| /* |
| * 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 <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 <linux/sysctl.h> |
| #include <linux/slab.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; |
| |
| static 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 int 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 int 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 |
| printk("source routing for %pM\n", 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 |
| printk("adding rif_entry: addr:%pM rcf:%04X\n", |
| 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 |
| printk("updating rif_entry: addr:%pM rcf:%04X\n", |
| 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) |
| __acquires(&rif_lock) |
| { |
| 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) |
| __releases(&rif_lock) |
| { |
| 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; |
| |
| 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(&init_net, entry->iface); |
| long ttl = (long) (entry->last_used + sysctl_tr_rif_timeout) |
| - (long) jiffies; |
| |
| seq_printf(seq, "%s %pM %7li ", |
| dev?dev->name:"?", |
| 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'); |
| } |
| |
| if (dev) |
| dev_put(dev); |
| } |
| 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); |
| } |
| |
| #ifdef CONFIG_SYSCTL |
| static struct ctl_table tr_table[] = { |
| { |
| .procname = "rif_timeout", |
| .data = &sysctl_tr_rif_timeout, |
| .maxlen = sizeof(int), |
| .mode = 0644, |
| .proc_handler = proc_dointvec |
| }, |
| { }, |
| }; |
| |
| static __initdata struct ctl_path tr_path[] = { |
| { .procname = "net", }, |
| { .procname = "token-ring", }, |
| { } |
| }; |
| #endif |
| |
| /* |
| * Called during bootup. We don't actually have to initialise |
| * too much for this. |
| */ |
| |
| static int __init rif_init(void) |
| { |
| rif_timer.expires = jiffies + sysctl_tr_rif_timeout; |
| setup_timer(&rif_timer, rif_check_expire, 0); |
| add_timer(&rif_timer); |
| #ifdef CONFIG_SYSCTL |
| register_sysctl_paths(tr_path, tr_table); |
| #endif |
| 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); |
| |
| MODULE_LICENSE("GPL"); |