1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
|
/*
* Copied from Linux Monitor (LiMon) - Networking.
*
* Copyright 1994 - 2000 Neil Russell.
* (See License)
* Copyright 2000 Roland Borde
* Copyright 2000 Paolo Scaffardi
* Copyright 2000-2002 Wolfgang Denk, wd@denx.de
*/
#include "ping.h"
#include "arp.h"
static ushort PingSeqNo;
/* The ip address to ping */
IPaddr_t NetPingIP;
static void set_icmp_header(uchar *pkt, IPaddr_t dest)
{
/*
* Construct an IP and ICMP header.
*/
struct ip_hdr *ip = (struct ip_hdr *)pkt;
struct icmp_hdr *icmp = (struct icmp_hdr *)(pkt + IP_HDR_SIZE);
net_set_ip_header(pkt, dest, NetOurIP);
ip->ip_len = htons(IP_ICMP_HDR_SIZE);
ip->ip_p = IPPROTO_ICMP;
ip->ip_sum = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
icmp->type = ICMP_ECHO_REQUEST;
icmp->code = 0;
icmp->checksum = 0;
icmp->un.echo.id = 0;
icmp->un.echo.sequence = htons(PingSeqNo++);
icmp->checksum = ~NetCksum((uchar *)icmp, ICMP_HDR_SIZE >> 1);
}
static int ping_send(void)
{
static uchar mac[6];
uchar *pkt;
int eth_hdr_size;
/* XXX always send arp request */
memcpy(mac, NetEtherNullAddr, 6);
debug("sending ARP for %pI4\n", &NetPingIP);
NetArpWaitPacketIP = NetPingIP;
NetArpWaitPacketMAC = mac;
pkt = NetArpWaitTxPacket;
eth_hdr_size = NetSetEther(pkt, mac, PROT_IP);
pkt += eth_hdr_size;
set_icmp_header(pkt, NetPingIP);
/* size of the waiting packet */
NetArpWaitTxPacketSize = eth_hdr_size + IP_ICMP_HDR_SIZE;
/* and do the ARP request */
NetArpWaitTry = 1;
NetArpWaitTimerStart = get_timer(0);
ArpRequest();
return 1; /* waiting */
}
static void ping_timeout(void)
{
eth_halt();
NetState = NETLOOP_FAIL; /* we did not get the reply */
}
void ping_start(void)
{
printf("Using %s device\n", eth_get_name());
NetSetTimeout(10000UL, ping_timeout);
ping_send();
}
void ping_receive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
{
struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
IPaddr_t src_ip;
switch (icmph->type) {
case ICMP_ECHO_REPLY:
src_ip = NetReadIP((void *)&ip->ip_src);
if (src_ip == NetPingIP)
NetState = NETLOOP_SUCCESS;
return;
case ICMP_ECHO_REQUEST:
debug("Got ICMP ECHO REQUEST, return "
"%d bytes\n", ETHER_HDR_SIZE + len);
memcpy(&et->et_dest[0], &et->et_src[0], 6);
memcpy(&et->et_src[0], NetOurEther, 6);
ip->ip_sum = 0;
ip->ip_off = 0;
NetCopyIP((void *)&ip->ip_dst, &ip->ip_src);
NetCopyIP((void *)&ip->ip_src, &NetOurIP);
ip->ip_sum = ~NetCksum((uchar *)ip,
IP_HDR_SIZE >> 1);
icmph->type = ICMP_ECHO_REPLY;
icmph->checksum = 0;
icmph->checksum = ~NetCksum((uchar *)icmph,
(len - IP_HDR_SIZE) >> 1);
(void) eth_send((uchar *)et,
ETHER_HDR_SIZE + len);
return;
/* default:
return;*/
}
}
|
