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NetBurner 3.5.6
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NetBurner 3.5.6
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IP Header Structure (IPv4) More...
#include <ip.h>
Public Attributes | |
| uint8_t | versionNLength |
| Version (4 bits) and header length (4 bits). Version=4 for IPv4, length in 32-bit words IPPKT::bVerHdrLen. | |
| uint8_t | diffServNEcn |
| Differentiated Services Code Point (6 bits) and Explicit Congestion Notification (2 bits) - used for QoS IPPKT::bTos. | |
| beuint16_t | totalLength |
| Total datagram size in bytes including IP header and data payload IPPKT::wLength. | |
| beuint16_t | identification |
| Fragment identification field - same for all fragments of a datagram IPPKT::wpktId. | |
| beuint16_t | flagsNFragmentOffset |
| Flags (3 bits) and fragment offset (13 bits) - offset in 8-byte units IPPKT::wFlags_Frag. | |
| uint8_t | timeToLive |
| Time To Live - typically used as hop count, decremented by each router IPPKT::bTTL. | |
| uint8_t | protocol |
| IANA protocol number identifying next-level protocol (TCP=6, UDP=17, ICMP=1) IPPKT::proto. | |
| beuint16_t | headerChecksum |
| Header checksum - 16-bit one's complement checksum of IP header only (not data) IPPKT::hCSum. | |
| beuint32_t | sourceAddress |
| Source IP address as 4 octets in network byte order IPPKT::ipSrc. | |
| beuint32_t | destinationAddress |
| Destination IP address as 4 octets in network byte order IPPKT::ipDst. | |
IP Header Structure (IPv4)
Standard IPv4 packet header as defined in IETF RFC 791 (September 1981) and MIL-STD-1777. This structure represents the 20-byte minimum IP header. IP options, if present, follow this structure and are indicated by a header length value greater than 5.
All multi-byte fields are in network byte order (big-endian) and use the beuint types for automatic endianness handling.