Don't allow double compression.

diff --git a/plugins/mod_compression.lua b/plugins/mod_compression.lua
index 14265025546ac0bd4674a379bb8adcfb76cb1ea2..7e53a5e5d7ab629e4f1d2634dc0ff7e712a13800 100644 (file)
--- a/plugins/mod_compression.lua
+++ b/plugins/mod_compression.lua
@@ -37,6 +37,13 @@ module:add_event_hook("stream-features",
 -- TODO Support compression on S2S level too.
 module:add_handler({"c2s_unauthed", "c2s_authed"}, "compress", xmlns_compression_protocol,
                function(session, stanza)
+                       -- fail if we are already compressed
+                       if session.compressed then
+                               local error_st = st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("unsupported-method");
+                               session.send(error_st);
+                               session:log("warn", "Tried to establish another compression layer.");
+                       end
+                       
                        -- checking if the compression method is supported
                        local method = stanza:child_with_name("method")[1];
                        if method == "zlib" then
@@ -74,7 +81,7 @@ module:add_handler({"c2s_unauthed", "c2s_authed"}, "compress", xmlns_compression
                                                                text = compressed;
                                                                extra = st.stanza("failure", {xmlns="http://jabber.org/protocol/compress"}):tag("processing-failed");
                                                        });
-                                                       module:log("error", compressed);
+                                                       module:log("warn", compressed);
                                                        return;
                                                end
                                                old_send(compressed);
@@ -91,7 +98,7 @@ module:add_handler({"c2s_unauthed", "c2s_authed"}, "compress", xmlns_compression
                                                                        text = decompressed;
                                                                        extra = st.stanza("failure", {xmlns="http://jabber.org/protocol/compress"}):tag("processing-failed");
                                                                });
-                                                               module:log("error", decompressed);
+                                                               module:log("warn", decompressed);
                                                                return;
                                                        end
                                                        old_data(conn, decompressed);