summaryrefslogtreecommitdiff
path: root/net/ipv4/ipip.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv4/ipip.c')
-rw-r--r--net/ipv4/ipip.c905
1 files changed, 905 insertions, 0 deletions
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
new file mode 100644
index 00000000000..68a78731f72
--- /dev/null
+++ b/net/ipv4/ipip.c
@@ -0,0 +1,905 @@
+/*
+ * Linux NET3: IP/IP protocol decoder.
+ *
+ * Version: $Id: ipip.c,v 1.50 2001/10/02 02:22:36 davem Exp $
+ *
+ * Authors:
+ * Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
+ *
+ * Fixes:
+ * Alan Cox : Merged and made usable non modular (its so tiny its silly as
+ * a module taking up 2 pages).
+ * Alan Cox : Fixed bug with 1.3.18 and IPIP not working (now needs to set skb->h.iph)
+ * to keep ip_forward happy.
+ * Alan Cox : More fixes for 1.3.21, and firewall fix. Maybe this will work soon 8).
+ * Kai Schulte : Fixed #defines for IP_FIREWALL->FIREWALL
+ * David Woodhouse : Perform some basic ICMP handling.
+ * IPIP Routing without decapsulation.
+ * Carlos Picoto : GRE over IP support
+ * Alexey Kuznetsov: Reworked. Really, now it is truncated version of ipv4/ip_gre.c.
+ * I do not want to merge them together.
+ *
+ * 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.
+ *
+ */
+
+/* tunnel.c: an IP tunnel driver
+
+ The purpose of this driver is to provide an IP tunnel through
+ which you can tunnel network traffic transparently across subnets.
+
+ This was written by looking at Nick Holloway's dummy driver
+ Thanks for the great code!
+
+ -Sam Lantinga (slouken@cs.ucdavis.edu) 02/01/95
+
+ Minor tweaks:
+ Cleaned up the code a little and added some pre-1.3.0 tweaks.
+ dev->hard_header/hard_header_len changed to use no headers.
+ Comments/bracketing tweaked.
+ Made the tunnels use dev->name not tunnel: when error reporting.
+ Added tx_dropped stat
+
+ -Alan Cox (Alan.Cox@linux.org) 21 March 95
+
+ Reworked:
+ Changed to tunnel to destination gateway in addition to the
+ tunnel's pointopoint address
+ Almost completely rewritten
+ Note: There is currently no firewall or ICMP handling done.
+
+ -Sam Lantinga (slouken@cs.ucdavis.edu) 02/13/96
+
+*/
+
+/* Things I wish I had known when writing the tunnel driver:
+
+ When the tunnel_xmit() function is called, the skb contains the
+ packet to be sent (plus a great deal of extra info), and dev
+ contains the tunnel device that _we_ are.
+
+ When we are passed a packet, we are expected to fill in the
+ source address with our source IP address.
+
+ What is the proper way to allocate, copy and free a buffer?
+ After you allocate it, it is a "0 length" chunk of memory
+ starting at zero. If you want to add headers to the buffer
+ later, you'll have to call "skb_reserve(skb, amount)" with
+ the amount of memory you want reserved. Then, you call
+ "skb_put(skb, amount)" with the amount of space you want in
+ the buffer. skb_put() returns a pointer to the top (#0) of
+ that buffer. skb->len is set to the amount of space you have
+ "allocated" with skb_put(). You can then write up to skb->len
+ bytes to that buffer. If you need more, you can call skb_put()
+ again with the additional amount of space you need. You can
+ find out how much more space you can allocate by calling
+ "skb_tailroom(skb)".
+ Now, to add header space, call "skb_push(skb, header_len)".
+ This creates space at the beginning of the buffer and returns
+ a pointer to this new space. If later you need to strip a
+ header from a buffer, call "skb_pull(skb, header_len)".
+ skb_headroom() will return how much space is left at the top
+ of the buffer (before the main data). Remember, this headroom
+ space must be reserved before the skb_put() function is called.
+ */
+
+/*
+ This version of net/ipv4/ipip.c is cloned of net/ipv4/ip_gre.c
+
+ For comments look at net/ipv4/ip_gre.c --ANK
+ */
+
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <asm/uaccess.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/in.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/if_arp.h>
+#include <linux/mroute.h>
+#include <linux/init.h>
+#include <linux/netfilter_ipv4.h>
+
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <net/ipip.h>
+#include <net/inet_ecn.h>
+#include <net/xfrm.h>
+
+#define HASH_SIZE 16
+#define HASH(addr) ((addr^(addr>>4))&0xF)
+
+static int ipip_fb_tunnel_init(struct net_device *dev);
+static int ipip_tunnel_init(struct net_device *dev);
+static void ipip_tunnel_setup(struct net_device *dev);
+
+static struct net_device *ipip_fb_tunnel_dev;
+
+static struct ip_tunnel *tunnels_r_l[HASH_SIZE];
+static struct ip_tunnel *tunnels_r[HASH_SIZE];
+static struct ip_tunnel *tunnels_l[HASH_SIZE];
+static struct ip_tunnel *tunnels_wc[1];
+static struct ip_tunnel **tunnels[4] = { tunnels_wc, tunnels_l, tunnels_r, tunnels_r_l };
+
+static DEFINE_RWLOCK(ipip_lock);
+
+static struct ip_tunnel * ipip_tunnel_lookup(u32 remote, u32 local)
+{
+ unsigned h0 = HASH(remote);
+ unsigned h1 = HASH(local);
+ struct ip_tunnel *t;
+
+ for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
+ if (local == t->parms.iph.saddr &&
+ remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
+ return t;
+ }
+ for (t = tunnels_r[h0]; t; t = t->next) {
+ if (remote == t->parms.iph.daddr && (t->dev->flags&IFF_UP))
+ return t;
+ }
+ for (t = tunnels_l[h1]; t; t = t->next) {
+ if (local == t->parms.iph.saddr && (t->dev->flags&IFF_UP))
+ return t;
+ }
+ if ((t = tunnels_wc[0]) != NULL && (t->dev->flags&IFF_UP))
+ return t;
+ return NULL;
+}
+
+static struct ip_tunnel **ipip_bucket(struct ip_tunnel *t)
+{
+ u32 remote = t->parms.iph.daddr;
+ u32 local = t->parms.iph.saddr;
+ unsigned h = 0;
+ int prio = 0;
+
+ if (remote) {
+ prio |= 2;
+ h ^= HASH(remote);
+ }
+ if (local) {
+ prio |= 1;
+ h ^= HASH(local);
+ }
+ return &tunnels[prio][h];
+}
+
+
+static void ipip_tunnel_unlink(struct ip_tunnel *t)
+{
+ struct ip_tunnel **tp;
+
+ for (tp = ipip_bucket(t); *tp; tp = &(*tp)->next) {
+ if (t == *tp) {
+ write_lock_bh(&ipip_lock);
+ *tp = t->next;
+ write_unlock_bh(&ipip_lock);
+ break;
+ }
+ }
+}
+
+static void ipip_tunnel_link(struct ip_tunnel *t)
+{
+ struct ip_tunnel **tp = ipip_bucket(t);
+
+ t->next = *tp;
+ write_lock_bh(&ipip_lock);
+ *tp = t;
+ write_unlock_bh(&ipip_lock);
+}
+
+static struct ip_tunnel * ipip_tunnel_locate(struct ip_tunnel_parm *parms, int create)
+{
+ u32 remote = parms->iph.daddr;
+ u32 local = parms->iph.saddr;
+ struct ip_tunnel *t, **tp, *nt;
+ struct net_device *dev;
+ unsigned h = 0;
+ int prio = 0;
+ char name[IFNAMSIZ];
+
+ if (remote) {
+ prio |= 2;
+ h ^= HASH(remote);
+ }
+ if (local) {
+ prio |= 1;
+ h ^= HASH(local);
+ }
+ for (tp = &tunnels[prio][h]; (t = *tp) != NULL; tp = &t->next) {
+ if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr)
+ return t;
+ }
+ if (!create)
+ return NULL;
+
+ if (parms->name[0])
+ strlcpy(name, parms->name, IFNAMSIZ);
+ else {
+ int i;
+ for (i=1; i<100; i++) {
+ sprintf(name, "tunl%d", i);
+ if (__dev_get_by_name(name) == NULL)
+ break;
+ }
+ if (i==100)
+ goto failed;
+ }
+
+ dev = alloc_netdev(sizeof(*t), name, ipip_tunnel_setup);
+ if (dev == NULL)
+ return NULL;
+
+ nt = dev->priv;
+ SET_MODULE_OWNER(dev);
+ dev->init = ipip_tunnel_init;
+ nt->parms = *parms;
+
+ if (register_netdevice(dev) < 0) {
+ free_netdev(dev);
+ goto failed;
+ }
+
+ dev_hold(dev);
+ ipip_tunnel_link(nt);
+ /* Do not decrement MOD_USE_COUNT here. */
+ return nt;
+
+failed:
+ return NULL;
+}
+
+static void ipip_tunnel_uninit(struct net_device *dev)
+{
+ if (dev == ipip_fb_tunnel_dev) {
+ write_lock_bh(&ipip_lock);
+ tunnels_wc[0] = NULL;
+ write_unlock_bh(&ipip_lock);
+ } else
+ ipip_tunnel_unlink((struct ip_tunnel*)dev->priv);
+ dev_put(dev);
+}
+
+static void ipip_err(struct sk_buff *skb, void *__unused)
+{
+#ifndef I_WISH_WORLD_WERE_PERFECT
+
+/* It is not :-( All the routers (except for Linux) return only
+ 8 bytes of packet payload. It means, that precise relaying of
+ ICMP in the real Internet is absolutely infeasible.
+ */
+ struct iphdr *iph = (struct iphdr*)skb->data;
+ int type = skb->h.icmph->type;
+ int code = skb->h.icmph->code;
+ struct ip_tunnel *t;
+
+ switch (type) {
+ default:
+ case ICMP_PARAMETERPROB:
+ return;
+
+ case ICMP_DEST_UNREACH:
+ switch (code) {
+ case ICMP_SR_FAILED:
+ case ICMP_PORT_UNREACH:
+ /* Impossible event. */
+ return;
+ case ICMP_FRAG_NEEDED:
+ /* Soft state for pmtu is maintained by IP core. */
+ return;
+ default:
+ /* All others are translated to HOST_UNREACH.
+ rfc2003 contains "deep thoughts" about NET_UNREACH,
+ I believe they are just ether pollution. --ANK
+ */
+ break;
+ }
+ break;
+ case ICMP_TIME_EXCEEDED:
+ if (code != ICMP_EXC_TTL)
+ return;
+ break;
+ }
+
+ read_lock(&ipip_lock);
+ t = ipip_tunnel_lookup(iph->daddr, iph->saddr);
+ if (t == NULL || t->parms.iph.daddr == 0)
+ goto out;
+ if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
+ goto out;
+
+ if (jiffies - t->err_time < IPTUNNEL_ERR_TIMEO)
+ t->err_count++;
+ else
+ t->err_count = 1;
+ t->err_time = jiffies;
+out:
+ read_unlock(&ipip_lock);
+ return;
+#else
+ struct iphdr *iph = (struct iphdr*)dp;
+ int hlen = iph->ihl<<2;
+ struct iphdr *eiph;
+ int type = skb->h.icmph->type;
+ int code = skb->h.icmph->code;
+ int rel_type = 0;
+ int rel_code = 0;
+ int rel_info = 0;
+ struct sk_buff *skb2;
+ struct flowi fl;
+ struct rtable *rt;
+
+ if (len < hlen + sizeof(struct iphdr))
+ return;
+ eiph = (struct iphdr*)(dp + hlen);
+
+ switch (type) {
+ default:
+ return;
+ case ICMP_PARAMETERPROB:
+ if (skb->h.icmph->un.gateway < hlen)
+ return;
+
+ /* So... This guy found something strange INSIDE encapsulated
+ packet. Well, he is fool, but what can we do ?
+ */
+ rel_type = ICMP_PARAMETERPROB;
+ rel_info = skb->h.icmph->un.gateway - hlen;
+ break;
+
+ case ICMP_DEST_UNREACH:
+ switch (code) {
+ case ICMP_SR_FAILED:
+ case ICMP_PORT_UNREACH:
+ /* Impossible event. */
+ return;
+ case ICMP_FRAG_NEEDED:
+ /* And it is the only really necessary thing :-) */
+ rel_info = ntohs(skb->h.icmph->un.frag.mtu);
+ if (rel_info < hlen+68)
+ return;
+ rel_info -= hlen;
+ /* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */
+ if (rel_info > ntohs(eiph->tot_len))
+ return;
+ break;
+ default:
+ /* All others are translated to HOST_UNREACH.
+ rfc2003 contains "deep thoughts" about NET_UNREACH,
+ I believe, it is just ether pollution. --ANK
+ */
+ rel_type = ICMP_DEST_UNREACH;
+ rel_code = ICMP_HOST_UNREACH;
+ break;
+ }
+ break;
+ case ICMP_TIME_EXCEEDED:
+ if (code != ICMP_EXC_TTL)
+ return;
+ break;
+ }
+
+ /* Prepare fake skb to feed it to icmp_send */
+ skb2 = skb_clone(skb, GFP_ATOMIC);
+ if (skb2 == NULL)
+ return;
+ dst_release(skb2->dst);
+ skb2->dst = NULL;
+ skb_pull(skb2, skb->data - (u8*)eiph);
+ skb2->nh.raw = skb2->data;
+
+ /* Try to guess incoming interface */
+ memset(&fl, 0, sizeof(fl));
+ fl.fl4_daddr = eiph->saddr;
+ fl.fl4_tos = RT_TOS(eiph->tos);
+ fl.proto = IPPROTO_IPIP;
+ if (ip_route_output_key(&rt, &key)) {
+ kfree_skb(skb2);
+ return;
+ }
+ skb2->dev = rt->u.dst.dev;
+
+ /* route "incoming" packet */
+ if (rt->rt_flags&RTCF_LOCAL) {
+ ip_rt_put(rt);
+ rt = NULL;
+ fl.fl4_daddr = eiph->daddr;
+ fl.fl4_src = eiph->saddr;
+ fl.fl4_tos = eiph->tos;
+ if (ip_route_output_key(&rt, &fl) ||
+ rt->u.dst.dev->type != ARPHRD_TUNNEL) {
+ ip_rt_put(rt);
+ kfree_skb(skb2);
+ return;
+ }
+ } else {
+ ip_rt_put(rt);
+ if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) ||
+ skb2->dst->dev->type != ARPHRD_TUNNEL) {
+ kfree_skb(skb2);
+ return;
+ }
+ }
+
+ /* change mtu on this route */
+ if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
+ if (rel_info > dst_mtu(skb2->dst)) {
+ kfree_skb(skb2);
+ return;
+ }
+ skb2->dst->ops->update_pmtu(skb2->dst, rel_info);
+ rel_info = htonl(rel_info);
+ } else if (type == ICMP_TIME_EXCEEDED) {
+ struct ip_tunnel *t = (struct ip_tunnel*)skb2->dev->priv;
+ if (t->parms.iph.ttl) {
+ rel_type = ICMP_DEST_UNREACH;
+ rel_code = ICMP_HOST_UNREACH;
+ }
+ }
+
+ icmp_send(skb2, rel_type, rel_code, rel_info);
+ kfree_skb(skb2);
+ return;
+#endif
+}
+
+static inline void ipip_ecn_decapsulate(struct iphdr *outer_iph, struct sk_buff *skb)
+{
+ struct iphdr *inner_iph = skb->nh.iph;
+
+ if (INET_ECN_is_ce(outer_iph->tos))
+ IP_ECN_set_ce(inner_iph);
+}
+
+static int ipip_rcv(struct sk_buff *skb)
+{
+ struct iphdr *iph;
+ struct ip_tunnel *tunnel;
+
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ goto out;
+
+ iph = skb->nh.iph;
+
+ read_lock(&ipip_lock);
+ if ((tunnel = ipip_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
+ if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
+ read_unlock(&ipip_lock);
+ kfree_skb(skb);
+ return 0;
+ }
+
+ secpath_reset(skb);
+
+ skb->mac.raw = skb->nh.raw;
+ skb->nh.raw = skb->data;
+ memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+ skb->protocol = htons(ETH_P_IP);
+ skb->pkt_type = PACKET_HOST;
+
+ 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);
+
+out:
+ 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 = (struct ip_tunnel*)dev->priv;
+ 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));
+ 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 = (struct ip_tunnel*)dev->priv;
+ 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 = (struct ip_tunnel*)dev->priv;
+ 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*)dev->priv)->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 = 1500 - 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 = (struct ip_tunnel*)dev->priv;
+ 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 = dev->priv;
+ 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,
+};
+
+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) < 0) {
+ 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_fini(void)
+{
+ if (xfrm4_tunnel_deregister(&ipip_handler) < 0)
+ printk(KERN_INFO "ipip close: can't deregister tunnel\n");
+
+ unregister_netdev(ipip_fb_tunnel_dev);
+}
+
+module_init(ipip_init);
+module_exit(ipip_fini);
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-20 11:27:58 +0000