[v6,3/4] drivers: tee: sandbox: add rpc test ta emulation

From: Igor Opaniuk <igor.opaniuk@foundries.io>

This adds support for RPC test trusted application emulation, which
permits to test reverse RPC calls to TEE supplicant. Currently it covers
requests to the I2C bus from TEE.

Signed-off-by: Igor Opaniuk <igor.opaniuk@foundries.io>
Reviewed-by: Simon Glass <sjg@chromium.org>
---

(no changes since v1)

 drivers/tee/Makefile            |   2 +
 drivers/tee/optee/Kconfig       |   9 ++
 drivers/tee/sandbox.c           | 142 +++++++++++++++++++++++++++++++-
 include/tee/optee_ta_rpc_test.h |  28 +++++++
 4 files changed, 177 insertions(+), 4 deletions(-)
 create mode 100644 include/tee/optee_ta_rpc_test.h

On Fri, Jan 22, 2021 at 12:51 PM Igor Opaniuk <igor.opaniuk@foundries.io> wrote:
>
> From: Igor Opaniuk <igor.opaniuk@foundries.io>
>
> This adds support for RPC test trusted application emulation, which
> permits to test reverse RPC calls to TEE supplicant. Currently it covers
> requests to the I2C bus from TEE.
>
> Signed-off-by: Igor Opaniuk <igor.opaniuk@foundries.io>
> Reviewed-by: Simon Glass <sjg@chromium.org>
> ---

Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>

Thanks,
Jens

Hi Igor,

With comment addressed:
Acked-by: Etienne Carriere <etienne.carriere@linaro.org>

Cheers,
Etienne

On Fri, 22 Jan 2021 at 12:51, Igor Opaniuk <igor.opaniuk@foundries.io> wrote:
>
> From: Igor Opaniuk <igor.opaniuk@foundries.io>
>
> This adds support for RPC test trusted application emulation, which
> permits to test reverse RPC calls to TEE supplicant. Currently it covers
> requests to the I2C bus from TEE.
>
> Signed-off-by: Igor Opaniuk <igor.opaniuk@foundries.io>
> Reviewed-by: Simon Glass <sjg@chromium.org>
> ---
>
> (no changes since v1)
>
>  drivers/tee/Makefile            |   2 +
>  drivers/tee/optee/Kconfig       |   9 ++
>  drivers/tee/sandbox.c           | 142 +++++++++++++++++++++++++++++++-
>  include/tee/optee_ta_rpc_test.h |  28 +++++++
>  4 files changed, 177 insertions(+), 4 deletions(-)
>  create mode 100644 include/tee/optee_ta_rpc_test.h
>
> diff --git a/drivers/tee/Makefile b/drivers/tee/Makefile
> index 5c8ffdbce8..ff844195ae 100644
> --- a/drivers/tee/Makefile
> +++ b/drivers/tee/Makefile
> @@ -2,5 +2,7 @@
>
>  obj-y += tee-uclass.o
>  obj-$(CONFIG_SANDBOX) += sandbox.o
> +obj-$(CONFIG_OPTEE_TA_RPC_TEST) += optee/supplicant.o
> +obj-$(CONFIG_OPTEE_TA_RPC_TEST) += optee/i2c.o
>  obj-$(CONFIG_OPTEE) += optee/
>  obj-y += broadcom/
> diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig
> index d489834df9..65622f30b1 100644
> --- a/drivers/tee/optee/Kconfig
> +++ b/drivers/tee/optee/Kconfig
> @@ -22,6 +22,15 @@ config OPTEE_TA_AVB
>           The TA can support the "avb" subcommands "read_rb", "write"rb"
>           and "is_unlocked".
>
> +config OPTEE_TA_RPC_TEST
> +       bool "Support RPC TEST TA"
> +       depends on SANDBOX_TEE
> +       default y
> +       help
> +         Enables support for RPC test trusted application emulation, which
> +         permits to test reverse RPC calls to TEE supplicant. Should
> +         be used only in sandbox env.
> +
>  endmenu
>
>  endif
> diff --git a/drivers/tee/sandbox.c b/drivers/tee/sandbox.c
> index e1ba027fd6..3a1d34d6fc 100644
> --- a/drivers/tee/sandbox.c
> +++ b/drivers/tee/sandbox.c
> @@ -7,11 +7,15 @@
>  #include <sandboxtee.h>
>  #include <tee.h>
>  #include <tee/optee_ta_avb.h>
> +#include <tee/optee_ta_rpc_test.h>
> +
> +#include "optee/optee_msg.h"
> +#include "optee/optee_private.h"
>
>  /*
>   * The sandbox tee driver tries to emulate a generic Trusted Exectution
> - * Environment (TEE) with the Trusted Application (TA) OPTEE_TA_AVB
> - * available.
> + * Environment (TEE) with the Trusted Applications (TA) OPTEE_TA_AVB and
> + * OPTEE_TA_RPC_TEST available.
>   */
>
>  static const u32 pstorage_max = 16;
> @@ -32,7 +36,38 @@ struct ta_entry {
>                            struct tee_param *params);
>  };
>
> -#ifdef CONFIG_OPTEE_TA_AVB
> +static int get_msg_arg(struct udevice *dev, uint num_params,
> +                      struct tee_shm **shmp, struct optee_msg_arg **msg_arg)
> +{
> +       int rc;
> +       struct optee_msg_arg *ma;
> +
> +       rc = __tee_shm_add(dev, OPTEE_MSG_NONCONTIG_PAGE_SIZE, NULL,
> +                          OPTEE_MSG_GET_ARG_SIZE(num_params), TEE_SHM_ALLOC,
> +                          shmp);
> +       if (rc)
> +               return rc;
> +
> +       ma = (*shmp)->addr;
> +       memset(ma, 0, OPTEE_MSG_GET_ARG_SIZE(num_params));
> +       ma->num_params = num_params;
> +       *msg_arg = ma;
> +
> +       return 0;
> +}
> +
> +void *optee_alloc_and_init_page_list(void *buf, ulong len,
> +                                    u64 *phys_buf_ptr)
> +{
> +       /*
> +        * An empty stub is added just to fix linking issues.
> +        * This function isn't supposed to be called in sandbox
> +        * setup, otherwise replace this with a proper
> +        * implementation from optee/core.c
> +        */
> +       return NULL;
> +}
> +
>  static u32 get_attr(uint n, uint num_params, struct tee_param *params)
>  {
>         if (n >= num_params)
> @@ -63,6 +98,7 @@ bad_params:
>         return TEE_ERROR_BAD_PARAMETERS;
>  }
>
> +#ifdef CONFIG_OPTEE_TA_AVB
>  static u32 ta_avb_open_session(struct udevice *dev, uint num_params,
>                                struct tee_param *params)
>  {
> @@ -214,7 +250,99 @@ static u32 ta_avb_invoke_func(struct udevice *dev, u32 func, uint num_params,
>                 return TEE_ERROR_NOT_SUPPORTED;
>         }
>  }
> -#endif /*OPTEE_TA_AVB*/
> +#endif /* OPTEE_TA_AVB */
> +
> +#ifdef CONFIG_OPTEE_TA_RPC_TEST
> +static u32 ta_rpc_test_open_session(struct udevice *dev, uint num_params,
> +                                   struct tee_param *params)
> +{
> +       /*
> +        * We don't expect additional parameters when opening a session to
> +        * this TA.
> +        */
> +       return check_params(TEE_PARAM_ATTR_TYPE_NONE, TEE_PARAM_ATTR_TYPE_NONE,
> +                           TEE_PARAM_ATTR_TYPE_NONE, TEE_PARAM_ATTR_TYPE_NONE,
> +                           num_params, params);
> +}
> +
> +static void fill_i2c_rpc_params(struct optee_msg_arg *msg_arg, u64 bus_num,
> +                               u64 chip_addr, u64 xfer_flags, u64 op,
> +                               struct tee_param_memref memref)
> +{
> +       msg_arg->params[0].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
> +       msg_arg->params[1].attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT;
> +       msg_arg->params[2].attr = OPTEE_MSG_ATTR_TYPE_RMEM_INOUT;
> +       msg_arg->params[3].attr = OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT;
> +
> +       /* trigger I2C services of TEE supplicant */
> +       msg_arg->cmd = OPTEE_MSG_RPC_CMD_I2C_TRANSFER;
> +
> +       msg_arg->params[0].u.value.a = op;
> +       msg_arg->params[0].u.value.b = bus_num;
> +       msg_arg->params[0].u.value.c = chip_addr;
> +       msg_arg->params[1].u.value.a = xfer_flags;
> +
> +       /* buffer to read/write data */
> +       msg_arg->params[2].u.rmem.shm_ref = (ulong)memref.shm;
> +       msg_arg->params[2].u.rmem.size = memref.size;
> +       msg_arg->params[2].u.rmem.offs = memref.shm_offs;
> +
> +       msg_arg->num_params = 4;
> +}
> +
> +static u32 ta_rpc_test_invoke_func(struct udevice *dev, u32 func,
> +                                  uint num_params,
> +                                  struct tee_param *params)
> +{
> +       struct tee_shm *shm;
> +       struct tee_param_memref memref_data;
> +       struct optee_msg_arg *msg_arg;
> +       int chip_addr, bus_num, op, xfer_flags;
> +       int res;
> +
> +       res = check_params(TEE_PARAM_ATTR_TYPE_VALUE_INPUT,
> +                          TEE_PARAM_ATTR_TYPE_MEMREF_INOUT,
> +                          TEE_PARAM_ATTR_TYPE_NONE,
> +                          TEE_PARAM_ATTR_TYPE_NONE,
> +                          num_params, params);
> +       if (res)
> +               return TEE_ERROR_BAD_PARAMETERS;
> +
> +       bus_num = params[0].u.value.a;
> +       chip_addr = params[0].u.value.b;
> +       xfer_flags = params[0].u.value.c;
> +       memref_data = params[1].u.memref;
> +
> +       switch (func) {
> +       case TA_RPC_TEST_CMD_I2C_READ:
> +               op = OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD;
> +               break;
> +       case TA_RPC_TEST_CMD_I2C_WRITE:
> +               op = OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR;
> +               break;
> +       default:
> +               return TEE_ERROR_NOT_SUPPORTED;
> +       }
> +
> +       /*
> +        * Fill params for an RPC call to tee supplicant
> +        */
> +       res = get_msg_arg(dev, 4, &shm, &msg_arg);
> +       if (res)
> +               goto out;
> +
> +       fill_i2c_rpc_params(msg_arg, bus_num, chip_addr, xfer_flags, op,
> +                           memref_data);
> +
> +       /* Make an RPC call to tee supplicant */
> +       optee_suppl_cmd(dev, shm, 0);
> +       res = msg_arg->ret;
> +out:
> +       tee_shm_free(shm);
> +
> +       return res;
> +}
> +#endif /* CONFIG_OPTEE_TA_RPC_TEST */
>
>  static const struct ta_entry ta_entries[] = {
>  #ifdef CONFIG_OPTEE_TA_AVB
> @@ -223,6 +351,12 @@ static const struct ta_entry ta_entries[] = {
>           .invoke_func = ta_avb_invoke_func,
>         },
>  #endif
> +#ifdef CONFIG_OPTEE_TA_RPC_TEST
> +       { .uuid = TA_RPC_TEST_UUID,
> +         .open_session = ta_rpc_test_open_session,
> +         .invoke_func = ta_rpc_test_invoke_func,
> +       },
> +#endif
>  };
>
>  static void sandbox_tee_get_version(struct udevice *dev,
> diff --git a/include/tee/optee_ta_rpc_test.h b/include/tee/optee_ta_rpc_test.h
> new file mode 100644
> index 0000000000..cae2fb04b4
> --- /dev/null
> +++ b/include/tee/optee_ta_rpc_test.h
> @@ -0,0 +1,28 @@
> +/* SPDX-License-Identifier: BSD-2-Clause */
> +/* Copyright (c) 2020 Foundries Ltd */
> +
> +#ifndef __TA_RPC_TEST_H
> +#define __TA_RPC_TEST_H
> +
> +#define TA_RPC_TEST_UUID { 0x48420575, 0x96ca, 0x401a, \
> +                     { 0x89, 0x91, 0x1e, 0xfd, 0xce, 0xbd, 0x7d, 0x04 } }
> +
> +/*
> + * Does a reverse RPC call for I2C read
> + *
> + * in          params[0].value.a:      bus number
> + * in          params[0].value.b:      chip address

add
 * in params[0].value.c:      control flags

> + * inout       params[1].u.memref:     buffer to read data
> + */
> +#define TA_RPC_TEST_CMD_I2C_READ       0
> +
> +/*
> + * Does a reverse RPC call for I2C write
> + *
> + * in          params[0].value.a:      bus number
> + * in          params[0].value.b:      chip address
> + * inout       params[1].u.memref:     buffer with data to write
> + */
> +#define TA_RPC_TEST_CMD_I2C_WRITE      1
> +
> +#endif /* __TA_RPC_TEST_H */
> --
> 2.25.1
>