ppp support

[felixonmars]

Seems like ppp interfaces are not supported now:

$ sniffglue ppp0
Listening on device: "ppp0", verbosity 0/4
Error: Unknown link type: 113 

[kpcyrd]

hi!

the link type can be added here: https://github.com/kpcyrd/sniffglue/blob/main/src/link.rs

If ppp emits plain ethernet frames it can be added relatively easily here:

sniffglue/src/centrifuge/mod.rs

Lines 26 to 37 in 7c2c376

	pub fn parse(link: &DataLink, data: &[u8]) -> raw::Raw {
	match *link {
	DataLink::Ethernet => match parse_eth(data) {
	Ok(eth) => eth,
	Err(_) => Unknown(data.to_vec()),
	},
	DataLink::Tun => parse_tun(data),
	DataLink::RadioTap => {
	Unknown(data.to_vec())
	},
	}
	}

If you have either instructions on how to easily create a ppp device to test with, or a pcap file, that'd be very useful for implementing support. :)

Thanks!

[felixonmars]

ppp0.pcap.gz

I'm not familiar with the internals either, hope this pcap file helps :)