crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

AMD's new Secure Encrypted Virtualization (SEV) feature allows the
memory contents of virtual machines to be transparently encrypted with a
key unique to the VM. The programming and management of the encryption
keys are handled by the AMD Secure Processor (AMD-SP) which exposes the
commands for these tasks. The complete spec is available at:

http://support.amd.com/TechDocs/55766_SEV-KM%20API_Specification.pdf

Extend the AMD-SP driver to provide the following support:

 - an in-kernel API to communicate with the SEV firmware. The API can be
   used by the hypervisor to create encryption context for a SEV guest.

 - a userspace IOCTL to manage the platform certificates.

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
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>

1 files changed, 137 insertions, 0 deletions

diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h
index 4a150d17d537..0b6dd306d88b 100644
--- a/include/linux/psp-sev.h
+++ b/include/linux/psp-sev.h
@@ -462,4 +462,141 @@ struct sev_data_dbg {
 	u32 len;				/* In */
 } __packed;
 
+#ifdef CONFIG_CRYPTO_DEV_SP_PSP
+
+/**
+ * sev_platform_init - perform SEV INIT command
+ *
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ */
+int sev_platform_init(int *error);
+
+/**
+ * sev_platform_status - perform SEV PLATFORM_STATUS command
+ *
+ * @status: sev_user_data_status structure to be processed
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ */
+int sev_platform_status(struct sev_user_data_status *status, int *error);
+
+/**
+ * sev_issue_cmd_external_user - issue SEV command by other driver with a file
+ * handle.
+ *
+ * This function can be used by other drivers to issue a SEV command on
+ * behalf of userspace. The caller must pass a valid SEV file descriptor
+ * so that we know that it has access to SEV device.
+ *
+ * @filep - SEV device file pointer
+ * @cmd - command to issue
+ * @data - command buffer
+ * @error: SEV command return code
+ *
+ * Returns:
+ * 0 if the SEV successfully processed the command
+ * -%ENODEV    if the SEV device is not available
+ * -%ENOTSUPP  if the SEV does not support SEV
+ * -%ETIMEDOUT if the SEV command timed out
+ * -%EIO       if the SEV returned a non-zero return code
+ * -%EINVAL    if the SEV file descriptor is not valid
+ */
+int sev_issue_cmd_external_user(struct file *filep, unsigned int id,
+				void *data, int *error);
+
+/**
+ * sev_guest_deactivate - perform SEV DEACTIVATE command
+ *
+ * @deactivate: sev_data_deactivate structure to be processed
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_deactivate(struct sev_data_deactivate *data, int *error);
+
+/**
+ * sev_guest_activate - perform SEV ACTIVATE command
+ *
+ * @activate: sev_data_activate structure to be processed
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_activate(struct sev_data_activate *data, int *error);
+
+/**
+ * sev_guest_df_flush - perform SEV DF_FLUSH command
+ *
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_df_flush(int *error);
+
+/**
+ * sev_guest_decommission - perform SEV DECOMMISSION command
+ *
+ * @decommission: sev_data_decommission structure to be processed
+ * @sev_ret: sev command return code
+ *
+ * Returns:
+ * 0 if the sev successfully processed the command
+ * -%ENODEV    if the sev device is not available
+ * -%ENOTSUPP  if the sev does not support SEV
+ * -%ETIMEDOUT if the sev command timed out
+ * -%EIO       if the sev returned a non-zero return code
+ */
+int sev_guest_decommission(struct sev_data_decommission *data, int *error);
+
+#else	/* !CONFIG_CRYPTO_DEV_SP_PSP */
+
+static inline int
+sev_platform_status(struct sev_user_data_status *status, int *error) { return -ENODEV; }
+
+static inline int sev_platform_init(int *error) { return -ENODEV; }
+
+static inline int
+sev_guest_deactivate(struct sev_data_deactivate *data, int *error) { return -ENODEV; }
+
+static inline int
+sev_guest_decommission(struct sev_data_decommission *data, int *error) { return -ENODEV; }
+
+static inline int
+sev_guest_activate(struct sev_data_activate *data, int *error) { return -ENODEV; }
+
+static inline int sev_guest_df_flush(int *error) { return -ENODEV; }
+
+static inline int
+sev_issue_cmd_external_user(struct file *filep, unsigned int id, void *data, int *error) { return -ENODEV; }
+
+#endif	/* CONFIG_CRYPTO_DEV_SP_PSP */
+
 #endif	/* __PSP_SEV_H__ */