/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef KEYSTORE_KEYSTORE_SERVICE_H_
#define KEYSTORE_KEYSTORE_SERVICE_H_
#include <keystore/IKeystoreService.h>
#include <keystore/authorization_set.h>
#include "auth_token_table.h"
#include "keystore.h"
#include "keystore_keymaster_enforcement.h"
#include "operation.h"
#include "permissions.h"
namespace keystore {
class KeyStoreService : public android::BnKeystoreService, public android::IBinder::DeathRecipient {
typedef ::android::sp<::android::hardware::keymaster::V3_0::IKeymasterDevice> km_device_t;
public:
explicit KeyStoreService(KeyStore* keyStore) : mKeyStore(keyStore), mOperationMap(this) {}
void binderDied(const android::wp<android::IBinder>& who);
KeyStoreServiceReturnCode getState(int32_t userId) override;
KeyStoreServiceReturnCode get(const android::String16& name, int32_t uid,
hidl_vec<uint8_t>* item) override;
KeyStoreServiceReturnCode insert(const android::String16& name, const hidl_vec<uint8_t>& item,
int targetUid, int32_t flags) override;
KeyStoreServiceReturnCode del(const android::String16& name, int targetUid) override;
KeyStoreServiceReturnCode exist(const android::String16& name, int targetUid) override;
KeyStoreServiceReturnCode list(const android::String16& prefix, int targetUid,
android::Vector<android::String16>* matches) override;
KeyStoreServiceReturnCode reset() override;
KeyStoreServiceReturnCode onUserPasswordChanged(int32_t userId,
const android::String16& password) override;
KeyStoreServiceReturnCode onUserAdded(int32_t userId, int32_t parentId) override;
KeyStoreServiceReturnCode onUserRemoved(int32_t userId) override;
KeyStoreServiceReturnCode lock(int32_t userId) override;
KeyStoreServiceReturnCode unlock(int32_t userId, const android::String16& pw) override;
bool isEmpty(int32_t userId) override;
KeyStoreServiceReturnCode
generate(const android::String16& name, int32_t targetUid, int32_t keyType, int32_t keySize,
int32_t flags, android::Vector<android::sp<android::KeystoreArg>>* args) override;
KeyStoreServiceReturnCode import(const android::String16& name, const hidl_vec<uint8_t>& data,
int targetUid, int32_t flags) override;
KeyStoreServiceReturnCode sign(const android::String16& name, const hidl_vec<uint8_t>& data,
hidl_vec<uint8_t>* out) override;
KeyStoreServiceReturnCode verify(const android::String16& name, const hidl_vec<uint8_t>& data,
const hidl_vec<uint8_t>& signature) override;
/*
* TODO: The abstraction between things stored in hardware and regular blobs
* of data stored on the filesystem should be moved down to keystore itself.
* Unfortunately the Java code that calls this has naming conventions that it
* knows about. Ideally keystore shouldn't be used to store random blobs of
* data.
*
* Until that happens, it's necessary to have a separate "get_pubkey" and
* "del_key" since the Java code doesn't really communicate what it's
* intentions are.
*/
KeyStoreServiceReturnCode get_pubkey(const android::String16& name,
hidl_vec<uint8_t>* pubKey) override;
KeyStoreServiceReturnCode grant(const android::String16& name, int32_t granteeUid) override;
KeyStoreServiceReturnCode ungrant(const android::String16& name, int32_t granteeUid) override;
int64_t getmtime(const android::String16& name, int32_t uid) override;
KeyStoreServiceReturnCode duplicate(const android::String16& srcKey, int32_t srcUid,
const android::String16& destKey, int32_t destUid) override;
int32_t is_hardware_backed(const android::String16& keyType) override;
KeyStoreServiceReturnCode clear_uid(int64_t targetUid64) override;
KeyStoreServiceReturnCode addRngEntropy(const hidl_vec<uint8_t>& entropy) override;
KeyStoreServiceReturnCode generateKey(const android::String16& name,
const hidl_vec<KeyParameter>& params,
const hidl_vec<uint8_t>& entropy, int uid, int flags,
KeyCharacteristics* outCharacteristics) override;
KeyStoreServiceReturnCode
getKeyCharacteristics(const android::String16& name, const hidl_vec<uint8_t>& clientId,
const hidl_vec<uint8_t>& appData, int32_t uid,
KeyCharacteristics* outCharacteristics) override;
KeyStoreServiceReturnCode importKey(const android::String16& name,
const hidl_vec<KeyParameter>& params, KeyFormat format,
const hidl_vec<uint8_t>& keyData, int uid, int flags,
KeyCharacteristics* outCharacteristics) override;
void exportKey(const android::String16& name, KeyFormat format,
const hidl_vec<uint8_t>& clientId, const hidl_vec<uint8_t>& appData, int32_t uid,
android::ExportResult* result) override;
void begin(const sp<android::IBinder>& appToken, const android::String16& name,
KeyPurpose purpose, bool pruneable, const hidl_vec<KeyParameter>& params,
const hidl_vec<uint8_t>& entropy, int32_t uid,
android::OperationResult* result) override;
void update(const sp<android::IBinder>& token, const hidl_vec<KeyParameter>& params,
const hidl_vec<uint8_t>& data, android::OperationResult* result) override;
void finish(const sp<android::IBinder>& token, const hidl_vec<KeyParameter>& params,
const hidl_vec<uint8_t>& signature, const hidl_vec<uint8_t>& entropy,
android::OperationResult* result) override;
KeyStoreServiceReturnCode abort(const sp<android::IBinder>& token) override;
bool isOperationAuthorized(const sp<android::IBinder>& token) override;
KeyStoreServiceReturnCode addAuthToken(const uint8_t* token, size_t length) override;
KeyStoreServiceReturnCode attestKey(const android::String16& name,
const hidl_vec<KeyParameter>& params,
hidl_vec<hidl_vec<uint8_t>>* outChain) override;
KeyStoreServiceReturnCode attestDeviceIds(const hidl_vec<KeyParameter>& params,
hidl_vec<hidl_vec<uint8_t>>* outChain) override;
KeyStoreServiceReturnCode onDeviceOffBody() override;
private:
static const int32_t UID_SELF = -1;
/**
* Prune the oldest pruneable operation.
*/
bool pruneOperation();
/**
* Get the effective target uid for a binder operation that takes an
* optional uid as the target.
*/
uid_t getEffectiveUid(int32_t targetUid);
/**
* Check if the caller of the current binder method has the required
* permission and if acting on other uids the grants to do so.
*/
bool checkBinderPermission(perm_t permission, int32_t targetUid = UID_SELF);
/**
* Check if the caller of the current binder method has the required
* permission and the target uid is the caller or the caller is system.
*/
bool checkBinderPermissionSelfOrSystem(perm_t permission, int32_t targetUid);
/**
* Check if the caller of the current binder method has the required
* permission or the target of the operation is the caller's uid. This is
* for operation where the permission is only for cross-uid activity and all
* uids are allowed to act on their own (ie: clearing all entries for a
* given uid).
*/
bool checkBinderPermissionOrSelfTarget(perm_t permission, int32_t targetUid);
/**
* Helper method to check that the caller has the required permission as
* well as the keystore is in the unlocked state if checkUnlocked is true.
*
* Returns NO_ERROR on success, PERMISSION_DENIED on a permission error and
* otherwise the state of keystore when not unlocked and checkUnlocked is
* true.
*/
KeyStoreServiceReturnCode checkBinderPermissionAndKeystoreState(perm_t permission,
int32_t targetUid = -1,
bool checkUnlocked = true);
bool isKeystoreUnlocked(State state);
/**
* Check that all keymaster_key_param_t's provided by the application are
* allowed. Any parameter that keystore adds itself should be disallowed here.
*/
bool checkAllowedOperationParams(const hidl_vec<KeyParameter>& params);
ErrorCode getOperationCharacteristics(const hidl_vec<uint8_t>& key, km_device_t* dev,
const AuthorizationSet& params, KeyCharacteristics* out);
/**
* Get the auth token for this operation from the auth token table.
*
* Returns ::NO_ERROR if the auth token was set or none was required.
* ::OP_AUTH_NEEDED if it is a per op authorization, no
* authorization token exists for that operation and
* failOnTokenMissing is false.
* KM_ERROR_KEY_USER_NOT_AUTHENTICATED if there is no valid auth
* token for the operation
*/
KeyStoreServiceReturnCode getAuthToken(const KeyCharacteristics& characteristics,
uint64_t handle, KeyPurpose purpose,
const HardwareAuthToken** authToken,
bool failOnTokenMissing = true);
/**
* Add the auth token for the operation to the param list if the operation
* requires authorization. Uses the cached result in the OperationMap if available
* otherwise gets the token from the AuthTokenTable and caches the result.
*
* Returns ::NO_ERROR if the auth token was added or not needed.
* KM_ERROR_KEY_USER_NOT_AUTHENTICATED if the operation is not
* authenticated.
* KM_ERROR_INVALID_OPERATION_HANDLE if token is not a valid
* operation token.
*/
KeyStoreServiceReturnCode addOperationAuthTokenIfNeeded(const sp<android::IBinder>& token,
AuthorizationSet* params);
/**
* Translate a result value to a legacy return value. All keystore errors are
* preserved and keymaster errors become SYSTEM_ERRORs
*/
KeyStoreServiceReturnCode translateResultToLegacyResult(int32_t result);
void addLegacyBeginParams(const android::String16& name, AuthorizationSet* params);
KeyStoreServiceReturnCode doLegacySignVerify(const android::String16& name,
const hidl_vec<uint8_t>& data,
hidl_vec<uint8_t>* out,
const hidl_vec<uint8_t>& signature,
KeyPurpose purpose);
/**
* Upgrade a key blob under alias "name", returning the new blob in "blob". If "blob"
* previously contained data, it will be overwritten.
*
* Returns ::NO_ERROR if the key was upgraded successfully.
* KM_ERROR_VERSION_MISMATCH if called on a key whose patch level is greater than or
* equal to the current system patch level.
*/
KeyStoreServiceReturnCode upgradeKeyBlob(const android::String16& name, uid_t targetUid,
const AuthorizationSet& params, Blob* blob);
::KeyStore* mKeyStore;
OperationMap mOperationMap;
keystore::AuthTokenTable mAuthTokenTable;
KeystoreKeymasterEnforcement enforcement_policy;
};
}; // namespace keystore
#endif // KEYSTORE_KEYSTORE_SERVICE_H_