GSoC Commit #1: LuCId + HTTP-Server

1 files changed, 522 insertions, 0 deletions

diff --git a/libs/lucid-http/luasrc/lucid/http/server.lua b/libs/lucid-http/luasrc/lucid/http/server.lua
new file mode 100644
index 000000000..f5de4e9a1
--- /dev/null
+++ b/libs/lucid-http/luasrc/lucid/http/server.lua
@@ -0,0 +1,522 @@
+--[[
+LuCId HTTP-Slave
+(c) 2009 Steven Barth <steven@midlink.org>
+
+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
+
+$Id$
+]]--
+
+local ipairs, pairs = ipairs, pairs
+local tostring, tonumber = tostring, tonumber
+local pcall, assert, type = pcall, assert, type
+
+local os = require "os"
+local nixio = require "nixio"
+local util = require "luci.util"
+local ltn12 = require "luci.ltn12"
+local proto = require "luci.http.protocol"
+local table = require "table"
+local date = require "luci.http.protocol.date"
+
+module "luci.lucid.http.server"
+
+VERSION = "1.0"
+
+statusmsg = {
+	[200] = "OK",
+	[206] = "Partial Content",
+	[301] = "Moved Permanently",
+	[302] = "Found",
+	[304] = "Not Modified",
+	[400] = "Bad Request",
+	[401] = "Unauthorized",
+	[403] = "Forbidden",
+	[404] = "Not Found",
+	[405] = "Method Not Allowed",
+	[408] = "Request Time-out",
+	[411] = "Length Required",
+	[412] = "Precondition Failed",
+	[416] = "Requested range not satisfiable",
+	[500] = "Internal Server Error",
+	[503] = "Server Unavailable",
+}
+
+-- File Resource
+IOResource = util.class()
+
+function IOResource.__init__(self, fd, len)
+	self.fd, self.len = fd, len
+end
+
+
+-- Server handler implementation
+Handler = util.class()
+
+function Handler.__init__(self, name)
+	self.name = name or tostring(self)
+end
+
+-- Creates a failure reply
+function Handler.failure(self, code, msg)	
+	return code, { ["Content-Type"] = "text/plain" }, ltn12.source.string(msg)
+end
+
+-- Access Restrictions
+function Handler.restrict(self, restriction)
+	if not self.restrictions then
+		self.restrictions = {restriction}
+	else
+		self.restrictions[#self.restrictions+1] = restriction
+	end
+end
+
+-- Check restrictions
+function Handler.checkrestricted(self, request)
+	if not self.restrictions then
+		return
+	end
+
+	local localif, user, pass
+	
+	for _, r in ipairs(self.restrictions) do
+		local stat = true
+		if stat and r.interface then	-- Interface restriction
+			if not localif then
+				for _, v in ipairs(request.server.interfaces) do
+					if v.addr == request.env.SERVER_ADDR then
+						localif = v.name
+						break
+					end
+				end
+			end
+			
+			if r.interface ~= localif then
+				stat = false
+			end
+		end
+		
+		if stat and r.user then	-- User restriction
+			local rh, pwe
+			if not user then
+				rh = (request.headers.Authorization or ""):match("Basic (.*)")
+				rh = rh and nixio.bin.b64decode(rh) or ""
+				user, pass = rh:match("(.*):(.*)")
+				pass = pass or ""
+			end
+			pwe = nixio.getsp and nixio.getsp(r.user) or nixio.getpw(r.user)
+			local pwh = (user == r.user) and pwe and (pwe.pwdp or pwe.passwd)
+			if not pwh or #pwh < 1 or nixio.crypt(pass, pwh) ~= pwh then
+				stat = false
+			end
+		end
+		
+		if stat then
+			return
+		end
+	end
+	
+	return 401, {
+		["WWW-Authenticate"] = ('Basic realm=%q'):format(self.name),
+		["Content-Type"] = 'text/plain'
+	}, ltn12.source.string("Unauthorized")
+end
+
+-- Processes a request
+function Handler.process(self, request, sourcein)
+	local stat, code, hdr, sourceout
+	
+	local stat, code, msg = self:checkrestricted(request)
+	if stat then	-- Access Denied
+		return stat, code, msg
+	end
+
+	-- Detect request Method
+	local hname = "handle_" .. request.env.REQUEST_METHOD
+	if self[hname] then
+		-- Run the handler
+		stat, code, hdr, sourceout = pcall(self[hname], self, request, sourcein)
+
+		-- Check for any errors
+		if not stat then
+			return self:failure(500, code)
+		end
+	else
+		return self:failure(405, statusmsg[405])
+	end
+
+	return code, hdr, sourceout
+end
+
+
+VHost = util.class()
+
+function VHost.__init__(self)
+	self.handlers = {}
+end
+
+function VHost.process(self, request, ...)
+	local handler
+	local hlen = -1
+	local uri = request.env.SCRIPT_NAME
+	local sc = ("/"):byte()
+
+	-- SCRIPT_NAME
+	request.env.SCRIPT_NAME = ""
+
+	-- Call URI part
+	request.env.PATH_INFO = uri
+	
+	for k, h in pairs(self.handlers) do
+		if #k > hlen then
+			if uri == k or (uri:sub(1, #k) == k and uri:byte(#k+1) == sc) then
+				handler = h
+				hlen = #k
+				request.env.SCRIPT_NAME = k
+				request.env.PATH_INFO   = uri:sub(#k+1)
+			end
+		end
+	end
+	
+	if handler then
+		return handler:process(request, ...)
+	else
+		return 404, nil, ltn12.source.string("No such handler")
+	end
+end
+
+function VHost.get_handlers(self)
+	return self.handlers
+end
+
+function VHost.set_handler(self, match, handler)
+	self.handlers[match] = handler
+end
+
+
+local function remapipv6(adr)
+	local map = "::ffff:"
+	if adr:sub(1, #map) == map then
+		return adr:sub(#map+1)
+	else
+		return adr
+	end 
+end
+
+local function chunksource(sock, buffer)
+	buffer = buffer or ""
+	return function()
+		local output
+		local _, endp, count = buffer:find("^([0-9a-fA-F]+);?.-\r\n")
+		while not count and #buffer <= 1024 do
+			local newblock, code = sock:recv(1024 - #buffer)
+			if not newblock then
+				return nil, code
+			end
+			buffer = buffer .. newblock  
+			_, endp, count = buffer:find("^([0-9a-fA-F]+);?.-\r\n")
+		end
+		count = tonumber(count, 16)
+		if not count then
+			return nil, -1, "invalid encoding"
+		elseif count == 0 then
+			return nil
+		elseif count + 2 <= #buffer - endp then
+			output = buffer:sub(endp+1, endp+count)
+			buffer = buffer:sub(endp+count+3)
+			return output
+		else
+			output = buffer:sub(endp+1, endp+count)
+			buffer = ""
+			if count - #output > 0 then
+				local remain, code = sock:recvall(count-#output)
+				if not remain then
+					return nil, code
+				end
+				output = output .. remain
+				count, code = sock:recvall(2)
+			else
+				count, code = sock:recvall(count+2-#buffer+endp)
+			end
+			if not count then
+				return nil, code
+			end
+			return output
+		end
+	end
+end
+
+local function chunksink(sock)
+	return function(chunk, err)
+		if not chunk then
+			return sock:writeall("0\r\n\r\n")
+		else
+			return sock:writeall(("%X\r\n%s\r\n"):format(#chunk, chunk))
+		end
+	end
+end
+
+Server = util.class()
+
+function Server.__init__(self)
+	self.vhosts = {}
+end
+
+function Server.get_vhosts(self)
+	return self.vhosts
+end
+
+function Server.set_vhost(self, name, vhost)
+	self.vhosts[name] = vhost
+end
+
+function Server.error(self, client, code, msg)
+	hcode = tostring(code)
+	
+	client:writeall( "HTTP/1.0 " .. hcode .. " " ..
+	 statusmsg[code] .. "\r\n" )
+	client:writeall( "Connection: close\r\n" )
+	client:writeall( "Content-Type: text/plain\r\n\r\n" )
+
+	if msg then
+		client:writeall( "HTTP-Error " .. code .. ": " .. msg .. "\r\n" )
+	end
+	
+	client:close()
+end
+
+local hdr2env = {
+	["Content-Length"] = "CONTENT_LENGTH",
+	["Content-Type"] = "CONTENT_TYPE",
+	["Content-type"] = "CONTENT_TYPE",
+	["Accept"] = "HTTP_ACCEPT",
+	["Accept-Charset"] = "HTTP_ACCEPT_CHARSET",
+	["Accept-Encoding"] = "HTTP_ACCEPT_ENCODING",
+	["Accept-Language"] = "HTTP_ACCEPT_LANGUAGE",
+	["Connection"] = "HTTP_CONNECTION",
+	["Cookie"] = "HTTP_COOKIE",
+	["Host"] = "HTTP_HOST",
+	["Referer"] = "HTTP_REFERER",
+	["User-Agent"] = "HTTP_USER_AGENT"
+}
+
+function Server.parse_headers(self, source)
+	local env = {}
+	local req = {env = env, headers = {}}
+	local line, err
+
+	repeat	-- Ignore empty lines
+		line, err = source()
+		if not line then
+			return nil, err
+		end
+	until #line > 0
+	
+	env.REQUEST_METHOD, env.REQUEST_URI, env.SERVER_PROTOCOL =
+		line:match("^([A-Z]+) ([^ ]+) (HTTP/1%.[01])$")
+		
+	if not env.REQUEST_METHOD then
+		return nil, "invalid magic"
+	end
+	
+	local key, envkey, val
+	repeat
+		line, err = source()
+		if not line then
+			return nil, err
+		elseif #line > 0 then	
+			key, val = line:match("^([%w-]+)%s?:%s?(.*)")
+			if key then
+				req.headers[key] = val
+				envkey = hdr2env[key]
+				if envkey then
+					env[envkey] = val
+				end
+			else
+				return nil, "invalid header line"
+			end
+		else
+			break
+		end
+	until false
+	
+	env.SCRIPT_NAME, env.QUERY_STRING = env.REQUEST_URI:match("(.*)%??(.*)")
+	return req
+end
+
+
+function Server.process(self, client, env)
+	local sourcein  = function() end
+	local sourcehdr = client:linesource()
+	local sinkout
+	local buffer
+	
+	local close = false
+	local stat, code, msg, message, err
+	
+	client:setsockopt("socket", "rcvtimeo", 15)
+	client:setsockopt("socket", "sndtimeo", 15)
+	
+	repeat
+		-- parse headers
+		message, err = self:parse_headers(sourcehdr)
+
+		-- any other error
+		if not message or err then
+			if err == 11 then	-- EAGAIN
+				break
+			else
+				return self:error(client, 400, err)
+			end
+		end
+
+		-- Prepare sources and sinks
+		buffer = sourcehdr(true)
+		sinkout = client:sink()
+		message.server = env
+		
+		if client:is_tls_socket() then
+			message.env.HTTPS = "on"
+		end
+		
+		-- Addresses
+		message.env.REMOTE_ADDR = remapipv6(env.host)
+		message.env.REMOTE_PORT = env.port
+		
+		local srvaddr, srvport = client:getsockname()
+		message.env.SERVER_ADDR = remapipv6(srvaddr)
+		message.env.SERVER_PORT = srvport
+		
+		-- keep-alive
+		if message.env.SERVER_PROTOCOL == "HTTP/1.1" then
+			close = (message.env.HTTP_CONNECTION == "close")
+		else
+			close = not message.env.HTTP_CONNECTION 
+				or message.env.HTTP_CONNECTION == "close"
+		end
+
+		-- Uncomment this to disable keep-alive
+		close = close or env.config.nokeepalive
+	
+		if message.env.REQUEST_METHOD == "GET"
+		or message.env.REQUEST_METHOD == "HEAD" then
+			-- Be happy
+			
+		elseif message.env.REQUEST_METHOD == "POST" then
+			-- If we have a HTTP/1.1 client and an Expect: 100-continue header
+			-- respond with HTTP 100 Continue message
+			if message.env.SERVER_PROTOCOL == "HTTP/1.1" 
+			and message.headers.Expect == '100-continue' then
+				client:writeall("HTTP/1.1 100 Continue\r\n\r\n")
+			end
+			
+			if message.headers['Transfer-Encoding'] and
+			 message.headers['Transfer-Encoding'] ~= "identity" then
+				sourcein = chunksource(client, buffer)
+				buffer = nil
+			elseif message.env.CONTENT_LENGTH then
+				local len = tonumber(message.env.CONTENT_LENGTH)
+				if #buffer >= len then
+					sourcein = ltn12.source.string(buffer:sub(1, len))
+					buffer = buffer:sub(len+1)
+				else
+					sourcein = ltn12.source.cat(
+						ltn12.source.string(buffer),
+						client:blocksource(nil, len - #buffer)
+					)
+				end
+			else
+				return self:error(client, 411, statusmsg[411])
+			end
+		else
+			return self:error(client, 405, statusmsg[405])
+		end
+
+
+		local host = self.vhosts[message.env.HTTP_HOST] or self.vhosts[""]
+		if not host then
+			return self:error(client, 404, "No virtual host found")
+		end
+		
+		local code, headers, sourceout = host:process(message, sourcein)
+		headers = headers or {}
+		
+		-- Post process response
+		if sourceout then
+			if util.instanceof(sourceout, IOResource) then
+				if not headers["Content-Length"] then
+					headers["Content-Length"] = sourceout.len
+				end
+			end
+			if not headers["Content-Length"] then
+				if message.http_version == 1.1 then
+					headers["Transfer-Encoding"] = "chunked"
+					sinkout = chunksink(client)
+				else
+					close = true
+				end
+			end
+		elseif message.request_method ~= "head" then
+			headers["Content-Length"] = 0
+		end
+		
+		if close then
+			headers["Connection"] = "close"
+		elseif message.env.SERVER_PROTOCOL == "HTTP/1.0" then
+			headers["Connection"] = "Keep-Alive"
+		end 
+
+		headers["Date"] = date.to_http(os.time())
+		local header = {
+			message.env.SERVER_PROTOCOL .. " " .. tostring(code) .. " " 
+				.. statusmsg[code],
+			"Server: LuCId-HTTPd/" .. VERSION
+		}
+
+		
+		for k, v in pairs(headers) do
+			if type(v) == "table" then
+				for _, h in ipairs(v) do
+					header[#header+1] = k .. ": " .. h
+				end
+			else
+				header[#header+1] = k .. ": " .. v
+			end
+		end
+
+		header[#header+1] = ""
+		header[#header+1] = ""
+		
+		-- Output
+		stat, code, msg = client:writeall(table.concat(header, "\r\n"))
+
+		if sourceout and stat then
+			if util.instanceof(sourceout, IOResource) then
+				stat, code, msg = sourceout.fd:copyz(client, sourceout.len)
+			else
+				stat, msg = ltn12.pump.all(sourceout, sinkout)
+			end
+		end
+
+
+		-- Write errors
+		if not stat then
+			if msg then
+				nixio.syslog("err", "Error sending data to " .. env.host ..
+					": " .. msg .. "\n")
+			end
+			break
+		end
+		
+		if buffer then
+			sourcehdr(buffer)
+		end
+	until close
+	
+	client:shutdown()
+	client:close()
+end