net/http/parser.lua

   1 local tonumber = tonumber;
   2 local assert = assert;
   3 local url_parse = require "socket.url".parse;
   4 local urldecode = require "util.http".urldecode;
   5
   6 local function preprocess_path(path)
   7         path = urldecode((path:gsub("//+", "/")));
   8         if path:sub(1,1) ~= "/" then
   9                 path = "/"..path;
  10         end
  11         local level = 0;
  12         for component in path:gmatch("([^/]+)/") do
  13                 if component == ".." then
  14                         level = level - 1;
  15                 elseif component ~= "." then
  16                         level = level + 1;
  17                 end
  18                 if level < 0 then
  19                         return nil;
  20                 end
  21         end
  22         return path;
  23 end
  24
  25 local httpstream = {};
  26
  27 function httpstream.new(success_cb, error_cb, parser_type, options_cb)
  28         local client = true;
  29         if not parser_type or parser_type == "server" then client = false; else assert(parser_type == "client", "Invalid parser type"); end
  30         local buf = "";
  31         local chunked, chunk_size, chunk_start;
  32         local state = nil;
  33         local packet;
  34         local len;
  35         local have_body;
  36         local error;
  37         return {
  38                 feed = function(self, data)
  39                         if error then return nil, "parse has failed"; end
  40                         if not data then -- EOF
  41                                 if state and client and not len then -- reading client body until EOF
  42                                         packet.body = buf;
  43                                         success_cb(packet);
  44                                 elseif buf ~= "" then -- unexpected EOF
  45                                         error = true; return error_cb();
  46                                 end
  47                                 return;
  48                         end
  49                         buf = buf..data;
  50                         while #buf > 0 do
  51                                 if state == nil then -- read request
  52                                         local index = buf:find("\r\n\r\n", nil, true);
  53                                         if not index then return; end -- not enough data
  54                                         local method, path, httpversion, status_code, reason_phrase;
  55                                         local first_line;
  56                                         local headers = {};
  57                                         for line in buf:sub(1,index+1):gmatch("([^\r\n]+)\r\n") do -- parse request
  58                                                 if first_line then
  59                                                         local key, val = line:match("^([^%s:]+): *(.*)$");
  60                                                         if not key then error = true; return error_cb("invalid-header-line"); end -- TODO handle multi-line and invalid headers
  61                                                         key = key:lower();
  62                                                         headers[key] = headers[key] and headers[key]..","..val or val;
  63                                                 else
  64                                                         first_line = line;
  65                                                         if client then
  66                                                                 httpversion, status_code, reason_phrase = line:match("^HTTP/(1%.[01]) (%d%d%d) (.*)$");
  67                                                                 status_code = tonumber(status_code);
  68                                                                 if not status_code then error = true; return error_cb("invalid-status-line"); end
  69                                                                 have_body = not
  70                                                                          ( (options_cb and options_cb().method == "HEAD")
  71                                                                         or (status_code == 204 or status_code == 304 or status_code == 301)
  72                                                                         or (status_code >= 100 and status_code < 200) );
  73                                                         else
  74                                                                 method, path, httpversion = line:match("^(%w+) (%S+) HTTP/(1%.[01])$");
  75                                                                 if not method then error = true; return error_cb("invalid-status-line"); end
  76                                                         end
  77                                                 end
  78                                         end
  79                                         if not first_line then error = true; return error_cb("invalid-status-line"); end
  80                                         chunked = have_body and headers["transfer-encoding"] == "chunked";
  81                                         len = tonumber(headers["content-length"]); -- TODO check for invalid len
  82                                         if client then
  83                                                 -- FIXME handle '100 Continue' response (by skipping it)
  84                                                 if not have_body then len = 0; end
  85                                                 packet = {
  86                                                         code = status_code;
  87                                                         httpversion = httpversion;
  88                                                         headers = headers;
  89                                                         body = have_body and "" or nil;
  90                                                         -- COMPAT the properties below are deprecated
  91                                                         responseversion = httpversion;
  92                                                         responseheaders = headers;
  93                                                 };
  94                                         else
  95                                                 local parsed_url;
  96                                                 if path:byte() == 47 then -- starts with /
  97                                                         local _path, _query = path:match("([^?]*).?(.*)");
  98                                                         if _query == "" then _query = nil; end
  99                                                         parsed_url = { path = _path, query = _query };
 100                                                 else
 101                                                         parsed_url = url_parse(path);
 102                                                         if not(parsed_url and parsed_url.path) then error = true; return error_cb("invalid-url"); end
 103                                                 end
 104                                                 path = preprocess_path(parsed_url.path);
 105                                                 headers.host = parsed_url.host or headers.host;
 106
 107                                                 len = len or 0;
 108                                                 packet = {
 109                                                         method = method;
 110                                                         url = parsed_url;
 111                                                         path = path;
 112                                                         httpversion = httpversion;
 113                                                         headers = headers;
 114                                                         body = nil;
 115                                                 };
 116                                         end
 117                                         buf = buf:sub(index + 4);
 118                                         state = true;
 119                                 end
 120                                 if state then -- read body
 121                                         if client then
 122                                                 if chunked then
 123                                                         if not buf:find("\r\n", nil, true) then
 124                                                                 return;
 125                                                         end -- not enough data
 126                                                         if not chunk_size then
 127                                                                 chunk_size, chunk_start = buf:match("^(%x+)[^\r\n]*\r\n()");
 128                                                                 chunk_size = chunk_size and tonumber(chunk_size, 16);
 129                                                                 if not chunk_size then error = true; return error_cb("invalid-chunk-size"); end
 130                                                         end
 131                                                         if chunk_size == 0 and buf:find("\r\n\r\n", chunk_start-2, true) then
 132                                                                 state, chunk_size = nil, nil;
 133                                                                 buf = buf:gsub("^.-\r\n\r\n", ""); -- This ensure extensions and trailers are stripped
 134                                                                 success_cb(packet);
 135                                                         elseif #buf - chunk_start + 2 >= chunk_size then -- we have a chunk
 136                                                                 packet.body = packet.body..buf:sub(chunk_start, chunk_start + (chunk_size-1));
 137                                                                 buf = buf:sub(chunk_start + chunk_size + 2);
 138                                                                 chunk_size, chunk_start = nil, nil;
 139                                                         else -- Partial chunk remaining
 140                                                                 break;
 141                                                         end
 142                                                 elseif len and #buf >= len then
 143                                                        if packet.code == 101 then
 144                                                                packet.body, buf = buf, ""
 145                                                        else
 146                                                                packet.body, buf = buf:sub(1, len), buf:sub(len + 1);
 147                                                        end
 148                                                         state = nil; success_cb(packet);
 149                                                 else
 150                                                         break;
 151                                                 end
 152                                         elseif #buf >= len then
 153                                                 packet.body, buf = buf:sub(1, len), buf:sub(len + 1);
 154                                                 state = nil; success_cb(packet);
 155                                         else
 156                                                 break;
 157                                         end
 158                                 end
 159                         end
 160                 end;
 161         };
 162 end
 163
 164 return httpstream;