diff options
Diffstat (limited to 'drivers/tee/optee/core.c')
| -rw-r--r-- | drivers/tee/optee/core.c | 622 |
1 files changed, 622 insertions, 0 deletions
diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c new file mode 100644 index 000000000000..58169e519422 --- /dev/null +++ b/drivers/tee/optee/core.c @@ -0,0 +1,622 @@ +/* + * Copyright (c) 2015, Linaro Limited + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/arm-smccc.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/tee_drv.h> +#include <linux/types.h> +#include <linux/uaccess.h> +#include "optee_private.h" +#include "optee_smc.h" + +#define DRIVER_NAME "optee" + +#define OPTEE_SHM_NUM_PRIV_PAGES 1 + +/** + * optee_from_msg_param() - convert from OPTEE_MSG parameters to + * struct tee_param + * @params: subsystem internal parameter representation + * @num_params: number of elements in the parameter arrays + * @msg_params: OPTEE_MSG parameters + * Returns 0 on success or <0 on failure + */ +int optee_from_msg_param(struct tee_param *params, size_t num_params, + const struct optee_msg_param *msg_params) +{ + int rc; + size_t n; + struct tee_shm *shm; + phys_addr_t pa; + + for (n = 0; n < num_params; n++) { + struct tee_param *p = params + n; + const struct optee_msg_param *mp = msg_params + n; + u32 attr = mp->attr & OPTEE_MSG_ATTR_TYPE_MASK; + + switch (attr) { + case OPTEE_MSG_ATTR_TYPE_NONE: + p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE; + memset(&p->u, 0, sizeof(p->u)); + break; + case OPTEE_MSG_ATTR_TYPE_VALUE_INPUT: + case OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT: + case OPTEE_MSG_ATTR_TYPE_VALUE_INOUT: + p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT + + attr - OPTEE_MSG_ATTR_TYPE_VALUE_INPUT; + p->u.value.a = mp->u.value.a; + p->u.value.b = mp->u.value.b; + p->u.value.c = mp->u.value.c; + break; + case OPTEE_MSG_ATTR_TYPE_TMEM_INPUT: + case OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT: + case OPTEE_MSG_ATTR_TYPE_TMEM_INOUT: + p->attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT + + attr - OPTEE_MSG_ATTR_TYPE_TMEM_INPUT; + p->u.memref.size = mp->u.tmem.size; + shm = (struct tee_shm *)(unsigned long) + mp->u.tmem.shm_ref; + if (!shm) { + p->u.memref.shm_offs = 0; + p->u.memref.shm = NULL; + break; + } + rc = tee_shm_get_pa(shm, 0, &pa); + if (rc) + return rc; + p->u.memref.shm_offs = mp->u.tmem.buf_ptr - pa; + p->u.memref.shm = shm; + + /* Check that the memref is covered by the shm object */ + if (p->u.memref.size) { + size_t o = p->u.memref.shm_offs + + p->u.memref.size - 1; + + rc = tee_shm_get_pa(shm, o, NULL); + if (rc) + return rc; + } + break; + default: + return -EINVAL; + } + } + return 0; +} + +/** + * optee_to_msg_param() - convert from struct tee_params to OPTEE_MSG parameters + * @msg_params: OPTEE_MSG parameters + * @num_params: number of elements in the parameter arrays + * @params: subsystem itnernal parameter representation + * Returns 0 on success or <0 on failure + */ +int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params, + const struct tee_param *params) +{ + int rc; + size_t n; + phys_addr_t pa; + + for (n = 0; n < num_params; n++) { + const struct tee_param *p = params + n; + struct optee_msg_param *mp = msg_params + n; + + switch (p->attr) { + case TEE_IOCTL_PARAM_ATTR_TYPE_NONE: + mp->attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE; + memset(&mp->u, 0, sizeof(mp->u)); + break; + case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INOUT: + mp->attr = OPTEE_MSG_ATTR_TYPE_VALUE_INPUT + p->attr - + TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_INPUT; + mp->u.value.a = p->u.value.a; + mp->u.value.b = p->u.value.b; + mp->u.value.c = p->u.value.c; + break; + case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_OUTPUT: + case TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT: + mp->attr = OPTEE_MSG_ATTR_TYPE_TMEM_INPUT + + p->attr - + TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT; + mp->u.tmem.shm_ref = (unsigned long)p->u.memref.shm; + mp->u.tmem.size = p->u.memref.size; + if (!p->u.memref.shm) { + mp->u.tmem.buf_ptr = 0; + break; + } + rc = tee_shm_get_pa(p->u.memref.shm, + p->u.memref.shm_offs, &pa); + if (rc) + return rc; + mp->u.tmem.buf_ptr = pa; + mp->attr |= OPTEE_MSG_ATTR_CACHE_PREDEFINED << + OPTEE_MSG_ATTR_CACHE_SHIFT; + break; + default: + return -EINVAL; + } + } + return 0; +} + +static void optee_get_version(struct tee_device *teedev, + struct tee_ioctl_version_data *vers) +{ + struct tee_ioctl_version_data v = { + .impl_id = TEE_IMPL_ID_OPTEE, + .impl_caps = TEE_OPTEE_CAP_TZ, + .gen_caps = TEE_GEN_CAP_GP, + }; + *vers = v; +} + +static int optee_open(struct tee_context *ctx) +{ + struct optee_context_data *ctxdata; + struct tee_device *teedev = ctx->teedev; + struct optee *optee = tee_get_drvdata(teedev); + + ctxdata = kzalloc(sizeof(*ctxdata), GFP_KERNEL); + if (!ctxdata) + return -ENOMEM; + + if (teedev == optee->supp_teedev) { + bool busy = true; + + mutex_lock(&optee->supp.ctx_mutex); + if (!optee->supp.ctx) { + busy = false; + optee->supp.ctx = ctx; + } + mutex_unlock(&optee->supp.ctx_mutex); + if (busy) { + kfree(ctxdata); + return -EBUSY; + } + } + + mutex_init(&ctxdata->mutex); + INIT_LIST_HEAD(&ctxdata->sess_list); + + ctx->data = ctxdata; + return 0; +} + +static void optee_release(struct tee_context *ctx) +{ + struct optee_context_data *ctxdata = ctx->data; + struct tee_device *teedev = ctx->teedev; + struct optee *optee = tee_get_drvdata(teedev); + struct tee_shm *shm; + struct optee_msg_arg *arg = NULL; + phys_addr_t parg; + struct optee_session *sess; + struct optee_session *sess_tmp; + + if (!ctxdata) + return; + + shm = tee_shm_alloc(ctx, sizeof(struct optee_msg_arg), TEE_SHM_MAPPED); + if (!IS_ERR(shm)) { + arg = tee_shm_get_va(shm, 0); + /* + * If va2pa fails for some reason, we can't call + * optee_close_session(), only free the memory. Secure OS + * will leak sessions and finally refuse more sessions, but + * we will at least let normal world reclaim its memory. + */ + if (!IS_ERR(arg)) + tee_shm_va2pa(shm, arg, &parg); + } + + list_for_each_entry_safe(sess, sess_tmp, &ctxdata->sess_list, + list_node) { + list_del(&sess->list_node); + if (!IS_ERR_OR_NULL(arg)) { + memset(arg, 0, sizeof(*arg)); + arg->cmd = OPTEE_MSG_CMD_CLOSE_SESSION; + arg->session = sess->session_id; + optee_do_call_with_arg(ctx, parg); + } + kfree(sess); + } + kfree(ctxdata); + + if (!IS_ERR(shm)) + tee_shm_free(shm); + + ctx->data = NULL; + + if (teedev == optee->supp_teedev) { + mutex_lock(&optee->supp.ctx_mutex); + optee->supp.ctx = NULL; + mutex_unlock(&optee->supp.ctx_mutex); + } +} + +static struct tee_driver_ops optee_ops = { + .get_version = optee_get_version, + .open = optee_open, + .release = optee_release, + .open_session = optee_open_session, + .close_session = optee_close_session, + .invoke_func = optee_invoke_func, + .cancel_req = optee_cancel_req, +}; + +static struct tee_desc optee_desc = { + .name = DRIVER_NAME "-clnt", + .ops = &optee_ops, + .owner = THIS_MODULE, +}; + +static struct tee_driver_ops optee_supp_ops = { + .get_version = optee_get_version, + .open = optee_open, + .release = optee_release, + .supp_recv = optee_supp_recv, + .supp_send = optee_supp_send, +}; + +static struct tee_desc optee_supp_desc = { + .name = DRIVER_NAME "-supp", + .ops = &optee_supp_ops, + .owner = THIS_MODULE, + .flags = TEE_DESC_PRIVILEGED, +}; + +static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn) +{ + struct arm_smccc_res res; + + invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res); + + if (res.a0 == OPTEE_MSG_UID_0 && res.a1 == OPTEE_MSG_UID_1 && + res.a2 == OPTEE_MSG_UID_2 && res.a3 == OPTEE_MSG_UID_3) + return true; + return false; +} + +static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_calls_revision_result result; + } res; + + invoke_fn(OPTEE_SMC_CALLS_REVISION, 0, 0, 0, 0, 0, 0, 0, &res.smccc); + + if (res.result.major == OPTEE_MSG_REVISION_MAJOR && + (int)res.result.minor >= OPTEE_MSG_REVISION_MINOR) + return true; + return false; +} + +static bool optee_msg_exchange_capabilities(optee_invoke_fn *invoke_fn, + u32 *sec_caps) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_exchange_capabilities_result result; + } res; + u32 a1 = 0; + + /* + * TODO This isn't enough to tell if it's UP system (from kernel + * point of view) or not, is_smp() returns the the information + * needed, but can't be called directly from here. + */ + if (!IS_ENABLED(CONFIG_SMP) || nr_cpu_ids == 1) + a1 |= OPTEE_SMC_NSEC_CAP_UNIPROCESSOR; + + invoke_fn(OPTEE_SMC_EXCHANGE_CAPABILITIES, a1, 0, 0, 0, 0, 0, 0, + &res.smccc); + + if (res.result.status != OPTEE_SMC_RETURN_OK) + return false; + + *sec_caps = res.result.capabilities; + return true; +} + +static struct tee_shm_pool * +optee_config_shm_memremap(optee_invoke_fn *invoke_fn, void **memremaped_shm) +{ + union { + struct arm_smccc_res smccc; + struct optee_smc_get_shm_config_result result; + } res; + struct tee_shm_pool *pool; + unsigned long vaddr; + phys_addr_t paddr; + size_t size; + phys_addr_t begin; + phys_addr_t end; + void *va; + struct tee_shm_pool_mem_info priv_info; + struct tee_shm_pool_mem_info dmabuf_info; + + invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc); + if (res.result.status != OPTEE_SMC_RETURN_OK) { + pr_info("shm service not available\n"); + return ERR_PTR(-ENOENT); + } + + if (res.result.settings != OPTEE_SMC_SHM_CACHED) { + pr_err("only normal cached shared memory supported\n"); + return ERR_PTR(-EINVAL); + } + + begin = roundup(res.result.start, PAGE_SIZE); + end = rounddown(res.result.start + res.result.size, PAGE_SIZE); + paddr = begin; + size = end - begin; + + if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) { + pr_err("too small shared memory area\n"); + return ERR_PTR(-EINVAL); + } + + va = memremap(paddr, size, MEMREMAP_WB); + if (!va) { + pr_err("shared memory ioremap failed\n"); + return ERR_PTR(-EINVAL); + } + vaddr = (unsigned long)va; + + priv_info.vaddr = vaddr; + priv_info.paddr = paddr; + priv_info.size = OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE; + dmabuf_info.vaddr = vaddr + OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE; + dmabuf_info.paddr = paddr + OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE; + dmabuf_info.size = size - OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE; + + pool = tee_shm_pool_alloc_res_mem(&priv_info, &dmabuf_info); + if (IS_ERR(pool)) { + memunmap(va); + goto out; + } + + *memremaped_shm = va; +out: + return pool; +} + +/* Simple wrapper functions to be able to use a function pointer */ +static void optee_smccc_smc(unsigned long a0, unsigned long a1, + unsigned long a2, unsigned long a3, + unsigned long a4, unsigned long a5, + unsigned long a6, unsigned long a7, + struct arm_smccc_res *res) +{ + arm_smccc_smc(a0, a1, a2, a3, a4, a5, a6, a7, res); +} + +static void optee_smccc_hvc(unsigned long a0, unsigned long a1, + unsigned long a2, unsigned long a3, + unsigned long a4, unsigned long a5, + unsigned long a6, unsigned long a7, + struct arm_smccc_res *res) +{ + arm_smccc_hvc(a0, a1, a2, a3, a4, a5, a6, a7, res); +} + +static optee_invoke_fn *get_invoke_func(struct device_node *np) +{ + const char *method; + + pr_info("probing for conduit method from DT.\n"); + + if (of_property_read_string(np, "method", &method)) { + pr_warn("missing \"method\" property\n"); + return ERR_PTR(-ENXIO); + } + + if (!strcmp("hvc", method)) + return optee_smccc_hvc; + else if (!strcmp("smc", method)) + return optee_smccc_smc; + + pr_warn("invalid \"method\" property: %s\n", method); + return ERR_PTR(-EINVAL); +} + +static struct optee *optee_probe(struct device_node *np) +{ + optee_invoke_fn *invoke_fn; + struct tee_shm_pool *pool; + struct optee *optee = NULL; + void *memremaped_shm = NULL; + struct tee_device *teedev; + u32 sec_caps; + int rc; + + invoke_fn = get_invoke_func(np); + if (IS_ERR(invoke_fn)) + return (void *)invoke_fn; + + if (!optee_msg_api_uid_is_optee_api(invoke_fn)) { + pr_warn("api uid mismatch\n"); + return ERR_PTR(-EINVAL); + } + + if (!optee_msg_api_revision_is_compatible(invoke_fn)) { + pr_warn("api revision mismatch\n"); + return ERR_PTR(-EINVAL); + } + + if (!optee_msg_exchange_capabilities(invoke_fn, &sec_caps)) { + pr_warn("capabilities mismatch\n"); + return ERR_PTR(-EINVAL); + } + + /* + * We have no other option for shared memory, if secure world + * doesn't have any reserved memory we can use we can't continue. + */ + if (!(sec_caps & OPTEE_SMC_SEC_CAP_HAVE_RESERVED_SHM)) + return ERR_PTR(-EINVAL); + + pool = optee_config_shm_memremap(invoke_fn, &memremaped_shm); + if (IS_ERR(pool)) + return (void *)pool; + + optee = kzalloc(sizeof(*optee), GFP_KERNEL); + if (!optee) { + rc = -ENOMEM; + goto err; + } + + optee->invoke_fn = invoke_fn; + + teedev = tee_device_alloc(&optee_desc, NULL, pool, optee); + if (IS_ERR(teedev)) { + rc = PTR_ERR(teedev); + goto err; + } + optee->teedev = teedev; + + teedev = tee_device_alloc(&optee_supp_desc, NULL, pool, optee); + if (IS_ERR(teedev)) { + rc = PTR_ERR(teedev); + goto err; + } + optee->supp_teedev = teedev; + + rc = tee_device_register(optee->teedev); + if (rc) + goto err; + + rc = tee_device_register(optee->supp_teedev); + if (rc) + goto err; + + mutex_init(&optee->call_queue.mutex); + INIT_LIST_HEAD(&optee->call_queue.waiters); + optee_wait_queue_init(&optee->wait_queue); + optee_supp_init(&optee->supp); + optee->memremaped_shm = memremaped_shm; + optee->pool = pool; + + optee_enable_shm_cache(optee); + + pr_info("initialized driver\n"); + return optee; +err: + if (optee) { + /* + * tee_device_unregister() is safe to call even if the + * devices hasn't been registered with + * tee_device_register() yet. + */ + tee_device_unregister(optee->supp_teedev); + tee_device_unregister(optee->teedev); + kfree(optee); + } + if (pool) + tee_shm_pool_free(pool); + if (memremaped_shm) + memunmap(memremaped_shm); + return ERR_PTR(rc); +} + +static void optee_remove(struct optee *optee) +{ + /* + * Ask OP-TEE to free all cached shared memory objects to decrease + * reference counters and also avoid wild pointers in secure world + * into the old shared memory range. + */ + optee_disable_shm_cache(optee); + + /* + * The two devices has to be unregistered before we can free the + * other resources. + */ + tee_device_unregister(optee->supp_teedev); + tee_device_unregister(optee->teedev); + + tee_shm_pool_free(optee->pool); + if (optee->memremaped_shm) + memunmap(optee->memremaped_shm); + optee_wait_queue_exit(&optee->wait_queue); + optee_supp_uninit(&optee->supp); + mutex_destroy(&optee->call_queue.mutex); + + kfree(optee); +} + +static const struct of_device_id optee_match[] = { + { .compatible = "linaro,optee-tz" }, + {}, +}; + +static struct optee *optee_svc; + +static int __init optee_driver_init(void) +{ + struct device_node *fw_np; + struct device_node *np; + struct optee *optee; + + /* Node is supposed to be below /firmware */ + fw_np = of_find_node_by_name(NULL, "firmware"); + if (!fw_np) + return -ENODEV; + + np = of_find_matching_node(fw_np, optee_match); + of_node_put(fw_np); + if (!np) + return -ENODEV; + + optee = optee_probe(np); + of_node_put(np); + + if (IS_ERR(optee)) + return PTR_ERR(optee); + + optee_svc = optee; + + return 0; +} +module_init(optee_driver_init); + +static void __exit optee_driver_exit(void) +{ + struct optee *optee = optee_svc; + + optee_svc = NULL; + if (optee) + optee_remove(optee); +} +module_exit(optee_driver_exit); + +MODULE_AUTHOR("Linaro"); +MODULE_DESCRIPTION("OP-TEE driver"); +MODULE_SUPPORTED_DEVICE(""); +MODULE_VERSION("1.0"); +MODULE_LICENSE("GPL v2"); |