linux/net/802/tr.c

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/*
* NET3: Token ring device handling subroutines
*
* 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.
*
* Fixes: 3 Feb 97 Paul Norton <pnorton@cts.com> Minor routing fixes.
* Added rif table to /proc/net/tr_rif and rif timeout to
* /proc/sys/net/token-ring/rif_timeout.
* 22 Jun 98 Paul Norton <p.norton@computer.org> Rearranged
* tr_header and tr_type_trans to handle passing IPX SNAP and
* 802.2 through the correct layers. Eliminated tr_reformat.
*
*/
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/trdevice.h>
#include <linux/skbuff.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/net.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <net/arp.h>
#include <net/net_namespace.h>
static void tr_add_rif_info(struct trh_hdr *trh, struct net_device *dev);
static void rif_check_expire(unsigned long dummy);
#define TR_SR_DEBUG 0
/*
* Each RIF entry we learn is kept this way
*/
struct rif_cache {
unsigned char addr[TR_ALEN];
int iface;
__be16 rcf;
__be16 rseg[8];
struct rif_cache *next;
unsigned long last_used;
unsigned char local_ring;
};
#define RIF_TABLE_SIZE 32
/*
* We hash the RIF cache 32 ways. We do after all have to look it
* up a lot.
*/
static struct rif_cache *rif_table[RIF_TABLE_SIZE];
static DEFINE_SPINLOCK(rif_lock);
/*
* Garbage disposal timer.
*/
static struct timer_list rif_timer;
int sysctl_tr_rif_timeout = 60*10*HZ;
static inline unsigned long rif_hash(const unsigned char *addr)
{
unsigned long x;
x = addr[0];
x = (x << 2) ^ addr[1];
x = (x << 2) ^ addr[2];
x = (x << 2) ^ addr[3];
x = (x << 2) ^ addr[4];
x = (x << 2) ^ addr[5];
x ^= x >> 8;
return x & (RIF_TABLE_SIZE - 1);
}
/*
* Put the headers on a token ring packet. Token ring source routing
* makes this a little more exciting than on ethernet.
*/
static int tr_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type,
const void *daddr, const void *saddr, unsigned len)
{
struct trh_hdr *trh;
int hdr_len;
/*
* Add the 802.2 SNAP header if IP as the IPv4/IPv6 code calls
* dev->hard_header directly.
*/
if (type == ETH_P_IP || type == ETH_P_IPV6 || type == ETH_P_ARP)
{
struct trllc *trllc;
hdr_len = sizeof(struct trh_hdr) + sizeof(struct trllc);
trh = (struct trh_hdr *)skb_push(skb, hdr_len);
trllc = (struct trllc *)(trh+1);
trllc->dsap = trllc->ssap = EXTENDED_SAP;
trllc->llc = UI_CMD;
trllc->protid[0] = trllc->protid[1] = trllc->protid[2] = 0x00;
trllc->ethertype = htons(type);
}
else
{
hdr_len = sizeof(struct trh_hdr);
trh = (struct trh_hdr *)skb_push(skb, hdr_len);
}
trh->ac=AC;
trh->fc=LLC_FRAME;
if(saddr)
memcpy(trh->saddr,saddr,dev->addr_len);
else
memcpy(trh->saddr,dev->dev_addr,dev->addr_len);
/*
* Build the destination and then source route the frame
*/
if(daddr)
{
memcpy(trh->daddr,daddr,dev->addr_len);
tr_source_route(skb, trh, dev);
return(hdr_len);
}
return -hdr_len;
}
/*
* A neighbour discovery of some species (eg arp) has completed. We
* can now send the packet.
*/
static int tr_rebuild_header(struct sk_buff *skb)
{
struct trh_hdr *trh=(struct trh_hdr *)skb->data;
struct trllc *trllc=(struct trllc *)(skb->data+sizeof(struct trh_hdr));
struct net_device *dev = skb->dev;
/*
* FIXME: We don't yet support IPv6 over token rings
*/
if(trllc->ethertype != htons(ETH_P_IP)) {
printk("tr_rebuild_header: Don't know how to resolve type %04X addresses ?\n", ntohs(trllc->ethertype));
return 0;
}
#ifdef CONFIG_INET
if(arp_find(trh->daddr, skb)) {
return 1;
}
else
#endif
{
tr_source_route(skb,trh,dev);
return 0;
}
}
/*
* Some of this is a bit hackish. We intercept RIF information
* used for source routing. We also grab IP directly and don't feed
* it via SNAP.
*/
__be16 tr_type_trans(struct sk_buff *skb, struct net_device *dev)
{
struct trh_hdr *trh;
struct trllc *trllc;
unsigned riflen=0;
skb->dev = dev;
skb_reset_mac_header(skb);
trh = tr_hdr(skb);
if(trh->saddr[0] & TR_RII)
riflen = (ntohs(trh->rcf) & TR_RCF_LEN_MASK) >> 8;
trllc = (struct trllc *)(skb->data+sizeof(struct trh_hdr)-TR_MAXRIFLEN+riflen);
skb_pull(skb,sizeof(struct trh_hdr)-TR_MAXRIFLEN+riflen);
if(*trh->daddr & 0x80)
{
if(!memcmp(trh->daddr,dev->broadcast,TR_ALEN))
skb->pkt_type=PACKET_BROADCAST;
else
skb->pkt_type=PACKET_MULTICAST;
}
else if ( (trh->daddr[0] & 0x01) && (trh->daddr[1] & 0x00) && (trh->daddr[2] & 0x5E))
{
skb->pkt_type=PACKET_MULTICAST;
}
else if(dev->flags & IFF_PROMISC)
{
if(memcmp(trh->daddr, dev->dev_addr, TR_ALEN))
skb->pkt_type=PACKET_OTHERHOST;
}
if ((skb->pkt_type != PACKET_BROADCAST) &&
(skb->pkt_type != PACKET_MULTICAST))
tr_add_rif_info(trh,dev) ;
/*
* Strip the SNAP header from ARP packets since we don't
* pass them through to the 802.2/SNAP layers.
*/
if (trllc->dsap == EXTENDED_SAP &&
(trllc->ethertype == htons(ETH_P_IP) ||
trllc->ethertype == htons(ETH_P_IPV6) ||
trllc->ethertype == htons(ETH_P_ARP)))
{
skb_pull(skb, sizeof(struct trllc));
return trllc->ethertype;
}
return htons(ETH_P_TR_802_2);
}
/*
* We try to do source routing...
*/
void tr_source_route(struct sk_buff *skb,struct trh_hdr *trh,
struct net_device *dev)
{
int slack;
unsigned int hash;
struct rif_cache *entry;
unsigned char *olddata;
unsigned long flags;
static const unsigned char mcast_func_addr[]
= {0xC0,0x00,0x00,0x04,0x00,0x00};
spin_lock_irqsave(&rif_lock, flags);
/*
* Broadcasts are single route as stated in RFC 1042
*/
if( (!memcmp(&(trh->daddr[0]),&(dev->broadcast[0]),TR_ALEN)) ||
(!memcmp(&(trh->daddr[0]),&(mcast_func_addr[0]), TR_ALEN)) )
{
trh->rcf=htons((((sizeof(trh->rcf)) << 8) & TR_RCF_LEN_MASK)
| TR_RCF_FRAME2K | TR_RCF_LIMITED_BROADCAST);
trh->saddr[0]|=TR_RII;
}
else
{
hash = rif_hash(trh->daddr);
/*
* Walk the hash table and look for an entry
*/
for(entry=rif_table[hash];entry && memcmp(&(entry->addr[0]),&(trh->daddr[0]),TR_ALEN);entry=entry->next);
/*
* If we found an entry we can route the frame.
*/
if(entry)
{
#if TR_SR_DEBUG
{
DECLARE_MAC_BUF(mac);
printk("source routing for %s\n",print_mac(mac, trh->daddr));
}
#endif
if(!entry->local_ring && (ntohs(entry->rcf) & TR_RCF_LEN_MASK) >> 8)
{
trh->rcf=entry->rcf;
memcpy(&trh->rseg[0],&entry->rseg[0],8*sizeof(unsigned short));
trh->rcf^=htons(TR_RCF_DIR_BIT);
trh->rcf&=htons(0x1fff); /* Issam Chehab <ichehab@madge1.demon.co.uk> */
trh->saddr[0]|=TR_RII;
#if TR_SR_DEBUG
printk("entry found with rcf %04x\n", entry->rcf);
}
else
{
printk("entry found but without rcf length, local=%02x\n", entry->local_ring);
#endif
}
entry->last_used=jiffies;
}
else
{
/*
* Without the information we simply have to shout
* on the wire. The replies should rapidly clean this
* situation up.
*/
trh->rcf=htons((((sizeof(trh->rcf)) << 8) & TR_RCF_LEN_MASK)
| TR_RCF_FRAME2K | TR_RCF_LIMITED_BROADCAST);
trh->saddr[0]|=TR_RII;
#if TR_SR_DEBUG
printk("no entry in rif table found - broadcasting frame\n");
#endif
}
}
/* Compress the RIF here so we don't have to do it in the driver(s) */
if (!(trh->saddr[0] & 0x80))
slack = 18;
else
slack = 18 - ((ntohs(trh->rcf) & TR_RCF_LEN_MASK)>>8);
olddata = skb->data;
spin_unlock_irqrestore(&rif_lock, flags);
skb_pull(skb, slack);
memmove(skb->data, olddata, sizeof(struct trh_hdr) - slack);
}
/*
* We have learned some new RIF information for our source
* routing.
*/
static void tr_add_rif_info(struct trh_hdr *trh, struct net_device *dev)
{
unsigned int hash, rii_p = 0;
unsigned long flags;
struct rif_cache *entry;
unsigned char saddr0;
spin_lock_irqsave(&rif_lock, flags);
saddr0 = trh->saddr[0];
/*
* Firstly see if the entry exists
*/
if(trh->saddr[0] & TR_RII)
{
trh->saddr[0]&=0x7f;
if (((ntohs(trh->rcf) & TR_RCF_LEN_MASK) >> 8) > 2)
{
rii_p = 1;
}
}
hash = rif_hash(trh->saddr);
for(entry=rif_table[hash];entry && memcmp(&(entry->addr[0]),&(trh->saddr[0]),TR_ALEN);entry=entry->next);
if(entry==NULL)
{
#if TR_SR_DEBUG
DECLARE_MAC_BUF(mac);
printk("adding rif_entry: addr:%s rcf:%04X\n",
print_mac(mac, trh->saddr), ntohs(trh->rcf));
#endif
/*
* Allocate our new entry. A failure to allocate loses
* use the information. This is harmless.
*
* FIXME: We ought to keep some kind of cache size
* limiting and adjust the timers to suit.
*/
entry=kmalloc(sizeof(struct rif_cache),GFP_ATOMIC);
if(!entry)
{
printk(KERN_DEBUG "tr.c: Couldn't malloc rif cache entry !\n");
spin_unlock_irqrestore(&rif_lock, flags);
return;
}
memcpy(&(entry->addr[0]),&(trh->saddr[0]),TR_ALEN);
entry->iface = dev->ifindex;
entry->next=rif_table[hash];
entry->last_used=jiffies;
rif_table[hash]=entry;
if (rii_p)
{
entry->rcf = trh->rcf & htons((unsigned short)~TR_RCF_BROADCAST_MASK);
memcpy(&(entry->rseg[0]),&(trh->rseg[0]),8*sizeof(unsigned short));
entry->local_ring = 0;
}
else
{
entry->local_ring = 1;
}
}
else /* Y. Tahara added */
{
/*
* Update existing entries
*/
if (!entry->local_ring)
if (entry->rcf != (trh->rcf & htons((unsigned short)~TR_RCF_BROADCAST_MASK)) &&
!(trh->rcf & htons(TR_RCF_BROADCAST_MASK)))
{
#if TR_SR_DEBUG
{
DECLARE_MAC_BUF(mac);
printk("updating rif_entry: addr:%s rcf:%04X\n",
print_mac(mac, trh->saddr), ntohs(trh->rcf));
}
#endif
entry->rcf = trh->rcf & htons((unsigned short)~TR_RCF_BROADCAST_MASK);
memcpy(&(entry->rseg[0]),&(trh->rseg[0]),8*sizeof(unsigned short));
}
entry->last_used=jiffies;
}
trh->saddr[0]=saddr0; /* put the routing indicator back for tcpdump */
spin_unlock_irqrestore(&rif_lock, flags);
}
/*
* Scan the cache with a timer and see what we need to throw out.
*/
static void rif_check_expire(unsigned long dummy)
{
int i;
unsigned long flags, next_interval = jiffies + sysctl_tr_rif_timeout/2;
spin_lock_irqsave(&rif_lock, flags);
for(i =0; i < RIF_TABLE_SIZE; i++) {
struct rif_cache *entry, **pentry;
pentry = rif_table+i;
while((entry=*pentry) != NULL) {
unsigned long expires
= entry->last_used + sysctl_tr_rif_timeout;
if (time_before_eq(expires, jiffies)) {
*pentry = entry->next;
kfree(entry);
} else {
pentry = &entry->next;
if (time_before(expires, next_interval))
next_interval = expires;
}
}
}
spin_unlock_irqrestore(&rif_lock, flags);
mod_timer(&rif_timer, next_interval);
}
/*
* Generate the /proc/net information for the token ring RIF
* routing.
*/
#ifdef CONFIG_PROC_FS
static struct rif_cache *rif_get_idx(loff_t pos)
{
int i;
struct rif_cache *entry;
loff_t off = 0;
for(i = 0; i < RIF_TABLE_SIZE; i++)
for(entry = rif_table[i]; entry; entry = entry->next) {
if (off == pos)
return entry;
++off;
}
return NULL;
}
static void *rif_seq_start(struct seq_file *seq, loff_t *pos)
{
spin_lock_irq(&rif_lock);
return *pos ? rif_get_idx(*pos - 1) : SEQ_START_TOKEN;
}
static void *rif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
int i;
struct rif_cache *ent = v;
++*pos;
if (v == SEQ_START_TOKEN) {
i = -1;
goto scan;
}
if (ent->next)
return ent->next;
i = rif_hash(ent->addr);
scan:
while (++i < RIF_TABLE_SIZE) {
if ((ent = rif_table[i]) != NULL)
return ent;
}
return NULL;
}
static void rif_seq_stop(struct seq_file *seq, void *v)
{
spin_unlock_irq(&rif_lock);
}
static int rif_seq_show(struct seq_file *seq, void *v)
{
int j, rcf_len, segment, brdgnmb;
struct rif_cache *entry = v;
DECLARE_MAC_BUF(mac);
if (v == SEQ_START_TOKEN)
seq_puts(seq,
"if TR address TTL rcf routing segments\n");
else {
[NET]: Make the device list and device lookups per namespace. This patch makes most of the generic device layer network namespace safe. This patch makes dev_base_head a network namespace variable, and then it picks up a few associated variables. The functions: dev_getbyhwaddr dev_getfirsthwbytype dev_get_by_flags dev_get_by_name __dev_get_by_name dev_get_by_index __dev_get_by_index dev_ioctl dev_ethtool dev_load wireless_process_ioctl were modified to take a network namespace argument, and deal with it. vlan_ioctl_set and brioctl_set were modified so their hooks will receive a network namespace argument. So basically anthing in the core of the network stack that was affected to by the change of dev_base was modified to handle multiple network namespaces. The rest of the network stack was simply modified to explicitly use &init_net the initial network namespace. This can be fixed when those components of the network stack are modified to handle multiple network namespaces. For now the ifindex generator is left global. Fundametally ifindex numbers are per namespace, or else we will have corner case problems with migration when we get that far. At the same time there are assumptions in the network stack that the ifindex of a network device won't change. Making the ifindex number global seems a good compromise until the network stack can cope with ifindex changes when you change namespaces, and the like. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-17 18:56:21 +00:00
struct net_device *dev = dev_get_by_index(&init_net, entry->iface);
long ttl = (long) (entry->last_used + sysctl_tr_rif_timeout)
- (long) jiffies;
seq_printf(seq, "%s %s %7li ",
dev?dev->name:"?",
print_mac(mac, entry->addr),
ttl/HZ);
if (entry->local_ring)
seq_puts(seq, "local\n");
else {
seq_printf(seq, "%04X", ntohs(entry->rcf));
rcf_len = ((ntohs(entry->rcf) & TR_RCF_LEN_MASK)>>8)-2;
if (rcf_len)
rcf_len >>= 1;
for(j = 1; j < rcf_len; j++) {
if(j==1) {
segment=ntohs(entry->rseg[j-1])>>4;
seq_printf(seq," %03X",segment);
}
segment=ntohs(entry->rseg[j])>>4;
brdgnmb=ntohs(entry->rseg[j-1])&0x00f;
seq_printf(seq,"-%01X-%03X",brdgnmb,segment);
}
seq_putc(seq, '\n');
}
}
return 0;
}
static const struct seq_operations rif_seq_ops = {
.start = rif_seq_start,
.next = rif_seq_next,
.stop = rif_seq_stop,
.show = rif_seq_show,
};
static int rif_seq_open(struct inode *inode, struct file *file)
{
return seq_open(file, &rif_seq_ops);
}
static const struct file_operations rif_seq_fops = {
.owner = THIS_MODULE,
.open = rif_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#endif
static const struct header_ops tr_header_ops = {
.create = tr_header,
.rebuild= tr_rebuild_header,
};
static void tr_setup(struct net_device *dev)
{
/*
* Configure and register
*/
dev->header_ops = &tr_header_ops;
dev->type = ARPHRD_IEEE802_TR;
dev->hard_header_len = TR_HLEN;
dev->mtu = 2000;
dev->addr_len = TR_ALEN;
dev->tx_queue_len = 100; /* Long queues on tr */
memset(dev->broadcast,0xFF, TR_ALEN);
/* New-style flags. */
dev->flags = IFF_BROADCAST | IFF_MULTICAST ;
}
/**
* alloc_trdev - Register token ring device
* @sizeof_priv: Size of additional driver-private structure to be allocated
* for this token ring device
*
* Fill in the fields of the device structure with token ring-generic values.
*
* Constructs a new net device, complete with a private data area of
* size @sizeof_priv. A 32-byte (not bit) alignment is enforced for
* this private data area.
*/
struct net_device *alloc_trdev(int sizeof_priv)
{
return alloc_netdev(sizeof_priv, "tr%d", tr_setup);
}
/*
* Called during bootup. We don't actually have to initialise
* too much for this.
*/
static int __init rif_init(void)
{
init_timer(&rif_timer);
rif_timer.expires = jiffies + sysctl_tr_rif_timeout;
rif_timer.data = 0L;
rif_timer.function = rif_check_expire;
add_timer(&rif_timer);
proc_net_fops_create(&init_net, "tr_rif", S_IRUGO, &rif_seq_fops);
return 0;
}
module_init(rif_init);
EXPORT_SYMBOL(tr_type_trans);
EXPORT_SYMBOL(alloc_trdev);