diff options
Diffstat (limited to 'Projects/Webserver/Lib/uip/uip_arp.c')
-rw-r--r-- | Projects/Webserver/Lib/uip/uip_arp.c | 862 |
1 files changed, 431 insertions, 431 deletions
diff --git a/Projects/Webserver/Lib/uip/uip_arp.c b/Projects/Webserver/Lib/uip/uip_arp.c index 56dff9c43..88c14cc01 100644 --- a/Projects/Webserver/Lib/uip/uip_arp.c +++ b/Projects/Webserver/Lib/uip/uip_arp.c @@ -1,431 +1,431 @@ -/** - * \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); -} -/*-----------------------------------------------------------------------------------*/ - -/** @} */ -/** @} */ +/**
+ * \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);
+}
+/*-----------------------------------------------------------------------------------*/
+
+/** @} */
+/** @} */
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