socket.h

  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
 13struct file;
 14struct pid;
 15struct cred;
 16struct socket;
 17struct sock;
 18struct sk_buff;
 19struct 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
 25struct seq_file;
 26extern void socket_seq_show(struct seq_file *seq);
 27#endif
 28
 29typedef __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. */
 36struct 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 */
 53struct sockaddr_unsized {
 54	__kernel_sa_family_t	sa_family;	/* address family, AF_xxx */
 55	char			sa_data[];	/* flexible address data */
 56};
 57
 58struct 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
 71struct 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
 98struct 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 */
109struct 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
120struct 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
169static 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
181static 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
186static 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
198struct 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
408extern int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr);
409extern int put_cmsg(struct msghdr*, int level, int type, int len, void *data);
410extern int put_cmsg_notrunc(struct msghdr *msg, int level, int type, int len,
411			    void *data);
412
413struct timespec64;
414struct __kernel_timespec;
415struct old_timespec32;
416
417struct scm_timestamping_internal {
418	struct timespec64 ts[3];
419};
420
421extern void put_cmsg_scm_timestamping64(struct msghdr *msg, struct scm_timestamping_internal *tss);
422extern 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 */
427extern long __sys_recvmsg(int fd, struct user_msghdr __user *msg,
428			  unsigned int flags, bool forbid_cmsg_compat);
429extern long __sys_sendmsg(int fd, struct user_msghdr __user *msg,
430			  unsigned int flags, bool forbid_cmsg_compat);
431extern 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);
435extern int __sys_sendmmsg(int fd, struct mmsghdr __user *mmsg,
436			  unsigned int vlen, unsigned int flags,
437			  bool forbid_cmsg_compat);
438extern long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,
439			       unsigned int flags);
440extern 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);
444extern 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 */
449extern int __sys_recvfrom(int fd, void __user *ubuf, size_t size,
450			  unsigned int flags, struct sockaddr __user *addr,
451			  int __user *addr_len);
452extern int __sys_sendto(int fd, void __user *buff, size_t len,
453			unsigned int flags, struct sockaddr __user *addr,
454			int addr_len);
455extern 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);
458extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr,
459			 int __user *upeer_addrlen, int flags);
460extern int __sys_socket(int family, int type, int protocol);
461extern struct file *__sys_socket_file(int family, int type, int protocol);
462extern int __sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen);
463extern int __sys_bind_socket(struct socket *sock, struct sockaddr_storage *address,
464			     int addrlen);
465extern int __sys_connect_file(struct file *file, struct sockaddr_storage *addr,
466			      int addrlen, int file_flags);
467extern int __sys_connect(int fd, struct sockaddr __user *uservaddr,
468			 int addrlen);
469extern int __sys_listen(int fd, int backlog);
470extern int __sys_listen_socket(struct socket *sock, int backlog);
471extern int do_getsockname(struct socket *sock, int peer,
472			  struct sockaddr __user *usockaddr, int __user *usockaddr_len);
473extern int __sys_getsockname(int fd, struct sockaddr __user *usockaddr,
474			     int __user *usockaddr_len, int peer);
475extern int __sys_socketpair(int family, int type, int protocol,
476			    int __user *usockvec);
477extern int __sys_shutdown_sock(struct socket *sock, int how);
478extern int __sys_shutdown(int fd, int how);
479#endif /* _LINUX_SOCKET_H */