--- /dev/null
+/*
+ * 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/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 <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;
+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_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
+
+static const struct net_device_ops ipddp_netdev_ops = {
+ .ndo_start_xmit = ipddp_xmit,
+ .ndo_do_ioctl = ipddp_ioctl,
+ .ndo_change_mtu = eth_change_mtu,
+ .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)
+{
+ __be32 paddr = skb_rtable(skb)->rt_gateway;
+ struct ddpehdr *ddp;
+ struct ipddp_route *rt;
+ struct atalk_addr *our_addr;
+
+ 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 = 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;
+ }
+
+ 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_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+ struct ipddp_route __user *rt = ifr->ifr_data;
+ struct ipddp_route rcp, rcp2, *rp;
+
+ 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:
+ spin_lock_bh(&ipddp_route_lock);
+ rp = __ipddp_find_route(&rcp);
+ if (rp)
+ memcpy(&rcp2, rp, sizeof(rcp2));
+ spin_unlock_bh(&ipddp_route_lock);
+
+ if (rp) {
+ if (copy_to_user(rt, &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();
+ 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);
Code Review / kvmfornfv.git / blobdiff