xref: /linux/include/net/inet_sock.h (revision d458cdf712e0c671e8e819abb16ecd6e44f9daec)
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  * @nexthop - Saved nexthop address in LSRR and SSRR
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 	__be32		nexthop;
45 	unsigned char	optlen;
46 	unsigned char	srr;
47 	unsigned char	rr;
48 	unsigned char	ts;
49 	unsigned char	is_strictroute:1,
50 			srr_is_hit:1,
51 			is_changed:1,
52 			rr_needaddr:1,
53 			ts_needtime:1,
54 			ts_needaddr:1;
55 	unsigned char	router_alert;
56 	unsigned char	cipso;
57 	unsigned char	__pad2;
58 	unsigned char	__data[0];
59 };
60 
61 struct ip_options_rcu {
62 	struct rcu_head rcu;
63 	struct ip_options opt;
64 };
65 
66 struct ip_options_data {
67 	struct ip_options_rcu	opt;
68 	char			data[40];
69 };
70 
71 struct inet_request_sock {
72 	struct request_sock	req;
73 #if IS_ENABLED(CONFIG_IPV6)
74 	u16			inet6_rsk_offset;
75 #endif
76 	__be16			loc_port;
77 	__be32			loc_addr;
78 	__be32			rmt_addr;
79 	__be16			rmt_port;
80 	kmemcheck_bitfield_begin(flags);
81 	u16			snd_wscale : 4,
82 				rcv_wscale : 4,
83 				tstamp_ok  : 1,
84 				sack_ok	   : 1,
85 				wscale_ok  : 1,
86 				ecn_ok	   : 1,
87 				acked	   : 1,
88 				no_srccheck: 1;
89 	kmemcheck_bitfield_end(flags);
90 	struct ip_options_rcu	*opt;
91 };
92 
93 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
94 {
95 	return (struct inet_request_sock *)sk;
96 }
97 
98 struct inet_cork {
99 	unsigned int		flags;
100 	__be32			addr;
101 	struct ip_options	*opt;
102 	unsigned int		fragsize;
103 	int			length; /* Total length of all frames */
104 	struct dst_entry	*dst;
105 	u8			tx_flags;
106 	__u8			ttl;
107 	__s16			tos;
108 	char			priority;
109 };
110 
111 struct inet_cork_full {
112 	struct inet_cork	base;
113 	struct flowi		fl;
114 };
115 
116 struct ip_mc_socklist;
117 struct ipv6_pinfo;
118 struct rtable;
119 
120 /** struct inet_sock - representation of INET sockets
121  *
122  * @sk - ancestor class
123  * @pinet6 - pointer to IPv6 control block
124  * @inet_daddr - Foreign IPv4 addr
125  * @inet_rcv_saddr - Bound local IPv4 addr
126  * @inet_dport - Destination port
127  * @inet_num - Local port
128  * @inet_saddr - Sending source
129  * @uc_ttl - Unicast TTL
130  * @inet_sport - Source port
131  * @inet_id - ID counter for DF pkts
132  * @tos - TOS
133  * @mc_ttl - Multicasting TTL
134  * @is_icsk - is this an inet_connection_sock?
135  * @uc_index - Unicast outgoing device index
136  * @mc_index - Multicast device index
137  * @mc_list - Group array
138  * @cork - info to build ip hdr on each ip frag while socket is corked
139  */
140 struct inet_sock {
141 	/* sk and pinet6 has to be the first two members of inet_sock */
142 	struct sock		sk;
143 #if IS_ENABLED(CONFIG_IPV6)
144 	struct ipv6_pinfo	*pinet6;
145 #endif
146 	/* Socket demultiplex comparisons on incoming packets. */
147 #define inet_daddr		sk.__sk_common.skc_daddr
148 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
149 #define inet_addrpair		sk.__sk_common.skc_addrpair
150 #define inet_dport		sk.__sk_common.skc_dport
151 #define inet_num		sk.__sk_common.skc_num
152 #define inet_portpair		sk.__sk_common.skc_portpair
153 
154 	__be32			inet_saddr;
155 	__s16			uc_ttl;
156 	__u16			cmsg_flags;
157 	__be16			inet_sport;
158 	__u16			inet_id;
159 
160 	struct ip_options_rcu __rcu	*inet_opt;
161 	int			rx_dst_ifindex;
162 	__u8			tos;
163 	__u8			min_ttl;
164 	__u8			mc_ttl;
165 	__u8			pmtudisc;
166 	__u8			recverr:1,
167 				is_icsk:1,
168 				freebind:1,
169 				hdrincl:1,
170 				mc_loop:1,
171 				transparent:1,
172 				mc_all:1,
173 				nodefrag:1;
174 	__u8			rcv_tos;
175 	int			uc_index;
176 	int			mc_index;
177 	__be32			mc_addr;
178 	struct ip_mc_socklist __rcu	*mc_list;
179 	struct inet_cork_full	cork;
180 };
181 
182 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
183 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
184 
185 static inline struct inet_sock *inet_sk(const struct sock *sk)
186 {
187 	return (struct inet_sock *)sk;
188 }
189 
190 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
191 					     const struct sock *sk_from,
192 					     const int ancestor_size)
193 {
194 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
195 	       sk_from->sk_prot->obj_size - ancestor_size);
196 }
197 #if !(IS_ENABLED(CONFIG_IPV6))
198 static inline void inet_sk_copy_descendant(struct sock *sk_to,
199 					   const struct sock *sk_from)
200 {
201 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
202 }
203 #endif
204 
205 int inet_sk_rebuild_header(struct sock *sk);
206 
207 extern u32 inet_ehash_secret;
208 extern u32 ipv6_hash_secret;
209 void build_ehash_secret(void);
210 
211 static inline unsigned int inet_ehashfn(struct net *net,
212 					const __be32 laddr, const __u16 lport,
213 					const __be32 faddr, const __be16 fport)
214 {
215 	return jhash_3words((__force __u32) laddr,
216 			    (__force __u32) faddr,
217 			    ((__u32) lport) << 16 | (__force __u32)fport,
218 			    inet_ehash_secret + net_hash_mix(net));
219 }
220 
221 static inline int inet_sk_ehashfn(const struct sock *sk)
222 {
223 	const struct inet_sock *inet = inet_sk(sk);
224 	const __be32 laddr = inet->inet_rcv_saddr;
225 	const __u16 lport = inet->inet_num;
226 	const __be32 faddr = inet->inet_daddr;
227 	const __be16 fport = inet->inet_dport;
228 	struct net *net = sock_net(sk);
229 
230 	return inet_ehashfn(net, laddr, lport, faddr, fport);
231 }
232 
233 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
234 {
235 	struct request_sock *req = reqsk_alloc(ops);
236 	struct inet_request_sock *ireq = inet_rsk(req);
237 
238 	if (req != NULL) {
239 		kmemcheck_annotate_bitfield(ireq, flags);
240 		ireq->opt = NULL;
241 	}
242 
243 	return req;
244 }
245 
246 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
247 {
248 	__u8 flags = 0;
249 
250 	if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
251 		flags |= FLOWI_FLAG_ANYSRC;
252 	return flags;
253 }
254 
255 #endif	/* _INET_SOCK_H */
256