Network related helper APIs

Data Structures
struct	lws_dns_score
struct	lws_route

Macros
#define	LWS_ITOSA_USABLE   0
#define	LWS_ITOSA_NOT_EXIST   -1
#define	LWS_ITOSA_NOT_USABLE   -2
#define	LWS_ITOSA_BUSY

Typedefs
typedef uint16_t	lws_route_uidx_t
typedef struct lws_dns_score	lws_dns_score_t
typedef struct lws_route	lws_route_t
typedef lws_route_t	lws_dns_sort_t

Functions
LWS_VISIBLE LWS_EXTERN const char *LWS_WARN_UNUSED_RESULT	lws_canonical_hostname (struct lws_context *context)
LWS_VISIBLE LWS_EXTERN void	lws_get_peer_addresses (struct lws *wsi, lws_sockfd_type fd, char *name, int name_len, char *rip, int rip_len)
LWS_VISIBLE LWS_EXTERN const char *	lws_get_peer_simple (struct lws *wsi, char *name, size_t namelen)
LWS_VISIBLE LWS_EXTERN const char *	lws_get_peer_simple_fd (lws_sockfd_type fd, char *name, size_t namelen)
LWS_VISIBLE LWS_EXTERN int	lws_interface_to_sa (int ipv6, const char *ifname, struct sockaddr_in *addr, size_t addrlen)
LWS_VISIBLE LWS_EXTERN int	lws_sa46_compare_ads (const lws_sockaddr46 *sa46a, const lws_sockaddr46 *sa46b)
LWS_VISIBLE LWS_EXTERN int	lws_sa46_on_net (const lws_sockaddr46 *sa46a, const lws_sockaddr46 *sa46_net, int net_len)
LWS_VISIBLE LWS_EXTERN int	lws_parse_numeric_address (const char *ads, uint8_t *result, size_t max_len)
LWS_VISIBLE LWS_EXTERN int	lws_sa46_parse_numeric_address (const char *ads, lws_sockaddr46 *sa46)
LWS_VISIBLE LWS_EXTERN int	lws_write_numeric_address (const uint8_t *ads, int size, char *buf, size_t len)
LWS_VISIBLE LWS_EXTERN int	lws_sa46_write_numeric_address (lws_sockaddr46 *sa46, char *buf, size_t len)

Detailed Description

Network related helper APIs

These wrap miscellaneous useful network-related functions

Macro Definition Documentation

LWS_ITOSA_BUSY

#define LWS_ITOSA_BUSY

#include <include/libwebsockets/lws-network-helper.h>

Value:

                                        -3 /* only returned by lws_socket_bind() on
                                        EADDRINUSE */

Function Documentation

lws_canonical_hostname()

LWS_VISIBLE LWS_EXTERN const char* LWS_WARN_UNUSED_RESULT lws_canonical_hostname

(

struct lws_context *

context

)

#include <include/libwebsockets/lws-network-helper.h>

lws_canonical_hostname() - returns this host's hostname

This is typically used by client code to fill in the host parameter when making a client connection. You can only call it after the context has been created.

Parameters

context

Websocket context

lws_get_peer_addresses()

LWS_VISIBLE LWS_EXTERN void lws_get_peer_addresses	(	struct lws *	wsi,
		lws_sockfd_type	fd,
		char *	name,
		int	name_len,
		char *	rip,
		int	rip_len
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_get_peer_addresses() - Get client address information

Parameters

wsi	Local struct lws associated with
fd	Connection socket descriptor
name	Buffer to take client address name
name_len	Length of client address name buffer
rip	Buffer to take client address IP dotted quad
rip_len	Length of client address IP buffer This function fills in name and rip with the name and IP of the client connected with socket descriptor fd. Names may be truncated if there is not enough room. If either cannot be determined, they will be returned as valid zero-length strings.

lws_get_peer_simple()

LWS_VISIBLE LWS_EXTERN const char* lws_get_peer_simple	(	struct lws *	wsi,
		char *	name,
		size_t	namelen
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_get_peer_simple() - Get client address information without RDNS

Parameters

wsi	Local struct lws associated with
name	Buffer to take client address name
namelen	Length of client address name buffer

This provides a 123.123.123.123 type IP address in name from the peer that has connected to wsi

lws_interface_to_sa()

LWS_VISIBLE LWS_EXTERN int lws_interface_to_sa	(	int	ipv6,
		const char *	ifname,
		struct sockaddr_in *	addr,
		size_t	addrlen
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_interface_to_sa() - Convert interface name or IP to sockaddr struct

Parameters

ipv6	Allow IPV6 addresses
ifname	Interface name or IP
addr	struct sockaddr_in * to be written
addrlen	Length of addr

This converts a textual network interface name to a sockaddr usable by other network functions.

If the network interface doesn't exist, it will return LWS_ITOSA_NOT_EXIST.

If the network interface is not usable, eg ethernet cable is removed, it may logically exist but not have any IP address. As such it will return LWS_ITOSA_NOT_USABLE.

If the network interface exists and is usable, it will return LWS_ITOSA_USABLE.

lws_sa46_compare_ads()

LWS_VISIBLE LWS_EXTERN int lws_sa46_compare_ads	(	const lws_sockaddr46 *	sa46a,
		const lws_sockaddr46 *	sa46b
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_sa46_compare_ads() - checks if two sa46 have the same address

Parameters

sa46a	first
sa46b	second

Returns 0 if the address family is INET or INET6 and the address is the same, or if the AF is the same but not INET or INET6, otherwise nonzero.

lws_sa46_on_net()

LWS_VISIBLE LWS_EXTERN int lws_sa46_on_net	(	const lws_sockaddr46 *	sa46a,
		const lws_sockaddr46 *	sa46_net,
		int	net_len
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_sa46_on_net() - checks if an sa46 is on the subnet represented by another

Parameters

sa46a	first
sa46_net	network
net_len	length of network non-mask

Returns 0 if sa46a belongs on network sa46_net/net_len

If there is an ipv4 / v6 mismatch between the ip and the net, the ipv4 address is promoted to ::ffff:x.x.x.x before the comparison.

lws_sa46_write_numeric_address()

LWS_VISIBLE LWS_EXTERN int lws_sa46_write_numeric_address	(	lws_sockaddr46 *	sa46,
		char *	buf,
		size_t	len
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_sa46_write_numeric_address() - convert sa46 ads to textual numeric ads

Parameters

sa46	the sa46 whose address to show
buf	result buffer to take text format
len	max size of text buffer

Converts the ipv4 or ipv6 address in an lws_sockaddr46 to a textual representation of the numeric address, like "1.2.3.4" or "::1". Returns the number of chars written into buf, else < 0. ipv6 only supported with LWS_IPV6=1 at cmake.

lws_write_numeric_address()

LWS_VISIBLE LWS_EXTERN int lws_write_numeric_address	(	const uint8_t *	ads,
		int	size,
		char *	buf,
		size_t	len
	)

#include <include/libwebsockets/lws-network-helper.h>

lws_write_numeric_address() - convert network byte order ads to text

Parameters

ads	network byte order address array
size	number of bytes valid in ads
buf	result buffer to take text format
len	max size of text buffer

Converts an array of network-ordered byte address elements to a textual representation of the numeric address, like "1.2.3.4" or "::1". Returns the number of chars written into buf, else < 0. ipv6 only supported with LWS_IPV6=1 at cmake.