SECURITY: Add more restrictions on invite emails

They could be filtered and returned in some circumstances where they
shouldn't have been.

app/controllers/users_controller.rb

@@ -286,8 +286,13 @@ class UsersController < ApplicationController
       Invite.find_redeemed_invites_from(inviter, offset)
     end
 
-    invites = invites.filter_by(params[:search])
-    render_json_dump invites: serialize_data(invites.to_a, InviteSerializer),
+    show_emails = guardian.can_see_invite_emails?(inviter)
+    if params[:search].present?
+      filter_sql = '(LOWER(users.username) LIKE :filter)'
+      filter_sql = '(LOWER(invites.email) LIKE :filter) or (LOWER(users.username) LIKE :filter)' if show_emails
+      invites = invites.where(filter_sql, filter: "%#{params[:search].downcase}%")
+    end
+    render_json_dump invites: serialize_data(invites.to_a, InviteSerializer, show_emails: show_emails),
                      can_see_invite_details: guardian.can_see_invite_details?(inviter)
   end
 

app/serializers/invite_serializer.rb

@@ -5,7 +5,7 @@ class InviteSerializer < ApplicationSerializer
   attributes :email, :updated_at, :redeemed_at, :expired, :user
 
   def include_email?
-    !object.redeemed?
+    options[:show_emails] && !object.redeemed?
   end
 
   def expired

lib/guardian.rb

@@ -331,6 +331,10 @@ class Guardian
     is_me?(user)
   end
 
+  def can_see_invite_emails?(user)
+    is_staff? || is_me?(user)
+  end
+
   def can_invite_to_forum?(groups = nil)
     authenticated? &&
     (SiteSetting.max_invites_per_day.to_i > 0 || is_staff?) &&

spec/requests/users_controller_spec.rb

@@ -1466,23 +1466,13 @@ describe UsersController do
       expect(response.status).to eq(200)
     end
 
-    it 'filters by email' do
+    it 'filters by all if viewing self' do
       inviter = Fabricate(:user, trust_level: 2)
       sign_in(inviter)
 
       invitee = Fabricate(:user)
-      Fabricate(
-        :invite,
-        email: 'billybob@example.com',
-        invited_by: inviter,
-        user: invitee
-      )
-      Fabricate(
-        :invite,
-        email: 'jimtom@example.com',
-        invited_by: inviter,
-        user: invitee
-      )
+      Fabricate(:invite, email: 'billybob@example.com', invited_by: inviter, user: invitee)
+      Fabricate(:invite, email: 'jimtom@example.com', invited_by: inviter, user: invitee)
 
       get "/u/#{inviter.username}/invited.json", params: { search: 'billybob' }
       expect(response.status).to eq(200)
@@ -1490,31 +1480,51 @@ describe UsersController do
       invites = JSON.parse(response.body)['invites']
       expect(invites.size).to eq(1)
       expect(invites.first).to include('email' => 'billybob@example.com')
+
+      get "/u/#{inviter.username}/invited.json", params: { search: invitee.username }
+      expect(response.status).to eq(200)
+
+      invites = JSON.parse(response.body)['invites']
+      expect(invites.size).to eq(2)
+      expect(invites[0]['email']).to be_present
     end
 
-    it 'filters by username' do
+    it "doesn't filter by email if another regular user" do
       inviter = Fabricate(:user, trust_level: 2)
-      sign_in(inviter)
+      sign_in(Fabricate(:user, trust_level: 2))
 
-      invitee = Fabricate(:user, username: 'billybob')
-      _invite = Fabricate(
-        :invite,
-        invited_by: inviter,
-        email: 'billybob@example.com',
-        user: invitee
-      )
-      Fabricate(
-        :invite,
-        invited_by: inviter,
-        user: Fabricate(:user, username: 'jimtom')
-      )
+      invitee = Fabricate(:user)
+      Fabricate(:invite, email: 'billybob@example.com', invited_by: inviter, user: invitee)
+      Fabricate(:invite, email: 'jimtom@example.com', invited_by: inviter, user: invitee)
+
+      get "/u/#{inviter.username}/invited.json", params: { search: 'billybob' }
+      expect(response.status).to eq(200)
+
+      invites = JSON.parse(response.body)['invites']
+      expect(invites.size).to eq(0)
+
+      get "/u/#{inviter.username}/invited.json", params: { search: invitee.username }
+      expect(response.status).to eq(200)
+
+      invites = JSON.parse(response.body)['invites']
+      expect(invites.size).to eq(2)
+      expect(invites[0]['email']).to be_blank
+    end
+
+    it "filters by email if staff" do
+      inviter = Fabricate(:user, trust_level: 2)
+      sign_in(Fabricate(:moderator))
+
+      invitee = Fabricate(:user)
+      Fabricate(:invite, email: 'billybob@example.com', invited_by: inviter, user: invitee)
+      Fabricate(:invite, email: 'jimtom@example.com', invited_by: inviter, user: invitee)
 
       get "/u/#{inviter.username}/invited.json", params: { search: 'billybob' }
       expect(response.status).to eq(200)
 
       invites = JSON.parse(response.body)['invites']
       expect(invites.size).to eq(1)
-      expect(invites.first).to include('email' => 'billybob@example.com')
+      expect(invites[0]['email']).to be_present
     end
 
     context 'with guest' do
@@ -1581,7 +1591,7 @@ describe UsersController do
 
       context 'with redeemed invites' do
         it 'returns invites' do
-          sign_in(Fabricate(:user, trust_level: 2))
+          sign_in(Fabricate(:moderator))
           inviter = Fabricate(:user)
           invitee = Fabricate(:user)
           invite = Fabricate(:invite, invited_by: inviter, user: invitee)