LIBPCAP 1.x.y by The Tcpdump Group

To report a security issue please send an e-mail to security@tcpdump.org.

To report bugs and other problems, contribute patches, request a feature, provide generic feedback etc please see the guidelines for contributing.

The documentation directory has README files about specific operating systems and options.

Anonymous Git is available via:

https://github.com/the-tcpdump-group/libpcap.git

From version 0.4, library versioning will use a semantic versioning format (per http://semver.org) of the form Major.minor.patch (M.m.p).

formerly from 	Lawrence Berkeley National Laboratory
		Network Research Group <libpcap@ee.lbl.gov>
		ftp://ftp.ee.lbl.gov/old/libpcap-0.4a7.tar.Z

Support for particular platforms and BPF

For some platforms there are README.{system} files that discuss issues with the OS's interface for packet capture on those platforms, such as how to enable support for that interface in the OS, if it's not built in by default.

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'' (compressed PostScript, gzipped PostScript, PDF).

• ITM software trace - packet processing and decode.
• ETMv3 data trace - packet decode.
• ETMv4 data trace - packet processing and decode.

BPF is standard in 4.4BSD, BSD/OS, NetBSD, FreeBSD, OpenBSD, DragonFly BSD, macOS, and Solaris 11; an older, modified and undocumented version is standard in AIX. {DEC OSF/1, Digital UNIX, Tru64 UNIX} uses the packetfilter interface but has been extended to accept BPF filters (which libpcap utilizes).

Linux has a number of BPF based systems, and libpcap does not support any of the eBPF mechanisms as yet, although it supports many of the memory mapped receive mechanisms. See the Linux-specific README for more information.

Note to Linux distributions and *BSD systems that include libpcap:

CoreSight kernel drivers and perf suport for CoreSight trace is maintained in the latest upstream kernel versions.

It sets the soname of the library to libpcap.so.1; this is what it should be, NOT libpcap.so.1.x or libpcap.so.1.x.y or something such as that.

We've been maintaining binary compatibility between libpcap releases for quite a while; there's no reason to tie a binary linked with libpcap to a particular release of libpcap.