From: David Disseldorp <ddiss@samba.org>
Date: Mon, 14 Oct 2013 11:53:22 +0000 (+0200)
Subject: param: disable print notify backchannel by default
X-Git-Url: http://git.samba.org/?p=mat%2Fsamba.git;a=commitdiff_plain;h=477e53a8cb5eda594cfe1cccb9890a4fcd586ff1

param: disable print notify backchannel by default

In handling RemoteFindFirstPrinterChangeNotifyEx requests, the spoolss
server can establish a "backchannel" connection to the print client, as
a mechanism for sending print notifications. This behaviour is governed
by the "print notify backchannel" smb.conf parameter.

This change sets "print notify backchannel" to "no" by default, which
sees Samba respond to RemoteFindFirstPrinterChangeNotifyEx requests with
WERR_SERVER_UNAVAILABLE. In recieving such a response, print clients can
fall back to polling for print queue changes.

Signed-off-by: David Disseldorp <ddiss@samba.org>
Reviewed-by: Günther Deschner <gd@samba.org>

Autobuild-User(master): Günther Deschner <gd@samba.org>
Autobuild-Date(master): Mon Oct 14 18:49:41 CEST 2013 on sn-devel-104
---

diff --git a/docs-xml/smbdotconf/printing/printnotifybackchannel.xml b/docs-xml/smbdotconf/printing/printnotifybackchannel.xml
index 4046322dd7..ce6a595fc9 100644
--- a/docs-xml/smbdotconf/printing/printnotifybackchannel.xml
+++ b/docs-xml/smbdotconf/printing/printnotifybackchannel.xml
@@ -8,12 +8,10 @@
 	the server to open a backchannel SMB connection to them. Due to
 	client firewall settings this can cause considerable timeouts
 	and will often fail, as there is no guarantee the client is even
-	running an SMB server. By setting this parameter to <constant>no</constant>
-	the Samba print server will not try to connect back to clients
-	and treat corresponding requests as if the connection back to
-	the client failed. The default setting of <constant>yes</constant>
-	causes smbd to attempt this connection.
+	running an SMB server. By default, the Samba print server will
+	not try to connect back to clients, and will treat corresponding
+	requests as if the connection back to the client failed.
 </para>
 </description>
-<value type="default">yes</value>
+<value type="default">no</value>
 </samba:parameter>
diff --git a/selftest/target/Samba3.pm b/selftest/target/Samba3.pm
index 0972457d92..fbbddcc926 100755
--- a/selftest/target/Samba3.pm
+++ b/selftest/target/Samba3.pm
@@ -998,6 +998,7 @@ sub provision($$$$$$)
 	queue pause command = $bindir_abs/vlp tdbfile=$lockdir/vlp.tdb queuepause %p
 	queue resume command = $bindir_abs/vlp tdbfile=$lockdir/vlp.tdb queueresume %p
 	lpq cache time = 0
+	print notify backchannel = yes
 
 	ncalrpc dir = $prefix_abs/ncalrpc
         resolv:host file = $dns_host_file
diff --git a/selftest/target/Samba4.pm b/selftest/target/Samba4.pm
index d7aa9c5bc1..646ac73061 100644
--- a/selftest/target/Samba4.pm
+++ b/selftest/target/Samba4.pm
@@ -1451,6 +1451,7 @@ sub provision_plugin_s4_dc($$)
 	queue pause command = $bindir_abs/vlp tdbfile=$lockdir/vlp.tdb queuepause %p
 	queue resume command = $bindir_abs/vlp tdbfile=$lockdir/vlp.tdb queueresume %p
 	lpq cache time = 0
+	print notify backchannel = yes
 
 ";
 
diff --git a/source3/param/loadparm.c b/source3/param/loadparm.c
index e702420124..3daebdb61c 100644
--- a/source3/param/loadparm.c
+++ b/source3/param/loadparm.c
@@ -218,7 +218,7 @@ static struct loadparm_service sDefault =
 	.bAdministrative_share = false,
 	.bGuest_ok = false,
 	.bPrint_ok = false,
-	.bPrintNotifyBackchannel = true,
+	.bPrintNotifyBackchannel = false,
 	.bMap_system = false,
 	.bMap_hidden = false,
 	.bMap_archive = true,