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 #include "dhcpd.h"
  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
  72     if (!AdapterDiscover())
  73          return;
  74
  75     ApiLock();
  76
  77     do {
  78         /*
  79          * Call any expired timeouts, and then if there's still
  80          * a timeout registered, time out the select call then.
  81          */
  82         time(&cur_time);
  83
  84         if (timeouts) {
  85             struct timeout *t;
  86
  87             if (timeouts->when <= cur_time) {
  88                 t = timeouts;
  89                 timeouts = timeouts->next;
  90                 (*(t->func))(t->what);
  91                 t->next = free_timeouts;
  92                 free_timeouts = t;
  93                 continue;
  94             }
  95
  96             /*
  97              * Figure timeout in milliseconds, and check for
  98              * potential overflow, so we can cram into an
  99              * int for poll, while not polling with a
 100              * negative timeout and blocking indefinitely.
 101              */
 102             howlong = timeouts->when - cur_time;
 103             if (howlong > INT_MAX / 1000)
 104                 howlong = INT_MAX / 1000;
 105             to_msec = howlong * 1000;
 106         } else
 107             to_msec = 5000;
 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         if (protocols)
 122             count = select(0, &fds, NULL, NULL, &timeval);
 123         else {
 124             Sleep(to_msec);
 125             count = 0;
 126         }
 127
 128         ApiLock();
 129
 130         DH_DbgPrint(MID_TRACE,("Select: %d\n", count));
 131
 132         /* Not likely to be transitory... */
 133         if (count == SOCKET_ERROR) {
 134             err = WSAGetLastError();
 135             error("poll: %d", err);
 136             break;
 137         }
 138
 139         for (l = protocols; l; l = l->next) {
 140             struct interface_info *ip;
 141             ip = l->local;
 142             if (FD_ISSET(l->fd, &fds)) {
 143                 if (ip && (l->handler != got_one ||
 144                            !ip->dead)) {
 145                     DH_DbgPrint(MID_TRACE,("Handling %x\n", l));
 146                     (*(l->handler))(l);
 147                 }
 148             }
 149         }
 150     } while (1);
 151
 152     ApiUnlock();
 153 }
 154
 155 void
 156 got_one(struct protocol *l)
 157 {
 158     struct sockaddr_in from;
 159     struct hardware hfrom;
 160     struct iaddr ifrom;
 161     ssize_t result;
 162     union {
 163         /*
 164          * Packet input buffer.  Must be as large as largest
 165          * possible MTU.
 166          */
 167         unsigned char packbuf[4095];
 168         struct dhcp_packet packet;
 169     } u;
 170     struct interface_info *ip = l->local;
 171     PDHCP_ADAPTER adapter;
 172
 173     if ((result = receive_packet(ip, u.packbuf, sizeof(u), &from,
 174                                  &hfrom)) == -1) {
 175         warning("receive_packet failed on %s: %d", ip->name,
 176                 WSAGetLastError());
 177         ip->errors++;
 178         if (ip->errors > 20) {
 179             /* our interface has gone away. */
 180             warning("Interface %s no longer appears valid.",
 181                     ip->name);
 182             ip->dead = 1;
 183             closesocket(l->fd);
 184             remove_protocol(l);
 185             adapter = AdapterFindInfo(ip);
 186             if (adapter) {
 187                 RemoveEntryList(&adapter->ListEntry);
 188                 free(adapter);
 189             }
 190         }
 191         return;
 192     }
 193     if (result == 0)
 194         return;
 195
 196     if (bootp_packet_handler) {
 197         ifrom.len = 4;
 198         memcpy(ifrom.iabuf, &from.sin_addr, ifrom.len);
 199
 200
 201         adapter = AdapterFindByHardwareAddress(u.packet.chaddr,
 202                                                u.packet.hlen);
 203
 204         if (!adapter) {
 205             warning("Discarding packet with a non-matching target physical address\n");
 206             return;
 207         }
 208
 209         (*bootp_packet_handler)(&adapter->DhclientInfo, &u.packet, result,
 210                                 from.sin_port, ifrom, &hfrom);
 211     }
 212 }
 213
 214 void
 215 add_timeout(time_t when, void (*where)(void *), void *what)
 216 {
 217     struct timeout *t, *q;
 218
 219     DH_DbgPrint(MID_TRACE,("Adding timeout %x %p %x\n", when, where, what));
 220     /* See if this timeout supersedes an existing timeout. */
 221     t = NULL;
 222     for (q = timeouts; q; q = q->next) {
 223         if (q->func == where && q->what == what) {
 224             if (t)
 225                 t->next = q->next;
 226             else
 227                 timeouts = q->next;
 228             break;
 229         }
 230         t = q;
 231     }
 232
 233     /* If we didn't supersede a timeout, allocate a timeout
 234        structure now. */
 235     if (!q) {
 236         if (free_timeouts) {
 237             q = free_timeouts;
 238             free_timeouts = q->next;
 239             q->func = where;
 240             q->what = what;
 241         } else {
 242             q = malloc(sizeof(struct timeout));
 243             if (!q) {
 244                 error("Can't allocate timeout structure!");
 245                 return;
 246             }
 247             q->func = where;
 248             q->what = what;
 249         }
 250     }
 251
 252     q->when = when;
 253
 254     /* Now sort this timeout into the timeout list. */
 255
 256     /* Beginning of list? */
 257     if (!timeouts || timeouts->when > q->when) {
 258         q->next = timeouts;
 259         timeouts = q;
 260         return;
 261     }
 262
 263     /* Middle of list? */
 264     for (t = timeouts; t->next; t = t->next) {
 265         if (t->next->when > q->when) {
 266             q->next = t->next;
 267             t->next = q;
 268             return;
 269         }
 270     }
 271
 272     /* End of list. */
 273     t->next = q;
 274     q->next = NULL;
 275 }
 276
 277 void
 278 cancel_timeout(void (*where)(void *), void *what)
 279 {
 280     struct timeout *t, *q;
 281
 282     /* Look for this timeout on the list, and unlink it if we find it. */
 283     t = NULL;
 284     for (q = timeouts; q; q = q->next) {
 285         if (q->func == where && q->what == what) {
 286             if (t)
 287                 t->next = q->next;
 288             else
 289                 timeouts = q->next;
 290             break;
 291         }
 292         t = q;
 293     }
 294
 295     /* If we found the timeout, put it on the free list. */
 296     if (q) {
 297         q->next = free_timeouts;
 298         free_timeouts = q;
 299     }
 300 }
 301
 302 /* Add a protocol to the list of protocols... */
 303 void
 304 add_protocol(char *name, int fd, void (*handler)(struct protocol *),
 305              void *local)
 306 {
 307     struct protocol *p;
 308
 309     p = malloc(sizeof(*p));
 310     if (!p)
 311         error("can't allocate protocol struct for %s", name);
 312
 313     p->fd = fd;
 314     p->handler = handler;
 315     p->local = local;
 316     p->next = protocols;
 317     protocols = p;
 318 }
 319
 320 void
 321 remove_protocol(struct protocol *proto)
 322 {
 323     struct protocol *p, *next, *prev;
 324
 325     prev = NULL;
 326     for (p = protocols; p; p = next) {
 327         next = p->next;
 328         if (p == proto) {
 329             if (prev)
 330                 prev->next = p->next;
 331             else
 332                 protocols = p->next;
 333             free(p);
 334         }
 335     }
 336 }
 337
 338 struct protocol *
 339 find_protocol_by_adapter(struct interface_info *info)
 340 {
 341     struct protocol *p;
 342
 343     for( p = protocols; p; p = p->next ) {
 344         if( p->local == (void *)info ) return p;
 345     }
 346
 347     return NULL;
 348 }
 349
 350 int
 351 interface_link_status(char *ifname)
 352 {
 353     return (1);
 354 }