security: add support for main action

This commit adds support for the change in elasticsearch where the `/` rest
endpoint now delegates to an action and can be authorized.

Original commit: elastic/x-pack-elasticsearch@8ef38ce50f

elasticsearch/qa/smoke-test-graph-with-shield/roles.yml

@@ -9,6 +9,7 @@ admin:
 graph_explorer:
   cluster:
     - cluster:monitor/health
+    - cluster:monitor/main
   indices:
     - names: '*'
       privileges:
@@ -21,6 +22,7 @@ graph_explorer:
 no_graph_explorer:
   cluster:
     - cluster:monitor/health
+    - cluster:monitor/main
   indices:
     - names: '*'
       privileges:

elasticsearch/qa/smoke-test-watcher-with-shield/roles.yml

@@ -30,4 +30,5 @@ crappy_role:
     - cluster:monitor/nodes/info
     - cluster:monitor/health
     - cluster:monitor/nodes/liveness
+    - cluster:monitor/main
 

elasticsearch/x-pack/shield/config/x-pack/roles.yml

@@ -23,7 +23,7 @@ monitoring_user:
 # Marvel remote agent role. Assign to the agent user on the remote marvel cluster
 # to which the marvel agent will export all its data
 remote_monitoring_agent:
-  cluster: [ "manage_index_templates" ]
+  cluster: [ "manage_index_templates", "monitor" ]
   indices:
     - names:
         - '.marvel-es-*'

elasticsearch/x-pack/shield/src/test/resources/org/elasticsearch/transport/actions

@@ -13,6 +13,7 @@ cluster:admin/snapshot/status
 cluster:admin/tasks/cancel
 cluster:monitor/allocation/explain
 cluster:monitor/health
+cluster:monitor/main
 cluster:monitor/nodes/hot_threads
 cluster:monitor/nodes/info
 cluster:monitor/nodes/stats

elasticsearch/x-pack/shield/src/test/resources/org/elasticsearch/transport/handlers

@@ -3,6 +3,7 @@ cluster:admin/snapshot/status[nodes]
 cluster:admin/snapshot/status[nodes][n]
 cluster:admin/tasks/cancel[n]
 cluster:monitor/allocation/explain
+cluster:monitor/main
 cluster:monitor/nodes/hot_threads[n]
 cluster:monitor/nodes/info[n]
 cluster:monitor/nodes/liveness