1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
3 | * operating system. INET is implemented using the BSD Socket |
4 | * interface as the means of communication with the user level. |
5 | * |
6 | * Definitions for the UDP protocol. |
7 | * |
8 | * Version: @(#)udp.h 1.0.2 04/28/93 |
9 | * |
10 | * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
11 | * |
12 | * This program is free software; you can redistribute it and/or |
13 | * modify it under the terms of the GNU General Public License |
14 | * as published by the Free Software Foundation; either version |
15 | * 2 of the License, or (at your option) any later version. |
16 | */ |
17 | #ifndef _LINUX_UDP_H |
18 | #define _LINUX_UDP_H |
19 | |
20 | #include <net/inet_sock.h> |
21 | #include <linux/skbuff.h> |
22 | #include <net/netns/hash.h> |
23 | #include <uapi/linux/udp.h> |
24 | |
25 | static inline struct udphdr *udp_hdr(const struct sk_buff *skb) |
26 | { |
27 | return (struct udphdr *)skb_transport_header(skb); |
28 | } |
29 | |
30 | static inline struct udphdr *inner_udp_hdr(const struct sk_buff *skb) |
31 | { |
32 | return (struct udphdr *)skb_inner_transport_header(skb); |
33 | } |
34 | |
35 | #define UDP_HTABLE_SIZE_MIN (CONFIG_BASE_SMALL ? 128 : 256) |
36 | |
37 | static inline u32 udp_hashfn(const struct net *net, u32 num, u32 mask) |
38 | { |
39 | return (num + net_hash_mix(net)) & mask; |
40 | } |
41 | |
42 | struct udp_sock { |
43 | /* inet_sock has to be the first member */ |
44 | struct inet_sock inet; |
45 | #define udp_port_hash inet.sk.__sk_common.skc_u16hashes[0] |
46 | #define udp_portaddr_hash inet.sk.__sk_common.skc_u16hashes[1] |
47 | #define udp_portaddr_node inet.sk.__sk_common.skc_portaddr_node |
48 | int pending; /* Any pending frames ? */ |
49 | unsigned int corkflag; /* Cork is required */ |
50 | __u8 encap_type; /* Is this an Encapsulation socket? */ |
51 | unsigned char no_check6_tx:1,/* Send zero UDP6 checksums on TX? */ |
52 | no_check6_rx:1,/* Allow zero UDP6 checksums on RX? */ |
53 | encap_enabled:1, /* This socket enabled encap |
54 | * processing; UDP tunnels and |
55 | * different encapsulation layer set |
56 | * this |
57 | */ |
58 | gro_enabled:1; /* Can accept GRO packets */ |
59 | /* |
60 | * Following member retains the information to create a UDP header |
61 | * when the socket is uncorked. |
62 | */ |
63 | __u16 len; /* total length of pending frames */ |
64 | __u16 gso_size; |
65 | /* |
66 | * Fields specific to UDP-Lite. |
67 | */ |
68 | __u16 pcslen; |
69 | __u16 pcrlen; |
70 | /* indicator bits used by pcflag: */ |
71 | #define UDPLITE_BIT 0x1 /* set by udplite proto init function */ |
72 | #define UDPLITE_SEND_CC 0x2 /* set via udplite setsockopt */ |
73 | #define UDPLITE_RECV_CC 0x4 /* set via udplite setsocktopt */ |
74 | __u8 pcflag; /* marks socket as UDP-Lite if > 0 */ |
75 | __u8 unused[3]; |
76 | /* |
77 | * For encapsulation sockets. |
78 | */ |
79 | int (*encap_rcv)(struct sock *sk, struct sk_buff *skb); |
80 | int (*encap_err_lookup)(struct sock *sk, struct sk_buff *skb); |
81 | void (*encap_destroy)(struct sock *sk); |
82 | |
83 | /* GRO functions for UDP socket */ |
84 | struct sk_buff * (*gro_receive)(struct sock *sk, |
85 | struct list_head *head, |
86 | struct sk_buff *skb); |
87 | int (*gro_complete)(struct sock *sk, |
88 | struct sk_buff *skb, |
89 | int nhoff); |
90 | |
91 | /* udp_recvmsg try to use this before splicing sk_receive_queue */ |
92 | struct sk_buff_head reader_queue ____cacheline_aligned_in_smp; |
93 | |
94 | /* This field is dirtied by udp_recvmsg() */ |
95 | int forward_deficit; |
96 | }; |
97 | |
98 | #define UDP_MAX_SEGMENTS (1 << 6UL) |
99 | |
100 | static inline struct udp_sock *udp_sk(const struct sock *sk) |
101 | { |
102 | return (struct udp_sock *)sk; |
103 | } |
104 | |
105 | static inline void udp_set_no_check6_tx(struct sock *sk, bool val) |
106 | { |
107 | udp_sk(sk)->no_check6_tx = val; |
108 | } |
109 | |
110 | static inline void udp_set_no_check6_rx(struct sock *sk, bool val) |
111 | { |
112 | udp_sk(sk)->no_check6_rx = val; |
113 | } |
114 | |
115 | static inline bool udp_get_no_check6_tx(struct sock *sk) |
116 | { |
117 | return udp_sk(sk)->no_check6_tx; |
118 | } |
119 | |
120 | static inline bool udp_get_no_check6_rx(struct sock *sk) |
121 | { |
122 | return udp_sk(sk)->no_check6_rx; |
123 | } |
124 | |
125 | static inline void udp_cmsg_recv(struct msghdr *msg, struct sock *sk, |
126 | struct sk_buff *skb) |
127 | { |
128 | int gso_size; |
129 | |
130 | if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) { |
131 | gso_size = skb_shinfo(skb)->gso_size; |
132 | put_cmsg(msg, SOL_UDP, UDP_GRO, sizeof(gso_size), &gso_size); |
133 | } |
134 | } |
135 | |
136 | static inline bool udp_unexpected_gso(struct sock *sk, struct sk_buff *skb) |
137 | { |
138 | return !udp_sk(sk)->gro_enabled && skb_is_gso(skb) && |
139 | skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4; |
140 | } |
141 | |
142 | #define udp_portaddr_for_each_entry(__sk, list) \ |
143 | hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node) |
144 | |
145 | #define udp_portaddr_for_each_entry_rcu(__sk, list) \ |
146 | hlist_for_each_entry_rcu(__sk, list, __sk_common.skc_portaddr_node) |
147 | |
148 | #define IS_UDPLITE(__sk) (__sk->sk_protocol == IPPROTO_UDPLITE) |
149 | |
150 | #endif /* _LINUX_UDP_H */ |
151 | |