Beta branch now available

[qbarnes]

I'm publishing a beta branch. This is to synchronize our internal repo with this repo. At this point our internal repo will be retired and replaced with this repo as upstream. Hopefully, this will prevent them getting too far out of sync in the future. Also, people won't have to report problems that have already been fixed internally and not yet published here. Lastly, everyone can try out the new code before it ends up on master.

This code is still waiting for two things before going to master:

• The code paths for IPv4 and IPv6 UDP are still untested.
• The replacement for yvipagent, dsrtools, has not yet be integrated into this repo.

Since dsrtools is not available yet, for those of you who want to test the code out, you'll need do one of the following:

• In your clone of this repo, modify line 41 in linux/kmod-xt/xt_DADDR.c from "raw" to "mangle".
• Create a file under /etc/modprobe.d. See paragraph starting at line 30 in linux/USING for details.
• Build the kmod rpm with the --with mangle option (autogenerates /etc/modprobe.d/xt_DADDR.conf file for you).

Some highlights of the beta branch:

• RHEL 4 and RHEL 5 support deprecated.
• Add option --without kmod when building rpms to prevent generating the kmod package.
• xt_DADDR's table's value (raw or mangle) can be examined by reading /sys/module/xt_DADDR/parameters/table.
• Generated source tarball suffix changed from .bz2 to .xz.
• Add RHEL 8 support.
• Remove pre and preun rpm scripts checking for kernel module.
• Fix hw csum failure for NICs using CHECKSUM_COMPLETE.
• Correct UDP checksum handling when checksum computes to 0.
• Ignore UDP checksum generation when checksum is ignored.
• Handle IPv6 ICMP packets correctly.
• No longer call kmodtool directly, but call the %kernel_module_package macro.
• Fix mock build problem when native rpmdb format is different than its chroot.
• Add --with mangle and --with override rpm build options.
• Support 5.3 and later kernels with skb_ensure_writable().
• Add support for the make macro DESTDIR.

[dmitris]

The replacement for yvipagent, dsrtools, has not yet be integrated into this repo.

see #13 - since the beta branch now has dsrtools - https://github.com/yahoo/l3dsr/tree/beta/linux/dsrtools - the first "waiting for" TODO can be "crossed out".

@qbarnes @wbadger @jschauma - do you think the other item - "The code paths for IPv4 and IPv6 UDP are still untested." - is still relevant? What should be the roadmap toward merging this into master and what are the blockers on that road, if any? Maybe we should create separate issues for such blockers to make it easier to focus on them.