Ticket #17: sockstat.pl

#!/usr/bin/perl -w
#-
# Copyright (c) 1999 Dag-Erling Coïdan Smørgrav
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer
#    in this position and unchanged.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. The name of the author may not be used to endorse or promote products
#    derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# $FreeBSD: src/usr.bin/sockstat/sockstat.pl,v 1.16 2002/04/22 13:44:39 des Exp $
#

use strict;
use Getopt::Std;

my %netstat;
my %fstat;
my $unknown = [ "?", "?", "?", "?", "?", "?", "?", "?", "?" ];

my $inet_fmt = "%-8.8s %-8.8s %5.5s %4.4s %-6.6s %-21.21s %-21.21s\n";
my $unix_fmt = "%-8.8s %-8.8s %5.5s %4.4s %-6.6s %-43.43s\n";

my @ranges;

#
# Parse a port range specification
#
sub parse_port_ranges($) {
    my $spec = shift;           # Range spec

    my $range;                  # Range
    my ($low, $high);           # Low/high ends of range

    foreach $range (split(/\s*,\s*/, $spec)) {
        if ($range =~ m/^(\d+)-(\d+)$/) {
            ($low, $high) = ($1, $2);
        } elsif ($range =~ m/^-(\d+)$/) {
            ($low, $high) = (1, $1);
        } elsif ($range =~ m/^(\d+)-$/) {
            ($low, $high) = ($1, 65535);
        } elsif ($range =~ m/^(\d+)$/) {
            $low = $high = $1;
        } else {
            die("invalid range specification: $range\n");
        }
        if ($low < 0 || $low > 65535 || $high < 0 || $high > 65535) {
            die("valid ports numbers are 1-65535 inclusive\n");
        }
        if ($low > $high) {
            $low ^= $high;
            $high ^= $low;
            $low ^= $high;
        }
        push(@ranges, [ $low, $high ]);
    }
}

#
# Check if a port is in an allowed range
#
sub check_range($) {
    my $addr = shift;           # Address to check

    my $port;                   # Port number
    my $range;                  # Range
    
    if (@ranges == 0) {
        return 1;
    }

    if ($addr !~ m/\.(\d+)$/) {
        return undef;
    }
    $port = $1;

    foreach $range (@ranges) {
        if ($port >= $range->[0] && $port <= $range->[1]) {
            return 1;
        }
    }
    return undef;
}

#
# Gather information about sockets
#
sub gather() {
    
    local *PIPE;                # Pipe
    my $pid;                    # Child PID
    my $line;                   # Input line
    my @fields;                 # Fields

    # Netstat
    if (!defined($pid = open(PIPE, "-|"))) {
        die("open(netstat): $!\n");
    } elsif ($pid == 0) {
        exec("/usr/sbin/netstat", "-Aan");
        die("exec(netstat): $!\n");
    }
    while ($line = <PIPE>) {
        next unless ($line =~ m/^ [0-9a-f]{7} /) || ($line =~ m/^[0-9a-f]{16} /);
        chomp($line);
        @fields = split(' ', $line);
        $netstat{$fields[0]} = [ @fields ];
    }
    close(PIPE)
        or die("close(netstat): $!\n");

    # Fstat
    if (!defined($pid = open(PIPE, "-|"))) {
        die("open(fstat): $!\n");
    } elsif ($pid == 0) {
        exec("/usr/bin/fstat");
        die("exec(fstat): $!\n");
    }
    while ($line = <PIPE>) {
        chomp($line);
        @fields = split(' ', $line);
        next if ($fields[4] eq "-");
        push(@{$fstat{$fields[4]}}, [ @fields ]);
    }
    close(PIPE)
        or die("close(fstat): $!\n");
}

#
# Replace the last dot in an "address.port" string with a colon
#
sub addr($) {
    my $addr = shift;           # Address

    $addr =~ s/^(.*)\.([^\.]*)$/$1:$2/;
    return $addr;
}

#
# Print information about Internet sockets
#
sub print_inet($$$) {
    my $af = shift;             # Address family
    my $conn = shift || 0;      # Show connected sockets
    my $listen = shift || 0;    # Show listen sockets

    my $fsd;                    # Fstat data
    my $nsd;                    # Netstat data

    printf($inet_fmt, "USER", "COMMAND", "PID", "FD",
           "PROTO", "LOCAL ADDRESS", "FOREIGN ADDRESS");
    foreach $fsd (@{$fstat{$af}}) {
        next unless defined($fsd->[7]);
        $nsd = $netstat{$fsd->[7]} || $unknown;
        next unless (check_range($nsd->[4]) || check_range($nsd->[5]));
        next if (!$conn && $nsd->[5] ne '*.*');
        next if (!$listen && $nsd->[5] eq '*.*');
        printf($inet_fmt, $fsd->[0], $fsd->[1], $fsd->[2],
               substr($fsd->[3], 0, -1),
               $nsd->[1], addr($nsd->[4]), addr($nsd->[5]));
    }
    print("\n");
}

#
# Print information about Unix domain sockets
#
sub print_unix($$) {
    my $conn = shift || 0;      # Show connected sockets
    my $listen = shift || 0;    # Show listen sockets

    my %endpoint;               # Mad PCB to process/fd
    my $fsd;                    # Fstat data
    my $nsd;                    # Netstat data

    foreach $fsd (@{$fstat{"unix"}}) {
        $endpoint{$fsd->[6]} = "$fsd->[1]\[$fsd->[2]\]:" .
            substr($fsd->[3], 0, -1);
    }
    printf($unix_fmt, "USER", "COMMAND", "PID", "FD", "PROTO", "ADDRESS");
    foreach $fsd (@{$fstat{"unix"}}) {
        next unless defined($fsd->[6]);
        next if (!$conn && defined($fsd->[8]));
        next if (!$listen && !defined($fsd->[8]));
        $nsd = $netstat{$fsd->[6]} || $unknown;
        printf($unix_fmt, $fsd->[0], $fsd->[1], $fsd->[2],
               substr($fsd->[3], 0, -1), $fsd->[5],
               $nsd->[8] || ($fsd->[8] ? $endpoint{$fsd->[8]} : "(none)"));
    }
    print("\n");
}

#
# Print usage message and exit
#
sub usage() {
    print(STDERR "usage: sockstat [-46clu] [-p ports]\n");
    exit(1);
}

MAIN:{
    my %opts;                   # Command-line options

    getopts("46clp:u", \%opts)
        or usage();

    gather();

    if (!$opts{'4'} && !$opts{'6'} && !$opts{'u'}) {
        $opts{'4'} = $opts{'6'} = $opts{'u'} = 1;
    }
    if (!$opts{'c'} && !$opts{'l'}) {
        $opts{'c'} = $opts{'l'} = 1;
    }
    if ($opts{'p'}) {
        parse_port_ranges($opts{'p'});
    }
    if ($opts{'4'}) {
        print_inet("internet", $opts{'c'}, $opts{'l'});
    }
    if ($opts{'6'}) {
        print_inet("internet6", $opts{'c'}, $opts{'l'});
    }
    if ($opts{'u'}) {
        print_unix($opts{'c'}, $opts{'l'});
    }
    
    exit(0);
}