From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 EED712FBE01; Mon, 27 Oct 2025 09:51:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761558669; cv=none; b=DS6kz1axdfdd3nc6iOz1R50fxeV24JOPUNBHWod94uiO3Wouu96NJPnhgYIWpB4Owj8JNlZyWAfvAGld2vxsEj5hDMCoi0fCvjkeADJggal4pGkiiLMBR2NzmwalJ1WFxR7aw491ie0nvHYCb4CW88VV/S8UY5HiiRj1DukqI40= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761558669; c=relaxed/simple; bh=Af4vjbB3fxE+UHzJd2A7AwcGlqakMGAYFn/zD5eKCZI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=fcfp1B/J1tqnK3huvo1kF6w4Wrs19EEX2AO+LuusxQx/3WDrgfSeQPQEWHHdFlnCxYWKvKZ+6EJxgAyL4k8yeqWsrUKpqRDMkzY5sFg3ws1GDDYZDX0mf5KaWXLJeAMpzf9TJuQxA84TR1pP+97hf+SZmRQoc0oIhrX5Clmo840= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Eiayt2bE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Eiayt2bE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF4DFC19421; Mon, 27 Oct 2025 09:51:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761558668; bh=Af4vjbB3fxE+UHzJd2A7AwcGlqakMGAYFn/zD5eKCZI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Eiayt2bE9qQvGNsisE+w8aYJCdIU39z40VsuTS3f22ZU16cDEfhyM6VD423iXjGO7 4H4W1el4qZ47R5dmwViWXErODs66+H4s0l2H4y7hI/na0+Y4qTjHJJMEdOgjVF3owC fAw+Tjt4JIkDpL4OLcKrDxRDNZg7I5AGyCuOP+1XkYIhJcX4wW7ewA4I+FYusGMlgv SkpM5mSPoqjjKnWGNyeTpzmn9S+UkWLLd6PmuPq/MRXRXYULeNWmyM051aPMo8LUsr QV236VSfY7bgTYy6SG7MmuG1PQa3ECrhR9o/BTnfAtihMV6erRhRD7ATCrVB21jtAK V1oMVmftTMY2A== From: "Aneesh Kumar K.V (Arm)" To: linux-coco@lists.linux.dev, kvmarm@lists.linux.dev Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, dan.j.williams@intel.com, aik@amd.com, lukas@wunner.de, Samuel Ortiz , Xu Yilun , Jason Gunthorpe , Suzuki K Poulose , Steven Price , Bjorn Helgaas , Jonathan Cameron , Catalin Marinas , Marc Zyngier , Will Deacon , Oliver Upton , "Aneesh Kumar K.V (Arm)" Subject: [PATCH 12/12] coco: host: arm64: Register device public key with RMM Date: Mon, 27 Oct 2025 15:19:03 +0530 Message-ID: <20251027094916.1153143-12-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20251027094916.1153143-1-aneesh.kumar@kernel.org> References: <20251027094916.1153143-1-aneesh.kumar@kernel.org> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit - Introduce the SMC_RMI_PDEV_SET_PUBKEY helper and the associated struct rmi_public_key_params so the host can hand the device’s public key to the RMM. - Parse the certificate chain cached during IDE setup, extract the final certificate’s public key, and recognise RSA-3072, ECDSA-P256, and ECDSA-P384 keys before calling into the RMM. Signed-off-by: Aneesh Kumar K.V (Arm) --- arch/arm64/include/asm/rmi_cmds.h | 9 ++ arch/arm64/include/asm/rmi_smc.h | 18 +++ drivers/virt/coco/arm-cca-host/Kconfig | 4 + drivers/virt/coco/arm-cca-host/rmi-da.c | 166 +++++++++++++++++++++++- drivers/virt/coco/arm-cca-host/rmi-da.h | 1 + 5 files changed, 197 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/rmi_cmds.h b/arch/arm64/include/asm/rmi_cmds.h index f10a0dcaa308..339bea517760 100644 --- a/arch/arm64/include/asm/rmi_cmds.h +++ b/arch/arm64/include/asm/rmi_cmds.h @@ -574,4 +574,13 @@ static inline unsigned long rmi_pdev_destroy(unsigned long pdev_phys) return res.a0; } +static inline unsigned long rmi_pdev_set_pubkey(unsigned long pdev_phys, unsigned long key_phys) +{ + struct arm_smccc_res res; + + arm_smccc_1_1_invoke(SMC_RMI_PDEV_SET_PUBKEY, pdev_phys, key_phys, &res); + + return res.a0; +} + #endif /* __ASM_RMI_CMDS_H */ diff --git a/arch/arm64/include/asm/rmi_smc.h b/arch/arm64/include/asm/rmi_smc.h index 6eb6f7e4b77f..1f46e13b92a4 100644 --- a/arch/arm64/include/asm/rmi_smc.h +++ b/arch/arm64/include/asm/rmi_smc.h @@ -52,6 +52,7 @@ #define SMC_RMI_PDEV_CREATE SMC_RMI_CALL(0x0176) #define SMC_RMI_PDEV_DESTROY SMC_RMI_CALL(0x0177) #define SMC_RMI_PDEV_GET_STATE SMC_RMI_CALL(0x0178) +#define SMC_RMI_PDEV_SET_PUBKEY SMC_RMI_CALL(0x017b) #define SMC_RMI_PDEV_STOP SMC_RMI_CALL(0x017c) #define RMI_ABI_MAJOR_VERSION 1 @@ -426,4 +427,21 @@ struct rmi_dev_comm_data { }; }; +#define RMI_SIG_RSASSA_3072 0 +#define RMI_SIG_ECDSA_P256 1 +#define RMI_SIG_ECDSA_P384 2 + +struct rmi_public_key_params { + union { + struct { + u8 public_key[1024]; + u8 metadata[1024]; + u64 public_key_len; + u64 metadata_len; + u8 rmi_signature_algorithm; + } __packed; + u8 padding[0x1000]; + }; +}; + #endif /* __ASM_RMI_SMC_H */ diff --git a/drivers/virt/coco/arm-cca-host/Kconfig b/drivers/virt/coco/arm-cca-host/Kconfig index 1febd316fb77..efa66e960ad5 100644 --- a/drivers/virt/coco/arm-cca-host/Kconfig +++ b/drivers/virt/coco/arm-cca-host/Kconfig @@ -7,8 +7,12 @@ config ARM_CCA_HOST depends on ARM64 depends on PCI_TSM depends on KVM + select KEYS + select X509_CERTIFICATE_PARSER select TSM select AUXILIARY_BUS + select CRYPTO_ECDSA + select CRYPTO_RSA help ARM CCA RMM firmware is the trusted runtime that enforces memory diff --git a/drivers/virt/coco/arm-cca-host/rmi-da.c b/drivers/virt/coco/arm-cca-host/rmi-da.c index 644609618a7a..c9780ca64c17 100644 --- a/drivers/virt/coco/arm-cca-host/rmi-da.c +++ b/drivers/virt/coco/arm-cca-host/rmi-da.c @@ -8,6 +8,9 @@ #include #include #include +#include +#include +#include #include "rmi-da.h" @@ -361,6 +364,146 @@ static int do_pdev_communicate(struct pci_tsm *tsm, enum rmi_pdev_state target_s return do_dev_communicate(PDEV_COMMUNICATE, tsm, target_state, RMI_PDEV_ERROR); } +static int parse_certificate_chain(struct pci_tsm *tsm) +{ + struct cca_host_pf0_dsc *pf0_dsc; + unsigned int chain_size; + unsigned int offset = 0; + u8 *chain_data; + + pf0_dsc = to_cca_pf0_dsc(tsm->pdev); + + /* If device communication didn't results in certificate caching. */ + if (!pf0_dsc->cert_chain.cache || !pf0_dsc->cert_chain.cache->offset) + return -EINVAL; + + chain_size = pf0_dsc->cert_chain.cache->offset; + chain_data = pf0_dsc->cert_chain.cache->buf; + + while (offset < chain_size) { + ssize_t cert_len = + x509_get_certificate_length(chain_data + offset, + chain_size - offset); + if (cert_len < 0) + return cert_len; + + struct x509_certificate *cert __free(x509_free_certificate) = + x509_cert_parse(chain_data + offset, cert_len); + + if (IS_ERR(cert)) { + pci_warn(tsm->pdev, "parsing of certificate chain not successful\n"); + return PTR_ERR(cert); + } + + /* The key in the last cert in the chain is used */ + if (offset + cert_len == chain_size) { + pf0_dsc->cert_chain.public_key = kzalloc(cert->pub->keylen, GFP_KERNEL); + if (!pf0_dsc->cert_chain.public_key) + return -ENOMEM; + + if (!strcmp("ecdsa-nist-p256", cert->pub->pkey_algo)) { + pf0_dsc->rmi_signature_algorithm = RMI_SIG_ECDSA_P256; + } else if (!strcmp("ecdsa-nist-p384", cert->pub->pkey_algo)) { + pf0_dsc->rmi_signature_algorithm = RMI_SIG_ECDSA_P384; + } else if (!strcmp("rsa", cert->pub->pkey_algo)) { + pf0_dsc->rmi_signature_algorithm = RMI_SIG_RSASSA_3072; + } else { + kfree(pf0_dsc->cert_chain.public_key); + pf0_dsc->cert_chain.public_key = NULL; + return -ENXIO; + } + memcpy(pf0_dsc->cert_chain.public_key, cert->pub->key, cert->pub->keylen); + pf0_dsc->cert_chain.public_key_size = cert->pub->keylen; + } + + offset += cert_len; + } + + pf0_dsc->cert_chain.valid = true; + return 0; +} + +DEFINE_FREE(free_page, unsigned long, if (_T) free_page(_T)) +static int pdev_set_public_key(struct pci_tsm *tsm) +{ + unsigned long expected_key_len; + struct cca_host_pf0_dsc *pf0_dsc; + int ret; + + pf0_dsc = to_cca_pf0_dsc(tsm->pdev); + /* Check that all the necessary information was captured from communication */ + if (!pf0_dsc->cert_chain.valid) + return -EINVAL; + + struct rmi_public_key_params *key_params __free(free_page) = + (struct rmi_public_key_params *)get_zeroed_page(GFP_KERNEL); + if (!key_params) + return -ENOMEM; + + key_params->rmi_signature_algorithm = pf0_dsc->rmi_signature_algorithm; + + switch (key_params->rmi_signature_algorithm) { + case RMI_SIG_ECDSA_P384: + { + expected_key_len = 97; + + if (pf0_dsc->cert_chain.public_key_size != expected_key_len) + return -EINVAL; + + key_params->public_key_len = pf0_dsc->cert_chain.public_key_size; + memcpy(key_params->public_key, + pf0_dsc->cert_chain.public_key, + pf0_dsc->cert_chain.public_key_size); + key_params->metadata_len = 0; + break; + } + case RMI_SIG_ECDSA_P256: + { + expected_key_len = 65; + + if (pf0_dsc->cert_chain.public_key_size != expected_key_len) + return -EINVAL; + + key_params->public_key_len = pf0_dsc->cert_chain.public_key_size; + memcpy(key_params->public_key, + pf0_dsc->cert_chain.public_key, + pf0_dsc->cert_chain.public_key_size); + key_params->metadata_len = 0; + break; + } + case RMI_SIG_RSASSA_3072: + { + struct rsa_key rsa_key = {0}; + + expected_key_len = 385; + int ret_rsa_parse = rsa_parse_pub_key(&rsa_key, + pf0_dsc->cert_chain.public_key, + pf0_dsc->cert_chain.public_key_size); + /* This also checks the key_len */ + if (ret_rsa_parse) + return ret_rsa_parse; + /* + * exponent is usually 65537 (size = 24bits) but in rare cases + * the size can be as large as the modulus + */ + if (rsa_key.e_sz > expected_key_len) + return -EINVAL; + + key_params->public_key_len = rsa_key.n_sz; + key_params->metadata_len = rsa_key.e_sz; + memcpy(key_params->public_key, rsa_key.n, rsa_key.n_sz); + memcpy(key_params->metadata, rsa_key.e, rsa_key.e_sz); + break; + } + default: + return -EINVAL; + } + + ret = rmi_pdev_set_pubkey(virt_to_phys(pf0_dsc->rmm_pdev), + virt_to_phys(key_params)); + return ret; +} + void pdev_communicate_work(struct work_struct *work) { unsigned long state; @@ -410,7 +553,28 @@ static int submit_pdev_comm_work(struct pci_dev *pdev, int target_state) int pdev_ide_setup(struct pci_dev *pdev) { - return submit_pdev_comm_work(pdev, RMI_PDEV_NEEDS_KEY); + int ret; + + ret = submit_pdev_comm_work(pdev, RMI_PDEV_NEEDS_KEY); + if (ret) + return ret; + /* + * we now have certificate chain in dsm->cert_chain. Parse + * that and set the pubkey. + */ + ret = parse_certificate_chain(pdev->tsm); + if (ret) + return ret; + + ret = pdev_set_public_key(pdev->tsm); + if (ret) + return ret; + + ret = submit_pdev_comm_work(pdev, RMI_PDEV_READY); + if (ret) + return ret; + + return 0; } void pdev_stop_and_destroy(struct pci_dev *pdev) diff --git a/drivers/virt/coco/arm-cca-host/rmi-da.h b/drivers/virt/coco/arm-cca-host/rmi-da.h index e556ccecc1cb..f1a840b6d4fb 100644 --- a/drivers/virt/coco/arm-cca-host/rmi-da.h +++ b/drivers/virt/coco/arm-cca-host/rmi-da.h @@ -51,6 +51,7 @@ struct cca_host_pf0_dsc { int num_aux; void *aux[MAX_PDEV_AUX_GRANULES]; + uint8_t rmi_signature_algorithm; struct mutex object_lock; struct { struct cache_object *cache; -- 2.43.0