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
|
/* vi: set sw=4 ts=4: */
/* yoinked from glibc/sysdeps/x86_64/dl-machine.h */
/* Machine-dependent ELF dynamic relocation inline functions. x86-64 version.
Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Andreas Jaeger <aj@suse.de>.
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
<http://www.gnu.org/licenses/>. */
/* Define this if the system uses RELOCA. */
#define ELF_USES_RELOCA
#include <elf.h>
#include <link.h>
/* Initialization sequence for the GOT. */
#define INIT_GOT(GOT_BASE,MODULE) \
do { \
GOT_BASE[2] = (unsigned long) _dl_linux_resolve; \
GOT_BASE[1] = (unsigned long) MODULE; \
} while(0)
/* Here we define the magic numbers that this dynamic loader should accept */
#define MAGIC1 EM_X86_64
#undef MAGIC2
/* Used for error messages */
#define ELF_TARGET "x86_64"
struct elf_resolve;
extern unsigned long _dl_linux_resolver(struct elf_resolve * tpnt, int reloc_entry);
/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
TLS variable, so undefined references should not be allowed to
define the value.
ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve to one
of the main executable's symbols, as for a COPY reloc. */
#define elf_machine_type_class(type) \
((((type) == R_X86_64_JUMP_SLOT \
|| (type) == R_X86_64_DTPMOD64 \
|| (type) == R_X86_64_DTPOFF64 \
|| (type) == R_X86_64_TPOFF64) \
* ELF_RTYPE_CLASS_PLT) \
| (((type) == R_X86_64_COPY) * ELF_RTYPE_CLASS_COPY))
/* Return the link-time address of _DYNAMIC. Conveniently, this is the
first element of the GOT. This must be inlined in a function which
uses global data. */
static __always_inline Elf64_Addr __attribute__ ((unused))
elf_machine_dynamic (void)
{
Elf64_Addr addr;
/* This works because we have our GOT address available in the small PIC
model. */
addr = (Elf64_Addr) &_DYNAMIC;
return addr;
}
/* Return the run-time load address of the shared object. */
static __always_inline Elf64_Addr __attribute__ ((unused))
elf_machine_load_address (void)
{
register Elf64_Addr addr, tmp;
/* The easy way is just the same as on x86:
leaq _dl_start, %0
leaq _dl_start(%%rip), %1
subq %0, %1
but this does not work with binutils since we then have
a R_X86_64_32S relocation in a shared lib.
Instead we store the address of _dl_start in the data section
and compare it with the current value that we can get via
an RIP relative addressing mode. */
__asm__ ("movq 1f(%%rip), %1\n"
"0:\tleaq _dl_start(%%rip), %0\n\t"
"subq %1, %0\n\t"
".section\t.data\n"
"1:\t.quad _dl_start\n\t"
".previous\n\t"
: "=r" (addr), "=r" (tmp) : : "cc");
return addr;
}
static __always_inline void
elf_machine_relative(Elf64_Addr load_off, const Elf64_Addr rel_addr,
Elf64_Word relative_count)
{
Elf64_Rela *rpnt = (Elf64_Rela*)rel_addr;
--rpnt;
do {
Elf64_Addr *const reloc_addr = (Elf64_Addr*)(load_off + (++rpnt)->r_offset);
*reloc_addr = load_off + rpnt->r_addend;
} while (--relative_count);
}
|