MdePkg/BaseLib: Add Shadow Stack Support for X86.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1521

This patch adds SSP - shadow stack pointer to JumpBuffer.
It will be used for the platform that enabled CET/ShadowStack.

We add gEfiMdePkgTokenSpaceGuid.PcdControlFlowEnforcementPropertyMask
to control the global enable/disable.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Yao Jiewen <jiewen.yao@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>

MdePkg/Include/Library/BaseLib.h

@@ -31,6 +31,7 @@ typedef struct {
   UINT32                            Ebp;
   UINT32                            Esp;
   UINT32                            Eip;
+  UINT32                            Ssp;
 } BASE_LIBRARY_JUMP_BUFFER;
 
 #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 4
@@ -54,6 +55,7 @@ typedef struct {
   UINT64                            Rip;
   UINT64                            MxCsr;
   UINT8                             XmmBuffer[160]; ///< XMM6-XMM15.
+  UINT64                            Ssp;
 } BASE_LIBRARY_JUMP_BUFFER;
 
 #define BASE_LIBRARY_JUMP_BUFFER_ALIGNMENT 8

MdePkg/Library/BaseLib/BaseLib.inf

@@ -1,7 +1,7 @@
 ## @file
 #  Base Library implementation.
 #
-#  Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>
+#  Copyright (c) 2007 - 2019, Intel Corporation. All rights reserved.<BR>
 #  Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
 #  Portions copyright (c) 2011 - 2013, ARM Ltd. All rights reserved.<BR>
 #
@@ -620,6 +620,7 @@
   gEfiMdePkgTokenSpaceGuid.PcdMaximumLinkedListLength      ## SOMETIMES_CONSUMES
   gEfiMdePkgTokenSpaceGuid.PcdMaximumAsciiStringLength     ## SOMETIMES_CONSUMES
   gEfiMdePkgTokenSpaceGuid.PcdMaximumUnicodeStringLength   ## SOMETIMES_CONSUMES
+  gEfiMdePkgTokenSpaceGuid.PcdControlFlowEnforcementPropertyMask   ## SOMETIMES_CONSUMES
 
 [FeaturePcd]
   gEfiMdePkgTokenSpaceGuid.PcdVerifyNodeInList  ## CONSUMES

MdePkg/Library/BaseLib/Ia32/LongJump.c

@@ -1,7 +1,7 @@
 /** @file
   Implementation of _LongJump() on IA-32.
 
-  Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
   which accompanies this distribution.  The full text of the license may be found at
@@ -36,6 +36,32 @@ InternalLongJump (
   )
 {
   _asm {
+    mov     eax, [PcdGet32 (PcdControlFlowEnforcementPropertyMask)]
+    test    eax, eax
+    jz      CetDone
+    _emit      0x0F
+    _emit      0x20
+    _emit      0xE0                ; mov     eax, cr4
+    bt      eax, 23                ; check if CET is enabled
+    jnc     CetDone
+
+    mov     edx, [esp + 4]         ; edx = JumpBuffer
+    mov     edx, [edx + 24]        ; edx = target SSP
+    _emit      0xF3
+    _emit      0x0F
+    _emit      0x1E
+    _emit      0xC8                ; READSSP EAX
+    sub     edx, eax               ; edx = delta
+    mov     eax, edx               ; eax = delta
+
+    shr     eax, 2                 ; eax = delta/sizeof(UINT32)
+    _emit      0xF3
+    _emit      0x0F
+    _emit      0xAE
+    _emit      0xE8                ; INCSSP EAX
+
+CetDone:
+
     pop     eax                         ; skip return address
     pop     edx                         ; edx <- JumpBuffer
     pop     eax                         ; eax <- Value

MdePkg/Library/BaseLib/Ia32/LongJump.nasm

@@ -1,6 +1,6 @@
 ;------------------------------------------------------------------------------
 ;
-; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
 ; This program and the accompanying materials
 ; are licensed and made available under the terms and conditions of the BSD License
 ; which accompanies this distribution.  The full text of the license may be found at
@@ -19,8 +19,12 @@
 ;
 ;------------------------------------------------------------------------------
 
+%include "Nasm.inc"
+
     SECTION .text
 
+extern ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))
+
 ;------------------------------------------------------------------------------
 ; VOID
 ; EFIAPI
@@ -31,6 +35,25 @@
 ;------------------------------------------------------------------------------
 global ASM_PFX(InternalLongJump)
 ASM_PFX(InternalLongJump):
+
+    mov     eax, [ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))]
+    test    eax, eax
+    jz      CetDone
+    mov     eax, cr4
+    bt      eax, 23                ; check if CET is enabled
+    jnc     CetDone
+
+    mov     edx, [esp + 4]         ; edx = JumpBuffer
+    mov     edx, [edx + 24]        ; edx = target SSP
+    READSSP_EAX
+    sub     edx, eax               ; edx = delta
+    mov     eax, edx               ; eax = delta
+
+    shr     eax, 2                 ; eax = delta/sizeof(UINT32)
+    INCSSP_EAX
+
+CetDone:
+
     pop     eax                         ; skip return address
     pop     edx                         ; edx <- JumpBuffer
     pop     eax                         ; eax <- Value

MdePkg/Library/BaseLib/Ia32/SetJump.c

@@ -1,7 +1,7 @@
 /** @file
   Implementation of SetJump() on IA-32.
 
-  Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
   which accompanies this distribution.  The full text of the license may be found at
@@ -62,6 +62,32 @@ SetJump (
     pop     ecx
     pop     ecx
     mov     edx, [esp]
+
+    xor     eax, eax
+    mov     [edx + 24], eax        ; save 0 to SSP
+
+    mov     eax, [PcdGet32 (PcdControlFlowEnforcementPropertyMask)]
+    test    eax, eax
+    jz      CetDone
+    _emit      0x0F
+    _emit      0x20
+    _emit      0xE0                ; mov     eax, cr4
+    bt      eax, 23                ; check if CET is enabled
+    jnc     CetDone
+
+    mov     eax, 1
+    _emit      0xF3
+    _emit      0x0F
+    _emit      0xAE
+    _emit      0xE8                ; INCSSP EAX to read original SSP
+    _emit      0xF3
+    _emit      0x0F
+    _emit      0x1E
+    _emit      0xC8                ; READSSP EAX
+    mov     [edx + 0x24], eax      ; save SSP
+
+CetDone:
+
     mov     [edx], ebx
     mov     [edx + 4], esi
     mov     [edx + 8], edi

MdePkg/Library/BaseLib/Ia32/SetJump.nasm

@@ -1,6 +1,6 @@
 ;------------------------------------------------------------------------------
 ;
-; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
 ; This program and the accompanying materials
 ; are licensed and made available under the terms and conditions of the BSD License
 ; which accompanies this distribution.  The full text of the license may be found at
@@ -19,9 +19,12 @@
 ;
 ;------------------------------------------------------------------------------
 
+%include "Nasm.inc"
+
     SECTION .text
 
 extern ASM_PFX(InternalAssertJumpBuffer)
+extern ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))
 
 ;------------------------------------------------------------------------------
 ; UINTN
@@ -37,6 +40,24 @@ ASM_PFX(SetJump):
     pop     ecx
     pop     ecx                         ; ecx <- return address
     mov     edx, [esp]
+
+    xor     eax, eax
+    mov     [edx + 24], eax        ; save 0 to SSP
+
+    mov     eax, [ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))]
+    test    eax, eax
+    jz      CetDone
+    mov     eax, cr4
+    bt      eax, 23                ; check if CET is enabled
+    jnc     CetDone
+
+    mov     eax, 1
+    INCSSP_EAX                     ; to read original SSP
+    READSSP_EAX
+    mov     [edx + 0x24], eax      ; save SSP
+
+CetDone:
+
     mov     [edx], ebx
     mov     [edx + 4], esi
     mov     [edx + 8], edi

MdePkg/Library/BaseLib/X64/LongJump.nasm

@@ -1,6 +1,6 @@
 ;------------------------------------------------------------------------------
 ;
-; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
 ; This program and the accompanying materials
 ; are licensed and made available under the terms and conditions of the BSD License
 ; which accompanies this distribution.  The full text of the license may be found at
@@ -19,9 +19,13 @@
 ;
 ;------------------------------------------------------------------------------
 
+%include "Nasm.inc"
+
     DEFAULT REL
     SECTION .text
 
+extern ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))
+
 ;------------------------------------------------------------------------------
 ; VOID
 ; EFIAPI
@@ -32,6 +36,27 @@
 ;------------------------------------------------------------------------------
 global ASM_PFX(InternalLongJump)
 ASM_PFX(InternalLongJump):
+
+    mov     eax, [ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))]
+    test    eax, eax
+    jz      CetDone
+    mov     rax, cr4
+    bt      eax, 23                      ; check if CET is enabled
+    jnc     CetDone
+
+    push    rdx                          ; save rdx
+
+    mov     rdx, [rcx + 0xF8]            ; rdx = target SSP
+    READSSP_RAX
+    sub     rdx, rax                     ; rdx = delta
+    mov     rax, rdx                     ; rax = delta
+
+    shr     rax, 3                       ; rax = delta/sizeof(UINT64)
+    INCSSP_RAX
+
+    pop     rdx                          ; restore rdx
+CetDone:
+
     mov     rbx, [rcx]
     mov     rsp, [rcx + 8]
     mov     rbp, [rcx + 0x10]

MdePkg/Library/BaseLib/X64/SetJump.nasm

@@ -1,6 +1,6 @@
 ;------------------------------------------------------------------------------
 ;
-; Copyright (c) 2006, Intel Corporation. All rights reserved.<BR>
+; Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
 ; This program and the accompanying materials
 ; are licensed and made available under the terms and conditions of the BSD License
 ; which accompanies this distribution.  The full text of the license may be found at
@@ -19,10 +19,13 @@
 ;
 ;------------------------------------------------------------------------------
 
+%include "Nasm.inc"
+
     DEFAULT REL
     SECTION .text
 
 extern ASM_PFX(InternalAssertJumpBuffer)
+extern ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))
 
 ;------------------------------------------------------------------------------
 ; UINTN
@@ -39,6 +42,24 @@ ASM_PFX(SetJump):
     add     rsp, 0x20
     pop     rcx
     pop     rdx
+
+    xor     rax, rax
+    mov     [rcx + 0xF8], rax            ; save 0 to SSP
+
+    mov     eax, [ASM_PFX(PcdGet32 (PcdControlFlowEnforcementPropertyMask))]
+    test    eax, eax
+    jz      CetDone
+    mov     rax, cr4
+    bt      eax, 23                      ; check if CET is enabled
+    jnc     CetDone
+
+    mov     rax, 1
+    INCSSP_RAX                           ; to read original SSP
+    READSSP_RAX
+    mov     [rcx + 0xF8], rax            ; save SSP
+
+CetDone:
+
     mov     [rcx], rbx
     mov     [rcx + 8], rsp
     mov     [rcx + 0x10], rbp

MdePkg/MdePkg.dec

@@ -2087,6 +2087,13 @@
   # @Prompt Fixed Debug Message Print Level.
   gEfiMdePkgTokenSpaceGuid.PcdFixedDebugPrintErrorLevel|0xFFFFFFFF|UINT32|0x30001016
 
+  ## Indicates the control flow enforcement enabling state.
+  #  If enabled, it uses control flow enforcement technology to prevent ROP or JOP.<BR><BR>
+  #   BIT0 - SMM CET Shadow Stack is enabled.<BR>
+  #   Other - reserved
+  # @Prompt Enable control flow enforcement.
+  gEfiMdePkgTokenSpaceGuid.PcdControlFlowEnforcementPropertyMask|0x0|UINT32|0x30001017
+
 [PcdsFixedAtBuild,PcdsPatchableInModule]
   ## Indicates the maximum length of unicode string used in the following
   #  BaseLib functions: StrLen(), StrSize(), StrCmp(), StrnCmp(), StrCpy(), StrnCpy()<BR><BR>