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lwip_ethernet.c
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00001 /** 00002 * @file 00003 * Ethernet common functions 00004 * 00005 * @defgroup ethernet Ethernet 00006 * @ingroup callbackstyle_api 00007 */ 00008 00009 /* 00010 * Copyright (c) 2001-2003 Swedish Institute of Computer Science. 00011 * Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv> 00012 * Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands. 00013 * All rights reserved. 00014 * 00015 * Redistribution and use in source and binary forms, with or without modification, 00016 * are permitted provided that the following conditions are met: 00017 * 00018 * 1. Redistributions of source code must retain the above copyright notice, 00019 * this list of conditions and the following disclaimer. 00020 * 2. Redistributions in binary form must reproduce the above copyright notice, 00021 * this list of conditions and the following disclaimer in the documentation 00022 * and/or other materials provided with the distribution. 00023 * 3. The name of the author may not be used to endorse or promote products 00024 * derived from this software without specific prior written permission. 00025 * 00026 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 00027 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 00028 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 00029 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 00030 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 00031 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 00032 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 00033 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 00034 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 00035 * OF SUCH DAMAGE. 00036 * 00037 * This file is part of the lwIP TCP/IP stack. 00038 * 00039 */ 00040 00041 #include "lwip/opt.h" 00042 00043 #if LWIP_ARP || LWIP_ETHERNET 00044 00045 #include "netif/lwip_ethernet.h" 00046 #include "lwip/def.h" 00047 #include "lwip/stats.h" 00048 #include "lwip/etharp.h" 00049 #include "lwip/ip.h" 00050 #include "lwip/snmp.h" 00051 00052 #include <string.h> 00053 00054 #include "netif/ppp/ppp_opts.h" 00055 #if PPPOE_SUPPORT 00056 #include "netif/ppp/pppoe.h" 00057 #endif /* PPPOE_SUPPORT */ 00058 00059 #ifdef LWIP_HOOK_FILENAME 00060 #include LWIP_HOOK_FILENAME 00061 #endif 00062 00063 const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}}; 00064 const struct eth_addr ethzero = {{0,0,0,0,0,0}}; 00065 00066 /** 00067 * @ingroup lwip_nosys 00068 * Process received ethernet frames. Using this function instead of directly 00069 * calling ip_input and passing ARP frames through etharp in ethernetif_input, 00070 * the ARP cache is protected from concurrent access.\n 00071 * Don't call directly, pass to netif_add() and call netif->input(). 00072 * 00073 * @param p the received packet, p->payload pointing to the ethernet header 00074 * @param netif the network interface on which the packet was received 00075 * 00076 * @see LWIP_HOOK_UNKNOWN_ETH_PROTOCOL 00077 * @see ETHARP_SUPPORT_VLAN 00078 * @see LWIP_HOOK_VLAN_CHECK 00079 */ 00080 err_t 00081 ethernet_input(struct pbuf *p, struct netif *netif) 00082 { 00083 struct eth_hdr* ethhdr; 00084 u16_t type; 00085 #if LWIP_ARP || ETHARP_SUPPORT_VLAN || LWIP_IPV6 00086 s16_t ip_hdr_offset = SIZEOF_ETH_HDR; 00087 #endif /* LWIP_ARP || ETHARP_SUPPORT_VLAN */ 00088 00089 if (p->len <= SIZEOF_ETH_HDR) { 00090 /* a packet with only an ethernet header (or less) is not valid for us */ 00091 ETHARP_STATS_INC(etharp.proterr); 00092 ETHARP_STATS_INC(etharp.drop); 00093 MIB2_STATS_NETIF_INC(netif, ifinerrors); 00094 goto free_and_return; 00095 } 00096 00097 /* points to packet payload, which starts with an Ethernet header */ 00098 ethhdr = (struct eth_hdr *)p->payload; 00099 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, 00100 ("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", 00101 (unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2], 00102 (unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5], 00103 (unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2], 00104 (unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5], 00105 lwip_htons(ethhdr->type))); 00106 00107 type = ethhdr->type; 00108 #if ETHARP_SUPPORT_VLAN 00109 if (type == PP_HTONS(ETHTYPE_VLAN)) { 00110 struct eth_vlan_hdr *vlan = (struct eth_vlan_hdr*)(((char*)ethhdr) + SIZEOF_ETH_HDR); 00111 if (p->len <= SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR) { 00112 /* a packet with only an ethernet/vlan header (or less) is not valid for us */ 00113 ETHARP_STATS_INC(etharp.proterr); 00114 ETHARP_STATS_INC(etharp.drop); 00115 MIB2_STATS_NETIF_INC(netif, ifinerrors); 00116 goto free_and_return; 00117 } 00118 #if defined(LWIP_HOOK_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK_FN) /* if not, allow all VLANs */ 00119 #ifdef LWIP_HOOK_VLAN_CHECK 00120 if (!LWIP_HOOK_VLAN_CHECK(netif, ethhdr, vlan)) { 00121 #elif defined(ETHARP_VLAN_CHECK_FN) 00122 if (!ETHARP_VLAN_CHECK_FN(ethhdr, vlan)) { 00123 #elif defined(ETHARP_VLAN_CHECK) 00124 if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) { 00125 #endif 00126 /* silently ignore this packet: not for our VLAN */ 00127 pbuf_free(p); 00128 return ERR_OK; 00129 } 00130 #endif /* defined(LWIP_HOOK_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK) || defined(ETHARP_VLAN_CHECK_FN) */ 00131 type = vlan->tpid; 00132 ip_hdr_offset = SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR; 00133 } 00134 #endif /* ETHARP_SUPPORT_VLAN */ 00135 00136 #if LWIP_ARP_FILTER_NETIF 00137 netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, lwip_htons(type)); 00138 #endif /* LWIP_ARP_FILTER_NETIF*/ 00139 00140 if (ethhdr->dest.addr[0] & 1) { 00141 /* this might be a multicast or broadcast packet */ 00142 if (ethhdr->dest.addr[0] == LL_IP4_MULTICAST_ADDR_0) { 00143 #if LWIP_IPV4 00144 if ((ethhdr->dest.addr[1] == LL_IP4_MULTICAST_ADDR_1) && 00145 (ethhdr->dest.addr[2] == LL_IP4_MULTICAST_ADDR_2)) { 00146 /* mark the pbuf as link-layer multicast */ 00147 p->flags |= PBUF_FLAG_LLMCAST; 00148 } 00149 #endif /* LWIP_IPV4 */ 00150 } 00151 #if LWIP_IPV6 00152 else if ((ethhdr->dest.addr[0] == LL_IP6_MULTICAST_ADDR_0) && 00153 (ethhdr->dest.addr[1] == LL_IP6_MULTICAST_ADDR_1)) { 00154 /* mark the pbuf as link-layer multicast */ 00155 p->flags |= PBUF_FLAG_LLMCAST; 00156 } 00157 #endif /* LWIP_IPV6 */ 00158 else if (eth_addr_cmp(ðhdr->dest, ðbroadcast)) { 00159 /* mark the pbuf as link-layer broadcast */ 00160 p->flags |= PBUF_FLAG_LLBCAST; 00161 } 00162 } 00163 00164 switch (type) { 00165 #if LWIP_IPV4 && LWIP_ARP 00166 /* IP packet? */ 00167 case PP_HTONS(ETHTYPE_IP): 00168 if (!(netif->flags & NETIF_FLAG_ETHARP)) { 00169 goto free_and_return; 00170 } 00171 /* skip Ethernet header */ 00172 if ((p->len < ip_hdr_offset) || pbuf_header(p, (s16_t)-ip_hdr_offset)) { 00173 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, 00174 ("ethernet_input: IPv4 packet dropped, too short (%"S16_F"/%"S16_F")\n", 00175 p->tot_len, ip_hdr_offset)); 00176 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("Can't move over header in packet")); 00177 goto free_and_return; 00178 } else { 00179 /* pass to IP layer */ 00180 ip4_input(p, netif); 00181 } 00182 break; 00183 00184 case PP_HTONS(ETHTYPE_ARP): 00185 if (!(netif->flags & NETIF_FLAG_ETHARP)) { 00186 goto free_and_return; 00187 } 00188 /* skip Ethernet header */ 00189 if ((p->len < ip_hdr_offset) || pbuf_header(p, (s16_t)-ip_hdr_offset)) { 00190 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, 00191 ("ethernet_input: ARP response packet dropped, too short (%"S16_F"/%"S16_F")\n", 00192 p->tot_len, ip_hdr_offset)); 00193 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("Can't move over header in packet")); 00194 ETHARP_STATS_INC(etharp.lenerr); 00195 ETHARP_STATS_INC(etharp.drop); 00196 goto free_and_return; 00197 } else { 00198 /* pass p to ARP module */ 00199 etharp_input(p, netif); 00200 } 00201 break; 00202 #endif /* LWIP_IPV4 && LWIP_ARP */ 00203 #if PPPOE_SUPPORT 00204 case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */ 00205 pppoe_disc_input(netif, p); 00206 break; 00207 00208 case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */ 00209 pppoe_data_input(netif, p); 00210 break; 00211 #endif /* PPPOE_SUPPORT */ 00212 00213 #if LWIP_IPV6 00214 case PP_HTONS(ETHTYPE_IPV6): /* IPv6 */ 00215 /* skip Ethernet header */ 00216 if ((p->len < ip_hdr_offset) || pbuf_header(p, (s16_t)-ip_hdr_offset)) { 00217 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING, 00218 ("ethernet_input: IPv6 packet dropped, too short (%"S16_F"/%"S16_F")\n", 00219 p->tot_len, ip_hdr_offset)); 00220 goto free_and_return; 00221 } else { 00222 /* pass to IPv6 layer */ 00223 ip6_input(p, netif); 00224 } 00225 break; 00226 #endif /* LWIP_IPV6 */ 00227 00228 default: 00229 #ifdef LWIP_HOOK_UNKNOWN_ETH_PROTOCOL 00230 if(LWIP_HOOK_UNKNOWN_ETH_PROTOCOL(p, netif) == ERR_OK) { 00231 break; 00232 } 00233 #endif 00234 ETHARP_STATS_INC(etharp.proterr); 00235 ETHARP_STATS_INC(etharp.drop); 00236 MIB2_STATS_NETIF_INC(netif, ifinunknownprotos); 00237 goto free_and_return; 00238 } 00239 00240 /* This means the pbuf is freed or consumed, 00241 so the caller doesn't have to free it again */ 00242 return ERR_OK; 00243 00244 free_and_return: 00245 pbuf_free(p); 00246 return ERR_OK; 00247 } 00248 00249 /** 00250 * @ingroup ethernet 00251 * Send an ethernet packet on the network using netif->linkoutput(). 00252 * The ethernet header is filled in before sending. 00253 * 00254 * @see LWIP_HOOK_VLAN_SET 00255 * 00256 * @param netif the lwIP network interface on which to send the packet 00257 * @param p the packet to send. pbuf layer must be @ref PBUF_LINK. 00258 * @param src the source MAC address to be copied into the ethernet header 00259 * @param dst the destination MAC address to be copied into the ethernet header 00260 * @param eth_type ethernet type (@ref eth_type) 00261 * @return ERR_OK if the packet was sent, any other err_t on failure 00262 */ 00263 err_t 00264 ethernet_output(struct netif* netif, struct pbuf* p, 00265 const struct eth_addr* src, const struct eth_addr* dst, 00266 u16_t eth_type) 00267 { 00268 struct eth_hdr* ethhdr; 00269 u16_t eth_type_be = lwip_htons(eth_type); 00270 00271 #if ETHARP_SUPPORT_VLAN && defined(LWIP_HOOK_VLAN_SET) 00272 s32_t vlan_prio_vid = LWIP_HOOK_VLAN_SET(netif, p, src, dst, eth_type); 00273 if (vlan_prio_vid >= 0) { 00274 struct eth_vlan_hdr* vlanhdr; 00275 00276 LWIP_ASSERT("prio_vid must be <= 0xFFFF", vlan_prio_vid <= 0xFFFF); 00277 00278 if (pbuf_header(p, SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR) != 0) { 00279 goto pbuf_header_failed; 00280 } 00281 vlanhdr = (struct eth_vlan_hdr*)(((u8_t*)p->payload) + SIZEOF_ETH_HDR); 00282 vlanhdr->tpid = eth_type_be; 00283 vlanhdr->prio_vid = lwip_htons((u16_t)vlan_prio_vid); 00284 00285 eth_type_be = PP_HTONS(ETHTYPE_VLAN); 00286 } else 00287 #endif /* ETHARP_SUPPORT_VLAN && defined(LWIP_HOOK_VLAN_SET) */ 00288 { 00289 if (pbuf_header(p, SIZEOF_ETH_HDR) != 0) { 00290 goto pbuf_header_failed; 00291 } 00292 } 00293 00294 ethhdr = (struct eth_hdr*)p->payload; 00295 ethhdr->type = eth_type_be; 00296 ETHADDR32_COPY(ðhdr->dest, dst); 00297 ETHADDR16_COPY(ðhdr->src, src); 00298 00299 LWIP_ASSERT("netif->hwaddr_len must be 6 for ethernet_output!", 00300 (netif->hwaddr_len == ETH_HWADDR_LEN)); 00301 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, 00302 ("ethernet_output: sending packet %p\n", (void *)p)); 00303 00304 /* send the packet */ 00305 return netif->linkoutput(netif, p); 00306 00307 pbuf_header_failed: 00308 LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS, 00309 ("ethernet_output: could not allocate room for header.\n")); 00310 LINK_STATS_INC(link.lenerr); 00311 return ERR_BUF; 00312 } 00313 00314 #endif /* LWIP_ARP || LWIP_ETHERNET */
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