Add UCLASS_TEE for Trusted Execution Environment
authorJens Wiklander <jens.wiklander@linaro.org>
Tue, 25 Sep 2018 14:40:09 +0000 (16:40 +0200)
committerTom Rini <trini@konsulko.com>
Sun, 7 Oct 2018 14:47:38 +0000 (10:47 -0400)
Adds a uclass to interface with a TEE (Trusted Execution Environment).

A TEE driver is a driver that interfaces with a trusted OS running in
some secure environment, for example, TrustZone on ARM cpus, or a
separate secure co-processor etc.

The TEE subsystem can serve a TEE driver for a Global Platform compliant
TEE, but it's not limited to only Global Platform TEEs.

The over all design is based on the TEE subsystem in the Linux kernel,
tailored for U-Boot.

Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Igor Opaniuk <igor.opaniuk@linaro.org>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
MAINTAINERS
drivers/Kconfig
drivers/Makefile
drivers/tee/Kconfig [new file with mode: 0644]
drivers/tee/Makefile [new file with mode: 0644]
drivers/tee/tee-uclass.c [new file with mode: 0644]
include/dm/uclass-id.h
include/tee.h [new file with mode: 0644]

index 6b4d00a476882a884b1b12ca8878a8b7249ee608..dac76e0ee27b8f057249d01d56a1245445c0ad33 100644 (file)
@@ -629,6 +629,12 @@ TQ GROUP
 S:     Orphaned (Since 2016-02)
 T:     git git://git.denx.de/u-boot-tq-group.git
 
+TEE
+M:     Jens Wiklander <jens.wiklander@linaro.org>
+S:     Maintained
+F:     drivers/tee/
+F:     include/tee.h
+
 UBI
 M:     Kyungmin Park <kmpark@infradead.org>
 M:     Heiko Schocher <hs@denx.de>
index 11b88a1e1a85b0c1bc777946773ba84ecc13a690..927a2b87f6a7dda6b8e55388e3ee4e22c3fa9c14 100644 (file)
@@ -100,6 +100,8 @@ source "drivers/spmi/Kconfig"
 
 source "drivers/sysreset/Kconfig"
 
+source "drivers/tee/Kconfig"
+
 source "drivers/thermal/Kconfig"
 
 source "drivers/timer/Kconfig"
index e3b9e8c635ebb31d852151340b0a50c5cdd9b5f1..fb38b67541340d0897518915ba0b416adf82e9f8 100644 (file)
@@ -105,6 +105,7 @@ obj-y += input/
 obj-y += smem/
 obj-y += soc/
 obj-y += thermal/
+obj-$(CONFIG_TEE) += tee/
 obj-y += axi/
 obj-$(CONFIG_W1) += w1/
 obj-$(CONFIG_W1_EEPROM) += w1-eeprom/
diff --git a/drivers/tee/Kconfig b/drivers/tee/Kconfig
new file mode 100644 (file)
index 0000000..f3fc3c2
--- /dev/null
@@ -0,0 +1,11 @@
+# Generic Trusted Execution Environment Configuration
+config TEE
+       bool "Trusted Execution Environment support"
+       depends on ARM && (ARM64 || CPU_V7A)
+       select ARM_SMCCC
+       help
+         This implements a generic interface towards a Trusted Execution
+         Environment (TEE). A TEE is a trusted OS running in some secure
+         environment, for example, TrustZone on ARM cpus, or a separate
+         secure co-processor etc. See also:
+         https://en.wikipedia.org/wiki/Trusted_execution_environment
diff --git a/drivers/tee/Makefile b/drivers/tee/Makefile
new file mode 100644 (file)
index 0000000..b6d8e16
--- /dev/null
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0+
+
+obj-y += tee-uclass.o
diff --git a/drivers/tee/tee-uclass.c b/drivers/tee/tee-uclass.c
new file mode 100644 (file)
index 0000000..1bee54e
--- /dev/null
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2018 Linaro Limited
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/device-internal.h>
+#include <dm/uclass-internal.h>
+#include <tee.h>
+
+/**
+ * struct tee_uclass_priv - information of a TEE, stored by the uclass
+ *
+ * @list_shm:  list of structe tee_shm representing memory blocks shared
+ *             with the TEE.
+ */
+struct tee_uclass_priv {
+       struct list_head list_shm;
+};
+
+static const struct tee_driver_ops *tee_get_ops(struct udevice *dev)
+{
+       return device_get_ops(dev);
+}
+
+void tee_get_version(struct udevice *dev, struct tee_version_data *vers)
+{
+       tee_get_ops(dev)->get_version(dev, vers);
+}
+
+int tee_open_session(struct udevice *dev, struct tee_open_session_arg *arg,
+                    uint num_param, struct tee_param *param)
+{
+       return tee_get_ops(dev)->open_session(dev, arg, num_param, param);
+}
+
+int tee_close_session(struct udevice *dev, u32 session)
+{
+       return tee_get_ops(dev)->close_session(dev, session);
+}
+
+int tee_invoke_func(struct udevice *dev, struct tee_invoke_arg *arg,
+                   uint num_param, struct tee_param *param)
+{
+       return tee_get_ops(dev)->invoke_func(dev, arg, num_param, param);
+}
+
+int __tee_shm_add(struct udevice *dev, ulong align, void *addr, ulong size,
+                 u32 flags, struct tee_shm **shmp)
+{
+       struct tee_shm *shm;
+       void *p = addr;
+       int rc;
+
+       if (flags & TEE_SHM_ALLOC) {
+               if (align)
+                       p = memalign(align, size);
+               else
+                       p = malloc(size);
+       }
+       if (!p)
+               return -ENOMEM;
+
+       shm = calloc(1, sizeof(*shm));
+       if (!shm) {
+               rc = -ENOMEM;
+               goto err;
+       }
+
+       shm->dev = dev;
+       shm->addr = p;
+       shm->size = size;
+       shm->flags = flags;
+
+       if (flags & TEE_SHM_SEC_REGISTER) {
+               rc = tee_get_ops(dev)->shm_register(dev, shm);
+               if (rc)
+                       goto err;
+       }
+
+       if (flags & TEE_SHM_REGISTER) {
+               struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+
+               list_add(&shm->link, &priv->list_shm);
+       }
+
+       *shmp = shm;
+
+       return 0;
+err:
+       free(shm);
+       if (flags & TEE_SHM_ALLOC)
+               free(p);
+
+       return rc;
+}
+
+int tee_shm_alloc(struct udevice *dev, ulong size, u32 flags,
+                 struct tee_shm **shmp)
+{
+       u32 f = flags;
+
+       f |= TEE_SHM_SEC_REGISTER | TEE_SHM_REGISTER | TEE_SHM_ALLOC;
+
+       return __tee_shm_add(dev, 0, NULL, size, f, shmp);
+}
+
+int tee_shm_register(struct udevice *dev, void *addr, ulong size, u32 flags,
+                    struct tee_shm **shmp)
+{
+       u32 f = flags & ~TEE_SHM_ALLOC;
+
+       f |= TEE_SHM_SEC_REGISTER | TEE_SHM_REGISTER;
+
+       return __tee_shm_add(dev, 0, addr, size, f, shmp);
+}
+
+void tee_shm_free(struct tee_shm *shm)
+{
+       if (!shm)
+               return;
+
+       if (shm->flags & TEE_SHM_SEC_REGISTER)
+               tee_get_ops(shm->dev)->shm_unregister(shm->dev, shm);
+
+       if (shm->flags & TEE_SHM_REGISTER)
+               list_del(&shm->link);
+
+       if (shm->flags & TEE_SHM_ALLOC)
+               free(shm->addr);
+
+       free(shm);
+}
+
+bool tee_shm_is_registered(struct tee_shm *shm, struct udevice *dev)
+{
+       struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+       struct tee_shm *s;
+
+       list_for_each_entry(s, &priv->list_shm, link)
+               if (s == shm)
+                       return true;
+
+       return false;
+}
+
+struct udevice *tee_find_device(struct udevice *start,
+                               int (*match)(struct tee_version_data *vers,
+                                            const void *data),
+                               const void *data,
+                               struct tee_version_data *vers)
+{
+       struct udevice *dev = start;
+       struct tee_version_data lv;
+       struct tee_version_data *v = vers ? vers : &lv;
+
+       if (!dev)
+               uclass_find_first_device(UCLASS_TEE, &dev);
+       else
+               uclass_find_next_device(&dev);
+
+       for (; dev; uclass_find_next_device(&dev)) {
+               if (device_probe(dev))
+                       continue;
+               tee_get_ops(dev)->get_version(dev, v);
+               if (!match || match(v, data))
+                       return dev;
+       }
+
+       return NULL;
+}
+
+static int tee_pre_probe(struct udevice *dev)
+{
+       struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+
+       INIT_LIST_HEAD(&priv->list_shm);
+
+       return 0;
+}
+
+static int tee_pre_remove(struct udevice *dev)
+{
+       struct tee_uclass_priv *priv = dev_get_uclass_priv(dev);
+       struct tee_shm *shm;
+
+       /*
+        * Any remaining shared memory must be unregistered now as U-Boot
+        * is about to hand over to the next stage and that memory will be
+        * reused.
+        */
+       while (!list_empty(&priv->list_shm)) {
+               shm = list_first_entry(&priv->list_shm, struct tee_shm, link);
+               debug("%s: freeing leftover shm %p (size %lu, flags %#x)\n",
+                     __func__, (void *)shm, shm->size, shm->flags);
+               tee_shm_free(shm);
+       }
+
+       return 0;
+}
+
+UCLASS_DRIVER(tee) = {
+       .id = UCLASS_TEE,
+       .name = "tee",
+       .per_device_auto_alloc_size = sizeof(struct tee_uclass_priv),
+       .pre_probe = tee_pre_probe,
+       .pre_remove = tee_pre_remove,
+};
index 79fd3008d59bb08d57df8391378527ea9d0227d4..269a2c6e722831d704ed2bc8de9d728a957b342f 100644 (file)
@@ -85,6 +85,7 @@ enum uclass_id {
        UCLASS_SPI_GENERIC,     /* Generic SPI flash target */
        UCLASS_SYSCON,          /* System configuration device */
        UCLASS_SYSRESET,        /* System reset device */
+       UCLASS_TEE,             /* Trusted Execution Environment device */
        UCLASS_THERMAL,         /* Thermal sensor */
        UCLASS_TIMER,           /* Timer device */
        UCLASS_TPM,             /* Trusted Platform Module TIS interface */
diff --git a/include/tee.h b/include/tee.h
new file mode 100644 (file)
index 0000000..b86dbec
--- /dev/null
@@ -0,0 +1,336 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2018 Linaro Limited
+ */
+
+#ifndef __TEE_H
+#define __TEE_H
+
+#define TEE_UUID_LEN           16
+
+#define TEE_GEN_CAP_GP          BIT(0) /* GlobalPlatform compliant TEE */
+#define TEE_GEN_CAP_REG_MEM     BIT(1) /* Supports registering shared memory */
+
+#define TEE_SHM_REGISTER       BIT(0)  /* In list of shared memory */
+#define TEE_SHM_SEC_REGISTER   BIT(1)  /* TEE notified of this memory */
+#define TEE_SHM_ALLOC          BIT(2)  /* The memory is malloced() and must */
+                                       /* be freed() */
+
+#define TEE_PARAM_ATTR_TYPE_NONE               0       /* parameter not used */
+#define TEE_PARAM_ATTR_TYPE_VALUE_INPUT                1
+#define TEE_PARAM_ATTR_TYPE_VALUE_OUTPUT       2
+#define TEE_PARAM_ATTR_TYPE_VALUE_INOUT                3       /* input and output */
+#define TEE_PARAM_ATTR_TYPE_MEMREF_INPUT       5
+#define TEE_PARAM_ATTR_TYPE_MEMREF_OUTPUT      6
+#define TEE_PARAM_ATTR_TYPE_MEMREF_INOUT       7       /* input and output */
+#define TEE_PARAM_ATTR_TYPE_MASK               0xff
+#define TEE_PARAM_ATTR_META                    0x100
+#define TEE_PARAM_ATTR_MASK                    (TEE_PARAM_ATTR_TYPE_MASK | \
+                                                TEE_PARAM_ATTR_META)
+
+/*
+ * Some Global Platform error codes which has a meaning if the
+ * TEE_GEN_CAP_GP bit is returned by the driver in
+ * struct tee_version_data::gen_caps
+ */
+#define TEE_SUCCESS                    0x00000000
+#define TEE_ERROR_GENERIC              0xffff0000
+#define TEE_ERROR_BAD_PARAMETERS       0xffff0006
+#define TEE_ERROR_ITEM_NOT_FOUND       0xffff0008
+#define TEE_ERROR_NOT_IMPLEMENTED      0xffff0009
+#define TEE_ERROR_NOT_SUPPORTED                0xffff000a
+#define TEE_ERROR_COMMUNICATION                0xffff000e
+#define TEE_ERROR_SECURITY             0xffff000f
+#define TEE_ERROR_OUT_OF_MEMORY                0xffff000c
+#define TEE_ERROR_TARGET_DEAD          0xffff3024
+
+#define TEE_ORIGIN_COMMS               0x00000002
+#define TEE_ORIGIN_TEE                 0x00000003
+#define TEE_ORIGIN_TRUSTED_APP         0x00000004
+
+struct udevice;
+/**
+ * struct tee_shm - memory shared with the TEE
+ * @dev:       The TEE device
+ * @link:      List node in the list in struct struct tee_uclass_priv
+ * @addr:      Pointer to the shared memory
+ * @size:      Size of the the shared memory
+ * @flags:     TEE_SHM_* above
+ */
+struct tee_shm {
+       struct udevice *dev;
+       struct list_head link;
+       void *addr;
+       ulong size;
+       u32 flags;
+};
+
+/**
+ * struct tee_param_memref - memory reference for a Trusted Application
+ * @shm_offs:  Offset in bytes into the shared memory object @shm
+ * @size:      Size in bytes of the memory reference
+ * @shm:       Pointer to a shared memory object for the buffer
+ *
+ * Used as a part of struct tee_param, see that for more information.
+ */
+struct tee_param_memref {
+       ulong shm_offs;
+       ulong size;
+       struct tee_shm *shm;
+};
+
+/**
+ * struct tee_param_value - value parameter for a Trusted Application
+ * @a, @b, @c: Parameters passed by value
+ *
+ * Used as a part of struct tee_param, see that for more information.
+ */
+struct tee_param_value {
+       u64 a;
+       u64 b;
+       u64 c;
+};
+
+/**
+ * struct tee_param - invoke parameter for a Trusted Application
+ * @attr:      Attributes
+ * @u.memref:  Memref parameter if (@attr & TEE_PARAM_ATTR_MASK) is one of
+ *             TEE_PARAM_ATTR_TYPE_MEMREF_* above
+ * @u.value:   Value parameter if (@attr & TEE_PARAM_ATTR_MASK) is one of
+ *             TEE_PARAM_ATTR_TYPE_VALUE_* above
+ *
+ * Parameters to TA are passed using an array of this struct, for
+ * flexibility both value parameters and memory refereces can be used.
+ */
+struct tee_param {
+       u64 attr;
+       union {
+               struct tee_param_memref memref;
+               struct tee_param_value value;
+       } u;
+};
+
+/**
+ * struct tee_open_session_arg - extra arguments for tee_open_session()
+ * @uuid:      [in] UUID of the Trusted Application
+ * @clnt_uuid: [in] Normally zeroes
+ * @clnt_login:        [in] Normally 0
+ * @session:   [out] Session id
+ * @ret:       [out] return value
+ * @ret_origin:        [out] origin of the return value
+ */
+struct tee_open_session_arg {
+       u8 uuid[TEE_UUID_LEN];
+       u8 clnt_uuid[TEE_UUID_LEN];
+       u32 clnt_login;
+       u32 session;
+       u32 ret;
+       u32 ret_origin;
+};
+
+/**
+ * struct tee_invoke_arg - extra arguments for tee_invoke_func()
+ * @func:      [in] Trusted Application function, specific to the TA
+ * @session:   [in] Session id, from open session
+ * @ret:       [out] return value
+ * @ret_origin:        [out] origin of the return value
+ */
+struct tee_invoke_arg {
+       u32 func;
+       u32 session;
+       u32 ret;
+       u32 ret_origin;
+};
+
+/**
+ * struct tee_version_data - description of TEE
+ * @gen_caps:  Generic capabilities, TEE_GEN_CAP_* above
+ */
+struct tee_version_data {
+       u32 gen_caps;
+};
+
+/**
+ * struct tee_driver_ops - TEE driver operations
+ * @get_version:       Query capabilities of TEE device,
+ * @open_session:      Opens a session to a Trusted Application in the TEE,
+ * @close_session:     Closes a session to Trusted Application,
+ * @invoke_func:       Invokes a function in a Trusted Application,
+ * @shm_register:      Registers memory shared with the TEE
+ * @shm_unregister:    Unregisters memory shared with the TEE
+ */
+struct tee_driver_ops {
+       /**
+        * get_version() - Query capabilities of TEE device
+        * @dev:        The TEE device
+        * @vers:       Pointer to version data
+        */
+       void (*get_version)(struct udevice *dev, struct tee_version_data *vers);
+       /**
+        * open_session() - Open a session to a Trusted Application
+        * @dev:        The TEE device
+        * @arg:        Open session arguments
+        * @num_param:  Number of elements in @param
+        * @param:      Parameters for Trusted Application
+        *
+        * Returns < 0 on error else see @arg->ret for result. If @arg->ret is
+        * TEE_SUCCESS the session identifier is available in @arg->session.
+        */
+       int (*open_session)(struct udevice *dev,
+                           struct tee_open_session_arg *arg, uint num_param,
+                           struct tee_param *param);
+       /**
+        * close_session() - Close a session to a Trusted Application
+        * @dev:        The TEE device
+        * @session:    Session id
+        *
+        * Return < 0 on error else 0, regardless the session will not be valid
+        * after this function has returned.
+        */
+       int (*close_session)(struct udevice *dev, u32 session);
+       /**
+        * tee_invoke_func() - Invoke a function in a Trusted Application
+        * @dev:        The TEE device
+        * @arg:        Invoke arguments
+        * @num_param:  Number of elements in @param
+        * @param:      Parameters for Trusted Application
+        *
+        * Returns < 0 on error else see @arg->ret for result.
+        */
+       int (*invoke_func)(struct udevice *dev, struct tee_invoke_arg *arg,
+                          uint num_param, struct tee_param *param);
+       /**
+        * shm_register() - Registers memory shared with the TEE
+        * @dev:        The TEE device
+        * @shm:        Pointer to a shared memory object
+        * Returns 0 on success or < 0 on failure.
+        */
+       int (*shm_register)(struct udevice *dev, struct tee_shm *shm);
+       /**
+        * shm_unregister() - Unregisters memory shared with the TEE
+        * @dev:        The TEE device
+        * @shm:        Pointer to a shared memory object
+        * Returns 0 on success or < 0 on failure.
+        */
+       int (*shm_unregister)(struct udevice *dev, struct tee_shm *shm);
+};
+
+/**
+ * __tee_shm_add() - Internal helper function to register shared memory
+ * @dev:       The TEE device
+ * @align:     Required alignment of allocated memory block if
+ *             (@flags & TEE_SHM_ALLOC)
+ * @addr:      Address of memory block, ignored if (@flags & TEE_SHM_ALLOC)
+ * @size:      Size of memory block
+ * @flags:     TEE_SHM_* above
+ * @shmp:      If the function return 0, this holds the allocated
+ *             struct tee_shm
+ *
+ * returns 0 on success or < 0 on failure.
+ */
+int __tee_shm_add(struct udevice *dev, ulong align, void *addr, ulong size,
+                 u32 flags, struct tee_shm **shmp);
+
+/**
+ * tee_shm_alloc() - Allocate shared memory
+ * @dev:       The TEE device
+ * @size:      Size of memory block
+ * @flags:     TEE_SHM_* above
+ * @shmp:      If the function return 0, this holds the allocated
+ *             struct tee_shm
+ *
+ * returns 0 on success or < 0 on failure.
+ */
+int tee_shm_alloc(struct udevice *dev, ulong size, u32 flags,
+                 struct tee_shm **shmp);
+
+/**
+ * tee_shm_register() - Registers shared memory
+ * @dev:       The TEE device
+ * @addr:      Address of memory block
+ * @size:      Size of memory block
+ * @flags:     TEE_SHM_* above
+ * @shmp:      If the function return 0, this holds the allocated
+ *             struct tee_shm
+ *
+ * returns 0 on success or < 0 on failure.
+ */
+int tee_shm_register(struct udevice *dev, void *addr, ulong size, u32 flags,
+                    struct tee_shm **shmp);
+
+/**
+ * tee_shm_free() - Frees shared memory
+ * @shm:       Shared memory object
+ */
+void tee_shm_free(struct tee_shm *shm);
+
+/**
+ * tee_shm_is_registered() - Check register status of shared memory object
+ * @shm:       Pointer to shared memory object
+ * @dev:       The TEE device
+ *
+ * Returns true if the shared memory object is registered for the supplied
+ * TEE device
+ */
+bool tee_shm_is_registered(struct tee_shm *shm, struct udevice *dev);
+
+/**
+ * tee_find_device() - Look up a TEE device
+ * @start:     if not NULL, continue search after this device
+ * @match:     function to check TEE device, returns != 0 if the device
+ *             matches
+ * @data:      data for match function
+ * @vers:      if not NULL, version data of TEE device of the device returned
+ *
+ * Returns a probed TEE device of the first TEE device matched by the
+ * match() callback or NULL.
+ */
+struct udevice *tee_find_device(struct udevice *start,
+                               int (*match)(struct tee_version_data *vers,
+                                            const void *data),
+                               const void *data,
+                               struct tee_version_data *vers);
+
+/**
+ * tee_get_version() - Query capabilities of TEE device
+ * @dev:       The TEE device
+ * @vers:      Pointer to version data
+ */
+void tee_get_version(struct udevice *dev, struct tee_version_data *vers);
+
+/**
+ * tee_open_session() - Open a session to a Trusted Application
+ * @dev:       The TEE device
+ * @arg:       Open session arguments
+ * @num_param: Number of elements in @param
+ * @param:     Parameters for Trusted Application
+ *
+ * Returns < 0 on error else see @arg->ret for result. If @arg->ret is
+ * TEE_SUCCESS the session identifier is available in @arg->session.
+ */
+int tee_open_session(struct udevice *dev, struct tee_open_session_arg *arg,
+                    uint num_param, struct tee_param *param);
+
+/**
+ * tee_close_session() - Close a session to a Trusted Application
+ * @dev:       The TEE device
+ * @session:   Session id
+ *
+ * Return < 0 on error else 0, regardless the session will not be valid
+ * after this function has returned.
+ */
+int tee_close_session(struct udevice *dev, u32 session);
+
+/**
+ * tee_invoke_func() - Invoke a function in a Trusted Application
+ * @dev:       The TEE device
+ * @arg:       Invoke arguments
+ * @num_param: Number of elements in @param
+ * @param:     Parameters for Trusted Application
+ *
+ * Returns < 0 on error else see @arg->ret for result.
+ */
+int tee_invoke_func(struct udevice *dev, struct tee_invoke_arg *arg,
+                   uint num_param, struct tee_param *param);
+
+#endif /* __TEE_H */