ip_header.h File Reference

IP header and options definitions. More...

#include <byteorder.h>
#include <sys/types.h>

Include dependency graph for ip_header.h:

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Data Structures
struct	ip_header
	Internet header. More...
struct	ip_option
	Internet option header. More...
struct	ipv4_pseudo_header
	Internet version 4 pseudo header. More...
Defines
#define	IP_COMPUTE_FRAGMENT_OFFSET_HIGH(length)   ((((length) / 8u) &0x1F00) >> 8)
	Returns the fragment offest high bits.
#define	IP_COMPUTE_FRAGMENT_OFFSET_LOW(length)   (((length) / 8u) &0xFF)
	Returns the fragment offest low bits.
#define	IP_COMPUTE_HEADER_LENGTH(length)   ((uint8_t) ((length) / 4u))
	Returns the IP header length.
#define	IP_FRAGMENT_OFFSET(header)   ((((header)->fragment_offset_high << 8) + (header)->fragment_offset_low) * 8u)
	Returns the fragment offest.
#define	IP_HEADER_CHECKSUM(header)   (htons(ip_checksum((uint8_t *)(header), IP_HEADER_LENGTH(header))))
	Returns the IP packet header checksum.
#define	IP_HEADER_DATA_LENGTH(header)   (IP_TOTAL_LENGTH(header) - IP_HEADER_LENGTH(header))
	Returns the actual IP packet data length.
#define	IP_HEADER_LENGTH(header)   ((header)->header_length * 4u)
	Returns the actual IP header length in bytes.
#define	IP_TOTAL_LENGTH(header)   ntohs((header)->total_length)
	Returns the actual IP packet total length.
IP flags definitions
#define	IPFLAG_FRAGMENT_SHIFT   1
	Fragment flag field shift.
#define	IPFLAG_FRAGMENTED_SHIFT   0
	Fragmented flag field shift.
#define	IPFLAG_DONT_FRAGMENT   (0x1 << IPFLAG_FRAGMENT_SHIFT)
	Don't fragment flag value.
#define	IPFLAG_LAST_FRAGMENT   (0x0 << IPFLAG_FRAGMENTED_SHIFT)
	Last fragment flag value.
#define	IPFLAG_MAY_FRAGMENT   (0x0 << IPFLAG_FRAGMENT_SHIFT)
	May fragment flag value.
#define	IPFLAG_MORE_FRAGMENTS   (0x1 << IPFLAG_FRAGMENTED_SHIFT)
	More fragments flag value.
Typedefs
typedef struct ip_header	ip_header_t
	Type definition of the internet header.
typedef ip_header_t *	ip_header_ref
	Type definition of the internet header pointer.
typedef struct ip_option	ip_option_t
	Type definition of the internet option header.
typedef ip_option_t *	ip_option_ref
	Type definition of the internet option header pointer.
typedef struct ipv4_pseudo_header	ipv4_pseudo_header_t
	Type definition of the internet version 4 pseudo header.
typedef ipv4_pseudo_header_t *	ipv4_pseudo_header_ref
	Type definition of the internet version 4 pseudo header pointer.

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Detailed Description

IP header and options definitions.

Based on the RFC~791.