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authorLinus Torvalds <torvalds@linux-foundation.org>2022-12-12 14:27:49 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2022-12-12 14:27:49 -0800
commita89ef2aa552db985e0ee8cb458846298c007704c (patch)
tree7b12bb9f92f91b52da1a674b2ebb2aa8aa3382ae /drivers
parent2da68a77b940722b04c2f7604a758eab46cf6cf9 (diff)
parent00e07cfbdf0b232f7553f0175f8f4e8d792f7e90 (diff)
Merge tag 'x86_tdx_for_6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 tdx updates from Dave Hansen: "This includes a single chunk of new functionality for TDX guests which allows them to talk to the trusted TDX module software and obtain an attestation report. This report can then be used to prove the trustworthiness of the guest to a third party and get access to things like storage encryption keys" * tag 'x86_tdx_for_6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: selftests/tdx: Test TDX attestation GetReport support virt: Add TDX guest driver x86/tdx: Add a wrapper to get TDREPORT0 from the TDX Module
Diffstat (limited to 'drivers')
-rw-r--r--drivers/virt/Kconfig2
-rw-r--r--drivers/virt/Makefile1
-rw-r--r--drivers/virt/coco/tdx-guest/Kconfig10
-rw-r--r--drivers/virt/coco/tdx-guest/Makefile2
-rw-r--r--drivers/virt/coco/tdx-guest/tdx-guest.c102
5 files changed, 117 insertions, 0 deletions
diff --git a/drivers/virt/Kconfig b/drivers/virt/Kconfig
index 87ef258cec64..f79ab13a5c28 100644
--- a/drivers/virt/Kconfig
+++ b/drivers/virt/Kconfig
@@ -52,4 +52,6 @@ source "drivers/virt/coco/efi_secret/Kconfig"
source "drivers/virt/coco/sev-guest/Kconfig"
+source "drivers/virt/coco/tdx-guest/Kconfig"
+
endif
diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile
index 093674e05c40..e9aa6fc96fab 100644
--- a/drivers/virt/Makefile
+++ b/drivers/virt/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_NITRO_ENCLAVES) += nitro_enclaves/
obj-$(CONFIG_ACRN_HSM) += acrn/
obj-$(CONFIG_EFI_SECRET) += coco/efi_secret/
obj-$(CONFIG_SEV_GUEST) += coco/sev-guest/
+obj-$(CONFIG_INTEL_TDX_GUEST) += coco/tdx-guest/
diff --git a/drivers/virt/coco/tdx-guest/Kconfig b/drivers/virt/coco/tdx-guest/Kconfig
new file mode 100644
index 000000000000..14246fc2fb02
--- /dev/null
+++ b/drivers/virt/coco/tdx-guest/Kconfig
@@ -0,0 +1,10 @@
+config TDX_GUEST_DRIVER
+ tristate "TDX Guest driver"
+ depends on INTEL_TDX_GUEST
+ help
+ The driver provides userspace interface to communicate with
+ the TDX module to request the TDX guest details like attestation
+ report.
+
+ To compile this driver as module, choose M here. The module will
+ be called tdx-guest.
diff --git a/drivers/virt/coco/tdx-guest/Makefile b/drivers/virt/coco/tdx-guest/Makefile
new file mode 100644
index 000000000000..775cb463f9c8
--- /dev/null
+++ b/drivers/virt/coco/tdx-guest/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_TDX_GUEST_DRIVER) += tdx-guest.o
diff --git a/drivers/virt/coco/tdx-guest/tdx-guest.c b/drivers/virt/coco/tdx-guest/tdx-guest.c
new file mode 100644
index 000000000000..5e44a0fa69bd
--- /dev/null
+++ b/drivers/virt/coco/tdx-guest/tdx-guest.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TDX guest user interface driver
+ *
+ * Copyright (C) 2022 Intel Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+
+#include <uapi/linux/tdx-guest.h>
+
+#include <asm/cpu_device_id.h>
+#include <asm/tdx.h>
+
+static long tdx_get_report0(struct tdx_report_req __user *req)
+{
+ u8 *reportdata, *tdreport;
+ long ret;
+
+ reportdata = kmalloc(TDX_REPORTDATA_LEN, GFP_KERNEL);
+ if (!reportdata)
+ return -ENOMEM;
+
+ tdreport = kzalloc(TDX_REPORT_LEN, GFP_KERNEL);
+ if (!tdreport) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (copy_from_user(reportdata, req->reportdata, TDX_REPORTDATA_LEN)) {
+ ret = -EFAULT;
+ goto out;
+ }
+
+ /* Generate TDREPORT0 using "TDG.MR.REPORT" TDCALL */
+ ret = tdx_mcall_get_report0(reportdata, tdreport);
+ if (ret)
+ goto out;
+
+ if (copy_to_user(req->tdreport, tdreport, TDX_REPORT_LEN))
+ ret = -EFAULT;
+
+out:
+ kfree(reportdata);
+ kfree(tdreport);
+
+ return ret;
+}
+
+static long tdx_guest_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ switch (cmd) {
+ case TDX_CMD_GET_REPORT0:
+ return tdx_get_report0((struct tdx_report_req __user *)arg);
+ default:
+ return -ENOTTY;
+ }
+}
+
+static const struct file_operations tdx_guest_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = tdx_guest_ioctl,
+ .llseek = no_llseek,
+};
+
+static struct miscdevice tdx_misc_dev = {
+ .name = KBUILD_MODNAME,
+ .minor = MISC_DYNAMIC_MINOR,
+ .fops = &tdx_guest_fops,
+};
+
+static const struct x86_cpu_id tdx_guest_ids[] = {
+ X86_MATCH_FEATURE(X86_FEATURE_TDX_GUEST, NULL),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, tdx_guest_ids);
+
+static int __init tdx_guest_init(void)
+{
+ if (!x86_match_cpu(tdx_guest_ids))
+ return -ENODEV;
+
+ return misc_register(&tdx_misc_dev);
+}
+module_init(tdx_guest_init);
+
+static void __exit tdx_guest_exit(void)
+{
+ misc_deregister(&tdx_misc_dev);
+}
+module_exit(tdx_guest_exit);
+
+MODULE_AUTHOR("Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>");
+MODULE_DESCRIPTION("TDX Guest Driver");
+MODULE_LICENSE("GPL");