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-rw-r--r--net/802/tr.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/net/802/tr.c b/net/802/tr.c
new file mode 100644
index 00000000000..85293ccf7ef
--- /dev/null
+++ b/net/802/tr.c
@@ -0,0 +1,645 @@
+/*
+ * 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/config.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>
+
+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_s {
+ unsigned char addr[TR_ALEN];
+ int iface;
+ __u16 rcf;
+ __u16 rseg[8];
+ struct rif_cache_s *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_s *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,
+ void *daddr, 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",(unsigned int)htons(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.
+ */
+
+unsigned short tr_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+
+ struct trh_hdr *trh=(struct trh_hdr *)skb->data;
+ struct trllc *trllc;
+ unsigned riflen=0;
+
+ skb->mac.raw = skb->data;
+
+ 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 == ntohs(ETH_P_IP) ||
+ trllc->ethertype == ntohs(ETH_P_IPV6) ||
+ trllc->ethertype == ntohs(ETH_P_ARP)))
+ {
+ skb_pull(skb, sizeof(struct trllc));
+ return trllc->ethertype;
+ }
+
+ return ntohs(ETH_P_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_s *entry;
+ unsigned char *olddata;
+ static const unsigned char mcast_func_addr[]
+ = {0xC0,0x00,0x00,0x04,0x00,0x00};
+
+ spin_lock_bh(&rif_lock);
+
+ /*
+ * 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
+printk("source routing for %02X:%02X:%02X:%02X:%02X:%02X\n",trh->daddr[0],
+ trh->daddr[1],trh->daddr[2],trh->daddr[3],trh->daddr[4],trh->daddr[5]);
+#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_bh(&rif_lock);
+
+ 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;
+ struct rif_cache_s *entry;
+
+
+ spin_lock_bh(&rif_lock);
+
+ /*
+ * 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
+printk("adding rif_entry: addr:%02X:%02X:%02X:%02X:%02X:%02X rcf:%04X\n",
+ trh->saddr[0],trh->saddr[1],trh->saddr[2],
+ trh->saddr[3],trh->saddr[4],trh->saddr[5],
+ 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_s),GFP_ATOMIC);
+
+ if(!entry)
+ {
+ printk(KERN_DEBUG "tr.c: Couldn't malloc rif cache entry !\n");
+ spin_unlock_bh(&rif_lock);
+ 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;
+ trh->saddr[0]|=TR_RII; /* put the routing indicator back for tcpdump */
+ }
+ 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
+printk("updating rif_entry: addr:%02X:%02X:%02X:%02X:%02X:%02X rcf:%04X\n",
+ trh->saddr[0],trh->saddr[1],trh->saddr[2],
+ trh->saddr[3],trh->saddr[4],trh->saddr[5],
+ 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;
+ }
+ spin_unlock_bh(&rif_lock);
+}
+
+/*
+ * 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 next_interval = jiffies + sysctl_tr_rif_timeout/2;
+
+ spin_lock_bh(&rif_lock);
+
+ for(i =0; i < RIF_TABLE_SIZE; i++) {
+ struct rif_cache_s *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_bh(&rif_lock);
+
+ 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_s *rif_get_idx(loff_t pos)
+{
+ int i;
+ struct rif_cache_s *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_bh(&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_s *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_bh(&rif_lock);
+}
+
+static int rif_seq_show(struct seq_file *seq, void *v)
+{
+ int j, rcf_len, segment, brdgnmb;
+ struct rif_cache_s *entry = v;
+
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq,
+ "if TR address TTL rcf routing segments\n");
+ else {
+ struct net_device *dev = dev_get_by_index(entry->iface);
+ long ttl = (long) (entry->last_used + sysctl_tr_rif_timeout)
+ - (long) jiffies;
+
+ seq_printf(seq, "%s %02X:%02X:%02X:%02X:%02X:%02X %7li ",
+ dev?dev->name:"?",
+ entry->addr[0],entry->addr[1],entry->addr[2],
+ entry->addr[3],entry->addr[4],entry->addr[5],
+ 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 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 struct file_operations rif_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = rif_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+#endif
+
+static void tr_setup(struct net_device *dev)
+{
+ /*
+ * Configure and register
+ */
+
+ dev->hard_header = tr_header;
+ dev->rebuild_header = tr_rebuild_header;
+
+ 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 = sysctl_tr_rif_timeout;
+ rif_timer.data = 0L;
+ rif_timer.function = rif_check_expire;
+ add_timer(&rif_timer);
+
+ proc_net_fops_create("tr_rif", S_IRUGO, &rif_seq_fops);
+ return 0;
+}
+
+module_init(rif_init);
+
+EXPORT_SYMBOL(tr_source_route);
+EXPORT_SYMBOL(tr_type_trans);
+EXPORT_SYMBOL(alloc_trdev);
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-20 05:06:11 +0000