| /* |
| * 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"); |