# Net::Cmd.pm # # Versions up to 2.29_1 Copyright (c) 1995-2006 Graham Barr . # All rights reserved. # Changes in Version 2.29_2 onwards Copyright (C) 2013-2014 Steve Hay. All # rights reserved. # This program is free software; you can redistribute it and/or # modify it under the same terms as Perl itself. package Net::Cmd; use 5.008001; use strict; use warnings; use Carp; use Exporter; use Symbol 'gensym'; BEGIN { if ($^O eq 'os390') { require Convert::EBCDIC; # Convert::EBCDIC->import; } } BEGIN { if (!eval { require utf8 }) { *is_utf8 = sub { 0 }; } elsif (eval { utf8::is_utf8(undef); 1 }) { *is_utf8 = \&utf8::is_utf8; } elsif (eval { require Encode; Encode::is_utf8(undef); 1 }) { *is_utf8 = \&Encode::is_utf8; } else { *is_utf8 = sub { $_[0] =~ /[^\x00-\xff]/ }; } } our $VERSION = "3.05"; our @ISA = qw(Exporter); our @EXPORT = qw(CMD_INFO CMD_OK CMD_MORE CMD_REJECT CMD_ERROR CMD_PENDING); use constant CMD_INFO => 1; use constant CMD_OK => 2; use constant CMD_MORE => 3; use constant CMD_REJECT => 4; use constant CMD_ERROR => 5; use constant CMD_PENDING => 0; use constant DEF_REPLY_CODE => 421; my %debug = (); my $tr = $^O eq 'os390' ? Convert::EBCDIC->new() : undef; sub toebcdic { my $cmd = shift; unless (exists ${*$cmd}{'net_cmd_asciipeer'}) { my $string = $_[0]; my $ebcdicstr = $tr->toebcdic($string); ${*$cmd}{'net_cmd_asciipeer'} = $string !~ /^\d+/ && $ebcdicstr =~ /^\d+/; } ${*$cmd}{'net_cmd_asciipeer'} ? $tr->toebcdic($_[0]) : $_[0]; } sub toascii { my $cmd = shift; ${*$cmd}{'net_cmd_asciipeer'} ? $tr->toascii($_[0]) : $_[0]; } sub _print_isa { no strict 'refs'; ## no critic (TestingAndDebugging::ProhibitNoStrict) my $pkg = shift; my $cmd = $pkg; $debug{$pkg} ||= 0; my %done = (); my @do = ($pkg); my %spc = ($pkg, ""); while ($pkg = shift @do) { next if defined $done{$pkg}; $done{$pkg} = 1; my $v = defined ${"${pkg}::VERSION"} ? "(" . ${"${pkg}::VERSION"} . ")" : ""; my $spc = $spc{$pkg}; $cmd->debug_print(1, "${spc}${pkg}${v}\n"); if (@{"${pkg}::ISA"}) { @spc{@{"${pkg}::ISA"}} = (" " . $spc{$pkg}) x @{"${pkg}::ISA"}; unshift(@do, @{"${pkg}::ISA"}); } } } sub debug { @_ == 1 or @_ == 2 or croak 'usage: $obj->debug([LEVEL])'; my ($cmd, $level) = @_; my $pkg = ref($cmd) || $cmd; my $oldval = 0; if (ref($cmd)) { $oldval = ${*$cmd}{'net_cmd_debug'} || 0; } else { $oldval = $debug{$pkg} || 0; } return $oldval unless @_ == 2; $level = $debug{$pkg} || 0 unless defined $level; _print_isa($pkg) if ($level && !exists $debug{$pkg}); if (ref($cmd)) { ${*$cmd}{'net_cmd_debug'} = $level; } else { $debug{$pkg} = $level; } $oldval; } sub message { @_ == 1 or croak 'usage: $obj->message()'; my $cmd = shift; wantarray ? @{${*$cmd}{'net_cmd_resp'}} : join("", @{${*$cmd}{'net_cmd_resp'}}); } sub debug_text { $_[2] } sub debug_print { my ($cmd, $out, $text) = @_; print STDERR $cmd, ($out ? '>>> ' : '<<< '), $cmd->debug_text($out, $text); } sub code { @_ == 1 or croak 'usage: $obj->code()'; my $cmd = shift; ${*$cmd}{'net_cmd_code'} = $cmd->DEF_REPLY_CODE unless exists ${*$cmd}{'net_cmd_code'}; ${*$cmd}{'net_cmd_code'}; } sub status { @_ == 1 or croak 'usage: $obj->status()'; my $cmd = shift; substr(${*$cmd}{'net_cmd_code'}, 0, 1); } sub set_status { @_ == 3 or croak 'usage: $obj->set_status(CODE, MESSAGE)'; my $cmd = shift; my ($code, $resp) = @_; $resp = defined $resp ? [$resp] : [] unless ref($resp); (${*$cmd}{'net_cmd_code'}, ${*$cmd}{'net_cmd_resp'}) = ($code, $resp); 1; } sub _set_status_timeout { my $cmd = shift; my $pkg = ref($cmd) || $cmd; $cmd->set_status($cmd->DEF_REPLY_CODE, "[$pkg] Timeout"); carp(ref($cmd) . ": " . (caller(1))[3] . "(): timeout") if $cmd->debug; } sub _set_status_closed { my $cmd = shift; my $pkg = ref($cmd) || $cmd; $cmd->set_status($cmd->DEF_REPLY_CODE, "[$pkg] Connection closed"); carp(ref($cmd) . ": " . (caller(1))[3] . "(): unexpected EOF on command channel: $!") if $cmd->debug; } sub _is_closed { my $cmd = shift; if (!defined fileno($cmd)) { $cmd->_set_status_closed; return 1; } return 0; } sub command { my $cmd = shift; return $cmd if $cmd->_is_closed; $cmd->dataend() if (exists ${*$cmd}{'net_cmd_last_ch'}); if (scalar(@_)) { local $SIG{PIPE} = 'IGNORE' unless $^O eq 'MacOS'; my $str = join( " ", map { /\n/ ? do { my $n = $_; $n =~ tr/\n/ /; $n } : $_; } @_ ); $str = $cmd->toascii($str) if $tr; $str .= "\015\012"; my $len = length $str; my $swlen; $cmd->debug_print(1, $str) if ($cmd->debug); unless (defined($swlen = syswrite($cmd,$str,$len)) && $swlen == $len) { $cmd->close; $cmd->_set_status_closed; return $cmd; } } $cmd; } sub ok { @_ == 1 or croak 'usage: $obj->ok()'; my $code = $_[0]->code; 0 < $code && $code < 400; } sub unsupported { my $cmd = shift; $cmd->set_status(580, 'Unsupported command'); 0; } sub getline { my $cmd = shift; ${*$cmd}{'net_cmd_lines'} ||= []; return shift @{${*$cmd}{'net_cmd_lines'}} if scalar(@{${*$cmd}{'net_cmd_lines'}}); my $partial = defined(${*$cmd}{'net_cmd_partial'}) ? ${*$cmd}{'net_cmd_partial'} : ""; return if $cmd->_is_closed; my $fd = fileno($cmd); my $rin = ""; vec($rin, $fd, 1) = 1; my $buf; until (scalar(@{${*$cmd}{'net_cmd_lines'}})) { my $timeout = $cmd->timeout || undef; my $rout; my $select_ret = select($rout = $rin, undef, undef, $timeout); if ($select_ret > 0) { unless (sysread($cmd, $buf = "", 1024)) { $cmd->close; $cmd->_set_status_closed; return; } substr($buf, 0, 0) = $partial; ## prepend from last sysread my @buf = split(/\015?\012/, $buf, -1); ## break into lines $partial = pop @buf; push(@{${*$cmd}{'net_cmd_lines'}}, map {"$_\n"} @buf); } else { $cmd->_set_status_timeout; return; } } ${*$cmd}{'net_cmd_partial'} = $partial; if ($tr) { foreach my $ln (@{${*$cmd}{'net_cmd_lines'}}) { $ln = $cmd->toebcdic($ln); } } shift @{${*$cmd}{'net_cmd_lines'}}; } sub ungetline { my ($cmd, $str) = @_; ${*$cmd}{'net_cmd_lines'} ||= []; unshift(@{${*$cmd}{'net_cmd_lines'}}, $str); } sub parse_response { return () unless $_[1] =~ s/^(\d\d\d)(.?)//o; ($1, $2 eq "-"); } sub response { my $cmd = shift; my ($code, $more) = (undef) x 2; $cmd->set_status($cmd->DEF_REPLY_CODE, undef); # initialize the response while (1) { my $str = $cmd->getline(); return CMD_ERROR unless defined($str); $cmd->debug_print(0, $str) if ($cmd->debug); ($code, $more) = $cmd->parse_response($str); unless (defined $code) { carp("$cmd: response(): parse error in '$str'") if ($cmd->debug); $cmd->ungetline($str); $@ = $str; # $@ used as tunneling hack return CMD_ERROR; } ${*$cmd}{'net_cmd_code'} = $code; push(@{${*$cmd}{'net_cmd_resp'}}, $str); last unless ($more); } return unless defined $code; substr($code, 0, 1); } sub read_until_dot { my $cmd = shift; my $fh = shift; my $arr = []; while (1) { my $str = $cmd->getline() or return; $cmd->debug_print(0, $str) if ($cmd->debug & 4); last if ($str =~ /^\.\r?\n/o); $str =~ s/^\.\././o; if (defined $fh) { print $fh $str; } else { push(@$arr, $str); } } $arr; } sub datasend { my $cmd = shift; my $arr = @_ == 1 && ref($_[0]) ? $_[0] : \@_; my $line = join("", @$arr); # encode to individual utf8 bytes if # $line is a string (in internal UTF-8) utf8::encode($line) if is_utf8($line); return 0 if $cmd->_is_closed; my $last_ch = ${*$cmd}{'net_cmd_last_ch'}; # We have not send anything yet, so last_ch = "\012" means we are at the start of a line $last_ch = ${*$cmd}{'net_cmd_last_ch'} = "\012" unless defined $last_ch; return 1 unless length $line; if ($cmd->debug) { foreach my $b (split(/\n/, $line)) { $cmd->debug_print(1, "$b\n"); } } $line =~ tr/\r\n/\015\012/ unless "\r" eq "\015"; my $first_ch = ''; if ($last_ch eq "\015") { # Remove \012 so it does not get prefixed with another \015 below # and escape the . if there is one following it because the fixup # below will not find it $first_ch = "\012" if $line =~ s/^\012(\.?)/$1$1/; } elsif ($last_ch eq "\012") { # Fixup below will not find the . as the first character of the buffer $first_ch = "." if $line =~ /^\./; } $line =~ s/\015?\012(\.?)/\015\012$1$1/sg; substr($line, 0, 0) = $first_ch; ${*$cmd}{'net_cmd_last_ch'} = substr($line, -1, 1); my $len = length($line); my $offset = 0; my $win = ""; vec($win, fileno($cmd), 1) = 1; my $timeout = $cmd->timeout || undef; local $SIG{PIPE} = 'IGNORE' unless $^O eq 'MacOS'; while ($len) { my $wout; my $s = select(undef, $wout = $win, undef, $timeout); if ((defined $s and $s > 0) or -f $cmd) # -f for testing on win32 { my $w = syswrite($cmd, $line, $len, $offset); unless (defined($w) && $w == $len) { $cmd->close; $cmd->_set_status_closed; return; } $len -= $w; $offset += $w; } else { $cmd->_set_status_timeout; return; } } 1; } sub rawdatasend { my $cmd = shift; my $arr = @_ == 1 && ref($_[0]) ? $_[0] : \@_; my $line = join("", @$arr); return 0 if $cmd->_is_closed; return 1 unless length($line); if ($cmd->debug) { my $b = "$cmd>>> "; print STDERR $b, join("\n$b", split(/\n/, $line)), "\n"; } my $len = length($line); my $offset = 0; my $win = ""; vec($win, fileno($cmd), 1) = 1; my $timeout = $cmd->timeout || undef; local $SIG{PIPE} = 'IGNORE' unless $^O eq 'MacOS'; while ($len) { my $wout; if (select(undef, $wout = $win, undef, $timeout) > 0) { my $w = syswrite($cmd, $line, $len, $offset); unless (defined($w) && $w == $len) { $cmd->close; $cmd->_set_status_closed; return; } $len -= $w; $offset += $w; } else { $cmd->_set_status_timeout; return; } } 1; } sub dataend { my $cmd = shift; return 0 if $cmd->_is_closed; my $ch = ${*$cmd}{'net_cmd_last_ch'}; my $tosend; if (!defined $ch) { return 1; } elsif ($ch ne "\012") { $tosend = "\015\012"; } $tosend .= ".\015\012"; local $SIG{PIPE} = 'IGNORE' unless $^O eq 'MacOS'; $cmd->debug_print(1, ".\n") if ($cmd->debug); my $len = length $tosend; my $w = syswrite($cmd, $tosend, $len); unless (defined($w) && $w == $len) { $cmd->close; $cmd->_set_status_closed; return 0; } delete ${*$cmd}{'net_cmd_last_ch'}; $cmd->response() == CMD_OK; } # read and write to tied filehandle sub tied_fh { my $cmd = shift; ${*$cmd}{'net_cmd_readbuf'} = ''; my $fh = gensym(); tie *$fh, ref($cmd), $cmd; return $fh; } # tie to myself sub TIEHANDLE { my $class = shift; my $cmd = shift; return $cmd; } # Tied filehandle read. Reads requested data length, returning # end-of-file when the dot is encountered. sub READ { my $cmd = shift; my ($len, $offset) = @_[1, 2]; return unless exists ${*$cmd}{'net_cmd_readbuf'}; my $done = 0; while (!$done and length(${*$cmd}{'net_cmd_readbuf'}) < $len) { ${*$cmd}{'net_cmd_readbuf'} .= $cmd->getline() or return; $done++ if ${*$cmd}{'net_cmd_readbuf'} =~ s/^\.\r?\n\Z//m; } $_[0] = ''; substr($_[0], $offset + 0) = substr(${*$cmd}{'net_cmd_readbuf'}, 0, $len); substr(${*$cmd}{'net_cmd_readbuf'}, 0, $len) = ''; delete ${*$cmd}{'net_cmd_readbuf'} if $done; return length $_[0]; } sub READLINE { my $cmd = shift; # in this context, we use the presence of readbuf to # indicate that we have not yet reached the eof return unless exists ${*$cmd}{'net_cmd_readbuf'}; my $line = $cmd->getline; return if $line =~ /^\.\r?\n/; $line; } sub PRINT { my $cmd = shift; my ($buf, $len, $offset) = @_; $len ||= length($buf); $offset += 0; return unless $cmd->datasend(substr($buf, $offset, $len)); ${*$cmd}{'net_cmd_sending'}++; # flag that we should call dataend() return $len; } sub CLOSE { my $cmd = shift; my $r = exists(${*$cmd}{'net_cmd_sending'}) ? $cmd->dataend : 1; delete ${*$cmd}{'net_cmd_readbuf'}; delete ${*$cmd}{'net_cmd_sending'}; $r; } 1; __END__ =head1 NAME Net::Cmd - Network Command class (as used by FTP, SMTP etc) =head1 SYNOPSIS use Net::Cmd; @ISA = qw(Net::Cmd); =head1 DESCRIPTION C is a collection of methods that can be inherited by a sub class of C. These methods implement the functionality required for a command based protocol, for example FTP and SMTP. =head1 USER METHODS These methods provide a user interface to the C object. =over 4 =item debug ( VALUE ) Set the level of debug information for this object. If C is not given then the current state is returned. Otherwise the state is changed to C and the previous state returned. Different packages may implement different levels of debug but a non-zero value results in copies of all commands and responses also being sent to STDERR. If C is C then the debug level will be set to the default debug level for the class. This method can also be called as a I method to set/get the default debug level for a given class. =item message () Returns the text message returned from the last command. In a scalar context it returns a single string, in a list context it will return each line as a separate element. (See L below.) =item code () Returns the 3-digit code from the last command. If a command is pending then the value 0 is returned. (See L below.) =item ok () Returns non-zero if the last code value was greater than zero and less than 400. This holds true for most command servers. Servers where this does not hold may override this method. =item status () Returns the most significant digit of the current status code. If a command is pending then C is returned. =item datasend ( DATA ) Send data to the remote server, converting LF to CRLF. Any line starting with a '.' will be prefixed with another '.'. C may be an array or a reference to an array. =item dataend () End the sending of data to the remote server. This is done by ensuring that the data already sent ends with CRLF then sending '.CRLF' to end the transmission. Once this data has been sent C calls C and returns true if C returns CMD_OK. =back =head1 CLASS METHODS These methods are not intended to be called by the user, but used or over-ridden by a sub-class of C =over 4 =item debug_print ( DIR, TEXT ) Print debugging information. C denotes the direction I being data being sent to the server. Calls C before printing to STDERR. =item debug_text ( DIR, TEXT ) This method is called to print debugging information. TEXT is the text being sent. The method should return the text to be printed. This is primarily meant for the use of modules such as FTP where passwords are sent, but we do not want to display them in the debugging information. =item command ( CMD [, ARGS, ... ]) Send a command to the command server. All arguments are first joined with a space character and CRLF is appended, this string is then sent to the command server. Returns undef upon failure. =item unsupported () Sets the status code to 580 and the response text to 'Unsupported command'. Returns zero. =item response () Obtain a response from the server. Upon success the most significant digit of the status code is returned. Upon failure, timeout etc., I is returned. =item parse_response ( TEXT ) This method is called by C as a method with one argument. It should return an array of 2 values, the 3-digit status code and a flag which is true when this is part of a multi-line response and this line is not the last. =item getline () Retrieve one line, delimited by CRLF, from the remote server. Returns I upon failure. B: If you do use this method for any reason, please remember to add some C calls into your method. =item ungetline ( TEXT ) Unget a line of text from the server. =item rawdatasend ( DATA ) Send data to the remote server without performing any conversions. C is a scalar. =item read_until_dot () Read data from the remote server until a line consisting of a single '.'. Any lines starting with '..' will have one of the '.'s removed. Returns a reference to a list containing the lines, or I upon failure. =item tied_fh () Returns a filehandle tied to the Net::Cmd object. After issuing a command, you may read from this filehandle using read() or <>. The filehandle will return EOF when the final dot is encountered. Similarly, you may write to the filehandle in order to send data to the server after issuing a command that expects data to be written. See the Net::POP3 and Net::SMTP modules for examples of this. =back =head1 PSEUDO RESPONSES Normally the values returned by C and C are obtained from the remote server, but in a few circumstances, as detailed below, C will return values that it sets. You can alter this behavior by overriding DEF_REPLY_CODE() to specify a different default reply code, or overriding one of the specific error handling methods below. =over 4 =item Initial value Before any command has executed or if an unexpected error occurs C will return "421" (temporary connection failure) and C will return undef. =item Connection closed If the underlying C is closed, or if there are any read or write failures, the file handle will be forced closed, and C will return "421" (temporary connection failure) and C will return "[$pkg] Connection closed" (where $pkg is the name of the class that subclassed C). The _set_status_closed() method can be overridden to set a different message (by calling set_status()) or otherwise trap this error. =item Timeout If there is a read or write timeout C will return "421" (temporary connection failure) and C will return "[$pkg] Timeout" (where $pkg is the name of the class that subclassed C). The _set_status_timeout() method can be overridden to set a different message (by calling set_status()) or otherwise trap this error. =back =head1 EXPORTS C exports six subroutines, five of these, C, C, C, C and C, correspond to possible results of C and C. The sixth is C. =head1 AUTHOR Graham Barr EFE Steve Hay EFE is now maintaining libnet as of version 1.22_02 =head1 COPYRIGHT Versions up to 2.29_1 Copyright (c) 1995-2006 Graham Barr. All rights reserved. Changes in Version 2.29_2 onwards Copyright (C) 2013-2014 Steve Hay. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut