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Example_RTOS
Rtos API example
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lwip_raw.c
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00001 /** 00002 * @file 00003 * Implementation of raw protocol PCBs for low-level handling of 00004 * different types of protocols besides (or overriding) those 00005 * already available in lwIP.\n 00006 * See also @ref raw_raw 00007 * 00008 * @defgroup raw_raw RAW 00009 * @ingroup callbackstyle_api 00010 * Implementation of raw protocol PCBs for low-level handling of 00011 * different types of protocols besides (or overriding) those 00012 * already available in lwIP.\n 00013 * @see @ref raw_api 00014 */ 00015 00016 /* 00017 * Copyright (c) 2001-2004 Swedish Institute of Computer Science. 00018 * All rights reserved. 00019 * 00020 * Redistribution and use in source and binary forms, with or without modification, 00021 * are permitted provided that the following conditions are met: 00022 * 00023 * 1. Redistributions of source code must retain the above copyright notice, 00024 * this list of conditions and the following disclaimer. 00025 * 2. Redistributions in binary form must reproduce the above copyright notice, 00026 * this list of conditions and the following disclaimer in the documentation 00027 * and/or other materials provided with the distribution. 00028 * 3. The name of the author may not be used to endorse or promote products 00029 * derived from this software without specific prior written permission. 00030 * 00031 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 00032 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 00033 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 00034 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 00035 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 00036 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 00037 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 00038 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 00039 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 00040 * OF SUCH DAMAGE. 00041 * 00042 * This file is part of the lwIP TCP/IP stack. 00043 * 00044 * Author: Adam Dunkels <adam@sics.se> 00045 * 00046 */ 00047 00048 #include "lwip/opt.h" 00049 00050 #if LWIP_RAW /* don't build if not configured for use in lwipopts.h */ 00051 00052 #include "lwip/def.h" 00053 #include "lwip/memp.h" 00054 #include "lwip/ip_addr.h" 00055 #include "lwip/netif.h" 00056 #include "lwip/raw.h" 00057 #include "lwip/stats.h" 00058 #include "lwip/ip6.h" 00059 #include "lwip/ip6_addr.h" 00060 #include "lwip/inet_chksum.h" 00061 00062 #include <string.h> 00063 00064 /** The list of RAW PCBs */ 00065 static struct raw_pcb *raw_pcbs; 00066 00067 static u8_t 00068 raw_input_match(struct raw_pcb *pcb, u8_t broadcast) 00069 { 00070 LWIP_UNUSED_ARG(broadcast); /* in IPv6 only case */ 00071 00072 #if LWIP_IPV4 && LWIP_IPV6 00073 /* Dual-stack: PCBs listening to any IP type also listen to any IP address */ 00074 if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) { 00075 #if IP_SOF_BROADCAST_RECV 00076 if ((broadcast != 0) && !ip_get_option(pcb, SOF_BROADCAST)) { 00077 return 0; 00078 } 00079 #endif /* IP_SOF_BROADCAST_RECV */ 00080 return 1; 00081 } 00082 #endif /* LWIP_IPV4 && LWIP_IPV6 */ 00083 00084 /* Only need to check PCB if incoming IP version matches PCB IP version */ 00085 if (IP_ADDR_PCB_VERSION_MATCH_EXACT(pcb, ip_current_dest_addr())) { 00086 #if LWIP_IPV4 00087 /* Special case: IPv4 broadcast: receive all broadcasts 00088 * Note: broadcast variable can only be 1 if it is an IPv4 broadcast */ 00089 if (broadcast != 0) { 00090 #if IP_SOF_BROADCAST_RECV 00091 if (ip_get_option(pcb, SOF_BROADCAST)) 00092 #endif /* IP_SOF_BROADCAST_RECV */ 00093 { 00094 if (ip4_addr_isany(ip_2_ip4(&pcb->local_ip))) { 00095 return 1; 00096 } 00097 } 00098 } else 00099 #endif /* LWIP_IPV4 */ 00100 /* Handle IPv4 and IPv6: catch all or exact match */ 00101 if (ip_addr_isany(&pcb->local_ip) || 00102 ip_addr_cmp(&pcb->local_ip, ip_current_dest_addr())) { 00103 return 1; 00104 } 00105 } 00106 00107 return 0; 00108 } 00109 00110 /** 00111 * Determine if in incoming IP packet is covered by a RAW PCB 00112 * and if so, pass it to a user-provided receive callback function. 00113 * 00114 * Given an incoming IP datagram (as a chain of pbufs) this function 00115 * finds a corresponding RAW PCB and calls the corresponding receive 00116 * callback function. 00117 * 00118 * @param p pbuf to be demultiplexed to a RAW PCB. 00119 * @param inp network interface on which the datagram was received. 00120 * @return - 1 if the packet has been eaten by a RAW PCB receive 00121 * callback function. The caller MAY NOT not reference the 00122 * packet any longer, and MAY NOT call pbuf_free(). 00123 * @return - 0 if packet is not eaten (pbuf is still referenced by the 00124 * caller). 00125 * 00126 */ 00127 u8_t 00128 raw_input(struct pbuf *p, struct netif *inp) 00129 { 00130 struct raw_pcb *pcb, *prev; 00131 s16_t proto; 00132 u8_t eaten = 0; 00133 u8_t broadcast = ip_addr_isbroadcast(ip_current_dest_addr(), ip_current_netif()); 00134 00135 LWIP_UNUSED_ARG(inp); 00136 00137 #if LWIP_IPV6 00138 #if LWIP_IPV4 00139 if (IP_HDR_GET_VERSION(p->payload) == 6) 00140 #endif /* LWIP_IPV4 */ 00141 { 00142 struct ip6_hdr *ip6hdr = (struct ip6_hdr *)p->payload; 00143 proto = IP6H_NEXTH(ip6hdr); 00144 } 00145 #if LWIP_IPV4 00146 else 00147 #endif /* LWIP_IPV4 */ 00148 #endif /* LWIP_IPV6 */ 00149 #if LWIP_IPV4 00150 { 00151 proto = IPH_PROTO((struct ip_hdr *)p->payload); 00152 } 00153 #endif /* LWIP_IPV4 */ 00154 00155 prev = NULL; 00156 pcb = raw_pcbs; 00157 /* loop through all raw pcbs until the packet is eaten by one */ 00158 /* this allows multiple pcbs to match against the packet by design */ 00159 while ((eaten == 0) && (pcb != NULL)) { 00160 if ((pcb->protocol == proto) && raw_input_match(pcb, broadcast)) { 00161 /* receive callback function available? */ 00162 if (pcb->recv != NULL) { 00163 #ifndef LWIP_NOASSERT 00164 void* old_payload = p->payload; 00165 #endif 00166 /* the receive callback function did not eat the packet? */ 00167 eaten = pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr()); 00168 if (eaten != 0) { 00169 /* receive function ate the packet */ 00170 p = NULL; 00171 eaten = 1; 00172 if (prev != NULL) { 00173 /* move the pcb to the front of raw_pcbs so that is 00174 found faster next time */ 00175 prev->next = pcb->next; 00176 pcb->next = raw_pcbs; 00177 raw_pcbs = pcb; 00178 } 00179 } else { 00180 /* sanity-check that the receive callback did not alter the pbuf */ 00181 LWIP_ASSERT("raw pcb recv callback altered pbuf payload pointer without eating packet", 00182 p->payload == old_payload); 00183 } 00184 } 00185 /* no receive callback function was set for this raw PCB */ 00186 } 00187 /* drop the packet */ 00188 prev = pcb; 00189 pcb = pcb->next; 00190 } 00191 return eaten; 00192 } 00193 00194 /** 00195 * @ingroup raw_raw 00196 * Bind a RAW PCB. 00197 * 00198 * @param pcb RAW PCB to be bound with a local address ipaddr. 00199 * @param ipaddr local IP address to bind with. Use IP4_ADDR_ANY to 00200 * bind to all local interfaces. 00201 * 00202 * @return lwIP error code. 00203 * - ERR_OK. Successful. No error occurred. 00204 * - ERR_USE. The specified IP address is already bound to by 00205 * another RAW PCB. 00206 * 00207 * @see raw_disconnect() 00208 */ 00209 err_t 00210 raw_bind(struct raw_pcb *pcb, const ip_addr_t *ipaddr) 00211 { 00212 if ((pcb == NULL) || (ipaddr == NULL)) { 00213 return ERR_VAL; 00214 } 00215 ip_addr_set_ipaddr(&pcb->local_ip, ipaddr); 00216 return ERR_OK; 00217 } 00218 00219 /** 00220 * @ingroup raw_raw 00221 * Connect an RAW PCB. This function is required by upper layers 00222 * of lwip. Using the raw api you could use raw_sendto() instead 00223 * 00224 * This will associate the RAW PCB with the remote address. 00225 * 00226 * @param pcb RAW PCB to be connected with remote address ipaddr and port. 00227 * @param ipaddr remote IP address to connect with. 00228 * 00229 * @return lwIP error code 00230 * 00231 * @see raw_disconnect() and raw_sendto() 00232 */ 00233 err_t 00234 raw_connect(struct raw_pcb *pcb, const ip_addr_t *ipaddr) 00235 { 00236 if ((pcb == NULL) || (ipaddr == NULL)) { 00237 return ERR_VAL; 00238 } 00239 ip_addr_set_ipaddr(&pcb->remote_ip, ipaddr); 00240 return ERR_OK; 00241 } 00242 00243 /** 00244 * @ingroup raw_raw 00245 * Set the callback function for received packets that match the 00246 * raw PCB's protocol and binding. 00247 * 00248 * The callback function MUST either 00249 * - eat the packet by calling pbuf_free() and returning non-zero. The 00250 * packet will not be passed to other raw PCBs or other protocol layers. 00251 * - not free the packet, and return zero. The packet will be matched 00252 * against further PCBs and/or forwarded to another protocol layers. 00253 */ 00254 void 00255 raw_recv(struct raw_pcb *pcb, raw_recv_fn recv, void *recv_arg) 00256 { 00257 /* remember recv() callback and user data */ 00258 pcb->recv = recv; 00259 pcb->recv_arg = recv_arg; 00260 } 00261 00262 /** 00263 * @ingroup raw_raw 00264 * Send the raw IP packet to the given address. Note that actually you cannot 00265 * modify the IP headers (this is inconsistent with the receive callback where 00266 * you actually get the IP headers), you can only specify the IP payload here. 00267 * It requires some more changes in lwIP. (there will be a raw_send() function 00268 * then.) 00269 * 00270 * @param pcb the raw pcb which to send 00271 * @param p the IP payload to send 00272 * @param ipaddr the destination address of the IP packet 00273 * 00274 */ 00275 err_t 00276 raw_sendto(struct raw_pcb *pcb, struct pbuf *p, const ip_addr_t *ipaddr) 00277 { 00278 err_t err; 00279 struct netif *netif; 00280 const ip_addr_t *src_ip; 00281 struct pbuf *q; /* q will be sent down the stack */ 00282 s16_t header_size; 00283 00284 if ((pcb == NULL) || (ipaddr == NULL) || !IP_ADDR_PCB_VERSION_MATCH(pcb, ipaddr)) { 00285 return ERR_VAL; 00286 } 00287 00288 LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_sendto\n")); 00289 00290 header_size = ( 00291 #if LWIP_IPV4 && LWIP_IPV6 00292 IP_IS_V6(ipaddr) ? IP6_HLEN : IP_HLEN); 00293 #elif LWIP_IPV4 00294 IP_HLEN); 00295 #else 00296 IP6_HLEN); 00297 #endif 00298 00299 /* not enough space to add an IP header to first pbuf in given p chain? */ 00300 if (pbuf_header(p, header_size)) { 00301 /* allocate header in new pbuf */ 00302 q = pbuf_alloc(PBUF_IP, 0, PBUF_RAM); 00303 /* new header pbuf could not be allocated? */ 00304 if (q == NULL) { 00305 LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("raw_sendto: could not allocate header\n")); 00306 return ERR_MEM; 00307 } 00308 if (p->tot_len != 0) { 00309 /* chain header q in front of given pbuf p */ 00310 pbuf_chain(q, p); 00311 } 00312 /* { first pbuf q points to header pbuf } */ 00313 LWIP_DEBUGF(RAW_DEBUG, ("raw_sendto: added header pbuf %p before given pbuf %p\n", (void *)q, (void *)p)); 00314 } else { 00315 /* first pbuf q equals given pbuf */ 00316 q = p; 00317 if (pbuf_header(q, -header_size)) { 00318 LWIP_ASSERT("Can't restore header we just removed!", 0); 00319 return ERR_MEM; 00320 } 00321 } 00322 00323 if(IP_IS_ANY_TYPE_VAL(pcb->local_ip)) { 00324 /* Don't call ip_route() with IP_ANY_TYPE */ 00325 netif = ip_route(IP46_ADDR_ANY(IP_GET_TYPE(ipaddr)), ipaddr); 00326 } else { 00327 netif = ip_route(&pcb->local_ip, ipaddr); 00328 } 00329 00330 if (netif == NULL) { 00331 LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: No route to ")); 00332 ip_addr_debug_print(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ipaddr); 00333 /* free any temporary header pbuf allocated by pbuf_header() */ 00334 if (q != p) { 00335 pbuf_free(q); 00336 } 00337 return ERR_RTE; 00338 } 00339 00340 #if IP_SOF_BROADCAST 00341 if (IP_IS_V4(ipaddr)) 00342 { 00343 /* broadcast filter? */ 00344 if (!ip_get_option(pcb, SOF_BROADCAST) && ip_addr_isbroadcast(ipaddr, netif)) { 00345 LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: SOF_BROADCAST not enabled on pcb %p\n", (void *)pcb)); 00346 /* free any temporary header pbuf allocated by pbuf_header() */ 00347 if (q != p) { 00348 pbuf_free(q); 00349 } 00350 return ERR_VAL; 00351 } 00352 } 00353 #endif /* IP_SOF_BROADCAST */ 00354 00355 if (ip_addr_isany(&pcb->local_ip)) { 00356 /* use outgoing network interface IP address as source address */ 00357 src_ip = ip_netif_get_local_ip(netif, ipaddr); 00358 #if LWIP_IPV6 00359 if (src_ip == NULL) { 00360 if (q != p) { 00361 pbuf_free(q); 00362 } 00363 return ERR_RTE; 00364 } 00365 #endif /* LWIP_IPV6 */ 00366 } else { 00367 /* use RAW PCB local IP address as source address */ 00368 src_ip = &pcb->local_ip; 00369 } 00370 00371 #if LWIP_IPV6 00372 /* If requested, based on the IPV6_CHECKSUM socket option per RFC3542, 00373 compute the checksum and update the checksum in the payload. */ 00374 if (IP_IS_V6(ipaddr) && pcb->chksum_reqd) { 00375 u16_t chksum = ip6_chksum_pseudo(p, pcb->protocol, p->tot_len, ip_2_ip6(src_ip), ip_2_ip6(ipaddr)); 00376 LWIP_ASSERT("Checksum must fit into first pbuf", p->len >= (pcb->chksum_offset + 2)); 00377 SMEMCPY(((u8_t *)p->payload) + pcb->chksum_offset, &chksum, sizeof(u16_t)); 00378 } 00379 #endif 00380 00381 NETIF_SET_HWADDRHINT(netif, &pcb->addr_hint); 00382 err = ip_output_if(q, src_ip, ipaddr, pcb->ttl, pcb->tos, pcb->protocol, netif); 00383 NETIF_SET_HWADDRHINT(netif, NULL); 00384 00385 /* did we chain a header earlier? */ 00386 if (q != p) { 00387 /* free the header */ 00388 pbuf_free(q); 00389 } 00390 return err; 00391 } 00392 00393 /** 00394 * @ingroup raw_raw 00395 * Send the raw IP packet to the address given by raw_connect() 00396 * 00397 * @param pcb the raw pcb which to send 00398 * @param p the IP payload to send 00399 * 00400 */ 00401 err_t 00402 raw_send(struct raw_pcb *pcb, struct pbuf *p) 00403 { 00404 return raw_sendto(pcb, p, &pcb->remote_ip); 00405 } 00406 00407 /** 00408 * @ingroup raw_raw 00409 * Remove an RAW PCB. 00410 * 00411 * @param pcb RAW PCB to be removed. The PCB is removed from the list of 00412 * RAW PCB's and the data structure is freed from memory. 00413 * 00414 * @see raw_new() 00415 */ 00416 void 00417 raw_remove(struct raw_pcb *pcb) 00418 { 00419 struct raw_pcb *pcb2; 00420 /* pcb to be removed is first in list? */ 00421 if (raw_pcbs == pcb) { 00422 /* make list start at 2nd pcb */ 00423 raw_pcbs = raw_pcbs->next; 00424 /* pcb not 1st in list */ 00425 } else { 00426 for (pcb2 = raw_pcbs; pcb2 != NULL; pcb2 = pcb2->next) { 00427 /* find pcb in raw_pcbs list */ 00428 if (pcb2->next != NULL && pcb2->next == pcb) { 00429 /* remove pcb from list */ 00430 pcb2->next = pcb->next; 00431 break; 00432 } 00433 } 00434 } 00435 memp_free(MEMP_RAW_PCB, pcb); 00436 } 00437 00438 /** 00439 * @ingroup raw_raw 00440 * Create a RAW PCB. 00441 * 00442 * @return The RAW PCB which was created. NULL if the PCB data structure 00443 * could not be allocated. 00444 * 00445 * @param proto the protocol number of the IPs payload (e.g. IP_PROTO_ICMP) 00446 * 00447 * @see raw_remove() 00448 */ 00449 struct raw_pcb * 00450 raw_new(u8_t proto) 00451 { 00452 struct raw_pcb *pcb; 00453 00454 LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_new\n")); 00455 00456 pcb = (struct raw_pcb *)memp_malloc(MEMP_RAW_PCB); 00457 /* could allocate RAW PCB? */ 00458 if (pcb != NULL) { 00459 /* initialize PCB to all zeroes */ 00460 memset(pcb, 0, sizeof(struct raw_pcb)); 00461 pcb->protocol = proto; 00462 pcb->ttl = RAW_TTL; 00463 pcb->next = raw_pcbs; 00464 raw_pcbs = pcb; 00465 } 00466 return pcb; 00467 } 00468 00469 /** 00470 * @ingroup raw_raw 00471 * Create a RAW PCB for specific IP type. 00472 * 00473 * @return The RAW PCB which was created. NULL if the PCB data structure 00474 * could not be allocated. 00475 * 00476 * @param type IP address type, see @ref lwip_ip_addr_type definitions. 00477 * If you want to listen to IPv4 and IPv6 (dual-stack) packets, 00478 * supply @ref IPADDR_TYPE_ANY as argument and bind to @ref IP_ANY_TYPE. 00479 * @param proto the protocol number (next header) of the IPv6 packet payload 00480 * (e.g. IP6_NEXTH_ICMP6) 00481 * 00482 * @see raw_remove() 00483 */ 00484 struct raw_pcb * 00485 raw_new_ip_type(u8_t type, u8_t proto) 00486 { 00487 struct raw_pcb *pcb; 00488 pcb = raw_new(proto); 00489 #if LWIP_IPV4 && LWIP_IPV6 00490 if (pcb != NULL) { 00491 IP_SET_TYPE_VAL(pcb->local_ip, type); 00492 IP_SET_TYPE_VAL(pcb->remote_ip, type); 00493 } 00494 #else /* LWIP_IPV4 && LWIP_IPV6 */ 00495 LWIP_UNUSED_ARG(type); 00496 #endif /* LWIP_IPV4 && LWIP_IPV6 */ 00497 return pcb; 00498 } 00499 00500 /** This function is called from netif.c when address is changed 00501 * 00502 * @param old_addr IP address of the netif before change 00503 * @param new_addr IP address of the netif after change 00504 */ 00505 void raw_netif_ip_addr_changed(const ip_addr_t* old_addr, const ip_addr_t* new_addr) 00506 { 00507 struct raw_pcb* rpcb; 00508 00509 if (!ip_addr_isany(old_addr) && !ip_addr_isany(new_addr)) { 00510 for (rpcb = raw_pcbs; rpcb != NULL; rpcb = rpcb->next) { 00511 /* PCB bound to current local interface address? */ 00512 if (ip_addr_cmp(&rpcb->local_ip, old_addr)) { 00513 /* The PCB is bound to the old ipaddr and 00514 * is set to bound to the new one instead */ 00515 ip_addr_copy(rpcb->local_ip, *new_addr); 00516 } 00517 } 00518 } 00519 } 00520 00521 #endif /* LWIP_RAW */
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