Clarify crypto policies documentation in manual pages

* All the options that are affected by crypto policies will mention that + and -
       work with built-in defaults and not the crypto-policies ones.
     * The line mentioning crypto policies will be the first one in the option description.
This commit is contained in:
Jakub Jelen 2020-03-26 14:53:18 +01:00
parent eb546ec1a7
commit a848054c8a

View File

@ -1,8 +1,15 @@
diff -up openssh/ssh_config.5.crypto-policies openssh/ssh_config.5
--- openssh/ssh_config.5.crypto-policies 2020-02-07 15:05:55.665451715 +0100
+++ openssh/ssh_config.5 2020-02-07 15:07:11.632641922 +0100
@@ -361,15 +361,15 @@ domains.
diff -up openssh-8.2p1/ssh_config.5.crypto-policies openssh-8.2p1/ssh_config.5
--- openssh-8.2p1/ssh_config.5.crypto-policies 2020-03-26 14:40:44.546775605 +0100
+++ openssh-8.2p1/ssh_config.5 2020-03-26 14:52:20.700649727 +0100
@@ -359,17 +359,17 @@ or
.Qq *.c.example.com
domains.
.It Cm CASignatureAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+.Pp
Specifies which algorithms are allowed for signing of certificates
by certificate authorities (CAs).
-The default is:
@ -15,15 +22,39 @@ diff -up openssh/ssh_config.5.crypto-policies openssh/ssh_config.5
will not accept host certificates signed using algorithms other than those
specified.
+.Pp
.It Cm CertificateFile
Specifies a file from which the user's certificate is read.
A corresponding private key must be provided separately in order
@@ -424,20 +424,25 @@ If the option is set to
.Cm no ,
the check will not be executed.
.It Cm Ciphers
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+.Pp
.It Cm CertificateFile
Specifies a file from which the user's certificate is read.
A corresponding private key must be provided separately in order
@@ -453,12 +453,10 @@ aes256-gcm@openssh.com
Specifies the ciphers allowed and their order of preference.
Multiple ciphers must be comma-separated.
If the specified list begins with a
.Sq +
-character, then the specified ciphers will be appended to the default set
+character, then the specified ciphers will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified ciphers (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified ciphers will be placed at the head of the
-default set.
+built-in default set.
.Pp
The supported ciphers are:
.Bd -literal -offset indent
@@ -453,13 +458,6 @@ aes256-gcm@openssh.com
chacha20-poly1305@openssh.com
.Ed
.Pp
@ -33,31 +64,59 @@ diff -up openssh/ssh_config.5.crypto-policies openssh/ssh_config.5
-aes128-ctr,aes192-ctr,aes256-ctr,
-aes128-gcm@openssh.com,aes256-gcm@openssh.com
-.Ed
-.Pp
The list of available ciphers may also be obtained using
.Qq ssh -Q cipher .
.It Cm ClearAllForwardings
@@ -812,6 +810,11 @@ command line will be passed untouched to
The default is
.Dq no .
.It Cm GSSAPIKexAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
.Pp
The list of available ciphers may also be obtained using
.Qq ssh -Q cipher .
@@ -824,9 +822,10 @@ gss-nistp256-sha256-,
+.Pp
The list of key exchange algorithms that are offered for GSSAPI
key exchange. Possible values are
.Bd -literal -offset 3n
@@ -824,10 +827,8 @@ gss-nistp256-sha256-,
gss-curve25519-sha256-
.Ed
.Pp
-The default is
-.Dq gss-group14-sha256-,gss-group16-sha512-,gss-nistp256-sha256-,
-gss-curve25519-sha256-,gss-group14-sha1-,gss-gex-sha1- .
This option only applies to connections using GSSAPI.
+.Pp
.It Cm HashKnownHosts
Indicates that
.Xr ssh 1
@@ -1149,29 +1150,25 @@ it may be zero or more of:
and
.Cm pam .
.It Cm KexAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
This option only applies to connections using GSSAPI.
.It Cm HashKnownHosts
Indicates that
@@ -1162,15 +1162,10 @@ If the specified list begins with a
+.Pp
Specifies the available KEX (Key Exchange) algorithms.
Multiple algorithms must be comma-separated.
If the specified list begins with a
.Sq +
-character, then the specified methods will be appended to the default set
+character, then the specified methods will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified methods (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified methods will be placed at the head of the
default set.
-default set.
-The default is:
-.Bd -literal -offset indent
-curve25519-sha256,curve25519-sha256@libssh.org,
@ -67,14 +126,41 @@ diff -up openssh/ssh_config.5.crypto-policies openssh/ssh_config.5
-diffie-hellman-group18-sha512,
-diffie-hellman-group14-sha256
-.Ed
+built-in default set.
.Pp
The list of available key exchange algorithms may also be obtained using
.Qq ssh -Q kex .
@@ -1231,37 +1228,33 @@ The default is INFO.
DEBUG and DEBUG1 are equivalent.
DEBUG2 and DEBUG3 each specify higher levels of verbose output.
.It Cm MACs
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+.Pp
Specifies the MAC (message authentication code) algorithms
in order of preference.
The MAC algorithm is used for data integrity protection.
Multiple algorithms must be comma-separated.
If the specified list begins with a
.Sq +
-character, then the specified algorithms will be appended to the default set
+character, then the specified algorithms will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified algorithms (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified algorithms will be placed at the head of the
-default set.
+built-in default set.
.Pp
The list of available key exchange algorithms may also be obtained using
.Qq ssh -Q kex .
@@ -1252,14 +1247,10 @@ The algorithms that contain
The algorithms that contain
.Qq -etm
calculate the MAC after encryption (encrypt-then-mac).
These are considered safer and their use recommended.
.Pp
@ -86,17 +172,35 @@ diff -up openssh/ssh_config.5.crypto-policies openssh/ssh_config.5
-umac-64@openssh.com,umac-128@openssh.com,
-hmac-sha2-256,hmac-sha2-512,hmac-sha1
-.Ed
-.Pp
The list of available MAC algorithms may also be obtained using
.Qq ssh -Q mac .
.It Cm NoHostAuthenticationForLocalhost
@@ -1394,36 +1387,25 @@ instead of continuing to execute and pas
The default is
.Cm no .
.It Cm PubkeyAcceptedKeyTypes
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
.Pp
The list of available MAC algorithms may also be obtained using
.Qq ssh -Q mac .
@@ -1407,22 +1398,10 @@ If the specified list begins with a
+.Pp
Specifies the key types that will be used for public key authentication
as a comma-separated list of patterns.
If the specified list begins with a
.Sq +
-character, then the key types after it will be appended to the default
+character, then the key types after it will be appended to the built-in default
instead of replacing it.
If the specified list begins with a
.Sq -
character, then the specified key types (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified key types will be placed at the head of the
default set.
-default set.
-The default for this option is:
-.Bd -literal -offset 3n
-ecdsa-sha2-nistp256-cert-v01@openssh.com,
@ -113,18 +217,22 @@ diff -up openssh/ssh_config.5.crypto-policies openssh/ssh_config.5
-ssh-ed25519,sk-ssh-ed25519@openssh.com,
-rsa-sha2-512,rsa-sha2-256,ssh-rsa
-.Ed
+built-in default set.
.Pp
The list of available key types may also be obtained using
.Qq ssh -Q PubkeyAcceptedKeyTypes .
diff -up openssh-8.2p1/sshd_config.5.crypto-policies openssh-8.2p1/sshd_config.5
--- openssh-8.2p1/sshd_config.5.crypto-policies 2020-03-26 14:40:44.530775355 +0100
+++ openssh-8.2p1/sshd_config.5 2020-03-26 14:48:56.732468099 +0100
@@ -375,16 +375,16 @@ If the argument is
then no banner is displayed.
By default, no banner is displayed.
.It Cm CASignatureAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
.Pp
The list of available key types may also be obtained using
.Qq ssh -Q PubkeyAcceptedKeyTypes .
diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
--- openssh/sshd_config.5.crypto-policies 2020-02-07 15:05:55.639451308 +0100
+++ openssh/sshd_config.5 2020-02-07 15:05:55.672451825 +0100
@@ -377,14 +377,14 @@ By default, no banner is displayed.
.It Cm CASignatureAlgorithms
+.Pp
Specifies which algorithms are allowed for signing of certificates
by certificate authorities (CAs).
-The default is:
@ -136,15 +244,39 @@ diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
Certificates signed using other algorithms will not be accepted for
public key or host-based authentication.
+.Pp
.It Cm ChallengeResponseAuthentication
Specifies whether challenge-response authentication is allowed (e.g. via
PAM or through authentication styles supported in
@@ -446,20 +446,25 @@ The default is
indicating not to
.Xr chroot 2 .
.It Cm Ciphers
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+.Pp
.It Cm ChallengeResponseAuthentication
Specifies whether challenge-response authentication is allowed (e.g. via
PAM or through authentication styles supported in
@@ -486,12 +486,10 @@ aes256-gcm@openssh.com
Specifies the ciphers allowed.
Multiple ciphers must be comma-separated.
If the specified list begins with a
.Sq +
-character, then the specified ciphers will be appended to the default set
+character, then the specified ciphers will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified ciphers (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified ciphers will be placed at the head of the
-default set.
+built-in default set.
.Pp
The supported ciphers are:
.Pp
@@ -486,13 +491,6 @@ aes256-gcm@openssh.com
chacha20-poly1305@openssh.com
.El
.Pp
@ -154,29 +286,54 @@ diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
-aes128-ctr,aes192-ctr,aes256-ctr,
-aes128-gcm@openssh.com,aes256-gcm@openssh.com
-.Ed
-.Pp
The list of available ciphers may also be obtained using
.Qq ssh -Q cipher .
.It Cm ClientAliveCountMax
@@ -681,22 +679,24 @@ For this to work
.Cm GSSAPIKeyExchange
needs to be enabled in the server and also used by the client.
.It Cm GSSAPIKexAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
.Pp
The list of available ciphers may also be obtained using
.Qq ssh -Q cipher .
@@ -693,9 +691,10 @@ gss-nistp256-sha256-,
+.Pp
The list of key exchange algorithms that are accepted by GSSAPI
key exchange. Possible values are
.Bd -literal -offset 3n
-gss-gex-sha1-,
-gss-group1-sha1-,
-gss-group14-sha1-,
-gss-group14-sha256-,
-gss-group16-sha512-,
-gss-nistp256-sha256-,
+gss-gex-sha1-
+gss-group1-sha1-
+gss-group14-sha1-
+gss-group14-sha256-
+gss-group16-sha512-
+gss-nistp256-sha256-
gss-curve25519-sha256-
.Ed
.Pp
-.Pp
-The default is
-.Dq gss-group14-sha256-,gss-group16-sha512-,gss-nistp256-sha256-,
-gss-curve25519-sha256-,gss-group14-sha1-,gss-gex-sha1- .
This option only applies to connections using GSSAPI.
+.Pp
.It Cm HostbasedAcceptedKeyTypes
Specifies the key types that will be accepted for hostbased authentication
as a list of comma-separated patterns.
@@ -793,25 +793,13 @@ is specified, the location of the socket
.Ev SSH_AUTH_SOCK
environment variable.
.It Cm HostKeyAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
This option only applies to connections using GSSAPI.
.It Cm HostbasedAcceptedKeyTypes
Specifies the key types that will be accepted for hostbased authentication
@@ -794,22 +794,10 @@ environment variable.
.It Cm HostKeyAlgorithms
+.Pp
Specifies the host key algorithms
that the server offers.
-The default for this option is:
@ -195,14 +352,40 @@ diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
-ssh-ed25519,sk-ssh-ed25519@openssh.com,
-rsa-sha2-512,rsa-sha2-256,ssh-rsa
-.Ed
-.Pp
The list of available key types may also be obtained using
.Qq ssh -Q HostKeyAlgorithms .
.It Cm IgnoreRhosts
@@ -943,20 +931,25 @@ Specifies whether to look at .k5login fi
The default is
.Cm yes .
.It Cm KexAlgorithms
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+.Pp
Specifies the available KEX (Key Exchange) algorithms.
Multiple algorithms must be comma-separated.
Alternately if the specified list begins with a
.Sq +
-character, then the specified methods will be appended to the default set
+character, then the specified methods will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified methods (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified methods will be placed at the head of the
-default set.
+built-in default set.
The supported algorithms are:
.Pp
The list of available key types may also be obtained using
.Qq ssh -Q HostKeyAlgorithms .
@@ -987,14 +975,10 @@ ecdh-sha2-nistp521
.Bl -item -compact -offset indent
@@ -988,15 +981,6 @@ ecdh-sha2-nistp521
sntrup4591761x25519-sha512@tinyssh.org
.El
.Pp
@ -214,14 +397,41 @@ diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
-diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,
-diffie-hellman-group14-sha256
-.Ed
-.Pp
The list of available key exchange algorithms may also be obtained using
.Qq ssh -Q KexAlgorithms .
.It Cm ListenAddress
@@ -1065,21 +1049,26 @@ DEBUG and DEBUG1 are equivalent.
DEBUG2 and DEBUG3 each specify higher levels of debugging output.
Logging with a DEBUG level violates the privacy of users and is not recommended.
.It Cm MACs
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+.Pp
Specifies the available MAC (message authentication code) algorithms.
The MAC algorithm is used for data integrity protection.
Multiple algorithms must be comma-separated.
If the specified list begins with a
.Sq +
-character, then the specified algorithms will be appended to the default set
+character, then the specified algorithms will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified algorithms (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified algorithms will be placed at the head of the
-default set.
+built-in default set.
.Pp
The list of available key exchange algorithms may also be obtained using
.Qq ssh -Q KexAlgorithms .
@@ -1121,14 +1105,10 @@ umac-64-etm@openssh.com
The algorithms that contain
.Qq -etm
@@ -1122,15 +1111,6 @@ umac-64-etm@openssh.com
umac-128-etm@openssh.com
.El
.Pp
@ -233,17 +443,35 @@ diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
-umac-64@openssh.com,umac-128@openssh.com,
-hmac-sha2-256,hmac-sha2-512,hmac-sha1
-.Ed
-.Pp
The list of available MAC algorithms may also be obtained using
.Qq ssh -Q mac .
.It Cm Match
@@ -1480,36 +1460,25 @@ or equivalent.)
The default is
.Cm yes .
.It Cm PubkeyAcceptedKeyTypes
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
.Pp
The list of available MAC algorithms may also be obtained using
.Qq ssh -Q mac .
@@ -1492,22 +1472,10 @@ If the specified list begins with a
+.Pp
Specifies the key types that will be accepted for public key authentication
as a list of comma-separated patterns.
Alternately if the specified list begins with a
.Sq +
-character, then the specified key types will be appended to the default set
+character, then the specified key types will be appended to the built-in default set
instead of replacing them.
If the specified list begins with a
.Sq -
character, then the specified key types (including wildcards) will be removed
-from the default set instead of replacing them.
+from the built-in default set instead of replacing them.
If the specified list begins with a
.Sq ^
character, then the specified key types will be placed at the head of the
default set.
-default set.
-The default for this option is:
-.Bd -literal -offset 3n
-ecdsa-sha2-nistp256-cert-v01@openssh.com,
@ -260,10 +488,7 @@ diff -up openssh/sshd_config.5.crypto-policies openssh/sshd_config.5
-ssh-ed25519,sk-ssh-ed25519@openssh.com,
-rsa-sha2-512,rsa-sha2-256,ssh-rsa
-.Ed
+The default is handled system-wide by
+.Xr crypto-policies 7 .
+To see the defaults and how to modify this default, see manual page
+.Xr update-crypto-policies 8 .
+built-in default set.
.Pp
The list of available key types may also be obtained using
.Qq ssh -Q PubkeyAcceptedKeyTypes .