To enable more efficient buffer reuse for HMAC operations three new
functions have been introduced. This change prevents the need to
reallocate memory for each HMAC operation:
- grub_crypto_hmac_reset(): reinitializes the hash contexts in the HMAC handle,
- grub_crypto_hmac_final(): provides the final HMAC result without freeing the
handle allowing it to be reused immediately,
- grub_crypto_hmac_free(): deallocates the HMAC handle and its associated memory.
To further facilitate buffer reuse ctx2 is now included within the HMAC handle
struct and the initialization of ctx2 is moved to grub_crypto_hmac_init().
The intermediate hash states, ctx and ctx2, for the inner and outer padded
keys are now cached. The grub_crypto_hmac_reset() restores these cached
states for new operations which avoids redundant hashing of the keys.
Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
A user can now specify UUID strings with dashes, instead of having to remove
dashes. This is backwards-compatibility preserving and also fixes a source
of user confusion over the inconsistency with how UUIDs are specified
between file system UUIDs and cryptomount UUIDs. Since cryptsetup, the
reference implementation for LUKS, displays and generates UUIDs with dashes
there has been additional confusion when using the UUID strings from
cryptsetup as exact input into GRUB does not find the expected cryptodisk.
A new function grub_uuidcasecmp() is added that is general enough to be used
other places where UUIDs are being compared.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Using the disk read hook mechanism, setup a read hook on the source disk
which will read from the given header file during the scan and recovery
cryptodisk backend functions. Disk read hooks are executed after the data
has been read from the disk. This is okay, because the read hook is given
the read buffer before its sent back to the caller. In this case, the hook
can then overwrite the data read from the disk device with data from the
header file sent in as the read hook data. This is transparent to the
read caller. Since the callers of this function have just opened the
source disk, there are no current read hooks, so there's no need to
save/restore them nor consider if they should be called or not.
This hook assumes that the header is at the start of the volume, which
is not the case for some formats (e.g. GELI). So GELI will return an
error if a detached header is specified. It also can only be used
with formats where the detached header file can be written to the
first blocks of the volume and the volume could still be unlocked.
So the header file can not be formatted differently from the on-disk
header. If these assumpts are not met, detached header file processing
must be specially handled in the cryptodisk backend module.
The hook will be called potentially many times by a backend. This is fine
because of the assumptions mentioned and the read hook reads from absolute
offsets and is stateless.
Also add a --header (short -H) option to cryptomount which takes a file
argument.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Note that cargs.search_uuid does not need to be initialized in various parts
of the cryptomount argument parsing, just once when cargs is declared with
a struct initializer. The previous code used a global variable which would
retain the value across cryptomount invocations.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The crypto device modules should only be setting up the crypto devices and
not getting user input. This has the added benefit of simplifying the code
such that three essentially duplicate pieces of code are merged into one.
Add documentation of passphrase option for cryptomount as it is now usable.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Previously, the cryptomount arguments were passed by global variable and
function call argument, neither of which are ideal. This change passes data
via a grub_cryptomount_args struct, which can be added to over time as
opposed to continually adding arguments to the cryptodisk scan and
recover_key.
As an example, passing a password as a cryptomount argument is implemented.
However, the backends are not implemented, so testing this will return a not
implemented error.
Also, add comments to cryptomount argument parsing to make it more obvious
which argument states are being handled.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The function grub_disk_get_size() is confusingly named because it actually
returns a sector count where the sectors are sized in the GRUB native sector
size. Rename to something more appropriate.
Suggested-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This makes it clear that the offset represents sectors, not bytes, in
order to improve readability.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This creates an alignment with grub_disk_t naming of the same field and is
more intuitive as to how it should be used.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Patrick Steinhardt <ps@pks.im>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
"Command for ...".
* grub-core/commands/hdparm.c (options): Use "Display" rather than
"Check" since we don't check anything.
* grub-core/commands/i386/cpuid.c (options): Clarify that long mode
is 64-bit one.
* grub-core/commands/search_wrap.c (options): Clarify the conditions.
* grub-core/disk/geli.c (grub_md_sha256_real): Fix typo.
(grub_md_sha512_real): Likewise.
