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-rw-r--r--sshd_config.5113
1 files changed, 93 insertions, 20 deletions
diff --git a/sshd_config.5 b/sshd_config.5
index e3c7c3936..e1b54ba20 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -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: sshd_config.5,v 1.263 2018/02/16 02:40:45 djm Exp $ 36.\" $OpenBSD: sshd_config.5,v 1.281 2018/07/20 05:01:10 djm Exp $
37.Dd $Mdocdate: February 16 2018 $ 37.Dd $Mdocdate: July 20 2018 $
38.Dt SSHD_CONFIG 5 38.Dt SSHD_CONFIG 5
39.Os 39.Os
40.Sh NAME 40.Sh NAME
@@ -66,12 +66,14 @@ the session's
66.Xr environ 7 . 66.Xr environ 7 .
67See 67See
68.Cm SendEnv 68.Cm SendEnv
69and
70.Cm SetEnv
69in 71in
70.Xr ssh_config 5 72.Xr ssh_config 5
71for how to configure the client. 73for how to configure the client.
72The 74The
73.Ev TERM 75.Ev TERM
74environment variable is always sent whenever the client 76environment variable is always accepted whenever the client
75requests a pseudo-terminal as it is required by the protocol. 77requests a pseudo-terminal as it is required by the protocol.
76Variables are specified by name, which may contain the wildcard characters 78Variables are specified by name, which may contain the wildcard characters
77.Ql * 79.Ql *
@@ -184,7 +186,7 @@ for more information on patterns.
184.It Cm AuthenticationMethods 186.It Cm AuthenticationMethods
185Specifies the authentication methods that must be successfully completed 187Specifies the authentication methods that must be successfully completed
186for a user to be granted access. 188for a user to be granted access.
187This option must be followed by one or more comma-separated lists of 189This option must be followed by one or more lists of comma-separated
188authentication method names, or by the single string 190authentication method names, or by the single string
189.Cm any 191.Cm any
190to indicate the default behaviour of accepting any single authentication 192to indicate the default behaviour of accepting any single authentication
@@ -203,10 +205,9 @@ keyboard-interactive authentication before public key.
203For keyboard interactive authentication it is also possible to 205For keyboard interactive authentication it is also possible to
204restrict authentication to a specific device by appending a 206restrict authentication to a specific device by appending a
205colon followed by the device identifier 207colon followed by the device identifier
206.Cm bsdauth , 208.Cm bsdauth
207.Cm pam ,
208or 209or
209.Cm skey , 210.Cm pam .
210depending on the server configuration. 211depending on the server configuration.
211For example, 212For example,
212.Qq keyboard-interactive:bsdauth 213.Qq keyboard-interactive:bsdauth
@@ -231,7 +232,7 @@ The available authentication methods are:
231.Qq keyboard-interactive , 232.Qq keyboard-interactive ,
232.Qq none 233.Qq none
233(used for access to password-less accounts when 234(used for access to password-less accounts when
234.Cm PermitEmptyPassword 235.Cm PermitEmptyPasswords
235is enabled), 236is enabled),
236.Qq password 237.Qq password
237and 238and
@@ -657,7 +658,7 @@ The default is
657.Cm yes . 658.Cm yes .
658.It Cm HostbasedAcceptedKeyTypes 659.It Cm HostbasedAcceptedKeyTypes
659Specifies the key types that will be accepted for hostbased authentication 660Specifies the key types that will be accepted for hostbased authentication
660as a comma-separated pattern list. 661as a list of comma-separated patterns.
661Alternately if the specified value begins with a 662Alternately if the specified value begins with a
662.Sq + 663.Sq +
663character, then the specified key types will be appended to the default set 664character, then the specified key types will be appended to the default set
@@ -672,9 +673,10 @@ ecdsa-sha2-nistp256-cert-v01@openssh.com,
672ecdsa-sha2-nistp384-cert-v01@openssh.com, 673ecdsa-sha2-nistp384-cert-v01@openssh.com,
673ecdsa-sha2-nistp521-cert-v01@openssh.com, 674ecdsa-sha2-nistp521-cert-v01@openssh.com,
674ssh-ed25519-cert-v01@openssh.com, 675ssh-ed25519-cert-v01@openssh.com,
676rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,
675ssh-rsa-cert-v01@openssh.com, 677ssh-rsa-cert-v01@openssh.com,
676ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521, 678ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
677ssh-ed25519,ssh-rsa 679ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
678.Ed 680.Ed
679.Pp 681.Pp
680The list of available key types may also be obtained using 682The list of available key types may also be obtained using
@@ -749,9 +751,10 @@ ecdsa-sha2-nistp256-cert-v01@openssh.com,
749ecdsa-sha2-nistp384-cert-v01@openssh.com, 751ecdsa-sha2-nistp384-cert-v01@openssh.com,
750ecdsa-sha2-nistp521-cert-v01@openssh.com, 752ecdsa-sha2-nistp521-cert-v01@openssh.com,
751ssh-ed25519-cert-v01@openssh.com, 753ssh-ed25519-cert-v01@openssh.com,
754rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,
752ssh-rsa-cert-v01@openssh.com, 755ssh-rsa-cert-v01@openssh.com,
753ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521, 756ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
754ssh-ed25519,ssh-rsa 757ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
755.Ed 758.Ed
756.Pp 759.Pp
757The list of available key types may also be obtained using 760The list of available key types may also be obtained using
@@ -816,9 +819,11 @@ If one argument is specified, it is used as the packet class unconditionally.
816If two values are specified, the first is automatically selected for 819If two values are specified, the first is automatically selected for
817interactive sessions and the second for non-interactive sessions. 820interactive sessions and the second for non-interactive sessions.
818The default is 821The default is
819.Cm lowdelay 822.Cm af21
823(Low-Latency Data)
820for interactive sessions and 824for interactive sessions and
821.Cm throughput 825.Cm cs1
826(Lower Effort)
822for non-interactive sessions. 827for non-interactive sessions.
823.It Cm KbdInteractiveAuthentication 828.It Cm KbdInteractiveAuthentication
824Specifies whether to allow keyboard-interactive authentication. 829Specifies whether to allow keyboard-interactive authentication.
@@ -1123,6 +1128,7 @@ Available keywords are
1123.Cm MaxSessions , 1128.Cm MaxSessions ,
1124.Cm PasswordAuthentication , 1129.Cm PasswordAuthentication ,
1125.Cm PermitEmptyPasswords , 1130.Cm PermitEmptyPasswords ,
1131.Cm PermitListen ,
1126.Cm PermitOpen , 1132.Cm PermitOpen ,
1127.Cm PermitRootLogin , 1133.Cm PermitRootLogin ,
1128.Cm PermitTTY , 1134.Cm PermitTTY ,
@@ -1133,6 +1139,7 @@ Available keywords are
1133.Cm RekeyLimit , 1139.Cm RekeyLimit ,
1134.Cm RevokedKeys , 1140.Cm RevokedKeys ,
1135.Cm RDomain , 1141.Cm RDomain ,
1142.Cm SetEnv ,
1136.Cm StreamLocalBindMask , 1143.Cm StreamLocalBindMask ,
1137.Cm StreamLocalBindUnlink , 1144.Cm StreamLocalBindUnlink ,
1138.Cm TrustedUserCAKeys , 1145.Cm TrustedUserCAKeys ,
@@ -1182,6 +1189,48 @@ When password authentication is allowed, it specifies whether the
1182server allows login to accounts with empty password strings. 1189server allows login to accounts with empty password strings.
1183The default is 1190The default is
1184.Cm no . 1191.Cm no .
1192.It Cm PermitListen
1193Specifies the addresses/ports on which a remote TCP port forwarding may listen.
1194The listen specification must be one of the following forms:
1195.Pp
1196.Bl -item -offset indent -compact
1197.It
1198.Cm PermitListen
1199.Sm off
1200.Ar port
1201.Sm on
1202.It
1203.Cm PermitListen
1204.Sm off
1205.Ar host : port
1206.Sm on
1207.El
1208.Pp
1209Multiple permissions may be specified by separating them with whitespace.
1210An argument of
1211.Cm any
1212can be used to remove all restrictions and permit any listen requests.
1213An argument of
1214.Cm none
1215can be used to prohibit all listen requests.
1216The host name may contain wildcards as described in the PATTERNS section in
1217.Xr ssh_config 5 .
1218The wildcard
1219.Sq *
1220can also be used in place of a port number to allow all ports.
1221By default all port forwarding listen requests are permitted.
1222Note that the
1223.Cm GatewayPorts
1224option may further restrict which addresses may be listened on.
1225Note also that
1226.Xr ssh 1
1227will request a listen host of
1228.Dq localhost
1229if no listen host was specifically requested, and this this name is
1230treated differently to explicit localhost addresses of
1231.Dq 127.0.0.1
1232and
1233.Dq ::1 .
1185.It Cm PermitOpen 1234.It Cm PermitOpen
1186Specifies the destinations to which TCP port forwarding is permitted. 1235Specifies the destinations to which TCP port forwarding is permitted.
1187The forwarding specification must be one of the following forms: 1236The forwarding specification must be one of the following forms:
@@ -1284,6 +1333,12 @@ options in
1284.Pa ~/.ssh/authorized_keys 1333.Pa ~/.ssh/authorized_keys
1285are processed by 1334are processed by
1286.Xr sshd 8 . 1335.Xr sshd 8 .
1336Valid options are
1337.Cm yes ,
1338.Cm no
1339or a pattern-list specifying which environment variable names to accept
1340(for example
1341.Qq LANG,LC_* ) .
1287The default is 1342The default is
1288.Cm no . 1343.Cm no .
1289Enabling environment processing may enable users to bypass access 1344Enabling environment processing may enable users to bypass access
@@ -1330,7 +1385,7 @@ The default is
1330.Cm yes . 1385.Cm yes .
1331.It Cm PubkeyAcceptedKeyTypes 1386.It Cm PubkeyAcceptedKeyTypes
1332Specifies the key types that will be accepted for public key authentication 1387Specifies the key types that will be accepted for public key authentication
1333as a comma-separated pattern list. 1388as a list of comma-separated patterns.
1334Alternately if the specified value begins with a 1389Alternately if the specified value begins with a
1335.Sq + 1390.Sq +
1336character, then the specified key types will be appended to the default set 1391character, then the specified key types will be appended to the default set
@@ -1345,9 +1400,10 @@ ecdsa-sha2-nistp256-cert-v01@openssh.com,
1345ecdsa-sha2-nistp384-cert-v01@openssh.com, 1400ecdsa-sha2-nistp384-cert-v01@openssh.com,
1346ecdsa-sha2-nistp521-cert-v01@openssh.com, 1401ecdsa-sha2-nistp521-cert-v01@openssh.com,
1347ssh-ed25519-cert-v01@openssh.com, 1402ssh-ed25519-cert-v01@openssh.com,
1403rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,
1348ssh-rsa-cert-v01@openssh.com, 1404ssh-rsa-cert-v01@openssh.com,
1349ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521, 1405ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
1350ssh-ed25519,ssh-rsa 1406ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
1351.Ed 1407.Ed
1352.Pp 1408.Pp
1353The list of available key types may also be obtained using 1409The list of available key types may also be obtained using
@@ -1402,6 +1458,21 @@ will be bound to this
1402If the routing domain is set to 1458If the routing domain is set to
1403.Cm \&%D , 1459.Cm \&%D ,
1404then the domain in which the incoming connection was received will be applied. 1460then the domain in which the incoming connection was received will be applied.
1461.It Cm SetEnv
1462Specifies one or more environment variables to set in child sessions started
1463by
1464.Xr sshd 8
1465as
1466.Dq NAME=VALUE .
1467The environment value may be quoted (e.g. if it contains whitespace
1468characters).
1469Environment variables set by
1470.Cm SetEnv
1471override the default environment and any variables specified by the user
1472via
1473.Cm AcceptEnv
1474or
1475.Cm PermitUserEnvironment .
1405.It Cm StreamLocalBindMask 1476.It Cm StreamLocalBindMask
1406Sets the octal file creation mode mask 1477Sets the octal file creation mode mask
1407.Pq umask 1478.Pq umask
@@ -1687,24 +1758,26 @@ The serial number of the certificate.
1687The type of the CA key. 1758The type of the CA key.
1688.It %t 1759.It %t
1689The key or certificate type. 1760The key or certificate type.
1761.It \&%U
1762The numeric user ID of the target user.
1690.It %u 1763.It %u
1691The username. 1764The username.
1692.El 1765.El
1693.Pp 1766.Pp
1694.Cm AuthorizedKeysCommand 1767.Cm AuthorizedKeysCommand
1695accepts the tokens %%, %f, %h, %k, %t, and %u. 1768accepts the tokens %%, %f, %h, %k, %t, %U, and %u.
1696.Pp 1769.Pp
1697.Cm AuthorizedKeysFile 1770.Cm AuthorizedKeysFile
1698accepts the tokens %%, %h, and %u. 1771accepts the tokens %%, %h, %U, and %u.
1699.Pp 1772.Pp
1700.Cm AuthorizedPrincipalsCommand 1773.Cm AuthorizedPrincipalsCommand
1701accepts the tokens %%, %F, %f, %h, %i, %K, %k, %s, %T, %t, and %u. 1774accepts the tokens %%, %F, %f, %h, %i, %K, %k, %s, %T, %t, %U, and %u.
1702.Pp 1775.Pp
1703.Cm AuthorizedPrincipalsFile 1776.Cm AuthorizedPrincipalsFile
1704accepts the tokens %%, %h, and %u. 1777accepts the tokens %%, %h, %U, and %u.
1705.Pp 1778.Pp
1706.Cm ChrootDirectory 1779.Cm ChrootDirectory
1707accepts the tokens %%, %h, and %u. 1780accepts the tokens %%, %h, %U, and %u.
1708.Pp 1781.Pp
1709.Cm RoutingDomain 1782.Cm RoutingDomain
1710accepts the token %D. 1783accepts the token %D.