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 36 #include <net/ip.h> 37 #include <net/icmp.h> 38 #include <net/protocol.h> 39 #include <net/ip_tunnels.h> 40 #include <net/arp.h> 41 #include <net/checksum.h> 42 #include <net/dsfield.h> 43 #include <net/inet_ecn.h> 44 #include <net/xfrm.h> 45 #include <net/net_namespace.h> 46 #include <net/netns/generic.h> 47 #include <net/rtnetlink.h> 48 49 int iptunnel_xmit(struct rtable *rt, struct sk_buff *skb, 50 __be32 src, __be32 dst, __u8 proto, 51 __u8 tos, __u8 ttl, __be16 df, bool xnet) 52 { 53 int pkt_len = skb->len; 54 struct iphdr *iph; 55 int err; 56 57 skb_scrub_packet(skb, xnet); 58 59 skb->rxhash = 0; 60 skb_dst_set(skb, &rt->dst); 61 memset(IPCB(skb), 0, sizeof(*IPCB(skb))); 62 63 /* Push down and install the IP header. */ 64 skb_push(skb, sizeof(struct iphdr)); 65 skb_reset_network_header(skb); 66 67 iph = ip_hdr(skb); 68 69 iph->version = 4; 70 iph->ihl = sizeof(struct iphdr) >> 2; 71 iph->frag_off = df; 72 iph->protocol = proto; 73 iph->tos = tos; 74 iph->daddr = dst; 75 iph->saddr = src; 76 iph->ttl = ttl; 77 __ip_select_ident(iph, &rt->dst, (skb_shinfo(skb)->gso_segs ?: 1) - 1); 78 79 err = ip_local_out(skb); 80 if (unlikely(net_xmit_eval(err))) 81 pkt_len = 0; 82 return pkt_len; 83 } 84 EXPORT_SYMBOL_GPL(iptunnel_xmit); 85 86 int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto) 87 { 88 if (unlikely(!pskb_may_pull(skb, hdr_len))) 89 return -ENOMEM; 90 91 skb_pull_rcsum(skb, hdr_len); 92 93 if (inner_proto == htons(ETH_P_TEB)) { 94 struct ethhdr *eh = (struct ethhdr *)skb->data; 95 96 if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) 97 return -ENOMEM; 98 99 if (likely(ntohs(eh->h_proto) >= ETH_P_802_3_MIN)) 100 skb->protocol = eh->h_proto; 101 else 102 skb->protocol = htons(ETH_P_802_2); 103 104 } else { 105 skb->protocol = inner_proto; 106 } 107 108 nf_reset(skb); 109 secpath_reset(skb); 110 if (!skb->l4_rxhash) 111 skb->rxhash = 0; 112 skb_dst_drop(skb); 113 skb->vlan_tci = 0; 114 skb_set_queue_mapping(skb, 0); 115 skb->pkt_type = PACKET_HOST; 116 return 0; 117 } 118 EXPORT_SYMBOL_GPL(iptunnel_pull_header); 119 120 struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, 121 bool csum_help, 122 int gso_type_mask) 123 { 124 int err; 125 126 if (likely(!skb->encapsulation)) { 127 skb_reset_inner_headers(skb); 128 skb->encapsulation = 1; 129 } 130 131 if (skb_is_gso(skb)) { 132 err = skb_unclone(skb, GFP_ATOMIC); 133 if (unlikely(err)) 134 goto error; 135 skb_shinfo(skb)->gso_type |= gso_type_mask; 136 return skb; 137 } 138 139 if (skb->ip_summed == CHECKSUM_PARTIAL && csum_help) { 140 err = skb_checksum_help(skb); 141 if (unlikely(err)) 142 goto error; 143 } else if (skb->ip_summed != CHECKSUM_PARTIAL) 144 skb->ip_summed = CHECKSUM_NONE; 145 146 return skb; 147 error: 148 kfree_skb(skb); 149 return ERR_PTR(err); 150 } 151 EXPORT_SYMBOL_GPL(iptunnel_handle_offloads); 152