luci/libs/web/luasrc/http/protocol.lua

509 lines
12 KiB
Lua

--[[
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
$Id$
]]--
module("luci.http.protocol", package.seeall)
require("luci.util")
HTTP_MAX_CONTENT = 1048576 -- 1 MB
HTTP_DEFAULT_CTYPE = "text/html" -- default content type
HTTP_DEFAULT_VERSION = "1.0" -- HTTP default version
-- Decode an urlencoded string.
-- Returns the decoded value.
function urldecode( str )
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 )
end
return str
end
-- 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 = { }
if url:find("?") then
url = url:gsub( "^.+%?([^?]+)", "%1" )
end
for i, pair in ipairs(luci.util.split( url, "[&;]+", nil, true )) do
-- find key and value
local key = urldecode( pair:match("^([^=]+)") )
local val = urldecode( pair:match("^[^=]+=(.+)$") )
-- store
if type(key) == "string" and key:len() > 0 then
if type(val) ~= "string" then val = "" end
if not params[key] then
params[key] = val
elseif type(params[key]) ~= "table" then
params[key] = { params[key], val }
else
table.insert( params[key], val )
end
end
end
return params
end
-- Encode given string in urlencoded format.
-- Returns the encoded string.
function urlencode( str )
local function __chrenc( chr )
return string.format(
"%%%02x", string.byte( chr )
)
end
if type(str) == "string" then
str = str:gsub(
"([^a-zA-Z0-9$_%-%.+!*'(),])",
__chrenc
)
end
return str
end
-- Encode given table to urlencoded string.
-- Returns the encoded string.
function urlencode_params( tbl )
local enc = ""
for k, v in pairs(tbl) do
enc = enc .. ( enc and "&" or "" ) ..
urlencode(k) .. "=" ..
urlencode(v)
end
return enc
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 )
-- 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 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
-- Append date to buffer
buffer = buffer .. line
end
end
return params
end
-- 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 )
for line in reader do
-- Is it a request?
local method, uri = line:match("^([A-Z]+) ([^ ]+) HTTP/[01]%.[019]\r?\n$")
-- Yup, it is
if method then
return method:lower(), uri, nil
-- Is it a response?
else
local code, message = line:match("^HTTP/[01]%.[019] ([0-9]+) ([^\r\n]+)\r?\n$")
-- Is a response
if code then
return "response", code + 0, message
-- Can't handle it
else
return nil
end
end
end
end
-- Extract headers from given string.
-- Returns a table of extracted headers and the remainder of the parsed data.
function extract_headers( reader, tbl )
local headers = tbl or { }
local count = 0
-- Iterate line by line
for line in reader do
-- Look for a valid header format
local hdr, val = line:match( "^([A-Z][A-Za-z0-9%-_]+): +([^\r\n]+)\r?\n$" )
if type(hdr) == "string" and hdr:len() > 0 and
type(val) == "string" and val:len() > 0
then
count = count + line:len()
headers[hdr] = val
elseif line:match("^\r?\n$") then
return count + line:len(), headers
else
-- junk data, don't add length
return count, headers
end
end
return count, headers
end
-- Parse a http message
function parse_message( data, filecb )
-- Create a line reader
local reader = _linereader( data )
local message = { }
-- Try to extract magic
local method, arg1, arg2 = extract_magic( reader )
-- 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
if method == "response" then
message.type = "response"
else
message.type = "request"
end
-- Parse headers?
local hlen, hdrs = extract_headers( reader )
-- Valid headers?
if hlen > 2 and type(hdrs) == "table" then
message.headers = hdrs
-- Get content
local clen = ( hdrs['Content-Length'] or HTTP_MAX_CONTENT ) + 0
-- 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 = { }
end
-- Process post method
if method == "post" and hdrs['Content-Type'] then
-- Is it multipart/form-data ?
if hdrs['Content-Type']:match("^multipart/form%-data") then
for k, v in pairs( mimedecode(
reader,
hdrs['Content-Type']:match("boundary=(.+)"),
filecb
) ) do
message.params[k] = v
end
-- Is it x-www-urlencoded?
elseif hdrs['Content-Type'] == 'application/x-www-urlencoded' then
-- XXX: readline isn't the best solution here
for chunk in reader do
for k, v in pairs( urldecode_params( chunk ) ) do
message.params[k] = v
end
-- XXX: unreliable (undefined line length)
if clen + chunk:len() >= HTTP_MAX_CONTENT then
break
end
clen = clen + chunk:len()
end
-- Unhandled encoding
-- If a file callback is given then feed it line by line, else
-- store whole buffer in message.content
else
for chunk in reader do
-- We have a callback, feed it.
if type(filecb) == "function" then
filecb( "_post", nil, chunk, false )
-- Append to .content buffer.
else
message.content =
type(message.content) == "string"
and message.content .. chunk
or chunk
end
-- XXX: unreliable
if clen + chunk:len() >= HTTP_MAX_CONTENT then
break
end
clen = clen + chunk:len()
end
-- Send eof to callback
if type(filecb) == "function" then
filecb( "_post", nil, "", true )
end
end
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
}
-- 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]
message.env[var] = val
end
return message
end
end
end
function _linereader( obj )
-- object is string
if type(obj) == "string" then
return obj:gmatch( "[^\r\n]*\r?\n" )
-- object is a function
elseif type(obj) == "function" then
return obj
-- object is a table and implements a readline() function
elseif type(obj) == "table" and type(obj.readline) == "function" then
return obj.readline
-- object is a table and has a lines property
elseif type(obj) == "table" and obj.lines then
-- decide wheather to use "lines" as function or table
local _lns = ( type(obj.lines) == "function" ) and obj.lines() or obj.lines
local _pos = 1
return function()
if _pos <= #_lns then
_pos = _pos + 1
return _lns[_pos]
end
end
-- no usable data type
else
-- dummy iterator
return function()
return nil
end
end
end