xref: /linux/include/net/inet_sock.h (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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 inet_sock
7  *
8  * Authors:	Many, reorganised here by
9  * 		Arnaldo Carvalho de Melo <acme@mandriva.com>
10  *
11  *		This program is free software; you can redistribute it and/or
12  *		modify it under the terms of the GNU General Public License
13  *		as published by the Free Software Foundation; either version
14  *		2 of the License, or (at your option) any later version.
15  */
16 #ifndef _INET_SOCK_H
17 #define _INET_SOCK_H
18 
19 
20 #include <linux/string.h>
21 #include <linux/types.h>
22 
23 #include <net/flow.h>
24 #include <net/sock.h>
25 #include <net/request_sock.h>
26 
27 /** struct ip_options - IP Options
28  *
29  * @faddr - Saved first hop address
30  * @is_data - Options in __data, rather than skb
31  * @is_strictroute - Strict source route
32  * @srr_is_hit - Packet destination addr was our one
33  * @is_changed - IP checksum more not valid
34  * @rr_needaddr - Need to record addr of outgoing dev
35  * @ts_needtime - Need to record timestamp
36  * @ts_needaddr - Need to record addr of outgoing dev
37  */
38 struct ip_options {
39 	__be32		faddr;
40 	unsigned char	optlen;
41 	unsigned char	srr;
42 	unsigned char	rr;
43 	unsigned char	ts;
44 	unsigned char	is_data:1,
45 			is_strictroute:1,
46 			srr_is_hit:1,
47 			is_changed:1,
48 			rr_needaddr:1,
49 			ts_needtime:1,
50 			ts_needaddr:1;
51 	unsigned char	router_alert;
52 	unsigned char	cipso;
53 	unsigned char	__pad2;
54 	unsigned char	__data[0];
55 };
56 
57 #define optlength(opt) (sizeof(struct ip_options) + opt->optlen)
58 
59 struct inet_request_sock {
60 	struct request_sock	req;
61 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
62 	u16			inet6_rsk_offset;
63 	/* 2 bytes hole, try to pack */
64 #endif
65 	__be32			loc_addr;
66 	__be32			rmt_addr;
67 	__be16			rmt_port;
68 	u16			snd_wscale : 4,
69 				rcv_wscale : 4,
70 				tstamp_ok  : 1,
71 				sack_ok	   : 1,
72 				wscale_ok  : 1,
73 				ecn_ok	   : 1,
74 				acked	   : 1;
75 	struct ip_options	*opt;
76 };
77 
78 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
79 {
80 	return (struct inet_request_sock *)sk;
81 }
82 
83 struct ip_mc_socklist;
84 struct ipv6_pinfo;
85 struct rtable;
86 
87 /** struct inet_sock - representation of INET sockets
88  *
89  * @sk - ancestor class
90  * @pinet6 - pointer to IPv6 control block
91  * @daddr - Foreign IPv4 addr
92  * @rcv_saddr - Bound local IPv4 addr
93  * @dport - Destination port
94  * @num - Local port
95  * @saddr - Sending source
96  * @uc_ttl - Unicast TTL
97  * @sport - Source port
98  * @id - ID counter for DF pkts
99  * @tos - TOS
100  * @mc_ttl - Multicasting TTL
101  * @is_icsk - is this an inet_connection_sock?
102  * @mc_index - Multicast device index
103  * @mc_list - Group array
104  * @cork - info to build ip hdr on each ip frag while socket is corked
105  */
106 struct inet_sock {
107 	/* sk and pinet6 has to be the first two members of inet_sock */
108 	struct sock		sk;
109 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
110 	struct ipv6_pinfo	*pinet6;
111 #endif
112 	/* Socket demultiplex comparisons on incoming packets. */
113 	__be32			daddr;
114 	__be32			rcv_saddr;
115 	__be16			dport;
116 	__u16			num;
117 	__be32			saddr;
118 	__s16			uc_ttl;
119 	__u16			cmsg_flags;
120 	struct ip_options	*opt;
121 	__be16			sport;
122 	__u16			id;
123 	__u8			tos;
124 	__u8			mc_ttl;
125 	__u8			pmtudisc;
126 	__u8			recverr:1,
127 				is_icsk:1,
128 				freebind:1,
129 				hdrincl:1,
130 				mc_loop:1;
131 	int			mc_index;
132 	__be32			mc_addr;
133 	struct ip_mc_socklist	*mc_list;
134 	struct {
135 		unsigned int		flags;
136 		unsigned int		fragsize;
137 		struct ip_options	*opt;
138 		struct rtable		*rt;
139 		int			length; /* Total length of all frames */
140 		__be32			addr;
141 		struct flowi		fl;
142 	} cork;
143 };
144 
145 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
146 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
147 
148 static inline struct inet_sock *inet_sk(const struct sock *sk)
149 {
150 	return (struct inet_sock *)sk;
151 }
152 
153 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
154 					     const struct sock *sk_from,
155 					     const int ancestor_size)
156 {
157 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
158 	       sk_from->sk_prot->obj_size - ancestor_size);
159 }
160 #if !(defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE))
161 static inline void inet_sk_copy_descendant(struct sock *sk_to,
162 					   const struct sock *sk_from)
163 {
164 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
165 }
166 #endif
167 
168 extern int inet_sk_rebuild_header(struct sock *sk);
169 
170 static inline unsigned int inet_ehashfn(const __be32 laddr, const __u16 lport,
171 					const __be32 faddr, const __be16 fport)
172 {
173 	unsigned int h = ((__force __u32)laddr ^ lport) ^ ((__force __u32)faddr ^ (__force __u32)fport);
174 	h ^= h >> 16;
175 	h ^= h >> 8;
176 	return h;
177 }
178 
179 static inline int inet_sk_ehashfn(const struct sock *sk)
180 {
181 	const struct inet_sock *inet = inet_sk(sk);
182 	const __be32 laddr = inet->rcv_saddr;
183 	const __u16 lport = inet->num;
184 	const __be32 faddr = inet->daddr;
185 	const __be16 fport = inet->dport;
186 
187 	return inet_ehashfn(laddr, lport, faddr, fport);
188 }
189 
190 #endif	/* _INET_SOCK_H */
191