This file was never truly necessary and has never actually been used in
the history of Tailscale's open source releases.
A Brief History of AUTHORS files
---
The AUTHORS file was a pattern developed at Google, originally for
Chromium, then adopted by Go and a bunch of other projects. The problem
was that Chromium originally had a copyright line only recognizing
Google as the copyright holder. Because Google (and most open source
projects) do not require copyright assignemnt for contributions, each
contributor maintains their copyright. Some large corporate contributors
then tried to add their own name to the copyright line in the LICENSE
file or in file headers. This quickly becomes unwieldy, and puts a
tremendous burden on anyone building on top of Chromium, since the
license requires that they keep all copyright lines intact.
The compromise was to create an AUTHORS file that would list all of the
copyright holders. The LICENSE file and source file headers would then
include that list by reference, listing the copyright holder as "The
Chromium Authors".
This also become cumbersome to simply keep the file up to date with a
high rate of new contributors. Plus it's not always obvious who the
copyright holder is. Sometimes it is the individual making the
contribution, but many times it may be their employer. There is no way
for the proejct maintainer to know.
Eventually, Google changed their policy to no longer recommend trying to
keep the AUTHORS file up to date proactively, and instead to only add to
it when requested: https://opensource.google/docs/releasing/authors.
They are also clear that:
> Adding contributors to the AUTHORS file is entirely within the
> project's discretion and has no implications for copyright ownership.
It was primarily added to appease a small number of large contributors
that insisted that they be recognized as copyright holders (which was
entirely their right to do). But it's not truly necessary, and not even
the most accurate way of identifying contributors and/or copyright
holders.
In practice, we've never added anyone to our AUTHORS file. It only lists
Tailscale, so it's not really serving any purpose. It also causes
confusion because Tailscalars put the "Tailscale Inc & AUTHORS" header
in other open source repos which don't actually have an AUTHORS file, so
it's ambiguous what that means.
Instead, we just acknowledge that the contributors to Tailscale (whoever
they are) are copyright holders for their individual contributions. We
also have the benefit of using the DCO (developercertificate.org) which
provides some additional certification of their right to make the
contribution.
The source file changes were purely mechanical with:
git ls-files | xargs sed -i -e 's/\(Tailscale Inc &\) AUTHORS/\1 contributors/g'
Updates #cleanup
Change-Id: Ia101a4a3005adb9118051b3416f5a64a4a45987d
Signed-off-by: Will Norris <will@tailscale.com>
Instead of changing the working directory before launching the incubator process,
this now just changes the working directory after dropping privileges, at which
point we're more likely to be able to enter the user's home directory since we're
running as the user.
For paths that use the 'login' or 'su -l' commands, those already take care of changing
the working directory to the user's home directory.
Fixes#13120
Signed-off-by: Percy Wegmann <percy@tailscale.com>
This allows pam authentication to run for ssh sessions, triggering
automation like pam_mkhomedir.
Updates #11854
Signed-off-by: Percy Wegmann <percy@tailscale.com>
On FreeBSD and Darwin, changing a process's supplementary groups with
setgroups(2) will also change the egid of the process, setting it to the
first entry in the provided list. This is distinct from the behaviour on
other platforms (and possibly a violation of the POSIX standard).
Because of this, on FreeBSD with no TTY, our incubator code would
previously not change the process's gid, because it would read the
newly-changed egid, compare it against the expected egid, and since they
matched, not change the gid. Because we didn't use the 'login' program
on FreeBSD without a TTY, this would propagate to a child process.
This could be observed by running "id -p" in two contexts. The expected
output, and the output returned when running from a SSH shell, is:
andrew@freebsd:~ $ id -p
uid andrew
groups andrew
However, when run via "ssh andrew@freebsd id -p", the output would be:
$ ssh andrew@freebsd id -p
login root
uid andrew
rgid wheel
groups andrew
(this could also be observed via "id -g -r" to print just the gid)
We fix this by pulling the details of privilege dropping out into their
own function and prepending the expected gid to the start of the list on
Darwin and FreeBSD.
Finally, we add some tests that run a child process, drop privileges,
and assert that the final UID/GID/additional groups are what we expect.
More information can be found in the following article:
https://www.usenix.org/system/files/login/articles/325-tsafrir.pdf
Updates #7616
Alternative to #7609
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I0e6513c31b121108b50fe561c89e5816d84a45b9
