[PATCH v5 3/4] drivers: tee: sandbox: add rpc test ta emulation

[Igor Opaniuk <igor.opaniuk@foundries.io>]

HI Etienne,

On Thu, Jan 21, 2021 at 9:39 AM Etienne Carriere
<etienne.carriere@linaro.org> wrote:
>
> Hi Igor,
>
> On Wed, 20 Jan 2021 at 18:56, Igor Opaniuk <igor.opaniuk@gmail.com> 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           | 143 +++++++++++++++++++++++++++++++-
> >  include/tee/optee_ta_rpc_test.h |  28 +++++++
> >  4 files changed, 178 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
>
> I think this line should move to drivers/tee/optee/Makefile for consistency.
Well, what we do here is testing TEE supplicant from TEE sandbox driver.
So this is why I pull that bits and pieces from OP-TEE driver, however
OP-TEE driver itself
isn't compiled (CONFIG_OPTEE=n when CONFIG_SANDBOX=y).
I don't either like this idea, but currently that's the only way to add some
RPC test coverage that was requested in v1.

CONFIG_OPTEE_TA_RPC_TEST is currently supposed to be used only
in sandbox setups (for testing RPC call paths with DM tests).
>
>
> >  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..d075701b4e 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 +250,100 @@ 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 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;
> > +
> > +       /* 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;
> > +       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;
> > +       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 bad;
> > +
> > +       fill_i2c_rpc_params(msg_arg, bus_num, chip_addr, op, memref_data);
> > +
> > +       /* Make an RPC call to tee supplicant */
> > +       optee_suppl_cmd(dev, shm, 0);
> > +       res = msg_arg->ret;
> > +
> > +bad:
>
> maye rename to out since not a error only path.

ok, will do
>
> > +       tee_shm_free(shm);
> > +
> > +       if (res)
> > +               return res;
> > +
> > +       return TEE_SUCCESS;
>
> 'return res;' will do the job.

sure, will fix

>
> > +}
> > +#endif /* CONFIG_OPTEE_TA_RPC_TEST */
> >
> >  static const struct ta_entry ta_entries[] = {
> >  #ifdef CONFIG_OPTEE_TA_AVB
> > @@ -223,6 +352,12 @@ 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
>
> Should maybe consider the so-called 'i2c control flags' in the test
> (i.?. 7 or 10 bit i2c address) since these flags are checked in the
> RPC implementation.

Yes, makes sense.

>
> > + * 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
> >



-- 
Best regards - Freundliche Gr?sse - Meilleures salutations

Igor Opaniuk
Embedded Software Engineer
T:  +380 938364067
E: igor.opaniuk at foundries.io
W: www.foundries.io