Following our coding style on success we should initialize all return
parameters of a function. We missed to cases for dns_cache_lookup() (but
covered all others), fix them too.
This is the most important piece of information of replies, hence show
this in the first log message about it.
(Wireshark shows it too in the short summary, hence this definitely
makes sense...)
Retrying a transaction via TCP is a good approach for mitigating
packet loss. However, it's not a good away way to fix a bad RCODE if we
already downgraded to UDP level for it. Hence, don't do this.
This is a small tweak only, but shortens the time we spend on
downgrading when a specific domain continously returns a bad rcode.
Some domains (such as us.ynuf.alipay.com) almost appear as if they actively
want to sabotage our DNSSEC work. Specifically, they unconditionally
return SERVFAIL on SOA lookups and always only after a 1s delay (at
least). This is pretty bad for our validation logic, as we use SOA
lookups to distuingish zones from non-terminal names. Moreover, SERVFAIL
is an error that is typically returned if we send requests a server
doesn't grok, and thus is reason for us to downgrade our protocol and
try again. In case of these zones this means we'll accept the SERVFAIL
response only after a full iterative downgrade to our lowest feature
level: TCP. In combination with the 1s delays this has the effect of
making us hit our transaction timeout way to easily.
As first attempt to improve the situation: let's start caching SERVFAIL
responses in our cache, after the full downgrade for a short period of
time.
Conceptually this is exposed as "weird rcode" caching, but for now we
only consider SERVFAIL a "weird rcode" worthy of caching. Later on we
might want to add more.
When we are doing a TCP transaction the kernel will automatically resend
all packets for us, there's no need to do that ourselves. Hence:
increase the timeout for TCP transactions substantially, to give the
kernel enough time to connect to the peer, without interrupting it when
we become impatient.
Let's make sure that if we accept a query candidate, then let's also
propagate the authenticated flag for it, so that we can properly report
back to the clients whether lookups failed due to non-existance that can
be proven.
The cache might contain all kinds of unauthenticated data that we really
shouldn't be using if we upgrade our feature level and suddenly are able
to get authenticated data again.
Might fix: #4866
For the wildcard NSEC check we need to generate an "asterisk" domain, by
prepend the common ancestor with "*.". So far we did that with a simple
strappenda() which is fine for most domains, but doesn't work if the
common ancestor is the root domain as we usually write that as "." in
normalized form, and "*." joined with "." is "*.." and not "*." as it
should be.
Hence, use the clean way out, let's just use dns_name_concat() which
only exists precisely for this reason, to properly concatenate labels.
There's a good chance this actually fixes#5029, as this NSEC proof is
triggered by lookups in the TLD "example", which doesn't exist in the
Internet.
This ensures that configured NTAs exclude not only the listed domain but
also all domains below it from DNSSEC validation -- except if a positive
trust anchor is defined below (as suggested by RFC7647, section 1.1)
Fixes: #5048
As the kernel won't map the UIDs this is simply not safe, and hence we
should generate a clean error and refuse it.
We can restore this feature later should a "shiftfs" become available in
the kernel.
This changes the file copy logic of machined to set the UID/GID of all
copied files to 0 if the host and container do not share the same user
namespace.
Fixes: #4078
This adds a unified "copy_flags" parameter to all copy_xyz() function
calls, replacing the various boolean flags so far used. This should make
many invocations more readable as it is clear what behaviour is
precisely requested. This also prepares ground for adding support for
more modes later on.
With this change we'll not show an "Addresses" field for machines that
we don't know any addresses for.
This changes print_addresses() to never suffix its output with a
newline, leaving that to the caller. That's a good idea since depending
on who the caller is, different rules apply: if no addresses are found,
then the list view still wants a newline, but the status view does not.
This also changes the function to return the number of found addresses,
which can be used to decide when to add a newline or not.
UID/GID mapping with userns can be arbitrarily complex. Let's break this
down to a single admin-friendly parameter: let's expose the UID/GID
shift of a container via a new bus call for each container, and let's
show this as part of "machinectl status" if it is not 0.
This should work for pretty much all real-life full OS container setups
(i.e. the stuff machined is suppose to be useful for). For everything
else we generate a clean error, clarifying that we can't expose the
mapping.
This changes resolved to use the compile-time fallback hostname the
configured one is not set. Note that if the local hostname is set to
"localhost" then we'll instead default to "linux" here, as for
mDNS/LLMNR exposing "localhost" is actively dangerous.
Currently, if the hostname is not set gethostname_malloc() defaults to
the "sysname", which is "linux" on Linux. Let's change that to also
honour the compile-time fallback hostname as specified on the configure
command line.
Drop the TEST_DATA_DIR macro as this was using alloca() within a
function call which is allegedly unsafe. So add a "suffix" argument to
get_testdata_dir() instead and call that directly.
Rename get_exe_relative_testdata_dir() to get_testdata_dir() and move
the env var check into that, so that everything interesting happens at
the same place.
automake helpfully sets a few variables for during build. When our executable
is in a directory underneath $(abs_top_builddir), we know that we're in the
build environment $(abs_top_srcdir) contains the sources, and test data is
under $(abs_top_srcdir)/test. This remains true no matter where the build
directory is relative to the source directory. It also works if the test
executable is invoked as ./test-whatever or .libs/test-whatever, since the
relative path is not used at all.
When running from outside of the build directory, we should be running from the
installed location and we can look for ../testdata relative to the location of
the exe file.
Of course, $SYSTEMD_TEST_DATA always overrides this logic.
That way, if the test directory does not exist we don't leave behind
temporary files (as in that case or on test failure the cleanup actions
don't run).
When trying to directly run a test executable in the build tree without
setting $TEST_DIR, some tests fail with a non-obvious error message.
Print an useful one instead.
This is a follow-up for #5359, fixing the error codes in a similar way
for the other NSS modules.
(user/group lookup calls don't have h_errnop, hence we don't update that
in those cases)
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>
The correct error code to report when a provided buffer is too small is
ERANGE. This is recognized by glibc, which will then try again with a
larger buffer. The old behaviour of reporting ENOMEM has no special
meaning for glibc. The error will simply be propagated to the
application, and a later retry will trigger the same error again.
Additionally, h_errnop must be set to NETDB_INTERNAL to have glibc look
at errnop for details.
More information at:
https://www.gnu.org/software/libc/manual/html_node/NSS-Modules-Interface.html
Now we track the sections for example [Address] via line number.
Which was fine till we din't had dropins dir. If we have multiple
sections which have the ideantical line number in diffrent files
we are overwriting these since line number is the key.
This patch fixes this by taking filename and line number as key.
This fixes [Address] and [Route] section overwriting.
fixes: #5141
This breaks again, this time for setups where Qemu is not reported via DMI for whatever
reason. So swap order of cpuid and dmi again, but properly detect oracle.
See issue #5318.
$ ./coredumpctl --no-pager -1
TIME PID UID GID SIG COREFILE EXE
Sun 2016-11-06 10:10:51 EST 29514 1002 1002 - - /usr/bin/python3.5
$ ./coredumpctl info 29514
PID: 29514 (python3)
UID: 1002 (zbyszek)
GID: 1002 (zbyszek)
Reason: ZeroDivisionError
Timestamp: Sun 2016-11-06 10:10:51 EST (3h 22min ago)
Command Line: python3 systemd_coredump_exception_handler.py
Executable: /usr/bin/python3.5
Control Group: /user.slice/user-1002.slice/user@1002.service/gnome-terminal-server.service
Unit: user@1002.service
User Unit: gnome-terminal-server.service
Slice: user-1002.slice
Owner UID: 1002 (zbyszek)
Boot ID: 1531fd22ec84429e85ae888b12fadb91
Machine ID: 519a16632fbd4c71966ce9305b360c9c
Hostname: laptop
Storage: none
Message: Process 29514 (systemd_coredump_exception_handler.py) of user zbyszek failed with ZeroDivisionError: division by
Traceback (most recent call last):
File "systemd_coredump_exception_handler.py", line 134, in <module>
g()
File "systemd_coredump_exception_handler.py", line 133, in g
f()
File "systemd_coredump_exception_handler.py", line 131, in f
div0 = 1 / 0
ZeroDivisionError: division by zero
Local variables in innermost frame:
a=3
h=<function f at 0x7efdc14b6ea0>
Embedding sd_id128_t's in constant strings was rather cumbersome. We had
SD_ID128_CONST_STR which returned a const char[], but it had two problems:
- it wasn't possible to statically concatanate this array with a normal string
- gcc wasn't really able to optimize this, and generated code to perform the
"conversion" at runtime.
Because of this, even our own code in coredumpctl wasn't using
SD_ID128_CONST_STR.
Add a new macro to generate a constant string: SD_ID128_MAKE_STR.
It is not as elegant as SD_ID128_CONST_STR, because it requires a repetition
of the numbers, but in practice it is more convenient to use, and allows gcc
to generate smarter code:
$ size .libs/systemd{,-logind,-journald}{.old,}
text data bss dec hex filename
1265204 149564 4808 1419576 15a938 .libs/systemd.old
1260268 149564 4808 1414640 1595f0 .libs/systemd
246805 13852 209 260866 3fb02 .libs/systemd-logind.old
240973 13852 209 255034 3e43a .libs/systemd-logind
146839 4984 34 151857 25131 .libs/systemd-journald.old
146391 4984 34 151409 24f71 .libs/systemd-journald
It is also much easier to check if a certain binary uses a certain MESSAGE_ID:
$ strings .libs/systemd.old|grep MESSAGE_ID
MESSAGE_ID=%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x
MESSAGE_ID=%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x
MESSAGE_ID=%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x
MESSAGE_ID=%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x
$ strings .libs/systemd|grep MESSAGE_ID
MESSAGE_ID=c7a787079b354eaaa9e77b371893cd27
MESSAGE_ID=b07a249cd024414a82dd00cd181378ff
MESSAGE_ID=641257651c1b4ec9a8624d7a40a9e1e7
MESSAGE_ID=de5b426a63be47a7b6ac3eaac82e2f6f
MESSAGE_ID=d34d037fff1847e6ae669a370e694725
MESSAGE_ID=7d4958e842da4a758f6c1cdc7b36dcc5
MESSAGE_ID=1dee0369c7fc4736b7099b38ecb46ee7
MESSAGE_ID=39f53479d3a045ac8e11786248231fbf
MESSAGE_ID=be02cf6855d2428ba40df7e9d022f03d
MESSAGE_ID=7b05ebc668384222baa8881179cfda54
MESSAGE_ID=9d1aaa27d60140bd96365438aad20286
Lennart Poettering
Evgeny Vereshchagin
Keith Busch
Benjamin Robin
Zbigniew Jędrzejewski-Szmek
Martin Pitt
Michael Biebl
Martin Pitt
Jason Reeder
Maarten de Vries
Susant Sahani
Christian Hesse