Merge branch...

Merge branch 'ee-1159-allow-permission-check-bypass-in-approve-access-request-service-ee' into 'master'

Don't pass a current user to Member#add_user in LDAP group sync

See the individual commits for explanation of the changes.

This is part of the fix for gitlab-org/gitlab-ee#1159.

CE backport for the change in `Members::ApproveAccessRequestService` is at gitlab-org/gitlab-ce!7168.
/cc @stanhu

See merge request !830

app/models/member.rb

@@ -111,7 +111,7 @@ class Member < ActiveRecord::Base
           current_user,
           id: member.id,
           access_level: access_level
-        ).execute
+        ).execute(force: ldap)
       else
         member.save
       end

app/services/members/approve_access_request_service.rb

@@ -4,17 +4,25 @@ module Members
 
     attr_accessor :source
 
+    # source - The source object that respond to `#requesters` (i.g. project or group)
+    # current_user - The user that performs the access request approval
+    # params - A hash of parameters
+    #   :user_id - User ID used to retrieve the access requester
+    #   :id - Member ID used to retrieve the access requester
+    #   :access_level - Optional access level set when the request is accepted
     def initialize(source, current_user, params = {})
       @source = source
       @current_user = current_user
-      @params = params
+      @params = params.slice(:user_id, :id, :access_level)
     end
 
-    def execute
+    # opts - A hash of options
+    #   :force - Bypass permission check: current_user can be nil in that case
+    def execute(opts = {})
       condition = params[:user_id] ? { user_id: params[:user_id] } : { id: params[:id] }
       access_requester = source.requesters.find_by!(condition)
 
-      raise Gitlab::Access::AccessDeniedError unless can_update_access_requester?(access_requester)
+      raise Gitlab::Access::AccessDeniedError unless can_update_access_requester?(access_requester, opts)
 
       access_requester.access_level = params[:access_level] if params[:access_level]
       access_requester.accept_request
@@ -24,8 +32,11 @@ module Members
 
     private
 
-    def can_update_access_requester?(access_requester)
-      access_requester && can?(current_user, action_member_permission(:update, access_requester), access_requester)
+    def can_update_access_requester?(access_requester, opts = {})
+      access_requester && (
+        opts[:force] ||
+        can?(current_user, action_member_permission(:update, access_requester), access_requester)
+      )
     end
   end
 end

lib/ee/gitlab/ldap/sync/group.rb

@@ -99,13 +99,6 @@ module EE
           def update_existing_group_membership(group, access_levels)
             logger.debug { "Updating existing membership for '#{group.name}' group" }
 
-            # Access requesters must be approved by a group owner so we take the
-            # first group owner and pass it as `current_user` to `#add_or_update_user_membership`.
-            # For users that are not access requesters, it doesn't matter if
-            # `current_user` is `nil` because the permissions to update users are
-            # not enforced in `Member.add_user`!
-            added_by = group.members.owners.first.try(:user)
-
             select_and_preload_group_members(group).each do |member|
               user = member.user
               identity = user.identities.select(:id, :extern_uid)
@@ -147,8 +140,7 @@ module EE
                 add_or_update_user_membership(
                   user,
                   group,
-                  desired_access,
-                  current_user: added_by
+                  desired_access
                 )
               elsif group.last_owner?(user)
                 warn_cannot_remove_last_owner(user, group)
@@ -161,13 +153,6 @@ module EE
           def add_new_members(group, access_levels)
             logger.debug { "Adding new members to '#{group.name}' group" }
 
-            # Access requesters must be approved by a group owner so we take the
-            # first group owner and pass it as `current_user` to `#add_or_update_user_membership`.
-            # For users that are not access requesters, it doesn't matter if
-            # `current_user` is `nil` because the permissions to update users are
-            # not enforced in `Member.add_user`!
-            added_by = group.members.owners.first.try(:user)
-
             access_levels.each do |member_dn, access_level|
               user = ::Gitlab::LDAP::User.find_by_uid_and_provider(member_dn, provider)
 
@@ -175,8 +160,7 @@ module EE
                 add_or_update_user_membership(
                   user,
                   group,
-                  access_level,
-                  current_user: added_by
+                  access_level
                 )
               else
                 logger.debug do

spec/lib/ee/gitlab/ldap/sync/group_spec.rb

@@ -4,10 +4,13 @@ describe EE::Gitlab::LDAP::Sync::Group, lib: true do
   include LdapHelpers
 
   let(:adapter) { ldap_adapter }
-  let(:sync_group) { described_class.new(group, proxy(adapter)) }
   let(:user) { create(:user) }
 
   before do
+    # We need to actually activate the LDAP config otherwise `Group#ldap_synced?`
+    # will always be false!
+    allow(Gitlab.config.ldap).to receive_messages(enabled: true)
+
     create(:identity, user: user, extern_uid: user_dn(user.username))
 
     stub_ldap_config(active_directory: false)
@@ -113,6 +116,9 @@ describe EE::Gitlab::LDAP::Sync::Group, lib: true do
 
   describe '#update_permissions' do
     before do
+      # Safe-check because some permissions are removed when `Group#ldap_synced?`
+      # is true (e.g. in `GroupPolicy`).
+      expect(group).to be_ldap_synced
       group.start_ldap_sync
     end
     after do
@@ -124,6 +130,7 @@ describe EE::Gitlab::LDAP::Sync::Group, lib: true do
              cn: 'ldap_group1',
              group_access: ::Gitlab::Access::DEVELOPER)
     end
+    let(:sync_group) { described_class.new(group, proxy(adapter)) }
 
     context 'with all functionality against one LDAP group type' do
       context 'with basic add/update actions' do

spec/services/members/approve_access_request_service_spec.rb

@@ -5,36 +5,37 @@ describe Members::ApproveAccessRequestService, services: true do
   let(:access_requester) { create(:user) }
   let(:project) { create(:project, :public) }
   let(:group) { create(:group, :public) }
+  let(:opts) { {} }
 
   shared_examples 'a service raising ActiveRecord::RecordNotFound' do
     it 'raises ActiveRecord::RecordNotFound' do
-      expect { described_class.new(source, user, params).execute }.to raise_error(ActiveRecord::RecordNotFound)
+      expect { described_class.new(source, user, params).execute(opts) }.to raise_error(ActiveRecord::RecordNotFound)
     end
   end
 
   shared_examples 'a service raising Gitlab::Access::AccessDeniedError' do
     it 'raises Gitlab::Access::AccessDeniedError' do
-      expect { described_class.new(source, user, params).execute }.to raise_error(Gitlab::Access::AccessDeniedError)
+      expect { described_class.new(source, user, params).execute(opts) }.to raise_error(Gitlab::Access::AccessDeniedError)
     end
   end
 
   shared_examples 'a service approving an access request' do
     it 'succeeds' do
-      expect { described_class.new(source, user, params).execute }.to change { source.requesters.count }.by(-1)
+      expect { described_class.new(source, user, params).execute(opts) }.to change { source.requesters.count }.by(-1)
     end
 
     it 'returns a <Source>Member' do
-      member = described_class.new(source, user, params).execute
+      member = described_class.new(source, user, params).execute(opts)
 
       expect(member).to be_a "#{source.class}Member".constantize
       expect(member.requested_at).to be_nil
     end
 
     context 'with a custom access level' do
-      let(:params) { { user_id: access_requester.id, access_level: Gitlab::Access::MASTER } }
+      let(:params2) { params.merge(user_id: access_requester.id, access_level: Gitlab::Access::MASTER) }
 
       it 'returns a ProjectMember with the custom access level' do
-        member = described_class.new(source, user, params).execute
+        member = described_class.new(source, user, params2).execute(opts)
 
         expect(member.access_level).to eq Gitlab::Access::MASTER
       end
@@ -60,6 +61,56 @@ describe Members::ApproveAccessRequestService, services: true do
     end
     let(:params) { { user_id: access_requester.id } }
 
+    context 'when current user is nil' do
+      let(:user) { nil }
+
+      context 'and :force option is not given' do
+        it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
+          let(:source) { project }
+        end
+
+        it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
+          let(:source) { group }
+        end
+      end
+
+      context 'and :force option is false' do
+        let(:opts) { { force: false } }
+
+        it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
+          let(:source) { project }
+        end
+
+        it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
+          let(:source) { group }
+        end
+      end
+
+      context 'and :force option is true' do
+        let(:opts) { { force: true } }
+
+        it_behaves_like 'a service approving an access request' do
+          let(:source) { project }
+        end
+
+        it_behaves_like 'a service approving an access request' do
+          let(:source) { group }
+        end
+      end
+
+      context 'and :force param is true' do
+        let(:params) { { user_id: access_requester.id, force: true } }
+
+        it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
+          let(:source) { project }
+        end
+
+        it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
+          let(:source) { group }
+        end
+      end
+    end
+
     context 'when current user cannot approve access request to the project' do
       it_behaves_like 'a service raising Gitlab::Access::AccessDeniedError' do
         let(:source) { project }