Using libpcap:s pcap_compile() in bpf.c?

[Erik Alapää]

Hello! I am building a modified DHCP relay/proxy based on the ISC
relay code, version 3.0.2 (project started before 3.0.3 was released,
will merge in our local cvs later)

Now my questions: I want to use the pcap_compile() function from
libpcap to create a modified packet filter.

1. Is there any good documentation out there, except for the pcap
manpage? (Linux-only is good, examples portable to Solaris and BSD
even better)

2. How do I get a pcap_t handle for pcap_compile(), the relay code
seems to bypass libpcap and open() a pfilt device directly and use
some
ioctl() magic? There is quite a lot of conditional compilation going
on too, which complicates my attempt to understand the code.

3. Can I somehow just create a filter with pcap_compile() without
doing all the other libpcap stuff, and then force-feed this filter
into the existing relay code?

Best regards,

/Erik Alapää


--
Erik Alapää
Software Engineer M. Sc., Lic. Ind. Math.

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