Add support for IPv4 and CIDR IP ranges and other features

Hello,

Thanks for creating this app. I was actually looking for a GOlang's port scanner. Simply because of its excellent performance on threads and accuracy. And the speed is incomparable to other languages.

It would be very useful if you could add these features:

[ ] Add support for ipv4 and CIDR Ranges. For example: 123.123.12.23-123.123.12.255 123.123.0.0/17

So the command may look like this for IPv4 Ranges: scanner.exe -threads=100 -protocol=tcp -host=123.123.12.23-123.123.12.255 -ports=8080,80,443 and if CIDR used: scanner.exe -threads=500 -protocol=tcp -host=123.123.0.0/17 -ports=8080,80,443 if both type of ranges is not possible to add then IPv4 is most preferable.

[ ] Add function to save the open port results to a file (IP:Port) format. For example, the command used: scanner.exe -threads=100 -protocol=tcp -host=123.123.12.23-123.123.12.255 -ports=8080,80,443 -output=result.txt if the open ports found from IPs they will be saved as IP:Port format. If multiple open ports found from same IP, then they will be added in new line like this: 123.123.12.132:80 123.123.12.132:8080
[ ] Have option to set ranges of ports. For example: -ports=443,80,8080,9000-10000
[ ] Have option to select scan method. SYN Scan as default is most preferable.
[ ] a custom -timeout= option

Hope you could add this features. There are lots of other port scanners from different languages, but rarely on golang. These features will surely bring this go app to the top.

Best Regards

mdcg / genghiskhan

Add support for IPv4 and CIDR IP ranges and other features #1