dylink 0.11.0

Run-time dynamic linking loader utilities
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
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196

// SPDX-FileCopyrightText: 2022-2026 Jonathan A. Thomason <contact@jonathan-thomason.com>
// SPDX-License-Identifier: MIT OR Apache-2.0

#![allow(non_camel_case_types)]

use std::ffi;

type cpu_type_t = ffi::c_int;
type cpu_subtype_t = ffi::c_int;

// 32-bit header
#[repr(C)]
pub struct mach_header {
	pub magic: u32,
	pub cputype: cpu_type_t,
	pub cpusubtype: cpu_subtype_t,
	pub filetype: u32,
	pub ncmds: u32,
	pub sizeofcmds: u32,
	pub flags: u32,
}

// 64-bit header
#[repr(C)]
pub struct mach_header_64 {
	pub magic: u32,
	pub cputype: cpu_type_t,
	pub cpusubtype: cpu_subtype_t,
	pub filetype: u32,
	pub ncmds: u32,
	pub sizeofcmds: u32,
	pub flags: u32,
	pub reserved: u32,
}

#[cfg(target_os = "macos")]
pub type PfnImageCallback = extern "C" fn(mh: *const mach_header, vmaddr_slide: isize);

#[repr(C)]
pub struct Dl_info {
	pub dli_fname: *const ffi::c_char,
	pub dli_fbase: *mut ffi::c_void,
	pub dli_sname: *const ffi::c_char,
	pub dli_saddr: *mut ffi::c_void,
}

pub const RTLD_LOCAL: ffi::c_int = 0;
pub const RTLD_NOW: ffi::c_int = 0x2;
#[cfg(target_os = "macos")]
pub const RTLD_NOLOAD: ffi::c_int = 0x4;
#[cfg(target_env = "gnu")]
pub const RTLD_DI_LINKMAP: ffi::c_int = 2;
#[cfg(target_env = "gnu")]
pub type ElfW_Addr = usize;
#[cfg(target_pointer_width = "64")]
pub type Elf64_Xword = u64;

pub type ElfW_Half = u16;
pub type ElfW_Word = u32;

pub type Elf32_Off = u32;
pub type Elf64_Off = u64;

pub type Elf32_Addr = u32;

pub type Elf64_Addr = u64;

pub const ELFCLASS32: u8 = 1;
pub const ELFCLASS64: u8 = 2;

#[repr(C)]
pub struct Elf32_Ehdr {
	pub e_ident: [ffi::c_uchar; 16],
	pub e_type: ElfW_Half,
	pub e_machine: ElfW_Half,
	pub e_version: ElfW_Word,
	pub e_entry: Elf32_Addr,
	pub e_phoff: Elf32_Off,
	pub e_shoff: Elf32_Off,
	pub e_flags: ElfW_Word,
	pub e_ehsize: ElfW_Half,
	pub e_phentsize: ElfW_Half,
	pub e_phnum: ElfW_Half,
	pub e_shentsize: ElfW_Half,
	pub e_shnum: ElfW_Half,
	pub e_shstrndx: ElfW_Half,
}

#[repr(C)]
pub struct Elf64_Ehdr {
	pub e_ident: [ffi::c_uchar; 16],
	pub e_type: ElfW_Half,
	pub e_machine: ElfW_Half,
	pub e_version: ElfW_Word,
	pub e_entry: Elf64_Addr,
	pub e_phoff: Elf64_Off,
	pub e_shoff: Elf64_Off,
	pub e_flags: ElfW_Word,
	pub e_ehsize: ElfW_Half,
	pub e_phentsize: ElfW_Half,
	pub e_phnum: ElfW_Half,
	pub e_shentsize: ElfW_Half,
	pub e_shnum: ElfW_Half,
	pub e_shstrndx: ElfW_Half,
}

#[repr(C)]
pub struct Elf32_Phdr {
	pub p_type: ElfW_Word,
	pub p_offset: Elf32_Off,
	pub p_vaddr: Elf32_Addr,
	pub p_paddr: Elf32_Addr,
	pub p_filesz: ElfW_Word,
	pub p_memsz: ElfW_Word,
	pub p_flags: ElfW_Word,
	pub p_align: ElfW_Word,
}

#[cfg(target_pointer_width = "64")]
#[repr(C)]
pub struct Elf64_Phdr {
	pub p_type: ElfW_Word,
	pub p_flags: ElfW_Word,
	pub p_offset: Elf64_Off,
	pub p_vaddr: Elf64_Addr,
	pub p_paddr: Elf64_Addr,
	pub p_filesz: Elf64_Xword,
	pub p_memsz: Elf64_Xword,
	pub p_align: Elf64_Xword,
}

#[cfg(target_env = "gnu")]
#[repr(C)]
pub struct dl_phdr_info {
	pub dlpi_addr: ElfW_Addr,
	pub dlpi_name: *const ffi::c_char,
	#[cfg(target_pointer_width = "64")]
	pub dlpi_phdr: *const Elf64_Phdr,
	#[cfg(target_pointer_width = "32")]
	pub dlpi_phdr: *const Elf32_Phdr,
	pub dlpi_phnum: ElfW_Half,
}

unsafe extern "C" {
	pub fn dlopen(filename: *const ffi::c_char, flag: ffi::c_int) -> *mut ffi::c_void;
	pub fn dlerror() -> *const ffi::c_char;
	pub fn dlsym(handle: *mut ffi::c_void, symbol: *const ffi::c_char) -> *const ffi::c_void;
	pub fn dlclose(hlibmodule: *mut ffi::c_void) -> ffi::c_int;
	#[cfg(not(target_os = "aix"))]
	pub fn dladdr(addr: *const ffi::c_void, info: *mut Dl_info) -> ffi::c_int;
	#[cfg(target_env = "gnu")]
	pub fn dlinfo(
		handle: *mut ffi::c_void,
		request: ffi::c_int,
		info: *mut ffi::c_void,
	) -> ffi::c_int;
}

#[cfg(target_env = "gnu")]
pub type DlIteratePhdrCallback = unsafe extern "C" fn(
	info: *mut dl_phdr_info,
	size: usize,
	data: *mut ffi::c_void,
) -> ffi::c_int;

#[cfg(target_env = "gnu")]
unsafe extern "C" {
	pub fn dl_iterate_phdr(callback: DlIteratePhdrCallback, data: *mut ffi::c_void) -> ffi::c_int;
}

#[cfg(target_os = "macos")]
unsafe extern "C" {
	pub fn _dyld_get_image_name(image_index: u32) -> *const ffi::c_char;
	pub fn _dyld_register_func_for_add_image(func: PfnImageCallback);
	pub fn _dyld_register_func_for_remove_image(func: PfnImageCallback);
	// returns base address
	pub fn _dyld_get_image_header(image_index: u32) -> *const mach_header;
}

#[cfg(target_env = "gnu")]
#[repr(C)]
pub struct ElfW_Dyn {
	d_tag: usize,
	d_un: usize,
}

#[cfg(target_env = "gnu")]
#[repr(C)]
pub struct link_map {
	pub l_addr: usize,
	pub l_name: *mut ffi::c_char,
	pub l_ld: *mut ElfW_Dyn,
	pub l_next: *mut link_map,
	pub l_prev: *mut link_map,
	_marker: std::marker::PhantomPinned,
}