Darran Shepherd
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AutoIpNetStack
Net stack with AutoIP enabled
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autoip.c
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00001 /** 00002 * @file 00003 * AutoIP Automatic LinkLocal IP Configuration 00004 * 00005 */ 00006 00007 /* 00008 * 00009 * Copyright (c) 2007 Dominik Spies <kontakt@dspies.de> 00010 * All rights reserved. 00011 * 00012 * Redistribution and use in source and binary forms, with or without modification, 00013 * are permitted provided that the following conditions are met: 00014 * 00015 * 1. Redistributions of source code must retain the above copyright notice, 00016 * this list of conditions and the following disclaimer. 00017 * 2. Redistributions in binary form must reproduce the above copyright notice, 00018 * this list of conditions and the following disclaimer in the documentation 00019 * and/or other materials provided with the distribution. 00020 * 3. The name of the author may not be used to endorse or promote products 00021 * derived from this software without specific prior written permission. 00022 * 00023 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 00024 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 00025 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 00026 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 00027 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 00028 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 00029 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 00030 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 00031 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 00032 * OF SUCH DAMAGE. 00033 * 00034 * Author: Dominik Spies <kontakt@dspies.de> 00035 * 00036 * This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform 00037 * with RFC 3927. 00038 * 00039 * 00040 * Please coordinate changes and requests with Dominik Spies 00041 * <kontakt@dspies.de> 00042 */ 00043 00044 /******************************************************************************* 00045 * USAGE: 00046 * 00047 * define LWIP_AUTOIP 1 in your lwipopts.h 00048 * 00049 * If you don't use tcpip.c (so, don't call, you don't call tcpip_init): 00050 * - First, call autoip_init(). 00051 * - call autoip_tmr() all AUTOIP_TMR_INTERVAL msces, 00052 * that should be defined in autoip.h. 00053 * I recommend a value of 100. The value must divide 1000 with a remainder almost 0. 00054 * Possible values are 1000, 500, 333, 250, 200, 166, 142, 125, 111, 100 .... 00055 * 00056 * Without DHCP: 00057 * - Call autoip_start() after netif_add(). 00058 * 00059 * With DHCP: 00060 * - define LWIP_DHCP_AUTOIP_COOP 1 in your lwipopts.h. 00061 * - Configure your DHCP Client. 00062 * 00063 */ 00064 00065 #include "lwip/opt.h" 00066 00067 #if LWIP_AUTOIP /* don't build if not configured for use in lwipopts.h */ 00068 00069 #include "lwip/mem.h" 00070 #include "lwip/udp.h" 00071 #include "lwip/ip_addr.h" 00072 #include "lwip/netif.h" 00073 #include "lwip/autoip.h" 00074 #include "netif/etharp.h" 00075 00076 #include <stdlib.h> 00077 #include <string.h> 00078 00079 /* 169.254.0.0 */ 00080 #define AUTOIP_NET 0xA9FE0000 00081 /* 169.254.1.0 */ 00082 #define AUTOIP_RANGE_START (AUTOIP_NET | 0x0100) 00083 /* 169.254.254.255 */ 00084 #define AUTOIP_RANGE_END (AUTOIP_NET | 0xFEFF) 00085 00086 00087 /** Pseudo random macro based on netif informations. 00088 * You could use "rand()" from the C Library if you define LWIP_AUTOIP_RAND in lwipopts.h */ 00089 #ifndef LWIP_AUTOIP_RAND 00090 #define LWIP_AUTOIP_RAND(netif) ( (((u32_t)((netif->hwaddr[5]) & 0xff) << 24) | \ 00091 ((u32_t)((netif->hwaddr[3]) & 0xff) << 16) | \ 00092 ((u32_t)((netif->hwaddr[2]) & 0xff) << 8) | \ 00093 ((u32_t)((netif->hwaddr[4]) & 0xff))) + \ 00094 (netif->autoip?netif->autoip->tried_llipaddr:0)) 00095 #endif /* LWIP_AUTOIP_RAND */ 00096 00097 /** 00098 * Macro that generates the initial IP address to be tried by AUTOIP. 00099 * If you want to override this, define it to something else in lwipopts.h. 00100 */ 00101 #ifndef LWIP_AUTOIP_CREATE_SEED_ADDR 00102 #define LWIP_AUTOIP_CREATE_SEED_ADDR(netif) \ 00103 htonl(AUTOIP_RANGE_START + ((u32_t)(((u8_t)(netif->hwaddr[4])) | \ 00104 ((u32_t)((u8_t)(netif->hwaddr[5]))) << 8))) 00105 #endif /* LWIP_AUTOIP_CREATE_SEED_ADDR */ 00106 00107 /* static functions */ 00108 static void autoip_handle_arp_conflict(struct netif *netif); 00109 00110 /* creates a pseudo random LL IP-Address for a network interface */ 00111 static void autoip_create_addr(struct netif *netif, ip_addr_t *ipaddr); 00112 00113 /* sends an ARP probe */ 00114 static err_t autoip_arp_probe(struct netif *netif); 00115 00116 /* sends an ARP announce */ 00117 static err_t autoip_arp_announce(struct netif *netif); 00118 00119 /* configure interface for use with current LL IP-Address */ 00120 static err_t autoip_bind(struct netif *netif); 00121 00122 /* start sending probes for llipaddr */ 00123 static void autoip_start_probing(struct netif *netif); 00124 00125 /** 00126 * Initialize this module 00127 */ 00128 void 00129 autoip_init(void) 00130 { 00131 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_init()\n")); 00132 } 00133 00134 /** Set a statically allocated struct autoip to work with. 00135 * Using this prevents autoip_start to allocate it using mem_malloc. 00136 * 00137 * @param netif the netif for which to set the struct autoip 00138 * @param dhcp (uninitialised) dhcp struct allocated by the application 00139 */ 00140 void 00141 autoip_set_struct(struct netif *netif, struct autoip *autoip) 00142 { 00143 LWIP_ASSERT("netif != NULL", netif != NULL); 00144 LWIP_ASSERT("autoip != NULL", autoip != NULL); 00145 LWIP_ASSERT("netif already has a struct autoip set", netif->autoip == NULL); 00146 00147 /* clear data structure */ 00148 memset(autoip, 0, sizeof(struct autoip)); 00149 /* autoip->state = AUTOIP_STATE_OFF; */ 00150 netif->autoip = autoip; 00151 } 00152 00153 /** 00154 * Handle a IP address conflict after an ARP conflict detection 00155 */ 00156 static void 00157 autoip_handle_arp_conflict(struct netif *netif) 00158 { 00159 /* Somehow detect if we are defending or retreating */ 00160 unsigned char defend = 1; /* tbd */ 00161 00162 if(defend) { 00163 if(netif->autoip->lastconflict > 0) { 00164 /* retreat, there was a conflicting ARP in the last 00165 * DEFEND_INTERVAL seconds 00166 */ 00167 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00168 ("autoip_handle_arp_conflict(): we are defending, but in DEFEND_INTERVAL, retreating\n")); 00169 00170 /* TODO: close all TCP sessions */ 00171 autoip_start(netif); 00172 } else { 00173 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00174 ("autoip_handle_arp_conflict(): we are defend, send ARP Announce\n")); 00175 autoip_arp_announce(netif); 00176 netif->autoip->lastconflict = DEFEND_INTERVAL * AUTOIP_TICKS_PER_SECOND; 00177 } 00178 } else { 00179 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00180 ("autoip_handle_arp_conflict(): we do not defend, retreating\n")); 00181 /* TODO: close all TCP sessions */ 00182 autoip_start(netif); 00183 } 00184 } 00185 00186 /** 00187 * Create an IP-Address out of range 169.254.1.0 to 169.254.254.255 00188 * 00189 * @param netif network interface on which create the IP-Address 00190 * @param ipaddr ip address to initialize 00191 */ 00192 static void 00193 autoip_create_addr(struct netif *netif, ip_addr_t *ipaddr) 00194 { 00195 /* Here we create an IP-Address out of range 169.254.1.0 to 169.254.254.255 00196 * compliant to RFC 3927 Section 2.1 00197 * We have 254 * 256 possibilities */ 00198 00199 u32_t addr = ntohl(LWIP_AUTOIP_CREATE_SEED_ADDR(netif)); 00200 addr += netif->autoip->tried_llipaddr; 00201 addr = AUTOIP_NET | (addr & 0xffff); 00202 /* Now, 169.254.0.0 <= addr <= 169.254.255.255 */ 00203 00204 if (addr < AUTOIP_RANGE_START) { 00205 addr += AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1; 00206 } 00207 if (addr > AUTOIP_RANGE_END) { 00208 addr -= AUTOIP_RANGE_END - AUTOIP_RANGE_START + 1; 00209 } 00210 LWIP_ASSERT("AUTOIP address not in range", (addr >= AUTOIP_RANGE_START) && 00211 (addr <= AUTOIP_RANGE_END)); 00212 ip4_addr_set_u32(ipaddr, htonl(addr)); 00213 00214 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00215 ("autoip_create_addr(): tried_llipaddr=%"U16_F", %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", 00216 (u16_t)(netif->autoip->tried_llipaddr), ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), 00217 ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr))); 00218 } 00219 00220 /** 00221 * Sends an ARP probe from a network interface 00222 * 00223 * @param netif network interface used to send the probe 00224 */ 00225 static err_t 00226 autoip_arp_probe(struct netif *netif) 00227 { 00228 return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, ðbroadcast, 00229 (struct eth_addr *)netif->hwaddr, IP_ADDR_ANY, ðzero, 00230 &netif->autoip->llipaddr, ARP_REQUEST); 00231 } 00232 00233 /** 00234 * Sends an ARP announce from a network interface 00235 * 00236 * @param netif network interface used to send the announce 00237 */ 00238 static err_t 00239 autoip_arp_announce(struct netif *netif) 00240 { 00241 return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, ðbroadcast, 00242 (struct eth_addr *)netif->hwaddr, &netif->autoip->llipaddr, ðzero, 00243 &netif->autoip->llipaddr, ARP_REQUEST); 00244 } 00245 00246 /** 00247 * Configure interface for use with current LL IP-Address 00248 * 00249 * @param netif network interface to configure with current LL IP-Address 00250 */ 00251 static err_t 00252 autoip_bind(struct netif *netif) 00253 { 00254 struct autoip *autoip = netif->autoip; 00255 ip_addr_t sn_mask, gw_addr; 00256 00257 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, 00258 ("autoip_bind(netif=%p) %c%c%"U16_F" %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", 00259 (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num, 00260 ip4_addr1_16(&autoip->llipaddr), ip4_addr2_16(&autoip->llipaddr), 00261 ip4_addr3_16(&autoip->llipaddr), ip4_addr4_16(&autoip->llipaddr))); 00262 00263 IP4_ADDR(&sn_mask, 255, 255, 0, 0); 00264 IP4_ADDR(&gw_addr, 0, 0, 0, 0); 00265 00266 netif_set_ipaddr(netif, &autoip->llipaddr); 00267 netif_set_netmask(netif, &sn_mask); 00268 netif_set_gw(netif, &gw_addr); 00269 00270 /* bring the interface up */ 00271 netif_set_up(netif); 00272 00273 return ERR_OK; 00274 } 00275 00276 /** 00277 * Start AutoIP client 00278 * 00279 * @param netif network interface on which start the AutoIP client 00280 */ 00281 err_t 00282 autoip_start(struct netif *netif) 00283 { 00284 struct autoip *autoip = netif->autoip; 00285 err_t result = ERR_OK; 00286 00287 if(netif_is_up(netif)) { 00288 netif_set_down(netif); 00289 } 00290 00291 /* Set IP-Address, Netmask and Gateway to 0 to make sure that 00292 * ARP Packets are formed correctly 00293 */ 00294 ip_addr_set_zero(&netif->ip_addr); 00295 ip_addr_set_zero(&netif->netmask); 00296 ip_addr_set_zero(&netif->gw); 00297 00298 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00299 ("autoip_start(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], 00300 netif->name[1], (u16_t)netif->num)); 00301 if(autoip == NULL) { 00302 /* no AutoIP client attached yet? */ 00303 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, 00304 ("autoip_start(): starting new AUTOIP client\n")); 00305 autoip = (struct autoip *)mem_malloc(sizeof(struct autoip)); 00306 if(autoip == NULL) { 00307 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, 00308 ("autoip_start(): could not allocate autoip\n")); 00309 return ERR_MEM; 00310 } 00311 memset( autoip, 0, sizeof(struct autoip)); 00312 /* store this AutoIP client in the netif */ 00313 netif->autoip = autoip; 00314 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_start(): allocated autoip")); 00315 } else { 00316 autoip->state = AUTOIP_STATE_OFF; 00317 autoip->ttw = 0; 00318 autoip->sent_num = 0; 00319 memset(&autoip->llipaddr, 0, sizeof(ip_addr_t)); 00320 autoip->lastconflict = 0; 00321 } 00322 00323 autoip_create_addr(netif, &(autoip->llipaddr)); 00324 autoip->tried_llipaddr++; 00325 autoip_start_probing(netif); 00326 00327 return result; 00328 } 00329 00330 static void 00331 autoip_start_probing(struct netif *netif) 00332 { 00333 struct autoip *autoip = netif->autoip; 00334 00335 autoip->state = AUTOIP_STATE_PROBING; 00336 autoip->sent_num = 0; 00337 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00338 ("autoip_start_probing(): changing state to PROBING: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", 00339 ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr), 00340 ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr))); 00341 00342 /* time to wait to first probe, this is randomly 00343 * choosen out of 0 to PROBE_WAIT seconds. 00344 * compliant to RFC 3927 Section 2.2.1 00345 */ 00346 autoip->ttw = (u16_t)(LWIP_AUTOIP_RAND(netif) % (PROBE_WAIT * AUTOIP_TICKS_PER_SECOND)); 00347 00348 /* 00349 * if we tried more then MAX_CONFLICTS we must limit our rate for 00350 * accquiring and probing address 00351 * compliant to RFC 3927 Section 2.2.1 00352 */ 00353 if(autoip->tried_llipaddr > MAX_CONFLICTS) { 00354 autoip->ttw = RATE_LIMIT_INTERVAL * AUTOIP_TICKS_PER_SECOND; 00355 } 00356 } 00357 00358 /** 00359 * Handle a possible change in the network configuration. 00360 * 00361 * If there is an AutoIP address configured, take the interface down 00362 * and begin probing with the same address. 00363 */ 00364 void 00365 autoip_network_changed(struct netif *netif) 00366 { 00367 if (netif->autoip && netif->autoip->state != AUTOIP_STATE_OFF) { 00368 netif_set_down(netif); 00369 autoip_start_probing(netif); 00370 } 00371 } 00372 00373 /** 00374 * Stop AutoIP client 00375 * 00376 * @param netif network interface on which stop the AutoIP client 00377 */ 00378 err_t 00379 autoip_stop(struct netif *netif) 00380 { 00381 netif->autoip->state = AUTOIP_STATE_OFF; 00382 netif_set_down(netif); 00383 return ERR_OK; 00384 } 00385 00386 /** 00387 * Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds 00388 */ 00389 void 00390 autoip_tmr() 00391 { 00392 struct netif *netif = netif_list; 00393 /* loop through netif's */ 00394 while (netif != NULL) { 00395 /* only act on AutoIP configured interfaces */ 00396 if (netif->autoip != NULL) { 00397 if(netif->autoip->lastconflict > 0) { 00398 netif->autoip->lastconflict--; 00399 } 00400 00401 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, 00402 ("autoip_tmr() AutoIP-State: %"U16_F", ttw=%"U16_F"\n", 00403 (u16_t)(netif->autoip->state), netif->autoip->ttw)); 00404 00405 switch(netif->autoip->state) { 00406 case AUTOIP_STATE_PROBING: 00407 if(netif->autoip->ttw > 0) { 00408 netif->autoip->ttw--; 00409 } else { 00410 if(netif->autoip->sent_num >= PROBE_NUM) { 00411 netif->autoip->state = AUTOIP_STATE_ANNOUNCING; 00412 netif->autoip->sent_num = 0; 00413 netif->autoip->ttw = ANNOUNCE_WAIT * AUTOIP_TICKS_PER_SECOND; 00414 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00415 ("autoip_tmr(): changing state to ANNOUNCING: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", 00416 ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr), 00417 ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr))); 00418 } else { 00419 autoip_arp_probe(netif); 00420 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, 00421 ("autoip_tmr() PROBING Sent Probe\n")); 00422 netif->autoip->sent_num++; 00423 /* calculate time to wait to next probe */ 00424 netif->autoip->ttw = (u16_t)((LWIP_AUTOIP_RAND(netif) % 00425 ((PROBE_MAX - PROBE_MIN) * AUTOIP_TICKS_PER_SECOND) ) + 00426 PROBE_MIN * AUTOIP_TICKS_PER_SECOND); 00427 } 00428 } 00429 break; 00430 00431 case AUTOIP_STATE_ANNOUNCING: 00432 if(netif->autoip->ttw > 0) { 00433 netif->autoip->ttw--; 00434 } else { 00435 if(netif->autoip->sent_num == 0) { 00436 /* We are here the first time, so we waited ANNOUNCE_WAIT seconds 00437 * Now we can bind to an IP address and use it. 00438 * 00439 * autoip_bind calls netif_set_up. This triggers a gratuitous ARP 00440 * which counts as an announcement. 00441 */ 00442 autoip_bind(netif); 00443 } else { 00444 autoip_arp_announce(netif); 00445 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, 00446 ("autoip_tmr() ANNOUNCING Sent Announce\n")); 00447 } 00448 netif->autoip->ttw = ANNOUNCE_INTERVAL * AUTOIP_TICKS_PER_SECOND; 00449 netif->autoip->sent_num++; 00450 00451 if(netif->autoip->sent_num >= ANNOUNCE_NUM) { 00452 netif->autoip->state = AUTOIP_STATE_BOUND; 00453 netif->autoip->sent_num = 0; 00454 netif->autoip->ttw = 0; 00455 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, 00456 ("autoip_tmr(): changing state to BOUND: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", 00457 ip4_addr1_16(&netif->autoip->llipaddr), ip4_addr2_16(&netif->autoip->llipaddr), 00458 ip4_addr3_16(&netif->autoip->llipaddr), ip4_addr4_16(&netif->autoip->llipaddr))); 00459 } 00460 } 00461 break; 00462 } 00463 } 00464 /* proceed to next network interface */ 00465 netif = netif->next; 00466 } 00467 } 00468 00469 /** 00470 * Handles every incoming ARP Packet, called by etharp_arp_input. 00471 * 00472 * @param netif network interface to use for autoip processing 00473 * @param hdr Incoming ARP packet 00474 */ 00475 void 00476 autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr) 00477 { 00478 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE, ("autoip_arp_reply()\n")); 00479 if ((netif->autoip != NULL) && (netif->autoip->state != AUTOIP_STATE_OFF)) { 00480 /* when ip.src == llipaddr && hw.src != netif->hwaddr 00481 * 00482 * when probing ip.dst == llipaddr && hw.src != netif->hwaddr 00483 * we have a conflict and must solve it 00484 */ 00485 ip_addr_t sipaddr, dipaddr; 00486 struct eth_addr netifaddr; 00487 netifaddr.addr[0] = netif->hwaddr[0]; 00488 netifaddr.addr[1] = netif->hwaddr[1]; 00489 netifaddr.addr[2] = netif->hwaddr[2]; 00490 netifaddr.addr[3] = netif->hwaddr[3]; 00491 netifaddr.addr[4] = netif->hwaddr[4]; 00492 netifaddr.addr[5] = netif->hwaddr[5]; 00493 00494 /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without 00495 * structure packing (not using structure copy which breaks strict-aliasing rules). 00496 */ 00497 SMEMCPY(&sipaddr, &hdr->sipaddr, sizeof(sipaddr)); 00498 SMEMCPY(&dipaddr, &hdr->dipaddr, sizeof(dipaddr)); 00499 00500 if ((netif->autoip->state == AUTOIP_STATE_PROBING) || 00501 ((netif->autoip->state == AUTOIP_STATE_ANNOUNCING) && 00502 (netif->autoip->sent_num == 0))) { 00503 /* RFC 3927 Section 2.2.1: 00504 * from beginning to after ANNOUNCE_WAIT 00505 * seconds we have a conflict if 00506 * ip.src == llipaddr OR 00507 * ip.dst == llipaddr && hw.src != own hwaddr 00508 */ 00509 if ((ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr)) || 00510 (ip_addr_cmp(&dipaddr, &netif->autoip->llipaddr) && 00511 !eth_addr_cmp(&netifaddr, &hdr->shwaddr))) { 00512 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING, 00513 ("autoip_arp_reply(): Probe Conflict detected\n")); 00514 autoip_start(netif); 00515 } 00516 } else { 00517 /* RFC 3927 Section 2.5: 00518 * in any state we have a conflict if 00519 * ip.src == llipaddr && hw.src != own hwaddr 00520 */ 00521 if (ip_addr_cmp(&sipaddr, &netif->autoip->llipaddr) && 00522 !eth_addr_cmp(&netifaddr, &hdr->shwaddr)) { 00523 LWIP_DEBUGF(AUTOIP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | LWIP_DBG_LEVEL_WARNING, 00524 ("autoip_arp_reply(): Conflicting ARP-Packet detected\n")); 00525 autoip_handle_arp_conflict(netif); 00526 } 00527 } 00528 } 00529 } 00530 00531 #endif /* LWIP_AUTOIP */
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