diff options
author | des <des@FreeBSD.org> | 2008-08-01 02:48:36 +0000 |
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committer | des <des@FreeBSD.org> | 2008-08-01 02:48:36 +0000 |
commit | b7aa600c416b507a21191efa2689c0a03031d58e (patch) | |
tree | ed813bdf7d8dbee35f19092d185e1a2793885204 /crypto/openssh/ssh.1 | |
parent | a2326b0bec3be2ec01f66d386cfe43139cbc579c (diff) | |
parent | 8f6f5baf400f08937451cf9c8ecc220e9efd2f63 (diff) | |
download | FreeBSD-src-b7aa600c416b507a21191efa2689c0a03031d58e.zip FreeBSD-src-b7aa600c416b507a21191efa2689c0a03031d58e.tar.gz |
Upgrade to OpenSSH 5.1p1.
I have worked hard to reduce diffs against the vendor branch. One
notable change in that respect is that we no longer prefer DSA over
RSA - the reasons for doing so went away years ago. This may cause
some surprises, as ssh will warn about unknown host keys even for
hosts whose keys haven't changed.
MFC after: 6 weeks
Diffstat (limited to 'crypto/openssh/ssh.1')
-rw-r--r-- | crypto/openssh/ssh.1 | 70 |
1 files changed, 62 insertions, 8 deletions
diff --git a/crypto/openssh/ssh.1 b/crypto/openssh/ssh.1 index b04616a..7972f4f 100644 --- a/crypto/openssh/ssh.1 +++ b/crypto/openssh/ssh.1 @@ -34,9 +34,9 @@ .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" -.\" $OpenBSD: ssh.1,v 1.265 2006/10/28 18:08:10 otto Exp $ +.\" $OpenBSD: ssh.1,v 1.277 2008/07/02 13:47:39 djm Exp $ .\" $FreeBSD$ -.Dd September 25, 1999 +.Dd $Mdocdate: July 2 2008 $ .Dt SSH 1 .Os .Sh NAME @@ -44,7 +44,7 @@ .Nd OpenSSH SSH client (remote login program) .Sh SYNOPSIS .Nm ssh -.Op Fl 1246AaCfgkMNnqsTtVvXxY +.Op Fl 1246AaCfgKkMNnqsTtVvXxY .Op Fl b Ar bind_address .Op Fl c Ar cipher_spec .Oo Fl D\ \& @@ -291,6 +291,15 @@ This implies The recommended way to start X11 programs at a remote site is with something like .Ic ssh -f host xterm . +.Pp +If the +.Cm ExitOnForwardFailure +configuration option is set to +.Dq yes , +then a client started with +.Fl f +will wait for all remote port forwards to be successfully established +before placing itself in the background. .It Fl g Allows remote hosts to connect to local forwarded ports. .It Fl I Ar smartcard_device @@ -316,6 +325,9 @@ It is possible to have multiple .Fl i options (and multiple identities specified in configuration files). +.It Fl K +Enables GSSAPI-based authentication and forwarding (delegation) of GSSAPI +credentials to the server. .It Fl k Disables forwarding (delegation) of GSSAPI credentials to the server. .It Fl L Xo @@ -497,6 +509,7 @@ For full details of the options listed below, and their possible values, see .It UserKnownHostsFile .It VerifyHostKeyDNS .It VersionAddendum +.It VisualHostKey .It XAuthLocation .El .It Fl p Ar port @@ -505,7 +518,7 @@ This can be specified on a per-host basis in the configuration file. .It Fl q Quiet mode. -Causes all warning and diagnostic messages to be suppressed. +Causes most warning and diagnostic messages to be suppressed. .It Fl R Xo .Sm off .Oo Ar bind_address : Oc @@ -676,7 +689,7 @@ Both protocols support similar authentication methods, but protocol 2 is preferred since it provides additional mechanisms for confidentiality (the traffic is encrypted using AES, 3DES, Blowfish, CAST128, or Arcfour) -and integrity (hmac-md5, hmac-sha1, hmac-ripemd160). +and integrity (hmac-md5, hmac-sha1, umac-64, hmac-ripemd160). Protocol 1 lacks a strong mechanism for ensuring the integrity of the connection. .Pp @@ -1026,9 +1039,31 @@ Fingerprints can be determined using .Pp .Dl $ ssh-keygen -l -f /etc/ssh/ssh_host_rsa_key .Pp -If the fingerprint is already known, -it can be matched and verified, -and the key can be accepted. +If the fingerprint is already known, it can be matched +and the key can be accepted or rejected. +Because of the difficulty of comparing host keys +just by looking at hex strings, +there is also support to compare host keys visually, +using +.Em random art . +By setting the +.Cm VisualHostKey +option to +.Dq yes , +a small ASCII graphic gets displayed on every login to a server, no matter +if the session itself is interactive or not. +By learning the pattern a known server produces, a user can easily +find out that the host key has changed when a completely different pattern +is displayed. +Because these patterns are not unambiguous however, a pattern that looks +similar to the pattern remembered only gives a good probability that the +host key is the same, not guaranteed proof. +.Pp +To get a listing of the fingerprints along with their random art for +all known hosts, the following command line can be used: +.Pp +.Dl $ ssh-keygen -lv -f ~/.ssh/known_hosts +.Pp If the fingerprint is unknown, an alternative method of verification is available: SSH fingerprints verified by DNS. @@ -1244,6 +1279,13 @@ This file is used in exactly the same way as but allows host-based authentication without permitting login with rlogin/rsh. .Pp +.It ~/.ssh/ +This directory is the default location for all user-specific configuration +and authentication information. +There is no general requirement to keep the entire contents of this directory +secret, but the recommended permissions are read/write/execute for the user, +and not accessible by others. +.Pp .It ~/.ssh/authorized_keys Lists the public keys (RSA/DSA) that can be used for logging in as this user. The format of this file is described in the @@ -1420,6 +1462,18 @@ manual page for more information. .%T "Diffie-Hellman Group Exchange for the Secure Shell (SSH) Transport Layer Protocol" .%D 2006 .Re +.Rs +.%R RFC 4716 +.%T "The Secure Shell (SSH) Public Key File Format" +.%D 2006 +.Re +.Rs +.%T "Hash Visualization: a New Technique to improve Real-World Security" +.%A A. Perrig +.%A D. Song +.%D 1999 +.%O "International Workshop on Cryptographic Techniques and E-Commerce (CrypTEC '99)" +.Re .Sh AUTHORS OpenSSH is a derivative of the original and free ssh 1.2.12 release by Tatu Ylonen. |