libs/lucid-http/luasrc/lucid/http/handler/file.lua

   1 --[[
   2
   3 HTTP server implementation for LuCI - file handler
   4 (c) 2008 Steven Barth <steven@midlink.org>
   5 (c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
   6
   7 Licensed under the Apache License, Version 2.0 (the "License");
   8 you may not use this file except in compliance with the License.
   9 You may obtain a copy of the License at
  10
  11         http://www.apache.org/licenses/LICENSE-2.0
  12
  13 $Id$
  14
  15 ]]--
  16
  17 local ipairs, type, tonumber = ipairs, type, tonumber
  18 local os = require "os"
  19 local nixio = require "nixio", require "nixio.util"
  20 local fs = require "nixio.fs"
  21 local util = require "luci.util"
  22 local ltn12 = require "luci.ltn12"
  23 local srv = require "luci.lucid.http.server"
  24 local string = require "string"
  25
  26 local prot = require "luci.http.protocol"
  27 local date = require "luci.http.protocol.date"
  28 local mime = require "luci.http.protocol.mime"
  29 local cond = require "luci.http.protocol.conditionals"
  30
  31 module "luci.lucid.http.handler.file"
  32
  33 Simple = util.class(srv.Handler)
  34
  35 function Simple.__init__(self, name, docroot, options)
  36         srv.Handler.__init__(self, name)
  37         self.docroot = docroot
  38         self.realdocroot = fs.realpath(self.docroot)
  39
  40         options = options or {}
  41         self.dirlist = not options.noindex
  42         self.error404 = options.error404
  43 end
  44
  45 function Simple.parse_range(self, request, size)
  46         if not request.headers.Range then
  47                 return true
  48         end
  49
  50         local from, to = request.headers.Range:match("bytes=([0-9]*)-([0-9]*)")
  51         if not (from or to) then
  52                 return true
  53         end
  54
  55         from, to = tonumber(from), tonumber(to)
  56         if not (from or to) then
  57                 return true
  58         elseif not from then
  59                 from, to = size - to, size - 1
  60         elseif not to then
  61                 to = size - 1
  62         end
  63
  64         -- Not satisfiable
  65         if from >= size then
  66                 return false
  67         end
  68
  69         -- Normalize
  70         if to >= size then
  71                 to = size - 1
  72         end
  73
  74         local range = "bytes " .. from .. "-" .. to .. "/" .. size
  75         return from, (1 + to - from), range
  76 end
  77
  78 function Simple.getfile(self, uri)
  79         if not self.realdocroot then
  80                 self.realdocroot = fs.realpath(self.docroot)
  81         end
  82         local file = fs.realpath(self.docroot .. uri)
  83         if not file or file:sub(1, #self.realdocroot) ~= self.realdocroot then
  84                 return uri
  85         end
  86         return file, fs.stat(file)
  87 end
  88
  89 function Simple.handle_GET(self, request)
  90         local file, stat = self:getfile(prot.urldecode(request.env.PATH_INFO, true))
  91
  92         if stat then
  93                 if stat.type == "reg" then
  94
  95                         -- Generate Entity Tag
  96                         local etag = cond.mk_etag( stat )
  97
  98                         -- Check conditionals
  99                         local ok, code, hdrs
 100
 101                         ok, code, hdrs = cond.if_modified_since( request, stat )
 102                         if ok then
 103                                 ok, code, hdrs = cond.if_match( request, stat )
 104                                 if ok then
 105                                         ok, code, hdrs = cond.if_unmodified_since( request, stat )
 106                                         if ok then
 107                                                 ok, code, hdrs = cond.if_none_match( request, stat )
 108                                                 if ok then
 109                                                         local f, err = nixio.open(file)
 110
 111                                                         if f then
 112                                                                 local code = 200
 113                                                                 local o, s, r = self:parse_range(request, stat.size)
 114
 115                                                                 if not o then
 116                                                                         return self:failure(416, "Invalid Range")
 117                                                                 end
 118
 119                                                                 local headers = {
 120                                                                         ["Last-Modified"]  = date.to_http( stat.mtime ),
 121                                                                         ["Content-Type"]   = mime.to_mime( file ),
 122                                                                         ["ETag"]           = etag,
 123                                                                         ["Accept-Ranges"]  = "bytes",
 124                                                                 }
 125
 126                                                                 if o == true then
 127                                                                         s = stat.size
 128                                                                 else
 129                                                                         code = 206
 130                                                                         headers["Content-Range"] = r
 131                                                                         f:seek(o)
 132                                                                 end
 133
 134                                                                 headers["Content-Length"] = s
 135
 136                                                                 -- Send Response
 137                                                                 return code, headers, srv.IOResource(f, s)
 138                                                         else
 139                                                                 return self:failure( 403, err:gsub("^.+: ", "") )
 140                                                         end
 141                                                 else
 142                                                         return code, hdrs
 143                                                 end
 144                                         else
 145                                                 return code, hdrs
 146                                         end
 147                                 else
 148                                         return code, hdrs
 149                                 end
 150                         else
 151                                 return code, hdrs
 152                         end
 153
 154                 elseif stat.type == "dir" then
 155
 156                         local ruri = request.env.REQUEST_URI:gsub("/$", "")
 157                         local duri = prot.urldecode( ruri, true )
 158                         local root = self.docroot
 159
 160                         -- check for index files
 161                         local index_candidates = {
 162                                 "index.html", "index.htm", "default.html", "default.htm",
 163                                 "index.txt", "default.txt"
 164                         }
 165
 166                         -- try to find an index file and redirect to it
 167                         for i, candidate in ipairs( index_candidates ) do
 168                                 local istat = fs.stat(
 169                                         root .. "/" .. duri .. "/" .. candidate
 170                                 )
 171
 172                                 if istat ~= nil and istat.type == "reg" then
 173                                         return 302, { Location = ruri .. "/" .. candidate }
 174                                 end
 175                         end
 176
 177
 178                         local html = string.format(
 179                                 '<?xml version="1.0" encoding="utf-8"?>\n' ..
 180                                 '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" '     ..
 181                                         '"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">\n'..
 182                                 '<html xmlns="http://www.w3.org/1999/xhtml" '                           ..
 183                                         'xml:lang="en" lang="en">\n'                                                    ..
 184                                 '<head>\n'                                                                                                      ..
 185                                 '<title>Index of %s/</title>\n'                                                         ..
 186                                 '<style type="text/css">\n'                                                                     ..
 187                                         'body { color:#000000 } '                                                               ..
 188                                         'li { border-bottom:1px dotted #CCCCCC; padding:3px } ' ..
 189                                         'small { font-size:60%%; color:#333333 } '                              ..
 190                                         'p { margin:0 }'                                                                                ..
 191                                         '\n</style></head><body><h1>Index of %s/</h1><hr /><ul>'..
 192                                         '<li><p><a href="%s/../">../</a> '                                              ..
 193                                         '<small>(parent directory)</small><br />'                                               ..
 194                                         '<small></small></li>',
 195                                         duri, duri, ruri
 196                         )
 197
 198                         local entries = fs.dir( file )
 199
 200                         if type(entries) == "function" then
 201                                 for i, e in util.vspairs(nixio.util.consume(entries)) do
 202                                         local estat = fs.stat( file .. "/" .. e )
 203
 204                                         if estat.type == "dir" then
 205                                                 html = html .. string.format(
 206                                                         '<li><p><a href="%s/%s/">%s/</a> '           ..
 207                                                         '<small>(directory)</small><br />'           ..
 208                                                         '<small>Changed: %s</small></li>',
 209                                                                 ruri, prot.urlencode( e ), e,
 210                                                                 date.to_http( estat.mtime )
 211                                                 )
 212                                         else
 213                                                 html = html .. string.format(
 214                                                         '<li><p><a href="%s/%s">%s</a> '             ..
 215                                                         '<small>(%s)</small><br />'                  ..
 216                                                         '<small>Size: %i Bytes | '                   ..
 217                                                                 'Changed: %s</small></li>',
 218                                                                 ruri, prot.urlencode( e ), e,
 219                                                                 mime.to_mime( e ),
 220                                                                 estat.size, date.to_http( estat.mtime )
 221                                                 )
 222                                         end
 223                                 end
 224
 225                                 html = html .. '</ul><hr /><address>LuCId-HTTPd' ..
 226                                         '</address></body></html>'
 227
 228                                 return 200, {
 229                                                 ["Date"]         = date.to_http( os.time() );
 230                                                 ["Content-Type"] = "text/html; charset=utf-8";
 231                                         }, ltn12.source.string(html)
 232                         else
 233                                 return self:failure(403, "Permission denied")
 234                         end
 235                 else
 236                         return self:failure(403, "Unable to transmit " .. stat.type .. " " .. file)
 237                 end
 238         else
 239                 if self.error404 then
 240                         return 302, { Location = self.error404 }
 241                 else
 242                         return self:failure(404, "No such file: " .. file)
 243                 end
 244         end
 245 end
 246
 247 function Simple.handle_HEAD(self, ...)
 248         local stat, head = self:handle_GET(...)
 249         return stat, head
 250 end