1 /* $OpenBSD: if_pair.c,v 1.17 2021/01/13 01:57:31 kn Exp $ */ 2 3 /* 4 * Copyright (c) 2015 Reyk Floeter <reyk@openbsd.org> 5 * Copyright (c) 2009 Theo de Raadt <deraadt@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/param.h> 21 #include <sys/systm.h> 22 #include <sys/mbuf.h> 23 #include <sys/socket.h> 24 #include <sys/sockio.h> 25 #include <sys/ioctl.h> 26 27 #include <net/if.h> 28 #include <net/if_media.h> 29 30 #include <netinet/in.h> 31 #include <netinet/if_ether.h> 32 33 #include "bpfilter.h" 34 #if NBPFILTER > 0 35 #include <net/bpf.h> 36 #endif 37 38 void pairattach(int); 39 int pairioctl(struct ifnet *, u_long, caddr_t); 40 void pairstart(struct ifqueue *); 41 int pair_clone_create(struct if_clone *, int); 42 int pair_clone_destroy(struct ifnet *); 43 int pair_media_change(struct ifnet *); 44 void pair_media_status(struct ifnet *, struct ifmediareq *); 45 void pair_link_state(struct ifnet *); 46 47 struct pair_softc { 48 struct arpcom sc_ac; 49 struct ifmedia sc_media; 50 unsigned int sc_pairedif; 51 }; 52 53 struct if_clone pair_cloner = 54 IF_CLONE_INITIALIZER("pair", pair_clone_create, pair_clone_destroy); 55 56 int 57 pair_media_change(struct ifnet *ifp) 58 { 59 return (0); 60 } 61 62 void 63 pair_media_status(struct ifnet *ifp, struct ifmediareq *imr) 64 { 65 struct pair_softc *sc = ifp->if_softc; 66 struct ifnet *pairedifp; 67 68 imr->ifm_active = IFM_ETHER | IFM_AUTO; 69 70 if ((pairedifp = if_get(sc->sc_pairedif)) == NULL) { 71 imr->ifm_status = 0; 72 return; 73 } 74 if_put(pairedifp); 75 76 imr->ifm_status = IFM_AVALID | IFM_ACTIVE; 77 } 78 79 void 80 pair_link_state(struct ifnet *ifp) 81 { 82 struct pair_softc *sc = ifp->if_softc; 83 struct ifnet *pairedifp; 84 unsigned int link_state; 85 86 /* The pair state is determined by the paired interface */ 87 if ((pairedifp = if_get(sc->sc_pairedif)) != NULL) { 88 link_state = LINK_STATE_UP; 89 if_put(pairedifp); 90 } else 91 link_state = LINK_STATE_DOWN; 92 93 if (ifp->if_link_state != link_state) { 94 ifp->if_link_state = link_state; 95 if_link_state_change(ifp); 96 } 97 } 98 99 void 100 pairattach(int npair) 101 { 102 if_clone_attach(&pair_cloner); 103 } 104 105 int 106 pair_clone_create(struct if_clone *ifc, int unit) 107 { 108 struct ifnet *ifp; 109 struct pair_softc *sc; 110 111 sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO); 112 ifp = &sc->sc_ac.ac_if; 113 snprintf(ifp->if_xname, sizeof ifp->if_xname, "pair%d", unit); 114 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 115 ether_fakeaddr(ifp); 116 117 ifp->if_softc = sc; 118 ifp->if_ioctl = pairioctl; 119 ifp->if_qstart = pairstart; 120 ifp->if_xflags = IFXF_CLONED | IFXF_MPSAFE; 121 122 ifp->if_hardmtu = ETHER_MAX_HARDMTU_LEN; 123 ifp->if_capabilities = IFCAP_VLAN_MTU; 124 125 ifmedia_init(&sc->sc_media, 0, pair_media_change, 126 pair_media_status); 127 ifmedia_add(&sc->sc_media, IFM_ETHER | IFM_AUTO, 0, NULL); 128 ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_AUTO); 129 130 if_attach(ifp); 131 ether_ifattach(ifp); 132 133 pair_link_state(ifp); 134 135 return (0); 136 } 137 138 int 139 pair_clone_destroy(struct ifnet *ifp) 140 { 141 struct pair_softc *sc = ifp->if_softc; 142 struct ifnet *pairedifp; 143 struct pair_softc *dstsc = ifp->if_softc; 144 145 if ((pairedifp = if_get(sc->sc_pairedif)) != NULL) { 146 dstsc = pairedifp->if_softc; 147 dstsc->sc_pairedif = 0; 148 pair_link_state(pairedifp); 149 if_put(pairedifp); 150 } 151 152 ifmedia_delete_instance(&sc->sc_media, IFM_INST_ANY); 153 ether_ifdetach(ifp); 154 if_detach(ifp); 155 free(sc, M_DEVBUF, sizeof(*sc)); 156 157 return (0); 158 } 159 160 void 161 pairstart(struct ifqueue *ifq) 162 { 163 struct ifnet *ifp = ifq->ifq_if; 164 struct pair_softc *sc = (struct pair_softc *)ifp->if_softc; 165 struct mbuf_list ml = MBUF_LIST_INITIALIZER(); 166 struct ifnet *pairedifp; 167 struct mbuf *m; 168 169 pairedifp = if_get(sc->sc_pairedif); 170 171 while ((m = ifq_dequeue(ifq)) != NULL) { 172 #if NBPFILTER > 0 173 if (ifp->if_bpf) 174 bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT); 175 #endif /* NBPFILTER > 0 */ 176 177 if (pairedifp != NULL) { 178 if (m->m_flags & M_PKTHDR) 179 m_resethdr(m); 180 ml_enqueue(&ml, m); 181 } else 182 m_freem(m); 183 } 184 185 if (pairedifp != NULL) { 186 if_input(pairedifp, &ml); 187 if_put(pairedifp); 188 } 189 } 190 191 int 192 pairioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 193 { 194 struct pair_softc *sc = (struct pair_softc *)ifp->if_softc; 195 struct ifreq *ifr = (struct ifreq *)data; 196 struct if_clone *ifc; 197 struct pair_softc *pairedsc = ifp->if_softc; 198 struct ifnet *oldifp = NULL, *newifp = NULL; 199 int error = 0, unit; 200 201 switch (cmd) { 202 case SIOCSIFADDR: 203 ifp->if_flags |= IFF_UP; 204 /* FALLTHROUGH */ 205 206 case SIOCSIFFLAGS: 207 if (ifp->if_flags & IFF_UP) 208 ifp->if_flags |= IFF_RUNNING; 209 else 210 ifp->if_flags &= ~IFF_RUNNING; 211 break; 212 213 case SIOCADDMULTI: 214 case SIOCDELMULTI: 215 break; 216 217 case SIOCGIFMEDIA: 218 case SIOCSIFMEDIA: 219 error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd); 220 break; 221 222 case SIOCSIFPAIR: 223 if (sc->sc_pairedif == ifr->ifr_index) 224 break; 225 226 /* Cannot link to myself */ 227 if (ifr->ifr_index == ifp->if_index) { 228 error = EINVAL; 229 break; 230 } 231 232 oldifp = if_get(sc->sc_pairedif); 233 newifp = if_get(ifr->ifr_index); 234 235 if (newifp != NULL) { 236 pairedsc = newifp->if_softc; 237 238 if (pairedsc->sc_pairedif != 0) { 239 error = EBUSY; 240 break; 241 } 242 243 /* Only allow pair(4) interfaces for the pair */ 244 if ((ifc = if_clone_lookup(newifp->if_xname, 245 &unit)) == NULL || strcmp("pair", 246 ifc->ifc_name) != 0) { 247 error = ENODEV; 248 break; 249 } 250 251 pairedsc->sc_pairedif = ifp->if_index; 252 sc->sc_pairedif = ifr->ifr_index; 253 } else 254 sc->sc_pairedif = 0; 255 256 if (oldifp != NULL) { 257 pairedsc = oldifp->if_softc; 258 pairedsc->sc_pairedif = 0; 259 } 260 break; 261 262 case SIOCGIFPAIR: 263 ifr->ifr_index = sc->sc_pairedif; 264 break; 265 266 default: 267 error = ether_ioctl(ifp, &sc->sc_ac, cmd, data); 268 } 269 270 if (newifp != NULL || oldifp != NULL) 271 pair_link_state(ifp); 272 if (oldifp != NULL) { 273 pair_link_state(oldifp); 274 if_put(oldifp); 275 } 276 if (newifp != NULL) { 277 pair_link_state(newifp); 278 if_put(newifp); 279 } 280 281 return (error); 282 } 283