On 08/06/20, Jens Wiklander wrote: > On Mon, Jun 01, 2020 at 09:24:46AM +0200, Jorge Ramirez-Ortiz, Foundries > wrote: > > On 01/06/20, Sumit Garg wrote: > > > Hi Jorge, > > > > hey > > > > > > > > On Mon, 1 Jun 2020 at 04:41, Jorge Ramirez-Ortiz <jo...@foundries.io> > > > wrote: > > > > > > > > Some secure elements like NXP's SE050 sit on I2C buses. For OP-TEE to > > > > control this type of cryptographic devices it needs coordinated access > > > > to the bus, so collisions and RUNTIME_PM dont get in the way. > > > > > > > > This trampoline driver allow OP-TEE to access them. > > > > > > > > > > This sounds like an interesting use-case but I would like to > > > understand how secure is this communication interface with the secure > > > element? Like in the case of RPMB, secure world data is encrypted > > > which flows via tee-supplicant to RPMB device. > > > > right, the data in the buffer should be encrypted in both directions > > (in the case of the SE050 [1] we have the option to operate with or > > without encryption which is what I am doing during development > > [2]). > > > > But ultimately -before any product can be shipped- all comms must be > > encrypted: this means that when OP-TEE uses the SE050 for crypto, it > > must encrypt the data on write and decrypt what is comming from the > > SE050 on read. I am now looking into how to enable this. > > > > [1] https://www.nxp.com/docs/en/data-sheet/SE050-DATASHEET.pdf > > [2] https://github.com/ldts/optee_os/commits/se050 > This link doesn't work.
apologies, I updated the SDK release to 2.14 (latest) please use the following: https://github.com/ldts/optee_os/commits/se050.2.14 > > > > > > > > > -Sumit > > > > > > > Signed-off-by: Jorge Ramirez-Ortiz <jo...@foundries.io> > > > > --- > > > > drivers/tee/optee/optee_msg.h | 18 +++++++++++ > > > > drivers/tee/optee/rpc.c | 57 +++++++++++++++++++++++++++++++++++ > > > > 2 files changed, 75 insertions(+) > > > > > > > > diff --git a/drivers/tee/optee/optee_msg.h > > > > b/drivers/tee/optee/optee_msg.h > > > > index 795bc19ae17a..b6cc964fdeea 100644 > > > > --- a/drivers/tee/optee/optee_msg.h > > > > +++ b/drivers/tee/optee/optee_msg.h > > > > @@ -419,4 +419,22 @@ struct optee_msg_arg { > > > > */ > > > > #define OPTEE_MSG_RPC_CMD_SHM_FREE 7 > > > > > > > > +/* > > > > + * Access a device on an i2c bus > > > > + * > > > > + * [in] param[0].u.value.a mode: RD(0), WR(1) > > > > + * [in] param[0].u.value.b i2c adapter > > > > + * [in] param[0].u.value.c i2c chip > > > > + * > > > > + * [io] param[1].u.tmem.buf_ptr physical address > > > > + * [io] param[1].u.tmem.size transfer size in bytes > > > > + * [io] param[1].u.tmem.shm_ref shared memory reference > > This should be "[in/out] memref[1]" instead to be able to use > all kinds of memory references. > > > > > + * > > > > + * [out] param[0].u.value.a bytes transferred > > > > + * > > > > + */ > > > > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER 8 > > > > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD 0 > > > > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR 1 > > > > + > > > > #endif /* _OPTEE_MSG_H */ > > > > diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c > > > > index b4ade54d1f28..21d452805c6f 100644 > > > > --- a/drivers/tee/optee/rpc.c > > > > +++ b/drivers/tee/optee/rpc.c > > > > @@ -9,6 +9,7 @@ > > > > #include <linux/device.h> > > > > #include <linux/slab.h> > > > > #include <linux/tee_drv.h> > > > > +#include <linux/i2c.h> > > > > #include "optee_private.h" > > > > #include "optee_smc.h" > > > > > > > > @@ -48,6 +49,59 @@ static void handle_rpc_func_cmd_get_time(struct > > > > optee_msg_arg *arg) > > > > bad: > > > > arg->ret = TEEC_ERROR_BAD_PARAMETERS; > > > > } > > > > +static void handle_rpc_func_cmd_i2c_transfer(struct tee_context *ctx, > > > > + struct optee_msg_arg *arg) > > > > +{ > > > > + struct i2c_client client; > > > > + struct tee_shm *shm; > > > > + int i, ret; > > > > + char *buf; > > > > + uint32_t attr[] = { > > > > + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT, > > > > + OPTEE_MSG_ATTR_TYPE_TMEM_INOUT, > > > > + OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT, > > > > + }; > > > > + > > > > + if (arg->num_params != ARRAY_SIZE(attr)) > > > > + goto bad; > > Use optee_from_msg_param() to translate this into a struct tee_param, > that way you cover all kinds of memory references. Before returning it > nees to be translated back with optee_to_msg_param(). > > Cheers, > Jens > > > > > + > > > > + for (i = 0; i < ARRAY_SIZE(attr); i++) > > > > + if ((arg->params[i].attr & OPTEE_MSG_ATTR_TYPE_MASK) != > > > > attr[i]) > > > > + goto bad; > > > > + > > > > + shm = (struct tee_shm *)(unsigned > > > > long)arg->params[1].u.tmem.shm_ref; > > > > + buf = (char *)shm->kaddr; > > > > + > > > > + client.addr = arg->params[0].u.value.c; > > > > + client.adapter = i2c_get_adapter(arg->params[0].u.value.b); > > > > + if (!client.adapter) > > > > + goto bad; > > > > + > > > > + snprintf(client.name, I2C_NAME_SIZE, "i2c%d", > > > > client.adapter->nr); > > > > + > > > > + switch (arg->params[0].u.value.a) { > > > > + case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD: > > > > + ret = i2c_master_recv(&client, buf, > > > > arg->params[1].u.tmem.size); > > > > + break; > > > > + case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR: > > > > + ret = i2c_master_send(&client, buf, > > > > arg->params[1].u.tmem.size); > > > > + break; > > > > + default: > > > > + i2c_put_adapter(client.adapter); > > > > + goto bad; > > > > + } > > > > + > > > > + if (ret >= 0) { > > > > + arg->params[2].u.value.a = ret; > > > > + arg->ret = TEEC_SUCCESS; > > > > + } else > > > > + arg->ret = TEEC_ERROR_COMMUNICATION; > > > > + > > > > + i2c_put_adapter(client.adapter); > > > > + return; > > > > +bad: > > > > + arg->ret = TEEC_ERROR_BAD_PARAMETERS; > > > > +} > > > > > > > > static struct wq_entry *wq_entry_get(struct optee_wait_queue *wq, u32 > > > > key) > > > > { > > > > @@ -382,6 +436,9 @@ static void handle_rpc_func_cmd(struct tee_context > > > > *ctx, struct optee *optee, > > > > case OPTEE_MSG_RPC_CMD_SHM_FREE: > > > > handle_rpc_func_cmd_shm_free(ctx, arg); > > > > break; > > > > + case OPTEE_MSG_RPC_CMD_I2C_TRANSFER: > > > > + handle_rpc_func_cmd_i2c_transfer(ctx, arg); > > > > + break; > > > > default: > > > > handle_rpc_supp_cmd(ctx, arg); > > > > } > > > > -- > > > > 2.17.1 > > > > > > > > _______________________________________________ > > > > Tee-dev mailing list > > > > tee-...@lists.linaro.org > > > > https://lists.linaro.org/mailman/listinfo/tee-dev
