Doc update wrt Tramp support of SSH security keys

* doc/misc/tramp.texi (Frequently Asked Questions): Speak about
SSH security keys.
(GVFS-based methods, Predefined connection information)
(Remote shell setup): Fix typo.

* etc/NEWS: Precise Tramp's support for SSH security keys.  Fix typos.

2 files changed, 25 insertions, 13 deletions

diff --git a/doc/misc/tramp.texi b/doc/misc/tramp.texi
index 5672648b42f..38c20de62a2 100644
--- a/doc/misc/tramp.texi
+++ b/doc/misc/tramp.texi
@@ -1290,7 +1290,7 @@ they are added here for the benefit of @ref{Archive file names}.
 
 If you want to use @acronym{GVFS}-based @option{ftp} or @option{smb}
 methods, you must add them to @code{tramp-gvfs-methods}, and you must
-disable the corresponding Tramp package by setting
+disable the corresponding @value{tramp} package by setting
 @code{tramp-ftp-method} or @code{tramp-smb-method} to @code{nil},
 respectively:
 
@@ -2122,9 +2122,9 @@ to construct these lists.
 
 @item @t{"remote-shell"}
 
-This property tells Tramp which remote shell to apply on the remote
-host.  It is used in all connection methods of @file{tramp-sh.el}.
-The default value is @t{"/bin/sh"}.
+This property tells @value{tramp} which remote shell to apply on the
+remote host.  It is used in all connection methods of
+@file{tramp-sh.el}.  The default value is @t{"/bin/sh"}.
 
 @item @t{"remote-shell-login"}
 
@@ -2310,9 +2310,9 @@ trouble with the shell prompt due to set zle options will be avoided.
 For @command{bash}, loading @file{~/.editrc} or @file{~/.inputrc} is
 suppressed.
 
-Similar problems can happen with the local shell Tramp uses to create
-a process.  By default, it uses the command @command{/bin/sh} for
-this, which could also be a link to another shell.  In order to
+Similar problems can happen with the local shell @value{tramp} uses to
+create a process.  By default, it uses the command @command{/bin/sh}
+for this, which could also be a link to another shell.  In order to
 overwrite this, you might apply
 
 @vindex tramp-encoding-shell
@@ -4578,6 +4578,16 @@ supported on your proxy host.
 
 
 @item
+Does @value{tramp} support @acronym{SSH} security keys?
+
+Yes.  @command{OpenSSH} has added support for @acronym{FIDO} hardware
+devices via special key types @option{*-sk}.  @value{tramp} supports
+the additional handshaking messages for them.  This requires at least
+@command{OpenSSH} 8.2, and a @acronym{FIDO} @acronym{U2F} compatible
+security key, like yubikey, solokey, or nitrokey.
+
+
+@item
 @value{tramp} does not connect to Samba or MS Windows hosts running
 SMB1 connection protocol
 
diff --git a/etc/NEWS b/etc/NEWS
index 674152c8c8a..378a32e2d35 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -798,7 +798,7 @@ The method of highlighting is specified by the user options
 'next-error-highlight' and 'next-error-highlight-no-select'.
 
 ---
-*** A fringe arrow in the '*Occur*' buffer indicates the selected match.
+*** A fringe arrow in the "*Occur*" buffer indicates the selected match.
 
 ---
 *** Occur mode may use a different type for 'occur-target' property values.
@@ -818,7 +818,7 @@ It is now defined as a generalized variable that can be used with
 
 ---
 *** 'form' in '(eql form)' specializers in 'cl-defmethod' is now evaluated.
-This corresponds to the behaviour of defmethod in Common Lisp Object System.
+This corresponds to the behavior of defmethod in Common Lisp Object System.
 For compatibility, '(eql SYMBOL)' does not evaluate SYMBOL, for now.
 
 ** New minor mode 'cl-font-lock-built-in-mode' for 'lisp-mode'.
@@ -1551,8 +1551,10 @@ like cell phones, tablets or cameras.
 *** New connection method "sshfs", which allows accessing remote files
 via a file system mounted with 'sshfs'.
 
----
-*** Tramp supports authentication via yubikey now.
++++
+*** Tramp supports SSH authentication via a hardware security key now.
+This requires at least OpenSSH 8.2, and a FIDO U2F compatible
+security key, like yubikey, solokey, or nitrokey.
 
 +++
 *** Trashed remote files are moved to the local trash directory.
@@ -1981,7 +1983,7 @@ to prevent aliasing and other unwanted effects.  The new image
 property ':transform-smoothing' can be set to t to force smoothing
 and nil to disable smoothing.
 
-The default behaviour of smoothing on down-scaling and not smoothing
+The default behavior of smoothing on down-scaling and not smoothing
 on up-scaling remains unchanged.
 
 +++
@@ -2981,7 +2983,7 @@ command, which updates the syntax highlighting in the current buffer.
 
 ** In 'f90-mode', the backslash character ('\') no longer escapes.
 For about a decade, the backslash character has no longer had a
-special escape syntax in Fortran F90.  To get the old behaviour back,
+special escape syntax in Fortran F90.  To get the old behavior back,
 say something like:
 
     (modify-syntax-entry ?\\ "\\" f90-mode-syntax-table)