plugins/mod_http_files.lua

   1 -- Prosody IM
   2 -- Copyright (C) 2008-2010 Matthew Wild
   3 -- Copyright (C) 2008-2010 Waqas Hussain
   4 --
   5 -- This project is MIT/X11 licensed. Please see the
   6 -- COPYING file in the source package for more information.
   7 --
   8
   9 module:depends("http");
  10 local server = require"net.http.server";
  11 local lfs = require "lfs";
  12
  13 local os_date = os.date;
  14 local open = io.open;
  15 local stat = lfs.attributes;
  16 local build_path = require"socket.url".build_path;
  17 local path_sep = package.config:sub(1,1);
  18
  19 local base_path = module:get_option_string("http_files_dir", module:get_option_string("http_path"));
  20 local cache_size = module:get_option_number("http_files_cache_size", 128);
  21 local cache_max_file_size = module:get_option_number("http_files_cache_max_file_size", 4096);
  22 local dir_indices = module:get_option("http_index_files", { "index.html", "index.htm" });
  23 local directory_index = module:get_option_boolean("http_dir_listing");
  24
  25 local mime_map = module:shared("/*/http_files/mime").types;
  26 if not mime_map then
  27         mime_map = {
  28                 html = "text/html", htm = "text/html",
  29                 xml = "application/xml",
  30                 txt = "text/plain",
  31                 css = "text/css",
  32                 js = "application/javascript",
  33                 png = "image/png",
  34                 gif = "image/gif",
  35                 jpeg = "image/jpeg", jpg = "image/jpeg",
  36                 svg = "image/svg+xml",
  37         };
  38         module:shared("/*/http_files/mime").types = mime_map;
  39
  40         local mime_types, err = open(module:get_option_string("mime_types_file", "/etc/mime.types"),"r");
  41         if mime_types then
  42                 local mime_data = mime_types:read("*a");
  43                 mime_types:close();
  44                 setmetatable(mime_map, {
  45                         __index = function(t, ext)
  46                                 local typ = mime_data:match("\n(%S+)[^\n]*%s"..(ext:lower()).."%s") or "application/octet-stream";
  47                                 t[ext] = typ;
  48                                 return typ;
  49                         end
  50                 });
  51         end
  52 end
  53
  54 local forbidden_chars_pattern = "[/%z]";
  55 if prosody.platform == "windows" then
  56         forbidden_chars_pattern = "[/%z\001-\031\127\"*:<>?|]"
  57 end
  58
  59 local urldecode = require "util.http".urldecode;
  60 function sanitize_path(path)
  61         if not path then return end
  62         local out = {};
  63
  64         local c = 0;
  65         for component in path:gmatch("([^/]+)") do
  66                 component = urldecode(component);
  67                 if component:find(forbidden_chars_pattern) then
  68                         return nil;
  69                 elseif component == ".." then
  70                         if c <= 0 then
  71                                 return nil;
  72                         end
  73                         out[c] = nil;
  74                         c = c - 1;
  75                 elseif component ~= "." then
  76                         c = c + 1;
  77                         out[c] = component;
  78                 end
  79         end
  80         if path:sub(-1,-1) == "/" then
  81                 out[c+1] = "";
  82         end
  83         return "/"..table.concat(out, "/");
  84 end
  85
  86 local cache = require "util.cache".new(cache_size);
  87
  88 function serve(opts)
  89         if type(opts) ~= "table" then -- assume path string
  90                 opts = { path = opts };
  91         end
  92         local base_path = opts.path;
  93         local dir_indices = opts.index_files or dir_indices;
  94         local directory_index = opts.directory_index;
  95         local function serve_file(event, path)
  96                 local request, response = event.request, event.response;
  97                 local sanitized_path = sanitize_path(path);
  98                 if path and not sanitized_path then
  99                         return 400;
 100                 end
 101                 path = sanitized_path;
 102                 local orig_path = sanitize_path(request.path);
 103                 local full_path = base_path .. (path or ""):gsub("/", path_sep);
 104                 local attr = stat(full_path:match("^.*[^\\/]")); -- Strip trailing path separator because Windows
 105                 if not attr then
 106                         return 404;
 107                 end
 108
 109                 local request_headers, response_headers = request.headers, response.headers;
 110
 111                 local last_modified = os_date('!%a, %d %b %Y %H:%M:%S GMT', attr.modification);
 112                 response_headers.last_modified = last_modified;
 113
 114                 local etag = ('"%02x-%x-%x-%x"'):format(attr.dev or 0, attr.ino or 0, attr.size or 0, attr.modification or 0);
 115                 response_headers.etag = etag;
 116
 117                 local if_none_match = request_headers.if_none_match
 118                 local if_modified_since = request_headers.if_modified_since;
 119                 if etag == if_none_match
 120                 or (not if_none_match and last_modified == if_modified_since) then
 121                         return 304;
 122                 end
 123
 124                 local data = cache:get(orig_path);
 125                 if data and data.etag == etag then
 126                         response_headers.content_type = data.content_type;
 127                         data = data.data;
 128                 elseif attr.mode == "directory" and path then
 129                         if full_path:sub(-1) ~= "/" then
 130                                 local path = { is_absolute = true, is_directory = true };
 131                                 for dir in orig_path:gmatch("[^/]+") do path[#path+1]=dir; end
 132                                 response_headers.location = build_path(path);
 133                                 return 301;
 134                         end
 135                         for i=1,#dir_indices do
 136                                 if stat(full_path..dir_indices[i], "mode") == "file" then
 137                                         return serve_file(event, path..dir_indices[i]);
 138                                 end
 139                         end
 140
 141                         if directory_index then
 142                                 data = server._events.fire_event("directory-index", { path = request.path, full_path = full_path });
 143                         end
 144                         if not data then
 145                                 return 403;
 146                         end
 147                         cache[orig_path] = { data = data, content_type = mime_map.html; etag = etag; };
 148                         response_headers.content_type = mime_map.html;
 149
 150                 else
 151                         local f, err = open(full_path, "rb");
 152                         if not f then
 153                                 module:log("debug", "Could not open %s. Error was %s", full_path, err);
 154                                 return 403;
 155                         end
 156                         local ext = full_path:match("%.([^./]+)$");
 157                         local content_type = ext and mime_map[ext];
 158                         response_headers.content_type = content_type;
 159                         if attr.size > cache_max_file_size then
 160                                 response_headers.content_length = attr.size;
 161                                 module:log("debug", "%d > cache_max_file_size", attr.size);
 162                                 return response:send_file(f);
 163                         else
 164                                 data = f:read("*a");
 165                                 f:close();
 166                         end
 167                         cache:set(orig_path, { data = data; content_type = content_type; etag = etag });
 168                 end
 169
 170                 return response:send(data);
 171         end
 172
 173         return serve_file;
 174 end
 175
 176 function wrap_route(routes)
 177         for route,handler in pairs(routes) do
 178                 if type(handler) ~= "function" then
 179                         routes[route] = serve(handler);
 180                 end
 181         end
 182         return routes;
 183 end
 184
 185 if base_path then
 186         module:provides("http", {
 187                 route = {
 188                         ["GET /*"] = serve {
 189                                 path = base_path;
 190                                 directory_index = directory_index;
 191                         }
 192                 };
 193         });
 194 else
 195         module:log("debug", "http_files_dir not set, assuming use by some other module");
 196 end
 197