diff options
Diffstat (limited to 'net/arp.c')
-rw-r--r-- | net/arp.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/net/arp.c b/net/arp.c new file mode 100644 index 0000000..c09dc1a --- /dev/null +++ b/net/arp.c @@ -0,0 +1,120 @@ +/* + * (C) Copyright 2000 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> +#include <command.h> +#include <net.h> +#include "bootp.h" +#include "tftp.h" +#include "arp.h" + +#if (CONFIG_COMMANDS & CFG_CMD_NET) + +#define TIMEOUT 5 /* Seconds before trying ARP again */ +#ifndef CONFIG_NET_RETRY_COUNT +# define TIMEOUT_COUNT 5 /* # of timeouts before giving up */ +#else +# define TIMEOUT_COUNT (CONFIG_NET_RETRY_COUNT) +#endif + +static void ArpHandler(uchar *pkt, unsigned dest, unsigned src, unsigned len); +static void ArpTimeout(void); + +int ArpTry = 0; + +/* + * Handle a ARP received packet. + */ +static void +ArpHandler(uchar *pkt, unsigned dest, unsigned src, unsigned len) +{ + /* Check if the frame is really an ARP reply */ + if (memcmp (NetServerEther, NetBcastAddr, 6) != 0) { +#ifdef DEBUG + printf("Got good ARP - start TFTP\n"); +#endif + TftpStart (); + } +} + + +/* + * Timeout on ARP request. + */ +static void +ArpTimeout(void) +{ + if (ArpTry >= TIMEOUT_COUNT) { + puts ("\nRetry count exceeded; starting again\n"); + NetStartAgain (); + } else { + NetSetTimeout (TIMEOUT * CFG_HZ, ArpTimeout); + ArpRequest (); + } +} + + +void +ArpRequest (void) +{ + int i; + volatile uchar *pkt; + ARP_t * arp; + + printf("ARP broadcast %d\n", ++ArpTry); + pkt = NetTxPacket; + + NetSetEther(pkt, NetBcastAddr, PROT_ARP); + pkt += ETHER_HDR_SIZE; + + arp = (ARP_t *)pkt; + + arp->ar_hrd = htons(ARP_ETHER); + arp->ar_pro = htons(PROT_IP); + arp->ar_hln = 6; + arp->ar_pln = 4; + arp->ar_op = htons(ARPOP_REQUEST); + + memcpy (&arp->ar_data[0], NetOurEther, 6); /* source ET addr */ + NetWriteIP((uchar*)&arp->ar_data[6], NetOurIP); /* source IP addr */ + for (i=10; i<16; ++i) { + arp->ar_data[i] = 0; /* dest ET addr = 0 */ + } + + if((NetServerIP & NetOurSubnetMask) != (NetOurIP & NetOurSubnetMask)) { + if (NetOurGatewayIP == 0) { + puts ("## Warning: gatewayip needed but not set\n"); + } + NetWriteIP((uchar*)&arp->ar_data[16], NetOurGatewayIP); + } else { + NetWriteIP((uchar*)&arp->ar_data[16], NetServerIP); + } + + + NetSendPacket(NetTxPacket, ETHER_HDR_SIZE + ARP_HDR_SIZE); + + NetSetTimeout(TIMEOUT * CFG_HZ, ArpTimeout); + NetSetHandler(ArpHandler); +} + +#endif /* CFG_CMD_NET */ |