1 /* 2 * Copyright (c) 2013 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 16 * 02110-1301, USA 17 */ 18 19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 20 21 #include <linux/types.h> 22 #include <linux/kernel.h> 23 #include <linux/skbuff.h> 24 #include <linux/netdevice.h> 25 #include <linux/in.h> 26 #include <linux/if_arp.h> 27 #include <linux/mroute.h> 28 #include <linux/init.h> 29 #include <linux/in6.h> 30 #include <linux/inetdevice.h> 31 #include <linux/netfilter_ipv4.h> 32 #include <linux/etherdevice.h> 33 #include <linux/if_ether.h> 34 #include <linux/if_vlan.h> 35 #include <linux/static_key.h> 36 37 #include <net/ip.h> 38 #include <net/icmp.h> 39 #include <net/protocol.h> 40 #include <net/ip_tunnels.h> 41 #include <net/arp.h> 42 #include <net/checksum.h> 43 #include <net/dsfield.h> 44 #include <net/inet_ecn.h> 45 #include <net/xfrm.h> 46 #include <net/net_namespace.h> 47 #include <net/netns/generic.h> 48 #include <net/rtnetlink.h> 49 50 int iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, 51 __be32 src, __be32 dst, __u8 proto, 52 __u8 tos, __u8 ttl, __be16 df, bool xnet) 53 { 54 int pkt_len = skb->len; 55 struct iphdr *iph; 56 int err; 57 58 skb_scrub_packet(skb, xnet); 59 60 skb_clear_hash(skb); 61 skb_dst_set(skb, &rt->dst); 62 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 63 64 /* Push down and install the IP header. */ 65 skb_push(skb, sizeof(struct iphdr)); 66 skb_reset_network_header(skb); 67 68 iph = ip_hdr(skb); 69 70 iph->version = 4; 71 iph->ihl = sizeof(struct iphdr) >> 2; 72 iph->frag_off = df; 73 iph->protocol = proto; 74 iph->tos = tos; 75 iph->daddr = dst; 76 iph->saddr = src; 77 iph->ttl = ttl; 78 __ip_select_ident(dev_net(rt->dst.dev), iph, 79 skb_shinfo(skb)->gso_segs ?: 1); 80 81 err = ip_local_out_sk(sk, skb); 82 if (unlikely(net_xmit_eval(err))) 83 pkt_len = 0; 84 return pkt_len; 85 } 86 EXPORT_SYMBOL_GPL(iptunnel_xmit); 87 88 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto) 89 { 90 if (unlikely(!pskb_may_pull(skb, hdr_len))) 91 return -ENOMEM; 92 93 skb_pull_rcsum(skb, hdr_len); 94 95 if (inner_proto == htons(ETH_P_TEB)) { 96 struct ethhdr *eh; 97 98 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 99 return -ENOMEM; 100 101 eh = (struct ethhdr *)skb->data; 102 if (likely(eth_proto_is_802_3(eh->h_proto))) 103 skb->protocol = eh->h_proto; 104 else 105 skb->protocol = htons(ETH_P_802_2); 106 107 } else { 108 skb->protocol = inner_proto; 109 } 110 111 nf_reset(skb); 112 secpath_reset(skb); 113 skb_clear_hash_if_not_l4(skb); 114 skb_dst_drop(skb); 115 skb->vlan_tci = 0; 116 skb_set_queue_mapping(skb, 0); 117 skb->pkt_type = PACKET_HOST; 118 return 0; 119 } 120 EXPORT_SYMBOL_GPL(iptunnel_pull_header); 121 122 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, 123 bool csum_help, 124 int gso_type_mask) 125 { 126 int err; 127 128 if (likely(!skb->encapsulation)) { 129 skb_reset_inner_headers(skb); 130 skb->encapsulation = 1; 131 } 132 133 if (skb_is_gso(skb)) { 134 err = skb_unclone(skb, GFP_ATOMIC); 135 if (unlikely(err)) 136 goto error; 137 skb_shinfo(skb)->gso_type |= gso_type_mask; 138 return skb; 139 } 140 141 /* If packet is not gso and we are resolving any partial checksum, 142 * clear encapsulation flag. This allows setting CHECKSUM_PARTIAL 143 * on the outer header without confusing devices that implement 144 * NETIF_F_IP_CSUM with encapsulation. 145 */ 146 if (csum_help) 147 skb->encapsulation = 0; 148 149 if (skb->ip_summed == CHECKSUM_PARTIAL && csum_help) { 150 err = skb_checksum_help(skb); 151 if (unlikely(err)) 152 goto error; 153 } else if (skb->ip_summed != CHECKSUM_PARTIAL) 154 skb->ip_summed = CHECKSUM_NONE; 155 156 return skb; 157 error: 158 kfree_skb(skb); 159 return ERR_PTR(err); 160 } 161 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 162 163 /* Often modified stats are per cpu, other are shared (netdev->stats) */ 164 struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev, 165 struct rtnl_link_stats64 *tot) 166 { 167 int i; 168 169 netdev_stats_to_stats64(tot, &dev->stats); 170 171 for_each_possible_cpu(i) { 172 const struct pcpu_sw_netstats *tstats = 173 per_cpu_ptr(dev->tstats, i); 174 u64 rx_packets, rx_bytes, tx_packets, tx_bytes; 175 unsigned int start; 176 177 do { 178 start = u64_stats_fetch_begin_irq(&tstats->syncp); 179 rx_packets = tstats->rx_packets; 180 tx_packets = tstats->tx_packets; 181 rx_bytes = tstats->rx_bytes; 182 tx_bytes = tstats->tx_bytes; 183 } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); 184 185 tot->rx_packets += rx_packets; 186 tot->tx_packets += tx_packets; 187 tot->rx_bytes += rx_bytes; 188 tot->tx_bytes += tx_bytes; 189 } 190 191 return tot; 192 } 193 EXPORT_SYMBOL_GPL(ip_tunnel_get_stats64); 194 195 static const struct nla_policy ip_tun_policy[LWTUNNEL_IP_MAX + 1] = { 196 [LWTUNNEL_IP_ID] = { .type = NLA_U64 }, 197 [LWTUNNEL_IP_DST] = { .type = NLA_U32 }, 198 [LWTUNNEL_IP_SRC] = { .type = NLA_U32 }, 199 [LWTUNNEL_IP_TTL] = { .type = NLA_U8 }, 200 [LWTUNNEL_IP_TOS] = { .type = NLA_U8 }, 201 [LWTUNNEL_IP_SPORT] = { .type = NLA_U16 }, 202 [LWTUNNEL_IP_DPORT] = { .type = NLA_U16 }, 203 [LWTUNNEL_IP_FLAGS] = { .type = NLA_U16 }, 204 }; 205 206 static int ip_tun_build_state(struct net_device *dev, struct nlattr *attr, 207 struct lwtunnel_state **ts) 208 { 209 struct ip_tunnel_info *tun_info; 210 struct lwtunnel_state *new_state; 211 struct nlattr *tb[LWTUNNEL_IP_MAX + 1]; 212 int err; 213 214 err = nla_parse_nested(tb, LWTUNNEL_IP_MAX, attr, ip_tun_policy); 215 if (err < 0) 216 return err; 217 218 new_state = lwtunnel_state_alloc(sizeof(*tun_info)); 219 if (!new_state) 220 return -ENOMEM; 221 222 new_state->type = LWTUNNEL_ENCAP_IP; 223 224 tun_info = lwt_tun_info(new_state); 225 226 if (tb[LWTUNNEL_IP_ID]) 227 tun_info->key.tun_id = nla_get_u64(tb[LWTUNNEL_IP_ID]); 228 229 if (tb[LWTUNNEL_IP_DST]) 230 tun_info->key.ipv4_dst = nla_get_be32(tb[LWTUNNEL_IP_DST]); 231 232 if (tb[LWTUNNEL_IP_SRC]) 233 tun_info->key.ipv4_src = nla_get_be32(tb[LWTUNNEL_IP_SRC]); 234 235 if (tb[LWTUNNEL_IP_TTL]) 236 tun_info->key.ipv4_ttl = nla_get_u8(tb[LWTUNNEL_IP_TTL]); 237 238 if (tb[LWTUNNEL_IP_TOS]) 239 tun_info->key.ipv4_tos = nla_get_u8(tb[LWTUNNEL_IP_TOS]); 240 241 if (tb[LWTUNNEL_IP_SPORT]) 242 tun_info->key.tp_src = nla_get_be16(tb[LWTUNNEL_IP_SPORT]); 243 244 if (tb[LWTUNNEL_IP_DPORT]) 245 tun_info->key.tp_dst = nla_get_be16(tb[LWTUNNEL_IP_DPORT]); 246 247 if (tb[LWTUNNEL_IP_FLAGS]) 248 tun_info->key.tun_flags = nla_get_u16(tb[LWTUNNEL_IP_FLAGS]); 249 250 tun_info->mode = IP_TUNNEL_INFO_TX; 251 tun_info->options = NULL; 252 tun_info->options_len = 0; 253 254 *ts = new_state; 255 256 return 0; 257 } 258 259 static int ip_tun_fill_encap_info(struct sk_buff *skb, 260 struct lwtunnel_state *lwtstate) 261 { 262 struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate); 263 264 if (nla_put_u64(skb, LWTUNNEL_IP_ID, tun_info->key.tun_id) || 265 nla_put_be32(skb, LWTUNNEL_IP_DST, tun_info->key.ipv4_dst) || 266 nla_put_be32(skb, LWTUNNEL_IP_SRC, tun_info->key.ipv4_src) || 267 nla_put_u8(skb, LWTUNNEL_IP_TOS, tun_info->key.ipv4_tos) || 268 nla_put_u8(skb, LWTUNNEL_IP_TTL, tun_info->key.ipv4_ttl) || 269 nla_put_u16(skb, LWTUNNEL_IP_SPORT, tun_info->key.tp_src) || 270 nla_put_u16(skb, LWTUNNEL_IP_DPORT, tun_info->key.tp_dst) || 271 nla_put_u16(skb, LWTUNNEL_IP_FLAGS, tun_info->key.tun_flags)) 272 return -ENOMEM; 273 274 return 0; 275 } 276 277 static int ip_tun_encap_nlsize(struct lwtunnel_state *lwtstate) 278 { 279 return nla_total_size(8) /* LWTUNNEL_IP_ID */ 280 + nla_total_size(4) /* LWTUNNEL_IP_DST */ 281 + nla_total_size(4) /* LWTUNNEL_IP_SRC */ 282 + nla_total_size(1) /* LWTUNNEL_IP_TOS */ 283 + nla_total_size(1) /* LWTUNNEL_IP_TTL */ 284 + nla_total_size(2) /* LWTUNNEL_IP_SPORT */ 285 + nla_total_size(2) /* LWTUNNEL_IP_DPORT */ 286 + nla_total_size(2); /* LWTUNNEL_IP_FLAGS */ 287 } 288 289 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = { 290 .build_state = ip_tun_build_state, 291 .fill_encap = ip_tun_fill_encap_info, 292 .get_encap_size = ip_tun_encap_nlsize, 293 }; 294 295 void __init ip_tunnel_core_init(void) 296 { 297 lwtunnel_encap_add_ops(&ip_tun_lwt_ops, LWTUNNEL_ENCAP_IP); 298 } 299 300 struct static_key ip_tunnel_metadata_cnt = STATIC_KEY_INIT_FALSE; 301 EXPORT_SYMBOL(ip_tunnel_metadata_cnt); 302 303 void ip_tunnel_need_metadata(void) 304 { 305 static_key_slow_inc(&ip_tunnel_metadata_cnt); 306 } 307 EXPORT_SYMBOL_GPL(ip_tunnel_need_metadata); 308 309 void ip_tunnel_unneed_metadata(void) 310 { 311 static_key_slow_dec(&ip_tunnel_metadata_cnt); 312 } 313 EXPORT_SYMBOL_GPL(ip_tunnel_unneed_metadata); 314