/* * Copyright (C) 2021 The LineageOS 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 XIAOMI_FINGERPRINT_H #define XIAOMI_FINGERPRINT_H #include #include typedef struct xiaomi_fingerprint_device { /** * Common methods of the fingerprint device. This *must* be the first member * of fingerprint_device as users of this structure will cast a hw_device_t * to fingerprint_device pointer in contexts where it's known * the hw_device_t references a fingerprint_device. */ struct hw_device_t common; /* * Client provided callback function to receive notifications. * Do not set by hand, use the function above instead. */ fingerprint_notify_t notify; /* * Set notification callback: * Registers a user function that would receive notifications from the HAL * The call will block if the HAL state machine is in busy state until HAL * leaves the busy state. * * Function return: 0 if callback function is successfuly registered * or a negative number in case of error, generally from the errno.h set. */ int (*set_notify)(struct xiaomi_fingerprint_device *dev, fingerprint_notify_t notify); /* * Fingerprint pre-enroll enroll request: * Generates a unique token to upper layers to indicate the start of an enrollment transaction. * This token will be wrapped by security for verification and passed to enroll() for * verification before enrollment will be allowed. This is to ensure adding a new fingerprint * template was preceded by some kind of credential confirmation (e.g. device password). * * Function return: 0 if function failed * otherwise, a uint64_t of token */ uint64_t (*pre_enroll)(struct xiaomi_fingerprint_device *dev); /* * Fingerprint enroll request: * Switches the HAL state machine to collect and store a new fingerprint * template. Switches back as soon as enroll is complete * (fingerprint_msg.type == FINGERPRINT_TEMPLATE_ENROLLING && * fingerprint_msg.data.enroll.samples_remaining == 0) * or after timeout_sec seconds. * The fingerprint template will be assigned to the group gid. User has a choice * to supply the gid or set it to 0 in which case a unique group id will be generated. * * Function return: 0 if enrollment process can be successfully started * or a negative number in case of error, generally from the errno.h set. * A notify() function may be called indicating the error condition. */ int (*enroll)(struct xiaomi_fingerprint_device *dev, const hw_auth_token_t *hat, uint32_t gid, uint32_t timeout_sec); /* * Finishes the enroll operation and invalidates the pre_enroll() generated challenge. * This will be called at the end of a multi-finger enrollment session to indicate * that no more fingers will be added. * * Function return: 0 if the request is accepted * or a negative number in case of error, generally from the errno.h set. */ int (*post_enroll)(struct xiaomi_fingerprint_device *dev); /* * get_authenticator_id: * Returns a token associated with the current fingerprint set. This value will * change whenever a new fingerprint is enrolled, thus creating a new fingerprint * set. * * Function return: current authenticator id or 0 if function failed. */ uint64_t (*get_authenticator_id)(struct xiaomi_fingerprint_device *dev); /* * Cancel pending enroll or authenticate, sending FINGERPRINT_ERROR_CANCELED * to all running clients. Switches the HAL state machine back to the idle state. * Unlike enroll_done() doesn't invalidate the pre_enroll() challenge. * * Function return: 0 if cancel request is accepted * or a negative number in case of error, generally from the errno.h set. */ int (*cancel)(struct xiaomi_fingerprint_device *dev); /* * Enumerate all the fingerprint templates found in the directory set by * set_active_group() * For each template found a notify() will be called with: * fingerprint_msg.type == FINGERPRINT_TEMPLATE_ENUMERATED * fingerprint_msg.data.enumerated.finger indicating a template id * fingerprint_msg.data.enumerated.remaining_templates indicating how many more * enumeration messages to expect. * Note: If there are no fingerprints, then this should return 0 and the first fingerprint * enumerated should have fingerid=0 and remaining=0 * Function return: 0 if enumerate request is accepted * or a negative number in case of error, generally from the errno.h set. */ int (*enumerate)(struct xiaomi_fingerprint_device *dev); /* * Fingerprint remove request: * Deletes a fingerprint template. * Works only within the path set by set_active_group(). * The fid parameter can be used as a widcard: * * fid == 0 -- delete all the templates in the group. * * fid != 0 -- delete this specific template from the group. * For each template found a notify() will be called with: * fingerprint_msg.type == FINGERPRINT_TEMPLATE_REMOVED * fingerprint_msg.data.removed.finger indicating a template id deleted * fingerprint_msg.data.removed.remaining_templates indicating how many more * templates will be deleted by this operation. * * Function return: 0 if fingerprint template(s) can be successfully deleted * or a negative number in case of error, generally from the errno.h set. */ int (*remove)(struct xiaomi_fingerprint_device *dev, uint32_t gid, uint32_t fid); /* * Restricts the HAL operation to a set of fingerprints belonging to a * group provided. * The caller must provide a path to a storage location within the user's * data directory. * * Function return: 0 on success * or a negative number in case of error, generally from the errno.h set. */ int (*set_active_group)(struct xiaomi_fingerprint_device *dev, uint32_t gid, const char *store_path); /* * Authenticates an operation identifed by operation_id * * Function return: 0 on success * or a negative number in case of error, generally from the errno.h set. */ int (*authenticate)(struct xiaomi_fingerprint_device *dev, uint64_t operation_id, uint32_t gid); /* * Call a Xiaomi fingerprint extension command. */ int (*extCmd)(struct xiaomi_fingerprint_device *dev, int32_t cmd, int32_t param); /* * Reserved for backward binary compatibility */ void *reserved[4]; } xiaomi_fingerprint_device_t; #endif // XIAOMI_FINGERPRINT_H