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
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
|
/*
* 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 int ping_send(void)
{
static uchar mac[6];
struct ip_udp_hdr *ip;
ushort *s;
uchar *pkt;
/* XXX always send arp request */
memcpy(mac, NetEtherNullAddr, 6);
debug("sending ARP for %pI4\n", &NetPingIP);
NetArpWaitPacketIP = NetPingIP;
NetArpWaitPacketMAC = mac;
pkt = NetArpWaitTxPacket;
pkt += NetSetEther(pkt, mac, PROT_IP);
ip = (struct ip_udp_hdr *)pkt;
/*
* Construct an IP and ICMP header.
* (need to set no fragment bit - XXX)
*/
/* IP_HDR_SIZE / 4 (not including UDP) */
ip->ip_hl_v = 0x45;
ip->ip_tos = 0;
ip->ip_len = htons(IP_HDR_SIZE + 8);
ip->ip_id = htons(NetIPID++);
ip->ip_off = htons(IP_FLAGS_DFRAG); /* Don't fragment */
ip->ip_ttl = 255;
ip->ip_p = 0x01; /* ICMP */
ip->ip_sum = 0;
/* already in network byte order */
NetCopyIP((void *)&ip->ip_src, &NetOurIP);
/* - "" - */
NetCopyIP((void *)&ip->ip_dst, &NetPingIP);
ip->ip_sum = ~NetCksum((uchar *)ip, IP_HDR_SIZE / 2);
s = &ip->udp_src; /* XXX ICMP starts here */
s[0] = htons(0x0800); /* echo-request, code */
s[1] = 0; /* checksum */
s[2] = 0; /* identifier */
s[3] = htons(PingSeqNo++); /* sequence number */
s[1] = ~NetCksum((uchar *)s, 8/2);
/* size of the waiting packet */
NetArpWaitTxPacketSize =
(pkt - NetArpWaitTxPacket) + IP_HDR_SIZE + 8;
/* 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 */
}
static void ping_handler(uchar *pkt, unsigned dest, IPaddr_t sip,
unsigned src, unsigned len)
{
if (sip != NetPingIP)
return;
NetState = NETLOOP_SUCCESS;
}
void ping_start(void)
{
printf("Using %s device\n", eth_get_name());
NetSetTimeout(10000UL, ping_timeout);
NetSetHandler(ping_handler);
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:
/*
* IP header OK. Pass the packet to the
* current handler.
*/
/* XXX point to ip packet */
src_ip = NetReadIP((void *)&ip->ip_src);
NetGetHandler()((uchar *)ip, 0, src_ip, 0, 0);
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;*/
}
}
|
