minix/lib/liblwip/dist/src/netif/ethernet.c

   1 /**
   2  * @file
   3  * Ethernet common functions
   4  *
   5  * @defgroup ethernet Ethernet
   6  * @ingroup callbackstyle_api
   7  */
   8
   9 /*
  10  * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
  11  * Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
  12  * Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
  13  * All rights reserved.
  14  *
  15  * Redistribution and use in source and binary forms, with or without modification,
  16  * are permitted provided that the following conditions are met:
  17  *
  18  * 1. Redistributions of source code must retain the above copyright notice,
  19  *    this list of conditions and the following disclaimer.
  20  * 2. Redistributions in binary form must reproduce the above copyright notice,
  21  *    this list of conditions and the following disclaimer in the documentation
  22  *    and/or other materials provided with the distribution.
  23  * 3. The name of the author may not be used to endorse or promote products
  24  *    derived from this software without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  27  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  28  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  29  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  30  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  31  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  34  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  35  * OF SUCH DAMAGE.
  36  *
  37  * This file is part of the lwIP TCP/IP stack.
  38  *
  39  */
  40
  41 #include "lwip/opt.h"
  42
  43 #if LWIP_ARP || LWIP_ETHERNET
  44
  45 #include "netif/ethernet.h"
  46 #include "lwip/def.h"
  47 #include "lwip/stats.h"
  48 #include "lwip/etharp.h"
  49 #include "lwip/ip.h"
  50 #include "lwip/snmp.h"
  51
  52 #include <string.h>
  53
  54 #include "netif/ppp/ppp_opts.h"
  55 #if PPPOE_SUPPORT
  56 #include "netif/ppp/pppoe.h"
  57 #endif /* PPPOE_SUPPORT */
  58
  59 #ifdef LWIP_HOOK_FILENAME
  60 #include LWIP_HOOK_FILENAME
  61 #endif
  62
  63 const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
  64 const struct eth_addr ethzero = {{0,0,0,0,0,0}};
  65
  66 /**
  67  * @ingroup lwip_nosys
  68  * Process received ethernet frames. Using this function instead of directly
  69  * calling ip_input and passing ARP frames through etharp in ethernetif_input,
  70  * the ARP cache is protected from concurrent access.\n
  71  * Don't call directly, pass to netif_add() and call netif->input().
  72  *
  73  * @param p the received packet, p->payload pointing to the ethernet header
  74  * @param netif the network interface on which the packet was received
  75  *
  76  * @see LWIP_HOOK_UNKNOWN_ETH_PROTOCOL
  77  * @see ETHARP_SUPPORT_VLAN
  78  * @see LWIP_HOOK_VLAN_CHECK
  79  */
  80 err_t
  81 ethernet_input(struct pbuf *p, struct netif *netif)
  82 {
  83   struct eth_hdr* ethhdr;
  84   u16_t type;
  85 #if LWIP_ARP || ETHARP_SUPPORT_VLAN || LWIP_IPV6
  86   s16_t ip_hdr_offset = SIZEOF_ETH_HDR;
  87 #endif /* LWIP_ARP || ETHARP_SUPPORT_VLAN */
  88
  89   if (p->len <= SIZEOF_ETH_HDR) {
  90     /* a packet with only an ethernet header (or less) is not valid for us */
  91     ETHARP_STATS_INC(etharp.proterr);
  92     ETHARP_STATS_INC(etharp.drop);
  93     MIB2_STATS_NETIF_INC(netif, ifinerrors);
  94     goto free_and_return;
  95   }
  96
  97   if (p->if_idx == NETIF_NO_INDEX) {
  98     p->if_idx = netif_get_index(netif);
  99   }
 100
 101   /* points to packet payload, which starts with an Ethernet header */
 102   ethhdr = (struct eth_hdr *)p->payload;
 103   LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE,
 104     ("ethernet_input: dest:%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F", src:%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F", type:%"X16_F"\n",
 105      (unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
 106      (unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
 107      (unsigned)ethhdr->src.addr[0],  (unsigned)ethhdr->src.addr[1],  (unsigned)ethhdr->src.addr[2],
 108      (unsigned)ethhdr->src.addr[3],  (unsigned)ethhdr->src.addr[4],  (unsigned)ethhdr->src.addr[5],
 109      lwip_htons(ethhdr->type)));
 110
 111   type = ethhdr->type;
 112 #if ETHARP_SUPPORT_VLAN
 113   if (type == PP_HTONS(ETHTYPE_VLAN)) {
 114     struct eth_vlan_hdr *vlan = (struct eth_vlan_hdr*)(((char*)ethhdr) + SIZEOF_ETH_HDR);
 115     if (p->len <= SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR) {
 116       /* a packet with only an ethernet/vlan header (or less) is not valid for us */
 117       ETHARP_STATS_INC(etharp.proterr);
 118       ETHARP_STATS_INC(etharp.drop);
 119       MIB2_STATS_NETIF_INC(netif, ifinerrors);
 120       goto free_and_return;
 121     }
 122 #if defined(LWIP_HOOK_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK_FN) /* if not, allow all VLANs */
 123 #ifdef LWIP_HOOK_VLAN_CHECK
 124     if (!LWIP_HOOK_VLAN_CHECK(netif, ethhdr, vlan)) {
 125 #elif defined(ETHARP_VLAN_CHECK_FN)
 126     if (!ETHARP_VLAN_CHECK_FN(ethhdr, vlan)) {
 127 #elif defined(ETHARP_VLAN_CHECK)
 128     if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
 129 #endif
 130       /* silently ignore this packet: not for our VLAN */
 131       pbuf_free(p);
 132       return ERR_OK;
 133     }
 134 #endif /* defined(LWIP_HOOK_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK_FN) */
 135     type = vlan->tpid;
 136     ip_hdr_offset = SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR;
 137   }
 138 #endif /* ETHARP_SUPPORT_VLAN */
 139
 140 #if LWIP_ARP_FILTER_NETIF
 141   netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, lwip_htons(type));
 142 #endif /* LWIP_ARP_FILTER_NETIF*/
 143
 144   if (ethhdr->dest.addr[0] & 1) {
 145     /* this might be a multicast or broadcast packet */
 146     if (ethhdr->dest.addr[0] == LL_IP4_MULTICAST_ADDR_0) {
 147 #if LWIP_IPV4
 148       if ((ethhdr->dest.addr[1] == LL_IP4_MULTICAST_ADDR_1) &&
 149           (ethhdr->dest.addr[2] == LL_IP4_MULTICAST_ADDR_2)) {
 150         /* mark the pbuf as link-layer multicast */
 151         p->flags |= PBUF_FLAG_LLMCAST;
 152       }
 153 #endif /* LWIP_IPV4 */
 154     }
 155 #if LWIP_IPV6
 156     else if ((ethhdr->dest.addr[0] == LL_IP6_MULTICAST_ADDR_0) &&
 157              (ethhdr->dest.addr[1] == LL_IP6_MULTICAST_ADDR_1)) {
 158         /* mark the pbuf as link-layer multicast */
 159         p->flags |= PBUF_FLAG_LLMCAST;
 160     }
 161 #endif /* LWIP_IPV6 */
 162     else if (eth_addr_cmp(&ethhdr->dest, &ethbroadcast)) {
 163       /* mark the pbuf as link-layer broadcast */
 164       p->flags |= PBUF_FLAG_LLBCAST;
 165     }
 166   }
 167
 168   switch (type) {
 169 #if LWIP_IPV4 && LWIP_ARP
 170     /* IP packet? */
 171     case PP_HTONS(ETHTYPE_IP):
 172       if (!(netif->flags & NETIF_FLAG_ETHARP)) {
 173         goto free_and_return;
 174       }
 175       /* skip Ethernet header */
 176       if ((p->len < ip_hdr_offset) || pbuf_header(p, (s16_t)-ip_hdr_offset)) {
 177         LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
 178           ("ethernet_input: IPv4 packet dropped, too short (%"S16_F"/%"S16_F")\n",
 179           p->tot_len, ip_hdr_offset));
 180         LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("Can't move over header in packet"));
 181         goto free_and_return;
 182       } else {
 183         /* pass to IP layer */
 184         ip4_input(p, netif);
 185       }
 186       break;
 187
 188     case PP_HTONS(ETHTYPE_ARP):
 189       if (!(netif->flags & NETIF_FLAG_ETHARP)) {
 190         goto free_and_return;
 191       }
 192       /* skip Ethernet header */
 193       if ((p->len < ip_hdr_offset) || pbuf_header(p, (s16_t)-ip_hdr_offset)) {
 194         LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
 195           ("ethernet_input: ARP response packet dropped, too short (%"S16_F"/%"S16_F")\n",
 196           p->tot_len, ip_hdr_offset));
 197         LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("Can't move over header in packet"));
 198         ETHARP_STATS_INC(etharp.lenerr);
 199         ETHARP_STATS_INC(etharp.drop);
 200         goto free_and_return;
 201       } else {
 202         /* pass p to ARP module */
 203         etharp_input(p, netif);
 204       }
 205       break;
 206 #endif /* LWIP_IPV4 && LWIP_ARP */
 207 #if PPPOE_SUPPORT
 208     case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
 209       pppoe_disc_input(netif, p);
 210       break;
 211
 212     case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
 213       pppoe_data_input(netif, p);
 214       break;
 215 #endif /* PPPOE_SUPPORT */
 216
 217 #if LWIP_IPV6
 218     case PP_HTONS(ETHTYPE_IPV6): /* IPv6 */
 219       /* skip Ethernet header */
 220       if ((p->len < ip_hdr_offset) || pbuf_header(p, (s16_t)-ip_hdr_offset)) {
 221         LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
 222           ("ethernet_input: IPv6 packet dropped, too short (%"S16_F"/%"S16_F")\n",
 223           p->tot_len, ip_hdr_offset));
 224         goto free_and_return;
 225       } else {
 226         /* pass to IPv6 layer */
 227         ip6_input(p, netif);
 228       }
 229       break;
 230 #endif /* LWIP_IPV6 */
 231
 232     default:
 233 #ifdef LWIP_HOOK_UNKNOWN_ETH_PROTOCOL
 234       if(LWIP_HOOK_UNKNOWN_ETH_PROTOCOL(p, netif) == ERR_OK) {
 235         break;
 236       }
 237 #endif
 238       ETHARP_STATS_INC(etharp.proterr);
 239       ETHARP_STATS_INC(etharp.drop);
 240       MIB2_STATS_NETIF_INC(netif, ifinunknownprotos);
 241       goto free_and_return;
 242   }
 243
 244   /* This means the pbuf is freed or consumed,
 245      so the caller doesn't have to free it again */
 246   return ERR_OK;
 247
 248 free_and_return:
 249   pbuf_free(p);
 250   return ERR_OK;
 251 }
 252
 253 /**
 254  * @ingroup ethernet
 255  * Send an ethernet packet on the network using netif->linkoutput().
 256  * The ethernet header is filled in before sending.
 257  *
 258  * @see LWIP_HOOK_VLAN_SET
 259  *
 260  * @param netif the lwIP network interface on which to send the packet
 261  * @param p the packet to send. pbuf layer must be @ref PBUF_LINK.
 262  * @param src the source MAC address to be copied into the ethernet header
 263  * @param dst the destination MAC address to be copied into the ethernet header
 264  * @param eth_type ethernet type (@ref eth_type)
 265  * @return ERR_OK if the packet was sent, any other err_t on failure
 266  */
 267 err_t
 268 ethernet_output(struct netif* netif, struct pbuf* p,
 269                 const struct eth_addr* src, const struct eth_addr* dst,
 270                 u16_t eth_type)
 271 {
 272   struct eth_hdr* ethhdr;
 273   u16_t eth_type_be = lwip_htons(eth_type);
 274
 275 #if ETHARP_SUPPORT_VLAN && defined(LWIP_HOOK_VLAN_SET)
 276   s32_t vlan_prio_vid = LWIP_HOOK_VLAN_SET(netif, p, src, dst, eth_type);
 277   if (vlan_prio_vid >= 0) {
 278     struct eth_vlan_hdr* vlanhdr;
 279
 280     LWIP_ASSERT("prio_vid must be <= 0xFFFF", vlan_prio_vid <= 0xFFFF);
 281
 282     if (pbuf_header(p, SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR) != 0) {
 283       goto pbuf_header_failed;
 284     }
 285     vlanhdr = (struct eth_vlan_hdr*)(((u8_t*)p->payload) + SIZEOF_ETH_HDR);
 286     vlanhdr->tpid     = eth_type_be;
 287     vlanhdr->prio_vid = lwip_htons((u16_t)vlan_prio_vid);
 288
 289     eth_type_be = PP_HTONS(ETHTYPE_VLAN);
 290   } else
 291 #endif /* ETHARP_SUPPORT_VLAN && defined(LWIP_HOOK_VLAN_SET) */
 292   {
 293     if (pbuf_header(p, SIZEOF_ETH_HDR) != 0) {
 294       goto pbuf_header_failed;
 295     }
 296   }
 297
 298   ethhdr = (struct eth_hdr*)p->payload;
 299   ethhdr->type = eth_type_be;
 300   ETHADDR16_COPY(&ethhdr->dest, dst);
 301   ETHADDR16_COPY(&ethhdr->src,  src);
 302
 303   LWIP_ASSERT("netif->hwaddr_len must be 6 for ethernet_output!",
 304     (netif->hwaddr_len == ETH_HWADDR_LEN));
 305   LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE,
 306     ("ethernet_output: sending packet %p\n", (void *)p));
 307
 308   /* send the packet */
 309   return netif->linkoutput(netif, p);
 310
 311 pbuf_header_failed:
 312   LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
 313     ("ethernet_output: could not allocate room for header.\n"));
 314   LINK_STATS_INC(link.lenerr);
 315   return ERR_BUF;
 316 }
 317
 318 #endif /* LWIP_ARP || LWIP_ETHERNET */