1 /* $OpenBSD: if_pair.c,v 1.16 2020/08/21 22:59:27 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 ifnet *); 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_start = pairstart; 120 ifp->if_xflags = IFXF_CLONED; 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 ifnet *ifp) 162 { 163 struct pair_softc *sc = (struct pair_softc *)ifp->if_softc; 164 struct mbuf_list ml = MBUF_LIST_INITIALIZER(); 165 struct ifnet *pairedifp; 166 struct mbuf *m; 167 168 pairedifp = if_get(sc->sc_pairedif); 169 170 for (;;) { 171 m = ifq_dequeue(&ifp->if_snd); 172 if (m == NULL) 173 break; 174 175 #if NBPFILTER > 0 176 if (ifp->if_bpf) 177 bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_OUT); 178 #endif /* NBPFILTER > 0 */ 179 180 if (pairedifp != NULL) { 181 if (m->m_flags & M_PKTHDR) 182 m_resethdr(m); 183 ml_enqueue(&ml, m); 184 } else 185 m_freem(m); 186 } 187 188 if (pairedifp != NULL) { 189 if_input(pairedifp, &ml); 190 if_put(pairedifp); 191 } 192 } 193 194 int 195 pairioctl(struct ifnet *ifp, u_long cmd, caddr_t data) 196 { 197 struct pair_softc *sc = (struct pair_softc *)ifp->if_softc; 198 struct ifreq *ifr = (struct ifreq *)data; 199 struct if_clone *ifc; 200 struct pair_softc *pairedsc = ifp->if_softc; 201 struct ifnet *oldifp = NULL, *newifp = NULL; 202 int error = 0, unit; 203 204 switch (cmd) { 205 case SIOCSIFADDR: 206 ifp->if_flags |= IFF_UP; 207 /* FALLTHROUGH */ 208 209 case SIOCSIFFLAGS: 210 if (ifp->if_flags & IFF_UP) 211 ifp->if_flags |= IFF_RUNNING; 212 else 213 ifp->if_flags &= ~IFF_RUNNING; 214 break; 215 216 case SIOCADDMULTI: 217 case SIOCDELMULTI: 218 break; 219 220 case SIOCGIFMEDIA: 221 case SIOCSIFMEDIA: 222 error = ifmedia_ioctl(ifp, ifr, &sc->sc_media, cmd); 223 break; 224 225 case SIOCSIFPAIR: 226 if (sc->sc_pairedif == ifr->ifr_index) 227 break; 228 229 /* Cannot link to myself */ 230 if (ifr->ifr_index == ifp->if_index) { 231 error = EINVAL; 232 break; 233 } 234 235 oldifp = if_get(sc->sc_pairedif); 236 newifp = if_get(ifr->ifr_index); 237 238 if (newifp != NULL) { 239 pairedsc = newifp->if_softc; 240 241 if (pairedsc->sc_pairedif != 0) { 242 error = EBUSY; 243 break; 244 } 245 246 /* Only allow pair(4) interfaces for the pair */ 247 if ((ifc = if_clone_lookup(newifp->if_xname, 248 &unit)) == NULL || strcmp("pair", 249 ifc->ifc_name) != 0) { 250 error = ENODEV; 251 break; 252 } 253 254 pairedsc->sc_pairedif = ifp->if_index; 255 sc->sc_pairedif = ifr->ifr_index; 256 } else 257 sc->sc_pairedif = 0; 258 259 if (oldifp != NULL) { 260 pairedsc = oldifp->if_softc; 261 pairedsc->sc_pairedif = 0; 262 } 263 break; 264 265 case SIOCGIFPAIR: 266 ifr->ifr_index = sc->sc_pairedif; 267 break; 268 269 default: 270 error = ether_ioctl(ifp, &sc->sc_ac, cmd, data); 271 } 272 273 if (newifp != NULL || oldifp != NULL) 274 pair_link_state(ifp); 275 if (oldifp != NULL) { 276 pair_link_state(oldifp); 277 if_put(oldifp); 278 } 279 if (newifp != NULL) { 280 pair_link_state(newifp); 281 if_put(newifp); 282 } 283 284 return (error); 285 } 286