util Namespace Reference

The utility namespace. More...

Functions
void	clear ()
	Clear the screen.
template<typename T = bool>
T	input (const std::string &title, const T &error_ret=T())
	std::cin can be a little difficult to use, particularly handling bad input. This sanitized it.
void	prompt (const std::string &message)
	Prompt the user and wait until they have confirmed it.
void	construct_shared_key (std::array< uint64_t, 4 > &sk, const bool &server)
	Genreate a shared key over a connection.
void	receive_message (const std::array< uint64_t, 4 > &sk)
	Receive an encrypted message from the peer.
void	send_message (const std::array< uint64_t, 4 > &sk)
	Send an encrypted message to a peer.
bool	acknowledge (const std::string &what)
	Acknowledge a request from a peer.

Detailed Description

The utility namespace.

Remarks

A namespace isn't really necessary, since this is only used by main, but it allows Doxygen to document these functions on the HTML.

Function Documentation

acknowledge()

bool util::acknowledge

(

const std::string &

what

)

Acknowledge a request from a peer.

Parameters

what	What is the acknowledgement for?

Returns

The return code of the send_packet.

clear()

void util::clear ( )

inline

Clear the screen.

Remarks

This works on UNIX/Windows. It's a shell escape sequence.

construct_shared_key()

void util::construct_shared_key	(	std::array< uint64_t, 4 > &	sk,
		const bool &	server )

Genreate a shared key over a connection.

Parameters

sk	The shared key array to populate.
server	Whether we are the server or not.

Remarks

AES requires key sizes of 128, 192, or 256 bits, but our uint64_t is just 64. So, we just perform 4 key exchanges to get 256 bits.

Warning

Selecting different modes of AES merely truncates this key (IE AES-128 uses sk[0,1], AES-192 uses sk[0,1,2], AES-256 uses all of them).

This is not the cryptographically secure way of doing things. We should almost certainly Exchange a single, massive 256 bit prime instead of four 64 bit ones, but for the sake of not needing to create our own 256 bit number classes, we just key exchange quadrice.

input()

template<typename T = bool>

T util::input ( const std::string & title, const T & error_ret = T() )

inline

std::cin can be a little difficult to use, particularly handling bad input. This sanitized it.

Template Parameters

T	The type of input to be returned.

Parameters

title	A title to be drawn for the input
error_ret	If something causes an error, what we should return to let the caller know.

Returns

The user input, or the error return.

Remarks

This function does not re-prompt upon errors; it is the responsibility of the caller to check for the error return and act accordingly.

Warning

This function is blocking.

prompt()

void util::prompt ( const std::string & message )

inline

Prompt the user and wait until they have confirmed it.

Parameters

message

The message to display.

Warning

This function is blocking.

receive_message()

void util::receive_message

(

const std::array< uint64_t, 4 > &

sk

)

Receive an encrypted message from the peer.

Parameters

sk	The shared key

send_message()

void util::send_message

(

const std::array< uint64_t, 4 > &

sk

)

Send an encrypted message to a peer.

Parameters

sk	The shared key.