Frank 26080115
These are the examples provided for [[/users/frank26080115/libraries/LPC1700CMSIS_Lib/]] Note, the entire "program" is not compilable!
EMAC/uIP/uip/uip_arp.c@0:bf7b9fba3924, 2011-03-20 (annotated)
- Committer:
- frank26080115
- Date:
- Sun Mar 20 05:38:56 2011 +0000
- Revision:
- 0:bf7b9fba3924
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| frank26080115 | 0:bf7b9fba3924 | 1 | /** |
| frank26080115 | 0:bf7b9fba3924 | 2 | * \addtogroup uip |
| frank26080115 | 0:bf7b9fba3924 | 3 | * @{ |
| frank26080115 | 0:bf7b9fba3924 | 4 | */ |
| frank26080115 | 0:bf7b9fba3924 | 5 | |
| frank26080115 | 0:bf7b9fba3924 | 6 | /** |
| frank26080115 | 0:bf7b9fba3924 | 7 | * \defgroup uiparp uIP Address Resolution Protocol |
| frank26080115 | 0:bf7b9fba3924 | 8 | * @{ |
| frank26080115 | 0:bf7b9fba3924 | 9 | * |
| frank26080115 | 0:bf7b9fba3924 | 10 | * The Address Resolution Protocol ARP is used for mapping between IP |
| frank26080115 | 0:bf7b9fba3924 | 11 | * addresses and link level addresses such as the Ethernet MAC |
| frank26080115 | 0:bf7b9fba3924 | 12 | * addresses. ARP uses broadcast queries to ask for the link level |
| frank26080115 | 0:bf7b9fba3924 | 13 | * address of a known IP address and the host which is configured with |
| frank26080115 | 0:bf7b9fba3924 | 14 | * the IP address for which the query was meant, will respond with its |
| frank26080115 | 0:bf7b9fba3924 | 15 | * link level address. |
| frank26080115 | 0:bf7b9fba3924 | 16 | * |
| frank26080115 | 0:bf7b9fba3924 | 17 | * \note This ARP implementation only supports Ethernet. |
| frank26080115 | 0:bf7b9fba3924 | 18 | */ |
| frank26080115 | 0:bf7b9fba3924 | 19 | |
| frank26080115 | 0:bf7b9fba3924 | 20 | /** |
| frank26080115 | 0:bf7b9fba3924 | 21 | * \file |
| frank26080115 | 0:bf7b9fba3924 | 22 | * Implementation of the ARP Address Resolution Protocol. |
| frank26080115 | 0:bf7b9fba3924 | 23 | * \author Adam Dunkels <adam@dunkels.com> |
| frank26080115 | 0:bf7b9fba3924 | 24 | * |
| frank26080115 | 0:bf7b9fba3924 | 25 | */ |
| frank26080115 | 0:bf7b9fba3924 | 26 | |
| frank26080115 | 0:bf7b9fba3924 | 27 | /* |
| frank26080115 | 0:bf7b9fba3924 | 28 | * Copyright (c) 2001-2003, Adam Dunkels. |
| frank26080115 | 0:bf7b9fba3924 | 29 | * All rights reserved. |
| frank26080115 | 0:bf7b9fba3924 | 30 | * |
| frank26080115 | 0:bf7b9fba3924 | 31 | * Redistribution and use in source and binary forms, with or without |
| frank26080115 | 0:bf7b9fba3924 | 32 | * modification, are permitted provided that the following conditions |
| frank26080115 | 0:bf7b9fba3924 | 33 | * are met: |
| frank26080115 | 0:bf7b9fba3924 | 34 | * 1. Redistributions of source code must retain the above copyright |
| frank26080115 | 0:bf7b9fba3924 | 35 | * notice, this list of conditions and the following disclaimer. |
| frank26080115 | 0:bf7b9fba3924 | 36 | * 2. Redistributions in binary form must reproduce the above copyright |
| frank26080115 | 0:bf7b9fba3924 | 37 | * notice, this list of conditions and the following disclaimer in the |
| frank26080115 | 0:bf7b9fba3924 | 38 | * documentation and/or other materials provided with the distribution. |
| frank26080115 | 0:bf7b9fba3924 | 39 | * 3. The name of the author may not be used to endorse or promote |
| frank26080115 | 0:bf7b9fba3924 | 40 | * products derived from this software without specific prior |
| frank26080115 | 0:bf7b9fba3924 | 41 | * written permission. |
| frank26080115 | 0:bf7b9fba3924 | 42 | * |
| frank26080115 | 0:bf7b9fba3924 | 43 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS |
| frank26080115 | 0:bf7b9fba3924 | 44 | * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
| frank26080115 | 0:bf7b9fba3924 | 45 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| frank26080115 | 0:bf7b9fba3924 | 46 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY |
| frank26080115 | 0:bf7b9fba3924 | 47 | * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| frank26080115 | 0:bf7b9fba3924 | 48 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE |
| frank26080115 | 0:bf7b9fba3924 | 49 | * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| frank26080115 | 0:bf7b9fba3924 | 50 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| frank26080115 | 0:bf7b9fba3924 | 51 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| frank26080115 | 0:bf7b9fba3924 | 52 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| frank26080115 | 0:bf7b9fba3924 | 53 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| frank26080115 | 0:bf7b9fba3924 | 54 | * |
| frank26080115 | 0:bf7b9fba3924 | 55 | * This file is part of the uIP TCP/IP stack. |
| frank26080115 | 0:bf7b9fba3924 | 56 | * |
| frank26080115 | 0:bf7b9fba3924 | 57 | * $Id: uip_arp.c,v 1.8 2006/06/02 23:36:21 adam Exp $ |
| frank26080115 | 0:bf7b9fba3924 | 58 | * |
| frank26080115 | 0:bf7b9fba3924 | 59 | */ |
| frank26080115 | 0:bf7b9fba3924 | 60 | |
| frank26080115 | 0:bf7b9fba3924 | 61 | |
| frank26080115 | 0:bf7b9fba3924 | 62 | #include "uip_arp.h" |
| frank26080115 | 0:bf7b9fba3924 | 63 | |
| frank26080115 | 0:bf7b9fba3924 | 64 | #include <string.h> |
| frank26080115 | 0:bf7b9fba3924 | 65 | |
| frank26080115 | 0:bf7b9fba3924 | 66 | #ifdef __ICCARM__ |
| frank26080115 | 0:bf7b9fba3924 | 67 | #pragma pack(1) |
| frank26080115 | 0:bf7b9fba3924 | 68 | #endif |
| frank26080115 | 0:bf7b9fba3924 | 69 | |
| frank26080115 | 0:bf7b9fba3924 | 70 | //#if defined ( __CC_ARM ) |
| frank26080115 | 0:bf7b9fba3924 | 71 | //__packed |
| frank26080115 | 0:bf7b9fba3924 | 72 | //#elif defined ( __GNUC__ ) |
| frank26080115 | 0:bf7b9fba3924 | 73 | //__attribute__ ((__packed__)) |
| frank26080115 | 0:bf7b9fba3924 | 74 | //#endif |
| frank26080115 | 0:bf7b9fba3924 | 75 | struct arp_hdr { |
| frank26080115 | 0:bf7b9fba3924 | 76 | struct uip_eth_hdr ethhdr; |
| frank26080115 | 0:bf7b9fba3924 | 77 | u16_t hwtype; |
| frank26080115 | 0:bf7b9fba3924 | 78 | u16_t protocol; |
| frank26080115 | 0:bf7b9fba3924 | 79 | u8_t hwlen; |
| frank26080115 | 0:bf7b9fba3924 | 80 | u8_t protolen; |
| frank26080115 | 0:bf7b9fba3924 | 81 | u16_t opcode; |
| frank26080115 | 0:bf7b9fba3924 | 82 | struct uip_eth_addr shwaddr; |
| frank26080115 | 0:bf7b9fba3924 | 83 | u16_t sipaddr[2]; |
| frank26080115 | 0:bf7b9fba3924 | 84 | struct uip_eth_addr dhwaddr; |
| frank26080115 | 0:bf7b9fba3924 | 85 | u16_t dipaddr[2]; |
| frank26080115 | 0:bf7b9fba3924 | 86 | } /*PACK_STRUCT_END*/; |
| frank26080115 | 0:bf7b9fba3924 | 87 | |
| frank26080115 | 0:bf7b9fba3924 | 88 | #ifdef __ICCARM__ |
| frank26080115 | 0:bf7b9fba3924 | 89 | #pragma pack() |
| frank26080115 | 0:bf7b9fba3924 | 90 | #endif |
| frank26080115 | 0:bf7b9fba3924 | 91 | |
| frank26080115 | 0:bf7b9fba3924 | 92 | #ifdef __ICCARM__ |
| frank26080115 | 0:bf7b9fba3924 | 93 | #pragma pack(1) |
| frank26080115 | 0:bf7b9fba3924 | 94 | #endif |
| frank26080115 | 0:bf7b9fba3924 | 95 | |
| frank26080115 | 0:bf7b9fba3924 | 96 | //#if defined ( __CC_ARM ) |
| frank26080115 | 0:bf7b9fba3924 | 97 | //__packed |
| frank26080115 | 0:bf7b9fba3924 | 98 | //#elif defined ( __GNUC__ ) |
| frank26080115 | 0:bf7b9fba3924 | 99 | //__attribute__ ((__packed__)) |
| frank26080115 | 0:bf7b9fba3924 | 100 | //#endif |
| frank26080115 | 0:bf7b9fba3924 | 101 | struct ethip_hdr { |
| frank26080115 | 0:bf7b9fba3924 | 102 | struct uip_eth_hdr ethhdr; |
| frank26080115 | 0:bf7b9fba3924 | 103 | /* IP header. */ |
| frank26080115 | 0:bf7b9fba3924 | 104 | u8_t vhl, |
| frank26080115 | 0:bf7b9fba3924 | 105 | tos, |
| frank26080115 | 0:bf7b9fba3924 | 106 | len[2], |
| frank26080115 | 0:bf7b9fba3924 | 107 | ipid[2], |
| frank26080115 | 0:bf7b9fba3924 | 108 | ipoffset[2], |
| frank26080115 | 0:bf7b9fba3924 | 109 | ttl, |
| frank26080115 | 0:bf7b9fba3924 | 110 | proto; |
| frank26080115 | 0:bf7b9fba3924 | 111 | u16_t ipchksum; |
| frank26080115 | 0:bf7b9fba3924 | 112 | u16_t srcipaddr[2], |
| frank26080115 | 0:bf7b9fba3924 | 113 | destipaddr[2]; |
| frank26080115 | 0:bf7b9fba3924 | 114 | } /*PACK_STRUCT_END*/; |
| frank26080115 | 0:bf7b9fba3924 | 115 | |
| frank26080115 | 0:bf7b9fba3924 | 116 | #ifdef __ICCARM__ |
| frank26080115 | 0:bf7b9fba3924 | 117 | #pragma pack() |
| frank26080115 | 0:bf7b9fba3924 | 118 | #endif |
| frank26080115 | 0:bf7b9fba3924 | 119 | |
| frank26080115 | 0:bf7b9fba3924 | 120 | #define ARP_REQUEST 1 |
| frank26080115 | 0:bf7b9fba3924 | 121 | #define ARP_REPLY 2 |
| frank26080115 | 0:bf7b9fba3924 | 122 | |
| frank26080115 | 0:bf7b9fba3924 | 123 | #define ARP_HWTYPE_ETH 1 |
| frank26080115 | 0:bf7b9fba3924 | 124 | |
| frank26080115 | 0:bf7b9fba3924 | 125 | struct arp_entry { |
| frank26080115 | 0:bf7b9fba3924 | 126 | u16_t ipaddr[2]; |
| frank26080115 | 0:bf7b9fba3924 | 127 | struct uip_eth_addr ethaddr; |
| frank26080115 | 0:bf7b9fba3924 | 128 | u8_t time; |
| frank26080115 | 0:bf7b9fba3924 | 129 | }; |
| frank26080115 | 0:bf7b9fba3924 | 130 | |
| frank26080115 | 0:bf7b9fba3924 | 131 | static const struct uip_eth_addr broadcast_ethaddr = |
| frank26080115 | 0:bf7b9fba3924 | 132 | {{0xff,0xff,0xff,0xff,0xff,0xff}}; |
| frank26080115 | 0:bf7b9fba3924 | 133 | static const u16_t broadcast_ipaddr[2] = {0xffff,0xffff}; |
| frank26080115 | 0:bf7b9fba3924 | 134 | |
| frank26080115 | 0:bf7b9fba3924 | 135 | static struct arp_entry arp_table[UIP_ARPTAB_SIZE]; |
| frank26080115 | 0:bf7b9fba3924 | 136 | static u16_t ipaddr[2]; |
| frank26080115 | 0:bf7b9fba3924 | 137 | static u8_t i, c; |
| frank26080115 | 0:bf7b9fba3924 | 138 | |
| frank26080115 | 0:bf7b9fba3924 | 139 | static u8_t arptime; |
| frank26080115 | 0:bf7b9fba3924 | 140 | static u8_t tmpage; |
| frank26080115 | 0:bf7b9fba3924 | 141 | |
| frank26080115 | 0:bf7b9fba3924 | 142 | #define BUF ((struct arp_hdr *)&uip_buf[0]) |
| frank26080115 | 0:bf7b9fba3924 | 143 | #define IPBUF ((struct ethip_hdr *)&uip_buf[0]) |
| frank26080115 | 0:bf7b9fba3924 | 144 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 145 | /** |
| frank26080115 | 0:bf7b9fba3924 | 146 | * Initialize the ARP module. |
| frank26080115 | 0:bf7b9fba3924 | 147 | * |
| frank26080115 | 0:bf7b9fba3924 | 148 | */ |
| frank26080115 | 0:bf7b9fba3924 | 149 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 150 | void |
| frank26080115 | 0:bf7b9fba3924 | 151 | uip_arp_init(void) |
| frank26080115 | 0:bf7b9fba3924 | 152 | { |
| frank26080115 | 0:bf7b9fba3924 | 153 | for(i = 0; i < UIP_ARPTAB_SIZE; ++i) { |
| frank26080115 | 0:bf7b9fba3924 | 154 | memset(arp_table[i].ipaddr, 0, 4); |
| frank26080115 | 0:bf7b9fba3924 | 155 | } |
| frank26080115 | 0:bf7b9fba3924 | 156 | } |
| frank26080115 | 0:bf7b9fba3924 | 157 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 158 | /** |
| frank26080115 | 0:bf7b9fba3924 | 159 | * Periodic ARP processing function. |
| frank26080115 | 0:bf7b9fba3924 | 160 | * |
| frank26080115 | 0:bf7b9fba3924 | 161 | * This function performs periodic timer processing in the ARP module |
| frank26080115 | 0:bf7b9fba3924 | 162 | * and should be called at regular intervals. The recommended interval |
| frank26080115 | 0:bf7b9fba3924 | 163 | * is 10 seconds between the calls. |
| frank26080115 | 0:bf7b9fba3924 | 164 | * |
| frank26080115 | 0:bf7b9fba3924 | 165 | */ |
| frank26080115 | 0:bf7b9fba3924 | 166 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 167 | void |
| frank26080115 | 0:bf7b9fba3924 | 168 | uip_arp_timer(void) |
| frank26080115 | 0:bf7b9fba3924 | 169 | { |
| frank26080115 | 0:bf7b9fba3924 | 170 | struct arp_entry *tabptr; |
| frank26080115 | 0:bf7b9fba3924 | 171 | |
| frank26080115 | 0:bf7b9fba3924 | 172 | ++arptime; |
| frank26080115 | 0:bf7b9fba3924 | 173 | for(i = 0; i < UIP_ARPTAB_SIZE; ++i) { |
| frank26080115 | 0:bf7b9fba3924 | 174 | tabptr = &arp_table[i]; |
| frank26080115 | 0:bf7b9fba3924 | 175 | if((tabptr->ipaddr[0] | tabptr->ipaddr[1]) != 0 && |
| frank26080115 | 0:bf7b9fba3924 | 176 | arptime - tabptr->time >= UIP_ARP_MAXAGE) { |
| frank26080115 | 0:bf7b9fba3924 | 177 | memset(tabptr->ipaddr, 0, 4); |
| frank26080115 | 0:bf7b9fba3924 | 178 | } |
| frank26080115 | 0:bf7b9fba3924 | 179 | } |
| frank26080115 | 0:bf7b9fba3924 | 180 | |
| frank26080115 | 0:bf7b9fba3924 | 181 | } |
| frank26080115 | 0:bf7b9fba3924 | 182 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 183 | static void |
| frank26080115 | 0:bf7b9fba3924 | 184 | uip_arp_update(u16_t *ipaddr, struct uip_eth_addr *ethaddr) |
| frank26080115 | 0:bf7b9fba3924 | 185 | { |
| frank26080115 | 0:bf7b9fba3924 | 186 | register struct arp_entry *tabptr; |
| frank26080115 | 0:bf7b9fba3924 | 187 | /* Walk through the ARP mapping table and try to find an entry to |
| frank26080115 | 0:bf7b9fba3924 | 188 | update. If none is found, the IP -> MAC address mapping is |
| frank26080115 | 0:bf7b9fba3924 | 189 | inserted in the ARP table. */ |
| frank26080115 | 0:bf7b9fba3924 | 190 | for(i = 0; i < UIP_ARPTAB_SIZE; ++i) { |
| frank26080115 | 0:bf7b9fba3924 | 191 | |
| frank26080115 | 0:bf7b9fba3924 | 192 | tabptr = &arp_table[i]; |
| frank26080115 | 0:bf7b9fba3924 | 193 | /* Only check those entries that are actually in use. */ |
| frank26080115 | 0:bf7b9fba3924 | 194 | if(tabptr->ipaddr[0] != 0 && |
| frank26080115 | 0:bf7b9fba3924 | 195 | tabptr->ipaddr[1] != 0) { |
| frank26080115 | 0:bf7b9fba3924 | 196 | |
| frank26080115 | 0:bf7b9fba3924 | 197 | /* Check if the source IP address of the incoming packet matches |
| frank26080115 | 0:bf7b9fba3924 | 198 | the IP address in this ARP table entry. */ |
| frank26080115 | 0:bf7b9fba3924 | 199 | if(ipaddr[0] == tabptr->ipaddr[0] && |
| frank26080115 | 0:bf7b9fba3924 | 200 | ipaddr[1] == tabptr->ipaddr[1]) { |
| frank26080115 | 0:bf7b9fba3924 | 201 | |
| frank26080115 | 0:bf7b9fba3924 | 202 | /* An old entry found, update this and return. */ |
| frank26080115 | 0:bf7b9fba3924 | 203 | memcpy(tabptr->ethaddr.addr, ethaddr->addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 204 | tabptr->time = arptime; |
| frank26080115 | 0:bf7b9fba3924 | 205 | |
| frank26080115 | 0:bf7b9fba3924 | 206 | return; |
| frank26080115 | 0:bf7b9fba3924 | 207 | } |
| frank26080115 | 0:bf7b9fba3924 | 208 | } |
| frank26080115 | 0:bf7b9fba3924 | 209 | } |
| frank26080115 | 0:bf7b9fba3924 | 210 | |
| frank26080115 | 0:bf7b9fba3924 | 211 | /* If we get here, no existing ARP table entry was found, so we |
| frank26080115 | 0:bf7b9fba3924 | 212 | create one. */ |
| frank26080115 | 0:bf7b9fba3924 | 213 | |
| frank26080115 | 0:bf7b9fba3924 | 214 | /* First, we try to find an unused entry in the ARP table. */ |
| frank26080115 | 0:bf7b9fba3924 | 215 | for(i = 0; i < UIP_ARPTAB_SIZE; ++i) { |
| frank26080115 | 0:bf7b9fba3924 | 216 | tabptr = &arp_table[i]; |
| frank26080115 | 0:bf7b9fba3924 | 217 | if(tabptr->ipaddr[0] == 0 && |
| frank26080115 | 0:bf7b9fba3924 | 218 | tabptr->ipaddr[1] == 0) { |
| frank26080115 | 0:bf7b9fba3924 | 219 | break; |
| frank26080115 | 0:bf7b9fba3924 | 220 | } |
| frank26080115 | 0:bf7b9fba3924 | 221 | } |
| frank26080115 | 0:bf7b9fba3924 | 222 | |
| frank26080115 | 0:bf7b9fba3924 | 223 | /* If no unused entry is found, we try to find the oldest entry and |
| frank26080115 | 0:bf7b9fba3924 | 224 | throw it away. */ |
| frank26080115 | 0:bf7b9fba3924 | 225 | if(i == UIP_ARPTAB_SIZE) { |
| frank26080115 | 0:bf7b9fba3924 | 226 | tmpage = 0; |
| frank26080115 | 0:bf7b9fba3924 | 227 | c = 0; |
| frank26080115 | 0:bf7b9fba3924 | 228 | for(i = 0; i < UIP_ARPTAB_SIZE; ++i) { |
| frank26080115 | 0:bf7b9fba3924 | 229 | tabptr = &arp_table[i]; |
| frank26080115 | 0:bf7b9fba3924 | 230 | if(arptime - tabptr->time > tmpage) { |
| frank26080115 | 0:bf7b9fba3924 | 231 | tmpage = arptime - tabptr->time; |
| frank26080115 | 0:bf7b9fba3924 | 232 | c = i; |
| frank26080115 | 0:bf7b9fba3924 | 233 | } |
| frank26080115 | 0:bf7b9fba3924 | 234 | } |
| frank26080115 | 0:bf7b9fba3924 | 235 | i = c; |
| frank26080115 | 0:bf7b9fba3924 | 236 | tabptr = &arp_table[i]; |
| frank26080115 | 0:bf7b9fba3924 | 237 | } |
| frank26080115 | 0:bf7b9fba3924 | 238 | |
| frank26080115 | 0:bf7b9fba3924 | 239 | /* Now, i is the ARP table entry which we will fill with the new |
| frank26080115 | 0:bf7b9fba3924 | 240 | information. */ |
| frank26080115 | 0:bf7b9fba3924 | 241 | memcpy(tabptr->ipaddr, ipaddr, 4); |
| frank26080115 | 0:bf7b9fba3924 | 242 | memcpy(tabptr->ethaddr.addr, ethaddr->addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 243 | tabptr->time = arptime; |
| frank26080115 | 0:bf7b9fba3924 | 244 | } |
| frank26080115 | 0:bf7b9fba3924 | 245 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 246 | /** |
| frank26080115 | 0:bf7b9fba3924 | 247 | * ARP processing for incoming IP packets |
| frank26080115 | 0:bf7b9fba3924 | 248 | * |
| frank26080115 | 0:bf7b9fba3924 | 249 | * This function should be called by the device driver when an IP |
| frank26080115 | 0:bf7b9fba3924 | 250 | * packet has been received. The function will check if the address is |
| frank26080115 | 0:bf7b9fba3924 | 251 | * in the ARP cache, and if so the ARP cache entry will be |
| frank26080115 | 0:bf7b9fba3924 | 252 | * refreshed. If no ARP cache entry was found, a new one is created. |
| frank26080115 | 0:bf7b9fba3924 | 253 | * |
| frank26080115 | 0:bf7b9fba3924 | 254 | * This function expects an IP packet with a prepended Ethernet header |
| frank26080115 | 0:bf7b9fba3924 | 255 | * in the uip_buf[] buffer, and the length of the packet in the global |
| frank26080115 | 0:bf7b9fba3924 | 256 | * variable uip_len. |
| frank26080115 | 0:bf7b9fba3924 | 257 | */ |
| frank26080115 | 0:bf7b9fba3924 | 258 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 259 | #if 1 |
| frank26080115 | 0:bf7b9fba3924 | 260 | void |
| frank26080115 | 0:bf7b9fba3924 | 261 | uip_arp_ipin(void) |
| frank26080115 | 0:bf7b9fba3924 | 262 | { |
| frank26080115 | 0:bf7b9fba3924 | 263 | uip_len -= sizeof(struct uip_eth_hdr); |
| frank26080115 | 0:bf7b9fba3924 | 264 | |
| frank26080115 | 0:bf7b9fba3924 | 265 | /* Only insert/update an entry if the source IP address of the |
| frank26080115 | 0:bf7b9fba3924 | 266 | incoming IP packet comes from a host on the local network. */ |
| frank26080115 | 0:bf7b9fba3924 | 267 | if((IPBUF->srcipaddr[0] & uip_netmask[0]) != |
| frank26080115 | 0:bf7b9fba3924 | 268 | (uip_hostaddr[0] & uip_netmask[0])) { |
| frank26080115 | 0:bf7b9fba3924 | 269 | return; |
| frank26080115 | 0:bf7b9fba3924 | 270 | } |
| frank26080115 | 0:bf7b9fba3924 | 271 | if((IPBUF->srcipaddr[1] & uip_netmask[1]) != |
| frank26080115 | 0:bf7b9fba3924 | 272 | (uip_hostaddr[1] & uip_netmask[1])) { |
| frank26080115 | 0:bf7b9fba3924 | 273 | return; |
| frank26080115 | 0:bf7b9fba3924 | 274 | } |
| frank26080115 | 0:bf7b9fba3924 | 275 | uip_arp_update(IPBUF->srcipaddr, &(IPBUF->ethhdr.src)); |
| frank26080115 | 0:bf7b9fba3924 | 276 | |
| frank26080115 | 0:bf7b9fba3924 | 277 | return; |
| frank26080115 | 0:bf7b9fba3924 | 278 | } |
| frank26080115 | 0:bf7b9fba3924 | 279 | #endif /* 0 */ |
| frank26080115 | 0:bf7b9fba3924 | 280 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 281 | /** |
| frank26080115 | 0:bf7b9fba3924 | 282 | * ARP processing for incoming ARP packets. |
| frank26080115 | 0:bf7b9fba3924 | 283 | * |
| frank26080115 | 0:bf7b9fba3924 | 284 | * This function should be called by the device driver when an ARP |
| frank26080115 | 0:bf7b9fba3924 | 285 | * packet has been received. The function will act differently |
| frank26080115 | 0:bf7b9fba3924 | 286 | * depending on the ARP packet type: if it is a reply for a request |
| frank26080115 | 0:bf7b9fba3924 | 287 | * that we previously sent out, the ARP cache will be filled in with |
| frank26080115 | 0:bf7b9fba3924 | 288 | * the values from the ARP reply. If the incoming ARP packet is an ARP |
| frank26080115 | 0:bf7b9fba3924 | 289 | * request for our IP address, an ARP reply packet is created and put |
| frank26080115 | 0:bf7b9fba3924 | 290 | * into the uip_buf[] buffer. |
| frank26080115 | 0:bf7b9fba3924 | 291 | * |
| frank26080115 | 0:bf7b9fba3924 | 292 | * When the function returns, the value of the global variable uip_len |
| frank26080115 | 0:bf7b9fba3924 | 293 | * indicates whether the device driver should send out a packet or |
| frank26080115 | 0:bf7b9fba3924 | 294 | * not. If uip_len is zero, no packet should be sent. If uip_len is |
| frank26080115 | 0:bf7b9fba3924 | 295 | * non-zero, it contains the length of the outbound packet that is |
| frank26080115 | 0:bf7b9fba3924 | 296 | * present in the uip_buf[] buffer. |
| frank26080115 | 0:bf7b9fba3924 | 297 | * |
| frank26080115 | 0:bf7b9fba3924 | 298 | * This function expects an ARP packet with a prepended Ethernet |
| frank26080115 | 0:bf7b9fba3924 | 299 | * header in the uip_buf[] buffer, and the length of the packet in the |
| frank26080115 | 0:bf7b9fba3924 | 300 | * global variable uip_len. |
| frank26080115 | 0:bf7b9fba3924 | 301 | */ |
| frank26080115 | 0:bf7b9fba3924 | 302 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 303 | void |
| frank26080115 | 0:bf7b9fba3924 | 304 | uip_arp_arpin(void) |
| frank26080115 | 0:bf7b9fba3924 | 305 | { |
| frank26080115 | 0:bf7b9fba3924 | 306 | |
| frank26080115 | 0:bf7b9fba3924 | 307 | if(uip_len < sizeof(struct arp_hdr)) { |
| frank26080115 | 0:bf7b9fba3924 | 308 | uip_len = 0; |
| frank26080115 | 0:bf7b9fba3924 | 309 | return; |
| frank26080115 | 0:bf7b9fba3924 | 310 | } |
| frank26080115 | 0:bf7b9fba3924 | 311 | uip_len = 0; |
| frank26080115 | 0:bf7b9fba3924 | 312 | |
| frank26080115 | 0:bf7b9fba3924 | 313 | switch(BUF->opcode) { |
| frank26080115 | 0:bf7b9fba3924 | 314 | case HTONS(ARP_REQUEST): |
| frank26080115 | 0:bf7b9fba3924 | 315 | /* ARP request. If it asked for our address, we send out a |
| frank26080115 | 0:bf7b9fba3924 | 316 | reply. */ |
| frank26080115 | 0:bf7b9fba3924 | 317 | if(uip_ipaddr_cmp(BUF->dipaddr, uip_hostaddr)) { |
| frank26080115 | 0:bf7b9fba3924 | 318 | /* First, we register the one who made the request in our ARP |
| frank26080115 | 0:bf7b9fba3924 | 319 | table, since it is likely that we will do more communication |
| frank26080115 | 0:bf7b9fba3924 | 320 | with this host in the future. */ |
| frank26080115 | 0:bf7b9fba3924 | 321 | uip_arp_update(BUF->sipaddr, &BUF->shwaddr); |
| frank26080115 | 0:bf7b9fba3924 | 322 | |
| frank26080115 | 0:bf7b9fba3924 | 323 | /* The reply opcode is 2. */ |
| frank26080115 | 0:bf7b9fba3924 | 324 | BUF->opcode = HTONS(2); |
| frank26080115 | 0:bf7b9fba3924 | 325 | |
| frank26080115 | 0:bf7b9fba3924 | 326 | memcpy(BUF->dhwaddr.addr, BUF->shwaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 327 | memcpy(BUF->shwaddr.addr, uip_ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 328 | memcpy(BUF->ethhdr.src.addr, uip_ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 329 | memcpy(BUF->ethhdr.dest.addr, BUF->dhwaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 330 | |
| frank26080115 | 0:bf7b9fba3924 | 331 | BUF->dipaddr[0] = BUF->sipaddr[0]; |
| frank26080115 | 0:bf7b9fba3924 | 332 | BUF->dipaddr[1] = BUF->sipaddr[1]; |
| frank26080115 | 0:bf7b9fba3924 | 333 | BUF->sipaddr[0] = uip_hostaddr[0]; |
| frank26080115 | 0:bf7b9fba3924 | 334 | BUF->sipaddr[1] = uip_hostaddr[1]; |
| frank26080115 | 0:bf7b9fba3924 | 335 | |
| frank26080115 | 0:bf7b9fba3924 | 336 | BUF->ethhdr.type = HTONS(UIP_ETHTYPE_ARP); |
| frank26080115 | 0:bf7b9fba3924 | 337 | uip_len = sizeof(struct arp_hdr); |
| frank26080115 | 0:bf7b9fba3924 | 338 | } |
| frank26080115 | 0:bf7b9fba3924 | 339 | break; |
| frank26080115 | 0:bf7b9fba3924 | 340 | case HTONS(ARP_REPLY): |
| frank26080115 | 0:bf7b9fba3924 | 341 | /* ARP reply. We insert or update the ARP table if it was meant |
| frank26080115 | 0:bf7b9fba3924 | 342 | for us. */ |
| frank26080115 | 0:bf7b9fba3924 | 343 | if(uip_ipaddr_cmp(BUF->dipaddr, uip_hostaddr)) { |
| frank26080115 | 0:bf7b9fba3924 | 344 | uip_arp_update(BUF->sipaddr, &BUF->shwaddr); |
| frank26080115 | 0:bf7b9fba3924 | 345 | } |
| frank26080115 | 0:bf7b9fba3924 | 346 | break; |
| frank26080115 | 0:bf7b9fba3924 | 347 | } |
| frank26080115 | 0:bf7b9fba3924 | 348 | |
| frank26080115 | 0:bf7b9fba3924 | 349 | return; |
| frank26080115 | 0:bf7b9fba3924 | 350 | } |
| frank26080115 | 0:bf7b9fba3924 | 351 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 352 | /** |
| frank26080115 | 0:bf7b9fba3924 | 353 | * Prepend Ethernet header to an outbound IP packet and see if we need |
| frank26080115 | 0:bf7b9fba3924 | 354 | * to send out an ARP request. |
| frank26080115 | 0:bf7b9fba3924 | 355 | * |
| frank26080115 | 0:bf7b9fba3924 | 356 | * This function should be called before sending out an IP packet. The |
| frank26080115 | 0:bf7b9fba3924 | 357 | * function checks the destination IP address of the IP packet to see |
| frank26080115 | 0:bf7b9fba3924 | 358 | * what Ethernet MAC address that should be used as a destination MAC |
| frank26080115 | 0:bf7b9fba3924 | 359 | * address on the Ethernet. |
| frank26080115 | 0:bf7b9fba3924 | 360 | * |
| frank26080115 | 0:bf7b9fba3924 | 361 | * If the destination IP address is in the local network (determined |
| frank26080115 | 0:bf7b9fba3924 | 362 | * by logical ANDing of netmask and our IP address), the function |
| frank26080115 | 0:bf7b9fba3924 | 363 | * checks the ARP cache to see if an entry for the destination IP |
| frank26080115 | 0:bf7b9fba3924 | 364 | * address is found. If so, an Ethernet header is prepended and the |
| frank26080115 | 0:bf7b9fba3924 | 365 | * function returns. If no ARP cache entry is found for the |
| frank26080115 | 0:bf7b9fba3924 | 366 | * destination IP address, the packet in the uip_buf[] is replaced by |
| frank26080115 | 0:bf7b9fba3924 | 367 | * an ARP request packet for the IP address. The IP packet is dropped |
| frank26080115 | 0:bf7b9fba3924 | 368 | * and it is assumed that they higher level protocols (e.g., TCP) |
| frank26080115 | 0:bf7b9fba3924 | 369 | * eventually will retransmit the dropped packet. |
| frank26080115 | 0:bf7b9fba3924 | 370 | * |
| frank26080115 | 0:bf7b9fba3924 | 371 | * If the destination IP address is not on the local network, the IP |
| frank26080115 | 0:bf7b9fba3924 | 372 | * address of the default router is used instead. |
| frank26080115 | 0:bf7b9fba3924 | 373 | * |
| frank26080115 | 0:bf7b9fba3924 | 374 | * When the function returns, a packet is present in the uip_buf[] |
| frank26080115 | 0:bf7b9fba3924 | 375 | * buffer, and the length of the packet is in the global variable |
| frank26080115 | 0:bf7b9fba3924 | 376 | * uip_len. |
| frank26080115 | 0:bf7b9fba3924 | 377 | */ |
| frank26080115 | 0:bf7b9fba3924 | 378 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 379 | void |
| frank26080115 | 0:bf7b9fba3924 | 380 | uip_arp_out(void) |
| frank26080115 | 0:bf7b9fba3924 | 381 | { |
| frank26080115 | 0:bf7b9fba3924 | 382 | struct arp_entry *tabptr; |
| frank26080115 | 0:bf7b9fba3924 | 383 | |
| frank26080115 | 0:bf7b9fba3924 | 384 | /* Find the destination IP address in the ARP table and construct |
| frank26080115 | 0:bf7b9fba3924 | 385 | the Ethernet header. If the destination IP addres isn't on the |
| frank26080115 | 0:bf7b9fba3924 | 386 | local network, we use the default router's IP address instead. |
| frank26080115 | 0:bf7b9fba3924 | 387 | |
| frank26080115 | 0:bf7b9fba3924 | 388 | If not ARP table entry is found, we overwrite the original IP |
| frank26080115 | 0:bf7b9fba3924 | 389 | packet with an ARP request for the IP address. */ |
| frank26080115 | 0:bf7b9fba3924 | 390 | |
| frank26080115 | 0:bf7b9fba3924 | 391 | /* First check if destination is a local broadcast. */ |
| frank26080115 | 0:bf7b9fba3924 | 392 | if(uip_ipaddr_cmp(IPBUF->destipaddr, broadcast_ipaddr)) { |
| frank26080115 | 0:bf7b9fba3924 | 393 | memcpy(IPBUF->ethhdr.dest.addr, broadcast_ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 394 | } else { |
| frank26080115 | 0:bf7b9fba3924 | 395 | /* Check if the destination address is on the local network. */ |
| frank26080115 | 0:bf7b9fba3924 | 396 | if(!uip_ipaddr_maskcmp(IPBUF->destipaddr, uip_hostaddr, uip_netmask)) { |
| frank26080115 | 0:bf7b9fba3924 | 397 | /* Destination address was not on the local network, so we need to |
| frank26080115 | 0:bf7b9fba3924 | 398 | use the default router's IP address instead of the destination |
| frank26080115 | 0:bf7b9fba3924 | 399 | address when determining the MAC address. */ |
| frank26080115 | 0:bf7b9fba3924 | 400 | uip_ipaddr_copy(ipaddr, uip_draddr); |
| frank26080115 | 0:bf7b9fba3924 | 401 | } else { |
| frank26080115 | 0:bf7b9fba3924 | 402 | /* Else, we use the destination IP address. */ |
| frank26080115 | 0:bf7b9fba3924 | 403 | uip_ipaddr_copy(ipaddr, IPBUF->destipaddr); |
| frank26080115 | 0:bf7b9fba3924 | 404 | } |
| frank26080115 | 0:bf7b9fba3924 | 405 | |
| frank26080115 | 0:bf7b9fba3924 | 406 | for(i = 0; i < UIP_ARPTAB_SIZE; ++i) { |
| frank26080115 | 0:bf7b9fba3924 | 407 | tabptr = &arp_table[i]; |
| frank26080115 | 0:bf7b9fba3924 | 408 | if(uip_ipaddr_cmp(ipaddr, tabptr->ipaddr)) { |
| frank26080115 | 0:bf7b9fba3924 | 409 | break; |
| frank26080115 | 0:bf7b9fba3924 | 410 | } |
| frank26080115 | 0:bf7b9fba3924 | 411 | } |
| frank26080115 | 0:bf7b9fba3924 | 412 | |
| frank26080115 | 0:bf7b9fba3924 | 413 | if(i == UIP_ARPTAB_SIZE) { |
| frank26080115 | 0:bf7b9fba3924 | 414 | /* The destination address was not in our ARP table, so we |
| frank26080115 | 0:bf7b9fba3924 | 415 | overwrite the IP packet with an ARP request. */ |
| frank26080115 | 0:bf7b9fba3924 | 416 | |
| frank26080115 | 0:bf7b9fba3924 | 417 | memset(BUF->ethhdr.dest.addr, 0xff, 6); |
| frank26080115 | 0:bf7b9fba3924 | 418 | memset(BUF->dhwaddr.addr, 0x00, 6); |
| frank26080115 | 0:bf7b9fba3924 | 419 | memcpy(BUF->ethhdr.src.addr, uip_ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 420 | memcpy(BUF->shwaddr.addr, uip_ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 421 | |
| frank26080115 | 0:bf7b9fba3924 | 422 | uip_ipaddr_copy(BUF->dipaddr, ipaddr); |
| frank26080115 | 0:bf7b9fba3924 | 423 | uip_ipaddr_copy(BUF->sipaddr, uip_hostaddr); |
| frank26080115 | 0:bf7b9fba3924 | 424 | BUF->opcode = HTONS(ARP_REQUEST); /* ARP request. */ |
| frank26080115 | 0:bf7b9fba3924 | 425 | BUF->hwtype = HTONS(ARP_HWTYPE_ETH); |
| frank26080115 | 0:bf7b9fba3924 | 426 | BUF->protocol = HTONS(UIP_ETHTYPE_IP); |
| frank26080115 | 0:bf7b9fba3924 | 427 | BUF->hwlen = 6; |
| frank26080115 | 0:bf7b9fba3924 | 428 | BUF->protolen = 4; |
| frank26080115 | 0:bf7b9fba3924 | 429 | BUF->ethhdr.type = HTONS(UIP_ETHTYPE_ARP); |
| frank26080115 | 0:bf7b9fba3924 | 430 | |
| frank26080115 | 0:bf7b9fba3924 | 431 | uip_appdata = &uip_buf[UIP_TCPIP_HLEN + UIP_LLH_LEN]; |
| frank26080115 | 0:bf7b9fba3924 | 432 | |
| frank26080115 | 0:bf7b9fba3924 | 433 | uip_len = sizeof(struct arp_hdr); |
| frank26080115 | 0:bf7b9fba3924 | 434 | return; |
| frank26080115 | 0:bf7b9fba3924 | 435 | } |
| frank26080115 | 0:bf7b9fba3924 | 436 | |
| frank26080115 | 0:bf7b9fba3924 | 437 | /* Build an ethernet header. */ |
| frank26080115 | 0:bf7b9fba3924 | 438 | memcpy(IPBUF->ethhdr.dest.addr, tabptr->ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 439 | } |
| frank26080115 | 0:bf7b9fba3924 | 440 | memcpy(IPBUF->ethhdr.src.addr, uip_ethaddr.addr, 6); |
| frank26080115 | 0:bf7b9fba3924 | 441 | |
| frank26080115 | 0:bf7b9fba3924 | 442 | IPBUF->ethhdr.type = HTONS(UIP_ETHTYPE_IP); |
| frank26080115 | 0:bf7b9fba3924 | 443 | |
| frank26080115 | 0:bf7b9fba3924 | 444 | uip_len += sizeof(struct uip_eth_hdr); |
| frank26080115 | 0:bf7b9fba3924 | 445 | } |
| frank26080115 | 0:bf7b9fba3924 | 446 | /*-----------------------------------------------------------------------------------*/ |
| frank26080115 | 0:bf7b9fba3924 | 447 | |
| frank26080115 | 0:bf7b9fba3924 | 448 | /** @} */ |
| frank26080115 | 0:bf7b9fba3924 | 449 | /** @} */ |