sys/netgraph7/ng_eiface.c

   1 /*-
   2  *
   3  * Copyright (c) 1999-2001, Vitaly V Belekhov
   4  * 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 unmodified, this list of conditions, and the following
  11  *    disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD: src/sys/netgraph/ng_eiface.c,v 1.39 2007/07/26 10:54:33 glebius Exp $
  29  */
  30
  31 #include <sys/param.h>
  32 #include <sys/systm.h>
  33 #include <sys/errno.h>
  34 #include <sys/kernel.h>
  35 #include <sys/malloc.h>
  36 #include <sys/mbuf.h>
  37 #include <sys/errno.h>
  38 #include <sys/sockio.h>
  39 #include <sys/socket.h>
  40 #include <sys/syslog.h>
  41
  42 #include <net/if.h>
  43 #include <net/if_types.h>
  44 #include <net/netisr.h>
  45
  46 #include <netgraph/ng_message.h>
  47 #include <netgraph/netgraph.h>
  48 #include <netgraph/ng_parse.h>
  49 #include <netgraph/ng_eiface.h>
  50
  51 #include <net/bpf.h>
  52 #include <net/ethernet.h>
  53 #include <net/if_arp.h>
  54
  55 static const struct ng_cmdlist ng_eiface_cmdlist[] = {
  56         {
  57           NGM_EIFACE_COOKIE,
  58           NGM_EIFACE_GET_IFNAME,
  59           "getifname",
  60           NULL,
  61           &ng_parse_string_type
  62         },
  63         {
  64           NGM_EIFACE_COOKIE,
  65           NGM_EIFACE_SET,
  66           "set",
  67           &ng_parse_enaddr_type,
  68           NULL
  69         },
  70         { 0 }
  71 };
  72
  73 /* Node private data */
  74 struct ng_eiface_private {
  75         struct ifnet    *ifp;           /* per-interface network data */
  76         int             unit;           /* Interface unit number */
  77         node_p          node;           /* Our netgraph node */
  78         hook_p          ether;          /* Hook for ethernet stream */
  79 };
  80 typedef struct ng_eiface_private *priv_p;
  81
  82 /* Interface methods */
  83 static void     ng_eiface_init(void *xsc);
  84 static void     ng_eiface_start(struct ifnet *ifp);
  85 static int      ng_eiface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
  86 #ifdef DEBUG
  87 static void     ng_eiface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
  88 #endif
  89
  90 /* Netgraph methods */
  91 static int              ng_eiface_mod_event(module_t, int, void *);
  92 static ng_constructor_t ng_eiface_constructor;
  93 static ng_rcvmsg_t      ng_eiface_rcvmsg;
  94 static ng_shutdown_t    ng_eiface_rmnode;
  95 static ng_newhook_t     ng_eiface_newhook;
  96 static ng_rcvdata_t     ng_eiface_rcvdata;
  97 static ng_disconnect_t  ng_eiface_disconnect;
  98
  99 /* Node type descriptor */
 100 static struct ng_type typestruct = {
 101         .version =      NG_ABI_VERSION,
 102         .name =         NG_EIFACE_NODE_TYPE,
 103         .mod_event =    ng_eiface_mod_event,
 104         .constructor =  ng_eiface_constructor,
 105         .rcvmsg =       ng_eiface_rcvmsg,
 106         .shutdown =     ng_eiface_rmnode,
 107         .newhook =      ng_eiface_newhook,
 108         .rcvdata =      ng_eiface_rcvdata,
 109         .disconnect =   ng_eiface_disconnect,
 110         .cmdlist =      ng_eiface_cmdlist
 111 };
 112 NETGRAPH_INIT(eiface, &typestruct);
 113
 114 static struct unrhdr    *ng_eiface_unit;
 115
 116 /************************************************************************
 117                         INTERFACE STUFF
 118  ************************************************************************/
 119
 120 /*
 121  * Process an ioctl for the virtual interface
 122  */
 123 static int
 124 ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
 125 {
 126         struct ifreq *const ifr = (struct ifreq *)data;
 127         int s, error = 0;
 128
 129 #ifdef DEBUG
 130         ng_eiface_print_ioctl(ifp, command, data);
 131 #endif
 132         s = splimp();
 133         switch (command) {
 134
 135         /* These two are mostly handled at a higher layer */
 136         case SIOCSIFADDR:
 137                 error = ether_ioctl(ifp, command, data);
 138                 break;
 139         case SIOCGIFADDR:
 140                 break;
 141
 142         /* Set flags */
 143         case SIOCSIFFLAGS:
 144                 /*
 145                  * If the interface is marked up and stopped, then start it.
 146                  * If it is marked down and running, then stop it.
 147                  */
 148                 if (ifp->if_flags & IFF_UP) {
 149                         if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
 150                                 ifp->if_drv_flags &= ~(IFF_DRV_OACTIVE);
 151                                 ifp->if_drv_flags |= IFF_DRV_RUNNING;
 152                         }
 153                 } else {
 154                         if (ifp->if_drv_flags & IFF_DRV_RUNNING)
 155                                 ifp->if_drv_flags &= ~(IFF_DRV_RUNNING |
 156                                     IFF_DRV_OACTIVE);
 157                 }
 158                 break;
 159
 160         /* Set the interface MTU */
 161         case SIOCSIFMTU:
 162                 if (ifr->ifr_mtu > NG_EIFACE_MTU_MAX ||
 163                     ifr->ifr_mtu < NG_EIFACE_MTU_MIN)
 164                         error = EINVAL;
 165                 else
 166                         ifp->if_mtu = ifr->ifr_mtu;
 167                 break;
 168
 169         /* Stuff that's not supported */
 170         case SIOCADDMULTI:
 171         case SIOCDELMULTI:
 172                 error = 0;
 173                 break;
 174         case SIOCSIFPHYS:
 175                 error = EOPNOTSUPP;
 176                 break;
 177
 178         default:
 179                 error = EINVAL;
 180                 break;
 181         }
 182         splx(s);
 183         return (error);
 184 }
 185
 186 static void
 187 ng_eiface_init(void *xsc)
 188 {
 189         priv_p sc = xsc;
 190         struct ifnet *ifp = sc->ifp;
 191         int s;
 192
 193         s = splimp();
 194
 195         ifp->if_drv_flags |= IFF_DRV_RUNNING;
 196         ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
 197
 198         splx(s);
 199 }
 200
 201 /*
 202  * We simply relay the packet to the "ether" hook, if it is connected.
 203  * We have been through the netgraph locking and are guaranteed to
 204  * be the only code running in this node at this time.
 205  */
 206 static void
 207 ng_eiface_start2(node_p node, hook_p hook, void *arg1, int arg2)
 208 {
 209         struct ifnet *ifp = arg1;
 210         const priv_p priv = (priv_p)ifp->if_softc;
 211         int error = 0;
 212         struct mbuf *m;
 213
 214         /* Check interface flags */
 215
 216         if (!((ifp->if_flags & IFF_UP) &&
 217             (ifp->if_drv_flags & IFF_DRV_RUNNING)))
 218                 return;
 219
 220         for (;;) {
 221                 /*
 222                  * Grab a packet to transmit.
 223                  */
 224                 IF_DEQUEUE(&ifp->if_snd, m);
 225
 226                 /* If there's nothing to send, break. */
 227                 if (m == NULL)
 228                         break;
 229
 230                 /*
 231                  * Berkeley packet filter.
 232                  * Pass packet to bpf if there is a listener.
 233                  * XXX is this safe? locking?
 234                  */
 235                 BPF_MTAP(ifp, m);
 236
 237                 if (ifp->if_flags & IFF_MONITOR) {
 238                         ifp->if_ipackets++;
 239                         m_freem(m);
 240                         continue;
 241                 }
 242
 243                 /*
 244                  * Send packet; if hook is not connected, mbuf will get
 245                  * freed.
 246                  */
 247                 NG_SEND_DATA_ONLY(error, priv->ether, m);
 248
 249                 /* Update stats */
 250                 if (error == 0)
 251                         ifp->if_opackets++;
 252                 else
 253                         ifp->if_oerrors++;
 254         }
 255
 256         ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
 257
 258         return;
 259 }
 260
 261 /*
 262  * This routine is called to deliver a packet out the interface.
 263  * We simply queue the netgraph version to be called when netgraph locking
 264  * allows it to happen.
 265  * Until we know what the rest of the networking code is doing for
 266  * locking, we don't know how we will interact with it.
 267  * Take comfort from the fact that the ifnet struct is part of our
 268  * private info and can't go away while we are queued.
 269  * [Though we don't know it is still there now....]
 270  * it is possible we don't gain anything from this because
 271  * we would like to get the mbuf and queue it as data
 272  * somehow, but we can't and if we did would we solve anything?
 273  */
 274 static void
 275 ng_eiface_start(struct ifnet *ifp)
 276 {
 277
 278         const priv_p priv = (priv_p)ifp->if_softc;
 279
 280         /* Don't do anything if output is active */
 281         if (ifp->if_drv_flags & IFF_DRV_OACTIVE)
 282                 return;
 283
 284         ifp->if_drv_flags |= IFF_DRV_OACTIVE;
 285
 286         if (ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0) != 0)
 287                 ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
 288 }
 289
 290 #ifdef DEBUG
 291 /*
 292  * Display an ioctl to the virtual interface
 293  */
 294
 295 static void
 296 ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
 297 {
 298         char *str;
 299
 300         switch (command & IOC_DIRMASK) {
 301         case IOC_VOID:
 302                 str = "IO";
 303                 break;
 304         case IOC_OUT:
 305                 str = "IOR";
 306                 break;
 307         case IOC_IN:
 308                 str = "IOW";
 309                 break;
 310         case IOC_INOUT:
 311                 str = "IORW";
 312                 break;
 313         default:
 314                 str = "IO??";
 315         }
 316         log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
 317             ifp->if_xname,
 318             str,
 319             IOCGROUP(command),
 320             command & 0xff,
 321             IOCPARM_LEN(command));
 322 }
 323 #endif /* DEBUG */
 324
 325 /************************************************************************
 326                         NETGRAPH NODE STUFF
 327  ************************************************************************/
 328
 329 /*
 330  * Constructor for a node
 331  */
 332 static int
 333 ng_eiface_constructor(node_p node)
 334 {
 335         struct ifnet *ifp;
 336         priv_p priv;
 337         u_char eaddr[6] = {0,0,0,0,0,0};
 338
 339         /* Allocate node and interface private structures */
 340         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
 341         if (priv == NULL)
 342                 return (ENOMEM);
 343
 344         ifp = priv->ifp = if_alloc(IFT_ETHER);
 345         if (ifp == NULL) {
 346                 free(priv, M_NETGRAPH);
 347                 return (ENOSPC);
 348         }
 349
 350         /* Link them together */
 351         ifp->if_softc = priv;
 352
 353         /* Get an interface unit number */
 354         priv->unit = alloc_unr(ng_eiface_unit);
 355
 356         /* Link together node and private info */
 357         NG_NODE_SET_PRIVATE(node, priv);
 358         priv->node = node;
 359
 360         /* Initialize interface structure */
 361         if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
 362         ifp->if_init = ng_eiface_init;
 363         ifp->if_output = ether_output;
 364         ifp->if_start = ng_eiface_start;
 365         ifp->if_ioctl = ng_eiface_ioctl;
 366         ifp->if_watchdog = NULL;
 367         ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
 368         ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
 369
 370 #if 0
 371         /* Give this node name */
 372         bzero(ifname, sizeof(ifname));
 373         sprintf(ifname, "if%s", ifp->if_xname);
 374         (void)ng_name_node(node, ifname);
 375 #endif
 376
 377         /* Attach the interface */
 378         ether_ifattach(ifp, eaddr);
 379
 380         /* Done */
 381         return (0);
 382 }
 383
 384 /*
 385  * Give our ok for a hook to be added
 386  */
 387 static int
 388 ng_eiface_newhook(node_p node, hook_p hook, const char *name)
 389 {
 390         priv_p priv = NG_NODE_PRIVATE(node);
 391         struct ifnet *ifp = priv->ifp;
 392
 393         if (strcmp(name, NG_EIFACE_HOOK_ETHER))
 394                 return (EPFNOSUPPORT);
 395         if (priv->ether != NULL)
 396                 return (EISCONN);
 397         priv->ether = hook;
 398         NG_HOOK_SET_PRIVATE(hook, &priv->ether);
 399
 400         if_link_state_change(ifp, LINK_STATE_UP);
 401
 402         return (0);
 403 }
 404
 405 /*
 406  * Receive a control message
 407  */
 408 static int
 409 ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
 410 {
 411         const priv_p priv = NG_NODE_PRIVATE(node);
 412         struct ifnet *const ifp = priv->ifp;
 413         struct ng_mesg *resp = NULL;
 414         int error = 0;
 415         struct ng_mesg *msg;
 416
 417         NGI_GET_MSG(item, msg);
 418         switch (msg->header.typecookie) {
 419         case NGM_EIFACE_COOKIE:
 420                 switch (msg->header.cmd) {
 421
 422                 case NGM_EIFACE_SET:
 423                     {
 424                         if (msg->header.arglen != ETHER_ADDR_LEN) {
 425                                 error = EINVAL;
 426                                 break;
 427                         }
 428                         error = if_setlladdr(priv->ifp,
 429                             (u_char *)msg->data, ETHER_ADDR_LEN);
 430                         break;
 431                     }
 432
 433                 case NGM_EIFACE_GET_IFNAME:
 434                         NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
 435                         if (resp == NULL) {
 436                                 error = ENOMEM;
 437                                 break;
 438                         }
 439                         strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
 440                         break;
 441
 442                 case NGM_EIFACE_GET_IFADDRS:
 443                     {
 444                         struct ifaddr *ifa;
 445                         caddr_t ptr;
 446                         int buflen;
 447
 448 #define SA_SIZE(s)      ((s)->sa_len<sizeof(*(s))? sizeof(*(s)):(s)->sa_len)
 449
 450                         /* Determine size of response and allocate it */
 451                         buflen = 0;
 452                         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
 453                                 buflen += SA_SIZE(ifa->ifa_addr);
 454                         NG_MKRESPONSE(resp, msg, buflen, M_NOWAIT);
 455                         if (resp == NULL) {
 456                                 error = ENOMEM;
 457                                 break;
 458                         }
 459
 460                         /* Add addresses */
 461                         ptr = resp->data;
 462                         TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 463                                 const int len = SA_SIZE(ifa->ifa_addr);
 464
 465                                 if (buflen < len) {
 466                                         log(LOG_ERR, "%s: len changed?\n",
 467                                             ifp->if_xname);
 468                                         break;
 469                                 }
 470                                 bcopy(ifa->ifa_addr, ptr, len);
 471                                 ptr += len;
 472                                 buflen -= len;
 473                         }
 474                         break;
 475 #undef SA_SIZE
 476                     }
 477
 478                 default:
 479                         error = EINVAL;
 480                         break;
 481                 } /* end of inner switch() */
 482                 break;
 483         case NGM_FLOW_COOKIE:
 484                 switch (msg->header.cmd) {
 485                 case NGM_LINK_IS_UP:
 486                         if_link_state_change(ifp, LINK_STATE_UP);
 487                         break;
 488                 case NGM_LINK_IS_DOWN:
 489                         if_link_state_change(ifp, LINK_STATE_DOWN);
 490                         break;
 491                 default:
 492                         break;
 493                 }
 494                 break;
 495         default:
 496                 error = EINVAL;
 497                 break;
 498         }
 499         NG_RESPOND_MSG(error, node, item, resp);
 500         NG_FREE_MSG(msg);
 501         return (error);
 502 }
 503
 504 /*
 505  * Receive data from a hook. Pass the packet to the ether_input routine.
 506  */
 507 static int
 508 ng_eiface_rcvdata(hook_p hook, item_p item)
 509 {
 510         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 511         struct ifnet *const ifp = priv->ifp;
 512         struct mbuf *m;
 513
 514         NGI_GET_M(item, m);
 515         NG_FREE_ITEM(item);
 516
 517         if (!((ifp->if_flags & IFF_UP) &&
 518             (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
 519                 NG_FREE_M(m);
 520                 return (ENETDOWN);
 521         }
 522
 523         if (m->m_len < ETHER_HDR_LEN) {
 524                 m = m_pullup(m, ETHER_HDR_LEN);
 525                 if (m == NULL)
 526                         return (EINVAL);
 527         }
 528
 529         /* Note receiving interface */
 530         m->m_pkthdr.rcvif = ifp;
 531
 532         /* Update interface stats */
 533         ifp->if_ipackets++;
 534
 535         (*ifp->if_input)(ifp, m);
 536
 537         /* Done */
 538         return (0);
 539 }
 540
 541 /*
 542  * Shutdown processing.
 543  */
 544 static int
 545 ng_eiface_rmnode(node_p node)
 546 {
 547         const priv_p priv = NG_NODE_PRIVATE(node);
 548         struct ifnet *const ifp = priv->ifp;
 549
 550         ether_ifdetach(ifp);
 551         if_free(ifp);
 552         free_unr(ng_eiface_unit, priv->unit);
 553         FREE(priv, M_NETGRAPH);
 554         NG_NODE_SET_PRIVATE(node, NULL);
 555         NG_NODE_UNREF(node);
 556         return (0);
 557 }
 558
 559 /*
 560  * Hook disconnection
 561  */
 562 static int
 563 ng_eiface_disconnect(hook_p hook)
 564 {
 565         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 566
 567         priv->ether = NULL;
 568         return (0);
 569 }
 570
 571 /*
 572  * Handle loading and unloading for this node type.
 573  */
 574 static int
 575 ng_eiface_mod_event(module_t mod, int event, void *data)
 576 {
 577         int error = 0;
 578
 579         switch (event) {
 580         case MOD_LOAD:
 581                 ng_eiface_unit = new_unrhdr(0, 0xffff, NULL);
 582                 break;
 583         case MOD_UNLOAD:
 584                 delete_unrhdr(ng_eiface_unit);
 585                 break;
 586         default:
 587                 error = EOPNOTSUPP;
 588                 break;
 589         }
 590         return (error);
 591 }