1 /* 2 * Copyright (c) 1982, 1986, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)if_loop.c 8.2 (Berkeley) 01/09/95 8 */ 9 10 /* 11 * Loopback interface driver for protocol testing and timing. 12 */ 13 14 #include <sys/param.h> 15 #include <sys/systm.h> 16 #include <sys/kernel.h> 17 #include <sys/mbuf.h> 18 #include <sys/socket.h> 19 #include <sys/errno.h> 20 #include <sys/ioctl.h> 21 #include <sys/time.h> 22 #include <machine/cpu.h> 23 24 #include <net/if.h> 25 #include <net/if_types.h> 26 #include <net/netisr.h> 27 #include <net/route.h> 28 #include <net/bpf.h> 29 30 #ifdef INET 31 #include <netinet/in.h> 32 #include <netinet/in_systm.h> 33 #include <netinet/in_var.h> 34 #include <netinet/ip.h> 35 #endif 36 37 #ifdef NS 38 #include <netns/ns.h> 39 #include <netns/ns_if.h> 40 #endif 41 42 #ifdef ISO 43 #include <netiso/iso.h> 44 #include <netiso/iso_var.h> 45 #endif 46 47 #include "bpfilter.h" 48 49 #define LOMTU (1024+512) 50 51 struct ifnet loif; 52 53 /* ARGSUSED */ 54 void 55 loopattach(n) 56 int n; 57 { 58 register struct ifnet *ifp = &loif; 59 60 #ifdef lint 61 n = n; /* Highlander: there can only be one... */ 62 #endif 63 ifp->if_name = "lo"; 64 ifp->if_mtu = LOMTU; 65 ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST; 66 ifp->if_ioctl = loioctl; 67 ifp->if_output = looutput; 68 ifp->if_type = IFT_LOOP; 69 ifp->if_hdrlen = 0; 70 ifp->if_addrlen = 0; 71 if_attach(ifp); 72 #if NBPFILTER > 0 73 bpfattach(&ifp->if_bpf, ifp, DLT_NULL, sizeof(u_int)); 74 #endif 75 } 76 77 int 78 looutput(ifp, m, dst, rt) 79 struct ifnet *ifp; 80 register struct mbuf *m; 81 struct sockaddr *dst; 82 register struct rtentry *rt; 83 { 84 int s, isr; 85 register struct ifqueue *ifq = 0; 86 87 if ((m->m_flags & M_PKTHDR) == 0) 88 panic("looutput no HDR"); 89 ifp->if_lastchange = time; 90 #if NBPFILTER > 0 91 if (loif.if_bpf) { 92 /* 93 * We need to prepend the address family as 94 * a four byte field. Cons up a dummy header 95 * to pacify bpf. This is safe because bpf 96 * will only read from the mbuf (i.e., it won't 97 * try to free it or keep a pointer a to it). 98 */ 99 struct mbuf m0; 100 u_int af = dst->sa_family; 101 102 m0.m_next = m; 103 m0.m_len = 4; 104 m0.m_data = (char *)⁡ 105 106 bpf_mtap(loif.if_bpf, &m0); 107 } 108 #endif 109 m->m_pkthdr.rcvif = ifp; 110 111 if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) { 112 m_freem(m); 113 return (rt->rt_flags & RTF_BLACKHOLE ? 0 : 114 rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 115 } 116 ifp->if_opackets++; 117 ifp->if_obytes += m->m_pkthdr.len; 118 switch (dst->sa_family) { 119 120 #ifdef INET 121 case AF_INET: 122 ifq = &ipintrq; 123 isr = NETISR_IP; 124 break; 125 #endif 126 #ifdef NS 127 case AF_NS: 128 ifq = &nsintrq; 129 isr = NETISR_NS; 130 break; 131 #endif 132 #ifdef ISO 133 case AF_ISO: 134 ifq = &clnlintrq; 135 isr = NETISR_ISO; 136 break; 137 #endif 138 default: 139 printf("lo%d: can't handle af%d\n", ifp->if_unit, 140 dst->sa_family); 141 m_freem(m); 142 return (EAFNOSUPPORT); 143 } 144 s = splimp(); 145 if (IF_QFULL(ifq)) { 146 IF_DROP(ifq); 147 m_freem(m); 148 splx(s); 149 return (ENOBUFS); 150 } 151 IF_ENQUEUE(ifq, m); 152 schednetisr(isr); 153 ifp->if_ipackets++; 154 ifp->if_ibytes += m->m_pkthdr.len; 155 splx(s); 156 return (0); 157 } 158 159 /* ARGSUSED */ 160 void 161 lortrequest(cmd, rt, sa) 162 int cmd; 163 struct rtentry *rt; 164 struct sockaddr *sa; 165 { 166 167 if (rt) 168 rt->rt_rmx.rmx_mtu = LOMTU; 169 } 170 171 /* 172 * Process an ioctl request. 173 */ 174 /* ARGSUSED */ 175 int 176 loioctl(ifp, cmd, data) 177 register struct ifnet *ifp; 178 u_long cmd; 179 caddr_t data; 180 { 181 register struct ifaddr *ifa; 182 register struct ifreq *ifr; 183 register int error = 0; 184 185 switch (cmd) { 186 187 case SIOCSIFADDR: 188 ifp->if_flags |= IFF_UP; 189 ifa = (struct ifaddr *)data; 190 if (ifa != 0 && ifa->ifa_addr->sa_family == AF_ISO) 191 ifa->ifa_rtrequest = lortrequest; 192 /* 193 * Everything else is done at a higher level. 194 */ 195 break; 196 197 case SIOCADDMULTI: 198 case SIOCDELMULTI: 199 ifr = (struct ifreq *)data; 200 if (ifr == 0) { 201 error = EAFNOSUPPORT; /* XXX */ 202 break; 203 } 204 switch (ifr->ifr_addr.sa_family) { 205 206 #ifdef INET 207 case AF_INET: 208 break; 209 #endif 210 211 default: 212 error = EAFNOSUPPORT; 213 break; 214 } 215 break; 216 217 default: 218 error = EINVAL; 219 } 220 return (error); 221 } 222