| /* |
| * ipddp.c: IP to Appletalk-IP Encapsulation driver for Linux |
| * Appletalk-IP to IP Decapsulation driver for Linux |
| * |
| * Authors: |
| * - DDP-IP Encap by: Bradford W. Johnson <johns393@maroon.tc.umn.edu> |
| * - DDP-IP Decap by: Jay Schulist <jschlst@samba.org> |
| * |
| * Derived from: |
| * - Almost all code already existed in net/appletalk/ddp.c I just |
| * moved/reorginized it into a driver file. Original IP-over-DDP code |
| * was done by Bradford W. Johnson <johns393@maroon.tc.umn.edu> |
| * - skeleton.c: A network driver outline for linux. |
| * Written 1993-94 by Donald Becker. |
| * - dummy.c: A dummy net driver. By Nick Holloway. |
| * - MacGate: A user space Daemon for Appletalk-IP Decap for |
| * Linux by Jay Schulist <jschlst@samba.org> |
| * |
| * Copyright 1993 United States Government as represented by the |
| * Director, National Security Agency. |
| * |
| * This software may be used and distributed according to the terms |
| * of the GNU General Public License, incorporated herein by reference. |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/ip.h> |
| #include <linux/atalk.h> |
| #include <linux/if_arp.h> |
| #include <net/route.h> |
| #include <asm/uaccess.h> |
| |
| #include "ipddp.h" /* Our stuff */ |
| |
| static const char version[] = KERN_INFO "ipddp.c:v0.01 8/28/97 Bradford W. Johnson <johns393@maroon.tc.umn.edu>\n"; |
| |
| static struct ipddp_route *ipddp_route_list; |
| |
| #ifdef CONFIG_IPDDP_ENCAP |
| static int ipddp_mode = IPDDP_ENCAP; |
| #else |
| static int ipddp_mode = IPDDP_DECAP; |
| #endif |
| |
| /* Index to functions, as function prototypes. */ |
| static int ipddp_xmit(struct sk_buff *skb, struct net_device *dev); |
| static struct net_device_stats *ipddp_get_stats(struct net_device *dev); |
| static int ipddp_create(struct ipddp_route *new_rt); |
| static int ipddp_delete(struct ipddp_route *rt); |
| static struct ipddp_route* ipddp_find_route(struct ipddp_route *rt); |
| static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd); |
| |
| |
| static struct net_device * __init ipddp_init(void) |
| { |
| static unsigned version_printed; |
| struct net_device *dev; |
| int err; |
| |
| dev = alloc_etherdev(sizeof(struct net_device_stats)); |
| if (!dev) |
| return ERR_PTR(-ENOMEM); |
| |
| SET_MODULE_OWNER(dev); |
| strcpy(dev->name, "ipddp%d"); |
| |
| if (version_printed++ == 0) |
| printk(version); |
| |
| /* Initalize the device structure. */ |
| dev->hard_start_xmit = ipddp_xmit; |
| dev->get_stats = ipddp_get_stats; |
| dev->do_ioctl = ipddp_ioctl; |
| |
| dev->type = ARPHRD_IPDDP; /* IP over DDP tunnel */ |
| dev->mtu = 585; |
| dev->flags |= IFF_NOARP; |
| |
| /* |
| * The worst case header we will need is currently a |
| * ethernet header (14 bytes) and a ddp header (sizeof ddpehdr+1) |
| * We send over SNAP so that takes another 8 bytes. |
| */ |
| dev->hard_header_len = 14+8+sizeof(struct ddpehdr)+1; |
| |
| err = register_netdev(dev); |
| if (err) { |
| free_netdev(dev); |
| return ERR_PTR(err); |
| } |
| |
| /* Let the user now what mode we are in */ |
| if(ipddp_mode == IPDDP_ENCAP) |
| printk("%s: Appletalk-IP Encap. mode by Bradford W. Johnson <johns393@maroon.tc.umn.edu>\n", |
| dev->name); |
| if(ipddp_mode == IPDDP_DECAP) |
| printk("%s: Appletalk-IP Decap. mode by Jay Schulist <jschlst@samba.org>\n", |
| dev->name); |
| |
| return dev; |
| } |
| |
| /* |
| * Get the current statistics. This may be called with the card open or closed. |
| */ |
| static struct net_device_stats *ipddp_get_stats(struct net_device *dev) |
| { |
| return dev->priv; |
| } |
| |
| /* |
| * Transmit LLAP/ELAP frame using aarp_send_ddp. |
| */ |
| static int ipddp_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| u32 paddr = ((struct rtable*)skb->dst)->rt_gateway; |
| struct ddpehdr *ddp; |
| struct ipddp_route *rt; |
| struct atalk_addr *our_addr; |
| |
| /* |
| * Find appropriate route to use, based only on IP number. |
| */ |
| for(rt = ipddp_route_list; rt != NULL; rt = rt->next) |
| { |
| if(rt->ip == paddr) |
| break; |
| } |
| if(rt == NULL) |
| return 0; |
| |
| our_addr = atalk_find_dev_addr(rt->dev); |
| |
| if(ipddp_mode == IPDDP_DECAP) |
| /* |
| * Pull off the excess room that should not be there. |
| * This is due to a hard-header problem. This is the |
| * quick fix for now though, till it breaks. |
| */ |
| skb_pull(skb, 35-(sizeof(struct ddpehdr)+1)); |
| |
| /* Create the Extended DDP header */ |
| ddp = (struct ddpehdr *)skb->data; |
| ddp->deh_len = skb->len; |
| ddp->deh_hops = 1; |
| ddp->deh_pad = 0; |
| ddp->deh_sum = 0; |
| |
| /* |
| * For Localtalk we need aarp_send_ddp to strip the |
| * long DDP header and place a shot DDP header on it. |
| */ |
| if(rt->dev->type == ARPHRD_LOCALTLK) |
| { |
| ddp->deh_dnet = 0; /* FIXME more hops?? */ |
| ddp->deh_snet = 0; |
| } |
| else |
| { |
| ddp->deh_dnet = rt->at.s_net; /* FIXME more hops?? */ |
| ddp->deh_snet = our_addr->s_net; |
| } |
| ddp->deh_dnode = rt->at.s_node; |
| ddp->deh_snode = our_addr->s_node; |
| ddp->deh_dport = 72; |
| ddp->deh_sport = 72; |
| |
| *((__u8 *)(ddp+1)) = 22; /* ddp type = IP */ |
| *((__u16 *)ddp)=ntohs(*((__u16 *)ddp)); /* fix up length field */ |
| |
| skb->protocol = htons(ETH_P_ATALK); /* Protocol has changed */ |
| |
| ((struct net_device_stats *) dev->priv)->tx_packets++; |
| ((struct net_device_stats *) dev->priv)->tx_bytes+=skb->len; |
| |
| if(aarp_send_ddp(rt->dev, skb, &rt->at, NULL) < 0) |
| dev_kfree_skb(skb); |
| |
| return 0; |
| } |
| |
| /* |
| * Create a routing entry. We first verify that the |
| * record does not already exist. If it does we return -EEXIST |
| */ |
| static int ipddp_create(struct ipddp_route *new_rt) |
| { |
| struct ipddp_route *rt =(struct ipddp_route*) kmalloc(sizeof(*rt), GFP_KERNEL); |
| |
| if (rt == NULL) |
| return -ENOMEM; |
| |
| rt->ip = new_rt->ip; |
| rt->at = new_rt->at; |
| rt->next = NULL; |
| if ((rt->dev = atrtr_get_dev(&rt->at)) == NULL) { |
| kfree(rt); |
| return -ENETUNREACH; |
| } |
| |
| if (ipddp_find_route(rt)) { |
| kfree(rt); |
| return -EEXIST; |
| } |
| |
| rt->next = ipddp_route_list; |
| ipddp_route_list = rt; |
| |
| return 0; |
| } |
| |
| /* |
| * Delete a route, we only delete a FULL match. |
| * If route does not exist we return -ENOENT. |
| */ |
| static int ipddp_delete(struct ipddp_route *rt) |
| { |
| struct ipddp_route **r = &ipddp_route_list; |
| struct ipddp_route *tmp; |
| |
| while((tmp = *r) != NULL) |
| { |
| if(tmp->ip == rt->ip |
| && tmp->at.s_net == rt->at.s_net |
| && tmp->at.s_node == rt->at.s_node) |
| { |
| *r = tmp->next; |
| kfree(tmp); |
| return 0; |
| } |
| r = &tmp->next; |
| } |
| |
| return (-ENOENT); |
| } |
| |
| /* |
| * Find a routing entry, we only return a FULL match |
| */ |
| static struct ipddp_route* ipddp_find_route(struct ipddp_route *rt) |
| { |
| struct ipddp_route *f; |
| |
| for(f = ipddp_route_list; f != NULL; f = f->next) |
| { |
| if(f->ip == rt->ip |
| && f->at.s_net == rt->at.s_net |
| && f->at.s_node == rt->at.s_node) |
| return (f); |
| } |
| |
| return (NULL); |
| } |
| |
| static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
| { |
| struct ipddp_route __user *rt = ifr->ifr_data; |
| struct ipddp_route rcp; |
| |
| if(!capable(CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| if(copy_from_user(&rcp, rt, sizeof(rcp))) |
| return -EFAULT; |
| |
| switch(cmd) |
| { |
| case SIOCADDIPDDPRT: |
| return (ipddp_create(&rcp)); |
| |
| case SIOCFINDIPDDPRT: |
| if(copy_to_user(rt, ipddp_find_route(&rcp), sizeof(struct ipddp_route))) |
| return -EFAULT; |
| return 0; |
| |
| case SIOCDELIPDDPRT: |
| return (ipddp_delete(&rcp)); |
| |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static struct net_device *dev_ipddp; |
| |
| MODULE_LICENSE("GPL"); |
| module_param(ipddp_mode, int, 0); |
| |
| static int __init ipddp_init_module(void) |
| { |
| dev_ipddp = ipddp_init(); |
| if (IS_ERR(dev_ipddp)) |
| return PTR_ERR(dev_ipddp); |
| return 0; |
| } |
| |
| static void __exit ipddp_cleanup_module(void) |
| { |
| struct ipddp_route *p; |
| |
| unregister_netdev(dev_ipddp); |
| free_netdev(dev_ipddp); |
| |
| while (ipddp_route_list) { |
| p = ipddp_route_list->next; |
| kfree(ipddp_route_list); |
| ipddp_route_list = p; |
| } |
| } |
| |
| module_init(ipddp_init_module); |
| module_exit(ipddp_cleanup_module); |
