diff options
author | Damien Miller <djm@cvs.openbsd.org> | 2013-12-07 08:08:27 +0000 |
---|---|---|
committer | Damien Miller <djm@cvs.openbsd.org> | 2013-12-07 08:08:27 +0000 |
commit | a3fc916bb6b435cb2c7e7ba545e6ad3e304d9052 (patch) | |
tree | 67de119c45da69a5833ed316976434580323d45d /usr.bin | |
parent | 22470cbb72639e25878645fe5c1f85b7ec9db378 (diff) |
document -a and -o wrt new key format
Diffstat (limited to 'usr.bin')
-rw-r--r-- | usr.bin/ssh/ssh-keygen.1 | 31 |
1 files changed, 24 insertions, 7 deletions
diff --git a/usr.bin/ssh/ssh-keygen.1 b/usr.bin/ssh/ssh-keygen.1 index 0d55854e93d..689db22ff25 100644 --- a/usr.bin/ssh/ssh-keygen.1 +++ b/usr.bin/ssh/ssh-keygen.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: ssh-keygen.1,v 1.116 2013/06/27 14:05:37 jmc Exp $ +.\" $OpenBSD: ssh-keygen.1,v 1.117 2013/12/07 08:08:26 djm Exp $ .\" .\" Author: Tatu Ylonen <ylo@cs.hut.fi> .\" Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland @@ -35,7 +35,7 @@ .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" -.Dd $Mdocdate: June 27 2013 $ +.Dd $Mdocdate: December 7 2013 $ .Dt SSH-KEYGEN 1 .Os .Sh NAME @@ -103,7 +103,7 @@ .Fl T Ar output_file .Fl f Ar input_file .Op Fl v -.Op Fl a Ar num_trials +.Op Fl a Ar rounds .Op Fl J Ar num_lines .Op Fl j Ar start_line .Op Fl K Ar checkpt @@ -222,11 +222,20 @@ an empty passphrase, default bits for the key type, and default comment. This is used by .Pa /etc/rc to generate new host keys. -.It Fl a Ar trials -Specifies the number of primality tests to perform when screening DH-GEX -candidates using the +.It Fl a Ar rounds +When saving a new-format private key (i.e. an ed25519 key or any SSH protocol +2 key when the +.Fl o +flag is set), this option specifies the number of KDF (key derivation function) +rounds used. +Higher numbers result in slower passphrase verification and increased +resistance to brute-force password cracking (should the keys be stolen). +.Pp +When screening DH-GEX candidates ( +using the .Fl T -command. +command). +This option specifies the number of primality tests to perform. .It Fl B Show the bubblebabble digest of specified private or public key file. .It Fl b Ar bits @@ -447,6 +456,14 @@ format. .El .Pp At present, no options are valid for host keys. +.It Fl o +Causes +.Nm +to save SSH protocol 2 private keys using the new OpenSSH format rather than +the more compatible PEM format. +The new format has increased resistance to brute-force password cracking +but is not supported by versions of OpenSSH prior to 6.5. +Ed25519 keys always use the new private key format. .It Fl P Ar passphrase Provides the (old) passphrase. .It Fl p |