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
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
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
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
-
-
-
+
-
-
-
-
-
+
+
+
-
-
+
+
-
-
+
+
-
+
-
-
+
+
-
-
-
-
+
+
+
+
-
-
+
+
-
-
-
+
+
+
-
+
-
-
-
-
+
+
+
+
-
-
-
+
+
+
-
+
-
-
-
-
+
+
+
+
-
-
-
-
+
+
+
+
-
-
+
+
-
+
-
+
|
/*
* Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017,
* 2018, 2019, 2020
* Jonathan Schleifer <js@nil.im>
.intel_syntax noprefix
mov edx, [esp+4]
test edx, edx
jz short ret_nil
movl 4(%esp), %edx
testl %edx, %edx
jz ret_nil
bt edx, 0
jc short .Ltagged_pointer_\name
testb $1, %dl
jnz .Ltagged_pointer_\name
mov edx, [edx]
mov edx, [edx+32]
movl (%edx), %edx
movl 32(%edx), %edx
.Lmain_\name:
mov eax, [esp+8]
movl 8(%esp), %eax
#ifdef OF_SELUID24
movzx ecx, byte ptr [eax+2]
mov edx, [edx+ecx*4]
movzbl 2(%eax), %ecx
movl (%edx,%ecx,4), %edx
#endif
movzx ecx, byte ptr [eax+1]
mov edx, [edx+ecx*4]
movzx ecx, byte ptr [eax]
mov eax, [edx+ecx*4]
movzbl 1(%eax), %ecx
movl (%edx,%ecx,4), %edx
movzbl (%eax), %ecx
movl (%edx,%ecx,4), %eax
test eax, eax
jz short 0f
testl %eax, %eax
jz 0f
ret
0:
call get_eip
add eax, offset _GLOBAL_OFFSET_TABLE_
lea eax, [eax+\not_found@GOTOFF]
jmp eax
addl $_GLOBAL_OFFSET_TABLE_, %eax
lea \not_found@GOTOFF(%eax), %eax
jmp *%eax
.Ltagged_pointer_\name:
call get_eip
add eax, offset _GLOBAL_OFFSET_TABLE_
addl $_GLOBAL_OFFSET_TABLE_, %eax
lea ecx, [eax+objc_tagged_pointer_secret@GOTOFF]
xor edx, [ecx]
and dl, 0xE
movzx edx, dl
leal objc_tagged_pointer_secret@GOTOFF(%eax), %ecx
xorl (%ecx), %edx
andb $0xE, %dl
movzbl %dl, %edx
lea eax, [eax+objc_tagged_pointer_classes@GOTOFF]
mov edx, [eax+edx*2]
mov edx, [edx+32]
leal objc_tagged_pointer_classes@GOTOFF(%eax), %eax
movl (%eax,%edx,2), %edx
movl 32(%edx), %edx
jmp short .Lmain_\name
jmp .Lmain_\name
.type \name, %function
.size \name, .-\name
.endm
.macro generate_lookup_super name lookup
\name:
mov edx, [esp+4]
mov eax, [edx]
test eax, eax
jz short ret_nil
movl 4(%esp), %edx
movl (%edx), %eax
testl %eax, %eax
jz ret_nil
mov [esp+4], eax
mov edx, [edx+4]
mov edx, [edx+32]
jmp short .Lmain_\lookup
movl %eax, 4(%esp)
mov 4(%edx), %edx
mov 32(%edx), %edx
jmp .Lmain_\lookup
.type \name, %function
.size \name, .-\name
.endm
generate_lookup objc_msg_lookup objc_method_not_found
generate_lookup objc_msg_lookup_stret objc_method_not_found_stret
generate_lookup_super objc_msg_lookup_super objc_msg_lookup
generate_lookup_super objc_msg_lookup_super_stret objc_msg_lookup_stret
ret_nil:
call get_eip
add eax, offset _GLOBAL_OFFSET_TABLE_
lea eax, [eax+nil_method@GOTOFF]
addl $_GLOBAL_OFFSET_TABLE_, %eax
leal nil_method@GOTOFF(%eax), %eax
ret
nil_method:
xor eax, eax
xorl %eax, %eax
ret
get_eip:
mov eax, [esp]
movl (%esp), %eax
ret
#ifdef OF_LINUX
.section .note.GNU-stack, "", %progbits
#endif
|