diff mbox series

[v7,04/18] KVM: SVM: Add support for KVM_SEV_RECEIVE_START command

Message ID c446e7802559c3b274b174769814369ed1d5e912.1588234824.git.ashish.kalra@amd.com (mailing list archive)
State New, archived
Headers show
Series Add AMD SEV guest live migration support | expand

Commit Message

Kalra, Ashish April 30, 2020, 8:42 a.m. UTC
From: Brijesh Singh <Brijesh.Singh@amd.com>

The command is used to create the encryption context for an incoming
SEV guest. The encryption context can be later used by the hypervisor
to import the incoming data into the SEV guest memory space.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
---
 .../virt/kvm/amd-memory-encryption.rst        | 29 +++++++
 arch/x86/kvm/svm/sev.c                        | 81 +++++++++++++++++++
 include/uapi/linux/kvm.h                      |  9 +++
 3 files changed, 119 insertions(+)

Comments

Venu Busireddy May 4, 2020, 9:37 p.m. UTC | #1
On 2020-04-30 08:42:02 +0000, Ashish Kalra wrote:
> From: Brijesh Singh <Brijesh.Singh@amd.com>
> 
> The command is used to create the encryption context for an incoming
> SEV guest. The encryption context can be later used by the hypervisor
> to import the incoming data into the SEV guest memory space.
> 
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: "Radim Krčmář" <rkrcmar@redhat.com>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Borislav Petkov <bp@suse.de>
> Cc: Tom Lendacky <thomas.lendacky@amd.com>
> Cc: x86@kernel.org
> Cc: kvm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Reviewed-by: Steve Rutherford <srutherford@google.com>
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
> ---
>  .../virt/kvm/amd-memory-encryption.rst        | 29 +++++++
>  arch/x86/kvm/svm/sev.c                        | 81 +++++++++++++++++++
>  include/uapi/linux/kvm.h                      |  9 +++
>  3 files changed, 119 insertions(+)
> 
> diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst
> index a45dcb5f8687..ef1f1f3a5b40 100644
> --- a/Documentation/virt/kvm/amd-memory-encryption.rst
> +++ b/Documentation/virt/kvm/amd-memory-encryption.rst
> @@ -322,6 +322,35 @@ issued by the hypervisor to delete the encryption context.
>  
>  Returns: 0 on success, -negative on error
>  
> +13. KVM_SEV_RECEIVE_START
> +------------------------
> +
> +The KVM_SEV_RECEIVE_START command is used for creating the memory encryption
> +context for an incoming SEV guest. To create the encryption context, the user must
> +provide a guest policy, the platform public Diffie-Hellman (PDH) key and session
> +information.
> +
> +Parameters: struct  kvm_sev_receive_start (in/out)
> +
> +Returns: 0 on success, -negative on error
> +
> +::
> +
> +        struct kvm_sev_receive_start {
> +                __u32 handle;           /* if zero then firmware creates a new handle */
> +                __u32 policy;           /* guest's policy */
> +
> +                __u64 pdh_uaddr;         /* userspace address pointing to the PDH key */
> +                __u32 dh_len;
> +
> +                __u64 session_addr;     /* userspace address which points to the guest session information */
> +                __u32 session_len;

Can you address my comments in v6?
(https://lore.kernel.org/kvm/20200402213520.GA658288@vbusired-dt/)

> +        };
> +
> +On success, the 'handle' field contains a new handle and on error, a negative value.
> +
> +For more details, see SEV spec Section 6.12.
> +
>  References
>  ==========
>  
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index 81d661706d31..74a847c9106d 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -1173,6 +1173,84 @@ static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
>  	return ret;
>  }
>  
> +static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
> +{
> +	struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
> +	struct sev_data_receive_start *start;
> +	struct kvm_sev_receive_start params;
> +	int *error = &argp->error;
> +	void *session_data;
> +	void *pdh_data;
> +	int ret;
> +
> +	if (!sev_guest(kvm))
> +		return -ENOTTY;
> +
> +	/* Get parameter from the userspace */
> +	if (copy_from_user(&params, (void __user *)(uintptr_t)argp->data,
> +			sizeof(struct kvm_sev_receive_start)))
> +		return -EFAULT;
> +
> +	/* some sanity checks */
> +	if (!params.pdh_uaddr || !params.pdh_len ||
> +	    !params.session_uaddr || !params.session_len)
> +		return -EINVAL;
> +
> +	pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len);
> +	if (IS_ERR(pdh_data))
> +		return PTR_ERR(pdh_data);
> +
> +	session_data = psp_copy_user_blob(params.session_uaddr,
> +			params.session_len);
> +	if (IS_ERR(session_data)) {
> +		ret = PTR_ERR(session_data);
> +		goto e_free_pdh;
> +	}
> +
> +	ret = -ENOMEM;
> +	start = kzalloc(sizeof(*start), GFP_KERNEL);
> +	if (!start)
> +		goto e_free_session;
> +
> +	start->handle = params.handle;
> +	start->policy = params.policy;
> +	start->pdh_cert_address = __psp_pa(pdh_data);
> +	start->pdh_cert_len = params.pdh_len;
> +	start->session_address = __psp_pa(session_data);
> +	start->session_len = params.session_len;
> +
> +	/* create memory encryption context */
> +	ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, start,
> +				error);
> +	if (ret)
> +		goto e_free;
> +
> +	/* Bind ASID to this guest */
> +	ret = sev_bind_asid(kvm, start->handle, error);
> +	if (ret)
> +		goto e_free;
> +
> +	params.handle = start->handle;
> +	if (copy_to_user((void __user *)(uintptr_t)argp->data,
> +			 &params, sizeof(struct kvm_sev_receive_start))) {
> +		ret = -EFAULT;
> +		sev_unbind_asid(kvm, start->handle);
> +		goto e_free;
> +	}
> +
> +	sev->handle = start->handle;
> +	sev->fd = argp->sev_fd;
> +
> +e_free:
> +	kfree(start);
> +e_free_session:
> +	kfree(session_data);
> +e_free_pdh:
> +	kfree(pdh_data);
> +
> +	return ret;
> +}
> +
>  int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
>  {
>  	struct kvm_sev_cmd sev_cmd;
> @@ -1226,6 +1304,9 @@ int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
>  	case KVM_SEV_SEND_FINISH:
>  		r = sev_send_finish(kvm, &sev_cmd);
>  		break;
> +	case KVM_SEV_RECEIVE_START:
> +		r = sev_receive_start(kvm, &sev_cmd);
> +		break;
>  	default:
>  		r = -EINVAL;
>  		goto out;
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 7aaed8ee33cf..24ac57151d53 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1619,6 +1619,15 @@ struct kvm_sev_send_update_data {
>  	__u32 trans_len;
>  };
>  
> +struct kvm_sev_receive_start {
> +	__u32 handle;
> +	__u32 policy;
> +	__u64 pdh_uaddr;
> +	__u32 pdh_len;
> +	__u64 session_uaddr;
> +	__u32 session_len;
> +};
> +
>  #define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)
>  #define KVM_DEV_ASSIGN_PCI_2_3		(1 << 1)
>  #define KVM_DEV_ASSIGN_MASK_INTX	(1 << 2)
> -- 
> 2.17.1
>
diff mbox series

Patch

diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst
index a45dcb5f8687..ef1f1f3a5b40 100644
--- a/Documentation/virt/kvm/amd-memory-encryption.rst
+++ b/Documentation/virt/kvm/amd-memory-encryption.rst
@@ -322,6 +322,35 @@  issued by the hypervisor to delete the encryption context.
 
 Returns: 0 on success, -negative on error
 
+13. KVM_SEV_RECEIVE_START
+------------------------
+
+The KVM_SEV_RECEIVE_START command is used for creating the memory encryption
+context for an incoming SEV guest. To create the encryption context, the user must
+provide a guest policy, the platform public Diffie-Hellman (PDH) key and session
+information.
+
+Parameters: struct  kvm_sev_receive_start (in/out)
+
+Returns: 0 on success, -negative on error
+
+::
+
+        struct kvm_sev_receive_start {
+                __u32 handle;           /* if zero then firmware creates a new handle */
+                __u32 policy;           /* guest's policy */
+
+                __u64 pdh_uaddr;         /* userspace address pointing to the PDH key */
+                __u32 dh_len;
+
+                __u64 session_addr;     /* userspace address which points to the guest session information */
+                __u32 session_len;
+        };
+
+On success, the 'handle' field contains a new handle and on error, a negative value.
+
+For more details, see SEV spec Section 6.12.
+
 References
 ==========
 
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 81d661706d31..74a847c9106d 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1173,6 +1173,84 @@  static int sev_send_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
 	return ret;
 }
 
+static int sev_receive_start(struct kvm *kvm, struct kvm_sev_cmd *argp)
+{
+	struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
+	struct sev_data_receive_start *start;
+	struct kvm_sev_receive_start params;
+	int *error = &argp->error;
+	void *session_data;
+	void *pdh_data;
+	int ret;
+
+	if (!sev_guest(kvm))
+		return -ENOTTY;
+
+	/* Get parameter from the userspace */
+	if (copy_from_user(&params, (void __user *)(uintptr_t)argp->data,
+			sizeof(struct kvm_sev_receive_start)))
+		return -EFAULT;
+
+	/* some sanity checks */
+	if (!params.pdh_uaddr || !params.pdh_len ||
+	    !params.session_uaddr || !params.session_len)
+		return -EINVAL;
+
+	pdh_data = psp_copy_user_blob(params.pdh_uaddr, params.pdh_len);
+	if (IS_ERR(pdh_data))
+		return PTR_ERR(pdh_data);
+
+	session_data = psp_copy_user_blob(params.session_uaddr,
+			params.session_len);
+	if (IS_ERR(session_data)) {
+		ret = PTR_ERR(session_data);
+		goto e_free_pdh;
+	}
+
+	ret = -ENOMEM;
+	start = kzalloc(sizeof(*start), GFP_KERNEL);
+	if (!start)
+		goto e_free_session;
+
+	start->handle = params.handle;
+	start->policy = params.policy;
+	start->pdh_cert_address = __psp_pa(pdh_data);
+	start->pdh_cert_len = params.pdh_len;
+	start->session_address = __psp_pa(session_data);
+	start->session_len = params.session_len;
+
+	/* create memory encryption context */
+	ret = __sev_issue_cmd(argp->sev_fd, SEV_CMD_RECEIVE_START, start,
+				error);
+	if (ret)
+		goto e_free;
+
+	/* Bind ASID to this guest */
+	ret = sev_bind_asid(kvm, start->handle, error);
+	if (ret)
+		goto e_free;
+
+	params.handle = start->handle;
+	if (copy_to_user((void __user *)(uintptr_t)argp->data,
+			 &params, sizeof(struct kvm_sev_receive_start))) {
+		ret = -EFAULT;
+		sev_unbind_asid(kvm, start->handle);
+		goto e_free;
+	}
+
+	sev->handle = start->handle;
+	sev->fd = argp->sev_fd;
+
+e_free:
+	kfree(start);
+e_free_session:
+	kfree(session_data);
+e_free_pdh:
+	kfree(pdh_data);
+
+	return ret;
+}
+
 int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
 {
 	struct kvm_sev_cmd sev_cmd;
@@ -1226,6 +1304,9 @@  int svm_mem_enc_op(struct kvm *kvm, void __user *argp)
 	case KVM_SEV_SEND_FINISH:
 		r = sev_send_finish(kvm, &sev_cmd);
 		break;
+	case KVM_SEV_RECEIVE_START:
+		r = sev_receive_start(kvm, &sev_cmd);
+		break;
 	default:
 		r = -EINVAL;
 		goto out;
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 7aaed8ee33cf..24ac57151d53 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1619,6 +1619,15 @@  struct kvm_sev_send_update_data {
 	__u32 trans_len;
 };
 
+struct kvm_sev_receive_start {
+	__u32 handle;
+	__u32 policy;
+	__u64 pdh_uaddr;
+	__u32 pdh_len;
+	__u64 session_uaddr;
+	__u32 session_len;
+};
+
 #define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)
 #define KVM_DEV_ASSIGN_PCI_2_3		(1 << 1)
 #define KVM_DEV_ASSIGN_MASK_INTX	(1 << 2)