A bug exists where the conflict counter is cleared
regardless of whether or not the next probe attempt leads to
a successful address acquisition. This causes 'bursts' of
MAX_CONFLICTS probes followed by a delay of
RATE_LIMIT_INTERVAL instead of a single probe each
RATE_LIMIT_INTERVAL when beyond MAX_CONFLICTS.
The conflict counter should only be cleared after an
address is successfully acquired. This commit achieves that
goal.
From RFC3927:
A host should maintain a counter of the number of address
conflicts it has experienced in the process of trying to
acquire an address, and if the number of conflicts exceeds
MAX_CONFLICTS then the host MUST limit the rate at which it
probes for new addresses to no more than one new address per
RATE_LIMIT_INTERVAL. This is to prevent catastrophic ARP
storms in pathological failure cases, such as a rogue host
that answers all ARP probes, causing legitimate hosts to go
into an infinite loop attempting to select a usable address.
Signed-off-by: Jason Reeder <jasonreeder@gmail.com>
gcc 7 adds -Wimplicit-fallthrough=3 to -Wextra. There are a few ways
we could deal with that. After we take into account the need to stay compatible
with older versions of the compiler (and other compilers), I don't think adding
__attribute__((fallthrough)), even as a macro, is worth the trouble. It sticks
out too much, a comment is just as good. But gcc has some very specific
requiremnts how the comment should look. Adjust it the specific form that it
likes. I don't think the extra stuff we had in those comments was adding much
value.
(Note: the documentation seems to be wrong, and seems to describe a different
pattern from the one that is actually used. I guess either the docs or the code
will have to change before gcc 7 is finalized.)
- linux does not accept prefixes for SLAAC unequal to 64 bits: http://lxr.free-electrons.com/source/net/ipv6/addrconf.c#L2741
- when networkd tries export such a route to the kernel it will get -EINVAL and
set the whole device into a failed state.
- this patch will make networkd ignore such prefixes for SLAAC,
but process other informations which may contain other prefixes.
- Note that rfc4862 does not forbid prefix length != 64 bit
This changes the return value a bit: 1 will be returned if the value is
changed. But the return value was not documented, and the change should
be for the good anyway. Current callers don't care.
This adds in4_addr_is_localhost() and in4_addr_is_link_local() that only take
an IPv4 "struct in_addr", to match in_addr_is_localhost() and
in_addr_is_link_local() that that a "union in_addr_union".
This matches the existing in4_addr_is_null() call that already exists.
For IPv6 glibc already exports a set of macros, hence we don't add similar
functions in6_addr_is_localhost(). We also drop in6_addr_is_null() as
IN6_IS_ADDR_UNSPECIFIED() already provides that.
* networkd: condition_test() can return a negative error, handle that
If a condition check fails with an error we should not consider the check
successful. Fix that.
We should probably also improve logging in this case, but for now, let's just
unbreak this breakage.
Fixes: #3236
* condition: handle unrecognized architectures nicer
When we encounter a check for an architecture we don't know we should not
let the condition check fail with an error code, but instead simply return
false. After all the architecture might just be newer than the ones we know, in
which case it's certainly not our local one.
Fixes: #3236
Apparently newer gcc versions are a bit more forgiving when assigning an
"unsigned char*" pointer to something of a different type. Let's add the
missing cast so that old gcc versions are fine, too.
This reworks sd-ndisc and networkd substantially to support IPv6 RA much more
comprehensively. Since the API is extended quite a bit networkd has been ported
over too, and the patch is not as straight-forward as one could wish. The
rework includes:
- Support for DNSSL, RDNSS and RA routing options in sd-ndisc and networkd. Two
new configuration options have been added to networkd to make this
configurable.
- sd-ndisc now exposes an sd_ndisc_router object that encapsulates a full RA
message, and has direct, friendly acessor functions for the singleton RA
properties, as well as an iterative interface to iterate through known and
unsupported options. The router object may either be retrieved from the wire,
or generated from raw data. In many ways the sd-ndisc API now matches the
sd-lldp API, except that no implicit database of seen data is kept. (Note
that sd-ndisc actually had a half-written, but unused implementaiton of such
a store, which is removed now.)
- sd-ndisc will now collect the reception timestamps of RA, which is useful to
make sd_ndisc_router fully descriptive of what it covers.
Fixes: #1079
It might very well return EAGAIN in case of packet checksum problems and
suchlike, hence let's better handle this nicely, the same way as we do it in
the other sd-network libraries for incoming datagrams.
Let's make sure the inline functions for retrieving TLV data actually carry TLV
in the name, so that we don#t assume they retrieve the whole, raw packet data.
Let's make sd-lldp a bit more like sd-ndisc ant the other APIs, and add proper
ref counting and a separate call for setting the ifindex.
This also adds a new lldp_reset() call we can use at various places to close
all fds. This is also similar to how sd-ndisc already does it.
It's a good idea to store away the recption time of LLDP packets in the
neighbor object, simply because the LLDP data only has a validity of a certain
amount of time.
Hence, let's record the timestamp when we receive the datagram and expose an
API for it. Also, automatically expire LLDP neighbors based on this new
timestamp.
Let's better check the size before we subtract. Also, let's change the size
argument to size_t, as it cannot be signed anyway.
Finally, use EBADMSG for indicating invalid packets, like we do everywhere
else.
Lennart Poettering
AsciiWolf
Alexander Galanin
Jason Reeder
27o
Zbigniew Jędrzejewski-Szmek
Evgeny Vereshchagin
Jörg Thalheim
David Michael
Susant Sahani
Michael Biebl
Thomas Haller
John Paul Adrian Glaubitz