[Part2 PATCH v6.1 16/38] crypto: ccp: Implement SEV_PEK_GEN ioctl command

[Brijesh Singh <brijesh.singh@amd.com>]

The SEV_PEK_GEN command is used to generate a new Platform Endorsement
Key (PEK). The command is defined in SEV spec section 5.6.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-crypto@vger.kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---

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 | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index dd4bab143de9..18e2d8291997 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -195,6 +195,34 @@ static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
 	return ret;
 }
 
+static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp)
+{
+	int ret, err;
+
+	ret = sev_platform_init(NULL, &argp->error);
+	if (ret)
+		return ret;
+
+	ret = sev_do_cmd(cmd, 0, &argp->error);
+
+	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 done;
+
+		argp->error = err;
+		ret = -EIO;
+	}
+
+done:
+	return ret;
+}
+
 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
 {
 	void __user *argp = (void __user *)arg;
@@ -218,6 +246,9 @@ static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
 	case SEV_PLATFORM_STATUS:
 		ret = sev_ioctl_do_platform_status(&input);
 		break;
+	case SEV_PEK_GEN:
+		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input);
+		break;
 	default:
 		ret = -EINVAL;
 		goto out;
-- 
2.9.5