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Full Discussion: Controlling a child's stdin/stdout (not working with scp)
Top Forums Programming Controlling a child's stdin/stdout (not working with scp) Post 302402835 by Corona688 on Wednesday 10th of March 2010 07:01:43 PM
Old 03-10-2010
Yes, it does, and no, it won't let you, and that's for a reason -- stored passwords are not only inherently dangerous but completely unnecessary. Use shared keys, that's what they're there for. There's instructions for them plastered all over the internet and you can use them in ways that obey the spirit and letter of that rule -- give the shared key a password and use ssh-agent. That way you need to type the password once, to get the key, after which you can use the key to login automatically until your ssh-agent session finishes.
 

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LEARN ABOUT NETBSD

ssh-add

SSH-ADD(1)						    BSD General Commands Manual 						SSH-ADD(1)

NAME

     ssh-add -- adds private key identities to the authentication agent

SYNOPSIS

     ssh-add [-cDdLlXx] [-t life] [file ...]
     ssh-add -s pkcs11
     ssh-add -e pkcs11

DESCRIPTION

     ssh-add adds private key identities to the authentication agent, ssh-agent(1).  When run without arguments, it adds the files ~/.ssh/id_rsa,
     ~/.ssh/id_dsa, ~/.ssh/id_ecdsa and ~/.ssh/identity.  After loading a private key, ssh-add will try to load corresponding certificate informa-
     tion from the filename obtained by appending -cert.pub to the name of the private key file.  Alternative file names can be given on the com-
     mand line.

     If any file requires a passphrase, ssh-add asks for the passphrase from the user.	The passphrase is read from the user's tty.  ssh-add
     retries the last passphrase if multiple identity files are given.

     The authentication agent must be running and the SSH_AUTH_SOCK environment variable must contain the name of its socket for ssh-add to work.

     The options are as follows:

     -c      Indicates that added identities should be subject to confirmation before being used for authentication.  Confirmation is performed by
	     the SSH_ASKPASS program mentioned below.  Successful confirmation is signaled by a zero exit status from the SSH_ASKPASS program,
	     rather than text entered into the requester.

     -D      Deletes all identities from the agent.

     -d      Instead of adding identities, removes identities from the agent.  If ssh-add has been run without arguments, the keys for the default
	     identities will be removed.  Otherwise, the argument list will be interpreted as a list of paths to public key files and matching
	     keys will be removed from the agent.  If no public key is found at a given path, ssh-add will append .pub and retry.

     -e pkcs11
	     Remove keys provided by the PKCS#11 shared library pkcs11.

     -L      Lists public key parameters of all identities currently represented by the agent.

     -l      Lists fingerprints of all identities currently represented by the agent.

     -s pkcs11
	     Add keys provided by the PKCS#11 shared library pkcs11.

     -t life
	     Set a maximum lifetime when adding identities to an agent.  The lifetime may be specified in seconds or in a time format specified in
	     sshd_config(5).

     -X      Unlock the agent.

     -x      Lock the agent with a password.

ENVIRONMENT

     DISPLAY and SSH_ASKPASS
	     If ssh-add needs a passphrase, it will read the passphrase from the current terminal if it was run from a terminal.  If ssh-add does
	     not have a terminal associated with it but DISPLAY and SSH_ASKPASS are set, it will execute the program specified by SSH_ASKPASS and
	     open an X11 window to read the passphrase.  This is particularly useful when calling ssh-add from a .xsession or related script.
	     (Note that on some machines it may be necessary to redirect the input from /dev/null to make this work.)

     SSH_AUTH_SOCK
	     Identifies the path of a UNIX-domain socket used to communicate with the agent.

FILES

     ~/.ssh/identity
	     Contains the protocol version 1 RSA authentication identity of the user.

     ~/.ssh/id_dsa
	     Contains the protocol version 2 DSA authentication identity of the user.

     ~/.ssh/id_ecdsa
	     Contains the protocol version 2 ECDSA authentication identity of the user.

     ~/.ssh/id_rsa
	     Contains the protocol version 2 RSA authentication identity of the user.

     Identity files should not be readable by anyone but the user.  Note that ssh-add ignores identity files if they are accessible by others.

EXIT STATUS

     Exit status is 0 on success, 1 if the specified command fails, and 2 if ssh-add is unable to contact the authentication agent.

SEE ALSO

     ssh(1), ssh-agent(1), ssh-keygen(1), sshd(8)

AUTHORS

     OpenSSH is a derivative of the original and free ssh 1.2.12 release by Tatu Ylonen.  Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos,
     Theo de Raadt and Dug Song removed many bugs, re-added newer features and created OpenSSH.  Markus Friedl contributed the support for SSH
     protocol versions 1.5 and 2.0.

BSD
								 October 28, 2010							       BSD
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