minix/lib/liblwip/dist/src/core/raw.c

   1 /**
   2  * @file
   3  * Implementation of raw protocol PCBs for low-level handling of
   4  * different types of protocols besides (or overriding) those
   5  * already available in lwIP.\n
   6  * See also @ref raw_raw
   7  *
   8  * @defgroup raw_raw RAW
   9  * @ingroup callbackstyle_api
  10  * Implementation of raw protocol PCBs for low-level handling of
  11  * different types of protocols besides (or overriding) those
  12  * already available in lwIP.\n
  13  * @see @ref raw_api
  14  */
  15
  16 /*
  17  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
  18  * All rights reserved.
  19  *
  20  * Redistribution and use in source and binary forms, with or without modification,
  21  * are permitted provided that the following conditions are met:
  22  *
  23  * 1. Redistributions of source code must retain the above copyright notice,
  24  *    this list of conditions and the following disclaimer.
  25  * 2. Redistributions in binary form must reproduce the above copyright notice,
  26  *    this list of conditions and the following disclaimer in the documentation
  27  *    and/or other materials provided with the distribution.
  28  * 3. The name of the author may not be used to endorse or promote products
  29  *    derived from this software without specific prior written permission.
  30  *
  31  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  32  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  33  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  34  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  35  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  36  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  37  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  38  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  39  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  40  * OF SUCH DAMAGE.
  41  *
  42  * This file is part of the lwIP TCP/IP stack.
  43  *
  44  * Author: Adam Dunkels <adam@sics.se>
  45  *
  46  */
  47
  48 #include "lwip/opt.h"
  49
  50 #if LWIP_RAW /* don't build if not configured for use in lwipopts.h */
  51
  52 #include "lwip/def.h"
  53 #include "lwip/memp.h"
  54 #include "lwip/ip_addr.h"
  55 #include "lwip/netif.h"
  56 #include "lwip/raw.h"
  57 #include "lwip/stats.h"
  58 #include "lwip/ip6.h"
  59 #include "lwip/ip6_addr.h"
  60 #include "lwip/inet_chksum.h"
  61
  62 #include <string.h>
  63
  64 /** The list of RAW PCBs */
  65 static struct raw_pcb *raw_pcbs;
  66
  67 static u8_t
  68 raw_input_local_match(struct raw_pcb *pcb, u8_t broadcast)
  69 {
  70   LWIP_UNUSED_ARG(broadcast); /* in IPv6 only case */
  71
  72 #if LWIP_IPV4 && LWIP_IPV6
  73   /* Dual-stack: PCBs listening to any IP type also listen to any IP address */
  74   if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) {
  75 #if IP_SOF_BROADCAST_RECV
  76     if ((broadcast != 0) && !ip_get_option(pcb, SOF_BROADCAST)) {
  77       return 0;
  78     }
  79 #endif /* IP_SOF_BROADCAST_RECV */
  80     return 1;
  81   }
  82 #endif /* LWIP_IPV4 && LWIP_IPV6 */
  83
  84   /* Only need to check PCB if incoming IP version matches PCB IP version */
  85   if (IP_ADDR_PCB_VERSION_MATCH_EXACT(pcb, ip_current_dest_addr())) {
  86 #if LWIP_IPV4
  87     /* Special case: IPv4 broadcast: receive all broadcasts
  88      * Note: broadcast variable can only be 1 if it is an IPv4 broadcast */
  89     if (broadcast != 0) {
  90 #if IP_SOF_BROADCAST_RECV
  91       if (ip_get_option(pcb, SOF_BROADCAST))
  92 #endif /* IP_SOF_BROADCAST_RECV */
  93       {
  94         if (ip4_addr_isany(ip_2_ip4(&pcb->local_ip))) {
  95           return 1;
  96         }
  97       }
  98     } else
  99 #endif /* LWIP_IPV4 */
 100     /* Handle IPv4 and IPv6: catch all or exact match */
 101     if (ip_addr_isany(&pcb->local_ip) ||
 102        ip_addr_cmp(&pcb->local_ip, ip_current_dest_addr())) {
 103       return 1;
 104     }
 105   }
 106
 107   return 0;
 108 }
 109
 110 /**
 111  * Determine if in incoming IP packet is covered by a RAW PCB
 112  * and if so, pass it to a user-provided receive callback function.
 113  *
 114  * Given an incoming IP datagram (as a chain of pbufs) this function
 115  * finds a corresponding RAW PCB and calls the corresponding receive
 116  * callback function.
 117  *
 118  * @param p pbuf to be demultiplexed to a RAW PCB.
 119  * @param inp network interface on which the datagram was received.
 120  * @return - 1 if the packet has been eaten by a RAW PCB receive
 121  *           callback function. The caller MAY NOT not reference the
 122  *           packet any longer, and MAY NOT call pbuf_free().
 123  * @return - 0 if packet is not eaten (pbuf is still referenced by the
 124  *           caller).
 125  *
 126  */
 127 u8_t
 128 raw_input(struct pbuf *p, struct netif *inp)
 129 {
 130   struct raw_pcb *pcb, *prev;
 131   s16_t proto;
 132   u8_t eaten = 0;
 133   u8_t broadcast = ip_addr_isbroadcast(ip_current_dest_addr(), ip_current_netif());
 134
 135   LWIP_UNUSED_ARG(inp);
 136
 137 #if LWIP_IPV6
 138 #if LWIP_IPV4
 139   if (IP_HDR_GET_VERSION(p->payload) == 6)
 140 #endif /* LWIP_IPV4 */
 141   {
 142     struct ip6_hdr *ip6hdr = (struct ip6_hdr *)p->payload;
 143     proto = IP6H_NEXTH(ip6hdr);
 144   }
 145 #if LWIP_IPV4
 146   else
 147 #endif /* LWIP_IPV4 */
 148 #endif /* LWIP_IPV6 */
 149 #if LWIP_IPV4
 150   {
 151     proto = IPH_PROTO((struct ip_hdr *)p->payload);
 152   }
 153 #endif /* LWIP_IPV4 */
 154
 155   prev = NULL;
 156   pcb = raw_pcbs;
 157   /* loop through all raw pcbs until the packet is eaten by one */
 158   /* this allows multiple pcbs to match against the packet by design */
 159   while ((eaten == 0) && (pcb != NULL)) {
 160     if ((pcb->protocol == proto) && raw_input_local_match(pcb, broadcast) &&
 161         (((pcb->flags & RAW_FLAGS_CONNECTED) == 0) ||
 162         ip_addr_cmp(&pcb->remote_ip, ip_current_src_addr()))) {
 163       /* receive callback function available? */
 164       if (pcb->recv != NULL) {
 165 #ifndef LWIP_NOASSERT
 166         void* old_payload = p->payload;
 167 #endif
 168         /* the receive callback function did not eat the packet? */
 169         eaten = pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr());
 170         if (eaten != 0) {
 171           /* receive function ate the packet */
 172           p = NULL;
 173           eaten = 1;
 174           if (prev != NULL) {
 175           /* move the pcb to the front of raw_pcbs so that is
 176              found faster next time */
 177             prev->next = pcb->next;
 178             pcb->next = raw_pcbs;
 179             raw_pcbs = pcb;
 180           }
 181         } else {
 182           /* sanity-check that the receive callback did not alter the pbuf */
 183           LWIP_ASSERT("raw pcb recv callback altered pbuf payload pointer without eating packet",
 184             p->payload == old_payload);
 185         }
 186       }
 187       /* no receive callback function was set for this raw PCB */
 188     }
 189     /* drop the packet */
 190     prev = pcb;
 191     pcb = pcb->next;
 192   }
 193   return eaten;
 194 }
 195
 196 /**
 197  * @ingroup raw_raw
 198  * Bind a RAW PCB.
 199  *
 200  * @param pcb RAW PCB to be bound with a local address ipaddr.
 201  * @param ipaddr local IP address to bind with. Use IP4_ADDR_ANY to
 202  * bind to all local interfaces.
 203  *
 204  * @return lwIP error code.
 205  * - ERR_OK. Successful. No error occurred.
 206  * - ERR_USE. The specified IP address is already bound to by
 207  * another RAW PCB.
 208  *
 209  * @see raw_disconnect()
 210  */
 211 err_t
 212 raw_bind(struct raw_pcb *pcb, const ip_addr_t *ipaddr)
 213 {
 214   if ((pcb == NULL) || (ipaddr == NULL)) {
 215     return ERR_VAL;
 216   }
 217   ip_addr_set_ipaddr(&pcb->local_ip, ipaddr);
 218 #if LWIP_IPV6 && LWIP_IPV6_SCOPES
 219   /* If the given IP address should have a zone but doesn't, assign one now.
 220    * This is legacy support: scope-aware callers should always provide properly
 221    * zoned source addresses. */
 222   if (IP_IS_V6(&pcb->local_ip) &&
 223       ip6_addr_lacks_zone(ip_2_ip6(&pcb->local_ip), IP6_UNKNOWN)) {
 224     ip6_addr_select_zone(ip_2_ip6(&pcb->local_ip), ip_2_ip6(&pcb->local_ip));
 225   }
 226 #endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */
 227   return ERR_OK;
 228 }
 229
 230 /**
 231  * @ingroup raw_raw
 232  * Connect an RAW PCB. This function is required by upper layers
 233  * of lwip. Using the raw api you could use raw_sendto() instead
 234  *
 235  * This will associate the RAW PCB with the remote address.
 236  *
 237  * @param pcb RAW PCB to be connected with remote address ipaddr and port.
 238  * @param ipaddr remote IP address to connect with.
 239  *
 240  * @return lwIP error code
 241  *
 242  * @see raw_disconnect() and raw_sendto()
 243  */
 244 err_t
 245 raw_connect(struct raw_pcb *pcb, const ip_addr_t *ipaddr)
 246 {
 247   if ((pcb == NULL) || (ipaddr == NULL)) {
 248     return ERR_VAL;
 249   }
 250   ip_addr_set_ipaddr(&pcb->remote_ip, ipaddr);
 251 #if LWIP_IPV6 && LWIP_IPV6_SCOPES
 252   /* If the given IP address should have a zone but doesn't, assign one now,
 253    * using the bound address to make a more informed decision when possible. */
 254   if (IP_IS_V6(&pcb->remote_ip) &&
 255       ip6_addr_lacks_zone(ip_2_ip6(&pcb->remote_ip), IP6_UNKNOWN)) {
 256     ip6_addr_select_zone(ip_2_ip6(&pcb->remote_ip), ip_2_ip6(&pcb->local_ip));
 257   }
 258 #endif /* LWIP_IPV6 && LWIP_IPV6_SCOPES */
 259   pcb->flags |= RAW_FLAGS_CONNECTED;
 260   return ERR_OK;
 261 }
 262
 263 /**
 264  * @ingroup raw_raw
 265  * Disconnect a RAW PCB.
 266  *
 267  * @param pcb the raw pcb to disconnect.
 268  */
 269 void
 270 raw_disconnect(struct raw_pcb *pcb)
 271 {
 272   /* reset remote address association */
 273 #if LWIP_IPV4 && LWIP_IPV6
 274   if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) {
 275     ip_addr_copy(pcb->remote_ip, *IP_ANY_TYPE);
 276   } else {
 277 #endif
 278     ip_addr_set_any(IP_IS_V6_VAL(pcb->remote_ip), &pcb->remote_ip);
 279 #if LWIP_IPV4 && LWIP_IPV6
 280   }
 281 #endif
 282   /* mark PCB as unconnected */
 283   pcb->flags &= ~RAW_FLAGS_CONNECTED;
 284 }
 285
 286 /**
 287  * @ingroup raw_raw
 288  * Set the callback function for received packets that match the
 289  * raw PCB's protocol and binding.
 290  *
 291  * The callback function MUST either
 292  * - eat the packet by calling pbuf_free() and returning non-zero. The
 293  *   packet will not be passed to other raw PCBs or other protocol layers.
 294  * - not free the packet, and return zero. The packet will be matched
 295  *   against further PCBs and/or forwarded to another protocol layers.
 296  */
 297 void
 298 raw_recv(struct raw_pcb *pcb, raw_recv_fn recv, void *recv_arg)
 299 {
 300   /* remember recv() callback and user data */
 301   pcb->recv = recv;
 302   pcb->recv_arg = recv_arg;
 303 }
 304
 305 /**
 306  * @ingroup raw_raw
 307  * Send the raw IP packet to the given address. An IP header will be prepended
 308  * to the packet, unless the RAW_FLAGS_HDRINCL flag is set on the PCB. In that
 309  * case, the packet must include an IP header, which will then be sent as is.
 310  *
 311  * @param pcb the raw pcb which to send
 312  * @param p the IP payload to send
 313  * @param ipaddr the destination address of the IP packet
 314  *
 315  */
 316 err_t
 317 raw_sendto(struct raw_pcb *pcb, struct pbuf *p, const ip_addr_t *ipaddr)
 318 {
 319   struct netif *netif;
 320   const ip_addr_t *src_ip;
 321
 322   if ((pcb == NULL) || (ipaddr == NULL) || !IP_ADDR_PCB_VERSION_MATCH(pcb, ipaddr)) {
 323     return ERR_VAL;
 324   }
 325
 326   LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_sendto\n"));
 327
 328 #if LWIP_MULTICAST_TX_OPTIONS
 329   netif = NULL;
 330   if (ip_addr_ismulticast(ipaddr)) {
 331     /* For multicast-destined packets, use the user-provided interface index to
 332      * determine the outgoing interface, if an interface index is set and a
 333      * matching netif can be found. Otherwise, fall back to regular routing. */
 334     netif = netif_get_by_index(pcb->mcast_ifindex);
 335   }
 336
 337   if (netif == NULL)
 338 #endif /* LWIP_MULTICAST_TX_OPTIONS */
 339   {
 340     if (IP_IS_ANY_TYPE_VAL(pcb->local_ip)) {
 341       /* Don't call ip_route() with IP_ANY_TYPE */
 342       netif = ip_route(IP46_ADDR_ANY(IP_GET_TYPE(ipaddr)), ipaddr);
 343     } else {
 344       netif = ip_route(&pcb->local_ip, ipaddr);
 345     }
 346   }
 347
 348   if (netif == NULL) {
 349     LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: No route to "));
 350     ip_addr_debug_print(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ipaddr);
 351     return ERR_RTE;
 352   }
 353
 354   if (ip_addr_isany(&pcb->local_ip) || ip_addr_ismulticast(&pcb->local_ip)) {
 355     /* use outgoing network interface IP address as source address */
 356     src_ip = ip_netif_get_local_ip(netif, ipaddr);
 357 #if LWIP_IPV6
 358     if (src_ip == NULL) {
 359       return ERR_RTE;
 360     }
 361 #endif /* LWIP_IPV6 */
 362   } else {
 363     /* use RAW PCB local IP address as source address */
 364     src_ip = &pcb->local_ip;
 365   }
 366
 367   return raw_sendto_if_src(pcb, p, ipaddr, netif, src_ip);
 368 }
 369
 370 /**
 371  * @ingroup raw_raw
 372  * Send the raw IP packet to the given address, using a particular outgoing
 373  * netif and source IP address. An IP header will be prepended to the packet,
 374  * unless the RAW_FLAGS_HDRINCL flag is set on the PCB. In that case, the
 375  * packet must include an IP header, which will then be sent as is.
 376  *
 377  * @param pcb RAW PCB used to send the data
 378  * @param p chain of pbufs to be sent
 379  * @param dst_ip destination IP address
 380  * @param netif the netif used for sending
 381  * @param src_ip source IP address
 382  */
 383 err_t
 384 raw_sendto_if_src(struct raw_pcb *pcb, struct pbuf *p, const ip_addr_t *dst_ip,
 385     struct netif *netif, const ip_addr_t *src_ip)
 386 {
 387   err_t err;
 388   struct pbuf *q; /* q will be sent down the stack */
 389   s16_t header_size;
 390   u8_t ttl;
 391
 392   if ((pcb == NULL) || (dst_ip == NULL) || (netif == NULL) || (src_ip == NULL) ||
 393       !IP_ADDR_PCB_VERSION_MATCH(pcb, src_ip) || !IP_ADDR_PCB_VERSION_MATCH(pcb, dst_ip)) {
 394     return ERR_VAL;
 395   }
 396
 397   header_size = (
 398 #if LWIP_IPV4 && LWIP_IPV6
 399     IP_IS_V6(dst_ip) ? IP6_HLEN : IP_HLEN);
 400 #elif LWIP_IPV4
 401     IP_HLEN);
 402 #else
 403     IP6_HLEN);
 404 #endif
 405
 406   /* Handle the HDRINCL option as an exception: none of the code below applies
 407    * to this case, and sending the packet needs to be done differently too. */
 408   if (pcb->flags & RAW_FLAGS_HDRINCL) {
 409     /* A full header *must* be present in the first pbuf of the chain, as the
 410      * output routines may access its fields directly. */
 411     if (p->len < header_size) {
 412       return ERR_VAL;
 413     }
 414     /* @todo multicast loop support, if at all desired for this scenario.. */
 415     NETIF_SET_HWADDRHINT(netif, &pcb->addr_hint);
 416     err = ip_output_if_hdrincl(p, src_ip, dst_ip, netif);
 417     NETIF_SET_HWADDRHINT(netif, NULL);
 418     return err;
 419   }
 420
 421   /* packet too large to add an IP header without causing an overflow? */
 422   if ((u16_t)(p->tot_len + header_size) < p->tot_len) {
 423     return ERR_MEM;
 424   }
 425   /* not enough space to add an IP header to first pbuf in given p chain? */
 426   if (pbuf_header(p, header_size)) {
 427     /* allocate header in new pbuf */
 428     q = pbuf_alloc(PBUF_IP, 0, PBUF_RAM);
 429     /* new header pbuf could not be allocated? */
 430     if (q == NULL) {
 431       LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, ("raw_sendto: could not allocate header\n"));
 432       return ERR_MEM;
 433     }
 434     if (p->tot_len != 0) {
 435       /* chain header q in front of given pbuf p */
 436       pbuf_chain(q, p);
 437     }
 438     /* { first pbuf q points to header pbuf } */
 439     LWIP_DEBUGF(RAW_DEBUG, ("raw_sendto: added header pbuf %p before given pbuf %p\n", (void *)q, (void *)p));
 440   } else {
 441     /* first pbuf q equals given pbuf */
 442     q = p;
 443     if (pbuf_header(q, -header_size)) {
 444       LWIP_ASSERT("Can't restore header we just removed!", 0);
 445       return ERR_MEM;
 446     }
 447   }
 448
 449 #if IP_SOF_BROADCAST
 450   if (IP_IS_V4(dst_ip))
 451   {
 452     /* broadcast filter? */
 453     if (!ip_get_option(pcb, SOF_BROADCAST) && ip_addr_isbroadcast(dst_ip, netif)) {
 454       LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_LEVEL_WARNING, ("raw_sendto: SOF_BROADCAST not enabled on pcb %p\n", (void *)pcb));
 455       /* free any temporary header pbuf allocated by pbuf_header() */
 456       if (q != p) {
 457         pbuf_free(q);
 458       }
 459       return ERR_VAL;
 460     }
 461   }
 462 #endif /* IP_SOF_BROADCAST */
 463
 464   /* Multicast Loop? */
 465 #if LWIP_MULTICAST_TX_OPTIONS
 466   if (((pcb->flags & RAW_FLAGS_MULTICAST_LOOP) != 0) && ip_addr_ismulticast(dst_ip)) {
 467     q->flags |= PBUF_FLAG_MCASTLOOP;
 468   }
 469 #endif /* LWIP_MULTICAST_TX_OPTIONS */
 470
 471 #if LWIP_IPV6
 472   /* If requested, based on the IPV6_CHECKSUM socket option per RFC3542,
 473      compute the checksum and update the checksum in the payload. */
 474   if (IP_IS_V6(dst_ip) && pcb->chksum_reqd) {
 475     u16_t chksum = ip6_chksum_pseudo(p, pcb->protocol, p->tot_len, ip_2_ip6(src_ip), ip_2_ip6(dst_ip));
 476     LWIP_ASSERT("Checksum must fit into first pbuf", p->len >= (pcb->chksum_offset + 2));
 477     SMEMCPY(((u8_t *)p->payload) + pcb->chksum_offset, &chksum, sizeof(u16_t));
 478   }
 479 #endif
 480
 481   /* Determine TTL to use */
 482 #if LWIP_MULTICAST_TX_OPTIONS
 483   ttl = (ip_addr_ismulticast(dst_ip) ? raw_get_multicast_ttl(pcb) : pcb->ttl);
 484 #else /* LWIP_MULTICAST_TX_OPTIONS */
 485   ttl = pcb->ttl;
 486 #endif /* LWIP_MULTICAST_TX_OPTIONS */
 487
 488   NETIF_SET_HWADDRHINT(netif, &pcb->addr_hint);
 489   err = ip_output_if(q, src_ip, dst_ip, ttl, pcb->tos, pcb->protocol, netif);
 490   NETIF_SET_HWADDRHINT(netif, NULL);
 491
 492   /* did we chain a header earlier? */
 493   if (q != p) {
 494     /* free the header */
 495     pbuf_free(q);
 496   }
 497   return err;
 498 }
 499
 500 /**
 501  * @ingroup raw_raw
 502  * Send the raw IP packet to the address given by raw_connect()
 503  *
 504  * @param pcb the raw pcb which to send
 505  * @param p the IP payload to send
 506  *
 507  */
 508 err_t
 509 raw_send(struct raw_pcb *pcb, struct pbuf *p)
 510 {
 511   return raw_sendto(pcb, p, &pcb->remote_ip);
 512 }
 513
 514 /**
 515  * @ingroup raw_raw
 516  * Remove an RAW PCB.
 517  *
 518  * @param pcb RAW PCB to be removed. The PCB is removed from the list of
 519  * RAW PCB's and the data structure is freed from memory.
 520  *
 521  * @see raw_new()
 522  */
 523 void
 524 raw_remove(struct raw_pcb *pcb)
 525 {
 526   struct raw_pcb *pcb2;
 527   /* pcb to be removed is first in list? */
 528   if (raw_pcbs == pcb) {
 529     /* make list start at 2nd pcb */
 530     raw_pcbs = raw_pcbs->next;
 531     /* pcb not 1st in list */
 532   } else {
 533     for (pcb2 = raw_pcbs; pcb2 != NULL; pcb2 = pcb2->next) {
 534       /* find pcb in raw_pcbs list */
 535       if (pcb2->next != NULL && pcb2->next == pcb) {
 536         /* remove pcb from list */
 537         pcb2->next = pcb->next;
 538         break;
 539       }
 540     }
 541   }
 542   memp_free(MEMP_RAW_PCB, pcb);
 543 }
 544
 545 /**
 546  * @ingroup raw_raw
 547  * Create a RAW PCB.
 548  *
 549  * @return The RAW PCB which was created. NULL if the PCB data structure
 550  * could not be allocated.
 551  *
 552  * @param proto the protocol number of the IPs payload (e.g. IP_PROTO_ICMP)
 553  *
 554  * @see raw_remove()
 555  */
 556 struct raw_pcb *
 557 raw_new(u8_t proto)
 558 {
 559   struct raw_pcb *pcb;
 560
 561   LWIP_DEBUGF(RAW_DEBUG | LWIP_DBG_TRACE, ("raw_new\n"));
 562
 563   pcb = (struct raw_pcb *)memp_malloc(MEMP_RAW_PCB);
 564   /* could allocate RAW PCB? */
 565   if (pcb != NULL) {
 566     /* initialize PCB to all zeroes */
 567     memset(pcb, 0, sizeof(struct raw_pcb));
 568     pcb->protocol = proto;
 569     pcb->ttl = RAW_TTL;
 570 #if LWIP_MULTICAST_TX_OPTIONS
 571     raw_set_multicast_ttl(pcb, RAW_TTL);
 572 #endif /* LWIP_MULTICAST_TX_OPTIONS */
 573     pcb->next = raw_pcbs;
 574     raw_pcbs = pcb;
 575   }
 576   return pcb;
 577 }
 578
 579 /**
 580  * @ingroup raw_raw
 581  * Create a RAW PCB for specific IP type.
 582  *
 583  * @return The RAW PCB which was created. NULL if the PCB data structure
 584  * could not be allocated.
 585  *
 586  * @param type IP address type, see @ref lwip_ip_addr_type definitions.
 587  * If you want to listen to IPv4 and IPv6 (dual-stack) packets,
 588  * supply @ref IPADDR_TYPE_ANY as argument and bind to @ref IP_ANY_TYPE.
 589  * @param proto the protocol number (next header) of the IPv6 packet payload
 590  *              (e.g. IP6_NEXTH_ICMP6)
 591  *
 592  * @see raw_remove()
 593  */
 594 struct raw_pcb *
 595 raw_new_ip_type(u8_t type, u8_t proto)
 596 {
 597   struct raw_pcb *pcb;
 598   pcb = raw_new(proto);
 599 #if LWIP_IPV4 && LWIP_IPV6
 600   if (pcb != NULL) {
 601     IP_SET_TYPE_VAL(pcb->local_ip,  type);
 602     IP_SET_TYPE_VAL(pcb->remote_ip, type);
 603   }
 604 #else /* LWIP_IPV4 && LWIP_IPV6 */
 605   LWIP_UNUSED_ARG(type);
 606 #endif /* LWIP_IPV4 && LWIP_IPV6 */
 607   return pcb;
 608 }
 609
 610 /** This function is called from netif.c when address is changed
 611  *
 612  * @param old_addr IP address of the netif before change
 613  * @param new_addr IP address of the netif after change
 614  */
 615 void raw_netif_ip_addr_changed(const ip_addr_t* old_addr, const ip_addr_t* new_addr)
 616 {
 617   struct raw_pcb* rpcb;
 618
 619   if (!ip_addr_isany(old_addr) && !ip_addr_isany(new_addr)) {
 620     for (rpcb = raw_pcbs; rpcb != NULL; rpcb = rpcb->next) {
 621       /* PCB bound to current local interface address? */
 622       if (ip_addr_cmp(&rpcb->local_ip, old_addr)) {
 623         /* The PCB is bound to the old ipaddr and
 624          * is set to bound to the new one instead */
 625         ip_addr_copy(rpcb->local_ip, *new_addr);
 626       }
 627     }
 628   }
 629 }
 630
 631 #endif /* LWIP_RAW */