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5d9c5a3292
Now that we always zero the IPCB->opts in ip_rcv, it is no longer necessary to do so before calling netif_rx for tunneled packets. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
925 lines
22 KiB
C
925 lines
22 KiB
C
/*
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* Linux NET3: IP/IP protocol decoder.
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*
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* Version: $Id: ipip.c,v 1.50 2001/10/02 02:22:36 davem Exp $
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*
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* Authors:
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* Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
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*
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* Fixes:
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* Alan Cox : Merged and made usable non modular (its so tiny its silly as
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* a module taking up 2 pages).
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* Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
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* to keep ip_forward happy.
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* Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
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* Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL
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* David Woodhouse : Perform some basic ICMP handling.
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* IPIP Routing without decapsulation.
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* Carlos Picoto : GRE over IP support
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* Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
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* I do not want to merge them together.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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*/
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/* tunnel.c: an IP tunnel driver
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The purpose of this driver is to provide an IP tunnel through
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which you can tunnel network traffic transparently across subnets.
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This was written by looking at Nick Holloway's dummy driver
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Thanks for the great code!
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-Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
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Minor tweaks:
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Cleaned up the code a little and added some pre-1.3.0 tweaks.
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dev->hard_header/hard_header_len changed to use no headers.
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Comments/bracketing tweaked.
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Made the tunnels use dev->name not tunnel: when error reporting.
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Added tx_dropped stat
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-Alan Cox (Alan.Cox@linux.org) 21 March 95
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Reworked:
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Changed to tunnel to destination gateway in addition to the
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tunnel's pointopoint address
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Almost completely rewritten
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Note: There is currently no firewall or ICMP handling done.
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-Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96
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*/
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/* Things I wish I had known when writing the tunnel driver:
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When the tunnel_xmit() function is called, the skb contains the
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packet to be sent (plus a great deal of extra info), and dev
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contains the tunnel device that _we_ are.
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When we are passed a packet, we are expected to fill in the
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source address with our source IP address.
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What is the proper way to allocate, copy and free a buffer?
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After you allocate it, it is a "0 length" chunk of memory
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starting at zero. If you want to add headers to the buffer
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later, you'll have to call "skb_reserve(skb, amount)" with
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the amount of memory you want reserved. Then, you call
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"skb_put(skb, amount)" with the amount of space you want in
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the buffer. skb_put() returns a pointer to the top (#0) of
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that buffer. skb->len is set to the amount of space you have
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"allocated" with skb_put(). You can then write up to skb->len
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bytes to that buffer. If you need more, you can call skb_put()
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again with the additional amount of space you need. You can
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find out how much more space you can allocate by calling
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"skb_tailroom(skb)".
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Now, to add header space, call "skb_push(skb, header_len)".
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This creates space at the beginning of the buffer and returns
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a pointer to this new space. If later you need to strip a
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header from a buffer, call "skb_pull(skb, header_len)".
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skb_headroom() will return how much space is left at the top
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of the buffer (before the main data). Remember, this headroom
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space must be reserved before the skb_put() function is called.
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*/
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/*
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This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
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For comments look at net/ipv4/ip_gre.c --ANK
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*/
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#include <linux/capability.h>
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <asm/uaccess.h>
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#include <linux/skbuff.h>
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#include <linux/netdevice.h>
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#include <linux/in.h>
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/if_arp.h>
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#include <linux/mroute.h>
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#include <linux/init.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/if_ether.h>
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#include <net/sock.h>
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#include <net/ip.h>
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#include <net/icmp.h>
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#include <net/ipip.h>
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#include <net/inet_ecn.h>
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#include <net/xfrm.h>
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#define HASH_SIZE 16
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#define HASH(addr) ((addr^(addr>>4))&0xF)
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static int ipip_fb_tunnel_init(struct net_device *dev);
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static int ipip_tunnel_init(struct net_device *dev);
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static void ipip_tunnel_setup(struct net_device *dev);
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static struct net_device *ipip_fb_tunnel_dev;
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static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
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static struct ip_tunnel *tunnels_r[HASH_SIZE];
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static struct ip_tunnel *tunnels_l[HASH_SIZE];
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static struct ip_tunnel *tunnels_wc[1];
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static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
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static DEFINE_RWLOCK(ipip_lock);
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static struct ip_tunnel * ipip_tunnel_lookup(u32 remote, u32 local)
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{
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unsigned h0 = HASH(remote);
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unsigned h1 = HASH(local);
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struct ip_tunnel *t;
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for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
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if (local == t->parms.iph.saddr &&
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remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
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return t;
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}
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for (t = tunnels_r[h0]; t; t = t->next) {
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if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
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return t;
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}
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for (t = tunnels_l[h1]; t; t = t->next) {
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if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
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return t;
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}
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if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
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return t;
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return NULL;
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}
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static struct ip_tunnel **ipip_bucket(struct ip_tunnel *t)
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{
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u32 remote = t->parms.iph.daddr;
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u32 local = t->parms.iph.saddr;
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unsigned h = 0;
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int prio = 0;
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if (remote) {
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prio |= 2;
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h ^= HASH(remote);
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}
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if (local) {
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prio |= 1;
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h ^= HASH(local);
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}
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return &tunnels[prio][h];
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}
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static void ipip_tunnel_unlink(struct ip_tunnel *t)
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{
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struct ip_tunnel **tp;
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for (tp = ipip_bucket(t); *tp; tp = &(*tp)->next) {
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if (t == *tp) {
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write_lock_bh(&ipip_lock);
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*tp = t->next;
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write_unlock_bh(&ipip_lock);
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break;
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}
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}
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}
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static void ipip_tunnel_link(struct ip_tunnel *t)
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{
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struct ip_tunnel **tp = ipip_bucket(t);
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t->next = *tp;
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write_lock_bh(&ipip_lock);
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*tp = t;
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write_unlock_bh(&ipip_lock);
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}
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static struct ip_tunnel * ipip_tunnel_locate(struct ip_tunnel_parm *parms, int create)
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{
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u32 remote = parms->iph.daddr;
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u32 local = parms->iph.saddr;
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struct ip_tunnel *t, **tp, *nt;
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struct net_device *dev;
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unsigned h = 0;
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int prio = 0;
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char name[IFNAMSIZ];
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if (remote) {
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prio |= 2;
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h ^= HASH(remote);
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}
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if (local) {
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prio |= 1;
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h ^= HASH(local);
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}
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for (tp = &tunnels[prio][h]; (t = *tp) != NULL; tp = &t->next) {
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if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
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return t;
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}
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if (!create)
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return NULL;
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if (parms->name[0])
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strlcpy(name, parms->name, IFNAMSIZ);
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else {
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int i;
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for (i=1; i<100; i++) {
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sprintf(name, "tunl%d", i);
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if (__dev_get_by_name(name) == NULL)
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break;
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}
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if (i==100)
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goto failed;
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}
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dev = alloc_netdev(sizeof(*t), name, ipip_tunnel_setup);
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if (dev == NULL)
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return NULL;
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nt = netdev_priv(dev);
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SET_MODULE_OWNER(dev);
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dev->init = ipip_tunnel_init;
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nt->parms = *parms;
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if (register_netdevice(dev) < 0) {
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free_netdev(dev);
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goto failed;
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}
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dev_hold(dev);
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ipip_tunnel_link(nt);
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return nt;
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failed:
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return NULL;
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}
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static void ipip_tunnel_uninit(struct net_device *dev)
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{
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if (dev == ipip_fb_tunnel_dev) {
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write_lock_bh(&ipip_lock);
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tunnels_wc[0] = NULL;
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write_unlock_bh(&ipip_lock);
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} else
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ipip_tunnel_unlink(netdev_priv(dev));
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dev_put(dev);
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}
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static int ipip_err(struct sk_buff *skb, u32 info)
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{
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#ifndef I_WISH_WORLD_WERE_PERFECT
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/* It is not :-( All the routers (except for Linux) return only
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8 bytes of packet payload. It means, that precise relaying of
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ICMP in the real Internet is absolutely infeasible.
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*/
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struct iphdr *iph = (struct iphdr*)skb->data;
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int type = skb->h.icmph->type;
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int code = skb->h.icmph->code;
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struct ip_tunnel *t;
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int err;
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switch (type) {
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default:
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case ICMP_PARAMETERPROB:
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return 0;
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case ICMP_DEST_UNREACH:
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switch (code) {
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case ICMP_SR_FAILED:
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case ICMP_PORT_UNREACH:
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/* Impossible event. */
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return 0;
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case ICMP_FRAG_NEEDED:
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/* Soft state for pmtu is maintained by IP core. */
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return 0;
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default:
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/* All others are translated to HOST_UNREACH.
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rfc2003 contains "deep thoughts" about NET_UNREACH,
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I believe they are just ether pollution. --ANK
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*/
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break;
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}
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break;
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case ICMP_TIME_EXCEEDED:
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if (code != ICMP_EXC_TTL)
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return 0;
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break;
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}
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err = -ENOENT;
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read_lock(&ipip_lock);
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t = ipip_tunnel_lookup(iph->daddr, iph->saddr);
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if (t == NULL || t->parms.iph.daddr == 0)
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goto out;
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err = 0;
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if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
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goto out;
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if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
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t->err_count++;
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else
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t->err_count = 1;
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t->err_time = jiffies;
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out:
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read_unlock(&ipip_lock);
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return err;
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#else
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struct iphdr *iph = (struct iphdr*)dp;
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int hlen = iph->ihl<<2;
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struct iphdr *eiph;
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int type = skb->h.icmph->type;
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int code = skb->h.icmph->code;
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int rel_type = 0;
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int rel_code = 0;
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int rel_info = 0;
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struct sk_buff *skb2;
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struct flowi fl;
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struct rtable *rt;
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if (len < hlen + sizeof(struct iphdr))
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return 0;
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eiph = (struct iphdr*)(dp + hlen);
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switch (type) {
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default:
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return 0;
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case ICMP_PARAMETERPROB:
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if (skb->h.icmph->un.gateway < hlen)
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return 0;
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/* So... This guy found something strange INSIDE encapsulated
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packet. Well, he is fool, but what can we do ?
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*/
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rel_type = ICMP_PARAMETERPROB;
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rel_info = skb->h.icmph->un.gateway - hlen;
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break;
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case ICMP_DEST_UNREACH:
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switch (code) {
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case ICMP_SR_FAILED:
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case ICMP_PORT_UNREACH:
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/* Impossible event. */
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return 0;
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case ICMP_FRAG_NEEDED:
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/* And it is the only really necessary thing :-) */
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rel_info = ntohs(skb->h.icmph->un.frag.mtu);
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if (rel_info < hlen+68)
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return 0;
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rel_info -= hlen;
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/* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */
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if (rel_info > ntohs(eiph->tot_len))
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return 0;
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break;
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default:
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/* All others are translated to HOST_UNREACH.
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rfc2003 contains "deep thoughts" about NET_UNREACH,
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I believe, it is just ether pollution. --ANK
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*/
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rel_type = ICMP_DEST_UNREACH;
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rel_code = ICMP_HOST_UNREACH;
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break;
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}
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break;
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case ICMP_TIME_EXCEEDED:
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if (code != ICMP_EXC_TTL)
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return 0;
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break;
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}
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/* Prepare fake skb to feed it to icmp_send */
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skb2 = skb_clone(skb, GFP_ATOMIC);
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if (skb2 == NULL)
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return 0;
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dst_release(skb2->dst);
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skb2->dst = NULL;
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skb_pull(skb2, skb->data - (u8*)eiph);
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skb2->nh.raw = skb2->data;
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/* Try to guess incoming interface */
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memset(&fl, 0, sizeof(fl));
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fl.fl4_daddr = eiph->saddr;
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fl.fl4_tos = RT_TOS(eiph->tos);
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fl.proto = IPPROTO_IPIP;
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if (ip_route_output_key(&rt, &key)) {
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kfree_skb(skb2);
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return 0;
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}
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skb2->dev = rt->u.dst.dev;
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/* route "incoming" packet */
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if (rt->rt_flags&RTCF_LOCAL) {
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ip_rt_put(rt);
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rt = NULL;
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fl.fl4_daddr = eiph->daddr;
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fl.fl4_src = eiph->saddr;
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fl.fl4_tos = eiph->tos;
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if (ip_route_output_key(&rt, &fl) ||
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rt->u.dst.dev->type != ARPHRD_TUNNEL) {
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ip_rt_put(rt);
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kfree_skb(skb2);
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return 0;
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}
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} else {
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ip_rt_put(rt);
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if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) ||
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skb2->dst->dev->type != ARPHRD_TUNNEL) {
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kfree_skb(skb2);
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return 0;
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}
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}
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/* change mtu on this route */
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if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
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if (rel_info > dst_mtu(skb2->dst)) {
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kfree_skb(skb2);
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return 0;
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}
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skb2->dst->ops->update_pmtu(skb2->dst, rel_info);
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rel_info = htonl(rel_info);
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} else if (type == ICMP_TIME_EXCEEDED) {
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struct ip_tunnel *t = netdev_priv(skb2->dev);
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if (t->parms.iph.ttl) {
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rel_type = ICMP_DEST_UNREACH;
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rel_code = ICMP_HOST_UNREACH;
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}
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}
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icmp_send(skb2, rel_type, rel_code, rel_info);
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kfree_skb(skb2);
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return 0;
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#endif
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}
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static inline void ipip_ecn_decapsulate(struct iphdr *outer_iph, struct sk_buff *skb)
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{
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struct iphdr *inner_iph = skb->nh.iph;
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if (INET_ECN_is_ce(outer_iph->tos))
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IP_ECN_set_ce(inner_iph);
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}
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static int ipip_rcv(struct sk_buff *skb)
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{
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struct iphdr *iph;
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struct ip_tunnel *tunnel;
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iph = skb->nh.iph;
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read_lock(&ipip_lock);
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if ((tunnel = ipip_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
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if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
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read_unlock(&ipip_lock);
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kfree_skb(skb);
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return 0;
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}
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secpath_reset(skb);
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skb->mac.raw = skb->nh.raw;
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skb->nh.raw = skb->data;
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skb->protocol = htons(ETH_P_IP);
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skb->pkt_type = PACKET_HOST;
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tunnel->stat.rx_packets++;
|
|
tunnel->stat.rx_bytes += skb->len;
|
|
skb->dev = tunnel->dev;
|
|
dst_release(skb->dst);
|
|
skb->dst = NULL;
|
|
nf_reset(skb);
|
|
ipip_ecn_decapsulate(iph, skb);
|
|
netif_rx(skb);
|
|
read_unlock(&ipip_lock);
|
|
return 0;
|
|
}
|
|
read_unlock(&ipip_lock);
|
|
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* This function assumes it is being called from dev_queue_xmit()
|
|
* and that skb is filled properly by that function.
|
|
*/
|
|
|
|
static int ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct net_device_stats *stats = &tunnel->stat;
|
|
struct iphdr *tiph = &tunnel->parms.iph;
|
|
u8 tos = tunnel->parms.iph.tos;
|
|
u16 df = tiph->frag_off;
|
|
struct rtable *rt; /* Route to the other host */
|
|
struct net_device *tdev; /* Device to other host */
|
|
struct iphdr *old_iph = skb->nh.iph;
|
|
struct iphdr *iph; /* Our new IP header */
|
|
int max_headroom; /* The extra header space needed */
|
|
u32 dst = tiph->daddr;
|
|
int mtu;
|
|
|
|
if (tunnel->recursion++) {
|
|
tunnel->stat.collisions++;
|
|
goto tx_error;
|
|
}
|
|
|
|
if (skb->protocol != htons(ETH_P_IP))
|
|
goto tx_error;
|
|
|
|
if (tos&1)
|
|
tos = old_iph->tos;
|
|
|
|
if (!dst) {
|
|
/* NBMA tunnel */
|
|
if ((rt = (struct rtable*)skb->dst) == NULL) {
|
|
tunnel->stat.tx_fifo_errors++;
|
|
goto tx_error;
|
|
}
|
|
if ((dst = rt->rt_gateway) == 0)
|
|
goto tx_error_icmp;
|
|
}
|
|
|
|
{
|
|
struct flowi fl = { .oif = tunnel->parms.link,
|
|
.nl_u = { .ip4_u =
|
|
{ .daddr = dst,
|
|
.saddr = tiph->saddr,
|
|
.tos = RT_TOS(tos) } },
|
|
.proto = IPPROTO_IPIP };
|
|
if (ip_route_output_key(&rt, &fl)) {
|
|
tunnel->stat.tx_carrier_errors++;
|
|
goto tx_error_icmp;
|
|
}
|
|
}
|
|
tdev = rt->u.dst.dev;
|
|
|
|
if (tdev == dev) {
|
|
ip_rt_put(rt);
|
|
tunnel->stat.collisions++;
|
|
goto tx_error;
|
|
}
|
|
|
|
if (tiph->frag_off)
|
|
mtu = dst_mtu(&rt->u.dst) - sizeof(struct iphdr);
|
|
else
|
|
mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
|
|
|
|
if (mtu < 68) {
|
|
tunnel->stat.collisions++;
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
if (skb->dst)
|
|
skb->dst->ops->update_pmtu(skb->dst, mtu);
|
|
|
|
df |= (old_iph->frag_off&htons(IP_DF));
|
|
|
|
if ((old_iph->frag_off&htons(IP_DF)) && mtu < ntohs(old_iph->tot_len)) {
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
|
|
if (tunnel->err_count > 0) {
|
|
if (jiffies - tunnel->err_time < IPTUNNEL_ERR_TIMEO) {
|
|
tunnel->err_count--;
|
|
dst_link_failure(skb);
|
|
} else
|
|
tunnel->err_count = 0;
|
|
}
|
|
|
|
/*
|
|
* Okay, now see if we can stuff it in the buffer as-is.
|
|
*/
|
|
max_headroom = (LL_RESERVED_SPACE(tdev)+sizeof(struct iphdr));
|
|
|
|
if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) {
|
|
struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
|
|
if (!new_skb) {
|
|
ip_rt_put(rt);
|
|
stats->tx_dropped++;
|
|
dev_kfree_skb(skb);
|
|
tunnel->recursion--;
|
|
return 0;
|
|
}
|
|
if (skb->sk)
|
|
skb_set_owner_w(new_skb, skb->sk);
|
|
dev_kfree_skb(skb);
|
|
skb = new_skb;
|
|
old_iph = skb->nh.iph;
|
|
}
|
|
|
|
skb->h.raw = skb->nh.raw;
|
|
skb->nh.raw = skb_push(skb, sizeof(struct iphdr));
|
|
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
|
|
IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
|
|
IPSKB_REROUTED);
|
|
dst_release(skb->dst);
|
|
skb->dst = &rt->u.dst;
|
|
|
|
/*
|
|
* Push down and install the IPIP header.
|
|
*/
|
|
|
|
iph = skb->nh.iph;
|
|
iph->version = 4;
|
|
iph->ihl = sizeof(struct iphdr)>>2;
|
|
iph->frag_off = df;
|
|
iph->protocol = IPPROTO_IPIP;
|
|
iph->tos = INET_ECN_encapsulate(tos, old_iph->tos);
|
|
iph->daddr = rt->rt_dst;
|
|
iph->saddr = rt->rt_src;
|
|
|
|
if ((iph->ttl = tiph->ttl) == 0)
|
|
iph->ttl = old_iph->ttl;
|
|
|
|
nf_reset(skb);
|
|
|
|
IPTUNNEL_XMIT();
|
|
tunnel->recursion--;
|
|
return 0;
|
|
|
|
tx_error_icmp:
|
|
dst_link_failure(skb);
|
|
tx_error:
|
|
stats->tx_errors++;
|
|
dev_kfree_skb(skb);
|
|
tunnel->recursion--;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
ipip_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
|
|
{
|
|
int err = 0;
|
|
struct ip_tunnel_parm p;
|
|
struct ip_tunnel *t;
|
|
|
|
switch (cmd) {
|
|
case SIOCGETTUNNEL:
|
|
t = NULL;
|
|
if (dev == ipip_fb_tunnel_dev) {
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
|
|
err = -EFAULT;
|
|
break;
|
|
}
|
|
t = ipip_tunnel_locate(&p, 0);
|
|
}
|
|
if (t == NULL)
|
|
t = netdev_priv(dev);
|
|
memcpy(&p, &t->parms, sizeof(p));
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
|
|
err = -EFAULT;
|
|
break;
|
|
|
|
case SIOCADDTUNNEL:
|
|
case SIOCCHGTUNNEL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
|
|
err = -EFAULT;
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
goto done;
|
|
|
|
err = -EINVAL;
|
|
if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
|
|
p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
|
|
goto done;
|
|
if (p.iph.ttl)
|
|
p.iph.frag_off |= htons(IP_DF);
|
|
|
|
t = ipip_tunnel_locate(&p, cmd == SIOCADDTUNNEL);
|
|
|
|
if (dev != ipip_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
|
|
if (t != NULL) {
|
|
if (t->dev != dev) {
|
|
err = -EEXIST;
|
|
break;
|
|
}
|
|
} else {
|
|
if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
|
|
(!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
t = netdev_priv(dev);
|
|
ipip_tunnel_unlink(t);
|
|
t->parms.iph.saddr = p.iph.saddr;
|
|
t->parms.iph.daddr = p.iph.daddr;
|
|
memcpy(dev->dev_addr, &p.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &p.iph.daddr, 4);
|
|
ipip_tunnel_link(t);
|
|
netdev_state_change(dev);
|
|
}
|
|
}
|
|
|
|
if (t) {
|
|
err = 0;
|
|
if (cmd == SIOCCHGTUNNEL) {
|
|
t->parms.iph.ttl = p.iph.ttl;
|
|
t->parms.iph.tos = p.iph.tos;
|
|
t->parms.iph.frag_off = p.iph.frag_off;
|
|
}
|
|
if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
|
|
err = -EFAULT;
|
|
} else
|
|
err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
|
|
break;
|
|
|
|
case SIOCDELTUNNEL:
|
|
err = -EPERM;
|
|
if (!capable(CAP_NET_ADMIN))
|
|
goto done;
|
|
|
|
if (dev == ipip_fb_tunnel_dev) {
|
|
err = -EFAULT;
|
|
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
|
|
goto done;
|
|
err = -ENOENT;
|
|
if ((t = ipip_tunnel_locate(&p, 0)) == NULL)
|
|
goto done;
|
|
err = -EPERM;
|
|
if (t->dev == ipip_fb_tunnel_dev)
|
|
goto done;
|
|
dev = t->dev;
|
|
}
|
|
err = unregister_netdevice(dev);
|
|
break;
|
|
|
|
default:
|
|
err = -EINVAL;
|
|
}
|
|
|
|
done:
|
|
return err;
|
|
}
|
|
|
|
static struct net_device_stats *ipip_tunnel_get_stats(struct net_device *dev)
|
|
{
|
|
return &(((struct ip_tunnel*)netdev_priv(dev))->stat);
|
|
}
|
|
|
|
static int ipip_tunnel_change_mtu(struct net_device *dev, int new_mtu)
|
|
{
|
|
if (new_mtu < 68 || new_mtu > 0xFFF8 - sizeof(struct iphdr))
|
|
return -EINVAL;
|
|
dev->mtu = new_mtu;
|
|
return 0;
|
|
}
|
|
|
|
static void ipip_tunnel_setup(struct net_device *dev)
|
|
{
|
|
SET_MODULE_OWNER(dev);
|
|
dev->uninit = ipip_tunnel_uninit;
|
|
dev->hard_start_xmit = ipip_tunnel_xmit;
|
|
dev->get_stats = ipip_tunnel_get_stats;
|
|
dev->do_ioctl = ipip_tunnel_ioctl;
|
|
dev->change_mtu = ipip_tunnel_change_mtu;
|
|
dev->destructor = free_netdev;
|
|
|
|
dev->type = ARPHRD_TUNNEL;
|
|
dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr);
|
|
dev->mtu = ETH_DATA_LEN - sizeof(struct iphdr);
|
|
dev->flags = IFF_NOARP;
|
|
dev->iflink = 0;
|
|
dev->addr_len = 4;
|
|
}
|
|
|
|
static int ipip_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct net_device *tdev = NULL;
|
|
struct ip_tunnel *tunnel;
|
|
struct iphdr *iph;
|
|
|
|
tunnel = netdev_priv(dev);
|
|
iph = &tunnel->parms.iph;
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
|
|
memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
|
|
|
|
if (iph->daddr) {
|
|
struct flowi fl = { .oif = tunnel->parms.link,
|
|
.nl_u = { .ip4_u =
|
|
{ .daddr = iph->daddr,
|
|
.saddr = iph->saddr,
|
|
.tos = RT_TOS(iph->tos) } },
|
|
.proto = IPPROTO_IPIP };
|
|
struct rtable *rt;
|
|
if (!ip_route_output_key(&rt, &fl)) {
|
|
tdev = rt->u.dst.dev;
|
|
ip_rt_put(rt);
|
|
}
|
|
dev->flags |= IFF_POINTOPOINT;
|
|
}
|
|
|
|
if (!tdev && tunnel->parms.link)
|
|
tdev = __dev_get_by_index(tunnel->parms.link);
|
|
|
|
if (tdev) {
|
|
dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
|
|
dev->mtu = tdev->mtu - sizeof(struct iphdr);
|
|
}
|
|
dev->iflink = tunnel->parms.link;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init ipip_fb_tunnel_init(struct net_device *dev)
|
|
{
|
|
struct ip_tunnel *tunnel = netdev_priv(dev);
|
|
struct iphdr *iph = &tunnel->parms.iph;
|
|
|
|
tunnel->dev = dev;
|
|
strcpy(tunnel->parms.name, dev->name);
|
|
|
|
iph->version = 4;
|
|
iph->protocol = IPPROTO_IPIP;
|
|
iph->ihl = 5;
|
|
|
|
dev_hold(dev);
|
|
tunnels_wc[0] = tunnel;
|
|
return 0;
|
|
}
|
|
|
|
static struct xfrm_tunnel ipip_handler = {
|
|
.handler = ipip_rcv,
|
|
.err_handler = ipip_err,
|
|
.priority = 1,
|
|
};
|
|
|
|
static char banner[] __initdata =
|
|
KERN_INFO "IPv4 over IPv4 tunneling driver\n";
|
|
|
|
static int __init ipip_init(void)
|
|
{
|
|
int err;
|
|
|
|
printk(banner);
|
|
|
|
if (xfrm4_tunnel_register(&ipip_handler)) {
|
|
printk(KERN_INFO "ipip init: can't register tunnel\n");
|
|
return -EAGAIN;
|
|
}
|
|
|
|
ipip_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel),
|
|
"tunl0",
|
|
ipip_tunnel_setup);
|
|
if (!ipip_fb_tunnel_dev) {
|
|
err = -ENOMEM;
|
|
goto err1;
|
|
}
|
|
|
|
ipip_fb_tunnel_dev->init = ipip_fb_tunnel_init;
|
|
|
|
if ((err = register_netdev(ipip_fb_tunnel_dev)))
|
|
goto err2;
|
|
out:
|
|
return err;
|
|
err2:
|
|
free_netdev(ipip_fb_tunnel_dev);
|
|
err1:
|
|
xfrm4_tunnel_deregister(&ipip_handler);
|
|
goto out;
|
|
}
|
|
|
|
static void __exit ipip_destroy_tunnels(void)
|
|
{
|
|
int prio;
|
|
|
|
for (prio = 1; prio < 4; prio++) {
|
|
int h;
|
|
for (h = 0; h < HASH_SIZE; h++) {
|
|
struct ip_tunnel *t;
|
|
while ((t = tunnels[prio][h]) != NULL)
|
|
unregister_netdevice(t->dev);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void __exit ipip_fini(void)
|
|
{
|
|
if (xfrm4_tunnel_deregister(&ipip_handler))
|
|
printk(KERN_INFO "ipip close: can't deregister tunnel\n");
|
|
|
|
rtnl_lock();
|
|
ipip_destroy_tunnels();
|
|
unregister_netdevice(ipip_fb_tunnel_dev);
|
|
rtnl_unlock();
|
|
}
|
|
|
|
module_init(ipip_init);
|
|
module_exit(ipip_fini);
|
|
MODULE_LICENSE("GPL");
|