The credstore system daemon is sitting below the Identity Credential
Framework APIs and on top of the Identity Credential HALs. Its main
job is to store credential data and provide a way for applications to
communicate with the secure hardware abstracted by the HAL.
This daemon runs as an unprivileged user, credstore.
The auth-tokens needed by credstore are supplied by keystore and this
CL includes the requisite changes to keystore for this to work.
Bug: 111446262
Test: CTS tests for Framework APIs
Change-Id: Ieb4d59852a143482436a1c418c25ed96e25c0047
This patch transitions keystore a threading model with one dispatcher
thread and one worker thread per keymaster instance, i.e. fallback, TEE,
Strongbox (if available). Singleton objects, such as the user state
database, the enforcement policy, and grant database have been moved to
KeyStore and were made concurrency safe.
Other noteworthy changes in this patch:
* Cached key characteristics. The key characteristics file used to hold
a limited set of parameters used generate or import the key. This
patch introduces a new blob type that holds full characteristics as
returned by generate, import, or getKeyCharacteristics, with the
original parameters mixed into the software enforced list. When
keystore encounters a lagacy characteristics file it will grab the
characteristics from keymaster, merge them with the cached parameters,
and update the cache file to the new format. If keystore encounters
the new cache no call to keymaster will be made for retrieving the
key characteristics.
* Changed semantic of list. The list call takes a prefix used for
filtering key entries. By the old semantic, list would return a list
of aliases stripped of the given prefix. By the new semantic list
always returns a filtered list of full alias string. Callers may
strip prefixes if they are so inclined.
* Entertain per keymaster instance operation maps. With the introduction
of Strongbox keystore had to deal with multiple keymaster instances.
But until now it would entertain a single operations map. Keystore
also enforces the invariant that no more than 15 operation slots are
used so there is always a free slot available for vold. With a single
operation map, this means no more than 15 slots can ever be used
although with TEE and Strongbox there are a total of 32 slots. With
strongbox implementation that have significantly fewer slots we see
another effect of the single operation map. If a slot needs to be
freed on Stronbox but the oldest operations are on TEE, the latter
will be unnecessarily pruned before a Strongbox slot is freed up.
With this patch each keymaster instance has its own operation map and
pruning is performed on a per keymaster instance basis.
* Introduce KeyBlobEntries which are independent from files. To allow
concurrent access to the key blob data base, entries can be
individually locked so that operations on entries become atomic.
LockedKeyBlobEntries are move only objects that track ownership of an
Entry on the stack or in functor object representing keymaster worker
requests. Entries must only be locked by the dispatcher Thread. Worker
threads can only be granted access to a LockedKeyBlobEntry by the
dispatcher thread. This allows the dispatcher thread to execute a
barrier that waits until all locks held by workers have been
relinquished to perform blob database maintenance operations, e.g.,
clearing a uid of all entries.
* Verification tokens are now acquired asynchronously. When a begin
operation requires a verification token a request is submitted to the
other keymaster worker while the begin call returns. When the
operation commences with update or finish, we block until the
verification token becomes available.
As of this patch the keystore IPC interface is still synchronous. That
is, the dispatcher thread dispatches a request to a worker and then
waits until the worker has finished. In a followup patch the IPC
interface shall be made asynchronous so that multiple requests may be in
flight.
Test: Ran full CTS test suite
atest android.keystore.cts
Bug: 111443219
Bug: 110495056
Change-Id: I305e28d784295a0095a34810d83202f7423498bd
This commit replaces <cutils/log.h> and <utils/Log.h> with <log/log.h>.
Background:
<cutils/log.h> has been moved to <log/log.h> for a while. Both
<cutils/log.h> and <utils/Log.h> simply includes <log/log.h> for
backward compatibility. This commit is a part of the effort to remove
<cutils/log.h> and <utils/Log.h> from the source tree eventually.
Bug: 78370064
Test: lunch aosp_walleye-userdebug && cd system/security && mma
Change-Id: I798f06d78e2cc5cd197727c0bcdd05c87d769a90
auth_token_table tests did not make the transition to hidle types and
were broken.
Noww they use the hidle types as well.
Also this patch fixes an awkward ownership transfer of an object
referred to by a const pointer and reduses the use of the type hw_auth_token.
Test: Ran all keystore CTS test as well as the fixed auth_token_table
tests
Bug: 68149839
Change-Id: Ia69a80fad12edc134646a7b340f8e27ea4da2210
We observed on some Pixel C that they sometimes generate auth token with
a stuck timestamp value. Since the timestamp value does not increase,
newer auth token is not considered "superceding" old auth tokens and keystore
end up retrieving older auth tokens which are then treated as expired due to
its time_received value being too old.
We workaround this issue by comparing both the timestamp (which is part of
auth token) and the time_received (which is a monotonic clock value at the
time auth token is sent to keystore). So a new auth token with stuck timestamp
value but newer time_received still supercedes older auth tokens.
This is actually sufficient to workaround the issue on Pixel C, since the stuck
timestamp value is returned by the secure RTC, whose value is also used by
keymaster TA to check key authorization. In other words, the auth token is
still good to authorize auth-bound keys, even with a stuck timestamp value.
This does mean that on the affected Pixel C, auth-bound keys are not enforced
at TrustZone leve, but merely a logical check in keystore daemon.
Bug: 65283496
Test: boot device, unlock successfully
Change-Id: I0b9d5463e94241bfaf552dcb31fea04ee966596c
HardwareAuthToken.timestamp is uint64_t but got truncated to uint32_t by
timestamp_host_order(). Also add some logging to undertand the issue of
bad auth token on ryu.
Bug: 65283496
Test: builds and runs
Change-Id: Ia51d0880f47594e6ab02e46bec270ee68dc5823f
Auth tokens have an unfortunate dual character. To most of the system
they are opaque blobs that are intended only to be obtained from one
HAL (e.g. gatekeeper or fingerprint) and passed to another
HAL (keymaster), but keystore actually needs to extract some bits of
information from them in order to determine which of the available blobs
should be provided for a given keymaster key operation.
This CL adds a method that resolves this dual nature by moving the
responsibility of parsing blobs to the HAL so that no component of the
framework has to make any assumptions about their content and all can
treat them as fully opaque. This still means that the various HAL
implementers have to agree on content, but they also have to agree on an
HMAC key which much be securely distributed to all at every boot, so
asking them to agree on an auth token format is perfectly
acceptable. But now the Android system doesn't have to care about the
format.
Bug: 32962548
Test: CTS tests pass, plus manual testing.
Change-Id: I2ab4b4fbea1425fc08aa754fc10f8e386899af25
This patch ports keystore to the HIDL based binderized keymaster HAL.
Keystore has no more dependencies on legacy keymaster headers, and
therefore data structures, constant declarations, or enums. All
keymaster related data structures and enums used by keystore are the
once defined by the HIDL based keymaster HAL definition. In the process
of porting, keystore underwent some changes:
* Keystore got a new implementation of AuthorizationSet that is fully
based on the new HIDL data structures. Key parameters are now either
organised as AuthorizationSets or hidl_vec<KeyParameter>. (Formerly,
this was a mixture of keymaster's AuthorizationSet,
std::vec<keymaster_key_param_t>, and keymaster_key_param_set_t.) The
former is used for memory management and provides algorithms for
assembling, joining, and subtracting sets of parameters. The latter
is used as wire format for the HAL IPC; it can wrap the memory owned
by an AuthorizationSet for this purpose. The AuthorizationSet is
accompanied by a new implementation of type safe functions for
creating and accessing tagged key parameters,
Authorizations (keystore/keymaster_tags.h).
* A new type (KSSReturnCode) was introduced that wraps keystore service
response codes. Keystore has two sets of error codes. ErrorCode
errors are less than 0 and use 0 as success value. ResponseCode
errors are greater than zero and use 1 as success value. This patch
changes ResponseCode to be an enum class so that is no longer
assignable to int without a cast. The new return type can only be
initialized by ResponseCode or ErrorCode and when accessed as int32_t,
which happens on serialization when the response is send to a client,
the success values are coalesced onto 1 as expected by the
clients. KSSreturnCode is also comparable to ResponseCode and
ErrorCode, and the predicate isOk() returns true if it was initialized
with either ErrorCode::OK (0) or ReponseCode::NO_ERROR (1).
* A bug was fixed, that caused the keystore verify function to return
success, regardless of the input, internal errors, or lack of
permissions.
* The marshalling code in IKeystoreService.cpp was rewritten. For data
structures that are known to keymaster, the client facing side of
keystore uses HIDL based data structures as (target) source
for (un)marshaling to avoid further conversion. hidl_vecs are used to
wrap parcel memory without copying and taking ownership where
possible.
* Explicit use of malloc is reduced (malloc was required by the C nature
of the old HAL). The new implementations avoid explicit use of
malloc/new and waive the use of pointers for return values. Instead,
functions return by value objects that take ownership of secondary
memory allocations where required.
Test: runtest --path=cts/tests/tests/keystore/src/android/keystore/cts
Bug: 32020919
Change-Id: I59d3a0f4a6bdf6bb3bbf791ad8827c463effa286
There are three changes in this CL:
1. Persist all characteristics provided at the time of key creation.
We do this to avoid device-specific keymaster implementations
stripping keys they are not aware of.
2. Add an onDeviceOffBody API method that will be called whenever a
wearable device is detected to have been removed.
3. Check whether a key was created with TAG_ALLOW_WHILE_ON_BODY and
the device has gone off-body since the last auth event when
deciding whether it can be used.
BUG: 30701680
BUG: 28911985
Change-Id: I6be3af3dee8e576fe713dfdd726502d8b333f224
Keystore will use this to manage authentication tokens and identify the
correct one to be submitted to keymaster to authorize an
authentication-requiring operation.
Bug: 19511945
Change-Id: Ie6d2db4bebfa3734e535498d20928b8f8965963c
