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From: Wolfgang Rest (webmaster_at_hackenschmiede.com)
Date: Mon Sep 16 2002 - 07:31:28 CDT

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    sorry for german language

    sshd must have some troubles with md5, when i disable md5 then
    i can login (also with root) when i enable md5 then i get a access denied.

    the harden_suse script is from 7.3

    best regards

    -----Ursprüngliche Nachricht-----
    Von: Philippe Vogel [mailto:filiaapfreenet.de]
    Gesendet: Freitag, 13. September 2002 17:39
    An: Wolfgang Rest
    Betreff: Re: [suse-security] AW: Antwort: AW: Antwort: [suse-security]
    sshd, harden_suse, pam und md5

    1) english mailinglist - see www.suse.de!
    2) harden_suse will work for 7.3, maybe you used the false attributes
    and said everywhere yes!
    3) read the rest

    > ups...
    >
    > sorry.. habe das alte config file mit dem neu erstellen von
    harden_suse
    > verglichen.. und es
    > ist mir nicht aufgefallen...
    >
    > hab nun logischerweise PermitRootLogin = yes

    This is security hole, better allow you user xy and deny root.
    Then switch to root with "su" + password.

    > und mal PAMAuthenticationViaKbdInt = yes

    This is bad!
    Change it to "No"!

    >
    > probiert.. hat aber nichts gebracht.
    > kann es sein das in /etc/pam.d/sshd etwas nicht stimmt?

    The file was O.K. as it was brought to you.
    Maybe harden_suse changed something.
    Was the harden_suse you used written for SuSE 8.0?

    >
    > hier nochmals das nun korrekte sshd_config files:
    >
    > Port 22
    > Protocol 1,2

    I would prefer "Protocol 2" for use of Protocol 2 only.

    > ListenAddress 192.168.2.2

    You have the firewall with internal and external networkcard?
    Then it is a fine thing to have ssh on both cards.
    Therefor you may deactivate this entry.

    > #ListenAddress ::
    > HostKey /etc/ssh/ssh_host_key
    > #HostKey /etc/ssh/ssh_host_rsa_key
    > HostKey /etc/ssh/ssh_host_dsa_key

    You have these keys?
    SSH looks for them and makes authentification with them.
    ssh_host_key -> protocol 1
    ssh_host_rsa_key -> protocol 2
    ssh_host_dsa_key -> protocol 2
    You need this keys been generated for your user to authentificate:
    ssh-keygen -t rsa
    passphrase ...
    ssh-keygen -t dsa
    passphrase ...

    > ServerKeyBits 768
    > LoginGraceTime 300
    > KeyRegenerationInterval 3600

    This is for protocol 1 usage only.

    > PermitRootLogin yes

    Deny it!

    The rest looks normal.
    The harden_suse script does more, it sets kernel cap bits.
    What did you say yes to?
    Rest seems O.K.!

    > #
    > # Don't read ~/.rhosts and ~/.shosts files
    > IgnoreRhosts yes
    > # Uncomment if you don't trust ~/.ssh/known_hosts for
    > RhostsRSAAuthentication
    > #IgnoreUserKnownHosts yes
    > StrictModes yes
    > X11Forwarding no
    > X11DisplayOffset 10
    > PrintMotd yes
    > #PrintLastLog no
    > KeepAlive yes
    >
    > # Logging
    > SyslogFacility AUTH
    > LogLevel INFO
    > #obsoletes QuietMode and FascistLogging
    >
    > RhostsAuthentication no
    > #
    > # For this to work you will also need host keys in
    /etc/ssh/ssh_known_hosts
    > RhostsRSAAuthentication no
    > # similar for protocol version 2
    > HostbasedAuthentication no
    > #
    > RSAAuthentication yes
    >
    > # To disable tunneled clear text passwords, change to no here!
    > PasswordAuthentication yes
    > PermitEmptyPasswords no
    >
    > # Uncomment to disable s/key passwords
    > ChallengeResponseAuthentication no
    >
    > # Uncomment to enable PAM keyboard-interactive authentication
    > # Warning: enabling this may bypass the setting of
    'PasswordAuthentication'
    > #PAMAuthenticationViaKbdInt yes
    >
    > # To change Kerberos options
    > #KerberosAuthentication no
    > #KerberosOrLocalPasswd yes
    > #AFSTokenPassing no
    > #KerberosTicketCleanup no
    >
    > # Kerberos TGT Passing does only work with the AFS kaserver
    > #KerberosTgtPassing yes
    >
    > #CheckMail yes
    > #UseLogin no
    >
    > #MaxStartups 10:30:60
    > #Banner /etc/issue.net
    > #ReverseMappingCheck yes
    >
    > Subsystem sftp /usr/lib/ssh/sftp-server

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