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/*
* Linux ARCnet driver - RFC1201 (standard) packet encapsulation
*
* Written 1994-1999 by Avery Pennarun.
* Derived from skeleton.c by Donald Becker.
*
* Special thanks to Contemporary Controls, Inc. (www.ccontrols.com)
* for sponsoring the further development of this driver.
*
* **********************
*
* The original copyright of skeleton.c was as follows:
*
* skeleton.c Written 1993 by Donald Becker.
* Copyright 1993 United States Government as represented by the
* Director, National Security Agency. This software may only be used
* and distributed according to the terms of the GNU General Public License as
* modified by SRC, incorporated herein by reference.
*
* **********************
*
* For more details, see drivers/net/arcnet.c
*
* **********************
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/if_arp.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/arcdevice.h>
MODULE_LICENSE("GPL");
#define VERSION "arcnet: RFC1201 \"standard\" (`a') encapsulation support loaded.\n"
static __be16 type_trans(struct sk_buff *skb, struct net_device *dev);
static void rx(struct net_device *dev, int bufnum,
struct archdr *pkthdr, int length);
static int build_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type, uint8_t daddr);
static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
int bufnum);
static int continue_tx(struct net_device *dev, int bufnum);
static struct ArcProto rfc1201_proto =
{
.suffix = 'a',
.mtu = 1500, /* could be more, but some receivers can't handle it... */
.is_ip = 1, /* This is for sending IP and ARP packages */
.rx = rx,
.build_header = build_header,
.prepare_tx = prepare_tx,
.continue_tx = continue_tx,
.ack_tx = NULL
};
static int __init arcnet_rfc1201_init(void)
{
printk(VERSION);
arc_proto_map[ARC_P_IP]
= arc_proto_map[ARC_P_IPV6]
= arc_proto_map[ARC_P_ARP]
= arc_proto_map[ARC_P_RARP]
= arc_proto_map[ARC_P_IPX]
= arc_proto_map[ARC_P_NOVELL_EC]
= &rfc1201_proto;
/* if someone else already owns the broadcast, we won't take it */
if (arc_bcast_proto == arc_proto_default)
arc_bcast_proto = &rfc1201_proto;
return 0;
}
static void __exit arcnet_rfc1201_exit(void)
{
arcnet_unregister_proto(&rfc1201_proto);
}
module_init(arcnet_rfc1201_init);
module_exit(arcnet_rfc1201_exit);
/*
* Determine a packet's protocol ID.
*
* With ARCnet we have to convert everything to Ethernet-style stuff.
*/
static __be16 type_trans(struct sk_buff *skb, struct net_device *dev)
{
struct archdr *pkt = (struct archdr *) skb->data;
struct arc_rfc1201 *soft = &pkt->soft.rfc1201;
struct arcnet_local *lp = dev->priv;
int hdr_size = ARC_HDR_SIZE + RFC1201_HDR_SIZE;
/* Pull off the arcnet header. */
skb_reset_mac_header(skb);
skb_pull(skb, hdr_size);
if (pkt->hard.dest == 0)
skb->pkt_type = PACKET_BROADCAST;
else if (dev->flags & IFF_PROMISC) {
/* if we're not sending to ourselves :) */
if (pkt->hard.dest != dev->dev_addr[0])
skb->pkt_type = PACKET_OTHERHOST;
}
/* now return the protocol number */
switch (soft->proto) {
case ARC_P_IP:
return htons(ETH_P_IP);
case ARC_P_IPV6:
return htons(ETH_P_IPV6);
case ARC_P_ARP:
return htons(ETH_P_ARP);
case ARC_P_RARP:
return htons(ETH_P_RARP);
case ARC_P_IPX:
case ARC_P_NOVELL_EC:
return htons(ETH_P_802_3);
default:
lp->stats.rx_errors++;
lp->stats.rx_crc_errors++;
return 0;
}
return htons(ETH_P_IP);
}
/* packet receiver */
static void rx(struct net_device *dev, int bufnum,
struct archdr *pkthdr, int length)
{
struct arcnet_local *lp = dev->priv;
struct sk_buff *skb;
struct archdr *pkt = pkthdr;
struct arc_rfc1201 *soft = &pkthdr->soft.rfc1201;
int saddr = pkt->hard.source, ofs;
struct Incoming *in = &lp->rfc1201.incoming[saddr];
BUGMSG(D_DURING, "it's an RFC1201 packet (length=%d)\n", length);
if (length >= MinTU)
ofs = 512 - length;
else
ofs = 256 - length;
if (soft->split_flag == 0xFF) { /* Exception Packet */
if (length >= 4 + RFC1201_HDR_SIZE)
BUGMSG(D_DURING, "compensating for exception packet\n");
else {
BUGMSG(D_EXTRA, "short RFC1201 exception packet from %02Xh",
saddr);
return;
}
/* skip over 4-byte junkola */
length -= 4;
ofs += 4;
lp->hw.copy_from_card(dev, bufnum, 512 - length,
soft, sizeof(pkt->soft));
}
if (!soft->split_flag) { /* not split */
BUGMSG(D_RX, "incoming is not split (splitflag=%d)\n",
soft->split_flag);
if (in->skb) { /* already assembling one! */
BUGMSG(D_EXTRA, "aborting assembly (seq=%d) for unsplit packet (splitflag=%d, seq=%d)\n",
in->sequence, soft->split_flag, soft->sequence);
lp->rfc1201.aborted_seq = soft->sequence;
dev_kfree_skb_irq(in->skb);
lp->stats.rx_errors++;
lp->stats.rx_missed_errors++;
in->skb = NULL;
}
in->sequence = soft->sequence;
skb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
if (skb == NULL) {
BUGMSG(D_NORMAL, "Memory squeeze, dropping packet.\n");
lp->stats.rx_dropped++;
return;
}
skb_put(skb, length + ARC_HDR_SIZE);
skb->dev = dev;
pkt = (struct archdr *) skb->data;
soft = &pkt->soft.rfc1201;
/* up to sizeof(pkt->soft) has already been copied from the card */
memcpy(pkt, pkthdr, sizeof(struct archdr));
if (length > sizeof(pkt->soft))
lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
pkt->soft.raw + sizeof(pkt->soft),
length - sizeof(pkt->soft));
/*
* ARP packets have problems when sent from some DOS systems: the
* source address is always 0! So we take the hardware source addr
* (which is impossible to fumble) and insert it ourselves.
*/
if (soft->proto == ARC_P_ARP) {
struct arphdr *arp = (struct arphdr *) soft->payload;
/* make sure addresses are the right length */
if (arp->ar_hln == 1 && arp->ar_pln == 4) {
uint8_t *cptr = (uint8_t *) arp + sizeof(struct arphdr);
if (!*cptr) { /* is saddr = 00? */
BUGMSG(D_EXTRA,
"ARP source address was 00h, set to %02Xh.\n",
saddr);
lp->stats.rx_crc_errors++;
*cptr =
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