xref: /openbmc/linux/include/net/inet_sock.h (revision a06c488d)
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 #include <net/l3mdev.h>
32 
33 /** struct ip_options - IP Options
34  *
35  * @faddr - Saved first hop address
36  * @nexthop - Saved nexthop address in LSRR and SSRR
37  * @is_strictroute - Strict source route
38  * @srr_is_hit - Packet destination addr was our one
39  * @is_changed - IP checksum more not valid
40  * @rr_needaddr - Need to record addr of outgoing dev
41  * @ts_needtime - Need to record timestamp
42  * @ts_needaddr - Need to record addr of outgoing dev
43  */
44 struct ip_options {
45 	__be32		faddr;
46 	__be32		nexthop;
47 	unsigned char	optlen;
48 	unsigned char	srr;
49 	unsigned char	rr;
50 	unsigned char	ts;
51 	unsigned char	is_strictroute:1,
52 			srr_is_hit:1,
53 			is_changed:1,
54 			rr_needaddr:1,
55 			ts_needtime:1,
56 			ts_needaddr:1;
57 	unsigned char	router_alert;
58 	unsigned char	cipso;
59 	unsigned char	__pad2;
60 	unsigned char	__data[0];
61 };
62 
63 struct ip_options_rcu {
64 	struct rcu_head rcu;
65 	struct ip_options opt;
66 };
67 
68 struct ip_options_data {
69 	struct ip_options_rcu	opt;
70 	char			data[40];
71 };
72 
73 struct inet_request_sock {
74 	struct request_sock	req;
75 #define ir_loc_addr		req.__req_common.skc_rcv_saddr
76 #define ir_rmt_addr		req.__req_common.skc_daddr
77 #define ir_num			req.__req_common.skc_num
78 #define ir_rmt_port		req.__req_common.skc_dport
79 #define ir_v6_rmt_addr		req.__req_common.skc_v6_daddr
80 #define ir_v6_loc_addr		req.__req_common.skc_v6_rcv_saddr
81 #define ir_iif			req.__req_common.skc_bound_dev_if
82 #define ir_cookie		req.__req_common.skc_cookie
83 #define ireq_net		req.__req_common.skc_net
84 #define ireq_state		req.__req_common.skc_state
85 #define ireq_family		req.__req_common.skc_family
86 
87 	kmemcheck_bitfield_begin(flags);
88 	u16			snd_wscale : 4,
89 				rcv_wscale : 4,
90 				tstamp_ok  : 1,
91 				sack_ok	   : 1,
92 				wscale_ok  : 1,
93 				ecn_ok	   : 1,
94 				acked	   : 1,
95 				no_srccheck: 1;
96 	kmemcheck_bitfield_end(flags);
97 	u32                     ir_mark;
98 	union {
99 		struct ip_options_rcu	*opt;
100 		struct sk_buff		*pktopts;
101 	};
102 };
103 
104 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
105 {
106 	return (struct inet_request_sock *)sk;
107 }
108 
109 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
110 {
111 	if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
112 		return skb->mark;
113 
114 	return sk->sk_mark;
115 }
116 
117 static inline int inet_request_bound_dev_if(const struct sock *sk,
118 					    struct sk_buff *skb)
119 {
120 #ifdef CONFIG_NET_L3_MASTER_DEV
121 	struct net *net = sock_net(sk);
122 
123 	if (!sk->sk_bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept)
124 		return l3mdev_master_ifindex_by_index(net, skb->skb_iif);
125 #endif
126 
127 	return sk->sk_bound_dev_if;
128 }
129 
130 struct inet_cork {
131 	unsigned int		flags;
132 	__be32			addr;
133 	struct ip_options	*opt;
134 	unsigned int		fragsize;
135 	int			length; /* Total length of all frames */
136 	struct dst_entry	*dst;
137 	u8			tx_flags;
138 	__u8			ttl;
139 	__s16			tos;
140 	char			priority;
141 };
142 
143 struct inet_cork_full {
144 	struct inet_cork	base;
145 	struct flowi		fl;
146 };
147 
148 struct ip_mc_socklist;
149 struct ipv6_pinfo;
150 struct rtable;
151 
152 /** struct inet_sock - representation of INET sockets
153  *
154  * @sk - ancestor class
155  * @pinet6 - pointer to IPv6 control block
156  * @inet_daddr - Foreign IPv4 addr
157  * @inet_rcv_saddr - Bound local IPv4 addr
158  * @inet_dport - Destination port
159  * @inet_num - Local port
160  * @inet_saddr - Sending source
161  * @uc_ttl - Unicast TTL
162  * @inet_sport - Source port
163  * @inet_id - ID counter for DF pkts
164  * @tos - TOS
165  * @mc_ttl - Multicasting TTL
166  * @is_icsk - is this an inet_connection_sock?
167  * @uc_index - Unicast outgoing device index
168  * @mc_index - Multicast device index
169  * @mc_list - Group array
170  * @cork - info to build ip hdr on each ip frag while socket is corked
171  */
172 struct inet_sock {
173 	/* sk and pinet6 has to be the first two members of inet_sock */
174 	struct sock		sk;
175 #if IS_ENABLED(CONFIG_IPV6)
176 	struct ipv6_pinfo	*pinet6;
177 #endif
178 	/* Socket demultiplex comparisons on incoming packets. */
179 #define inet_daddr		sk.__sk_common.skc_daddr
180 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
181 #define inet_dport		sk.__sk_common.skc_dport
182 #define inet_num		sk.__sk_common.skc_num
183 
184 	__be32			inet_saddr;
185 	__s16			uc_ttl;
186 	__u16			cmsg_flags;
187 	__be16			inet_sport;
188 	__u16			inet_id;
189 
190 	struct ip_options_rcu __rcu	*inet_opt;
191 	int			rx_dst_ifindex;
192 	__u8			tos;
193 	__u8			min_ttl;
194 	__u8			mc_ttl;
195 	__u8			pmtudisc;
196 	__u8			recverr:1,
197 				is_icsk:1,
198 				freebind:1,
199 				hdrincl:1,
200 				mc_loop:1,
201 				transparent:1,
202 				mc_all:1,
203 				nodefrag:1;
204 	__u8			bind_address_no_port:1;
205 	__u8			rcv_tos;
206 	__u8			convert_csum;
207 	int			uc_index;
208 	int			mc_index;
209 	__be32			mc_addr;
210 	struct ip_mc_socklist __rcu	*mc_list;
211 	struct inet_cork_full	cork;
212 };
213 
214 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
215 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
216 
217 /* cmsg flags for inet */
218 #define IP_CMSG_PKTINFO		BIT(0)
219 #define IP_CMSG_TTL		BIT(1)
220 #define IP_CMSG_TOS		BIT(2)
221 #define IP_CMSG_RECVOPTS	BIT(3)
222 #define IP_CMSG_RETOPTS		BIT(4)
223 #define IP_CMSG_PASSSEC		BIT(5)
224 #define IP_CMSG_ORIGDSTADDR	BIT(6)
225 #define IP_CMSG_CHECKSUM	BIT(7)
226 
227 /**
228  * sk_to_full_sk - Access to a full socket
229  * @sk: pointer to a socket
230  *
231  * SYNACK messages might be attached to request sockets.
232  * Some places want to reach the listener in this case.
233  */
234 static inline struct sock *sk_to_full_sk(struct sock *sk)
235 {
236 #ifdef CONFIG_INET
237 	if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
238 		sk = inet_reqsk(sk)->rsk_listener;
239 #endif
240 	return sk;
241 }
242 
243 /* sk_to_full_sk() variant with a const argument */
244 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk)
245 {
246 #ifdef CONFIG_INET
247 	if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
248 		sk = ((const struct request_sock *)sk)->rsk_listener;
249 #endif
250 	return sk;
251 }
252 
253 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
254 {
255 	return sk_to_full_sk(skb->sk);
256 }
257 
258 static inline struct inet_sock *inet_sk(const struct sock *sk)
259 {
260 	return (struct inet_sock *)sk;
261 }
262 
263 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
264 					     const struct sock *sk_from,
265 					     const int ancestor_size)
266 {
267 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
268 	       sk_from->sk_prot->obj_size - ancestor_size);
269 }
270 #if !(IS_ENABLED(CONFIG_IPV6))
271 static inline void inet_sk_copy_descendant(struct sock *sk_to,
272 					   const struct sock *sk_from)
273 {
274 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
275 }
276 #endif
277 
278 int inet_sk_rebuild_header(struct sock *sk);
279 
280 static inline unsigned int __inet_ehashfn(const __be32 laddr,
281 					  const __u16 lport,
282 					  const __be32 faddr,
283 					  const __be16 fport,
284 					  u32 initval)
285 {
286 	return jhash_3words((__force __u32) laddr,
287 			    (__force __u32) faddr,
288 			    ((__u32) lport) << 16 | (__force __u32)fport,
289 			    initval);
290 }
291 
292 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
293 				      struct sock *sk_listener,
294 				      bool attach_listener);
295 
296 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
297 {
298 	__u8 flags = 0;
299 
300 	if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
301 		flags |= FLOWI_FLAG_ANYSRC;
302 	return flags;
303 }
304 
305 static inline void inet_inc_convert_csum(struct sock *sk)
306 {
307 	inet_sk(sk)->convert_csum++;
308 }
309 
310 static inline void inet_dec_convert_csum(struct sock *sk)
311 {
312 	if (inet_sk(sk)->convert_csum > 0)
313 		inet_sk(sk)->convert_csum--;
314 }
315 
316 static inline bool inet_get_convert_csum(struct sock *sk)
317 {
318 	return !!inet_sk(sk)->convert_csum;
319 }
320 
321 #endif	/* _INET_SOCK_H */
322