| /* |
| * IPv6 over IPv6 tunnel device |
| * Linux INET6 implementation |
| * |
| * Authors: |
| * Ville Nuorvala <vnuorval@tcs.hut.fi> |
| * |
| * $Id$ |
| * |
| * Based on: |
| * linux/net/ipv6/sit.c |
| * |
| * RFC 2473 |
| * |
| * 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. |
| * |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/capability.h> |
| #include <linux/errno.h> |
| #include <linux/types.h> |
| #include <linux/sockios.h> |
| #include <linux/if.h> |
| #include <linux/in.h> |
| #include <linux/ip.h> |
| #include <linux/if_tunnel.h> |
| #include <linux/net.h> |
| #include <linux/in6.h> |
| #include <linux/netdevice.h> |
| #include <linux/if_arp.h> |
| #include <linux/icmpv6.h> |
| #include <linux/init.h> |
| #include <linux/route.h> |
| #include <linux/rtnetlink.h> |
| #include <linux/netfilter_ipv6.h> |
| |
| #include <asm/uaccess.h> |
| #include <asm/atomic.h> |
| |
| #include <net/ip.h> |
| #include <net/ipv6.h> |
| #include <net/ip6_route.h> |
| #include <net/addrconf.h> |
| #include <net/ip6_tunnel.h> |
| #include <net/xfrm.h> |
| #include <net/dsfield.h> |
| #include <net/inet_ecn.h> |
| |
| MODULE_AUTHOR("Ville Nuorvala"); |
| MODULE_DESCRIPTION("IPv6-in-IPv6 tunnel"); |
| MODULE_LICENSE("GPL"); |
| |
| #define IPV6_TLV_TEL_DST_SIZE 8 |
| |
| #ifdef IP6_TNL_DEBUG |
| #define IP6_TNL_TRACE(x...) printk(KERN_DEBUG "%s:" x "\n", __FUNCTION__) |
| #else |
| #define IP6_TNL_TRACE(x...) do {;} while(0) |
| #endif |
| |
| #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) |
| |
| #define HASH_SIZE 32 |
| |
| #define HASH(addr) (((addr)->s6_addr32[0] ^ (addr)->s6_addr32[1] ^ \ |
| (addr)->s6_addr32[2] ^ (addr)->s6_addr32[3]) & \ |
| (HASH_SIZE - 1)) |
| |
| static int ip6ip6_fb_tnl_dev_init(struct net_device *dev); |
| static int ip6ip6_tnl_dev_init(struct net_device *dev); |
| static void ip6ip6_tnl_dev_setup(struct net_device *dev); |
| |
| /* the IPv6 tunnel fallback device */ |
| static struct net_device *ip6ip6_fb_tnl_dev; |
| |
| |
| /* lists for storing tunnels in use */ |
| static struct ip6_tnl *tnls_r_l[HASH_SIZE]; |
| static struct ip6_tnl *tnls_wc[1]; |
| static struct ip6_tnl **tnls[2] = { tnls_wc, tnls_r_l }; |
| |
| /* lock for the tunnel lists */ |
| static DEFINE_RWLOCK(ip6ip6_lock); |
| |
| static inline struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t) |
| { |
| struct dst_entry *dst = t->dst_cache; |
| |
| if (dst && dst->obsolete && |
| dst->ops->check(dst, t->dst_cookie) == NULL) { |
| t->dst_cache = NULL; |
| dst_release(dst); |
| return NULL; |
| } |
| |
| return dst; |
| } |
| |
| static inline void ip6_tnl_dst_reset(struct ip6_tnl *t) |
| { |
| dst_release(t->dst_cache); |
| t->dst_cache = NULL; |
| } |
| |
| static inline void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst) |
| { |
| struct rt6_info *rt = (struct rt6_info *) dst; |
| t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; |
| dst_release(t->dst_cache); |
| t->dst_cache = dst; |
| } |
| |
| /** |
| * ip6ip6_tnl_lookup - fetch tunnel matching the end-point addresses |
| * @remote: the address of the tunnel exit-point |
| * @local: the address of the tunnel entry-point |
| * |
| * Return: |
| * tunnel matching given end-points if found, |
| * else fallback tunnel if its device is up, |
| * else %NULL |
| **/ |
| |
| static struct ip6_tnl * |
| ip6ip6_tnl_lookup(struct in6_addr *remote, struct in6_addr *local) |
| { |
| unsigned h0 = HASH(remote); |
| unsigned h1 = HASH(local); |
| struct ip6_tnl *t; |
| |
| for (t = tnls_r_l[h0 ^ h1]; t; t = t->next) { |
| if (ipv6_addr_equal(local, &t->parms.laddr) && |
| ipv6_addr_equal(remote, &t->parms.raddr) && |
| (t->dev->flags & IFF_UP)) |
| return t; |
| } |
| if ((t = tnls_wc[0]) != NULL && (t->dev->flags & IFF_UP)) |
| return t; |
| |
| return NULL; |
| } |
| |
| /** |
| * ip6ip6_bucket - get head of list matching given tunnel parameters |
| * @p: parameters containing tunnel end-points |
| * |
| * Description: |
| * ip6ip6_bucket() returns the head of the list matching the |
| * &struct in6_addr entries laddr and raddr in @p. |
| * |
| * Return: head of IPv6 tunnel list |
| **/ |
| |
| static struct ip6_tnl ** |
| ip6ip6_bucket(struct ip6_tnl_parm *p) |
| { |
| struct in6_addr *remote = &p->raddr; |
| struct in6_addr *local = &p->laddr; |
| unsigned h = 0; |
| int prio = 0; |
| |
| if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { |
| prio = 1; |
| h = HASH(remote) ^ HASH(local); |
| } |
| return &tnls[prio][h]; |
| } |
| |
| /** |
| * ip6ip6_tnl_link - add tunnel to hash table |
| * @t: tunnel to be added |
| **/ |
| |
| static void |
| ip6ip6_tnl_link(struct ip6_tnl *t) |
| { |
| struct ip6_tnl **tp = ip6ip6_bucket(&t->parms); |
| |
| t->next = *tp; |
| write_lock_bh(&ip6ip6_lock); |
| *tp = t; |
| write_unlock_bh(&ip6ip6_lock); |
| } |
| |
| /** |
| * ip6ip6_tnl_unlink - remove tunnel from hash table |
| * @t: tunnel to be removed |
| **/ |
| |
| static void |
| ip6ip6_tnl_unlink(struct ip6_tnl *t) |
| { |
| struct ip6_tnl **tp; |
| |
| for (tp = ip6ip6_bucket(&t->parms); *tp; tp = &(*tp)->next) { |
| if (t == *tp) { |
| write_lock_bh(&ip6ip6_lock); |
| *tp = t->next; |
| write_unlock_bh(&ip6ip6_lock); |
| break; |
| } |
| } |
| } |
| |
| /** |
| * ip6_tnl_create() - create a new tunnel |
| * @p: tunnel parameters |
| * @pt: pointer to new tunnel |
| * |
| * Description: |
| * Create tunnel matching given parameters. |
| * |
| * Return: |
| * 0 on success |
| **/ |
| |
| static int |
| ip6_tnl_create(struct ip6_tnl_parm *p, struct ip6_tnl **pt) |
| { |
| struct net_device *dev; |
| struct ip6_tnl *t; |
| char name[IFNAMSIZ]; |
| int err; |
| |
| if (p->name[0]) { |
| strlcpy(name, p->name, IFNAMSIZ); |
| } else { |
| int i; |
| for (i = 1; i < IP6_TNL_MAX; i++) { |
| sprintf(name, "ip6tnl%d", i); |
| if (__dev_get_by_name(name) == NULL) |
| break; |
| } |
| if (i == IP6_TNL_MAX) |
| return -ENOBUFS; |
| } |
| dev = alloc_netdev(sizeof (*t), name, ip6ip6_tnl_dev_setup); |
| if (dev == NULL) |
| return -ENOMEM; |
| |
| t = netdev_priv(dev); |
| dev->init = ip6ip6_tnl_dev_init; |
| t->parms = *p; |
| |
| if ((err = register_netdevice(dev)) < 0) { |
| free_netdev(dev); |
| return err; |
| } |
| dev_hold(dev); |
| |
| ip6ip6_tnl_link(t); |
| *pt = t; |
| return 0; |
| } |
| |
| /** |
| * ip6ip6_tnl_locate - find or create tunnel matching given parameters |
| * @p: tunnel parameters |
| * @create: != 0 if allowed to create new tunnel if no match found |
| * |
| * Description: |
| * ip6ip6_tnl_locate() first tries to locate an existing tunnel |
| * based on @parms. If this is unsuccessful, but @create is set a new |
| * tunnel device is created and registered for use. |
| * |
| * Return: |
| * 0 if tunnel located or created, |
| * -EINVAL if parameters incorrect, |
| * -ENODEV if no matching tunnel available |
| **/ |
| |
| static int |
| ip6ip6_tnl_locate(struct ip6_tnl_parm *p, struct ip6_tnl **pt, int create) |
| { |
| struct in6_addr *remote = &p->raddr; |
| struct in6_addr *local = &p->laddr; |
| struct ip6_tnl *t; |
| |
| if (p->proto != IPPROTO_IPV6) |
| return -EINVAL; |
| |
| for (t = *ip6ip6_bucket(p); t; t = t->next) { |
| if (ipv6_addr_equal(local, &t->parms.laddr) && |
| ipv6_addr_equal(remote, &t->parms.raddr)) { |
| *pt = t; |
| return (create ? -EEXIST : 0); |
| } |
| } |
| if (!create) |
| return -ENODEV; |
| |
| return ip6_tnl_create(p, pt); |
| } |
| |
| /** |
| * ip6ip6_tnl_dev_uninit - tunnel device uninitializer |
| * @dev: the device to be destroyed |
| * |
| * Description: |
| * ip6ip6_tnl_dev_uninit() removes tunnel from its list |
| **/ |
| |
| static void |
| ip6ip6_tnl_dev_uninit(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| |
| if (dev == ip6ip6_fb_tnl_dev) { |
| write_lock_bh(&ip6ip6_lock); |
| tnls_wc[0] = NULL; |
| write_unlock_bh(&ip6ip6_lock); |
| } else { |
| ip6ip6_tnl_unlink(t); |
| } |
| ip6_tnl_dst_reset(t); |
| dev_put(dev); |
| } |
| |
| /** |
| * parse_tvl_tnl_enc_lim - handle encapsulation limit option |
| * @skb: received socket buffer |
| * |
| * Return: |
| * 0 if none was found, |
| * else index to encapsulation limit |
| **/ |
| |
| static __u16 |
| parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw) |
| { |
| struct ipv6hdr *ipv6h = (struct ipv6hdr *) raw; |
| __u8 nexthdr = ipv6h->nexthdr; |
| __u16 off = sizeof (*ipv6h); |
| |
| while (ipv6_ext_hdr(nexthdr) && nexthdr != NEXTHDR_NONE) { |
| __u16 optlen = 0; |
| struct ipv6_opt_hdr *hdr; |
| if (raw + off + sizeof (*hdr) > skb->data && |
| !pskb_may_pull(skb, raw - skb->data + off + sizeof (*hdr))) |
| break; |
| |
| hdr = (struct ipv6_opt_hdr *) (raw + off); |
| if (nexthdr == NEXTHDR_FRAGMENT) { |
| struct frag_hdr *frag_hdr = (struct frag_hdr *) hdr; |
| if (frag_hdr->frag_off) |
| break; |
| optlen = 8; |
| } else if (nexthdr == NEXTHDR_AUTH) { |
| optlen = (hdr->hdrlen + 2) << 2; |
| } else { |
| optlen = ipv6_optlen(hdr); |
| } |
| if (nexthdr == NEXTHDR_DEST) { |
| __u16 i = off + 2; |
| while (1) { |
| struct ipv6_tlv_tnl_enc_lim *tel; |
| |
| /* No more room for encapsulation limit */ |
| if (i + sizeof (*tel) > off + optlen) |
| break; |
| |
| tel = (struct ipv6_tlv_tnl_enc_lim *) &raw[i]; |
| /* return index of option if found and valid */ |
| if (tel->type == IPV6_TLV_TNL_ENCAP_LIMIT && |
| tel->length == 1) |
| return i; |
| /* else jump to next option */ |
| if (tel->type) |
| i += tel->length + 2; |
| else |
| i++; |
| } |
| } |
| nexthdr = hdr->nexthdr; |
| off += optlen; |
| } |
| return 0; |
| } |
| |
| /** |
| * ip6ip6_err - tunnel error handler |
| * |
| * Description: |
| * ip6ip6_err() should handle errors in the tunnel according |
| * to the specifications in RFC 2473. |
| **/ |
| |
| static int |
| ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| int type, int code, int offset, __be32 info) |
| { |
| struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data; |
| struct ip6_tnl *t; |
| int rel_msg = 0; |
| int rel_type = ICMPV6_DEST_UNREACH; |
| int rel_code = ICMPV6_ADDR_UNREACH; |
| __u32 rel_info = 0; |
| __u16 len; |
| int err = -ENOENT; |
| |
| /* If the packet doesn't contain the original IPv6 header we are |
| in trouble since we might need the source address for further |
| processing of the error. */ |
| |
| read_lock(&ip6ip6_lock); |
| if ((t = ip6ip6_tnl_lookup(&ipv6h->daddr, &ipv6h->saddr)) == NULL) |
| goto out; |
| |
| err = 0; |
| |
| switch (type) { |
| __u32 teli; |
| struct ipv6_tlv_tnl_enc_lim *tel; |
| __u32 mtu; |
| case ICMPV6_DEST_UNREACH: |
| if (net_ratelimit()) |
| printk(KERN_WARNING |
| "%s: Path to destination invalid " |
| "or inactive!\n", t->parms.name); |
| rel_msg = 1; |
| break; |
| case ICMPV6_TIME_EXCEED: |
| if (code == ICMPV6_EXC_HOPLIMIT) { |
| if (net_ratelimit()) |
| printk(KERN_WARNING |
| "%s: Too small hop limit or " |
| "routing loop in tunnel!\n", |
| t->parms.name); |
| rel_msg = 1; |
| } |
| break; |
| case ICMPV6_PARAMPROB: |
| /* ignore if parameter problem not caused by a tunnel |
| encapsulation limit sub-option */ |
| if (code != ICMPV6_HDR_FIELD) { |
| break; |
| } |
| teli = parse_tlv_tnl_enc_lim(skb, skb->data); |
| |
| if (teli && teli == ntohl(info) - 2) { |
| tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; |
| if (tel->encap_limit == 0) { |
| if (net_ratelimit()) |
| printk(KERN_WARNING |
| "%s: Too small encapsulation " |
| "limit or routing loop in " |
| "tunnel!\n", t->parms.name); |
| rel_msg = 1; |
| } |
| } |
| break; |
| case ICMPV6_PKT_TOOBIG: |
| mtu = ntohl(info) - offset; |
| if (mtu < IPV6_MIN_MTU) |
| mtu = IPV6_MIN_MTU; |
| t->dev->mtu = mtu; |
| |
| if ((len = sizeof (*ipv6h) + ntohs(ipv6h->payload_len)) > mtu) { |
| rel_type = ICMPV6_PKT_TOOBIG; |
| rel_code = 0; |
| rel_info = mtu; |
| rel_msg = 1; |
| } |
| break; |
| } |
| if (rel_msg && pskb_may_pull(skb, offset + sizeof (*ipv6h))) { |
| struct rt6_info *rt; |
| struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); |
| if (!skb2) |
| goto out; |
| |
| dst_release(skb2->dst); |
| skb2->dst = NULL; |
| skb_pull(skb2, offset); |
| skb2->nh.raw = skb2->data; |
| |
| /* Try to guess incoming interface */ |
| rt = rt6_lookup(&skb2->nh.ipv6h->saddr, NULL, 0, 0); |
| |
| if (rt && rt->rt6i_dev) |
| skb2->dev = rt->rt6i_dev; |
| |
| icmpv6_send(skb2, rel_type, rel_code, rel_info, skb2->dev); |
| |
| if (rt) |
| dst_release(&rt->u.dst); |
| |
| kfree_skb(skb2); |
| } |
| out: |
| read_unlock(&ip6ip6_lock); |
| return err; |
| } |
| |
| static inline void ip6ip6_ecn_decapsulate(struct ipv6hdr *outer_iph, |
| struct sk_buff *skb) |
| { |
| struct ipv6hdr *inner_iph = skb->nh.ipv6h; |
| |
| if (INET_ECN_is_ce(ipv6_get_dsfield(outer_iph))) |
| IP6_ECN_set_ce(inner_iph); |
| } |
| |
| /** |
| * ip6ip6_rcv - decapsulate IPv6 packet and retransmit it locally |
| * @skb: received socket buffer |
| * |
| * Return: 0 |
| **/ |
| |
| static int |
| ip6ip6_rcv(struct sk_buff *skb) |
| { |
| struct ipv6hdr *ipv6h; |
| struct ip6_tnl *t; |
| |
| ipv6h = skb->nh.ipv6h; |
| |
| read_lock(&ip6ip6_lock); |
| |
| if ((t = ip6ip6_tnl_lookup(&ipv6h->saddr, &ipv6h->daddr)) != NULL) { |
| if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
| read_unlock(&ip6ip6_lock); |
| goto discard; |
| } |
| |
| if (!(t->parms.flags & IP6_TNL_F_CAP_RCV)) { |
| t->stat.rx_dropped++; |
| read_unlock(&ip6ip6_lock); |
| goto discard; |
| } |
| secpath_reset(skb); |
| skb->mac.raw = skb->nh.raw; |
| skb->nh.raw = skb->data; |
| skb->protocol = htons(ETH_P_IPV6); |
| skb->pkt_type = PACKET_HOST; |
| memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); |
| skb->dev = t->dev; |
| dst_release(skb->dst); |
| skb->dst = NULL; |
| nf_reset(skb); |
| if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) |
| ipv6_copy_dscp(ipv6h, skb->nh.ipv6h); |
| ip6ip6_ecn_decapsulate(ipv6h, skb); |
| t->stat.rx_packets++; |
| t->stat.rx_bytes += skb->len; |
| netif_rx(skb); |
| read_unlock(&ip6ip6_lock); |
| return 0; |
| } |
| read_unlock(&ip6ip6_lock); |
| return 1; |
| |
| discard: |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| static inline struct ipv6_txoptions *create_tel(__u8 encap_limit) |
| { |
| struct ipv6_tlv_tnl_enc_lim *tel; |
| struct ipv6_txoptions *opt; |
| __u8 *raw; |
| |
| int opt_len = sizeof(*opt) + 8; |
| |
| if (!(opt = kzalloc(opt_len, GFP_ATOMIC))) { |
| return NULL; |
| } |
| opt->tot_len = opt_len; |
| opt->dst0opt = (struct ipv6_opt_hdr *) (opt + 1); |
| opt->opt_nflen = 8; |
| |
| tel = (struct ipv6_tlv_tnl_enc_lim *) (opt->dst0opt + 1); |
| tel->type = IPV6_TLV_TNL_ENCAP_LIMIT; |
| tel->length = 1; |
| tel->encap_limit = encap_limit; |
| |
| raw = (__u8 *) opt->dst0opt; |
| raw[5] = IPV6_TLV_PADN; |
| raw[6] = 1; |
| |
| return opt; |
| } |
| |
| /** |
| * ip6ip6_tnl_addr_conflict - compare packet addresses to tunnel's own |
| * @t: the outgoing tunnel device |
| * @hdr: IPv6 header from the incoming packet |
| * |
| * Description: |
| * Avoid trivial tunneling loop by checking that tunnel exit-point |
| * doesn't match source of incoming packet. |
| * |
| * Return: |
| * 1 if conflict, |
| * 0 else |
| **/ |
| |
| static inline int |
| ip6ip6_tnl_addr_conflict(struct ip6_tnl *t, struct ipv6hdr *hdr) |
| { |
| return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); |
| } |
| |
| /** |
| * ip6ip6_tnl_xmit - encapsulate packet and send |
| * @skb: the outgoing socket buffer |
| * @dev: the outgoing tunnel device |
| * |
| * Description: |
| * Build new header and do some sanity checks on the packet before sending |
| * it. |
| * |
| * Return: |
| * 0 |
| **/ |
| |
| static int |
| ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct net_device_stats *stats = &t->stat; |
| struct ipv6hdr *ipv6h = skb->nh.ipv6h; |
| struct ipv6_txoptions *opt = NULL; |
| int encap_limit = -1; |
| __u16 offset; |
| struct flowi fl; |
| struct dst_entry *dst; |
| struct net_device *tdev; |
| int mtu; |
| int max_headroom = sizeof(struct ipv6hdr); |
| u8 proto; |
| int err; |
| int pkt_len; |
| int dsfield; |
| |
| if (t->recursion++) { |
| stats->collisions++; |
| goto tx_err; |
| } |
| if (skb->protocol != htons(ETH_P_IPV6) || |
| !(t->parms.flags & IP6_TNL_F_CAP_XMIT) || |
| ip6ip6_tnl_addr_conflict(t, ipv6h)) { |
| goto tx_err; |
| } |
| if ((offset = parse_tlv_tnl_enc_lim(skb, skb->nh.raw)) > 0) { |
| struct ipv6_tlv_tnl_enc_lim *tel; |
| tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->nh.raw[offset]; |
| if (tel->encap_limit == 0) { |
| icmpv6_send(skb, ICMPV6_PARAMPROB, |
| ICMPV6_HDR_FIELD, offset + 2, skb->dev); |
| goto tx_err; |
| } |
| encap_limit = tel->encap_limit - 1; |
| } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) { |
| encap_limit = t->parms.encap_limit; |
| } |
| memcpy(&fl, &t->fl, sizeof (fl)); |
| proto = fl.proto; |
| |
| dsfield = ipv6_get_dsfield(ipv6h); |
| if ((t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)) |
| fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); |
| if ((t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)) |
| fl.fl6_flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); |
| |
| if (encap_limit >= 0 && (opt = create_tel(encap_limit)) == NULL) |
| goto tx_err; |
| |
| if ((dst = ip6_tnl_dst_check(t)) != NULL) |
| dst_hold(dst); |
| else { |
| dst = ip6_route_output(NULL, &fl); |
| |
| if (dst->error || xfrm_lookup(&dst, &fl, NULL, 0) < 0) |
| goto tx_err_link_failure; |
| } |
| |
| tdev = dst->dev; |
| |
| if (tdev == dev) { |
| stats->collisions++; |
| if (net_ratelimit()) |
| printk(KERN_WARNING |
| "%s: Local routing loop detected!\n", |
| t->parms.name); |
| goto tx_err_dst_release; |
| } |
| mtu = dst_mtu(dst) - sizeof (*ipv6h); |
| if (opt) { |
| max_headroom += 8; |
| mtu -= 8; |
| } |
| if (mtu < IPV6_MIN_MTU) |
| mtu = IPV6_MIN_MTU; |
| if (skb->dst && mtu < dst_mtu(skb->dst)) { |
| struct rt6_info *rt = (struct rt6_info *) skb->dst; |
| rt->rt6i_flags |= RTF_MODIFIED; |
| rt->u.dst.metrics[RTAX_MTU-1] = mtu; |
| } |
| if (skb->len > mtu) { |
| icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, dev); |
| goto tx_err_dst_release; |
| } |
| |
| /* |
| * Okay, now see if we can stuff it in the buffer as-is. |
| */ |
| max_headroom += LL_RESERVED_SPACE(tdev); |
| |
| if (skb_headroom(skb) < max_headroom || |
| skb_cloned(skb) || skb_shared(skb)) { |
| struct sk_buff *new_skb; |
| |
| if (!(new_skb = skb_realloc_headroom(skb, max_headroom))) |
| goto tx_err_dst_release; |
| |
| if (skb->sk) |
| skb_set_owner_w(new_skb, skb->sk); |
| kfree_skb(skb); |
| skb = new_skb; |
| } |
| dst_release(skb->dst); |
| skb->dst = dst_clone(dst); |
| |
| skb->h.raw = skb->nh.raw; |
| |
| if (opt) |
| ipv6_push_nfrag_opts(skb, opt, &proto, NULL); |
| |
| skb->nh.raw = skb_push(skb, sizeof(struct ipv6hdr)); |
| ipv6h = skb->nh.ipv6h; |
| *(__be32*)ipv6h = fl.fl6_flowlabel | htonl(0x60000000); |
| dsfield = INET_ECN_encapsulate(0, dsfield); |
| ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield); |
| ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); |
| ipv6h->hop_limit = t->parms.hop_limit; |
| ipv6h->nexthdr = proto; |
| ipv6_addr_copy(&ipv6h->saddr, &fl.fl6_src); |
| ipv6_addr_copy(&ipv6h->daddr, &fl.fl6_dst); |
| nf_reset(skb); |
| pkt_len = skb->len; |
| err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, |
| skb->dst->dev, dst_output); |
| |
| if (net_xmit_eval(err) == 0) { |
| stats->tx_bytes += pkt_len; |
| stats->tx_packets++; |
| } else { |
| stats->tx_errors++; |
| stats->tx_aborted_errors++; |
| } |
| ip6_tnl_dst_store(t, dst); |
| |
| kfree(opt); |
| |
| t->recursion--; |
| return 0; |
| tx_err_link_failure: |
| stats->tx_carrier_errors++; |
| dst_link_failure(skb); |
| tx_err_dst_release: |
| dst_release(dst); |
| kfree(opt); |
| tx_err: |
| stats->tx_errors++; |
| stats->tx_dropped++; |
| kfree_skb(skb); |
| t->recursion--; |
| return 0; |
| } |
| |
| static void ip6_tnl_set_cap(struct ip6_tnl *t) |
| { |
| struct ip6_tnl_parm *p = &t->parms; |
| struct in6_addr *laddr = &p->laddr; |
| struct in6_addr *raddr = &p->raddr; |
| int ltype = ipv6_addr_type(laddr); |
| int rtype = ipv6_addr_type(raddr); |
| |
| p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV); |
| |
| if (ltype != IPV6_ADDR_ANY && rtype != IPV6_ADDR_ANY && |
| ((ltype|rtype) & |
| (IPV6_ADDR_UNICAST| |
| IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL| |
| IPV6_ADDR_MAPPED|IPV6_ADDR_RESERVED)) == IPV6_ADDR_UNICAST) { |
| struct net_device *ldev = NULL; |
| int l_ok = 1; |
| int r_ok = 1; |
| |
| if (p->link) |
| ldev = dev_get_by_index(p->link); |
| |
| if (ltype&IPV6_ADDR_UNICAST && !ipv6_chk_addr(laddr, ldev, 0)) |
| l_ok = 0; |
| |
| if (rtype&IPV6_ADDR_UNICAST && ipv6_chk_addr(raddr, NULL, 0)) |
| r_ok = 0; |
| |
| if (l_ok && r_ok) { |
| if (ltype&IPV6_ADDR_UNICAST) |
| p->flags |= IP6_TNL_F_CAP_XMIT; |
| if (rtype&IPV6_ADDR_UNICAST) |
| p->flags |= IP6_TNL_F_CAP_RCV; |
| } |
| if (ldev) |
| dev_put(ldev); |
| } |
| } |
| |
| static void ip6ip6_tnl_link_config(struct ip6_tnl *t) |
| { |
| struct net_device *dev = t->dev; |
| struct ip6_tnl_parm *p = &t->parms; |
| struct flowi *fl = &t->fl; |
| |
| memcpy(&dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); |
| memcpy(&dev->broadcast, &p->raddr, sizeof(struct in6_addr)); |
| |
| /* Set up flowi template */ |
| ipv6_addr_copy(&fl->fl6_src, &p->laddr); |
| ipv6_addr_copy(&fl->fl6_dst, &p->raddr); |
| fl->oif = p->link; |
| fl->fl6_flowlabel = 0; |
| |
| if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) |
| fl->fl6_flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; |
| if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) |
| fl->fl6_flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; |
| |
| ip6_tnl_set_cap(t); |
| |
| if (p->flags&IP6_TNL_F_CAP_XMIT && p->flags&IP6_TNL_F_CAP_RCV) |
| dev->flags |= IFF_POINTOPOINT; |
| else |
| dev->flags &= ~IFF_POINTOPOINT; |
| |
| dev->iflink = p->link; |
| |
| if (p->flags & IP6_TNL_F_CAP_XMIT) { |
| struct rt6_info *rt = rt6_lookup(&p->raddr, &p->laddr, |
| p->link, 0); |
| |
| if (rt == NULL) |
| return; |
| |
| if (rt->rt6i_dev) { |
| dev->hard_header_len = rt->rt6i_dev->hard_header_len + |
| sizeof (struct ipv6hdr); |
| |
| dev->mtu = rt->rt6i_dev->mtu - sizeof (struct ipv6hdr); |
| |
| if (dev->mtu < IPV6_MIN_MTU) |
| dev->mtu = IPV6_MIN_MTU; |
| } |
| dst_release(&rt->u.dst); |
| } |
| } |
| |
| /** |
| * ip6ip6_tnl_change - update the tunnel parameters |
| * @t: tunnel to be changed |
| * @p: tunnel configuration parameters |
| * @active: != 0 if tunnel is ready for use |
| * |
| * Description: |
| * ip6ip6_tnl_change() updates the tunnel parameters |
| **/ |
| |
| static int |
| ip6ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p) |
| { |
| ipv6_addr_copy(&t->parms.laddr, &p->laddr); |
| ipv6_addr_copy(&t->parms.raddr, &p->raddr); |
| t->parms.flags = p->flags; |
| t->parms.hop_limit = p->hop_limit; |
| t->parms.encap_limit = p->encap_limit; |
| t->parms.flowinfo = p->flowinfo; |
| t->parms.link = p->link; |
| ip6_tnl_dst_reset(t); |
| ip6ip6_tnl_link_config(t); |
| return 0; |
| } |
| |
| /** |
| * ip6ip6_tnl_ioctl - configure ipv6 tunnels from userspace |
| * @dev: virtual device associated with tunnel |
| * @ifr: parameters passed from userspace |
| * @cmd: command to be performed |
| * |
| * Description: |
| * ip6ip6_tnl_ioctl() is used for managing IPv6 tunnels |
| * from userspace. |
| * |
| * The possible commands are the following: |
| * %SIOCGETTUNNEL: get tunnel parameters for device |
| * %SIOCADDTUNNEL: add tunnel matching given tunnel parameters |
| * %SIOCCHGTUNNEL: change tunnel parameters to those given |
| * %SIOCDELTUNNEL: delete tunnel |
| * |
| * The fallback device "ip6tnl0", created during module |
| * initialization, can be used for creating other tunnel devices. |
| * |
| * Return: |
| * 0 on success, |
| * %-EFAULT if unable to copy data to or from userspace, |
| * %-EPERM if current process hasn't %CAP_NET_ADMIN set |
| * %-EINVAL if passed tunnel parameters are invalid, |
| * %-EEXIST if changing a tunnel's parameters would cause a conflict |
| * %-ENODEV if attempting to change or delete a nonexisting device |
| **/ |
| |
| static int |
| ip6ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
| { |
| int err = 0; |
| int create; |
| struct ip6_tnl_parm p; |
| struct ip6_tnl *t = NULL; |
| |
| switch (cmd) { |
| case SIOCGETTUNNEL: |
| if (dev == ip6ip6_fb_tnl_dev) { |
| if (copy_from_user(&p, |
| ifr->ifr_ifru.ifru_data, |
| sizeof (p))) { |
| err = -EFAULT; |
| break; |
| } |
| if ((err = ip6ip6_tnl_locate(&p, &t, 0)) == -ENODEV) |
| t = netdev_priv(dev); |
| else if (err) |
| break; |
| } else |
| 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; |
| create = (cmd == SIOCADDTUNNEL); |
| if (!capable(CAP_NET_ADMIN)) |
| break; |
| if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { |
| err = -EFAULT; |
| break; |
| } |
| if (!create && dev != ip6ip6_fb_tnl_dev) { |
| t = netdev_priv(dev); |
| } |
| if (!t && (err = ip6ip6_tnl_locate(&p, &t, create))) { |
| break; |
| } |
| if (cmd == SIOCCHGTUNNEL) { |
| if (t->dev != dev) { |
| err = -EEXIST; |
| break; |
| } |
| ip6ip6_tnl_unlink(t); |
| err = ip6ip6_tnl_change(t, &p); |
| ip6ip6_tnl_link(t); |
| netdev_state_change(dev); |
| } |
| if (copy_to_user(ifr->ifr_ifru.ifru_data, |
| &t->parms, sizeof (p))) { |
| err = -EFAULT; |
| } else { |
| err = 0; |
| } |
| break; |
| case SIOCDELTUNNEL: |
| err = -EPERM; |
| if (!capable(CAP_NET_ADMIN)) |
| break; |
| |
| if (dev == ip6ip6_fb_tnl_dev) { |
| if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, |
| sizeof (p))) { |
| err = -EFAULT; |
| break; |
| } |
| err = ip6ip6_tnl_locate(&p, &t, 0); |
| if (err) |
| break; |
| if (t == netdev_priv(ip6ip6_fb_tnl_dev)) { |
| err = -EPERM; |
| break; |
| } |
| } else { |
| t = netdev_priv(dev); |
| } |
| err = unregister_netdevice(t->dev); |
| break; |
| default: |
| err = -EINVAL; |
| } |
| return err; |
| } |
| |
| /** |
| * ip6ip6_tnl_get_stats - return the stats for tunnel device |
| * @dev: virtual device associated with tunnel |
| * |
| * Return: stats for device |
| **/ |
| |
| static struct net_device_stats * |
| ip6ip6_tnl_get_stats(struct net_device *dev) |
| { |
| return &(((struct ip6_tnl *)netdev_priv(dev))->stat); |
| } |
| |
| /** |
| * ip6ip6_tnl_change_mtu - change mtu manually for tunnel device |
| * @dev: virtual device associated with tunnel |
| * @new_mtu: the new mtu |
| * |
| * Return: |
| * 0 on success, |
| * %-EINVAL if mtu too small |
| **/ |
| |
| static int |
| ip6ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) |
| { |
| if (new_mtu < IPV6_MIN_MTU) { |
| return -EINVAL; |
| } |
| dev->mtu = new_mtu; |
| return 0; |
| } |
| |
| /** |
| * ip6ip6_tnl_dev_setup - setup virtual tunnel device |
| * @dev: virtual device associated with tunnel |
| * |
| * Description: |
| * Initialize function pointers and device parameters |
| **/ |
| |
| static void ip6ip6_tnl_dev_setup(struct net_device *dev) |
| { |
| SET_MODULE_OWNER(dev); |
| dev->uninit = ip6ip6_tnl_dev_uninit; |
| dev->destructor = free_netdev; |
| dev->hard_start_xmit = ip6ip6_tnl_xmit; |
| dev->get_stats = ip6ip6_tnl_get_stats; |
| dev->do_ioctl = ip6ip6_tnl_ioctl; |
| dev->change_mtu = ip6ip6_tnl_change_mtu; |
| |
| dev->type = ARPHRD_TUNNEL6; |
| dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); |
| dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); |
| dev->flags |= IFF_NOARP; |
| dev->addr_len = sizeof(struct in6_addr); |
| } |
| |
| |
| /** |
| * ip6ip6_tnl_dev_init_gen - general initializer for all tunnel devices |
| * @dev: virtual device associated with tunnel |
| **/ |
| |
| static inline void |
| ip6ip6_tnl_dev_init_gen(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| t->fl.proto = IPPROTO_IPV6; |
| t->dev = dev; |
| strcpy(t->parms.name, dev->name); |
| } |
| |
| /** |
| * ip6ip6_tnl_dev_init - initializer for all non fallback tunnel devices |
| * @dev: virtual device associated with tunnel |
| **/ |
| |
| static int |
| ip6ip6_tnl_dev_init(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| ip6ip6_tnl_dev_init_gen(dev); |
| ip6ip6_tnl_link_config(t); |
| return 0; |
| } |
| |
| /** |
| * ip6ip6_fb_tnl_dev_init - initializer for fallback tunnel device |
| * @dev: fallback device |
| * |
| * Return: 0 |
| **/ |
| |
| static int |
| ip6ip6_fb_tnl_dev_init(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| ip6ip6_tnl_dev_init_gen(dev); |
| dev_hold(dev); |
| tnls_wc[0] = t; |
| return 0; |
| } |
| |
| static struct xfrm6_tunnel ip6ip6_handler = { |
| .handler = ip6ip6_rcv, |
| .err_handler = ip6ip6_err, |
| .priority = 1, |
| }; |
| |
| /** |
| * ip6_tunnel_init - register protocol and reserve needed resources |
| * |
| * Return: 0 on success |
| **/ |
| |
| static int __init ip6_tunnel_init(void) |
| { |
| int err; |
| |
| if (xfrm6_tunnel_register(&ip6ip6_handler)) { |
| printk(KERN_ERR "ip6ip6 init: can't register tunnel\n"); |
| return -EAGAIN; |
| } |
| ip6ip6_fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", |
| ip6ip6_tnl_dev_setup); |
| |
| if (!ip6ip6_fb_tnl_dev) { |
| err = -ENOMEM; |
| goto fail; |
| } |
| ip6ip6_fb_tnl_dev->init = ip6ip6_fb_tnl_dev_init; |
| |
| if ((err = register_netdev(ip6ip6_fb_tnl_dev))) { |
| free_netdev(ip6ip6_fb_tnl_dev); |
| goto fail; |
| } |
| return 0; |
| fail: |
| xfrm6_tunnel_deregister(&ip6ip6_handler); |
| return err; |
| } |
| |
| static void __exit ip6ip6_destroy_tunnels(void) |
| { |
| int h; |
| struct ip6_tnl *t; |
| |
| for (h = 0; h < HASH_SIZE; h++) { |
| while ((t = tnls_r_l[h]) != NULL) |
| unregister_netdevice(t->dev); |
| } |
| |
| t = tnls_wc[0]; |
| unregister_netdevice(t->dev); |
| } |
| |
| /** |
| * ip6_tunnel_cleanup - free resources and unregister protocol |
| **/ |
| |
| static void __exit ip6_tunnel_cleanup(void) |
| { |
| if (xfrm6_tunnel_deregister(&ip6ip6_handler)) |
| printk(KERN_INFO "ip6ip6 close: can't deregister tunnel\n"); |
| |
| rtnl_lock(); |
| ip6ip6_destroy_tunnels(); |
| rtnl_unlock(); |
| } |
| |
| module_init(ip6_tunnel_init); |
| module_exit(ip6_tunnel_cleanup); |