-/**
- * \addtogroup uip
- * @{
- */
-
-/**
- * \defgroup uiparp uIP Address Resolution Protocol
- * @{
- *
- * The Address Resolution Protocol ARP is used for mapping between IP
- * addresses and link level addresses such as the Ethernet MAC
- * addresses. ARP uses broadcast queries to ask for the link level
- * address of a known IP address and the host which is configured with
- * the IP address for which the query was meant, will respond with its
- * link level address.
- *
- * \note This ARP implementation only supports Ethernet.
- */
-
-/**
- * \file
- * Implementation of the ARP Address Resolution Protocol.
- * \author Adam Dunkels <adam@dunkels.com>
- *
- */
-
-/*
- * Copyright (c) 2001-2003, Adam Dunkels.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote
- * products derived from this software without specific prior
- * written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
- * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
- * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
- * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- * This file is part of the uIP TCP/IP stack.
- *
- * $Id: uip_arp.c,v 1.5 2008/02/07 01:35:00 adamdunkels Exp $
- *
- */
-
-
-#include "uip_arp.h"
-
-#include <string.h>
-
-struct arp_hdr {
- struct uip_eth_hdr ethhdr;
- u16_t hwtype;
- u16_t protocol;
- u8_t hwlen;
- u8_t protolen;
- u16_t opcode;
- struct uip_eth_addr shwaddr;
- uip_ipaddr_t sipaddr;
- struct uip_eth_addr dhwaddr;
- uip_ipaddr_t dipaddr;
-};
-
-struct ethip_hdr {
- struct uip_eth_hdr ethhdr;
- /* IP header. */
- u8_t vhl,
- tos,
- len[2],
- ipid[2],
- ipoffset[2],
- ttl,
- proto;
- u16_t ipchksum;
- uip_ipaddr_t srcipaddr, destipaddr;
-};
-
-#define ARP_REQUEST 1
-#define ARP_REPLY 2
-
-#define ARP_HWTYPE_ETH 1
-
-struct arp_entry {
- uip_ipaddr_t ipaddr;
- struct uip_eth_addr ethaddr;
- u8_t time;
-};
-
-static const struct uip_eth_addr broadcast_ethaddr =
- {{0xff,0xff,0xff,0xff,0xff,0xff}};
-static const u16_t broadcast_ipaddr[2] = {0xffff,0xffff};
-
-static struct arp_entry arp_table[UIP_ARPTAB_SIZE];
-static uip_ipaddr_t ipaddr;
-static u8_t i, c;
-
-static u8_t arptime;
-static u8_t tmpage;
-
-#define BUF ((struct arp_hdr *)&uip_buf[0])
-#define IPBUF ((struct ethip_hdr *)&uip_buf[0])
-
-#define DEBUG 0
-#if DEBUG
-#include <stdio.h>
-#define PRINTF(...) printf(__VA_ARGS__)
-#else
-#define PRINTF(...)
-#endif
-
-/*-----------------------------------------------------------------------------------*/
-/**
- * Initialize the ARP module.
- *
- */
-/*-----------------------------------------------------------------------------------*/
-void
-uip_arp_init(void)
-{
- for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {
- memset(&arp_table[i].ipaddr, 0, 4);
- }
-}
-/*-----------------------------------------------------------------------------------*/
-/**
- * Periodic ARP processing function.
- *
- * This function performs periodic timer processing in the ARP module
- * and should be called at regular intervals. The recommended interval
- * is 10 seconds between the calls.
- *
- */
-/*-----------------------------------------------------------------------------------*/
-void
-uip_arp_timer(void)
-{
- struct arp_entry *tabptr = NULL;
-
- ++arptime;
- for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {
- tabptr = &arp_table[i];
- if(uip_ipaddr_cmp(&tabptr->ipaddr, &uip_all_zeroes_addr) &&
- arptime - tabptr->time >= UIP_ARP_MAXAGE) {
- memset(&tabptr->ipaddr, 0, 4);
- }
- }
-
-}
-/*-----------------------------------------------------------------------------------*/
-static void
-uip_arp_update(uip_ipaddr_t *ipaddr, struct uip_eth_addr *ethaddr)
-{
- register struct arp_entry *tabptr = NULL;
- /* Walk through the ARP mapping table and try to find an entry to
- update. If none is found, the IP -> MAC address mapping is
- inserted in the ARP table. */
- for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {
-
- tabptr = &arp_table[i];
- /* Only check those entries that are actually in use. */
- if(!uip_ipaddr_cmp(&tabptr->ipaddr, &uip_all_zeroes_addr)) {
-
- /* Check if the source IP address of the incoming packet matches
- the IP address in this ARP table entry. */
- if(uip_ipaddr_cmp(ipaddr, &tabptr->ipaddr)) {
-
- /* An old entry found, update this and return. */
- memcpy(tabptr->ethaddr.addr, ethaddr->addr, 6);
- tabptr->time = arptime;
-
- return;
- }
- }
- }
-
- /* If we get here, no existing ARP table entry was found, so we
- create one. */
-
- /* First, we try to find an unused entry in the ARP table. */
- for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {
- tabptr = &arp_table[i];
- if(uip_ipaddr_cmp(&tabptr->ipaddr, &uip_all_zeroes_addr)) {
- break;
- }
- }
-
- /* If no unused entry is found, we try to find the oldest entry and
- throw it away. */
- if(i == UIP_ARPTAB_SIZE) {
- tmpage = 0;
- c = 0;
- for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {
- tabptr = &arp_table[i];
- if(arptime - tabptr->time > tmpage) {
- tmpage = arptime - tabptr->time;
- c = i;
- }
- }
- i = c;
- tabptr = &arp_table[i];
- }
-
- /* Now, i is the ARP table entry which we will fill with the new
- information. */
- uip_ipaddr_copy(&tabptr->ipaddr, ipaddr);
- memcpy(tabptr->ethaddr.addr, ethaddr->addr, 6);
- tabptr->time = arptime;
-}
-/*-----------------------------------------------------------------------------------*/
-/**
- * ARP processing for incoming IP packets
- *
- * This function should be called by the device driver when an IP
- * packet has been received. The function will check if the address is
- * in the ARP cache, and if so the ARP cache entry will be
- * refreshed. If no ARP cache entry was found, a new one is created.
- *
- * This function expects an IP packet with a prepended Ethernet header
- * in the uip_buf[] buffer, and the length of the packet in the global
- * variable uip_len.
- */
-/*-----------------------------------------------------------------------------------*/
-#if 0
-void
-uip_arp_ipin(void)
-{
- uip_len -= sizeof(struct uip_eth_hdr);
-
- /* Only insert/update an entry if the source IP address of the
- incoming IP packet comes from a host on the local network. */
- if((IPBUF->srcipaddr[0] & uip_netmask[0]) !=
- (uip_hostaddr[0] & uip_netmask[0])) {
- return;
- }
- if((IPBUF->srcipaddr[1] & uip_netmask[1]) !=
- (uip_hostaddr[1] & uip_netmask[1])) {
- return;
- }
- uip_arp_update(IPBUF->srcipaddr, &(IPBUF->ethhdr.src));
-
- return;
-}
-#endif /* 0 */
-/*-----------------------------------------------------------------------------------*/
-/**
- * ARP processing for incoming ARP packets.
- *
- * This function should be called by the device driver when an ARP
- * packet has been received. The function will act differently
- * depending on the ARP packet type: if it is a reply for a request
- * that we previously sent out, the ARP cache will be filled in with
- * the values from the ARP reply. If the incoming ARP packet is an ARP
- * request for our IP address, an ARP reply packet is created and put
- * into the uip_buf[] buffer.
- *
- * When the function returns, the value of the global variable uip_len
- * indicates whether the device driver should send out a packet or
- * not. If uip_len is zero, no packet should be sent. If uip_len is
- * non-zero, it contains the length of the outbound packet that is
- * present in the uip_buf[] buffer.
- *
- * This function expects an ARP packet with a prepended Ethernet
- * header in the uip_buf[] buffer, and the length of the packet in the
- * global variable uip_len.
- */
-/*-----------------------------------------------------------------------------------*/
-void
-uip_arp_arpin(void)
-{
- if(uip_len < sizeof(struct arp_hdr)) {
- uip_len = 0;
- return;
- }
- uip_len = 0;
-
- switch(BUF->opcode) {
- case HTONS(ARP_REQUEST):
- /* ARP request. If it asked for our address, we send out a
- reply. */
- /* if(BUF->dipaddr[0] == uip_hostaddr[0] &&
- BUF->dipaddr[1] == uip_hostaddr[1]) {*/
- PRINTF("uip_arp_arpin: request for %d.%d.%d.%d (we are %d.%d.%d.%d)\n",
- BUF->dipaddr.u8[0], BUF->dipaddr.u8[1],
- BUF->dipaddr.u8[2], BUF->dipaddr.u8[3],
- uip_hostaddr.u8[0], uip_hostaddr.u8[1],
- uip_hostaddr.u8[2], uip_hostaddr.u8[3]);
- if(uip_ipaddr_cmp(&BUF->dipaddr, &uip_hostaddr)) {
- /* First, we register the one who made the request in our ARP
- table, since it is likely that we will do more communication
- with this host in the future. */
- uip_arp_update(&BUF->sipaddr, &BUF->shwaddr);
-
- BUF->opcode = HTONS(ARP_REPLY);
-
- memcpy(BUF->dhwaddr.addr, BUF->shwaddr.addr, 6);
- memcpy(BUF->shwaddr.addr, uip_ethaddr.addr, 6);
- memcpy(BUF->ethhdr.src.addr, uip_ethaddr.addr, 6);
- memcpy(BUF->ethhdr.dest.addr, BUF->dhwaddr.addr, 6);
-
- uip_ipaddr_copy(&BUF->dipaddr, &BUF->sipaddr);
- uip_ipaddr_copy(&BUF->sipaddr, &uip_hostaddr);
-
- BUF->ethhdr.type = HTONS(UIP_ETHTYPE_ARP);
- uip_len = sizeof(struct arp_hdr);
- }
- break;
- case HTONS(ARP_REPLY):
- /* ARP reply. We insert or update the ARP table if it was meant
- for us. */
- if(uip_ipaddr_cmp(&BUF->dipaddr, &uip_hostaddr)) {
- uip_arp_update(&BUF->sipaddr, &BUF->shwaddr);
- }
- break;
- }
-
- return;
-}
-/*-----------------------------------------------------------------------------------*/
-/**
- * Prepend Ethernet header to an outbound IP packet and see if we need
- * to send out an ARP request.
- *
- * This function should be called before sending out an IP packet. The
- * function checks the destination IP address of the IP packet to see
- * what Ethernet MAC address that should be used as a destination MAC
- * address on the Ethernet.
- *
- * If the destination IP address is in the local network (determined
- * by logical ANDing of netmask and our IP address), the function
- * checks the ARP cache to see if an entry for the destination IP
- * address is found. If so, an Ethernet header is prepended and the
- * function returns. If no ARP cache entry is found for the
- * destination IP address, the packet in the uip_buf[] is replaced by
- * an ARP request packet for the IP address. The IP packet is dropped
- * and it is assumed that they higher level protocols (e.g., TCP)
- * eventually will retransmit the dropped packet.
- *
- * If the destination IP address is not on the local network, the IP
- * address of the default router is used instead.
- *
- * When the function returns, a packet is present in the uip_buf[]
- * buffer, and the length of the packet is in the global variable
- * uip_len.
- */
-/*-----------------------------------------------------------------------------------*/
-void
-uip_arp_out(void)
-{
- struct arp_entry *tabptr = NULL;
-
- /* Find the destination IP address in the ARP table and construct
- the Ethernet header. If the destination IP addres isn't on the
- local network, we use the default router's IP address instead.
-
- If not ARP table entry is found, we overwrite the original IP
- packet with an ARP request for the IP address. */
-
- /* First check if destination is a local broadcast. */
- if(uip_ipaddr_cmp(&IPBUF->destipaddr, &uip_broadcast_addr)) {
- memcpy(IPBUF->ethhdr.dest.addr, broadcast_ethaddr.addr, 6);
- } else {
- /* Check if the destination address is on the local network. */
- if(!uip_ipaddr_maskcmp(&IPBUF->destipaddr, &uip_hostaddr, &uip_netmask)) {
- /* Destination address was not on the local network, so we need to
- use the default router's IP address instead of the destination
- address when determining the MAC address. */
- uip_ipaddr_copy(&ipaddr, &uip_draddr);
- } else {
- /* Else, we use the destination IP address. */
- uip_ipaddr_copy(&ipaddr, &IPBUF->destipaddr);
- }
-
- for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {
- tabptr = &arp_table[i];
- if(uip_ipaddr_cmp(&ipaddr, &tabptr->ipaddr)) {
- break;
- }
- }
-
- if(i == UIP_ARPTAB_SIZE) {
- /* The destination address was not in our ARP table, so we
- overwrite the IP packet with an ARP request. */
-
- memset(BUF->ethhdr.dest.addr, 0xff, 6);
- memset(BUF->dhwaddr.addr, 0x00, 6);
- memcpy(BUF->ethhdr.src.addr, uip_ethaddr.addr, 6);
- memcpy(BUF->shwaddr.addr, uip_ethaddr.addr, 6);
-
- uip_ipaddr_copy(&BUF->dipaddr, &ipaddr);
- uip_ipaddr_copy(&BUF->sipaddr, &uip_hostaddr);
- BUF->opcode = HTONS(ARP_REQUEST); /* ARP request. */
- BUF->hwtype = HTONS(ARP_HWTYPE_ETH);
- BUF->protocol = HTONS(UIP_ETHTYPE_IP);
- BUF->hwlen = 6;
- BUF->protolen = 4;
- BUF->ethhdr.type = HTONS(UIP_ETHTYPE_ARP);
-
- uip_appdata = &uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN];
-
- uip_len = sizeof(struct arp_hdr);
- return;
- }
-
- /* Build an ethernet header. */
- memcpy(IPBUF->ethhdr.dest.addr, tabptr->ethaddr.addr, 6);
- }
- memcpy(IPBUF->ethhdr.src.addr, uip_ethaddr.addr, 6);
-
- IPBUF->ethhdr.type = HTONS(UIP_ETHTYPE_IP);
-
- uip_len += sizeof(struct uip_eth_hdr);
-}
-/*-----------------------------------------------------------------------------------*/
-
-/** @} */
-/** @} */
+/**\r
+ * \addtogroup uip\r
+ * @{\r
+ */\r
+\r
+/**\r
+ * \defgroup uiparp uIP Address Resolution Protocol\r
+ * @{\r
+ *\r
+ * The Address Resolution Protocol ARP is used for mapping between IP\r
+ * addresses and link level addresses such as the Ethernet MAC\r
+ * addresses. ARP uses broadcast queries to ask for the link level\r
+ * address of a known IP address and the host which is configured with\r
+ * the IP address for which the query was meant, will respond with its\r
+ * link level address.\r
+ *\r
+ * \note This ARP implementation only supports Ethernet.\r
+ */\r
+ \r
+/**\r
+ * \file\r
+ * Implementation of the ARP Address Resolution Protocol.\r
+ * \author Adam Dunkels <adam@dunkels.com>\r
+ *\r
+ */\r
+\r
+/*\r
+ * Copyright (c) 2001-2003, Adam Dunkels.\r
+ * All rights reserved.\r
+ *\r
+ * Redistribution and use in source and binary forms, with or without\r
+ * modification, are permitted provided that the following conditions\r
+ * are met:\r
+ * 1. Redistributions of source code must retain the above copyright\r
+ * notice, this list of conditions and the following disclaimer.\r
+ * 2. Redistributions in binary form must reproduce the above copyright\r
+ * notice, this list of conditions and the following disclaimer in the\r
+ * documentation and/or other materials provided with the distribution.\r
+ * 3. The name of the author may not be used to endorse or promote\r
+ * products derived from this software without specific prior\r
+ * written permission.\r
+ *\r
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS\r
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED\r
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\r
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY\r
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL\r
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE\r
+ * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS\r
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,\r
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING\r
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS\r
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\r
+ *\r
+ * This file is part of the uIP TCP/IP stack.\r
+ *\r
+ * $Id: uip_arp.c,v 1.5 2008/02/07 01:35:00 adamdunkels Exp $\r
+ *\r
+ */\r
+\r
+\r
+#include "uip_arp.h"\r
+\r
+#include <string.h>\r
+\r
+struct arp_hdr {\r
+ struct uip_eth_hdr ethhdr;\r
+ u16_t hwtype;\r
+ u16_t protocol;\r
+ u8_t hwlen;\r
+ u8_t protolen;\r
+ u16_t opcode;\r
+ struct uip_eth_addr shwaddr;\r
+ uip_ipaddr_t sipaddr;\r
+ struct uip_eth_addr dhwaddr;\r
+ uip_ipaddr_t dipaddr;\r
+};\r
+\r
+struct ethip_hdr {\r
+ struct uip_eth_hdr ethhdr;\r
+ /* IP header. */\r
+ u8_t vhl,\r
+ tos,\r
+ len[2],\r
+ ipid[2],\r
+ ipoffset[2],\r
+ ttl,\r
+ proto;\r
+ u16_t ipchksum;\r
+ uip_ipaddr_t srcipaddr, destipaddr;\r
+};\r
+\r
+#define ARP_REQUEST 1\r
+#define ARP_REPLY 2\r
+\r
+#define ARP_HWTYPE_ETH 1\r
+\r
+struct arp_entry {\r
+ uip_ipaddr_t ipaddr;\r
+ struct uip_eth_addr ethaddr;\r
+ u8_t time;\r
+};\r
+\r
+static const struct uip_eth_addr broadcast_ethaddr =\r
+ {{0xff,0xff,0xff,0xff,0xff,0xff}};\r
+static const u16_t broadcast_ipaddr[2] = {0xffff,0xffff};\r
+\r
+static struct arp_entry arp_table[UIP_ARPTAB_SIZE];\r
+static uip_ipaddr_t ipaddr;\r
+static u8_t i, c;\r
+\r
+static u8_t arptime;\r
+static u8_t tmpage;\r
+\r
+#define BUF ((struct arp_hdr *)&uip_buf[0])\r
+#define IPBUF ((struct ethip_hdr *)&uip_buf[0])\r
+\r
+#define DEBUG 0\r
+#if DEBUG\r
+#include <stdio.h>\r
+#define PRINTF(...) printf(__VA_ARGS__)\r
+#else\r
+#define PRINTF(...)\r
+#endif\r
+\r
+/*-----------------------------------------------------------------------------------*/\r
+/**\r
+ * Initialize the ARP module.\r
+ *\r
+ */\r
+/*-----------------------------------------------------------------------------------*/\r
+void\r
+uip_arp_init(void)\r
+{\r
+ for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {\r
+ memset(&arp_table[i].ipaddr, 0, 4);\r
+ }\r
+}\r
+/*-----------------------------------------------------------------------------------*/\r
+/**\r
+ * Periodic ARP processing function.\r
+ *\r
+ * This function performs periodic timer processing in the ARP module\r
+ * and should be called at regular intervals. The recommended interval\r
+ * is 10 seconds between the calls.\r
+ *\r
+ */\r
+/*-----------------------------------------------------------------------------------*/\r
+void\r
+uip_arp_timer(void)\r
+{\r
+ struct arp_entry *tabptr = NULL;\r
+ \r
+ ++arptime;\r
+ for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {\r
+ tabptr = &arp_table[i];\r
+ if(uip_ipaddr_cmp(&tabptr->ipaddr, &uip_all_zeroes_addr) &&\r
+ arptime - tabptr->time >= UIP_ARP_MAXAGE) {\r
+ memset(&tabptr->ipaddr, 0, 4);\r
+ }\r
+ }\r
+\r
+}\r
+/*-----------------------------------------------------------------------------------*/\r
+static void\r
+uip_arp_update(uip_ipaddr_t *ipaddr, struct uip_eth_addr *ethaddr)\r
+{\r
+ register struct arp_entry *tabptr = NULL;\r
+ /* Walk through the ARP mapping table and try to find an entry to\r
+ update. If none is found, the IP -> MAC address mapping is\r
+ inserted in the ARP table. */\r
+ for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {\r
+\r
+ tabptr = &arp_table[i];\r
+ /* Only check those entries that are actually in use. */\r
+ if(!uip_ipaddr_cmp(&tabptr->ipaddr, &uip_all_zeroes_addr)) {\r
+\r
+ /* Check if the source IP address of the incoming packet matches\r
+ the IP address in this ARP table entry. */\r
+ if(uip_ipaddr_cmp(ipaddr, &tabptr->ipaddr)) {\r
+ \r
+ /* An old entry found, update this and return. */\r
+ memcpy(tabptr->ethaddr.addr, ethaddr->addr, 6);\r
+ tabptr->time = arptime;\r
+\r
+ return;\r
+ }\r
+ }\r
+ }\r
+\r
+ /* If we get here, no existing ARP table entry was found, so we\r
+ create one. */\r
+\r
+ /* First, we try to find an unused entry in the ARP table. */\r
+ for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {\r
+ tabptr = &arp_table[i];\r
+ if(uip_ipaddr_cmp(&tabptr->ipaddr, &uip_all_zeroes_addr)) {\r
+ break;\r
+ }\r
+ }\r
+\r
+ /* If no unused entry is found, we try to find the oldest entry and\r
+ throw it away. */\r
+ if(i == UIP_ARPTAB_SIZE) {\r
+ tmpage = 0;\r
+ c = 0;\r
+ for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {\r
+ tabptr = &arp_table[i];\r
+ if(arptime - tabptr->time > tmpage) {\r
+ tmpage = arptime - tabptr->time;\r
+ c = i;\r
+ }\r
+ }\r
+ i = c;\r
+ tabptr = &arp_table[i];\r
+ }\r
+\r
+ /* Now, i is the ARP table entry which we will fill with the new\r
+ information. */\r
+ uip_ipaddr_copy(&tabptr->ipaddr, ipaddr);\r
+ memcpy(tabptr->ethaddr.addr, ethaddr->addr, 6);\r
+ tabptr->time = arptime;\r
+}\r
+/*-----------------------------------------------------------------------------------*/\r
+/**\r
+ * ARP processing for incoming IP packets\r
+ *\r
+ * This function should be called by the device driver when an IP\r
+ * packet has been received. The function will check if the address is\r
+ * in the ARP cache, and if so the ARP cache entry will be\r
+ * refreshed. If no ARP cache entry was found, a new one is created.\r
+ *\r
+ * This function expects an IP packet with a prepended Ethernet header\r
+ * in the uip_buf[] buffer, and the length of the packet in the global\r
+ * variable uip_len.\r
+ */\r
+/*-----------------------------------------------------------------------------------*/\r
+#if 0\r
+void\r
+uip_arp_ipin(void)\r
+{\r
+ uip_len -= sizeof(struct uip_eth_hdr);\r
+ \r
+ /* Only insert/update an entry if the source IP address of the\r
+ incoming IP packet comes from a host on the local network. */\r
+ if((IPBUF->srcipaddr[0] & uip_netmask[0]) !=\r
+ (uip_hostaddr[0] & uip_netmask[0])) {\r
+ return;\r
+ }\r
+ if((IPBUF->srcipaddr[1] & uip_netmask[1]) !=\r
+ (uip_hostaddr[1] & uip_netmask[1])) {\r
+ return;\r
+ }\r
+ uip_arp_update(IPBUF->srcipaddr, &(IPBUF->ethhdr.src));\r
+ \r
+ return;\r
+}\r
+#endif /* 0 */\r
+/*-----------------------------------------------------------------------------------*/\r
+/**\r
+ * ARP processing for incoming ARP packets.\r
+ *\r
+ * This function should be called by the device driver when an ARP\r
+ * packet has been received. The function will act differently\r
+ * depending on the ARP packet type: if it is a reply for a request\r
+ * that we previously sent out, the ARP cache will be filled in with\r
+ * the values from the ARP reply. If the incoming ARP packet is an ARP\r
+ * request for our IP address, an ARP reply packet is created and put\r
+ * into the uip_buf[] buffer.\r
+ *\r
+ * When the function returns, the value of the global variable uip_len\r
+ * indicates whether the device driver should send out a packet or\r
+ * not. If uip_len is zero, no packet should be sent. If uip_len is\r
+ * non-zero, it contains the length of the outbound packet that is\r
+ * present in the uip_buf[] buffer.\r
+ *\r
+ * This function expects an ARP packet with a prepended Ethernet\r
+ * header in the uip_buf[] buffer, and the length of the packet in the\r
+ * global variable uip_len.\r
+ */\r
+/*-----------------------------------------------------------------------------------*/\r
+void\r
+uip_arp_arpin(void)\r
+{\r
+ if(uip_len < sizeof(struct arp_hdr)) {\r
+ uip_len = 0;\r
+ return;\r
+ }\r
+ uip_len = 0;\r
+ \r
+ switch(BUF->opcode) {\r
+ case HTONS(ARP_REQUEST):\r
+ /* ARP request. If it asked for our address, we send out a\r
+ reply. */\r
+ /* if(BUF->dipaddr[0] == uip_hostaddr[0] &&\r
+ BUF->dipaddr[1] == uip_hostaddr[1]) {*/\r
+ PRINTF("uip_arp_arpin: request for %d.%d.%d.%d (we are %d.%d.%d.%d)\n",\r
+ BUF->dipaddr.u8[0], BUF->dipaddr.u8[1],\r
+ BUF->dipaddr.u8[2], BUF->dipaddr.u8[3],\r
+ uip_hostaddr.u8[0], uip_hostaddr.u8[1],\r
+ uip_hostaddr.u8[2], uip_hostaddr.u8[3]);\r
+ if(uip_ipaddr_cmp(&BUF->dipaddr, &uip_hostaddr)) {\r
+ /* First, we register the one who made the request in our ARP\r
+ table, since it is likely that we will do more communication\r
+ with this host in the future. */\r
+ uip_arp_update(&BUF->sipaddr, &BUF->shwaddr);\r
+ \r
+ BUF->opcode = HTONS(ARP_REPLY);\r
+\r
+ memcpy(BUF->dhwaddr.addr, BUF->shwaddr.addr, 6);\r
+ memcpy(BUF->shwaddr.addr, uip_ethaddr.addr, 6);\r
+ memcpy(BUF->ethhdr.src.addr, uip_ethaddr.addr, 6);\r
+ memcpy(BUF->ethhdr.dest.addr, BUF->dhwaddr.addr, 6);\r
+ \r
+ uip_ipaddr_copy(&BUF->dipaddr, &BUF->sipaddr);\r
+ uip_ipaddr_copy(&BUF->sipaddr, &uip_hostaddr);\r
+\r
+ BUF->ethhdr.type = HTONS(UIP_ETHTYPE_ARP);\r
+ uip_len = sizeof(struct arp_hdr);\r
+ }\r
+ break;\r
+ case HTONS(ARP_REPLY):\r
+ /* ARP reply. We insert or update the ARP table if it was meant\r
+ for us. */\r
+ if(uip_ipaddr_cmp(&BUF->dipaddr, &uip_hostaddr)) {\r
+ uip_arp_update(&BUF->sipaddr, &BUF->shwaddr);\r
+ }\r
+ break;\r
+ }\r
+\r
+ return;\r
+}\r
+/*-----------------------------------------------------------------------------------*/\r
+/**\r
+ * Prepend Ethernet header to an outbound IP packet and see if we need\r
+ * to send out an ARP request.\r
+ *\r
+ * This function should be called before sending out an IP packet. The\r
+ * function checks the destination IP address of the IP packet to see\r
+ * what Ethernet MAC address that should be used as a destination MAC\r
+ * address on the Ethernet.\r
+ *\r
+ * If the destination IP address is in the local network (determined\r
+ * by logical ANDing of netmask and our IP address), the function\r
+ * checks the ARP cache to see if an entry for the destination IP\r
+ * address is found. If so, an Ethernet header is prepended and the\r
+ * function returns. If no ARP cache entry is found for the\r
+ * destination IP address, the packet in the uip_buf[] is replaced by\r
+ * an ARP request packet for the IP address. The IP packet is dropped\r
+ * and it is assumed that they higher level protocols (e.g., TCP)\r
+ * eventually will retransmit the dropped packet.\r
+ *\r
+ * If the destination IP address is not on the local network, the IP\r
+ * address of the default router is used instead.\r
+ *\r
+ * When the function returns, a packet is present in the uip_buf[]\r
+ * buffer, and the length of the packet is in the global variable\r
+ * uip_len.\r
+ */\r
+/*-----------------------------------------------------------------------------------*/\r
+void\r
+uip_arp_out(void)\r
+{\r
+ struct arp_entry *tabptr = NULL;\r
+ \r
+ /* Find the destination IP address in the ARP table and construct\r
+ the Ethernet header. If the destination IP addres isn't on the\r
+ local network, we use the default router's IP address instead.\r
+\r
+ If not ARP table entry is found, we overwrite the original IP\r
+ packet with an ARP request for the IP address. */\r
+\r
+ /* First check if destination is a local broadcast. */\r
+ if(uip_ipaddr_cmp(&IPBUF->destipaddr, &uip_broadcast_addr)) {\r
+ memcpy(IPBUF->ethhdr.dest.addr, broadcast_ethaddr.addr, 6);\r
+ } else {\r
+ /* Check if the destination address is on the local network. */\r
+ if(!uip_ipaddr_maskcmp(&IPBUF->destipaddr, &uip_hostaddr, &uip_netmask)) {\r
+ /* Destination address was not on the local network, so we need to\r
+ use the default router's IP address instead of the destination\r
+ address when determining the MAC address. */\r
+ uip_ipaddr_copy(&ipaddr, &uip_draddr);\r
+ } else {\r
+ /* Else, we use the destination IP address. */\r
+ uip_ipaddr_copy(&ipaddr, &IPBUF->destipaddr);\r
+ }\r
+ \r
+ for(i = 0; i < UIP_ARPTAB_SIZE; ++i) {\r
+ tabptr = &arp_table[i];\r
+ if(uip_ipaddr_cmp(&ipaddr, &tabptr->ipaddr)) {\r
+ break;\r
+ }\r
+ }\r
+\r
+ if(i == UIP_ARPTAB_SIZE) {\r
+ /* The destination address was not in our ARP table, so we\r
+ overwrite the IP packet with an ARP request. */\r
+\r
+ memset(BUF->ethhdr.dest.addr, 0xff, 6);\r
+ memset(BUF->dhwaddr.addr, 0x00, 6);\r
+ memcpy(BUF->ethhdr.src.addr, uip_ethaddr.addr, 6);\r
+ memcpy(BUF->shwaddr.addr, uip_ethaddr.addr, 6);\r
+ \r
+ uip_ipaddr_copy(&BUF->dipaddr, &ipaddr);\r
+ uip_ipaddr_copy(&BUF->sipaddr, &uip_hostaddr);\r
+ BUF->opcode = HTONS(ARP_REQUEST); /* ARP request. */\r
+ BUF->hwtype = HTONS(ARP_HWTYPE_ETH);\r
+ BUF->protocol = HTONS(UIP_ETHTYPE_IP);\r
+ BUF->hwlen = 6;\r
+ BUF->protolen = 4;\r
+ BUF->ethhdr.type = HTONS(UIP_ETHTYPE_ARP);\r
+\r
+ uip_appdata = &uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN];\r
+ \r
+ uip_len = sizeof(struct arp_hdr);\r
+ return;\r
+ }\r
+\r
+ /* Build an ethernet header. */\r
+ memcpy(IPBUF->ethhdr.dest.addr, tabptr->ethaddr.addr, 6);\r
+ }\r
+ memcpy(IPBUF->ethhdr.src.addr, uip_ethaddr.addr, 6);\r
+ \r
+ IPBUF->ethhdr.type = HTONS(UIP_ETHTYPE_IP);\r
+\r
+ uip_len += sizeof(struct uip_eth_hdr);\r
+}\r
+/*-----------------------------------------------------------------------------------*/\r
+\r
+/** @} */\r
+/** @} */\r
projects / pub / lufa.git / blobdiff