util.pposix: Compatibility with Solaris systems (thanks Filip)

[prosody.git] / plugins / mod_compression.lua

diff --git a/plugins/mod_compression.lua b/plugins/mod_compression.lua
index 4b8988339263c279089340b783fb292709007b1b..f1cae7378e23019ae8b6063eb4a8aa9a6582cda7 100644 (file)
--- a/plugins/mod_compression.lua
+++ b/plugins/mod_compression.lua
@@ -6,26 +6,113 @@
 --
 
 local st = require "util.stanza";
-local print = print
+local zlib = require "zlib";
+local pcall = pcall;
 
 local xmlns_compression_feature = "http://jabber.org/features/compress"
 local xmlns_compression_protocol = "http://jabber.org/protocol/compress"
 local compression_stream_feature = st.stanza("compression", {xmlns=xmlns_compression_feature}):tag("method"):text("zlib"):up();
 
+local compression_level = module:get_option("compression_level");
 
-module:add_event_hook("stream-features", 
+-- if not defined assume admin wants best compression
+if compression_level == nil then compression_level = 9 end;
+
+compression_level = tonumber(compression_level);
+if not compression_level or compression_level < 1 or compression_level > 9 then
+       module:log("warn", "Invalid compression level in config: %s", tostring(compression_level));
+       module:log("warn", "Module loading aborted. Compression won't be available.");
+       return;
+end
+
+module:add_event_hook("stream-features",
                function (session, features)
-                       features:add_child(compression_stream_feature);
+                       if not session.compressed then
+                               -- FIXME only advertise compression support when TLS layer has no compression enabled
+                               features:add_child(compression_stream_feature);
+                       end
                end
 );
 
-module:add_handler("c2s_unauthed", "compress", xmlns_compression_protocol, 
+-- TODO Support compression on S2S level too.
+module:add_handler({"c2s_unauthed", "c2s"}, "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
                                session.log("info", method.." compression selected.");
                                session.send(st.stanza("compressed", {xmlns=xmlns_compression_protocol}));
+                               session:reset_stream();
+                               
+                               -- create deflate and inflate streams
+                               local status, deflate_stream = pcall(zlib.deflate, compression_level);
+                               if status == false then
+                                       local error_st = st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("setup-failed");
+                                       session.send(error_st);
+                                       session:log("error", "Failed to create zlib.deflate filter.");
+                                       module:log("error", deflate_stream);
+                                       return
+                               end
+                               
+                               local status, inflate_stream = pcall(zlib.inflate);
+                               if status == false then
+                                       local error_st = st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("setup-failed");
+                                       session.send(error_st);
+                                       session:log("error", "Failed to create zlib.deflate filter.");
+                                       module:log("error", inflate_stream);
+                                       return
+                               end
+                               
+                               -- setup compression for session.w
+                               local old_send = session.send;
+                               
+                               session.send = function(t)
+                                               local status, compressed, eof = pcall(deflate_stream, tostring(t), 'sync');
+                                               if status == false then
+                                                       session:close({
+                                                               condition = "undefined-condition";
+                                                               text = compressed;
+                                                               extra = st.stanza("failure", {xmlns="http://jabber.org/protocol/compress"}):tag("processing-failed");
+                                                       });
+                                                       module:log("warn", compressed);
+                                                       return;
+                                               end
+                                               old_send(compressed);
+                                       end;
+                                       
+                               -- setup decompression for session.data
+                               local function setup_decompression(session)
+                                       local old_data = session.data
+                                       session.data = function(conn, data)
+                                                       local status, decompressed, eof = pcall(inflate_stream, data);
+                                                       if status == false then
+                                                               session:close({
+                                                                       condition = "undefined-condition";
+                                                                       text = decompressed;
+                                                                       extra = st.stanza("failure", {xmlns="http://jabber.org/protocol/compress"}):tag("processing-failed");
+                                                               });
+                                                               module:log("warn", decompressed);
+                                                               return;
+                                                       end
+                                                       old_data(conn, decompressed);
+                                               end;
+                               end
+                               setup_decompression(session);
+                               
+                               local session_reset_stream = session.reset_stream;
+                               session.reset_stream = function(session)
+                                               session_reset_stream(session);
+                                               setup_decompression(session);
+                                               return true;
+                                       end;
+                               session.compressed = true;
                        else
                                session.log("info", method.." compression selected. But we don't support it.");
                                local error_st = st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("unsupported-method");