# = net/telnet.rb - Simple Telnet Client Library # # Author:: Wakou Aoyama <wakou@ruby-lang.org> # Documentation:: William Webber and Wakou Aoyama # # This file holds the class Net::Telnet, which provides client-side # telnet functionality. # # For documentation, see Net::Telnet. # require "net/protocol" require "English" module Net # # == Net::Telnet # # Provides telnet client functionality. # # This class also has, through delegation, all the methods of a # socket object (by default, a +TCPSocket+, but can be set by the # +Proxy+ option to <tt>new()</tt>). This provides methods such as # <tt>close()</tt> to end the session and <tt>sysread()</tt> to read # data directly from the host, instead of via the <tt>waitfor()</tt> # mechanism. Note that if you do use <tt>sysread()</tt> directly # when in telnet mode, you should probably pass the output through # <tt>preprocess()</tt> to extract telnet command sequences. # # == Overview # # The telnet protocol allows a client to login remotely to a user # account on a server and execute commands via a shell. The equivalent # is done by creating a Net::Telnet class with the +Host+ option # set to your host, calling #login() with your user and password, # issuing one or more #cmd() calls, and then calling #close() # to end the session. The #waitfor(), #print(), #puts(), and # #write() methods, which #cmd() is implemented on top of, are # only needed if you are doing something more complicated. # # A Net::Telnet object can also be used to connect to non-telnet # services, such as SMTP or HTTP. In this case, you normally # want to provide the +Port+ option to specify the port to # connect to, and set the +Telnetmode+ option to false to prevent # the client from attempting to interpret telnet command sequences. # Generally, #login() will not work with other protocols, and you # have to handle authentication yourself. # # For some protocols, it will be possible to specify the +Prompt+ # option once when you create the Telnet object and use #cmd() calls; # for others, you will have to specify the response sequence to # look for as the Match option to every #cmd() call, or call # #puts() and #waitfor() directly; for yet others, you will have # to use #sysread() instead of #waitfor() and parse server # responses yourself. # # It is worth noting that when you create a new Net::Telnet object, # you can supply a proxy IO channel via the Proxy option. This # can be used to attach the Telnet object to other Telnet objects, # to already open sockets, or to any read-write IO object. This # can be useful, for instance, for setting up a test fixture for # unit testing. # # == Examples # # === Log in and send a command, echoing all output to stdout # # localhost = Net::Telnet::new("Host" => "localhost", # "Timeout" => 10, # "Prompt" => /[$%#>] \z/n) # localhost.login("username", "password") { |c| print c } # localhost.cmd("command") { |c| print c } # localhost.close # # # === Check a POP server to see if you have mail # # pop = Net::Telnet::new("Host" => "your_destination_host_here", # "Port" => 110, # "Telnetmode" => false, # "Prompt" => /^\+OK/n) # pop.cmd("user " + "your_username_here") { |c| print c } # pop.cmd("pass " + "your_password_here") { |c| print c } # pop.cmd("list") { |c| print c } # # == References # # There are a large number of RFCs relevant to the Telnet protocol. # RFCs 854-861 define the base protocol. For a complete listing # of relevant RFCs, see # http://www.omnifarious.org/~hopper/technical/telnet-rfc.html # class Telnet # :stopdoc: IAC = 255.chr # "\377" # "\xff" # interpret as command DONT = 254.chr # "\376" # "\xfe" # you are not to use option DO = 253.chr # "\375" # "\xfd" # please, you use option WONT = 252.chr # "\374" # "\xfc" # I won't use option WILL = 251.chr # "\373" # "\xfb" # I will use option SB = 250.chr # "\372" # "\xfa" # interpret as subnegotiation GA = 249.chr # "\371" # "\xf9" # you may reverse the line EL = 248.chr # "\370" # "\xf8" # erase the current line EC = 247.chr # "\367" # "\xf7" # erase the current character AYT = 246.chr # "\366" # "\xf6" # are you there AO = 245.chr # "\365" # "\xf5" # abort output--but let prog finish IP = 244.chr # "\364" # "\xf4" # interrupt process--permanently BREAK = 243.chr # "\363" # "\xf3" # break DM = 242.chr # "\362" # "\xf2" # data mark--for connect. cleaning NOP = 241.chr # "\361" # "\xf1" # nop SE = 240.chr # "\360" # "\xf0" # end sub negotiation EOR = 239.chr # "\357" # "\xef" # end of record (transparent mode) ABORT = 238.chr # "\356" # "\xee" # Abort process SUSP = 237.chr # "\355" # "\xed" # Suspend process EOF = 236.chr # "\354" # "\xec" # End of file SYNCH = 242.chr # "\362" # "\xf2" # for telfunc calls OPT_BINARY = 0.chr # "\000" # "\x00" # Binary Transmission OPT_ECHO = 1.chr # "\001" # "\x01" # Echo OPT_RCP = 2.chr # "\002" # "\x02" # Reconnection OPT_SGA = 3.chr # "\003" # "\x03" # Suppress Go Ahead OPT_NAMS = 4.chr # "\004" # "\x04" # Approx Message Size Negotiation OPT_STATUS = 5.chr # "\005" # "\x05" # Status OPT_TM = 6.chr # "\006" # "\x06" # Timing Mark OPT_RCTE = 7.chr # "\a" # "\x07" # Remote Controlled Trans and Echo OPT_NAOL = 8.chr # "\010" # "\x08" # Output Line Width OPT_NAOP = 9.chr # "\t" # "\x09" # Output Page Size OPT_NAOCRD = 10.chr # "\n" # "\x0a" # Output Carriage-Return Disposition OPT_NAOHTS = 11.chr # "\v" # "\x0b" # Output Horizontal Tab Stops OPT_NAOHTD = 12.chr # "\f" # "\x0c" # Output Horizontal Tab Disposition OPT_NAOFFD = 13.chr # "\r" # "\x0d" # Output Formfeed Disposition OPT_NAOVTS = 14.chr # "\016" # "\x0e" # Output Vertical Tabstops OPT_NAOVTD = 15.chr # "\017" # "\x0f" # Output Vertical Tab Disposition OPT_NAOLFD = 16.chr # "\020" # "\x10" # Output Linefeed Disposition OPT_XASCII = 17.chr # "\021" # "\x11" # Extended ASCII OPT_LOGOUT = 18.chr # "\022" # "\x12" # Logout OPT_BM = 19.chr # "\023" # "\x13" # Byte Macro OPT_DET = 20.chr # "\024" # "\x14" # Data Entry Terminal OPT_SUPDUP = 21.chr # "\025" # "\x15" # SUPDUP OPT_SUPDUPOUTPUT = 22.chr # "\026" # "\x16" # SUPDUP Output OPT_SNDLOC = 23.chr # "\027" # "\x17" # Send Location OPT_TTYPE = 24.chr # "\030" # "\x18" # Terminal Type OPT_EOR = 25.chr # "\031" # "\x19" # End of Record OPT_TUID = 26.chr # "\032" # "\x1a" # TACACS User Identification OPT_OUTMRK = 27.chr # "\e" # "\x1b" # Output Marking OPT_TTYLOC = 28.chr # "\034" # "\x1c" # Terminal Location Number OPT_3270REGIME = 29.chr # "\035" # "\x1d" # Telnet 3270 Regime OPT_X3PAD = 30.chr # "\036" # "\x1e" # X.3 PAD OPT_NAWS = 31.chr # "\037" # "\x1f" # Negotiate About Window Size OPT_TSPEED = 32.chr # " " # "\x20" # Terminal Speed OPT_LFLOW = 33.chr # "!" # "\x21" # Remote Flow Control OPT_LINEMODE = 34.chr # "\"" # "\x22" # Linemode OPT_XDISPLOC = 35.chr # "#" # "\x23" # X Display Location OPT_OLD_ENVIRON = 36.chr # "$" # "\x24" # Environment Option OPT_AUTHENTICATION = 37.chr # "%" # "\x25" # Authentication Option OPT_ENCRYPT = 38.chr # "&" # "\x26" # Encryption Option OPT_NEW_ENVIRON = 39.chr # "'" # "\x27" # New Environment Option OPT_EXOPL = 255.chr # "\377" # "\xff" # Extended-Options-List NULL = "\000" CR = "\015" LF = "\012" EOL = CR + LF REVISION = '$Id$' # :startdoc: # # Creates a new Net::Telnet object. # # Attempts to connect to the host (unless the Proxy option is # provided: see below). If a block is provided, it is yielded # status messages on the attempt to connect to the server, of # the form: # # Trying localhost... # Connected to localhost. # # +options+ is a hash of options. The following example lists # all options and their default values. # # host = Net::Telnet::new( # "Host" => "localhost", # default: "localhost" # "Port" => 23, # default: 23 # "Binmode" => false, # default: false # "Output_log" => "output_log", # default: nil (no output) # "Dump_log" => "dump_log", # default: nil (no output) # "Prompt" => /[$%#>] \z/n, # default: /[$%#>] \z/n # "Telnetmode" => true, # default: true # "Timeout" => 10, # default: 10 # # if ignore timeout then set "Timeout" to false. # "Waittime" => 0, # default: 0 # "Proxy" => proxy # default: nil # # proxy is Net::Telnet or IO object # ) # # The options have the following meanings: # # Host:: the hostname or IP address of the host to connect to, as a String. # Defaults to "localhost". # # Port:: the port to connect to. Defaults to 23. # # Binmode:: if false (the default), newline substitution is performed. # Outgoing LF is # converted to CRLF, and incoming CRLF is converted to LF. If # true, this substitution is not performed. This value can # also be set with the #binmode() method. The # outgoing conversion only applies to the #puts() and #print() # methods, not the #write() method. The precise nature of # the newline conversion is also affected by the telnet options # SGA and BIN. # # Output_log:: the name of the file to write connection status messages # and all received traffic to. In the case of a proper # Telnet session, this will include the client input as # echoed by the host; otherwise, it only includes server # responses. Output is appended verbatim to this file. # By default, no output log is kept. # # Dump_log:: as for Output_log, except that output is written in hexdump # format (16 bytes per line as hex pairs, followed by their # printable equivalent), with connection status messages # preceded by '#', sent traffic preceded by '>', and # received traffic preceded by '<'. By default, not dump log # is kept. # # Prompt:: a regular expression matching the host's command-line prompt # sequence. This is needed by the Telnet class to determine # when the output from a command has finished and the host is # ready to receive a new command. By default, this regular # expression is /[$%#>] \z/n. # # Telnetmode:: a boolean value, true by default. In telnet mode, # traffic received from the host is parsed for special # command sequences, and these sequences are escaped # in outgoing traffic sent using #puts() or #print() # (but not #write()). If you are using the Net::Telnet # object to connect to a non-telnet service (such as # SMTP or POP), this should be set to "false" to prevent # undesired data corruption. This value can also be set # by the #telnetmode() method. # # Timeout:: the number of seconds to wait before timing out both the # initial attempt to connect to host (in this constructor), # which raises a Net::OpenTimeout, and all attempts to read data # from the host, which raises a Net::ReadTimeout (in #waitfor(), # #cmd(), and #login()). The default value is 10 seconds. # You can disable the timeout by setting this value to false. # In this case, the connect attempt will eventually timeout # on the underlying connect(2) socket call with an # Errno::ETIMEDOUT error (but generally only after a few # minutes), but other attempts to read data from the host # will hang indefinitely if no data is forthcoming. # # Waittime:: the amount of time to wait after seeing what looks like a # prompt (that is, received data that matches the Prompt # option regular expression) to see if more data arrives. # If more data does arrive in this time, Net::Telnet assumes # that what it saw was not really a prompt. This is to try to # avoid false matches, but it can also lead to missing real # prompts (if, for instance, a background process writes to # the terminal soon after the prompt is displayed). By # default, set to 0, meaning not to wait for more data. # # Proxy:: a proxy object to used instead of opening a direct connection # to the host. Must be either another Net::Telnet object or # an IO object. If it is another Net::Telnet object, this # instance will use that one's socket for communication. If an # IO object, it is used directly for communication. Any other # kind of object will cause an error to be raised. # def initialize(options) # :yield: mesg @options = options @options["Host"] = "localhost" unless @options.has_key?("Host") @options["Port"] = 23 unless @options.has_key?("Port") @options["Prompt"] = /[$%#>] \z/n unless @options.has_key?("Prompt") @options["Timeout"] = 10 unless @options.has_key?("Timeout") @options["Waittime"] = 0 unless @options.has_key?("Waittime") unless @options.has_key?("Binmode") @options["Binmode"] = false else unless (true == @options["Binmode"] or false == @options["Binmode"]) raise ArgumentError, "Binmode option must be true or false" end end unless @options.has_key?("Telnetmode") @options["Telnetmode"] = true else unless (true == @options["Telnetmode"] or false == @options["Telnetmode"]) raise ArgumentError, "Telnetmode option must be true or false" end end @telnet_option = { "SGA" => false, "BINARY" => false } if @options.has_key?("Output_log") @log = File.open(@options["Output_log"], 'a+') @log.sync = true @log.binmode end if @options.has_key?("Dump_log") @dumplog = File.open(@options["Dump_log"], 'a+') @dumplog.sync = true @dumplog.binmode def @dumplog.log_dump(dir, x) # :nodoc: len = x.length addr = 0 offset = 0 while 0 < len if len < 16 line = x[offset, len] else line = x[offset, 16] end hexvals = line.unpack('H*')[0] hexvals += ' ' * (32 - hexvals.length) hexvals = format("%s %s %s %s " * 4, *hexvals.unpack('a2' * 16)) line = line.gsub(/[\000-\037\177-\377]/n, '.') printf "%s 0x%5.5x: %s%s\n", dir, addr, hexvals, line addr += 16 offset += 16 len -= 16 end print "\n" end end if @options.has_key?("Proxy") if @options["Proxy"].kind_of?(Net::Telnet) @sock = @options["Proxy"].sock elsif @options["Proxy"].kind_of?(IO) @sock = @options["Proxy"] else raise "Error: Proxy must be an instance of Net::Telnet or IO." end else message = "Trying " + @options["Host"] + "...\n" yield(message) if block_given? @log.write(message) if @options.has_key?("Output_log") @dumplog.log_dump('#', message) if @options.has_key?("Dump_log") begin if @options["Timeout"] == false @sock = TCPSocket.open(@options["Host"], @options["Port"]) else Timeout.timeout(@options["Timeout"], Net::OpenTimeout) do @sock = TCPSocket.open(@options["Host"], @options["Port"]) end end rescue Net::OpenTimeout raise Net::OpenTimeout, "timed out while opening a connection to the host" rescue @log.write($ERROR_INFO.to_s + "\n") if @options.has_key?("Output_log") @dumplog.log_dump('#', $ERROR_INFO.to_s + "\n") if @options.has_key?("Dump_log") raise end @sock.sync = true @sock.binmode message = "Connected to " + @options["Host"] + ".\n" yield(message) if block_given? @log.write(message) if @options.has_key?("Output_log") @dumplog.log_dump('#', message) if @options.has_key?("Dump_log") end end # initialize # The socket the Telnet object is using. Note that this object becomes # a delegate of the Telnet object, so normally you invoke its methods # directly on the Telnet object. attr_reader :sock # Set telnet command interpretation on (+mode+ == true) or off # (+mode+ == false), or return the current value (+mode+ not # provided). It should be on for true telnet sessions, off if # using Net::Telnet to connect to a non-telnet service such # as SMTP. def telnetmode(mode = nil) case mode when nil @options["Telnetmode"] when true, false @options["Telnetmode"] = mode else raise ArgumentError, "argument must be true or false, or missing" end end # Turn telnet command interpretation on (true) or off (false). It # should be on for true telnet sessions, off if using Net::Telnet # to connect to a non-telnet service such as SMTP. def telnetmode=(mode) if (true == mode or false == mode) @options["Telnetmode"] = mode else raise ArgumentError, "argument must be true or false" end end # Turn newline conversion on (+mode+ == false) or off (+mode+ == true), # or return the current value (+mode+ is not specified). def binmode(mode = nil) case mode when nil @options["Binmode"] when true, false @options["Binmode"] = mode else raise ArgumentError, "argument must be true or false" end end # Turn newline conversion on (false) or off (true). def binmode=(mode) if (true == mode or false == mode) @options["Binmode"] = mode else raise ArgumentError, "argument must be true or false" end end # Preprocess received data from the host. # # Performs newline conversion and detects telnet command sequences. # Called automatically by #waitfor(). You should only use this # method yourself if you have read input directly using sysread() # or similar, and even then only if in telnet mode. def preprocess(string) # combine CR+NULL into CR string = string.gsub(/#{CR}#{NULL}/no, CR) if @options["Telnetmode"] # combine EOL into "\n" string = string.gsub(/#{EOL}/no, "\n") unless @options["Binmode"] # remove NULL string = string.gsub(/#{NULL}/no, '') unless @options["Binmode"] string.gsub(/#{IAC}( [#{IAC}#{AO}#{AYT}#{DM}#{IP}#{NOP}]| [#{DO}#{DONT}#{WILL}#{WONT}] [#{OPT_BINARY}-#{OPT_NEW_ENVIRON}#{OPT_EXOPL}]| #{SB}[^#{IAC}]*#{IAC}#{SE} )/xno) do if IAC == $1 # handle escaped IAC characters IAC elsif AYT == $1 # respond to "IAC AYT" (are you there) self.write("nobody here but us pigeons" + EOL) '' elsif DO[0] == $1[0] # respond to "IAC DO x" if OPT_BINARY[0] == $1[1] @telnet_option["BINARY"] = true self.write(IAC + WILL + OPT_BINARY) else self.write(IAC + WONT + $1[1..1]) end '' elsif DONT[0] == $1[0] # respond to "IAC DON'T x" with "IAC WON'T x" self.write(IAC + WONT + $1[1..1]) '' elsif WILL[0] == $1[0] # respond to "IAC WILL x" if OPT_BINARY[0] == $1[1] self.write(IAC + DO + OPT_BINARY) elsif OPT_ECHO[0] == $1[1] self.write(IAC + DO + OPT_ECHO) elsif OPT_SGA[0] == $1[1] @telnet_option["SGA"] = true self.write(IAC + DO + OPT_SGA) else self.write(IAC + DONT + $1[1..1]) end '' elsif WONT[0] == $1[0] # respond to "IAC WON'T x" if OPT_ECHO[0] == $1[1] self.write(IAC + DONT + OPT_ECHO) elsif OPT_SGA[0] == $1[1] @telnet_option["SGA"] = false self.write(IAC + DONT + OPT_SGA) else self.write(IAC + DONT + $1[1..1]) end '' else '' end end end # preprocess # Read data from the host until a certain sequence is matched. # # If a block is given, the received data will be yielded as it # is read in (not necessarily all in one go), or nil if EOF # occurs before any data is received. Whether a block is given # or not, all data read will be returned in a single string, or again # nil if EOF occurs before any data is received. Note that # received data includes the matched sequence we were looking for. # # +options+ can be either a regular expression or a hash of options. # If a regular expression, this specifies the data to wait for. # If a hash, this can specify the following options: # # Match:: a regular expression, specifying the data to wait for. # Prompt:: as for Match; used only if Match is not specified. # String:: as for Match, except a string that will be converted # into a regular expression. Used only if Match and # Prompt are not specified. # Timeout:: the number of seconds to wait for data from the host # before raising a Timeout::Error. If set to false, # no timeout will occur. If not specified, the # Timeout option value specified when this instance # was created will be used, or, failing that, the # default value of 10 seconds. # Waittime:: the number of seconds to wait after matching against # the input data to see if more data arrives. If more # data arrives within this time, we will judge ourselves # not to have matched successfully, and will continue # trying to match. If not specified, the Waittime option # value specified when this instance was created will be # used, or, failing that, the default value of 0 seconds, # which means not to wait for more input. # FailEOF:: if true, when the remote end closes the connection then an # EOFError will be raised. Otherwise, defaults to the old # behaviour that the function will return whatever data # has been received already, or nil if nothing was received. # def waitfor(options) # :yield: recvdata time_out = @options["Timeout"] waittime = @options["Waittime"] fail_eof = @options["FailEOF"] if options.kind_of?(Hash) prompt = if options.has_key?("Match") options["Match"] elsif options.has_key?("Prompt") options["Prompt"] elsif options.has_key?("String") Regexp.new( Regexp.quote(options["String"]) ) end time_out = options["Timeout"] if options.has_key?("Timeout") waittime = options["Waittime"] if options.has_key?("Waittime") fail_eof = options["FailEOF"] if options.has_key?("FailEOF") else prompt = options end if time_out == false time_out = nil end line = '' buf = '' rest = '' until(prompt === line and not @sock.wait_readable(waittime)) unless @sock.wait_readable(time_out) raise Net::ReadTimeout, "timed out while waiting for more data" end begin c = @sock.readpartial(1024 * 1024) @dumplog.log_dump('<', c) if @options.has_key?("Dump_log") if @options["Telnetmode"] c = rest + c if Integer(c.rindex(/#{IAC}#{SE}/no) || 0) < Integer(c.rindex(/#{IAC}#{SB}/no) || 0) buf = preprocess(c[0 ... c.rindex(/#{IAC}#{SB}/no)]) rest = c[c.rindex(/#{IAC}#{SB}/no) .. -1] elsif pt = c.rindex(/#{IAC}[^#{IAC}#{AO}#{AYT}#{DM}#{IP}#{NOP}]?\z/no) || c.rindex(/\r\z/no) buf = preprocess(c[0 ... pt]) rest = c[pt .. -1] else buf = preprocess(c) rest = '' end else # Not Telnetmode. # # We cannot use preprocess() on this data, because that # method makes some Telnetmode-specific assumptions. buf = rest + c rest = '' unless @options["Binmode"] if pt = buf.rindex(/\r\z/no) buf = buf[0 ... pt] rest = buf[pt .. -1] end buf.gsub!(/#{EOL}/no, "\n") end end @log.print(buf) if @options.has_key?("Output_log") line += buf yield buf if block_given? rescue EOFError # End of file reached raise if fail_eof if line == '' line = nil yield nil if block_given? end break end end line end # Write +string+ to the host. # # Does not perform any conversions on +string+. Will log +string+ to the # dumplog, if the Dump_log option is set. def write(string) length = string.length while 0 < length @sock.wait_writable @dumplog.log_dump('>', string[-length..-1]) if @options.has_key?("Dump_log") length -= @sock.syswrite(string[-length..-1]) end end # Sends a string to the host. # # This does _not_ automatically append a newline to the string. Embedded # newlines may be converted and telnet command sequences escaped # depending upon the values of telnetmode, binmode, and telnet options # set by the host. def print(string) string = string.gsub(/#{IAC}/no, IAC + IAC) if @options["Telnetmode"] if @options["Binmode"] self.write(string) else if @telnet_option["BINARY"] and @telnet_option["SGA"] # IAC WILL SGA IAC DO BIN send EOL --> CR self.write(string.gsub(/\n/n, CR)) elsif @telnet_option["SGA"] # IAC WILL SGA send EOL --> CR+NULL self.write(string.gsub(/\n/n, CR + NULL)) else # NONE send EOL --> CR+LF self.write(string.gsub(/\n/n, EOL)) end end end # Sends a string to the host. # # Same as #print(), but appends a newline to the string. def puts(string) self.print(string + "\n") end # Send a command to the host. # # More exactly, sends a string to the host, and reads in all received # data until is sees the prompt or other matched sequence. # # If a block is given, the received data will be yielded to it as # it is read in. Whether a block is given or not, the received data # will be return as a string. Note that the received data includes # the prompt and in most cases the host's echo of our command. # # +options+ is either a String, specified the string or command to # send to the host; or it is a hash of options. If a hash, the # following options can be specified: # # String:: the command or other string to send to the host. # Match:: a regular expression, the sequence to look for in # the received data before returning. If not specified, # the Prompt option value specified when this instance # was created will be used, or, failing that, the default # prompt of /[$%#>] \z/n. # Timeout:: the seconds to wait for data from the host before raising # a Timeout error. If not specified, the Timeout option # value specified when this instance was created will be # used, or, failing that, the default value of 10 seconds. # # The command or other string will have the newline sequence appended # to it. def cmd(options) # :yield: recvdata match = @options["Prompt"] time_out = @options["Timeout"] fail_eof = @options["FailEOF"] if options.kind_of?(Hash) string = options["String"] match = options["Match"] if options.has_key?("Match") time_out = options["Timeout"] if options.has_key?("Timeout") fail_eof = options["FailEOF"] if options.has_key?("FailEOF") else string = options end self.puts(string) if block_given? waitfor({"Prompt" => match, "Timeout" => time_out, "FailEOF" => fail_eof}){|c| yield c } else waitfor({"Prompt" => match, "Timeout" => time_out, "FailEOF" => fail_eof}) end end # Login to the host with a given username and password. # # The username and password can either be provided as two string # arguments in that order, or as a hash with keys "Name" and # "Password". # # This method looks for the strings "login" and "Password" from the # host to determine when to send the username and password. If the # login sequence does not follow this pattern (for instance, you # are connecting to a service other than telnet), you will need # to handle login yourself. # # The password can be omitted, either by only # provided one String argument, which will be used as the username, # or by providing a has that has no "Password" key. In this case, # the method will not look for the "Password:" prompt; if it is # sent, it will have to be dealt with by later calls. # # The method returns all data received during the login process from # the host, including the echoed username but not the password (which # the host should not echo). If a block is passed in, this received # data is also yielded to the block as it is received. def login(options, password = nil) # :yield: recvdata login_prompt = /[Ll]ogin[: ]*\z/n password_prompt = /[Pp]ass(?:word|phrase)[: ]*\z/n if options.kind_of?(Hash) username = options["Name"] password = options["Password"] login_prompt = options["LoginPrompt"] if options["LoginPrompt"] password_prompt = options["PasswordPrompt"] if options["PasswordPrompt"] else username = options end if block_given? line = waitfor(login_prompt){|c| yield c } if password line += cmd({"String" => username, "Match" => password_prompt}){|c| yield c } line += cmd(password){|c| yield c } else line += cmd(username){|c| yield c } end else line = waitfor(login_prompt) if password line += cmd({"String" => username, "Match" => password_prompt}) line += cmd(password) else line += cmd(username) end end line end # Closes the connection def close @sock.close end end # class Telnet end # module Net