diff options
Diffstat (limited to 'drivers/firmware/qcom/qcom_scm.c')
-rw-r--r-- | drivers/firmware/qcom/qcom_scm.c | 271 |
1 files changed, 255 insertions, 16 deletions
diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c index 72bf87ddcd96..fc4d67e4c4a6 100644 --- a/drivers/firmware/qcom/qcom_scm.c +++ b/drivers/firmware/qcom/qcom_scm.c @@ -217,7 +217,10 @@ static DEFINE_SPINLOCK(scm_query_lock); struct qcom_tzmem_pool *qcom_scm_get_tzmem_pool(void) { - return __scm ? __scm->mempool : NULL; + if (!qcom_scm_is_available()) + return NULL; + + return __scm->mempool; } static enum qcom_scm_convention __get_convention(void) @@ -1279,6 +1282,220 @@ int qcom_scm_ice_set_key(u32 index, const u8 *key, u32 key_size, } EXPORT_SYMBOL_GPL(qcom_scm_ice_set_key); +bool qcom_scm_has_wrapped_key_support(void) +{ + return __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_ES, + QCOM_SCM_ES_DERIVE_SW_SECRET) && + __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_ES, + QCOM_SCM_ES_GENERATE_ICE_KEY) && + __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_ES, + QCOM_SCM_ES_PREPARE_ICE_KEY) && + __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_ES, + QCOM_SCM_ES_IMPORT_ICE_KEY); +} +EXPORT_SYMBOL_GPL(qcom_scm_has_wrapped_key_support); + +/** + * qcom_scm_derive_sw_secret() - Derive software secret from wrapped key + * @eph_key: an ephemerally-wrapped key + * @eph_key_size: size of @eph_key in bytes + * @sw_secret: output buffer for the software secret + * @sw_secret_size: size of the software secret to derive in bytes + * + * Derive a software secret from an ephemerally-wrapped key for software crypto + * operations. This is done by calling into the secure execution environment, + * which then calls into the hardware to unwrap and derive the secret. + * + * For more information on sw_secret, see the "Hardware-wrapped keys" section of + * Documentation/block/inline-encryption.rst. + * + * Return: 0 on success; -errno on failure. + */ +int qcom_scm_derive_sw_secret(const u8 *eph_key, size_t eph_key_size, + u8 *sw_secret, size_t sw_secret_size) +{ + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_ES, + .cmd = QCOM_SCM_ES_DERIVE_SW_SECRET, + .arginfo = QCOM_SCM_ARGS(4, QCOM_SCM_RW, QCOM_SCM_VAL, + QCOM_SCM_RW, QCOM_SCM_VAL), + .owner = ARM_SMCCC_OWNER_SIP, + }; + int ret; + + void *eph_key_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + eph_key_size, + GFP_KERNEL); + if (!eph_key_buf) + return -ENOMEM; + + void *sw_secret_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + sw_secret_size, + GFP_KERNEL); + if (!sw_secret_buf) + return -ENOMEM; + + memcpy(eph_key_buf, eph_key, eph_key_size); + desc.args[0] = qcom_tzmem_to_phys(eph_key_buf); + desc.args[1] = eph_key_size; + desc.args[2] = qcom_tzmem_to_phys(sw_secret_buf); + desc.args[3] = sw_secret_size; + + ret = qcom_scm_call(__scm->dev, &desc, NULL); + if (!ret) + memcpy(sw_secret, sw_secret_buf, sw_secret_size); + + memzero_explicit(eph_key_buf, eph_key_size); + memzero_explicit(sw_secret_buf, sw_secret_size); + return ret; +} +EXPORT_SYMBOL_GPL(qcom_scm_derive_sw_secret); + +/** + * qcom_scm_generate_ice_key() - Generate a wrapped key for storage encryption + * @lt_key: output buffer for the long-term wrapped key + * @lt_key_size: size of @lt_key in bytes. Must be the exact wrapped key size + * used by the SoC. + * + * Generate a key using the built-in HW module in the SoC. The resulting key is + * returned wrapped with the platform-specific Key Encryption Key. + * + * Return: 0 on success; -errno on failure. + */ +int qcom_scm_generate_ice_key(u8 *lt_key, size_t lt_key_size) +{ + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_ES, + .cmd = QCOM_SCM_ES_GENERATE_ICE_KEY, + .arginfo = QCOM_SCM_ARGS(2, QCOM_SCM_RW, QCOM_SCM_VAL), + .owner = ARM_SMCCC_OWNER_SIP, + }; + int ret; + + void *lt_key_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + lt_key_size, + GFP_KERNEL); + if (!lt_key_buf) + return -ENOMEM; + + desc.args[0] = qcom_tzmem_to_phys(lt_key_buf); + desc.args[1] = lt_key_size; + + ret = qcom_scm_call(__scm->dev, &desc, NULL); + if (!ret) + memcpy(lt_key, lt_key_buf, lt_key_size); + + memzero_explicit(lt_key_buf, lt_key_size); + return ret; +} +EXPORT_SYMBOL_GPL(qcom_scm_generate_ice_key); + +/** + * qcom_scm_prepare_ice_key() - Re-wrap a key with the per-boot ephemeral key + * @lt_key: a long-term wrapped key + * @lt_key_size: size of @lt_key in bytes + * @eph_key: output buffer for the ephemerally-wrapped key + * @eph_key_size: size of @eph_key in bytes. Must be the exact wrapped key size + * used by the SoC. + * + * Given a long-term wrapped key, re-wrap it with the per-boot ephemeral key for + * added protection. The resulting key will only be valid for the current boot. + * + * Return: 0 on success; -errno on failure. + */ +int qcom_scm_prepare_ice_key(const u8 *lt_key, size_t lt_key_size, + u8 *eph_key, size_t eph_key_size) +{ + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_ES, + .cmd = QCOM_SCM_ES_PREPARE_ICE_KEY, + .arginfo = QCOM_SCM_ARGS(4, QCOM_SCM_RO, QCOM_SCM_VAL, + QCOM_SCM_RW, QCOM_SCM_VAL), + .owner = ARM_SMCCC_OWNER_SIP, + }; + int ret; + + void *lt_key_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + lt_key_size, + GFP_KERNEL); + if (!lt_key_buf) + return -ENOMEM; + + void *eph_key_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + eph_key_size, + GFP_KERNEL); + if (!eph_key_buf) + return -ENOMEM; + + memcpy(lt_key_buf, lt_key, lt_key_size); + desc.args[0] = qcom_tzmem_to_phys(lt_key_buf); + desc.args[1] = lt_key_size; + desc.args[2] = qcom_tzmem_to_phys(eph_key_buf); + desc.args[3] = eph_key_size; + + ret = qcom_scm_call(__scm->dev, &desc, NULL); + if (!ret) + memcpy(eph_key, eph_key_buf, eph_key_size); + + memzero_explicit(lt_key_buf, lt_key_size); + memzero_explicit(eph_key_buf, eph_key_size); + return ret; +} +EXPORT_SYMBOL_GPL(qcom_scm_prepare_ice_key); + +/** + * qcom_scm_import_ice_key() - Import key for storage encryption + * @raw_key: the raw key to import + * @raw_key_size: size of @raw_key in bytes + * @lt_key: output buffer for the long-term wrapped key + * @lt_key_size: size of @lt_key in bytes. Must be the exact wrapped key size + * used by the SoC. + * + * Import a raw key and return a long-term wrapped key. Uses the SoC's HWKM to + * wrap the raw key using the platform-specific Key Encryption Key. + * + * Return: 0 on success; -errno on failure. + */ +int qcom_scm_import_ice_key(const u8 *raw_key, size_t raw_key_size, + u8 *lt_key, size_t lt_key_size) +{ + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_ES, + .cmd = QCOM_SCM_ES_IMPORT_ICE_KEY, + .arginfo = QCOM_SCM_ARGS(4, QCOM_SCM_RO, QCOM_SCM_VAL, + QCOM_SCM_RW, QCOM_SCM_VAL), + .owner = ARM_SMCCC_OWNER_SIP, + }; + int ret; + + void *raw_key_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + raw_key_size, + GFP_KERNEL); + if (!raw_key_buf) + return -ENOMEM; + + void *lt_key_buf __free(qcom_tzmem) = qcom_tzmem_alloc(__scm->mempool, + lt_key_size, + GFP_KERNEL); + if (!lt_key_buf) + return -ENOMEM; + + memcpy(raw_key_buf, raw_key, raw_key_size); + desc.args[0] = qcom_tzmem_to_phys(raw_key_buf); + desc.args[1] = raw_key_size; + desc.args[2] = qcom_tzmem_to_phys(lt_key_buf); + desc.args[3] = lt_key_size; + + ret = qcom_scm_call(__scm->dev, &desc, NULL); + if (!ret) + memcpy(lt_key, lt_key_buf, lt_key_size); + + memzero_explicit(raw_key_buf, raw_key_size); + memzero_explicit(lt_key_buf, lt_key_size); + return ret; +} +EXPORT_SYMBOL_GPL(qcom_scm_import_ice_key); + /** * qcom_scm_hdcp_available() - Check if secure environment supports HDCP. * @@ -1768,18 +1985,23 @@ EXPORT_SYMBOL_GPL(qcom_scm_qseecom_app_send); + any potential issues with this, only allow validated machines for now. */ static const struct of_device_id qcom_scm_qseecom_allowlist[] __maybe_unused = { + { .compatible = "asus,vivobook-s15" }, { .compatible = "dell,xps13-9345" }, + { .compatible = "hp,omnibook-x14" }, + { .compatible = "huawei,gaokun3" }, { .compatible = "lenovo,flex-5g" }, { .compatible = "lenovo,thinkpad-t14s" }, { .compatible = "lenovo,thinkpad-x13s", }, { .compatible = "lenovo,yoga-slim7x" }, { .compatible = "microsoft,arcata", }, + { .compatible = "microsoft,blackrock" }, { .compatible = "microsoft,romulus13", }, { .compatible = "microsoft,romulus15", }, { .compatible = "qcom,sc8180x-primus" }, { .compatible = "qcom,x1e001de-devkit" }, { .compatible = "qcom,x1e80100-crd" }, { .compatible = "qcom,x1e80100-qcp" }, + { .compatible = "qcom,x1p42100-crd" }, { } }; @@ -1867,7 +2089,8 @@ static int qcom_scm_qseecom_init(struct qcom_scm *scm) */ bool qcom_scm_is_available(void) { - return !!READ_ONCE(__scm); + /* Paired with smp_store_release() in qcom_scm_probe */ + return !!smp_load_acquire(&__scm); } EXPORT_SYMBOL_GPL(qcom_scm_is_available); @@ -2024,18 +2247,22 @@ static int qcom_scm_probe(struct platform_device *pdev) if (ret) return ret; - /* Let all above stores be available after this */ + /* Paired with smp_load_acquire() in qcom_scm_is_available(). */ smp_store_release(&__scm, scm); irq = platform_get_irq_optional(pdev, 0); if (irq < 0) { - if (irq != -ENXIO) - return irq; + if (irq != -ENXIO) { + ret = irq; + goto err; + } } else { ret = devm_request_threaded_irq(__scm->dev, irq, NULL, qcom_scm_irq_handler, IRQF_ONESHOT, "qcom-scm", __scm); - if (ret < 0) - return dev_err_probe(scm->dev, ret, "Failed to request qcom-scm irq\n"); + if (ret < 0) { + dev_err_probe(scm->dev, ret, "Failed to request qcom-scm irq\n"); + goto err; + } } __get_convention(); @@ -2054,14 +2281,18 @@ static int qcom_scm_probe(struct platform_device *pdev) qcom_scm_disable_sdi(); ret = of_reserved_mem_device_init(__scm->dev); - if (ret && ret != -ENODEV) - return dev_err_probe(__scm->dev, ret, - "Failed to setup the reserved memory region for TZ mem\n"); + if (ret && ret != -ENODEV) { + dev_err_probe(__scm->dev, ret, + "Failed to setup the reserved memory region for TZ mem\n"); + goto err; + } ret = qcom_tzmem_enable(__scm->dev); - if (ret) - return dev_err_probe(__scm->dev, ret, - "Failed to enable the TrustZone memory allocator\n"); + if (ret) { + dev_err_probe(__scm->dev, ret, + "Failed to enable the TrustZone memory allocator\n"); + goto err; + } memset(&pool_config, 0, sizeof(pool_config)); pool_config.initial_size = 0; @@ -2069,9 +2300,11 @@ static int qcom_scm_probe(struct platform_device *pdev) pool_config.max_size = SZ_256K; __scm->mempool = devm_qcom_tzmem_pool_new(__scm->dev, &pool_config); - if (IS_ERR(__scm->mempool)) - return dev_err_probe(__scm->dev, PTR_ERR(__scm->mempool), - "Failed to create the SCM memory pool\n"); + if (IS_ERR(__scm->mempool)) { + ret = dev_err_probe(__scm->dev, PTR_ERR(__scm->mempool), + "Failed to create the SCM memory pool\n"); + goto err; + } /* * Initialize the QSEECOM interface. @@ -2087,6 +2320,12 @@ static int qcom_scm_probe(struct platform_device *pdev) WARN(ret < 0, "failed to initialize qseecom: %d\n", ret); return 0; + +err: + /* Paired with smp_load_acquire() in qcom_scm_is_available(). */ + smp_store_release(&__scm, NULL); + + return ret; } static void qcom_scm_shutdown(struct platform_device *pdev) |