Enabling IP Packet Sending/Receiving in Swift Without Root Privilege

Related Projects SwiftNIO
1

I've been working with NIORawSocketBootstrap to send and receive IP packets, such as ICMP pings, in Swift. However, I've encountered an issue: this approach requires root privileges on macOS and Linux. I'm wondering if there's a way to achieve similar functionality while using .datagram as the socketType and still supporting various protocolSubtype , such as .icmp .

In my current local fork of swift-nio, I have the following code snippet in the makeChannel() function:

return try DatagramChannel(eventLoop: eventLoop,
                            protocolFamily: address.protocol,
                            protocolSubtype: .init(ipProtocol),
                            socketType: .datagram)

Is there a way to make this work without requiring root privilege? If not, do you have any suggestions or alternatives for sending and receiving IP packets securely in Swift? I appreciate any insights!

Thanks in advance!

2

Unfortunately I believe sending raw IP packets always requires root privilege.

3

The only alternative I can think of is spawning a utun, I believe that doesn't require root. If you are able to give it an IP, it could do the communication for you. But it's quite some fiddling.

4

Thank you for the clarification. In the context of ICMP , I'm curious if Swift-NIO currently supports or plans to support socket capabilities for both root and non-root users, similar to the functionality available in C.

Regarding the NIORawSocketBootstrap , it would be more user-friendly if it allowed user to select socketType (.raw or .datagram ) rather than being fixed on a raw socket as it currently is.

For instance, in C, you can achieve this functionality for non-root users with the following code:

socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP) // for non-root user

Swift-NIO currently supports the following in NIORawSocketBootstrap

socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);

Thanks!

5

Thanks for the suggestion!

6

Yes, we'd be open to adding this support. Can you file an issue please?

1 Like
7

sounds good!