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

From: Gary R Hook
Date: Tue Oct 24 2017 - 14:44:40 EST


On 10/23/2017 04:55 PM, Brijesh Singh wrote:
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@xxxxxxxxxx>
Cc: "Radim KrÄmÃÅ" <rkrcmar@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: Gary Hook <gary.hook@xxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: kvm@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>

Acked-by: Gary R Hook <gary.hook@xxxxxxx>

---

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;