// SPDX-License-Identifier: GPL-2.0-or-later /* * IPv6 virtual tunneling interface * * Copyright (C) 2013 secunet Security Networks AG * * Author: * Steffen Klassert * * Based on: * net/ipv6/ip6_tunnel.c */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define IP6_VTI_HASH_SIZE_SHIFT 5 #define IP6_VTI_HASH_SIZE (1 << IP6_VTI_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, IP6_VTI_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 unsigned 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[IP6_VTI_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 * @ip6n: the private data for ip6_vti in the netns * @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); } 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; dev->rtnl_link_ops = &vti6_link_ops; err = register_netdevice(dev); if (err < 0) goto out; strcpy(t->parms.name, dev->name); 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]) { if (!dev_valid_name(p->name)) goto failed; strscpy(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: free_netdev(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); netdev_put(dev, &t->dev_tracker); } static int vti6_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) { 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(); goto discard; } ipv6h = ipv6_hdr(skb); if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) { t->dev->stats.rx_dropped++; rcu_read_unlock(); goto discard; } rcu_read_unlock(); XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; XFRM_SPI_SKB_CB(skb)->family = AF_INET6; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); return xfrm_input(skb, nexthdr, spi, encap_type); } rcu_read_unlock(); return -EINVAL; discard: kfree_skb(skb); return 0; } static int vti6_rcv(struct sk_buff *skb) { int nexthdr = skb_network_header(skb)[IP6CB(skb)->nhoff]; return vti6_input_proto(skb, nexthdr, 0, 0); } static int vti6_rcv_cb(struct sk_buff *skb, int err) { unsigned short family; struct net_device *dev; struct xfrm_state *x; const struct xfrm_mode *inner_mode; 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); inner_mode = &x->inner_mode; if (x->sel.family == AF_UNSPEC) { inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); if (inner_mode == NULL) { XFRM_INC_STATS(dev_net(skb->dev), LINUX_MIB_XFRMINSTATEMODEERROR); return -EINVAL; } } family = inner_mode->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; dev_sw_netstats_rx_add(dev, skb->len); 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 pkt_len = skb->len; int err = -1; int mtu; if (!dst) { switch (skb->protocol) { case htons(ETH_P_IP): { struct rtable *rt; fl->u.ip4.flowi4_oif = dev->ifindex; fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC; rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4); if (IS_ERR(rt)) goto tx_err_link_failure; dst = &rt->dst; skb_dst_set(skb, dst); break; } case htons(ETH_P_IPV6): fl->u.ip6.flowi6_oif = dev->ifindex; fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC; dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6); if (dst->error) { dst_release(dst); dst = NULL; goto tx_err_link_failure; } skb_dst_set(skb, dst); break; default: goto tx_err_link_failure; } } dst_hold(dst); dst = xfrm_lookup_route(t->net, dst, fl, NULL, 0); if (IS_ERR(dst)) { err = PTR_ERR(dst); dst = NULL; goto tx_err_link_failure; } if (dst->flags & DST_XFRM_QUEUE) goto xmit; 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; } mtu = dst_mtu(dst); if (skb->len > mtu) { skb_dst_update_pmtu_no_confirm(skb, mtu); if (skb->protocol == htons(ETH_P_IPV6)) { if (mtu < IPV6_MIN_MTU) mtu = IPV6_MIN_MTU; icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); } else { if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) goto xmit; icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); } err = -EMSGSIZE; goto tx_err_dst_release; } xmit: skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev))); skb_dst_set(skb, dst); skb->dev = skb_dst(skb)->dev; err = dst_output(t->net, skb->sk, skb); if (net_xmit_eval(err) == 0) err = pkt_len; iptunnel_xmit_stats(dev, err); 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 flowi fl; int ret; if (!pskb_inet_may_pull(skb)) goto tx_err; memset(&fl, 0, sizeof(fl)); switch (skb->protocol) { case htons(ETH_P_IPV6): if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) || vti6_addr_conflict(t, ipv6_hdr(skb))) 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, sock_net_uid(net, NULL)); else ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); xfrm_state_put(x); return 0; } static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu) { struct net_device *dev = t->dev; struct __ip6_tnl_parm *p = &t->parms; struct net_device *tdev = NULL; int mtu; __dev_addr_set(dev, &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; if (keep_mtu && dev->mtu) { dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu); return; } 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, NULL, strict); if (rt) tdev = rt->dst.dev; ip6_rt_put(rt); } if (!tdev && p->link) tdev = __dev_get_by_index(t->net, p->link); if (tdev) mtu = tdev->mtu - sizeof(struct ipv6hdr); else mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr); dev->mtu = max_t(int, mtu, IPV4_MIN_MTU); } /** * vti6_tnl_change - update the tunnel parameters * @t: tunnel to be changed * @p: tunnel configuration parameters * @keep_mtu: MTU was set from userspace, don't re-compute it * * Description: * vti6_tnl_change() updates the tunnel parameters **/ static int vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p, bool keep_mtu) { 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; t->parms.fwmark = p->fwmark; dst_cache_reset(&t->dst_cache); vti6_link_config(t, keep_mtu); return 0; } static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p, bool keep_mtu) { 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, keep_mtu); 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; if (u->i_key) u->i_flags |= GRE_KEY; if (u->o_key) u->o_flags |= GRE_KEY; u->proto = p->proto; memcpy(u->name, p->name, sizeof(u->name)); } /** * vti6_siocdevprivate - configure vti6 tunnels from userspace * @dev: virtual device associated with tunnel * @ifr: unused * @data: parameters passed from userspace * @cmd: command to be performed * * Description: * vti6_siocdevprivate() 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_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __user *data, 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); memset(&p1, 0, sizeof(p1)); switch (cmd) { case SIOCGETTUNNEL: if (dev == ip6n->fb_tnl_dev) { if (copy_from_user(&p, 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(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, 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, false); } if (t) { err = 0; vti6_parm_to_user(&p, &t->parms); if (copy_to_user(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, 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; } 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_siocdevprivate = vti6_siocdevprivate, .ndo_get_stats64 = dev_get_tstats64, .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->header_ops = &ip_tunnel_header_ops; dev->needs_free_netdev = true; dev->priv_destructor = vti6_dev_free; dev->type = ARPHRD_TUNNEL6; dev->min_mtu = IPV4_MIN_MTU; dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr); dev->flags |= IFF_NOARP; dev->addr_len = sizeof(struct in6_addr); netif_keep_dst(dev); /* This perm addr will be used as interface identifier by IPv6 */ dev->addr_assign_type = NET_ADDR_RANDOM; eth_random_addr(dev->perm_addr); } /** * 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; netdev_hold(dev, &t->dev_tracker, GFP_KERNEL); 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, true); 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; rcu_assign_pointer(ip6n->tnls_wc[0], t); return 0; } static int vti6_validate(struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { 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]); if (data[IFLA_VTI_FWMARK]) parms->fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]); } static int vti6_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { 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 netlink_ext_ack *extack) { 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, tb && tb[IFLA_MTU]); } 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) + /* IFLA_VTI_FWMARK */ 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) || nla_put_u32(skb, IFLA_VTI_FWMARK, parm->fwmark)) 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 }, [IFLA_VTI_FWMARK] = { .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, struct list_head *list) { int h; struct ip6_tnl *t; for (h = 0; h < IP6_VTI_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]); if (t) unregister_netdevice_queue(t->dev, 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; if (!net_has_fallback_tunnels(net)) return 0; 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: free_netdev(ip6n->fb_tnl_dev); err_alloc_dev: return err; } static void __net_exit vti6_exit_batch_net(struct list_head *net_list) { struct vti6_net *ip6n; struct net *net; LIST_HEAD(list); rtnl_lock(); list_for_each_entry(net, net_list, exit_list) { ip6n = net_generic(net, vti6_net_id); vti6_destroy_tunnels(ip6n, &list); } unregister_netdevice_many(&list); rtnl_unlock(); } static struct pernet_operations vti6_net_ops = { .init = vti6_init_net, .exit_batch = vti6_exit_batch_net, .id = &vti6_net_id, .size = sizeof(struct vti6_net), }; static struct xfrm6_protocol vti_esp6_protocol __read_mostly = { .handler = vti6_rcv, .input_handler = vti6_input_proto, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 100, }; static struct xfrm6_protocol vti_ah6_protocol __read_mostly = { .handler = vti6_rcv, .input_handler = vti6_input_proto, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 100, }; static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { .handler = vti6_rcv, .input_handler = vti6_input_proto, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 100, }; #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) static int vti6_rcv_tunnel(struct sk_buff *skb) { const xfrm_address_t *saddr; __be32 spi; saddr = (const xfrm_address_t *)&ipv6_hdr(skb)->saddr; spi = xfrm6_tunnel_spi_lookup(dev_net(skb->dev), saddr); return vti6_input_proto(skb, IPPROTO_IPV6, spi, 0); } static struct xfrm6_tunnel vti_ipv6_handler __read_mostly = { .handler = vti6_rcv_tunnel, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 0, }; static struct xfrm6_tunnel vti_ip6ip_handler __read_mostly = { .handler = vti6_rcv_tunnel, .cb_handler = vti6_rcv_cb, .err_handler = vti6_err, .priority = 0, }; #endif /** * 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; #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) msg = "ipv6 tunnel"; err = xfrm6_tunnel_register(&vti_ipv6_handler, AF_INET6); if (err < 0) goto vti_tunnel_ipv6_failed; err = xfrm6_tunnel_register(&vti_ip6ip_handler, AF_INET); if (err < 0) goto vti_tunnel_ip6ip_failed; #endif msg = "netlink interface"; err = rtnl_link_register(&vti6_link_ops); if (err < 0) goto rtnl_link_failed; return 0; rtnl_link_failed: #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) err = xfrm6_tunnel_deregister(&vti_ip6ip_handler, AF_INET); vti_tunnel_ip6ip_failed: err = xfrm6_tunnel_deregister(&vti_ipv6_handler, AF_INET6); vti_tunnel_ipv6_failed: #endif 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); #if IS_REACHABLE(CONFIG_INET6_XFRM_TUNNEL) xfrm6_tunnel_deregister(&vti_ip6ip_handler, AF_INET); xfrm6_tunnel_deregister(&vti_ipv6_handler, AF_INET6); #endif 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");