This macro will read a pointer of any type, return it, and set the
pointer to NULL. This is useful as an explicit concept of passing
ownership of a memory area between pointers.
This takes inspiration from Rust:
https://doc.rust-lang.org/std/option/enum.Option.html#method.take
and was suggested by Alan Jenkins (@sourcejedi).
It drops ~160 lines of code from our codebase, which makes me like it.
Also, I think it clarifies passing of ownership, and thus helps
readability a bit (at least for the initiated who know the new macro)
This removes LOG_TARGET_SAFE. It's made redundant by the new
"prohibit-ipc" logging flag, as it used to have a similar effect: avoid
logging to the journal/syslog, i.e. any local services in order to avoid
deadlocks when we lock from PID 1 or its utility processes (such as
generators).
All previous users of LOG_TARGET_SAFE are switched over to the new
setting. This makes things a bit safer for all, as not even the
SYSTEMD_LOG_TARGET env var can be used to accidentally log to the
journal anymore in these programs.
It's a bit weird to test these strings after the fact instead of before.
Let's make sure that we don't even attempt the string escaping if the
strings are NULL.
Follow-up for #7688
Since systemd v236, several Arch users complained that
systemd-cryptsetup-generator exits with an OOM error and that it
prevents the boot from continuing.
Investigating the diff of cryptsetup-generator between v235 and v236 I
noticed that create_disk allowed for the `password` and `filtered`
variables to be NULL (they're handled with `strempty()`) but not their
`*_escaped` versions, and returned OOM errors in those cases.
Fix this by checking that the input string is non-NULL before deciding
that `specifier_escape` had an OOM error.
I could not test this fix myself, but some users have reported success.
Downstream bug: https://bugs.archlinux.org/task/56733
Let's replace usage of fputc_unlocked() and friends by __fsetlocking(f,
FSETLOCKING_BYCALLER). This turns off locking for the entire FILE*,
instead of doing individual per-call decision whether to use normal
calls or _unlocked() calls.
This has various benefits:
1. It's easier to read and easier not to forget
2. It's more comprehensive, as fprintf() and friends are covered too
(as these functions have no _unlocked() counterpart)
3. Philosophically, it's a bit more correct, because it's more a
property of the file handle really whether we ever pass it on to another
thread, not of the operations we then apply to it.
This patch reworks all pieces of codes that so far used fxyz_unlocked()
calls to use __fsetlocking() instead. It also reworks all places that
use open_memstream(), i.e. use stdio FILE* for string manipulations.
Note that this in some way a revert of 4b61c87511.
Let's rename escaped_name to disk_path since this is an actual content
that pointer refers to. It is either path to encrypted block device
or path to encrypted image file.
Also drop redundant function disk_major_minor(). src is always set, and
it always points to either encrypted block device path (or symlink to
such device) or to encrypted image. In case it is set to device path
there is no need to reset it to /dev/block/major:minor symlink since
those paths are equivalent.
Some ask-password agents (e.g. clevis-luks-askpass) use Id option from
/run/systemd/ask-password/ask* file in order to obtain the password for
the device.
Id option should be in the following format,
e.g. Id=subsystem:data. Where data part is supposed to identify object
that ask-password query is done for. Since
e51b9486d1 this field has format
Id=cryptsetup:/dev/block/major:minor when systemd-cryptsetup is
unlocking encrypted block device. However, crypttab also supports
encrypted image files in which case we usually set data part of Id to
"vol on mountpoint". This is unexpected and actually breaks network
based device encryption as implemented by clevis.
Example:
$ cat /etc/crypttab
clevis-unlocked /clevis-test-disk-image none luks,_netdev
$ systemctl start 'systemd-cryptsetup@clevis\x2dunlocked.service'
$ grep Id /run/systemd/ask-password/ask*
Before:
$ Id=cryptsetup:clevis-unlocked on /clevis-test-disk-image-mnt
After:
$ Id=cryptsetup:/clevis-test-disk-image
Also do not include libcryptsetup.h directly, but only through crypt-util.h.
This way we do not have to repeat the define in every file where it is used.
Let's always escape strings we receive from the user before writing them
out to unit file settings that suppor specifier expansion, so that user
strings are transported as-is.
remote-cryptsetup-pre.target was designed as an active unit (that pulls in
network-online.target), the opposite of remote-fs-pre.target (a passive unit,
with individual provider services ordering itself before it and pulling it in,
for example iscsi.service and nfs-client.target).
To make remote-cryptsetup-pre.target really work, those services should be
ordered before it too. But this would require updates to all those services,
not just changes from systemd side.
But the requirements for remote-fs-pre.target and remote-cryptset-pre.target
are fairly similar (e.g. iscsi devices can certainly be used for both), so
let's reuse remote-fs-pre.target also for remote cryptsetup units. This loses
a bit of flexibility, but does away with the requirement for various provider
services to know about remote-cryptsetup-pre.target.
Allow cryptsetup utility to activate LUKS2 devices (with appropriate
libcryptsetup)
The change itself doesn't enforce new libcryptsetup 2.x and is backward
compatible with versions 1.x
We want that cryptsetup can cache keys between multiple invocations, and
it does so via the root user's user keyring, hence let's share it among
services.
Replaces: #6286
When building without veracrypt, gcc warns
../src/cryptsetup/cryptsetup.c:55:13: warning: ‘arg_tcrypt_veracrypt’ defined but not used [-Wunused-variable]
static bool arg_tcrypt_veracrypt = false;
Fix this by conditionalizing the declaration.
This breaks things when the decrypted device is not immediately
`SYSTEMD_READY=1` (e. g. when a multi-device btrfs system is placed on
multiple cryptsetup devices).
Fixes#6537.
As a follow-up for db3f45e2d2 let's do the
same for all other cases where we create a FILE* with local scope and
know that no other threads hence can have access to it.
For most cases this shouldn't change much really, but this should speed
dbus introspection and calender time formatting up a bit.
It seems that there's a common pattern among the various generators. Let's add
a helper function for it and make use of it in cryptsetup-generator.
This fixes a bunch of theoretical memleaks in error paths, since *to wasn't
generally freed properly. Not thath it matters.
This extends 2d79a0bbb9 to the kernel
command line parsing.
The parsing is changed a bit to only understand "0" as infinity. If units are
specified, parse normally, e.g. "0s" is just 0. This makes it possible to
provide a zero timeout if necessary.
Simple test is added.
Fixes https://bugzilla.redhat.com/show_bug.cgi?id=1462378.
If the cryptsetup service unit and swap unit for a swap device
are not strictly ordered, it might happen that the swap unit
activates/mounts the swap device before its cryptsetup service unit
has a chance to run the 'mkswap' command (that it is programmed to).
This leads to the following error:
Starting Cryptography Setup for sda3_crypt...
[ OK ] Found device /dev/mapper/sda3_crypt.
Activating swap /dev/mapper/sda3_crypt...
[ OK ] Activated swap /dev/mapper/sda3_crypt.
[ OK ] Reached target Swap.
[FAILED] Failed to start Cryptography Setup for sda3_crypt.
See 'systemctl status systemd-cryptsetup@sda3_crypt.service' for
details.
[DEPEND] Dependency failed for Encrypted Volumes.
Which happens because the swap device is already mounted:
# systemctl status systemd-cryptsetup@sda3_crypt.service
<...>
Active: failed (Result: exit-code) since Mon 2017-02-27 14:21:43 CST;
54s ago
<...>
<...> systemd[1]: Starting Cryptography Setup for sda3_crypt...
<...> mkswap[2420]: mkswap: error: /dev/mapper/sda3_crypt is mounted;
will not make swapspace
<...>
So, modify cryptsetup-generator to include a 'Before=' option for the
respective 'dev-mapper-%i.swap' device in the cryptsetup service unit.
Now, correct ordering is ensured, and the error no longer occurs:
Starting Cryptography Setup for sda3_crypt...
[ OK ] Found device /dev/mapper/sda3_crypt.
[ OK ] Started Cryptography Setup for sda3_crypt.
Activating swap /dev/mapper/sda3_crypt...
[ OK ] Reached target Encrypted Volumes.
[ OK ] Activated swap /dev/mapper/sda3_crypt.
[ OK ] Reached target Swap.
This improves kernel command line parsing in a number of ways:
a) An kernel option "foo_bar=xyz" is now considered equivalent to
"foo-bar-xyz", i.e. when comparing kernel command line option names "-" and
"_" are now considered equivalent (this only applies to the option names
though, not the option values!). Most of our kernel options used "-" as word
separator in kernel command line options so far, but some used "_". With
this change, which was a source of confusion for users (well, at least of
one user: myself, I just couldn't remember that it's systemd.debug-shell,
not systemd.debug_shell). Considering both as equivalent is inspired how
modern kernel module loading normalizes all kernel module names to use
underscores now too.
b) All options previously using a dash for separating words in kernel command
line options now use an underscore instead, in all documentation and in
code. Since a) has been implemented this should not create any compatibility
problems, but normalizes our documentation and our code.
c) All kernel command line options which take booleans (or are boolean-like)
have been reworked so that "foobar" (without argument) is now equivalent to
"foobar=1" (but not "foobar=0"), thus normalizing the handling of our
boolean arguments. Specifically this means systemd.debug-shell and
systemd_debug_shell=1 are now entirely equivalent.
d) All kernel command line options which take an argument, and where no
argument is specified will now result in a log message. e.g. passing just
"systemd.unit" will no result in a complain that it needs an argument. This
is implemented in the proc_cmdline_missing_value() function.
e) There's now a call proc_cmdline_get_bool() similar to proc_cmdline_get_key()
that parses booleans (following the logic explained in c).
f) The proc_cmdline_parse() call's boolean argument has been replaced by a new
flags argument that takes a common set of bits with proc_cmdline_get_key().
g) All kernel command line APIs now begin with the same "proc_cmdline_" prefix.
h) There are now tests for much of this. Yay!
I think it's an antipattern to have to count the number of bytes in
the prefix by hand. We should do this automatically to avoid wasting
programmer time, and possible errors. I didn't any offsets that were
wrong, so this change is mostly to make future development easier.
This stripping is contolled by a new boolean parameter. When the parameter
is true, it means that the caller does not care about the distinction between
initrd and real root, and wants to act on both rd-dot-prefixed and unprefixed
parameters in the initramfs, and only on the unprefixed parameters in real
root. If the parameter is false, behaviour is the same as before.
Changes by caller:
log.c (systemd.log_*): changed to accept rd-dot-prefix params
pid1: no change, custom logic
cryptsetup-generator: no change, still accepts rd-dot-prefix params
debug-generator: no change, does not accept rd-dot-prefix params
fsck: changed to accept rd-dot-prefix params
fstab-generator: no change, custom logic
gpt-auto-generator: no change, custom logic
hibernate-resume-generator: no change, does not accept rd-dot-prefix params
journald: changed to accept rd-dot-prefix params
modules-load: no change, still accepts rd-dot-prefix params
quote-check: no change, does not accept rd-dot-prefix params
udevd: no change, still accepts rd-dot-prefix params
I added support for "rd." params in the three cases where I think it's
useful: logging, fsck options, journald forwarding options.
It could be that our .service is being stopped precisely because the
device already disappeared (e.g. due to a manual `cryptsetup close`, or
due to UDisks2 cleaning up).
GLIB has recently started to officially support the gcc cleanup
attribute in its public API, hence let's do the same for our APIs.
With this patch we'll define an xyz_unrefp() call for each public
xyz_unref() call, to make it easy to use inside a
__attribute__((cleanup())) expression. Then, all code is ported over to
make use of this.
The new calls are also documented in the man pages, with examples how to
use them (well, I only added docs where the _unref() call itself already
had docs, and the examples, only cover sd_bus_unrefp() and
sd_event_unrefp()).
This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we
tend to call our destructors these days.
Note that this defines no public macro that wraps gcc's attribute and
makes it easier to use. While I think it's our duty in the library to
make our stuff easy to use, I figure it's not our duty to make gcc's own
features easy to use on its own. Most likely, client code which wants to
make use of this should define its own:
#define _cleanup_(function) __attribute__((cleanup(function)))
Or similar, to make the gcc feature easier to use.
Making this logic public has the benefit that we can remove three header
files whose only purpose was to define these functions internally.
See #2008.
Lennart Poettering