1 files changed, 42 insertions, 15 deletions

diff --git a/ssh-keygen.1 b/ssh-keygen.1
index 151cab0ef..299ccf8dd 100644
--- a/ssh-keygen.1
+++ b/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 1.119 2013/12/21 07:10:47 tedu 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 21 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
@@ -139,8 +139,8 @@
 generates, manages and converts authentication keys for
 .Xr ssh 1 .
 .Nm
-can create RSA keys for use by SSH protocol version 1 and DSA, ECDSA or RSA
-keys for use by SSH protocol version 2.
+can create RSA keys for use by SSH protocol version 1 and
+DSA, ECDSA, ED25519 or RSA keys for use by SSH protocol version 2.
 The type of key to be generated is specified with the
 .Fl t
 option.
@@ -167,8 +167,9 @@ Normally each user wishing to use SSH
 with public key authentication runs this once to create the authentication
 key in
 .Pa ~/.ssh/identity ,
+.Pa ~/.ssh/id_dsa ,
 .Pa ~/.ssh/id_ecdsa ,
-.Pa ~/.ssh/id_dsa
+.Pa ~/.ssh/id_ed25519
 or
 .Pa ~/.ssh/id_rsa .
 Additionally, the system administrator may use this to generate host keys.
@@ -214,15 +215,25 @@ should be placed to be activated.
 The options are as follows:
 .Bl -tag -width Ds
 .It Fl A
-For each of the key types (rsa1, rsa, dsa and ecdsa) for which host keys
+For each of the key types (rsa1, rsa, dsa, ecdsa and ed25519)
+for which host keys
 do not exist, generate the host keys with the default key file path,
 an empty passphrase, default bits for the key type, and default comment.
 This is used by system administration scripts 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
@@ -236,6 +247,9 @@ flag determines the key length by selecting from one of three elliptic
 curve sizes: 256, 384 or 521 bits.
 Attempting to use bit lengths other than these three values for ECDSA keys
 will fail.
+ED25519 keys have a fixed length and the
+.Fl b
+flag will be ignored.
 .It Fl C Ar comment
 Provides a new comment.
 .It Fl c
@@ -443,6 +457,14 @@ 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
@@ -494,7 +516,8 @@ The possible values are
 .Dq rsa1
 for protocol version 1 and
 .Dq dsa ,
-.Dq ecdsa
+.Dq ecdsa ,
+.Dq ed25519 ,
 or
 .Dq rsa
 for protocol version 2.
@@ -687,7 +710,7 @@ Please refer to those manual pages for details.
 .Nm
 is able to manage OpenSSH format Key Revocation Lists (KRLs).
 These binary files specify keys or certificates to be revoked using a
-compact format, taking as little a one bit per certificate if they are being
+compact format, taking as little as one bit per certificate if they are being
 revoked by serial number.
 .Pp
 KRLs may be generated using the
@@ -774,8 +797,10 @@ There is no need to keep the contents of this file secret.
 .Pp
 .It Pa ~/.ssh/id_dsa
 .It Pa ~/.ssh/id_ecdsa
+.It Pa ~/.ssh/id_ed25519
 .It Pa ~/.ssh/id_rsa
-Contains the protocol version 2 DSA, ECDSA or RSA authentication identity of the user.
+Contains the protocol version 2 DSA, ECDSA, ED25519 or RSA
+authentication identity of the user.
 This file should not be readable by anyone but the user.
 It is possible to
 specify a passphrase when generating the key; that passphrase will be
@@ -788,8 +813,10 @@ will read this file when a login attempt is made.
 .Pp
 .It Pa ~/.ssh/id_dsa.pub
 .It Pa ~/.ssh/id_ecdsa.pub
+.It Pa ~/.ssh/id_ed25519.pub
 .It Pa ~/.ssh/id_rsa.pub
-Contains the protocol version 2 DSA, ECDSA or RSA public key for authentication.
+Contains the protocol version 2 DSA, ECDSA, ED25519 or RSA
+public key for authentication.
 The contents of this file should be added to
 .Pa ~/.ssh/authorized_keys
 on all machines