-- Prosody IM
--- Copyright (C) 2009 Tobias Markmann
---
+-- Copyright (C) 2009-2012 Tobias Markmann
+--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--
local st = require "util.stanza";
local zlib = require "zlib";
local pcall = pcall;
+local tostring = tostring;
+
local xmlns_compression_feature = "http://jabber.org/features/compress"
local xmlns_compression_protocol = "http://jabber.org/protocol/compress"
local xmlns_stream = "http://etherx.jabber.org/streams";
local compression_stream_feature = st.stanza("compression", {xmlns=xmlns_compression_feature}):tag("method"):text("zlib"):up();
+local add_filter = require "util.filters".add_filter;
-local compression_level = module:get_option("compression_level");
--- if not defined assume admin wants best compression
-if compression_level == nil then compression_level = 9 end;
-
+local compression_level = module:get_option_number("compression_level", 7);
-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)
- 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:hook("stream-features", function(event)
+ local origin, features = event.origin, event.features;
+ if not origin.compressed and origin.type == "c2s" then
+ features:add_child(compression_stream_feature);
+ end
+end);
-module:hook("s2s-stream-features",
- function (data)
- local session, features = data.session, data.features;
- -- FIXME only advertise compression support when TLS layer has no compression enabled
- features:add_child(compression_stream_feature);
- end
-);
+module:hook("s2s-stream-features", function(event)
+ local origin, features = event.origin, event.features;
+ if not origin.compressed and origin.type == "s2sin" then
+ features:add_child(compression_stream_feature);
+ end
+end);
--- S2Sout handling aka the client perspective in the S2S connection
+-- Hook to activate compression if remote server supports it.
module:hook_stanza(xmlns_stream, "features",
function (session, stanza)
- if not session.compressed then
- module:log("debug", "FEATURES: "..stanza:pretty_print())
+ if not session.compressed and session.type == "s2sout" then
-- does remote server support compression?
- local comp_st = stanza:child_with_name("compression");
+ local comp_st = stanza:get_child("compression", xmlns_compression_feature);
if comp_st then
-- do we support the mechanism
- for a in comp_st:children() do
- local algorithm = a[1]
+ for a in comp_st:childtags("method") do
+ local algorithm = a:get_text();
if algorithm == "zlib" then
session.sends2s(st.stanza("compress", {xmlns=xmlns_compression_protocol}):tag("method"):text("zlib"))
- session.log("info", "Enabled compression using zlib.")
+ session.log("debug", "Enabled compression using zlib.")
return true;
end
end
end
, 250);
--- TODO Support compression on S2S level too.
-module:add_handler({"s2sout_unauthed", "s2sout"}, "compressed", xmlns_compression_protocol,
- function(session ,stanza)
- session.log("debug", "Activating compression...")
+
+-- returns either nil or a fully functional ready to use inflate stream
+local function get_deflate_stream(session)
+ 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.sends2s or session.send)(error_st);
+ session.log("error", "Failed to create zlib.deflate filter.");
+ module:log("error", "%s", tostring(deflate_stream));
+ return
+ end
+ return deflate_stream
+end
+
+-- returns either nil or a fully functional ready to use inflate stream
+local function get_inflate_stream(session)
+ 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.sends2s or session.send)(error_st);
+ session.log("error", "Failed to create zlib.inflate filter.");
+ module:log("error", "%s", tostring(inflate_stream));
+ return
+ end
+ return inflate_stream
+end
+
+-- setup compression for a stream
+local function setup_compression(session, deflate_stream)
+ add_filter(session, "bytes/out", function(t)
+ local status, compressed, eof = pcall(deflate_stream, tostring(t), 'sync');
+ if status == false then
+ module:log("warn", "%s", tostring(compressed));
+ session:close({
+ condition = "undefined-condition";
+ text = compressed;
+ extra = st.stanza("failure", {xmlns="http://jabber.org/protocol/compress"}):tag("processing-failed");
+ });
+ return;
end
-);
-
-module:add_handler({"c2s_unauthed", "c2s", "s2sin_unauthed", "s2sin"}, "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.sends2s or 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.sends2s or 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.sends2s or 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 function setup_compression(session)
- local old_send = (session.sends2s or session.send);
-
- local new_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;
-
- if session.sends2s then session.sends2s = new_send
- elseif session.send then session.send = new_send end
- end
- setup_compression(session);
-
- -- 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");
- (session.sends2s or session.send)(error_st);
- end
+ return compressed;
+ end);
+end
+
+-- setup decompression for a stream
+local function setup_decompression(session, inflate_stream)
+ add_filter(session, "bytes/in", function(data)
+ local status, decompressed, eof = pcall(inflate_stream, data);
+ if status == false then
+ module:log("warn", "%s", tostring(decompressed));
+ session:close({
+ condition = "undefined-condition";
+ text = decompressed;
+ extra = st.stanza("failure", {xmlns="http://jabber.org/protocol/compress"}):tag("processing-failed");
+ });
+ return;
+ end
+ return decompressed;
+ end);
+end
+
+module:hook("stanza/http://jabber.org/protocol/compress:compressed", function(event)
+ local session = event.origin;
+
+ if session.type == "s2sout" then
+ session.log("debug", "Activating compression...")
+ -- create deflate and inflate streams
+ local deflate_stream = get_deflate_stream(session);
+ if not deflate_stream then return true; end
+
+ local inflate_stream = get_inflate_stream(session);
+ if not inflate_stream then return true; end
+
+ -- setup compression for session.w
+ setup_compression(session, deflate_stream);
+
+ -- setup decompression for session.data
+ setup_decompression(session, inflate_stream);
+ session:reset_stream();
+ session:open_stream(session.from_host, session.to_host);
+ session.compressed = true;
+ return true;
+ end
+end);
+
+module:hook("stanza/http://jabber.org/protocol/compress:failure", function(event)
+ local err = event.stanza:get_child();
+ (event.origin.log or module._log)("warn", "Compression setup failed (%s)", err and err.name or "unknown reason");
+ return true;
+end);
+
+module:hook("stanza/http://jabber.org/protocol/compress:compress", function(event)
+ local session, stanza = event.origin, event.stanza;
+
+ if session.type == "c2s" or session.type == "s2sin" then
+ -- fail if we are already compressed
+ if session.compressed then
+ local error_st = st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("setup-failed");
+ (session.sends2s or session.send)(error_st);
+ session.log("debug", "Client tried to establish another compression layer.");
+ return true;
+ end
+
+ -- checking if the compression method is supported
+ local method = stanza:get_child_text("method");
+ if method == "zlib" then
+ session.log("debug", "zlib compression enabled.");
+
+ -- create deflate and inflate streams
+ local deflate_stream = get_deflate_stream(session);
+ if not deflate_stream then return true; end
+
+ local inflate_stream = get_inflate_stream(session);
+ if not inflate_stream then return true; end
+
+ (session.sends2s or session.send)(st.stanza("compressed", {xmlns=xmlns_compression_protocol}));
+ session:reset_stream();
+
+ -- setup compression for session.w
+ setup_compression(session, deflate_stream);
+
+ -- setup decompression for session.data
+ setup_decompression(session, inflate_stream);
+
+ session.compressed = true;
+ elseif method then
+ session.log("debug", "%s compression selected, but we don't support it.", tostring(method));
+ local error_st = st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("unsupported-method");
+ (session.sends2s or session.send)(error_st);
+ else
+ (session.sends2s or session.send)(st.stanza("failure", {xmlns=xmlns_compression_protocol}):tag("setup-failed"));
end
-);
+ return true;
+ end
+end);