| /* |
| * IPv6 tunneling device |
| * Linux INET6 implementation |
| * |
| * Authors: |
| * Ville Nuorvala <vnuorval@tcs.hut.fi> |
| * Yasuyuki Kozakai <kozakai@linux-ipv6.org> |
| * |
| * Based on: |
| * linux/net/ipv6/sit.c and linux/net/ipv4/ipip.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. |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/module.h> |
| #include <linux/capability.h> |
| #include <linux/errno.h> |
| #include <linux/types.h> |
| #include <linux/sockios.h> |
| #include <linux/icmp.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 <linux/slab.h> |
| #include <linux/hash.h> |
| #include <linux/etherdevice.h> |
| |
| #include <asm/uaccess.h> |
| #include <linux/atomic.h> |
| |
| #include <net/icmp.h> |
| #include <net/ip.h> |
| #include <net/ip_tunnels.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> |
| #include <net/net_namespace.h> |
| #include <net/netns/generic.h> |
| |
| MODULE_AUTHOR("Ville Nuorvala"); |
| MODULE_DESCRIPTION("IPv6 tunneling device"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS_NETDEV("ip6tnl0"); |
| |
| #ifdef IP6_TNL_DEBUG |
| #define IP6_TNL_TRACE(x...) pr_debug("%s:" x "\n", __func__) |
| #else |
| #define IP6_TNL_TRACE(x...) do {;} while(0) |
| #endif |
| |
| #define IPV6_TCLASS_MASK (IPV6_FLOWINFO_MASK & ~IPV6_FLOWLABEL_MASK) |
| #define IPV6_TCLASS_SHIFT 20 |
| |
| #define HASH_SIZE_SHIFT 5 |
| #define HASH_SIZE (1 << HASH_SIZE_SHIFT) |
| |
| static bool log_ecn_error = true; |
| module_param(log_ecn_error, bool, 0644); |
| MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); |
| |
| static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2) |
| { |
| u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2); |
| |
| return hash_32(hash, HASH_SIZE_SHIFT); |
| } |
| |
| static int ip6_tnl_dev_init(struct net_device *dev); |
| static void ip6_tnl_dev_setup(struct net_device *dev); |
| static struct rtnl_link_ops ip6_link_ops __read_mostly; |
| |
| static int ip6_tnl_net_id __read_mostly; |
| struct ip6_tnl_net { |
| /* the IPv6 tunnel fallback device */ |
| struct net_device *fb_tnl_dev; |
| /* lists for storing tunnels in use */ |
| struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE]; |
| struct ip6_tnl __rcu *tnls_wc[1]; |
| struct ip6_tnl __rcu **tnls[2]; |
| }; |
| |
| static struct net_device_stats *ip6_get_stats(struct net_device *dev) |
| { |
| struct pcpu_tstats sum = { 0 }; |
| int i; |
| |
| for_each_possible_cpu(i) { |
| const struct pcpu_tstats *tstats = per_cpu_ptr(dev->tstats, i); |
| |
| sum.rx_packets += tstats->rx_packets; |
| sum.rx_bytes += tstats->rx_bytes; |
| sum.tx_packets += tstats->tx_packets; |
| sum.tx_bytes += tstats->tx_bytes; |
| } |
| dev->stats.rx_packets = sum.rx_packets; |
| dev->stats.rx_bytes = sum.rx_bytes; |
| dev->stats.tx_packets = sum.tx_packets; |
| dev->stats.tx_bytes = sum.tx_bytes; |
| return &dev->stats; |
| } |
| |
| /* |
| * Locking : hash tables are protected by RCU and RTNL |
| */ |
| |
| 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; |
| } |
| EXPORT_SYMBOL_GPL(ip6_tnl_dst_check); |
| |
| void ip6_tnl_dst_reset(struct ip6_tnl *t) |
| { |
| dst_release(t->dst_cache); |
| t->dst_cache = NULL; |
| } |
| EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset); |
| |
| 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; |
| } |
| EXPORT_SYMBOL_GPL(ip6_tnl_dst_store); |
| |
| /** |
| * ip6_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 |
| **/ |
| |
| #define for_each_ip6_tunnel_rcu(start) \ |
| for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) |
| |
| static struct ip6_tnl * |
| ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_addr *local) |
| { |
| unsigned int hash = HASH(remote, local); |
| struct ip6_tnl *t; |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| |
| for_each_ip6_tunnel_rcu(ip6n->tnls_r_l[hash]) { |
| if (ipv6_addr_equal(local, &t->parms.laddr) && |
| ipv6_addr_equal(remote, &t->parms.raddr) && |
| (t->dev->flags & IFF_UP)) |
| return t; |
| } |
| t = rcu_dereference(ip6n->tnls_wc[0]); |
| if (t && (t->dev->flags & IFF_UP)) |
| return t; |
| |
| return NULL; |
| } |
| |
| /** |
| * ip6_tnl_bucket - get head of list matching given tunnel parameters |
| * @p: parameters containing tunnel end-points |
| * |
| * Description: |
| * ip6_tnl_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 __rcu ** |
| ip6_tnl_bucket(struct ip6_tnl_net *ip6n, const struct __ip6_tnl_parm *p) |
| { |
| const struct in6_addr *remote = &p->raddr; |
| const struct in6_addr *local = &p->laddr; |
| unsigned int h = 0; |
| int prio = 0; |
| |
| if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) { |
| prio = 1; |
| h = HASH(remote, local); |
| } |
| return &ip6n->tnls[prio][h]; |
| } |
| |
| /** |
| * ip6_tnl_link - add tunnel to hash table |
| * @t: tunnel to be added |
| **/ |
| |
| static void |
| ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) |
| { |
| struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms); |
| |
| rcu_assign_pointer(t->next , rtnl_dereference(*tp)); |
| rcu_assign_pointer(*tp, t); |
| } |
| |
| /** |
| * ip6_tnl_unlink - remove tunnel from hash table |
| * @t: tunnel to be removed |
| **/ |
| |
| static void |
| ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t) |
| { |
| struct ip6_tnl __rcu **tp; |
| struct ip6_tnl *iter; |
| |
| for (tp = ip6_tnl_bucket(ip6n, &t->parms); |
| (iter = rtnl_dereference(*tp)) != NULL; |
| tp = &iter->next) { |
| if (t == iter) { |
| rcu_assign_pointer(*tp, t->next); |
| break; |
| } |
| } |
| } |
| |
| static void ip6_dev_free(struct net_device *dev) |
| { |
| free_percpu(dev->tstats); |
| free_netdev(dev); |
| } |
| |
| static int ip6_tnl_create2(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct net *net = dev_net(dev); |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| int err; |
| |
| t = netdev_priv(dev); |
| err = ip6_tnl_dev_init(dev); |
| if (err < 0) |
| goto out; |
| |
| err = register_netdevice(dev); |
| if (err < 0) |
| goto out; |
| |
| strcpy(t->parms.name, dev->name); |
| dev->rtnl_link_ops = &ip6_link_ops; |
| |
| dev_hold(dev); |
| ip6_tnl_link(ip6n, t); |
| return 0; |
| |
| out: |
| return err; |
| } |
| |
| /** |
| * ip6_tnl_create - create a new tunnel |
| * @p: tunnel parameters |
| * @pt: pointer to new tunnel |
| * |
| * Description: |
| * Create tunnel matching given parameters. |
| * |
| * Return: |
| * created tunnel or NULL |
| **/ |
| |
| static struct ip6_tnl *ip6_tnl_create(struct net *net, struct __ip6_tnl_parm *p) |
| { |
| struct net_device *dev; |
| struct ip6_tnl *t; |
| char name[IFNAMSIZ]; |
| int err; |
| |
| if (p->name[0]) |
| strlcpy(name, p->name, IFNAMSIZ); |
| else |
| sprintf(name, "ip6tnl%%d"); |
| |
| dev = alloc_netdev(sizeof (*t), name, ip6_tnl_dev_setup); |
| if (dev == NULL) |
| goto failed; |
| |
| dev_net_set(dev, net); |
| |
| t = netdev_priv(dev); |
| t->parms = *p; |
| t->net = dev_net(dev); |
| err = ip6_tnl_create2(dev); |
| if (err < 0) |
| goto failed_free; |
| |
| return t; |
| |
| failed_free: |
| ip6_dev_free(dev); |
| failed: |
| return NULL; |
| } |
| |
| /** |
| * ip6_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: |
| * ip6_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: |
| * matching tunnel or NULL |
| **/ |
| |
| static struct ip6_tnl *ip6_tnl_locate(struct net *net, |
| struct __ip6_tnl_parm *p, int create) |
| { |
| const struct in6_addr *remote = &p->raddr; |
| const struct in6_addr *local = &p->laddr; |
| struct ip6_tnl __rcu **tp; |
| struct ip6_tnl *t; |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| |
| for (tp = ip6_tnl_bucket(ip6n, p); |
| (t = rtnl_dereference(*tp)) != NULL; |
| tp = &t->next) { |
| if (ipv6_addr_equal(local, &t->parms.laddr) && |
| ipv6_addr_equal(remote, &t->parms.raddr)) |
| return t; |
| } |
| if (!create) |
| return NULL; |
| return ip6_tnl_create(net, p); |
| } |
| |
| /** |
| * ip6_tnl_dev_uninit - tunnel device uninitializer |
| * @dev: the device to be destroyed |
| * |
| * Description: |
| * ip6_tnl_dev_uninit() removes tunnel from its list |
| **/ |
| |
| static void |
| ip6_tnl_dev_uninit(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct net *net = t->net; |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| |
| if (dev == ip6n->fb_tnl_dev) |
| RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); |
| else |
| ip6_tnl_unlink(ip6n, 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 |
| **/ |
| |
| __u16 ip6_tnl_parse_tlv_enc_lim(struct sk_buff *skb, __u8 *raw) |
| { |
| const struct ipv6hdr *ipv6h = (const 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; |
| } |
| EXPORT_SYMBOL(ip6_tnl_parse_tlv_enc_lim); |
| |
| /** |
| * ip6_tnl_err - tunnel error handler |
| * |
| * Description: |
| * ip6_tnl_err() should handle errors in the tunnel according |
| * to the specifications in RFC 2473. |
| **/ |
| |
| static int |
| ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt, |
| u8 *type, u8 *code, int *msg, __u32 *info, int offset) |
| { |
| const struct ipv6hdr *ipv6h = (const struct ipv6hdr *) skb->data; |
| struct ip6_tnl *t; |
| int rel_msg = 0; |
| u8 rel_type = ICMPV6_DEST_UNREACH; |
| u8 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. */ |
| |
| rcu_read_lock(); |
| if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->daddr, |
| &ipv6h->saddr)) == NULL) |
| goto out; |
| |
| if (t->parms.proto != ipproto && t->parms.proto != 0) |
| goto out; |
| |
| err = 0; |
| |
| switch (*type) { |
| __u32 teli; |
| struct ipv6_tlv_tnl_enc_lim *tel; |
| __u32 mtu; |
| case ICMPV6_DEST_UNREACH: |
| net_warn_ratelimited("%s: Path to destination invalid or inactive!\n", |
| t->parms.name); |
| rel_msg = 1; |
| break; |
| case ICMPV6_TIME_EXCEED: |
| if ((*code) == ICMPV6_EXC_HOPLIMIT) { |
| net_warn_ratelimited("%s: Too small hop limit or routing loop in tunnel!\n", |
| t->parms.name); |
| rel_msg = 1; |
| } |
| break; |
| case ICMPV6_PARAMPROB: |
| teli = 0; |
| if ((*code) == ICMPV6_HDR_FIELD) |
| teli = ip6_tnl_parse_tlv_enc_lim(skb, skb->data); |
| |
| if (teli && teli == *info - 2) { |
| tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->data[teli]; |
| if (tel->encap_limit == 0) { |
| net_warn_ratelimited("%s: Too small encapsulation limit or routing loop in tunnel!\n", |
| t->parms.name); |
| rel_msg = 1; |
| } |
| } else { |
| net_warn_ratelimited("%s: Recipient unable to parse tunneled packet!\n", |
| t->parms.name); |
| } |
| break; |
| case ICMPV6_PKT_TOOBIG: |
| mtu = *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; |
| } |
| |
| *type = rel_type; |
| *code = rel_code; |
| *info = rel_info; |
| *msg = rel_msg; |
| |
| out: |
| rcu_read_unlock(); |
| return err; |
| } |
| |
| static int |
| ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| u8 type, u8 code, int offset, __be32 info) |
| { |
| int rel_msg = 0; |
| u8 rel_type = type; |
| u8 rel_code = code; |
| __u32 rel_info = ntohl(info); |
| int err; |
| struct sk_buff *skb2; |
| const struct iphdr *eiph; |
| struct rtable *rt; |
| struct flowi4 fl4; |
| |
| err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code, |
| &rel_msg, &rel_info, offset); |
| if (err < 0) |
| return err; |
| |
| if (rel_msg == 0) |
| return 0; |
| |
| switch (rel_type) { |
| case ICMPV6_DEST_UNREACH: |
| if (rel_code != ICMPV6_ADDR_UNREACH) |
| return 0; |
| rel_type = ICMP_DEST_UNREACH; |
| rel_code = ICMP_HOST_UNREACH; |
| break; |
| case ICMPV6_PKT_TOOBIG: |
| if (rel_code != 0) |
| return 0; |
| rel_type = ICMP_DEST_UNREACH; |
| rel_code = ICMP_FRAG_NEEDED; |
| break; |
| case NDISC_REDIRECT: |
| rel_type = ICMP_REDIRECT; |
| rel_code = ICMP_REDIR_HOST; |
| default: |
| return 0; |
| } |
| |
| if (!pskb_may_pull(skb, offset + sizeof(struct iphdr))) |
| return 0; |
| |
| skb2 = skb_clone(skb, GFP_ATOMIC); |
| if (!skb2) |
| return 0; |
| |
| skb_dst_drop(skb2); |
| |
| skb_pull(skb2, offset); |
| skb_reset_network_header(skb2); |
| eiph = ip_hdr(skb2); |
| |
| /* Try to guess incoming interface */ |
| rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, |
| eiph->saddr, 0, |
| 0, 0, |
| IPPROTO_IPIP, RT_TOS(eiph->tos), 0); |
| if (IS_ERR(rt)) |
| goto out; |
| |
| skb2->dev = rt->dst.dev; |
| |
| /* route "incoming" packet */ |
| if (rt->rt_flags & RTCF_LOCAL) { |
| ip_rt_put(rt); |
| rt = NULL; |
| rt = ip_route_output_ports(dev_net(skb->dev), &fl4, NULL, |
| eiph->daddr, eiph->saddr, |
| 0, 0, |
| IPPROTO_IPIP, |
| RT_TOS(eiph->tos), 0); |
| if (IS_ERR(rt) || |
| rt->dst.dev->type != ARPHRD_TUNNEL) { |
| if (!IS_ERR(rt)) |
| ip_rt_put(rt); |
| goto out; |
| } |
| skb_dst_set(skb2, &rt->dst); |
| } else { |
| ip_rt_put(rt); |
| if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, |
| skb2->dev) || |
| skb_dst(skb2)->dev->type != ARPHRD_TUNNEL) |
| goto out; |
| } |
| |
| /* change mtu on this route */ |
| if (rel_type == ICMP_DEST_UNREACH && rel_code == ICMP_FRAG_NEEDED) { |
| if (rel_info > dst_mtu(skb_dst(skb2))) |
| goto out; |
| |
| skb_dst(skb2)->ops->update_pmtu(skb_dst(skb2), NULL, skb2, rel_info); |
| } |
| if (rel_type == ICMP_REDIRECT) |
| skb_dst(skb2)->ops->redirect(skb_dst(skb2), NULL, skb2); |
| |
| icmp_send(skb2, rel_type, rel_code, htonl(rel_info)); |
| |
| out: |
| kfree_skb(skb2); |
| return 0; |
| } |
| |
| static int |
| ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, |
| u8 type, u8 code, int offset, __be32 info) |
| { |
| int rel_msg = 0; |
| u8 rel_type = type; |
| u8 rel_code = code; |
| __u32 rel_info = ntohl(info); |
| int err; |
| |
| err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code, |
| &rel_msg, &rel_info, offset); |
| if (err < 0) |
| return err; |
| |
| if (rel_msg && pskb_may_pull(skb, offset + sizeof(struct ipv6hdr))) { |
| struct rt6_info *rt; |
| struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); |
| |
| if (!skb2) |
| return 0; |
| |
| skb_dst_drop(skb2); |
| skb_pull(skb2, offset); |
| skb_reset_network_header(skb2); |
| |
| /* Try to guess incoming interface */ |
| rt = rt6_lookup(dev_net(skb->dev), &ipv6_hdr(skb2)->saddr, |
| NULL, 0, 0); |
| |
| if (rt && rt->dst.dev) |
| skb2->dev = rt->dst.dev; |
| |
| icmpv6_send(skb2, rel_type, rel_code, rel_info); |
| |
| ip6_rt_put(rt); |
| |
| kfree_skb(skb2); |
| } |
| |
| return 0; |
| } |
| |
| static int ip4ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, |
| const struct ipv6hdr *ipv6h, |
| struct sk_buff *skb) |
| { |
| __u8 dsfield = ipv6_get_dsfield(ipv6h) & ~INET_ECN_MASK; |
| |
| if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) |
| ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, dsfield); |
| |
| return IP6_ECN_decapsulate(ipv6h, skb); |
| } |
| |
| static int ip6ip6_dscp_ecn_decapsulate(const struct ip6_tnl *t, |
| const struct ipv6hdr *ipv6h, |
| struct sk_buff *skb) |
| { |
| if (t->parms.flags & IP6_TNL_F_RCV_DSCP_COPY) |
| ipv6_copy_dscp(ipv6_get_dsfield(ipv6h), ipv6_hdr(skb)); |
| |
| return IP6_ECN_decapsulate(ipv6h, skb); |
| } |
| |
| __u32 ip6_tnl_get_cap(struct ip6_tnl *t, |
| const struct in6_addr *laddr, |
| const struct in6_addr *raddr) |
| { |
| struct __ip6_tnl_parm *p = &t->parms; |
| int ltype = ipv6_addr_type(laddr); |
| int rtype = ipv6_addr_type(raddr); |
| __u32 flags = 0; |
| |
| if (ltype == IPV6_ADDR_ANY || rtype == IPV6_ADDR_ANY) { |
| flags = IP6_TNL_F_CAP_PER_PACKET; |
| } else if (ltype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && |
| rtype & (IPV6_ADDR_UNICAST|IPV6_ADDR_MULTICAST) && |
| !((ltype|rtype) & IPV6_ADDR_LOOPBACK) && |
| (!((ltype|rtype) & IPV6_ADDR_LINKLOCAL) || p->link)) { |
| if (ltype&IPV6_ADDR_UNICAST) |
| flags |= IP6_TNL_F_CAP_XMIT; |
| if (rtype&IPV6_ADDR_UNICAST) |
| flags |= IP6_TNL_F_CAP_RCV; |
| } |
| return flags; |
| } |
| EXPORT_SYMBOL(ip6_tnl_get_cap); |
| |
| /* called with rcu_read_lock() */ |
| int ip6_tnl_rcv_ctl(struct ip6_tnl *t, |
| const struct in6_addr *laddr, |
| const struct in6_addr *raddr) |
| { |
| struct __ip6_tnl_parm *p = &t->parms; |
| int ret = 0; |
| struct net *net = t->net; |
| |
| if ((p->flags & IP6_TNL_F_CAP_RCV) || |
| ((p->flags & IP6_TNL_F_CAP_PER_PACKET) && |
| (ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_RCV))) { |
| struct net_device *ldev = NULL; |
| |
| if (p->link) |
| ldev = dev_get_by_index_rcu(net, p->link); |
| |
| if ((ipv6_addr_is_multicast(laddr) || |
| likely(ipv6_chk_addr(net, laddr, ldev, 0))) && |
| likely(!ipv6_chk_addr(net, raddr, NULL, 0))) |
| ret = 1; |
| } |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(ip6_tnl_rcv_ctl); |
| |
| /** |
| * ip6_tnl_rcv - decapsulate IPv6 packet and retransmit it locally |
| * @skb: received socket buffer |
| * @protocol: ethernet protocol ID |
| * @dscp_ecn_decapsulate: the function to decapsulate DSCP code and ECN |
| * |
| * Return: 0 |
| **/ |
| |
| static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol, |
| __u8 ipproto, |
| int (*dscp_ecn_decapsulate)(const struct ip6_tnl *t, |
| const struct ipv6hdr *ipv6h, |
| struct sk_buff *skb)) |
| { |
| struct ip6_tnl *t; |
| const struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
| int err; |
| |
| rcu_read_lock(); |
| |
| if ((t = ip6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, |
| &ipv6h->daddr)) != NULL) { |
| struct pcpu_tstats *tstats; |
| |
| if (t->parms.proto != ipproto && t->parms.proto != 0) { |
| rcu_read_unlock(); |
| goto discard; |
| } |
| |
| if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
| rcu_read_unlock(); |
| goto discard; |
| } |
| |
| if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { |
| t->dev->stats.rx_dropped++; |
| rcu_read_unlock(); |
| goto discard; |
| } |
| skb->mac_header = skb->network_header; |
| skb_reset_network_header(skb); |
| skb->protocol = htons(protocol); |
| memset(skb->cb, 0, sizeof(struct inet6_skb_parm)); |
| |
| __skb_tunnel_rx(skb, t->dev, t->net); |
| |
| err = dscp_ecn_decapsulate(t, ipv6h, skb); |
| if (unlikely(err)) { |
| if (log_ecn_error) |
| net_info_ratelimited("non-ECT from %pI6 with dsfield=%#x\n", |
| &ipv6h->saddr, |
| ipv6_get_dsfield(ipv6h)); |
| if (err > 1) { |
| ++t->dev->stats.rx_frame_errors; |
| ++t->dev->stats.rx_errors; |
| rcu_read_unlock(); |
| goto discard; |
| } |
| } |
| |
| tstats = this_cpu_ptr(t->dev->tstats); |
| tstats->rx_packets++; |
| tstats->rx_bytes += skb->len; |
| |
| netif_rx(skb); |
| |
| rcu_read_unlock(); |
| return 0; |
| } |
| rcu_read_unlock(); |
| return 1; |
| |
| discard: |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| static int ip4ip6_rcv(struct sk_buff *skb) |
| { |
| return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP, |
| ip4ip6_dscp_ecn_decapsulate); |
| } |
| |
| static int ip6ip6_rcv(struct sk_buff *skb) |
| { |
| return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6, |
| ip6ip6_dscp_ecn_decapsulate); |
| } |
| |
| struct ipv6_tel_txoption { |
| struct ipv6_txoptions ops; |
| __u8 dst_opt[8]; |
| }; |
| |
| static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) |
| { |
| memset(opt, 0, sizeof(struct ipv6_tel_txoption)); |
| |
| opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; |
| opt->dst_opt[3] = 1; |
| opt->dst_opt[4] = encap_limit; |
| opt->dst_opt[5] = IPV6_TLV_PADN; |
| opt->dst_opt[6] = 1; |
| |
| opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; |
| opt->ops.opt_nflen = 8; |
| } |
| |
| /** |
| * ip6_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 bool |
| ip6_tnl_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) |
| { |
| return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); |
| } |
| |
| int ip6_tnl_xmit_ctl(struct ip6_tnl *t) |
| { |
| struct __ip6_tnl_parm *p = &t->parms; |
| int ret = 0; |
| struct net *net = t->net; |
| |
| if (p->flags & IP6_TNL_F_CAP_XMIT) { |
| struct net_device *ldev = NULL; |
| |
| rcu_read_lock(); |
| if (p->link) |
| ldev = dev_get_by_index_rcu(net, p->link); |
| |
| if (unlikely(!ipv6_chk_addr(net, &p->laddr, ldev, 0))) |
| pr_warn("%s xmit: Local address not yet configured!\n", |
| p->name); |
| else if (!ipv6_addr_is_multicast(&p->raddr) && |
| unlikely(ipv6_chk_addr(net, &p->raddr, NULL, 0))) |
| pr_warn("%s xmit: Routing loop! Remote address found on this node!\n", |
| p->name); |
| else |
| ret = 1; |
| rcu_read_unlock(); |
| } |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(ip6_tnl_xmit_ctl); |
| |
| /** |
| * ip6_tnl_xmit2 - encapsulate packet and send |
| * @skb: the outgoing socket buffer |
| * @dev: the outgoing tunnel device |
| * @dsfield: dscp code for outer header |
| * @fl: flow of tunneled packet |
| * @encap_limit: encapsulation limit |
| * @pmtu: Path MTU is stored if packet is too big |
| * |
| * Description: |
| * Build new header and do some sanity checks on the packet before sending |
| * it. |
| * |
| * Return: |
| * 0 on success |
| * -1 fail |
| * %-EMSGSIZE message too big. return mtu in this case. |
| **/ |
| |
| static int ip6_tnl_xmit2(struct sk_buff *skb, |
| struct net_device *dev, |
| __u8 dsfield, |
| struct flowi6 *fl6, |
| int encap_limit, |
| __u32 *pmtu) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct net *net = t->net; |
| struct net_device_stats *stats = &t->dev->stats; |
| struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
| struct ipv6_tel_txoption opt; |
| struct dst_entry *dst = NULL, *ndst = NULL; |
| struct net_device *tdev; |
| int mtu; |
| unsigned int max_headroom = sizeof(struct ipv6hdr); |
| u8 proto; |
| int err = -1; |
| |
| if (!fl6->flowi6_mark) |
| dst = ip6_tnl_dst_check(t); |
| if (!dst) { |
| ndst = ip6_route_output(net, NULL, fl6); |
| |
| if (ndst->error) |
| goto tx_err_link_failure; |
| ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(fl6), NULL, 0); |
| if (IS_ERR(ndst)) { |
| err = PTR_ERR(ndst); |
| ndst = NULL; |
| goto tx_err_link_failure; |
| } |
| dst = ndst; |
| } |
| |
| tdev = dst->dev; |
| |
| if (tdev == dev) { |
| stats->collisions++; |
| net_warn_ratelimited("%s: Local routing loop detected!\n", |
| t->parms.name); |
| goto tx_err_dst_release; |
| } |
| mtu = dst_mtu(dst) - sizeof (*ipv6h); |
| if (encap_limit >= 0) { |
| max_headroom += 8; |
| mtu -= 8; |
| } |
| if (mtu < IPV6_MIN_MTU) |
| mtu = IPV6_MIN_MTU; |
| if (skb_dst(skb)) |
| skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); |
| if (skb->len > mtu) { |
| *pmtu = mtu; |
| err = -EMSGSIZE; |
| goto tx_err_dst_release; |
| } |
| |
| skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); |
| |
| /* |
| * 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_shared(skb) || |
| (skb_cloned(skb) && !skb_clone_writable(skb, 0))) { |
| 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); |
| consume_skb(skb); |
| skb = new_skb; |
| } |
| if (fl6->flowi6_mark) { |
| skb_dst_set(skb, dst); |
| ndst = NULL; |
| } else { |
| skb_dst_set_noref(skb, dst); |
| } |
| skb->transport_header = skb->network_header; |
| |
| proto = fl6->flowi6_proto; |
| if (encap_limit >= 0) { |
| init_tel_txopt(&opt, encap_limit); |
| ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); |
| } |
| |
| if (likely(!skb->encapsulation)) { |
| skb_reset_inner_headers(skb); |
| skb->encapsulation = 1; |
| } |
| |
| skb_push(skb, sizeof(struct ipv6hdr)); |
| skb_reset_network_header(skb); |
| ipv6h = ipv6_hdr(skb); |
| ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), fl6->flowlabel); |
| ipv6h->hop_limit = t->parms.hop_limit; |
| ipv6h->nexthdr = proto; |
| ipv6h->saddr = fl6->saddr; |
| ipv6h->daddr = fl6->daddr; |
| ip6tunnel_xmit(skb, dev); |
| if (ndst) |
| ip6_tnl_dst_store(t, ndst); |
| return 0; |
| tx_err_link_failure: |
| stats->tx_carrier_errors++; |
| dst_link_failure(skb); |
| tx_err_dst_release: |
| dst_release(ndst); |
| return err; |
| } |
| |
| static inline int |
| ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| const struct iphdr *iph = ip_hdr(skb); |
| int encap_limit = -1; |
| struct flowi6 fl6; |
| __u8 dsfield; |
| __u32 mtu; |
| int err; |
| |
| if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) || |
| !ip6_tnl_xmit_ctl(t)) |
| return -1; |
| |
| if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) |
| encap_limit = t->parms.encap_limit; |
| |
| memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6)); |
| fl6.flowi6_proto = IPPROTO_IPIP; |
| |
| dsfield = ipv4_get_dsfield(iph); |
| |
| if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) |
| fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT) |
| & IPV6_TCLASS_MASK; |
| if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) |
| fl6.flowi6_mark = skb->mark; |
| |
| err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); |
| if (err != 0) { |
| /* XXX: send ICMP error even if DF is not set. */ |
| if (err == -EMSGSIZE) |
| icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, |
| htonl(mtu)); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static inline int |
| ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
| int encap_limit = -1; |
| __u16 offset; |
| struct flowi6 fl6; |
| __u8 dsfield; |
| __u32 mtu; |
| int err; |
| |
| if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || |
| !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h)) |
| return -1; |
| |
| offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb)); |
| if (offset > 0) { |
| struct ipv6_tlv_tnl_enc_lim *tel; |
| tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset]; |
| if (tel->encap_limit == 0) { |
| icmpv6_send(skb, ICMPV6_PARAMPROB, |
| ICMPV6_HDR_FIELD, offset + 2); |
| return -1; |
| } |
| encap_limit = tel->encap_limit - 1; |
| } else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) |
| encap_limit = t->parms.encap_limit; |
| |
| memcpy(&fl6, &t->fl.u.ip6, sizeof (fl6)); |
| fl6.flowi6_proto = IPPROTO_IPV6; |
| |
| dsfield = ipv6_get_dsfield(ipv6h); |
| if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) |
| fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK); |
| if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL) |
| fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_FLOWLABEL_MASK); |
| if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) |
| fl6.flowi6_mark = skb->mark; |
| |
| err = ip6_tnl_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); |
| if (err != 0) { |
| if (err == -EMSGSIZE) |
| icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static netdev_tx_t |
| ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct net_device_stats *stats = &t->dev->stats; |
| int ret; |
| |
| switch (skb->protocol) { |
| case htons(ETH_P_IP): |
| ret = ip4ip6_tnl_xmit(skb, dev); |
| break; |
| case htons(ETH_P_IPV6): |
| ret = ip6ip6_tnl_xmit(skb, dev); |
| break; |
| default: |
| goto tx_err; |
| } |
| |
| if (ret < 0) |
| goto tx_err; |
| |
| return NETDEV_TX_OK; |
| |
| tx_err: |
| stats->tx_errors++; |
| stats->tx_dropped++; |
| kfree_skb(skb); |
| return NETDEV_TX_OK; |
| } |
| |
| static void ip6_tnl_link_config(struct ip6_tnl *t) |
| { |
| struct net_device *dev = t->dev; |
| struct __ip6_tnl_parm *p = &t->parms; |
| struct flowi6 *fl6 = &t->fl.u.ip6; |
| |
| memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); |
| memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); |
| |
| /* Set up flowi template */ |
| fl6->saddr = p->laddr; |
| fl6->daddr = p->raddr; |
| fl6->flowi6_oif = p->link; |
| fl6->flowlabel = 0; |
| |
| if (!(p->flags&IP6_TNL_F_USE_ORIG_TCLASS)) |
| fl6->flowlabel |= IPV6_TCLASS_MASK & p->flowinfo; |
| if (!(p->flags&IP6_TNL_F_USE_ORIG_FLOWLABEL)) |
| fl6->flowlabel |= IPV6_FLOWLABEL_MASK & p->flowinfo; |
| |
| p->flags &= ~(IP6_TNL_F_CAP_XMIT|IP6_TNL_F_CAP_RCV|IP6_TNL_F_CAP_PER_PACKET); |
| p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr); |
| |
| 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) { |
| int strict = (ipv6_addr_type(&p->raddr) & |
| (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); |
| |
| struct rt6_info *rt = rt6_lookup(t->net, |
| &p->raddr, &p->laddr, |
| p->link, strict); |
| |
| if (rt == NULL) |
| return; |
| |
| if (rt->dst.dev) { |
| dev->hard_header_len = rt->dst.dev->hard_header_len + |
| sizeof (struct ipv6hdr); |
| |
| dev->mtu = rt->dst.dev->mtu - sizeof (struct ipv6hdr); |
| if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) |
| dev->mtu-=8; |
| |
| if (dev->mtu < IPV6_MIN_MTU) |
| dev->mtu = IPV6_MIN_MTU; |
| } |
| ip6_rt_put(rt); |
| } |
| } |
| |
| /** |
| * ip6_tnl_change - update the tunnel parameters |
| * @t: tunnel to be changed |
| * @p: tunnel configuration parameters |
| * |
| * Description: |
| * ip6_tnl_change() updates the tunnel parameters |
| **/ |
| |
| static int |
| ip6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) |
| { |
| t->parms.laddr = p->laddr; |
| 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; |
| t->parms.proto = p->proto; |
| ip6_tnl_dst_reset(t); |
| ip6_tnl_link_config(t); |
| return 0; |
| } |
| |
| static int ip6_tnl_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) |
| { |
| struct net *net = t->net; |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| int err; |
| |
| ip6_tnl_unlink(ip6n, t); |
| synchronize_net(); |
| err = ip6_tnl_change(t, p); |
| ip6_tnl_link(ip6n, t); |
| netdev_state_change(t->dev); |
| return err; |
| } |
| |
| static void |
| ip6_tnl_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm *u) |
| { |
| p->laddr = u->laddr; |
| p->raddr = u->raddr; |
| p->flags = u->flags; |
| p->hop_limit = u->hop_limit; |
| p->encap_limit = u->encap_limit; |
| p->flowinfo = u->flowinfo; |
| p->link = u->link; |
| p->proto = u->proto; |
| memcpy(p->name, u->name, sizeof(u->name)); |
| } |
| |
| static void |
| ip6_tnl_parm_to_user(struct ip6_tnl_parm *u, const struct __ip6_tnl_parm *p) |
| { |
| u->laddr = p->laddr; |
| u->raddr = p->raddr; |
| u->flags = p->flags; |
| u->hop_limit = p->hop_limit; |
| u->encap_limit = p->encap_limit; |
| u->flowinfo = p->flowinfo; |
| u->link = p->link; |
| u->proto = p->proto; |
| memcpy(u->name, p->name, sizeof(u->name)); |
| } |
| |
| /** |
| * ip6_tnl_ioctl - configure ipv6 tunnels from userspace |
| * @dev: virtual device associated with tunnel |
| * @ifr: parameters passed from userspace |
| * @cmd: command to be performed |
| * |
| * Description: |
| * ip6_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 |
| ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) |
| { |
| int err = 0; |
| struct ip6_tnl_parm p; |
| struct __ip6_tnl_parm p1; |
| struct ip6_tnl *t = NULL; |
| struct net *net = dev_net(dev); |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| |
| switch (cmd) { |
| case SIOCGETTUNNEL: |
| if (dev == ip6n->fb_tnl_dev) { |
| if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) { |
| err = -EFAULT; |
| break; |
| } |
| ip6_tnl_parm_from_user(&p1, &p); |
| t = ip6_tnl_locate(net, &p1, 0); |
| } else { |
| memset(&p, 0, sizeof(p)); |
| } |
| if (t == NULL) |
| t = netdev_priv(dev); |
| ip6_tnl_parm_to_user(&p, &t->parms); |
| if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) { |
| err = -EFAULT; |
| } |
| break; |
| case SIOCADDTUNNEL: |
| case SIOCCHGTUNNEL: |
| err = -EPERM; |
| if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
| break; |
| err = -EFAULT; |
| if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) |
| break; |
| err = -EINVAL; |
| if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP && |
| p.proto != 0) |
| break; |
| ip6_tnl_parm_from_user(&p1, &p); |
| t = ip6_tnl_locate(net, &p1, cmd == SIOCADDTUNNEL); |
| if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { |
| if (t != NULL) { |
| if (t->dev != dev) { |
| err = -EEXIST; |
| break; |
| } |
| } else |
| t = netdev_priv(dev); |
| |
| err = ip6_tnl_update(t, &p1); |
| } |
| if (t) { |
| err = 0; |
| ip6_tnl_parm_to_user(&p, &t->parms); |
| if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) |
| err = -EFAULT; |
| |
| } else |
| err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT); |
| break; |
| case SIOCDELTUNNEL: |
| err = -EPERM; |
| if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
| break; |
| |
| if (dev == ip6n->fb_tnl_dev) { |
| err = -EFAULT; |
| if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) |
| break; |
| err = -ENOENT; |
| ip6_tnl_parm_from_user(&p1, &p); |
| t = ip6_tnl_locate(net, &p1, 0); |
| if (t == NULL) |
| break; |
| err = -EPERM; |
| if (t->dev == ip6n->fb_tnl_dev) |
| break; |
| dev = t->dev; |
| } |
| err = 0; |
| unregister_netdevice(dev); |
| break; |
| default: |
| err = -EINVAL; |
| } |
| return err; |
| } |
| |
| /** |
| * ip6_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 |
| ip6_tnl_change_mtu(struct net_device *dev, int new_mtu) |
| { |
| struct ip6_tnl *tnl = netdev_priv(dev); |
| |
| if (tnl->parms.proto == IPPROTO_IPIP) { |
| if (new_mtu < 68) |
| return -EINVAL; |
| } else { |
| if (new_mtu < IPV6_MIN_MTU) |
| return -EINVAL; |
| } |
| if (new_mtu > 0xFFF8 - dev->hard_header_len) |
| return -EINVAL; |
| dev->mtu = new_mtu; |
| return 0; |
| } |
| |
| |
| static const struct net_device_ops ip6_tnl_netdev_ops = { |
| .ndo_uninit = ip6_tnl_dev_uninit, |
| .ndo_start_xmit = ip6_tnl_xmit, |
| .ndo_do_ioctl = ip6_tnl_ioctl, |
| .ndo_change_mtu = ip6_tnl_change_mtu, |
| .ndo_get_stats = ip6_get_stats, |
| }; |
| |
| |
| /** |
| * ip6_tnl_dev_setup - setup virtual tunnel device |
| * @dev: virtual device associated with tunnel |
| * |
| * Description: |
| * Initialize function pointers and device parameters |
| **/ |
| |
| static void ip6_tnl_dev_setup(struct net_device *dev) |
| { |
| struct ip6_tnl *t; |
| |
| dev->netdev_ops = &ip6_tnl_netdev_ops; |
| dev->destructor = ip6_dev_free; |
| |
| dev->type = ARPHRD_TUNNEL6; |
| dev->hard_header_len = LL_MAX_HEADER + sizeof (struct ipv6hdr); |
| dev->mtu = ETH_DATA_LEN - sizeof (struct ipv6hdr); |
| t = netdev_priv(dev); |
| if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) |
| dev->mtu-=8; |
| dev->flags |= IFF_NOARP; |
| dev->addr_len = sizeof(struct in6_addr); |
| dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; |
| /* This perm addr will be used as interface identifier by IPv6 */ |
| dev->addr_assign_type = NET_ADDR_RANDOM; |
| eth_random_addr(dev->perm_addr); |
| } |
| |
| |
| /** |
| * ip6_tnl_dev_init_gen - general initializer for all tunnel devices |
| * @dev: virtual device associated with tunnel |
| **/ |
| |
| static inline int |
| ip6_tnl_dev_init_gen(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| int i; |
| |
| t->dev = dev; |
| t->net = dev_net(dev); |
| dev->tstats = alloc_percpu(struct pcpu_tstats); |
| if (!dev->tstats) |
| return -ENOMEM; |
| |
| for_each_possible_cpu(i) { |
| struct pcpu_tstats *ip6_tnl_stats; |
| ip6_tnl_stats = per_cpu_ptr(dev->tstats, i); |
| u64_stats_init(&ip6_tnl_stats->syncp); |
| } |
| return 0; |
| } |
| |
| /** |
| * ip6_tnl_dev_init - initializer for all non fallback tunnel devices |
| * @dev: virtual device associated with tunnel |
| **/ |
| |
| static int ip6_tnl_dev_init(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| int err = ip6_tnl_dev_init_gen(dev); |
| |
| if (err) |
| return err; |
| ip6_tnl_link_config(t); |
| return 0; |
| } |
| |
| /** |
| * ip6_fb_tnl_dev_init - initializer for fallback tunnel device |
| * @dev: fallback device |
| * |
| * Return: 0 |
| **/ |
| |
| static int __net_init ip6_fb_tnl_dev_init(struct net_device *dev) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct net *net = dev_net(dev); |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| int err = ip6_tnl_dev_init_gen(dev); |
| |
| if (err) |
| return err; |
| |
| t->parms.proto = IPPROTO_IPV6; |
| dev_hold(dev); |
| |
| ip6_tnl_link_config(t); |
| |
| rcu_assign_pointer(ip6n->tnls_wc[0], t); |
| return 0; |
| } |
| |
| static int ip6_tnl_validate(struct nlattr *tb[], struct nlattr *data[]) |
| { |
| u8 proto; |
| |
| if (!data) |
| return 0; |
| |
| proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); |
| if (proto != IPPROTO_IPV6 && |
| proto != IPPROTO_IPIP && |
| proto != 0) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| static void ip6_tnl_netlink_parms(struct nlattr *data[], |
| struct __ip6_tnl_parm *parms) |
| { |
| memset(parms, 0, sizeof(*parms)); |
| |
| if (!data) |
| return; |
| |
| if (data[IFLA_IPTUN_LINK]) |
| parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]); |
| |
| if (data[IFLA_IPTUN_LOCAL]) |
| nla_memcpy(&parms->laddr, data[IFLA_IPTUN_LOCAL], |
| sizeof(struct in6_addr)); |
| |
| if (data[IFLA_IPTUN_REMOTE]) |
| nla_memcpy(&parms->raddr, data[IFLA_IPTUN_REMOTE], |
| sizeof(struct in6_addr)); |
| |
| if (data[IFLA_IPTUN_TTL]) |
| parms->hop_limit = nla_get_u8(data[IFLA_IPTUN_TTL]); |
| |
| if (data[IFLA_IPTUN_ENCAP_LIMIT]) |
| parms->encap_limit = nla_get_u8(data[IFLA_IPTUN_ENCAP_LIMIT]); |
| |
| if (data[IFLA_IPTUN_FLOWINFO]) |
| parms->flowinfo = nla_get_be32(data[IFLA_IPTUN_FLOWINFO]); |
| |
| if (data[IFLA_IPTUN_FLAGS]) |
| parms->flags = nla_get_u32(data[IFLA_IPTUN_FLAGS]); |
| |
| if (data[IFLA_IPTUN_PROTO]) |
| parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]); |
| } |
| |
| static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev, |
| struct nlattr *tb[], struct nlattr *data[]) |
| { |
| struct net *net = dev_net(dev); |
| struct ip6_tnl *nt; |
| |
| nt = netdev_priv(dev); |
| ip6_tnl_netlink_parms(data, &nt->parms); |
| |
| if (ip6_tnl_locate(net, &nt->parms, 0)) |
| return -EEXIST; |
| |
| return ip6_tnl_create2(dev); |
| } |
| |
| static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[], |
| struct nlattr *data[]) |
| { |
| struct ip6_tnl *t = netdev_priv(dev); |
| struct __ip6_tnl_parm p; |
| struct net *net = t->net; |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| |
| if (dev == ip6n->fb_tnl_dev) |
| return -EINVAL; |
| |
| ip6_tnl_netlink_parms(data, &p); |
| |
| t = ip6_tnl_locate(net, &p, 0); |
| |
| if (t) { |
| if (t->dev != dev) |
| return -EEXIST; |
| } else |
| t = netdev_priv(dev); |
| |
| return ip6_tnl_update(t, &p); |
| } |
| |
| static size_t ip6_tnl_get_size(const struct net_device *dev) |
| { |
| return |
| /* IFLA_IPTUN_LINK */ |
| nla_total_size(4) + |
| /* IFLA_IPTUN_LOCAL */ |
| nla_total_size(sizeof(struct in6_addr)) + |
| /* IFLA_IPTUN_REMOTE */ |
| nla_total_size(sizeof(struct in6_addr)) + |
| /* IFLA_IPTUN_TTL */ |
| nla_total_size(1) + |
| /* IFLA_IPTUN_ENCAP_LIMIT */ |
| nla_total_size(1) + |
| /* IFLA_IPTUN_FLOWINFO */ |
| nla_total_size(4) + |
| /* IFLA_IPTUN_FLAGS */ |
| nla_total_size(4) + |
| /* IFLA_IPTUN_PROTO */ |
| nla_total_size(1) + |
| 0; |
| } |
| |
| static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev) |
| { |
| struct ip6_tnl *tunnel = netdev_priv(dev); |
| struct __ip6_tnl_parm *parm = &tunnel->parms; |
| |
| if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) || |
| nla_put(skb, IFLA_IPTUN_LOCAL, sizeof(struct in6_addr), |
| &parm->laddr) || |
| nla_put(skb, IFLA_IPTUN_REMOTE, sizeof(struct in6_addr), |
| &parm->raddr) || |
| nla_put_u8(skb, IFLA_IPTUN_TTL, parm->hop_limit) || |
| nla_put_u8(skb, IFLA_IPTUN_ENCAP_LIMIT, parm->encap_limit) || |
| nla_put_be32(skb, IFLA_IPTUN_FLOWINFO, parm->flowinfo) || |
| nla_put_u32(skb, IFLA_IPTUN_FLAGS, parm->flags) || |
| nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto)) |
| goto nla_put_failure; |
| return 0; |
| |
| nla_put_failure: |
| return -EMSGSIZE; |
| } |
| |
| static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = { |
| [IFLA_IPTUN_LINK] = { .type = NLA_U32 }, |
| [IFLA_IPTUN_LOCAL] = { .len = sizeof(struct in6_addr) }, |
| [IFLA_IPTUN_REMOTE] = { .len = sizeof(struct in6_addr) }, |
| [IFLA_IPTUN_TTL] = { .type = NLA_U8 }, |
| [IFLA_IPTUN_ENCAP_LIMIT] = { .type = NLA_U8 }, |
| [IFLA_IPTUN_FLOWINFO] = { .type = NLA_U32 }, |
| [IFLA_IPTUN_FLAGS] = { .type = NLA_U32 }, |
| [IFLA_IPTUN_PROTO] = { .type = NLA_U8 }, |
| }; |
| |
| static struct rtnl_link_ops ip6_link_ops __read_mostly = { |
| .kind = "ip6tnl", |
| .maxtype = IFLA_IPTUN_MAX, |
| .policy = ip6_tnl_policy, |
| .priv_size = sizeof(struct ip6_tnl), |
| .setup = ip6_tnl_dev_setup, |
| .validate = ip6_tnl_validate, |
| .newlink = ip6_tnl_newlink, |
| .changelink = ip6_tnl_changelink, |
| .get_size = ip6_tnl_get_size, |
| .fill_info = ip6_tnl_fill_info, |
| }; |
| |
| static struct xfrm6_tunnel ip4ip6_handler __read_mostly = { |
| .handler = ip4ip6_rcv, |
| .err_handler = ip4ip6_err, |
| .priority = 1, |
| }; |
| |
| static struct xfrm6_tunnel ip6ip6_handler __read_mostly = { |
| .handler = ip6ip6_rcv, |
| .err_handler = ip6ip6_err, |
| .priority = 1, |
| }; |
| |
| static void __net_exit ip6_tnl_destroy_tunnels(struct ip6_tnl_net *ip6n) |
| { |
| struct net *net = dev_net(ip6n->fb_tnl_dev); |
| struct net_device *dev, *aux; |
| int h; |
| struct ip6_tnl *t; |
| LIST_HEAD(list); |
| |
| for_each_netdev_safe(net, dev, aux) |
| if (dev->rtnl_link_ops == &ip6_link_ops) |
| unregister_netdevice_queue(dev, &list); |
| |
| for (h = 0; h < HASH_SIZE; h++) { |
| t = rtnl_dereference(ip6n->tnls_r_l[h]); |
| while (t != NULL) { |
| /* If dev is in the same netns, it has already |
| * been added to the list by the previous loop. |
| */ |
| if (!net_eq(dev_net(t->dev), net)) |
| unregister_netdevice_queue(t->dev, &list); |
| t = rtnl_dereference(t->next); |
| } |
| } |
| |
| unregister_netdevice_many(&list); |
| } |
| |
| static int __net_init ip6_tnl_init_net(struct net *net) |
| { |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| struct ip6_tnl *t = NULL; |
| int err; |
| |
| ip6n->tnls[0] = ip6n->tnls_wc; |
| ip6n->tnls[1] = ip6n->tnls_r_l; |
| |
| err = -ENOMEM; |
| ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6tnl0", |
| ip6_tnl_dev_setup); |
| |
| if (!ip6n->fb_tnl_dev) |
| goto err_alloc_dev; |
| dev_net_set(ip6n->fb_tnl_dev, net); |
| ip6n->fb_tnl_dev->rtnl_link_ops = &ip6_link_ops; |
| /* FB netdevice is special: we have one, and only one per netns. |
| * Allowing to move it to another netns is clearly unsafe. |
| */ |
| ip6n->fb_tnl_dev->features |= NETIF_F_NETNS_LOCAL; |
| |
| err = ip6_fb_tnl_dev_init(ip6n->fb_tnl_dev); |
| if (err < 0) |
| goto err_register; |
| |
| err = register_netdev(ip6n->fb_tnl_dev); |
| if (err < 0) |
| goto err_register; |
| |
| t = netdev_priv(ip6n->fb_tnl_dev); |
| |
| strcpy(t->parms.name, ip6n->fb_tnl_dev->name); |
| return 0; |
| |
| err_register: |
| ip6_dev_free(ip6n->fb_tnl_dev); |
| err_alloc_dev: |
| return err; |
| } |
| |
| static void __net_exit ip6_tnl_exit_net(struct net *net) |
| { |
| struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id); |
| |
| rtnl_lock(); |
| ip6_tnl_destroy_tunnels(ip6n); |
| rtnl_unlock(); |
| } |
| |
| static struct pernet_operations ip6_tnl_net_ops = { |
| .init = ip6_tnl_init_net, |
| .exit = ip6_tnl_exit_net, |
| .id = &ip6_tnl_net_id, |
| .size = sizeof(struct ip6_tnl_net), |
| }; |
| |
| /** |
| * ip6_tunnel_init - register protocol and reserve needed resources |
| * |
| * Return: 0 on success |
| **/ |
| |
| static int __init ip6_tunnel_init(void) |
| { |
| int err; |
| |
| err = register_pernet_device(&ip6_tnl_net_ops); |
| if (err < 0) |
| goto out_pernet; |
| |
| err = xfrm6_tunnel_register(&ip4ip6_handler, AF_INET); |
| if (err < 0) { |
| pr_err("%s: can't register ip4ip6\n", __func__); |
| goto out_ip4ip6; |
| } |
| |
| err = xfrm6_tunnel_register(&ip6ip6_handler, AF_INET6); |
| if (err < 0) { |
| pr_err("%s: can't register ip6ip6\n", __func__); |
| goto out_ip6ip6; |
| } |
| err = rtnl_link_register(&ip6_link_ops); |
| if (err < 0) |
| goto rtnl_link_failed; |
| |
| return 0; |
| |
| rtnl_link_failed: |
| xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6); |
| out_ip6ip6: |
| xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET); |
| out_ip4ip6: |
| unregister_pernet_device(&ip6_tnl_net_ops); |
| out_pernet: |
| return err; |
| } |
| |
| /** |
| * ip6_tunnel_cleanup - free resources and unregister protocol |
| **/ |
| |
| static void __exit ip6_tunnel_cleanup(void) |
| { |
| rtnl_link_unregister(&ip6_link_ops); |
| if (xfrm6_tunnel_deregister(&ip4ip6_handler, AF_INET)) |
| pr_info("%s: can't deregister ip4ip6\n", __func__); |
| |
| if (xfrm6_tunnel_deregister(&ip6ip6_handler, AF_INET6)) |
| pr_info("%s: can't deregister ip6ip6\n", __func__); |
| |
| unregister_pernet_device(&ip6_tnl_net_ops); |
| } |
| |
| module_init(ip6_tunnel_init); |
| module_exit(ip6_tunnel_cleanup); |