Added support for tunneling netlink attrributes (ipip, gre, sit).
These works with kernel module ipip, gre and sit . The test cases are
moved to a separate file and manual test as well because they require
respective kernel modules as well.
Firstly, remove stray assert(). Also be a bit stricter when verifying the
received info. If we get an applicable newlink message that we can't make
sense of, we will now enter NETDEV_FAILED, as we cannot reasonably continue
without knowing the ifindex of our device.
tcpwrap is legacy code, that is barely maintained upstream. It's APIs
are awful, and the feature set it exposes (such as DNS and IDENT
access control) questionnable. We should not support this natively in
systemd.
Hence, let's remove the code. If people want to continue making use of
this, they can do so by plugging in "tcpd" for the processes they start.
With that scheme things are as well or badly supported as they were from
traditional inetd, hence no functionality is really lost.
Given that native services do not carry a sysv priority anyway it is
pointless reading them from chkconfig headers, and pretend they'd work.
So let's drop this.
Extend rta_offset_tb into a stack of offset tables, one for each parent of the
current container, and make sd_rtnl_message_{enter,exit}_container() pop/push
to this stack.
Also make sd_rtnl_message_rewind() parse the top-level container, and use this
when reading a message from the socket.
This changes the API by dropping the now redundant sd_rtnl_message_read()
method.
Update comment to be a bit more specific.
Change match to blacklist the serial number of the broken devices
instead of whitelisting the serial number of the fixed devices.
This allows to do something useful with the serial number in the
future.
safe_close_pair() is more like safe_close(), except that it handles
pairs of fds, and doesn't make and misleading allusion, as it works
similarly well for socketpairs() as for pipe()s...
If you allocate a message with bus==NULL and then unref the main bus,
it will free your message underneath and your program will go boom!
To fix that, we really need to figure out what the semantics for
self-references (m->bus) should be and when/where/what accesses are
actually allowed.
Same is true for the pseudo-thread-safety we employ..
In sd_bus_unref() we check for self-reference loops and destruct our
queues in case we're the only reference holders. However, we do _not_
modify our own ref-count, thus effectively causing the
message-destructions to enter with the same reference count as we did.
The only reason this doesn't cause an endless recursion (or trigger
assert(m->n_ref > 0) in sd_bus_message_unref()) is the fact that we
decrease queue-counters _before_ calling _unref(). That's not obvious at
all, so add a big fat note in bus_reset_queues() to everyone touching that
code.
Like sd-bus, sd-rtnl can have self-references through queued messages. In
particular, each queued message has the following self-ref loop:
rtnl->wqueue[i]->rtnl == rtnl
Same is true for "rqueue".
When sd_rtnl_unref() gets called, we must therefore make sure we correctly
consider each self-reference when deciding to destroy the object. For each
queued message, there _might_ be one ref. However, rtnl-messages can be
created _without_ a bus-reference, therefore we need to verify the
actually required ref-count.
Once we know exactly how many self-refs exist, and we verified none of the
queued messages has external references, we can destruct the object.
We must immediately drop our own reference, then flush all queues and
destroy the bus object. Otherwise, each sd_rtnl_message_unref() call would
recurse into the same destruction logic as they enter with the same
rtnl-refcnt.
Note: We really should verify _all_ queued messages have m->rtnl set to
the bus they're queued on. If that's given, we can change:
if (REFCNT_GET(rtnl->n_ref) <= refs)
to
if (REFCNT_GET(rtnl->n_ref) == refs)
and thus avoid recalculating the required refs for each message we
remove from the queue during destruction.
One end of the socketpair is closed by the library, so only close our end. Also switch to
the safe_close() so we get notified about problems with closing.
