xref: /openbmc/linux/include/net/inet_sock.h (revision 4f6cce39)
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 #if IS_ENABLED(CONFIG_IPV6)
101 		struct {
102 			struct ipv6_txoptions	*ipv6_opt;
103 			struct sk_buff		*pktopts;
104 		};
105 #endif
106 	};
107 };
108 
109 static inline struct inet_request_sock *inet_rsk(const struct request_sock *sk)
110 {
111 	return (struct inet_request_sock *)sk;
112 }
113 
114 static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
115 {
116 	if (!sk->sk_mark && sock_net(sk)->ipv4.sysctl_tcp_fwmark_accept)
117 		return skb->mark;
118 
119 	return sk->sk_mark;
120 }
121 
122 static inline int inet_request_bound_dev_if(const struct sock *sk,
123 					    struct sk_buff *skb)
124 {
125 #ifdef CONFIG_NET_L3_MASTER_DEV
126 	struct net *net = sock_net(sk);
127 
128 	if (!sk->sk_bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept)
129 		return l3mdev_master_ifindex_by_index(net, skb->skb_iif);
130 #endif
131 
132 	return sk->sk_bound_dev_if;
133 }
134 
135 struct inet_cork {
136 	unsigned int		flags;
137 	__be32			addr;
138 	struct ip_options	*opt;
139 	unsigned int		fragsize;
140 	int			length; /* Total length of all frames */
141 	struct dst_entry	*dst;
142 	u8			tx_flags;
143 	__u8			ttl;
144 	__s16			tos;
145 	char			priority;
146 };
147 
148 struct inet_cork_full {
149 	struct inet_cork	base;
150 	struct flowi		fl;
151 };
152 
153 struct ip_mc_socklist;
154 struct ipv6_pinfo;
155 struct rtable;
156 
157 /** struct inet_sock - representation of INET sockets
158  *
159  * @sk - ancestor class
160  * @pinet6 - pointer to IPv6 control block
161  * @inet_daddr - Foreign IPv4 addr
162  * @inet_rcv_saddr - Bound local IPv4 addr
163  * @inet_dport - Destination port
164  * @inet_num - Local port
165  * @inet_saddr - Sending source
166  * @uc_ttl - Unicast TTL
167  * @inet_sport - Source port
168  * @inet_id - ID counter for DF pkts
169  * @tos - TOS
170  * @mc_ttl - Multicasting TTL
171  * @is_icsk - is this an inet_connection_sock?
172  * @uc_index - Unicast outgoing device index
173  * @mc_index - Multicast device index
174  * @mc_list - Group array
175  * @cork - info to build ip hdr on each ip frag while socket is corked
176  */
177 struct inet_sock {
178 	/* sk and pinet6 has to be the first two members of inet_sock */
179 	struct sock		sk;
180 #if IS_ENABLED(CONFIG_IPV6)
181 	struct ipv6_pinfo	*pinet6;
182 #endif
183 	/* Socket demultiplex comparisons on incoming packets. */
184 #define inet_daddr		sk.__sk_common.skc_daddr
185 #define inet_rcv_saddr		sk.__sk_common.skc_rcv_saddr
186 #define inet_dport		sk.__sk_common.skc_dport
187 #define inet_num		sk.__sk_common.skc_num
188 
189 	__be32			inet_saddr;
190 	__s16			uc_ttl;
191 	__u16			cmsg_flags;
192 	__be16			inet_sport;
193 	__u16			inet_id;
194 
195 	struct ip_options_rcu __rcu	*inet_opt;
196 	int			rx_dst_ifindex;
197 	__u8			tos;
198 	__u8			min_ttl;
199 	__u8			mc_ttl;
200 	__u8			pmtudisc;
201 	__u8			recverr:1,
202 				is_icsk:1,
203 				freebind:1,
204 				hdrincl:1,
205 				mc_loop:1,
206 				transparent:1,
207 				mc_all:1,
208 				nodefrag:1;
209 	__u8			bind_address_no_port:1,
210 				defer_connect:1; /* Indicates that fastopen_connect is set
211 						  * and cookie exists so we defer connect
212 						  * until first data frame is written
213 						  */
214 	__u8			rcv_tos;
215 	__u8			convert_csum;
216 	int			uc_index;
217 	int			mc_index;
218 	__be32			mc_addr;
219 	struct ip_mc_socklist __rcu	*mc_list;
220 	struct inet_cork_full	cork;
221 };
222 
223 #define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
224 #define IPCORK_ALLFRAG	2	/* always fragment (for ipv6 for now) */
225 
226 /* cmsg flags for inet */
227 #define IP_CMSG_PKTINFO		BIT(0)
228 #define IP_CMSG_TTL		BIT(1)
229 #define IP_CMSG_TOS		BIT(2)
230 #define IP_CMSG_RECVOPTS	BIT(3)
231 #define IP_CMSG_RETOPTS		BIT(4)
232 #define IP_CMSG_PASSSEC		BIT(5)
233 #define IP_CMSG_ORIGDSTADDR	BIT(6)
234 #define IP_CMSG_CHECKSUM	BIT(7)
235 #define IP_CMSG_RECVFRAGSIZE	BIT(8)
236 
237 /**
238  * sk_to_full_sk - Access to a full socket
239  * @sk: pointer to a socket
240  *
241  * SYNACK messages might be attached to request sockets.
242  * Some places want to reach the listener in this case.
243  */
244 static inline struct sock *sk_to_full_sk(struct sock *sk)
245 {
246 #ifdef CONFIG_INET
247 	if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
248 		sk = inet_reqsk(sk)->rsk_listener;
249 #endif
250 	return sk;
251 }
252 
253 /* sk_to_full_sk() variant with a const argument */
254 static inline const struct sock *sk_const_to_full_sk(const struct sock *sk)
255 {
256 #ifdef CONFIG_INET
257 	if (sk && sk->sk_state == TCP_NEW_SYN_RECV)
258 		sk = ((const struct request_sock *)sk)->rsk_listener;
259 #endif
260 	return sk;
261 }
262 
263 static inline struct sock *skb_to_full_sk(const struct sk_buff *skb)
264 {
265 	return sk_to_full_sk(skb->sk);
266 }
267 
268 static inline struct inet_sock *inet_sk(const struct sock *sk)
269 {
270 	return (struct inet_sock *)sk;
271 }
272 
273 static inline void __inet_sk_copy_descendant(struct sock *sk_to,
274 					     const struct sock *sk_from,
275 					     const int ancestor_size)
276 {
277 	memcpy(inet_sk(sk_to) + 1, inet_sk(sk_from) + 1,
278 	       sk_from->sk_prot->obj_size - ancestor_size);
279 }
280 #if !(IS_ENABLED(CONFIG_IPV6))
281 static inline void inet_sk_copy_descendant(struct sock *sk_to,
282 					   const struct sock *sk_from)
283 {
284 	__inet_sk_copy_descendant(sk_to, sk_from, sizeof(struct inet_sock));
285 }
286 #endif
287 
288 int inet_sk_rebuild_header(struct sock *sk);
289 
290 static inline unsigned int __inet_ehashfn(const __be32 laddr,
291 					  const __u16 lport,
292 					  const __be32 faddr,
293 					  const __be16 fport,
294 					  u32 initval)
295 {
296 	return jhash_3words((__force __u32) laddr,
297 			    (__force __u32) faddr,
298 			    ((__u32) lport) << 16 | (__force __u32)fport,
299 			    initval);
300 }
301 
302 struct request_sock *inet_reqsk_alloc(const struct request_sock_ops *ops,
303 				      struct sock *sk_listener,
304 				      bool attach_listener);
305 
306 static inline __u8 inet_sk_flowi_flags(const struct sock *sk)
307 {
308 	__u8 flags = 0;
309 
310 	if (inet_sk(sk)->transparent || inet_sk(sk)->hdrincl)
311 		flags |= FLOWI_FLAG_ANYSRC;
312 	return flags;
313 }
314 
315 static inline void inet_inc_convert_csum(struct sock *sk)
316 {
317 	inet_sk(sk)->convert_csum++;
318 }
319 
320 static inline void inet_dec_convert_csum(struct sock *sk)
321 {
322 	if (inet_sk(sk)->convert_csum > 0)
323 		inet_sk(sk)->convert_csum--;
324 }
325 
326 static inline bool inet_get_convert_csum(struct sock *sk)
327 {
328 	return !!inet_sk(sk)->convert_csum;
329 }
330 
331 #endif	/* _INET_SOCK_H */
332