This adds a new switch try-empty-password. If set and none of PKCS#11 or
key files work, it is attempted to unlock the volume with an empty
password, before the user is asked for a password.
Usecase: an installer generates an OS image on one system, which is the
booted up for the first time in a possibly different system. The image
is encrypted using a random volume key, but an empty password. A tool
that runs on first boot then queries the user for a password to set or
enrols the volume in the TPM, removing the empty password. (Of course, in
such a scenario it is important to never reuse the installer image on
multiple systems as they all will have the same volume key, but that's a
different question.)
Let's make loading of keys a bit more automatic and define a common
place where key files can be placed. Specifically, whenever a volume of
name "foo" is attempted, search for a key file in
/etc/cryptsetup-keys.d/foo.key and /run/cryptsetup-keys.d/foo.key,
unless a key file is declared explicitly.
With this scheme we have a simple discovery in place that should make it
more straightfoward wher to place keys, and requires no explicit
configuration to be used.
This is useful when the key file is acquired dynamically in some form
and should be erased after use.
Note that this code tries to be robust, and removes the key file both on
success and on failure.
This adds a new crypttab option for volumes "pkcs11-uri=" which takes a
PKCS#11 URI. When used the key stored in the line's key file is
decrypted with the private key the PKCS#11 URI indiciates.
This means any smartcard that can store private RSA keys is usable for
unlocking LUKS devices.
This option is an indication for PID1 that the entry in crypttab is handled by
initrd only and therefore it shouldn't interfer during the usual start-up and
shutdown process.
It should be primarily used with the encrypted device containing the root FS as
we want to keep it (and thus its encrypted device) until the very end of the
shutdown process, i.e. when initrd takes over.
This option is the counterpart of "x-initrd.mount" used in fstab.
Note that the slice containing the cryptsetup services also needs to drop the
usual shutdown dependencies as it's required by the cryptsetup services.
Fixes: #14224
cryptsetup introduced optional locking scheme that should serialize
unlocking keyslots which use memory hard key derivation
function (argon2). Using the serialization should prevent OOM situation
in early boot while unlocking encrypted volumes.
Note that this slightly changes behaviour: "none" is only allowed as
option, if it's the only option specified, but not in combination with
other options. I think this makes more sense, since it's the choice when
no options shall be specified.
libcryptsetup v2.0.1 introduced new API calls, supporting 64 bit wide
integers for `keyfile_offset`. This change invokes the new function
call, gets rid of the warning that was added in #7689, and removes
redundant #ifdefery and constant definitions.
See https://gitlab.com/cryptsetup/cryptsetup/issues/359.
Fixes#7677.
LUKS2 supports so-called tokens. The libcryptsetup internally
support keyring token (it tries to open device using specified
keyring entry).
Only if all token fails (or are not available), it uses a passphrase.
This patch aligns the functionality with the cryptsetup utility
(cryptsetup luksOpen tries tokens first) but does not replace
the systemd native ask-password function (can be used the same in
combination with this patch).
The crypt_load() for LUKS2 can read a quite big area of disk
(metadata area size is configurable and can increase up to megabytes).
This initialization is not needed to be repeated, just use the existing context.
(This patch is also required for the following change.)
If crypt_load() for LUKS succeeds, we know that it is a LUKS device.
Failure of data device setting should fail in this case; remapping
as a PLAIN device late could mean data corruption.
(If a user wants to map PLAIN device over a device with LUKS header,
it should be said explicitly with "plain" argument type.)
Also, if there is no explicit PLAIN type requested and crypt device
is already initialized (crypt_data_type() is set), do not run
the initialization again.
6f177c7dc0 caused key file errors to immediately fail, which would make it hard to correct an issue due to e.g. a crypttab typo or a damaged key file.
Closes#11723.
First of all let's always log where the errors happen, and not in an
upper stackframe, in all cases. Previously we'd do this somethis one way
and sometimes another, which resulted in sometimes duplicate logging and
sometimes none.
When we cannot activate something due to bad password the kernel gives
us EPERM. Let's uniformly return this EAGAIN, so tha the next password
is tried. (previously this was done in most cases but not in all)
When we get EPERM let's also explicitly indicate that this probably
means the password is simply wrong.
Fixes: #11498
Ideally, coccinelle would strip unnecessary braces too. But I do not see any
option in coccinelle for this, so instead, I edited the patch text using
search&replace to remove the braces. Unfortunately this is not fully automatic,
in particular it didn't deal well with if-else-if-else blocks and ifdefs, so
there is an increased likelikehood be some bugs in such spots.
I also removed part of the patch that coccinelle generated for udev, where we
returns -1 for failure. This should be fixed independently.
Instead of
Please enter passphrase for disk <disk-name>!
use
Please enter passphrase for disk <disk-name>:
which is more polite and matches Plymouth convention.
This is a bit like the info link in most of GNU's --help texts, but we
don't do info but man pages, and we make them properly clickable on
terminal supporting that, because awesome.
I think it's generally advisable to link up our (brief) --help texts and
our (more comprehensive) man pages a bit, so this should be an easy and
straight-forward way to do it.
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.
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)
