1 #ifndef _NF_QUEUE_H
2 #define _NF_QUEUE_H
3
4 #include <linux/ip.h>
5 #include <linux/ipv6.h>
6 #include <linux/jhash.h>
7
8 /* Each queued (to userspace) skbuff has one of these. */
9 struct nf_queue_entry {
10 struct list_head list;
11 struct sk_buff *skb;
12 unsigned int id;
13
14 struct nf_hook_ops *elem;
15 u_int8_t pf;
16 u16 size; /* sizeof(entry) + saved route keys */
17 unsigned int hook;
18 struct net_device *indev;
19 struct net_device *outdev;
20 int (*okfn)(struct sk_buff *);
21
22 /* extra space to store route keys */
23 };
24
25 #define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry))
26
27 /* Packet queuing */
28 struct nf_queue_handler {
29 int (*outfn)(struct nf_queue_entry *entry,
30 unsigned int queuenum);
31 void (*nf_hook_drop)(struct net *net,
32 struct nf_hook_ops *ops);
33 };
34
35 void nf_register_queue_handler(const struct nf_queue_handler *qh);
36 void nf_unregister_queue_handler(void);
37 void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict);
38
39 bool nf_queue_entry_get_refs(struct nf_queue_entry *entry);
40 void nf_queue_entry_release_refs(struct nf_queue_entry *entry);
41
init_hashrandom(u32 * jhash_initval)42 static inline void init_hashrandom(u32 *jhash_initval)
43 {
44 while (*jhash_initval == 0)
45 *jhash_initval = prandom_u32();
46 }
47
hash_v4(const struct sk_buff * skb,u32 jhash_initval)48 static inline u32 hash_v4(const struct sk_buff *skb, u32 jhash_initval)
49 {
50 const struct iphdr *iph = ip_hdr(skb);
51
52 /* packets in either direction go into same queue */
53 if ((__force u32)iph->saddr < (__force u32)iph->daddr)
54 return jhash_3words((__force u32)iph->saddr,
55 (__force u32)iph->daddr, iph->protocol, jhash_initval);
56
57 return jhash_3words((__force u32)iph->daddr,
58 (__force u32)iph->saddr, iph->protocol, jhash_initval);
59 }
60
61 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
hash_v6(const struct sk_buff * skb,u32 jhash_initval)62 static inline u32 hash_v6(const struct sk_buff *skb, u32 jhash_initval)
63 {
64 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
65 u32 a, b, c;
66
67 if ((__force u32)ip6h->saddr.s6_addr32[3] <
68 (__force u32)ip6h->daddr.s6_addr32[3]) {
69 a = (__force u32) ip6h->saddr.s6_addr32[3];
70 b = (__force u32) ip6h->daddr.s6_addr32[3];
71 } else {
72 b = (__force u32) ip6h->saddr.s6_addr32[3];
73 a = (__force u32) ip6h->daddr.s6_addr32[3];
74 }
75
76 if ((__force u32)ip6h->saddr.s6_addr32[1] <
77 (__force u32)ip6h->daddr.s6_addr32[1])
78 c = (__force u32) ip6h->saddr.s6_addr32[1];
79 else
80 c = (__force u32) ip6h->daddr.s6_addr32[1];
81
82 return jhash_3words(a, b, c, jhash_initval);
83 }
84 #endif
85
86 static inline u32
nfqueue_hash(const struct sk_buff * skb,u16 queue,u16 queues_total,u8 family,u32 jhash_initval)87 nfqueue_hash(const struct sk_buff *skb, u16 queue, u16 queues_total, u8 family,
88 u32 jhash_initval)
89 {
90 if (family == NFPROTO_IPV4)
91 queue += ((u64) hash_v4(skb, jhash_initval) * queues_total) >> 32;
92 #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
93 else if (family == NFPROTO_IPV6)
94 queue += ((u64) hash_v6(skb, jhash_initval) * queues_total) >> 32;
95 #endif
96
97 return queue;
98 }
99
100 #endif /* _NF_QUEUE_H */
101