AF_INET datagram sockets: UDP (SOCK_DGRAM), and ping sockets (SOCK_DGRAM with IPPROTO_ICMP), which send echo requests and receive the replies, without needing root. More...

#include <core/system.h>
#include <dev/random.h>
#include <core/string.h>
#include <core/arch.h>
#include <ds/queue.h>
#include <fs/vfs.h>
#include <net/byteorder.h>
#include <net/inet.h>
#include <net/socket.h>
#include <sys/proc.h>
#include <sys/sched.h>
#include <sys/uaccess.h>
#include <aquila/errno.h>
#include <aquila/fcntl.h>
#include <aquila/in.h>
#include <aquila/ioctl.h>

Data Structures
struct	inet_sock
	A UDP or ping socket. More...

Macros
#define	RECV_MAX (128 * NETBUF_SIZE)
#define	PORT_FIRST 49152
#define	PORT_LAST 65535

Functions
static int	port_used (uint8_t proto, uint32_t addr, uint16_t port)
	Returns whether a socket of proto is bound to port on addr (or on any address, or addr is any).
static int	sock_bind (struct inet_sock *sock, uint32_t addr, uint16_t port)
	Binds a socket to an address and port, and puts it on the list of bound sockets.
static void	sock_unbind (struct inet_sock *sock)
	Takes a socket off the list of bound sockets.
struct inet_sock *	inet_sock_find (struct netif *netif, uint8_t proto, uint32_t local, uint16_t port, uint32_t remote, uint16_t remote_port)
	Finds the socket that a received datagram is for: a socket connected to its sender first, or else one that isn't connected.
void	inet_sock_deliver (struct inet_sock sock, struct netbuf nb)
	Queues a received datagram on its socket, and wakes up its readers.
void	inet_sock_error (struct inet_sock *sock, int err)
	Gives a socket an error (from ICMP), which its next call reports.
int	socket_inet_create (struct file *file, int domain, int type, int protocol)
	Makes an AF_INET socket: a TCP, UDP or ping socket.
int	inet_sockaddr_get (const struct sockaddr addr, socklen_t len, uint32_t ip, uint16_t *port)
	Reads an AF_INET address.
void	inet_sockaddr_put (struct sockaddr addr, socklen_t len, uint32_t ip, uint16_t port)
	Writes an AF_INET address, cut to *len bytes if it doesn't fit.
static int	socket_inet_bind (struct file file, const struct sockaddr addr, socklen_t len)
	Binds a socket to an address that is ours, any address, or the broadcast address.
static int	socket_inet_connect (struct file file, const struct sockaddr addr, socklen_t len)
	Connects a datagram socket: its default destination, and the only sender it receives from.
static ssize_t	socket_inet_send (struct file file, struct iobuf io, int flags, const struct sockaddr *to, socklen_t tolen)
	Sends a datagram, whole: to to, or to the connected peer.
static ssize_t	socket_inet_recv (struct file file, struct iobuf io, int flags, struct sockaddr from, socklen_t fromlen)
	Receives a datagram, waiting for one unless the socket doesn't block or the receive timeout passes.
static int	socket_inet_can_read (struct file *file, size_t len)
	Says whether a read wouldn't wait: a datagram is queued, or there is an error to report, or reading is shut down.
static int	socket_inet_can_write (struct file *file, size_t len)
	Says that a write never waits.
static struct waitq *	socket_inet_wait_queue (struct file *file, int write)
	Returns the wait queue that the socket's readers sleep on; writers never wait.
static int	socket_inet_getname (struct file file, struct sockaddr addr, socklen_t *len, int peer)
	Gets the socket's local address, or its peer's (-ENOTCONN if it isn't connected).
static int	socket_inet_getsockopt (struct file file, int level, int name, void val, socklen_t *len)
	Reads a socket option: SO_ERROR, SO_BROADCAST, SO_BINDTODEVICE or SO_RCVTIMEO.
static int	socket_inet_setsockopt (struct file file, int level, int name, const void val, socklen_t len)
	Sets a socket option: SO_BROADCAST, SO_BINDTODEVICE or SO_RCVTIMEO.
static int	socket_inet_ioctl (struct file file, int request, void argp)
	Handles FIONREAD (the size of the next datagram) and the interface requests.
static int	socket_inet_shut (struct file *file, int how)
	Shuts down reading: the readers wake up and see the end.
static int	socket_inet_shutdown (struct file *file, int how)
	Frees the socket when its last descriptor is closed: it is unbound, and its queued datagrams are freed.

Variables
static struct inet_sock *	bound
static struct sock_ops	socket_inet_ops

Detailed Description

AF_INET datagram sockets: UDP (SOCK_DGRAM), and ping sockets (SOCK_DGRAM with IPPROTO_ICMP), which send echo requests and receive the replies, without needing root.

TCP sockets are in tcp_socket.c.

A socket bound to a port (for a ping socket, the identifier of its echoes) is on the list of bound sockets, where the protocols look up the socket a datagram is for. Received datagrams wait in the socket's queue, with where they came from, up to RECV_MAX bytes of buffers; more are dropped.

Definition in file socket.c.

Macro Definition Documentation

◆ PORT_FIRST

#define PORT_FIRST 49152

Definition at line 41 of file socket.c.

Referenced by bind_port(), and sock_bind().

◆ PORT_LAST

#define PORT_LAST 65535

Definition at line 42 of file socket.c.

Referenced by bind_port(), and sock_bind().

◆ RECV_MAX

#define RECV_MAX (128 * NETBUF_SIZE)

Definition at line 39 of file socket.c.

Referenced by inet_sock_deliver().

Function Documentation

◆ inet_sock_deliver()

void inet_sock_deliver	(	struct inet_sock *	sock,
		struct netbuf *	nb )

Queues a received datagram on its socket, and wakes up its readers.

The datagram is dropped if the socket's queue is full or reading is shut down. The netbuf is the socket's from now on.

Parameters

sock	the socket
nb	the datagram's data, with src_ip and src_port set

Definition at line 185 of file socket.c.

References inet_sock_deliver(), netbuf_free(), NETBUF_SIZE, netbuf::next, NULL, inet_sock::recv_bytes, inet_sock::recv_head, RECV_MAX, inet_sock::recv_tail, inet_sock::recv_wait, inet_sock::shut_rd, and waitq_wakeup().

Referenced by icmp_input(), inet_sock_deliver(), and udp_input().

◆ inet_sock_error()

void inet_sock_error	(	struct inet_sock *	sock,
		int	err )

Gives a socket an error (from ICMP), which its next call reports.

Parameters

sock	the socket
err	the error (a positive errno)

Definition at line 211 of file socket.c.

References inet_sock::error, inet_sock_error(), inet_sock::recv_wait, and waitq_wakeup().

Referenced by icmp_unreachable_input(), and inet_sock_error().

◆ inet_sock_find()

struct inet_sock * inet_sock_find	(	struct netif *	netif,
		uint8_t	proto,
		uint32_t	local,
		uint16_t	port,
		uint32_t	remote,
		uint16_t	remote_port )

Finds the socket that a received datagram is for: a socket connected to its sender first, or else one that isn't connected.

A socket bound to another interface doesn't count. For ping sockets, the remote port doesn't count.

Parameters

netif	the interface it came in on
proto	IP_PROTO_UDP or IP_PROTO_ICMP
local	the address it was sent to
port	the port it was sent to (a ping's identifier)
remote	the sender's address
remote_port	the sender's port

Returns: the socket, or NULL

Definition at line 154 of file socket.c.

References bound, inet_sock_find(), IP_PROTO_ICMP, inet_sock::next, NULL, and inet_sock::proto.

Referenced by icmp_input(), icmp_unreachable_input(), inet_sock_find(), and udp_input().

◆ inet_sockaddr_get()

int inet_sockaddr_get	(	const struct sockaddr *	addr,
		socklen_t	len,
		uint32_t *	ip,
		uint16_t *	port )

Reads an AF_INET address.

Parameters

addr	the address, in the kernel's memory
len	its size
ip	set to its IPv4 address
port	set to its port

Returns: 0, -EINVAL if it's too short, or -EAFNOSUPPORT

Definition at line 283 of file socket.c.

References inet_sockaddr_get().

Referenced by inet_sockaddr_get(), socket_inet_bind(), socket_inet_connect(), socket_inet_send(), socket_tcp_bind(), and socket_tcp_connect().

◆ inet_sockaddr_put()

void inet_sockaddr_put	(	struct sockaddr *	addr,
		socklen_t *	len,
		uint32_t	ip,
		uint16_t	port )

Writes an AF_INET address, cut to *len bytes if it doesn't fit.

Parameters

addr	where to write it
len	its room, set to the address's full size
ip	the IPv4 address
port	the port

Definition at line 306 of file socket.c.

References inet_sockaddr_put(), memcpy(), and MIN.

Referenced by inet_sockaddr_put(), socket_inet_getname(), socket_inet_recv(), socket_tcp_accept(), socket_tcp_getname(), and socket_tcp_recv().

◆ port_used()

int port_used	(	uint8_t	proto,
		uint32_t	addr,
		uint16_t	port )

static

Returns whether a socket of proto is bound to port on addr (or on any address, or addr is any).

Definition at line 80 of file socket.c.

References bound, inet_sock::next, and port_used().

Referenced by bind_port(), port_used(), port_used(), and sock_bind().

◆ sock_bind()

int sock_bind	(	struct inet_sock *	sock,
		uint32_t	addr,
		uint16_t	port )

static

Binds a socket to an address and port, and puts it on the list of bound sockets.

Port 0 picks a free ephemeral port. Returns 0, or -EADDRINUSE.

Definition at line 93 of file socket.c.

References bound, htons, inet_sock::laddr, inet_sock::lport, inet_sock::next, PORT_FIRST, PORT_LAST, port_used(), inet_sock::proto, random_get(), and sock_bind().

Referenced by sock_bind(), socket_inet_bind(), and socket_inet_connect().

◆ sock_unbind()

void sock_unbind ( struct inet_sock * sock )

static

Takes a socket off the list of bound sockets.

Definition at line 128 of file socket.c.

References bound, inet_sock::lport, inet_sock::next, and sock_unbind().

Referenced by sock_unbind(), and socket_inet_shutdown().

◆ socket_inet_bind()

int socket_inet_bind	(	struct file *	file,
		const struct sockaddr *	addr,
		socklen_t	len )

static

Binds a socket to an address that is ours, any address, or the broadcast address.

Ports below 1024 are root's.

Definition at line 320 of file socket.c.

References curproc, inet_sockaddr_get(), IP_PROTO_UDP, ipv4_is_local(), inet_sock::lport, ntohs, inet_sock::proto, sock_bind(), and socket_inet_bind().

Referenced by socket_inet_bind().

◆ socket_inet_can_read()

int socket_inet_can_read	(	struct file *	file,
		size_t	len )

static

Says whether a read wouldn't wait: a datagram is queued, or there is an error to report, or reading is shut down.

Definition at line 533 of file socket.c.

References inet_sock::error, netbuf::len, inet_sock::recv_head, inet_sock::shut_rd, and socket_inet_can_read().

Referenced by socket_inet_can_read().

◆ socket_inet_can_write()

int socket_inet_can_write	(	struct file *	file,
		size_t	len )

static

Says that a write never waits.

Definition at line 541 of file socket.c.

References socket_inet_can_write().

Referenced by socket_inet_can_write().

◆ socket_inet_connect()

int socket_inet_connect	(	struct file *	file,
		const struct sockaddr *	addr,
		socklen_t	len )

static

Connects a datagram socket: its default destination, and the only sender it receives from.

AF_UNSPEC disconnects it.

Definition at line 347 of file socket.c.

References inet_sock::connected, inet_sock::error, inet_sockaddr_get(), IP_PROTO_UDP, inet_sock::lport, inet_sock::proto, inet_sock::raddr, inet_sock::rport, sock_bind(), and socket_inet_connect().

Referenced by socket_inet_connect().

◆ socket_inet_create()

int socket_inet_create	(	struct file *	file,
		int	domain,
		int	type,
		int	protocol )

Makes an AF_INET socket: a TCP, UDP or ping socket.

Parameters

file	the open file that becomes the socket
domain	AF_INET
type	SOCK_STREAM or SOCK_DGRAM
protocol	0, IPPROTO_TCP, IPPROTO_UDP or IPPROTO_ICMP

Returns: 0, -EPROTONOSUPPORT, or -ENOMEM

Definition at line 230 of file socket.c.

References socket::domain, FILE_SOCKET, file::flags, IP_PROTO_ICMP, IP_PROTO_UDP, kfree(), kmalloc(), M_ZERO, socket::ops, socket::p, inet_sock::proto, socket::protocol, socket_inet_create(), socket_inet_ops, socket_tcp_create(), and socket::type.

Referenced by socket_create(), and socket_inet_create().

◆ socket_inet_getname()

int socket_inet_getname	(	struct file *	file,
		struct sockaddr *	addr,
		socklen_t *	len,
		int	peer )

static

Gets the socket's local address, or its peer's (-ENOTCONN if it isn't connected).

Definition at line 556 of file socket.c.

References inet_sock::connected, inet_sockaddr_put(), inet_sock::laddr, inet_sock::lport, inet_sock::raddr, inet_sock::rport, and socket_inet_getname().

Referenced by socket_inet_getname().

◆ socket_inet_getsockopt()

int socket_inet_getsockopt	(	struct file *	file,
		int	level,
		int	name,
		void *	val,
		socklen_t *	len )

static

Reads a socket option: SO_ERROR, SO_BROADCAST, SO_BINDTODEVICE or SO_RCVTIMEO.

Definition at line 574 of file socket.c.

References inet_sock::broadcast, inet_sock::error, memcpy(), netif::name, inet_sock::netif, inet_sock::rcvtimeo, socket_inet_getsockopt(), timeval::tv_sec, and timeval::tv_usec.

Referenced by socket_inet_getsockopt().

◆ socket_inet_ioctl()

int socket_inet_ioctl	(	struct file *	file,
		int	request,
		void *	argp )

static

Handles FIONREAD (the size of the next datagram) and the interface requests.

Definition at line 686 of file socket.c.

References inet_ifioctl(), netbuf::len, inet_sock::recv_head, and socket_inet_ioctl().

Referenced by socket_inet_ioctl().

◆ socket_inet_recv()

ssize_t socket_inet_recv	(	struct file *	file,
		struct iobuf *	io,
		int	flags,
		struct sockaddr *	from,
		socklen_t *	fromlen )

static

Receives a datagram, waiting for one unless the socket doesn't block or the receive timeout passes.

A datagram longer than the buffer is cut; the rest is lost. Returns its size, 0 once reading is shut down, or a negative errno.

Definition at line 481 of file socket.c.

References arch_rtime_ns(), netbuf::data, inet_sock::error, file::flags, inet_sockaddr_put(), iobuf_out(), netbuf::len, netbuf_free(), NETBUF_SIZE, netbuf::next, NULL, inet_sock::rcvtimeo, inet_sock::recv_bytes, inet_sock::recv_head, inet_sock::recv_tail, inet_sock::recv_wait, sched_wait(), inet_sock::shut_rd, socket_inet_recv(), netbuf::src_ip, and netbuf::src_port.

Referenced by socket_inet_recv().

◆ socket_inet_send()

ssize_t socket_inet_send	(	struct file *	file,
		struct iobuf *	io,
		int	flags,
		const struct sockaddr *	to,
		socklen_t	tolen )

static

Sends a datagram, whole: to to, or to the connected peer.

A ping socket's data must be an echo request; its identifier is the socket's. Returns the datagram's size, or a negative errno.

Definition at line 381 of file socket.c.

References inet_sock::broadcast, icmp_hdr::checksum, udp_hdr::checksum, icmp_hdr::code, inet_sock::connected, udp_hdr::dst, inet_sock::error, netif::flags, htons, ICMP_ECHO_REQUEST, icmp_hdr::id, inet_checksum(), inet_checksum_pseudo(), inet_sockaddr_get(), netif::ip, IP_PROTO_UDP, ipv4_output(), ipv4_route(), ipv4_source(), udp_hdr::len, inet_sock::lport, netbuf_alloc(), netbuf_free(), netbuf_push(), inet_sock::netif, NETIF_UP, netif::netmask, inet_sock::proto, inet_sock::raddr, iobuf::resid, inet_sock::rport, socket_inet_send(), udp_hdr::src, and icmp_hdr::type.

Referenced by socket_inet_send().

◆ socket_inet_setsockopt()

int socket_inet_setsockopt	(	struct file *	file,
		int	level,
		int	name,
		const void *	val,
		socklen_t	len )

static

Sets a socket option: SO_BROADCAST, SO_BINDTODEVICE or SO_RCVTIMEO.

Definition at line 627 of file socket.c.

References inet_sock::broadcast, curproc, memcpy(), MIN, netif::name, inet_sock::netif, netif_find(), NULL, inet_sock::rcvtimeo, socket_inet_setsockopt(), timeval::tv_sec, and timeval::tv_usec.

Referenced by socket_inet_setsockopt().

◆ socket_inet_shut()

int socket_inet_shut	(	struct file *	file,
		int	how )

static

Shuts down reading: the readers wake up and see the end.

Shutting down writing does nothing for a datagram socket.

Definition at line 700 of file socket.c.

References inet_sock::recv_wait, inet_sock::shut_rd, socket_inet_shut(), and waitq_wakeup().

Referenced by socket_inet_shut().

◆ socket_inet_shutdown()

int socket_inet_shutdown	(	struct file *	file,
		int	how )

static

Frees the socket when its last descriptor is closed: it is unbound, and its queued datagrams are freed.

Definition at line 714 of file socket.c.

References kfree(), inet_sock::lport, netbuf_free(), netbuf::next, NULL, inet_sock::recv_head, sock_unbind(), and socket_inet_shutdown().

Referenced by socket_inet_shutdown().

◆ socket_inet_wait_queue()

struct waitq * socket_inet_wait_queue	(	struct file *	file,
		int	write )

static

Returns the wait queue that the socket's readers sleep on; writers never wait.

Definition at line 548 of file socket.c.

References NULL, inet_sock::recv_wait, and socket_inet_wait_queue().

Referenced by socket_inet_wait_queue().

Variable Documentation

◆ bound

struct inet_sock* bound

static

Definition at line 70 of file socket.c.

Referenced by inet_sock_find(), port_used(), sock_bind(), and sock_unbind().

◆ socket_inet_ops

struct sock_ops socket_inet_ops

static

Initial value:

                     = {
    .bind       = socket_inet_bind,
    .connect    = socket_inet_connect,
    .recv       = socket_inet_recv,
    .send       = socket_inet_send,
    .can_read   = socket_inet_can_read,
    .can_write  = socket_inet_can_write,
    .wait_queue = socket_inet_wait_queue,
    .getname    = socket_inet_getname,
    .getsockopt = socket_inet_getsockopt,
    .setsockopt = socket_inet_setsockopt,
    .ioctl      = socket_inet_ioctl,
    .shut       = socket_inet_shut,
    .shutdown   = socket_inet_shutdown,
}

Definition at line 72 of file socket.c.

Referenced by socket_inet_create().

Data Structures

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ PORT_FIRST

◆ PORT_LAST

◆ RECV_MAX

Function Documentation

◆ inet_sock_deliver()

◆ inet_sock_error()

◆ inet_sock_find()

◆ inet_sockaddr_get()

◆ inet_sockaddr_put()

◆ port_used()

◆ sock_bind()

◆ sock_unbind()

◆ socket_inet_bind()

◆ socket_inet_can_read()

◆ socket_inet_can_write()

◆ socket_inet_connect()

◆ socket_inet_create()

◆ socket_inet_getname()

◆ socket_inet_getsockopt()

◆ socket_inet_ioctl()

◆ socket_inet_recv()

◆ socket_inet_send()

◆ socket_inet_setsockopt()

◆ socket_inet_shut()

◆ socket_inet_shutdown()

◆ socket_inet_wait_queue()

Variable Documentation

◆ bound

◆ socket_inet_ops