Fix ActionDispatch::Static to serve files with unencoded PCHAR

RFC 3986[1] allows sub-delim characters in path segments unencoded,
however Rack::File requires them to be encoded so we use URI's
unescape method to leave them alone and then escape them again.

Also since the path gets passed to Dir[] we need to escape any glob
characters in the path.

[1]: http://www.ietf.org/rfc/rfc3986.txt

actionpack/lib/action_dispatch/middleware/static.rb

@@ -11,14 +11,14 @@ def initialize(root, cache_control)
     def match?(path)
       path = path.dup
 
-      full_path = path.empty? ? @root : File.join(@root, ::Rack::Utils.unescape(path))
+      full_path = path.empty? ? @root : File.join(@root, escape_glob_chars(unescape_path(path)))
       paths = "#{full_path}#{ext}"
 
       matches = Dir[paths]
       match = matches.detect { |m| File.file?(m) }
       if match
         match.sub!(@compiled_root, '')
-        match
+        ::Rack::Utils.escape(match)
       end
     end
 
@@ -32,6 +32,14 @@ def ext
         "{,#{ext},/index#{ext}}"
       end
     end
+
+    def unescape_path(path)
+      URI.parser.unescape(path)
+    end
+
+    def escape_glob_chars(path)
+      path.gsub(/(\*|\?|\[|\]|\{|\})/, "\\\\\\1")
+    end
   end
 
   class Static

actionpack/test/dispatch/static_test.rb

@@ -30,6 +30,34 @@ def test_serves_static_index_file_in_directory
     assert_html "/foo/index.html", get("/foo")
   end
 
+  def test_serves_static_file_with_encoded_pchar
+    assert_html "/foo/foo!bar.html", get("/foo/foo%21bar.html")
+    assert_html "/foo/foo$bar.html", get("/foo/foo%24bar.html")
+    assert_html "/foo/foo&bar.html", get("/foo/foo%26bar.html")
+    assert_html "/foo/foo'bar.html", get("/foo/foo%27bar.html")
+    assert_html "/foo/foo(bar).html", get("/foo/foo%28bar%29.html")
+    assert_html "/foo/foo*bar.html", get("/foo/foo%2Abar.html")
+    assert_html "/foo/foo+bar.html", get("/foo/foo%2Bbar.html")
+    assert_html "/foo/foo,bar.html", get("/foo/foo%2Cbar.html")
+    assert_html "/foo/foo;bar.html", get("/foo/foo%3Bbar.html")
+    assert_html "/foo/foo:bar.html", get("/foo/foo%3Abar.html")
+    assert_html "/foo/foo@bar.html", get("/foo/foo%40bar.html")
+  end
+
+  def test_serves_static_file_with_unencoded_pchar
+    assert_html "/foo/foo!bar.html", get("/foo/foo!bar.html")
+    assert_html "/foo/foo$bar.html", get("/foo/foo$bar.html")
+    assert_html "/foo/foo&bar.html", get("/foo/foo&bar.html")
+    assert_html "/foo/foo'bar.html", get("/foo/foo'bar.html")
+    assert_html "/foo/foo(bar).html", get("/foo/foo(bar).html")
+    assert_html "/foo/foo*bar.html", get("/foo/foo*bar.html")
+    assert_html "/foo/foo+bar.html", get("/foo/foo+bar.html")
+    assert_html "/foo/foo,bar.html", get("/foo/foo,bar.html")
+    assert_html "/foo/foo;bar.html", get("/foo/foo;bar.html")
+    assert_html "/foo/foo:bar.html", get("/foo/foo:bar.html")
+    assert_html "/foo/foo@bar.html", get("/foo/foo@bar.html")
+  end
+
   private
 
     def assert_html(body, response)

actionpack/test/fixtures/public/foo/foo!bar.html

@@ -0,0 +1 @@
+/foo/foo!bar.html

actionpack/test/fixtures/public/foo/foo$bar.html

@@ -0,0 +1 @@
+/foo/foo$bar.html

actionpack/test/fixtures/public/foo/foo&bar.html

@@ -0,0 +1 @@
+/foo/foo&bar.html

actionpack/test/fixtures/public/foo/foo'bar.html

@@ -0,0 +1 @@
+/foo/foo'bar.html

actionpack/test/fixtures/public/foo/foo(bar).html

@@ -0,0 +1 @@
+/foo/foo(bar).html

actionpack/test/fixtures/public/foo/foo*bar.html

@@ -0,0 +1 @@
+/foo/foo*bar.html

actionpack/test/fixtures/public/foo/foo+bar.html

@@ -0,0 +1 @@
+/foo/foo+bar.html

actionpack/test/fixtures/public/foo/foo,bar.html

@@ -0,0 +1 @@
+/foo/foo,bar.html

actionpack/test/fixtures/public/foo/foo:bar.html

@@ -0,0 +1 @@
+/foo/foo:bar.html

actionpack/test/fixtures/public/foo/foo;bar.html

@@ -0,0 +1 @@
+/foo/foo;bar.html

actionpack/test/fixtures/public/foo/foo=bar.html

@@ -0,0 +1 @@
+/foo/foo=bar.html

actionpack/test/fixtures/public/foo/foo@bar.html

@@ -0,0 +1 @@
+/foo/foo@bar.html