blob: ba736b457a0683c6358495b738502b9f6b1335fb [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
* NET An implementation of the SOCKET network access protocol.
* This is the master header file for the Linux NET layer,
* or, in plain English: the networking handling part of the
* kernel.
* Version: @(#)net.h 1.0.3 05/25/93
* Authors: Orest Zborowski, <obz@Kodak.COM>
* Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
#ifndef _LINUX_NET_H
#define _LINUX_NET_H
#include <linux/stringify.h>
#include <linux/random.h>
#include <linux/wait.h>
#include <linux/fcntl.h> /* For O_CLOEXEC and O_NONBLOCK */
#include <linux/rcupdate.h>
#include <linux/once.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/sockptr.h>
#include <uapi/linux/net.h>
struct poll_table_struct;
struct pipe_inode_info;
struct inode;
struct file;
struct net;
* in sock->flags, but moved into sk->sk_wq->flags to be RCU protected.
* Eventually all flags will be in sk->sk_wq->flags.
#define SOCK_NOSPACE 2
#define SOCK_PASSSEC 4
* enum sock_type - Socket types
* @SOCK_STREAM: stream (connection) socket
* @SOCK_DGRAM: datagram (conn.less) socket
* @SOCK_RAW: raw socket
* @SOCK_RDM: reliably-delivered message
* @SOCK_SEQPACKET: sequential packet socket
* @SOCK_DCCP: Datagram Congestion Control Protocol socket
* @SOCK_PACKET: linux specific way of getting packets at the dev level.
* For writing rarp and other similar things on the user level.
* When adding some new socket type please
* grep ARCH_HAS_SOCKET_TYPE include/asm-* /socket.h, at least MIPS
* overrides this enum for binary compat reasons.
enum sock_type {
#define SOCK_MAX (SOCK_PACKET + 1)
/* Mask which covers at least up to SOCK_MASK-1. The
* remaining bits are used as flags. */
#define SOCK_TYPE_MASK 0xf
/* Flags for socket, socketpair, accept4 */
* enum sock_shutdown_cmd - Shutdown types
* @SHUT_RD: shutdown receptions
* @SHUT_WR: shutdown transmissions
* @SHUT_RDWR: shutdown receptions/transmissions
enum sock_shutdown_cmd {
struct socket_wq {
/* Note: wait MUST be first field of socket_wq */
wait_queue_head_t wait;
struct fasync_struct *fasync_list;
unsigned long flags; /* %SOCKWQ_ASYNC_NOSPACE, etc */
struct rcu_head rcu;
} ____cacheline_aligned_in_smp;
* struct socket - general BSD socket
* @state: socket state (%SS_CONNECTED, etc)
* @type: socket type (%SOCK_STREAM, etc)
* @flags: socket flags (%SOCK_NOSPACE, etc)
* @ops: protocol specific socket operations
* @file: File back pointer for gc
* @sk: internal networking protocol agnostic socket representation
* @wq: wait queue for several uses
struct socket {
socket_state state;
short type;
unsigned long flags;
struct file *file;
struct sock *sk;
const struct proto_ops *ops;
struct socket_wq wq;
struct vm_area_struct;
struct page;
struct sockaddr;
struct msghdr;
struct module;
struct sk_buff;
typedef int (*sk_read_actor_t)(read_descriptor_t *, struct sk_buff *,
unsigned int, size_t);
struct proto_ops {
int family;
struct module *owner;
int (*release) (struct socket *sock);
int (*bind) (struct socket *sock,
struct sockaddr *myaddr,
int sockaddr_len);
int (*connect) (struct socket *sock,
struct sockaddr *vaddr,
int sockaddr_len, int flags);
int (*socketpair)(struct socket *sock1,
struct socket *sock2);
int (*accept) (struct socket *sock,
struct socket *newsock, int flags, bool kern);
int (*getname) (struct socket *sock,
struct sockaddr *addr,
int peer);
__poll_t (*poll) (struct file *file, struct socket *sock,
struct poll_table_struct *wait);
int (*ioctl) (struct socket *sock, unsigned int cmd,
unsigned long arg);
int (*compat_ioctl) (struct socket *sock, unsigned int cmd,
unsigned long arg);
int (*gettstamp) (struct socket *sock, void __user *userstamp,
bool timeval, bool time32);
int (*listen) (struct socket *sock, int len);
int (*shutdown) (struct socket *sock, int flags);
int (*setsockopt)(struct socket *sock, int level,
int optname, sockptr_t optval,
unsigned int optlen);
int (*getsockopt)(struct socket *sock, int level,
int optname, char __user *optval, int __user *optlen);
void (*show_fdinfo)(struct seq_file *m, struct socket *sock);
int (*sendmsg) (struct socket *sock, struct msghdr *m,
size_t total_len);
/* Notes for implementing recvmsg:
* ===============================
* msg->msg_namelen should get updated by the recvmsg handlers
* iff msg_name != NULL. It is by default 0 to prevent
* returning uninitialized memory to user space. The recvfrom
* handlers can assume that msg.msg_name is either NULL or has
* a minimum size of sizeof(struct sockaddr_storage).
int (*recvmsg) (struct socket *sock, struct msghdr *m,
size_t total_len, int flags);
int (*mmap) (struct file *file, struct socket *sock,
struct vm_area_struct * vma);
ssize_t (*sendpage) (struct socket *sock, struct page *page,
int offset, size_t size, int flags);
ssize_t (*splice_read)(struct socket *sock, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len, unsigned int flags);
int (*set_peek_off)(struct sock *sk, int val);
int (*peek_len)(struct socket *sock);
/* The following functions are called internally by kernel with
* sock lock already held.
int (*read_sock)(struct sock *sk, read_descriptor_t *desc,
sk_read_actor_t recv_actor);
int (*sendpage_locked)(struct sock *sk, struct page *page,
int offset, size_t size, int flags);
int (*sendmsg_locked)(struct sock *sk, struct msghdr *msg,
size_t size);
int (*set_rcvlowat)(struct sock *sk, int val);
#define DECLARE_SOCKADDR(type, dst, src) \
type dst = ({ __sockaddr_check_size(sizeof(*dst)); (type) src; })
struct net_proto_family {
int family;
int (*create)(struct net *net, struct socket *sock,
int protocol, int kern);
struct module *owner;
struct iovec;
struct kvec;
enum {
int sock_wake_async(struct socket_wq *sk_wq, int how, int band);
int sock_register(const struct net_proto_family *fam);
void sock_unregister(int family);
bool sock_is_registered(int family);
int __sock_create(struct net *net, int family, int type, int proto,
struct socket **res, int kern);
int sock_create(int family, int type, int proto, struct socket **res);
int sock_create_kern(struct net *net, int family, int type, int proto, struct socket **res);
int sock_create_lite(int family, int type, int proto, struct socket **res);
struct socket *sock_alloc(void);
void sock_release(struct socket *sock);
int sock_sendmsg(struct socket *sock, struct msghdr *msg);
int sock_recvmsg(struct socket *sock, struct msghdr *msg, int flags);
struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname);
struct socket *sockfd_lookup(int fd, int *err);
struct socket *sock_from_file(struct file *file);
#define sockfd_put(sock) fput(sock->file)
int net_ratelimit(void);
#define net_ratelimited_function(function, ...) \
do { \
if (net_ratelimit()) \
function(__VA_ARGS__); \
} while (0)
#define net_emerg_ratelimited(fmt, ...) \
net_ratelimited_function(pr_emerg, fmt, ##__VA_ARGS__)
#define net_alert_ratelimited(fmt, ...) \
net_ratelimited_function(pr_alert, fmt, ##__VA_ARGS__)
#define net_crit_ratelimited(fmt, ...) \
net_ratelimited_function(pr_crit, fmt, ##__VA_ARGS__)
#define net_err_ratelimited(fmt, ...) \
net_ratelimited_function(pr_err, fmt, ##__VA_ARGS__)
#define net_notice_ratelimited(fmt, ...) \
net_ratelimited_function(pr_notice, fmt, ##__VA_ARGS__)
#define net_warn_ratelimited(fmt, ...) \
net_ratelimited_function(pr_warn, fmt, ##__VA_ARGS__)
#define net_info_ratelimited(fmt, ...) \
net_ratelimited_function(pr_info, fmt, ##__VA_ARGS__)
#if defined(CONFIG_DYNAMIC_DEBUG) || \
#define net_dbg_ratelimited(fmt, ...) \
do { \
if (DYNAMIC_DEBUG_BRANCH(descriptor) && \
net_ratelimit()) \
__dynamic_pr_debug(&descriptor, pr_fmt(fmt), \
##__VA_ARGS__); \
} while (0)
#elif defined(DEBUG)
#define net_dbg_ratelimited(fmt, ...) \
net_ratelimited_function(pr_debug, fmt, ##__VA_ARGS__)
#define net_dbg_ratelimited(fmt, ...) \
do { \
if (0) \
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); \
} while (0)
#define net_get_random_once(buf, nbytes) \
get_random_once((buf), (nbytes))
#define net_get_random_once_wait(buf, nbytes) \
get_random_once_wait((buf), (nbytes))
* E.g. XFS meta- & log-data is in slab pages, or bcache meta
* data pages, or other high order pages allocated by
* __get_free_pages() without __GFP_COMP, which have a page_count
* of 0 and/or have PageSlab() set. We cannot use send_page for
* those, as that does get_page(); put_page(); and would cause
* either a VM_BUG directly, or __page_cache_release a page that
* would actually still be referenced by someone, leading to some
* obscure delayed Oops somewhere else.
static inline bool sendpage_ok(struct page *page)
return !PageSlab(page) && page_count(page) >= 1;
int kernel_sendmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
size_t num, size_t len);
int kernel_sendmsg_locked(struct sock *sk, struct msghdr *msg,
struct kvec *vec, size_t num, size_t len);
int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec,
size_t num, size_t len, int flags);
int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen);
int kernel_listen(struct socket *sock, int backlog);
int kernel_accept(struct socket *sock, struct socket **newsock, int flags);
int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
int flags);
int kernel_getsockname(struct socket *sock, struct sockaddr *addr);
int kernel_getpeername(struct socket *sock, struct sockaddr *addr);
int kernel_sendpage(struct socket *sock, struct page *page, int offset,
size_t size, int flags);
int kernel_sendpage_locked(struct sock *sk, struct page *page, int offset,
size_t size, int flags);
int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how);
/* Routine returns the IP overhead imposed by a (caller-protected) socket. */
u32 kernel_sock_ip_overhead(struct sock *sk);
#define MODULE_ALIAS_NETPROTO(proto) \
MODULE_ALIAS("net-pf-" __stringify(proto))
#define MODULE_ALIAS_NET_PF_PROTO(pf, proto) \
MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto))
#define MODULE_ALIAS_NET_PF_PROTO_TYPE(pf, proto, type) \
MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
"-type-" __stringify(type))
#define MODULE_ALIAS_NET_PF_PROTO_NAME(pf, proto, name) \
MODULE_ALIAS("net-pf-" __stringify(pf) "-proto-" __stringify(proto) \
#endif /* _LINUX_NET_H */