📄 net.c
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#endif
NetRxPkt = inpkt;
NetRxPktLen = len;
et = (Ethernet_t *)inpkt;
/* too small packet? */
if (len < ETHER_HDR_SIZE)
return;
#if (CONFIG_COMMANDS & CFG_CMD_CDP)
/* keep track if packet is CDP */
iscdp = memcmp(et->et_dest, NetCDPAddr, 6) == 0;
#endif
myvlanid = ntohs(NetOurVLAN);
if (myvlanid == (ushort)-1)
myvlanid = VLAN_NONE;
mynvlanid = ntohs(NetOurNativeVLAN);
if (mynvlanid == (ushort)-1)
mynvlanid = VLAN_NONE;
x = ntohs(et->et_protlen);
#ifdef ET_DEBUG
printf("packet received\n");
#endif
if (x < 1514) {
/*
* Got a 802 packet. Check the other protocol field.
*/
x = ntohs(et->et_prot);
ip = (IP_t *)(inpkt + E802_HDR_SIZE);
len -= E802_HDR_SIZE;
} else if (x != PROT_VLAN) { /* normal packet */
ip = (IP_t *)(inpkt + ETHER_HDR_SIZE);
len -= ETHER_HDR_SIZE;
} else { /* VLAN packet */
VLAN_Ethernet_t *vet = (VLAN_Ethernet_t *)et;
#ifdef ET_DEBUG
printf("VLAN packet received\n");
#endif
/* too small packet? */
if (len < VLAN_ETHER_HDR_SIZE)
return;
/* if no VLAN active */
if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
#if (CONFIG_COMMANDS & CFG_CMD_CDP)
&& iscdp == 0
#endif
)
return;
cti = ntohs(vet->vet_tag);
vlanid = cti & VLAN_IDMASK;
x = ntohs(vet->vet_type);
ip = (IP_t *)(inpkt + VLAN_ETHER_HDR_SIZE);
len -= VLAN_ETHER_HDR_SIZE;
}
#ifdef ET_DEBUG
printf("Receive from protocol 0x%x\n", x);
#endif
#if (CONFIG_COMMANDS & CFG_CMD_CDP)
if (iscdp) {
CDPHandler((uchar *)ip, len);
return;
}
#endif
if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
if (vlanid == VLAN_NONE)
vlanid = (mynvlanid & VLAN_IDMASK);
/* not matched? */
if (vlanid != (myvlanid & VLAN_IDMASK))
return;
}
switch (x) {
case PROT_ARP:
/*
* We have to deal with two types of ARP packets:
* - REQUEST packets will be answered by sending our
* IP address - if we know it.
* - REPLY packates are expected only after we asked
* for the TFTP server's or the gateway's ethernet
* address; so if we receive such a packet, we set
* the server ethernet address
*/
#ifdef ET_DEBUG
puts ("Got ARP\n");
#endif
arp = (ARP_t *)ip;
if (len < ARP_HDR_SIZE) {
printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
return;
}
if (ntohs(arp->ar_hrd) != ARP_ETHER) {
return;
}
if (ntohs(arp->ar_pro) != PROT_IP) {
return;
}
if (arp->ar_hln != 6) {
return;
}
if (arp->ar_pln != 4) {
return;
}
if (NetOurIP == 0) {
return;
}
if (NetReadIP(&arp->ar_data[16]) != NetOurIP) {
return;
}
switch (ntohs(arp->ar_op)) {
case ARPOP_REQUEST: /* reply with our IP address */
#ifdef ET_DEBUG
puts ("Got ARP REQUEST, return our IP\n");
#endif
pkt = (uchar *)et;
pkt += NetSetEther(pkt, et->et_src, PROT_ARP);
arp->ar_op = htons(ARPOP_REPLY);
memcpy (&arp->ar_data[10], &arp->ar_data[0], 6);
NetCopyIP(&arp->ar_data[16], &arp->ar_data[6]);
memcpy (&arp->ar_data[ 0], NetOurEther, 6);
NetCopyIP(&arp->ar_data[ 6], &NetOurIP);
(void) eth_send((uchar *)et, (pkt - (uchar *)et) + ARP_HDR_SIZE);
return;
case ARPOP_REPLY: /* arp reply */
/* are we waiting for a reply */
if (!NetArpWaitPacketIP || !NetArpWaitPacketMAC)
break;
#ifdef ET_DEBUG
printf("Got ARP REPLY, set server/gtwy eth addr (%02x:%02x:%02x:%02x:%02x:%02x)\n",
arp->ar_data[0], arp->ar_data[1],
arp->ar_data[2], arp->ar_data[3],
arp->ar_data[4], arp->ar_data[5]);
#endif
tmp = NetReadIP(&arp->ar_data[6]);
/* matched waiting packet's address */
if (tmp == NetArpWaitReplyIP) {
#ifdef ET_DEBUG
puts ("Got it\n");
#endif
/* save address for later use */
memcpy(NetArpWaitPacketMAC, &arp->ar_data[0], 6);
#ifdef CONFIG_NETCONSOLE
(*packetHandler)(0,0,0,0);
#endif
/* modify header, and transmit it */
memcpy(((Ethernet_t *)NetArpWaitTxPacket)->et_dest, NetArpWaitPacketMAC, 6);
(void) eth_send(NetArpWaitTxPacket, NetArpWaitTxPacketSize);
/* no arp request pending now */
NetArpWaitPacketIP = 0;
NetArpWaitTxPacketSize = 0;
NetArpWaitPacketMAC = NULL;
}
return;
default:
#ifdef ET_DEBUG
printf("Unexpected ARP opcode 0x%x\n", ntohs(arp->ar_op));
#endif
return;
}
case PROT_RARP:
#ifdef ET_DEBUG
puts ("Got RARP\n");
#endif
arp = (ARP_t *)ip;
if (len < ARP_HDR_SIZE) {
printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
return;
}
if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
(ntohs(arp->ar_hrd) != ARP_ETHER) ||
(ntohs(arp->ar_pro) != PROT_IP) ||
(arp->ar_hln != 6) || (arp->ar_pln != 4)) {
puts ("invalid RARP header\n");
} else {
NetCopyIP(&NetOurIP, &arp->ar_data[16]);
if (NetServerIP == 0)
NetCopyIP(&NetServerIP, &arp->ar_data[ 6]);
memcpy (NetServerEther, &arp->ar_data[ 0], 6);
(*packetHandler)(0,0,0,0);
}
break;
case PROT_IP:
#ifdef ET_DEBUG
puts ("Got IP\n");
#endif
if (len < IP_HDR_SIZE) {
debug ("len bad %d < %d\n", len, IP_HDR_SIZE);
return;
}
if (len < ntohs(ip->ip_len)) {
printf("len bad %d < %d\n", len, ntohs(ip->ip_len));
return;
}
len = ntohs(ip->ip_len);
#ifdef ET_DEBUG
printf("len=%d, v=%02x\n", len, ip->ip_hl_v & 0xff);
#endif
if ((ip->ip_hl_v & 0xf0) != 0x40) {
return;
}
if (ip->ip_off & htons(0x1fff)) { /* Can't deal w/ fragments */
return;
}
if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2)) {
puts ("checksum bad\n");
return;
}
tmp = NetReadIP(&ip->ip_dst);
if (NetOurIP && tmp != NetOurIP && tmp != 0xFFFFFFFF) {
return;
}
/*
* watch for ICMP host redirects
*
* There is no real handler code (yet). We just watch
* for ICMP host redirect messages. In case anybody
* sees these messages: please contact me
* (wd@denx.de), or - even better - send me the
* necessary fixes :-)
*
* Note: in all cases where I have seen this so far
* it was a problem with the router configuration,
* for instance when a router was configured in the
* BOOTP reply, but the TFTP server was on the same
* subnet. So this is probably a warning that your
* configuration might be wrong. But I'm not really
* sure if there aren't any other situations.
*/
if (ip->ip_p == IPPROTO_ICMP) {
ICMP_t *icmph = (ICMP_t *)&(ip->udp_src);
switch (icmph->type) {
case ICMP_REDIRECT:
if (icmph->code != ICMP_REDIR_HOST)
return;
puts (" ICMP Host Redirect to ");
print_IPaddr(icmph->un.gateway);
putc(' ');
break;
#if (CONFIG_COMMANDS & CFG_CMD_PING)
case ICMP_ECHO_REPLY:
/*
* IP header OK. Pass the packet to the current handler.
*/
/* XXX point to ip packet */
(*packetHandler)((uchar *)ip, 0, 0, 0);
break;
#endif
default:
return;
}
} else if (ip->ip_p != IPPROTO_UDP) { /* Only UDP packets */
return;
}
#ifdef CONFIG_NETCONSOLE
nc_input_packet((uchar *)ip +IP_HDR_SIZE,
ntohs(ip->udp_dst),
ntohs(ip->udp_src),
ntohs(ip->udp_len) - 8);
#endif
/*
* IP header OK. Pass the packet to the current handler.
*/
(*packetHandler)((uchar *)ip +IP_HDR_SIZE,
ntohs(ip->udp_dst),
ntohs(ip->udp_src),
ntohs(ip->udp_len) - 8);
break;
}
}
/**********************************************************************/
static int net_check_prereq (proto_t protocol)
{
switch (protocol) {
/* Fall through */
#if (CONFIG_COMMANDS & CFG_CMD_PING)
case PING:
if (NetPingIP == 0) {
puts ("*** ERROR: ping address not given\n");
return (1);
}
goto common;
#endif
#if (CONFIG_COMMANDS & CFG_CMD_NFS)
case NFS:
#endif
case NETCONS:
case TFTP:
if (NetServerIP == 0) {
puts ("*** ERROR: `serverip' not set\n");
return (1);
}
#if (CONFIG_COMMANDS & CFG_CMD_PING)
common:
#endif
if (NetOurIP == 0) {
puts ("*** ERROR: `ipaddr' not set\n");
return (1);
}
/* Fall through */
case DHCP:
case RARP:
case BOOTP:
case CDP:
if (memcmp (NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
#ifdef CONFIG_NET_MULTI
extern int eth_get_dev_index (void);
int num = eth_get_dev_index ();
switch (num) {
case -1:
puts ("*** ERROR: No ethernet found.\n");
return (1);
case 0:
puts ("*** ERROR: `ethaddr' not set\n");
break;
default:
printf ("*** ERROR: `eth%daddr' not set\n",
num);
break;
}
NetStartAgain ();
return (2);
#else
puts ("*** ERROR: `ethaddr' not set\n");
return (1);
#endif
}
/* Fall through */
default:
return (0);
}
return (0); /* OK */
}
/**********************************************************************/
int
NetCksumOk(uchar * ptr, int len)
{
return !((NetCksum(ptr, len) + 1) & 0xfffe);
}
unsigned
NetCksum(uchar * ptr, int len)
{
ulong xsum;
xsum = 0;
while (len-- > 0)
xsum += *((ushort *)ptr)++;
xsum = (xsum & 0xffff) + (xsum >> 16);
xsum = (xsum & 0xffff) + (xsum >> 16);
return (xsum & 0xffff);
}
int
NetEthHdrSize(void)
{
ushort myvlanid;
myvlanid = ntohs(NetOurVLAN);
if (myvlanid == (ushort)-1)
myvlanid = VLAN_NONE;
return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE : VLAN_ETHER_HDR_SIZE;
}
int
NetSetEther(volatile uchar * xet, uchar * addr, uint prot)
{
Ethernet_t *et = (Ethernet_t *)xet;
ushort myvlanid;
myvlanid = ntohs(NetOurVLAN);
if (myvlanid == (ushort)-1)
myvlanid = VLAN_NONE;
memcpy (et->et_dest, addr, 6);
memcpy (et->et_src, NetOurEther, 6);
if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
et->et_protlen = htons(prot);
return ETHER_HDR_SIZE;
} else {
VLAN_Ethernet_t *vet = (VLAN_Ethernet_t *)xet;
vet->vet_vlan_type = htons(PROT_VLAN);
vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
vet->vet_type = htons(prot);
return VLAN_ETHER_HDR_SIZE;
}
}
void
NetSetIP(volatile uchar * xip, IPaddr_t dest, int dport, int sport, int len)
{
volatile IP_t *ip = (IP_t *)xip;
/*
* If the data is an odd number of bytes, zero the
* byte after the last byte so that the checksum
* will work.
*/
if (len & 1)
xip[IP_HDR_SIZE + len] = 0;
/*
* Construct an IP and UDP header.
* (need to set no fragment bit - XXX)
*/
ip->ip_hl_v = 0x45; /* IP_HDR_SIZE / 4 (not including UDP) */
ip->ip_tos = 0;
ip->ip_len = htons(IP_HDR_SIZE + len);
ip->ip_id = htons(NetIPID++);
ip->ip_off = htons(0x4000); /* No fragmentation */
ip->ip_ttl = 255;
ip->ip_p = 17; /* UDP */
ip->ip_sum = 0;
NetCopyIP((void*)&ip->ip_src, &NetOurIP); /* already in network byte order */
NetCopyIP((void*)&ip->ip_dst, &dest); /* - "" - */
ip->udp_src = htons(sport);
ip->udp_dst = htons(dport);
ip->udp_len = htons(8 + len);
ip->udp_xsum = 0;
ip->ip_sum = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
}
void copy_filename (uchar *dst, uchar *src, int size)
{
if (*src && (*src == '"')) {
++src;
--size;
}
while ((--size > 0) && *src && (*src != '"')) {
*dst++ = *src++;
}
*dst = '\0';
}
#endif /* CFG_CMD_NET */
void ip_to_string (IPaddr_t x, char *s)
{
x = ntohl (x);
sprintf (s, "%d.%d.%d.%d",
(int) ((x >> 24) & 0xff),
(int) ((x >> 16) & 0xff),
(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
);
}
IPaddr_t string_to_ip(char *s)
{
IPaddr_t addr;
char *e;
int i;
if (s == NULL)
return(0);
for (addr=0, i=0; i<4; ++i) {
ulong val = s ? simple_strtoul(s, &e, 10) : 0;
addr <<= 8;
addr |= (val & 0xFF);
if (s) {
s = (*e) ? e+1 : e;
}
}
return (htonl(addr));
}
void VLAN_to_string(ushort x, char *s)
{
x = ntohs(x);
if (x == (ushort)-1)
x = VLAN_NONE;
if (x == VLAN_NONE)
strcpy(s, "none");
else
sprintf(s, "%d", x & VLAN_IDMASK);
}
ushort string_to_VLAN(char *s)
{
ushort id;
if (s == NULL)
return htons(VLAN_NONE);
if (*s < '0' || *s > '9')
id = VLAN_NONE;
else
id = (ushort)simple_strtoul(s, NULL, 10);
return htons(id);
}
void print_IPaddr (IPaddr_t x)
{
char tmp[16];
ip_to_string (x, tmp);
puts (tmp);
}
IPaddr_t getenv_IPaddr (char *var)
{
return (string_to_ip(getenv(var)));
}
ushort getenv_VLAN(char *var)
{
return (string_to_VLAN(getenv(var)));
}
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