Support old SMB1 protocol in Tramp

* doc/misc/tramp.texi (Frequently Asked Questions):
Describe `tramp-smb-options'.

* lisp/net/tramp-smb.el (tramp-smb-conf): Fix docstring.
(tramp-smb-options): New defcustom.
(tramp-smb-handle-copy-directory, tramp-smb-handle-file-acl)
(tramp-smb-handle-set-file-acl, tramp-smb-maybe-open-connection):
Use it.

1 files changed, 17 insertions, 0 deletions

diff --git a/doc/misc/tramp.texi b/doc/misc/tramp.texi
index 4e39728a146..0b13c17dbcf 100644
--- a/doc/misc/tramp.texi
+++ b/doc/misc/tramp.texi
@@ -4144,6 +4144,23 @@ your proxy host.
 
 
 @item
+@value{tramp} does not connect to Samba or MS Windows hosts running
+SMB1 connection protocol.
+
+@vindex tramp-smb-options
+Recent versions of @command{smbclient} do not support old connection
+protocols by default.  In order to connect to such a host, add a
+respective option:
+
+@lisp
+(add-to-list 'tramp-smb-options "client min protocol=NT1")
+@end lisp
+
+@strong{Note} that using a deprecated connection protocol raises
+security problems, you should do it only if absolutely necessary.
+
+
+@item
 File name completion does not work with @value{tramp}
 
 @acronym{ANSI} escape sequences from the remote shell may cause errors