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 struct protocol *protocols = NULL;
  51 struct timeout *timeouts = NULL;
  52 static struct timeout *free_timeouts = NULL;
  53 void (*bootp_packet_handler)(struct interface_info *,
  54                              struct dhcp_packet *, int, unsigned int,
  55                              struct iaddr, struct hardware *);
  56
  57 /*
  58  * Wait for packets to come in using poll().  When a packet comes in,
  59  * call receive_packet to receive the packet and possibly strip hardware
  60  * addressing information from it, and then call through the
  61  * bootp_packet_handler hook to try to do something with it.
  62  */
  63 void
  64 dispatch(void)
  65 {
  66     int count, to_msec, err;
  67     struct protocol *l;
  68     fd_set fds;
  69     time_t howlong, cur_time;
  70     struct timeval timeval;
  71     HANDLE AdapterStateChangedEvent;
  72
  73     AdapterStateChangedEvent = StartAdapterDiscovery();
  74     if (!AdapterStateChangedEvent)
  75          return;
  76
  77     ApiLock();
  78
  79     do {
  80         /*
  81          * Call any expired timeouts, and then if there's still
  82          * a timeout registered, time out the select call then.
  83          */
  84         time(&cur_time);
  85
  86         if (timeouts) {
  87             struct timeout *t;
  88
  89             if (timeouts->when <= cur_time) {
  90                 t = timeouts;
  91                 timeouts = timeouts->next;
  92                 (*(t->func))(t->what);
  93                 t->next = free_timeouts;
  94                 free_timeouts = t;
  95                 continue;
  96             }
  97
  98             /*
  99              * Figure timeout in milliseconds, and check for
 100              * potential overflow, so we can cram into an
 101              * int for poll, while not polling with a
 102              * negative timeout and blocking indefinitely.
 103              */
 104             howlong = timeouts->when - cur_time;
 105             if (howlong > INT_MAX / 1000)
 106                 howlong = INT_MAX / 1000;
 107             to_msec = howlong * 1000;
 108
 109             /* Set up the descriptors to be polled. */
 110             FD_ZERO(&fds);
 111
 112             for (l = protocols; l; l = l->next)
 113                  FD_SET(l->fd, &fds);
 114
 115             /* Wait for a packet or a timeout... XXX */
 116             timeval.tv_sec = to_msec / 1000;
 117             timeval.tv_usec = to_msec % 1000;
 118
 119             ApiUnlock();
 120
 121             count = select(0, &fds, NULL, NULL, &timeval);
 122
 123             ApiLock();
 124         }
 125         else
 126         {
 127             ApiUnlock();
 128             WaitForSingleObject(AdapterStateChangedEvent, INFINITE);
 129             ApiLock();
 130
 131             continue;
 132         }
 133
 134         DH_DbgPrint(MID_TRACE,("Select: %d\n", count));
 135
 136         /* Not likely to be transitory... */
 137         if (count == SOCKET_ERROR) {
 138             err = WSAGetLastError();
 139             error("poll: %d", err);
 140             break;
 141         }
 142
 143         for (l = protocols; l; l = l->next) {
 144             struct interface_info *ip;
 145             ip = l->local;
 146             if (FD_ISSET(l->fd, &fds)) {
 147                 if (ip && (l->handler != got_one ||
 148                            !ip->dead)) {
 149                     DH_DbgPrint(MID_TRACE,("Handling %x\n", l));
 150                     (*(l->handler))(l);
 151                 }
 152             }
 153         }
 154     } while (1);
 155
 156     CloseHandle(AdapterStateChangedEvent);
 157
 158     ApiUnlock();
 159 }
 160
 161 void
 162 got_one(struct protocol *l)
 163 {
 164     struct sockaddr_in from;
 165     struct hardware hfrom;
 166     struct iaddr ifrom;
 167     ssize_t result;
 168     union {
 169         /*
 170          * Packet input buffer.  Must be as large as largest
 171          * possible MTU.
 172          */
 173         unsigned char packbuf[4095];
 174         struct dhcp_packet packet;
 175     } u;
 176     struct interface_info *ip = l->local;
 177     PDHCP_ADAPTER adapter;
 178
 179     if ((result = receive_packet(ip, u.packbuf, sizeof(u), &from,
 180                                  &hfrom)) == -1) {
 181         warning("receive_packet failed on %s: %d", ip->name,
 182                 WSAGetLastError());
 183         ip->errors++;
 184         if (ip->errors > 20) {
 185             /* our interface has gone away. */
 186             warning("Interface %s no longer appears valid.",
 187                     ip->name);
 188             ip->dead = 1;
 189             closesocket(l->fd);
 190             remove_protocol(l);
 191             adapter = AdapterFindInfo(ip);
 192             if (adapter) {
 193                 RemoveEntryList(&adapter->ListEntry);
 194                 free(adapter);
 195             }
 196         }
 197         return;
 198     }
 199     if (result == 0)
 200         return;
 201
 202     if (bootp_packet_handler) {
 203         ifrom.len = 4;
 204         memcpy(ifrom.iabuf, &from.sin_addr, ifrom.len);
 205
 206
 207         adapter = AdapterFindByHardwareAddress(u.packet.chaddr,
 208                                                u.packet.hlen);
 209
 210         if (!adapter) {
 211             warning("Discarding packet with a non-matching target physical address\n");
 212             return;
 213         }
 214
 215         (*bootp_packet_handler)(&adapter->DhclientInfo, &u.packet, result,
 216                                 from.sin_port, ifrom, &hfrom);
 217     }
 218 }
 219
 220 void
 221 add_timeout(time_t when, void (*where)(void *), void *what)
 222 {
 223     struct timeout *t, *q;
 224
 225     DH_DbgPrint(MID_TRACE,("Adding timeout %x %p %x\n", when, where, what));
 226     /* See if this timeout supersedes an existing timeout. */
 227     t = NULL;
 228     for (q = timeouts; q; q = q->next) {
 229         if (q->func == where && q->what == what) {
 230             if (t)
 231                 t->next = q->next;
 232             else
 233                 timeouts = q->next;
 234             break;
 235         }
 236         t = q;
 237     }
 238
 239     /* If we didn't supersede a timeout, allocate a timeout
 240        structure now. */
 241     if (!q) {
 242         if (free_timeouts) {
 243             q = free_timeouts;
 244             free_timeouts = q->next;
 245             q->func = where;
 246             q->what = what;
 247         } else {
 248             q = malloc(sizeof(struct timeout));
 249             if (!q) {
 250                 error("Can't allocate timeout structure!");
 251                 return;
 252             }
 253             q->func = where;
 254             q->what = what;
 255         }
 256     }
 257
 258     q->when = when;
 259
 260     /* Now sort this timeout into the timeout list. */
 261
 262     /* Beginning of list? */
 263     if (!timeouts || timeouts->when > q->when) {
 264         q->next = timeouts;
 265         timeouts = q;
 266         return;
 267     }
 268
 269     /* Middle of list? */
 270     for (t = timeouts; t->next; t = t->next) {
 271         if (t->next->when > q->when) {
 272             q->next = t->next;
 273             t->next = q;
 274             return;
 275         }
 276     }
 277
 278     /* End of list. */
 279     t->next = q;
 280     q->next = NULL;
 281 }
 282
 283 void
 284 cancel_timeout(void (*where)(void *), void *what)
 285 {
 286     struct timeout *t, *q;
 287
 288     /* Look for this timeout on the list, and unlink it if we find it. */
 289     t = NULL;
 290     for (q = timeouts; q; q = q->next) {
 291         if (q->func == where && q->what == what) {
 292             if (t)
 293                 t->next = q->next;
 294             else
 295                 timeouts = q->next;
 296             break;
 297         }
 298         t = q;
 299     }
 300
 301     /* If we found the timeout, put it on the free list. */
 302     if (q) {
 303         q->next = free_timeouts;
 304         free_timeouts = q;
 305     }
 306 }
 307
 308 /* Add a protocol to the list of protocols... */
 309 void
 310 add_protocol(char *name, int fd, void (*handler)(struct protocol *),
 311              void *local)
 312 {
 313     struct protocol *p;
 314
 315     p = malloc(sizeof(*p));
 316     if (!p)
 317         error("can't allocate protocol struct for %s", name);
 318
 319     p->fd = fd;
 320     p->handler = handler;
 321     p->local = local;
 322     p->next = protocols;
 323     protocols = p;
 324 }
 325
 326 void
 327 remove_protocol(struct protocol *proto)
 328 {
 329     struct protocol *p, *next, *prev;
 330
 331     prev = NULL;
 332     for (p = protocols; p; p = next) {
 333         next = p->next;
 334         if (p == proto) {
 335             if (prev)
 336                 prev->next = p->next;
 337             else
 338                 protocols = p->next;
 339             free(p);
 340         }
 341     }
 342 }
 343
 344 struct protocol *
 345 find_protocol_by_adapter(struct interface_info *info)
 346 {
 347     struct protocol *p;
 348
 349     for( p = protocols; p; p = p->next ) {
 350         if( p->local == (void *)info ) return p;
 351     }
 352
 353     return NULL;
 354 }
 355
 356 int
 357 interface_link_status(char *ifname)
 358 {
 359     return (1);
 360 }