diff options
Diffstat (limited to 'net/ipv4/ip_tunnel.c')
| -rw-r--r-- | net/ipv4/ip_tunnel.c | 1279 |
1 files changed, 1279 insertions, 0 deletions
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c new file mode 100644 index 000000000..99f70b990 --- /dev/null +++ b/net/ipv4/ip_tunnel.c @@ -0,0 +1,1279 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2013 Nicira, Inc. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/capability.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/in.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/if_arp.h> +#include <linux/init.h> +#include <linux/in6.h> +#include <linux/inetdevice.h> +#include <linux/igmp.h> +#include <linux/netfilter_ipv4.h> +#include <linux/etherdevice.h> +#include <linux/if_ether.h> +#include <linux/if_vlan.h> +#include <linux/rculist.h> +#include <linux/err.h> + +#include <net/sock.h> +#include <net/ip.h> +#include <net/icmp.h> +#include <net/protocol.h> +#include <net/ip_tunnels.h> +#include <net/arp.h> +#include <net/checksum.h> +#include <net/dsfield.h> +#include <net/inet_ecn.h> +#include <net/xfrm.h> +#include <net/net_namespace.h> +#include <net/netns/generic.h> +#include <net/rtnetlink.h> +#include <net/udp.h> +#include <net/dst_metadata.h> + +#if IS_ENABLED(CONFIG_IPV6) +#include <net/ipv6.h> +#include <net/ip6_fib.h> +#include <net/ip6_route.h> +#endif + +static unsigned int ip_tunnel_hash(__be32 key, __be32 remote) +{ + return hash_32((__force u32)key ^ (__force u32)remote, + IP_TNL_HASH_BITS); +} + +static bool ip_tunnel_key_match(const struct ip_tunnel_parm *p, + __be16 flags, __be32 key) +{ + if (p->i_flags & TUNNEL_KEY) { + if (flags & TUNNEL_KEY) + return key == p->i_key; + else + /* key expected, none present */ + return false; + } else + return !(flags & TUNNEL_KEY); +} + +/* Fallback tunnel: no source, no destination, no key, no options + + Tunnel hash table: + We require exact key match i.e. if a key is present in packet + it will match only tunnel with the same key; if it is not present, + it will match only keyless tunnel. + + All keysless packets, if not matched configured keyless tunnels + will match fallback tunnel. + Given src, dst and key, find appropriate for input tunnel. +*/ +struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn, + int link, __be16 flags, + __be32 remote, __be32 local, + __be32 key) +{ + struct ip_tunnel *t, *cand = NULL; + struct hlist_head *head; + struct net_device *ndev; + unsigned int hash; + + hash = ip_tunnel_hash(key, remote); + head = &itn->tunnels[hash]; + + hlist_for_each_entry_rcu(t, head, hash_node) { + if (local != t->parms.iph.saddr || + remote != t->parms.iph.daddr || + !(t->dev->flags & IFF_UP)) + continue; + + if (!ip_tunnel_key_match(&t->parms, flags, key)) + continue; + + if (t->parms.link == link) + return t; + else + cand = t; + } + + hlist_for_each_entry_rcu(t, head, hash_node) { + if (remote != t->parms.iph.daddr || + t->parms.iph.saddr != 0 || + !(t->dev->flags & IFF_UP)) + continue; + + if (!ip_tunnel_key_match(&t->parms, flags, key)) + continue; + + if (t->parms.link == link) + return t; + else if (!cand) + cand = t; + } + + hash = ip_tunnel_hash(key, 0); + head = &itn->tunnels[hash]; + + hlist_for_each_entry_rcu(t, head, hash_node) { + if ((local != t->parms.iph.saddr || t->parms.iph.daddr != 0) && + (local != t->parms.iph.daddr || !ipv4_is_multicast(local))) + continue; + + if (!(t->dev->flags & IFF_UP)) + continue; + + if (!ip_tunnel_key_match(&t->parms, flags, key)) + continue; + + if (t->parms.link == link) + return t; + else if (!cand) + cand = t; + } + + hlist_for_each_entry_rcu(t, head, hash_node) { + if ((!(flags & TUNNEL_NO_KEY) && t->parms.i_key != key) || + t->parms.iph.saddr != 0 || + t->parms.iph.daddr != 0 || + !(t->dev->flags & IFF_UP)) + continue; + + if (t->parms.link == link) + return t; + else if (!cand) + cand = t; + } + + if (cand) + return cand; + + t = rcu_dereference(itn->collect_md_tun); + if (t && t->dev->flags & IFF_UP) + return t; + + ndev = READ_ONCE(itn->fb_tunnel_dev); + if (ndev && ndev->flags & IFF_UP) + return netdev_priv(ndev); + + return NULL; +} +EXPORT_SYMBOL_GPL(ip_tunnel_lookup); + +static struct hlist_head *ip_bucket(struct ip_tunnel_net *itn, + struct ip_tunnel_parm *parms) +{ + unsigned int h; + __be32 remote; + __be32 i_key = parms->i_key; + + if (parms->iph.daddr && !ipv4_is_multicast(parms->iph.daddr)) + remote = parms->iph.daddr; + else + remote = 0; + + if (!(parms->i_flags & TUNNEL_KEY) && (parms->i_flags & VTI_ISVTI)) + i_key = 0; + + h = ip_tunnel_hash(i_key, remote); + return &itn->tunnels[h]; +} + +static void ip_tunnel_add(struct ip_tunnel_net *itn, struct ip_tunnel *t) +{ + struct hlist_head *head = ip_bucket(itn, &t->parms); + + if (t->collect_md) + rcu_assign_pointer(itn->collect_md_tun, t); + hlist_add_head_rcu(&t->hash_node, head); +} + +static void ip_tunnel_del(struct ip_tunnel_net *itn, struct ip_tunnel *t) +{ + if (t->collect_md) + rcu_assign_pointer(itn->collect_md_tun, NULL); + hlist_del_init_rcu(&t->hash_node); +} + +static struct ip_tunnel *ip_tunnel_find(struct ip_tunnel_net *itn, + struct ip_tunnel_parm *parms, + int type) +{ + __be32 remote = parms->iph.daddr; + __be32 local = parms->iph.saddr; + __be32 key = parms->i_key; + __be16 flags = parms->i_flags; + int link = parms->link; + struct ip_tunnel *t = NULL; + struct hlist_head *head = ip_bucket(itn, parms); + + hlist_for_each_entry_rcu(t, head, hash_node) { + if (local == t->parms.iph.saddr && + remote == t->parms.iph.daddr && + link == t->parms.link && + type == t->dev->type && + ip_tunnel_key_match(&t->parms, flags, key)) + break; + } + return t; +} + +static struct net_device *__ip_tunnel_create(struct net *net, + const struct rtnl_link_ops *ops, + struct ip_tunnel_parm *parms) +{ + int err; + struct ip_tunnel *tunnel; + struct net_device *dev; + char name[IFNAMSIZ]; + + err = -E2BIG; + if (parms->name[0]) { + if (!dev_valid_name(parms->name)) + goto failed; + strlcpy(name, parms->name, IFNAMSIZ); + } else { + if (strlen(ops->kind) > (IFNAMSIZ - 3)) + goto failed; + strcpy(name, ops->kind); + strcat(name, "%d"); + } + + ASSERT_RTNL(); + dev = alloc_netdev(ops->priv_size, name, NET_NAME_UNKNOWN, ops->setup); + if (!dev) { + err = -ENOMEM; + goto failed; + } + dev_net_set(dev, net); + + dev->rtnl_link_ops = ops; + + tunnel = netdev_priv(dev); + tunnel->parms = *parms; + tunnel->net = net; + + err = register_netdevice(dev); + if (err) + goto failed_free; + + return dev; + +failed_free: + free_netdev(dev); +failed: + return ERR_PTR(err); +} + +static int ip_tunnel_bind_dev(struct net_device *dev) +{ + struct net_device *tdev = NULL; + struct ip_tunnel *tunnel = netdev_priv(dev); + const struct iphdr *iph; + int hlen = LL_MAX_HEADER; + int mtu = ETH_DATA_LEN; + int t_hlen = tunnel->hlen + sizeof(struct iphdr); + + iph = &tunnel->parms.iph; + + /* Guess output device to choose reasonable mtu and needed_headroom */ + if (iph->daddr) { + struct flowi4 fl4; + struct rtable *rt; + + ip_tunnel_init_flow(&fl4, iph->protocol, iph->daddr, + iph->saddr, tunnel->parms.o_key, + RT_TOS(iph->tos), tunnel->parms.link, + tunnel->fwmark, 0); + rt = ip_route_output_key(tunnel->net, &fl4); + + if (!IS_ERR(rt)) { + tdev = rt->dst.dev; + ip_rt_put(rt); + } + if (dev->type != ARPHRD_ETHER) + dev->flags |= IFF_POINTOPOINT; + + dst_cache_reset(&tunnel->dst_cache); + } + + if (!tdev && tunnel->parms.link) + tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link); + + if (tdev) { + hlen = tdev->hard_header_len + tdev->needed_headroom; + mtu = min(tdev->mtu, IP_MAX_MTU); + } + + dev->needed_headroom = t_hlen + hlen; + mtu -= t_hlen + (dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0); + + if (mtu < IPV4_MIN_MTU) + mtu = IPV4_MIN_MTU; + + return mtu; +} + +static struct ip_tunnel *ip_tunnel_create(struct net *net, + struct ip_tunnel_net *itn, + struct ip_tunnel_parm *parms) +{ + struct ip_tunnel *nt; + struct net_device *dev; + int t_hlen; + int mtu; + int err; + + dev = __ip_tunnel_create(net, itn->rtnl_link_ops, parms); + if (IS_ERR(dev)) + return ERR_CAST(dev); + + mtu = ip_tunnel_bind_dev(dev); + err = dev_set_mtu(dev, mtu); + if (err) + goto err_dev_set_mtu; + + nt = netdev_priv(dev); + t_hlen = nt->hlen + sizeof(struct iphdr); + dev->min_mtu = ETH_MIN_MTU; + dev->max_mtu = IP_MAX_MTU - t_hlen; + if (dev->type == ARPHRD_ETHER) + dev->max_mtu -= dev->hard_header_len; + + ip_tunnel_add(itn, nt); + return nt; + +err_dev_set_mtu: + unregister_netdevice(dev); + return ERR_PTR(err); +} + +int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb, + const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst, + bool log_ecn_error) +{ + const struct iphdr *iph = ip_hdr(skb); + int err; + +#ifdef CONFIG_NET_IPGRE_BROADCAST + if (ipv4_is_multicast(iph->daddr)) { + tunnel->dev->stats.multicast++; + skb->pkt_type = PACKET_BROADCAST; + } +#endif + + if ((!(tpi->flags&TUNNEL_CSUM) && (tunnel->parms.i_flags&TUNNEL_CSUM)) || + ((tpi->flags&TUNNEL_CSUM) && !(tunnel->parms.i_flags&TUNNEL_CSUM))) { + tunnel->dev->stats.rx_crc_errors++; + tunnel->dev->stats.rx_errors++; + goto drop; + } + + if (tunnel->parms.i_flags&TUNNEL_SEQ) { + if (!(tpi->flags&TUNNEL_SEQ) || + (tunnel->i_seqno && (s32)(ntohl(tpi->seq) - tunnel->i_seqno) < 0)) { + tunnel->dev->stats.rx_fifo_errors++; + tunnel->dev->stats.rx_errors++; + goto drop; + } + tunnel->i_seqno = ntohl(tpi->seq) + 1; + } + + skb_set_network_header(skb, (tunnel->dev->type == ARPHRD_ETHER) ? ETH_HLEN : 0); + + err = IP_ECN_decapsulate(iph, skb); + if (unlikely(err)) { + if (log_ecn_error) + net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", + &iph->saddr, iph->tos); + if (err > 1) { + ++tunnel->dev->stats.rx_frame_errors; + ++tunnel->dev->stats.rx_errors; + goto drop; + } + } + + dev_sw_netstats_rx_add(tunnel->dev, skb->len); + skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev))); + + if (tunnel->dev->type == ARPHRD_ETHER) { + skb->protocol = eth_type_trans(skb, tunnel->dev); + skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); + } else { + skb->dev = tunnel->dev; + } + + if (tun_dst) + skb_dst_set(skb, (struct dst_entry *)tun_dst); + + gro_cells_receive(&tunnel->gro_cells, skb); + return 0; + +drop: + if (tun_dst) + dst_release((struct dst_entry *)tun_dst); + kfree_skb(skb); + return 0; +} +EXPORT_SYMBOL_GPL(ip_tunnel_rcv); + +int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops, + unsigned int num) +{ + if (num >= MAX_IPTUN_ENCAP_OPS) + return -ERANGE; + + return !cmpxchg((const struct ip_tunnel_encap_ops **) + &iptun_encaps[num], + NULL, ops) ? 0 : -1; +} +EXPORT_SYMBOL(ip_tunnel_encap_add_ops); + +int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops, + unsigned int num) +{ + int ret; + + if (num >= MAX_IPTUN_ENCAP_OPS) + return -ERANGE; + + ret = (cmpxchg((const struct ip_tunnel_encap_ops **) + &iptun_encaps[num], + ops, NULL) == ops) ? 0 : -1; + + synchronize_net(); + + return ret; +} +EXPORT_SYMBOL(ip_tunnel_encap_del_ops); + +int ip_tunnel_encap_setup(struct ip_tunnel *t, + struct ip_tunnel_encap *ipencap) +{ + int hlen; + + memset(&t->encap, 0, sizeof(t->encap)); + + hlen = ip_encap_hlen(ipencap); + if (hlen < 0) + return hlen; + + t->encap.type = ipencap->type; + t->encap.sport = ipencap->sport; + t->encap.dport = ipencap->dport; + t->encap.flags = ipencap->flags; + + t->encap_hlen = hlen; + t->hlen = t->encap_hlen + t->tun_hlen; + + return 0; +} +EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup); + +static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb, + struct rtable *rt, __be16 df, + const struct iphdr *inner_iph, + int tunnel_hlen, __be32 dst, bool md) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + int pkt_size; + int mtu; + + tunnel_hlen = md ? tunnel_hlen : tunnel->hlen; + pkt_size = skb->len - tunnel_hlen; + pkt_size -= dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0; + + if (df) { + mtu = dst_mtu(&rt->dst) - (sizeof(struct iphdr) + tunnel_hlen); + mtu -= dev->type == ARPHRD_ETHER ? dev->hard_header_len : 0; + } else { + mtu = skb_valid_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu; + } + + if (skb_valid_dst(skb)) + skb_dst_update_pmtu_no_confirm(skb, mtu); + + if (skb->protocol == htons(ETH_P_IP)) { + if (!skb_is_gso(skb) && + (inner_iph->frag_off & htons(IP_DF)) && + mtu < pkt_size) { + icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); + return -E2BIG; + } + } +#if IS_ENABLED(CONFIG_IPV6) + else if (skb->protocol == htons(ETH_P_IPV6)) { + struct rt6_info *rt6; + __be32 daddr; + + rt6 = skb_valid_dst(skb) ? (struct rt6_info *)skb_dst(skb) : + NULL; + daddr = md ? dst : tunnel->parms.iph.daddr; + + if (rt6 && mtu < dst_mtu(skb_dst(skb)) && + mtu >= IPV6_MIN_MTU) { + if ((daddr && !ipv4_is_multicast(daddr)) || + rt6->rt6i_dst.plen == 128) { + rt6->rt6i_flags |= RTF_MODIFIED; + dst_metric_set(skb_dst(skb), RTAX_MTU, mtu); + } + } + + if (!skb_is_gso(skb) && mtu >= IPV6_MIN_MTU && + mtu < pkt_size) { + icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); + return -E2BIG; + } + } +#endif + return 0; +} + +void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, + u8 proto, int tunnel_hlen) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + u32 headroom = sizeof(struct iphdr); + struct ip_tunnel_info *tun_info; + const struct ip_tunnel_key *key; + const struct iphdr *inner_iph; + struct rtable *rt = NULL; + struct flowi4 fl4; + __be16 df = 0; + u8 tos, ttl; + bool use_cache; + + tun_info = skb_tunnel_info(skb); + if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || + ip_tunnel_info_af(tun_info) != AF_INET)) + goto tx_error; + key = &tun_info->key; + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); + inner_iph = (const struct iphdr *)skb_inner_network_header(skb); + tos = key->tos; + if (tos == 1) { + if (skb->protocol == htons(ETH_P_IP)) + tos = inner_iph->tos; + else if (skb->protocol == htons(ETH_P_IPV6)) + tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); + } + ip_tunnel_init_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, + tunnel_id_to_key32(key->tun_id), RT_TOS(tos), + 0, skb->mark, skb_get_hash(skb)); + if (tunnel->encap.type != TUNNEL_ENCAP_NONE) + goto tx_error; + + use_cache = ip_tunnel_dst_cache_usable(skb, tun_info); + if (use_cache) + rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl4.saddr); + if (!rt) { + rt = ip_route_output_key(tunnel->net, &fl4); + if (IS_ERR(rt)) { + dev->stats.tx_carrier_errors++; + goto tx_error; + } + if (use_cache) + dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst, + fl4.saddr); + } + if (rt->dst.dev == dev) { + ip_rt_put(rt); + dev->stats.collisions++; + goto tx_error; + } + + if (key->tun_flags & TUNNEL_DONT_FRAGMENT) + df = htons(IP_DF); + if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen, + key->u.ipv4.dst, true)) { + ip_rt_put(rt); + goto tx_error; + } + + tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); + ttl = key->ttl; + if (ttl == 0) { + if (skb->protocol == htons(ETH_P_IP)) + ttl = inner_iph->ttl; + else if (skb->protocol == htons(ETH_P_IPV6)) + ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; + else + ttl = ip4_dst_hoplimit(&rt->dst); + } + + headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len; + if (headroom > READ_ONCE(dev->needed_headroom)) + WRITE_ONCE(dev->needed_headroom, headroom); + + if (skb_cow_head(skb, READ_ONCE(dev->needed_headroom))) { + ip_rt_put(rt); + goto tx_dropped; + } + iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, tos, ttl, + df, !net_eq(tunnel->net, dev_net(dev))); + return; +tx_error: + dev->stats.tx_errors++; + goto kfree; +tx_dropped: + dev->stats.tx_dropped++; +kfree: + kfree_skb(skb); +} +EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit); + +void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, + const struct iphdr *tnl_params, u8 protocol) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + struct ip_tunnel_info *tun_info = NULL; + const struct iphdr *inner_iph; + unsigned int max_headroom; /* The extra header space needed */ + struct rtable *rt = NULL; /* Route to the other host */ + bool use_cache = false; + struct flowi4 fl4; + bool md = false; + bool connected; + u8 tos, ttl; + __be32 dst; + __be16 df; + + inner_iph = (const struct iphdr *)skb_inner_network_header(skb); + connected = (tunnel->parms.iph.daddr != 0); + + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); + + dst = tnl_params->daddr; + if (dst == 0) { + /* NBMA tunnel */ + + if (!skb_dst(skb)) { + dev->stats.tx_fifo_errors++; + goto tx_error; + } + + tun_info = skb_tunnel_info(skb); + if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX) && + ip_tunnel_info_af(tun_info) == AF_INET && + tun_info->key.u.ipv4.dst) { + dst = tun_info->key.u.ipv4.dst; + md = true; + connected = true; + } + else if (skb->protocol == htons(ETH_P_IP)) { + rt = skb_rtable(skb); + dst = rt_nexthop(rt, inner_iph->daddr); + } +#if IS_ENABLED(CONFIG_IPV6) + else if (skb->protocol == htons(ETH_P_IPV6)) { + const struct in6_addr *addr6; + struct neighbour *neigh; + bool do_tx_error_icmp; + int addr_type; + + neigh = dst_neigh_lookup(skb_dst(skb), + &ipv6_hdr(skb)->daddr); + if (!neigh) + goto tx_error; + + addr6 = (const struct in6_addr *)&neigh->primary_key; + addr_type = ipv6_addr_type(addr6); + + if (addr_type == IPV6_ADDR_ANY) { + addr6 = &ipv6_hdr(skb)->daddr; + addr_type = ipv6_addr_type(addr6); + } + + if ((addr_type & IPV6_ADDR_COMPATv4) == 0) + do_tx_error_icmp = true; + else { + do_tx_error_icmp = false; + dst = addr6->s6_addr32[3]; + } + neigh_release(neigh); + if (do_tx_error_icmp) + goto tx_error_icmp; + } +#endif + else + goto tx_error; + + if (!md) + connected = false; + } + + tos = tnl_params->tos; + if (tos & 0x1) { + tos &= ~0x1; + if (skb->protocol == htons(ETH_P_IP)) { + tos = inner_iph->tos; + connected = false; + } else if (skb->protocol == htons(ETH_P_IPV6)) { + tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph); + connected = false; + } + } + + ip_tunnel_init_flow(&fl4, protocol, dst, tnl_params->saddr, + tunnel->parms.o_key, RT_TOS(tos), tunnel->parms.link, + tunnel->fwmark, skb_get_hash(skb)); + + if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) + goto tx_error; + + if (connected && md) { + use_cache = ip_tunnel_dst_cache_usable(skb, tun_info); + if (use_cache) + rt = dst_cache_get_ip4(&tun_info->dst_cache, + &fl4.saddr); + } else { + rt = connected ? dst_cache_get_ip4(&tunnel->dst_cache, + &fl4.saddr) : NULL; + } + + if (!rt) { + rt = ip_route_output_key(tunnel->net, &fl4); + + if (IS_ERR(rt)) { + dev->stats.tx_carrier_errors++; + goto tx_error; + } + if (use_cache) + dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst, + fl4.saddr); + else if (!md && connected) + dst_cache_set_ip4(&tunnel->dst_cache, &rt->dst, + fl4.saddr); + } + + if (rt->dst.dev == dev) { + ip_rt_put(rt); + dev->stats.collisions++; + goto tx_error; + } + + df = tnl_params->frag_off; + if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) + df |= (inner_iph->frag_off & htons(IP_DF)); + + if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, 0, 0, false)) { + ip_rt_put(rt); + goto tx_error; + } + + if (tunnel->err_count > 0) { + if (time_before(jiffies, + tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { + tunnel->err_count--; + + dst_link_failure(skb); + } else + tunnel->err_count = 0; + } + + tos = ip_tunnel_ecn_encap(tos, inner_iph, skb); + ttl = tnl_params->ttl; + if (ttl == 0) { + if (skb->protocol == htons(ETH_P_IP)) + ttl = inner_iph->ttl; +#if IS_ENABLED(CONFIG_IPV6) + else if (skb->protocol == htons(ETH_P_IPV6)) + ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit; +#endif + else + ttl = ip4_dst_hoplimit(&rt->dst); + } + + max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) + + rt->dst.header_len + ip_encap_hlen(&tunnel->encap); + if (max_headroom > READ_ONCE(dev->needed_headroom)) + WRITE_ONCE(dev->needed_headroom, max_headroom); + + if (skb_cow_head(skb, READ_ONCE(dev->needed_headroom))) { + ip_rt_put(rt); + dev->stats.tx_dropped++; + kfree_skb(skb); + return; + } + + iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl, + df, !net_eq(tunnel->net, dev_net(dev))); + return; + +#if IS_ENABLED(CONFIG_IPV6) +tx_error_icmp: + dst_link_failure(skb); +#endif +tx_error: + dev->stats.tx_errors++; + kfree_skb(skb); +} +EXPORT_SYMBOL_GPL(ip_tunnel_xmit); + +static void ip_tunnel_update(struct ip_tunnel_net *itn, + struct ip_tunnel *t, + struct net_device *dev, + struct ip_tunnel_parm *p, + bool set_mtu, + __u32 fwmark) +{ + ip_tunnel_del(itn, t); + t->parms.iph.saddr = p->iph.saddr; + t->parms.iph.daddr = p->iph.daddr; + t->parms.i_key = p->i_key; + t->parms.o_key = p->o_key; + if (dev->type != ARPHRD_ETHER) { + memcpy(dev->dev_addr, &p->iph.saddr, 4); + memcpy(dev->broadcast, &p->iph.daddr, 4); + } + ip_tunnel_add(itn, t); + + t->parms.iph.ttl = p->iph.ttl; + t->parms.iph.tos = p->iph.tos; + t->parms.iph.frag_off = p->iph.frag_off; + + if (t->parms.link != p->link || t->fwmark != fwmark) { + int mtu; + + t->parms.link = p->link; + t->fwmark = fwmark; + mtu = ip_tunnel_bind_dev(dev); + if (set_mtu) + dev->mtu = mtu; + } + dst_cache_reset(&t->dst_cache); + netdev_state_change(dev); +} + +int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) +{ + int err = 0; + struct ip_tunnel *t = netdev_priv(dev); + struct net *net = t->net; + struct ip_tunnel_net *itn = net_generic(net, t->ip_tnl_net_id); + + switch (cmd) { + case SIOCGETTUNNEL: + if (dev == itn->fb_tunnel_dev) { + t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); + if (!t) + t = netdev_priv(dev); + } + memcpy(p, &t->parms, sizeof(*p)); + break; + + case SIOCADDTUNNEL: + case SIOCCHGTUNNEL: + err = -EPERM; + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + goto done; + if (p->iph.ttl) + p->iph.frag_off |= htons(IP_DF); + if (!(p->i_flags & VTI_ISVTI)) { + if (!(p->i_flags & TUNNEL_KEY)) + p->i_key = 0; + if (!(p->o_flags & TUNNEL_KEY)) + p->o_key = 0; + } + + t = ip_tunnel_find(itn, p, itn->type); + + if (cmd == SIOCADDTUNNEL) { + if (!t) { + t = ip_tunnel_create(net, itn, p); + err = PTR_ERR_OR_ZERO(t); + break; + } + + err = -EEXIST; + break; + } + if (dev != itn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) { + if (t) { + if (t->dev != dev) { + err = -EEXIST; + break; + } + } else { + unsigned int nflags = 0; + + if (ipv4_is_multicast(p->iph.daddr)) + nflags = IFF_BROADCAST; + else if (p->iph.daddr) + nflags = IFF_POINTOPOINT; + + if ((dev->flags^nflags)&(IFF_POINTOPOINT|IFF_BROADCAST)) { + err = -EINVAL; + break; + } + + t = netdev_priv(dev); + } + } + + if (t) { + err = 0; + ip_tunnel_update(itn, t, dev, p, true, 0); + } else { + err = -ENOENT; + } + break; + + case SIOCDELTUNNEL: + err = -EPERM; + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + goto done; + + if (dev == itn->fb_tunnel_dev) { + err = -ENOENT; + t = ip_tunnel_find(itn, p, itn->fb_tunnel_dev->type); + if (!t) + goto done; + err = -EPERM; + if (t == netdev_priv(itn->fb_tunnel_dev)) + goto done; + dev = t->dev; + } + unregister_netdevice(dev); + err = 0; + break; + + default: + err = -EINVAL; + } + +done: + return err; +} +EXPORT_SYMBOL_GPL(ip_tunnel_ctl); + +int ip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) +{ + struct ip_tunnel_parm p; + int err; + + if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) + return -EFAULT; + err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, cmd); + if (!err && copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) + return -EFAULT; + return err; +} +EXPORT_SYMBOL_GPL(ip_tunnel_ioctl); + +int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + int t_hlen = tunnel->hlen + sizeof(struct iphdr); + int max_mtu = IP_MAX_MTU - t_hlen; + + if (dev->type == ARPHRD_ETHER) + max_mtu -= dev->hard_header_len; + + if (new_mtu < ETH_MIN_MTU) + return -EINVAL; + + if (new_mtu > max_mtu) { + if (strict) + return -EINVAL; + + new_mtu = max_mtu; + } + + dev->mtu = new_mtu; + return 0; +} +EXPORT_SYMBOL_GPL(__ip_tunnel_change_mtu); + +int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu) +{ + return __ip_tunnel_change_mtu(dev, new_mtu, true); +} +EXPORT_SYMBOL_GPL(ip_tunnel_change_mtu); + +static void ip_tunnel_dev_free(struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + + gro_cells_destroy(&tunnel->gro_cells); + dst_cache_destroy(&tunnel->dst_cache); + free_percpu(dev->tstats); +} + +void ip_tunnel_dellink(struct net_device *dev, struct list_head *head) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + struct ip_tunnel_net *itn; + + itn = net_generic(tunnel->net, tunnel->ip_tnl_net_id); + + if (itn->fb_tunnel_dev != dev) { + ip_tunnel_del(itn, netdev_priv(dev)); + unregister_netdevice_queue(dev, head); + } +} +EXPORT_SYMBOL_GPL(ip_tunnel_dellink); + +struct net *ip_tunnel_get_link_net(const struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + + return tunnel->net; +} +EXPORT_SYMBOL(ip_tunnel_get_link_net); + +int ip_tunnel_get_iflink(const struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + + return tunnel->parms.link; +} +EXPORT_SYMBOL(ip_tunnel_get_iflink); + +int ip_tunnel_init_net(struct net *net, unsigned int ip_tnl_net_id, + struct rtnl_link_ops *ops, char *devname) +{ + struct ip_tunnel_net *itn = net_generic(net, ip_tnl_net_id); + struct ip_tunnel_parm parms; + unsigned int i; + + itn->rtnl_link_ops = ops; + for (i = 0; i < IP_TNL_HASH_SIZE; i++) + INIT_HLIST_HEAD(&itn->tunnels[i]); + + if (!ops || !net_has_fallback_tunnels(net)) { + struct ip_tunnel_net *it_init_net; + + it_init_net = net_generic(&init_net, ip_tnl_net_id); + itn->type = it_init_net->type; + itn->fb_tunnel_dev = NULL; + return 0; + } + + memset(&parms, 0, sizeof(parms)); + if (devname) + strlcpy(parms.name, devname, IFNAMSIZ); + + rtnl_lock(); + itn->fb_tunnel_dev = __ip_tunnel_create(net, ops, &parms); + /* FB netdevice is special: we have one, and only one per netns. + * Allowing to move it to another netns is clearly unsafe. + */ + if (!IS_ERR(itn->fb_tunnel_dev)) { + itn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL; + itn->fb_tunnel_dev->mtu = ip_tunnel_bind_dev(itn->fb_tunnel_dev); + ip_tunnel_add(itn, netdev_priv(itn->fb_tunnel_dev)); + itn->type = itn->fb_tunnel_dev->type; + } + rtnl_unlock(); + + return PTR_ERR_OR_ZERO(itn->fb_tunnel_dev); +} +EXPORT_SYMBOL_GPL(ip_tunnel_init_net); + +static void ip_tunnel_destroy(struct net *net, struct ip_tunnel_net *itn, + struct list_head *head, + struct rtnl_link_ops *ops) +{ + struct net_device *dev, *aux; + int h; + + for_each_netdev_safe(net, dev, aux) + if (dev->rtnl_link_ops == ops) + unregister_netdevice_queue(dev, head); + + for (h = 0; h < IP_TNL_HASH_SIZE; h++) { + struct ip_tunnel *t; + struct hlist_node *n; + struct hlist_head *thead = &itn->tunnels[h]; + + hlist_for_each_entry_safe(t, n, thead, hash_node) + /* 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, head); + } +} + +void ip_tunnel_delete_nets(struct list_head *net_list, unsigned int id, + struct rtnl_link_ops *ops) +{ + struct ip_tunnel_net *itn; + struct net *net; + LIST_HEAD(list); + + rtnl_lock(); + list_for_each_entry(net, net_list, exit_list) { + itn = net_generic(net, id); + ip_tunnel_destroy(net, itn, &list, ops); + } + unregister_netdevice_many(&list); + rtnl_unlock(); +} +EXPORT_SYMBOL_GPL(ip_tunnel_delete_nets); + +int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[], + struct ip_tunnel_parm *p, __u32 fwmark) +{ + struct ip_tunnel *nt; + struct net *net = dev_net(dev); + struct ip_tunnel_net *itn; + int mtu; + int err; + + nt = netdev_priv(dev); + itn = net_generic(net, nt->ip_tnl_net_id); + + if (nt->collect_md) { + if (rtnl_dereference(itn->collect_md_tun)) + return -EEXIST; + } else { + if (ip_tunnel_find(itn, p, dev->type)) + return -EEXIST; + } + + nt->net = net; + nt->parms = *p; + nt->fwmark = fwmark; + err = register_netdevice(dev); + if (err) + goto err_register_netdevice; + + if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS]) + eth_hw_addr_random(dev); + + mtu = ip_tunnel_bind_dev(dev); + if (tb[IFLA_MTU]) { + unsigned int max = IP_MAX_MTU - (nt->hlen + sizeof(struct iphdr)); + + if (dev->type == ARPHRD_ETHER) + max -= dev->hard_header_len; + + mtu = clamp(dev->mtu, (unsigned int)ETH_MIN_MTU, max); + } + + err = dev_set_mtu(dev, mtu); + if (err) + goto err_dev_set_mtu; + + ip_tunnel_add(itn, nt); + return 0; + +err_dev_set_mtu: + unregister_netdevice(dev); +err_register_netdevice: + return err; +} +EXPORT_SYMBOL_GPL(ip_tunnel_newlink); + +int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[], + struct ip_tunnel_parm *p, __u32 fwmark) +{ + struct ip_tunnel *t; + struct ip_tunnel *tunnel = netdev_priv(dev); + struct net *net = tunnel->net; + struct ip_tunnel_net *itn = net_generic(net, tunnel->ip_tnl_net_id); + + if (dev == itn->fb_tunnel_dev) + return -EINVAL; + + t = ip_tunnel_find(itn, p, dev->type); + + if (t) { + if (t->dev != dev) + return -EEXIST; + } else { + t = tunnel; + + if (dev->type != ARPHRD_ETHER) { + unsigned int nflags = 0; + + if (ipv4_is_multicast(p->iph.daddr)) + nflags = IFF_BROADCAST; + else if (p->iph.daddr) + nflags = IFF_POINTOPOINT; + + if ((dev->flags ^ nflags) & + (IFF_POINTOPOINT | IFF_BROADCAST)) + return -EINVAL; + } + } + + ip_tunnel_update(itn, t, dev, p, !tb[IFLA_MTU], fwmark); + return 0; +} +EXPORT_SYMBOL_GPL(ip_tunnel_changelink); + +int ip_tunnel_init(struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + struct iphdr *iph = &tunnel->parms.iph; + int err; + + dev->needs_free_netdev = true; + dev->priv_destructor = ip_tunnel_dev_free; + dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); + if (!dev->tstats) + return -ENOMEM; + + err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL); + if (err) { + free_percpu(dev->tstats); + return err; + } + + err = gro_cells_init(&tunnel->gro_cells, dev); + if (err) { + dst_cache_destroy(&tunnel->dst_cache); + free_percpu(dev->tstats); + return err; + } + + tunnel->dev = dev; + tunnel->net = dev_net(dev); + strcpy(tunnel->parms.name, dev->name); + iph->version = 4; + iph->ihl = 5; + + if (tunnel->collect_md) + netif_keep_dst(dev); + return 0; +} +EXPORT_SYMBOL_GPL(ip_tunnel_init); + +void ip_tunnel_uninit(struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + struct net *net = tunnel->net; + struct ip_tunnel_net *itn; + + itn = net_generic(net, tunnel->ip_tnl_net_id); + ip_tunnel_del(itn, netdev_priv(dev)); + if (itn->fb_tunnel_dev == dev) + WRITE_ONCE(itn->fb_tunnel_dev, NULL); + + dst_cache_reset(&tunnel->dst_cache); +} +EXPORT_SYMBOL_GPL(ip_tunnel_uninit); + +/* Do least required initialization, rest of init is done in tunnel_init call */ +void ip_tunnel_setup(struct net_device *dev, unsigned int net_id) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + tunnel->ip_tnl_net_id = net_id; +} +EXPORT_SYMBOL_GPL(ip_tunnel_setup); + +MODULE_LICENSE("GPL"); |