diff options
Diffstat (limited to 'include/linux/rpmb.h')
| -rw-r--r-- | include/linux/rpmb.h | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/include/linux/rpmb.h b/include/linux/rpmb.h new file mode 100644 index 000000000000..ed3f8e431eff --- /dev/null +++ b/include/linux/rpmb.h @@ -0,0 +1,167 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2015-2019 Intel Corp. All rights reserved + * Copyright (C) 2021-2022 Linaro Ltd + */ +#ifndef __RPMB_H__ +#define __RPMB_H__ + +#include <linux/device.h> +#include <linux/types.h> + +/** + * enum rpmb_type - type of underlying storage technology + * + * @RPMB_TYPE_EMMC : emmc (JESD84-B50.1) + * @RPMB_TYPE_UFS : UFS (JESD220) + * @RPMB_TYPE_NVME : NVM Express + */ +enum rpmb_type { + RPMB_TYPE_EMMC, + RPMB_TYPE_UFS, + RPMB_TYPE_NVME, +}; + +/** + * struct rpmb_descr - RPMB description provided by the underlying block device + * + * @type : block device type + * @route_frames : routes frames to and from the RPMB device + * @dev_id : unique device identifier read from the hardware + * @dev_id_len : length of unique device identifier + * @reliable_wr_count: number of sectors that can be written in one access + * @capacity : capacity of the device in units of 128K + * + * @dev_id is intended to be used as input when deriving the authenticaion key. + */ +struct rpmb_descr { + enum rpmb_type type; + int (*route_frames)(struct device *dev, u8 *req, unsigned int req_len, + u8 *resp, unsigned int resp_len); + u8 *dev_id; + size_t dev_id_len; + u16 reliable_wr_count; + u16 capacity; +}; + +/** + * struct rpmb_dev - device which can support RPMB partition + * + * @dev : device + * @id : device_id + * @list_node : linked list node + * @descr : RPMB description + */ +struct rpmb_dev { + struct device dev; + int id; + struct list_head list_node; + struct rpmb_descr descr; +}; + +#define to_rpmb_dev(x) container_of((x), struct rpmb_dev, dev) + +/** + * struct rpmb_frame - RPMB frame structure for authenticated access + * + * @stuff : stuff bytes, a padding/reserved area of 196 bytes at the + * beginning of the RPMB frame. They don’t carry meaningful + * data but are required to make the frame exactly 512 bytes. + * @key_mac : The authentication key or the message authentication + * code (MAC) depending on the request/response type. + * The MAC will be delivered in the last (or the only) + * block of data. + * @data : Data to be written or read by signed access. + * @nonce : Random number generated by the host for the requests + * and copied to the response by the RPMB engine. + * @write_counter: Counter value for the total amount of the successful + * authenticated data write requests made by the host. + * @addr : Address of the data to be programmed to or read + * from the RPMB. Address is the serial number of + * the accessed block (half sector 256B). + * @block_count : Number of blocks (half sectors, 256B) requested to be + * read/programmed. + * @result : Includes information about the status of the write counter + * (valid, expired) and result of the access made to the RPMB. + * @req_resp : Defines the type of request and response to/from the memory. + * + * The stuff bytes and big-endian properties are modeled to fit to the spec. + */ +struct rpmb_frame { + u8 stuff[196]; + u8 key_mac[32]; + u8 data[256]; + u8 nonce[16]; + __be32 write_counter; + __be16 addr; + __be16 block_count; + __be16 result; + __be16 req_resp; +}; + +#define RPMB_PROGRAM_KEY 0x1 /* Program RPMB Authentication Key */ +#define RPMB_GET_WRITE_COUNTER 0x2 /* Read RPMB write counter */ +#define RPMB_WRITE_DATA 0x3 /* Write data to RPMB partition */ +#define RPMB_READ_DATA 0x4 /* Read data from RPMB partition */ +#define RPMB_RESULT_READ 0x5 /* Read result request (Internal) */ + +#if IS_ENABLED(CONFIG_RPMB) +struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev); +void rpmb_dev_put(struct rpmb_dev *rdev); +struct rpmb_dev *rpmb_dev_find_device(const void *data, + const struct rpmb_dev *start, + int (*match)(struct device *dev, + const void *data)); +int rpmb_interface_register(struct class_interface *intf); +void rpmb_interface_unregister(struct class_interface *intf); +struct rpmb_dev *rpmb_dev_register(struct device *dev, + struct rpmb_descr *descr); +int rpmb_dev_unregister(struct rpmb_dev *rdev); + +int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req, + unsigned int req_len, u8 *resp, unsigned int resp_len); + +#else +static inline struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev) +{ + return NULL; +} + +static inline void rpmb_dev_put(struct rpmb_dev *rdev) { } + +static inline struct rpmb_dev * +rpmb_dev_find_device(const void *data, const struct rpmb_dev *start, + int (*match)(struct device *dev, const void *data)) +{ + return NULL; +} + +static inline int rpmb_interface_register(struct class_interface *intf) +{ + return -EOPNOTSUPP; +} + +static inline void rpmb_interface_unregister(struct class_interface *intf) +{ +} + +static inline struct rpmb_dev * +rpmb_dev_register(struct device *dev, struct rpmb_descr *descr) +{ + return NULL; +} + +static inline int rpmb_dev_unregister(struct rpmb_dev *dev) +{ + return 0; +} + +static inline int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req, + unsigned int req_len, u8 *resp, + unsigned int resp_len) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_RPMB */ + +#endif /* __RPMB_H__ */ |