xref: /linux-6.15/include/linux/net.h (revision c506c96b)
1 /*
2  * NET		An implementation of the SOCKET network access protocol.
3  *		This is the master header file for the Linux NET layer,
4  *		or, in plain English: the networking handling part of the
5  *		kernel.
6  *
7  * Version:	@(#)net.h	1.0.3	05/25/93
8  *
9  * Authors:	Orest Zborowski, <[email protected]>
10  *		Ross Biro
11  *		Fred N. van Kempen, <[email protected]>
12  *
13  *		This program is free software; you can redistribute it and/or
14  *		modify it under the terms of the GNU General Public License
15  *		as published by the Free Software Foundation; either version
16  *		2 of the License, or (at your option) any later version.
17  */
18 #ifndef _LINUX_NET_H
19 #define _LINUX_NET_H
20 
21 #include <linux/stringify.h>
22 #include <linux/random.h>
23 #include <linux/wait.h>
24 #include <linux/fcntl.h>	/* For O_CLOEXEC and O_NONBLOCK */
25 #include <linux/kmemcheck.h>
26 #include <linux/rcupdate.h>
27 #include <linux/jump_label.h>
28 #include <uapi/linux/net.h>
29 
30 struct poll_table_struct;
31 struct pipe_inode_info;
32 struct inode;
33 struct file;
34 struct net;
35 
36 #define SOCK_ASYNC_NOSPACE	0
37 #define SOCK_ASYNC_WAITDATA	1
38 #define SOCK_NOSPACE		2
39 #define SOCK_PASSCRED		3
40 #define SOCK_PASSSEC		4
41 #define SOCK_EXTERNALLY_ALLOCATED 5
42 
43 #ifndef ARCH_HAS_SOCKET_TYPES
44 /**
45  * enum sock_type - Socket types
46  * @SOCK_STREAM: stream (connection) socket
47  * @SOCK_DGRAM: datagram (conn.less) socket
48  * @SOCK_RAW: raw socket
49  * @SOCK_RDM: reliably-delivered message
50  * @SOCK_SEQPACKET: sequential packet socket
51  * @SOCK_DCCP: Datagram Congestion Control Protocol socket
52  * @SOCK_PACKET: linux specific way of getting packets at the dev level.
53  *		  For writing rarp and other similar things on the user level.
54  *
55  * When adding some new socket type please
56  * grep ARCH_HAS_SOCKET_TYPE include/asm-* /socket.h, at least MIPS
57  * overrides this enum for binary compat reasons.
58  */
59 enum sock_type {
60 	SOCK_STREAM	= 1,
61 	SOCK_DGRAM	= 2,
62 	SOCK_RAW	= 3,
63 	SOCK_RDM	= 4,
64 	SOCK_SEQPACKET	= 5,
65 	SOCK_DCCP	= 6,
66 	SOCK_PACKET	= 10,
67 };
68 
69 #define SOCK_MAX (SOCK_PACKET + 1)
70 /* Mask which covers at least up to SOCK_MASK-1.  The
71  * remaining bits are used as flags. */
72 #define SOCK_TYPE_MASK 0xf
73 
74 /* Flags for socket, socketpair, accept4 */
75 #define SOCK_CLOEXEC	O_CLOEXEC
76 #ifndef SOCK_NONBLOCK
77 #define SOCK_NONBLOCK	O_NONBLOCK
78 #endif
79 
80 #endif /* ARCH_HAS_SOCKET_TYPES */
81 
82 enum sock_shutdown_cmd {
83 	SHUT_RD,
84 	SHUT_WR,
85 	SHUT_RDWR,
86 };
87 
88 struct socket_wq {
89 	/* Note: wait MUST be first field of socket_wq */
90 	wait_queue_head_t	wait;
91 	struct fasync_struct	*fasync_list;
92 	struct rcu_head		rcu;
93 } ____cacheline_aligned_in_smp;
94 
95 /**
96  *  struct socket - general BSD socket
97  *  @state: socket state (%SS_CONNECTED, etc)
98  *  @type: socket type (%SOCK_STREAM, etc)
99  *  @flags: socket flags (%SOCK_ASYNC_NOSPACE, etc)
100  *  @ops: protocol specific socket operations
101  *  @file: File back pointer for gc
102  *  @sk: internal networking protocol agnostic socket representation
103  *  @wq: wait queue for several uses
104  */
105 struct socket {
106 	socket_state		state;
107 
108 	kmemcheck_bitfield_begin(type);
109 	short			type;
110 	kmemcheck_bitfield_end(type);
111 
112 	unsigned long		flags;
113 
114 	struct socket_wq __rcu	*wq;
115 
116 	struct file		*file;
117 	struct sock		*sk;
118 	const struct proto_ops	*ops;
119 };
120 
121 struct vm_area_struct;
122 struct page;
123 struct kiocb;
124 struct sockaddr;
125 struct msghdr;
126 struct module;
127 
128 struct proto_ops {
129 	int		family;
130 	struct module	*owner;
131 	int		(*release)   (struct socket *sock);
132 	int		(*bind)	     (struct socket *sock,
133 				      struct sockaddr *myaddr,
134 				      int sockaddr_len);
135 	int		(*connect)   (struct socket *sock,
136 				      struct sockaddr *vaddr,
137 				      int sockaddr_len, int flags);
138 	int		(*socketpair)(struct socket *sock1,
139 				      struct socket *sock2);
140 	int		(*accept)    (struct socket *sock,
141 				      struct socket *newsock, int flags);
142 	int		(*getname)   (struct socket *sock,
143 				      struct sockaddr *addr,
144 				      int *sockaddr_len, int peer);
145 	unsigned int	(*poll)	     (struct file *file, struct socket *sock,
146 				      struct poll_table_struct *wait);
147 	int		(*ioctl)     (struct socket *sock, unsigned int cmd,
148 				      unsigned long arg);
149 #ifdef CONFIG_COMPAT
150 	int	 	(*compat_ioctl) (struct socket *sock, unsigned int cmd,
151 				      unsigned long arg);
152 #endif
153 	int		(*listen)    (struct socket *sock, int len);
154 	int		(*shutdown)  (struct socket *sock, int flags);
155 	int		(*setsockopt)(struct socket *sock, int level,
156 				      int optname, char __user *optval, unsigned int optlen);
157 	int		(*getsockopt)(struct socket *sock, int level,
158 				      int optname, char __user *optval, int __user *optlen);
159 #ifdef CONFIG_COMPAT
160 	int		(*compat_setsockopt)(struct socket *sock, int level,
161 				      int optname, char __user *optval, unsigned int optlen);
162 	int		(*compat_getsockopt)(struct socket *sock, int level,
163 				      int optname, char __user *optval, int __user *optlen);
164 #endif
165 	int		(*sendmsg)   (struct kiocb *iocb, struct socket *sock,
166 				      struct msghdr *m, size_t total_len);
167 	int		(*recvmsg)   (struct kiocb *iocb, struct socket *sock,
168 				      struct msghdr *m, size_t total_len,
169 				      int flags);
170 	int		(*mmap)	     (struct file *file, struct socket *sock,
171 				      struct vm_area_struct * vma);
172 	ssize_t		(*sendpage)  (struct socket *sock, struct page *page,
173 				      int offset, size_t size, int flags);
174 	ssize_t 	(*splice_read)(struct socket *sock,  loff_t *ppos,
175 				       struct pipe_inode_info *pipe, size_t len, unsigned int flags);
176 	void		(*set_peek_off)(struct sock *sk, int val);
177 };
178 
179 #define DECLARE_SOCKADDR(type, dst, src)	\
180 	type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
181 
182 struct net_proto_family {
183 	int		family;
184 	int		(*create)(struct net *net, struct socket *sock,
185 				  int protocol, int kern);
186 	struct module	*owner;
187 };
188 
189 struct iovec;
190 struct kvec;
191 
192 enum {
193 	SOCK_WAKE_IO,
194 	SOCK_WAKE_WAITD,
195 	SOCK_WAKE_SPACE,
196 	SOCK_WAKE_URG,
197 };
198 
199 int sock_wake_async(struct socket *sk, int how, int band);
200 int sock_register(const struct net_proto_family *fam);
201 void sock_unregister(int family);
202 int __sock_create(struct net *net, int family, int type, int proto,
203 		  struct socket **res, int kern);
204 int sock_create(int family, int type, int proto, struct socket **res);
205 int sock_create_kern(int family, int type, int proto, struct socket **res);
206 int sock_create_lite(int family, int type, int proto, struct socket **res);
207 void sock_release(struct socket *sock);
208 int sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t len);
209 int sock_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
210 		 int flags);
211 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname);
212 struct socket *sockfd_lookup(int fd, int *err);
213 struct socket *sock_from_file(struct file *file, int *err);
214 #define		     sockfd_put(sock) fput(sock->file)
215 int net_ratelimit(void);
216 
217 #define net_ratelimited_function(function, ...)			\
218 do {								\
219 	if (net_ratelimit())					\
220 		function(__VA_ARGS__);				\
221 } while (0)
222 
223 #define net_emerg_ratelimited(fmt, ...)				\
224 	net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
225 #define net_alert_ratelimited(fmt, ...)				\
226 	net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
227 #define net_crit_ratelimited(fmt, ...)				\
228 	net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
229 #define net_err_ratelimited(fmt, ...)				\
230 	net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
231 #define net_notice_ratelimited(fmt, ...)			\
232 	net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
233 #define net_warn_ratelimited(fmt, ...)				\
234 	net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
235 #define net_info_ratelimited(fmt, ...)				\
236 	net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
237 #define net_dbg_ratelimited(fmt, ...)				\
238 	net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
239 
240 #define net_random()		prandom_u32()
241 #define net_srandom(seed)	prandom_seed((__force u32)(seed))
242 
243 bool __net_get_random_once(void *buf, int nbytes, bool *done,
244 			   struct static_key *done_key);
245 
246 #ifdef HAVE_JUMP_LABEL
247 #define ___NET_RANDOM_STATIC_KEY_INIT ((struct static_key) \
248 		{ .enabled = ATOMIC_INIT(0), .entries = (void *)1 })
249 #else /* !HAVE_JUMP_LABEL */
250 #define ___NET_RANDOM_STATIC_KEY_INIT STATIC_KEY_INIT_FALSE
251 #endif /* HAVE_JUMP_LABEL */
252 
253 #define net_get_random_once(buf, nbytes)				\
254 	({								\
255 		bool ___ret = false;					\
256 		static bool ___done = false;				\
257 		static struct static_key ___done_key =			\
258 			___NET_RANDOM_STATIC_KEY_INIT;			\
259 		if (!static_key_true(&___done_key))			\
260 			___ret = __net_get_random_once(buf,		\
261 						       nbytes,		\
262 						       &___done,	\
263 						       &___done_key);	\
264 		___ret;							\
265 	})
266 
267 int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
268 		   size_t num, size_t len);
269 int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
270 		   size_t num, size_t len, int flags);
271 
272 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen);
273 int kernel_listen(struct socket *sock, int backlog);
274 int kernel_accept(struct socket *sock, struct socket **newsock, int flags);
275 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
276 		   int flags);
277 int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
278 		       int *addrlen);
279 int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
280 		       int *addrlen);
281 int kernel_getsockopt(struct socket *sock, int level, int optname, char *optval,
282 		      int *optlen);
283 int kernel_setsockopt(struct socket *sock, int level, int optname, char *optval,
284 		      unsigned int optlen);
285 int kernel_sendpage(struct socket *sock, struct page *page, int offset,
286 		    size_t size, int flags);
287 int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg);
288 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
289 
290 #define MODULE_ALIAS_NETPROTO(proto) \
291 	MODULE_ALIAS("net-pf-" __stringify(proto))
292 
293 #define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
294 	MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
295 
296 #define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
297 	MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
298 		     "-type-" __stringify(type))
299 
300 #define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
301 	MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
302 		     name)
303 #endif	/* _LINUX_NET_H */
304