diff options
Diffstat (limited to 'plugins')
-rw-r--r-- | plugins/mod_compression.lua | 206 |
1 files changed, 148 insertions, 58 deletions
diff --git a/plugins/mod_compression.lua b/plugins/mod_compression.lua index f1cae737..8fdf9dcc 100644 --- a/plugins/mod_compression.lua +++ b/plugins/mod_compression.lua @@ -8,16 +8,16 @@ local st = require "util.stanza"; 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 xmlns_stream = "http://etherx.jabber.org/streams"; local compression_stream_feature = st.stanza("compression", {xmlns=xmlns_compression_feature}):tag("method"):text("zlib"):up(); 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; + 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)); @@ -34,89 +34,179 @@ module:add_event_hook("stream-features", end ); --- TODO Support compression on S2S level too. -module:add_handler({"c2s_unauthed", "c2s"}, "compress", xmlns_compression_protocol, +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 + if not session.compressed then + features:add_child(compression_stream_feature); + end + end +); + +-- Hook to activate compression if remote server supports it. +module:hook_stanza(xmlns_stream, "features", + function (session, stanza) + if not session.compressed then + -- does remote server support compression? + local comp_st = stanza:child_with_name("compression"); + if comp_st then + -- do we support the mechanism + for a in comp_st:children() do + local algorithm = a[1] + if algorithm == "zlib" then + session.sends2s(st.stanza("compress", {xmlns=xmlns_compression_protocol}):tag("method"):text("zlib")) + session.log("info", "Enabled compression using zlib.") + return true; + end + end + session.log("debug", "Remote server supports no compression algorithm we support.") + end + end + end +, 250); + + +-- 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", 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.deflate filter."); + module:log("error", inflate_stream); + return + end + return inflate_stream +end + +-- setup compression for a stream +local function setup_compression(session, deflate_stream) + local old_send = (session.sends2s or session.send); + + local new_send = function(t) + --TODO: Better code injection in the sending process + session.log(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 + session.conn:write(compressed); + end; + + if session.sends2s then session.sends2s = new_send + elseif session.send then session.send = new_send end +end + +-- setup decompression for a stream +local function setup_decompression(session, inflate_stream) + 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 + +module:add_handler({"s2sout_unauthed", "s2sout"}, "compressed", xmlns_compression_protocol, + function(session ,stanza) + session.log("debug", "Activating compression...") + -- create deflate and inflate streams + local deflate_stream = get_deflate_stream(session); + if not deflate_stream then return end + + local inflate_stream = get_inflate_stream(session); + if not inflate_stream then return end + + -- setup compression for session.w + setup_compression(session, deflate_stream); + + -- setup decompression for session.data + setup_decompression(session, inflate_stream); + local session_reset_stream = session.reset_stream; + session.reset_stream = function(session) + session_reset_stream(session); + setup_decompression(session, inflate_stream); + return true; + end; + session:reset_stream(); + local default_stream_attr = {xmlns = "jabber:server", ["xmlns:stream"] = "http://etherx.jabber.org/streams", + ["xmlns:db"] = 'jabber:server:dialback', version = "1.0", to = session.to_host, from = session.from_host}; + session.sends2s("<?xml version='1.0'?>"); + session.sends2s(st.stanza("stream:stream", default_stream_attr):top_tag()); + session.compressed = true; + 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."); + (session.sends2s or 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 deflate_stream = get_deflate_stream(session); + if not deflate_stream then 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 + local inflate_stream = get_inflate_stream(session); + if not inflate_stream then return end - -- setup compression for session.w - local old_send = session.send; + (session.sends2s or session.send)(st.stanza("compressed", {xmlns=xmlns_compression_protocol})); + session:reset_stream(); - 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 compression for session.w + setup_compression(session, deflate_stream); -- 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); + setup_decompression(session, inflate_stream); local session_reset_stream = session.reset_stream; session.reset_stream = function(session) session_reset_stream(session); - setup_decompression(session); + setup_decompression(session, inflate_stream); 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.send(error_st); + (session.sends2s or session.send)(error_st); end end ); + |