---[[
-
+--[[
+
HTTP protocol implementation for LuCI
-(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
-
-$Id$
-
-]]--
+(c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
-module("luci.http.protocol", package.seeall)
+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
-require("luci.util")
+ http://www.apache.org/licenses/LICENSE-2.0
+$Id$
-HTTP_MAX_CONTENT = 1024^2 -- 1 MB maximum content size
-HTTP_MAX_READBUF = 1024 -- 1 kB read buffer size
+]]--
+
+--- LuCI http protocol class.
+-- This class contains several functions useful for http message- and content
+-- decoding and to retrive form data from raw http messages.
+module("luci.http.protocol", package.seeall)
-HTTP_DEFAULT_CTYPE = "text/html" -- default content type
-HTTP_DEFAULT_VERSION = "1.0" -- HTTP default version
+local ltn12 = require("luci.ltn12")
+HTTP_MAX_CONTENT = 1024*8 -- 8 kB maximum content size
--- Decode an urlencoded string.
--- Returns the decoded value.
-function urldecode( str )
+--- Decode an urlencoded string - optionally without decoding
+-- the "+" sign to " " - and return the decoded string.
+-- @param str Input string in x-www-urlencoded format
+-- @param no_plus Don't decode "+" signs to spaces
+-- @return The decoded string
+-- @see urlencode
+function urldecode( str, no_plus )
local function __chrdec( hex )
return string.char( tonumber( hex, 16 ) )
end
if type(str) == "string" then
- str = str:gsub( "+", " " ):gsub( "%%([a-fA-F0-9][a-fA-F0-9])", __chrdec )
+ if not no_plus then
+ str = str:gsub( "+", " " )
+ end
+
+ str = str:gsub( "%%([a-fA-F0-9][a-fA-F0-9])", __chrdec )
end
return str
end
+--- Extract and split urlencoded data pairs, separated bei either "&" or ";"
+-- from given url or string. Returns a table with urldecoded values.
+-- Simple parameters are stored as string values associated with the parameter
+-- name within the table. Parameters with multiple values are stored as array
+-- containing the corresponding values.
+-- @param url The url or string which contains x-www-urlencoded form data
+-- @param tbl Use the given table for storing values (optional)
+-- @return Table containing the urldecoded parameters
+-- @see urlencode_params
+function urldecode_params( url, tbl )
--- Extract and split urlencoded data pairs, separated bei either "&" or ";" from given url.
--- Returns a table value with urldecoded values.
-function urldecode_params( url )
-
- local params = { }
+ local params = tbl or { }
if url:find("?") then
url = url:gsub( "^.+%?([^?]+)", "%1" )
end
- for i, pair in ipairs(luci.util.split( url, "[&;]+", nil, true )) do
+ for pair in url:gmatch( "[^&;]+" ) do
-- find key and value
local key = urldecode( pair:match("^([^=]+)") )
return params
end
-
--- Encode given string in urlencoded format.
--- Returns the encoded string.
+--- Encode given string to x-www-urlencoded format.
+-- @param str String to encode
+-- @return String containing the encoded data
+-- @see urldecode
function urlencode( str )
local function __chrenc( chr )
if type(str) == "string" then
str = str:gsub(
- "([^a-zA-Z0-9$_%-%.+!*'(),])",
+ "([^a-zA-Z0-9$_%-%.%+!*'(),])",
__chrenc
)
end
return str
end
-
--- Encode given table to urlencoded string.
--- Returns the encoded string.
+--- Encode each key-value-pair in given table to x-www-urlencoded format,
+-- separated by "&". Tables are encoded as parameters with multiple values by
+-- repeating the parameter name with each value.
+-- @param tbl Table with the values
+-- @return String containing encoded values
+-- @see urldecode_params
function urlencode_params( tbl )
local enc = ""
for k, v in pairs(tbl) do
- enc = enc .. ( enc and "&" or "" ) ..
- urlencode(k) .. "=" ..
- urlencode(v)
+ if type(v) == "table" then
+ for i, v2 in ipairs(v) do
+ enc = enc .. ( #enc > 0 and "&" or "" ) ..
+ urlencode(k) .. "=" .. urlencode(v2)
+ end
+ else
+ enc = enc .. ( #enc > 0 and "&" or "" ) ..
+ urlencode(k) .. "=" .. urlencode(v)
+ end
end
return enc
end
+-- (Internal function)
+-- Initialize given parameter and coerce string into table when the parameter
+-- already exists.
+-- @param tbl Table where parameter should be created
+-- @param key Parameter name
+-- @return Always nil
+local function __initval( tbl, key )
+ if tbl[key] == nil then
+ tbl[key] = ""
+ elseif type(tbl[key]) == "string" then
+ tbl[key] = { tbl[key], "" }
+ else
+ table.insert( tbl[key], "" )
+ end
+end
--- Decode MIME encoded data.
--- Returns a table with decoded values.
-function mimedecode( data, boundary, filecb )
-
- local params = { }
-
- -- create a line reader
- local reader = _linereader( data, HTTP_MAX_READBUF )
-
- -- state variables
- local in_part = false
- local in_file = false
- local in_fbeg = false
- local in_size = true
-
- local filename
- local buffer
- local field
- local clen = 0
-
- -- try to read all mime parts
- for line, eol in reader do
-
- -- update content length
- clen = clen + line:len()
-
- if clen >= HTTP_MAX_CONTENT then
- in_size = false
- end
-
- -- when no boundary is given, try to find it
- if not boundary then
- boundary = line:match("^%-%-([^\r\n]+)\r?\n$")
- end
-
- -- Got a valid boundary line or reached max allowed size.
- if ( boundary and line:sub(1,2) == "--" and line:len() > #boundary + 2 and
- line:sub( 3, 2 + #boundary ) == boundary ) or not in_size
- then
- -- Flush the data of the previous mime part.
- -- When field and/or buffer are set to nil we should discard
- -- the previous section entirely due to format violations.
- if type(field) == "string" and field:len() > 0 and
- type(buffer) == "string"
- then
- -- According to the rfc the \r\n preceeding a boundary
- -- is assumed to be part of the boundary itself.
- -- Since we are reading line by line here, this crlf
- -- is part of the last line of our section content,
- -- so strip it before storing the buffer.
- buffer = buffer:gsub("\r?\n$","")
-
- -- If we're in a file part and a file callback has been provided
- -- then do a final call and send eof.
- if in_file and type(filecb) == "function" then
- filecb( field, filename, buffer, true )
- params[field] = filename
-
- -- Store buffer.
- else
- params[field] = buffer
- end
- end
-
- -- Reset vars
- buffer = ""
- filename = nil
- field = nil
- in_file = false
-
- -- Abort here if we reached maximum allowed size
- if not in_size then break end
-
- -- Do we got the last boundary?
- if line:len() > #boundary + 4 and
- line:sub( #boundary + 2, #boundary + 4 ) == "--"
- then
- -- No more processing
- in_part = false
-
- -- It's a middle boundary
- else
-
- -- Read headers
- local hlen, headers = extract_headers( reader )
-
- -- Check for valid headers
- if headers['Content-Disposition'] then
-
- -- Got no content type header, assume content-type "text/plain"
- if not headers['Content-Type'] then
- headers['Content-Type'] = 'text/plain'
- end
-
- -- Find field name
- local hdrvals = luci.util.split(
- headers['Content-Disposition'], '; '
- )
-
- -- Valid form data part?
- if hdrvals[1] == "form-data" and hdrvals[2]:match("^name=") then
-
- -- Store field identifier
- field = hdrvals[2]:match('^name="(.+)"$')
-
- -- Do we got a file upload field?
- if #hdrvals == 3 and hdrvals[3]:match("^filename=") then
- in_file = true
- if_fbeg = true
- filename = hdrvals[3]:match('^filename="(.+)"$')
- end
-
- -- Entering next part processing
- in_part = true
- end
- end
- end
-
- -- Processing content
- elseif in_part then
-
- -- XXX: Would be really good to switch from line based to
- -- buffered reading here.
-
-
- -- If we're in a file part and a file callback has been provided
- -- then call the callback and reset the buffer.
- if in_file and type(filecb) == "function" then
-
- -- If we're not processing the first chunk, then call
- if not in_fbeg then
- filecb( field, filename, buffer, false )
- buffer = ""
-
- -- Clear in_fbeg flag after first run
- else
- in_fbeg = false
- end
- end
+-- (Internal function)
+-- Append given data to given parameter, either by extending the string value
+-- or by appending it to the last string in the parameter's value table.
+-- @param tbl Table containing the previously initialized parameter value
+-- @param key Parameter name
+-- @param chunk String containing the data to append
+-- @return Always nil
+-- @see __initval
+local function __appendval( tbl, key, chunk )
+ if type(tbl[key]) == "table" then
+ tbl[key][#tbl[key]] = tbl[key][#tbl[key]] .. chunk
+ else
+ tbl[key] = tbl[key] .. chunk
+ end
+end
- -- Append date to buffer
- buffer = buffer .. line
+-- (Internal function)
+-- Finish the value of given parameter, either by transforming the string value
+-- or - in the case of multi value parameters - the last element in the
+-- associated values table.
+-- @param tbl Table containing the previously initialized parameter value
+-- @param key Parameter name
+-- @param handler Function which transforms the parameter value
+-- @return Always nil
+-- @see __initval
+-- @see __appendval
+local function __finishval( tbl, key, handler )
+ if handler then
+ if type(tbl[key]) == "table" then
+ tbl[key][#tbl[key]] = handler( tbl[key][#tbl[key]] )
+ else
+ tbl[key] = handler( tbl[key] )
end
end
-
- return params
end
+-- Table of our process states
+local process_states = { }
+
-- Extract "magic", the first line of a http message.
--- Returns the message type ("get", "post" or "response"), the requested uri
--- if it is a valid http request or the status code if the line descripes a
--- http response. For requests the third parameter is nil, for responses it
--- contains the human readable status description.
-function extract_magic( reader )
+-- Extracts the message type ("get", "post" or "response"), the requested uri
+-- or the status code if the line descripes a http response.
+process_states['magic'] = function( msg, chunk, err )
+
+ if chunk ~= nil then
+ -- ignore empty lines before request
+ if #chunk == 0 then
+ return true, nil
+ end
- for line in reader do
-- Is it a request?
- local method, uri = line:match("^([A-Z]+) ([^ ]+) HTTP/[01]%.[019]\r?\n$")
+ local method, uri, http_ver = chunk:match("^([A-Z]+) ([^ ]+) HTTP/([01]%.[019])$")
-- Yup, it is
if method then
- return method:lower(), uri, nil
+
+ msg.type = "request"
+ msg.request_method = method:lower()
+ msg.request_uri = uri
+ msg.http_version = tonumber( http_ver )
+ msg.headers = { }
+
+ -- We're done, next state is header parsing
+ return true, function( chunk )
+ return process_states['headers']( msg, chunk )
+ end
-- Is it a response?
else
- local code, message = line:match("^HTTP/[01]%.[019] ([0-9]+) ([^\r\n]+)\r?\n$")
+
+ local http_ver, code, message = chunk:match("^HTTP/([01]%.[019]) ([0-9]+) ([^\r\n]+)$")
-- Is a response
if code then
- return "response", code + 0, message
- -- Can't handle it
- else
- return nil
+ msg.type = "response"
+ msg.status_code = code
+ msg.status_message = message
+ msg.http_version = tonumber( http_ver )
+ msg.headers = { }
+
+ -- We're done, next state is header parsing
+ return true, function( chunk )
+ return process_states['headers']( msg, chunk )
+ end
end
end
end
+
+ -- Can't handle it
+ return nil, "Invalid HTTP message magic"
end
-- Extract headers from given string.
--- Returns a table of extracted headers and the remainder of the parsed data.
-function extract_headers( reader, tbl )
+process_states['headers'] = function( msg, chunk )
- local headers = tbl or { }
- local count = 0
-
- -- Iterate line by line
- for line in reader do
+ if chunk ~= nil then
-- Look for a valid header format
- local hdr, val = line:match( "^([A-Z][A-Za-z0-9%-_]+): +([^\r\n]+)\r?\n$" )
+ local hdr, val = chunk:match( "^([A-Za-z][A-Za-z0-9%-_]+): +(.+)$" )
if type(hdr) == "string" and hdr:len() > 0 and
type(val) == "string" and val:len() > 0
then
- count = count + line:len()
- headers[hdr] = val
+ msg.headers[hdr] = val
- elseif line:match("^\r?\n$") then
-
- return count + line:len(), headers
+ -- Valid header line, proceed
+ return true, nil
+ elseif #chunk == 0 then
+ -- Empty line, we won't accept data anymore
+ return false, nil
else
- -- junk data, don't add length
- return count, headers
+ -- Junk data
+ return nil, "Invalid HTTP header received"
end
+ else
+ return nil, "Unexpected EOF"
end
-
- return count, headers
end
--- Parse a http message
-function parse_message( data, filecb )
+--- Creates a ltn12 source from the given socket. The source will return it's
+-- data line by line with the trailing \r\n stripped of.
+-- @param sock Readable network socket
+-- @return Ltn12 source function
+function header_source( sock )
+ return ltn12.source.simplify( function()
- local reader = _linereader( data, HTTP_MAX_READBUF )
- local message = parse_message_header( reader )
+ local chunk, err, part = sock:receive("*l")
- if message then
- parse_message_body( reader, message, filecb )
- end
+ -- Line too long
+ if chunk == nil then
+ if err ~= "timeout" then
+ return nil, part
+ and "Line exceeds maximum allowed length"
+ or "Unexpected EOF"
+ else
+ return nil, err
+ end
- return message
-end
+ -- Line ok
+ elseif chunk ~= nil then
+ -- Strip trailing CR
+ chunk = chunk:gsub("\r$","")
--- Parse a http message header
-function parse_message_header( data )
+ return chunk, nil
+ end
+ end )
+end
- -- Create a line reader
- local reader = _linereader( data, HTTP_MAX_READBUF )
- local message = { }
+--- Decode a mime encoded http message body with multipart/form-data
+-- Content-Type. Stores all extracted data associated with its parameter name
+-- in the params table withing the given message object. Multiple parameter
+-- values are stored as tables, ordinary ones as strings.
+-- If an optional file callback function is given then it is feeded with the
+-- file contents chunk by chunk and only the extracted file name is stored
+-- within the params table. The callback function will be called subsequently
+-- with three arguments:
+-- o Table containing decoded (name, file) and raw (headers) mime header data
+-- o String value containing a chunk of the file data
+-- o Boolean which indicates wheather the current chunk is the last one (eof)
+-- @param src Ltn12 source function
+-- @param msg HTTP message object
+-- @param filecb File callback function (optional)
+-- @return Value indicating successful operation (not nil means "ok")
+-- @return String containing the error if unsuccessful
+-- @see parse_message_header
+function mimedecode_message_body( src, msg, filecb )
+
+ if msg and msg.env.CONTENT_TYPE then
+ msg.mime_boundary = msg.env.CONTENT_TYPE:match("^multipart/form%-data; boundary=(.+)$")
+ end
- -- Try to extract magic
- local method, arg1, arg2 = extract_magic( reader )
+ if not msg.mime_boundary then
+ return nil, "Invalid Content-Type found"
+ end
- -- Does it looks like a valid message?
- if method then
- message.request_method = method
- message.status_code = arg2 and arg1 or 200
- message.status_message = arg2 or nil
- message.request_uri = arg2 and nil or arg1
+ local tlen = 0
+ local inhdr = false
+ local field = nil
+ local store = nil
+ local lchunk = nil
- if method == "response" then
- message.type = "response"
- else
- message.type = "request"
- end
+ local function parse_headers( chunk, field )
- -- Parse headers?
- local hlen, hdrs = extract_headers( reader )
+ local stat
+ repeat
+ chunk, stat = chunk:gsub(
+ "^([A-Z][A-Za-z0-9%-_]+): +([^\r\n]+)\r\n",
+ function(k,v)
+ field.headers[k] = v
+ return ""
+ end
+ )
+ until stat == 0
- -- Valid headers?
- if hlen > 2 and type(hdrs) == "table" then
+ chunk, stat = chunk:gsub("^\r\n","")
- message.headers = hdrs
+ -- End of headers
+ if stat > 0 then
+ if field.headers["Content-Disposition"] then
+ if field.headers["Content-Disposition"]:match("^form%-data; ") then
+ field.name = field.headers["Content-Disposition"]:match('name="(.-)"')
+ field.file = field.headers["Content-Disposition"]:match('filename="(.+)"$')
+ end
+ end
- -- Process get parameters
- if ( method == "get" or method == "post" ) and
- message.request_uri:match("?")
- then
- message.params = urldecode_params( message.request_uri )
- else
- message.params = { }
+ if not field.headers["Content-Type"] then
+ field.headers["Content-Type"] = "text/plain"
end
- -- Populate common environment variables
- message.env = {
- CONTENT_LENGTH = hdrs['Content-Length'];
- CONTENT_TYPE = hdrs['Content-Type'];
- REQUEST_METHOD = message.request_method;
- REQUEST_URI = message.request_uri;
- SCRIPT_NAME = message.request_uri:gsub("?.+$","");
- SCRIPT_FILENAME = "" -- XXX implement me
- }
+ if field.name and field.file and filecb then
+ __initval( msg.params, field.name )
+ __appendval( msg.params, field.name, field.file )
- -- Populate HTTP_* environment variables
- for i, hdr in ipairs( {
- 'Accept',
- 'Accept-Charset',
- 'Accept-Encoding',
- 'Accept-Language',
- 'Connection',
- 'Cookie',
- 'Host',
- 'Referer',
- 'User-Agent',
- } ) do
- local var = 'HTTP_' .. hdr:upper():gsub("%-","_")
- local val = hdrs[hdr]
+ store = filecb
+ elseif field.name then
+ __initval( msg.params, field.name )
- message.env[var] = val
+ store = function( hdr, buf, eof )
+ __appendval( msg.params, field.name, buf )
+ end
+ else
+ store = nil
end
-
- return message
+ return chunk, true
end
- end
-end
+ return chunk, false
+ end
--- Parse a http message body
-function parse_message_body( reader, message, filecb )
+ local function snk( chunk )
- if type(message) == "table" then
- local env = message.env
+ tlen = tlen + ( chunk and #chunk or 0 )
- local clen = ( env.CONTENT_LENGTH or HTTP_MAX_CONTENT ) + 0
-
- -- Process post method
- if env.REQUEST_METHOD:lower() == "post" and env.CONTENT_TYPE then
+ if msg.env.CONTENT_LENGTH and tlen > tonumber(msg.env.CONTENT_LENGTH) + 2 then
+ return nil, "Message body size exceeds Content-Length"
+ end
- -- Is it multipart/form-data ?
- if env.CONTENT_TYPE:match("^multipart/form%-data") then
-
- -- Read multipart/mime data
- for k, v in pairs( mimedecode(
- reader,
- env.CONTENT_TYPE:match("boundary=(.+)"),
- filecb
- ) ) do
- message.params[k] = v
- end
+ if chunk and not lchunk then
+ lchunk = "\r\n" .. chunk
- -- Is it x-www-form-urlencoded?
- elseif env.CONTENT_TYPE:match('^application/x%-www%-form%-urlencoded') then
+ elseif lchunk then
+ local data = lchunk .. ( chunk or "" )
+ local spos, epos, found
- -- Read post data
- local post_data = ""
+ repeat
+ spos, epos = data:find( "\r\n--" .. msg.mime_boundary .. "\r\n", 1, true )
- for chunk, eol in reader do
+ if not spos then
+ spos, epos = data:find( "\r\n--" .. msg.mime_boundary .. "--\r\n", 1, true )
+ end
- post_data = post_data .. chunk
- -- Abort on eol or if maximum allowed size or content length is reached
- if eol or #post_data >= HTTP_MAX_CONTENT or #post_data > clen then
- break
- end
- end
+ if spos then
+ local predata = data:sub( 1, spos - 1 )
- -- Parse params
- for k, v in pairs( urldecode_params( post_data ) ) do
- message.params[k] = v
- end
+ if inhdr then
+ predata, eof = parse_headers( predata, field )
- -- Unhandled encoding
- -- If a file callback is given then feed it line by line, else
- -- store whole buffer in message.content
- else
+ if not eof then
+ return nil, "Invalid MIME section header"
+ elseif not field.name then
+ return nil, "Invalid Content-Disposition header"
+ end
+ end
- local len = 0
+ if store then
+ store( field, predata, true )
+ end
- for chunk in reader do
- len = len + #chunk
+ field = { headers = { } }
+ found = found or true
- -- We have a callback, feed it.
- if type(filecb) == "function" then
+ data, eof = parse_headers( data:sub( epos + 1, #data ), field )
+ inhdr = not eof
+ end
+ until not spos
- filecb( "_post", nil, chunk, false )
+ if found then
+ if #data > 78 then
+ lchunk = data:sub( #data - 78 + 1, #data )
+ data = data:sub( 1, #data - 78 )
- -- Append to .content buffer.
+ if store then
+ store( field, data, false )
else
- message.content =
- type(message.content) == "string"
- and message.content .. chunk
- or chunk
- end
-
- -- Abort if maximum allowed size or content length is reached
- if len >= HTTP_MAX_CONTENT or len >= clen then
- break
+ return nil, "Invalid MIME section header"
end
+ else
+ lchunk, data = data, nil
end
-
- -- Send eof to callback
- if type(filecb) == "function" then
- filecb( "_post", nil, "", true )
+ else
+ if inhdr then
+ lchunk, eof = parse_headers( data, field )
+ inhdr = not eof
+ else
+ store( field, lchunk, false )
+ lchunk, chunk = chunk, nil
end
end
end
+
+ return true
end
+
+ return ltn12.pump.all( src, snk )
end
+--- Decode an urlencoded http message body with application/x-www-urlencoded
+-- Content-Type. Stores all extracted data associated with its parameter name
+-- in the params table withing the given message object. Multiple parameter
+-- values are stored as tables, ordinary ones as strings.
+-- @param src Ltn12 source function
+-- @param msg HTTP message object
+-- @return Value indicating successful operation (not nil means "ok")
+-- @return String containing the error if unsuccessful
+-- @see parse_message_header
+function urldecode_message_body( src, msg )
--- Wrap given object into a line read iterator
-function _linereader( obj, bufsz )
+ local tlen = 0
+ local lchunk = nil
- bufsz = ( bufsz and bufsz >= 256 ) and bufsz or 256
+ local function snk( chunk )
- local __read = function() return nil end
- local __eof = function(x) return type(x) ~= "string" or #x == 0 end
+ tlen = tlen + ( chunk and #chunk or 0 )
- local _pos = 1
- local _buf = ""
- local _eof = nil
+ if msg.env.CONTENT_LENGTH and tlen > tonumber(msg.env.CONTENT_LENGTH) + 2 then
+ return nil, "Message body size exceeds Content-Length"
+ elseif tlen > HTTP_MAX_CONTENT then
+ return nil, "Message body size exceeds maximum allowed length"
+ end
- -- object is string
- if type(obj) == "string" then
+ if not lchunk and chunk then
+ lchunk = chunk
- __read = function() return obj:sub( _pos, _pos + bufsz - #_buf - 1 ) end
+ elseif lchunk then
+ local data = lchunk .. ( chunk or "&" )
+ local spos, epos
- -- object implements a receive() or read() function
- elseif type(obj) == "userdata" and ( type(obj.receive) == "function" or type(obj.read) == "function" ) then
+ repeat
+ spos, epos = data:find("^.-[;&]")
- if type(obj.read) == "function" then
- __read = function() return obj:read( bufsz - #_buf ) end
- else
- __read = function() return obj:receive( bufsz - #_buf ) end
- end
+ if spos then
+ local pair = data:sub( spos, epos - 1 )
+ local key = pair:match("^(.-)=")
+ local val = pair:match("=([^%s]*)%s*$")
- -- object is a function
- elseif type(obj) == "function" then
+ if key and #key > 0 then
+ __initval( msg.params, key )
+ __appendval( msg.params, key, val )
+ __finishval( msg.params, key, urldecode )
+ end
- return obj
+ data = data:sub( epos + 1, #data )
+ end
+ until not spos
- -- no usable data type
- else
+ lchunk = data
+ end
- -- dummy iterator
- return __read
+ return true
end
+ return ltn12.pump.all( src, snk )
+end
- -- generic block to line algorithm
- return function()
- if not _eof then
- local buffer = __read()
+--- Try to extract an http message header including information like protocol
+-- version, message headers and resulting CGI environment variables from the
+-- given ltn12 source.
+-- @param src Ltn12 source function
+-- @return HTTP message object
+-- @see parse_message_body
+function parse_message_header( src )
- if __eof( buffer ) then
- buffer = ""
- end
+ local ok = true
+ local msg = { }
+
+ local sink = ltn12.sink.simplify(
+ function( chunk )
+ return process_states['magic']( msg, chunk )
+ end
+ )
+
+ -- Pump input data...
+ while ok do
- _pos = _pos + #buffer
- buffer = _buf .. buffer
+ -- get data
+ ok, err = ltn12.pump.step( src, sink )
- local crlf, endpos = buffer:find("\r?\n")
+ -- error
+ if not ok and err then
+ return nil, err
+ -- eof
+ elseif not ok then
- if crlf then
- _buf = buffer:sub( endpos + 1, #buffer )
- return buffer:sub( 1, endpos ), true
+ -- Process get parameters
+ if ( msg.request_method == "get" or msg.request_method == "post" ) and
+ msg.request_uri:match("?")
+ then
+ msg.params = urldecode_params( msg.request_uri )
else
- -- check for eof
- _eof = __eof( buffer )
+ msg.params = { }
+ end
- -- clear overflow buffer
- _buf = ""
+ -- Populate common environment variables
+ msg.env = {
+ CONTENT_LENGTH = msg.headers['Content-Length'];
+ CONTENT_TYPE = msg.headers['Content-Type'] or msg.headers['Content-type'];
+ REQUEST_METHOD = msg.request_method:upper();
+ REQUEST_URI = msg.request_uri;
+ SCRIPT_NAME = msg.request_uri:gsub("?.+$","");
+ SCRIPT_FILENAME = ""; -- XXX implement me
+ SERVER_PROTOCOL = "HTTP/" .. string.format("%.1f", msg.http_version);
+ QUERY_STRING = msg.request_uri:match("?")
+ and msg.request_uri:gsub("^.+?","") or ""
+ }
+
+ -- Populate HTTP_* environment variables
+ for i, hdr in ipairs( {
+ 'Accept',
+ 'Accept-Charset',
+ 'Accept-Encoding',
+ 'Accept-Language',
+ 'Connection',
+ 'Cookie',
+ 'Host',
+ 'Referer',
+ 'User-Agent',
+ } ) do
+ local var = 'HTTP_' .. hdr:upper():gsub("%-","_")
+ local val = msg.headers[hdr]
- return buffer, false
+ msg.env[var] = val
end
+ end
+ end
+
+ return msg
+end
+
+--- Try to extract and decode a http message body from the given ltn12 source.
+-- This function will examine the Content-Type within the given message object
+-- to select the appropriate content decoder.
+-- Currently the application/x-www-urlencoded and application/form-data
+-- mime types are supported. If the encountered content encoding can't be
+-- handled then the whole message body will be stored unaltered as "content"
+-- property within the given message object.
+-- @param src Ltn12 source function
+-- @param msg HTTP message object
+-- @param filecb File data callback (optional, see mimedecode_message_body())
+-- @return Value indicating successful operation (not nil means "ok")
+-- @return String containing the error if unsuccessful
+-- @see parse_message_header
+function parse_message_body( src, msg, filecb )
+ -- Is it multipart/mime ?
+ if msg.env.REQUEST_METHOD == "POST" and msg.env.CONTENT_TYPE and
+ msg.env.CONTENT_TYPE:match("^multipart/form%-data")
+ then
+
+ return mimedecode_message_body( src, msg, filecb )
+
+ -- Is it application/x-www-form-urlencoded ?
+ elseif msg.env.REQUEST_METHOD == "POST" and msg.env.CONTENT_TYPE and
+ msg.env.CONTENT_TYPE:match("^application/x%-www%-form%-urlencoded")
+ then
+ return urldecode_message_body( src, msg, filecb )
+
+
+ -- Unhandled encoding
+ -- If a file callback is given then feed it chunk by chunk, else
+ -- store whole buffer in message.content
+ else
+
+ local sink
+
+ -- If we have a file callback then feed it
+ if type(filecb) == "function" then
+ sink = filecb
+
+ -- ... else append to .content
else
- return nil
+ msg.content = ""
+ msg.content_length = 0
+
+ sink = function( chunk, err )
+ if chunk then
+ if ( msg.content_length + #chunk ) <= HTTP_MAX_CONTENT then
+ msg.content = msg.content .. chunk
+ msg.content_length = msg.content_length + #chunk
+ return true
+ else
+ return nil, "POST data exceeds maximum allowed length"
+ end
+ end
+ return true
+ end
end
+
+ -- Pump data...
+ while true do
+ local ok, err = ltn12.pump.step( src, sink )
+
+ if not ok and err then
+ return nil, err
+ elseif not err then
+ return true
+ end
+ end
+
+ return true
end
end
+
+--- Table containing human readable messages for several http status codes.
+-- @class table
+statusmsg = {
+ [200] = "OK",
+ [206] = "Partial Content",
+ [301] = "Moved Permanently",
+ [302] = "Found",
+ [304] = "Not Modified",
+ [400] = "Bad Request",
+ [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",
+}