Commit 200664d5 authored by Brijesh Singh's avatar Brijesh Singh
Browse files

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: default avatarBorislav Petkov <bp@suse.de>
Signed-off-by: default avatarBrijesh Singh <brijesh.singh@amd.com>
parent 2a6170df
......@@ -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);
}
......@@ -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 */
......@@ -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
......
......@@ -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 */
......
......@@ -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__ */
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