* luci/libs: add support for chunked transfer decoding in http.protocol

libs/http/luasrc/http/protocol.lua

@@ -17,6 +17,7 @@ module("luci.http.protocol", package.seeall)
 
 require("ltn12")
 require("luci.util")
+require("luci.http.protocol.filter")
 
 HTTP_MAX_CONTENT      = 1024*4		-- 4 kB maximum content size
 HTTP_URLENC_MAXKEYLEN = 1024		-- maximum allowd size of urlencoded parameter names
@@ -127,7 +128,7 @@ process_states['magic'] = function( msg, chunk )
 			msg.type           = "request"
 			msg.request_method = method:lower()
 			msg.request_uri    = uri
-			msg.http_version   = http_ver
+			msg.http_version   = tonumber( http_ver )
 			msg.headers        = { }
 
 			-- We're done, next state is header parsing
@@ -146,7 +147,7 @@ process_states['magic'] = function( msg, chunk )
 				msg.type           = "response"
 				msg.status_code    = code
 				msg.status_message = message
-				msg.http_version   = http_ver
+				msg.http_version   = tonumber( http_ver )
 				msg.headers        = { }
 
 				-- We're done, next state is header parsing
@@ -701,6 +702,18 @@ end
 -- Parse a http message body
 function parse_message_body( source, msg, filecb )
 
+	-- Install an additional filter if we're operating on chunked transfer
+	-- coding and client is HTTP/1.1 capable
+	if msg.http_version == 1.1 and
+	   msg.headers['Transfer-Encoding'] and
+	   msg.headers['Transfer-Encoding']:find("chunked")
+	then
+		source = ltn12.source.chain(
+			source, luci.http.protocol.filter.decode_chunked
+		)
+	end
+
+
 	-- Is it multipart/mime ?
 	if msg.env.REQUEST_METHOD == "POST" and msg.env.CONTENT_TYPE and
 	   msg.env.CONTENT_TYPE:match("^multipart/form%-data")
@@ -721,7 +734,6 @@ function parse_message_body( source, msg, filecb )
 	else
 
 		local sink
-		local length = 0
 
 		-- If we have a file callback then feed it
 		if type(filecb) == "function" then
@@ -733,7 +745,7 @@ function parse_message_body( source, msg, filecb )
 			msg.content_length = 0
 
 			sink = function( chunk )
-				if ( msg.content_length ) + #chunk <= HTTP_MAX_CONTENT then
+				if ( msg.content_length + #chunk ) <= HTTP_MAX_CONTENT then
 
 					msg.content        = msg.content        .. chunk
 					msg.content_length = msg.content_length + #chunk

libs/http/luasrc/http/protocol/filter.lua

@@ -0,0 +1,81 @@
+--[[
+
+HTTP protocol implementation for LuCI - filter implementation
+(c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+$Id$
+
+]]--
+
+module("luci.http.protocol.filter", package.seeall)
+
+require("ltn12")
+
+
+-- Factory that produces a filter which normalizes chunked transfer encoding
+function decode_chunked()
+
+	local length = 0
+	local read   = 0
+
+	return ltn12.filter.cycle(
+		function( chunk, ctx )
+
+			if chunk ~= nil then
+
+				-- EOF
+				if ctx == nil then
+					if ( length - read ) > 0 then
+						return nil, "Unexpected EOF"
+					else
+						return ""
+					end
+				end
+
+				chunk = ctx .. chunk
+
+				local buf = ""
+				while true do
+
+					if read == length then
+
+						-- Find chunk length indicator
+						local spos, epos = chunk:find("^\r?\n?[a-fA-F0-9]+ *\r\n")
+						if spos and spos == 1 then
+							read   = 0
+							length = tonumber(
+								chunk:sub( 1, epos ):gsub( "[^a-fA-F0-9]", "" ), 16
+							)
+
+							-- Check for end of chunk
+							if length > 0 then
+								chunk = chunk:sub( epos + 1, #chunk )
+							else
+								return buf, ""
+							end
+						else
+							return "", nil
+						end
+					else
+						if ( read + #chunk ) <= length then
+							read = read + #chunk
+							return buf .. chunk, ""
+						else
+							local rest = length - read
+							read  = read + rest
+							buf   = buf .. chunk:sub( 1, rest )
+							chunk = chunk:sub( rest + 1, #chunk )
+						end
+					end
+				end
+			end
+		end,
+		""
+	)
+end