Vkm::Engine::NetJoinCookie Class Reference

The token a server gives an address that asks to join, and takes back as proof that the address hears what is sent to it. More...

#include <join_cookie.h>

Public Member Functions
void	rekey ()
	Draw a new key from the operating system. Every token given before is void.
uint64_t	issue (const NetAddress &to, double now) const
	The token for to, as of now.
bool	accepts (const NetAddress &from, uint64_t token, double now) const
	Whether token is one issue() gave from, this window or the last.

Static Public Attributes
static constexpr double	WINDOW_SECONDS = 10.0
	How long one window lasts, in seconds; a token is good for one to two of them.

Detailed Description

The token a server gives an address that asks to join, and takes back as proof that the address hears what is sent to it.

Stateless - a keyed hash of the address and the time window - so a forged Hello costs a hash and a reply no larger, and crowds out no real join. Accepted for its window and the next. The key comes from the operating system, so tokens cannot be predicted and a restart voids them.

Member Function Documentation

issue()

uint64_t Vkm::Engine::NetJoinCookie::issue	(	const NetAddress &	to,
		double	now ) const

The token for to, as of now.

Parameters

to	The address that asked.
now	Seconds on a clock that only moves forward.

Returns

The token.

accepts()

bool Vkm::Engine::NetJoinCookie::accepts	(	const NetAddress &	from,
		uint64_t	token,
		double	now ) const

Whether token is one issue() gave from, this window or the last.

Parameters

from	The address the token came back from.
token	What it carried.
now	Seconds, on the clock issue() was given.

Returns

True when the token proves the address heard the Challenge.

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

• net/transport/join_cookie.h