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