mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 18:09:57 +00:00
![Andy Shevchenko](/assets/img/avatar_default.png)
There is export_uuid() function which exports uuid_t to the u8 array. Use it instead of open coding variant. This allows to hide the uuid_t internals. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Sumit Garg <sumit.garg@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
306 lines
7.3 KiB
C
306 lines
7.3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) 2018-2019 Linaro Ltd.
|
|
*/
|
|
|
|
#include <linux/delay.h>
|
|
#include <linux/of.h>
|
|
#include <linux/hw_random.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/tee_drv.h>
|
|
#include <linux/uuid.h>
|
|
|
|
#define DRIVER_NAME "optee-rng"
|
|
|
|
#define TEE_ERROR_HEALTH_TEST_FAIL 0x00000001
|
|
|
|
/*
|
|
* TA_CMD_GET_ENTROPY - Get Entropy from RNG
|
|
*
|
|
* param[0] (inout memref) - Entropy buffer memory reference
|
|
* param[1] unused
|
|
* param[2] unused
|
|
* param[3] unused
|
|
*
|
|
* Result:
|
|
* TEE_SUCCESS - Invoke command success
|
|
* TEE_ERROR_BAD_PARAMETERS - Incorrect input param
|
|
* TEE_ERROR_NOT_SUPPORTED - Requested entropy size greater than size of pool
|
|
* TEE_ERROR_HEALTH_TEST_FAIL - Continuous health testing failed
|
|
*/
|
|
#define TA_CMD_GET_ENTROPY 0x0
|
|
|
|
/*
|
|
* TA_CMD_GET_RNG_INFO - Get RNG information
|
|
*
|
|
* param[0] (out value) - value.a: RNG data-rate in bytes per second
|
|
* value.b: Quality/Entropy per 1024 bit of data
|
|
* param[1] unused
|
|
* param[2] unused
|
|
* param[3] unused
|
|
*
|
|
* Result:
|
|
* TEE_SUCCESS - Invoke command success
|
|
* TEE_ERROR_BAD_PARAMETERS - Incorrect input param
|
|
*/
|
|
#define TA_CMD_GET_RNG_INFO 0x1
|
|
|
|
#define MAX_ENTROPY_REQ_SZ (4 * 1024)
|
|
|
|
/**
|
|
* struct optee_rng_private - OP-TEE Random Number Generator private data
|
|
* @dev: OP-TEE based RNG device.
|
|
* @ctx: OP-TEE context handler.
|
|
* @session_id: RNG TA session identifier.
|
|
* @data_rate: RNG data rate.
|
|
* @entropy_shm_pool: Memory pool shared with RNG device.
|
|
* @optee_rng: OP-TEE RNG driver structure.
|
|
*/
|
|
struct optee_rng_private {
|
|
struct device *dev;
|
|
struct tee_context *ctx;
|
|
u32 session_id;
|
|
u32 data_rate;
|
|
struct tee_shm *entropy_shm_pool;
|
|
struct hwrng optee_rng;
|
|
};
|
|
|
|
#define to_optee_rng_private(r) \
|
|
container_of(r, struct optee_rng_private, optee_rng)
|
|
|
|
static size_t get_optee_rng_data(struct optee_rng_private *pvt_data,
|
|
void *buf, size_t req_size)
|
|
{
|
|
int ret = 0;
|
|
u8 *rng_data = NULL;
|
|
size_t rng_size = 0;
|
|
struct tee_ioctl_invoke_arg inv_arg;
|
|
struct tee_param param[4];
|
|
|
|
memset(&inv_arg, 0, sizeof(inv_arg));
|
|
memset(¶m, 0, sizeof(param));
|
|
|
|
/* Invoke TA_CMD_GET_ENTROPY function of Trusted App */
|
|
inv_arg.func = TA_CMD_GET_ENTROPY;
|
|
inv_arg.session = pvt_data->session_id;
|
|
inv_arg.num_params = 4;
|
|
|
|
/* Fill invoke cmd params */
|
|
param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT;
|
|
param[0].u.memref.shm = pvt_data->entropy_shm_pool;
|
|
param[0].u.memref.size = req_size;
|
|
param[0].u.memref.shm_offs = 0;
|
|
|
|
ret = tee_client_invoke_func(pvt_data->ctx, &inv_arg, param);
|
|
if ((ret < 0) || (inv_arg.ret != 0)) {
|
|
dev_err(pvt_data->dev, "TA_CMD_GET_ENTROPY invoke err: %x\n",
|
|
inv_arg.ret);
|
|
return 0;
|
|
}
|
|
|
|
rng_data = tee_shm_get_va(pvt_data->entropy_shm_pool, 0);
|
|
if (IS_ERR(rng_data)) {
|
|
dev_err(pvt_data->dev, "tee_shm_get_va failed\n");
|
|
return 0;
|
|
}
|
|
|
|
rng_size = param[0].u.memref.size;
|
|
memcpy(buf, rng_data, rng_size);
|
|
|
|
return rng_size;
|
|
}
|
|
|
|
static int optee_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
|
|
{
|
|
struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
|
|
size_t read = 0, rng_size = 0;
|
|
int timeout = 1;
|
|
u8 *data = buf;
|
|
|
|
if (max > MAX_ENTROPY_REQ_SZ)
|
|
max = MAX_ENTROPY_REQ_SZ;
|
|
|
|
while (read == 0) {
|
|
rng_size = get_optee_rng_data(pvt_data, data, (max - read));
|
|
|
|
data += rng_size;
|
|
read += rng_size;
|
|
|
|
if (wait) {
|
|
if (timeout-- == 0)
|
|
return read;
|
|
msleep((1000 * (max - read)) / pvt_data->data_rate);
|
|
} else {
|
|
return read;
|
|
}
|
|
}
|
|
|
|
return read;
|
|
}
|
|
|
|
static int optee_rng_init(struct hwrng *rng)
|
|
{
|
|
struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
|
|
struct tee_shm *entropy_shm_pool = NULL;
|
|
|
|
entropy_shm_pool = tee_shm_alloc(pvt_data->ctx, MAX_ENTROPY_REQ_SZ,
|
|
TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
|
|
if (IS_ERR(entropy_shm_pool)) {
|
|
dev_err(pvt_data->dev, "tee_shm_alloc failed\n");
|
|
return PTR_ERR(entropy_shm_pool);
|
|
}
|
|
|
|
pvt_data->entropy_shm_pool = entropy_shm_pool;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void optee_rng_cleanup(struct hwrng *rng)
|
|
{
|
|
struct optee_rng_private *pvt_data = to_optee_rng_private(rng);
|
|
|
|
tee_shm_free(pvt_data->entropy_shm_pool);
|
|
}
|
|
|
|
static struct optee_rng_private pvt_data = {
|
|
.optee_rng = {
|
|
.name = DRIVER_NAME,
|
|
.init = optee_rng_init,
|
|
.cleanup = optee_rng_cleanup,
|
|
.read = optee_rng_read,
|
|
}
|
|
};
|
|
|
|
static int get_optee_rng_info(struct device *dev)
|
|
{
|
|
int ret = 0;
|
|
struct tee_ioctl_invoke_arg inv_arg;
|
|
struct tee_param param[4];
|
|
|
|
memset(&inv_arg, 0, sizeof(inv_arg));
|
|
memset(¶m, 0, sizeof(param));
|
|
|
|
/* Invoke TA_CMD_GET_RNG_INFO function of Trusted App */
|
|
inv_arg.func = TA_CMD_GET_RNG_INFO;
|
|
inv_arg.session = pvt_data.session_id;
|
|
inv_arg.num_params = 4;
|
|
|
|
/* Fill invoke cmd params */
|
|
param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT;
|
|
|
|
ret = tee_client_invoke_func(pvt_data.ctx, &inv_arg, param);
|
|
if ((ret < 0) || (inv_arg.ret != 0)) {
|
|
dev_err(dev, "TA_CMD_GET_RNG_INFO invoke err: %x\n",
|
|
inv_arg.ret);
|
|
return -EINVAL;
|
|
}
|
|
|
|
pvt_data.data_rate = param[0].u.value.a;
|
|
pvt_data.optee_rng.quality = param[0].u.value.b;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
|
|
{
|
|
if (ver->impl_id == TEE_IMPL_ID_OPTEE)
|
|
return 1;
|
|
else
|
|
return 0;
|
|
}
|
|
|
|
static int optee_rng_probe(struct device *dev)
|
|
{
|
|
struct tee_client_device *rng_device = to_tee_client_device(dev);
|
|
int ret = 0, err = -ENODEV;
|
|
struct tee_ioctl_open_session_arg sess_arg;
|
|
|
|
memset(&sess_arg, 0, sizeof(sess_arg));
|
|
|
|
/* Open context with TEE driver */
|
|
pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,
|
|
NULL);
|
|
if (IS_ERR(pvt_data.ctx))
|
|
return -ENODEV;
|
|
|
|
/* Open session with hwrng Trusted App */
|
|
export_uuid(sess_arg.uuid, &rng_device->id.uuid);
|
|
sess_arg.clnt_login = TEE_IOCTL_LOGIN_PUBLIC;
|
|
sess_arg.num_params = 0;
|
|
|
|
ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL);
|
|
if ((ret < 0) || (sess_arg.ret != 0)) {
|
|
dev_err(dev, "tee_client_open_session failed, err: %x\n",
|
|
sess_arg.ret);
|
|
err = -EINVAL;
|
|
goto out_ctx;
|
|
}
|
|
pvt_data.session_id = sess_arg.session;
|
|
|
|
err = get_optee_rng_info(dev);
|
|
if (err)
|
|
goto out_sess;
|
|
|
|
err = hwrng_register(&pvt_data.optee_rng);
|
|
if (err) {
|
|
dev_err(dev, "hwrng registration failed (%d)\n", err);
|
|
goto out_sess;
|
|
}
|
|
|
|
pvt_data.dev = dev;
|
|
|
|
return 0;
|
|
|
|
out_sess:
|
|
tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
|
|
out_ctx:
|
|
tee_client_close_context(pvt_data.ctx);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int optee_rng_remove(struct device *dev)
|
|
{
|
|
hwrng_unregister(&pvt_data.optee_rng);
|
|
tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
|
|
tee_client_close_context(pvt_data.ctx);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct tee_client_device_id optee_rng_id_table[] = {
|
|
{UUID_INIT(0xab7a617c, 0xb8e7, 0x4d8f,
|
|
0x83, 0x01, 0xd0, 0x9b, 0x61, 0x03, 0x6b, 0x64)},
|
|
{}
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(tee, optee_rng_id_table);
|
|
|
|
static struct tee_client_driver optee_rng_driver = {
|
|
.id_table = optee_rng_id_table,
|
|
.driver = {
|
|
.name = DRIVER_NAME,
|
|
.bus = &tee_bus_type,
|
|
.probe = optee_rng_probe,
|
|
.remove = optee_rng_remove,
|
|
},
|
|
};
|
|
|
|
static int __init optee_rng_mod_init(void)
|
|
{
|
|
return driver_register(&optee_rng_driver.driver);
|
|
}
|
|
|
|
static void __exit optee_rng_mod_exit(void)
|
|
{
|
|
driver_unregister(&optee_rng_driver.driver);
|
|
}
|
|
|
|
module_init(optee_rng_mod_init);
|
|
module_exit(optee_rng_mod_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_AUTHOR("Sumit Garg <sumit.garg@linaro.org>");
|
|
MODULE_DESCRIPTION("OP-TEE based random number generator driver");
|