#include "wtap.h"

Functions
unsigned	wtap_max_snaplen_for_encap (int wtap_encap)
	Get the maximum snapshot length for a given capture encapsulation type.

int	pcap_process_pseudo_header (FILE_T fh, bool is_nokia, int wtap_encap, unsigned packet_size, wtap_rec rec, int err, char **err_info)
	Reads and processes the pseudo-header for a pcap packet record.

void	pcap_read_post_process (bool is_nokia, int wtap_encap, wtap_rec *rec, bool bytes_swapped, int fcs_len)
	Performs post-read fixups on a pcap packet record.

unsigned	pcap_get_phdr_size (int encap, const union wtap_pseudo_header *pseudo_header)
	Retrieves the size of the pseudo-header for a given encapsulation type and pseudo-header.

bool	pcap_write_phdr (wtap_dumper wdh, int wtap_encap, const union wtap_pseudo_header pseudo_header, int *err)
	Writes a packet header to a dump file.

Detailed Description

Declarations for code common to pcap and pcapng file formats

SPDX-License-Identifier: GPL-2.0-or-later

Function Documentation

unsigned pcap_get_phdr_size	(	int	encap,
		const union wtap_pseudo_header *	pseudo_header
	)

extern

Retrieves the size of the pseudo-header for a given encapsulation type and pseudo-header.

Parameters

encap	The encapsulation type.
pseudo_header	Pointer to the pseudo-header union.

int pcap_process_pseudo_header	(	FILE_T	fh,
		bool	is_nokia,
		int	wtap_encap,
		unsigned	packet_size,
		wtap_rec *	rec,
		int *	err,
		char **	err_info
	)

extern

Reads and processes the pseudo-header for a pcap packet record.

Parameters

fh	File handle positioned immediately after the pcap record header, at the start of any pseudo-header data.
is_nokia	`true` if the file is a Nokia-variant pcap file, which uses a different pseudo-header layout.
wtap_encap	Wiretap encapsulation type for this packet, used to select the correct pseudo-header format to read.
packet_size	Total captured packet size in bytes including any pseudo-header; used for bounds checking.
rec	wtap record structure whose pseudo-header fields are populated by this function.
err	Set to a Wiretap or UNIX errno error code on failure.
err_info	Set to a newly allocated error detail string on failure; the caller is responsible for freeing it.

Returns: Number of pseudo-header bytes consumed on success; -1 on failure, with err and err_info set.

extern

Performs post-read fixups on a pcap packet record.

Parameters

is_nokia	`true` if the file is a Nokia-variant pcap file, which requires Nokia-specific fixups.
wtap_encap	Wiretap encapsulation type for this packet, used to determine which fields require post-processing.
rec	wtap record structure to fix up in-place.
bytes_swapped	`true` if the pcap file was written by a host with the opposite byte order, requiring byte-swapping of multi-byte pseudo-header fields.
fcs_len	Frame Check Sequence length in bytes as recorded in the pcap file header; -1 if unknown.

bool pcap_write_phdr	(	wtap_dumper *	wdh,
		int	wtap_encap,
		const union wtap_pseudo_header *	pseudo_header,
		int *	err
	)

extern

Writes a packet header to a dump file.

Parameters

wdh	Pointer to the wtap_dumper structure.
wtap_encap	The encapsulation type of the packet.
pseudo_header	Pointer to the pseudo-header of the packet.
err	Pointer to an integer where any error code will be stored.

unsigned wtap_max_snaplen_for_encap ( int wtap_encap )

extern

Get the maximum snapshot length for a given capture encapsulation type.

Parameters

wtap_encap The capture encapsulation type.

Returns: unsigned The maximum snapshot length for the specified encapsulation type.