In sd-device, `devpath` is a kind of syspath without '/sys' prefix, e.g.
/devices/pci0000:00/0000:00:1c.4/0000:3c:00.0/nvme/nvme0/nvme0n1,
and `devname` is a path to the device node, e.g. /dev/nvme0n1.
Let's use the consistent name for the helper function.
Let's rework how we lock loopback block devices in two ways:
1. Lock a separate fd, instead of the main block device fd. We already
did that for our internal locking when allocating loopback block
devices, but do so for the exposed locking (i.e.
loop_device_flock()), too, so that the lock is independent of the
main fd we actually use of IO.
2. Instead of locking the device during allocation of the loopback
device, then unlocking it (which will make udev run), and then
re-locking things if we need, let's instead just keep the lock the
whole time, to make things a bit safer and faster, and not have to
wait for udev at all. This is done by adding a "lock_op" parameter to
loop device allocation functions that declares the initial state of
the lock, and is one of LOCK_UN/LOCK_SH/LOCK_EX. This change also
shortens a lot of code, since we allocate + immediately lock loopback
devices pretty much everywhere.
systemd-growfs currently requires that udev ran first to work (because
/dev/block/ symlinks must exist) but that is not what happens when
we're not using initrd and systemd is PID1.
Add a new tpm2_parse_pcr_argument() helper that unifies how we merge PCR
masks in a single function, we can use all over the place. Previously we
had basically the same code for this at 4 places.
Let's lock the backing fd instead of locking/unlocking multiple
times when doing multiple operations with repart. It doesn't make
much sense for anything else to touch the block device while there
are still repart operations pending on it. By keeping the lock over
the full duration of repart, we avoid anything else from interfering
with the block device inbetween operations.
Via the "backing_fd" variable we intend to pin the backing inode through
our entire code. So far we typically created the fd via F_DUPFD_CLOEXEC,
and thus any BSD lock taken one the original fd is shared with our
backing_fd reference. And if the origina fd is closed but our backing_fd
is not, we'll keep the BSD lock open, even if we then reopen the block
device through the backing_fd. If hit, this results in a deadlock.
Let's fix that by creating the backing_fd via fd_reopen(), so that the
locks are no longer shared, and if the original fd is closed all BSD
locks on it that are in effect are auto-released.
(Note the deadlock is only triggered if multiple operations on the same
backing inode are executed, i.e. factory reset, resize and applying of
partitions.)
Replaces: #24181
This allows growfs to expand the filesystem even when the underlying
block device cannot be expanded. This has been useful for example on
LUKS devices that have already been expanded using systemd-repart.
This works around the following error:
```
root@mobian:/home/mobian# /usr/lib/systemd/systemd-growfs /
crypt_resize() of /dev/block/179:2 failed: Operation not permitted
```
This causes systemd-growfs to exit before resizing the partition when
`--dry-run` is passed. Resizing during a dry run of a change breaks the
users expectations.
This is a simple safety check, since we shouldn't invoke ioctls on fds
without being reasonably sure they are of the right type since ioctls
are overloaded, and we might be tricked hence to execute an operation on
an fd which means something different than what we expect.
We currently have a convoluted and complex selection of which random
numbers to use. We can simplify this down to two functions that cover
all of our use cases:
1) Randomness for crypto: this one needs to wait until the RNG is
initialized. So it uses getrandom(0). If that's not available, it
polls on /dev/random, and then reads from /dev/urandom. This function
returns whether or not it was successful, as before.
2) Randomness for other things: this one uses getrandom(GRND_INSECURE).
If it's not available it uses getrandom(GRND_NONBLOCK). And if that
would block, then it falls back to /dev/urandom. And if /dev/urandom
isn't available, it uses the fallback code. It never fails and
doesn't return a value.
These two cases match all the uses of randomness inside of systemd.
I would prefer to make both of these return void, and get rid of the
fallback code, and simply assert in the incredibly unlikely case that
/dev/urandom doesn't exist. But Luca disagrees, so this commit attempts
to instead keep case (1) returning a return value, which all the callers
already check, and fix the fallback code in (2) to be less bad than
before.
For the less bad fallback code for (2), we now use auxval and some
timestamps, together with various counters representing the invocation,
hash it all together and provide the output. Provided that AT_RANDOM is
secure, this construction is probably okay too, though notably it
doesn't have any forward secrecy. Fortunately, it's only used by
random_bytes() and not by crypto_random_bytes().
No actual code changes, just splitting out of some dev_t handling
related calls from stat-util.[ch], they are quite a number already, and
deserve their own module now I think.
Also, try to settle on the name "devnum" as the name for the concept,
instead of "devno" or "dev" or "devid". "devnum" is the name exported in
udev APIs, hence probably best to stick to that. (this just renames a
few symbols to "devum", local variables are left untouched, to make the
patch not too invasive)
No actual code changes.
This is a high-level function, and it belongs in libsystemd-shared. This way we
don't end up linking a separate copy into various binaries. It would even end
up in libsystemd, where it is not needed. (Maybe it'd be removed in some
optimization phase, but it's better to not rely on that.)
$ grep -l -r -a 'path is not absolute%s' build/
build/libnss_systemd.so.2
build/pam_systemd_home.so
build/test-dlopen
build/src/basic/libbasic.a.p/path-util.c.o
build/src/basic/libbasic.a
build/src/shared/libsystemd-shared-249.so
build/test-bus-error
build/libnss_mymachines.so.2
build/pam_systemd.so
build/libnss_resolve.so.2
build/libnss_myhostname.so.2
build/libsystemd.so.0.32.0
build/libudev.so.1.7.2
$ grep -l -r -a 'path is not absolute%s' build/
build/src/shared/libsystemd-shared-251.a.p/parse-helpers.c.o
build/src/shared/libsystemd-shared-251.a
build/src/shared/libsystemd-shared-251.so
No functional change.
Same idea as 03677889f0.
No functional change intended. The type of the iterator is generally changed to
be 'const char*' instead of 'char*'. Despite the type commonly used, modifying
the string was not allowed.
I adjusted the naming of some short variables for clarity and reduced the scope
of some variable declarations in code that was being touched anyway.
Add support for PIN enrollment with TPM2. A new "tpm2-pin" field is
introduced into metadata to signal that the policy needs to include a
PIN.
v2: fix tpm2_make_luks2_json in sd-repart
Modify TPM2 authentication policy to optionally include an authValue, i.e.
a password/PIN. We use the "PIN" terminology since it's used by other
systems such as Windows, even though the PIN is not necessarily numeric.
The pin is hashed via SHA256 to allow for arbitrary length PINs.
v2: fix tpm2_seal in sd-repart
v3: applied review feedback
The approach to use '''…'''.split() instead of a list of strings was initially
used when converting from automake because it allowed identical blocks of lines
to be used for both, making the conversion easier.
But over the years we have been using normal lists more and more, especially
when there were just a few filenames listed. This converts the rest.
No functional change.
We expose various other forms of UUID helpers already, i.e.
SD_ID128_UUID_FORMAT_STR and SD_ID128_MAKE_UUID_STR(), and we parse
UUIDs, hence add a high-level helper for formatting UUIDs too.
This doesn't add any new code, it just moves some helpers
id128-util.[ch] → sd-id128.[ch], to make them public.
This queries the sector size from libfdisk instead of assuming 512, and
uses that when converting from bytes to the offset/size values libfdisk
expects.
This is an alternative to Tom Yan's #21823, but prefers using libfdisk's
own ideas of the sector size instead of going directly to the backing
device via ioctls. (libfdisk can after all also operate on regular
files, where the sector size concept doesn't necessarily apply the same
way.)
This also makes the "grain" variable, i.e. how we'll align the
partitions. Previously this was hardcoded to 4K, and that still will be
the minimum grain we use, but should the sector size be larger than that
we'll use the next multiple of the sector size instead.
This reduces dependencies. The speed of the code here is uimportant, because we
hash only a tiny amount of input data.
Debian and Ubuntu currently build without repart, see
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=976959
> repart requires openssl and so far I tried to avoid linking against
> both gnutls and openssl.
Co-authored-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>