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authordes <des@FreeBSD.org>2016-01-19 18:28:23 +0000
committerdes <des@FreeBSD.org>2016-01-19 18:28:23 +0000
commit7a7bc643b5dd94f6333f2a1d91923165ad77176f (patch)
tree9d2b367395b2d3c9a63b4aecd1eb28b17b838703 /crypto/openssh/ssh_config.5
parent834fb5aff44e0a606772591d869016a1d8d9aa95 (diff)
parent928d872bfcc9d49be194dc51d80555f1bbdbff6b (diff)
downloadFreeBSD-src-7a7bc643b5dd94f6333f2a1d91923165ad77176f.zip
FreeBSD-src-7a7bc643b5dd94f6333f2a1d91923165ad77176f.tar.gz
Upgrade to OpenSSH 6.8p1.
Diffstat (limited to 'crypto/openssh/ssh_config.5')
-rw-r--r--crypto/openssh/ssh_config.5152
1 files changed, 133 insertions, 19 deletions
diff --git a/crypto/openssh/ssh_config.5 b/crypto/openssh/ssh_config.5
index 6049e4a..16769a4 100644
--- a/crypto/openssh/ssh_config.5
+++ b/crypto/openssh/ssh_config.5
@@ -33,9 +33,9 @@
.\" (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_config.5,v 1.191 2014/07/15 15:54:14 millert Exp $
+.\" $OpenBSD: ssh_config.5,v 1.205 2015/02/20 22:17:21 djm Exp $
.\" $FreeBSD$
-.Dd $Mdocdate: July 15 2014 $
+.Dd $Mdocdate: February 20 2015 $
.Dt SSH_CONFIG 5
.Os
.Sh NAME
@@ -66,7 +66,10 @@ The configuration files contain sections separated by
.Dq Host
specifications, and that section is only applied for hosts that
match one of the patterns given in the specification.
-The matched host name is the one given on the command line.
+The matched host name is usually the one given on the command line
+(see the
+.Cm CanonicalizeHostname
+option for exceptions.)
.Pp
Since the first obtained value for each parameter is used, more
host-specific declarations should be given near the beginning of the
@@ -110,10 +113,12 @@ A single
.Ql *
as a pattern can be used to provide global
defaults for all hosts.
-The host is the
+The host is usually the
.Ar hostname
-argument given on the command line (i.e. the name is not converted to
-a canonicalized host name before matching).
+argument given on the command line
+(see the
+.Cm CanonicalizeHostname
+option for exceptions.)
.Pp
A pattern entry may be negated by prefixing it with an exclamation mark
.Pq Sq !\& .
@@ -135,19 +140,40 @@ or
keyword) to be used only when the conditions following the
.Cm Match
keyword are satisfied.
-Match conditions are specified using one or more keyword/criteria pairs
+Match conditions are specified using one or more critera
or the single token
.Cm all
-which matches all criteria.
-The available keywords are:
+which always matches.
+The available criteria keywords are:
+.Cm canonical ,
.Cm exec ,
.Cm host ,
.Cm originalhost ,
.Cm user ,
and
.Cm localuser .
+The
+.Cm all
+criteria must appear alone or immediately after
+.Cm canonical .
+Other criteria may be combined arbitrarily.
+All criteria but
+.Cm all
+and
+.Cm canonical
+require an argument.
+Criteria may be negated by prepending an exclamation mark
+.Pq Sq !\& .
.Pp
The
+.Cm canonical
+keywork matches only when the configuration file is being re-parsed
+after hostname canonicalization (see the
+.Cm CanonicalizeHostname
+option.)
+This may be useful to specify conditions that work with canonical host
+names only.
+The
.Cm exec
keyword executes the specified command under the user's shell.
If the command returns a zero exit status then the condition is considered true.
@@ -180,7 +206,9 @@ The criteria for the
keyword are matched against the target hostname, after any substitution
by the
.Cm Hostname
-option.
+or
+.Cm CanonicalizeHostname
+options.
The
.Cm originalhost
keyword matches against the hostname as it was specified on the command-line.
@@ -265,10 +293,11 @@ is set to
.Dq always ,
then canonicalization is applied to proxied connections too.
.Pp
-If this option is enabled and canonicalisation results in the target hostname
-changing, then the configuration files are processed again using the new
-target name to pick up any new configuration in matching
+If this option is enabled, then the configuration files are processed
+again using the new target name to pick up any new configuration in matching
.Cm Host
+and
+.Cm Match
stanzas.
.It Cm CanonicalizeMaxDots
Specifies the maximum number of dot characters in a hostname before
@@ -389,7 +418,9 @@ aes192-cbc,aes256-cbc,arcfour
The list of available ciphers may also be obtained using the
.Fl Q
option of
-.Xr ssh 1 .
+.Xr ssh 1
+with an argument of
+.Dq cipher .
.It Cm ClearAllForwardings
Specifies that all local, remote, and dynamic port forwardings
specified in the configuration files or on the command line be
@@ -509,7 +540,8 @@ by a hash of the concatenation: %l%h%p%r.
It is recommended that any
.Cm ControlPath
used for opportunistic connection sharing include
-at least %h, %p, and %r (or alternatively %C).
+at least %h, %p, and %r (or alternatively %C) and be placed in a directory
+that is not writable by other users.
This ensures that shared connections are uniquely identified.
.It Cm ControlPersist
When used in conjunction with
@@ -522,7 +554,9 @@ If set to
then the master connection will not be placed into the background,
and will close as soon as the initial client connection is closed.
If set to
-.Dq yes ,
+.Dq yes
+or
+.Dq 0 ,
then the master connection will remain in the background indefinitely
(until killed or closed via a mechanism such as the
.Xr ssh 1
@@ -607,6 +641,14 @@ or
.Dq no .
The default is
.Dq no .
+.It Cm FingerprintHash
+Specifies the hash algorithm used when displaying key fingerprints.
+Valid options are:
+.Dq md5
+and
+.Dq sha256 .
+The default is
+.Dq sha256 .
.It Cm ForwardAgent
Specifies whether the connection to the authentication agent (if any)
will be forwarded to the remote machine.
@@ -736,6 +778,17 @@ The default is
This option applies to protocol version 2 only and
is similar to
.Cm RhostsRSAAuthentication .
+.It Cm HostbasedKeyTypes
+Specifies the key types that will be used for hostbased authentication
+as a comma-separated pattern list.
+The default
+.Dq *
+will allow all key types.
+The
+.Fl Q
+option of
+.Xr ssh 1
+may be used to list supported key types.
.It Cm HostKeyAlgorithms
Specifies the protocol version 2 host key algorithms
that the client wants to use in order of preference.
@@ -753,6 +806,13 @@ ssh-ed25519,ssh-rsa,ssh-dss
.Pp
If hostkeys are known for the destination host then this default is modified
to prefer their algorithms.
+.Pp
+The list of available key types may also be obtained using the
+.Fl Q
+option of
+.Xr ssh 1
+with an argument of
+.Dq key .
.It Cm HostKeyAlias
Specifies an alias that should be used instead of the
real host name when looking up or saving the host key
@@ -796,7 +856,7 @@ offers many different identities.
The default is
.Dq no .
.It Cm IdentityFile
-Specifies a file from which the user's DSA, ECDSA, ED25519 or RSA authentication
+Specifies a file from which the user's DSA, ECDSA, Ed25519 or RSA authentication
identity is read.
The default is
.Pa ~/.ssh/identity
@@ -923,6 +983,13 @@ diffie-hellman-group14-sha1,
diffie-hellman-group-exchange-sha1,
diffie-hellman-group1-sha1
.Ed
+.Pp
+The list of available key exchange algorithms may also be obtained using the
+.Fl Q
+option of
+.Xr ssh 1
+with an argument of
+.Dq kex .
.It Cm LocalCommand
Specifies a command to execute on the local machine after successfully
connecting to the server.
@@ -1012,6 +1079,13 @@ hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,
hmac-md5,hmac-sha1,hmac-ripemd160,
hmac-sha1-96,hmac-md5-96
.Ed
+.Pp
+The list of available MAC algorithms may also be obtained using the
+.Fl Q
+option of
+.Xr ssh 1
+with an argument of
+.Dq mac .
.It Cm NoHostAuthenticationForLocalhost
This option can be used if the home directory is shared across machines.
In this case localhost will refer to a different machine on each of
@@ -1222,6 +1296,16 @@ and
.Fl T
flags for
.Xr ssh 1 .
+.It Cm RevokedHostKeys
+Specifies revoked host public keys.
+Keys listed in this file will be refused for host authentication.
+Note that if this file does not exist or is not readable,
+then host authentication will be refused for all hosts.
+Keys may be specified as a text file, listing one public key per line, or as
+an OpenSSH Key Revocation List (KRL) as generated by
+.Xr ssh-keygen 1 .
+For more information on KRLs, see the KEY REVOCATION LISTS section in
+.Xr ssh-keygen 1 .
.It Cm RhostsRSAAuthentication
Specifies whether to try rhosts based authentication with RSA host
authentication.
@@ -1420,6 +1504,36 @@ is not specified, it defaults to
.Dq any .
The default is
.Dq any:any .
+.It Cm UpdateHostKeys
+Specifies whether
+.Xr ssh 1
+should accept notifications of additional hostkeys from the server sent
+after authentication has completed and add them to
+.Cm UserKnownHostsFile .
+The argument must be
+.Dq yes ,
+.Dq no
+(the default) or
+.Dq ask .
+Enabling this option allows learning alternate hostkeys for a server
+and supports graceful key rotation by allowing a server to send replacement
+public keys before old ones are removed.
+Additional hostkeys are only accepted if the key used to authenticate the
+host was already trusted or explicity accepted by the user.
+If
+.Cm UpdateHostKeys
+is set to
+.Dq ask ,
+then the user is asked to confirm the modifications to the known_hosts file.
+Confirmation is currently incompatible with
+.Cm ControlPersist ,
+and will be disabled if it is enabled.
+.Pp
+Presently, only
+.Xr sshd 8
+from OpenSSH 6.8 and greater support the
+.Dq hostkeys@openssh.com
+protocol extension used to inform the client of all the server's hostkeys.
.It Cm UsePrivilegedPort
Specifies whether to use a privileged port for outgoing connections.
The argument must be
@@ -1489,12 +1603,12 @@ may be used to disable this.
If this flag is set to
.Dq yes ,
an ASCII art representation of the remote host key fingerprint is
-printed in addition to the hex fingerprint string at login and
+printed in addition to the fingerprint string at login and
for unknown host keys.
If this flag is set to
.Dq no ,
no fingerprint strings are printed at login and
-only the hex fingerprint string will be printed for unknown host keys.
+only the fingerprint string will be printed for unknown host keys.
The default is
.Dq no .
.It Cm XAuthLocation
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