diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/802/tr.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/802/tr.c')
-rw-r--r-- | net/802/tr.c | 645 |
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); |