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
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
pub inline fn stubHelperPreambleSize(cpu_arch: std.Target.Cpu.Arch) u8 {
return switch (cpu_arch) {
.x86_64 => 15,
.aarch64 => 6 * @sizeOf(u32),
else => unreachable, // unhandled architecture type
};
}
pub inline fn stubHelperSize(cpu_arch: std.Target.Cpu.Arch) u8 {
return switch (cpu_arch) {
.x86_64 => 10,
.aarch64 => 3 * @sizeOf(u32),
else => unreachable, // unhandled architecture type
};
}
pub inline fn stubSize(cpu_arch: std.Target.Cpu.Arch) u8 {
return switch (cpu_arch) {
.x86_64 => 6,
.aarch64 => 3 * @sizeOf(u32),
else => unreachable, // unhandled architecture type
};
}
pub inline fn stubAlignment(cpu_arch: std.Target.Cpu.Arch) u8 {
return switch (cpu_arch) {
.x86_64 => 1,
.aarch64 => 4,
else => unreachable, // unhandled architecture type
};
}
pub inline fn stubOffsetInStubHelper(cpu_arch: std.Target.Cpu.Arch) u8 {
return switch (cpu_arch) {
.x86_64 => 1,
.aarch64 => 2 * @sizeOf(u32),
else => unreachable,
};
}
pub fn writeStubHelperPreambleCode(args: struct {
cpu_arch: std.Target.Cpu.Arch,
source_addr: u64,
dyld_private_addr: u64,
dyld_stub_binder_got_addr: u64,
}, writer: anytype) !void {
switch (args.cpu_arch) {
.x86_64 => {
try writer.writeAll(&.{ 0x4c, 0x8d, 0x1d });
{
const disp = try Relocation.calcPcRelativeDisplacementX86(
args.source_addr + 3,
args.dyld_private_addr,
0,
);
try writer.writeIntLittle(i32, disp);
}
try writer.writeAll(&.{ 0x41, 0x53, 0xff, 0x25 });
{
const disp = try Relocation.calcPcRelativeDisplacementX86(
args.source_addr + 11,
args.dyld_stub_binder_got_addr,
0,
);
try writer.writeIntLittle(i32, disp);
}
},
.aarch64 => {
{
const pages = Relocation.calcNumberOfPages(args.source_addr, args.dyld_private_addr);
try writer.writeIntLittle(u32, aarch64.Instruction.adrp(.x17, pages).toU32());
}
{
const off = try Relocation.calcPageOffset(args.dyld_private_addr, .arithmetic);
try writer.writeIntLittle(u32, aarch64.Instruction.add(.x17, .x17, off, false).toU32());
}
try writer.writeIntLittle(u32, aarch64.Instruction.stp(
.x16,
.x17,
aarch64.Register.sp,
aarch64.Instruction.LoadStorePairOffset.pre_index(-16),
).toU32());
{
const pages = Relocation.calcNumberOfPages(args.source_addr + 12, args.dyld_stub_binder_got_addr);
try writer.writeIntLittle(u32, aarch64.Instruction.adrp(.x16, pages).toU32());
}
{
const off = try Relocation.calcPageOffset(args.dyld_stub_binder_got_addr, .load_store_64);
try writer.writeIntLittle(u32, aarch64.Instruction.ldr(
.x16,
.x16,
aarch64.Instruction.LoadStoreOffset.imm(off),
).toU32());
}
try writer.writeIntLittle(u32, aarch64.Instruction.br(.x16).toU32());
},
else => unreachable,
}
}
pub fn writeStubHelperCode(args: struct {
cpu_arch: std.Target.Cpu.Arch,
source_addr: u64,
target_addr: u64,
}, writer: anytype) !void {
switch (args.cpu_arch) {
.x86_64 => {
try writer.writeAll(&.{ 0x68, 0x0, 0x0, 0x0, 0x0, 0xe9 });
{
const disp = try Relocation.calcPcRelativeDisplacementX86(args.source_addr + 6, args.target_addr, 0);
try writer.writeIntLittle(i32, disp);
}
},
.aarch64 => {
const stub_size: u4 = 3 * @sizeOf(u32);
const literal = blk: {
const div_res = try std.math.divExact(u64, stub_size - @sizeOf(u32), 4);
break :blk std.math.cast(u18, div_res) orelse return error.Overflow;
};
try writer.writeIntLittle(u32, aarch64.Instruction.ldrLiteral(
.w16,
literal,
).toU32());
{
const disp = try Relocation.calcPcRelativeDisplacementArm64(args.source_addr + 4, args.target_addr);
try writer.writeIntLittle(u32, aarch64.Instruction.b(disp).toU32());
}
try writer.writeAll(&.{ 0x0, 0x0, 0x0, 0x0 });
},
else => unreachable,
}
}
pub fn writeStubCode(args: struct {
cpu_arch: std.Target.Cpu.Arch,
source_addr: u64,
target_addr: u64,
}, writer: anytype) !void {
switch (args.cpu_arch) {
.x86_64 => {
try writer.writeAll(&.{ 0xff, 0x25 });
{
const disp = try Relocation.calcPcRelativeDisplacementX86(args.source_addr + 2, args.target_addr, 0);
try writer.writeIntLittle(i32, disp);
}
},
.aarch64 => {
{
const pages = Relocation.calcNumberOfPages(args.source_addr, args.target_addr);
try writer.writeIntLittle(u32, aarch64.Instruction.adrp(.x16, pages).toU32());
}
{
const off = try Relocation.calcPageOffset(args.target_addr, .load_store_64);
try writer.writeIntLittle(u32, aarch64.Instruction.ldr(
.x16,
.x16,
aarch64.Instruction.LoadStoreOffset.imm(off),
).toU32());
}
try writer.writeIntLittle(u32, aarch64.Instruction.br(.x16).toU32());
},
else => unreachable,
}
}
const std = @import("std");
const aarch64 = @import("../../arch/aarch64/bits.zig");
const Relocation = @import("Relocation.zig");
|
