ipv4_hdr Struct Reference

The IPv4 header. More...

#include <ipv4.h>

Data Fields
uint8_t	ihl:4
uint8_t	version:4
union {
uint8_t   tos
uint8_t   dscp_ecn
struct {
uint8_t   ecn:2
uint8_t   dscp:6
}
};
uint16_t	tot_len
uint16_t	id
union {
uint16_t   frag_off
struct {
uint8_t   frag_off1:5
uint8_t   mf:1
uint8_t   df:1
uint8_t   reserved:1
uint8_t   frag_off2
}
};
uint8_t	ttl
uint8_t	protocol
uint16_t	check
uint32_t	saddr
uint32_t	daddr
uint8_t	options [0]

Detailed Description

The IPv4 header.

Field Documentation

union { ... }

union { ... }

uint16_t ipv4_hdr::check

The checksum over the IP header

uint32_t ipv4_hdr::daddr

The destination IP address

uint8_t ipv4_hdr::df

uint8_t ipv4_hdr::dscp

uint8_t ipv4_hdr::dscp_ecn

The combined DSCP and ECN fields

uint8_t ipv4_hdr::ecn

uint16_t ipv4_hdr::frag_off

The IP flags + Fragment Offset in 64-bit words

uint8_t ipv4_hdr::frag_off1

uint8_t ipv4_hdr::frag_off2

The Fragment Offset in 64-bit words (part 2)

uint16_t ipv4_hdr::id

The IDentification of the packet

uint8_t ipv4_hdr::ihl

uint8_t ipv4_hdr::mf

uint8_t ipv4_hdr::options[0]

The IP options start here

uint8_t ipv4_hdr::protocol

The Protocol of the next header

uint8_t ipv4_hdr::reserved

uint32_t ipv4_hdr::saddr

The source IP address

uint8_t ipv4_hdr::tos

The Type Of Service (TOS)

uint16_t ipv4_hdr::tot_len

The Total Length (header + payload)

uint8_t ipv4_hdr::ttl

The Time To Live (TTL)

uint8_t ipv4_hdr::version

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

• ipv4.h