Merge tag 'x86_sgx_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SGC support from Borislav Petkov:
 "Intel Software Guard eXtensions enablement. This has been long in the
  making, we were one revision number short of 42. :)

  Intel SGX is new hardware functionality that can be used by
  applications to populate protected regions of user code and data
  called enclaves. Once activated, the new hardware protects enclave
  code and data from outside access and modification.

  Enclaves provide a place to store secrets and process data with those
  secrets. SGX has been used, for example, to decrypt video without
  exposing the decryption keys to nosy debuggers that might be used to
  subvert DRM. Software has generally been rewritten specifically to run
  in enclaves, but there are also projects that try to run limited
  unmodified software in enclaves.

  Most of the functionality is concentrated into arch/x86/kernel/cpu/sgx/
  except the addition of a new mprotect() hook to control enclave page
  permissions and support for vDSO exceptions fixup which will is used
  by SGX enclaves.

  All this work by Sean Christopherson, Jarkko Sakkinen and many others"

* tag 'x86_sgx_for_v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  x86/sgx: Return -EINVAL on a zero length buffer in sgx_ioc_enclave_add_pages()
  x86/sgx: Fix a typo in kernel-doc markup
  x86/sgx: Fix sgx_ioc_enclave_provision() kernel-doc comment
  x86/sgx: Return -ERESTARTSYS in sgx_ioc_enclave_add_pages()
  selftests/sgx: Use a statically generated 3072-bit RSA key
  x86/sgx: Clarify 'laundry_list' locking
  x86/sgx: Update MAINTAINERS
  Documentation/x86: Document SGX kernel architecture
  x86/sgx: Add ptrace() support for the SGX driver
  x86/sgx: Add a page reclaimer
  selftests/x86: Add a selftest for SGX
  x86/vdso: Implement a vDSO for Intel SGX enclave call
  x86/traps: Attempt to fixup exceptions in vDSO before signaling
  x86/fault: Add a helper function to sanitize error code
  x86/vdso: Add support for exception fixup in vDSO functions
  x86/sgx: Add SGX_IOC_ENCLAVE_PROVISION
  x86/sgx: Add SGX_IOC_ENCLAVE_INIT
  x86/sgx: Add SGX_IOC_ENCLAVE_ADD_PAGES
  x86/sgx: Add SGX_IOC_ENCLAVE_CREATE
  x86/sgx: Add an SGX misc driver interface
  ...

1 files changed, 168 insertions, 0 deletions

diff --git a/arch/x86/include/uapi/asm/sgx.h b/arch/x86/include/uapi/asm/sgx.h
new file mode 100644
index 000000000000..9034f3007c4e
--- /dev/null
+++ b/arch/x86/include/uapi/asm/sgx.h
@@ -0,0 +1,168 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright(c) 2016-20 Intel Corporation.
+ */
+#ifndef _UAPI_ASM_X86_SGX_H
+#define _UAPI_ASM_X86_SGX_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/**
+ * enum sgx_page_flags - page control flags
+ * %SGX_PAGE_MEASURE:	Measure the page contents with a sequence of
+ *			ENCLS[EEXTEND] operations.
+ */
+enum sgx_page_flags {
+	SGX_PAGE_MEASURE	= 0x01,
+};
+
+#define SGX_MAGIC 0xA4
+
+#define SGX_IOC_ENCLAVE_CREATE \
+	_IOW(SGX_MAGIC, 0x00, struct sgx_enclave_create)
+#define SGX_IOC_ENCLAVE_ADD_PAGES \
+	_IOWR(SGX_MAGIC, 0x01, struct sgx_enclave_add_pages)
+#define SGX_IOC_ENCLAVE_INIT \
+	_IOW(SGX_MAGIC, 0x02, struct sgx_enclave_init)
+#define SGX_IOC_ENCLAVE_PROVISION \
+	_IOW(SGX_MAGIC, 0x03, struct sgx_enclave_provision)
+
+/**
+ * struct sgx_enclave_create - parameter structure for the
+ *                             %SGX_IOC_ENCLAVE_CREATE ioctl
+ * @src:	address for the SECS page data
+ */
+struct sgx_enclave_create  {
+	__u64	src;
+};
+
+/**
+ * struct sgx_enclave_add_pages - parameter structure for the
+ *                                %SGX_IOC_ENCLAVE_ADD_PAGE ioctl
+ * @src:	start address for the page data
+ * @offset:	starting page offset
+ * @length:	length of the data (multiple of the page size)
+ * @secinfo:	address for the SECINFO data
+ * @flags:	page control flags
+ * @count:	number of bytes added (multiple of the page size)
+ */
+struct sgx_enclave_add_pages {
+	__u64 src;
+	__u64 offset;
+	__u64 length;
+	__u64 secinfo;
+	__u64 flags;
+	__u64 count;
+};
+
+/**
+ * struct sgx_enclave_init - parameter structure for the
+ *                           %SGX_IOC_ENCLAVE_INIT ioctl
+ * @sigstruct:	address for the SIGSTRUCT data
+ */
+struct sgx_enclave_init {
+	__u64 sigstruct;
+};
+
+/**
+ * struct sgx_enclave_provision - parameter structure for the
+ *				  %SGX_IOC_ENCLAVE_PROVISION ioctl
+ * @fd:		file handle of /dev/sgx_provision
+ */
+struct sgx_enclave_provision {
+	__u64 fd;
+};
+
+struct sgx_enclave_run;
+
+/**
+ * typedef sgx_enclave_user_handler_t - Exit handler function accepted by
+ *					__vdso_sgx_enter_enclave()
+ * @run:	The run instance given by the caller
+ *
+ * The register parameters contain the snapshot of their values at enclave
+ * exit. An invalid ENCLU function number will cause -EINVAL to be returned
+ * to the caller.
+ *
+ * Return:
+ * - <= 0:	The given value is returned back to the caller.
+ * - > 0:	ENCLU function to invoke, either EENTER or ERESUME.
+ */
+typedef int (*sgx_enclave_user_handler_t)(long rdi, long rsi, long rdx,
+					  long rsp, long r8, long r9,
+					  struct sgx_enclave_run *run);
+
+/**
+ * struct sgx_enclave_run - the execution context of __vdso_sgx_enter_enclave()
+ * @tcs:			TCS used to enter the enclave
+ * @function:			The last seen ENCLU function (EENTER, ERESUME or EEXIT)
+ * @exception_vector:		The interrupt vector of the exception
+ * @exception_error_code:	The exception error code pulled out of the stack
+ * @exception_addr:		The address that triggered the exception
+ * @user_handler:		User provided callback run on exception
+ * @user_data:			Data passed to the user handler
+ * @reserved			Reserved for future extensions
+ *
+ * If @user_handler is provided, the handler will be invoked on all return paths
+ * of the normal flow.  The user handler may transfer control, e.g. via a
+ * longjmp() call or a C++ exception, without returning to
+ * __vdso_sgx_enter_enclave().
+ */
+struct sgx_enclave_run {
+	__u64 tcs;
+	__u32 function;
+	__u16 exception_vector;
+	__u16 exception_error_code;
+	__u64 exception_addr;
+	__u64 user_handler;
+	__u64 user_data;
+	__u8  reserved[216];
+};
+
+/**
+ * typedef vdso_sgx_enter_enclave_t - Prototype for __vdso_sgx_enter_enclave(),
+ *				      a vDSO function to enter an SGX enclave.
+ * @rdi:	Pass-through value for RDI
+ * @rsi:	Pass-through value for RSI
+ * @rdx:	Pass-through value for RDX
+ * @function:	ENCLU function, must be EENTER or ERESUME
+ * @r8:		Pass-through value for R8
+ * @r9:		Pass-through value for R9
+ * @run:	struct sgx_enclave_run, must be non-NULL
+ *
+ * NOTE: __vdso_sgx_enter_enclave() does not ensure full compliance with the
+ * x86-64 ABI, e.g. doesn't handle XSAVE state.  Except for non-volatile
+ * general purpose registers, EFLAGS.DF, and RSP alignment, preserving/setting
+ * state in accordance with the x86-64 ABI is the responsibility of the enclave
+ * and its runtime, i.e. __vdso_sgx_enter_enclave() cannot be called from C
+ * code without careful consideration by both the enclave and its runtime.
+ *
+ * All general purpose registers except RAX, RBX and RCX are passed as-is to the
+ * enclave.  RAX, RBX and RCX are consumed by EENTER and ERESUME and are loaded
+ * with @function, asynchronous exit pointer, and @run.tcs respectively.
+ *
+ * RBP and the stack are used to anchor __vdso_sgx_enter_enclave() to the
+ * pre-enclave state, e.g. to retrieve @run.exception and @run.user_handler
+ * after an enclave exit.  All other registers are available for use by the
+ * enclave and its runtime, e.g. an enclave can push additional data onto the
+ * stack (and modify RSP) to pass information to the optional user handler (see
+ * below).
+ *
+ * Most exceptions reported on ENCLU, including those that occur within the
+ * enclave, are fixed up and reported synchronously instead of being delivered
+ * via a standard signal. Debug Exceptions (#DB) and Breakpoints (#BP) are
+ * never fixed up and are always delivered via standard signals. On synchrously
+ * reported exceptions, -EFAULT is returned and details about the exception are
+ * recorded in @run.exception, the optional sgx_enclave_exception struct.
+ *
+ * Return:
+ * - 0:		ENCLU function was successfully executed.
+ * - -EINVAL:	Invalid ENCL number (neither EENTER nor ERESUME).
+ */
+typedef int (*vdso_sgx_enter_enclave_t)(unsigned long rdi, unsigned long rsi,
+					unsigned long rdx, unsigned int function,
+					unsigned long r8,  unsigned long r9,
+					struct sgx_enclave_run *run);
+
+#endif /* _UAPI_ASM_X86_SGX_H */