Allow libpcap to read files with some additional link-layer type values

patch has been contributed by Guy Harris from libpcap/tcpdump. It
resolves collision between DLT_* values on various OSes. The issue
prevents correct interpretation of link layer information in capture
files which might come from another OS. To resolve this libpcap/tcpdump
community introduced a LINKTYPE_* values. The patch provides translation
between DLT_* and LINKTYPE_* for OpenBSD. More details can be found
here: https://www.tcpdump.org/linktypes.html

No objection from OpenBSD community.

OK sthen@

add support for pcap_breakloop when reading packets from files.

djm pulled support in for pcap_breakloop on the bpf side of things,
this makes it work when reading files too.

from Caspar Schutijser
lteo@ seems keen
ok djm@

remove NULL-checks before free()

Remove register keyword.

ok deraadt@

memory.h -> string.h

ok deraadt@

Remove pointless casts for several malloc/calloc/free calls. No object
file change.

Remove pointless casts. No binary change.

suggested by krw@

Change a few malloc+memset calls to calloc.

ok deraadt@ florian@

Import a number of core functions from libpcap-1.2.0 while preserving
local changes: strncpy() -> strlcpy(), malloc(x * y) -> calloc(x, y),
exclude cross-platform cruft, etc.

The new functions are pcap_create(), pcap_set_snaplen(),
pcap_set_promisc(), pcap_can_set_rfmon(), pcap_set_rfmon(),
pcap_set_timeout(), pcap_set_buffer_size(), pcap_activate(), and
pcap_statustostr().

This diff was tested on amd64, i386, macppc, and sparc64, where
regression tests were done on various pcap-based ports (especially amd64
and i386 where regression tests were run on all pcap-based ports).
Testers also tried running pcap-based ports that they are familiar with
to ensure that there is no behavioral change. tcpdump and pflogd in
base were also tested by different testers. The new pcap_* functions
were tested with a proof-of-concept Snort 2.9 port for many months.

Thank you to everyone who helped test this diff and provided feedback:
haesbaert@, sthen@, matthew@, gonzalo@, brett@, Rodolfo Gouveia,
Aaron Bieber, Markus Lude, and Ray Percival.

ok haesbaert sthen henning

add remaining tcpdump.org libpcap 0.9 APIs, most notably
pcap_setdirection() (which depends on the kernel-side bpf changes
committed yesterday); ok canacar@

remove $Header, it was messing up cvs for me. ok deraadt@

changes brought in from v0.4; started by brad, more by me, being tested by mts

if pcap_dump_open() specified a snaplen of -1, make sure pcap_open_offline() does not malloc -1, but uses max snaplen; pointed out by mts@nfr.net

buf oflows

bring it to the latest 0.2 LBL release.

merge to latest libpcap

Update to the latest LBL release.

branches: 1.1.1;
Initial revision

add support for pcap_breakloop when reading packets from files.

djm pulled support in for pcap_breakloop on the bpf side of things,
this makes it work when reading files too.

from Caspar Schutijser
lteo@ seems keen
ok djm@

remove NULL-checks before free()

Remove register keyword.

ok deraadt@

memory.h -> string.h

ok deraadt@

Remove pointless casts for several malloc/calloc/free calls. No object
file change.

Remove pointless casts. No binary change.

suggested by krw@

Change a few malloc+memset calls to calloc.

ok deraadt@ florian@

Import a number of core functions from libpcap-1.2.0 while preserving
local changes: strncpy() -> strlcpy(), malloc(x * y) -> calloc(x, y),
exclude cross-platform cruft, etc.

The new functions are pcap_create(), pcap_set_snaplen(),
pcap_set_promisc(), pcap_can_set_rfmon(), pcap_set_rfmon(),
pcap_set_timeout(), pcap_set_buffer_size(), pcap_activate(), and
pcap_statustostr().

This diff was tested on amd64, i386, macppc, and sparc64, where
regression tests were done on various pcap-based ports (especially amd64
and i386 where regression tests were run on all pcap-based ports).
Testers also tried running pcap-based ports that they are familiar with
to ensure that there is no behavioral change. tcpdump and pflogd in
base were also tested by different testers. The new pcap_* functions
were tested with a proof-of-concept Snort 2.9 port for many months.

Thank you to everyone who helped test this diff and provided feedback:
haesbaert@, sthen@, matthew@, gonzalo@, brett@, Rodolfo Gouveia,
Aaron Bieber, Markus Lude, and Ray Percival.

ok haesbaert sthen henning

add remaining tcpdump.org libpcap 0.9 APIs, most notably
pcap_setdirection() (which depends on the kernel-side bpf changes
committed yesterday); ok canacar@

remove $Header, it was messing up cvs for me. ok deraadt@

changes brought in from v0.4; started by brad, more by me, being tested by mts

if pcap_dump_open() specified a snaplen of -1, make sure pcap_open_offline() does not malloc -1, but uses max snaplen; pointed out by mts@nfr.net

buf oflows

bring it to the latest 0.2 LBL release.

merge to latest libpcap

Update to the latest LBL release.

branches: 1.1.1;
Initial revision