From patchwork Sat Jan 27 23:14:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gaurav Kashyap \(QUIC\)" X-Patchwork-Id: 766967 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 48B0D20DD1; Sat, 27 Jan 2024 23:27:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.180.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706398029; cv=none; b=JWbhb/dCTZiK8dTjWw6vdijTuUgQ7PGHP2URUo9yrCdnHV/yxTkWnhghXFn7J2iAFrncWK/uqIKxeZrTLylH5gNZwC2ATi2NH/FyZ0FBhUwgbGL2gdsATEFPh41s8K1G8hi5e94/7+hPW/erEVBXoRJE9+6ll0MOJBslBnQpevg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706398029; c=relaxed/simple; bh=DoC26Zth7EMRgUeXiBNSQ/5UKrMl1Jy4RtBM1jTsoGE=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=uCBH4d2ISfFdR/F+IGaOV+FO72BClWi/xSKp/6fyHTpuj0Rfrv/ScQtRqeoS6nnrV5S9H7Ri/8iqSF03aRGyVVVe/bi+eh0vyp6CKvQc6FK4qUB/d+qKmD+BgnbPsPZ54E5VQJX35XpcqI0AZIhQcnRxJxGHPrBn2j/O65K+5wY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=m91E/7vp; arc=none smtp.client-ip=205.220.180.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="m91E/7vp" Received: from pps.filterd (m0279871.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.24/8.17.1.24) with ESMTP id 40RNGBPO000738; Sat, 27 Jan 2024 23:26:22 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding:content-type; s= qcppdkim1; bh=dZsbikU7IrJRDi/3lw/414IWmaPQrY5eY3TdobIUbpQ=; b=m9 1E/7vpwmCGa4yBxjQS7foexZFt6R1lv+xaKf497pEf1+t1DVJx4cSHq0FxGECZWW nd3pGor1cr4wjGEimQwnR9yKU2NqSD8c1bp42obS5GW4x4CDC9xcYfqK7uiv2OxM LiDlMSqyBMp7sbcHNXqefEwCZjpSTan2gbTAr1BmHabhTNsQO9FOnNlmexbmHgdu 254b1gN84MQMOmgNuyUBqicmnPvv83uOVZ+on/BkGxEwgNAOsnyhEzMEbwIuiRtH dYsQHhGGTGIvDzQJzHXPqvUtsFWVDiAwharxj5CnsRHJjV433TMRiSnT/EAu/csO 4qkFRqosUMAvYAgn00Dw== Received: from nalasppmta05.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3vvse4s53y-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 27 Jan 2024 23:26:21 +0000 (GMT) Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA05.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 40RNQKbo010233 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 27 Jan 2024 23:26:20 GMT Received: from hu-gaurkash-lv.qualcomm.com (10.49.16.6) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Sat, 27 Jan 2024 15:26:16 -0800 From: Gaurav Kashyap To: , , , , , , , , CC: , , , , , , , , , , , , , , , Gaurav Kashyap Subject: [PATCH v4 02/15] qcom_scm: scm call for deriving a software secret Date: Sat, 27 Jan 2024 15:14:00 -0800 Message-ID: <20240127232436.2632187-3-quic_gaurkash@quicinc.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240127232436.2632187-1-quic_gaurkash@quicinc.com> References: <20240127232436.2632187-1-quic_gaurkash@quicinc.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nalasex01c.na.qualcomm.com (10.47.97.35) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: 2yhUtWzVvm9Biu1q3n5mL9oP-zvLvn4K X-Proofpoint-GUID: 2yhUtWzVvm9Biu1q3n5mL9oP-zvLvn4K X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2024-01-25_14,2024-01-25_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 spamscore=0 malwarescore=0 priorityscore=1501 bulkscore=0 phishscore=0 mlxlogscore=984 impostorscore=0 lowpriorityscore=0 suspectscore=0 adultscore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2401190000 definitions=main-2401270178 Inline storage encryption may require deriving a software secret from storage keys added to the kernel. For non-wrapped keys, this can be directly done in the kernel as keys are in the clear. However, hardware wrapped keys can only be unwrapped by the wrapping entity. In case of Qualcomm's wrapped key solution, this is done by the Hardware Key Manager (HWKM) from Trustzone. Hence, adding a new SCM call which in the end provides a hook to the software secret crypto profile API provided by the block layer. Signed-off-by: Gaurav Kashyap Tested-by: Neil Armstrong --- drivers/firmware/qcom/qcom_scm.c | 65 ++++++++++++++++++++++++++ drivers/firmware/qcom/qcom_scm.h | 1 + include/linux/firmware/qcom/qcom_scm.h | 2 + 3 files changed, 68 insertions(+) diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c index 7e17fd662bda..4882f8a36453 100644 --- a/drivers/firmware/qcom/qcom_scm.c +++ b/drivers/firmware/qcom/qcom_scm.c @@ -1220,6 +1220,71 @@ int qcom_scm_ice_set_key(u32 index, const u8 *key, u32 key_size, } EXPORT_SYMBOL_GPL(qcom_scm_ice_set_key); +/** + * qcom_scm_derive_sw_secret() - Derive software secret from wrapped key + * @wkey: the hardware wrapped key inaccessible to software + * @wkey_size: size of the wrapped key + * @sw_secret: the secret to be derived which is exactly the secret size + * @sw_secret_size: size of the sw_secret + * + * Derive a software secret from a hardware wrapped key for software crypto + * operations. + * For wrapped keys, the key needs to be unwrapped, in order to derive a + * software secret, which can be done in the hardware from a secure execution + * environment. + * + * For more information on sw secret, please refer to "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 *wkey, size_t wkey_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), + .args[1] = wkey_size, + .args[3] = sw_secret_size, + .owner = ARM_SMCCC_OWNER_SIP, + }; + + void *secret_buf; + void *wkey_buf; + int ret; + + wkey_buf = qcom_tzmem_alloc(__scm->mempool, wkey_size, GFP_KERNEL); + if (!wkey_buf) + return -ENOMEM; + + secret_buf = qcom_tzmem_alloc(__scm->mempool, sw_secret_size, GFP_KERNEL); + if (!secret_buf) { + ret = -ENOMEM; + goto err_free_wrapped; + } + + memcpy(wkey_buf, wkey, wkey_size); + desc.args[0] = qcom_tzmem_to_phys(wkey_buf); + desc.args[2] = qcom_tzmem_to_phys(secret_buf); + + ret = qcom_scm_call(__scm->dev, &desc, NULL); + if (!ret) + memcpy(sw_secret, secret_buf, sw_secret_size); + + memzero_explicit(secret_buf, sw_secret_size); + qcom_tzmem_free(secret_buf); + +err_free_wrapped: + memzero_explicit(wkey_buf, wkey_size); + qcom_tzmem_free(wkey_buf); + + return ret; +} +EXPORT_SYMBOL_GPL(qcom_scm_derive_sw_secret); + /** * qcom_scm_hdcp_available() - Check if secure environment supports HDCP. * diff --git a/drivers/firmware/qcom/qcom_scm.h b/drivers/firmware/qcom/qcom_scm.h index cb7273aa0a5e..56ff0806f5d2 100644 --- a/drivers/firmware/qcom/qcom_scm.h +++ b/drivers/firmware/qcom/qcom_scm.h @@ -127,6 +127,7 @@ struct qcom_tzmem_pool *qcom_scm_get_tzmem_pool(void); #define QCOM_SCM_SVC_ES 0x10 /* Enterprise Security */ #define QCOM_SCM_ES_INVALIDATE_ICE_KEY 0x03 #define QCOM_SCM_ES_CONFIG_SET_ICE_KEY 0x04 +#define QCOM_SCM_ES_DERIVE_SW_SECRET 0x07 #define QCOM_SCM_SVC_HDCP 0x11 #define QCOM_SCM_HDCP_INVOKE 0x01 diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h index 9b6054813f59..89358478ac67 100644 --- a/include/linux/firmware/qcom/qcom_scm.h +++ b/include/linux/firmware/qcom/qcom_scm.h @@ -103,6 +103,8 @@ bool qcom_scm_ice_available(void); int qcom_scm_ice_invalidate_key(u32 index); int qcom_scm_ice_set_key(u32 index, const u8 *key, u32 key_size, enum qcom_scm_ice_cipher cipher, u32 data_unit_size); +int qcom_scm_derive_sw_secret(const u8 *wkey, size_t wkey_size, + u8 *sw_secret, size_t sw_secret_size); bool qcom_scm_hdcp_available(void); int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt, u32 *resp);