if_virt.c revision 1.49
1 /* $NetBSD: if_virt.c,v 1.49 2014/11/06 23:25:16 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 1.49 2014/11/06 23:25:16 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; 112 113 if_initname(ifp, VIF_NAME, num); 114 ifp->if_softc = sc; 115 116 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 117 ifp->if_init = virtif_init; 118 ifp->if_ioctl = virtif_ioctl; 119 ifp->if_start = virtif_start; 120 ifp->if_stop = virtif_stop; 121 ifp->if_mtu = ETHERMTU; 122 ifp->if_dlt = DLT_EN10MB; 123 124 if_attach(ifp); 125 126 #ifndef RUMP_VIF_LINKSTR 127 /* 128 * if the underlying interface does not expect linkstr, we can 129 * create everything now. Otherwise, we need to wait for 130 * SIOCSLINKSTR. 131 */ 132 #define LINKSTRNUMLEN 16 133 sc->sc_linkstr = kmem_alloc(LINKSTRNUMLEN, KM_SLEEP); 134 snprintf(sc->sc_linkstr, LINKSTRNUMLEN, "%d", sc->sc_num); 135 #undef LINKSTRNUMLEN 136 error = virtif_create(ifp); 137 if (error) { 138 if_detach(ifp); 139 kmem_free(sc, sizeof(*sc)); 140 ifp->if_softc = NULL; 141 } 142 #endif /* !RUMP_VIF_LINKSTR */ 143 144 return error; 145 } 146 147 static int 148 virtif_unclone(struct ifnet *ifp) 149 { 150 struct virtif_sc *sc = ifp->if_softc; 151 int rv; 152 153 if (ifp->if_flags & IFF_UP) 154 return EBUSY; 155 156 if ((rv = VIFHYPER_DYING(sc->sc_viu)) != 0) 157 return rv; 158 159 virtif_stop(ifp, 1); 160 if_down(ifp); 161 162 VIFHYPER_DESTROY(sc->sc_viu); 163 164 kmem_free(sc, sizeof(*sc)); 165 166 ether_ifdetach(ifp); 167 if_detach(ifp); 168 169 return 0; 170 } 171 172 static int 173 virtif_init(struct ifnet *ifp) 174 { 175 struct virtif_sc *sc = ifp->if_softc; 176 177 if (sc->sc_viu == NULL) 178 return ENXIO; 179 180 ifp->if_flags |= IFF_RUNNING; 181 return 0; 182 } 183 184 static int 185 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 186 { 187 struct virtif_sc *sc = ifp->if_softc; 188 int rv; 189 190 switch (cmd) { 191 #ifdef RUMP_VIF_LINKSTR 192 struct ifdrv *ifd; 193 size_t linkstrlen; 194 195 #ifndef RUMP_VIF_LINKSTRMAX 196 #define RUMP_VIF_LINKSTRMAX 4096 197 #endif 198 199 case SIOCGLINKSTR: 200 ifd = data; 201 202 if (!sc->sc_linkstr) { 203 rv = ENOENT; 204 break; 205 } 206 linkstrlen = strlen(sc->sc_linkstr)+1; 207 208 if (ifd->ifd_cmd == IFLINKSTR_QUERYLEN) { 209 ifd->ifd_len = linkstrlen; 210 rv = 0; 211 break; 212 } 213 if (ifd->ifd_cmd != 0) { 214 rv = ENOTTY; 215 break; 216 } 217 218 rv = copyoutstr(sc->sc_linkstr, 219 ifd->ifd_data, MIN(ifd->ifd_len,linkstrlen), NULL); 220 break; 221 case SIOCSLINKSTR: 222 if (ifp->if_flags & IFF_UP) { 223 rv = EBUSY; 224 break; 225 } 226 227 ifd = data; 228 229 if (ifd->ifd_cmd == IFLINKSTR_UNSET) { 230 panic("unset linkstr not implemented"); 231 } else if (ifd->ifd_cmd != 0) { 232 rv = ENOTTY; 233 break; 234 } else if (sc->sc_linkstr) { 235 rv = EBUSY; 236 break; 237 } 238 239 if (ifd->ifd_len > RUMP_VIF_LINKSTRMAX) { 240 rv = E2BIG; 241 break; 242 } else if (ifd->ifd_len < 1) { 243 rv = EINVAL; 244 break; 245 } 246 247 248 sc->sc_linkstr = kmem_alloc(ifd->ifd_len, KM_SLEEP); 249 rv = copyinstr(ifd->ifd_data, sc->sc_linkstr, 250 ifd->ifd_len, NULL); 251 if (rv) { 252 kmem_free(sc->sc_linkstr, ifd->ifd_len); 253 break; 254 } 255 256 rv = virtif_create(ifp); 257 if (rv) { 258 kmem_free(sc->sc_linkstr, ifd->ifd_len); 259 } 260 break; 261 #endif /* RUMP_VIF_LINKSTR */ 262 default: 263 if (!sc->sc_linkstr) 264 rv = ENXIO; 265 else 266 rv = ether_ioctl(ifp, cmd, data); 267 if (rv == ENETRESET) 268 rv = 0; 269 break; 270 } 271 272 return rv; 273 } 274 275 /* 276 * Output packets in-context until outgoing queue is empty. 277 * Leave responsibility of choosing whether or not to drop the 278 * kernel lock to VIPHYPER_SEND(). 279 */ 280 #define LB_SH 32 281 static void 282 virtif_start(struct ifnet *ifp) 283 { 284 struct virtif_sc *sc = ifp->if_softc; 285 struct mbuf *m, *m0; 286 struct iovec io[LB_SH]; 287 int i; 288 289 ifp->if_flags |= IFF_OACTIVE; 290 291 for (;;) { 292 IF_DEQUEUE(&ifp->if_snd, m0); 293 if (!m0) { 294 break; 295 } 296 297 m = m0; 298 for (i = 0; i < LB_SH && m; ) { 299 if (m->m_len) { 300 io[i].iov_base = mtod(m, void *); 301 io[i].iov_len = m->m_len; 302 i++; 303 } 304 m = m->m_next; 305 } 306 if (i == LB_SH && m) 307 panic("lazy bum"); 308 bpf_mtap(ifp, m0); 309 310 VIFHYPER_SEND(sc->sc_viu, io, i); 311 312 m_freem(m0); 313 ifp->if_opackets++; 314 } 315 316 ifp->if_flags &= ~IFF_OACTIVE; 317 } 318 319 static void 320 virtif_stop(struct ifnet *ifp, int disable) 321 { 322 323 /* XXX: VIFHYPER_STOP() */ 324 325 ifp->if_flags &= ~IFF_RUNNING; 326 } 327 328 void 329 VIF_DELIVERPKT(struct virtif_sc *sc, struct iovec *iov, size_t iovlen) 330 { 331 struct ifnet *ifp = &sc->sc_ec.ec_if; 332 struct ether_header *eth; 333 struct mbuf *m; 334 size_t i; 335 int off, olen; 336 bool passup; 337 const int align 338 = ALIGN(sizeof(struct ether_header)) - sizeof(struct ether_header); 339 340 if ((ifp->if_flags & IFF_RUNNING) == 0) 341 return; 342 343 m = m_gethdr(M_NOWAIT, MT_DATA); 344 if (m == NULL) 345 return; /* drop packet */ 346 m->m_len = m->m_pkthdr.len = 0; 347 348 for (i = 0, off = align; i < iovlen; i++) { 349 olen = m->m_pkthdr.len; 350 m_copyback(m, off, iov[i].iov_len, iov[i].iov_base); 351 off += iov[i].iov_len; 352 if (olen + off != m->m_pkthdr.len) { 353 aprint_verbose_ifnet(ifp, "m_copyback failed\n"); 354 m_freem(m); 355 return; 356 } 357 } 358 m->m_data += align; 359 m->m_pkthdr.len -= align; 360 m->m_len -= align; 361 362 eth = mtod(m, struct ether_header *); 363 if (memcmp(eth->ether_dhost, CLLADDR(ifp->if_sadl), 364 ETHER_ADDR_LEN) == 0) { 365 passup = true; 366 } else if (ETHER_IS_MULTICAST(eth->ether_dhost)) { 367 passup = true; 368 } else if (ifp->if_flags & IFF_PROMISC) { 369 m->m_flags |= M_PROMISC; 370 passup = true; 371 } else { 372 passup = false; 373 } 374 375 if (passup) { 376 ifp->if_ipackets++; 377 m->m_pkthdr.rcvif = ifp; 378 KERNEL_LOCK(1, NULL); 379 bpf_mtap(ifp, m); 380 ifp->if_input(ifp, m); 381 KERNEL_UNLOCK_LAST(NULL); 382 } else { 383 m_freem(m); 384 } 385 m = NULL; 386 } 387 388 /* 389 * The following ensures that no two modules using if_virt end up with 390 * the same module name. MODULE() and modcmd wrapped in ... bad mojo. 391 */ 392 #define VIF_MOJO(x) MODULE(MODULE_CLASS_DRIVER,x,NULL); 393 #define VIF_MODULE() VIF_MOJO(VIF_BASENAME(if_virt_,VIRTIF_BASE)) 394 #define VIF_MODCMD VIF_BASENAME3(if_virt_,VIRTIF_BASE,_modcmd) 395 VIF_MODULE(); 396 static int 397 VIF_MODCMD(modcmd_t cmd, void *opaque) 398 { 399 int error = 0; 400 401 switch (cmd) { 402 case MODULE_CMD_INIT: 403 if_clone_attach(&VIF_CLONER); 404 break; 405 case MODULE_CMD_FINI: 406 /* 407 * not sure if interfaces are refcounted 408 * and properly protected 409 */ 410 #if 0 411 if_clone_detach(&VIF_CLONER); 412 #else 413 error = ENOTTY; 414 #endif 415 break; 416 default: 417 error = ENOTTY; 418 } 419 return error; 420 } 421
Indexes created Thu Sep 25 08:09:54 GMT 2025