reactos/dll/win32/dhcpcsvc/dhcp/dispatch.c

   1 /*      $OpenBSD: dispatch.c,v 1.31 2004/09/21 04:07:03 david Exp $     */
   2
   3 /*
   4  * Copyright 2004 Henning Brauer <henning@openbsd.org>
   5  * Copyright (c) 1995, 1996, 1997, 1998, 1999
   6  * The Internet Software Consortium.   All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of The Internet Software Consortium nor the names
  18  *    of its contributors may be used to endorse or promote products derived
  19  *    from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
  22  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
  23  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25  * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
  26  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  27  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  28  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  29  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  30  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * This software has been written for the Internet Software Consortium
  36  * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
  37  * Enterprises.  To learn more about the Internet Software Consortium,
  38  * see ``http://www.vix.com/isc''.  To learn more about Vixie
  39  * Enterprises, see ``http://www.vix.com''.
  40  */
  41
  42 #include "rosdhcp.h"
  43
  44 //#include <sys/ioctl.h>
  45
  46 //#include <net/if_media.h>
  47 //#include <ifaddrs.h>
  48 //#include <poll.h>
  49
  50 extern SOCKET DhcpSocket;
  51 HANDLE AdapterStateChangedEvent = NULL;
  52 struct protocol *protocols = NULL;
  53 struct timeout *timeouts = NULL;
  54 static struct timeout *free_timeouts = NULL;
  55 void (*bootp_packet_handler)(struct interface_info *,
  56                              struct dhcp_packet *, int, unsigned int,
  57                              struct iaddr, struct hardware *);
  58
  59 /*
  60  * Wait for packets to come in using poll().  When a packet comes in,
  61  * call receive_packet to receive the packet and possibly strip hardware
  62  * addressing information from it, and then call through the
  63  * bootp_packet_handler hook to try to do something with it.
  64  */
  65 void
  66 dispatch(void)
  67 {
  68     int count, to_msec;
  69     struct protocol *l;
  70     time_t howlong, cur_time;
  71     HANDLE Events[2];
  72     int EventCount = 1;
  73
  74     Events[0] = StartAdapterDiscovery();
  75     if (!Events[0])
  76          return;
  77     AdapterStateChangedEvent = Events[0];
  78
  79     Events[1] = WSA_INVALID_EVENT;
  80
  81     ApiLock();
  82
  83     do {
  84         /*
  85          * Call any expired timeouts, and then if there's still
  86          * a timeout registered, time out the select call then.
  87          */
  88         time(&cur_time);
  89
  90         if (timeouts)
  91         {
  92             struct timeout *t;
  93
  94             if (timeouts->when <= cur_time) {
  95                 t = timeouts;
  96                 timeouts = timeouts->next;
  97                 (*(t->func))(t->what);
  98                 t->next = free_timeouts;
  99                 free_timeouts = t;
 100                 continue;
 101             }
 102
 103             /*
 104              * Figure timeout in milliseconds, and check for
 105              * potential overflow, so we can cram into an
 106              * int for poll, while not polling with a
 107              * negative timeout and blocking indefinitely.
 108              */
 109             howlong = timeouts->when - cur_time;
 110             if (howlong > INT_MAX / 1000)
 111                 howlong = INT_MAX / 1000;
 112             to_msec = howlong * 1000;
 113         }
 114         else
 115         {
 116             to_msec = INFINITE;
 117         }
 118
 119         if (Events[1] == WSA_INVALID_EVENT && DhcpSocket != INVALID_SOCKET)
 120         {
 121             Events[1] = WSACreateEvent();
 122             if (Events[1] != WSA_INVALID_EVENT)
 123             {
 124                 count = WSAEventSelect(DhcpSocket, Events[1], FD_READ | FD_CLOSE);
 125                 if (count != NO_ERROR)
 126                 {
 127                     WSACloseEvent(Events[1]);
 128                     Events[1] = WSA_INVALID_EVENT;
 129                 }
 130                 else
 131                 {
 132                     EventCount = 2;
 133                 }
 134             }
 135         }
 136         else if (Events[1] != WSA_INVALID_EVENT && DhcpSocket == INVALID_SOCKET)
 137         {
 138             WSACloseEvent(Events[1]);
 139             Events[1] = WSA_INVALID_EVENT;
 140
 141             EventCount = 1;
 142         }
 143
 144         ApiUnlock();
 145         count = WaitForMultipleObjects(EventCount,
 146                                        Events,
 147                                        FALSE,
 148                                        to_msec);
 149         ApiLock();
 150         if (count == WAIT_OBJECT_0)
 151         {
 152             /* Adapter state change */
 153             continue;
 154         }
 155         else if (count == WAIT_OBJECT_0 + 1)
 156         {
 157             /* Packet received */
 158
 159             /* WSA events are manual reset events */
 160             WSAResetEvent(Events[1]);
 161         }
 162         else
 163         {
 164             /* Timeout */
 165             continue;
 166         }
 167
 168         for (l = protocols; l; l = l->next) {
 169             struct interface_info *ip;
 170             ip = l->local;
 171             if (ip && (l->handler != got_one ||
 172                         !ip->dead)) {
 173                 DH_DbgPrint(MID_TRACE,("Handling %x\n", l));
 174                 (*(l->handler))(l);
 175             }
 176         }
 177     } while (1);
 178
 179     AdapterStateChangedEvent = NULL;
 180     CloseHandle(Events[0]);
 181     WSACloseEvent(Events[1]);
 182
 183     ApiUnlock();
 184 }
 185
 186 void
 187 got_one(struct protocol *l)
 188 {
 189     struct sockaddr_in from;
 190     struct hardware hfrom;
 191     struct iaddr ifrom;
 192     ssize_t result;
 193     union {
 194         /*
 195          * Packet input buffer.  Must be as large as largest
 196          * possible MTU.
 197          */
 198         unsigned char packbuf[4095];
 199         struct dhcp_packet packet;
 200     } u;
 201     struct interface_info *ip = l->local;
 202     PDHCP_ADAPTER adapter;
 203
 204     if ((result = receive_packet(ip, u.packbuf, sizeof(u), &from,
 205                                  &hfrom)) == -1) {
 206         warning("receive_packet failed on %s: %d", ip->name,
 207                 WSAGetLastError());
 208         ip->errors++;
 209         if (ip->errors > 20) {
 210             /* our interface has gone away. */
 211             warning("Interface %s no longer appears valid.",
 212                     ip->name);
 213             ip->dead = 1;
 214             closesocket(l->fd);
 215             remove_protocol(l);
 216             adapter = AdapterFindInfo(ip);
 217             if (adapter) {
 218                 RemoveEntryList(&adapter->ListEntry);
 219                 free(adapter);
 220             }
 221         }
 222         return;
 223     }
 224     if (result == 0)
 225         return;
 226
 227     if (bootp_packet_handler) {
 228         ifrom.len = 4;
 229         memcpy(ifrom.iabuf, &from.sin_addr, ifrom.len);
 230
 231
 232         adapter = AdapterFindByHardwareAddress(u.packet.chaddr,
 233                                                u.packet.hlen);
 234
 235         if (!adapter) {
 236             warning("Discarding packet with a non-matching target physical address\n");
 237             return;
 238         }
 239
 240         (*bootp_packet_handler)(&adapter->DhclientInfo, &u.packet, result,
 241                                 from.sin_port, ifrom, &hfrom);
 242     }
 243 }
 244
 245 void
 246 add_timeout(time_t when, void (*where)(void *), void *what)
 247 {
 248     struct timeout *t, *q;
 249
 250     DH_DbgPrint(MID_TRACE,("Adding timeout %x %p %x\n", when, where, what));
 251     /* See if this timeout supersedes an existing timeout. */
 252     t = NULL;
 253     for (q = timeouts; q; q = q->next) {
 254         if (q->func == where && q->what == what) {
 255             if (t)
 256                 t->next = q->next;
 257             else
 258                 timeouts = q->next;
 259             break;
 260         }
 261         t = q;
 262     }
 263
 264     /* If we didn't supersede a timeout, allocate a timeout
 265        structure now. */
 266     if (!q) {
 267         if (free_timeouts) {
 268             q = free_timeouts;
 269             free_timeouts = q->next;
 270             q->func = where;
 271             q->what = what;
 272         } else {
 273             q = malloc(sizeof(struct timeout));
 274             if (!q) {
 275                 error("Can't allocate timeout structure!");
 276                 return;
 277             }
 278             q->func = where;
 279             q->what = what;
 280         }
 281     }
 282
 283     q->when = when;
 284
 285     /* Now sort this timeout into the timeout list. */
 286
 287     /* Beginning of list? */
 288     if (!timeouts || timeouts->when > q->when) {
 289         q->next = timeouts;
 290         timeouts = q;
 291         return;
 292     }
 293
 294     /* Middle of list? */
 295     for (t = timeouts; t->next; t = t->next) {
 296         if (t->next->when > q->when) {
 297             q->next = t->next;
 298             t->next = q;
 299             return;
 300         }
 301     }
 302
 303     /* End of list. */
 304     t->next = q;
 305     q->next = NULL;
 306 }
 307
 308 void
 309 cancel_timeout(void (*where)(void *), void *what)
 310 {
 311     struct timeout *t, *q;
 312
 313     /* Look for this timeout on the list, and unlink it if we find it. */
 314     t = NULL;
 315     for (q = timeouts; q; q = q->next) {
 316         if (q->func == where && q->what == what) {
 317             if (t)
 318                 t->next = q->next;
 319             else
 320                 timeouts = q->next;
 321             break;
 322         }
 323         t = q;
 324     }
 325
 326     /* If we found the timeout, put it on the free list. */
 327     if (q) {
 328         q->next = free_timeouts;
 329         free_timeouts = q;
 330     }
 331 }
 332
 333 /* Add a protocol to the list of protocols... */
 334 void
 335 add_protocol(char *name, int fd, void (*handler)(struct protocol *),
 336              void *local)
 337 {
 338     struct protocol *p;
 339
 340     p = malloc(sizeof(*p));
 341     if (!p)
 342         error("can't allocate protocol struct for %s", name);
 343
 344     p->fd = fd;
 345     p->handler = handler;
 346     p->local = local;
 347     p->next = protocols;
 348     protocols = p;
 349 }
 350
 351 void
 352 remove_protocol(struct protocol *proto)
 353 {
 354     struct protocol *p, *next, *prev;
 355     struct interface_info *ip = proto->local;
 356     struct timeout *t, *q, *u;
 357
 358     t = NULL;
 359     q = timeouts;
 360     while (q != NULL)
 361     {
 362         /* Remove all timeouts for this protocol */
 363         if (q->what == ip)
 364         {
 365             /* Unlink the timeout from previous */
 366             if (t)
 367                 t->next = q->next;
 368             else
 369                 timeouts = q->next;
 370
 371             /* Advance to the next timeout */
 372             u = q->next;
 373
 374             /* Add it to the free list */
 375             q->next = free_timeouts;
 376             free_timeouts = q;
 377         }
 378         else
 379         {
 380             /* Advance to the next timeout */
 381             u = q->next;
 382
 383             /* Update the previous pointer */
 384             t = q;
 385         }
 386
 387         /* Advance */
 388         q = u;
 389     }
 390
 391     prev = NULL;
 392     for (p = protocols; p; p = next) {
 393         next = p->next;
 394         if (p == proto) {
 395             if (prev)
 396                 prev->next = p->next;
 397             else
 398                 protocols = p->next;
 399             free(p);
 400         }
 401     }
 402 }
 403
 404 struct protocol *
 405 find_protocol_by_adapter(struct interface_info *info)
 406 {
 407     struct protocol *p;
 408
 409     for( p = protocols; p; p = p->next ) {
 410         if( p->local == (void *)info ) return p;
 411     }
 412
 413     return NULL;
 414 }
 415
 416 int
 417 interface_link_status(char *ifname)
 418 {
 419     return (1);
 420 }