sys/netgraph7/eiface/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/sockio.h>
  38 #include <sys/socket.h>
  39 #include <sys/syslog.h>
  40
  41 #include <net/if.h>
  42 #include <net/if_types.h>
  43 #include <net/ifq_var.h>
  44 #include <net/netisr.h>
  45 #include <net/route.h>
  46
  47 #include <netgraph7/netgraph.h>
  48 #include <netgraph7/ng_message.h>
  49 #include <netgraph7/ng_parse.h>
  50 #include "ng_eiface.h"
  51
  52 #include <net/bpf.h>
  53 #include <net/ethernet.h>
  54 #include <net/if_arp.h>
  55
  56 static const struct ng_cmdlist ng_eiface_cmdlist[] = {
  57         {
  58           NGM_EIFACE_COOKIE,
  59           NGM_EIFACE_GET_IFNAME,
  60           "getifname",
  61           NULL,
  62           &ng_parse_string_type
  63         },
  64         {
  65           NGM_EIFACE_COOKIE,
  66           NGM_EIFACE_SET,
  67           "set",
  68           &ng_parse_enaddr_type,
  69           NULL
  70         },
  71         { 0 }
  72 };
  73
  74 /* Node private data */
  75 struct ng_eiface_private {
  76         struct ifnet    *ifp;           /* per-interface network data */
  77         int             unit;           /* Interface unit number */
  78         node_p          node;           /* Our netgraph node */
  79         hook_p          ether;          /* Hook for ethernet stream */
  80 };
  81 typedef struct ng_eiface_private *priv_p;
  82
  83 /* Interface methods */
  84 static void     ng_eiface_init(void *xsc);
  85 static void     ng_eiface_start(struct ifnet *ifp, struct ifaltq_subque *);
  86 static int      ng_eiface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data,
  87                                 struct ucred *cr);
  88 #ifdef DEBUG
  89 static void     ng_eiface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
  90 #endif
  91
  92 /* Netgraph methods */
  93 static int              ng_eiface_mod_event(module_t, int, void *);
  94 static ng_constructor_t ng_eiface_constructor;
  95 static ng_rcvmsg_t      ng_eiface_rcvmsg;
  96 static ng_shutdown_t    ng_eiface_rmnode;
  97 static ng_newhook_t     ng_eiface_newhook;
  98 static ng_rcvdata_t     ng_eiface_rcvdata;
  99 static ng_disconnect_t  ng_eiface_disconnect;
 100
 101 /* Node type descriptor */
 102 static struct ng_type typestruct = {
 103         .version =      NG_ABI_VERSION,
 104         .name =         NG_EIFACE_NODE_TYPE,
 105         .mod_event =    ng_eiface_mod_event,
 106         .constructor =  ng_eiface_constructor,
 107         .rcvmsg =       ng_eiface_rcvmsg,
 108         .shutdown =     ng_eiface_rmnode,
 109         .newhook =      ng_eiface_newhook,
 110         .rcvdata =      ng_eiface_rcvdata,
 111         .disconnect =   ng_eiface_disconnect,
 112         .cmdlist =      ng_eiface_cmdlist
 113 };
 114 NETGRAPH_INIT(eiface, &typestruct);
 115
 116 static int ng_eiface_next_unit;
 117
 118 /************************************************************************
 119                         INTERFACE STUFF
 120  ************************************************************************/
 121
 122 /*
 123  * Process an ioctl for the virtual interface
 124  */
 125 static int
 126 ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data, struct ucred *cr)
 127 {
 128         struct ifreq *const ifr = (struct ifreq *)data;
 129         int error = 0;
 130
 131 #ifdef DEBUG
 132         ng_eiface_print_ioctl(ifp, command, data);
 133 #endif
 134         crit_enter();
 135         switch (command) {
 136
 137         /* These two are mostly handled at a higher layer */
 138         case SIOCSIFADDR:
 139                 error = ether_ioctl(ifp, command, data);
 140                 break;
 141         case SIOCGIFADDR:
 142                 break;
 143
 144         /* Set flags */
 145         case SIOCSIFFLAGS:
 146                 /*
 147                  * If the interface is marked up and stopped, then start it.
 148                  * If it is marked down and running, then stop it.
 149                  */
 150                 if (ifp->if_flags & IFF_UP) {
 151                         if (!(ifp->if_flags & IFF_RUNNING)) {
 152                                 ifq_clr_oactive(&ifp->if_snd);
 153                                 ifp->if_flags |= IFF_RUNNING;
 154                         }
 155                 } else {
 156                         if (ifp->if_flags & IFF_RUNNING) {
 157                                 ifq_clr_oactive(&ifp->if_snd);
 158                                 ifp->if_flags &= ~(IFF_RUNNING);
 159                         }
 160                 }
 161                 break;
 162
 163         /* Set the interface MTU */
 164         case SIOCSIFMTU:
 165                 if (ifr->ifr_mtu > NG_EIFACE_MTU_MAX ||
 166                     ifr->ifr_mtu < NG_EIFACE_MTU_MIN)
 167                         error = EINVAL;
 168                 else
 169                         ifp->if_mtu = ifr->ifr_mtu;
 170                 break;
 171
 172         /* Stuff that's not supported */
 173         case SIOCADDMULTI:
 174         case SIOCDELMULTI:
 175                 error = 0;
 176                 break;
 177         case SIOCSIFPHYS:
 178                 error = EOPNOTSUPP;
 179                 break;
 180
 181         default:
 182                 error = EINVAL;
 183                 break;
 184         }
 185         crit_exit();
 186         return (error);
 187 }
 188
 189 static void
 190 ng_eiface_init(void *xsc)
 191 {
 192         priv_p sc = xsc;
 193         struct ifnet *ifp = sc->ifp;
 194
 195         crit_enter();
 196
 197         ifp->if_flags |= IFF_RUNNING;
 198         ifq_clr_oactive(&ifp->if_snd);
 199
 200         crit_exit();
 201
 202 }
 203
 204 /*
 205  * We simply relay the packet to the "ether" hook, if it is connected.
 206  * We have been through the netgraph locking and are guaranteed to
 207  * be the only code running in this node at this time.
 208  */
 209 static void
 210 ng_eiface_start2(node_p node, hook_p hook, void *arg1, int arg2)
 211 {
 212         struct ifnet *ifp = arg1;
 213         const priv_p priv = (priv_p)ifp->if_softc;
 214         int error = 0;
 215         struct mbuf *m;
 216
 217         /* Check interface flags */
 218
 219         if (!((ifp->if_flags & IFF_UP) &&
 220             (ifp->if_flags & IFF_RUNNING)))
 221                 return;
 222
 223         for (;;) {
 224                 /*
 225                  * Grab a packet to transmit.
 226                  */
 227                 m = ifq_dequeue(&ifp->if_snd);
 228
 229                 /* If there's nothing to send, break. */
 230                 if (m == NULL)
 231                         break;
 232
 233                 /*
 234                  * Berkeley packet filter.
 235                  * Pass packet to bpf if there is a listener.
 236                  * XXX is this safe? locking?
 237                  */
 238                 BPF_MTAP(ifp, m);
 239
 240                 if (ifp->if_flags & IFF_MONITOR) {
 241                         ifp->if_ipackets++;
 242                         m_freem(m);
 243                         continue;
 244                 }
 245
 246                 /*
 247                  * Send packet; if hook is not connected, mbuf will get
 248                  * freed.
 249                  */
 250                 NG_SEND_DATA_ONLY(error, priv->ether, m);
 251
 252                 /* Update stats */
 253                 if (error == 0)
 254                         ifp->if_opackets++;
 255                 else
 256                         ifp->if_oerrors++;
 257         }
 258
 259         ifq_clr_oactive(&ifp->if_snd);
 260
 261         return;
 262 }
 263
 264 /*
 265  * This routine is called to deliver a packet out the interface.
 266  * We simply queue the netgraph version to be called when netgraph locking
 267  * allows it to happen.
 268  * Until we know what the rest of the networking code is doing for
 269  * locking, we don't know how we will interact with it.
 270  * Take comfort from the fact that the ifnet struct is part of our
 271  * private info and can't go away while we are queued.
 272  * [Though we don't know it is still there now....]
 273  * it is possible we don't gain anything from this because
 274  * we would like to get the mbuf and queue it as data
 275  * somehow, but we can't and if we did would we solve anything?
 276  */
 277 static void
 278 ng_eiface_start(struct ifnet *ifp, struct ifaltq_subque *ifsq __unused)
 279 {
 280
 281         const priv_p priv = (priv_p)ifp->if_softc;
 282
 283         /* Don't do anything if output is active */
 284         if (ifq_is_oactive(&ifp->if_snd))
 285                 return;
 286
 287         ifq_set_oactive(&ifp->if_snd);
 288
 289         if (ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0) != 0)
 290                 ifq_clr_oactive(&ifp->if_snd);
 291 }
 292
 293 #ifdef DEBUG
 294 /*
 295  * Display an ioctl to the virtual interface
 296  */
 297
 298 static void
 299 ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
 300 {
 301         char *str;
 302
 303         switch (command & IOC_DIRMASK) {
 304         case IOC_VOID:
 305                 str = "IO";
 306                 break;
 307         case IOC_OUT:
 308                 str = "IOR";
 309                 break;
 310         case IOC_IN:
 311                 str = "IOW";
 312                 break;
 313         case IOC_INOUT:
 314                 str = "IORW";
 315                 break;
 316         default:
 317                 str = "IO??";
 318         }
 319         log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
 320             ifp->if_xname,
 321             str,
 322             IOCGROUP(command),
 323             command & 0xff,
 324             IOCPARM_LEN(command));
 325 }
 326 #endif /* DEBUG */
 327
 328 /************************************************************************
 329                         NETGRAPH NODE STUFF
 330  ************************************************************************/
 331
 332 /*
 333  * Constructor for a node
 334  */
 335 static int
 336 ng_eiface_constructor(node_p node)
 337 {
 338         struct ifnet *ifp;
 339         priv_p priv;
 340         u_char eaddr[6] = {0,0,0,0,0,0};
 341
 342         /* Allocate node and interface private structures */
 343         priv = kmalloc(sizeof(*priv), M_NETGRAPH,
 344                        M_WAITOK | M_NULLOK | M_ZERO);
 345         if (priv == NULL)
 346                 return (ENOMEM);
 347
 348         ifp = priv->ifp = if_alloc(IFT_ETHER);
 349         if (ifp == NULL) {
 350                 kfree(priv, M_NETGRAPH);
 351                 return (ENOSPC);
 352         }
 353
 354         /* Link them together */
 355         ifp->if_softc = priv;
 356
 357         /* Get an interface unit number */
 358         priv->unit = ng_eiface_next_unit++;
 359
 360         /* Link together node and private info */
 361         NG_NODE_SET_PRIVATE(node, priv);
 362         priv->node = node;
 363
 364         /* Initialize interface structure */
 365         if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
 366         ifp->if_init = ng_eiface_init;
 367 /*
 368         ifp->if_output = ether_output;
 369 */
 370         ifp->if_start = ng_eiface_start;
 371         ifp->if_ioctl = ng_eiface_ioctl;
 372         ifp->if_watchdog = NULL;
 373         ifq_set_maxlen(&ifp->if_snd, IFQ_MAXLEN);
 374         ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
 375
 376 #if 0
 377         /* Give this node name */
 378         bzero(ifname, sizeof(ifname));
 379         ksprintf(ifname, "if%s", ifp->if_xname);
 380         (void)ng_name_node(node, ifname);
 381 #endif
 382
 383         /* Attach the interface */
 384         ether_ifattach(ifp, eaddr, NULL);
 385
 386         /* Done */
 387         return (0);
 388 }
 389
 390 /*
 391  * Give our ok for a hook to be added
 392  */
 393 static int
 394 ng_eiface_newhook(node_p node, hook_p hook, const char *name)
 395 {
 396         priv_p priv = NG_NODE_PRIVATE(node);
 397         struct ifnet *ifp = priv->ifp;
 398
 399         if (strcmp(name, NG_EIFACE_HOOK_ETHER))
 400                 return (EPFNOSUPPORT);
 401         if (priv->ether != NULL)
 402                 return (EISCONN);
 403         priv->ether = hook;
 404         NG_HOOK_SET_PRIVATE(hook, &priv->ether);
 405
 406         ifp->if_link_state = LINK_STATE_UP;
 407         if_link_state_change(ifp);
 408
 409         return (0);
 410 }
 411
 412 /*
 413  * Receive a control message
 414  */
 415 static int
 416 ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
 417 {
 418         const priv_p priv = NG_NODE_PRIVATE(node);
 419         struct ifnet *const ifp = priv->ifp;
 420         struct ng_mesg *resp = NULL;
 421         int error = 0;
 422         struct ng_mesg *msg;
 423
 424         NGI_GET_MSG(item, msg);
 425         switch (msg->header.typecookie) {
 426         case NGM_EIFACE_COOKIE:
 427                 switch (msg->header.cmd) {
 428
 429                 case NGM_EIFACE_SET:
 430                     {
 431                         if (msg->header.arglen != ETHER_ADDR_LEN) {
 432                                 error = EINVAL;
 433                                 break;
 434                         }
 435                         error = if_setlladdr(priv->ifp,
 436                             (u_char *)msg->data, ETHER_ADDR_LEN);
 437                         break;
 438                     }
 439
 440                 case NGM_EIFACE_GET_IFNAME:
 441                         NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_WAITOK | M_NULLOK);
 442                         if (resp == NULL) {
 443                                 error = ENOMEM;
 444                                 break;
 445                         }
 446                         strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
 447                         break;
 448
 449                 case NGM_EIFACE_GET_IFADDRS:
 450                     {
 451                         struct ifaddr_container *ifac;
 452                         caddr_t ptr;
 453                         int buflen;
 454
 455 #define SA_SIZE(s)      RT_ROUNDUP((s)->sa_len)
 456
 457                         /* Determine size of response and allocate it */
 458                         buflen = 0;
 459                         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid],
 460                                       ifa_link) {
 461                                 /* Ignore marker */
 462                                 if (ifac->ifa->ifa_addr->sa_family == AF_UNSPEC)
 463                                         continue;
 464                                 buflen += SA_SIZE(ifac->ifa->ifa_addr);
 465                         }
 466                         NG_MKRESPONSE(resp, msg, buflen, M_WAITOK | M_NULLOK);
 467                         if (resp == NULL) {
 468                                 error = ENOMEM;
 469                                 break;
 470                         }
 471
 472                         /* Add addresses */
 473                         ptr = resp->data;
 474                         TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid],
 475                                       ifa_link) {
 476                                 struct ifaddr *ifa = ifac->ifa;
 477                                 const int len = SA_SIZE(ifa->ifa_addr);
 478
 479                                 /* Ignore marker */
 480                                 if (ifa->ifa_addr->sa_family == AF_UNSPEC)
 481                                         continue;
 482
 483                                 if (buflen < len) {
 484                                         log(LOG_ERR, "%s: len changed?\n",
 485                                             ifp->if_xname);
 486                                         break;
 487                                 }
 488                                 bcopy(ifa->ifa_addr, ptr, len);
 489                                 ptr += len;
 490                                 buflen -= len;
 491                         }
 492                         break;
 493 #undef SA_SIZE
 494                     }
 495
 496                 default:
 497                         error = EINVAL;
 498                         break;
 499                 } /* end of inner switch() */
 500                 break;
 501         case NGM_FLOW_COOKIE:
 502                 switch (msg->header.cmd) {
 503                 case NGM_LINK_IS_UP:
 504                         ifp->if_link_state = LINK_STATE_UP;
 505                         if_link_state_change(ifp);
 506                         break;
 507                 case NGM_LINK_IS_DOWN:
 508                         ifp->if_link_state = LINK_STATE_DOWN;
 509                         if_link_state_change(ifp);
 510                         break;
 511                 default:
 512                         break;
 513                 }
 514                 break;
 515         default:
 516                 error = EINVAL;
 517                 break;
 518         }
 519         NG_RESPOND_MSG(error, node, item, resp);
 520         NG_FREE_MSG(msg);
 521         return (error);
 522 }
 523
 524 /*
 525  * Receive data from a hook. Pass the packet to the ether_input routine.
 526  */
 527 static int
 528 ng_eiface_rcvdata(hook_p hook, item_p item)
 529 {
 530         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 531         struct ifnet *const ifp = priv->ifp;
 532         struct mbuf *m;
 533
 534         NGI_GET_M(item, m);
 535         NG_FREE_ITEM(item);
 536
 537         if (!((ifp->if_flags & IFF_UP) &&
 538             (ifp->if_flags & IFF_RUNNING))) {
 539                 NG_FREE_M(m);
 540                 return (ENETDOWN);
 541         }
 542
 543         if (m->m_len < ETHER_HDR_LEN) {
 544                 m = m_pullup(m, ETHER_HDR_LEN);
 545                 if (m == NULL)
 546                         return (EINVAL);
 547         }
 548
 549         /* Note receiving interface */
 550         m->m_pkthdr.rcvif = ifp;
 551
 552         /* Update interface stats */
 553         ifp->if_ipackets++;
 554
 555         ifp->if_input(ifp, m, NULL, -1);
 556
 557         /* Done */
 558         return (0);
 559 }
 560
 561 /*
 562  * Shutdown processing.
 563  */
 564 static int
 565 ng_eiface_rmnode(node_p node)
 566 {
 567         const priv_p priv = NG_NODE_PRIVATE(node);
 568         struct ifnet *const ifp = priv->ifp;
 569
 570         ether_ifdetach(ifp);
 571         if_free(ifp);
 572         kfree(priv, M_NETGRAPH);
 573         NG_NODE_SET_PRIVATE(node, NULL);
 574         NG_NODE_UNREF(node);
 575         return (0);
 576 }
 577
 578 /*
 579  * Hook disconnection
 580  */
 581 static int
 582 ng_eiface_disconnect(hook_p hook)
 583 {
 584         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 585
 586         priv->ether = NULL;
 587         return (0);
 588 }
 589
 590 /*
 591  * Handle loading and unloading for this node type.
 592  */
 593 static int
 594 ng_eiface_mod_event(module_t mod, int event, void *data)
 595 {
 596         int error = 0;
 597
 598         switch (event) {
 599         case MOD_LOAD:
 600                 break;
 601         case MOD_UNLOAD:
 602                 break;
 603         default:
 604                 error = EOPNOTSUPP;
 605                 break;
 606         }
 607         return (error);
 608 }