by Gary R Hook

[permalink] [raw]

Subject: Re: [Part2 PATCH v8 13/38] crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support

On 11/06/2017 12:11 PM, Brijesh Singh wrote:
> 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 <[email protected]>
> Cc: "Radim Krčmář" <[email protected]>
> Cc: Borislav Petkov <[email protected]>
> Cc: Herbert Xu <[email protected]>
> Cc: Gary Hook <[email protected]>
> Cc: Tom Lendacky <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Improvements-by: Borislav Petkov <[email protected]>
> Signed-off-by: Brijesh Singh <[email protected]>

Acked-by: Gary R Hook <[email protected]>

> ---
> drivers/crypto/ccp/psp-dev.c | 344 +++++++++++++++++++++++++++++++++++++++++++
> drivers/crypto/ccp/psp-dev.h | 24 +++
> drivers/crypto/ccp/sp-dev.c | 9 ++
> drivers/crypto/ccp/sp-dev.h | 4 +
> include/linux/psp-sev.h | 137 +++++++++++++++++
> 5 files changed, 518 insertions(+)
>
> diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
> index b5789f878560..9915a6c604a3 100644
> --- a/drivers/crypto/ccp/psp-dev.c
> +++ b/drivers/crypto/ccp/psp-dev.c
> @@ -26,6 +26,12 @@
> #include "sp-dev.h"
> #include "psp-dev.h"
>
> +#define DEVICE_NAME "sev"
> +
> +static DEFINE_MUTEX(sev_cmd_mutex);
> +static struct sev_misc_dev *misc_dev;
> +static struct psp_device *psp_master;
> +
> static struct psp_device *psp_alloc_struct(struct sp_device *sp)
> {
> struct device *dev = sp->dev;
> @@ -45,9 +51,285 @@ static struct psp_device *psp_alloc_struct(struct sp_device *sp)
>
> static irqreturn_t psp_irq_handler(int irq, void *data)
> {
> + struct psp_device *psp = data;
> + unsigned int status;
> + int reg;
> +
> + /* Read the interrupt status: */
> + status = ioread32(psp->io_regs + PSP_P2CMSG_INTSTS);
> +
> + /* Check if it is command completion: */
> + if (!(status & BIT(PSP_CMD_COMPLETE_REG)))
> + goto done;
> +
> + /* Check if it is SEV command completion: */
> + reg = ioread32(psp->io_regs + PSP_CMDRESP);
> + if (reg & PSP_CMDRESP_RESP) {
> + psp->sev_int_rcvd = 1;
> + wake_up(&psp->sev_int_queue);
> + }
> +
> +done:
> + /* Clear the interrupt status by writing the same value we read. */
> + iowrite32(status, psp->io_regs + PSP_P2CMSG_INTSTS);
> +
> return IRQ_HANDLED;
> }
>
> +static void sev_wait_cmd_ioc(struct psp_device *psp, unsigned int *reg)
> +{
> + psp->sev_int_rcvd = 0;
> +
> + wait_event(psp->sev_int_queue, psp->sev_int_rcvd);
> + *reg = ioread32(psp->io_regs + PSP_CMDRESP);
> +}
> +
> +static int sev_cmd_buffer_len(int cmd)
> +{
> + switch (cmd) {
> + case SEV_CMD_INIT: return sizeof(struct sev_data_init);
> + case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status);
> + case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr);
> + case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import);
> + case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export);
> + case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start);
> + case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data);
> + case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa);
> + case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish);
> + case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure);
> + case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate);
> + case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate);
> + case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission);
> + case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status);
> + case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg);
> + case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg);
> + case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start);
> + case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data);
> + case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa);
> + case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish);
> + case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start);
> + case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish);
> + case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data);
> + case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa);
> + case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret);
> + default: return 0;
> + }
> +
> + return 0;
> +}
> +
> +static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
> +{
> + struct psp_device *psp = psp_master;
> + unsigned int phys_lsb, phys_msb;
> + unsigned int reg, ret = 0;
> +
> + if (!psp)
> + return -ENODEV;
> +
> + /* Get the physical address of the command buffer */
> + phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
> + phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
> +
> + dev_dbg(psp->dev, "sev command id %#x buffer 0x%08x%08x\n",
> + cmd, phys_msb, phys_lsb);
> +
> + print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data,
> + sev_cmd_buffer_len(cmd), false);
> +
> + iowrite32(phys_lsb, psp->io_regs + PSP_CMDBUFF_ADDR_LO);
> + iowrite32(phys_msb, psp->io_regs + PSP_CMDBUFF_ADDR_HI);
> +
> + reg = cmd;
> + reg <<= PSP_CMDRESP_CMD_SHIFT;
> + reg |= PSP_CMDRESP_IOC;
> + iowrite32(reg, psp->io_regs + PSP_CMDRESP);
> +
> + /* wait for command completion */
> + sev_wait_cmd_ioc(psp, &reg);
> +
> + if (psp_ret)
> + *psp_ret = reg & PSP_CMDRESP_ERR_MASK;
> +
> + if (reg & PSP_CMDRESP_ERR_MASK) {
> + dev_dbg(psp->dev, "sev command %#x failed (%#010x)\n",
> + cmd, reg & PSP_CMDRESP_ERR_MASK);
> + ret = -EIO;
> + }
> +
> + print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
> + sev_cmd_buffer_len(cmd), false);
> +
> + return ret;
> +}
> +
> +static int sev_do_cmd(int cmd, void *data, int *psp_ret)
> +{
> + int rc;
> +
> + mutex_lock(&sev_cmd_mutex);
> + rc = __sev_do_cmd_locked(cmd, data, psp_ret);
> + mutex_unlock(&sev_cmd_mutex);
> +
> + return rc;
> +}
> +
> +static int __sev_platform_init_locked(int *error)
> +{
> + struct psp_device *psp = psp_master;
> + int rc = 0;
> +
> + if (!psp)
> + return -ENODEV;
> +
> + if (psp->sev_state == SEV_STATE_INIT)
> + return 0;
> +
> + rc = __sev_do_cmd_locked(SEV_CMD_INIT, &psp->init_cmd_buf, error);
> + if (rc)
> + return rc;
> +
> + psp->sev_state = SEV_STATE_INIT;
> + dev_dbg(psp->dev, "SEV firmware initialized\n");
> +
> + return rc;
> +}
> +
> +int sev_platform_init(int *error)
> +{
> + int rc;
> +
> + mutex_lock(&sev_cmd_mutex);
> + rc = __sev_platform_init_locked(error);
> + mutex_unlock(&sev_cmd_mutex);
> +
> + return rc;
> +}
> +EXPORT_SYMBOL_GPL(sev_platform_init);
> +
> +static int __sev_platform_shutdown_locked(int *error)
> +{
> + int ret;
> +
> + ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, 0, error);
> + if (ret)
> + return ret;
> +
> + psp_master->sev_state = SEV_STATE_UNINIT;
> + dev_dbg(psp_master->dev, "SEV firmware shutdown\n");
> +
> + return ret;
> +}
> +
> +static int sev_platform_shutdown(int *error)
> +{
> + int rc;
> +
> + mutex_lock(&sev_cmd_mutex);
> + rc = __sev_platform_shutdown_locked(NULL);
> + mutex_unlock(&sev_cmd_mutex);
> +
> + return rc;
> +}
> +
> +static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
> +{
> + return -ENOTTY;
> +}
> +
> +static const struct file_operations sev_fops = {
> + .owner = THIS_MODULE,
> + .unlocked_ioctl = sev_ioctl,
> +};
> +
> +int sev_platform_status(struct sev_user_data_status *data, int *error)
> +{
> + return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
> +}
> +EXPORT_SYMBOL_GPL(sev_platform_status);
> +
> +int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
> +{
> + return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
> +}
> +EXPORT_SYMBOL_GPL(sev_guest_deactivate);
> +
> +int sev_guest_activate(struct sev_data_activate *data, int *error)
> +{
> + return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
> +}
> +EXPORT_SYMBOL_GPL(sev_guest_activate);
> +
> +int sev_guest_decommission(struct sev_data_decommission *data, int *error)
> +{
> + return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
> +}
> +EXPORT_SYMBOL_GPL(sev_guest_decommission);
> +
> +int sev_guest_df_flush(int *error)
> +{
> + return sev_do_cmd(SEV_CMD_DF_FLUSH, 0, error);
> +}
> +EXPORT_SYMBOL_GPL(sev_guest_df_flush);
> +
> +static void sev_exit(struct kref *ref)
> +{
> + struct sev_misc_dev *misc_dev = container_of(ref, struct sev_misc_dev, refcount);
> +
> + misc_deregister(&misc_dev->misc);
> +}
> +
> +static int sev_misc_init(struct psp_device *psp)
> +{
> + struct device *dev = psp->dev;
> + int ret;
> +
> + /*
> + * SEV feature support can be detected on multiple devices but the SEV
> + * FW commands must be issued on the master. During probe, we do not
> + * know the master hence we create /dev/sev on the first device probe.
> + * sev_do_cmd() finds the right master device to which to issue the
> + * command to the firmware.
> + */
> + if (!misc_dev) {
> + struct miscdevice *misc;
> +
> + misc_dev = devm_kzalloc(dev, sizeof(*misc_dev), GFP_KERNEL);
> + if (!misc_dev)
> + return -ENOMEM;
> +
> + misc = &misc_dev->misc;
> + misc->minor = MISC_DYNAMIC_MINOR;
> + misc->name = DEVICE_NAME;
> + misc->fops = &sev_fops;
> +
> + ret = misc_register(misc);
> + if (ret)
> + return ret;
> +
> + kref_init(&misc_dev->refcount);
> + } else {
> + kref_get(&misc_dev->refcount);
> + }
> +
> + init_waitqueue_head(&psp->sev_int_queue);
> + psp->sev_misc = misc_dev;
> + dev_dbg(dev, "registered SEV device\n");
> +
> + return 0;
> +}
> +
> +static int sev_init(struct psp_device *psp)
> +{
> + /* Check if device supports SEV feature */
> + if (!(ioread32(psp->io_regs + PSP_FEATURE_REG) & 1)) {
> + dev_dbg(psp->dev, "device does not support SEV\n");
> + return 1;
> + }
> +
> + return sev_misc_init(psp);
> +}
> +
> int psp_dev_init(struct sp_device *sp)
> {
> struct device *dev = sp->dev;
> @@ -81,6 +363,10 @@ int psp_dev_init(struct sp_device *sp)
> goto e_err;
> }
>
> + ret = sev_init(psp);
> + if (ret)
> + goto e_irq;
> +
> if (sp->set_psp_master_device)
> sp->set_psp_master_device(sp);
>
> @@ -89,6 +375,8 @@ int psp_dev_init(struct sp_device *sp)
>
> return 0;
>
> +e_irq:
> + sp_free_psp_irq(psp->sp, psp);
> e_err:
> sp->psp_data = NULL;
>
> @@ -101,5 +389,61 @@ void psp_dev_destroy(struct sp_device *sp)
> {
> struct psp_device *psp = sp->psp_data;
>
> + if (psp->sev_misc)
> + kref_put(&misc_dev->refcount, sev_exit);
> +
> sp_free_psp_irq(sp, psp);
> }
> +
> +int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
> + void *data, int *error)
> +{
> + if (!filep || filep->f_op != &sev_fops)
> + return -EBADF;
> +
> + return sev_do_cmd(cmd, data, error);
> +}
> +EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
> +
> +void psp_pci_init(void)
> +{
> + struct sev_user_data_status *status;
> + struct sp_device *sp;
> + int error, rc;
> +
> + sp = sp_get_psp_master_device();
> + if (!sp)
> + return;
> +
> + psp_master = sp->psp_data;
> +
> + /* Initialize the platform */
> + rc = sev_platform_init(&error);
> + if (rc) {
> + dev_err(sp->dev, "SEV: failed to INIT error %#x\n", error);
> + goto err;
> + }
> +
> + /* Display SEV firmware version */
> + status = &psp_master->status_cmd_buf;
> + rc = sev_platform_status(status, &error);
> + if (rc) {
> + dev_err(sp->dev, "SEV: failed to get status error %#x\n", error);
> + goto err;
> + }
> +
> + dev_info(sp->dev, "SEV API:%d.%d build:%d\n", status->api_major,
> + status->api_minor, status->build);
> + return;
> +
> +err:
> + psp_master = NULL;
> +}
> +
> +void psp_pci_exit(void)
> +{
> + if (!psp_master)
> + return;
> +
> + sev_platform_shutdown(NULL);
> +}
> diff --git a/drivers/crypto/ccp/psp-dev.h b/drivers/crypto/ccp/psp-dev.h
> index 55b7808367c3..c81f0b11287a 100644
> --- a/drivers/crypto/ccp/psp-dev.h
> +++ b/drivers/crypto/ccp/psp-dev.h
> @@ -25,9 +25,21 @@
> #include <linux/interrupt.h>
> #include <linux/irqreturn.h>
> #include <linux/dmaengine.h>
> +#include <linux/psp-sev.h>
> +#include <linux/miscdevice.h>
>
> #include "sp-dev.h"
>
> +#define PSP_C2PMSG(_num) ((_num) << 2)
> +#define PSP_CMDRESP PSP_C2PMSG(32)
> +#define PSP_CMDBUFF_ADDR_LO PSP_C2PMSG(56)
> +#define PSP_CMDBUFF_ADDR_HI PSP_C2PMSG(57)
> +#define PSP_FEATURE_REG PSP_C2PMSG(63)
> +
> +#define PSP_P2CMSG(_num) ((_num) << 2)
> +#define PSP_CMD_COMPLETE_REG 1
> +#define PSP_CMD_COMPLETE PSP_P2CMSG(PSP_CMD_COMPLETE_REG)
> +
> #define PSP_P2CMSG_INTEN 0x0110
> #define PSP_P2CMSG_INTSTS 0x0114
>
> @@ -44,6 +56,11 @@
>
> #define MAX_PSP_NAME_LEN 16
>
> +struct sev_misc_dev {
> + struct kref refcount;
> + struct miscdevice misc;
> +};
> +
> struct psp_device {
> struct list_head entry;
>
> @@ -54,6 +71,13 @@ struct psp_device {
> struct sp_device *sp;
>
> void __iomem *io_regs;
> +
> + int sev_state;
> + unsigned int sev_int_rcvd;
> + wait_queue_head_t sev_int_queue;
> + struct sev_misc_dev *sev_misc;
> + struct sev_user_data_status status_cmd_buf;
> + struct sev_data_init init_cmd_buf;
> };
>
> #endif /* __PSP_DEV_H */
> diff --git a/drivers/crypto/ccp/sp-dev.c b/drivers/crypto/ccp/sp-dev.c
> index cf101c039c8f..eb0da6572720 100644
> --- a/drivers/crypto/ccp/sp-dev.c
> +++ b/drivers/crypto/ccp/sp-dev.c
> @@ -272,6 +272,10 @@ static int __init sp_mod_init(void)
> if (ret)
> return ret;
>
> +#ifdef CONFIG_CRYPTO_DEV_SP_PSP
> + psp_pci_init();
> +#endif
> +
> return 0;
> #endif
>
> @@ -291,6 +295,11 @@ static int __init sp_mod_init(void)
> static void __exit sp_mod_exit(void)
> {
> #ifdef CONFIG_X86
> +
> +#ifdef CONFIG_CRYPTO_DEV_SP_PSP
> + psp_pci_exit();
> +#endif
> +
> sp_pci_exit();
> #endif
>
> diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h
> index 909cf3e436b4..acb197b66ced 100644
> --- a/drivers/crypto/ccp/sp-dev.h
> +++ b/drivers/crypto/ccp/sp-dev.h
> @@ -143,12 +143,16 @@ static inline int ccp_dev_resume(struct sp_device *sp)
> #ifdef CONFIG_CRYPTO_DEV_SP_PSP
>
> int psp_dev_init(struct sp_device *sp);
> +void psp_pci_init(void);
> void psp_dev_destroy(struct sp_device *sp);
> +void psp_pci_exit(void);
>
> #else /* !CONFIG_CRYPTO_DEV_SP_PSP */
>
> static inline int psp_dev_init(struct sp_device *sp) { return 0; }
> +static inline void psp_pci_init(void) { }
> static inline void psp_dev_destroy(struct sp_device *sp) { }
> +static inline void psp_pci_exit(void) { }
>
> #endif /* CONFIG_CRYPTO_DEV_SP_PSP */
>
> 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__ */
>

2017-11-07 15:47:42

by Gary R Hook

[permalink] [raw]

Subject: Re: [Part2 PATCH v8 14/38] crypto: ccp: Implement SEV_FACTORY_RESET ioctl command

On 11/06/2017 12:11 PM, Brijesh Singh wrote:
> The SEV_FACTORY_RESET command can be used by the platform owner to
> reset the non-volatile SEV related data. The command is defined in
> SEV spec section 5.4
>
> Cc: Paolo Bonzini <[email protected]>
> Cc: "Radim Krčmář" <[email protected]>
> Cc: Borislav Petkov <[email protected]>
> Cc: Herbert Xu <[email protected]>
> Cc: Gary Hook <[email protected]>
> Cc: Tom Lendacky <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Improvements-by: Borislav Petkov <[email protected]>
> Signed-off-by: Brijesh Singh <[email protected]>

Acked-by: Gary R Hook <[email protected]>

> ---
> drivers/crypto/ccp/psp-dev.c | 77 +++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 76 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
> index 9915a6c604a3..b49583a45a55 100644
> --- a/drivers/crypto/ccp/psp-dev.c
> +++ b/drivers/crypto/ccp/psp-dev.c
> @@ -232,9 +232,84 @@ static int sev_platform_shutdown(int *error)
> return rc;
> }
>
> +static int sev_get_platform_state(int *state, int *error)
> +{
> + int rc;
> +
> + rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
> + &psp_master->status_cmd_buf, error);
> + if (rc)
> + return rc;
> +
> + *state = psp_master->status_cmd_buf.state;
> + return rc;
> +}
> +
> +static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
> +{
> + int state, rc;
> +
> + /*
> + * The SEV spec requires that FACTORY_RESET must be issued in
> + * UNINIT state. Before we go further lets check if any guest is
> + * active.
> + *
> + * If FW is in WORKING state then deny the request otherwise issue
> + * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
> + *
> + */
> + rc = sev_get_platform_state(&state, &argp->error);
> + if (rc)
> + return rc;
> +
> + if (state == SEV_STATE_WORKING)
> + return -EBUSY;
> +
> + if (state == SEV_STATE_INIT) {
> + rc = __sev_platform_shutdown_locked(&argp->error);
> + if (rc)
> + return rc;
> + }
> +
> + return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, &argp->error);
> +}
> +
> static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
> {
> - return -ENOTTY;
> + void __user *argp = (void __user *)arg;
> + struct sev_issue_cmd input;
> + int ret = -EFAULT;
> +
> + if (!psp_master)
> + return -ENODEV;
> +
> + if (ioctl != SEV_ISSUE_CMD)
> + return -EINVAL;
> +
> + if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
> + return -EFAULT;
> +
> + if (input.cmd > SEV_MAX)
> + return -EINVAL;
> +
> + mutex_lock(&sev_cmd_mutex);
> +
> + switch (input.cmd) {
> +
> + case SEV_FACTORY_RESET:
> + ret = sev_ioctl_do_reset(&input);
> + break;
> + default:
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
> + ret = -EFAULT;
> +out:
> + mutex_unlock(&sev_cmd_mutex);
> +
> + return ret;
> }
>
> static const struct file_operations sev_fops = {
>