Easiest way to start SSH without password request, and using the pwd stored in $HOME

frenchn00b · 05-27-2009, 11:43 PM

What would be the easiest way to start SSH without password request, and using the pwd stored in $HOME
Regards

jschiwal · 05-27-2009, 11:57 PM

If the server is configured to use public key authentication, you only need to enter the passphrase (at the client) once a session if you use ssh-agent.

example:
eval $(ssh-agent)
ssh-add

Alternatively, look for the .xsession file your client uses then you start up.
e.g. on SuSE,
/etc/X11/xdm/sys.xsession

Look for this line. Now you just have to enter the passphrase once.
# If ssh is configured and ssh-agent is wanted set "yes"
usessh=yes

You can also have a private key without a passphrase, but that would put the server at risk if the client is stolen, or compromised. Something similar is what happened at Red Hat.

frenchn00b · 05-28-2009, 04:37 AM

Quote:

Originally Posted by jschiwal

If the server is configured to use public key authentication, you only need to enter the passphrase (at the client) once a session if you use ssh-agent.

example:
eval $(ssh-agent)
ssh-add

Alternatively, look for the .xsession file your client uses then you start up.
e.g. on SuSE,
/etc/X11/xdm/sys.xsession

Look for this line. Now you just have to enter the passphrase once.
# If ssh is configured and ssh-agent is wanted set "yes"
usessh=yes

You can also have a private key without a passphrase, but that would put the server at risk if the client is stolen, or compromised. Something similar is what happened at Red Hat.

here it my ssh config :
I try to keep it cuz I know it is secured.

Quote:

# Package generated configuration file
# See the sshd(8) manpage for details

# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes

# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768

# Logging
SyslogFacility AUTH
LogLevel INFO

# Authentication:
LoginGraceTime 120
PermitRootLogin no
StrictModes yes

RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys

# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
#IgnoreUserKnownHosts yes

# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no

# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no

# Change to no to disable tunnelled clear text passwords
#PasswordAuthentication yes

# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no

#MaxStartups 10:30:60
#Banner /etc/issue.net

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

Subsystem sftp /usr/lib/openssh/sftp-server

UsePAM yes

frenchn00b · 09-13-2009, 04:13 PM

Hello

I followed this howto, but the security is only based on DNS, thtat's all.

I would like to not to base it on DNS but only on teh mac address
https://help.ubuntu.com/community/Samba/Kerberos

is that possible?

would you have any configuration that u are using and working.?
thanks you

lutusp · 09-13-2009, 09:28 PM

Quote:

Originally Posted by frenchn00b

Hello

I followed this howto, but the security is only based on DNS, thtat's all.

I would like to not to base it on DNS but only on teh mac address
https://help.ubuntu.com/community/Samba/Kerberos

is that possible?

On a LAN, yes. On the Internet, no. Macs don't normally propagate very far. But the present key exchange method is quite robust and secure (and will remain so until they perfect the quantum computer).

Basing security on Macs is not really secure anyway -- one can temporarily assign any arbitrary Mac to a NIC for various purposes.

Quote:

... the security is only based on DNS, thtat's all

What you say here isn't actually true -- if you have distributed authorization keys to all the communicating computers, and if they are physically secure, than the security isn't based on DNS any more.