diff options
Diffstat (limited to 'net/ipv6/ip6_vti.c')
| -rw-r--r-- | net/ipv6/ip6_vti.c | 1194 |
1 files changed, 1194 insertions, 0 deletions
diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c new file mode 100644 index 000000000..0224c032d --- /dev/null +++ b/net/ipv6/ip6_vti.c @@ -0,0 +1,1194 @@ +/* + * IPv6 virtual tunneling interface + * + * Copyright (C) 2013 secunet Security Networks AG + * + * Author: + * Steffen Klassert <steffen.klassert@secunet.com> + * + * Based on: + * net/ipv6/ip6_tunnel.c + * + * 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/icmp.h> +#include <linux/if.h> +#include <linux/in.h> +#include <linux/ip.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/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/net_namespace.h> +#include <net/netns/generic.h> + +#define HASH_SIZE_SHIFT 5 +#define HASH_SIZE (1 << HASH_SIZE_SHIFT) + +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 vti6_dev_init(struct net_device *dev); +static void vti6_dev_setup(struct net_device *dev); +static struct rtnl_link_ops vti6_link_ops __read_mostly; + +static int vti6_net_id __read_mostly; +struct vti6_net { + /* the vti6 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]; +}; + +#define for_each_vti6_tunnel_rcu(start) \ + for (t = rcu_dereference(start); t; t = rcu_dereference(t->next)) + +/** + * vti6_tnl_lookup - fetch tunnel matching the end-point addresses + * @net: network namespace + * @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 * +vti6_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 vti6_net *ip6n = net_generic(net, vti6_net_id); + struct in6_addr any; + + for_each_vti6_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; + } + + memset(&any, 0, sizeof(any)); + hash = HASH(&any, local); + for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { + if (ipv6_addr_equal(local, &t->parms.laddr) && + (t->dev->flags & IFF_UP)) + return t; + } + + hash = HASH(remote, &any); + for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) { + if (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; +} + +/** + * vti6_tnl_bucket - get head of list matching given tunnel parameters + * @p: parameters containing tunnel end-points + * + * Description: + * vti6_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 ** +vti6_tnl_bucket(struct vti6_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]; +} + +static void +vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t) +{ + struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms); + + rcu_assign_pointer(t->next , rtnl_dereference(*tp)); + rcu_assign_pointer(*tp, t); +} + +static void +vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t) +{ + struct ip6_tnl __rcu **tp; + struct ip6_tnl *iter; + + for (tp = vti6_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 vti6_dev_free(struct net_device *dev) +{ + free_percpu(dev->tstats); + free_netdev(dev); +} + +static int vti6_tnl_create2(struct net_device *dev) +{ + struct ip6_tnl *t = netdev_priv(dev); + struct net *net = dev_net(dev); + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + int err; + + err = register_netdevice(dev); + if (err < 0) + goto out; + + strcpy(t->parms.name, dev->name); + dev->rtnl_link_ops = &vti6_link_ops; + + dev_hold(dev); + vti6_tnl_link(ip6n, t); + + return 0; + +out: + return err; +} + +static struct ip6_tnl *vti6_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, "ip6_vti%%d"); + + dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup); + if (!dev) + goto failed; + + dev_net_set(dev, net); + + t = netdev_priv(dev); + t->parms = *p; + t->net = dev_net(dev); + + err = vti6_tnl_create2(dev); + if (err < 0) + goto failed_free; + + return t; + +failed_free: + vti6_dev_free(dev); +failed: + return NULL; +} + +/** + * vti6_locate - find or create tunnel matching given parameters + * @net: network namespace + * @p: tunnel parameters + * @create: != 0 if allowed to create new tunnel if no match found + * + * Description: + * vti6_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 *vti6_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 vti6_net *ip6n = net_generic(net, vti6_net_id); + + for (tp = vti6_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)) { + if (create) + return NULL; + + return t; + } + } + if (!create) + return NULL; + return vti6_tnl_create(net, p); +} + +/** + * vti6_dev_uninit - tunnel device uninitializer + * @dev: the device to be destroyed + * + * Description: + * vti6_dev_uninit() removes tunnel from its list + **/ +static void vti6_dev_uninit(struct net_device *dev) +{ + struct ip6_tnl *t = netdev_priv(dev); + struct vti6_net *ip6n = net_generic(t->net, vti6_net_id); + + if (dev == ip6n->fb_tnl_dev) + RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL); + else + vti6_tnl_unlink(ip6n, t); + dev_put(dev); +} + +static int vti6_rcv(struct sk_buff *skb) +{ + struct ip6_tnl *t; + const struct ipv6hdr *ipv6h = ipv6_hdr(skb); + + rcu_read_lock(); + t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr); + if (t) { + if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) { + rcu_read_unlock(); + goto discard; + } + + if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { + rcu_read_unlock(); + return 0; + } + + if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { + t->dev->stats.rx_dropped++; + rcu_read_unlock(); + goto discard; + } + + XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; + + rcu_read_unlock(); + + return xfrm6_rcv(skb); + } + rcu_read_unlock(); + return -EINVAL; +discard: + kfree_skb(skb); + return 0; +} + +static int vti6_rcv_cb(struct sk_buff *skb, int err) +{ + unsigned short family; + struct net_device *dev; + struct pcpu_sw_netstats *tstats; + struct xfrm_state *x; + struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6; + u32 orig_mark = skb->mark; + int ret; + + if (!t) + return 1; + + dev = t->dev; + + if (err) { + dev->stats.rx_errors++; + dev->stats.rx_dropped++; + + return 0; + } + + x = xfrm_input_state(skb); + family = x->inner_mode->afinfo->family; + + skb->mark = be32_to_cpu(t->parms.i_key); + ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family); + skb->mark = orig_mark; + + if (!ret) + return -EPERM; + + skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev))); + skb->dev = dev; + + tstats = this_cpu_ptr(dev->tstats); + u64_stats_update_begin(&tstats->syncp); + tstats->rx_packets++; + tstats->rx_bytes += skb->len; + u64_stats_update_end(&tstats->syncp); + + return 0; +} + +/** + * vti6_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 +vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr) +{ + return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr); +} + +static bool vti6_state_check(const struct xfrm_state *x, + const struct in6_addr *dst, + const struct in6_addr *src) +{ + xfrm_address_t *daddr = (xfrm_address_t *)dst; + xfrm_address_t *saddr = (xfrm_address_t *)src; + + /* if there is no transform then this tunnel is not functional. + * Or if the xfrm is not mode tunnel. + */ + if (!x || x->props.mode != XFRM_MODE_TUNNEL || + x->props.family != AF_INET6) + return false; + + if (ipv6_addr_any(dst)) + return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6); + + if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6)) + return false; + + return true; +} + +/** + * vti6_xmit - send a packet + * @skb: the outgoing socket buffer + * @dev: the outgoing tunnel device + * @fl: the flow informations for the xfrm_lookup + **/ +static int +vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) +{ + struct ip6_tnl *t = netdev_priv(dev); + struct net_device_stats *stats = &t->dev->stats; + struct dst_entry *dst = skb_dst(skb); + struct net_device *tdev; + struct xfrm_state *x; + int err = -1; + int mtu; + + if (!dst) + goto tx_err_link_failure; + + dst_hold(dst); + dst = xfrm_lookup(t->net, dst, fl, NULL, 0); + if (IS_ERR(dst)) { + err = PTR_ERR(dst); + dst = NULL; + goto tx_err_link_failure; + } + + x = dst->xfrm; + if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr)) + goto tx_err_link_failure; + + if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr, + (const struct in6_addr *)&x->id.daddr)) + goto tx_err_link_failure; + + 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; + } + + skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); + skb_dst_set(skb, dst); + skb->dev = skb_dst(skb)->dev; + + mtu = dst_mtu(dst); + if (!skb->ignore_df && skb->len > mtu) { + skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu); + + if (skb->protocol == htons(ETH_P_IPV6)) + icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); + else + icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, + htonl(mtu)); + + return -EMSGSIZE; + } + + err = dst_output(skb); + if (net_xmit_eval(err) == 0) { + struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats); + + u64_stats_update_begin(&tstats->syncp); + tstats->tx_bytes += skb->len; + tstats->tx_packets++; + u64_stats_update_end(&tstats->syncp); + } else { + stats->tx_errors++; + stats->tx_aborted_errors++; + } + + return 0; +tx_err_link_failure: + stats->tx_carrier_errors++; + dst_link_failure(skb); +tx_err_dst_release: + dst_release(dst); + return err; +} + +static netdev_tx_t +vti6_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; + struct ipv6hdr *ipv6h; + struct flowi fl; + int ret; + + memset(&fl, 0, sizeof(fl)); + + switch (skb->protocol) { + case htons(ETH_P_IPV6): + ipv6h = ipv6_hdr(skb); + + if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || + vti6_addr_conflict(t, ipv6h)) + goto tx_err; + + xfrm_decode_session(skb, &fl, AF_INET6); + memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); + break; + case htons(ETH_P_IP): + xfrm_decode_session(skb, &fl, AF_INET); + memset(IPCB(skb), 0, sizeof(*IPCB(skb))); + break; + default: + goto tx_err; + } + + /* override mark with tunnel output key */ + fl.flowi_mark = be32_to_cpu(t->parms.o_key); + + ret = vti6_xmit(skb, dev, &fl); + 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 int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, + u8 type, u8 code, int offset, __be32 info) +{ + __be32 spi; + __u32 mark; + struct xfrm_state *x; + struct ip6_tnl *t; + struct ip_esp_hdr *esph; + struct ip_auth_hdr *ah; + struct ip_comp_hdr *ipch; + struct net *net = dev_net(skb->dev); + const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; + int protocol = iph->nexthdr; + + t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr); + if (!t) + return -1; + + mark = be32_to_cpu(t->parms.o_key); + + switch (protocol) { + case IPPROTO_ESP: + esph = (struct ip_esp_hdr *)(skb->data + offset); + spi = esph->spi; + break; + case IPPROTO_AH: + ah = (struct ip_auth_hdr *)(skb->data + offset); + spi = ah->spi; + break; + case IPPROTO_COMP: + ipch = (struct ip_comp_hdr *)(skb->data + offset); + spi = htonl(ntohs(ipch->cpi)); + break; + default: + return 0; + } + + if (type != ICMPV6_PKT_TOOBIG && + type != NDISC_REDIRECT) + return 0; + + x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr, + spi, protocol, AF_INET6); + if (!x) + return 0; + + if (type == NDISC_REDIRECT) + ip6_redirect(skb, net, skb->dev->ifindex, 0); + else + ip6_update_pmtu(skb, net, info, 0, 0); + xfrm_state_put(x); + + return 0; +} + +static void vti6_link_config(struct ip6_tnl *t) +{ + struct net_device *dev = t->dev; + struct __ip6_tnl_parm *p = &t->parms; + + memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); + memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); + + 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; +} + +/** + * vti6_tnl_change - update the tunnel parameters + * @t: tunnel to be changed + * @p: tunnel configuration parameters + * + * Description: + * vti6_tnl_change() updates the tunnel parameters + **/ +static int +vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p) +{ + t->parms.laddr = p->laddr; + t->parms.raddr = p->raddr; + t->parms.link = p->link; + t->parms.i_key = p->i_key; + t->parms.o_key = p->o_key; + t->parms.proto = p->proto; + ip6_tnl_dst_reset(t); + vti6_link_config(t); + return 0; +} + +static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p) +{ + struct net *net = dev_net(t->dev); + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + int err; + + vti6_tnl_unlink(ip6n, t); + synchronize_net(); + err = vti6_tnl_change(t, p); + vti6_tnl_link(ip6n, t); + netdev_state_change(t->dev); + return err; +} + +static void +vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u) +{ + p->laddr = u->laddr; + p->raddr = u->raddr; + p->link = u->link; + p->i_key = u->i_key; + p->o_key = u->o_key; + p->proto = u->proto; + + memcpy(p->name, u->name, sizeof(u->name)); +} + +static void +vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p) +{ + u->laddr = p->laddr; + u->raddr = p->raddr; + u->link = p->link; + u->i_key = p->i_key; + u->o_key = p->o_key; + u->proto = p->proto; + + memcpy(u->name, p->name, sizeof(u->name)); +} + +/** + * vti6_tnl_ioctl - configure vti6 tunnels from userspace + * @dev: virtual device associated with tunnel + * @ifr: parameters passed from userspace + * @cmd: command to be performed + * + * Description: + * vti6_ioctl() is used for managing vti6 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 "ip6_vti0", 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 +vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) +{ + int err = 0; + struct ip6_tnl_parm2 p; + struct __ip6_tnl_parm p1; + struct ip6_tnl *t = NULL; + struct net *net = dev_net(dev); + struct vti6_net *ip6n = net_generic(net, vti6_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; + } + vti6_parm_from_user(&p1, &p); + t = vti6_locate(net, &p1, 0); + } else { + memset(&p, 0, sizeof(p)); + } + if (!t) + t = netdev_priv(dev); + vti6_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 != 0) + break; + vti6_parm_from_user(&p1, &p); + t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL); + if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) { + if (t) { + if (t->dev != dev) { + err = -EEXIST; + break; + } + } else + t = netdev_priv(dev); + + err = vti6_update(t, &p1); + } + if (t) { + err = 0; + vti6_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; + vti6_parm_from_user(&p1, &p); + t = vti6_locate(net, &p1, 0); + if (!t) + 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; +} + +/** + * vti6_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 vti6_change_mtu(struct net_device *dev, int new_mtu) +{ + if (new_mtu < IPV6_MIN_MTU) + return -EINVAL; + + dev->mtu = new_mtu; + return 0; +} + +static const struct net_device_ops vti6_netdev_ops = { + .ndo_init = vti6_dev_init, + .ndo_uninit = vti6_dev_uninit, + .ndo_start_xmit = vti6_tnl_xmit, + .ndo_do_ioctl = vti6_ioctl, + .ndo_change_mtu = vti6_change_mtu, + .ndo_get_stats64 = ip_tunnel_get_stats64, + .ndo_get_iflink = ip6_tnl_get_iflink, +}; + +/** + * vti6_dev_setup - setup virtual tunnel device + * @dev: virtual device associated with tunnel + * + * Description: + * Initialize function pointers and device parameters + **/ +static void vti6_dev_setup(struct net_device *dev) +{ + dev->netdev_ops = &vti6_netdev_ops; + dev->destructor = vti6_dev_free; + + dev->type = ARPHRD_TUNNEL6; + dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr); + dev->mtu = ETH_DATA_LEN; + dev->flags |= IFF_NOARP; + dev->addr_len = sizeof(struct in6_addr); + netif_keep_dst(dev); +} + +/** + * vti6_dev_init_gen - general initializer for all tunnel devices + * @dev: virtual device associated with tunnel + **/ +static inline int vti6_dev_init_gen(struct net_device *dev) +{ + struct ip6_tnl *t = netdev_priv(dev); + + t->dev = dev; + t->net = dev_net(dev); + dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); + if (!dev->tstats) + return -ENOMEM; + return 0; +} + +/** + * vti6_dev_init - initializer for all non fallback tunnel devices + * @dev: virtual device associated with tunnel + **/ +static int vti6_dev_init(struct net_device *dev) +{ + struct ip6_tnl *t = netdev_priv(dev); + int err = vti6_dev_init_gen(dev); + + if (err) + return err; + vti6_link_config(t); + return 0; +} + +/** + * vti6_fb_tnl_dev_init - initializer for fallback tunnel device + * @dev: fallback device + * + * Return: 0 + **/ +static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev) +{ + struct ip6_tnl *t = netdev_priv(dev); + struct net *net = dev_net(dev); + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + + t->parms.proto = IPPROTO_IPV6; + dev_hold(dev); + + rcu_assign_pointer(ip6n->tnls_wc[0], t); + return 0; +} + +static int vti6_validate(struct nlattr *tb[], struct nlattr *data[]) +{ + return 0; +} + +static void vti6_netlink_parms(struct nlattr *data[], + struct __ip6_tnl_parm *parms) +{ + memset(parms, 0, sizeof(*parms)); + + if (!data) + return; + + if (data[IFLA_VTI_LINK]) + parms->link = nla_get_u32(data[IFLA_VTI_LINK]); + + if (data[IFLA_VTI_LOCAL]) + parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]); + + if (data[IFLA_VTI_REMOTE]) + parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]); + + if (data[IFLA_VTI_IKEY]) + parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); + + if (data[IFLA_VTI_OKEY]) + parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); +} + +static int vti6_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); + vti6_netlink_parms(data, &nt->parms); + + nt->parms.proto = IPPROTO_IPV6; + + if (vti6_locate(net, &nt->parms, 0)) + return -EEXIST; + + return vti6_tnl_create2(dev); +} + +static void vti6_dellink(struct net_device *dev, struct list_head *head) +{ + struct net *net = dev_net(dev); + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + + if (dev != ip6n->fb_tnl_dev) + unregister_netdevice_queue(dev, head); +} + +static int vti6_changelink(struct net_device *dev, struct nlattr *tb[], + struct nlattr *data[]) +{ + struct ip6_tnl *t; + struct __ip6_tnl_parm p; + struct net *net = dev_net(dev); + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + + if (dev == ip6n->fb_tnl_dev) + return -EINVAL; + + vti6_netlink_parms(data, &p); + + t = vti6_locate(net, &p, 0); + + if (t) { + if (t->dev != dev) + return -EEXIST; + } else + t = netdev_priv(dev); + + return vti6_update(t, &p); +} + +static size_t vti6_get_size(const struct net_device *dev) +{ + return + /* IFLA_VTI_LINK */ + nla_total_size(4) + + /* IFLA_VTI_LOCAL */ + nla_total_size(sizeof(struct in6_addr)) + + /* IFLA_VTI_REMOTE */ + nla_total_size(sizeof(struct in6_addr)) + + /* IFLA_VTI_IKEY */ + nla_total_size(4) + + /* IFLA_VTI_OKEY */ + nla_total_size(4) + + 0; +} + +static int vti6_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_VTI_LINK, parm->link) || + nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) || + nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) || + nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) || + nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key)) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = { + [IFLA_VTI_LINK] = { .type = NLA_U32 }, + [IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) }, + [IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) }, + [IFLA_VTI_IKEY] = { .type = NLA_U32 }, + [IFLA_VTI_OKEY] = { .type = NLA_U32 }, +}; + +static struct rtnl_link_ops vti6_link_ops __read_mostly = { + .kind = "vti6", + .maxtype = IFLA_VTI_MAX, + .policy = vti6_policy, + .priv_size = sizeof(struct ip6_tnl), + .setup = vti6_dev_setup, + .validate = vti6_validate, + .newlink = vti6_newlink, + .dellink = vti6_dellink, + .changelink = vti6_changelink, + .get_size = vti6_get_size, + .fill_info = vti6_fill_info, + .get_link_net = ip6_tnl_get_link_net, +}; + +static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n) +{ + int h; + struct ip6_tnl *t; + LIST_HEAD(list); + + for (h = 0; h < HASH_SIZE; h++) { + t = rtnl_dereference(ip6n->tnls_r_l[h]); + while (t) { + unregister_netdevice_queue(t->dev, &list); + t = rtnl_dereference(t->next); + } + } + + t = rtnl_dereference(ip6n->tnls_wc[0]); + unregister_netdevice_queue(t->dev, &list); + unregister_netdevice_many(&list); +} + +static int __net_init vti6_init_net(struct net *net) +{ + struct vti6_net *ip6n = net_generic(net, vti6_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), "ip6_vti0", + NET_NAME_UNKNOWN, vti6_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 = &vti6_link_ops; + + err = vti6_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: + vti6_dev_free(ip6n->fb_tnl_dev); +err_alloc_dev: + return err; +} + +static void __net_exit vti6_exit_net(struct net *net) +{ + struct vti6_net *ip6n = net_generic(net, vti6_net_id); + + rtnl_lock(); + vti6_destroy_tunnels(ip6n); + rtnl_unlock(); +} + +static struct pernet_operations vti6_net_ops = { + .init = vti6_init_net, + .exit = vti6_exit_net, + .id = &vti6_net_id, + .size = sizeof(struct vti6_net), +}; + +static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { + .handler = vti6_rcv, + .cb_handler = vti6_rcv_cb, + .err_handler = vti6_err, + .priority = 100, +}; + +static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { + .handler = vti6_rcv, + .cb_handler = vti6_rcv_cb, + .err_handler = vti6_err, + .priority = 100, +}; + +static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { + .handler = vti6_rcv, + .cb_handler = vti6_rcv_cb, + .err_handler = vti6_err, + .priority = 100, +}; + +/** + * vti6_tunnel_init - register protocol and reserve needed resources + * + * Return: 0 on success + **/ +static int __init vti6_tunnel_init(void) +{ + const char *msg; + int err; + + msg = "tunnel device"; + err = register_pernet_device(&vti6_net_ops); + if (err < 0) + goto pernet_dev_failed; + + msg = "tunnel protocols"; + err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP); + if (err < 0) + goto xfrm_proto_esp_failed; + err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH); + if (err < 0) + goto xfrm_proto_ah_failed; + err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP); + if (err < 0) + goto xfrm_proto_comp_failed; + + msg = "netlink interface"; + err = rtnl_link_register(&vti6_link_ops); + if (err < 0) + goto rtnl_link_failed; + + return 0; + +rtnl_link_failed: + xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); +xfrm_proto_comp_failed: + xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); +xfrm_proto_ah_failed: + xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); +xfrm_proto_esp_failed: + unregister_pernet_device(&vti6_net_ops); +pernet_dev_failed: + pr_err("vti6 init: failed to register %s\n", msg); + return err; +} + +/** + * vti6_tunnel_cleanup - free resources and unregister protocol + **/ +static void __exit vti6_tunnel_cleanup(void) +{ + rtnl_link_unregister(&vti6_link_ops); + xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP); + xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); + xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); + unregister_pernet_device(&vti6_net_ops); +} + +module_init(vti6_tunnel_init); +module_exit(vti6_tunnel_cleanup); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_RTNL_LINK("vti6"); +MODULE_ALIAS_NETDEV("ip6_vti0"); +MODULE_AUTHOR("Steffen Klassert"); +MODULE_DESCRIPTION("IPv6 virtual tunnel interface"); |