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    From
    SubjectRe: [OFFTOPIC?] Re: 2.2.x kernels missend odd-sized ICMP pa
    Date
    Followup to:  <199904120151.VAA02001@sleipnir.valparaiso.cl>
    By author: Horst von Brand <vonbrand@sleipnir.valparaiso.cl>
    In newsgroup: linux.dev.kernel
    >
    > BTW, Comer's "Internetworking with TPC/IP, vol 1" tells me that the
    > checksum is computed by ones' complement sum of 16bit quantities in network
    > byte order and stored in network byte order (i.e., big endian), the
    > computation in ping.c:in_cksum is clearly in host format (little endian
    > around here). What gives?
    >

    The reason one's complement (circular carry) is used is because it is
    endian-independent. The littleendian checksum stored in littleendian
    format is the same as the bigendian checksim stored in bigendian
    format.

    -hpa
    --
    "The user's computer downloads the ActiveX code and simulates a 'Blue
    Screen' crash, a generally benign event most users are familiar with
    and that would not necessarily arouse suspicions."
    -- Security exploit description on http://www.zks.net/p3/how.asp

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