xref: /linux/include/linux/socket.h (revision 24f171c7e145f43b9f187578e89b0982ce87e54c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SOCKET_H
3 #define _LINUX_SOCKET_H
4 
5 
6 #include <asm/socket.h>			/* arch-dependent defines	*/
7 #include <linux/sockios.h>		/* the SIOCxxx I/O controls	*/
8 #include <linux/uio.h>			/* iovec support		*/
9 #include <linux/types.h>		/* pid_t			*/
10 #include <linux/compiler.h>		/* __user			*/
11 #include <uapi/linux/socket.h>
12 
13 struct file;
14 struct pid;
15 struct cred;
16 struct socket;
17 struct sock;
18 struct sk_buff;
19 struct proto_accept_arg;
20 
21 #define __sockaddr_check_size(size)	\
22 	BUILD_BUG_ON(((size) > sizeof(struct __kernel_sockaddr_storage)))
23 
24 #ifdef CONFIG_PROC_FS
25 struct seq_file;
26 extern void socket_seq_show(struct seq_file *seq);
27 #endif
28 
29 typedef __kernel_sa_family_t	sa_family_t;
30 
31 /*
32  *	1003.1g requires sa_family_t and that sa_data is char.
33  */
34 
35 /* Deprecated for in-kernel use. Use struct sockaddr_unsized instead. */
36 struct sockaddr {
37 	sa_family_t	sa_family;	/* address family, AF_xxx	*/
38 	char		sa_data[14];	/* 14 bytes of protocol address	*/
39 };
40 
41 /**
42  * struct sockaddr_unsized - Unspecified size sockaddr for callbacks
43  * @sa_family: Address family (AF_UNIX, AF_INET, AF_INET6, etc.)
44  * @sa_data: Flexible array for address data
45  *
46  * This structure is designed for callback interfaces where the
47  * total size is known via the sockaddr_len parameter. Unlike struct
48  * sockaddr which has a fixed 14-byte sa_data limit or struct
49  * sockaddr_storage which has a fixed 128-byte sa_data limit, this
50  * structure can accommodate addresses of any size, but must be used
51  * carefully.
52  */
53 struct sockaddr_unsized {
54 	__kernel_sa_family_t	sa_family;	/* address family, AF_xxx */
55 	char			sa_data[];	/* flexible address data */
56 };
57 
58 struct linger {
59 	int		l_onoff;	/* Linger active		*/
60 	int		l_linger;	/* How long to linger for	*/
61 };
62 
63 #define sockaddr_storage __kernel_sockaddr_storage
64 
65 /*
66  *	As we do 4.4BSD message passing we use a 4.4BSD message passing
67  *	system, not 4.3. Thus msg_accrights(len) are now missing. They
68  *	belong in an obscure libc emulation or the bin.
69  */
70 
71 struct msghdr {
72 	void		*msg_name;	/* ptr to socket address structure */
73 	int		msg_namelen;	/* size of socket address structure */
74 
75 	int		msg_inq;	/* output, data left in socket */
76 
77 	struct iov_iter	msg_iter;	/* data */
78 
79 	/*
80 	 * Ancillary data. msg_control_user is the user buffer used for the
81 	 * recv* side when msg_control_is_user is set, msg_control is the kernel
82 	 * buffer used for all other cases.
83 	 */
84 	union {
85 		void		*msg_control;
86 		void __user	*msg_control_user;
87 	};
88 	bool		msg_control_is_user : 1;
89 	bool		msg_get_inq : 1;/* return INQ after receive */
90 	unsigned int	msg_flags;	/* flags on received message */
91 	__kernel_size_t	msg_controllen;	/* ancillary data buffer length */
92 	struct kiocb	*msg_iocb;	/* ptr to iocb for async requests */
93 	struct ubuf_info *msg_ubuf;
94 	int (*sg_from_iter)(struct sk_buff *skb,
95 			    struct iov_iter *from, size_t length);
96 };
97 
98 struct user_msghdr {
99 	void		__user *msg_name;	/* ptr to socket address structure */
100 	int		msg_namelen;		/* size of socket address structure */
101 	struct iovec	__user *msg_iov;	/* scatter/gather array */
102 	__kernel_size_t	msg_iovlen;		/* # elements in msg_iov */
103 	void		__user *msg_control;	/* ancillary data */
104 	__kernel_size_t	msg_controllen;		/* ancillary data buffer length */
105 	unsigned int	msg_flags;		/* flags on received message */
106 };
107 
108 /* For recvmmsg/sendmmsg */
109 struct mmsghdr {
110 	struct user_msghdr  msg_hdr;
111 	unsigned int        msg_len;
112 };
113 
114 /*
115  *	POSIX 1003.1g - ancillary data object information
116  *	Ancillary data consists of a sequence of pairs of
117  *	(cmsghdr, cmsg_data[])
118  */
119 
120 struct cmsghdr {
121 	__kernel_size_t	cmsg_len;	/* data byte count, including hdr */
122         int		cmsg_level;	/* originating protocol */
123         int		cmsg_type;	/* protocol-specific type */
124 };
125 
126 /*
127  *	Ancillary data object information MACROS
128  *	Table 5-14 of POSIX 1003.1g
129  */
130 
131 #define __CMSG_NXTHDR(ctl, len, cmsg) __cmsg_nxthdr((ctl),(len),(cmsg))
132 #define CMSG_NXTHDR(mhdr, cmsg) cmsg_nxthdr((mhdr), (cmsg))
133 
134 #define CMSG_ALIGN(len) ( ((len)+sizeof(long)-1) & ~(sizeof(long)-1) )
135 
136 #define CMSG_DATA(cmsg) \
137 	((void *)(cmsg) + sizeof(struct cmsghdr))
138 #define CMSG_USER_DATA(cmsg) \
139 	((void __user *)(cmsg) + sizeof(struct cmsghdr))
140 #define CMSG_SPACE(len) (sizeof(struct cmsghdr) + CMSG_ALIGN(len))
141 #define CMSG_LEN(len) (sizeof(struct cmsghdr) + (len))
142 
143 #define __CMSG_FIRSTHDR(ctl,len) ((len) >= sizeof(struct cmsghdr) ? \
144 				  (struct cmsghdr *)(ctl) : \
145 				  (struct cmsghdr *)NULL)
146 #define CMSG_FIRSTHDR(msg)	__CMSG_FIRSTHDR((msg)->msg_control, (msg)->msg_controllen)
147 #define CMSG_OK(mhdr, cmsg) ((cmsg)->cmsg_len >= sizeof(struct cmsghdr) && \
148 			     (cmsg)->cmsg_len <= (unsigned long) \
149 			     ((mhdr)->msg_controllen - \
150 			      ((char *)(cmsg) - (char *)(mhdr)->msg_control)))
151 #define for_each_cmsghdr(cmsg, msg) \
152 	for (cmsg = CMSG_FIRSTHDR(msg); \
153 	     cmsg; \
154 	     cmsg = CMSG_NXTHDR(msg, cmsg))
155 
156 /*
157  *	Get the next cmsg header
158  *
159  *	PLEASE, do not touch this function. If you think, that it is
160  *	incorrect, grep kernel sources and think about consequences
161  *	before trying to improve it.
162  *
163  *	Now it always returns valid, not truncated ancillary object
164  *	HEADER. But caller still MUST check, that cmsg->cmsg_len is
165  *	inside range, given by msg->msg_controllen before using
166  *	ancillary object DATA.				--ANK (980731)
167  */
168 
169 static inline struct cmsghdr * __cmsg_nxthdr(void *__ctl, __kernel_size_t __size,
170 					       struct cmsghdr *__cmsg)
171 {
172 	struct cmsghdr * __ptr;
173 
174 	__ptr = (struct cmsghdr*)(((unsigned char *) __cmsg) +  CMSG_ALIGN(__cmsg->cmsg_len));
175 	if ((unsigned long)((char*)(__ptr+1) - (char *) __ctl) > __size)
176 		return (struct cmsghdr *)0;
177 
178 	return __ptr;
179 }
180 
181 static inline struct cmsghdr * cmsg_nxthdr (struct msghdr *__msg, struct cmsghdr *__cmsg)
182 {
183 	return __cmsg_nxthdr(__msg->msg_control, __msg->msg_controllen, __cmsg);
184 }
185 
186 static inline size_t msg_data_left(const struct msghdr *msg)
187 {
188 	return iov_iter_count(&msg->msg_iter);
189 }
190 
191 /* "Socket"-level control message types: */
192 
193 #define	SCM_RIGHTS	0x01		/* rw: access rights (array of int) */
194 #define SCM_CREDENTIALS 0x02		/* rw: struct ucred		*/
195 #define SCM_SECURITY	0x03		/* rw: security label		*/
196 #define SCM_PIDFD	0x04		/* ro: pidfd (int)		*/
197 
198 struct ucred {
199 	__u32	pid;
200 	__u32	uid;
201 	__u32	gid;
202 };
203 
204 /* Supported address families. */
205 #define AF_UNSPEC	0
206 #define AF_UNIX		1	/* Unix domain sockets 		*/
207 #define AF_LOCAL	1	/* POSIX name for AF_UNIX	*/
208 #define AF_INET		2	/* Internet IP Protocol 	*/
209 #define AF_AX25		3	/* Amateur Radio AX.25 		*/
210 #define AF_IPX		4	/* Novell IPX 			*/
211 #define AF_APPLETALK	5	/* AppleTalk DDP 		*/
212 #define AF_NETROM	6	/* Amateur Radio NET/ROM 	*/
213 #define AF_BRIDGE	7	/* Multiprotocol bridge 	*/
214 #define AF_ATMPVC	8	/* ATM PVCs			*/
215 #define AF_X25		9	/* Reserved for X.25 project 	*/
216 #define AF_INET6	10	/* IP version 6			*/
217 #define AF_ROSE		11	/* Amateur Radio X.25 PLP	*/
218 #define AF_DECnet	12	/* Reserved for DECnet project	*/
219 #define AF_NETBEUI	13	/* Reserved for 802.2LLC project*/
220 #define AF_SECURITY	14	/* Security callback pseudo AF */
221 #define AF_KEY		15      /* PF_KEY key management API */
222 #define AF_NETLINK	16
223 #define AF_ROUTE	AF_NETLINK /* Alias to emulate 4.4BSD */
224 #define AF_PACKET	17	/* Packet family		*/
225 #define AF_ASH		18	/* Ash				*/
226 #define AF_ECONET	19	/* Acorn Econet			*/
227 #define AF_ATMSVC	20	/* ATM SVCs			*/
228 #define AF_RDS		21	/* RDS sockets 			*/
229 #define AF_SNA		22	/* Linux SNA Project (nutters!) */
230 #define AF_IRDA		23	/* IRDA sockets			*/
231 #define AF_PPPOX	24	/* PPPoX sockets		*/
232 #define AF_WANPIPE	25	/* Wanpipe API Sockets */
233 #define AF_LLC		26	/* Linux LLC			*/
234 #define AF_IB		27	/* Native InfiniBand address	*/
235 #define AF_MPLS		28	/* MPLS */
236 #define AF_CAN		29	/* Controller Area Network      */
237 #define AF_TIPC		30	/* TIPC sockets			*/
238 #define AF_BLUETOOTH	31	/* Bluetooth sockets 		*/
239 #define AF_IUCV		32	/* IUCV sockets			*/
240 #define AF_RXRPC	33	/* RxRPC sockets 		*/
241 #define AF_ISDN		34	/* mISDN sockets 		*/
242 #define AF_PHONET	35	/* Phonet sockets		*/
243 #define AF_IEEE802154	36	/* IEEE802154 sockets		*/
244 #define AF_CAIF		37	/* CAIF sockets			*/
245 #define AF_ALG		38	/* Algorithm sockets		*/
246 #define AF_NFC		39	/* NFC sockets			*/
247 #define AF_VSOCK	40	/* vSockets			*/
248 #define AF_KCM		41	/* Kernel Connection Multiplexor*/
249 #define AF_QIPCRTR	42	/* Qualcomm IPC Router          */
250 #define AF_SMC		43	/* smc sockets: reserve number for
251 				 * PF_SMC protocol family that
252 				 * reuses AF_INET address family
253 				 */
254 #define AF_XDP		44	/* XDP sockets			*/
255 #define AF_MCTP		45	/* Management component
256 				 * transport protocol
257 				 */
258 
259 #define AF_MAX		46	/* For now.. */
260 
261 /* Protocol families, same as address families. */
262 #define PF_UNSPEC	AF_UNSPEC
263 #define PF_UNIX		AF_UNIX
264 #define PF_LOCAL	AF_LOCAL
265 #define PF_INET		AF_INET
266 #define PF_AX25		AF_AX25
267 #define PF_IPX		AF_IPX
268 #define PF_APPLETALK	AF_APPLETALK
269 #define	PF_NETROM	AF_NETROM
270 #define PF_BRIDGE	AF_BRIDGE
271 #define PF_ATMPVC	AF_ATMPVC
272 #define PF_X25		AF_X25
273 #define PF_INET6	AF_INET6
274 #define PF_ROSE		AF_ROSE
275 #define PF_DECnet	AF_DECnet
276 #define PF_NETBEUI	AF_NETBEUI
277 #define PF_SECURITY	AF_SECURITY
278 #define PF_KEY		AF_KEY
279 #define PF_NETLINK	AF_NETLINK
280 #define PF_ROUTE	AF_ROUTE
281 #define PF_PACKET	AF_PACKET
282 #define PF_ASH		AF_ASH
283 #define PF_ECONET	AF_ECONET
284 #define PF_ATMSVC	AF_ATMSVC
285 #define PF_RDS		AF_RDS
286 #define PF_SNA		AF_SNA
287 #define PF_IRDA		AF_IRDA
288 #define PF_PPPOX	AF_PPPOX
289 #define PF_WANPIPE	AF_WANPIPE
290 #define PF_LLC		AF_LLC
291 #define PF_IB		AF_IB
292 #define PF_MPLS		AF_MPLS
293 #define PF_CAN		AF_CAN
294 #define PF_TIPC		AF_TIPC
295 #define PF_BLUETOOTH	AF_BLUETOOTH
296 #define PF_IUCV		AF_IUCV
297 #define PF_RXRPC	AF_RXRPC
298 #define PF_ISDN		AF_ISDN
299 #define PF_PHONET	AF_PHONET
300 #define PF_IEEE802154	AF_IEEE802154
301 #define PF_CAIF		AF_CAIF
302 #define PF_ALG		AF_ALG
303 #define PF_NFC		AF_NFC
304 #define PF_VSOCK	AF_VSOCK
305 #define PF_KCM		AF_KCM
306 #define PF_QIPCRTR	AF_QIPCRTR
307 #define PF_SMC		AF_SMC
308 #define PF_XDP		AF_XDP
309 #define PF_MCTP		AF_MCTP
310 #define PF_MAX		AF_MAX
311 
312 /* Maximum queue length specifiable by listen.  */
313 #define SOMAXCONN	4096
314 
315 /* Flags we can use with send/ and recv.
316    Added those for 1003.1g not all are supported yet
317  */
318 
319 #define MSG_OOB		1
320 #define MSG_PEEK	2
321 #define MSG_DONTROUTE	4
322 #define MSG_TRYHARD     4       /* Synonym for MSG_DONTROUTE for DECnet */
323 #define MSG_CTRUNC	8
324 #define MSG_PROBE	0x10	/* Do not send. Only probe path f.e. for MTU */
325 #define MSG_TRUNC	0x20
326 #define MSG_DONTWAIT	0x40	/* Nonblocking io		 */
327 #define MSG_EOR         0x80	/* End of record */
328 #define MSG_WAITALL	0x100	/* Wait for a full request */
329 #define MSG_FIN         0x200
330 #define MSG_SYN		0x400
331 #define MSG_CONFIRM	0x800	/* Confirm path validity */
332 #define MSG_RST		0x1000
333 #define MSG_ERRQUEUE	0x2000	/* Fetch message from error queue */
334 #define MSG_NOSIGNAL	0x4000	/* Do not generate SIGPIPE */
335 #define MSG_MORE	0x8000	/* Sender will send more */
336 #define MSG_WAITFORONE	0x10000	/* recvmmsg(): block until 1+ packets avail */
337 #define MSG_SENDPAGE_NOPOLICY 0x10000 /* sendpage() internal : do no apply policy */
338 #define MSG_BATCH	0x40000 /* sendmmsg(): more messages coming */
339 #define MSG_EOF         MSG_FIN
340 #define MSG_NO_SHARED_FRAGS 0x80000 /* sendpage() internal : page frags are not shared */
341 #define MSG_SENDPAGE_DECRYPTED	0x100000 /* sendpage() internal : page may carry
342 					  * plain text and require encryption
343 					  */
344 
345 #define MSG_SOCK_DEVMEM 0x2000000	/* Receive devmem skbs as cmsg */
346 #define MSG_ZEROCOPY	0x4000000	/* Use user data in kernel path */
347 #define MSG_SPLICE_PAGES 0x8000000	/* Splice the pages from the iterator in sendmsg() */
348 #define MSG_FASTOPEN	0x20000000	/* Send data in TCP SYN */
349 #define MSG_CMSG_CLOEXEC 0x40000000	/* Set close_on_exec for file
350 					   descriptor received through
351 					   SCM_RIGHTS */
352 #if defined(CONFIG_COMPAT)
353 #define MSG_CMSG_COMPAT	0x80000000	/* This message needs 32 bit fixups */
354 #else
355 #define MSG_CMSG_COMPAT	0		/* We never have 32 bit fixups */
356 #endif
357 
358 /* Flags to be cleared on entry by sendmsg and sendmmsg syscalls */
359 #define MSG_INTERNAL_SENDMSG_FLAGS \
360 	(MSG_SPLICE_PAGES | MSG_SENDPAGE_NOPOLICY | MSG_SENDPAGE_DECRYPTED)
361 
362 /* Setsockoptions(2) level. Thanks to BSD these must match IPPROTO_xxx */
363 #define SOL_IP		0
364 /* #define SOL_ICMP	1	No-no-no! Due to Linux :-) we cannot use SOL_ICMP=1 */
365 #define SOL_TCP		6
366 #define SOL_UDP		17
367 #define SOL_IPV6	41
368 #define SOL_ICMPV6	58
369 #define SOL_SCTP	132
370 #define SOL_UDPLITE	136     /* UDP-Lite (RFC 3828) */
371 #define SOL_RAW		255
372 #define SOL_IPX		256
373 #define SOL_AX25	257
374 #define SOL_ATALK	258
375 #define SOL_NETROM	259
376 #define SOL_ROSE	260
377 #define SOL_DECNET	261
378 #define	SOL_X25		262
379 #define SOL_PACKET	263
380 #define SOL_ATM		264	/* ATM layer (cell level) */
381 #define SOL_AAL		265	/* ATM Adaption Layer (packet level) */
382 #define SOL_IRDA        266
383 #define SOL_NETBEUI	267
384 #define SOL_LLC		268
385 #define SOL_DCCP	269
386 #define SOL_NETLINK	270
387 #define SOL_TIPC	271
388 #define SOL_RXRPC	272
389 #define SOL_PPPOL2TP	273
390 #define SOL_BLUETOOTH	274
391 #define SOL_PNPIPE	275
392 #define SOL_RDS		276
393 #define SOL_IUCV	277
394 #define SOL_CAIF	278
395 #define SOL_ALG		279
396 #define SOL_NFC		280
397 #define SOL_KCM		281
398 #define SOL_TLS		282
399 #define SOL_XDP		283
400 #define SOL_MPTCP	284
401 #define SOL_MCTP	285
402 #define SOL_SMC		286
403 #define SOL_VSOCK	287
404 
405 /* IPX options */
406 #define IPX_TYPE	1
407 
408 extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr);
409 extern int put_cmsg(struct msghdr*, int level, int type, int len, void *data);
410 extern int put_cmsg_notrunc(struct msghdr *msg, int level, int type, int len,
411 			    void *data);
412 
413 struct timespec64;
414 struct __kernel_timespec;
415 struct old_timespec32;
416 
417 struct scm_timestamping_internal {
418 	struct timespec64 ts[3];
419 };
420 
421 extern void put_cmsg_scm_timestamping64(struct msghdr *msg, struct scm_timestamping_internal *tss);
422 extern void put_cmsg_scm_timestamping(struct msghdr *msg, struct scm_timestamping_internal *tss);
423 
424 /* The __sys_...msg variants allow MSG_CMSG_COMPAT iff
425  * forbid_cmsg_compat==false
426  */
427 extern long __sys_recvmsg(int fd, struct user_msghdr __user *msg,
428 			  unsigned int flags, bool forbid_cmsg_compat);
429 extern long __sys_sendmsg(int fd, struct user_msghdr __user *msg,
430 			  unsigned int flags, bool forbid_cmsg_compat);
431 extern int __sys_recvmmsg(int fd, struct mmsghdr __user *mmsg,
432 			  unsigned int vlen, unsigned int flags,
433 			  struct __kernel_timespec __user *timeout,
434 			  struct old_timespec32 __user *timeout32);
435 extern int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg,
436 			  unsigned int vlen, unsigned int flags,
437 			  bool forbid_cmsg_compat);
438 extern long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
439 			       unsigned int flags);
440 extern long __sys_recvmsg_sock(struct socket *sock, struct msghdr *msg,
441 			       struct user_msghdr __user *umsg,
442 			       struct sockaddr __user *uaddr,
443 			       unsigned int flags);
444 extern int __copy_msghdr(struct msghdr *kmsg,
445 			 struct user_msghdr *umsg,
446 			 struct sockaddr __user **save_addr);
447 
448 /* helpers which do the actual work for syscalls */
449 extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size,
450 			  unsigned int flags, struct sockaddr __user *addr,
451 			  int __user *addr_len);
452 extern int __sys_sendto(int fd, void __user *buff, size_t len,
453 			unsigned int flags, struct sockaddr __user *addr,
454 			int addr_len);
455 extern struct file *do_accept(struct file *file, struct proto_accept_arg *arg,
456 			      struct sockaddr __user *upeer_sockaddr,
457 			      int __user *upeer_addrlen, int flags);
458 extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
459 			 int __user *upeer_addrlen, int flags);
460 extern int __sys_socket(int family, int type, int protocol);
461 extern struct file *__sys_socket_file(int family, int type, int protocol);
462 extern int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen);
463 extern int __sys_bind_socket(struct socket *sock, struct sockaddr_storage *address,
464 			     int addrlen);
465 extern int __sys_connect_file(struct file *file, struct sockaddr_storage *addr,
466 			      int addrlen, int file_flags);
467 extern int __sys_connect(int fd, struct sockaddr __user *uservaddr,
468 			 int addrlen);
469 extern int __sys_listen(int fd, int backlog);
470 extern int __sys_listen_socket(struct socket *sock, int backlog);
471 extern int do_getsockname(struct socket *sock, int peer,
472 			  struct sockaddr __user *usockaddr, int __user *usockaddr_len);
473 extern int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
474 			     int __user *usockaddr_len, int peer);
475 extern int __sys_socketpair(int family, int type, int protocol,
476 			    int __user *usockvec);
477 extern int __sys_shutdown_sock(struct socket *sock, int how);
478 extern int __sys_shutdown(int fd, int how);
479 #endif /* _LINUX_SOCKET_H */
480