if_virt.c revision 1.44
1 /* $NetBSD: if_virt.c,v 1.44 2014/03/13 21:11:12 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2008, 2013 Antti Kantee. All Rights Reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __KERNEL_RCSID(0, "$NetBSD: if_virt.c,v 1.44 2014/03/13 21:11:12 pooka Exp $"); 30 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/kmem.h> 34 #include <sys/cprng.h> 35 #include <sys/module.h> 36 37 #include <net/bpf.h> 38 #include <net/if.h> 39 #include <net/if_dl.h> 40 #include <net/if_ether.h> 41 42 #include <netinet/in.h> 43 #include <netinet/in_var.h> 44 45 #include "if_virt.h" 46 #include "virtif_user.h" 47 48 /* 49 * Virtual interface. Uses hypercalls to shovel packets back 50 * and forth. The exact method for shoveling depends on the 51 * hypercall implementation. 52 */ 53 54 static int virtif_init(struct ifnet *); 55 static int virtif_ioctl(struct ifnet *, u_long, void *); 56 static void virtif_start(struct ifnet *); 57 static void virtif_stop(struct ifnet *, int); 58 59 struct virtif_sc { 60 struct ethercom sc_ec; 61 struct virtif_user *sc_viu; 62 63 int sc_num; 64 char *sc_linkstr; 65 }; 66 67 static int virtif_clone(struct if_clone *, int); 68 static int virtif_unclone(struct ifnet *); 69 70 struct if_clone VIF_CLONER = 71 IF_CLONE_INITIALIZER(VIF_NAME, virtif_clone, virtif_unclone); 72 73 static int 74 virtif_create(struct ifnet *ifp) 75 { 76 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 77 char enaddrstr[3*ETHER_ADDR_LEN]; 78 struct virtif_sc *sc = ifp->if_softc; 79 int error; 80 81 if (sc->sc_viu) 82 panic("%s: already created", ifp->if_xname); 83 84 enaddr[2] = cprng_fast32() & 0xff; 85 enaddr[5] = sc->sc_num & 0xff; 86 87 if ((error = VIFHYPER_CREATE(sc->sc_linkstr, 88 sc, enaddr, &sc->sc_viu)) != 0) { 89 printf("VIFHYPER_CREATE failed: %d\n", error); 90 return error; 91 } 92 93 ether_ifattach(ifp, enaddr); 94 ether_snprintf(enaddrstr, sizeof(enaddrstr), enaddr); 95 aprint_normal_ifnet(ifp, "Ethernet address %s\n", enaddrstr); 96 97 IFQ_SET_READY(&ifp->if_snd); 98 99 return 0; 100 } 101 102 static int 103 virtif_clone(struct if_clone *ifc, int num) 104 { 105 struct virtif_sc *sc; 106 struct ifnet *ifp; 107 int error = 0; 108 109 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 110 sc->sc_num = num; 111 ifp = &sc->sc_ec.ec_if; 112 sprintf(ifp->if_xname, "%s%d", VIF_NAME, num); 113 ifp->if_softc = sc; 114 115 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 116 ifp->if_init = virtif_init; 117 ifp->if_ioctl = virtif_ioctl; 118 ifp->if_start = virtif_start; 119 ifp->if_stop = virtif_stop; 120 ifp->if_mtu = ETHERMTU; 121 ifp->if_dlt = DLT_EN10MB; 122 123 if_attach(ifp); 124 125 #ifndef RUMP_VIF_LINKSTR 126 /* 127 * if the underlying interface does not expect linkstr, we can 128 * create everything now. Otherwise, we need to wait for 129 * SIOCSLINKSTR. 130 */ 131 #define LINKSTRNUMLEN 16 132 sc->sc_linkstr = kmem_alloc(LINKSTRNUMLEN, KM_SLEEP); 133 snprintf(sc->sc_linkstr, LINKSTRNUMLEN, "%d", sc->sc_num); 134 #undef LINKSTRNUMLEN 135 error = virtif_create(ifp); 136 if (error) { 137 if_detach(ifp); 138 kmem_free(sc, sizeof(*sc)); 139 ifp->if_softc = NULL; 140 } 141 #endif /* !RUMP_VIF_LINKSTR */ 142 143 return error; 144 } 145 146 static int 147 virtif_unclone(struct ifnet *ifp) 148 { 149 struct virtif_sc *sc = ifp->if_softc; 150 int rv; 151 152 if (ifp->if_flags & IFF_UP) 153 return EBUSY; 154 155 if ((rv = VIFHYPER_DYING(sc->sc_viu)) != 0) 156 return rv; 157 158 virtif_stop(ifp, 1); 159 if_down(ifp); 160 161 VIFHYPER_DESTROY(sc->sc_viu); 162 163 kmem_free(sc, sizeof(*sc)); 164 165 ether_ifdetach(ifp); 166 if_detach(ifp); 167 168 return 0; 169 } 170 171 static int 172 virtif_init(struct ifnet *ifp) 173 { 174 struct virtif_sc *sc = ifp->if_softc; 175 176 if (sc->sc_viu == NULL) 177 return ENXIO; 178 179 ifp->if_flags |= IFF_RUNNING; 180 return 0; 181 } 182 183 static int 184 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 185 { 186 struct virtif_sc *sc = ifp->if_softc; 187 int rv; 188 189 switch (cmd) { 190 #ifdef RUMP_VIF_LINKSTR 191 struct ifdrv *ifd; 192 size_t linkstrlen; 193 194 #ifndef RUMP_VIF_LINKSTRMAX 195 #define RUMP_VIF_LINKSTRMAX 4096 196 #endif 197 198 case SIOCGLINKSTR: 199 ifd = data; 200 201 if (!sc->sc_linkstr) { 202 rv = ENOENT; 203 break; 204 } 205 linkstrlen = strlen(sc->sc_linkstr)+1; 206 207 if (ifd->ifd_cmd == IFLINKSTR_QUERYLEN) { 208 ifd->ifd_len = linkstrlen; 209 rv = 0; 210 break; 211 } 212 if (ifd->ifd_cmd != 0) { 213 rv = ENOTTY; 214 break; 215 } 216 217 rv = copyoutstr(sc->sc_linkstr, 218 ifd->ifd_data, MIN(ifd->ifd_len,linkstrlen), NULL); 219 break; 220 case SIOCSLINKSTR: 221 if (ifp->if_flags & IFF_UP) { 222 rv = EBUSY; 223 break; 224 } 225 226 ifd = data; 227 228 if (ifd->ifd_cmd == IFLINKSTR_UNSET) { 229 panic("unset linkstr not implemented"); 230 } else if (ifd->ifd_cmd != 0) { 231 rv = ENOTTY; 232 break; 233 } else if (sc->sc_linkstr) { 234 rv = EBUSY; 235 break; 236 } 237 238 if (ifd->ifd_len > RUMP_VIF_LINKSTRMAX) { 239 rv = E2BIG; 240 break; 241 } else if (ifd->ifd_len < 1) { 242 rv = EINVAL; 243 break; 244 } 245 246 247 sc->sc_linkstr = kmem_alloc(ifd->ifd_len, KM_SLEEP); 248 rv = copyinstr(ifd->ifd_data, sc->sc_linkstr, 249 ifd->ifd_len, NULL); 250 if (rv) { 251 kmem_free(sc->sc_linkstr, ifd->ifd_len); 252 break; 253 } 254 255 rv = virtif_create(ifp); 256 if (rv) { 257 kmem_free(sc->sc_linkstr, ifd->ifd_len); 258 } 259 break; 260 #endif /* RUMP_VIF_LINKSTR */ 261 default: 262 if (!sc->sc_linkstr) 263 rv = ENXIO; 264 else 265 rv = ether_ioctl(ifp, cmd, data); 266 if (rv == ENETRESET) 267 rv = 0; 268 break; 269 } 270 271 return rv; 272 } 273 274 /* 275 * Output packets in-context until outgoing queue is empty. 276 * Leave responsibility of choosing whether or not to drop the 277 * kernel lock to VIPHYPER_SEND(). 278 */ 279 #define LB_SH 32 280 static void 281 virtif_start(struct ifnet *ifp) 282 { 283 struct virtif_sc *sc = ifp->if_softc; 284 struct mbuf *m, *m0; 285 struct iovec io[LB_SH]; 286 int i; 287 288 ifp->if_flags |= IFF_OACTIVE; 289 290 for (;;) { 291 IF_DEQUEUE(&ifp->if_snd, m0); 292 if (!m0) { 293 break; 294 } 295 296 m = m0; 297 for (i = 0; i < LB_SH && m; ) { 298 if (m->m_len) { 299 io[i].iov_base = mtod(m, void *); 300 io[i].iov_len = m->m_len; 301 i++; 302 } 303 m = m->m_next; 304 } 305 if (i == LB_SH && m) 306 panic("lazy bum"); 307 bpf_mtap(ifp, m0); 308 309 VIFHYPER_SEND(sc->sc_viu, io, i); 310 311 m_freem(m0); 312 } 313 314 ifp->if_flags &= ~IFF_OACTIVE; 315 } 316 317 static void 318 virtif_stop(struct ifnet *ifp, int disable) 319 { 320 321 /* XXX: VIFHYPER_STOP() */ 322 323 ifp->if_flags &= ~IFF_RUNNING; 324 } 325 326 void 327 VIF_DELIVERPKT(struct virtif_sc *sc, struct iovec *iov, size_t iovlen) 328 { 329 struct ifnet *ifp = &sc->sc_ec.ec_if; 330 struct ether_header *eth; 331 struct mbuf *m; 332 size_t i; 333 int off, olen; 334 bool passup; 335 const int align 336 = ALIGN(sizeof(struct ether_header)) - sizeof(struct ether_header); 337 338 if ((ifp->if_flags & IFF_RUNNING) == 0) 339 return; 340 341 m = m_gethdr(M_NOWAIT, MT_DATA); 342 if (m == NULL) 343 return; /* drop packet */ 344 m->m_len = m->m_pkthdr.len = 0; 345 346 for (i = 0, off = align; i < iovlen; i++) { 347 olen = m->m_pkthdr.len; 348 m_copyback(m, off, iov[i].iov_len, iov[i].iov_base); 349 off += iov[i].iov_len; 350 if (olen + off != m->m_pkthdr.len) { 351 aprint_verbose_ifnet(ifp, "m_copyback failed\n"); 352 m_freem(m); 353 return; 354 } 355 } 356 357 m->m_data += align; 358 eth = mtod(m, struct ether_header *); 359 if (memcmp(eth->ether_dhost, CLLADDR(ifp->if_sadl), 360 ETHER_ADDR_LEN) == 0) { 361 passup = true; 362 } else if (ETHER_IS_MULTICAST(eth->ether_dhost)) { 363 passup = true; 364 } else if (ifp->if_flags & IFF_PROMISC) { 365 m->m_flags |= M_PROMISC; 366 passup = true; 367 } else { 368 passup = false; 369 } 370 371 if (passup) { 372 m->m_pkthdr.rcvif = ifp; 373 KERNEL_LOCK(1, NULL); 374 bpf_mtap(ifp, m); 375 ifp->if_input(ifp, m); 376 KERNEL_UNLOCK_LAST(NULL); 377 } else { 378 m_freem(m); 379 } 380 m = NULL; 381 } 382 383 MODULE(MODULE_CLASS_DRIVER, if_virt, NULL); 384 385 static int 386 if_virt_modcmd(modcmd_t cmd, void *opaque) 387 { 388 int error = 0; 389 390 switch (cmd) { 391 case MODULE_CMD_INIT: 392 if_clone_attach(&VIF_CLONER); 393 break; 394 case MODULE_CMD_FINI: 395 /* 396 * not sure if interfaces are refcounted 397 * and properly protected 398 */ 399 #if 0 400 if_clone_detach(&VIF_CLONER); 401 #else 402 error = ENOTTY; 403 #endif 404 break; 405 default: 406 error = ENOTTY; 407 } 408 return error; 409 } 410
Indexes created Fri Sep 26 08:10:20 GMT 2025