Replace ioutil.WriteFile with os.WriteFile since the former has been
deprecated since go1.16 and simply calls the latter.
Signed-off-by: Miguel Pires <miguel.pires@canonical.com>
This commit adds support for the UC20 LittleKernel bootloader to snapd.
The big changes for using V2 are that we now use a secure bootloader set kernel
command line parameter to identify what disk to look for bootloader environment
structures, and that we use different lkenv structs for different role
bootloaders.
Eventually we should make V1 also use a secure bootloader set kernel command
line parameter to identify what disk to look for bootloader environment
structures on too, as using the partition label like this is vulnerable to
attack by attaching a USB disk with the same partition label to the system.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk{,env}: use xerrors to make Load() err observable as ErrNotExist
Previously we would never continue in SetBootVars if the file doesn't exist
because we used fmt.Errorf which does not preserve the error type such that
os.IsNotExist would return true.
Now, we can continue to provide a customized error message from Load(), as well
as make SetBootVars continue and just write out a new file even if we can't read
the lkenv file in Load().
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* many: rename disks.FindMatching... to FindMatching...WithFsLabel and err types
This is to accommodate a future FindMatching...WithPartLabel. Additionally, an
internal refactor to support storing additional properties for partitions when
we search a disk is implemented to allow for the additional future method.
The error type now is also more versatile to allow specifying what part failed,
searching for a partition by filesystem label or by partition label.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks: add FindMatchingPartitionUUIDFromPartLabel to Disk iface
This will enable searching for a partition with a given label on the provided
disk.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: search for partition labels on the bootloader disk, not fs labels
The partitions with the bootloader structures we care about do not have
filesystems on them, and as such they will not have filesystem labels. Instead,
they will have partition labels, and as such we should search using the
partition label instead.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: rename inRuntimeMode to prepareImageTime
This simplifies numerous functions to be more clear with the simpler
prepare-image time implementation happening first, then the complex runtime
cases happening afterwards are not indented as much.
Thanks to @bboozzoo for the suggestion.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: rename var
Thanks to @bboozzoo for the suggestion.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: fix handling of os.ErrNotExist everywhere, add comments
We should be using xerrors.Is() everywhere here, since the error returned is
wrapped.
However, for specifically RemoveKernelAssets, it's not a bug that we would skip
over os.ErrNotExist, but it would result in a more confusing error message - we
should try to give better error messages, and returning early with
os.ErrNotExist is more useful to the user than the existing error around not
being able to find the specified kernel blob.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: move prepare-image check earlier in ExtractRecoveryKernelAssets
Thanks to @bboozzoo for the recommendation.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks/disks_linux.go: adjust comment about optional partition labels
Thanks to @bboozzoo for clarifying this for me. Partition labels are optional on
GPT partitions.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks/disks.go: fix typo
Thanks to @bboozzoo for catching this.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks/disks_linux.go: add some TODOs about things to cleanup/simplify
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks/disks_linux.go: add comments about the encoding of the udev props
Thanks to @bboozzoo for the suggestion.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks/mockdisk.go: fix typo
Thanks to @bboozzoo again for spotting all my typos :-)
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* osutil/disks: add FindMatchingPartitionUUIDFromPartLabel to Disk iface
This will enable searching for a partition with a given label on the provided
disk.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* many: fix rename of disks pkg function name from rebase
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: don't use l.rootdir for the returned partition file
Using l.rootdir here was wrong in that it would produce for RoleRunMode
bootloaders paths like /run/mnt/ubuntu-boot/dev/disk/by-partuuid/1234, instead
of the correct path of /dev/disk/by-partuuid/... at runtime.
We didn't catch this in tests because we pass in the same rootdir as what we
test for, we didn't test passing in boot.InitramfsUbuntuBootDir for example, so
change the tests to account for this.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lkenv: add compatibility error impl for Go 1.9
Go 1.9 os.PathError does not implement Unwrap(), so using
xerrors.Is(err,os.ErrNotExist) does not work, as Is() calls Unwrap() in a loop,
waiting for either the error returned to be equal to the target error or to be
nil, and in the case of Go 1.9, where os.PathError does not implement Unwrap(),
then nil is returned and Is() returns false.
We can work around this by implementing Unwrap() on our own error type and
specifically returning os.ErrNotExist on Go 1.9 when we know the error is
actually os.ErrNotExist.
This will make the unit tests with Go 1.9 pass.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: use specific backup file for lkenv
For UC20 runtime, the backup file will be a different partition, and since we
are using partition uuid symlinks instead of partition labels, we can't just
append "bak" to the primary env file, and instead need to manually provide the
backup file.
Also add a test which validates that the backup env file for run mode on uc20 is
handled appropriately and updated.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: add test scaffolding and TODO about recovery system add/remove
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: adjust comments
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lkenv/lkenv.go: change XXX to TODO
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lkenv/lkenv.go: inspect the err in compatErrNotExist for Unwrap()
Instead of checking the version of Go we were compiled with which is weird, we
can instead just check for the exact thing we know doesn't work, which is that
os.PathError doesn't implement Unwrap(), so if it doesn't implement Unwrap(), we
know we are in a legacy version of Go and thus should do the manual unwrapping
to return ErrNotExist directly.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: refactor helper methods
This refactors some helper methods to be more clear, namely that envFile becomes
envBackstore, and it takes an argument for whether or not it is returning the
primary or the backup, and eliminating the specific method for getting the
backup file, as well as combining some codepaths in the other helpers to be more
easily readable if slightly redundant in terms of actual code execution.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: move some function definitions around for conventions' sake
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: adjust comment to explain we should try to use kernel cmdline
It might not be there on older gadget bootloaders which don't set that kernel
command line value and as such we will have to fallback to our current behavior.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lkenv/lkenv.go: fix for gofmt 1.9
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk: update handling of os.ErrNotExist for various cases
The only case where we can really proceed without having an initial env file is
at prepare image time when the bootloader env file doesn't exist, as we could be
writing an empty/new one. All other cases we need the file to exist as a
pre-requisite, if only for accurate error reporting.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: rename variable, simplify return statement
Thanks to @pedronis for the suggestion.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: implement TODO about checking the backup file in Present()
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk.go: re-word awkwardly phrased TODO about using kernel cmdline
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
* bootloader/lk_test.go: add unit test for Present() RoleSole checking backup
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
Co-authored-by: Maciej Borzecki <maciej.zenon.borzecki@canonical.com>
This is simpler and avoids from having to maintain the list of names of
bootloaders in three locations, one in the bootloader implementation itself, one
in the gadget.yaml bootloader setting, and one in Find(). Now we just have the
bootloader implementation and the gadget.yaml validator.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
Now we have a specific method on the Bootloader interface which tells Find()
whether the specific bootloader is actually present on the current system. This
will simplify future bootloader implementations to be able to return errors when
identifying if a bootloader is present on the system is more complicated a
question than just if the config file for that bootloader exists.
Signed-off-by: Ian Johnson <ian.johnson@canonical.com>
introduce bootloader.Options.Role to cover more generically
what was covered before by the Recovery and ExtractedRunKernelImage
flags
the default is RoleSole = "" which applies to the sole bootloader
for UC16/18
adjust tests and comments
The bootloader.Find() expects bootloader configuration to be present in the root
directory. However, when we are installing a run mode system, the bootloader
config is not present until after InstallBootConfig() gets called, which happens
only after the filesystem has been created and populated. However, when using
the ContentObserver to track trusted assets, we must know what the bootloader
is.
Add a helper for creating a bootloader based on what is carried by the gadget.
Move the basic checks for config file existence to Find().
Signed-off-by: Maciej Borzecki <maciej.zenon.borzecki@canonical.com>
When installing a boot configuration for recovery grub, pull the boot config
from internal assets. This makes sure that the boot config has predictable
content, controlled by snapd.
Signed-off-by: Maciej Borzecki <maciej.zenon.borzecki@canonical.com>
* When installing boot config assets, if the uboot.conf from the gadget
is empty, then assume that the gadget is not using uboot.env at all
and is instead using boot.src boot scripts, etc. and snapd should
install its own boot.sel uboot file for snap_kernel, etc.
* For UC20 bootloader options like NoSlashBoot and Recovery, change the
env file for u-boot to be /uboot/ubuntu/boot.sel and for
ExtractedRunKernelImage, use /boot/uboot/boot.sel.
Also update many unit tests for this, and port the image test to use
the real uboot bootloader instead of a mock one to test the new custom
uboot behavior.
Signed-off-by: Ian Johnson <person.uwsome@gmail.com>
This commit adds a new InstallBootCofig to the bootloader
interface. The bootloaders use the generic uc16 implementation
currently so nothing changes. But this will make it possible
to have different behavior for the install of the bootconfig
for uc20 where we will need to install a recovery boot config
and also a "run" mode boot config.
the only option for now is for knowing whether
ths bootloader is being used in prepare-image
this should help cleaning up the LittleKernel work
this is only an intermediate step toward refactoring image
vs boot/bootloader interaction
