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@rkulla
Last active December 29, 2022 05:39
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Simple Perl-based Port Scanner
#!/usr/bin/perl
# Easy port scanner
# I wrote this in the 90s to help learn socket programming
# ./quickscan -h for usage
use Socket;
$| = 1; # so \r works right
my ($ip, $protocol, $port, $myhouse, $yourhouse, $log);
$protocol = getprotobyname('tcp');
($ip, $port, $port_stop, $log) = @ARGV;
if ($ip eq "-h") {
&usage();
}
$ip = "localhost" if not $ip;
$port = 1 if not $port;
$port_stop = 1024 if not $port_stop;
$log = "qsopenports.txt" if not $log;
unless (open(LOG_FILE, ">>$log")) {
die "Can't open log file $log for writing: $!\n"
}
# Make file handle hot so the buffer is flushed after every write
select((select(LOG_FILE), $| = 1)[0]);
print LOG_FILE "The following ports are open on $ip between port $port and $port_stop\n\n";
print "Checking $ip for open ports..\n";
for (; $port < $port_stop; $port += 1) {
socket(SOCKET, PF_INET, SOCK_STREAM, $protocol);
$yourhouse = inet_aton($ip);
$myhouse = sockaddr_in($port, $yourhouse);
if (!connect(SOCKET, $myhouse)) {
printf "%d\r", $port;
} else {
printf "%d <- open\n", $port;
print LOG_FILE "$port\n";
close SOCKET || die "close: $!";
}
}
close LOG_FILE || die "close: $!";
printf "QuickScan complete.\n";
printf "Those are the open ports for: $ip\n";
sub usage() {
print "Usage: ./quickscan [host] [start port] [stop port] [logfile]\n";
print "Defaults to localhost and port 1 and port 1024 qsopenports.txt\n";
exit 0;
}
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