gnrc_tcp_pkt.h File Reference

TCP packet handling declarations. More...

Detailed Description

TCP packet handling declarations.

Author

Simon Brummer simon.nosp@m..bru.nosp@m.mmer@.nosp@m.post.nosp@m.eo.de

Definition in file gnrc_tcp_pkt.h.

#include <stdint.h>
#include "net/gnrc.h"
#include "net/gnrc/tcp/tcb.h"

Include dependency graph for gnrc_tcp_pkt.h:

Go to the source code of this file.

int	_gnrc_tcp_pkt_build_reset_from_pkt (gnrc_pktsnip_t **out_pkt, gnrc_pktsnip_t *in_pkt)
	Build a reset packet from an incoming packet. More...
int	_gnrc_tcp_pkt_build (gnrc_tcp_tcb_t *tcb, gnrc_pktsnip_t **out_pkt, uint16_t *seq_con, const uint16_t ctl, const uint32_t seq_num, const uint32_t ack_num, void *payload, const size_t payload_len)
	Build and allocate a TCB packet, TCB stores pointer to new packet. More...
int	_gnrc_tcp_pkt_send (gnrc_tcp_tcb_t *tcb, gnrc_pktsnip_t *out_pkt, const uint16_t seq_con, const bool retransmit)
	Sends packet to peer. More...
int	_gnrc_tcp_pkt_chk_seq_num (const gnrc_tcp_tcb_t *tcb, const uint32_t seq_num, const uint32_t seg_len)
	Verify sequence number. More...
uint32_t	_gnrc_tcp_pkt_get_seg_len (gnrc_pktsnip_t *pkt)
	Extracts the length of a segment. More...
uint32_t	_gnrc_tcp_pkt_get_pay_len (gnrc_pktsnip_t *pkt)
	Calculates a packets payload length. More...
int	_gnrc_tcp_pkt_setup_retransmit (gnrc_tcp_tcb_t *tcb, gnrc_pktsnip_t *pkt, const bool retransmit)
	Adds a packet to the retransmission mechanism. More...
int	_gnrc_tcp_pkt_acknowledge (gnrc_tcp_tcb_t *tcb, const uint32_t ack)
	Acknowledges and removes packet from the retransmission mechanism. More...
uint16_t	_gnrc_tcp_pkt_calc_csum (const gnrc_pktsnip_t *hdr, const gnrc_pktsnip_t *pseudo_hdr, const gnrc_pktsnip_t *payload)
	Calculates checksum over payload, TCP header and network layer header. More...

Function Documentation

_gnrc_tcp_pkt_acknowledge()

int _gnrc_tcp_pkt_acknowledge	(	gnrc_tcp_tcb_t *	tcb,
		const uint32_t	ack
	)

Acknowledges and removes packet from the retransmission mechanism.

Parameters

[in,out]	tcb	TCB holding the connection information.
[in]	ack	Acknowldegment number used to acknowledge packets.

Returns

Zero on success. -ENODATA if there is nothing to acknowledge.

_gnrc_tcp_pkt_build()

int _gnrc_tcp_pkt_build	(	gnrc_tcp_tcb_t *	tcb,
		gnrc_pktsnip_t **	out_pkt,
		uint16_t *	seq_con,
		const uint16_t	ctl,
		const uint32_t	seq_num,
		const uint32_t	ack_num,
		void *	payload,
		const size_t	payload_len
	)

Build and allocate a TCB packet, TCB stores pointer to new packet.

Parameters

[in,out]	tcb	TCB holding the connection information.
[out]	out_pkt	Pointer to packet to build.
[out]	seq_con	Sequence number consumption of built packet.
[in]	ctl	Control bits to set in out_pkt.
[in]	seq_num	Sequence number of the new packet.
[in]	ack_num	Acknowledgment number of the new packet.
[in]	payload	Pointer to payload buffer.
[in]	payload_len	Payload size.

Returns

Zero on success. -ENOMEM if pktbuf is full.

_gnrc_tcp_pkt_build_reset_from_pkt()

int _gnrc_tcp_pkt_build_reset_from_pkt	(	gnrc_pktsnip_t **	out_pkt,
		gnrc_pktsnip_t *	in_pkt
	)

Build a reset packet from an incoming packet.

Note

This function builds a reset from an incoming packet in cases where the connection has not been established.

Parameters

[out]	out_pkt	Outgoing reset packet
[in]	in_pkt	Incoming packet

Returns

Zero on success -ENOMEM if pktbuf is full.

_gnrc_tcp_pkt_calc_csum()

uint16_t _gnrc_tcp_pkt_calc_csum	(	const gnrc_pktsnip_t *	hdr,
		const gnrc_pktsnip_t *	pseudo_hdr,
		const gnrc_pktsnip_t *	payload
	)

Calculates checksum over payload, TCP header and network layer header.

Parameters

[in]	hdr	Gnrc_pktsnip_t to TCP header.
[in]	pseudo_hdr	Gnrc_pktsnip_t to network layer header.
[in]	payload	Gnrc_pktsnip_t to payload.

Returns

Non-zero checksum if given network layer is supported. Zero if given network layer is not supported.

_gnrc_tcp_pkt_chk_seq_num()

int _gnrc_tcp_pkt_chk_seq_num	(	const gnrc_tcp_tcb_t *	tcb,
		const uint32_t	seq_num,
		const uint32_t	seg_len
	)

Verify sequence number.

Parameters

[in,out]	tcb	TCB holding the connection information.
[in]	seq_num	Sequence number from the segment.
[in]	seg_len	Length of a segments payload.

Returns

Zero if the sequence number is acceptable. Negative value if the sequence number is not acceptable.

_gnrc_tcp_pkt_get_pay_len()

uint32_t _gnrc_tcp_pkt_get_pay_len

(

gnrc_pktsnip_t *

pkt

)

Calculates a packets payload length.

Parameters

[in]

pkt

Packet to calculate payload length.

Returns

The packets payload length in bytes.

_gnrc_tcp_pkt_get_seg_len()

uint32_t _gnrc_tcp_pkt_get_seg_len

(

gnrc_pktsnip_t *

pkt

)

Extracts the length of a segment.

Parameters

[in]

pkt

Packet to calculate the segments length.

Returns

Segments length in bytes (== sequence number consumption).

_gnrc_tcp_pkt_send()

int _gnrc_tcp_pkt_send	(	gnrc_tcp_tcb_t *	tcb,
		gnrc_pktsnip_t *	out_pkt,
		const uint16_t	seq_con,
		const bool	retransmit
	)

Sends packet to peer.

Parameters

[in,out]	tcb	TCB holding the connection information.
[in]	out_pkt	Pointer to packet to send.
[in]	seq_con	Sequence number consumption of the packet to send.
[in]	retransmit	Flag so mark that packet this is a retransmission.

Returns

Zero on success. -EINVAL if out_pkt was NULL.

_gnrc_tcp_pkt_setup_retransmit()

int _gnrc_tcp_pkt_setup_retransmit	(	gnrc_tcp_tcb_t *	tcb,
		gnrc_pktsnip_t *	pkt,
		const bool	retransmit
	)

Adds a packet to the retransmission mechanism.

Parameters

[in,out]	tcb	TCB holding the connection information.
[in]	pkt	Packet to add to the retransmission mechanism.
[in]	retransmit	Flag used to indicate that pkt is a retransmit.

Returns

Zero on success. -ENOMEM if the retransmission queue is full. -EINVAL if pkt is null.