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-rw-r--r--ssh.192
1 files changed, 31 insertions, 61 deletions
diff --git a/ssh.1 b/ssh.1
index 4011c65aa..2ab1697f9 100644
--- a/ssh.1
+++ b/ssh.1
@@ -33,8 +33,8 @@
33.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35.\" 35.\"
36.\" $OpenBSD: ssh.1,v 1.376 2016/07/16 06:57:55 jmc Exp $ 36.\" $OpenBSD: ssh.1,v 1.384 2017/09/21 19:16:53 markus Exp $
37.Dd $Mdocdate: July 16 2016 $ 37.Dd $Mdocdate: September 21 2017 $
38.Dt SSH 1 38.Dt SSH 1
39.Os 39.Os
40.Sh NAME 40.Sh NAME
@@ -43,7 +43,7 @@
43.Sh SYNOPSIS 43.Sh SYNOPSIS
44.Nm ssh 44.Nm ssh
45.Bk -words 45.Bk -words
46.Op Fl 1246AaCfGgKkMNnqsTtVvXxYy 46.Op Fl 46AaCfGgKkMNnqsTtVvXxYy
47.Op Fl b Ar bind_address 47.Op Fl b Ar bind_address
48.Op Fl c Ar cipher_spec 48.Op Fl c Ar cipher_spec
49.Op Fl D Oo Ar bind_address : Oc Ns Ar port 49.Op Fl D Oo Ar bind_address : Oc Ns Ar port
@@ -95,16 +95,6 @@ it is executed on the remote host instead of a login shell.
95The options are as follows: 95The options are as follows:
96.Pp 96.Pp
97.Bl -tag -width Ds -compact 97.Bl -tag -width Ds -compact
98.It Fl 1
99Forces
100.Nm
101to try protocol version 1 only.
102.Pp
103.It Fl 2
104Forces
105.Nm
106to try protocol version 2 only.
107.Pp
108.It Fl 4 98.It Fl 4
109Forces 99Forces
110.Nm 100.Nm
@@ -144,12 +134,7 @@ data for forwarded X11, TCP and
144.Ux Ns -domain 134.Ux Ns -domain
145connections). 135connections).
146The compression algorithm is the same used by 136The compression algorithm is the same used by
147.Xr gzip 1 , 137.Xr gzip 1 .
148and the
149.Dq level
150can be controlled by the
151.Cm CompressionLevel
152option for protocol version 1.
153Compression is desirable on modem lines and other 138Compression is desirable on modem lines and other
154slow connections, but will only slow down things on fast networks. 139slow connections, but will only slow down things on fast networks.
155The default value can be set on a host-by-host basis in the 140The default value can be set on a host-by-host basis in the
@@ -159,14 +144,6 @@ option.
159.Pp 144.Pp
160.It Fl c Ar cipher_spec 145.It Fl c Ar cipher_spec
161Selects the cipher specification for encrypting the session. 146Selects the cipher specification for encrypting the session.
162.Pp
163Protocol version 1 allows specification of a single cipher.
164The supported values are
165.Dq 3des ,
166.Dq blowfish ,
167and
168.Dq des .
169For protocol version 2,
170.Ar cipher_spec 147.Ar cipher_spec
171is a comma-separated list of ciphers 148is a comma-separated list of ciphers
172listed in order of preference. 149listed in order of preference.
@@ -290,14 +267,11 @@ private RSA key.
290Selects a file from which the identity (private key) for 267Selects a file from which the identity (private key) for
291public key authentication is read. 268public key authentication is read.
292The default is 269The default is
293.Pa ~/.ssh/identity
294for protocol version 1, and
295.Pa ~/.ssh/id_dsa , 270.Pa ~/.ssh/id_dsa ,
296.Pa ~/.ssh/id_ecdsa , 271.Pa ~/.ssh/id_ecdsa ,
297.Pa ~/.ssh/id_ed25519 272.Pa ~/.ssh/id_ed25519
298and 273and
299.Pa ~/.ssh/id_rsa 274.Pa ~/.ssh/id_rsa .
300for protocol version 2.
301Identity files may also be specified on 275Identity files may also be specified on
302a per-host basis in the configuration file. 276a per-host basis in the configuration file.
303It is possible to have multiple 277It is possible to have multiple
@@ -491,11 +465,9 @@ For full details of the options listed below, and their possible values, see
491.It CertificateFile 465.It CertificateFile
492.It ChallengeResponseAuthentication 466.It ChallengeResponseAuthentication
493.It CheckHostIP 467.It CheckHostIP
494.It Cipher
495.It Ciphers 468.It Ciphers
496.It ClearAllForwardings 469.It ClearAllForwardings
497.It Compression 470.It Compression
498.It CompressionLevel
499.It ConnectionAttempts 471.It ConnectionAttempts
500.It ConnectTimeout 472.It ConnectTimeout
501.It ControlMaster 473.It ControlMaster
@@ -540,17 +512,15 @@ For full details of the options listed below, and their possible values, see
540.It PKCS11Provider 512.It PKCS11Provider
541.It Port 513.It Port
542.It PreferredAuthentications 514.It PreferredAuthentications
543.It Protocol
544.It ProxyCommand 515.It ProxyCommand
545.It ProxyJump 516.It ProxyJump
546.It ProxyUseFdpass 517.It ProxyUseFdpass
547.It PubkeyAcceptedKeyTypes 518.It PubkeyAcceptedKeyTypes
548.It PubkeyAuthentication 519.It PubkeyAuthentication
549.It RekeyLimit 520.It RekeyLimit
521.It RemoteCommand
550.It RemoteForward 522.It RemoteForward
551.It RequestTTY 523.It RequestTTY
552.It RhostsRSAAuthentication
553.It RSAAuthentication
554.It SendEnv 524.It SendEnv
555.It ServerAliveInterval 525.It ServerAliveInterval
556.It ServerAliveCountMax 526.It ServerAliveCountMax
@@ -622,21 +592,30 @@ Causes most warning and diagnostic messages to be suppressed.
622.Ar remote_socket : local_socket 592.Ar remote_socket : local_socket
623.Sm on 593.Sm on
624.Xc 594.Xc
595.It Fl R Xo
596.Sm off
597.Oo Ar bind_address : Oc
598.Ar port
599.Sm on
600.Xc
625Specifies that connections to the given TCP port or Unix socket on the remote 601Specifies that connections to the given TCP port or Unix socket on the remote
626(server) host are to be forwarded to the given host and port, or Unix socket, 602(server) host are to be forwarded to the local side.
627on the local side. 603.Pp
628This works by allocating a socket to listen to either a TCP 604This works by allocating a socket to listen to either a TCP
629.Ar port 605.Ar port
630or to a Unix socket on the remote side. 606or to a Unix socket on the remote side.
631Whenever a connection is made to this port or Unix socket, the 607Whenever a connection is made to this port or Unix socket, the
632connection is forwarded over the secure channel, and a connection 608connection is forwarded over the secure channel, and a connection
633is made to either 609is made from the local machine to either an explicit destination specified by
634.Ar host 610.Ar host
635port 611port
636.Ar hostport , 612.Ar hostport ,
637or 613or
638.Ar local_socket , 614.Ar local_socket ,
639from the local machine. 615or, if no explicit destination was specified,
616.Nm
617will act as a SOCKS 4/5 proxy and forward connections to the destinations
618requested by the remote SOCKS client.
640.Pp 619.Pp
641Port forwardings can also be specified in the configuration file. 620Port forwardings can also be specified in the configuration file.
642Privileged ports can be forwarded only when 621Privileged ports can be forwarded only when
@@ -806,21 +785,7 @@ a per-user configuration file and a system-wide configuration file.
806The file format and configuration options are described in 785The file format and configuration options are described in
807.Xr ssh_config 5 . 786.Xr ssh_config 5 .
808.Sh AUTHENTICATION 787.Sh AUTHENTICATION
809The OpenSSH SSH client supports SSH protocols 1 and 2. 788The OpenSSH SSH client supports SSH protocol 2.
810The default is to use protocol 2 only,
811though this can be changed via the
812.Cm Protocol
813option in
814.Xr ssh_config 5
815or the
816.Fl 1
817and
818.Fl 2
819options (see above).
820Protocol 1 should not be used
821and is only offered to support legacy devices.
822It suffers from a number of cryptographic weaknesses
823and doesn't support many of the advanced features available for protocol 2.
824.Pp 789.Pp
825The methods available for authentication are: 790The methods available for authentication are:
826GSSAPI-based authentication, 791GSSAPI-based authentication,
@@ -890,11 +855,20 @@ The client proves that it has access to the private key
890and the server checks that the corresponding public key 855and the server checks that the corresponding public key
891is authorized to accept the account. 856is authorized to accept the account.
892.Pp 857.Pp
858The server may inform the client of errors that prevented public key
859authentication from succeeding after authentication completes using a
860different method.
861These may be viewed by increasing the
862.Cm LogLevel
863to
864.Cm DEBUG
865or higher (e.g. by using the
866.Fl v
867flag).
868.Pp
893The user creates his/her key pair by running 869The user creates his/her key pair by running
894.Xr ssh-keygen 1 . 870.Xr ssh-keygen 1 .
895This stores the private key in 871This stores the private key in
896.Pa ~/.ssh/identity
897(protocol 1),
898.Pa ~/.ssh/id_dsa 872.Pa ~/.ssh/id_dsa
899(DSA), 873(DSA),
900.Pa ~/.ssh/id_ecdsa 874.Pa ~/.ssh/id_ecdsa
@@ -905,8 +879,6 @@ or
905.Pa ~/.ssh/id_rsa 879.Pa ~/.ssh/id_rsa
906(RSA) 880(RSA)
907and stores the public key in 881and stores the public key in
908.Pa ~/.ssh/identity.pub
909(protocol 1),
910.Pa ~/.ssh/id_dsa.pub 882.Pa ~/.ssh/id_dsa.pub
911(DSA), 883(DSA),
912.Pa ~/.ssh/id_ecdsa.pub 884.Pa ~/.ssh/id_ecdsa.pub
@@ -1490,7 +1462,6 @@ Contains additional definitions for environment variables; see
1490.Sx ENVIRONMENT , 1462.Sx ENVIRONMENT ,
1491above. 1463above.
1492.Pp 1464.Pp
1493.It Pa ~/.ssh/identity
1494.It Pa ~/.ssh/id_dsa 1465.It Pa ~/.ssh/id_dsa
1495.It Pa ~/.ssh/id_ecdsa 1466.It Pa ~/.ssh/id_ecdsa
1496.It Pa ~/.ssh/id_ed25519 1467.It Pa ~/.ssh/id_ed25519
@@ -1505,7 +1476,6 @@ It is possible to specify a passphrase when
1505generating the key which will be used to encrypt the 1476generating the key which will be used to encrypt the
1506sensitive part of this file using 3DES. 1477sensitive part of this file using 3DES.
1507.Pp 1478.Pp
1508.It Pa ~/.ssh/identity.pub
1509.It Pa ~/.ssh/id_dsa.pub 1479.It Pa ~/.ssh/id_dsa.pub
1510.It Pa ~/.ssh/id_ecdsa.pub 1480.It Pa ~/.ssh/id_ecdsa.pub
1511.It Pa ~/.ssh/id_ed25519.pub 1481.It Pa ~/.ssh/id_ed25519.pub