xref: /linux/include/net/inet_sock.h (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
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 #include <linux/bitops.h>
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 #include <net/tcp_states.h>
31 
32 /** struct ip_options - IP Options
33  *
34  * @faddr - Saved first hop address
35  * @nexthop - Saved nexthop address in LSRR and SSRR
36  * @is_strictroute - Strict source route
37  * @srr_is_hit - Packet destination addr was our one
38  * @is_changed - IP checksum more not valid
39  * @rr_needaddr - Need to record addr of outgoing dev
40  * @ts_needtime - Need to record timestamp
41  * @ts_needaddr - Need to record addr of outgoing dev
42  */
43 struct ip_options {
44 	__be32		faddr;
45 	__be32		nexthop;
46 	unsigned char	optlen;
47 	unsigned char	srr;
48 	unsigned char	rr;
49 	unsigned char	ts;
50 	unsigned char	is_strictroute:1,
51 			srr_is_hit:1,
52 			is_changed:1,
53 			rr_needaddr:1,
54 			ts_needtime:1,
55 			ts_needaddr:1;
56 	unsigned char	router_alert;
57 	unsigned char	cipso;
58 	unsigned char	__pad2;
59 	unsigned char	__data[0];
60 };
61 
62 struct ip_options_rcu {
63 	struct rcu_head rcu;
64 	struct ip_options opt;
65 };
66 
67 struct ip_options_data {
68 	struct ip_options_rcu	opt;
69 	char			data[40];
70 };
71 
72 struct inet_request_sock {
73 	struct request_sock	req;
74 #define ir_loc_addr		req.__req_common.skc_rcv_saddr
75 #define ir_rmt_addr		req.__req_common.skc_daddr
76 #define ir_num			req.__req_common.skc_num
77 #define ir_rmt_port		req.__req_common.skc_dport
78 #define ir_v6_rmt_addr		req.__req_common.skc_v6_daddr
79 #define ir_v6_loc_addr		req.__req_common.skc_v6_rcv_saddr
80 #define ir_iif			req.__req_common.skc_bound_dev_if
81 #define ir_cookie		req.__req_common.skc_cookie
82 #define ireq_net		req.__req_common.skc_net
83 #define ireq_state		req.__req_common.skc_state
84 #define ireq_family		req.__req_common.skc_family
85 
86 	kmemcheck_bitfield_begin(flags);
87 	u16			snd_wscale : 4,
88 				rcv_wscale : 4,
89 				tstamp_ok  : 1,
90 				sack_ok	   : 1,
91 				wscale_ok  : 1,
92 				ecn_ok	   : 1,
93 				acked	   : 1,
94 				no_srccheck: 1;
95 	kmemcheck_bitfield_end(flags);
96 	u32                     ir_mark;
97 	union {
98 		struct ip_options_rcu	*opt;
99 		struct sk_buff		*pktopts;
100 	};
101 };
102 
103 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
104 {
105 	return (struct inet_request_sock *)sk;
106 }
107 
108 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
109 {
110 	if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
111 		return skb->mark;
112 
113 	return sk->sk_mark;
114 }
115 
116 struct inet_cork {
117 	unsigned int		flags;
118 	__be32			addr;
119 	struct ip_options	*opt;
120 	unsigned int		fragsize;
121 	int			length; /* Total length of all frames */
122 	struct dst_entry	*dst;
123 	u8			tx_flags;
124 	__u8			ttl;
125 	__s16			tos;
126 	char			priority;
127 };
128 
129 struct inet_cork_full {
130 	struct inet_cork	base;
131 	struct flowi		fl;
132 };
133 
134 struct ip_mc_socklist;
135 struct ipv6_pinfo;
136 struct rtable;
137 
138 /** struct inet_sock - representation of INET sockets
139  *
140  * @sk - ancestor class
141  * @pinet6 - pointer to IPv6 control block
142  * @inet_daddr - Foreign IPv4 addr
143  * @inet_rcv_saddr - Bound local IPv4 addr
144  * @inet_dport - Destination port
145  * @inet_num - Local port
146  * @inet_saddr - Sending source
147  * @uc_ttl - Unicast TTL
148  * @inet_sport - Source port
149  * @inet_id - ID counter for DF pkts
150  * @tos - TOS
151  * @mc_ttl - Multicasting TTL
152  * @is_icsk - is this an inet_connection_sock?
153  * @uc_index - Unicast outgoing device index
154  * @mc_index - Multicast device index
155  * @mc_list - Group array
156  * @cork - info to build ip hdr on each ip frag while socket is corked
157  */
158 struct inet_sock {
159 	/* sk and pinet6 has to be the first two members of inet_sock */
160 	struct sock		sk;
161 #if IS_ENABLED(CONFIG_IPV6)
162 	struct ipv6_pinfo	*pinet6;
163 #endif
164 	/* Socket demultiplex comparisons on incoming packets. */
165 #define inet_daddr		sk.__sk_common.skc_daddr
166 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
167 #define inet_dport		sk.__sk_common.skc_dport
168 #define inet_num		sk.__sk_common.skc_num
169 
170 	__be32			inet_saddr;
171 	__s16			uc_ttl;
172 	__u16			cmsg_flags;
173 	__be16			inet_sport;
174 	__u16			inet_id;
175 
176 	struct ip_options_rcu __rcu	*inet_opt;
177 	int			rx_dst_ifindex;
178 	__u8			tos;
179 	__u8			min_ttl;
180 	__u8			mc_ttl;
181 	__u8			pmtudisc;
182 	__u8			recverr:1,
183 				is_icsk:1,
184 				freebind:1,
185 				hdrincl:1,
186 				mc_loop:1,
187 				transparent:1,
188 				mc_all:1,
189 				nodefrag:1;
190 	__u8			bind_address_no_port:1;
191 	__u8			rcv_tos;
192 	__u8			convert_csum;
193 	int			uc_index;
194 	int			mc_index;
195 	__be32			mc_addr;
196 	struct ip_mc_socklist __rcu	*mc_list;
197 	struct inet_cork_full	cork;
198 };
199 
200 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
201 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
202 
203 /* cmsg flags for inet */
204 #define IP_CMSG_PKTINFO		BIT(0)
205 #define IP_CMSG_TTL		BIT(1)
206 #define IP_CMSG_TOS		BIT(2)
207 #define IP_CMSG_RECVOPTS	BIT(3)
208 #define IP_CMSG_RETOPTS		BIT(4)
209 #define IP_CMSG_PASSSEC		BIT(5)
210 #define IP_CMSG_ORIGDSTADDR	BIT(6)
211 #define IP_CMSG_CHECKSUM	BIT(7)
212 
213 static inline struct inet_sock *inet_sk(const struct sock *sk)
214 {
215 	return (struct inet_sock *)sk;
216 }
217 
218 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
219 					     const struct sock *sk_from,
220 					     const int ancestor_size)
221 {
222 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
223 	       sk_from->sk_prot->obj_size - ancestor_size);
224 }
225 #if !(IS_ENABLED(CONFIG_IPV6))
226 static inline void inet_sk_copy_descendant(struct sock *sk_to,
227 					   const struct sock *sk_from)
228 {
229 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
230 }
231 #endif
232 
233 int inet_sk_rebuild_header(struct sock *sk);
234 
235 static inline unsigned int __inet_ehashfn(const __be32 laddr,
236 					  const __u16 lport,
237 					  const __be32 faddr,
238 					  const __be16 fport,
239 					  u32 initval)
240 {
241 	return jhash_3words((__force __u32) laddr,
242 			    (__force __u32) faddr,
243 			    ((__u32) lport) << 16 | (__force __u32)fport,
244 			    initval);
245 }
246 
247 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
248 				      struct sock *sk_listener);
249 
250 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
251 {
252 	__u8 flags = 0;
253 
254 	if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
255 		flags |= FLOWI_FLAG_ANYSRC;
256 	return flags;
257 }
258 
259 static inline void inet_inc_convert_csum(struct sock *sk)
260 {
261 	inet_sk(sk)->convert_csum++;
262 }
263 
264 static inline void inet_dec_convert_csum(struct sock *sk)
265 {
266 	if (inet_sk(sk)->convert_csum > 0)
267 		inet_sk(sk)->convert_csum--;
268 }
269 
270 static inline bool inet_get_convert_csum(struct sock *sk)
271 {
272 	return !!inet_sk(sk)->convert_csum;
273 }
274 
275 #endif	/* _INET_SOCK_H */
276