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/usr/src/kernels/4.18.0-553.157.1.el8_10.x86_64/include/net/

/usr/src/kernels/4.18.0-553.157.1.el8_10.x86_64/include/net

Name	Size	Mode	Actions
9p/	-	0755	rm
bluetooth/	-	0755	rm
caif/	-	0755	rm
iucv/	-	0755	rm
mana/	-	0755	rm
netfilter/	-	0755	rm
netns/	-	0755	rm
nfc/	-	0755	rm
phonet/	-	0755	rm
sctp/	-	0755	rm
tc_act/	-	0755	rm
6lowpan.h	10271	0644	edit dl rm
act_api.h	9559	0644	edit dl rm
addrconf.h	13826	0644	edit dl rm
af_ieee802154.h	1591	0644	edit dl rm
af_rxrpc.h	2976	0644	edit dl rm
af_unix.h	2272	0644	edit dl rm
af_vsock.h	7295	0644	edit dl rm
ah.h	382	0644	edit dl rm
arp.h	2052	0644	edit dl rm
atmclip.h	1515	0644	edit dl rm
ax25.h	14999	0644	edit dl rm
ax88796.h	1488	0644	edit dl rm
bareudp.h	333	0644	edit dl rm
bonding.h	20225	0644	edit dl rm
bond_3ad.h	9629	0644	edit dl rm
bond_alb.h	6251	0644	edit dl rm
bond_options.h	3916	0644	edit dl rm
bpf_sk_storage.h	1802	0644	edit dl rm
busy_poll.h	4973	0644	edit dl rm
calipso.h	2199	0644	edit dl rm
cfg80211-wext.h	1900	0644	edit dl rm
cfg80211.h	325844	0644	edit dl rm
cfg802154.h	11175	0644	edit dl rm
checksum.h	4850	0644	edit dl rm
cipso_ipv4.h	8399	0644	edit dl rm
cls_cgroup.h	2301	0644	edit dl rm
codel.h	6000	0644	edit dl rm
codel_impl.h	8500	0644	edit dl rm
codel_qdisc.h	3001	0644	edit dl rm
compat.h	1711	0644	edit dl rm
datalink.h	619	0644	edit dl rm
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dn_route.h	4500	0644	edit dl rm
dropreason-core.h	12063	0644	edit dl rm
drop_monitor.h	901	0644	edit dl rm
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dsfield.h	1139	0644	edit dl rm
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dst_cache.h	2596	0644	edit dl rm
dst_metadata.h	5521	0644	edit dl rm
dst_ops.h	2564	0644	edit dl rm
erspan.h	8527	0644	edit dl rm
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espintcp.h	966	0644	edit dl rm
ethoc.h	537	0644	edit dl rm
failover.h	1178	0644	edit dl rm
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fib_rules.h	5728	0644	edit dl rm
firewire.h	636	0644	edit dl rm
flow.h	6353	0644	edit dl rm
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garp.h	2678	0644	edit dl rm
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gen_stats.h	3034	0644	edit dl rm
gre.h	3377	0644	edit dl rm
gro_cells.h	443	0644	edit dl rm
gtp.h	633	0644	edit dl rm
gue.h	3311	0644	edit dl rm
hwbm.h	937	0644	edit dl rm
icmp.h	1765	0644	edit dl rm
ieee80211_radiotap.h	23017	0644	edit dl rm
ieee802154_netdev.h	9358	0644	edit dl rm
ife.h	1057	0644	edit dl rm
if_inet6.h	6591	0644	edit dl rm
ila.h	498	0644	edit dl rm
inet6_connection_sock.h	976	0644	edit dl rm
inet6_hashtables.h	3746	0644	edit dl rm
inetpeer.h	3372	0644	edit dl rm
inet_common.h	2614	0644	edit dl rm
inet_connection_sock.h	12070	0644	edit dl rm
inet_ecn.h	8071	0644	edit dl rm
inet_frag.h	4816	0644	edit dl rm
inet_hashtables.h	13847	0644	edit dl rm
inet_sock.h	9828	0644	edit dl rm
inet_timewait_sock.h	3926	0644	edit dl rm
ip.h	21354	0644	edit dl rm
ip6_checksum.h	2981	0644	edit dl rm
ip6_fib.h	13766	0644	edit dl rm
ip6_route.h	9228	0644	edit dl rm
ip6_tunnel.h	5096	0644	edit dl rm
ipcomp.h	659	0644	edit dl rm
ipconfig.h	811	0644	edit dl rm
ipv6.h	32741	0644	edit dl rm
ipv6_frag.h	3321	0644	edit dl rm
ipv6_stubs.h	2671	0644	edit dl rm
ipx.h	4386	0644	edit dl rm
ip_fib.h	14290	0644	edit dl rm
ip_tunnels.h	14697	0644	edit dl rm
ip_vs.h	49407	0644	edit dl rm
iw_handler.h	21413	0644	edit dl rm
kcm.h	5083	0644	edit dl rm
l3mdev.h	6743	0644	edit dl rm
lag.h	409	0644	edit dl rm
lapb.h	4869	0644	edit dl rm
lib80211.h	4017	0644	edit dl rm
llc.h	4464	0644	edit dl rm
llc_conn.h	4155	0644	edit dl rm
llc_c_ac.h	9537	0644	edit dl rm
llc_c_ev.h	10940	0644	edit dl rm
llc_c_st.h	1762	0644	edit dl rm
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lwtunnel.h	6563	0644	edit dl rm
mac80211.h	294437	0644	edit dl rm
mac802154.h	15633	0644	edit dl rm
mip6.h	1617	0644	edit dl rm
mld.h	2870	0644	edit dl rm
mpls.h	1340	0644	edit dl rm
mpls_iptunnel.h	827	0644	edit dl rm
mptcp.h	6242	0644	edit dl rm
mrp.h	3103	0644	edit dl rm
ncsi.h	1964	0644	edit dl rm
ndisc.h	15095	0644	edit dl rm
neighbour.h	16289	0644	edit dl rm
netdev_queues.h	5609	0644	edit dl rm
netevent.h	1044	0644	edit dl rm
netlabel.h	21236	0644	edit dl rm
netlink.h	63253	0644	edit dl rm
netprio_cgroup.h	1260	0644	edit dl rm
netrom.h	7896	0644	edit dl rm
net_failover.h	1023	0644	edit dl rm
net_namespace.h	14177	0644	edit dl rm
net_ratelimit.h	220	0644	edit dl rm
nexthop.h	865	0644	edit dl rm
nl802154.h	12385	0644	edit dl rm
nsh.h	12602	0644	edit dl rm
p8022.h	447	0644	edit dl rm
page_pool.h	6985	0644	edit dl rm
pie.h	3684	0644	edit dl rm
ping.h	3197	0644	edit dl rm
pkt_cls.h	26178	0644	edit dl rm
pkt_sched.h	6543	0644	edit dl rm
pptp.h	557	0644	edit dl rm
protocol.h	4320	0644	edit dl rm
psample.h	1083	0644	edit dl rm
psnap.h	351	0644	edit dl rm
raw.h	2161	0644	edit dl rm
rawv6.h	856	0644	edit dl rm
red.h	11600	0644	edit dl rm
regulatory.h	10961	0644	edit dl rm
request_sock.h	6871	0644	edit dl rm
rose.h	7802	0644	edit dl rm
route.h	11390	0644	edit dl rm
rsi_91x.h	1710	0644	edit dl rm
rtnetlink.h	7317	0644	edit dl rm
sch_generic.h	33841	0644	edit dl rm
scm.h	3671	0644	edit dl rm
secure_seq.h	855	0644	edit dl rm
seg6.h	1874	0644	edit dl rm
seg6_hmac.h	1699	0644	edit dl rm
seg6_local.h	870	0644	edit dl rm
slhc_vj.h	6831	0644	edit dl rm
smc.h	2155	0644	edit dl rm
snmp.h	5482	0644	edit dl rm
sock.h	79182	0644	edit dl rm
sock_reuseport.h	1565	0644	edit dl rm
Space.h	1094	0644	edit dl rm
stp.h	383	0644	edit dl rm
strparser.h	4340	0644	edit dl rm
switchdev.h	17812	0644	edit dl rm
tcp.h	73206	0644	edit dl rm
tcp_states.h	1540	0644	edit dl rm
tc_wrapper.h	7033	0644	edit dl rm
timewait_sock.h	1136	0644	edit dl rm
tipc.h	2405	0644	edit dl rm
tls.h	21363	0644	edit dl rm
tls_toe.h	3006	0644	edit dl rm
transp_v6.h	1996	0644	edit dl rm
tso.h	515	0644	edit dl rm
tun_proto.h	988	0644	edit dl rm
udp.h	16481	0644	edit dl rm
udplite.h	3762	0644	edit dl rm
udp_tunnel.h	13376	0644	edit dl rm
vsock_addr.h	662	0644	edit dl rm
vxlan.h	13541	0644	edit dl rm
wext.h	1510	0644	edit dl rm
wimax.h	20445	0644	edit dl rm
x25.h	9658	0644	edit dl rm
x25device.h	387	0644	edit dl rm
xdp.h	9436	0644	edit dl rm
xdp_priv.h	446	0644	edit dl rm
xdp_sock.h	2094	0644	edit dl rm
xdp_sock_drv.h	6423	0644	edit dl rm
xfrm.h	59628	0644	edit dl rm
xsk_buff_pool.h	6550	0644	edit dl rm

Edit: /usr/src/kernels/4.18.0-553.157.1.el8_10.x86_64/include/net/udp.h (16481B)

/*
 * INET		An implementation of the TCP/IP protocol suite for the LINUX
 *		operating system.  INET is implemented using the  BSD Socket
 *		interface as the means of communication with the user level.
 *
 *		Definitions for the UDP module.
 *
 * Version:	@(#)udp.h	1.0.2	05/07/93
 *
 * Authors:	Ross Biro
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *
 * Fixes:
 *		Alan Cox	: Turned on udp checksums. I don't want to
 *				  chase 'memory corruption' bugs that aren't!
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 */
#ifndef _UDP_H
#define _UDP_H

#include <linux/list.h>
#include <linux/bug.h>
#include <net/inet_sock.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ip.h>
#include <linux/ipv6.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
#include <linux/indirect_call_wrapper.h>

/**
 *	struct udp_skb_cb  -  UDP(-Lite) private variables
 *
 *	@header:      private variables used by IPv4/IPv6
 *	@cscov:       checksum coverage length (UDP-Lite only)
 *	@partial_cov: if set indicates partial csum coverage
 */
struct udp_skb_cb {
	union {
		struct inet_skb_parm	h4;
#if IS_ENABLED(CONFIG_IPV6)
		struct inet6_skb_parm	h6;
#endif
	} header;
	__u16		cscov;
	__u8		partial_cov;
};
#define UDP_SKB_CB(__skb)	((struct udp_skb_cb *)((__skb)->cb))

/**
 *	struct udp_hslot - UDP hash slot
 *
 *	@head:	head of list of sockets
 *	@count:	number of sockets in 'head' list
 *	@lock:	spinlock protecting changes to head/count
 */
struct udp_hslot {
	struct hlist_head	head;
	int			count;
	spinlock_t		lock;
} __attribute__((aligned(2 * sizeof(long))));

/**
 *	struct udp_table - UDP table
 *
 *	@hash:	hash table, sockets are hashed on (local port)
 *	@hash2:	hash table, sockets are hashed on (local port, local address)
 *	@mask:	number of slots in hash tables, minus 1
 *	@log:	log2(number of slots in hash table)
 */
struct udp_table {
	struct udp_hslot	*hash;
	struct udp_hslot	*hash2;
	unsigned int		mask;
	unsigned int		log;
};
extern struct udp_table udp_table;
void udp_table_init(struct udp_table *, const char *);
static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
					     struct net *net, unsigned int num)
{
	return &table->hash[udp_hashfn(net, num, table->mask)];
}
/*
 * For secondary hash, net_hash_mix() is performed before calling
 * udp_hashslot2(), this explains difference with udp_hashslot()
 */
static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
					      unsigned int hash)
{
	return &table->hash2[hash & table->mask];
}

extern struct proto udp_prot;

extern atomic_long_t udp_memory_allocated;

/* sysctl variables for udp */
extern long sysctl_udp_mem[3];
extern int sysctl_udp_rmem_min;
extern int sysctl_udp_wmem_min;

struct sk_buff;

/*
 *	Generic checksumming routines for UDP(-Lite) v4 and v6
 */
static inline __sum16 __udp_lib_checksum_complete(struct sk_buff *skb)
{
	return (UDP_SKB_CB(skb)->cscov == skb->len ?
		__skb_checksum_complete(skb) :
		__skb_checksum_complete_head(skb, UDP_SKB_CB(skb)->cscov));
}

static inline int udp_lib_checksum_complete(struct sk_buff *skb)
{
	return !skb_csum_unnecessary(skb) &&
		__udp_lib_checksum_complete(skb);
}

/**
 * 	udp_csum_outgoing  -  compute UDPv4/v6 checksum over fragments
 * 	@sk: 	socket we are writing to
 * 	@skb: 	sk_buff containing the filled-in UDP header
 * 	        (checksum field must be zeroed out)
 */
static inline __wsum udp_csum_outgoing(struct sock *sk, struct sk_buff *skb)
{
	__wsum csum = csum_partial(skb_transport_header(skb),
				   sizeof(struct udphdr), 0);
	skb_queue_walk(&sk->sk_write_queue, skb) {
		csum = csum_add(csum, skb->csum);
	}
	return csum;
}

static inline __wsum udp_csum(struct sk_buff *skb)
{
	__wsum csum = csum_partial(skb_transport_header(skb),
				   sizeof(struct udphdr), skb->csum);

for (skb = skb_shinfo(skb)->frag_list; skb; skb = skb->next) {
		csum = csum_add(csum, skb->csum);
	}
	return csum;
}

static inline __sum16 udp_v4_check(int len, __be32 saddr,
				   __be32 daddr, __wsum base)
{
	return csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base);
}

void udp_set_csum(bool nocheck, struct sk_buff *skb,
		  __be32 saddr, __be32 daddr, int len);

static inline void udp_csum_pull_header(struct sk_buff *skb)
{
	if (!skb->csum_valid && skb->ip_summed == CHECKSUM_NONE)
		skb->csum = csum_partial(skb->data, sizeof(struct udphdr),
					 skb->csum);
	skb_pull_rcsum(skb, sizeof(struct udphdr));
	UDP_SKB_CB(skb)->cscov -= sizeof(struct udphdr);
}

typedef struct sock *(*udp_lookup_t)(const struct sk_buff *skb, __be16 sport,
				     __be16 dport);

INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
							   struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp6_gro_receive(struct list_head *,
							   struct sk_buff *));
INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
struct sk_buff *udp_gro_receive(struct list_head *head, struct sk_buff *skb,
				struct udphdr *uh, struct sock *sk);
int udp_gro_complete(struct sk_buff *skb, int nhoff, udp_lookup_t lookup);

struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
				  netdev_features_t features, bool is_ipv6);

static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
{
	struct udphdr *uh;
	unsigned int hlen, off;

off  = skb_gro_offset(skb);
	hlen = off + sizeof(*uh);
	uh   = skb_gro_header_fast(skb, off);
	if (skb_gro_header_hard(skb, hlen))
		uh = skb_gro_header_slow(skb, hlen, off);

return uh;
}

/* hash routines shared between UDPv4/6 and UDP-Litev4/6 */
static inline int udp_lib_hash(struct sock *sk)
{
	BUG();
	return 0;
}

void udp_lib_unhash(struct sock *sk);
void udp_lib_rehash(struct sock *sk, u16 new_hash);

static inline void udp_lib_close(struct sock *sk, long timeout)
{
	sk_common_release(sk);
}

int udp_lib_get_port(struct sock *sk, unsigned short snum,
		     unsigned int hash2_nulladdr);

u32 udp_flow_hashrnd(void);

static inline __be16 udp_flow_src_port(struct net *net, struct sk_buff *skb,
				       int min, int max, bool use_eth)
{
	u32 hash;

if (min >= max) {
		/* Use default range */
		inet_get_local_port_range(net, &min, &max);
	}

hash = skb_get_hash(skb);
	if (unlikely(!hash)) {
		if (use_eth) {
			/* Can't find a normal hash, caller has indicated an
			 * Ethernet packet so use that to compute a hash.
			 */
			hash = jhash(skb->data, 2 * ETH_ALEN,
				     (__force u32) skb->protocol);
		} else {
			/* Can't derive any sort of hash for the packet, set
			 * to some consistent random value.
			 */
			hash = udp_flow_hashrnd();
		}
	}

/* Since this is being sent on the wire obfuscate hash a bit
	 * to minimize possbility that any useful information to an
	 * attacker is leaked. Only upper 16 bits are relevant in the
	 * computation for 16 bit port value.
	 */
	hash ^= hash << 16;

return htons((((u64) hash * (max - min)) >> 32) + min);
}

static inline int udp_rqueue_get(struct sock *sk)
{
	return sk_rmem_alloc_get(sk) - READ_ONCE(udp_sk(sk)->forward_deficit);
}

static inline bool udp_sk_bound_dev_eq(struct net *net, int bound_dev_if,
				       int dif, int sdif)
{
#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
	return inet_bound_dev_eq(!!READ_ONCE(net->ipv4.sysctl_udp_l3mdev_accept),
				 bound_dev_if, dif, sdif);
#else
	return inet_bound_dev_eq(true, bound_dev_if, dif, sdif);
#endif
}

/* net/ipv4/udp.c */
void udp_destruct_common(struct sock *sk);
void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len);
int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb);
void udp_skb_destructor(struct sock *sk, struct sk_buff *skb);
struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
			       int noblock, int *off, int *err);
static inline struct sk_buff *skb_recv_udp(struct sock *sk, unsigned int flags,
					   int noblock, int *err)
{
	int off = 0;

return __skb_recv_udp(sk, flags, noblock, &off, err);
}

int udp_v4_early_demux(struct sk_buff *skb);
bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst);
int udp_get_port(struct sock *sk, unsigned short snum,
		 int (*saddr_cmp)(const struct sock *,
				  const struct sock *));
int udp_err(struct sk_buff *, u32);
int udp_abort(struct sock *sk, int err);
int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len);
int udp_push_pending_frames(struct sock *sk);
void udp_flush_pending_frames(struct sock *sk);
int udp_cmsg_send(struct sock *sk, struct msghdr *msg, u16 *gso_size);
void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst);
int udp_rcv(struct sk_buff *skb);
int udp_ioctl(struct sock *sk, int cmd, unsigned long arg);
int udp_init_sock(struct sock *sk);
int udp_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);
int __udp_disconnect(struct sock *sk, int flags);
int udp_disconnect(struct sock *sk, int flags);
__poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait);
struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
				       netdev_features_t features,
				       bool is_ipv6);
int udp_lib_getsockopt(struct sock *sk, int level, int optname,
		       char __user *optval, int __user *optlen);
int udp_lib_setsockopt(struct sock *sk, int level, int optname,
		       char __user *optval, unsigned int optlen,
		       int (*push_pending_frames)(struct sock *));
struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
			     __be32 daddr, __be16 dport, int dif);
struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
			       __be32 daddr, __be16 dport, int dif, int sdif,
			       struct udp_table *tbl, struct sk_buff *skb);
struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb,
				 __be16 sport, __be16 dport);
struct sock *udp6_lib_lookup(struct net *net,
			     const struct in6_addr *saddr, __be16 sport,
			     const struct in6_addr *daddr, __be16 dport,
			     int dif);
struct sock *__udp6_lib_lookup(struct net *net,
			       const struct in6_addr *saddr, __be16 sport,
			       const struct in6_addr *daddr, __be16 dport,
			       int dif, int sdif, struct udp_table *tbl,
			       struct sk_buff *skb);
struct sock *udp6_lib_lookup_skb(const struct sk_buff *skb,
				 __be16 sport, __be16 dport);
int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
		  sk_read_actor_t recv_actor);

/* UDP uses skb->dev_scratch to cache as much information as possible and avoid
 * possibly multiple cache miss on dequeue()
 */
struct udp_dev_scratch {
	/* skb->truesize and the stateless bit are embedded in a single field;
	 * do not use a bitfield since the compiler emits better/smaller code
	 * this way
	 */
	u32 _tsize_state;

#if BITS_PER_LONG == 64
	/* len and the bit needed to compute skb_csum_unnecessary
	 * will be on cold cache lines at recvmsg time.
	 * skb->len can be stored on 16 bits since the udp header has been
	 * already validated and pulled.
	 */
	u16 len;
	bool is_linear;
	bool csum_unnecessary;
#endif
};

static inline struct udp_dev_scratch *udp_skb_scratch(struct sk_buff *skb)
{
	return (struct udp_dev_scratch *)&skb->dev_scratch;
}

#if BITS_PER_LONG == 64
static inline unsigned int udp_skb_len(struct sk_buff *skb)
{
	return udp_skb_scratch(skb)->len;
}

static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
{
	return udp_skb_scratch(skb)->csum_unnecessary;
}

static inline bool udp_skb_is_linear(struct sk_buff *skb)
{
	return udp_skb_scratch(skb)->is_linear;
}

#else
static inline unsigned int udp_skb_len(struct sk_buff *skb)
{
	return skb->len;
}

static inline bool udp_skb_csum_unnecessary(struct sk_buff *skb)
{
	return skb_csum_unnecessary(skb);
}

static inline bool udp_skb_is_linear(struct sk_buff *skb)
{
	return !skb_is_nonlinear(skb);
}
#endif

static inline int copy_linear_skb(struct sk_buff *skb, int len, int off,
				  struct iov_iter *to)
{
	int n;

n = copy_to_iter(skb->data + off, len, to);
	if (n == len)
		return 0;

iov_iter_revert(to, n);
	return -EFAULT;
}

/*
 * 	SNMP statistics for UDP and UDP-Lite
 */
#define UDP_INC_STATS(net, field, is_udplite)		      do { \
	if (is_udplite) SNMP_INC_STATS((net)->mib.udplite_statistics, field);       \
	else		SNMP_INC_STATS((net)->mib.udp_statistics, field);  }  while(0)
#define __UDP_INC_STATS(net, field, is_udplite) 	      do { \
	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_statistics, field);         \
	else		__SNMP_INC_STATS((net)->mib.udp_statistics, field);    }  while(0)

#define __UDP6_INC_STATS(net, field, is_udplite)	    do { \
	if (is_udplite) __SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);\
	else		__SNMP_INC_STATS((net)->mib.udp_stats_in6, field);  \
} while(0)
#define UDP6_INC_STATS(net, field, __lite)		    do { \
	if (__lite) SNMP_INC_STATS((net)->mib.udplite_stats_in6, field);  \
	else	    SNMP_INC_STATS((net)->mib.udp_stats_in6, field);      \
} while(0)

#if IS_ENABLED(CONFIG_IPV6)
#define __UDPX_MIB(sk, ipv4)						\
({									\
	ipv4 ? (IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics :	\
				 sock_net(sk)->mib.udp_statistics) :	\
		(IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_stats_in6 :	\
				 sock_net(sk)->mib.udp_stats_in6);	\
})
#else
#define __UDPX_MIB(sk, ipv4)						\
({									\
	IS_UDPLITE(sk) ? sock_net(sk)->mib.udplite_statistics :		\
			 sock_net(sk)->mib.udp_statistics;		\
})
#endif

#define __UDPX_INC_STATS(sk, field) \
	__SNMP_INC_STATS(__UDPX_MIB(sk, (sk)->sk_family == AF_INET), field)

#ifdef CONFIG_PROC_FS
struct udp_seq_afinfo {
	sa_family_t			family;
	struct udp_table		*udp_table;
};

struct udp_iter_state {
	struct seq_net_private  p;
	int			bucket;
	struct udp_seq_afinfo	*bpf_seq_afinfo;
};

void *udp_seq_start(struct seq_file *seq, loff_t *pos);
void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos);
void udp_seq_stop(struct seq_file *seq, void *v);

extern const struct seq_operations udp_seq_ops;
extern const struct seq_operations udp6_seq_ops;

int udp4_proc_init(void);
void udp4_proc_exit(void);
#endif /* CONFIG_PROC_FS */

int udpv4_offload_init(void);

void udp_init(void);

DECLARE_STATIC_KEY_FALSE(udp_encap_needed_key);
void udp_encap_enable(void);
void udp_encap_disable(void);
#if IS_ENABLED(CONFIG_IPV6)
DECLARE_STATIC_KEY_FALSE(udpv6_encap_needed_key);
void udpv6_encap_enable(void);
#endif

static inline struct sk_buff *udp_rcv_segment(struct sock *sk,
					      struct sk_buff *skb, bool ipv4)
{
	netdev_features_t features = NETIF_F_SG;
	struct sk_buff *segs;

/* Avoid csum recalculation by skb_segment unless userspace explicitly
	 * asks for the final checksum values
	 */
	if (!inet_get_convert_csum(sk))
		features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;

if (skb->pkt_type == PACKET_LOOPBACK)
		skb->ip_summed = CHECKSUM_PARTIAL;

/* the GSO CB lays after the UDP one, no need to save and restore any
	 * CB fragment
	 */
	segs = __skb_gso_segment(skb, features, false);
	if (unlikely(IS_ERR_OR_NULL(segs))) {
		int segs_nr = skb_shinfo(skb)->gso_segs;

atomic_add(segs_nr, &sk->sk_drops);
		SNMP_ADD_STATS(__UDPX_MIB(sk, ipv4), UDP_MIB_INERRORS, segs_nr);
		kfree_skb(skb);
		return NULL;
	}

consume_skb(skb);
	return segs;
}

static inline void udp_post_segment_fix_csum(struct sk_buff *skb)
{
	/* UDP-lite can't land here - no GRO */
	WARN_ON_ONCE(UDP_SKB_CB(skb)->partial_cov);

/* UDP packets generated with UDP_SEGMENT and traversing:
	 *
	 * UDP tunnel(xmit) -> veth (segmentation) -> veth (gro) -> UDP tunnel (rx)
	 *
	 * can reach an UDP socket with CHECKSUM_NONE, because
	 * __iptunnel_pull_header() converts CHECKSUM_PARTIAL into NONE.
	 * SKB_GSO_UDP_L4 or SKB_GSO_FRAGLIST packets with no UDP tunnel will
	 * have a valid checksum, as the GRO engine validates the UDP csum
	 * before the aggregation and nobody strips such info in between.
	 * Instead of adding another check in the tunnel fastpath, we can force
	 * a valid csum after the segmentation.
	 * Additionally fixup the UDP CB.
	 */
	UDP_SKB_CB(skb)->cscov = skb->len;
	if (skb->ip_summed == CHECKSUM_NONE && !skb->csum_valid)
		skb->csum_valid = 1;
}

#ifdef CONFIG_BPF_SYSCALL
struct sk_psock;
struct proto *udp_bpf_get_proto(struct sock *sk, struct sk_psock *psock);
int udp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore);
#endif

#endif	/* _UDP_H */

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