1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
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.
6 *
7 * Definitions for the UDP protocol.
8 *
9 * Version: @(#)udp.h 1.0.2 04/28/93
10 *
11 * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 */
13 #ifndef _LINUX_UDP_H
14 #define _LINUX_UDP_H
15
16 #include <net/inet_sock.h>
17 #include <linux/skbuff.h>
18 #include <net/netns/hash.h>
19 #include <uapi/linux/udp.h>
20
udp_hdr(const struct sk_buff * skb)21 static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
22 {
23 return (struct udphdr *)skb_transport_header(skb);
24 }
25
inner_udp_hdr(const struct sk_buff * skb)26 static inline struct udphdr *inner_udp_hdr(const struct sk_buff *skb)
27 {
28 return (struct udphdr *)skb_inner_transport_header(skb);
29 }
30
31 #define UDP_HTABLE_SIZE_MIN (CONFIG_BASE_SMALL ? 128 : 256)
32
udp_hashfn(const struct net * net,u32 num,u32 mask)33 static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask)
34 {
35 return (num + net_hash_mix(net)) & mask;
36 }
37
38 struct udp_sock {
39 /* inet_sock has to be the first member */
40 struct inet_sock inet;
41 #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0]
42 #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1]
43 #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node
44 int pending; /* Any pending frames ? */
45 unsigned int corkflag; /* Cork is required */
46 __u8 encap_type; /* Is this an Encapsulation socket? */
47 unsigned char no_check6_tx:1,/* Send zero UDP6 checksums on TX? */
48 no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */
49 encap_enabled:1, /* This socket enabled encap
50 * processing; UDP tunnels and
51 * different encapsulation layer set
52 * this
53 */
54 gro_enabled:1; /* Can accept GRO packets */
55 /*
56 * Following member retains the information to create a UDP header
57 * when the socket is uncorked.
58 */
59 __u16 len; /* total length of pending frames */
60 __u16 gso_size;
61 /*
62 * Fields specific to UDP-Lite.
63 */
64 __u16 pcslen;
65 __u16 pcrlen;
66 /* indicator bits used by pcflag: */
67 #define UDPLITE_BIT 0x1 /* set by udplite proto init function */
68 #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */
69 #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */
70 __u8 pcflag; /* marks socket as UDP-Lite if > 0 */
71 __u8 unused[3];
72 /*
73 * For encapsulation sockets.
74 */
75 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
76 int (*encap_err_lookup)(struct sock *sk, struct sk_buff *skb);
77 void (*encap_destroy)(struct sock *sk);
78
79 /* GRO functions for UDP socket */
80 struct sk_buff * (*gro_receive)(struct sock *sk,
81 struct list_head *head,
82 struct sk_buff *skb);
83 int (*gro_complete)(struct sock *sk,
84 struct sk_buff *skb,
85 int nhoff);
86
87 /* udp_recvmsg try to use this before splicing sk_receive_queue */
88 struct sk_buff_head reader_queue ____cacheline_aligned_in_smp;
89
90 /* This field is dirtied by udp_recvmsg() */
91 int forward_deficit;
92 };
93
94 #define UDP_MAX_SEGMENTS (1 << 6UL)
95
udp_sk(const struct sock * sk)96 static inline struct udp_sock *udp_sk(const struct sock *sk)
97 {
98 return (struct udp_sock *)sk;
99 }
100
udp_set_no_check6_tx(struct sock * sk,bool val)101 static inline void udp_set_no_check6_tx(struct sock *sk, bool val)
102 {
103 udp_sk(sk)->no_check6_tx = val;
104 }
105
udp_set_no_check6_rx(struct sock * sk,bool val)106 static inline void udp_set_no_check6_rx(struct sock *sk, bool val)
107 {
108 udp_sk(sk)->no_check6_rx = val;
109 }
110
udp_get_no_check6_tx(struct sock * sk)111 static inline bool udp_get_no_check6_tx(struct sock *sk)
112 {
113 return udp_sk(sk)->no_check6_tx;
114 }
115
udp_get_no_check6_rx(struct sock * sk)116 static inline bool udp_get_no_check6_rx(struct sock *sk)
117 {
118 return udp_sk(sk)->no_check6_rx;
119 }
120
udp_cmsg_recv(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)121 static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk,
122 struct sk_buff *skb)
123 {
124 int gso_size;
125
126 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
127 gso_size = skb_shinfo(skb)->gso_size;
128 put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size);
129 }
130 }
131
udp_unexpected_gso(struct sock * sk,struct sk_buff * skb)132 static inline bool udp_unexpected_gso(struct sock *sk, struct sk_buff *skb)
133 {
134 return !udp_sk(sk)->gro_enabled && skb_is_gso(skb) &&
135 skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4;
136 }
137
138 #define udp_portaddr_for_each_entry(__sk, list) \
139 hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
140
141 #define udp_portaddr_for_each_entry_rcu(__sk, list) \
142 hlist_for_each_entry_rcu(__sk, list, __sk_common.skc_portaddr_node)
143
144 #define IS_UDPLITE(__sk) (__sk->sk_protocol == IPPROTO_UDPLITE)
145
146 #endif /* _LINUX_UDP_H */
147
