1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _NF_QUEUE_H 3#define _NF_QUEUE_H 4 5#include <linux/ip.h> 6#include <linux/ipv6.h> 7#include <linux/jhash.h> 8#include <linux/netfilter.h> 9#include <linux/skbuff.h> 10 11/* Each queued (to userspace) skbuff has one of these. */ 12struct nf_queue_entry { 13 struct list_head list; 14 struct sk_buff *skb; 15 unsigned int id; 16 unsigned int hook_index; /* index in hook_entries->hook[] */ 17#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) 18 struct net_device *physin; 19 struct net_device *physout; 20#endif 21 struct nf_hook_state state; 22 u16 size; /* sizeof(entry) + saved route keys */ 23 24 /* extra space to store route keys */ 25}; 26 27#define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry)) 28 29/* Packet queuing */ 30struct nf_queue_handler { 31 int (*outfn)(struct nf_queue_entry *entry, 32 unsigned int queuenum); 33 void (*nf_hook_drop)(struct net *net); 34}; 35 36void nf_register_queue_handler(const struct nf_queue_handler *qh); 37void nf_unregister_queue_handler(void); 38 39bool nf_queue_entry_get_refs(struct nf_queue_entry *entry); 40void nf_queue_entry_free(struct nf_queue_entry *entry); 41 42static inline void init_hashrandom(u32 *jhash_initval) 43{ 44 while (*jhash_initval == 0) 45 *jhash_initval = get_random_u32(); 46} 47 48static inline u32 hash_v4(const struct iphdr *iph, u32 initval) 49{ 50 /* packets in either direction go into same queue */ 51 if ((__force u32)iph->saddr < (__force u32)iph->daddr) 52 return jhash_3words((__force u32)iph->saddr, 53 (__force u32)iph->daddr, iph->protocol, initval); 54 55 return jhash_3words((__force u32)iph->daddr, 56 (__force u32)iph->saddr, iph->protocol, initval); 57} 58 59static inline u32 hash_v6(const struct ipv6hdr *ip6h, u32 initval) 60{ 61 u32 a, b, c; 62 63 if ((__force u32)ip6h->saddr.s6_addr32[3] < 64 (__force u32)ip6h->daddr.s6_addr32[3]) { 65 a = (__force u32) ip6h->saddr.s6_addr32[3]; 66 b = (__force u32) ip6h->daddr.s6_addr32[3]; 67 } else { 68 b = (__force u32) ip6h->saddr.s6_addr32[3]; 69 a = (__force u32) ip6h->daddr.s6_addr32[3]; 70 } 71 72 if ((__force u32)ip6h->saddr.s6_addr32[1] < 73 (__force u32)ip6h->daddr.s6_addr32[1]) 74 c = (__force u32) ip6h->saddr.s6_addr32[1]; 75 else 76 c = (__force u32) ip6h->daddr.s6_addr32[1]; 77 78 return jhash_3words(a, b, c, initval); 79} 80 81static inline u32 hash_bridge(const struct sk_buff *skb, u32 initval) 82{ 83 struct ipv6hdr *ip6h, _ip6h; 84 struct iphdr *iph, _iph; 85 86 switch (eth_hdr(skb)->h_proto) { 87 case htons(ETH_P_IP): 88 iph = skb_header_pointer(skb, skb_network_offset(skb), 89 sizeof(*iph), &_iph); 90 if (iph) 91 return hash_v4(iph, initval); 92 break; 93 case htons(ETH_P_IPV6): 94 ip6h = skb_header_pointer(skb, skb_network_offset(skb), 95 sizeof(*ip6h), &_ip6h); 96 if (ip6h) 97 return hash_v6(ip6h, initval); 98 break; 99 } 100 101 return 0; 102} 103 104static inline u32 105nfqueue_hash(const struct sk_buff *skb, u16 queue, u16 queues_total, u8 family, 106 u32 initval) 107{ 108 switch (family) { 109 case NFPROTO_IPV4: 110 queue += reciprocal_scale(hash_v4(ip_hdr(skb), initval), 111 queues_total); 112 break; 113 case NFPROTO_IPV6: 114 queue += reciprocal_scale(hash_v6(ipv6_hdr(skb), initval), 115 queues_total); 116 break; 117 case NFPROTO_BRIDGE: 118 queue += reciprocal_scale(hash_bridge(skb, initval), 119 queues_total); 120 break; 121 } 122 123 return queue; 124} 125 126int nf_queue(struct sk_buff *skb, struct nf_hook_state *state, 127 unsigned int index, unsigned int verdict); 128 129#endif /* _NF_QUEUE_H */ 130