diff options
Diffstat (limited to 'drivers/net/appletalk/ipddp.c')
-rw-r--r-- | drivers/net/appletalk/ipddp.c | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/drivers/net/appletalk/ipddp.c b/drivers/net/appletalk/ipddp.c new file mode 100644 index 000000000..d55853539 --- /dev/null +++ b/drivers/net/appletalk/ipddp.c @@ -0,0 +1,345 @@ +/* + * 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/compat.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 <linux/slab.h> +#include <net/route.h> +#include <linux/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; +static DEFINE_SPINLOCK(ipddp_route_lock); + +#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 netdev_tx_t ipddp_xmit(struct sk_buff *skb, + 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_siocdevprivate(struct net_device *dev, struct ifreq *ifr, + void __user *data, int cmd); + +static const struct net_device_ops ipddp_netdev_ops = { + .ndo_start_xmit = ipddp_xmit, + .ndo_siocdevprivate = ipddp_siocdevprivate, + .ndo_set_mac_address = eth_mac_addr, + .ndo_validate_addr = eth_validate_addr, +}; + +static struct net_device * __init ipddp_init(void) +{ + static unsigned version_printed; + struct net_device *dev; + int err; + + dev = alloc_etherdev(0); + if (!dev) + return ERR_PTR(-ENOMEM); + + netif_keep_dst(dev); + strcpy(dev->name, "ipddp%d"); + + if (version_printed++ == 0) + printk(version); + + /* Initialize the device structure. */ + dev->netdev_ops = &ipddp_netdev_ops; + + 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; +} + + +/* + * Transmit LLAP/ELAP frame using aarp_send_ddp. + */ +static netdev_tx_t ipddp_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct rtable *rtable = skb_rtable(skb); + __be32 paddr = 0; + struct ddpehdr *ddp; + struct ipddp_route *rt; + struct atalk_addr *our_addr; + + if (rtable->rt_gw_family == AF_INET) + paddr = rtable->rt_gw4; + + spin_lock(&ipddp_route_lock); + + /* + * 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) { + spin_unlock(&ipddp_route_lock); + return NETDEV_TX_OK; + } + + 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_hops = htons(skb->len + (1<<10)); + 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 */ + + skb->protocol = htons(ETH_P_ATALK); /* Protocol has changed */ + + dev->stats.tx_packets++; + dev->stats.tx_bytes += skb->len; + + aarp_send_ddp(rt->dev, skb, &rt->at, NULL); + + spin_unlock(&ipddp_route_lock); + + return NETDEV_TX_OK; +} + +/* + * 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 = kzalloc(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; + } + + spin_lock_bh(&ipddp_route_lock); + if (__ipddp_find_route(rt)) { + spin_unlock_bh(&ipddp_route_lock); + kfree(rt); + return -EEXIST; + } + + rt->next = ipddp_route_list; + ipddp_route_list = rt; + + spin_unlock_bh(&ipddp_route_lock); + + 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; + + spin_lock_bh(&ipddp_route_lock); + 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; + spin_unlock_bh(&ipddp_route_lock); + kfree(tmp); + return 0; + } + r = &tmp->next; + } + + spin_unlock_bh(&ipddp_route_lock); + 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_siocdevprivate(struct net_device *dev, struct ifreq *ifr, + void __user *data, int cmd) +{ + struct ipddp_route rcp, rcp2, *rp; + + if (in_compat_syscall()) + return -EOPNOTSUPP; + + if(!capable(CAP_NET_ADMIN)) + return -EPERM; + + if (copy_from_user(&rcp, data, sizeof(rcp))) + return -EFAULT; + + switch(cmd) + { + case SIOCADDIPDDPRT: + return ipddp_create(&rcp); + + case SIOCFINDIPDDPRT: + spin_lock_bh(&ipddp_route_lock); + rp = __ipddp_find_route(&rcp); + if (rp) { + memset(&rcp2, 0, sizeof(rcp2)); + rcp2.ip = rp->ip; + rcp2.at = rp->at; + rcp2.flags = rp->flags; + } + spin_unlock_bh(&ipddp_route_lock); + + if (rp) { + if (copy_to_user(data, &rcp2, + sizeof(struct ipddp_route))) + return -EFAULT; + return 0; + } else + return -ENOENT; + + 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(); + return PTR_ERR_OR_ZERO(dev_ipddp); +} + +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); |