1 /* $NetBSD: if_virt.c,v 1.14 2009/10/14 18:18:53 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 1.14 2009/10/14 18:18:53 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/if.h> 42 #include <net/if_ether.h> 43 #include <net/if_tap.h> 44 45 #include <netinet/in.h> 46 #include <netinet/in_var.h> 47 48 #include <rump/rump.h> 49 #include <rump/rumpuser.h> 50 51 #include "rump_private.h" 52 #include "rump_net_private.h" 53 54 /* 55 * Virtual interface for userspace purposes. Uses tap(4) to 56 * interface with the kernel and just simply shovels data 57 * to/from /dev/tap. 58 */ 59 60 #define VIRTIF_BASE "virt" 61 62 static int virtif_init(struct ifnet *); 63 static int virtif_ioctl(struct ifnet *, u_long, void *); 64 static void virtif_start(struct ifnet *); 65 static void virtif_stop(struct ifnet *, int); 66 67 struct virtif_sc { 68 struct ethercom sc_ec; 69 int sc_tapfd; 70 kmutex_t sc_sendmtx; 71 kcondvar_t sc_sendcv; 72 }; 73 74 static void virtif_worker(void *); 75 static void virtif_sender(void *); 76 77 #if 0 78 /* 79 * Create a socket and call ifioctl() to configure the interface. 80 * This trickles down to virtif_ioctl(). 81 */ 82 static int 83 configaddr(struct ifnet *ifp, struct ifaliasreq *ia) 84 { 85 struct socket *so; 86 int error; 87 88 strcpy(ia->ifra_name, ifp->if_xname); 89 error = socreate(ia->ifra_addr.sa_family, &so, SOCK_DGRAM, 90 0, curlwp, NULL); 91 if (error) 92 return error; 93 error = ifioctl(so, SIOCAIFADDR, ia, curlwp); 94 soclose(so); 95 96 return error; 97 } 98 #endif 99 100 int 101 rump_virtif_create(int num) 102 { 103 struct virtif_sc *sc; 104 struct ifnet *ifp; 105 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 106 char tapdev[16]; 107 int fd, error; 108 109 snprintf(tapdev, sizeof(tapdev), "/dev/tap%d", num); 110 fd = rumpuser_open(tapdev, O_RDWR, &error); 111 if (fd == -1) { 112 printf("virtif_create: can't open /dev/tap %d\n", error); 113 return error; 114 } 115 KASSERT(num < 0x100); 116 enaddr[2] = arc4random() & 0xff; 117 enaddr[5] = num; 118 119 sc = kmem_zalloc(sizeof(*sc), KM_SLEEP); 120 sc->sc_tapfd = fd; 121 122 ifp = &sc->sc_ec.ec_if; 123 sprintf(ifp->if_xname, "%s%d", VIRTIF_BASE, num); 124 ifp->if_softc = sc; 125 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 126 ifp->if_init = virtif_init; 127 ifp->if_ioctl = virtif_ioctl; 128 ifp->if_start = virtif_start; 129 ifp->if_stop = virtif_stop; 130 131 mutex_init(&sc->sc_sendmtx, MUTEX_DEFAULT, IPL_NONE); 132 cv_init(&sc->sc_sendcv, "virtsnd"); 133 134 if_attach(ifp); 135 ether_ifattach(ifp, enaddr); 136 137 return 0; 138 } 139 140 static int 141 virtif_init(struct ifnet *ifp) 142 { 143 int rv; 144 145 if (rump_threads) { 146 rv = kthread_create(PRI_NONE, 0, NULL, virtif_worker, ifp, 147 NULL, "virtifi"); 148 /* XXX: should do proper cleanup */ 149 if (rv) { 150 panic("if_virt: can't create worker"); 151 } 152 rv = kthread_create(PRI_NONE, 0, NULL, virtif_sender, ifp, 153 NULL, "virtifs"); 154 if (rv) { 155 panic("if_virt: can't create sender"); 156 } 157 } else { 158 printf("WARNING: threads not enabled, receive NOT working\n"); 159 } 160 ifp->if_flags |= IFF_RUNNING; 161 162 return 0; 163 } 164 165 static int 166 virtif_ioctl(struct ifnet *ifp, u_long cmd, void *data) 167 { 168 int s, rv; 169 170 s = splnet(); 171 rv = ether_ioctl(ifp, cmd, data); 172 if (rv == ENETRESET) 173 rv = 0; 174 splx(s); 175 176 return rv; 177 } 178 179 /* just send everything in-context */ 180 static void 181 virtif_start(struct ifnet *ifp) 182 { 183 struct virtif_sc *sc = ifp->if_softc; 184 185 mutex_enter(&sc->sc_sendmtx); 186 cv_signal(&sc->sc_sendcv); 187 mutex_exit(&sc->sc_sendmtx); 188 } 189 190 static void 191 virtif_stop(struct ifnet *ifp, int disable) 192 { 193 194 panic("%s: unimpl", __func__); 195 } 196 197 static void 198 virtif_worker(void *arg) 199 { 200 struct ifnet *ifp = arg; 201 struct virtif_sc *sc = ifp->if_softc; 202 struct mbuf *m; 203 size_t plen = ETHER_MAX_LEN_JUMBO+1; 204 ssize_t n; 205 int error; 206 207 for (;;) { 208 m = m_gethdr(M_WAIT, MT_DATA); 209 MEXTMALLOC(m, plen, M_WAIT); 210 211 again: 212 n = rumpuser_read(sc->sc_tapfd, mtod(m, void *), plen, &error); 213 KASSERT(n < ETHER_MAX_LEN_JUMBO); 214 if (n <= 0) { 215 /* 216 * work around tap bug: /dev/tap is opened in 217 * non-blocking mode if it previously was 218 * non-blocking. 219 */ 220 if (n == -1 && error == EAGAIN) { 221 struct pollfd pfd; 222 223 pfd.fd = sc->sc_tapfd; 224 pfd.events = POLLIN; 225 226 rumpuser_poll(&pfd, 1, INFTIM, &error); 227 goto again; 228 } 229 m_freem(m); 230 break; 231 } 232 m->m_len = m->m_pkthdr.len = n; 233 m->m_pkthdr.rcvif = ifp; 234 ether_input(ifp, m); 235 } 236 237 panic("virtif_workin is a lazy boy %d\n", error); 238 } 239 240 /* lazy bum stetson-harrison magic value */ 241 #define LB_SH 32 242 static void 243 virtif_sender(void *arg) 244 { 245 struct ifnet *ifp = arg; 246 struct virtif_sc *sc = ifp->if_softc; 247 struct mbuf *m, *m0; 248 struct rumpuser_iovec io[LB_SH]; 249 int i, error; 250 251 mutex_enter(&sc->sc_sendmtx); 252 for (;;) { 253 IF_DEQUEUE(&ifp->if_snd, m0); 254 if (!m0) { 255 cv_wait(&sc->sc_sendcv, &sc->sc_sendmtx); 256 continue; 257 } 258 mutex_exit(&sc->sc_sendmtx); 259 260 m = m0; 261 for (i = 0; i < LB_SH && m; i++) { 262 io[i].iov_base = mtod(m, void *); 263 io[i].iov_len = m->m_len; 264 m = m->m_next; 265 } 266 if (i == LB_SH) 267 panic("lazy bum"); 268 rumpuser_writev(sc->sc_tapfd, io, i, &error); 269 m_freem(m0); 270 mutex_enter(&sc->sc_sendmtx); 271 } 272 273 mutex_exit(softnet_lock); 274 } 275 276 /* 277 * dummyif is a nada-interface. 278 * As it requires nothing external, it can be used for testing 279 * interface configuration. 280 */ 281 static int dummyif_init(struct ifnet *); 282 static void dummyif_start(struct ifnet *); 283 284 void 285 rump_dummyif_create() 286 { 287 struct ifnet *ifp; 288 struct ethercom *ec; 289 uint8_t enaddr[ETHER_ADDR_LEN] = { 0xb2, 0x0a, 0x00, 0x0b, 0x0e, 0x01 }; 290 291 enaddr[2] = arc4random() & 0xff; 292 enaddr[5] = arc4random() & 0xff; 293 294 ec = kmem_zalloc(sizeof(*ec), KM_SLEEP); 295 296 ifp = &ec->ec_if; 297 strlcpy(ifp->if_xname, "dummy0", sizeof(ifp->if_xname)); 298 ifp->if_softc = ifp; 299 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 300 ifp->if_init = dummyif_init; 301 ifp->if_ioctl = virtif_ioctl; 302 ifp->if_start = dummyif_start; 303 304 if_attach(ifp); 305 ether_ifattach(ifp, enaddr); 306 } 307 308 static int 309 dummyif_init(struct ifnet *ifp) 310 { 311 312 ifp->if_flags |= IFF_RUNNING; 313 return 0; 314 } 315 316 static void 317 dummyif_start(struct ifnet *ifp) 318 { 319 320 } 321