1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
|
;; Licensed to the .NET Foundation under one or more agreements.
;; The .NET Foundation licenses this file to you under the MIT license.
;; See the LICENSE file in the project root for more information.
#include "ksarm64.h"
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; DATA SECTIONS ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
POINTER_SIZE equ 0x08
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ConstrainedCall Support Helpers ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; Note: The "__jmpstub__" prefix is used to indicate to debugger
;; that it must step-through this stub when it encounters it while
;; stepping.
;;
;; INPUT: xip0: AddressOfAddressOfFunctionToCallAfterDereferencingThis
;;
LEAF_ENTRY __jmpstub__ConstrainedCallSupport_DerefThisAndCall_CommonCallingStub
ldr x12, [xip0] ; Load tail jump target
ldr x0, [x0] ; Dereference this to get real function pointer
ret x12
LEAF_END __jmpstub__ConstrainedCallSupport_DerefThisAndCall_CommonCallingStub
;;
;; void ConstrainedCallSupport_GetStubs(IntPtr *__jmpstub__ConstrainedCallSupport_DerefThisAndCall_CommonCallingStub,
;; IntPtr *__jmpstub__ConstrainedCallSupport_DirectConstrainedCallCommonStub)
;;
LEAF_ENTRY ConstrainedCallSupport_GetStubs
ldr x12, =__jmpstub__ConstrainedCallSupport_DerefThisAndCall_CommonCallingStub
str x12, [x0]
ldr x12, =__jmpstub__ConstrainedCallSupport_DirectConstrainedCallCommonStub
str x12, [x1]
ret
LEAF_END ConstrainedCallSupport_GetStubs
;;
;; __jmpstub__ConstrainedCallSupport_DirectConstrainedCallCommonStub
;;
;; struct ConstrainedCallDesc
;; {
;; ULONG_PTR ExactTarget;
;; ULONG_PTR LookupFunc; // Put UniversalThunk here
;; }
;;
;; struct CommonCallingStubInputData
;; {
;; ULONG_PTR ConstrainedCallDesc;
;; ULONG_PTR DirectConstrainedCallResolver;
;; }
;;
;; INPUT: xip0: Points at CommonCallingStubInputData
;;
;;
LEAF_ENTRY __jmpstub__ConstrainedCallSupport_DirectConstrainedCallCommonStub
ldr xip1, [xip0] ; put ConstrainedCallDesc into xip1 (Arg to LookupFunc/Temp for getting ExactTarget)
ldr x12, [xip1] ; put ExactTarget into x12
cbnz x12, JumpToTarget ; compare against null
; If we reach here, we need to use a universal thunk to call the LookupFunc
ldr x12, [xip1, #POINTER_SIZE] ; Get Universal thunk function pointer into x12
ldr xip0, [xip0, #POINTER_SIZE] ; Put DirectConstrainedCallResolver into xip0 for UniversalTransitionThunk call
JumpToTarget
ret x12
LEAF_END __jmpstub__ConstrainedCallSupport_DirectConstrainedCallCommonStub
END
|
