314 lines
7.5 KiB
C
314 lines
7.5 KiB
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
/*
|
||
|
|
* Copyright (C) 2019-2021 Linaro Ltd.
|
||
|
|
*
|
||
|
|
* Author:
|
||
|
|
* Sumit Garg <sumit.garg@linaro.org>
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/err.h>
|
||
|
|
#include <linux/key-type.h>
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/slab.h>
|
||
|
|
#include <linux/string.h>
|
||
|
|
#include <linux/tee_drv.h>
|
||
|
|
#include <linux/uuid.h>
|
||
|
|
|
||
|
|
#include <keys/trusted_tee.h>
|
||
|
|
|
||
|
|
#define DRIVER_NAME "trusted-key-tee"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Get random data for symmetric key
|
||
|
|
*
|
||
|
|
* [out] memref[0] Random data
|
||
|
|
*/
|
||
|
|
#define TA_CMD_GET_RANDOM 0x0
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Seal trusted key using hardware unique key
|
||
|
|
*
|
||
|
|
* [in] memref[0] Plain key
|
||
|
|
* [out] memref[1] Sealed key datablob
|
||
|
|
*/
|
||
|
|
#define TA_CMD_SEAL 0x1
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Unseal trusted key using hardware unique key
|
||
|
|
*
|
||
|
|
* [in] memref[0] Sealed key datablob
|
||
|
|
* [out] memref[1] Plain key
|
||
|
|
*/
|
||
|
|
#define TA_CMD_UNSEAL 0x2
|
||
|
|
|
||
|
|
/**
|
||
|
|
* struct trusted_key_tee_private - TEE Trusted key private data
|
||
|
|
* @dev: TEE based Trusted key device.
|
||
|
|
* @ctx: TEE context handler.
|
||
|
|
* @session_id: Trusted key TA session identifier.
|
||
|
|
* @shm_pool: Memory pool shared with TEE device.
|
||
|
|
*/
|
||
|
|
struct trusted_key_tee_private {
|
||
|
|
struct device *dev;
|
||
|
|
struct tee_context *ctx;
|
||
|
|
u32 session_id;
|
||
|
|
struct tee_shm *shm_pool;
|
||
|
|
};
|
||
|
|
|
||
|
|
static struct trusted_key_tee_private pvt_data;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Have the TEE seal(encrypt) the symmetric key
|
||
|
|
*/
|
||
|
|
static int trusted_tee_seal(struct trusted_key_payload *p, char *datablob)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
struct tee_ioctl_invoke_arg inv_arg;
|
||
|
|
struct tee_param param[4];
|
||
|
|
struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL;
|
||
|
|
|
||
|
|
memset(&inv_arg, 0, sizeof(inv_arg));
|
||
|
|
memset(¶m, 0, sizeof(param));
|
||
|
|
|
||
|
|
reg_shm_in = tee_shm_register_kernel_buf(pvt_data.ctx, p->key,
|
||
|
|
p->key_len);
|
||
|
|
if (IS_ERR(reg_shm_in)) {
|
||
|
|
dev_err(pvt_data.dev, "key shm register failed\n");
|
||
|
|
return PTR_ERR(reg_shm_in);
|
||
|
|
}
|
||
|
|
|
||
|
|
reg_shm_out = tee_shm_register_kernel_buf(pvt_data.ctx, p->blob,
|
||
|
|
sizeof(p->blob));
|
||
|
|
if (IS_ERR(reg_shm_out)) {
|
||
|
|
dev_err(pvt_data.dev, "blob shm register failed\n");
|
||
|
|
ret = PTR_ERR(reg_shm_out);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
inv_arg.func = TA_CMD_SEAL;
|
||
|
|
inv_arg.session = pvt_data.session_id;
|
||
|
|
inv_arg.num_params = 4;
|
||
|
|
|
||
|
|
param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
|
||
|
|
param[0].u.memref.shm = reg_shm_in;
|
||
|
|
param[0].u.memref.size = p->key_len;
|
||
|
|
param[0].u.memref.shm_offs = 0;
|
||
|
|
param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
|
||
|
|
param[1].u.memref.shm = reg_shm_out;
|
||
|
|
param[1].u.memref.size = sizeof(p->blob);
|
||
|
|
param[1].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_SEAL invoke err: %x\n",
|
||
|
|
inv_arg.ret);
|
||
|
|
ret = -EFAULT;
|
||
|
|
} else {
|
||
|
|
p->blob_len = param[1].u.memref.size;
|
||
|
|
}
|
||
|
|
|
||
|
|
out:
|
||
|
|
if (reg_shm_out)
|
||
|
|
tee_shm_free(reg_shm_out);
|
||
|
|
if (reg_shm_in)
|
||
|
|
tee_shm_free(reg_shm_in);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Have the TEE unseal(decrypt) the symmetric key
|
||
|
|
*/
|
||
|
|
static int trusted_tee_unseal(struct trusted_key_payload *p, char *datablob)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
struct tee_ioctl_invoke_arg inv_arg;
|
||
|
|
struct tee_param param[4];
|
||
|
|
struct tee_shm *reg_shm_in = NULL, *reg_shm_out = NULL;
|
||
|
|
|
||
|
|
memset(&inv_arg, 0, sizeof(inv_arg));
|
||
|
|
memset(¶m, 0, sizeof(param));
|
||
|
|
|
||
|
|
reg_shm_in = tee_shm_register_kernel_buf(pvt_data.ctx, p->blob,
|
||
|
|
p->blob_len);
|
||
|
|
if (IS_ERR(reg_shm_in)) {
|
||
|
|
dev_err(pvt_data.dev, "blob shm register failed\n");
|
||
|
|
return PTR_ERR(reg_shm_in);
|
||
|
|
}
|
||
|
|
|
||
|
|
reg_shm_out = tee_shm_register_kernel_buf(pvt_data.ctx, p->key,
|
||
|
|
sizeof(p->key));
|
||
|
|
if (IS_ERR(reg_shm_out)) {
|
||
|
|
dev_err(pvt_data.dev, "key shm register failed\n");
|
||
|
|
ret = PTR_ERR(reg_shm_out);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
inv_arg.func = TA_CMD_UNSEAL;
|
||
|
|
inv_arg.session = pvt_data.session_id;
|
||
|
|
inv_arg.num_params = 4;
|
||
|
|
|
||
|
|
param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT;
|
||
|
|
param[0].u.memref.shm = reg_shm_in;
|
||
|
|
param[0].u.memref.size = p->blob_len;
|
||
|
|
param[0].u.memref.shm_offs = 0;
|
||
|
|
param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
|
||
|
|
param[1].u.memref.shm = reg_shm_out;
|
||
|
|
param[1].u.memref.size = sizeof(p->key);
|
||
|
|
param[1].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_UNSEAL invoke err: %x\n",
|
||
|
|
inv_arg.ret);
|
||
|
|
ret = -EFAULT;
|
||
|
|
} else {
|
||
|
|
p->key_len = param[1].u.memref.size;
|
||
|
|
}
|
||
|
|
|
||
|
|
out:
|
||
|
|
if (reg_shm_out)
|
||
|
|
tee_shm_free(reg_shm_out);
|
||
|
|
if (reg_shm_in)
|
||
|
|
tee_shm_free(reg_shm_in);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Have the TEE generate random symmetric key
|
||
|
|
*/
|
||
|
|
static int trusted_tee_get_random(unsigned char *key, size_t key_len)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
struct tee_ioctl_invoke_arg inv_arg;
|
||
|
|
struct tee_param param[4];
|
||
|
|
struct tee_shm *reg_shm = NULL;
|
||
|
|
|
||
|
|
memset(&inv_arg, 0, sizeof(inv_arg));
|
||
|
|
memset(¶m, 0, sizeof(param));
|
||
|
|
|
||
|
|
reg_shm = tee_shm_register_kernel_buf(pvt_data.ctx, key, key_len);
|
||
|
|
if (IS_ERR(reg_shm)) {
|
||
|
|
dev_err(pvt_data.dev, "key shm register failed\n");
|
||
|
|
return PTR_ERR(reg_shm);
|
||
|
|
}
|
||
|
|
|
||
|
|
inv_arg.func = TA_CMD_GET_RANDOM;
|
||
|
|
inv_arg.session = pvt_data.session_id;
|
||
|
|
inv_arg.num_params = 4;
|
||
|
|
|
||
|
|
param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
|
||
|
|
param[0].u.memref.shm = reg_shm;
|
||
|
|
param[0].u.memref.size = key_len;
|
||
|
|
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_RANDOM invoke err: %x\n",
|
||
|
|
inv_arg.ret);
|
||
|
|
ret = -EFAULT;
|
||
|
|
} else {
|
||
|
|
ret = param[0].u.memref.size;
|
||
|
|
}
|
||
|
|
|
||
|
|
tee_shm_free(reg_shm);
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
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 trusted_key_probe(struct device *dev)
|
||
|
|
{
|
||
|
|
struct tee_client_device *rng_device = to_tee_client_device(dev);
|
||
|
|
int ret;
|
||
|
|
struct tee_ioctl_open_session_arg sess_arg;
|
||
|
|
|
||
|
|
memset(&sess_arg, 0, sizeof(sess_arg));
|
||
|
|
|
||
|
|
pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL,
|
||
|
|
NULL);
|
||
|
|
if (IS_ERR(pvt_data.ctx))
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN);
|
||
|
|
sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL;
|
||
|
|
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);
|
||
|
|
ret = -EINVAL;
|
||
|
|
goto out_ctx;
|
||
|
|
}
|
||
|
|
pvt_data.session_id = sess_arg.session;
|
||
|
|
|
||
|
|
ret = register_key_type(&key_type_trusted);
|
||
|
|
if (ret < 0)
|
||
|
|
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 ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int trusted_key_remove(struct device *dev)
|
||
|
|
{
|
||
|
|
unregister_key_type(&key_type_trusted);
|
||
|
|
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 trusted_key_id_table[] = {
|
||
|
|
{UUID_INIT(0xf04a0fe7, 0x1f5d, 0x4b9b,
|
||
|
|
0xab, 0xf7, 0x61, 0x9b, 0x85, 0xb4, 0xce, 0x8c)},
|
||
|
|
{}
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(tee, trusted_key_id_table);
|
||
|
|
|
||
|
|
static struct tee_client_driver trusted_key_driver = {
|
||
|
|
.id_table = trusted_key_id_table,
|
||
|
|
.driver = {
|
||
|
|
.name = DRIVER_NAME,
|
||
|
|
.bus = &tee_bus_type,
|
||
|
|
.probe = trusted_key_probe,
|
||
|
|
.remove = trusted_key_remove,
|
||
|
|
},
|
||
|
|
};
|
||
|
|
|
||
|
|
static int trusted_tee_init(void)
|
||
|
|
{
|
||
|
|
return driver_register(&trusted_key_driver.driver);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void trusted_tee_exit(void)
|
||
|
|
{
|
||
|
|
driver_unregister(&trusted_key_driver.driver);
|
||
|
|
}
|
||
|
|
|
||
|
|
struct trusted_key_ops trusted_key_tee_ops = {
|
||
|
|
.migratable = 0, /* non-migratable */
|
||
|
|
.init = trusted_tee_init,
|
||
|
|
.seal = trusted_tee_seal,
|
||
|
|
.unseal = trusted_tee_unseal,
|
||
|
|
.get_random = trusted_tee_get_random,
|
||
|
|
.exit = trusted_tee_exit,
|
||
|
|
};
|