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Diffstat (limited to 'contrib/perl5/lib/Net/Ping.pm')
| -rw-r--r-- | contrib/perl5/lib/Net/Ping.pm | 559 |
1 files changed, 0 insertions, 559 deletions
diff --git a/contrib/perl5/lib/Net/Ping.pm b/contrib/perl5/lib/Net/Ping.pm deleted file mode 100644 index a2846fe..0000000 --- a/contrib/perl5/lib/Net/Ping.pm +++ /dev/null @@ -1,559 +0,0 @@ -package Net::Ping; - -# Author: mose@ccsn.edu (Russell Mosemann) -# -# Authors of the original pingecho(): -# karrer@bernina.ethz.ch (Andreas Karrer) -# Paul.Marquess@btinternet.com (Paul Marquess) -# -# Copyright (c) 1996 Russell Mosemann. All rights reserved. This -# program is free software; you may redistribute it and/or modify it -# under the same terms as Perl itself. - -use 5.005_64; -require Exporter; - -use strict; -our(@ISA, @EXPORT, $VERSION, $def_timeout, $def_proto, $max_datasize); -use FileHandle; -use Socket qw( SOCK_DGRAM SOCK_STREAM SOCK_RAW PF_INET - inet_aton sockaddr_in ); -use Carp; - -@ISA = qw(Exporter); -@EXPORT = qw(pingecho); -$VERSION = 2.02; - -# Constants - -$def_timeout = 5; # Default timeout to wait for a reply -$def_proto = "udp"; # Default protocol to use for pinging -$max_datasize = 1024; # Maximum data bytes in a packet - -# Description: The pingecho() subroutine is provided for backward -# compatibility with the original Net::Ping. It accepts a host -# name/IP and an optional timeout in seconds. Create a tcp ping -# object and try pinging the host. The result of the ping is returned. - -sub pingecho -{ - my ($host, # Name or IP number of host to ping - $timeout # Optional timeout in seconds - ) = @_; - my ($p); # A ping object - - $p = Net::Ping->new("tcp", $timeout); - $p->ping($host); # Going out of scope closes the connection -} - -# Description: The new() method creates a new ping object. Optional -# parameters may be specified for the protocol to use, the timeout in -# seconds and the size in bytes of additional data which should be -# included in the packet. -# After the optional parameters are checked, the data is constructed -# and a socket is opened if appropriate. The object is returned. - -sub new -{ - my ($this, - $proto, # Optional protocol to use for pinging - $timeout, # Optional timeout in seconds - $data_size # Optional additional bytes of data - ) = @_; - my $class = ref($this) || $this; - my $self = {}; - my ($cnt, # Count through data bytes - $min_datasize # Minimum data bytes required - ); - - bless($self, $class); - - $proto = $def_proto unless $proto; # Determine the protocol - croak("Protocol for ping must be \"tcp\", \"udp\" or \"icmp\"") - unless $proto =~ m/^(tcp|udp|icmp)$/; - $self->{"proto"} = $proto; - - $timeout = $def_timeout unless $timeout; # Determine the timeout - croak("Default timeout for ping must be greater than 0 seconds") - if $timeout <= 0; - $self->{"timeout"} = $timeout; - - $min_datasize = ($proto eq "udp") ? 1 : 0; # Determine data size - $data_size = $min_datasize unless defined($data_size) && $proto ne "tcp"; - croak("Data for ping must be from $min_datasize to $max_datasize bytes") - if ($data_size < $min_datasize) || ($data_size > $max_datasize); - $data_size-- if $self->{"proto"} eq "udp"; # We provide the first byte - $self->{"data_size"} = $data_size; - - $self->{"data"} = ""; # Construct data bytes - for ($cnt = 0; $cnt < $self->{"data_size"}; $cnt++) - { - $self->{"data"} .= chr($cnt % 256); - } - - $self->{"seq"} = 0; # For counting packets - if ($self->{"proto"} eq "udp") # Open a socket - { - $self->{"proto_num"} = (getprotobyname('udp'))[2] || - croak("Can't udp protocol by name"); - $self->{"port_num"} = (getservbyname('echo', 'udp'))[2] || - croak("Can't get udp echo port by name"); - $self->{"fh"} = FileHandle->new(); - socket($self->{"fh"}, &PF_INET(), &SOCK_DGRAM(), - $self->{"proto_num"}) || - croak("udp socket error - $!"); - } - elsif ($self->{"proto"} eq "icmp") - { - croak("icmp ping requires root privilege") if ($> and $^O ne 'VMS'); - $self->{"proto_num"} = (getprotobyname('icmp'))[2] || - croak("Can't get icmp protocol by name"); - $self->{"pid"} = $$ & 0xffff; # Save lower 16 bits of pid - $self->{"fh"} = FileHandle->new(); - socket($self->{"fh"}, &PF_INET(), &SOCK_RAW(), $self->{"proto_num"}) || - croak("icmp socket error - $!"); - } - elsif ($self->{"proto"} eq "tcp") # Just a file handle for now - { - $self->{"proto_num"} = (getprotobyname('tcp'))[2] || - croak("Can't get tcp protocol by name"); - $self->{"port_num"} = (getservbyname('echo', 'tcp'))[2] || - croak("Can't get tcp echo port by name"); - $self->{"fh"} = FileHandle->new(); - } - - - return($self); -} - -# Description: Ping a host name or IP number with an optional timeout. -# First lookup the host, and return undef if it is not found. Otherwise -# perform the specific ping method based on the protocol. Return the -# result of the ping. - -sub ping -{ - my ($self, - $host, # Name or IP number of host to ping - $timeout # Seconds after which ping times out - ) = @_; - my ($ip, # Packed IP number of $host - $ret # The return value - ); - - croak("Usage: \$p->ping(\$host [, \$timeout])") unless @_ == 2 || @_ == 3; - $timeout = $self->{"timeout"} unless $timeout; - croak("Timeout must be greater than 0 seconds") if $timeout <= 0; - - $ip = inet_aton($host); - return(undef) unless defined($ip); # Does host exist? - - if ($self->{"proto"} eq "udp") - { - $ret = $self->ping_udp($ip, $timeout); - } - elsif ($self->{"proto"} eq "icmp") - { - $ret = $self->ping_icmp($ip, $timeout); - } - elsif ($self->{"proto"} eq "tcp") - { - $ret = $self->ping_tcp($ip, $timeout); - } - else - { - croak("Unknown protocol \"$self->{proto}\" in ping()"); - } - return($ret); -} - -sub ping_icmp -{ - my ($self, - $ip, # Packed IP number of the host - $timeout # Seconds after which ping times out - ) = @_; - - my $ICMP_ECHOREPLY = 0; # ICMP packet types - my $ICMP_ECHO = 8; - my $icmp_struct = "C2 S3 A"; # Structure of a minimal ICMP packet - my $subcode = 0; # No ICMP subcode for ECHO and ECHOREPLY - my $flags = 0; # No special flags when opening a socket - my $port = 0; # No port with ICMP - - my ($saddr, # sockaddr_in with port and ip - $checksum, # Checksum of ICMP packet - $msg, # ICMP packet to send - $len_msg, # Length of $msg - $rbits, # Read bits, filehandles for reading - $nfound, # Number of ready filehandles found - $finish_time, # Time ping should be finished - $done, # set to 1 when we are done - $ret, # Return value - $recv_msg, # Received message including IP header - $from_saddr, # sockaddr_in of sender - $from_port, # Port packet was sent from - $from_ip, # Packed IP of sender - $from_type, # ICMP type - $from_subcode, # ICMP subcode - $from_chk, # ICMP packet checksum - $from_pid, # ICMP packet id - $from_seq, # ICMP packet sequence - $from_msg # ICMP message - ); - - $self->{"seq"} = ($self->{"seq"} + 1) % 65536; # Increment sequence - $checksum = 0; # No checksum for starters - $msg = pack($icmp_struct . $self->{"data_size"}, $ICMP_ECHO, $subcode, - $checksum, $self->{"pid"}, $self->{"seq"}, $self->{"data"}); - $checksum = Net::Ping->checksum($msg); - $msg = pack($icmp_struct . $self->{"data_size"}, $ICMP_ECHO, $subcode, - $checksum, $self->{"pid"}, $self->{"seq"}, $self->{"data"}); - $len_msg = length($msg); - $saddr = sockaddr_in($port, $ip); - send($self->{"fh"}, $msg, $flags, $saddr); # Send the message - - $rbits = ""; - vec($rbits, $self->{"fh"}->fileno(), 1) = 1; - $ret = 0; - $done = 0; - $finish_time = time() + $timeout; # Must be done by this time - while (!$done && $timeout > 0) # Keep trying if we have time - { - $nfound = select($rbits, undef, undef, $timeout); # Wait for packet - $timeout = $finish_time - time(); # Get remaining time - if (!defined($nfound)) # Hmm, a strange error - { - $ret = undef; - $done = 1; - } - elsif ($nfound) # Got a packet from somewhere - { - $recv_msg = ""; - $from_saddr = recv($self->{"fh"}, $recv_msg, 1500, $flags); - ($from_port, $from_ip) = sockaddr_in($from_saddr); - ($from_type, $from_subcode, $from_chk, - $from_pid, $from_seq, $from_msg) = - unpack($icmp_struct . $self->{"data_size"}, - substr($recv_msg, length($recv_msg) - $len_msg, - $len_msg)); - if (($from_type == $ICMP_ECHOREPLY) && - ($from_ip eq $ip) && - ($from_pid == $self->{"pid"}) && # Does the packet check out? - ($from_seq == $self->{"seq"})) - { - $ret = 1; # It's a winner - $done = 1; - } - } - else # Oops, timed out - { - $done = 1; - } - } - return($ret) -} - -# Description: Do a checksum on the message. Basically sum all of -# the short words and fold the high order bits into the low order bits. - -sub checksum -{ - my ($class, - $msg # The message to checksum - ) = @_; - my ($len_msg, # Length of the message - $num_short, # The number of short words in the message - $short, # One short word - $chk # The checksum - ); - - $len_msg = length($msg); - $num_short = int($len_msg / 2); - $chk = 0; - foreach $short (unpack("S$num_short", $msg)) - { - $chk += $short; - } # Add the odd byte in - $chk += (unpack("C", substr($msg, $len_msg - 1, 1)) << 8) if $len_msg % 2; - $chk = ($chk >> 16) + ($chk & 0xffff); # Fold high into low - return(~(($chk >> 16) + $chk) & 0xffff); # Again and complement -} - -# Description: Perform a tcp echo ping. Since a tcp connection is -# host specific, we have to open and close each connection here. We -# can't just leave a socket open. Because of the robust nature of -# tcp, it will take a while before it gives up trying to establish a -# connection. Therefore, we have to set the alarm to break out of the -# connection sooner if the timeout expires. No data bytes are actually -# sent since the successful establishment of a connection is proof -# enough of the reachability of the remote host. Also, tcp is -# expensive and doesn't need our help to add to the overhead. - -sub ping_tcp -{ - my ($self, - $ip, # Packed IP number of the host - $timeout # Seconds after which ping times out - ) = @_; - my ($saddr, # sockaddr_in with port and ip - $ret # The return value - ); - - socket($self->{"fh"}, &PF_INET(), &SOCK_STREAM(), $self->{"proto_num"}) || - croak("tcp socket error - $!"); - $saddr = sockaddr_in($self->{"port_num"}, $ip); - - $SIG{'ALRM'} = sub { die }; - alarm($timeout); # Interrupt connect() if we have to - - $ret = 0; # Default to unreachable - eval <<'EOM' ; - return unless connect($self->{"fh"}, $saddr); - $ret = 1; -EOM - alarm(0); - $self->{"fh"}->close(); - return($ret); -} - -# Description: Perform a udp echo ping. Construct a message of -# at least the one-byte sequence number and any additional data bytes. -# Send the message out and wait for a message to come back. If we -# get a message, make sure all of its parts match. If they do, we are -# done. Otherwise go back and wait for the message until we run out -# of time. Return the result of our efforts. - -sub ping_udp -{ - my ($self, - $ip, # Packed IP number of the host - $timeout # Seconds after which ping times out - ) = @_; - - my $flags = 0; # Nothing special on open - - my ($saddr, # sockaddr_in with port and ip - $ret, # The return value - $msg, # Message to be echoed - $finish_time, # Time ping should be finished - $done, # Set to 1 when we are done pinging - $rbits, # Read bits, filehandles for reading - $nfound, # Number of ready filehandles found - $from_saddr, # sockaddr_in of sender - $from_msg, # Characters echoed by $host - $from_port, # Port message was echoed from - $from_ip # Packed IP number of sender - ); - - $saddr = sockaddr_in($self->{"port_num"}, $ip); - $self->{"seq"} = ($self->{"seq"} + 1) % 256; # Increment sequence - $msg = chr($self->{"seq"}) . $self->{"data"}; # Add data if any - send($self->{"fh"}, $msg, $flags, $saddr); # Send it - - $rbits = ""; - vec($rbits, $self->{"fh"}->fileno(), 1) = 1; - $ret = 0; # Default to unreachable - $done = 0; - $finish_time = time() + $timeout; # Ping needs to be done by then - while (!$done && $timeout > 0) - { - $nfound = select($rbits, undef, undef, $timeout); # Wait for response - $timeout = $finish_time - time(); # Get remaining time - - if (!defined($nfound)) # Hmm, a strange error - { - $ret = undef; - $done = 1; - } - elsif ($nfound) # A packet is waiting - { - $from_msg = ""; - $from_saddr = recv($self->{"fh"}, $from_msg, 1500, $flags) - or last; # For example an unreachable host will make recv() fail. - ($from_port, $from_ip) = sockaddr_in($from_saddr); - if (($from_ip eq $ip) && # Does the packet check out? - ($from_port == $self->{"port_num"}) && - ($from_msg eq $msg)) - { - $ret = 1; # It's a winner - $done = 1; - } - } - else # Oops, timed out - { - $done = 1; - } - } - return($ret); -} - -# Description: Close the connection unless we are using the tcp -# protocol, since it will already be closed. - -sub close -{ - my ($self) = @_; - - $self->{"fh"}->close() unless $self->{"proto"} eq "tcp"; -} - - -1; -__END__ - -=head1 NAME - -Net::Ping - check a remote host for reachability - -=head1 SYNOPSIS - - use Net::Ping; - - $p = Net::Ping->new(); - print "$host is alive.\n" if $p->ping($host); - $p->close(); - - $p = Net::Ping->new("icmp"); - foreach $host (@host_array) - { - print "$host is "; - print "NOT " unless $p->ping($host, 2); - print "reachable.\n"; - sleep(1); - } - $p->close(); - - $p = Net::Ping->new("tcp", 2); - while ($stop_time > time()) - { - print "$host not reachable ", scalar(localtime()), "\n" - unless $p->ping($host); - sleep(300); - } - undef($p); - - # For backward compatibility - print "$host is alive.\n" if pingecho($host); - -=head1 DESCRIPTION - -This module contains methods to test the reachability of remote -hosts on a network. A ping object is first created with optional -parameters, a variable number of hosts may be pinged multiple -times and then the connection is closed. - -You may choose one of three different protocols to use for the -ping. The "udp" protocol is the default. Note that a live remote host -may still fail to be pingable by one or more of these protocols. For -example, www.microsoft.com is generally alive but not pingable. - -With the "tcp" protocol the ping() method attempts to establish a -connection to the remote host's echo port. If the connection is -successfully established, the remote host is considered reachable. No -data is actually echoed. This protocol does not require any special -privileges but has higher overhead than the other two protocols. - -Specifying the "udp" protocol causes the ping() method to send a udp -packet to the remote host's echo port. If the echoed packet is -received from the remote host and the received packet contains the -same data as the packet that was sent, the remote host is considered -reachable. This protocol does not require any special privileges. - -It should be borne in mind that, for both tcp and udp ping, a host -will be reported as unreachable if it is not running the -appropriate echo service. For Unix-like systems see L<inetd(8)> for -more information. - -If the "icmp" protocol is specified, the ping() method sends an icmp -echo message to the remote host, which is what the UNIX ping program -does. If the echoed message is received from the remote host and -the echoed information is correct, the remote host is considered -reachable. Specifying the "icmp" protocol requires that the program -be run as root or that the program be setuid to root. - -=head2 Functions - -=over 4 - -=item Net::Ping->new([$proto [, $def_timeout [, $bytes]]]); - -Create a new ping object. All of the parameters are optional. $proto -specifies the protocol to use when doing a ping. The current choices -are "tcp", "udp" or "icmp". The default is "udp". - -If a default timeout ($def_timeout) in seconds is provided, it is used -when a timeout is not given to the ping() method (below). The timeout -must be greater than 0 and the default, if not specified, is 5 seconds. - -If the number of data bytes ($bytes) is given, that many data bytes -are included in the ping packet sent to the remote host. The number of -data bytes is ignored if the protocol is "tcp". The minimum (and -default) number of data bytes is 1 if the protocol is "udp" and 0 -otherwise. The maximum number of data bytes that can be specified is -1024. - -=item $p->ping($host [, $timeout]); - -Ping the remote host and wait for a response. $host can be either the -hostname or the IP number of the remote host. The optional timeout -must be greater than 0 seconds and defaults to whatever was specified -when the ping object was created. If the hostname cannot be found or -there is a problem with the IP number, undef is returned. Otherwise, -1 is returned if the host is reachable and 0 if it is not. For all -practical purposes, undef and 0 and can be treated as the same case. - -=item $p->close(); - -Close the network connection for this ping object. The network -connection is also closed by "undef $p". The network connection is -automatically closed if the ping object goes out of scope (e.g. $p is -local to a subroutine and you leave the subroutine). - -=item pingecho($host [, $timeout]); - -To provide backward compatibility with the previous version of -Net::Ping, a pingecho() subroutine is available with the same -functionality as before. pingecho() uses the tcp protocol. The -return values and parameters are the same as described for the ping() -method. This subroutine is obsolete and may be removed in a future -version of Net::Ping. - -=back - -=head1 WARNING - -pingecho() or a ping object with the tcp protocol use alarm() to -implement the timeout. So, don't use alarm() in your program while -you are using pingecho() or a ping object with the tcp protocol. The -udp and icmp protocols do not use alarm() to implement the timeout. - -=head1 NOTES - -There will be less network overhead (and some efficiency in your -program) if you specify either the udp or the icmp protocol. The tcp -protocol will generate 2.5 times or more traffic for each ping than -either udp or icmp. If many hosts are pinged frequently, you may wish -to implement a small wait (e.g. 25ms or more) between each ping to -avoid flooding your network with packets. - -The icmp protocol requires that the program be run as root or that it -be setuid to root. The tcp and udp protocols do not require special -privileges, but not all network devices implement the echo protocol -for tcp or udp. - -Local hosts should normally respond to pings within milliseconds. -However, on a very congested network it may take up to 3 seconds or -longer to receive an echo packet from the remote host. If the timeout -is set too low under these conditions, it will appear that the remote -host is not reachable (which is almost the truth). - -Reachability doesn't necessarily mean that the remote host is actually -functioning beyond its ability to echo packets. - -Because of a lack of anything better, this module uses its own -routines to pack and unpack ICMP packets. It would be better for a -separate module to be written which understands all of the different -kinds of ICMP packets. - -=cut |
