diff options
Diffstat (limited to 'ssh.1')
-rw-r--r-- | ssh.1 | 69 |
1 files changed, 48 insertions, 21 deletions
@@ -34,8 +34,8 @@ | |||
34 | .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | 34 | .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
35 | .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | 35 | .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
36 | .\" | 36 | .\" |
37 | .\" $OpenBSD: ssh.1,v 1.283 2009/03/19 15:15:09 jmc Exp $ | 37 | .\" $OpenBSD: ssh.1,v 1.302 2010/03/05 10:28:21 djm Exp $ |
38 | .Dd $Mdocdate: March 19 2009 $ | 38 | .Dd $Mdocdate: March 5 2010 $ |
39 | .Dt SSH 1 | 39 | .Dt SSH 1 |
40 | .Os | 40 | .Os |
41 | .Sh NAME | 41 | .Sh NAME |
@@ -54,6 +54,7 @@ | |||
54 | .Oc | 54 | .Oc |
55 | .Op Fl e Ar escape_char | 55 | .Op Fl e Ar escape_char |
56 | .Op Fl F Ar configfile | 56 | .Op Fl F Ar configfile |
57 | .Op Fl I Ar pkcs11 | ||
57 | .Bk -words | 58 | .Bk -words |
58 | .Op Fl i Ar identity_file | 59 | .Op Fl i Ar identity_file |
59 | .Ek | 60 | .Ek |
@@ -77,12 +78,11 @@ | |||
77 | .Sm on | 78 | .Sm on |
78 | .Oc | 79 | .Oc |
79 | .Op Fl S Ar ctl_path | 80 | .Op Fl S Ar ctl_path |
80 | .Bk -words | 81 | .Op Fl W Ar host : Ns Ar port |
81 | .Oo Fl w Ar local_tun Ns | 82 | .Oo Fl w Ar local_tun Ns |
82 | .Op : Ns Ar remote_tun Oc | 83 | .Op : Ns Ar remote_tun Oc |
83 | .Oo Ar user Ns @ Oc Ns Ar hostname | 84 | .Oo Ar user Ns @ Oc Ns Ar hostname |
84 | .Op Ar command | 85 | .Op Ar command |
85 | .Ek | ||
86 | .Sh DESCRIPTION | 86 | .Sh DESCRIPTION |
87 | .Nm | 87 | .Nm |
88 | (SSH client) is a program for logging into a remote machine and for | 88 | (SSH client) is a program for logging into a remote machine and for |
@@ -132,8 +132,9 @@ This can also be specified on a per-host basis in a configuration file. | |||
132 | .Pp | 132 | .Pp |
133 | Agent forwarding should be enabled with caution. | 133 | Agent forwarding should be enabled with caution. |
134 | Users with the ability to bypass file permissions on the remote host | 134 | Users with the ability to bypass file permissions on the remote host |
135 | (for the agent's Unix-domain socket) | 135 | (for the agent's |
136 | can access the local agent through the forwarded connection. | 136 | .Ux Ns -domain |
137 | socket) can access the local agent through the forwarded connection. | ||
137 | An attacker cannot obtain key material from the agent, | 138 | An attacker cannot obtain key material from the agent, |
138 | however they can perform operations on the keys that enable them to | 139 | however they can perform operations on the keys that enable them to |
139 | authenticate using the identities loaded into the agent. | 140 | authenticate using the identities loaded into the agent. |
@@ -284,13 +285,11 @@ will wait for all remote port forwards to be successfully established | |||
284 | before placing itself in the background. | 285 | before placing itself in the background. |
285 | .It Fl g | 286 | .It Fl g |
286 | Allows remote hosts to connect to local forwarded ports. | 287 | Allows remote hosts to connect to local forwarded ports. |
287 | .It Fl I Ar smartcard_device | 288 | .It Fl I Ar pkcs11 |
288 | Specify the device | 289 | Specify the PKCS#11 shared library |
289 | .Nm | 290 | .Nm |
290 | should use to communicate with a smartcard used for storing the user's | 291 | should use to communicate with a PKCS#11 token providing the user's |
291 | private RSA key. | 292 | private RSA key. |
292 | This option is only available if support for smartcard devices | ||
293 | is compiled in (default is no support). | ||
294 | .It Fl i Ar identity_file | 293 | .It Fl i Ar identity_file |
295 | Selects a file from which the identity (private key) for | 294 | Selects a file from which the identity (private key) for |
296 | RSA or DSA authentication is read. | 295 | RSA or DSA authentication is read. |
@@ -307,6 +306,11 @@ It is possible to have multiple | |||
307 | .Fl i | 306 | .Fl i |
308 | options (and multiple identities specified in | 307 | options (and multiple identities specified in |
309 | configuration files). | 308 | configuration files). |
309 | .Nm | ||
310 | will also try to load certificate information from the filename obtained | ||
311 | by appending | ||
312 | .Pa -cert.pub | ||
313 | to identity filenames. | ||
310 | .It Fl K | 314 | .It Fl K |
311 | Enables GSSAPI-based authentication and forwarding (delegation) of GSSAPI | 315 | Enables GSSAPI-based authentication and forwarding (delegation) of GSSAPI |
312 | credentials to the server. | 316 | credentials to the server. |
@@ -469,6 +473,7 @@ For full details of the options listed below, and their possible values, see | |||
469 | .It NumberOfPasswordPrompts | 473 | .It NumberOfPasswordPrompts |
470 | .It PasswordAuthentication | 474 | .It PasswordAuthentication |
471 | .It PermitLocalCommand | 475 | .It PermitLocalCommand |
476 | .It PKCS11Provider | ||
472 | .It Port | 477 | .It Port |
473 | .It PreferredAuthentications | 478 | .It PreferredAuthentications |
474 | .It Protocol | 479 | .It Protocol |
@@ -481,7 +486,6 @@ For full details of the options listed below, and their possible values, see | |||
481 | .It SendEnv | 486 | .It SendEnv |
482 | .It ServerAliveInterval | 487 | .It ServerAliveInterval |
483 | .It ServerAliveCountMax | 488 | .It ServerAliveCountMax |
484 | .It SmartcardDevice | ||
485 | .It StrictHostKeyChecking | 489 | .It StrictHostKeyChecking |
486 | .It TCPKeepAlive | 490 | .It TCPKeepAlive |
487 | .It Tunnel | 491 | .It Tunnel |
@@ -601,6 +605,19 @@ Multiple | |||
601 | .Fl v | 605 | .Fl v |
602 | options increase the verbosity. | 606 | options increase the verbosity. |
603 | The maximum is 3. | 607 | The maximum is 3. |
608 | .It Fl W Ar host : Ns Ar port | ||
609 | Requests that standard input and output on the client be forwarded to | ||
610 | .Ar host | ||
611 | on | ||
612 | .Ar port | ||
613 | over the secure channel. | ||
614 | Implies | ||
615 | .Fl N , | ||
616 | .Fl T , | ||
617 | .Cm ExitOnForwardFailure | ||
618 | and | ||
619 | .Cm ClearAllForwardings | ||
620 | and works with Protocol version 2 only. | ||
604 | .It Fl w Xo | 621 | .It Fl w Xo |
605 | .Ar local_tun Ns Op : Ns Ar remote_tun | 622 | .Ar local_tun Ns Op : Ns Ar remote_tun |
606 | .Xc | 623 | .Xc |
@@ -674,20 +691,18 @@ exits with the exit status of the remote command or with 255 | |||
674 | if an error occurred. | 691 | if an error occurred. |
675 | .Sh AUTHENTICATION | 692 | .Sh AUTHENTICATION |
676 | The OpenSSH SSH client supports SSH protocols 1 and 2. | 693 | The OpenSSH SSH client supports SSH protocols 1 and 2. |
677 | Protocol 2 is the default, with | 694 | The default is to use protocol 2 only, |
678 | .Nm | 695 | though this can be changed via the |
679 | falling back to protocol 1 if it detects protocol 2 is unsupported. | ||
680 | These settings may be altered using the | ||
681 | .Cm Protocol | 696 | .Cm Protocol |
682 | option in | 697 | option in |
683 | .Xr ssh_config 5 , | 698 | .Xr ssh_config 5 |
684 | or enforced using the | 699 | or the |
685 | .Fl 1 | 700 | .Fl 1 |
686 | and | 701 | and |
687 | .Fl 2 | 702 | .Fl 2 |
688 | options (see above). | 703 | options (see above). |
689 | Both protocols support similar authentication methods, | 704 | Both protocols support similar authentication methods, |
690 | but protocol 2 is preferred since | 705 | but protocol 2 is the default since |
691 | it provides additional mechanisms for confidentiality | 706 | it provides additional mechanisms for confidentiality |
692 | (the traffic is encrypted using AES, 3DES, Blowfish, CAST128, or Arcfour) | 707 | (the traffic is encrypted using AES, 3DES, Blowfish, CAST128, or Arcfour) |
693 | and integrity (hmac-md5, hmac-sha1, umac-64, hmac-ripemd160). | 708 | and integrity (hmac-md5, hmac-sha1, umac-64, hmac-ripemd160). |
@@ -800,8 +815,20 @@ file, and has one key | |||
800 | per line, though the lines can be very long. | 815 | per line, though the lines can be very long. |
801 | After this, the user can log in without giving the password. | 816 | After this, the user can log in without giving the password. |
802 | .Pp | 817 | .Pp |
803 | The most convenient way to use public key authentication may be with an | 818 | A variation on public key authentication |
804 | authentication agent. | 819 | is available in the form of certificate authentication: |
820 | instead of a set of public/private keys, | ||
821 | signed certificates are used. | ||
822 | This has the advantage that a single trusted certification authority | ||
823 | can be used in place of many public/private keys. | ||
824 | See the | ||
825 | .Sx CERTIFICATES | ||
826 | section of | ||
827 | .Xr ssh-keygen 1 | ||
828 | for more information. | ||
829 | .Pp | ||
830 | The most convenient way to use public key or certificate authentication | ||
831 | may be with an authentication agent. | ||
805 | See | 832 | See |
806 | .Xr ssh-agent 1 | 833 | .Xr ssh-agent 1 |
807 | for more information. | 834 | for more information. |