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    <title>2004 Reports</title>
    <link>http://eprint.iacr.org/forum/list.php?4</link>
    <description><![CDATA[Discussion forum for Cryptology ePrint Archive reports posted in 2004.
Please put the report number in the subject.

]]></description>
    <language>EN</language>
    <pubDate>Sun, 09 Sep 2012 07:25:58 -0600</pubDate>
    <lastBuildDate>Sun, 09 Sep 2012 07:25:58 -0600</lastBuildDate>
    <category>2004 Reports</category>
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    <ttl>600</ttl>
    <item>
      <title>2004/072/</title>
      <link>http://eprint.iacr.org/forum/read.php?4,884,884#msg-884</link>
      <author>ncourtois</author>
      <description><![CDATA[This paper ignores major historical contributions to the cryptanalysis of HFE, pre-Grobner basis inversion attacks (essentially the same but simpler, there is no fixed ordering of monomials, but the same operations are done). A small correction: 


In 2002 Faugère reported to have broken the HFE Challenge 1 in 96 hours. 

=&gt;

In 2001 Courtois introduces a first inversion attack on HFE and shows that it is frequently much faster than even an impvoed version of the Kipnis-Shamir attack, cf. [Cou01]. These inversion attacks with multivariate algebraic input/output relations are claimed to break HFE in polynomial time if the hidden polynomial degree is an arbitrary fixed value. This paper also outlines a first attack on HFE Challenge 1. Subsequent inversion attacks allow to enhance and optimize this process of solving equations in the ideal of polynomials spanned by the initial equations through GrÄobner bases [FJ03]. In 2002 Faugère reported a first experimental attack on HFE Challenge 1 whcih takes 96 hours which was substantially faster than $2^{60}$-like attack from [Cou01].]]></description>
      <category>2004 Reports</category>
      <guid isPermaLink="true">http://eprint.iacr.org/forum/read.php?4,884,884#msg-884</guid>
      <pubDate>Sun, 09 Sep 2012 07:25:58 -0600</pubDate>
    </item>
    <item>
      <title>Re: md5 collision example</title>
      <link>http://eprint.iacr.org/forum/read.php?4,590,591#msg-591</link>
      <author>russg</author>
      <description><![CDATA[The MD5 collision example is in the wikipedia entry
for MD5, not in 2004/199.

d131dd02c5e6eec4693d9a0698aff95c 2fcab58712467eab4004583eb8fb7f89
55ad340609f4b30283e488832571415a 085125e8f7cdc99fd91dbdf280373c5b
d8823e3156348f5bae6dacd436c919c6 dd53e2b487da03fd02396306d248cda0
e99f33420f577ee8ce54b67080a80d1e c69821bcb6a8839396f9652b6ff72a70

d131dd02c5e6eec4693d9a0698aff95c 2fcab50712467eab4004583eb8fb7f89
55ad340609f4b30283e4888325f1415a 085125e8f7cdc99fd91dbd7280373c5b
d8823e3156348f5bae6dacd436c919c6 dd53e23487da03fd02396306d248cda0
e99f33420f577ee8ce54b67080280d1e c69821bcb6a8839396f965ab6ff72a70]]></description>
      <category>2004 Reports</category>
      <guid isPermaLink="true">http://eprint.iacr.org/forum/read.php?4,590,591#msg-591</guid>
      <pubDate>Sun, 18 Dec 2011 17:24:30 -0700</pubDate>
    </item>
    <item>
      <title>md5 collision example</title>
      <link>http://eprint.iacr.org/forum/read.php?4,590,590#msg-590</link>
      <author>russg</author>
      <description><![CDATA[report 2004/199 has example of MD5 collision.

It also says column 1 is 'offset'.  I tried to verify
the collision with the following hex translated to
ASCII 128 byte files.  I don't understand what the
'offset' is about.  Here's the hex of the two
collisions I translated to 128 byte .bin files.

131dd02c5e6eec4693d9a0698aff95c2fcab50712467eab4004583eb8fb7f8955ad340609f4b30283e4888325f1415a085125e8f7cdc99fd91dbd7280373c5bd8823e3156348f5bae6dacd436c919c6dd53e23487da03fd02396306d248cda0e99f33420f577ee8ce54b67080280d1ec69821bcb6a8839396f965ab6ff72a70

d131dd02c5e6eec4693d9a0698aff95c2fcab58712467eab4004583eb8fb7f8955ad340609f4b30283e488832571415a085125e8f7cdc99fd91dbdf280373c5bd8823e3156348f5bae6dacd436c919c6dd53e2b487da03fd02396306d248cda0e99f33420f577ee8ce54b67080a80d1ec69821bcb6a8839396f9652b6ff72a70

I checked the .bin files and they have the bytes as in the ASCII string.

What am I doing wrong?]]></description>
      <category>2004 Reports</category>
      <guid isPermaLink="true">http://eprint.iacr.org/forum/read.php?4,590,590#msg-590</guid>
      <pubDate>Sat, 17 Dec 2011 16:39:42 -0700</pubDate>
    </item>
    <item>
      <title>2004/057 - entries of the variance-covariance matrix</title>
      <link>http://eprint.iacr.org/forum/read.php?4,575,575#msg-575</link>
      <author>jmclaugh</author>
      <description><![CDATA[Near to the bottom of page 5, this paper states that the vector (\hat{c}_1, ..., \hat{c}_m) will be &quot;distributed around&quot; the vector

((-1)^{z_{1}^{*}}c_1, ..., (-1)^{z_{m}^{*}}c_m)

according to a distribution with a variance-covariance matrix M in which:

* All entries not on the top-left - bottom-right diagonal are zero. (This clearly follows from the assumed independence of the linear approximations)

* All entries M_{ii} on this diagonal are equal to 1/sqrt(N).

Now, the paper has already relied on each t_j having variance \approx N/4. Since

(2t_{j}/N) - 1 = \hat{c}_j

we expect \hat{c}_j to have variance

(2/N)^{2} * (N/4) = 1/N.

Given this, I can't understand why the entries on the diagonal are 1/sqrt(N) and not 1/N. Can someone explain?]]></description>
      <category>2004 Reports</category>
      <guid isPermaLink="true">http://eprint.iacr.org/forum/read.php?4,575,575#msg-575</guid>
      <pubDate>Sun, 06 Nov 2011 12:20:26 -0700</pubDate>
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