Sometimes it's useful to provide a default value during an environment
expansion, if the environment variable isn't already set.
For instance $XDG_DATA_DIRS is suppose to default to:
/usr/local/share/:/usr/share/
if it's not yet set. That means callers wishing to augment
XDG_DATA_DIRS need to manually add those two values.
This commit changes replace_env to support the following shell
compatible default value syntax:
XDG_DATA_DIRS=/foo:${XDG_DATA_DIRS:-/usr/local/share/:/usr/share}
Likewise, it's useful to provide an alternate value during an
environment expansion, if the environment variable isn't already set.
For instance, $LD_LIBRARY_PATH will inadvertently search the current
working directory if it starts or ends with a colon, so the following
is usually wrong:
LD_LIBRARY_PATH=/foo/lib:${LD_LIBRARY_PATH}
To address that, this changes replace_env to support the following
shell compatible alternate value syntax:
LD_LIBRARY_PATH=/foo/lib${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}}
[zj: gate the new syntax under REPLACE_ENV_ALLOW_EXTENDED switch, so
existing callers are not modified.]
In the future we might want to allow additional syntax (for example
"unset VAR". But let's check that the data we're getting does not contain
anything unexpected.
(Only in environment.d files.)
We have only basic compatibility with shell syntax, but specifying variables
without using braces is probably more common, and I think a lot of people would
be surprised if this didn't work.
merge_env_file is a new function, that's like load_env_file, but takes a
pre-existing environment as an input argument. New environment entries are
merged. Variable expansion is performed.
Falling back to the process environment is supported (when a flag is set).
Alternatively this could be implemented as passing an additional fallback
environment array, but later on we're adding another flag to allow braceless
expansion, and the two flags can be combined in one arg, so there's less
stuff to pass around.
If an environment array has duplicates, strv_env_get_n returns
the results for the first match. This is wrong, because later
entries in the environment are supposed to replace earlier
entries.
strv_env_replace was calling env_match(), which in effect allowed multiple
values for the same key to be inserted into the environment block. That's
pointless, because APIs to access variables only return a single value (the
latest entry), so it's better to keep the block clean, i.e. with just a single
entry for each key.
Add a new helper function that simply tests if the part before '=' is equal in
two strings and use that in strv_env_replace.
In load_env_file_push, use strv_env_replace to immediately replace the previous
assignment with a matching name.
Afaict, none of the callers are materially affected by this change, but it
seems like some pointless work was being done, if the same value was set
multiple times. We'd go through parsing and assigning the value for each
entry. With this change, we handle just the last one.
The output of processes can be gathered, and passed back to the callee.
(This commit just implements the basic functionality and tests.)
After the preparation in previous commits, the change in functionality is
relatively simple. For coding convenience, alarm is prepared *before* any
children are executed, and not before. This shouldn't matter usually, since
just forking of the children should be pretty quick. One could also argue that
this is more correct, because we will also catch the case when (for whatever
reason), forking itself is slow.
Three callback functions and three levels of serialization are used:
- from individual generator processes to the generator forker
- from the forker back to the main process
- deserialization in the main process
v2:
- replace an structure with an indexed array of callbacks
There is a slight change in behaviour: the user manager for root will create a
temporary file in /run/systemd, not /tmp. I don't think this matters, but
simplifies implementation.
Commit 436e916ea introduced the assumption into test-stat-util that /run
is a tmpfs mount point. This is not the case in build chroots such as
Fedora's mock or Debian's sbuild. So only assert that /run is a tmpfs
and not a btrfs if /run is actually a mount point. This will then still
be asserted with installed tests.
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.
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.
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).
Only one test case is added, but it is enough to check basic sanity of the
code (single-line and binary fields and trusted fields, allocation and freeing).
It is useful to package test-* binaries and run them as root under
autopkgtest or manually on particular machines. They currently have a
built-in hardcoded absolute path to their test data, which does not work
when running the test programs from any other path than the original
build directory.
By default, make the tests look for their data in
<test_exe_directory>/testdata/ so that they can be called from any
directory (provided that the corresponding test data is installed
correctly). As we don't have a fixed static path in the build tree (as
build and source tree are independent), set $TEST_DIR with "make check"
to point to <srcdir>/test/, as we previously did with an automake
variable.
ReadOnlyPaths=, ProtectHome=, InaccessiblePaths= and ProtectSystem= are
about restricting access and little more, hence they should be disabled
if PermissionsStartOnly= is used or ExecStart= lines are prefixed with a
"+". Do that.
(Note that we will still create namespaces and stuff, since that's about
a lot more than just permissions. We'll simply disable the effect of
the four options mentioned above, but nothing else mount related.)
This also adds a test for this, to ensure this works as intended.
No documentation updates, as the documentation are already vague enough
to support the new behaviour ("If true, the permission-related execution
options…"). We could clarify this further, but I think we might want to
extend the switches' behaviour a bit more in future, hence leave it at
this for now.
Fixes: #5308
5dd11ab5f3 did a similar change for conf_files_list_strv().
Here we do the same for conf_files_list() and conf_files_list_nulstr().
No change for existing users. Tests are added.
Add a bit of code that tries to get the right parameter order in place
for some of the better known architectures, and skips
restrict_namespaces for other archs.
This also bypasses the test on archs where we don't know the right
order.
In this case I didn't bother with testing the case where no filter is
applied, since that is hopefully just an issue for now, as there's
nothing stopping us from supporting more archs, we just need to know
which order is right.
Fixes: #5241
The compiler warning is a false positive, since n_addresses is always
initialised on the success path from parse_argv(), but the compiler
obviously can’t work that out.
Fixes:
src/test/test-nss.c:426:9: warning: 'n_addresses' may be used uninitialized in this function [-Wmaybe-uninitialized]
On i386 we block the old mmap() call entirely, since we cannot properly
filter it. Thankfully it hasn't been used by glibc since quite some
time.
Fixes: #5240
If a unit foobar@.service stored below /usr is instantiated via a
symlink foobar@quux.service also below /usr, then we should consider the
instance statically enabled, while the template itself should continue
to be considered enabled/disabled/static depending on its [Install]
section.
In order to implement this we'll now look for enablement symlinks in all
unit search paths, not just in the config and runtime dirs.
Fixes: #5136
This is similar to RootDirectory= but mounts the root file system from a
block device or loopback file instead of another directory.
This reuses the image dissector code now used by nspawn and
gpt-auto-discovery.
explicit_bzero was added in glibc 2.25. Make use of it.
explicit_bzero is hardcoded to zero the memory, so string erase now
truncates the string, instead of overwriting it with 'x'. This causes
a visible difference only in the journalctl case.
Gcc7 is smarter about detecting unused functions and detects those two functions
which are unused in tests. But gperf generates them for us, so let's instead of removing
tell gcc that we know they might be unused in the test code.
In file included from ../src/test/test-af-list.c:29:0:
./src/basic/af-from-name.h:140:1: warning: ‘lookup_af’ defined but not used [-Wunused-function]
lookup_af (register const char *str, register size_t len)
^~~~~~~~~
In file included from ../src/test/test-arphrd-list.c:29:0:
./src/basic/arphrd-from-name.h:125:1: warning: ‘lookup_arphrd’ defined but not used [-Wunused-function]
lookup_arphrd (register const char *str, register size_t len)
^~~~~~~~~~~~~
usec_t is always 64bit, which means it can cover quite a number of
years. However, 4 digit year display and glibc limitations around time_t
limit what we can actually parse and format. Let's make this explicit,
so that we never end up formatting dates we can#t parse and vice versa.
Note that this is really just about formatting/parsing. Internal
calculations with times outside of the formattable range are not
affected.
networkd: Allow ':' in label
This reverts a341dfe563 and takes a slightly different approach: anything is
allowed in network interface labels, but network interface names are verified
as before (i.e. amongst other things, no colons are allowed there).
If chase_symlinks() encouters an absolute symlink, it resets the todo
buffer to just the newly discovered symlink and discards any of the
remaining previous symlink path. Regardless of whether or not the
symlink is absolute or relative, we need to preserve the remainder of
the path that has not yet been resolved.
This substantially reworks the seccomp code, to ensure better
compatibility with some architectures, including i386.
So far we relied on libseccomp's internal handling of the multiple
syscall ABIs supported on Linux. This is problematic however, as it does
not define clear semantics if an ABI is not able to support specific
seccomp rules we install.
This rework hence changes a couple of things:
- We no longer use seccomp_rule_add(), but only
seccomp_rule_add_exact(), and fail the installation of a filter if the
architecture doesn't support it.
- We no longer rely on adding multiple syscall architectures to a single filter,
but instead install a separate filter for each syscall architecture
supported. This way, we can install a strict filter for x86-64, while
permitting a less strict filter for i386.
- All high-level filter additions are now moved from execute.c to
seccomp-util.c, so that we can test them independently of the service
execution logic.
- Tests have been added for all types of our seccomp filters.
- SystemCallFilters= and SystemCallArchitectures= are now implemented in
independent filters and installation logic, as they semantically are
very much independent of each other.
Fixes: #4575
