Now that vold uses Keystore2 rather than the Keymaster HAL directly, and
also the new version of Keymaster is called "KeyMint" instead, replace
most of the references to Keymaster in vold with Keystore.
(I decided not to include the "2" in most places, as it seemed
unnecessarily precise in most places, and it would be something that
might need to keep being updated. Only Keystore.{cpp,h} really need to
care about the version number.)
I didn't rename many things in cryptfs.cpp, as that file will be going
away soon anyway. I also left "wait_for_keymaster" and "vdc keymaster
earlyBootEnded" as-is for now, as those are referenced outside vold.
Bug: 183669495
Change-Id: I92cd648fae09f8c9769f7cf34dbf6c6e956be4e8
storeKey() is no longer used outside KeyStorage.cpp, so make it a static
function. Also fix the documentation for storeKey() (e.g. it's no
longer safe to directly move/rename directories created by storeKey() --
one must use RenameKeyDir() instead).
No functional changes.
[ebiggers@ - cleaned up slightly from satyat@'s original change]
Bug: 190398249
Change-Id: I85918359e77bef414dfddfe5ded30fcde6514013
Make fixate_user_ce_key() use RenameKeyDir() to rename key directories
so that any deferred commits for these directories are also updated
appropriately.
This fixes a potential lost Keymaster key upgrade if a key were to be
re-wrapped while a user data checkpoint is pending. This isn't a huge
issue as the key will just get upgraded again, but this should be fixed.
[ebiggers@ - cleaned up slightly from satyat@'s original change]
Bug: 190398249
Change-Id: Ic6c5b4468d07ab335368e3d373916145d096af01
Comparing paths is error-prone (e.g. "/foo/bar" vs "/foo//bar"), so
entries in key_dirs_to_commit are compared using inode and device
number. However RenameKeyDir() breaks this rule and compares raw paths.
Avoid this quirk by finding the entry in the list to replace before
doing the rename.
This doesn't fix any known problem, as vold is fairly consistent with
its paths in practice; this is just a robustness improvement.
Bug: 190398249
Change-Id: I3ce2c0119cb2012ac9d12849570e56600bc23867
storeKeyAtomically() stores keys in a temp directory before renaming
that directory to the real target directory. However when the key is
stored in the temporary directory, the Keymaster storage key might get
upgraded, and it's possible that the temp directory is scheduled for a
deferred commit. storeKeyAtomically() renames that temp directory, but
doesn't update the list of directories marked for deferred commit.
This patch fixes this by removing the temp directory from the list and
adding the real target directory to that list instead.
This bug was found when trying to switch from using the guest keymint to
using the host remote keymint implementation on cuttlefish
(aosp/1701925). The device triggers this bug (and boots to recovery)
when aosp/1701925 is cherry-picked.
Co-Developed-By: Eric Biggers <ebiggers@google.com>
Test: Cuttlefish boots with and without aosp/1701925
Change-Id: I3b6fd6ad32ed415da94423cca6f5a121c16472f2
Now that the salt and hardware auth token related code has been removed,
we can remove the associated (and now unused) constants.
Also cleanup some comments and remove includes related to hardware auth
token support.
Bug: 181910578
Test: Cuttlefish boots.
Change-Id: I3733d5c6bbf6989adc165c554ee53faa2484f4b6
stretchSecret() no longer uses the "salt" parameter, so remove it and
simplify callers
Bug: 181910578
Test: Cuttlefish boots.
Change-Id: Ic2d0742b22b98a66da37f435e274c9d385b8e188
Make vold use keystore2 for all its operations instead of directly using
keymaster. This way, we won't have any clients that bypass keystore2,
and we'll no longer need to reserve a keymaster operation for vold.
Note that we now hardcode "SecurityLevel::TRUSTED_ENVIRONMENT" (TEE)
when talking to Keystore2 since Keystore2 only allows TEE and STRONGBOX.
Keystore2 presents any SOFTWARE implementation as a TEE to callers when
no "real" TEE is present. As far as storage encryption is concerned,
there's no advantage to using a STRONGBOX when a "real" TEE is present,
and a STRONGBOX can't be present if a "real" TEE isn't, so asking
Keystore2 for a TEE is the best we can do in any situation.
The difference in behaviour only really affects the full disk encryption
code in cryptfs.cpp, which used to explicitly check that the keymaster
device is a "real" TEE (as opposed to a SOFTWARE implementation) before
using it (it can no longer do so since Keystore2 doesn't provide a way
to do this).
A little code history digging (7c49ab0a0b in particular) shows that
cryptfs.cpp cared about two things when using a keymaster.
- 1) that the keys generated by the keymaster were "standalone" keys -
i.e. that the keymaster could operate on those keys without
requiring /data or any other service to be available.
- 2) that the keymaster was a non-SOFTWARE implementation so that things
would still work in case a "real" TEE keymaster was ever somehow
added to the device after first boot.
Today, all "real" TEE keymasters always generate "standalone" keys, and
a TEE has been required in Android devices since at least Android N. The
only two exceptions are Goldfish and ARC++, which have SOFTWARE
keymasters, but both those keymasters also generate "standalone" keys.
We're also no longer worried about possibly adding a "real" TEE KM to
either of those devices after first boot. So there's no longer a reason
cryptfs.cpp can't use the SOFTWARE keymaster on those devices.
There's also already an upgrade path in place (see
test_mount_encrypted_fs() in cryptfs.cpp) to upgrade the kdf that's
being used once a TEE keymaster is added to the device. So it's safe for
cryptfs.cpp to ask for a TEE keymaster from Keystore2 and use it
blindly, without checking whether or not it's a "real" TEE, which is why
Keymaster::isSecure() just returns true now. A future patch will remove
that function and simplify its callers.
Bug: 181910578
Test: cuttlefish and bramble boot. Adding, switching between, stopping
and removing users work.
Change-Id: Iaebfef082eca0da8a305043fafb6d85e5de14cf8
HardwareAuthTokens are no longer used by vold since Android P. So remove
the auth token parameter from vold. This patch doesn't remove the token
from IVold.aidl, and the methods in VoldNativeService.cpp return an
error if a non-empty auth token is passed to them.
Bug: 181910578
Test: cuttlefish and bramble boot with patch
Change-Id: I1a9f54e10f9efdda9973906afd0a5de5a699ada5
The error messages that are printed when probing for rollback resistance
support on a device that doesn't support rollback-resistant keys can
make it sound like something is going wrong. Print a WARNING message
afterwards to try to make it clear what is going on. Also adjust or add
DEBUG messages when starting to generate each key so that it's easier to
distinguish the log messages for different key generation operations.
Bug: 182815123
Test: boot on device that doesn't support rollback-resistant keys and
check log.
Change-Id: I37a13eb5c1e839fb94581f3e7ec1cd8da0263d2b
When an FBE or metadata encryption key is created, it's important that
it be persisted to disk right away; otherwise the device may fail to
boot after an unclean shutdown. storeKey() has the needed fsync()s.
However, storeKeyAtomically() doesn't, as it doesn't fsync() the parent
directory of key_path after it renames tmp_path to it.
Two callers do fsync() the parent directory themselves, but others
don't. E.g., the metadata encryption key doesn't get properly synced.
Therefore, add the needed fsync() to storeKeyAtomically() so that it
gets done for everyone.
Also remove the now-unneeded fsync()s from the two callers that did it
themselves.
Change-Id: I342ebd94f0a3d2bf3a7a443c35b6bda0f12e1ab2
With this change, vold exposes an API that may be used to bind key
storage encryption keys to a given seed value. The seed value passed to
vold must be consistent across reboots, or key storage keys will not be
derived consistently. The seed is expected to be set very early in boot,
prior to the use of any key storage encryption keys.
This feature is intended to be used for embedded applications such as
in autos, where the seed may be provided by some other component of the
system. In such systems, there is a default user that is automatically
signed in without a PIN or other credentials. By binding the file
encryption to a platform-provided seed, the default user's data gains
additional protection against removal of the Android embedded device
from the integrated system.
Bug: 157501579
Test: Set seed at startup via init.rc. Seed changes fail as expected.
Change-Id: I9b048ec5e045b84c45883724ace2356d4ef6244d
Remove the error-prone 'keepOld' parameter, and instead make begin()
(renamed to BeginKeymasterOp()) do all the key upgrade handling.
Don't handle /data and /metadata differently anymore. Previously, when
a checkpoint is active, key blob files were replaced on /data
immediately; only the actual Keymaster key deletion was delayed until
checkpoint commit. But it's easier to just delay the key blob file
replacement too, as we have to implement that for /metadata anyway.
Also be more vigilant about deleting any leftover upgraded keys.
Test: Tested on bramble using an OTA rvc-d1-release => master. In OTA
success case, verified via logcat that the keys were upgraded and
then were committed after the boot succeeded. In OTA failure
case, verified that the device still boots -- i.e., the old keys
weren't lost. Verified that in either case, no
keymaster_key_blob_upgraded files were left over. Finally, also
tried 'pm create-user' and 'pm remove-user' and verified via
logcat that the Keymaster keys still get deleted.
Change-Id: Ic9c3e63e0bcae0c608fc79050ca4a1676b3852ee
Generate a storage key without rollback_resistance when device doesnt
support the corresponding tag.
Bug: 168527558
Change-Id: Iaf27c64dba627a31c9cbd9178458bf6785d00251
To prevent keys from being compromised if an attacker
acquires read access to kernel memory, some inline
encryption hardware supports protecting the keys in
hardware without software having access to or the
ability to set the plaintext keys. Instead, software
only sees "wrapped keys", which may differ on every boot.
'wrappedkey_v0' fileencryption flag is used to denote
that the device supports inline encryption hardware that
supports this feature. On such devices keymaster is used
to generate keys with STORAGE_KEY tag and export a
per-boot ephemerally wrapped storage key to install it in
the kernel.
The wrapped key framework in the linux kernel ensures the
wrapped key is provided to the inline encryption hardware
where it is unwrapped and the file contents key is derived
to encrypt contents without revealing the plaintext key in
the clear.
Test: FBE validation with Fscrypt v2 + inline crypt + wrapped
key changes kernel.
Bug: 147733587
Change-Id: I1f0de61b56534ec1df9baef075acb74bacd00758
This CL updates vold to use the Keymaster 4.1 interface, but does not
yet call any of the new methods.
Test: Boot the device
Change-Id: I4574a2f6eead3b71d1e89488b496b734694620c7
Merged-In: I4574a2f6eead3b71d1e89488b496b734694620c7
Don't delete keys in checkpointing mode. Instead wait until the
checkpoint has been committed.
Bug: 134631661
Test: Flash A with a working build. Flash B with a broken build. Test
that the device rolls back to A without getting sent to recovery.
Merged-In: Ie5fc2d098355e2d095c53e9a95a6a8c7ab7ed051
Change-Id: Ie5fc2d098355e2d095c53e9a95a6a8c7ab7ed051
Remove static definition of writeStringToFile, and
move it from KeyStorage to Utils
(cherry picked from commit 0bd2d11692)
Bug: 71810347
Test: Build pass and reboot stress test.
Change-Id: I38bfd27370ac2372e446dc699f518122e73c6877
Merged-In: I38bfd27370ac2372e446dc699f518122e73c6877
The boot failure symptom is reproduced on Walleye devices. System boots
up after taking OTA and try to upgrade key, but keymaster returns "failed
to ugprade key". Device reboots to recovery mode because of the failure,
and finally trapped in bootloader screen. Possible scenario is:
(After taking OTA)
vold sends old key and op=UPGRADE to keymaster
keymaster creates and saves new key to RPMB, responses new key to vold
vold saves new key as temp key
vold renames temp key to main key -------------- (1) -- still in cache
vold sends old key and op=DELETE_KEY to keymaster
keymaster removes old key from RPMB ------------ (2) -- write directly to RPMB
==> SYSTEM INTERRUPTED BY CRASH OR SOMETHING; ALL CACHE LOST.
==> System boots up, key in RPMB is deleted but key in storage is old key.
Solution: A Fsync is required between (1) and (2) to cover this case.
Detail analysis: b/124279741#comment21
Bug: 112145641
Bug: 124279741
Test: Insert fault right after deleteKey in vold::begin (KeyStorage.cpp),
original boot failure symptom is NOT reproducible.
Change-Id: Ib8c349d6d033f86b247f4b35b8354d97cf249d26
This adds the ability to upgrade a key and retain the
old one for rollback purposes. We delete the old key
if we boot successfully and delete the new key if we
do not.
Test: Enable checkpointing and test rolling back
between two versions
Bug: 111020314
Change-Id: I19f31a1ac06a811c0644fc956e61b5ca84e7241a
This CL changes vold from using a KM3 device directly to using the KM4
support wrapper from the KM4 support library, which supports both KM3
and KM4 devices (KM0, 1 and 2 devices are still supported as well,
because the default KM3 device is a wrapper that uses them).
In addition, I found myself getting confused about which "Keymaster"
types were locally-defined vold keymaster types and which were from
the KM4 HAL and support library, so I changd the approach to
referencing the latter, so all of them are qualified with the "km::"
namespace reference.
Test: Build & boot
Change-Id: I08ed5425641e7496f8597d5716cb3cd0cbd33a7f
This is temporary. Keystore is in the process of being upgraded to use
the new Keymaster 4.0 HAL, and I want to leave vold alone, using
Keymaster 3.0 for the moment. This CL just copies relevant bits of
keystore support utilities into vold, so it can stop depending on the
copies from keystore.
After the keystore update is complete, vold will be changed either to
use Keymaster 4.0 or -- more likely -- to use keystore rather than
talking to Keymaster directly. At that point the files added by this CL
will be deleted.
Test: Device boots and successfully decrypts /data
Change-Id: I73f6d4cc4c5e20d89d7ac37d29d025bf279f9e12
Protect all per-volume-per-user keys with a per-volume key, which is
forgotten when the volume is forgotten. This means that the user's key
is securely lost even when their storage is encrypted at forgetting
time.
Bug: 25861755
Test: create a volume, forget it, check logs and filesystem.
Change-Id: I8df77bc91bbfa2258e082ddd54d6160dbf39b378
If it's not a keymaster key, don't try to invalidate or delete the key
blob.
Bug: 25861755
Test: Create and forget a volume, check logs and files.
Change-Id: If8bfb1a9ab41e6c7e46bc311eb296242e56d264f
std::vector with custom zeroing allocator is used instead of
std::string for data that can contain encryption keys.
Bug: 64201177
Test: manually created a managed profile, changed it's credentials
Test: manually upgraded a phone with profile from O to MR1.
Change-Id: Ic31877049f69eba9f8ea64fd99acaaca5a01d3dd
This is used by LockSettingsService to delete sensitive credential files.
Bug: 34600579
Test: manual - change device lock under synthetic password, verify
old data on disk is erased.
Change-Id: I5e11b559ad8818bd2ad2b321d67d21477aab7555
Change to use WaitForProperty API to wait for vold.post_fs_data_done
Also change cryptfs to C++
Bug: 35425974
Test: mma, marlin/angler boot
Change-Id: Id821f2035788fcc91909f296c83c871c67571de3
Keymaster but in-process crypto.
Bug: 33384925
Test: manual for now: patch KeyAuthentication.usesKeymaster() to always return true;
flash a FBE device, add a device PIN, reboot and verify PIN can unlock FBE.
Then clear device PIN, reboot and verify FBE is unlocked automatically.
In both cases, check there is no keymaster_key_blob in
/data/misc/vold/user_keys/ce/0/current/
Unit tests to be added.
Change-Id: Ia94e2b39d60bfd98c7a8347a5ba043eeab6928c5
Don't rely on cryptographic binding of secdiscard to key; securely
delete the other information needed to reconstruct the key too.
Bug: 26021231
Change-Id: If03d2c051b0ec2fdcb5c6f70bde7e3287424f216
Avoid a timeout error by extending the time allowed between getting
the auth token and decrypting the key from five to thirty seconds.
Bug: 28398766
Change-Id: I1dbb9e0e33707e7de4c1720ad1b8e153c77094b2
The formatting here is inconsistent with Android house style; use
clang-format to bring it back into line.
Change-Id: Id1fe6ff54e9b668ca88c3fc021ae0a5bdd1327eb
Google/Android C++ style requires that arguments passed in for writing
should be pointers, not references, so that it's visible in the caller
that they'll be written to.
Bug: 27566014
Change-Id: I5cd55906cc4b2f61c8b97b223786be0b3ce28862
A bug meant that the auth token wasn't being used; it turns out that
in order to use it we need to do things slightly differently.
Bug: 27496553
Change-Id: I0f0ab77fed31b92a79eba4acf488cb098691b4be
- catch errors in looking for the keyring
- static_assert to prevent a buffer overrun
- remove obsolete, misleading comment
- dial down priority of some log messages
- explain why we ignore some errors
- idiomatic C++11
Bug: 27552432
Change-Id: Ic3ee05b41eae45e7c6b571a459b326a483663526
