xref: /linux/include/net/inet_sock.h (revision 33619f0d3ff715a2a5499520967d526ad931d70d)
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 #define optlength(opt) (sizeof(struct ip_options) + opt->optlen)
61 
62 struct inet_request_sock {
63 	struct request_sock	req;
64 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
65 	u16			inet6_rsk_offset;
66 #endif
67 	__be16			loc_port;
68 	__be32			loc_addr;
69 	__be32			rmt_addr;
70 	__be16			rmt_port;
71 	kmemcheck_bitfield_begin(flags);
72 	u16			snd_wscale : 4,
73 				rcv_wscale : 4,
74 				tstamp_ok  : 1,
75 				sack_ok	   : 1,
76 				wscale_ok  : 1,
77 				ecn_ok	   : 1,
78 				acked	   : 1,
79 				no_srccheck: 1;
80 	kmemcheck_bitfield_end(flags);
81 	struct ip_options	*opt;
82 };
83 
84 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
85 {
86 	return (struct inet_request_sock *)sk;
87 }
88 
89 struct ip_mc_socklist;
90 struct ipv6_pinfo;
91 struct rtable;
92 
93 /** struct inet_sock - representation of INET sockets
94  *
95  * @sk - ancestor class
96  * @pinet6 - pointer to IPv6 control block
97  * @inet_daddr - Foreign IPv4 addr
98  * @inet_rcv_saddr - Bound local IPv4 addr
99  * @inet_dport - Destination port
100  * @inet_num - Local port
101  * @inet_saddr - Sending source
102  * @uc_ttl - Unicast TTL
103  * @inet_sport - Source port
104  * @inet_id - ID counter for DF pkts
105  * @tos - TOS
106  * @mc_ttl - Multicasting TTL
107  * @is_icsk - is this an inet_connection_sock?
108  * @mc_index - Multicast device index
109  * @mc_list - Group array
110  * @cork - info to build ip hdr on each ip frag while socket is corked
111  */
112 struct inet_sock {
113 	/* sk and pinet6 has to be the first two members of inet_sock */
114 	struct sock		sk;
115 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
116 	struct ipv6_pinfo	*pinet6;
117 #endif
118 	/* Socket demultiplex comparisons on incoming packets. */
119 #define inet_daddr		sk.__sk_common.skc_daddr
120 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
121 
122 	__be16			inet_dport;
123 	__u16			inet_num;
124 	__be32			inet_saddr;
125 	__s16			uc_ttl;
126 	__u16			cmsg_flags;
127 	__be16			inet_sport;
128 	__u16			inet_id;
129 
130 	struct ip_options	*opt;
131 	__u8			tos;
132 	__u8			min_ttl;
133 	__u8			mc_ttl;
134 	__u8			pmtudisc;
135 	__u8			recverr:1,
136 				is_icsk:1,
137 				freebind:1,
138 				hdrincl:1,
139 				mc_loop:1,
140 				transparent:1,
141 				mc_all:1,
142 				nodefrag:1;
143 	int			mc_index;
144 	__be32			mc_addr;
145 	struct ip_mc_socklist __rcu	*mc_list;
146 	struct {
147 		unsigned int		flags;
148 		unsigned int		fragsize;
149 		struct ip_options	*opt;
150 		struct dst_entry	*dst;
151 		int			length; /* Total length of all frames */
152 		__be32			addr;
153 		struct flowi		fl;
154 	} cork;
155 };
156 
157 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
158 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
159 
160 static inline struct inet_sock *inet_sk(const struct sock *sk)
161 {
162 	return (struct inet_sock *)sk;
163 }
164 
165 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
166 					     const struct sock *sk_from,
167 					     const int ancestor_size)
168 {
169 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
170 	       sk_from->sk_prot->obj_size - ancestor_size);
171 }
172 #if !(defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE))
173 static inline void inet_sk_copy_descendant(struct sock *sk_to,
174 					   const struct sock *sk_from)
175 {
176 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
177 }
178 #endif
179 
180 extern int inet_sk_rebuild_header(struct sock *sk);
181 
182 extern u32 inet_ehash_secret;
183 extern void build_ehash_secret(void);
184 
185 static inline unsigned int inet_ehashfn(struct net *net,
186 					const __be32 laddr, const __u16 lport,
187 					const __be32 faddr, const __be16 fport)
188 {
189 	return jhash_3words((__force __u32) laddr,
190 			    (__force __u32) faddr,
191 			    ((__u32) lport) << 16 | (__force __u32)fport,
192 			    inet_ehash_secret + net_hash_mix(net));
193 }
194 
195 static inline int inet_sk_ehashfn(const struct sock *sk)
196 {
197 	const struct inet_sock *inet = inet_sk(sk);
198 	const __be32 laddr = inet->inet_rcv_saddr;
199 	const __u16 lport = inet->inet_num;
200 	const __be32 faddr = inet->inet_daddr;
201 	const __be16 fport = inet->inet_dport;
202 	struct net *net = sock_net(sk);
203 
204 	return inet_ehashfn(net, laddr, lport, faddr, fport);
205 }
206 
207 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
208 {
209 	struct request_sock *req = reqsk_alloc(ops);
210 	struct inet_request_sock *ireq = inet_rsk(req);
211 
212 	if (req != NULL) {
213 		kmemcheck_annotate_bitfield(ireq, flags);
214 		ireq->opt = NULL;
215 	}
216 
217 	return req;
218 }
219 
220 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
221 {
222 	return inet_sk(sk)->transparent ? FLOWI_FLAG_ANYSRC : 0;
223 }
224 
225 #endif	/* _INET_SOCK_H */
226