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<refsect1 id="security">
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<title>SECURITY</title>
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This program is set-uid to root, but will switch back to the
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original user and group after bringing up the network interface.
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To use this program for its intended purpose (see <xref
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linkend="purpose"/>), the password for the root file system will
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have to be given out to be stored in a server computer, after
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having been encrypted using an OpenPGP key. This encrypted data
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which will be stored in a server can only be decrypted by the
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OpenPGP key, and the data will only be given out to those
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clients who can prove they actually have that key. This key,
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however, is stored unencrypted on the client side in its initial
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<acronym>RAM</acronym> disk image file system. This is normally
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readable by all, but this is normally fixed during installation
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of this program; file permissions are set so that no-one is able
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The only remaining weak point is that someone with physical
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access to the client hard drive might turn off the client
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computer, read the OpenPGP keys directly from the hard drive,
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and communicate with the server. The defense against this is
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that the server is supposed to notice the client disappearing
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and will stop giving out the encrypted data. Therefore, it is
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important to set the timeout and checker interval values tightly
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on the server. See <citerefentry><refentrytitle
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>mandos</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
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<emphasis>Note</emphasis>: This makes it impossible to have
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<application >Mandos</application> clients which dual-boot to
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another operating system which does <emphasis>not</emphasis> run
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a <application>Mandos</application> client.