treewide: rework rollback/apply workflow

Rework the apply confirmation mechanism to be session agnostic in order to
circumvent cross domain restrictions which prevent the JS code from issuing
apply confirm requests in some cases, e.g. when changing the LAN IP.

Confirmation calls may now be done from unauthenticated pages, as long as a
matching confirmation token is sent along with the request.

The reasoning behind this is that there is little security impact in
confirming pending apply sessions, especially since those sessions can only
be initiated while being authenticated.

After this change, LuCI will now launch a confirmation process on every
rendered page when a rollback is pending. The confirmation will happen
regardless of whether the user is logged in or not, or if the current page
is a CBI form or static template.

A confirmation request now also requires a random one-time token which is
rendered along with the confirmation JavaScript code in order to succeed.

This token is not meant to provide security but to ensure that the confirm
was triggered from an interactive browser session and not some background
HTTP requests that happened to end up in the admin ui.

As a consequence, the different apply/confirm/rollback code paths in CBI
maps and the UCI change/revert pages have been consolidated into one common
implementation residing in the common global theme agnostic footer template.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

3 files changed, 24 insertions, 23 deletions

diff --git a/modules/luci-mod-admin-full/luasrc/controller/admin/uci.lua b/modules/luci-mod-admin-full/luasrc/controller/admin/uci.lua
index 9533ff5e6..1d955dd98 100644
--- a/modules/luci-mod-admin-full/luasrc/controller/admin/uci.lua
+++ b/modules/luci-mod-admin-full/luasrc/controller/admin/uci.lua
@@ -9,7 +9,7 @@ function index()
 		or table.concat(luci.dispatcher.context.request, "/")
 
 	entry({"admin", "uci"}, nil, _("Configuration"))
-	entry({"admin", "uci", "changes"}, call("action_changes"), _("Changes"), 40).query = {redir=redir}
+	entry({"admin", "uci", "changes"}, post_on({ trigger_apply = true }, "action_changes"), _("Changes"), 40).query = {redir=redir}
 	entry({"admin", "uci", "revert"}, post("action_revert"), _("Revert"), 30).query = {redir=redir}
 
 	local node
@@ -25,9 +25,9 @@ function index()
 	node.cors = true
 	node.sysauth_authenticator = authen
 
-	node = entry({"admin", "uci", "confirm"}, post("action_confirm"), nil)
+	node = entry({"admin", "uci", "confirm"}, call("action_confirm"), nil)
 	node.cors = true
-	node.sysauth_authenticator = authen
+	node.sysauth = false
 end
 
 
@@ -36,8 +36,9 @@ function action_changes()
 	local changes = uci:changes()
 
 	luci.template.render("admin_uci/changes", {
-		changes  = next(changes) and changes,
-		timeout  = timeout
+		changes       = next(changes) and changes,
+		timeout       = timeout,
+		trigger_apply = luci.http.formvalue("trigger_apply") and true or false
 	})
 end
 
@@ -52,7 +53,8 @@ function action_revert()
 	end
 
 	luci.template.render("admin_uci/revert", {
-		changes = next(changes) and changes
+		changes        = next(changes) and changes,
+		trigger_revert = true
 	})
 end
 
@@ -84,8 +86,13 @@ end
 
 function action_apply_rollback()
 	local uci = require "luci.model.uci"
-	local _, errstr = uci:apply(true)
-	ubus_state_to_http(errstr)
+	local token, errstr = uci:apply(true)
+	if token then
+		luci.http.prepare_content("application/json")
+		luci.http.write_json({ token = token })
+	else
+		ubus_state_to_http(errstr)
+	end
 end
 
 function action_apply_unchecked()
@@ -96,6 +103,7 @@ end
 
 function action_confirm()
 	local uci = require "luci.model.uci"
-	local _, errstr = uci:confirm()
+	local token = luci.http.formvalue("token")
+	local _, errstr = uci:confirm(token)
 	ubus_state_to_http(errstr)
 end
diff --git a/modules/luci-mod-admin-full/luasrc/view/admin_uci/changes.htm b/modules/luci-mod-admin-full/luasrc/view/admin_uci/changes.htm
index 628224475..43bd7c23f 100644
--- a/modules/luci-mod-admin-full/luasrc/view/admin_uci/changes.htm
+++ b/modules/luci-mod-admin-full/luasrc/view/admin_uci/changes.htm
@@ -8,11 +8,9 @@
 
 <%-
 	local node, redir_url = luci.dispatcher.lookup(luci.http.formvalue("redir"))
+	export("redirect", redir_url or url("admin/uci/changes"))
 
-	include("cbi/apply_widget")
 	include("admin_uci/changelog")
-
-	cbi_apply_widget(redir_url or url("admin/uci/changes"))
 -%>
 
 <h2 name="content"><%:Configuration%> / <%:Changes%></h2>
@@ -32,7 +30,11 @@
 	</form>
 	<% end %>
 
-	<input class="cbi-button cbi-button-save" type="button" id="apply_button" value="<%:Save & Apply%>" onclick="uci_apply(true); this.blur()" />
+	<form method="post" action="<%=url("admin/uci/changes")%>">
+		<input type="hidden" name="token" value="<%=token%>" />
+		<input type="hidden" name="redir" value="<%=pcdata(luci.http.formvalue("redir"))%>" />
+		<input class="cbi-button cbi-button-save" type="submit" name="trigger_apply" value="<%:Save & Apply%>" />
+	</form>
 	<form method="post" action="<%=url("admin/uci/revert")%>">
 		<input type="hidden" name="token" value="<%=token%>" />
 		<input type="hidden" name="redir" value="<%=pcdata(luci.http.formvalue("redir"))%>" />
diff --git a/modules/luci-mod-admin-full/luasrc/view/admin_uci/revert.htm b/modules/luci-mod-admin-full/luasrc/view/admin_uci/revert.htm
index ff23d568d..d8fd3de01 100644
--- a/modules/luci-mod-admin-full/luasrc/view/admin_uci/revert.htm
+++ b/modules/luci-mod-admin-full/luasrc/view/admin_uci/revert.htm
@@ -8,11 +8,9 @@
 
 <%-
 	local node, redir_url = luci.dispatcher.lookup(luci.http.formvalue("redir"))
+	export("redirect", redir_url or url("admin/uci/changes"))
 
-	include("cbi/apply_widget")
 	include("admin_uci/changelog")
-
-	cbi_apply_widget(redir_url or url("admin/uci/revert"))
 -%>
 
 <h2 name="content"><%:Configuration%> / <%:Revert%></h2>
@@ -24,13 +22,6 @@
 	<p><strong><%:There are no pending changes to revert!%></strong></p>
 <% end %>
 
-<div class="alert-message" id="cbi_apply_status" style="display:none"></div>
-<script type="text/javascript">
-	document.addEventListener("DOMContentLoaded", function() {
-		uci_revert();
-	});
-</script>
-
 <% if redir_url then %>
 	<div class="cbi-page-actions">
 		<form class="inline" method="get" action="<%=luci.util.pcdata(redir_url)%>">