We always need to make them unions with a "struct cmsghdr" in them, so
that things properly aligned. Otherwise we might end up at an unaligned
address and the counting goes all wrong, possibly making the kernel
refuse our buffers.
Also, let's make sure we initialize the control buffers to zero when
sending, but leave them uninitialized when reading.
Both the alignment and the initialization thing is mentioned in the
cmsg(3) man page.
It fully initializes the address structure, so no need for pre-initialization,
and also returns the length of the address, so no need to recalculate using
SOCKADDR_UN_LEN().
socklen_t is unsigned, so let's not use an int for it. (It doesn't matter, but
seems cleaner and more portable to not assume anything about the type.)
.msg_namelen was set to a bogus value before we actually stored the path in the
the structure. sockaddr_un_set_path() returns the length, so just use that.
Fixes#14799.
If we do, we operate on a separate set of logs and runtime objects
The namespace is configured via argv[1].
Fixes: #12123Fixes: #10230#9519
(These latter two issues ask for slightly different stuff, but the
usecases generally can be solved by running separate instances of
journald now, hence also declaring that as "Fixes:")
All over the place we define local variables for the various sockopts
that take a bool-like "int" value. Sometimes they are const, sometimes
static, sometimes both, sometimes neither.
Let's clean this up, introduce a common const variable "const_int_one"
(as well as one matching "const_int_zero") and use it everywhere, all
acorss the codebase.
This is useful if someone wants to recreate the original syslog datagram. We
already include timestamp information as _SOURCE_REALTIME_TIMESTAMP=, and in
normal use that timestamp, converted back to the form used by syslog
(Mth dd HH:MM:SS) would usually give the value. But there are various
circumstances where this might not be true. Most obviously, if the datagram is
sent a bit later after being prepared, the time is rounded to the nearest
second, and it might be off. This is especially bad around New Year when the
syslog timestamp wraps around. Then the same timezone and locale need to be
used to recreate the original timestamp. In the end doing this reliably is
complicated, and it seems much easier to just unconditionally include the
original timestamp.
If the original timestamp cannot be located, we store the full log line.
This way, it should be always possible to recreate the original input.
Example:
MESSAGE=x
SYSLOG_TIMESTAMP=Sep 15 15:07:58
SYSLOG_RAW
^]^@^@^@^@^@^@^@<13>Sep 15 15:07:58 HOST: x^@y
_PID=3318
_SOURCE_REALTIME_TIMESTAMP=1530743976393553
Fixes#2398.
These lines are generally out-of-date, incomplete and unnecessary. With
SPDX and git repository much more accurate and fine grained information
about licensing and authorship is available, hence let's drop the
per-file copyright notice. Of course, removing copyright lines of others
is problematic, hence this commit only removes my own lines and leaves
all others untouched. It might be nicer if sooner or later those could
go away too, making git the only and accurate source of authorship
information.
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
And let's make use of it to implement two new unit settings with it:
1. LogLevelMax= is a new per-unit setting that may be used to configure
log priority filtering: set it to LogLevelMax=notice and only
messages of level "notice" and lower (i.e. more important) will be
processed, all others are dropped.
2. LogExtraFields= is a new per-unit setting for configuring per-unit
journal fields, that are implicitly included in every log record
generated by the unit's processes. It takes field/value pairs in the
form of FOO=BAR.
Also, related to this, one exisiting unit setting is ported to this new
facility:
3. The invocation ID is now pulled from /run/systemd/units/ instead of
cgroupfs xattrs. This substantially relaxes requirements of systemd
on the kernel version and the privileges it runs with (specifically,
cgroupfs xattrs are not available in containers, since they are
stored in kernel memory, and hence are unsafe to permit to lesser
privileged code).
/run/systemd/units/ is a new directory, which contains a number of files
and symlinks encoding the above information. PID 1 creates and manages
these files, and journald reads them from there.
Note that this is supposed to be a direct path between PID 1 and the
journal only, due to the special runtime environment the journal runs
in. Normally, today we shouldn't introduce new interfaces that (mis-)use
a file system as IPC framework, and instead just an IPC system, but this
is very hard to do between the journal and PID 1, as long as the IPC
system is a subject PID 1 manages, and itself a client to the journal.
This patch cleans up a couple of types used in journal code:
specifically we switch to size_t for a couple of memory-sizing values,
as size_t is the right choice for everything that is memory.
Fixes: #4089Fixes: #3041Fixes: #4441
When we drop messages of a unit, we log about. Let's add some structured
data to that. Let's include how many messages we dropped, but more
importantly, let's link up the message we generate to the unit we
dropped the messages from by using the "OBJECT" logic, i.e. by
generating OBJECT_SYSTEMD_UNIT= fields and suchlike, that "journalctl
-u" and friends already look for.
Fixes: #6494
The advantage is that is the name is mispellt, cpp will warn us.
$ git grep -Ee "conf.set\('(HAVE|ENABLE)_" -l|xargs sed -r -i "s/conf.set\('(HAVE|ENABLE)_/conf.set10('\1_/"
$ git grep -Ee '#ifn?def (HAVE|ENABLE)' -l|xargs sed -r -i 's/#ifdef (HAVE|ENABLE)/#if \1/; s/#ifndef (HAVE|ENABLE)/#if ! \1/;'
$ git grep -Ee 'if.*defined\(HAVE' -l|xargs sed -i -r 's/defined\((HAVE_[A-Z0-9_]*)\)/\1/g'
$ git grep -Ee 'if.*defined\(ENABLE' -l|xargs sed -i -r 's/defined\((ENABLE_[A-Z0-9_]*)\)/\1/g'
+ manual changes to meson.build
squash! build-sys: use #if Y instead of #ifdef Y everywhere
v2:
- fix incorrect setting of HAVE_LIBIDN2
This adds IOVEC_INIT() and IOVEC_MAKE() for initializing iovec structures
from a pointer and a size. On top of these IOVEC_INIT_STRING() and
IOVEC_MAKE_STRING() are added which take a string and automatically
determine the size of the string using strlen().
This patch removes the old IOVEC_SET_STRING() macro, given that
IOVEC_MAKE_STRING() is now useful for similar purposes. Note that the
old IOVEC_SET_STRING() invocations were two characters shorter than the
new ones using IOVEC_MAKE_STRING(), but I think the new syntax is more
readable and more generic as it simply resolves to a C99 literal
structure initialization. Moreover, we can use very similar syntax now
for initializing strings and pointer+size iovec entries. We canalso use
the new macros to initialize function parameters on-the-fly or array
definitions. And given that we shouldn't have so many ways to do the
same stuff, let's just settle on the new macros.
(This also converts some code to use _cleanup_ where dynamically
allocated strings were using IOVEC_SET_STRING() before, to modernize
things a bit)
Cache client metadata, in order to be improve runtime behaviour under
pressure.
This is inspired by @vcaputo's work, specifically:
https://github.com/systemd/systemd/pull/2280
That code implements related but different semantics.
For a longer explanation what this change implements please have a look
at the long source comment this patch adds to journald-context.c.
After this commit:
# time bash -c 'dd bs=$((1024*1024)) count=$((1*1024)) if=/dev/urandom | systemd-cat'
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 11.2783 s, 95.2 MB/s
real 0m11.283s
user 0m0.007s
sys 0m6.216s
Before this commit:
# time bash -c 'dd bs=$((1024*1024)) count=$((1*1024)) if=/dev/urandom | systemd-cat'
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB, 1.0 GiB) copied, 52.0788 s, 20.6 MB/s
real 0m52.099s
user 0m0.014s
sys 0m7.170s
As side effect, this corrects the journal's rate limiter feature: we now
always use the unit name as key for the ratelimiter.
This moves pretty much all uses of getpid() over to getpid_raw(). I
didn't specifically check whether the optimization is worth it for each
replacement, but in order to keep things simple and systematic I
switched over everything at once.
This reverts commit 6355e75610.
The previously mentioned commit inadvertently broke a lot of SELinux related
functionality for both unprivileged users and systemd instances running as
MANAGER_USER. In particular, setting the correct SELinux context after a User=
directive is used would fail to work since we attempt to set the security
context after changing UID. Additionally, it causes activated socket units to
be mislabeled for systemd --user processes since setsockcreatecon() would never
be called.
Reverting this fixes the issues with labeling outlined above, and reinstates
SELinux access checks on unprivileged user services.
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
We don't have plural in the name of any other -util files and this
inconsistency trips me up every time I try to type this file name
from memory. "formats-util" is even hard to pronounce.
The macro determines the right length of a AF_UNIX "struct sockaddr_un" to pass to
connect() or bind(). It automatically figures out if the socket refers to an
abstract namespace socket, or a socket in the file system, and properly handles
the full length of the path field.
This macro is not only safer, but also simpler to use, than the usual
offsetof() + strlen() logic.
The code to format the iovec is shared with log.c. All call sites to
server_driver_message are changed to include the additional "MESSAGE="
part, but the new functionality is not used and change in functionality
is not expected.
iovec is preallocated, so the maximum number of messages is limited.
In server_driver_message N_IOVEC_PAYLOAD_FIELDS is currently set to 1.
New code is not oom safe, it will fail if memory cannot be allocated.
This will be fixed in subsequent commit.
function.
Not sure if this results in an exploitable buffer overflow, probably not
since the the int value is likely sanitized somewhere earlier and it's
being put through a bit mask shortly before being used.
The stream event source has a priority of SD_EVENT_PRIORITY_NORMAL+5,
and stdout source +10, but the native and syslog event sources are left
at the default of 0.
As a result, any heavy native or syslog logger can cause starvation of
the other loggers. This is trivially demonstrated by running:
dd if=/dev/urandom bs=8k | od | systemd-cat & # native spammer
systemd-run echo hello & # stream logger
journalctl --follow --output=verbose --no-pager --identifier=echo &
... and wait, and wait, the "hello" never comes.
Now kill %1, "hello" arrives finally.
Let's distuingish the cases where our code takes an active role in
selinux management, or just passively reports whatever selinux
properties are set.
mac_selinux_have() now checks whether selinux is around for the passive
stuff, and mac_selinux_use() for the active stuff. The latter checks the
former, plus also checks UID == 0, under the assumption that only when
we run priviliged selinux management really makes sense.
Fixes: #1941