Sanitize parameters on user edit page (fixes #289)

shard.lock

@@ -68,6 +68,10 @@ shards:
     git: https://github.com/luislavena/radix.git
     version: 0.4.1
 
+  sanitize:
+    git: https://github.com/hkalexling/sanitize.git
+    version: 0.1.0+git.commit.e09520e972d0d9b70b71bb003e6831f7c2c59dce
+
   sqlite3:
     git: https://github.com/crystal-lang/crystal-sqlite3.git
     version: 0.18.0

shard.yml

@@ -42,3 +42,5 @@ dependencies:
     branch: master
   mg:
    github: hkalexling/mg
+  sanitize:
+    github: hkalexling/sanitize

src/routes/admin.cr

@@ -1,3 +1,5 @@
+require "sanitize"
+
 struct AdminRouter
   def initialize
     get "/admin" do |env|
@@ -14,13 +16,13 @@ struct AdminRouter
     end
 
     get "/admin/user/edit" do |env|
-      username = env.params.query["username"]?
+      sanitizer = Sanitize::Policy::Text.new
+      username = env.params.query["username"]?.try { |s| sanitizer.process s }
       admin = env.params.query["admin"]?
       if admin
         admin = admin == "true"
       end
-      error = env.params.query["error"]?
-      current_user = get_username env
+      error = env.params.query["error"]?.try { |s| sanitizer.process s }
       new_user = username.nil? && admin.nil?
       layout "user-edit"
     end