1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * Definitions for the UDP protocol.
9 * Version: @(#)udp.h 1.0.2 04/28/93
11 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
16 #include <net/inet_sock.h>
17 #include <linux/skbuff.h>
18 #include <net/netns/hash.h>
19 #include <uapi/linux/udp.h>
21 static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
23 return (struct udphdr *)skb_transport_header(skb);
26 #define UDP_HTABLE_SIZE_MIN_PERNET 128
27 #define UDP_HTABLE_SIZE_MIN (CONFIG_BASE_SMALL ? 128 : 256)
28 #define UDP_HTABLE_SIZE_MAX 65536
30 static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask)
32 return (num + net_hash_mix(net)) & mask;
36 UDP_FLAGS_CORK, /* Cork is required */
37 UDP_FLAGS_NO_CHECK6_TX, /* Send zero UDP6 checksums on TX? */
38 UDP_FLAGS_NO_CHECK6_RX, /* Allow zero UDP6 checksums on RX? */
39 UDP_FLAGS_GRO_ENABLED, /* Request GRO aggregation */
40 UDP_FLAGS_ACCEPT_FRAGLIST,
42 UDP_FLAGS_ENCAP_ENABLED, /* This socket enabled encap */
46 /* inet_sock has to be the first member */
47 struct inet_sock inet;
48 #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0]
49 #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1]
50 #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node
52 unsigned long udp_flags;
54 int pending; /* Any pending frames ? */
55 __u8 encap_type; /* Is this an Encapsulation socket? */
57 /* indicator bits used by pcflag: */
58 #define UDPLITE_BIT 0x1 /* set by udplite proto init function */
59 #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */
60 #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */
61 __u8 pcflag; /* marks socket as UDP-Lite if > 0 */
63 * Following member retains the information to create a UDP header
64 * when the socket is uncorked.
66 __u16 len; /* total length of pending frames */
69 * Fields specific to UDP-Lite.
74 * For encapsulation sockets.
76 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
77 void (*encap_err_rcv)(struct sock *sk, struct sk_buff *skb, int err,
78 __be16 port, u32 info, u8 *payload);
79 int (*encap_err_lookup)(struct sock *sk, struct sk_buff *skb);
80 void (*encap_destroy)(struct sock *sk);
82 /* GRO functions for UDP socket */
83 struct sk_buff * (*gro_receive)(struct sock *sk,
84 struct list_head *head,
86 int (*gro_complete)(struct sock *sk,
90 /* udp_recvmsg try to use this before splicing sk_receive_queue */
91 struct sk_buff_head reader_queue ____cacheline_aligned_in_smp;
93 /* This field is dirtied by udp_recvmsg() */
96 /* This fields follows rcvbuf value, and is touched by udp_recvmsg */
97 int forward_threshold;
100 #define udp_test_bit(nr, sk) \
101 test_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
102 #define udp_set_bit(nr, sk) \
103 set_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
104 #define udp_test_and_set_bit(nr, sk) \
105 test_and_set_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
106 #define udp_clear_bit(nr, sk) \
107 clear_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags)
108 #define udp_assign_bit(nr, sk, val) \
109 assign_bit(UDP_FLAGS_##nr, &udp_sk(sk)->udp_flags, val)
111 #define UDP_MAX_SEGMENTS (1 << 6UL)
113 #define udp_sk(ptr) container_of_const(ptr, struct udp_sock, inet.sk)
115 static inline void udp_set_no_check6_tx(struct sock *sk, bool val)
117 udp_assign_bit(NO_CHECK6_TX, sk, val);
120 static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
122 udp_assign_bit(NO_CHECK6_RX, sk, val);
125 static inline bool udp_get_no_check6_tx(const struct sock *sk)
127 return udp_test_bit(NO_CHECK6_TX, sk);
130 static inline bool udp_get_no_check6_rx(const struct sock *sk)
132 return udp_test_bit(NO_CHECK6_RX, sk);
135 static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk,
140 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
141 gso_size = skb_shinfo(skb)->gso_size;
142 put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size);
146 static inline bool udp_unexpected_gso(struct sock *sk, struct sk_buff *skb)
148 if (!skb_is_gso(skb))
151 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4 &&
152 !udp_test_bit(ACCEPT_L4, sk))
155 if (skb_shinfo(skb)->gso_type & SKB_GSO_FRAGLIST &&
156 !udp_test_bit(ACCEPT_FRAGLIST, sk))
162 static inline void udp_allow_gso(struct sock *sk)
164 udp_set_bit(ACCEPT_L4, sk);
165 udp_set_bit(ACCEPT_FRAGLIST, sk);
168 #define udp_portaddr_for_each_entry(__sk, list) \
169 hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
171 #define udp_portaddr_for_each_entry_rcu(__sk, list) \
172 hlist_for_each_entry_rcu(__sk, list, __sk_common.skc_portaddr_node)
174 #define IS_UDPLITE(__sk) (__sk->sk_protocol == IPPROTO_UDPLITE)
176 #endif /* _LINUX_UDP_H */