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Edit File: filehandler.rb
# # filehandler.rb -- FileHandler Module # # Author: IPR -- Internet Programming with Ruby -- writers # Copyright (c) 2001 TAKAHASHI Masayoshi, GOTOU Yuuzou # Copyright (c) 2003 Internet Programming with Ruby writers. All rights # reserved. # # $IPR: filehandler.rb,v 1.44 2003/06/07 01:34:51 gotoyuzo Exp $ require 'thread' require 'time' require 'webrick/htmlutils' require 'webrick/httputils' require 'webrick/httpstatus' module WEBrick module HTTPServlet class DefaultFileHandler < AbstractServlet def initialize(server, local_path) super(server, local_path) @local_path = local_path end def do_GET(req, res) st = File::stat(@local_path) mtime = st.mtime res['etag'] = sprintf("%x-%x-%x", st.ino, st.size, st.mtime.to_i) if not_modified?(req, res, mtime, res['etag']) res.body = '' raise HTTPStatus::NotModified elsif req['range'] make_partial_content(req, res, @local_path, st.size) raise HTTPStatus::PartialContent else mtype = HTTPUtils::mime_type(@local_path, @config[:MimeTypes]) res['content-type'] = mtype res['content-length'] = st.size res['last-modified'] = mtime.httpdate res.body = open(@local_path, "rb") end end def not_modified?(req, res, mtime, etag) if ir = req['if-range'] begin if Time.httpdate(ir) >= mtime return true end rescue if HTTPUtils::split_header_value(ir).member?(res['etag']) return true end end end if (ims = req['if-modified-since']) && Time.parse(ims) >= mtime return true end if (inm = req['if-none-match']) && HTTPUtils::split_header_value(inm).member?(res['etag']) return true end return false end def make_partial_content(req, res, filename, filesize) mtype = HTTPUtils::mime_type(filename, @config[:MimeTypes]) unless ranges = HTTPUtils::parse_range_header(req['range']) raise HTTPStatus::BadRequest, "Unrecognized range-spec: \"#{req['range']}\"" end open(filename, "rb"){|io| if ranges.size > 1 time = Time.now boundary = "#{time.sec}_#{time.usec}_#{Process::pid}" body = '' ranges.each{|range| first, last = prepare_range(range, filesize) next if first < 0 io.pos = first content = io.read(last-first+1) body << "--" << boundary << CRLF body << "Content-Type: #{mtype}" << CRLF body << "Content-Range: bytes #{first}-#{last}/#{filesize}" << CRLF body << CRLF body << content body << CRLF } raise HTTPStatus::RequestRangeNotSatisfiable if body.empty? body << "--" << boundary << "--" << CRLF res["content-type"] = "multipart/byteranges; boundary=#{boundary}" res.body = body elsif range = ranges[0] first, last = prepare_range(range, filesize) raise HTTPStatus::RequestRangeNotSatisfiable if first < 0 if last == filesize - 1 content = io.dup content.pos = first else io.pos = first content = io.read(last-first+1) end res['content-type'] = mtype res['content-range'] = "bytes #{first}-#{last}/#{filesize}" res['content-length'] = last - first + 1 res.body = content else raise HTTPStatus::BadRequest end } end def prepare_range(range, filesize) first = range.first < 0 ? filesize + range.first : range.first return -1, -1 if first < 0 || first >= filesize last = range.last < 0 ? filesize + range.last : range.last last = filesize - 1 if last >= filesize return first, last end end ## # Serves files from a directory class FileHandler < AbstractServlet HandlerTable = Hash.new ## # Allow custom handling of requests for files with +suffix+ by class # +handler+ def self.add_handler(suffix, handler) HandlerTable[suffix] = handler end ## # Remove custom handling of requests for files with +suffix+ def self.remove_handler(suffix) HandlerTable.delete(suffix) end ## # Creates a FileHandler servlet on +server+ that serves files starting # at directory +root+ # # If +options+ is a Hash the following keys are allowed: # # :AcceptableLanguages:: Array of languages allowed for accept-language # :DirectoryCallback:: Allows preprocessing of directory requests # :FancyIndexing:: If true, show an index for directories # :FileCallback:: Allows preprocessing of file requests # :HandlerCallback:: Allows preprocessing of requests # :HandlerTable:: Maps file suffixes to file handlers. # DefaultFileHandler is used by default but any servlet # can be used. # :NondisclosureName:: Do not show files matching this array of globs # :UserDir:: Directory inside ~user to serve content from for /~user # requests. Only works if mounted on / # # If +options+ is true or false then +:FancyIndexing+ is enabled or # disabled respectively. def initialize(server, root, options={}, default=Config::FileHandler) @config = server.config @logger = @config[:Logger] @root = File.expand_path(root) if options == true || options == false options = { :FancyIndexing => options } end @options = default.dup.update(options) end def service(req, res) # if this class is mounted on "/" and /~username is requested. # we're going to override path informations before invoking service. if defined?(Etc) && @options[:UserDir] && req.script_name.empty? if %r|^(/~([^/]+))| =~ req.path_info script_name, user = $1, $2 path_info = $' begin passwd = Etc::getpwnam(user) @root = File::join(passwd.dir, @options[:UserDir]) req.script_name = script_name req.path_info = path_info rescue @logger.debug "#{self.class}#do_GET: getpwnam(#{user}) failed" end end end prevent_directory_traversal(req, res) super(req, res) end def do_GET(req, res) unless exec_handler(req, res) set_dir_list(req, res) end end def do_POST(req, res) unless exec_handler(req, res) raise HTTPStatus::NotFound, "`#{req.path}' not found." end end def do_OPTIONS(req, res) unless exec_handler(req, res) super(req, res) end end # ToDo # RFC2518: HTTP Extensions for Distributed Authoring -- WEBDAV # # PROPFIND PROPPATCH MKCOL DELETE PUT COPY MOVE # LOCK UNLOCK # RFC3253: Versioning Extensions to WebDAV # (Web Distributed Authoring and Versioning) # # VERSION-CONTROL REPORT CHECKOUT CHECK_IN UNCHECKOUT # MKWORKSPACE UPDATE LABEL MERGE ACTIVITY private def trailing_pathsep?(path) # check for trailing path separator: # File.dirname("/aaaa/bbbb/") #=> "/aaaa") # File.dirname("/aaaa/bbbb/x") #=> "/aaaa/bbbb") # File.dirname("/aaaa/bbbb") #=> "/aaaa") # File.dirname("/aaaa/bbbbx") #=> "/aaaa") return File.dirname(path) != File.dirname(path+"x") end def prevent_directory_traversal(req, res) # Preventing directory traversal on Windows platforms; # Backslashes (0x5c) in path_info are not interpreted as special # character in URI notation. So the value of path_info should be # normalize before accessing to the filesystem. # dirty hack for filesystem encoding; in nature, File.expand_path # should not be used for path normalization. [Bug #3345] path = req.path_info.dup.force_encoding(Encoding.find("filesystem")) if trailing_pathsep?(req.path_info) # File.expand_path removes the trailing path separator. # Adding a character is a workaround to save it. # File.expand_path("/aaa/") #=> "/aaa" # File.expand_path("/aaa/" + "x") #=> "/aaa/x" expanded = File.expand_path(path + "x") expanded.chop! # remove trailing "x" else expanded = File.expand_path(path) end expanded.force_encoding(req.path_info.encoding) req.path_info = expanded end def exec_handler(req, res) raise HTTPStatus::NotFound, "`#{req.path}' not found" unless @root if set_filename(req, res) handler = get_handler(req, res) call_callback(:HandlerCallback, req, res) h = handler.get_instance(@config, res.filename) h.service(req, res) return true end call_callback(:HandlerCallback, req, res) return false end def get_handler(req, res) suffix1 = (/\.(\w+)\z/ =~ res.filename) && $1.downcase if /\.(\w+)\.([\w\-]+)\z/ =~ res.filename if @options[:AcceptableLanguages].include?($2.downcase) suffix2 = $1.downcase end end handler_table = @options[:HandlerTable] return handler_table[suffix1] || handler_table[suffix2] || HandlerTable[suffix1] || HandlerTable[suffix2] || DefaultFileHandler end def set_filename(req, res) res.filename = @root.dup path_info = req.path_info.scan(%r|/[^/]*|) path_info.unshift("") # dummy for checking @root dir while base = path_info.first break if base == "/" break unless File.directory?(File.expand_path(res.filename + base)) shift_path_info(req, res, path_info) call_callback(:DirectoryCallback, req, res) end if base = path_info.first if base == "/" if file = search_index_file(req, res) shift_path_info(req, res, path_info, file) call_callback(:FileCallback, req, res) return true end shift_path_info(req, res, path_info) elsif file = search_file(req, res, base) shift_path_info(req, res, path_info, file) call_callback(:FileCallback, req, res) return true else raise HTTPStatus::NotFound, "`#{req.path}' not found." end end return false end def check_filename(req, res, name) if nondisclosure_name?(name) || windows_ambiguous_name?(name) @logger.warn("the request refers nondisclosure name `#{name}'.") raise HTTPStatus::NotFound, "`#{req.path}' not found." end end def shift_path_info(req, res, path_info, base=nil) tmp = path_info.shift base = base || tmp req.path_info = path_info.join req.script_name << base res.filename = File.expand_path(res.filename + base) check_filename(req, res, File.basename(res.filename)) end def search_index_file(req, res) @config[:DirectoryIndex].each{|index| if file = search_file(req, res, "/"+index) return file end } return nil end def search_file(req, res, basename) langs = @options[:AcceptableLanguages] path = res.filename + basename if File.file?(path) return basename elsif langs.size > 0 req.accept_language.each{|lang| path_with_lang = path + ".#{lang}" if langs.member?(lang) && File.file?(path_with_lang) return basename + ".#{lang}" end } (langs - req.accept_language).each{|lang| path_with_lang = path + ".#{lang}" if File.file?(path_with_lang) return basename + ".#{lang}" end } end return nil end def call_callback(callback_name, req, res) if cb = @options[callback_name] cb.call(req, res) end end def windows_ambiguous_name?(name) return true if /[. ]+\z/ =~ name return true if /::\$DATA\z/ =~ name return false end def nondisclosure_name?(name) @options[:NondisclosureName].each{|pattern| if File.fnmatch(pattern, name, File::FNM_CASEFOLD) return true end } return false end def set_dir_list(req, res) redirect_to_directory_uri(req, res) unless @options[:FancyIndexing] raise HTTPStatus::Forbidden, "no access permission to `#{req.path}'" end local_path = res.filename list = Dir::entries(local_path).collect{|name| next if name == "." || name == ".." next if nondisclosure_name?(name) next if windows_ambiguous_name?(name) st = (File::stat(File.join(local_path, name)) rescue nil) if st.nil? [ name, nil, -1 ] elsif st.directory? [ name + "/", st.mtime, -1 ] else [ name, st.mtime, st.size ] end } list.compact! if d0 = req.query["N"]; idx = 0 elsif d0 = req.query["M"]; idx = 1 elsif d0 = req.query["S"]; idx = 2 else d0 = "A" ; idx = 0 end d1 = (d0 == "A") ? "D" : "A" if d0 == "A" list.sort!{|a,b| a[idx] <=> b[idx] } else list.sort!{|a,b| b[idx] <=> a[idx] } end res['content-type'] = "text/html" res.body = <<-_end_of_html_ <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <HTML> <HEAD><TITLE>Index of #{HTMLUtils::escape(req.path)}</TITLE></HEAD> <BODY> <H1>Index of #{HTMLUtils::escape(req.path)}</H1> _end_of_html_ res.body << "<PRE>\n" res.body << " <A HREF=\"?N=#{d1}\">Name</A> " res.body << "<A HREF=\"?M=#{d1}\">Last modified</A> " res.body << "<A HREF=\"?S=#{d1}\">Size</A>\n" res.body << "<HR>\n" list.unshift [ "..", File::mtime(local_path+"/.."), -1 ] list.each{ |name, time, size| if name == ".." dname = "Parent Directory" elsif name.bytesize > 25 dname = name.sub(/^(.{23})(?:.*)/, '\1..') else dname = name end s = " <A HREF=\"#{HTTPUtils::escape(name)}\">#{HTMLUtils::escape(dname)}</A>" s << " " * (30 - dname.bytesize) s << (time ? time.strftime("%Y/%m/%d %H:%M ") : " " * 22) s << (size >= 0 ? size.to_s : "-") << "\n" res.body << s } res.body << "</PRE><HR>" res.body << <<-_end_of_html_ <ADDRESS> #{HTMLUtils::escape(@config[:ServerSoftware])}<BR> at #{req.host}:#{req.port} </ADDRESS> </BODY> </HTML> _end_of_html_ end end end end