#include <genl.hpp>

Inheritance diagram for openvpn::GeNL< ReadHandler >:

Collaboration diagram for openvpn::GeNL< ReadHandler >:

Classes
struct	mcast_handler_args

Public Types
typedef RCPtr< GeNL >	Ptr

Public Types inherited from openvpn::RC< thread_unsafe_refcount >
typedef RCPtr< RC >	Ptr

Public Member Functions
	GeNL (openvpn_io::io_context &io_context, unsigned int ifindex_arg, ReadHandler read_handler_arg)

void	new_peer (int peer_id, int fd, struct sockaddr *sa, socklen_t salen, IPv4::Addr vpn4, IPv6::Addr vpn6)

void	new_key (unsigned int key_slot, const KoRekey::KeyConfig *kc)

void	swap_keys (int peer_id)

void	del_key (int peer_id, unsigned int key_slot)

void	set_peer (int peer_id, unsigned int keepalive_interval, unsigned int keepalive_timeout)

void	del_peer (int peer_id)

void	get_peer (int peer_id, bool sync)

void	stop ()

Public Member Functions inherited from openvpn::RC< thread_unsafe_refcount >
	RC () noexcept=default

	RC (const RC &)=delete

virtual	~RC ()=default

RC &	operator= (const RC &)=delete

olong	use_count () const noexcept
	Delegates call to RCImpl and returns the result.

Static Public Member Functions
static bool	available ()

Static Public Member Functions inherited from openvpn::RC< thread_unsafe_refcount >
static constexpr bool	is_thread_safe ()
	Delegates call to RCImpl and returns the result.

Private Types
typedef std::unique_ptr< nl_msg, decltype(&nlmsg_free)>	NlMsgPtr

typedef std::unique_ptr< nl_sock, decltype(&nl_socket_free)>	NlSockPtr

typedef std::unique_ptr< nl_cb, decltype(&nl_cb_put)>	NlCbPtr

Private Member Functions
	OPENVPN_EXCEPTION (netlink_error)

int	get_mcast_id ()

void	handle_read (const openvpn_io::error_code &error)

void	queue_genl_read ()

NlMsgPtr	create_msg (enum ovpn_nl_commands cmd)

void	read_netlink_message ()

void	reset_buffer ()

void	send_netlink_message (struct nl_msg *msg)

Static Private Member Functions
static int	mcast_family_handler (struct nl_msg msg, void arg)

static int	message_received (struct nl_msg msg, void arg)

static int	ovpn_nl_cb_error (struct sockaddr_nl nla, struct nlmsgerr err, void *arg)

Private Attributes
NlSockPtr	sock_ptr

NlCbPtr	cb_ptr

struct nl_sock *	sock

struct nl_cb *	cb

int	ovpn_dco_id

unsigned int	ifindex

ReadHandler	read_handler

bool	halt

BufferAllocated	buf

std::unique_ptr< openvpn_io::posix::stream_descriptor >	stream

Static Private Attributes
static int	nl_status = 0

Detailed Description

template<typename ReadHandler>
class openvpn::GeNL< ReadHandler >

Implements asynchronous communication with ovpn-dco kernel module via generic netlink protocol.

Before using this class, caller should create ovpn-dco network device.

Template Parameters

ReadHandler

class which implements tun_read_handler(BufferAllocated &buf) method.
buf has following layout:

first byte - command type ( OVPN_CMD_DEL_PEER or -1 for error)
following bytes - command-specific payload

Definition at line 77 of file genl.hpp.

Member Typedef Documentation

◆ NlCbPtr

template<typename ReadHandler >

typedef std::unique_ptr<nl_cb, decltype(&nl_cb_put)> openvpn::GeNL< ReadHandler >::NlCbPtr

private

Definition at line 83 of file genl.hpp.

◆ NlMsgPtr

template<typename ReadHandler >

typedef std::unique_ptr<nl_msg, decltype(&nlmsg_free)> openvpn::GeNL< ReadHandler >::NlMsgPtr

private

Definition at line 81 of file genl.hpp.

◆ NlSockPtr

template<typename ReadHandler >

typedef std::unique_ptr<nl_sock, decltype(&nl_socket_free)> openvpn::GeNL< ReadHandler >::NlSockPtr

private

Definition at line 82 of file genl.hpp.

◆ Ptr

template<typename ReadHandler >

typedef RCPtr<GeNL> openvpn::GeNL< ReadHandler >::Ptr

Definition at line 86 of file genl.hpp.

Constructor & Destructor Documentation

◆ GeNL()

template<typename ReadHandler >

openvpn::GeNL< ReadHandler >::GeNL	(	openvpn_io::io_context &	io_context,
		unsigned int	ifindex_arg,
		ReadHandler	read_handler_arg
	)

inlineexplicit

Construct a new GeNL object

Parameters

io_context	reference to io_context
ifindex_arg	index of ovpn-dco network device
read_handler_arg	instance of `ReadHandler`

Exceptions

netlink_error thrown if error occurs during initialization

Definition at line 112 of file genl.hpp.

Member Function Documentation

◆ available()

template<typename ReadHandler >

static bool openvpn::GeNL< ReadHandler >::available ( )

inlinestatic

Detect ovpn-dco kernel module

Returns: bool value indicating whether the module is loaded

Definition at line 93 of file genl.hpp.

◆ create_msg()

template<typename ReadHandler >

NlMsgPtr openvpn::GeNL< ReadHandler >::create_msg ( enum ovpn_nl_commands cmd )

inlineprivate

Definition at line 593 of file genl.hpp.

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◆ del_key()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::del_key	(	int	peer_id,
		unsigned int	key_slot
	)

inline

Remove key from key slot.

Parameters

peer_id	the ID of the peer whose keys has to be deleted
key_slot	OVPN_KEY_SLOT_PRIMARY or OVPN_KEY_SLOT_SECONDARY

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 306 of file genl.hpp.

◆ del_peer()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::del_peer ( int peer_id )

inline

Delete an existing peer.

Parameters

peer_id the ID of the peer to delete

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 363 of file genl.hpp.

◆ get_mcast_id()

template<typename ReadHandler >

int openvpn::GeNL< ReadHandler >::get_mcast_id ( )

inlineprivate

Return id of multicast group which ovpn-dco uses to broadcast OVPN_CMD_DEL_PEER message

Returns: int multicast group id

Definition at line 501 of file genl.hpp.

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◆ get_peer()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::get_peer	(	int	peer_id,
		bool	sync
	)

inline

Retrieve he current status of a peer.

Parameters

peer_id	the ID of the peer to query
sync	When true the method waits for the reply before returning

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 389 of file genl.hpp.

◆ handle_read()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::handle_read ( const openvpn_io::error_code & error )

inlineprivate

Definition at line 552 of file genl.hpp.

◆ mcast_family_handler()

template<typename ReadHandler >

static int openvpn::GeNL< ReadHandler >::mcast_family_handler	(	struct nl_msg *	msg,
		void *	arg
	)

inlinestaticprivate

This callback is called by libnl. Here we enumerate netlink multicast groups and find id of the one which name matches ovpn-dco multicast group.

Parameters

msg	netlink message to be processed
arg	arguments passed by nl_cb_set() call

Returns: int id of ovpn-dco multicast group

Definition at line 458 of file genl.hpp.

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◆ message_received()

template<typename ReadHandler >

static int openvpn::GeNL< ReadHandler >::message_received	(	struct nl_msg *	msg,
		void *	arg
	)

inlinestaticprivate

This is called inside libnl's nl_recvmsgs() call to process incoming netlink message.

Parameters

msg	netlink message to be processed
arg	argument passed by `nl_cb_set()`

Returns: int callback action

Definition at line 634 of file genl.hpp.

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◆ new_key()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::new_key	(	unsigned int	key_slot,
		const KoRekey::KeyConfig *	kc
	)

inline

Inject new key into kernel module

Parameters

key_slot	OVPN_KEY_SLOT_PRIMARY or OVPN_KEY_SLOT_SECONDARY
kc	pointer to KeyConfig struct which contains key data

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 220 of file genl.hpp.

◆ new_peer()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::new_peer	(	int	peer_id,
		int	fd,
		struct sockaddr *	sa,
		socklen_t	salen,
		IPv4::Addr	vpn4,
		IPv6::Addr	vpn6
	)

inline

Add peer information to kernel module

Parameters

peer_id	Peer ID of the peer being created
fd	socket to be used to communicate with the peer
sa	sockaddr object representing the remote endpoint
salen	length of sa (either sizeof(sockaddr_in) or sizeof(sockaddr_in6)
vpn4	IPv4 address associated with this peer in the tunnel
vpn6	IPv6 address associated with this peer in the tunnel

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 178 of file genl.hpp.

◆ OPENVPN_EXCEPTION()

template<typename ReadHandler >

openvpn::GeNL< ReadHandler >::OPENVPN_EXCEPTION ( netlink_error )

private

◆ ovpn_nl_cb_error()

template<typename ReadHandler >

static int openvpn::GeNL< ReadHandler >::ovpn_nl_cb_error	(	struct sockaddr_nl *	nla,
		struct nlmsgerr *	err,
		void *	arg
	)

inlinestaticprivate

This is an error callback called by netlink for error message processing customization.

Parameters

nla	netlink address of the peer (value not needed here)
err	netlink error message being processed
arg	argument passed by `nl_cb_err()`

Returns: int callback action

Definition at line 767 of file genl.hpp.

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◆ queue_genl_read()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::queue_genl_read ( )

inlineprivate

Definition at line 584 of file genl.hpp.

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◆ read_netlink_message()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::read_netlink_message ( )

inlineprivate

Definition at line 604 of file genl.hpp.

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◆ reset_buffer()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::reset_buffer ( )

inlineprivate

Definition at line 752 of file genl.hpp.

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◆ send_netlink_message()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::send_netlink_message ( struct nl_msg * msg )

inlineprivate

Definition at line 802 of file genl.hpp.

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◆ set_peer()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::set_peer	(	int	peer_id,
		unsigned int	keepalive_interval,
		unsigned int	keepalive_timeout
	)

inline

Set peer properties. Currently used for keepalive settings.

Parameters

peer_id	ID of the peer whose properties have to be modified
keepalive_interval	how often to send ping packet in absence of traffic
keepalive_timeout	when to trigger keepalive_timeout in absence of traffic

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 336 of file genl.hpp.

◆ stop()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::stop ( )

inline

Definition at line 419 of file genl.hpp.

◆ swap_keys()

template<typename ReadHandler >

void openvpn::GeNL< ReadHandler >::swap_keys ( int peer_id )

inline

Swap keys between primary and secondary slots. Called by client as part of rekeying logic to promote and demote keys.

Parameters

peer_id the ID of the peer whose keys have to be swapped

Exceptions

netlink_error thrown if error occurs during sending netlink message

Definition at line 280 of file genl.hpp.

Member Data Documentation

◆ buf

template<typename ReadHandler >

BufferAllocated openvpn::GeNL< ReadHandler >::buf

private

Definition at line 824 of file genl.hpp.

◆ cb

template<typename ReadHandler >

struct nl_cb* openvpn::GeNL< ReadHandler >::cb

private

Definition at line 816 of file genl.hpp.

◆ cb_ptr

template<typename ReadHandler >

NlCbPtr openvpn::GeNL< ReadHandler >::cb_ptr

private

Definition at line 813 of file genl.hpp.

◆ halt

template<typename ReadHandler >

bool openvpn::GeNL< ReadHandler >::halt

private

Definition at line 823 of file genl.hpp.

◆ ifindex

template<typename ReadHandler >

unsigned int openvpn::GeNL< ReadHandler >::ifindex

private

Definition at line 819 of file genl.hpp.

◆ nl_status

template<typename ReadHandler >

int openvpn::GeNL< ReadHandler >::nl_status = 0

staticprivate

Definition at line 827 of file genl.hpp.

◆ ovpn_dco_id

template<typename ReadHandler >

int openvpn::GeNL< ReadHandler >::ovpn_dco_id

private

Definition at line 818 of file genl.hpp.

◆ read_handler

template<typename ReadHandler >

ReadHandler openvpn::GeNL< ReadHandler >::read_handler

private

Definition at line 821 of file genl.hpp.

◆ sock

template<typename ReadHandler >

struct nl_sock* openvpn::GeNL< ReadHandler >::sock

private

Definition at line 815 of file genl.hpp.

◆ sock_ptr

template<typename ReadHandler >

NlSockPtr openvpn::GeNL< ReadHandler >::sock_ptr

private

Definition at line 812 of file genl.hpp.

◆ stream

template<typename ReadHandler >

std::unique_ptr<openvpn_io::posix::stream_descriptor> openvpn::GeNL< ReadHandler >::stream

private

Definition at line 826 of file genl.hpp.

The documentation for this class was generated from the following file:

openvpn/tun/linux/client/genl.hpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Private Types

Private Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

Member Typedef Documentation

◆ NlCbPtr

◆ NlMsgPtr

◆ NlSockPtr

◆ Ptr

Constructor & Destructor Documentation

◆ GeNL()

Member Function Documentation

◆ available()

◆ create_msg()

◆ del_key()

◆ del_peer()

◆ get_mcast_id()

◆ get_peer()

◆ handle_read()

◆ mcast_family_handler()

◆ message_received()

◆ new_key()

◆ new_peer()

◆ OPENVPN_EXCEPTION()

◆ ovpn_nl_cb_error()

◆ queue_genl_read()

◆ read_netlink_message()

◆ reset_buffer()

◆ send_netlink_message()

◆ set_peer()

◆ stop()

◆ swap_keys()

Member Data Documentation

◆ buf

◆ cb

◆ cb_ptr

◆ halt

◆ ifindex

◆ nl_status

◆ ovpn_dco_id

◆ read_handler

◆ sock

◆ sock_ptr

◆ stream