1 /* $NetBSD: if_virt.c,v 1.19 2010/08/10 18:06:10 pooka Exp $ */ 2 3 /* 4 * Copyright (c) 2008 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 1.19 2010/08/10 18:06:10 pooka Exp $"); 30 31 #include <sys/param.h> 32 #include <sys/condvar.h> 33 #include <sys/fcntl.h> 34 #include <sys/kmem.h> 35 #include <sys/kthread.h> 36 #include <sys/mutex.h> 37 #include <sys/poll.h> 38 #include <sys/sockio.h> 39 #include <sys/socketvar.h> 40 41 #include <net/bpf.h> 42 #include <net/if.h> 43 #include <net/if_ether.h> 44 #include <net/if_tap.h> 45 46 #include <netinet/in.h> 47 #include <netinet/in_var.h> 48 49 #include <rump/rump.h> 50 #include <rump/rumpuser.h> 51 52 #include "rump_private.h" 53 #include "rump_net_private.h" 54 55 /* 56 * Virtual interface for userspace purposes. Uses tap(4) to 57 * interface with the kernel and just simply shovels data 58 * to/from /dev/tap. 59 */ 60 61 #define VIRTIF_BASE "virt" 62 63 static int virtif_init(struct ifnet *); 64 static int virtif_ioctl(struct ifnet *, u_long, void *); 65 static void virtif_start(struct ifnet *); 66 static void virtif_stop(struct ifnet *, int); 67 68 struct virtif_sc { 69 struct ethercom sc_ec; 70 int sc_tapfd; 71 kmutex_t sc_sendmtx; 72 kcondvar_t sc_sendcv; 73 }; 74 75 static void virtif_worker(void *); 76 static void virtif_sender(void *); 77 78 #if 0 79 /* 80 * Create a socket and call ifioctl() to configure the interface. 81 * This trickles down to virtif_ioctl(). 82 */ 83 static int 84 configaddr(struct ifnet *ifp, struct ifaliasreq *ia) 85 { 86 struct socket *so; 87 int error; 88 89 strcpy(ia->ifra_name, ifp->if_xname); 90 error = socreate(ia->ifra_addr.sa_family, &so, SOCK_DGRAM, 91 0, curlwp, NULL); 92 if (error) 93 return error; 94 error = ifioctl(so, SIOCAIFADDR, ia, curlwp); 95 soclose(so); 96 97 return error; 98 } 99 #endif 100 101 int 102 rump_virtif_create(int num) 103 { 104 struct virtif_sc *sc; 105 struct ifnet *ifp; 106 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 107 char tapdev[16]; 108 int fd, error; 109 110 snprintf(tapdev, sizeof(tapdev), "/dev/tap%d", num); 111 fd = rumpuser_open(tapdev, O_RDWR, &error); 112 if (fd == -1) { 113 printf("virtif_create: can't open /dev/tap%d: %d\n", 114 num, error); 115 return error; 116 } 117 KASSERT(num < 0x100); 118 enaddr[2] = arc4random() & 0xff; 119 enaddr[5] = num; 120 121 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 122 sc->sc_tapfd = fd; 123 124 ifp = &sc->sc_ec.ec_if; 125 sprintf(ifp->if_xname, "%s%d", VIRTIF_BASE, num); 126 ifp->if_softc = sc; 127 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 128 ifp->if_init = virtif_init; 129 ifp->if_ioctl = virtif_ioctl; 130 ifp->if_start = virtif_start; 131 ifp->if_stop = virtif_stop; 132 133 mutex_init(&sc->sc_sendmtx, MUTEX_DEFAULT, IPL_NONE); 134 cv_init(&sc->sc_sendcv, "virtsnd"); 135 136 if_attach(ifp); 137 ether_ifattach(ifp, enaddr); 138 139 return 0; 140 } 141 142 static int 143 virtif_init(struct ifnet *ifp) 144 { 145 int rv; 146 147 if (rump_threads) { 148 rv = kthread_create(PRI_NONE, 0, NULL, virtif_worker, ifp, 149 NULL, "virtifi"); 150 /* XXX: should do proper cleanup */ 151 if (rv) { 152 panic("if_virt: can't create worker"); 153 } 154 rv = kthread_create(PRI_NONE, 0, NULL, virtif_sender, ifp, 155 NULL, "virtifs"); 156 if (rv) { 157 panic("if_virt: can't create sender"); 158 } 159 } else { 160 printf("WARNING: threads not enabled, receive NOT working\n"); 161 } 162 ifp->if_flags |= IFF_RUNNING; 163 164 return 0; 165 } 166 167 static int 168 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 169 { 170 int s, rv; 171 172 s = splnet(); 173 rv = ether_ioctl(ifp, cmd, data); 174 if (rv == ENETRESET) 175 rv = 0; 176 splx(s); 177 178 return rv; 179 } 180 181 /* just send everything in-context */ 182 static void 183 virtif_start(struct ifnet *ifp) 184 { 185 struct virtif_sc *sc = ifp->if_softc; 186 187 mutex_enter(&sc->sc_sendmtx); 188 cv_signal(&sc->sc_sendcv); 189 mutex_exit(&sc->sc_sendmtx); 190 } 191 192 static void 193 virtif_stop(struct ifnet *ifp, int disable) 194 { 195 196 panic("%s: unimpl", __func__); 197 } 198 199 static void 200 virtif_worker(void *arg) 201 { 202 struct ifnet *ifp = arg; 203 struct virtif_sc *sc = ifp->if_softc; 204 struct mbuf *m; 205 size_t plen = ETHER_MAX_LEN_JUMBO+1; 206 ssize_t n; 207 int error; 208 209 for (;;) { 210 m = m_gethdr(M_WAIT, MT_DATA); 211 MEXTMALLOC(m, plen, M_WAIT); 212 213 again: 214 n = rumpuser_read(sc->sc_tapfd, mtod(m, void *), plen, &error); 215 KASSERT(n < ETHER_MAX_LEN_JUMBO); 216 if (__predict_false(n < 0)) { 217 /* 218 * work around tap bug: /dev/tap is opened in 219 * non-blocking mode if it previously was 220 * non-blocking. 221 */ 222 if (n == -1 && error == EAGAIN) { 223 struct pollfd pfd; 224 225 pfd.fd = sc->sc_tapfd; 226 pfd.events = POLLIN; 227 228 rumpuser_poll(&pfd, 1, INFTIM, &error); 229 goto again; 230 } 231 232 m_freem(m); 233 break; 234 } 235 236 /* tap sometimes returns EOF. don't sweat it and plow on */ 237 if (__predict_false(n == 0)) 238 goto again; 239 240 m->m_len = m->m_pkthdr.len = n; 241 m->m_pkthdr.rcvif = ifp; 242 bpf_mtap(ifp, m); 243 ether_input(ifp, m); 244 } 245 246 panic("virtif_workin is a lazy boy %d\n", error); 247 } 248 249 /* lazy bum stetson-harrison magic value */ 250 #define LB_SH 32 251 static void 252 virtif_sender(void *arg) 253 { 254 struct ifnet *ifp = arg; 255 struct virtif_sc *sc = ifp->if_softc; 256 struct mbuf *m, *m0; 257 struct rumpuser_iovec io[LB_SH]; 258 int i, error; 259 260 mutex_enter(&sc->sc_sendmtx); 261 for (;;) { 262 IF_DEQUEUE(&ifp->if_snd, m0); 263 if (!m0) { 264 cv_wait(&sc->sc_sendcv, &sc->sc_sendmtx); 265 continue; 266 } 267 mutex_exit(&sc->sc_sendmtx); 268 269 m = m0; 270 for (i = 0; i < LB_SH && m; i++) { 271 io[i].iov_base = mtod(m, void *); 272 io[i].iov_len = m->m_len; 273 m = m->m_next; 274 } 275 if (i == LB_SH) 276 panic("lazy bum"); 277 bpf_mtap(ifp, m0); 278 rumpuser_writev(sc->sc_tapfd, io, i, &error); 279 m_freem(m0); 280 mutex_enter(&sc->sc_sendmtx); 281 } 282 283 mutex_exit(softnet_lock); 284 } 285 286 /* 287 * dummyif is a nada-interface. 288 * As it requires nothing external, it can be used for testing 289 * interface configuration. 290 */ 291 static int dummyif_init(struct ifnet *); 292 static void dummyif_start(struct ifnet *); 293 294 void 295 rump_dummyif_create() 296 { 297 struct ifnet *ifp; 298 struct ethercom *ec; 299 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 300 301 enaddr[2] = arc4random() & 0xff; 302 enaddr[5] = arc4random() & 0xff; 303 304 ec = kmem_zalloc(sizeof(*ec), KM_SLEEP); 305 306 ifp = &ec->ec_if; 307 strlcpy(ifp->if_xname, "dummy0", sizeof(ifp->if_xname)); 308 ifp->if_softc = ifp; 309 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 310 ifp->if_init = dummyif_init; 311 ifp->if_ioctl = virtif_ioctl; 312 ifp->if_start = dummyif_start; 313 314 if_attach(ifp); 315 ether_ifattach(ifp, enaddr); 316 } 317 318 static int 319 dummyif_init(struct ifnet *ifp) 320 { 321 322 ifp->if_flags |= IFF_RUNNING; 323 return 0; 324 } 325 326 static void 327 dummyif_start(struct ifnet *ifp) 328 { 329 330 } 331