/*
* 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 <keymaster/authorization_set.h>
#include "auth_token_table.h"
#include "keystore.h"
#include "keystore_keymaster_enforcement.h"
#include "operation.h"
#include "permissions.h"
namespace android {
class KeyStoreService : public BnKeystoreService, public IBinder::DeathRecipient {
public:
KeyStoreService(KeyStore* keyStore) : mKeyStore(keyStore), mOperationMap(this) {}
void binderDied(const wp<IBinder>& who);
int32_t getState(int32_t userId);
int32_t get(const String16& name, int32_t uid, uint8_t** item, size_t* itemLength);
int32_t insert(const String16& name, const uint8_t* item, size_t itemLength, int targetUid,
int32_t flags);
int32_t del(const String16& name, int targetUid);
int32_t exist(const String16& name, int targetUid);
int32_t list(const String16& prefix, int targetUid, Vector<String16>* matches);
int32_t reset();
int32_t onUserPasswordChanged(int32_t userId, const String16& password);
int32_t onUserAdded(int32_t userId, int32_t parentId);
int32_t onUserRemoved(int32_t userId);
int32_t lock(int32_t userId);
int32_t unlock(int32_t userId, const String16& pw);
bool isEmpty(int32_t userId);
int32_t generate(const String16& name, int32_t targetUid, int32_t keyType, int32_t keySize,
int32_t flags, Vector<sp<KeystoreArg>>* args);
int32_t import(const String16& name, const uint8_t* data, size_t length, int targetUid,
int32_t flags);
int32_t sign(const String16& name, const uint8_t* data, size_t length, uint8_t** out,
size_t* outLength);
int32_t verify(const String16& name, const uint8_t* data, size_t dataLength,
const uint8_t* signature, size_t signatureLength);
/*
* 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.
*/
int32_t get_pubkey(const String16& name, uint8_t** pubkey, size_t* pubkeyLength);
int32_t grant(const String16& name, int32_t granteeUid);
int32_t ungrant(const String16& name, int32_t granteeUid);
int64_t getmtime(const String16& name, int32_t uid);
int32_t duplicate(const String16& srcKey, int32_t srcUid, const String16& destKey,
int32_t destUid);
int32_t is_hardware_backed(const String16& keyType);
int32_t clear_uid(int64_t targetUid64);
int32_t addRngEntropy(const uint8_t* data, size_t dataLength);
int32_t generateKey(const String16& name, const KeymasterArguments& params,
const uint8_t* entropy, size_t entropyLength, int uid, int flags,
KeyCharacteristics* outCharacteristics);
int32_t getKeyCharacteristics(const String16& name, const keymaster_blob_t* clientId,
const keymaster_blob_t* appData, int32_t uid,
KeyCharacteristics* outCharacteristics);
int32_t importKey(const String16& name, const KeymasterArguments& params,
keymaster_key_format_t format, const uint8_t* keyData, size_t keyLength,
int uid, int flags, KeyCharacteristics* outCharacteristics);
void exportKey(const String16& name, keymaster_key_format_t format,
const keymaster_blob_t* clientId, const keymaster_blob_t* appData, int32_t uid,
ExportResult* result);
void begin(const sp<IBinder>& appToken, const String16& name, keymaster_purpose_t purpose,
bool pruneable, const KeymasterArguments& params, const uint8_t* entropy,
size_t entropyLength, int32_t uid, OperationResult* result);
void update(const sp<IBinder>& token, const KeymasterArguments& params, const uint8_t* data,
size_t dataLength, OperationResult* result);
void finish(const sp<IBinder>& token, const KeymasterArguments& params,
const uint8_t* signature, size_t signatureLength, const uint8_t* entropy,
size_t entropyLength, OperationResult* result);
int32_t abort(const sp<IBinder>& token);
bool isOperationAuthorized(const sp<IBinder>& token);
int32_t addAuthToken(const uint8_t* token, size_t length);
int32_t attestKey(const String16& name, const KeymasterArguments& params,
KeymasterCertificateChain* outChain) 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.
*/
int32_t checkBinderPermissionAndKeystoreState(perm_t permission, int32_t targetUid = -1,
bool checkUnlocked = true);
bool isKeystoreUnlocked(State state);
bool isKeyTypeSupported(const keymaster2_device_t* device, keymaster_keypair_t keyType);
/**
* 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 std::vector<keymaster_key_param_t>& params);
keymaster_error_t getOperationCharacteristics(const keymaster_key_blob_t& key,
const keymaster2_device_t* dev,
const std::vector<keymaster_key_param_t>& params,
keymaster_key_characteristics_t* 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
*/
int32_t getAuthToken(const keymaster_key_characteristics_t* characteristics,
keymaster_operation_handle_t handle, keymaster_purpose_t purpose,
const hw_auth_token_t** authToken, bool failOnTokenMissing = true);
void addAuthToParams(std::vector<keymaster_key_param_t>* params, const hw_auth_token_t* token);
/**
* 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.
*/
int32_t addOperationAuthTokenIfNeeded(sp<IBinder> token,
std::vector<keymaster_key_param_t>* params);
/**
* Translate a result value to a legacy return value. All keystore errors are
* preserved and keymaster errors become SYSTEM_ERRORs
*/
int32_t translateResultToLegacyResult(int32_t result);
keymaster_key_param_t* getKeyAlgorithm(keymaster_key_characteristics_t* characteristics);
void addLegacyBeginParams(const String16& name, std::vector<keymaster_key_param_t>& params);
int32_t doLegacySignVerify(const String16& name, const uint8_t* data, size_t length,
uint8_t** out, size_t* outLength, const uint8_t* signature,
size_t signatureLength, keymaster_purpose_t 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.
*/
int32_t upgradeKeyBlob(const String16& name, uid_t targetUid,
const keymaster::AuthorizationSet& params, Blob* blob);
::KeyStore* mKeyStore;
OperationMap mOperationMap;
keymaster::AuthTokenTable mAuthTokenTable;
KeystoreKeymasterEnforcement enforcement_policy;
};
}; // namespace android
#endif // KEYSTORE_KEYSTORE_SERVICE_H_