[Part2 PATCH v6 24/38] KVM: Define SEV key management command id

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

Define Secure Encrypted Virtualization (SEV) key management command id
and structure. The command definition is available in SEV KM [1] spec
0.14 (http://support.amd.com/TechDocs/55766_SEV-KM API_Specification.pdf)
and Documentation/virtual/kvm/amd-memory-encryption.txt.

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
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 .../virtual/kvm/amd-memory-encryption.txt          | 163 +++++++++++++++++++++
 include/uapi/linux/kvm.h                           |  80 ++++++++++
 2 files changed, 243 insertions(+)

diff --git a/Documentation/virtual/kvm/amd-memory-encryption.txt b/Documentation/virtual/kvm/amd-memory-encryption.txt
index 26472b4cdbaf..1ec5517f2948 100644
--- a/Documentation/virtual/kvm/amd-memory-encryption.txt
+++ b/Documentation/virtual/kvm/amd-memory-encryption.txt
@@ -36,3 +36,166 @@ setting the SEV bit before executing VMRUN.
 SEV hardware uses ASIDs to associate a memory encryption key with a VM.
 Hence, the ASID for the SEV-enabled guests must be from 1 to a maximum value
 defined in the CPUID 0x8000001f[ecx] field.
+
+SEV Key Management
+------------------
+
+The SEV guest key management is handled by a separate processor called the AMD
+Secure Processor (AMD-SP). Firmware running inside the AMD-SP provides a secure
+key management interface to perform common hypervisor activities such as
+encrypting bootstrap code, snapshot, migrating and debugging the guest. For more
+information, see the SEV Key Management spec:
+http://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf
+
+KVM implements the following commands to support common lifecycle events of SEV
+guests, such as launching, running, snapshotting, migrating and decommissioning.
+
+1. KVM_SEV_INIT
+
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_INIT command is used by the hypervisor to initialize the SEV platform
+context. In a typical workflow, this command should be the first command issued.
+
+2. KVM_SEV_LAUNCH_START
+
+Parameters: struct  kvm_sev_launch_start (in/out)
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_LAUNCH_START command is used for creating the memory encryption
+context. To create the encryption context, user must provide a guest policy,
+the owner's public Diffie-Hellman (PDH) key and session information.
+
+struct kvm_sev_launch_start {
+	__u32 handle;		/* if zero then firmware creates a new handle */
+	__u32 policy;		/* guest's policy */
+
+	__u64 dh_uaddr;		/* userspace address pointing to the guest owner's 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 6.2.
+
+3. KVM_SEV_LAUNCH_UPDATE_DATA
+
+Parameters (in): struct  kvm_sev_launch_update_data
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_LAUNCH_UPDATE_DATA is used for encrypting a memory region. It also
+calculates a measurement of the memory contents. The measurement is a signature
+of the memory contents that can be sent to the guest owner as an attestation
+that the memory was encrypted correctly by the firmware.
+
+struct kvm_sev_launch_update {
+	__u64 uaddr;		/* userspace address to be encrypted (must be 16-byte aligned) */
+	__u32 len;		/* length of the data to be encrypted (must be 16-byte aligned) */
+};
+
+For more details, see SEV spec Section 6.3.
+
+4. KVM_SEV_LAUNCH_MEASURE
+
+Parameters (in): struct  kvm_sev_launch_measure
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_LAUNCH_MEASURE command is used to retrieve the measurement of the
+data encrypted by the KVM_SEV_LAUNCH_UPDATE_DATA command. The guest owner may
+wait to provide the guest with confidential information until it can verify the
+measurement. Since the guest owner knows the initial contents of the guest at
+boot, the measurement can be verified by comparing it to what the guest owner
+expects.
+
+struct kvm_sev_launch_measure {
+	__u64 uaddr;		/* where to copy the measurement */
+	__u32 len;		/* length of measurement blob */
+};
+
+For more details on the measurement verification flow, see SEV spec Section 6.4.
+
+5. KVM_SEV_LAUNCH_FINISH
+
+Returns: 0 on success, -negative on error
+
+After completion of the launch flow, the KVM_SEV_LAUNCH_FINISH command can be
+issued to make the guest ready for the execution.
+
+6. KVM_SEV_GUEST_STATUS
+
+Parameters (out): struct kvm_sev_guest_status
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_GUEST_STATUS command is used to retrieve status information about a
+SEV-enabled guest.
+
+struct kvm_sev_guest_status {
+	__u32 handle;		/* guest handle */
+	__u32 policy;		/* guest policy */
+	__u8 state;		/* guest state (see enum below) */
+};
+
+SEV guest state:
+
+enum {
+	SEV_STATE_INVALID = 0;
+	SEV_STATE_LAUNCHING,	/* guest is currently being launched */
+	SEV_STATE_SECRET,	/* guest is being launched and ready to accept the ciphertext data */
+	SEV_STATE_RUNNING,	/* guest is fully launched and running */
+	SEV_STATE_RECEIVING,	/* guest is being migrated in from another SEV machine */
+	SEV_STATE_SENDING	/* guest is getting migrated out to another SEV machine */
+};
+
+7. KVM_SEV_DBG_DECRYPT
+
+Parameters (in): struct kvm_sev_dbg
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_DEBUG_DECRYPT command can be used by the hypervisor to request the
+firmware to decrypt the data at the given memory region.
+
+struct kvm_sev_dbg {
+	__u64 src_uaddr;	/* userspace address of data to decrypt */
+	__u64 dst_uaddr;	/* userspace address of destination */
+	__u32 len;		/* length of memory region to decrypt */
+};
+
+The command returns an error if the guest policy does not allow debugging.
+
+8. KVM_SEV_DBG_ENCRYPT
+
+Parameters (in): struct kvm_sev_dbg
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_DEBUG_ENCRYPT command can be used by the hypervisor to request the
+firmware to encrypt the data at the given memory region.
+
+struct kvm_sev_dbg {
+	__u64 src_uaddr;	/* userspace address of data to encrypt */
+	__u64 dst_uaddr;	/* userspace address of destination */
+	__u32 len;		/* length of memory region to encrypt */
+};
+
+The command returns an error if the guest policy does not allow debugging.
+
+9. KVM_SEV_LAUNCH_SECRET
+
+Parameters (in): struct kvm_sev_launch_secret
+Returns: 0 on success, -negative on error
+
+The KVM_SEV_LAUNCH_SECRET command can be used by the hypervisor to inject secret
+data after the measurement has been validated by the guest owner.
+
+struct kvm_sev_launch_secret {
+	__u64 hdr_uaddr;	/* userspace address containing the packet header */
+	__u32 hdr_len;
+
+	__u64 guest_uaddr;	/* the guest memory region where the secret should be injected */
+	__u32 guest_len;
+
+	__u64 trans_uaddr;	/* the hypervisor memory region which contains the secret */
+	__u32 trans_len;
+};
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 1f9f26a8e111..027153971c97 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1367,6 +1367,86 @@ struct kvm_enc_region {
 #define KVM_MEMORY_ENCRYPT_REG_REGION    _IOR(KVMIO, 0xbb, struct kvm_enc_region)
 #define KVM_MEMORY_ENCRYPT_UNREG_REGION  _IOR(KVMIO, 0xbc, struct kvm_enc_region)
 
+/* Secure Encrypted Virtualization command */
+enum sev_cmd_id {
+	/* Guest initialization commands */
+	KVM_SEV_INIT = 0,
+	KVM_SEV_ES_INIT,
+	/* Guest launch commands */
+	KVM_SEV_LAUNCH_START,
+	KVM_SEV_LAUNCH_UPDATE_DATA,
+	KVM_SEV_LAUNCH_UPDATE_VMSA,
+	KVM_SEV_LAUNCH_SECRET,
+	KVM_SEV_LAUNCH_MEASURE,
+	KVM_SEV_LAUNCH_FINISH,
+	/* Guest migration commands (outgoing) */
+	KVM_SEV_SEND_START,
+	KVM_SEV_SEND_UPDATE_DATA,
+	KVM_SEV_SEND_UPDATE_VMSA,
+	KVM_SEV_SEND_FINISH,
+	/* Guest migration commands (incoming) */
+	KVM_SEV_RECEIVE_START,
+	KVM_SEV_RECEIVE_UPDATE_DATA,
+	KVM_SEV_RECEIVE_UPDATE_VMSA,
+	KVM_SEV_RECEIVE_FINISH,
+	/* Guest status and debug commands */
+	KVM_SEV_GUEST_STATUS,
+	KVM_SEV_DBG_DECRYPT,
+	KVM_SEV_DBG_ENCRYPT,
+	/* Guest certificates commands */
+	KVM_SEV_CERT_EXPORT,
+
+	KVM_SEV_NR_MAX,
+};
+
+struct kvm_sev_cmd {
+	__u32 id;
+	__u64 data;
+	__u32 error;
+	__u32 sev_fd;
+};
+
+struct kvm_sev_launch_start {
+	__u32 handle;
+	__u32 policy;
+	__u64 dh_uaddr;
+	__u32 dh_len;
+	__u64 session_uaddr;
+	__u32 session_len;
+};
+
+struct kvm_sev_launch_update_data {
+	__u64 uaddr;
+	__u32 len;
+};
+
+
+struct kvm_sev_launch_secret {
+	__u64 hdr_uaddr;
+	__u32 hdr_len;
+	__u64 guest_uaddr;
+	__u32 guest_len;
+	__u64 trans_uaddr;
+	__u32 trans_len;
+};
+
+struct kvm_sev_launch_measure {
+	__u64 uaddr;
+	__u32 len;
+};
+
+struct kvm_sev_guest_status {
+	__u32 handle;
+	__u32 policy;
+	__u32 state;
+};
+
+struct kvm_sev_dbg {
+	__u64 src_uaddr;
+	__u64 dst_uaddr;
+	__u32 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)
-- 
2.9.5