xref: /linux/include/net/inet_sock.h (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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/kmemcheck.h>
21 #include <linux/string.h>
22 #include <linux/types.h>
23 #include <linux/jhash.h>
24 #include <linux/netdevice.h>
25 
26 #include <net/flow.h>
27 #include <net/sock.h>
28 #include <net/request_sock.h>
29 #include <net/netns/hash.h>
30 
31 /** struct ip_options - IP Options
32  *
33  * @faddr - Saved first hop address
34  * @is_data - Options in __data, rather than skb
35  * @is_strictroute - Strict source route
36  * @srr_is_hit - Packet destination addr was our one
37  * @is_changed - IP checksum more not valid
38  * @rr_needaddr - Need to record addr of outgoing dev
39  * @ts_needtime - Need to record timestamp
40  * @ts_needaddr - Need to record addr of outgoing dev
41  */
42 struct ip_options {
43 	__be32		faddr;
44 	unsigned char	optlen;
45 	unsigned char	srr;
46 	unsigned char	rr;
47 	unsigned char	ts;
48 	unsigned char	is_strictroute:1,
49 			srr_is_hit:1,
50 			is_changed:1,
51 			rr_needaddr:1,
52 			ts_needtime:1,
53 			ts_needaddr:1;
54 	unsigned char	router_alert;
55 	unsigned char	cipso;
56 	unsigned char	__pad2;
57 	unsigned char	__data[0];
58 };
59 
60 struct ip_options_rcu {
61 	struct rcu_head rcu;
62 	struct ip_options opt;
63 };
64 
65 struct ip_options_data {
66 	struct ip_options_rcu	opt;
67 	char			data[40];
68 };
69 
70 struct inet_request_sock {
71 	struct request_sock	req;
72 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
73 	u16			inet6_rsk_offset;
74 #endif
75 	__be16			loc_port;
76 	__be32			loc_addr;
77 	__be32			rmt_addr;
78 	__be16			rmt_port;
79 	kmemcheck_bitfield_begin(flags);
80 	u16			snd_wscale : 4,
81 				rcv_wscale : 4,
82 				tstamp_ok  : 1,
83 				sack_ok	   : 1,
84 				wscale_ok  : 1,
85 				ecn_ok	   : 1,
86 				acked	   : 1,
87 				no_srccheck: 1;
88 	kmemcheck_bitfield_end(flags);
89 	struct ip_options_rcu	*opt;
90 };
91 
92 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
93 {
94 	return (struct inet_request_sock *)sk;
95 }
96 
97 struct inet_cork {
98 	unsigned int		flags;
99 	__be32			addr;
100 	struct ip_options	*opt;
101 	unsigned int		fragsize;
102 	struct dst_entry	*dst;
103 	int			length; /* Total length of all frames */
104 	struct page		*page;
105 	u32			off;
106 	u8			tx_flags;
107 };
108 
109 struct inet_cork_full {
110 	struct inet_cork	base;
111 	struct flowi		fl;
112 };
113 
114 struct ip_mc_socklist;
115 struct ipv6_pinfo;
116 struct rtable;
117 
118 /** struct inet_sock - representation of INET sockets
119  *
120  * @sk - ancestor class
121  * @pinet6 - pointer to IPv6 control block
122  * @inet_daddr - Foreign IPv4 addr
123  * @inet_rcv_saddr - Bound local IPv4 addr
124  * @inet_dport - Destination port
125  * @inet_num - Local port
126  * @inet_saddr - Sending source
127  * @uc_ttl - Unicast TTL
128  * @inet_sport - Source port
129  * @inet_id - ID counter for DF pkts
130  * @tos - TOS
131  * @mc_ttl - Multicasting TTL
132  * @is_icsk - is this an inet_connection_sock?
133  * @mc_index - Multicast device index
134  * @mc_list - Group array
135  * @cork - info to build ip hdr on each ip frag while socket is corked
136  */
137 struct inet_sock {
138 	/* sk and pinet6 has to be the first two members of inet_sock */
139 	struct sock		sk;
140 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
141 	struct ipv6_pinfo	*pinet6;
142 #endif
143 	/* Socket demultiplex comparisons on incoming packets. */
144 #define inet_daddr		sk.__sk_common.skc_daddr
145 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
146 
147 	__be16			inet_dport;
148 	__u16			inet_num;
149 	__be32			inet_saddr;
150 	__s16			uc_ttl;
151 	__u16			cmsg_flags;
152 	__be16			inet_sport;
153 	__u16			inet_id;
154 
155 	struct ip_options_rcu __rcu	*inet_opt;
156 	__u8			tos;
157 	__u8			min_ttl;
158 	__u8			mc_ttl;
159 	__u8			pmtudisc;
160 	__u8			recverr:1,
161 				is_icsk:1,
162 				freebind:1,
163 				hdrincl:1,
164 				mc_loop:1,
165 				transparent:1,
166 				mc_all:1,
167 				nodefrag:1;
168 	int			mc_index;
169 	__be32			mc_addr;
170 	struct ip_mc_socklist __rcu	*mc_list;
171 	struct inet_cork_full	cork;
172 };
173 
174 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
175 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
176 
177 static inline struct inet_sock *inet_sk(const struct sock *sk)
178 {
179 	return (struct inet_sock *)sk;
180 }
181 
182 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
183 					     const struct sock *sk_from,
184 					     const int ancestor_size)
185 {
186 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
187 	       sk_from->sk_prot->obj_size - ancestor_size);
188 }
189 #if !(defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE))
190 static inline void inet_sk_copy_descendant(struct sock *sk_to,
191 					   const struct sock *sk_from)
192 {
193 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
194 }
195 #endif
196 
197 extern int inet_sk_rebuild_header(struct sock *sk);
198 
199 extern u32 inet_ehash_secret;
200 extern void build_ehash_secret(void);
201 
202 static inline unsigned int inet_ehashfn(struct net *net,
203 					const __be32 laddr, const __u16 lport,
204 					const __be32 faddr, const __be16 fport)
205 {
206 	return jhash_3words((__force __u32) laddr,
207 			    (__force __u32) faddr,
208 			    ((__u32) lport) << 16 | (__force __u32)fport,
209 			    inet_ehash_secret + net_hash_mix(net));
210 }
211 
212 static inline int inet_sk_ehashfn(const struct sock *sk)
213 {
214 	const struct inet_sock *inet = inet_sk(sk);
215 	const __be32 laddr = inet->inet_rcv_saddr;
216 	const __u16 lport = inet->inet_num;
217 	const __be32 faddr = inet->inet_daddr;
218 	const __be16 fport = inet->inet_dport;
219 	struct net *net = sock_net(sk);
220 
221 	return inet_ehashfn(net, laddr, lport, faddr, fport);
222 }
223 
224 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
225 {
226 	struct request_sock *req = reqsk_alloc(ops);
227 	struct inet_request_sock *ireq = inet_rsk(req);
228 
229 	if (req != NULL) {
230 		kmemcheck_annotate_bitfield(ireq, flags);
231 		ireq->opt = NULL;
232 	}
233 
234 	return req;
235 }
236 
237 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
238 {
239 	__u8 flags = 0;
240 
241 	if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
242 		flags |= FLOWI_FLAG_ANYSRC;
243 	if (sk->sk_protocol == IPPROTO_TCP)
244 		flags |= FLOWI_FLAG_PRECOW_METRICS;
245 	return flags;
246 }
247 
248 #endif	/* _INET_SOCK_H */
249