3  * NET		An implementation of the SOCKET network access protocol.
5  * Version:	@(#)socket.c	1.1.93	18/02/95
31  *		Linus		:	Argh. removed all the socket allocation
49  *	This module is effectively the top level interface to the BSD socket
56 #include <linux/socket.h>
135 	struct socket *sock = f->private_data;  in sock_show_fdinfo()
145 …*	Socket files have a set of 'special' operations as well as the generic file ones. These don't ap…
177  * Move socket addresses back and forth across the kernel/user
182  *	move_addr_to_kernel	-	copy a socket address into kernel space
256 	init_waitqueue_head(&ei->socket.wq.wait);  in sock_alloc_inode()
257 	ei->socket.wq.fasync_list = NULL;  in sock_alloc_inode()
258 	ei->socket.wq.flags = 0;  in sock_alloc_inode()
260 	ei->socket.state = SS_UNCONNECTED;  in sock_alloc_inode()
261 	ei->socket.flags = 0;  in sock_alloc_inode()
262 	ei->socket.ops = NULL;  in sock_alloc_inode()
263 	ei->socket.sk = NULL;  in sock_alloc_inode()
264 	ei->socket.file = NULL;  in sock_alloc_inode()
307 	return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",  in sockfs_dname()
383  *	to socket after mapping. If one day we will need it, this
393  *	sock_alloc_file - Bind a &socket to a &file
394  *	@sock: socket
404 struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)  in sock_alloc_file()
426 static int sock_map_fd(struct socket *sock, int flags)  in sock_map_fd()
446  *	sock_from_file - Return the &socket bounded to @file.
453 struct socket *sock_from_file(struct file *file, int *err)  in sock_from_file()
464  *	sockfd_lookup - Go from a file number to its socket slot
468  *	The file handle passed in is locked and the socket it is bound
471  *	for both invalid handles and passing a handle which is not a socket.
473  *	On a success the socket object pointer is returned.
476 struct socket *sockfd_lookup(int fd, int *err)  in sockfd_lookup()
479 	struct socket *sock;  in sockfd_lookup()
494 static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)  in sockfd_lookup_light()
497 	struct socket *sock;  in sockfd_lookup_light()
544 		struct socket *sock = SOCKET_I(d_inode(dentry));  in sockfs_setattr()
561  *	sock_alloc - allocate a socket
563  *	Allocate a new inode and socket object. The two are bound together
564  *	and initialised. The socket is then returned. If we are out of inodes
568 struct socket *sock_alloc(void)  in sock_alloc()
571 	struct socket *sock;  in sock_alloc()
589 static void __sock_release(struct socket *sock, struct inode *inode)  in __sock_release()
615  *	sock_release - close a socket
616  *	@sock: socket to close
618  *	The socket is released from the protocol stack if it has a release
619  *	callback, and the inode is then released if the socket is bound to
622 void sock_release(struct socket *sock)  in sock_release()
645 INDIRECT_CALLABLE_DECLARE(int inet_sendmsg(struct socket *, struct msghdr *,
647 INDIRECT_CALLABLE_DECLARE(int inet6_sendmsg(struct socket *, struct msghdr *,
649 static inline int sock_sendmsg_nosec(struct socket *sock, struct msghdr *msg)  in sock_sendmsg_nosec()
660  *	@sock: socket
666 int sock_sendmsg(struct socket *sock, struct msghdr *msg)  in sock_sendmsg()
677  *	@sock: socket
687 int kernel_sendmsg(struct socket *sock, struct msghdr *msg,  in kernel_sendmsg()
711 	struct socket *sock = sk->sk_socket;  in kernel_sendmsg_locked()
726 	 * in recvmsg, since skbs received on a local socket will never  in skb_is_err_queue()
737  * option SO_TIMESTAMP_OLD(NS) is enabled on the socket, even when the skb has a
878 INDIRECT_CALLABLE_DECLARE(int inet_recvmsg(struct socket *, struct msghdr *,
880 INDIRECT_CALLABLE_DECLARE(int inet6_recvmsg(struct socket *, struct msghdr *,
882 static inline int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg,  in sock_recvmsg_nosec()
892  *	@sock: socket
899 int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags)  in sock_recvmsg()
908  *	kernel_recvmsg - Receive a message from a socket (kernel space)
909  *	@sock: The socket to receive the message from
923 int kernel_recvmsg(struct socket *sock, struct msghdr *msg,  in kernel_recvmsg()
935 	struct socket *sock;  in sock_sendpage()
951 	struct socket *sock = file->private_data;  in sock_splice_read()
962 	struct socket *sock = file->private_data;  in sock_read_iter()
984 	struct socket *sock = file->private_data;  in sock_write_iter()
1041 static long sock_do_ioctl(struct net *net, struct socket *sock,  in sock_do_ioctl()
1087 	struct socket *sock;  in sock_ioctl()
1194  *	sock_create_lite - creates a socket
1198  *	@res: new socket
1200  *	Creates a new socket and assigns it to @res, passing through LSM.
1201  *	The new socket initialization is not complete, see kernel_accept().
1206 int sock_create_lite(int family, int type, int protocol, struct socket **res)  in sock_create_lite()
1209 	struct socket *sock = NULL;  in sock_create_lite()
1239 	struct socket *sock = file->private_data;  in sock_poll()
1250 		/* if this socket can poll_ll, tell the system call */  in sock_poll()
1259 	struct socket *sock = file->private_data;  in sock_mmap()
1271  *	Update the socket async list
1275  *	1. fasync_list is modified only under process context socket lock
1278  *	   or under socket lock
1283 	struct socket *sock = filp->private_data;  in sock_fasync()
1331  *	__sock_create - creates a socket
1336  *	@res: new socket
1339  *	Creates a new socket and assigns it to @res, passing through LSM.
1341  *	be set to true if the socket resides in kernel space.
1346 			 struct socket **res, int kern)  in __sock_create()
1349 	struct socket *sock;  in __sock_create()
1376 	 *	Allocate the socket and allow the family to set things up. if  in __sock_create()
1382 		net_warn_ratelimited("socket: no more sockets\n");  in __sock_create()
1422 	 * socket at sock_release time we decrement its refcnt.  in __sock_create()
1455  *	sock_create - creates a socket
1459  *	@res: new socket
1465 int sock_create(int family, int type, int protocol, struct socket **res)  in sock_create()
1472  *	sock_create_kern - creates a socket (kernel space)
1477  *	@res: new socket
1483 int sock_create_kern(struct net *net, int family, int type, int protocol, struct socket **res)  in sock_create_kern()
1492 	struct socket *sock;  in __sys_socket()
1516 SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)  in SYSCALL_DEFINE3()  argument
1527 	struct socket *sock1, *sock2;  in __sys_socketpair()
1563 	 * Obtain the first socket and check if the underlying protocol  in __sys_socketpair()
1624  *	Bind a name to a socket. Nothing much to do here since it's
1627  *	We move the socket address to kernel space before we call
1633 	struct socket *sock;  in __sys_bind()
1661  *	necessary for a listen, and if that works, we mark the socket as
1667 	struct socket *sock;  in __sys_listen()
1696 	struct socket *sock, *newsock;  in __sys_accept4_file()
1720 	 * We don't need try_module_get here, as the listening socket (sock)  in __sys_accept4_file()
1774  *	For accept, we attempt to create a new socket, set up the link
1778  *	we open the socket then return an error.
1815  *	Attempt to connect to a socket with the server address.  The address
1829 	struct socket *sock;  in __sys_connect_file()
1872  *	Get the local address ('name') of a socket object. Move the obtained
1879 	struct socket *sock;  in __sys_getsockname()
1910  *	Get the remote address ('name') of a socket object. Move the obtained
1917 	struct socket *sock;  in __sys_getpeername()
1953 	struct socket *sock;  in __sys_sendto()
1997  *	Send a datagram down a socket.
2007  *	Receive a frame from the socket and optionally record the address of the
2014 	struct socket *sock;  in __sys_recvfrom()
2060  *	Receive a datagram from a socket.
2069 static bool sock_use_custom_sol_socket(const struct socket *sock)  in sock_use_custom_sol_socket()
2081  *	Set a socket option. Because we don't know the option lengths we have
2090 	struct socket *sock;  in __sys_setsockopt()
2136  *	Get a socket option. Because we don't know the option lengths we have
2143 	struct socket *sock;  in __sys_getsockopt()
2181  *	Shutdown a socket.
2187 	struct socket *sock;  in __sys_shutdown()
2286 static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys,  in ____sys_sendmsg()
2381 static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg,  in ___sys_sendmsg()
2405 long __sys_sendmsg_sock(struct socket *sock, struct msghdr *msg,  in __sys_sendmsg_sock()
2420 	struct socket *sock;  in __sys_sendmsg()
2449 	struct socket *sock;  in __sys_sendmmsg()
2539 static int ____sys_recvmsg(struct socket *sock, struct msghdr *msg_sys,  in ____sys_recvmsg()
2595 static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg,  in ___sys_recvmsg()
2616 long __sys_recvmsg_sock(struct socket *sock, struct msghdr *msg,  in __sys_recvmsg_sock()
2634 	struct socket *sock;  in __sys_recvmsg()
2665 	struct socket *sock;  in do_recvmmsg()
2966  *	sock_register - add a socket protocol handler
2971  *	socket interface. The value ops->family corresponds to the
2972  *	socket system call protocol family.
3004  *	new socket creation.
3158 static int compat_ifreq_ioctl(struct net *net, struct socket *sock,  in compat_ifreq_ioctl()
3255 static int compat_sock_ioctl_trans(struct file *file, struct socket *sock,  in compat_sock_ioctl_trans()
3360 	struct socket *sock = file->private_data;  in compat_sock_ioctl()
3383  *	kernel_bind - bind an address to a socket (kernel space)
3384  *	@sock: socket
3391 int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)  in kernel_bind()
3398  *	kernel_listen - move socket to listening state (kernel space)
3399  *	@sock: socket
3405 int kernel_listen(struct socket *sock, int backlog)  in kernel_listen()
3413  *	@sock: listening socket
3414  *	@newsock: new connected socket
3422 int kernel_accept(struct socket *sock, struct socket **newsock, int flags)  in kernel_accept()
3448  *	kernel_connect - connect a socket (kernel space)
3449  *	@sock: socket
3460 int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,  in kernel_connect()
3468  *	kernel_getsockname - get the address which the socket is bound (kernel space)
3469  *	@sock: socket
3472  * 	Fills the @addr pointer with the address which the socket is bound.
3476 int kernel_getsockname(struct socket *sock, struct sockaddr *addr)  in kernel_getsockname()
3483  *	kernel_getpeername - get the address which the socket is connected (kernel space)
3484  *	@sock: socket
3487  * 	Fills the @addr pointer with the address which the socket is connected.
3491 int kernel_getpeername(struct socket *sock, struct sockaddr *addr)  in kernel_getpeername()
3498  *	kernel_sendpage - send a &page through a socket (kernel space)
3499  *	@sock: socket
3508 int kernel_sendpage(struct socket *sock, struct page *page, int offset,  in kernel_sendpage()
3535 	struct socket *sock = sk->sk_socket;  in kernel_sendpage_locked()
3547  *	@sock: socket
3553 int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)  in kernel_sock_shutdown()
3560  *	kernel_sock_ip_overhead - returns the IP overhead imposed by a socket
3561  *	@sk: socket
3563  *	This routine returns the IP overhead imposed by a socket i.e.
3565  *	this is an IPv4 or IPv6 socket and the length from IP options turned
3566  *	on at the socket. Assumes that the caller has a lock on the socket.
3602 	default: /* Returns 0 overhead if the socket is not ipv4 or ipv6 */  in kernel_sock_ip_overhead()