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libnet

===============================================================================
    $Id: RAWSOCKET_NON_SEQUITUR,v 1.1.1.1 2012/02/21 22:14:23 misho Exp $
    LIBNET 1.1 (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.com>
                               http://www.packetfactory.net/libnet
===============================================================================

    Raw sockets are horribly non-standard across implementations.  Here is
    an incomplete list of some of the differences (corrections welcomed):

    Linux 2.2+:

    IP fragmentation:       performed if packet is larger than MTU
    IP checksum:            always filled in
    IP total length:        always filled in
    IP ID:                  filled in when zero
    IP source address:      filled in when zero
    IP destination address: filled in when zero
    Max packet size before kernel complains: 1500 bytes

    Solaris 2.6+:

    IP fragmentation bits:  can't specify 
    IP fragmentation:       performed if packet is larger than MTU
    IP DF bit:              always set
    IP checksum:            always filled in
    Max packet size before kernel complains: ?

    OpenBSD 2.8+:

    IP fragmentation:       performed if packet is larger than MTU
    Max packet size before kernel complains: 8192 bytes

  Solaris,
    for example, has terrible support for this packet interface.  Older OpenBSD
    versions and recent FreeBSD versions have the BSD_BYTE_SWAP issue where
    the ip_len and ip_frag fields need to be in little endian order.  Linux
    apparently doesn't allow for the injection of broadcast IP datagrams.
    Whenever complete control over the IP header is desired, use the link
    layer API.

EOF