From 6f2d6f78cd11231d6f7ffd6361812b1bd49a4c34 Mon Sep 17 00:00:00 2001 From: Daniel Kahn Gillmor Date: Thu, 12 Jun 2008 17:25:55 -0400 Subject: Major openpgp2ssh overhaul. It's an unforgiving and brittle tool, but it should do what we expect it to do, and its major limitations should be documented in the man page. --- man/man1/openpgp2ssh.1 | 47 +++++++++++++++++++++++++++++++---------------- 1 file changed, 31 insertions(+), 16 deletions(-) (limited to 'man/man1') diff --git a/man/man1/openpgp2ssh.1 b/man/man1/openpgp2ssh.1 index 6267141..1a02b38 100644 --- a/man/man1/openpgp2ssh.1 +++ b/man/man1/openpgp2ssh.1 @@ -12,16 +12,16 @@ openpgp2ssh .Nm gpg --export-secret-key $KEYID | openpgp2ssh $KEYID .Sh DESCRIPTION -openpgp2ssh takes OpenPGP-formatted RSA and DSA keys on standard -input, and spits out the requested equivalent SSH-style key on -standard output. +openpgp2ssh takes an OpenPGP-formatted primary key and associated +subkeys on standard input, and spits out the requested equivalent +SSH-style key on standard output. -If the data on standard input contains only a single key, you can -invoke openpgp2ssh without arguments. If the data on standard input -contains multiple keys (e.g. a primary key and associated subkeys), -you must specify a specific OpenPGP keyid (e.g. CCD2ED94D21739E9) or +If the data on standard input contains no subkeys, you can invoke +openpgp2ssh without arguments. If the data on standard input contains +multiple keys (e.g. a primary key and associated subkeys), you must +specify a specific OpenPGP keyid (e.g. CCD2ED94D21739E9) or fingerprint as the first argument to indicate which key to export. -The keyid must be at least 8 hex characters. +The keyid must be exactly 16 hex characters. If the input contains an OpenPGP RSA or DSA public key, it will be converted to the OpenSSH-style single-line keystring, prefixed with @@ -31,20 +31,29 @@ insertion into known_hosts files and authorized_keys files. If the input contains an OpenPGP RSA or DSA secret key, it will be converted to the equivalent PEM-encoded private key. -Note that the keys produced by this process are stripped of all -identifying information, including certifications, self-signatures, -etc. - openpgp2ssh is part of the .Xr monkeysphere 1 framework for providing a PKI for SSH. +.Sh CAVEATS +The keys produced by this process are stripped of all identifying +information, including certifications, self-signatures, etc. This is +intentional, since ssh attaches no inherent significance to these +features. + +openpgp2ssh only works with RSA or DSA keys, because those are the +only ones which work with ssh. + +Assuming a valid key type, though, openpgp2ssh will produce output for +any requested key. This means, among other things, that it will +happily export revoked keys, unverifiable keys, expired keys, etc. +Make sure you do your own key validation before using this tool! .Sh EXAMPLES .Nm gpg --export-secret-key $KEYID | openpgp2ssh $KEYID | ssh-add -c /dev/stdin This pushes the secret key into the active .Xr ssh-agent 1 . -Tools (such as -.Xr ssh 1 ) +Tools such as +.Xr ssh 1 which know how to talk to the .Xr ssh-agent 1 can now rely on the key. @@ -58,8 +67,14 @@ lsh(1) and putty(1). Secret key output is currently not passphrase-protected. -This program is not yet implemented, and this man page currently only -describes expected functionality. +openpgp2ssh currently cannot handle passphrase-protected secret keys on input. + +It would be nice to be able to use keyids shorter or longer than 16 +hex characters. + +openpgp2ssh only acts on keys associated with the first primary key +passed in. If you send it more than one primary key, it will silently +ignore later ones. .Sh SEE ALSO .Xr monkeysphere 1 , .Xr ssh 1 , -- cgit v1.2.3