the filter as we do from bpf_filter()[1].
- Revert experimental use of contigmalloc(9)/contigfree(9). It has no
performance benefit over malloc(9)/free(9)[2].
Requested by: rwatson[1]
Pointed out by: rwatson, jhb, alc[2]
the generated binary and remove page size limitation for userland.
- Use contigmalloc(9)/contigfree(9) instead of malloc(9)/free(9) to make
sure the generated binary aligns properly and make it physically contiguous.
Previously it may have contained unnecessary (even sensitive) data from
the previous allocation.
As a (good) side effect, scratch memory may be used to store the previous
filter state(s) safely because it is allocated and freed with filter itself.
However, use it carefully because bpf_filter(9) does not have this behavior.
MFC after: 3 days
Use the following kernel configuration option to enable:
options BPF_JITTER
If you want to use bpf_filter() instead (e. g., debugging), do:
sysctl net.bpf.jitter.enable=0
to turn it off.
Currently BIOCSETWF and bpf_mtap2() are unsupported, and bpf_mtap() is
partially supported because 1) no need, 2) avoid expensive m_copydata(9).
Obtained from: WinPcap 3.1 (for i386)
