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Subject: Re: BPF_MISC+BPF_COP and BPF_COPX
From: Guy Harris <guy@alum.mit.edu>
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On Aug 8, 2013, at 1:14 AM, Darren Reed <darrenr@netbsd.org> wrote:

> A BPF program generated on Linux is just as valid as on Solaris or =
NetBSD.

Not necessarily - negative offsets in load and store instructions are =
supported on Linux to access some metadata that's not in the packet =
data, but those aren't, as far as I know, supported on other platforms.

However, there is a subset of BPF that all kernel BPF implementations, =
and the userland implementation in libpcap, support.=