1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright (C) 2015-2019 Intel Corp. All rights reserved
4 * Copyright (C) 2021-2022 Linaro Ltd
5 */
6#ifndef __RPMB_H__
7#define __RPMB_H__
8
9#include <linux/device.h>
10#include <linux/types.h>
11
12/**
13 * enum rpmb_type - type of underlying storage technology
14 *
15 * @RPMB_TYPE_EMMC : emmc (JESD84-B50.1)
16 * @RPMB_TYPE_UFS : UFS (JESD220)
17 * @RPMB_TYPE_NVME : NVM Express
18 */
19enum rpmb_type {
20 RPMB_TYPE_EMMC,
21 RPMB_TYPE_UFS,
22 RPMB_TYPE_NVME,
23};
24
25/**
26 * struct rpmb_descr - RPMB description provided by the underlying block device
27 *
28 * @type : block device type
29 * @route_frames : routes frames to and from the RPMB device
30 * @dev_id : unique device identifier read from the hardware
31 * @dev_id_len : length of unique device identifier
32 * @reliable_wr_count: number of sectors that can be written in one access
33 * @capacity : capacity of the device in units of 128K
34 *
35 * @dev_id is intended to be used as input when deriving the authenticaion key.
36 */
37struct rpmb_descr {
38 enum rpmb_type type;
39 int (*route_frames)(struct device *dev, u8 *req, unsigned int req_len,
40 u8 *resp, unsigned int resp_len);
41 u8 *dev_id;
42 size_t dev_id_len;
43 u16 reliable_wr_count;
44 u16 capacity;
45};
46
47/**
48 * struct rpmb_dev - device which can support RPMB partition
49 *
50 * @dev : device
51 * @id : device_id
52 * @list_node : linked list node
53 * @descr : RPMB description
54 */
55struct rpmb_dev {
56 struct device dev;
57 int id;
58 struct list_head list_node;
59 struct rpmb_descr descr;
60};
61
62#define to_rpmb_dev(x) container_of((x), struct rpmb_dev, dev)
63
64/**
65 * struct rpmb_frame - RPMB frame structure for authenticated access
66 *
67 * @stuff : stuff bytes, a padding/reserved area of 196 bytes at the
68 * beginning of the RPMB frame. They don’t carry meaningful
69 * data but are required to make the frame exactly 512 bytes.
70 * @key_mac : The authentication key or the message authentication
71 * code (MAC) depending on the request/response type.
72 * The MAC will be delivered in the last (or the only)
73 * block of data.
74 * @data : Data to be written or read by signed access.
75 * @nonce : Random number generated by the host for the requests
76 * and copied to the response by the RPMB engine.
77 * @write_counter: Counter value for the total amount of the successful
78 * authenticated data write requests made by the host.
79 * @addr : Address of the data to be programmed to or read
80 * from the RPMB. Address is the serial number of
81 * the accessed block (half sector 256B).
82 * @block_count : Number of blocks (half sectors, 256B) requested to be
83 * read/programmed.
84 * @result : Includes information about the status of the write counter
85 * (valid, expired) and result of the access made to the RPMB.
86 * @req_resp : Defines the type of request and response to/from the memory.
87 *
88 * The stuff bytes and big-endian properties are modeled to fit to the spec.
89 */
90struct rpmb_frame {
91 u8 stuff[196];
92 u8 key_mac[32];
93 u8 data[256];
94 u8 nonce[16];
95 __be32 write_counter;
96 __be16 addr;
97 __be16 block_count;
98 __be16 result;
99 __be16 req_resp;
100};
101
102#define RPMB_PROGRAM_KEY 0x1 /* Program RPMB Authentication Key */
103#define RPMB_GET_WRITE_COUNTER 0x2 /* Read RPMB write counter */
104#define RPMB_WRITE_DATA 0x3 /* Write data to RPMB partition */
105#define RPMB_READ_DATA 0x4 /* Read data from RPMB partition */
106#define RPMB_RESULT_READ 0x5 /* Read result request (Internal) */
107
108#if IS_ENABLED(CONFIG_RPMB)
109struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev);
110void rpmb_dev_put(struct rpmb_dev *rdev);
111struct rpmb_dev *rpmb_dev_find_device(const void *data,
112 const struct rpmb_dev *start,
113 int (*match)(struct device *dev,
114 const void *data));
115int rpmb_interface_register(struct class_interface *intf);
116void rpmb_interface_unregister(struct class_interface *intf);
117struct rpmb_dev *rpmb_dev_register(struct device *dev,
118 struct rpmb_descr *descr);
119int rpmb_dev_unregister(struct rpmb_dev *rdev);
120
121int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req,
122 unsigned int req_len, u8 *resp, unsigned int resp_len);
123
124#else
125static inline struct rpmb_dev *rpmb_dev_get(struct rpmb_dev *rdev)
126{
127 return NULL;
128}
129
130static inline void rpmb_dev_put(struct rpmb_dev *rdev) { }
131
132static inline struct rpmb_dev *
133rpmb_dev_find_device(const void *data, const struct rpmb_dev *start,
134 int (*match)(struct device *dev, const void *data))
135{
136 return NULL;
137}
138
139static inline int rpmb_interface_register(struct class_interface *intf)
140{
141 return -EOPNOTSUPP;
142}
143
144static inline void rpmb_interface_unregister(struct class_interface *intf)
145{
146}
147
148static inline struct rpmb_dev *
149rpmb_dev_register(struct device *dev, struct rpmb_descr *descr)
150{
151 return NULL;
152}
153
154static inline int rpmb_dev_unregister(struct rpmb_dev *dev)
155{
156 return 0;
157}
158
159static inline int rpmb_route_frames(struct rpmb_dev *rdev, u8 *req,
160 unsigned int req_len, u8 *resp,
161 unsigned int resp_len)
162{
163 return -EOPNOTSUPP;
164}
165#endif /* CONFIG_RPMB */
166
167#endif /* __RPMB_H__ */
168

source code of linux/include/linux/rpmb.h