1 /* Common code for ebl reloc functions.
2 Copyright (C) 2005, 2006 Red Hat, Inc.
3 This file is part of elfutils.
4
5 This file is free software; you can redistribute it and/or modify
6 it under the terms of either
7
8 * the GNU Lesser General Public License as published by the Free
9 Software Foundation; either version 3 of the License, or (at
10 your option) any later version
11
12 or
13
14 * the GNU General Public License as published by the Free
15 Software Foundation; either version 2 of the License, or (at
16 your option) any later version
17
18 or both in parallel, as here.
19
20 elfutils is distributed in the hope that it will be useful, but
21 WITHOUT ANY WARRANTY; without even the implied warranty of
22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 General Public License for more details.
24
25 You should have received copies of the GNU General Public License and
26 the GNU Lesser General Public License along with this program. If
27 not, see <http://www.gnu.org/licenses/>. */
28
29 #include "libebl_CPU.h"
30 #include <assert.h>
31
32 #define R_TYPE(name) PASTE (RELOC_PREFIX, name)
33 #define PASTE(a, b) PASTE_1 (a, b)
34 #define PASTE_1(a, b) a##b
35 #define R_NAME(name) R_NAME_1 (RELOC_PREFIX, name)
36 #define R_NAME_1(prefix, type) R_NAME_2 (prefix, type)
37 #define R_NAME_2(prefix, type) #prefix #type
38
39 #define RELOC_TYPES STRINGIFIED_PASTE (BACKEND, reloc.def)
40 #define STRINGIFIED_PASTE(a, b) STRINGIFY (PASTE (a, b))
41 #define STRINGIFY(x) STRINGIFY_1 (x)
42 #define STRINGIFY_1(x) #x
43
44 /* Provide a table of reloc type names, in a PIC-friendly fashion. */
45
EBLHOOK(reloc_nametable)46 static const struct EBLHOOK(reloc_nametable)
47 {
48 char zero;
49 #define RELOC_TYPE(type, uses) \
50 char name_##type[sizeof R_NAME (type)];
51 #include RELOC_TYPES
52 #undef RELOC_TYPE
53 } EBLHOOK(reloc_nametable) =
54 {
55 '\0',
56 #define RELOC_TYPE(type, uses) R_NAME (type),
57 #include RELOC_TYPES
58 #undef RELOC_TYPE
59 };
60 #define reloc_namestr (&EBLHOOK(reloc_nametable).zero)
61
62 static const uint_fast16_t EBLHOOK(reloc_nameidx)[] =
63 {
64 #define RELOC_TYPE(type, uses) \
65 [R_TYPE (type)] = offsetof (struct EBLHOOK(reloc_nametable), name_##type),
66 #include RELOC_TYPES
67 #undef RELOC_TYPE
68 };
69 #define nreloc \
70 ((int) (sizeof EBLHOOK(reloc_nameidx) / sizeof EBLHOOK(reloc_nameidx)[0]))
71
72 #define REL (1 << (ET_REL - 1))
73 #define EXEC (1 << (ET_EXEC - 1))
74 #define DYN (1 << (ET_DYN - 1))
75 static const uint8_t EBLHOOK(reloc_valid)[] =
76 {
77 #define RELOC_TYPE(type, uses) [R_TYPE (type)] = uses,
78 #include RELOC_TYPES
79 #undef RELOC_TYPE
80 };
81 #undef REL
82 #undef EXEC
83 #undef DYN
84
85 const char *
EBLHOOK(reloc_type_name)86 EBLHOOK(reloc_type_name) (int reloc,
87 char *buf __attribute__ ((unused)),
88 size_t len __attribute__ ((unused)))
89 {
90 if (reloc >= 0 && reloc < nreloc && EBLHOOK(reloc_nameidx)[reloc] != 0)
91 return &reloc_namestr[EBLHOOK(reloc_nameidx)[reloc]];
92 return NULL;
93 }
94
95 bool
EBLHOOK(reloc_type_check)96 EBLHOOK(reloc_type_check) (int reloc)
97 {
98 return reloc >= 0 && reloc < nreloc && EBLHOOK(reloc_nameidx)[reloc] != 0;
99 }
100
101 bool
EBLHOOK(reloc_valid_use)102 EBLHOOK(reloc_valid_use) (Elf *elf, int reloc)
103 {
104 uint8_t uses = EBLHOOK(reloc_valid)[reloc];
105
106 GElf_Ehdr ehdr_mem;
107 GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem);
108 assert (ehdr != NULL);
109 uint8_t type = ehdr->e_type;
110
111 return type > ET_NONE && type < ET_CORE && (uses & (1 << (type - 1)));
112 }
113
114
115 bool
EBLHOOK(copy_reloc_p)116 EBLHOOK(copy_reloc_p) (int reloc)
117 {
118 return reloc == R_TYPE (COPY);
119 }
120
121 bool
EBLHOOK(none_reloc_p)122 EBLHOOK(none_reloc_p) (int reloc)
123 {
124 return reloc == R_TYPE (NONE);
125 }
126
127 #ifndef NO_RELATIVE_RELOC
128 bool
EBLHOOK(relative_reloc_p)129 EBLHOOK(relative_reloc_p) (int reloc)
130 {
131 return reloc == R_TYPE (RELATIVE);
132 }
133 #endif
134
135 static void
EBLHOOK(init_reloc)136 EBLHOOK(init_reloc) (Ebl *ebl)
137 {
138 ebl->reloc_type_name = EBLHOOK(reloc_type_name);
139 ebl->reloc_type_check = EBLHOOK(reloc_type_check);
140 ebl->reloc_valid_use = EBLHOOK(reloc_valid_use);
141 ebl->copy_reloc_p = EBLHOOK(copy_reloc_p);
142 ebl->none_reloc_p = EBLHOOK(none_reloc_p);
143 #ifndef NO_RELATIVE_RELOC
144 ebl->relative_reloc_p = EBLHOOK(relative_reloc_p);
145 #endif
146 }
147