| /* |
| * 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/types.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.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/init.h> |
| #include <net/arp.h> |
| |
| static void tr_source_route(struct sk_buff *skb, struct trh_hdr *trh, struct net_device *dev); |
| 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 |
| |
| typedef struct rif_cache_s *rif_cache; |
| |
| /* |
| * 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]; |
| 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. |
| */ |
| |
| rif_cache rif_table[RIF_TABLE_SIZE]={ NULL, }; |
| |
| static spinlock_t rif_lock = SPIN_LOCK_UNLOCKED; |
| |
| #define RIF_TIMEOUT 60*10*HZ |
| #define RIF_CHECK_INTERVAL 60*HZ |
| |
| /* |
| * Garbage disposal timer. |
| */ |
| |
| static struct timer_list rif_timer; |
| |
| int sysctl_tr_rif_timeout = RIF_TIMEOUT; |
| |
| /* |
| * Put the headers on a token ring packet. Token ring source routing |
| * makes this a little more exciting than on ethernet. |
| */ |
| |
| 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 code calls |
| * dev->hard_header directly. |
| */ |
| if (type == ETH_P_IP || type == ETH_P_ARP) |
| { |
| struct trllc *trllc=(struct trllc *)(trh+1); |
| |
| 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. |
| */ |
| |
| 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_ARP))) |
| { |
| skb_pull(skb, sizeof(struct trllc)); |
| return trllc->ethertype; |
| } |
| |
| return ntohs(ETH_P_802_2); |
| } |
| |
| /* |
| * We try to do source routing... |
| */ |
| |
| static void tr_source_route(struct sk_buff *skb,struct trh_hdr *trh,struct net_device *dev) |
| { |
| int i, slack; |
| unsigned int hash; |
| rif_cache entry; |
| unsigned char *olddata; |
| unsigned char mcast_func_addr[] = {0xC0,0x00,0x00,0x04,0x00,0x00}; |
| unsigned long flags ; |
| |
| 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 |
| { |
| for(i=0,hash=0;i<TR_ALEN;hash+=trh->daddr[i++]); |
| hash&=RIF_TABLE_SIZE-1; |
| /* |
| * 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_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) |
| { |
| int i; |
| unsigned int hash, rii_p = 0; |
| rif_cache 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; |
| } |
| } |
| |
| for(i=0,hash=0;i<TR_ALEN;hash+=trh->saddr[i++]); |
| hash&=RIF_TABLE_SIZE-1; |
| 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 now=jiffies; |
| unsigned long flags ; |
| |
| spin_lock_irqsave(&rif_lock,flags); |
| |
| for(i=0; i < RIF_TABLE_SIZE;i++) |
| { |
| rif_cache entry, *pentry=rif_table+i; |
| while((entry=*pentry)) |
| { |
| /* |
| * Out it goes |
| */ |
| if((now-entry->last_used) > sysctl_tr_rif_timeout) |
| { |
| *pentry=entry->next; |
| kfree(entry); |
| } |
| else |
| pentry=&entry->next; |
| } |
| } |
| |
| spin_unlock_irqrestore(&rif_lock,flags); |
| |
| /* |
| * Reset the timer |
| */ |
| |
| mod_timer(&rif_timer, jiffies+sysctl_tr_rif_timeout); |
| |
| } |
| |
| /* |
| * Generate the /proc/net information for the token ring RIF |
| * routing. |
| */ |
| |
| #ifndef CONFIG_PROC_FS |
| static int rif_get_info(char *buffer,char **start, off_t offset, int length) { return 0;} |
| #else |
| static int rif_get_info(char *buffer,char **start, off_t offset, int length) |
| { |
| int len=0; |
| off_t begin=0; |
| off_t pos=0; |
| int size,i,j,rcf_len,segment,brdgnmb; |
| unsigned long now=jiffies; |
| |
| rif_cache entry; |
| |
| size=sprintf(buffer, |
| "if TR address TTL rcf routing segments\n"); |
| pos+=size; |
| len+=size; |
| |
| spin_lock_bh(&rif_lock); |
| for(i=0;i < RIF_TABLE_SIZE;i++) |
| { |
| for(entry=rif_table[i];entry;entry=entry->next) { |
| struct net_device *dev = __dev_get_by_index(entry->iface); |
| |
| size=sprintf(buffer+len,"%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], |
| sysctl_tr_rif_timeout-(now-entry->last_used)); |
| len+=size; |
| pos=begin+len; |
| if (entry->local_ring) |
| size=sprintf(buffer+len,"local\n"); |
| else { |
| size=sprintf(buffer+len,"%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; |
| len+=size; |
| pos=begin+len; |
| size=sprintf(buffer+len," %03X",segment); |
| }; |
| segment=ntohs(entry->rseg[j])>>4; |
| brdgnmb=ntohs(entry->rseg[j-1])&0x00f; |
| len+=size; |
| pos=begin+len; |
| size=sprintf(buffer+len,"-%01X-%03X",brdgnmb,segment); |
| } |
| len+=size; |
| pos=begin+len; |
| size=sprintf(buffer+len,"\n"); |
| } |
| len+=size; |
| pos=begin+len; |
| |
| if(pos<offset) |
| { |
| len=0; |
| begin=pos; |
| } |
| if(pos>offset+length) |
| break; |
| } |
| if(pos>offset+length) |
| break; |
| } |
| spin_unlock_bh(&rif_lock); |
| |
| *start=buffer+(offset-begin); /* Start of wanted data */ |
| len-=(offset-begin); /* Start slop */ |
| if(len>length) |
| len=length; /* Ending slop */ |
| if (len<0) |
| len=0; |
| return len; |
| } |
| #endif |
| |
| /* |
| * Called during bootup. We don't actually have to initialise |
| * too much for this. |
| */ |
| |
| static int __init rif_init(void) |
| { |
| rif_timer.expires = RIF_TIMEOUT; |
| rif_timer.data = 0L; |
| rif_timer.function = rif_check_expire; |
| init_timer(&rif_timer); |
| add_timer(&rif_timer); |
| |
| proc_net_create("tr_rif",0,rif_get_info); |
| return 0; |
| } |
| |
| module_init(rif_init); |