/*
 * Copyright (c) 2015-2016, Linaro Limited
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef __TEE_H
#define __TEE_H

#include <linux/ioctl.h>
#include <linux/types.h>

/*
 * This file describes the API provided by a TEE driver to user space.
 *
 * Each TEE driver defines a TEE specific protocol which is used for the
 * data passed back and forth using TEE_IOC_CMD.
 */

/* Helpers to make the ioctl defines */
#define TEE_IOC_MAGIC   0xa4
#define TEE_IOC_BASE    0

/* Flags relating to shared memory */
#define TEE_IOCTL_SHM_MAPPED    0x1     /* memory mapped in normal world */
#define TEE_IOCTL_SHM_DMA_BUF   0x2     /* dma-buf handle on shared memory */

#define TEE_MAX_ARG_SIZE        1024

#define TEE_GEN_CAP_GP          (1 << 0)/* GlobalPlatform compliant TEE */
#define TEE_GEN_CAP_PRIVILEGED  (1 << 1)/* Privileged device (for supplicant) */
#define TEE_GEN_CAP_REG_MEM     (1 << 2)/* Supports registering shared memory */
#define TEE_GEN_CAP_MEMREF_NULL (1 << 3)/* NULL MemRef support */

#define TEE_MEMREF_NULL         (__u64)(-1) /* NULL MemRef Buffer */

/*
 * TEE Implementation ID
 */
#define TEE_IMPL_ID_OPTEE       1
#define TEE_IMPL_ID_AMDTEE      2

/*
 * OP-TEE specific capabilities
 */
#define TEE_OPTEE_CAP_TZ        (1 << 0)

/**
 * struct tee_ioctl_version_data - TEE version
 * @impl_id:    [out] TEE implementation id
 * @impl_caps:  [out] Implementation specific capabilities
 * @gen_caps:   [out] Generic capabilities, defined by TEE_GEN_CAPS_* above
 *
 * Identifies the TEE implementation, @impl_id is one of TEE_IMPL_ID_* above.
 * @impl_caps is implementation specific, for example TEE_OPTEE_CAP_*
 * is valid when @impl_id == TEE_IMPL_ID_OPTEE.
 */
struct tee_ioctl_version_data {
        __u32 impl_id;
        __u32 impl_caps;
        __u32 gen_caps;
};

/**
 * TEE_IOC_VERSION - query version of TEE
 *
 * Takes a tee_ioctl_version_data struct and returns with the TEE version
 * data filled in.
 */
#define TEE_IOC_VERSION         _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 0, \
                                     struct tee_ioctl_version_data)

/**
 * struct tee_ioctl_shm_alloc_data - Shared memory allocate argument
 * @size:       [in/out] Size of shared memory to allocate
 * @flags:      [in/out] Flags to/from allocation.
 * @id:         [out] Identifier of the shared memory
 *
 * The flags field should currently be zero as input. Updated by the call
 * with actual flags as defined by TEE_IOCTL_SHM_* above.
 * This structure is used as argument for TEE_IOC_SHM_ALLOC below.
 */
struct tee_ioctl_shm_alloc_data {
        __u64 size;
        __u32 flags;
        __s32 id;
};

/**
 * TEE_IOC_SHM_ALLOC - allocate shared memory
 *
 * Allocates shared memory between the user space process and secure OS.
 *
 * Returns a file descriptor on success or < 0 on failure
 *
 * The returned file descriptor is used to map the shared memory into user
 * space. The shared memory is freed when the descriptor is closed and the
 * memory is unmapped.
 */
#define TEE_IOC_SHM_ALLOC       _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 1, \
                                     struct tee_ioctl_shm_alloc_data)

/**
 * struct tee_ioctl_buf_data - Variable sized buffer
 * @buf_ptr:    [in] A __user pointer to a buffer
 * @buf_len:    [in] Length of the buffer above
 *
 * Used as argument for TEE_IOC_OPEN_SESSION, TEE_IOC_INVOKE,
 * TEE_IOC_SUPPL_RECV, and TEE_IOC_SUPPL_SEND below.
 */
struct tee_ioctl_buf_data {
        __u64 buf_ptr;
        __u64 buf_len;
};

/*
 * Attributes for struct tee_ioctl_param, selects field in the union
 */
#define TEE_IOCTL_PARAM_ATTR_TYPE_NONE          0       /* parameter not used */

/*
 * These defines value parameters (struct tee_ioctl_param_value)
 */
#define TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT   1
#define TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT  2
#define TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT   3       /* input and output */

/*
 * These defines shared memory reference parameters (struct
 * tee_ioctl_param_memref)
 */
#define TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT  5
#define TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT 6
#define TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT  7       /* input and output */

/*
 * Mask for the type part of the attribute, leaves room for more types
 */
#define TEE_IOCTL_PARAM_ATTR_TYPE_MASK          0xff

/* Meta parameter carrying extra information about the message. */
#define TEE_IOCTL_PARAM_ATTR_META               0x100

/* Mask of all known attr bits */
#define TEE_IOCTL_PARAM_ATTR_MASK \
        (TEE_IOCTL_PARAM_ATTR_TYPE_MASK | TEE_IOCTL_PARAM_ATTR_META)

/*
 * Matches TEEC_LOGIN_* in GP TEE Client API
 * Are only defined for GP compliant TEEs
 */
#define TEE_IOCTL_LOGIN_PUBLIC                  0
#define TEE_IOCTL_LOGIN_USER                    1
#define TEE_IOCTL_LOGIN_GROUP                   2
#define TEE_IOCTL_LOGIN_APPLICATION             4
#define TEE_IOCTL_LOGIN_USER_APPLICATION        5
#define TEE_IOCTL_LOGIN_GROUP_APPLICATION       6
/*
 * Disallow user-space to use GP implementation specific login
 * method range (0x80000000 - 0xBFFFFFFF). This range is rather
 * being reserved for REE kernel clients or TEE implementation.
 */
#define TEE_IOCTL_LOGIN_REE_KERNEL_MIN          0x80000000
#define TEE_IOCTL_LOGIN_REE_KERNEL_MAX          0xBFFFFFFF
/* Private login method for REE kernel clients */
#define TEE_IOCTL_LOGIN_REE_KERNEL              0x80000000

/**
 * struct tee_ioctl_param - parameter
 * @attr: attributes
 * @a: if a memref, offset into the shared memory object, else a value parameter
 * @b: if a memref, size of the buffer, else a value parameter
 * @c: if a memref, shared memory identifier, else a value parameter
 *
 * @attr & TEE_PARAM_ATTR_TYPE_MASK indicates if memref or value is used in
 * the union. TEE_PARAM_ATTR_TYPE_VALUE_* indicates value and
 * TEE_PARAM_ATTR_TYPE_MEMREF_* indicates memref. TEE_PARAM_ATTR_TYPE_NONE
 * indicates that none of the members are used.
 *
 * Shared memory is allocated with TEE_IOC_SHM_ALLOC which returns an
 * identifier representing the shared memory object. A memref can reference
 * a part of a shared memory by specifying an offset (@a) and size (@b) of
 * the object. To supply the entire shared memory object set the offset
 * (@a) to 0 and size (@b) to the previously returned size of the object.
 *
 * A client may need to present a NULL pointer in the argument
 * passed to a trusted application in the TEE.
 * This is also a requirement in GlobalPlatform Client API v1.0c
 * (section 3.2.5 memory references), which can be found at
 * http://www.globalplatform.org/specificationsdevice.asp
 *
 * If a NULL pointer is passed to a TA in the TEE, the (@c)
 * IOCTL parameters value must be set to TEE_MEMREF_NULL indicating a NULL
 * memory reference.
 */
struct tee_ioctl_param {
        __u64 attr;
        __u64 a;
        __u64 b;
        __u64 c;
};

#define TEE_IOCTL_UUID_LEN              16

/**
 * struct tee_ioctl_open_session_arg - Open session argument
 * @uuid:       [in] UUID of the Trusted Application
 * @clnt_uuid:  [in] UUID of client
 * @clnt_login: [in] Login class of client, TEE_IOCTL_LOGIN_* above
 * @cancel_id:  [in] Cancellation id, a unique value to identify this request
 * @session:    [out] Session id
 * @ret:        [out] return value
 * @ret_origin  [out] origin of the return value
 * @num_params  [in] number of parameters following this struct
 */
struct tee_ioctl_open_session_arg {
        __u8 uuid[TEE_IOCTL_UUID_LEN];
        __u8 clnt_uuid[TEE_IOCTL_UUID_LEN];
        __u32 clnt_login;
        __u32 cancel_id;
        __u32 session;
        __u32 ret;
        __u32 ret_origin;
        __u32 num_params;
        /* num_params tells the actual number of element in params */
        struct tee_ioctl_param params[];
};

/**
 * TEE_IOC_OPEN_SESSION - opens a session to a Trusted Application
 *
 * Takes a struct tee_ioctl_buf_data which contains a struct
 * tee_ioctl_open_session_arg followed by any array of struct
 * tee_ioctl_param
 */
#define TEE_IOC_OPEN_SESSION    _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 2, \
                                     struct tee_ioctl_buf_data)

/**
 * struct tee_ioctl_invoke_func_arg - Invokes a function in a Trusted
 * Application
 * @func:       [in] Trusted Application function, specific to the TA
 * @session:    [in] Session id
 * @cancel_id:  [in] Cancellation id, a unique value to identify this request
 * @ret:        [out] return value
 * @ret_origin  [out] origin of the return value
 * @num_params  [in] number of parameters following this struct
 */
struct tee_ioctl_invoke_arg {
        __u32 func;
        __u32 session;
        __u32 cancel_id;
        __u32 ret;
        __u32 ret_origin;
        __u32 num_params;
        /* num_params tells the actual number of element in params */
        struct tee_ioctl_param params[];
};

/**
 * TEE_IOC_INVOKE - Invokes a function in a Trusted Application
 *
 * Takes a struct tee_ioctl_buf_data which contains a struct
 * tee_invoke_func_arg followed by any array of struct tee_param
 */
#define TEE_IOC_INVOKE          _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 3, \
                                     struct tee_ioctl_buf_data)

/**
 * struct tee_ioctl_cancel_arg - Cancels an open session or invoke ioctl
 * @cancel_id:  [in] Cancellation id, a unique value to identify this request
 * @session:    [in] Session id, if the session is opened, else set to 0
 */
struct tee_ioctl_cancel_arg {
        __u32 cancel_id;
        __u32 session;
};

/**
 * TEE_IOC_CANCEL - Cancels an open session or invoke
 */
#define TEE_IOC_CANCEL          _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 4, \
                                     struct tee_ioctl_cancel_arg)

/**
 * struct tee_ioctl_close_session_arg - Closes an open session
 * @session:    [in] Session id
 */
struct tee_ioctl_close_session_arg {
        __u32 session;
};

/**
 * TEE_IOC_CLOSE_SESSION - Closes a session
 */
#define TEE_IOC_CLOSE_SESSION   _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 5, \
                                     struct tee_ioctl_close_session_arg)

/**
 * struct tee_iocl_supp_recv_arg - Receive a request for a supplicant function
 * @func:       [in] supplicant function
 * @num_params  [in/out] number of parameters following this struct
 *
 * @num_params is the number of params that tee-supplicant has room to
 * receive when input, @num_params is the number of actual params
 * tee-supplicant receives when output.
 */
struct tee_iocl_supp_recv_arg {
        __u32 func;
        __u32 num_params;
        /* num_params tells the actual number of element in params */
        struct tee_ioctl_param params[];
};

/**
 * TEE_IOC_SUPPL_RECV - Receive a request for a supplicant function
 *
 * Takes a struct tee_ioctl_buf_data which contains a struct
 * tee_iocl_supp_recv_arg followed by any array of struct tee_param
 */
#define TEE_IOC_SUPPL_RECV      _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 6, \
                                     struct tee_ioctl_buf_data)

/**
 * struct tee_iocl_supp_send_arg - Send a response to a received request
 * @ret:        [out] return value
 * @num_params  [in] number of parameters following this struct
 */
struct tee_iocl_supp_send_arg {
        __u32 ret;
        __u32 num_params;
        /* num_params tells the actual number of element in params */
        struct tee_ioctl_param params[];
};

/**
 * TEE_IOC_SUPPL_SEND - Send a response to a received request
 *
 * Takes a struct tee_ioctl_buf_data which contains a struct
 * tee_iocl_supp_send_arg followed by any array of struct tee_param
 */
#define TEE_IOC_SUPPL_SEND      _IOR(TEE_IOC_MAGIC, TEE_IOC_BASE + 7, \
                                     struct tee_ioctl_buf_data)

/**
 * struct tee_ioctl_shm_register_data - Shared memory register argument
 * @addr:      [in] Start address of shared memory to register
 * @length:    [in/out] Length of shared memory to register
 * @flags:     [in/out] Flags to/from registration.
 * @id:                [out] Identifier of the shared memory
 *
 * The flags field should currently be zero as input. Updated by the call
 * with actual flags as defined by TEE_IOCTL_SHM_* above.
 * This structure is used as argument for TEE_IOC_SHM_REGISTER below.
 */
struct tee_ioctl_shm_register_data {
        __u64 addr;
        __u64 length;
        __u32 flags;
        __s32 id;
};

/**
 * TEE_IOC_SHM_REGISTER - Register shared memory argument
 *
 * Registers shared memory between the user space process and secure OS.
 *
 * Returns a file descriptor on success or < 0 on failure
 *
 * The shared memory is unregisterred when the descriptor is closed.
 */
#define TEE_IOC_SHM_REGISTER   _IOWR(TEE_IOC_MAGIC, TEE_IOC_BASE + 9, \
                                     struct tee_ioctl_shm_register_data)
/*
 * Five syscalls are used when communicating with the TEE driver.
 * open(): opens the device associated with the driver
 * ioctl(): as described above operating on the file descriptor from open()
 * close(): two cases
 *   - closes the device file descriptor
 *   - closes a file descriptor connected to allocated shared memory
 * mmap(): maps shared memory into user space using information from struct
 *         tee_ioctl_shm_alloc_data
 * munmap(): unmaps previously shared memory
 */

#endif /*__TEE_H*/