1 #ifndef __NET_IP_WRAPPER_H
2 #define __NET_IP_WRAPPER_H 1
4 #include_next <net/ip.h>
7 #include <linux/version.h>
9 #ifndef HAVE_IP_IS_FRAGMENT
10 static inline bool ip_is_fragment(const struct iphdr *iph)
12 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
16 #ifndef HAVE_INET_GET_LOCAL_PORT_RANGE_USING_NET
17 static inline void rpl_inet_get_local_port_range(struct net *net, int *low,
20 inet_get_local_port_range(low, high);
22 #define inet_get_local_port_range rpl_inet_get_local_port_range
26 #ifndef IPSKB_FRAG_PMTU
27 #define IPSKB_FRAG_PMTU BIT(6)
30 /* IPv4 datagram length is stored into 16bit field (tot_len) */
32 #define IP_MAX_MTU 0xFFFFU
35 #ifndef HAVE_IP_SKB_DST_MTU
36 static inline bool rpl_ip_sk_use_pmtu(const struct sock *sk)
38 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE;
40 #define ip_sk_use_pmtu rpl_ip_sk_use_pmtu
42 static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst,
45 #if LINUX_VERSION_CODE >= KERNEL_VERSION(3,14,0)
46 struct net *net = dev_net(dst->dev);
48 if (net->ipv4.sysctl_ip_fwd_use_pmtu ||
49 dst_metric_locked(dst, RTAX_MTU) ||
54 return min(dst->dev->mtu, IP_MAX_MTU);
57 static inline unsigned int rpl_ip_skb_dst_mtu(const struct sk_buff *skb)
59 if (!skb->sk || ip_sk_use_pmtu(skb->sk)) {
60 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED;
61 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding);
63 return min(skb_dst(skb)->dev->mtu, IP_MAX_MTU);
66 #define ip_skb_dst_mtu rpl_ip_skb_dst_mtu
67 #endif /* HAVE_IP_SKB_DST_MTU */
69 #ifdef HAVE_IP_FRAGMENT_TAKES_SOCK
70 #define OVS_VPORT_OUTPUT_PARAMS struct sock *sock, struct sk_buff *skb
72 #define OVS_VPORT_OUTPUT_PARAMS struct sk_buff *skb
75 #ifdef OVS_FRAGMENT_BACKPORT
77 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
78 static inline bool ip_defrag_user_in_between(u32 user,
79 enum ip_defrag_users lower_bond,
80 enum ip_defrag_users upper_bond)
82 return user >= lower_bond && user <= upper_bond;
86 #ifndef HAVE_IP_DO_FRAGMENT
87 static inline int rpl_ip_do_fragment(struct sock *sk, struct sk_buff *skb,
88 int (*output)(OVS_VPORT_OUTPUT_PARAMS))
90 unsigned int mtu = ip_skb_dst_mtu(skb);
91 struct iphdr *iph = ip_hdr(skb);
92 struct rtable *rt = skb_rtable(skb);
93 struct net_device *dev = rt->dst.dev;
95 if (unlikely(((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) ||
96 (IPCB(skb)->frag_max_size &&
97 IPCB(skb)->frag_max_size > mtu))) {
99 pr_warn("Dropping packet in ip_do_fragment()\n");
100 IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS);
105 #ifndef HAVE_IP_FRAGMENT_TAKES_SOCK
106 return ip_fragment(skb, output);
108 return ip_fragment(sk, skb, output);
111 #define ip_do_fragment rpl_ip_do_fragment
112 #endif /* IP_DO_FRAGMENT */
114 /* Prior to upstream commit d6b915e29f4a ("ip_fragment: don't forward
115 * defragmented DF packet"), IPCB(skb)->frag_max_size was not always populated
116 * correctly, which would lead to reassembled packets not being refragmented.
117 * So, we backport all of ip_defrag() in these cases.
119 int rpl_ip_defrag(struct sk_buff *skb, u32 user);
120 #define ip_defrag rpl_ip_defrag
122 int __init rpl_ipfrag_init(void);
123 void rpl_ipfrag_fini(void);
124 #else /* OVS_FRAGMENT_BACKPORT */
126 /* We have no good way to detect the presence of upstream commit 8282f27449bf
127 * ("inet: frag: Always orphan skbs inside ip_defrag()"), but it should be
128 * always included in kernels 4.5+. */
129 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,5,0)
130 static inline int rpl_ip_defrag(struct sk_buff *skb, u32 user)
133 return ip_defrag(skb, user);
135 #define ip_defrag rpl_ip_defrag
138 static inline int rpl_ipfrag_init(void) { return 0; }
139 static inline void rpl_ipfrag_fini(void) { }
140 #endif /* OVS_FRAGMENT_BACKPORT */
141 #define ipfrag_init rpl_ipfrag_init
142 #define ipfrag_fini rpl_ipfrag_fini