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
|
/* Machine-dependent ELF dynamic relocation inline functions. Stub version.
Copyright (C) 1995-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#define ELF_MACHINE_NAME "stub"
#include <string.h>
#include <link.h>
/* Return nonzero iff ELF header is compatible with the running host. */
static inline int
elf_machine_matches_host (const Elf32_Ehdr *ehdr)
{
switch (ehdr->e_machine)
{
default:
return 0;
}
}
/* Return the link-time address of _DYNAMIC. */
static inline Elf32_Addr
elf_machine_dynamic (void)
{
#error "Damn, no _DYNAMIC"
}
/* Return the run-time load address of the shared object. */
static inline Elf32_Addr
elf_machine_load_address (void)
{
#error "Where am I?"
}
/* Fixup a PLT entry to bounce directly to the function at VALUE. */
static inline ElfW(Addr)
elf_machine_fixup_plt (struct link_map *map, lookup_t t,
const ElfW(Sym) *refsym, const ElfW(Sym) *sym,
const ElfW(Rel) *reloc,
ElfW(Addr) *reloc_addr, ElfW(Addr) value)
{
return *reloc_addr = value;
}
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
LOADADDR is the load address of the object; INFO is an array indexed
by DT_* of the .dynamic section info. */
auto inline void
__attribute__ ((always_inline))
elf_machine_rel (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
const Elf32_Rel *reloc, const Elf32_Sym *sym,
Elf32_Addr (*resolve) (const Elf32_Sym **ref,
Elf32_Addr reloc_addr,
int noplt))
{
Elf32_Addr *const reloc_addr = (Elf32_Addr *) reloc->r_offset;
Elf32_Addr loadbase;
switch (ELF32_R_TYPE (reloc->r_info))
{
case R_MACHINE_COPY:
loadbase = (*resolve) (&sym, (Elf32_Addr) reloc_addr, 0);
memcpy (reloc_addr, (void *) (loadbase + sym->st_value), sym->st_size);
break;
default:
_dl_reloc_bad_type (map, ELF32_R_TYPE (reloc->r_info), 0);
break;
}
}
auto inline Elf32_Addr
__attribute__ ((always_inline))
elf_machine_rela (Elf32_Addr loadaddr, Elf32_Dyn *info[DT_NUM],
const Elf32_Rel *reloc, const Elf32_Sym *sym,
Elf32_Addr (*resolve) (const Elf32_Sym **ref,
Elf32_Addr reloc_addr,
int noplt))
{
_dl_signal_error (0, "Elf32_Rela relocation requested -- unused on "
NULL, ELF_MACHINE_NAME);
}
/* Set up the loaded object described by L so its unrelocated PLT
entries will jump to the on-demand fixup code in dl-runtime.c. */
static inline int
elf_machine_runtime_setup (struct link_map *l, int lazy)
{
extern void _dl_runtime_resolve (Elf32_Word);
if (lazy)
{
/* The GOT entries for functions in the PLT have not yet been filled
in. Their initial contents will arrange when called to push an
offset into the .rel.plt section, push _GLOBAL_OFFSET_TABLE_[1],
and then jump to _GLOBAL_OFFSET_TABLE[2]. */
Elf32_Addr *got = (Elf32_Addr *) D_PTR (l, l_info[DT_PLTGOT]);
got[1] = (Elf32_Addr) l; /* Identify this shared object. */
/* This function will get called to fix up the GOT entry indicated by
the offset on the stack, and then jump to the resolved address. */
got[2] = (Elf32_Addr) &_dl_runtime_resolve;
}
return lazy;
}
/* Initial entry point code for the dynamic linker.
The C function `_dl_start' is the real entry point;
its return value is the user program's entry point. */
#define RTLD_START #error need some startup code
|
