From: Brijesh Singh Subject: [Part2 PATCH v6.1 20/38] crypto: ccp: Implement SEV_PDH_CERT_EXPORT ioctl command Date: Mon, 23 Oct 2017 17:19:49 -0500 Message-ID: <20171023221949.47898-1-brijesh.singh@amd.com> References: <20171020023413.122280-21-brijesh.singh@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Brijesh Singh , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Borislav Petkov , Herbert Xu , Gary Hook , Tom Lendacky , linux-crypto@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: Borislav Petkov Return-path: Received: from mail-bn3nam01on0078.outbound.protection.outlook.com ([104.47.33.78]:60384 "EHLO NAM01-BN3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751209AbdJWWUG (ORCPT ); Mon, 23 Oct 2017 18:20:06 -0400 In-Reply-To: <20171020023413.122280-21-brijesh.singh@amd.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: The SEV_PDH_CERT_EXPORT command can be used to export the PDH and its certificate chain. The command is defined in SEV spec section 5.10. Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Borislav Petkov Cc: Herbert Xu Cc: Gary Hook Cc: Tom Lendacky Cc: linux-crypto@vger.kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Brijesh Singh --- Changes since v6: * when sev_do_cmd() and sev_platform_shutdown() fails then propogate the error status code from sev_do_cmd() because it can give us much better reason for the failure. drivers/crypto/ccp/psp-dev.c | 110 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 110 insertions(+) diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index 108fc06bcdb3..b9f594cb10c1 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -390,6 +390,113 @@ static int sev_ioctl_do_pek_cert_import(struct sev_issue_cmd *argp) return ret; } +static int sev_ioctl_do_pdh_cert_export(struct sev_issue_cmd *argp) +{ + struct sev_user_data_pdh_cert_export input; + void *pdh_blob = NULL, *cert_blob = NULL; + struct sev_data_pdh_cert_export *data; + int ret, err; + + if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) + return -EFAULT; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + /* Userspace wants to query the certificate length */ + if (!input.pdh_cert_address || !input.pdh_cert_len || + !input.cert_chain_address || !input.cert_chain_address) + goto cmd; + + /* allocate a physically contiguous buffer to store the PDH blob */ + if (!access_ok(VERIFY_WRITE, input.pdh_cert_address, input.pdh_cert_len) || + (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)) { + ret = -EFAULT; + goto e_free; + } + + pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL); + if (!pdh_blob) { + ret = -ENOMEM; + goto e_free; + } + + data->pdh_cert_address = __psp_pa(pdh_blob); + data->pdh_cert_len = input.pdh_cert_len; + + /* allocate a physically contiguous buffer to store the cert chain blob */ + if (!access_ok(VERIFY_WRITE, input.cert_chain_address, input.cert_chain_len) || + (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)) { + ret = -EFAULT; + goto e_free_pdh; + } + + cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL); + if (!cert_blob) { + ret = -ENOMEM; + goto e_free_pdh; + } + + data->cert_chain_address = __psp_pa(cert_blob); + data->cert_chain_len = input.cert_chain_len; + +cmd: + ret = sev_platform_init(NULL, &argp->error); + if (ret) + goto e_free_cert; + + ret = sev_do_cmd(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error); + + /* + * If we query the length, FW responded with expected data + */ + input.cert_chain_len = data->cert_chain_len; + input.pdh_cert_len = data->pdh_cert_len; + + if (sev_platform_shutdown(&err)) { + /* + * If both sev_do_cmd() and sev_platform_shutdown() commands + * failed then propogate the error code from the sev_do_cmd() + * because it contains a useful status code for the command + * failure. + */ + if (ret) + goto e_free_cert; + + ret = -EIO; + argp->error = err; + goto e_free_cert; + } + + if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { + ret = -EFAULT; + goto e_free_cert; + } + + if (pdh_blob) { + if (copy_to_user((void __user *)input.pdh_cert_address, + pdh_blob, input.pdh_cert_len)) { + ret = -EFAULT; + goto e_free_cert; + } + } + + if (cert_blob) { + if (copy_to_user((void __user *)input.cert_chain_address, + cert_blob, input.cert_chain_len)) + ret = -EFAULT; + } + +e_free_cert: + kfree(cert_blob); +e_free_pdh: + kfree(pdh_blob); +e_free: + kfree(data); + return ret; +} + static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) { void __user *argp = (void __user *)arg; @@ -425,6 +532,9 @@ static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) case SEV_PEK_CERT_IMPORT: ret = sev_ioctl_do_pek_cert_import(&input); break; + case SEV_PDH_CERT_EXPORT: + ret = sev_ioctl_do_pdh_cert_export(&input); + break; default: ret = -EINVAL; goto out; -- 2.9.5