--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_require_otr/mod_require_otr.lua	Sat Feb 01 04:42:30 2014 +0500
@@ -0,0 +1,13 @@
+local st = require "util.stanza";
+local block_groupchat = module:get_option_boolean("otr_block_groupchat", false);
+
+function reject_plaintext_messages(event)
+    local body = event.stanza:get_child_text("body");
+    if body and body:sub(1,4) ~= "?OTR" or (not block_groupchat and event.stanza.attr.type == "groupchat") then
+        return event.origin.send(st.error_reply(event.stanza, "modify", "policy-violation", "OTR encryption is required for conversations on this server"));
+    end
+end
+
+module:hook("pre-message/bare", reject_plaintext_messages, 300);
+module:hook("pre-message/full", reject_plaintext_messages, 300);
+module:hook("pre-message/host", reject_plaintext_messages, 300);