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

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

SYNOPSIS
     ssh-add [-cDdKkLlqvXx] [-E	fingerprint_hash] [-H hostkey_file]
	     [-h destination_constraint] [-S provider] [-t life] [file ...]
     ssh-add -s	pkcs11
     ssh-add -e	pkcs11
     ssh-add -T	pubkey ...

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_ecdsa, ~/.ssh/id_ecdsa_sk, ~/.ssh/id_ed25519,
     ~/.ssh/id_ed25519_sk, and ~/.ssh/id_dsa.  After loading a private key,
     ssh-add will try to load corresponding certificate	information from the
     filename obtained by appending -cert.pub to the name of the private key
     file.  Alternative	file names can be given	on the command 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 environ-
     ment 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	ssh-askpass(1).	 Successful confirmation is signaled by	a zero
	     exit status from ssh-askpass(1), 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 de-
	     fault identities and their	corresponding certificates will	be re-
	     moved.  Otherwise,	the argument list will be interpreted as a
	     list of paths to public key files to specify keys and certifi-
	     cates to be removed from the agent.  If no	public key is found at
	     a given path, ssh-add will	append .pub and	retry.	If the argu-
	     ment list consists	of "-" then ssh-add will read public keys to
	     be	removed	from standard input.

     -E	fingerprint_hash
	     Specifies the hash	algorithm used when displaying key finger-
	     prints.  Valid options are: "md5" and "sha256".  The default is
	     "sha256".

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

     -H	hostkey_file
	     Specifies a known hosts file to look up hostkeys when using des-
	     tination-constrained keys via the -h flag.	 This option may be
	     specified multiple	times to allow multiple	files to be searched.
	     If	no files are specified,	ssh-add	will use the default
	     ssh_config(5) known hosts files: ~/.ssh/known_hosts,
	     ~/.ssh/known_hosts2, /etc/ssh/ssh_known_hosts, and
	     /etc/ssh/ssh_known_hosts2.

     -h	destination_constraint
	     When adding keys, constrain them to be usable only	through	spe-
	     cific hosts or to specific	destinations.

	     Destination constraints of	the form `[user@]dest-hostname'	permit
	     use of the	key only from the origin host (the one running
	     ssh-agent(1)) to the listed destination host, with	optional user
	     name.

	     Constraints of the	form `src-hostname>[user@]dst-hostname'	allow
	     a key available on	a forwarded ssh-agent(1) to be used through a
	     particular	host (as specified by `src-hostname') to authenticate
	     to	a further host,	specified by `dst-hostname'.

	     Multiple destination constraints may be added when	loading	keys.
	     When attempting authentication with a key that has	destination
	     constraints, the whole connection path, including ssh-agent(1)
	     forwarding, is tested against those constraints and each hop must
	     be	permitted for the attempt to succeed.  For example, if key is
	     forwarded to a remote host, `host-b', and is attempting authenti-
	     cation to another host, `host-c', then the	operation will be suc-
	     cessful only if `host-b' was permitted from the origin host and
	     the subsequent `host-b>host-c' hop	is also	permitted by destina-
	     tion constraints.

	     Hosts are identified by their host	keys, and are looked up	from
	     known hosts files by ssh-add.  Wildcards patterns may be used for
	     hostnames and certificate host keys are supported.	 By default,
	     keys added	by ssh-add are not destination constrained.

	     Destination constraints were added	in OpenSSH release 8.9.	 Sup-
	     port in both the remote SSH client	and server is required when
	     using destination-constrained keys	over a forwarded ssh-agent(1)
	     channel.

	     It	is also	important to note that destination constraints can
	     only be enforced by ssh-agent(1) when a key is used, or when it
	     is	forwarded by a cooperating ssh(1).  Specifically, it does not
	     prevent an	attacker with access to	a remote SSH_AUTH_SOCK from
	     forwarding	it again and using it on a different host (but only to
	     a permitted destination).

     -K	     Load resident keys	from a FIDO authenticator.

     -k	     When loading keys into or deleting	keys from the agent, process
	     plain private keys	only and skip certificates.

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

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

     -q	     Be	quiet after a successful operation.

     -S	provider
	     Specifies a path to a library that	will be	used when adding FIDO
	     authenticator-hosted keys,	overriding the default of using	the
	     internal USB HID support.

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

     -T	pubkey ...
	     Tests whether the private keys that correspond to the specified
	     pubkey files are usable by	performing sign	and verify operations
	     on	each.

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

     -v	     Verbose mode.  Causes ssh-add to print debugging messages about
	     its progress.  This is helpful in debugging problems.  Multiple
	     -v	options	increase the verbosity.	 The maximum is	3.

     -X	     Unlock the	agent.

     -x	     Lock the agent with a password.

ENVIRONMENT
     DISPLAY, SSH_ASKPASS and SSH_ASKPASS_REQUIRE
	     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 (by default "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.

	     SSH_ASKPASS_REQUIRE allows	further	control	over the use of	an
	     askpass program.  If this variable	is set to "never" then ssh-add
	     will never	attempt	to use one.  If	it is set to "prefer", then
	     ssh-add will prefer to use	the askpass program instead of the TTY
	     when requesting passwords.	 Finally, if the variable is set to
	     "force", then the askpass program will be used for	all passphrase
	     input regardless of whether DISPLAY is set.

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

     SSH_SK_PROVIDER
	     Specifies a path to a library that	will be	used when loading any
	     FIDO authenticator-hosted keys, overriding	the default of using
	     the built-in USB HID support.

FILES
     ~/.ssh/id_dsa
     ~/.ssh/id_ecdsa
     ~/.ssh/id_ecdsa_sk
     ~/.ssh/id_ed25519
     ~/.ssh/id_ed25519_sk
     ~/.ssh/id_rsa
	     Contains the DSA, ECDSA, authenticator-hosted ECDSA, Ed25519, au-
	     thenticator-hosted	Ed25519	or 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-askpass(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 cre-
     ated OpenSSH.  Markus Friedl contributed the support for SSH protocol
     versions 1.5 and 2.0.

FreeBSD	13.0		       February	4, 2022			  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | ENVIRONMENT | FILES | EXIT STATUS | SEE ALSO | AUTHORS

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