luci-base: handle bodies of non-POST requests as well

Decode the HTTP message bodies of any request carrying a Content-Length
header, not just those in POST requests.

This allows handling parameters in other methods, OPTIONS in particular.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

modules/luci-base/luasrc/http.lua

@@ -486,26 +486,22 @@ end
 -- handled then the whole message body will be stored unaltered as "content"
 -- property within the given message object.
 function parse_message_body(src, msg, filecb)
+	if msg.env.CONTENT_LENGTH or msg.env.REQUEST_METHOD == "POST" then
 		local ctype = lhttp.header_attribute(msg.env.CONTENT_TYPE, nil)
 
 		-- Is it multipart/mime ?
-	if msg.env.REQUEST_METHOD == "POST" and
+		if ctype == "multipart/form-data" then
-	   ctype == "multipart/form-data"
-	then
 			return mimedecode_message_body(src, msg, filecb)
 
 		-- Is it application/x-www-form-urlencoded ?
-	elseif msg.env.REQUEST_METHOD == "POST" and
+		elseif ctype == "application/x-www-form-urlencoded" then
-	       ctype == "application/x-www-form-urlencoded"
-	then
 			return urldecode_message_body(src, msg)
 
+		end
 
 		-- Unhandled encoding
 		-- If a file callback is given then feed it chunk by chunk, else
 		-- store whole buffer in message.content
-	else
-
 		local sink
 
 		-- If we have a file callback then feed it
@@ -553,4 +549,6 @@ function parse_message_body(src, msg, filecb)
 
 		return true
 	end
+
+	return false
 end