Preventing other applications from using a port
One of my applications uses randomly-selected ports from a port range to listen on. By default, 40000-59999.
The application runs on a firewalled server, and of course expects me to open the whole range on the firewall.
I'm not comfortable opening a large range of ports, most of which will never be used. The main concern is that another application may, also randomly, choose a port in that range and end up open to the world. I can configure the port range to be smaller, which would reduce the problem somewhat, but not truly solve it.
I have two ideas how to solve this conceptually, but don't know how/if it can actually be implemented. Operating system is RedHat Linux 7.4. The firewall is iptables/firewalld. SELinux is disabled (yes, I know, I don't like that either...)
My first idea: somehow "magically" prevent all other applications from binding to ports in this range. SELinux might be able to do that, but unfortunately I cannot use SELinux on that server (another application chokes on it).
My second idea: somehow get iptables to open ports by executable instead of by port number. This is a feature in the Windows firewall, but I don't think I have seen a way to do this with iptables.
What I'm looking for is ideas for implementing either of my ideas, or a third approach.
linux iptables
asked 21 mins ago
Kevin Keane
325111
add a comment |
One of my applications uses randomly-selected ports from a port range to listen on. By default, 40000-59999.
The application runs on a firewalled server, and of course expects me to open the whole range on the firewall.
I'm not comfortable opening a large range of ports, most of which will never be used. The main concern is that another application may, also randomly, choose a port in that range and end up open to the world. I can configure the port range to be smaller, which would reduce the problem somewhat, but not truly solve it.
I have two ideas how to solve this conceptually, but don't know how/if it can actually be implemented. Operating system is RedHat Linux 7.4. The firewall is iptables/firewalld. SELinux is disabled (yes, I know, I don't like that either...)
My first idea: somehow "magically" prevent all other applications from binding to ports in this range. SELinux might be able to do that, but unfortunately I cannot use SELinux on that server (another application chokes on it).
My second idea: somehow get iptables to open ports by executable instead of by port number. This is a feature in the Windows firewall, but I don't think I have seen a way to do this with iptables.
What I'm looking for is ideas for implementing either of my ideas, or a third approach.
linux iptables
asked 21 mins ago
Kevin Keane
325111
add a comment |
One of my applications uses randomly-selected ports from a port range to listen on. By default, 40000-59999.
The application runs on a firewalled server, and of course expects me to open the whole range on the firewall.
I'm not comfortable opening a large range of ports, most of which will never be used. The main concern is that another application may, also randomly, choose a port in that range and end up open to the world. I can configure the port range to be smaller, which would reduce the problem somewhat, but not truly solve it.
I have two ideas how to solve this conceptually, but don't know how/if it can actually be implemented. Operating system is RedHat Linux 7.4. The firewall is iptables/firewalld. SELinux is disabled (yes, I know, I don't like that either...)
My first idea: somehow "magically" prevent all other applications from binding to ports in this range. SELinux might be able to do that, but unfortunately I cannot use SELinux on that server (another application chokes on it).
My second idea: somehow get iptables to open ports by executable instead of by port number. This is a feature in the Windows firewall, but I don't think I have seen a way to do this with iptables.
What I'm looking for is ideas for implementing either of my ideas, or a third approach.
linux iptables
asked 21 mins ago
Kevin Keane
325111
One of my applications uses randomly-selected ports from a port range to listen on. By default, 40000-59999.
The application runs on a firewalled server, and of course expects me to open the whole range on the firewall.
I'm not comfortable opening a large range of ports, most of which will never be used. The main concern is that another application may, also randomly, choose a port in that range and end up open to the world. I can configure the port range to be smaller, which would reduce the problem somewhat, but not truly solve it.
I have two ideas how to solve this conceptually, but don't know how/if it can actually be implemented. Operating system is RedHat Linux 7.4. The firewall is iptables/firewalld. SELinux is disabled (yes, I know, I don't like that either...)
My first idea: somehow "magically" prevent all other applications from binding to ports in this range. SELinux might be able to do that, but unfortunately I cannot use SELinux on that server (another application chokes on it).
My second idea: somehow get iptables to open ports by executable instead of by port number. This is a feature in the Windows firewall, but I don't think I have seen a way to do this with iptables.
What I'm looking for is ideas for implementing either of my ideas, or a third approach.
linux iptables
linux iptables
asked 21 mins ago
Kevin Keane
325111
asked 21 mins ago
Kevin Keane
325111
asked 21 mins ago
Kevin Keane
325111
asked 21 mins ago
Kevin Keane
325111
asked 21 mins ago
Kevin Keane
325111
325111
add a comment |
add a comment |
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