NetBSD/lib/libpcap
itojun 4a7fa50e38 always write out and read in files using 32bit timeval.
(if you have files written by 64bit arch, sorry, we can't read
those... there's no magic number or anything like that)
sync with tcpdump.org change.
2001-02-07 17:35:56 +00:00
..
CHANGES
Makefile
README
bpf_image.c Format string cleanups by sommerfeld. 2000-10-10 19:12:48 +00:00
etherent.c
ethertype.h
gencode.c Add VRRP support. 2001-01-19 09:02:40 +00:00
gencode.h Add VRRP support. 2001-01-19 09:02:40 +00:00
gnuc.h
grammar.y Add VRRP support. 2001-01-19 09:02:40 +00:00
inet.c
nametoaddr.c
optimize.c remove redundant declarations. 2001-01-06 02:11:18 +00:00
pcap-bpf.c
pcap-int.h always write out and read in files using 32bit timeval. 2001-02-07 17:35:56 +00:00
pcap-namedb.h
pcap.3 Add pcap_compile_nopcap() from the most recent libpcap release 2000-10-06 16:39:24 +00:00
pcap.c
pcap.h remove redundant declarations. 2001-01-06 02:11:18 +00:00
pcap2netbsd
ppp.h
savefile.c always write out and read in files using 32bit timeval. 2001-02-07 17:35:56 +00:00
scanner.l Add VRRP support. 2001-01-19 09:02:40 +00:00
shlib_version Add pcap_compile_nopcap() from the most recent libpcap release 2000-10-06 16:39:24 +00:00
version.c we already have all fixes toward 0.4 (v0.4 Sat Jul 25 12:40:09 PDT 1998 - 2000-10-08 14:28:05 +00:00

README

$NetBSD: README,v 1.4 1997/10/03 15:53:01 christos Exp $
@(#) Header: README,v 1.18 97/06/12 14:23:56 leres Exp  (LBL)

LIBPCAP 0.4
Lawrence Berkeley National Laboratory
Network Research Group
libpcap@ee.lbl.gov
ftp://ftp.ee.lbl.gov/libpcap.tar.Z

This directory contains source code for libpcap, a system-independent
interface for user-level packet capture.  libpcap provides a portable
framework for low-level network monitoring.  Applications include
network statistics collection, security monitoring, network debugging,
etc.  Since almost every system vendor provides a different interface
for packet capture, and since we've developed several tools that
require this functionality, we've created this system-independent API
to ease in porting and to alleviate the need for several
system-dependent packet capture modules in each application.

Note well: this interface is new and is likely to change.

The libpcap interface supports a filtering mechanism based on the
architecture in the BSD packet filter.  BPF is described in the 1993
Winter Usenix paper ``The BSD Packet Filter: A New Architecture for
User-level Packet Capture''.  A compressed postscript version is in:

	ftp://ftp.ee.lbl.gov/papers/bpf-usenix93.ps.Z.

Although most packet capture interfaces support in-kernel filtering,
libpcap utilizes in-kernel filtering only for the BPF interface.
On systems that don't have BPF, all packets are read into user-space
and the BPF filters are evaluated in the libpcap library, incurring
added overhead (especially, for selective filters).  Ideally, libpcap
would translate BPF filters into a filter program that is compatible
with the underlying kernel subsystem, but this is not yet implemented.

BPF is standard in 4.4BSD, BSD/386, NetBSD, and FreeBSD.  DEC OSF/1
uses the packetfilter interface but has been extended to accept BPF
filters (which libpcap utilizes).  Also, you can add BPF filter support
to Ultrix using the kernel source and/or object patches available in:

	ftp://gatekeeper.dec.com/pub/DEC/net/bpfext42.tar.Z.

Problems, bugs, questions, desirable enhancements, source code
contributions, etc., should be sent to the email address
"libpcap@ee.lbl.gov".

 - Steve McCanne
   Craig Leres
   Van Jacobson