = EAFNOSUPPORT; 200 break; 201 } 202 break; 203 204 case SIOCSIFMTU: 205 ifp->if_mtu = ifr->ifr_mtu; 206 break; 207 208 default: 209 error = EINVAL; 210 } 211 return (error); 212 } 213