/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _NF_QUEUE_H
#define _NF_QUEUE_H
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/jhash.h>
#include <linux/netfilter.h>
#include <linux/skbuff.h>
/* Each queued (to userspace) skbuff has one of these. */
struct nf_queue_entry {
struct list_head list;
struct sk_buff *skb;
unsigned int id;
unsigned int hook_index; /* index in hook_entries->hook[] */
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
struct net_device *physin;
struct net_device *physout;
#endif
struct nf_hook_state state;
u16 size; /* sizeof(entry) + saved route keys */
/* extra space to store route keys */
};
#define nf_queue_entry_reroute(x) ((void *)x + sizeof(struct nf_queue_entry))
/* Packet queuing */
struct nf_queue_handler {
int (*outfn)(struct nf_queue_entry *entry,
unsigned int queuenum);
void (*nf_hook_drop)(struct net *net);
};
void nf_register_queue_handler(const struct nf_queue_handler *qh);
void nf_unregister_queue_handler(void);
bool nf_queue_entry_get_refs(struct nf_queue_entry *entry);
void nf_queue_entry_free(struct nf_queue_entry *entry);
static inline void init_hashrandom(u32 *jhash_initval)
{
while (*jhash_initval == 0)
*jhash_initval = get_random_u32();
}
static inline u32 hash_v4(const struct iphdr *iph, u32 initval)
{
/* packets in either direction go into same queue */
if ((__force u32)iph->saddr < (__force u32)iph->daddr)
return jhash_3words((__force u32)iph->saddr,
(__force u32)iph->daddr, iph->protocol, initval);
return jhash_3words((__force u32)iph->daddr,
(__force u32)iph->saddr, iph->protocol, initval);
}
static inline u32 hash_v6(const struct ipv6hdr *ip6h, u32 initval)
{
u32 a, b, c;
if ((__force u32)ip6h->saddr.s6_addr32[3] <
(__force u32)ip6h->daddr.s6_addr32[3]) {
a = (__force u32) ip6h->saddr.s6_addr32[3];
b = (__force u32) ip6h->daddr.s6_addr32[3];
} else {
b = (__force u32) ip6h->saddr.s6_addr32[3];
a = (__force u32) ip6h->daddr.s6_addr32[3];
}
if ((__force u32)ip6h->saddr.s6_addr32[1] <
(__force u32)ip6h->daddr.s6_addr32[1])
c = (__force u32) ip6h->saddr.s6_addr32[1];
else
c = (__force u32) ip6h->daddr.s6_addr32[1];
return jhash_3words(a, b, c, initval);
}
static inline u32 hash_bridge(const struct sk_buff *skb, u32 initval)
{
struct ipv6hdr *ip6h, _ip6h;
struct iphdr *iph, _iph;
switch (eth_hdr(skb)->h_proto) {
case htons(ETH_P_IP):
iph = skb_header_pointer(skb, skb_network_offset(skb),
sizeof(*iph), &_iph);
if (iph)
return hash_v4(iph, initval);
break;
case htons(ETH_P_IPV6):
ip6h = skb_header_pointer(skb, skb_network_offset(skb),
sizeof(*ip6h), &_ip6h);
if (ip6h)
return hash_v6(ip6h, initval);
break;
}
return 0;
}
static inline u32
nfqueue_hash(const struct sk_buff *skb, u16 queue, u16 queues_total, u8 family,
u32 initval)
{
switch (family) {
case NFPROTO_IPV4:
queue += reciprocal_scale(hash_v4(ip_hdr(skb), initval),
queues_total);
break;
case NFPROTO_IPV6:
queue += reciprocal_scale(hash_v6(ipv6_hdr(skb), initval),
queues_total);
break;
case NFPROTO_BRIDGE:
queue += reciprocal_scale(hash_bridge(skb, initval),
queues_total);
break;
}
return queue;
}
int nf_queue(struct sk_buff *skb, struct nf_hook_state *state,
unsigned int index, unsigned int verdict);
#endif /* _NF_QUEUE_H */