NetBSD/lib/libpcap
cgd 7ff54a795e lint 1997-11-05 21:37:27 +00:00
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CHANGES Resolve conflicts 1997-10-03 15:53:00 +00:00
Makefile use CPPFLAGS instead of CFLAGS 1997-10-23 02:53:50 +00:00
README Resolve conflicts 1997-10-03 15:53:00 +00:00
bpf_image.c Resolve conflicts 1997-10-03 15:53:00 +00:00
etherent.c Resolve conflicts 1997-10-03 15:53:00 +00:00
ethertype.h Resolve conflicts 1997-10-03 15:53:00 +00:00
gencode.c Resolve conflicts 1997-10-03 15:53:00 +00:00
gencode.h Resolve conflicts 1997-10-03 15:53:00 +00:00
gnuc.h Resolve conflicts 1997-10-03 15:53:00 +00:00
grammar.y Resolve conflicts 1997-10-03 15:53:00 +00:00
inet.c Resolve conflicts 1997-10-03 15:53:00 +00:00
nametoaddr.c lint 1997-11-05 21:37:27 +00:00
optimize.c Resolve conflicts 1997-10-03 15:53:00 +00:00
pcap-bpf.c Resolve conflicts 1997-10-03 15:53:00 +00:00
pcap-int.h Resolve conflicts 1997-10-03 15:53:00 +00:00
pcap-namedb.h Resolve conflicts 1997-10-03 15:53:00 +00:00
pcap.3 xref tcpdump(8) not nonexistent tcpdump(8); remove tcpslice(1) xrefs 1997-10-18 06:57:59 +00:00
pcap.c Resolve conflicts 1997-10-03 15:53:00 +00:00
pcap.h Resolve conflicts 1997-10-03 15:53:00 +00:00
pcap2netbsd add dependancies so that "make depend" isn't required, remove WARNS from here 1997-10-09 12:43:57 +00:00
ppp.h Import LBL's libpcap 0.4a3 1997-10-03 15:38:55 +00:00
savefile.c Resolve conflicts 1997-10-03 15:53:00 +00:00
scanner.l Resolve conflicts 1997-10-03 15:53:00 +00:00
shlib_version Port to NetBSD, and add NetBSD RCS tags. 1995-03-06 11:37:58 +00:00
version.c Add support for version.c; this is needed by other programs. 1997-10-03 16:40:56 +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