src/vfer_packet.c File Reference

Implements packetizing and depacketizing functions. More...

#include "vfer_packet.h"

Go to the source code of this file.

Functions

static void Packet_Compute_Delay (char *pack_buf, struct timeval *tv, packet *p)

packet * Packet_Form_CCAck (uint32_t opts, uint32_t seq_num, uint32_t last_seq_received, uint16_t packets_lost, uint16_t oldest_frame, uint16_t newest_frame, int32_t delay_delta, int32_t delay, uint32_t bytes_total, uint16_t intervals_frame_num, intervals_t *intervals)

packet * Packet_Form_Close (uint32_t opts, uint32_t seq_num)

packet * Packet_Form_Data (uint32_t opts, uint32_t seq_num, uint16_t frame_num, uint32_t data_offset, uint32_t frame_len, void *data, int data_len)

packet * Packet_Form_Request (uint32_t opts, uint32_t init_seq_num, uint32_t max_frame_size, uint32_t recv_buf_size, uint32_t send_buf_size, uint16_t init_frame_num)

packet * Packet_Form_Response (uint32_t opts, uint32_t init_seq_num, uint16_t init_frame_num, uint16_t connection_port, uint32_t max_frame_size, uint32_t recv_buf_size, uint32_t send_buf_size, int32_t request_delay)

uint16_t Packet_Gen_FrameNum ()

uint32_t Packet_Gen_SeqNum ()

static void Packet_Get_Header (packet *p)

static int Packet_Get_Opt (uint32_t opts, int opt)

static void Packet_Get_Type (char *buf, unsigned char *type)

static void Packet_Get_Version (char *buf, unsigned char *version)

static packet * Packet_PrepIov (int num_bufs, int first_buf_len)

void Packet_Print (packet *p)

int Packet_Read (int fd, packet **p, struct sockaddr *addr, socklen_t *addr_len)

int Packet_Read_ICMP (int icmp_fd, void *pmtu)

static int Packet_Set_Header (packet *p, unsigned char type, uint32_t opts, uint32_t seq)

static void Packet_Set_Opt (uint32_t *opts, int opt)

void Packet_Set_Seq (packet *p, uint32_t seq)

char * Packet_Str (packet *p)

char * Packet_Str_Type (packet *p)

int Packet_Translate_CCAck (packet *p)

int Packet_Translate_Close (packet *p)

int Packet_Translate_Data (packet *p)

int Packet_Translate_Request (packet *p)

int Packet_Translate_Response (packet *p)

static void Packet_Unset_Opt (uint32_t *opts, int opt)

int Packet_Write (packet *p, int fd, struct sockaddr *addr, socklen_t addr_len)

Detailed Description

Implements packetizing and depacketizing functions.

Author:: Ivan Beschastnikh

This file contains usefull functions to compose and decompose packets. It also includes some handy utilities for printing packets out to stdout.

07/26/06 ivan removed vector ack packet type
12/28/05 ivan tsci2 integration ; Packet_Set_Header return value bug fix ; packet delay computing func coded
10/16/05 ivan added Packet_Seq_Set function
10/15/05 ivan bugfix of rand gen functions and byte ordering functions
09/01/05 ivan modified to use new packet structures ; coded packet printing functions
08/30/05 ivan use uint32_t for opts instead of char[3] ; added option interpretation and setting support ; added packet structs
08/29/05 ivan changed Packet_Read to take and set by ref an error argument
08/28/05 ivan added many new functions to do packet reading,writing,validation, seq and frame num generation
07/15/05 ivan new api packet print and form functions added
05/18/05 ivan created

Definition in file vfer_packet.c.

Function Documentation

static void Packet_Compute_Delay	(	char *	pack_buf,
		struct timeval *	tv,
		packet *	p
	)			`[inline, static]`

Computes the delay for a packet based on the raw packet buffer, sets the value computed in the packet structure and also extracts the time stamp from the raw packet buffer into the structure

Parameters:

	pack_buf	raw packet buffer
	tv	time structure marking receipt time for the packet
	p	packet structure for the packet buffer

Definition at line 717 of file vfer_packet.c.

packet* Packet_Form_CCAck	(	uint32_t	opts,
		uint32_t	seq_num,
		uint32_t	last_seq_received,
		uint16_t	packets_lost,
		uint16_t	oldest_frame,
		uint16_t	newest_frame,
		int32_t	delay_delta,
		int32_t	delay,
		uint32_t	bytes_total,
		uint16_t	intervals_frame_num,
		intervals_t *	intervals
	)

Forms a CC Ack packet

Parameters:

	opts	options for the generic header of the packet
	seq_num	sequence number for the generic header of the packet
	last_seq_received	last sequence number received by this connection
	packets_lost	estimated lost number of frags
	oldest_frame	oldest frame the received of this packet should resend
	newest_frame	oldest frame the received of this packet should resend
	delay_delta	current delay on the reverse path (not the path of this ack)
	delay	current delay for the reverse path
	bytes_total	total data bytes received by the endpoint
	intervals_frame_num	the frame number corresponding to the missing data intervals
	intervals	intervals structure (defined in datagram.h) If intervals->head == 0 then no intervals will be sent in the ack packet

Returns:: NULL on error pointer to an allocated packet on success

Definition at line 304 of file vfer_packet.c.

packet* Packet_Form_Close	(	uint32_t	opts,
		uint32_t	seq_num
	)

Forms a Close packet

Parameters:

	opts	options for the generic header of the packet
	seq_num	sequence number for the generic header of the packet

Returns:: NULL on error pointer to an allocated packet on success

Definition at line 417 of file vfer_packet.c.

packet* Packet_Form_Data	(	uint32_t	opts,
		uint32_t	seq_num,
		uint16_t	frame_num,
		uint32_t	data_offset,
		uint32_t	frame_len,
		void *	data,
		int	data_len
	)

Forms a Data packet

Parameters:

	opts	options for the generic header of the packet
	seq_num	sequence number for the generic header of the packet
	frame_num	frame number this data packet carries a frag for
	data_offset	offset of the data in the frame
	frame_len	either -1 (do not include in the data header) (opts will be set and send accordingly) or is not -1, in which case it is included in the data header
	data	data buffer to send in the body of the data packet
	data_len	tells us how the span of the data buffer pointed to by the data arg

Returns:: NULL on error pointer to an allocated packet on success

Definition at line 240 of file vfer_packet.c.

packet* Packet_Form_Request	(	uint32_t	opts,
		uint32_t	init_seq_num,
		uint32_t	max_frame_size,
		uint32_t	recv_buf_size,
		uint32_t	send_buf_size,
		uint16_t	init_frame_num
	)

Forms a Request packet

Parameters:

	opts	options for the generic header of the packet
	init_seq_num	initial sequence number for the sender's half of connection
	max_frame_size	maximum frame size the sender is willing to receive
	recv_buf_size	receive buffer size at the sender
	send_buf_size	sending buffer size at the sender
	init_frame_num	initial frame number for the sender's half of connection

Returns:: NULL on error pointer to an allocated packet on success

Definition at line 134 of file vfer_packet.c.

packet* Packet_Form_Response	(	uint32_t	opts,
		uint32_t	init_seq_num,
		uint16_t	init_frame_num,
		uint16_t	connection_port,
		uint32_t	max_frame_size,
		uint32_t	recv_buf_size,
		uint32_t	send_buf_size,
		int32_t	request_delay
	)

Forms a Response packet

Parameters:

	opts	options for the generic header of the packet
	init_seq_num	initial sequence number for the sender's half of connection
	init_frame_num	initial frame number for the sender's half of connection
	connection_port	the connection port to which the sender should connect and use for the remained of this connection
	max_frame_size	maximum frame size the sender is willing to receive
	recv_buf_size	receive buffer size at the sender
	send_buf_size	sending buffer size at the sender
	request_delay	the delay computed for the request packet

Returns:: NULL on error pointer to an allocated packet on success

Definition at line 183 of file vfer_packet.c.

uint16_t Packet_Gen_FrameNum ( ) [inline]

Generates a random (2 bytes) frame number

Returns:: generated frame number

Definition at line 1037 of file vfer_packet.c.

uint32_t Packet_Gen_SeqNum ( ) [inline]

Generates a random (4 byte) sequence number.

Returns:: generated sequence number

Definition at line 1048 of file vfer_packet.c.

static void Packet_Get_Header ( packet * p ) [inline, static]

Gets the packet header from a packet buffer and writes into the packet structure

Parameters:

pointer to the packet in which get and get the header

Definition at line 659 of file vfer_packet.c.

static int Packet_Get_Opt	(	uint32_t	opts,
		int	opt
	)			`[inline, static]`

Boolean function that checks if an option is set

Parameters:

	opts	options pointer
	opt	option to check for

Returns:: 0 if option is not set 1 if the option is set

Definition at line 1091 of file vfer_packet.c.

static void Packet_Get_Type	(	char *	buf,
		unsigned char *	type
	)			`[inline, static]`

Extracts the type in a bufer interpreted as packet header

Parameters:

	buf	packet buffer
	type	reference arg type of packet

Definition at line 686 of file vfer_packet.c.

static void Packet_Get_Version	(	char *	buf,
		unsigned char *	version
	)			`[inline, static]`

Extracts the version in a buffer interpreted as packet header

Parameters:

	buf	packet buffer
	version	reference argument into which the version will be stored

Definition at line 700 of file vfer_packet.c.

static packet * Packet_PrepIov	(	int	num_bufs,
		int	first_buf_len
	)			`[inline, static]`

Prepares the iov strucutre for a packet

Parameters:

	num_bufs	number of iov buffers to allocate
	first_buf_len	length of the first buffer to allocate

Returns:: NULL on error newly allocated packet pointer with allocated buffers

Definition at line 748 of file vfer_packet.c.

void Packet_Print ( packet * p )

Prints a description of the packet onto stdout

Parameters:

packet pointer

Definition at line 107 of file vfer_packet.c.

int Packet_Read	(	int	fd,
		packet **	p,
		struct sockaddr *	addr,
		socklen_t *	addr_len
	)

Reads from a file descriptor into an iov buffer.

Does minor validation of the generic header. Returns either an error or the packet_type of the received packet. Set iov as return by reference.

Parameters:

	fd	file descriptor to which to write the buffer
	p	packet strucutre to read the packet into
	addr	pointer that is either NULL or address to which we send the iov
	addr_len	pointer to be set by reference to length of addr param

Returns:: 0 on success (p contains a valid packet) errno on syscall error -1 received packet has incorrect length (validation err) -2 received packet has incorrect type (validation err) -3 received packet has incorrect version (validation err) -4 on unknown packet type -5 on error (shutdown socket) -6 on error (ALLOC macro) -7 on error (other) - such as mismatched recv sizes (see below)

Definition at line 789 of file vfer_packet.c.

int Packet_Read_ICMP	(	int	icmp_fd,
		void *	pmtu
	)

Reads ICMP packets and makes any necessary adjustments to the path MTU.

Parameters:

	icmp_fd	file descriptor of icmp socket
	pmtu	pmtu structure to modify if we read an ICMP packet

Returns:: 0 on success (p contains a valid packet) -1 no ICMP packets to be read

Definition at line 913 of file vfer_packet.c.

static int Packet_Set_Header	(	packet *	p,
		unsigned char	type,
		uint32_t	opts,
		uint32_t	seq
	)			`[inline, static]`

Sets the packet header into a packet buffer

Parameters:

	p	pointer to the packet in which to set the header
	type	type of packet
	opts	opts to store in packet
	seq	sequence number to set in packet

Returns:: number of bytes of buf that are used by the header

Definition at line 637 of file vfer_packet.c.

static void Packet_Set_Opt	(	uint32_t *	opts,
		int	opt
	)			`[inline, static]`

Sets an option in an options pointer

Parameters:

	opts	options pointer
	opt	option to set

Definition at line 1063 of file vfer_packet.c.

void Packet_Set_Seq	(	packet *	p,
		uint32_t	seq
	)			`[inline]`

Sets the sequence number in the packet header

Parameters:

	p	pointer to the packet in which to set the header
	seq	sequence number to set in the header

Definition at line 618 of file vfer_packet.c.

char* Packet_Str ( packet * p )

Create a string description of the packet

Parameters:

packet pointer

Returns:: string describing the packet parameter

Definition at line 75 of file vfer_packet.c.

char* Packet_Str_Type ( packet * p )

String type of packet

Parameters:

packet pointer

Returns:: string describing the type of the packet parameter

Definition at line 53 of file vfer_packet.c.

int Packet_Translate_CCAck ( packet * p )

Fills in the cc_ack union memeber with values from a raw packet

Parameters:

packet pointer to traslate

Returns:: 0 on success -1 packet with incorrect length

Definition at line 543 of file vfer_packet.c.

int Packet_Translate_Close ( packet * p )

Fills in the close union memeber with values from a raw packet

Parameters:

packet pointer to traslate

Returns:: 0 on success -1 packet with incorrect length

Definition at line 601 of file vfer_packet.c.

int Packet_Translate_Data ( packet * p )

Fills in the data union memeber with values from a raw packet

Parameters:

packet pointer to traslate

Returns:: 0 on success -1 packet with incorrect length

Definition at line 502 of file vfer_packet.c.

int Packet_Translate_Request ( packet * p )

Fills in the request union memeber with values from a raw packet

Parameters:

packet pointer to traslate

Returns:: 0 on success -1 packet with incorrect length

Definition at line 437 of file vfer_packet.c.

int Packet_Translate_Response ( packet * p )

Fills in the response union memeber with values from a raw packet

Parameters:

packet pointer to traslate

Returns:: 0 on success -1 packet with incorrect length

Definition at line 466 of file vfer_packet.c.

static void Packet_Unset_Opt	(	uint32_t *	opts,
		int	opt
	)			`[inline, static]`

Unsets an option in an options pointer

Parameters:

	opts	options pointer
	opt	option to unset

Definition at line 1075 of file vfer_packet.c.

int Packet_Write	(	packet *	p,
		int	fd,
		struct sockaddr *	addr,
		socklen_t	addr_len
	)

Writes a packet of a certain length to a file descriptor.

Parameters:

	p	packet structure containing the packet to write out
	fd	file descriptor to which to write the buffer
	addr	is the address to send the packet to (eg. for unconnected sockets - used in server.c Server_Accept() )
	addr_len	is the length of the addr param

Returns:: 0 on success errno generated by sendmsg or writev on error

Definition at line 956 of file vfer_packet.c.

Generated on Tue Aug 8 16:07:21 2006 for VFER by

1.4.7


Functions
static void	Packet_Compute_Delay (char pack_buf, struct timeval tv, packet *p)
packet *	Packet_Form_CCAck (uint32_t opts, uint32_t seq_num, uint32_t last_seq_received, uint16_t packets_lost, uint16_t oldest_frame, uint16_t newest_frame, int32_t delay_delta, int32_t delay, uint32_t bytes_total, uint16_t intervals_frame_num, intervals_t *intervals)
packet *	Packet_Form_Close (uint32_t opts, uint32_t seq_num)
packet *	Packet_Form_Data (uint32_t opts, uint32_t seq_num, uint16_t frame_num, uint32_t data_offset, uint32_t frame_len, void *data, int data_len)
packet *	Packet_Form_Request (uint32_t opts, uint32_t init_seq_num, uint32_t max_frame_size, uint32_t recv_buf_size, uint32_t send_buf_size, uint16_t init_frame_num)
packet *	Packet_Form_Response (uint32_t opts, uint32_t init_seq_num, uint16_t init_frame_num, uint16_t connection_port, uint32_t max_frame_size, uint32_t recv_buf_size, uint32_t send_buf_size, int32_t request_delay)
uint16_t	Packet_Gen_FrameNum ()
uint32_t	Packet_Gen_SeqNum ()
static void	Packet_Get_Header (packet *p)
static int	Packet_Get_Opt (uint32_t opts, int opt)
static void	Packet_Get_Type (char buf, unsigned char type)
static void	Packet_Get_Version (char buf, unsigned char version)
static packet *	Packet_PrepIov (int num_bufs, int first_buf_len)
void	Packet_Print (packet *p)
int	Packet_Read (int fd, packet *p, struct sockaddr addr, socklen_t *addr_len)
int	Packet_Read_ICMP (int icmp_fd, void *pmtu)
static int	Packet_Set_Header (packet *p, unsigned char type, uint32_t opts, uint32_t seq)
static void	Packet_Set_Opt (uint32_t *opts, int opt)
void	Packet_Set_Seq (packet *p, uint32_t seq)
char *	Packet_Str (packet *p)
char *	Packet_Str_Type (packet *p)
int	Packet_Translate_CCAck (packet *p)
int	Packet_Translate_Close (packet *p)
int	Packet_Translate_Data (packet *p)
int	Packet_Translate_Request (packet *p)
int	Packet_Translate_Response (packet *p)
static void	Packet_Unset_Opt (uint32_t *opts, int opt)
int	Packet_Write (packet p, int fd, struct sockaddr addr, socklen_t addr_len)