network_monitor.c File Reference

mptcpd network device monitoring. More...

#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <linux/rtnetlink.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <netinet/in.h>
#include <ell/ell.h>
#include <mptcpd/private/path_manager.h>
#include <mptcpd/private/sockaddr.h>
#include <mptcpd/private/network_monitor.h>
#include <mptcpd/network_monitor.h>

Include dependency graph for network_monitor.c:

Classes
struct	nm_ops_info
	Network monitoring event tracking callback information. More...
struct	mptcpd_nm
	Data needed to run the network monitor. More...
struct	mptcpd_rtm_addr
	Encapsulate network address information. More...
struct	nm_addr_info
	Convenience structure to bundle address information. More...
struct	mptcpd_interface_callback_data
	Callback information supplied by the user. More...

Macros
#define	_POSIX_C_SOURCE   200112L
	For XSI-compliant strerror_r().
#define	_DEFAULT_SOURCE
	For standard network interface flags.
#define	MPTCPD_MAX_ROUTE_CHECK   3

Typedefs
typedef void(*	handle_ifaddr_func_t) (struct mptcpd_nm *nm, struct mptcpd_interface *interface, struct mptcpd_rtm_addr const *rtm_addr)
	Network address handler function signature.

Functions
struct mptcpd_nm *	mptcpd_nm_create (uint32_t flags)
	Create a network monitor.
void	mptcpd_nm_destroy (struct mptcpd_nm *nm)
	Destroy a network monitor.
void	mptcpd_nm_foreach_interface (struct mptcpd_nm const *nm, mptcpd_nm_callback callback, void *callback_data)
	Iterate over all monitored network interfaces.
bool	mptcpd_nm_register_ops (struct mptcpd_nm *nm, struct mptcpd_nm_ops const *ops, void *user_data)
	Subscribe to mptcpd network monitor events.
bool	mptcpd_nm_monitor_loopback (struct mptcpd_nm *nm, bool enable)
	Enable monitoring of the loopback network interface.

Detailed Description

mptcpd network device monitoring.

Copyright (c) 2017-2022, 2024, Intel Corporation

Function Documentation

mptcpd_nm_create()

struct mptcpd_nm * mptcpd_nm_create

(

uint32_t

flags

)

Create a network monitor.

Parameters

[in]

flags

Flags controlling address notification, any of: MPTCPD_NOTIFY_FLAG_EXISTING, MPTCPD_NOTIFY_FLAG_SKIP_LL, MPTCPD_NOTIFY_FLAG_SKIP_HOST

Todo:

As currently implemented, one could create multiple network monitors. Is that useful?

Returns

Pointer to new network monitor on success. NULL on failure.

Get network interface information.

Note

We force the second rtnetlink command, RTM_GETADDR, to be sent after this one completes by doing so in the destroy callback for this command. That guarantees that the potential multipart message response from this dump is fully read prior to sending the second command. This works around an issue in ELL where it was possible that the second command would be sent prior to receiving all of the parts of the multipart RTM_GETLINK response, which resulted in an EBUSY error.

mptcpd_nm_destroy()

void mptcpd_nm_destroy

(

struct mptcpd_nm *

nm

)

Destroy a network monitor.

Parameters

[in,out]

nm

Network monitor to be destroyed.

mptcpd_nm_foreach_interface()

void mptcpd_nm_foreach_interface	(	struct mptcpd_nm const *	nm,
		mptcpd_nm_callback	callback,
		void *	data
	)

Iterate over all monitored network interfaces.

Parameters

[in]	nm	Pointer to the mptcpd network monitor object.
[in]	callback	Function to be called during each network interface iteration.
[in]	data	Data to pass to the callback function during each iteration.

mptcpd_nm_monitor_loopback()

bool mptcpd_nm_monitor_loopback	(	struct mptcpd_nm *	nm,
		bool	enable
	)

Enable monitoring of the loopback network interface.

Mptcpd normally only monitors non-loopback network interfaces. Call this function to enable monitoring of loopback network interfaces.

Note

Mptcpd monitoring of loopback network interfaces is meant primarily for testing purposes.

Parameters

[in,out]	nm	Pointer to the mptcpd network monitor object.
[in]	enable	Enable or disable monitoring of loopback network interfaces.

Return values

true	Successfully enable or disabled.
false	Invalid nm argument.

mptcpd_nm_register_ops()

bool mptcpd_nm_register_ops	(	struct mptcpd_nm *	nm,
		struct mptcpd_nm_ops const *	ops,
		void *	user_data
	)

Subscribe to mptcpd network monitor events.

Register a set of operations that will be called on a corresponding mptcpd network monitoring event, e.g. network interface or address addition, update, or removal.

Parameters

[in,out]	nm	Pointer to the mptcpd network monitor object.
[in]	ops	Set of network monitoring event handling functions.
[in]	user_data	Data to be passed to the network event tracking operations.

Return values

true	Registration succeeded.
false	Registration failed.