satcat5::tcp::Header Struct Reference

Detailed Description

TCP header contents.

See also

tcp_core.h.

Definition at line 34 of file tcp_core.h.

#include <tcp_core.h>

Public Member Functions
	Header (const Header &t)=default
Header &	operator= (const Header &t)=default
constexpr satcat5::tcp::Port	src () const
	< Source port
constexpr satcat5::tcp::Port	dst () const
	< Destination port
constexpr unsigned	ihl () const
	< Header length (4-byte words)
constexpr u16	chk () const
	< Checksum (incoming only)
void	chk_incr16 (u16 prev, u16 next)
	Incremental update to checksum by replacing a given field. More...
void	chk_incr32 (u32 prev, u32 next)
void	write_to (satcat5::io::Writeable *wr) const
	Write TCP header to the designated stream.
bool	read_core (satcat5::io::Readable *rd)
	Read a partial TCP header from the designated stream. More...
bool	read_from (satcat5::io::Readable *rd)
	Read TCP header from the designated stream. More...

Public Attributes
u16	data [HDR_MAX_SHORTS]
	Raw access to the underlying header contents.

Member Function Documentation

chk_incr16()

void Header::chk_incr16	(	u16	prev,
		u16	next
	)

Incremental update to checksum by replacing a given field.

The before/after values can any location in the TCP psuedo-header Uses the ~m + m' method of RFC1624 Section 3.

Definition at line 12 of file tcp_core.cc.

read_core()

bool Header::read_core

(

satcat5::io::Readable *

rd

)

Read a partial TCP header from the designated stream.

This method reads the first 20 bytes of a TCP header, which contains basic header fields but not variable-length options (i.e., OFFSET > 5). This is used in cases where the full header is unavailable or unnecessary (e.g., due to "peek" limits). To read the entire TCP checksum,

See also

read_from.

Returns

True if the partial header is valid, false otherwise.

Definition at line 30 of file tcp_core.cc.

read_from()

bool Header::read_from

(

satcat5::io::Readable *

rd

)

Read TCP header from the designated stream.

This method calls read_core, then reads variable-length header options up to the start of user data. It does not validate the TCP checksum.

Returns

True if header is valid, false otherwise.

Definition at line 42 of file tcp_core.cc.

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The documentation for this struct was generated from the following files:

• tcp_core.h
• tcp_core.cc