mdreloc.c revision 1.11 1 /* $NetBSD: mdreloc.c,v 1.11 2002/09/12 20:21:01 mycroft Exp $ */
2
3 #include <sys/types.h>
4 #include <sys/stat.h>
5
6 #include "debug.h"
7 #include "rtld.h"
8
9 void _rtld_bind_start(void);
10
11 void
12 _rtld_setup_pltgot(const Obj_Entry *obj)
13 {
14 obj->pltgot[1] = (Elf_Addr) obj;
15 obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
16 }
17
18 int
19 _rtld_relocate_nonplt_objects(obj, self, dodebug)
20 const Obj_Entry *obj;
21 bool self;
22 bool dodebug;
23 {
24 const Elf_Rela *rela;
25
26 for (rela = obj->rela; rela < obj->relalim; rela++) {
27 Elf_Addr *where;
28 const Elf_Sym *def;
29 const Obj_Entry *defobj;
30 Elf_Addr tmp;
31 unsigned long symnum;
32
33 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
34 symnum = ELF_R_SYM(rela->r_info);
35
36 switch (ELF_R_TYPE(rela->r_info)) {
37 case R_TYPE(NONE):
38 break;
39
40 #if 1 /* XXX should not occur */
41 case R_TYPE(GOT32):
42 def = _rtld_find_symdef(symnum, obj, &defobj, false);
43 if (def == NULL)
44 return -1;
45
46 tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
47 rela->r_addend);
48 if (*where != tmp)
49 *where = tmp;
50 rdbg(dodebug, ("GOT32 %s in %s --> %p in %s",
51 obj->strtab + obj->symtab[symnum].st_name,
52 obj->path, (void *)*where, defobj->path));
53 break;
54
55 case R_TYPE(REL32):
56 def = _rtld_find_symdef(symnum, obj, &defobj, false);
57 if (def == NULL)
58 return -1;
59
60 *where += (Elf_Addr)(defobj->relocbase + def->st_value +
61 rela->r_addend) - (Elf_Addr)where;
62 rdbg(dodebug, ("PC32 %s in %s --> %p in %s",
63 obj->strtab + obj->symtab[symnum].st_name,
64 obj->path, (void *)*where, defobj->path));
65 break;
66 #endif
67
68 case R_TYPE(DIR32):
69 def = _rtld_find_symdef(symnum, obj, &defobj, false);
70 if (def == NULL)
71 return -1;
72
73 *where += (Elf_Addr)(defobj->relocbase + def->st_value +
74 rela->r_addend);
75 rdbg(dodebug, ("32 %s in %s --> %p in %s",
76 obj->strtab + obj->symtab[symnum].st_name,
77 obj->path, (void *)*where, defobj->path));
78 break;
79
80 case R_TYPE(GLOB_DAT):
81 def = _rtld_find_symdef(symnum, obj, &defobj, false);
82 if (def == NULL)
83 return -1;
84
85 tmp = (Elf_Addr)(defobj->relocbase + def->st_value) +
86 rela->r_addend;
87 if (*where != tmp)
88 *where = tmp;
89 rdbg(dodebug, ("GLOB_DAT %s in %s --> %p in %s",
90 obj->strtab + obj->symtab[symnum].st_name,
91 obj->path, (void *)*where, defobj->path));
92 break;
93
94 case R_TYPE(RELATIVE):
95 if (rela->r_addend)
96 *where = (Elf_Addr)obj->relocbase + rela->r_addend;
97 else
98 *where += (Elf_Addr)obj->relocbase;
99 rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
100 (void *)*where));
101 break;
102
103 case R_TYPE(COPY):
104 /*
105 * These are deferred until all other relocations have
106 * been done. All we do here is make sure that the
107 * COPY relocation is not in a shared library. They
108 * are allowed only in executable files.
109 */
110 if (obj->isdynamic) {
111 _rtld_error(
112 "%s: Unexpected R_COPY relocation in shared library",
113 obj->path);
114 return -1;
115 }
116 rdbg(dodebug, ("COPY (avoid in main)"));
117 break;
118
119 default:
120 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, "
121 "addend = %p, contents = %p, symbol = %s",
122 symnum, (u_long)ELF_R_TYPE(rela->r_info),
123 (void *)rela->r_offset, (void *)rela->r_addend,
124 (void *)*where,
125 obj->strtab + obj->symtab[symnum].st_name));
126 _rtld_error("%s: Unsupported relocation type %ld "
127 "in non-PLT relocations\n",
128 obj->path, (u_long) ELF_R_TYPE(rela->r_info));
129 return -1;
130 }
131 }
132 return 0;
133 }
134
135 int
136 _rtld_relocate_plt_lazy(obj, dodebug)
137 const Obj_Entry *obj;
138 bool dodebug;
139 {
140 const Elf_Rela *rela;
141
142 if (!obj->isdynamic)
143 return 0;
144
145 for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
146 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
147
148 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
149
150 /* Just relocate the GOT slots pointing into the PLT */
151 *where += (Elf_Addr)obj->relocbase;
152 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path,
153 (void *)*where));
154 }
155
156 return 0;
157 }
158
159 int
160 _rtld_relocate_plt_object(obj, rela, addrp, dodebug)
161 const Obj_Entry *obj;
162 const Elf_Rela *rela;
163 caddr_t *addrp;
164 bool dodebug;
165 {
166 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
167 Elf_Addr new_value;
168 const Elf_Sym *def;
169 const Obj_Entry *defobj;
170
171 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
172
173 def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
174 if (def == NULL)
175 return -1;
176
177 new_value = (Elf_Addr)(defobj->relocbase + def->st_value +
178 rela->r_addend);
179 rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p",
180 defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
181 if (*where != new_value)
182 *where = new_value;
183
184 *addrp = (caddr_t)new_value;
185 return 0;
186 }
187