xref: /linux/include/net/inet_sock.h (revision 1e1159bb97cf4191849b4b03f77ab32977c2ece6)
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 };
107 
108 struct inet_cork_full {
109 	struct inet_cork	base;
110 	struct flowi		fl;
111 };
112 
113 struct ip_mc_socklist;
114 struct ipv6_pinfo;
115 struct rtable;
116 
117 /** struct inet_sock - representation of INET sockets
118  *
119  * @sk - ancestor class
120  * @pinet6 - pointer to IPv6 control block
121  * @inet_daddr - Foreign IPv4 addr
122  * @inet_rcv_saddr - Bound local IPv4 addr
123  * @inet_dport - Destination port
124  * @inet_num - Local port
125  * @inet_saddr - Sending source
126  * @uc_ttl - Unicast TTL
127  * @inet_sport - Source port
128  * @inet_id - ID counter for DF pkts
129  * @tos - TOS
130  * @mc_ttl - Multicasting TTL
131  * @is_icsk - is this an inet_connection_sock?
132  * @uc_index - Unicast outgoing device index
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 IS_ENABLED(CONFIG_IPV6)
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 #define inet_addrpair		sk.__sk_common.skc_addrpair
147 #define inet_dport		sk.__sk_common.skc_dport
148 #define inet_num		sk.__sk_common.skc_num
149 #define inet_portpair		sk.__sk_common.skc_portpair
150 
151 	__be32			inet_saddr;
152 	__s16			uc_ttl;
153 	__u16			cmsg_flags;
154 	__be16			inet_sport;
155 	__u16			inet_id;
156 
157 	struct ip_options_rcu __rcu	*inet_opt;
158 	int			rx_dst_ifindex;
159 	__u8			tos;
160 	__u8			min_ttl;
161 	__u8			mc_ttl;
162 	__u8			pmtudisc;
163 	__u8			recverr:1,
164 				is_icsk:1,
165 				freebind:1,
166 				hdrincl:1,
167 				mc_loop:1,
168 				transparent:1,
169 				mc_all:1,
170 				nodefrag:1;
171 	__u8			rcv_tos;
172 	int			uc_index;
173 	int			mc_index;
174 	__be32			mc_addr;
175 	struct ip_mc_socklist __rcu	*mc_list;
176 	struct inet_cork_full	cork;
177 };
178 
179 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
180 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
181 
182 static inline struct inet_sock *inet_sk(const struct sock *sk)
183 {
184 	return (struct inet_sock *)sk;
185 }
186 
187 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
188 					     const struct sock *sk_from,
189 					     const int ancestor_size)
190 {
191 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
192 	       sk_from->sk_prot->obj_size - ancestor_size);
193 }
194 #if !(IS_ENABLED(CONFIG_IPV6))
195 static inline void inet_sk_copy_descendant(struct sock *sk_to,
196 					   const struct sock *sk_from)
197 {
198 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
199 }
200 #endif
201 
202 extern int inet_sk_rebuild_header(struct sock *sk);
203 
204 extern u32 inet_ehash_secret;
205 extern u32 ipv6_hash_secret;
206 extern void build_ehash_secret(void);
207 
208 static inline unsigned int inet_ehashfn(struct net *net,
209 					const __be32 laddr, const __u16 lport,
210 					const __be32 faddr, const __be16 fport)
211 {
212 	return jhash_3words((__force __u32) laddr,
213 			    (__force __u32) faddr,
214 			    ((__u32) lport) << 16 | (__force __u32)fport,
215 			    inet_ehash_secret + net_hash_mix(net));
216 }
217 
218 static inline int inet_sk_ehashfn(const struct sock *sk)
219 {
220 	const struct inet_sock *inet = inet_sk(sk);
221 	const __be32 laddr = inet->inet_rcv_saddr;
222 	const __u16 lport = inet->inet_num;
223 	const __be32 faddr = inet->inet_daddr;
224 	const __be16 fport = inet->inet_dport;
225 	struct net *net = sock_net(sk);
226 
227 	return inet_ehashfn(net, laddr, lport, faddr, fport);
228 }
229 
230 static inline struct request_sock *inet_reqsk_alloc(struct request_sock_ops *ops)
231 {
232 	struct request_sock *req = reqsk_alloc(ops);
233 	struct inet_request_sock *ireq = inet_rsk(req);
234 
235 	if (req != NULL) {
236 		kmemcheck_annotate_bitfield(ireq, flags);
237 		ireq->opt = NULL;
238 	}
239 
240 	return req;
241 }
242 
243 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
244 {
245 	__u8 flags = 0;
246 
247 	if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
248 		flags |= FLOWI_FLAG_ANYSRC;
249 	return flags;
250 }
251 
252 #endif	/* _INET_SOCK_H */
253