mdreloc.c revision 1.7 1 #include <sys/types.h>
2 #include <sys/stat.h>
3
4 #include "debug.h"
5 #include "rtld.h"
6
7 void
8 _rtld_setup_pltgot(const Obj_Entry *obj)
9 {
10 obj->pltgot[1] = (Elf_Addr) obj;
11 obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
12 }
13
14 int
15 _rtld_relocate_nonplt_objects(obj, dodebug)
16 const Obj_Entry *obj;
17 bool dodebug;
18 {
19 const Elf_Rela *rela;
20
21 for (rela = obj->rela; rela < obj->relalim; rela++) {
22 Elf_Addr *where;
23 const Elf_Sym *def;
24 const Obj_Entry *defobj;
25 Elf_Addr tmp;
26 unsigned long symnum;
27
28 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
29 symnum = ELF_R_SYM(rela->r_info);
30
31 switch (ELF_R_TYPE(rela->r_info)) {
32 case R_TYPE(NONE):
33 break;
34
35 #if 1 /* XXX should not occur */
36 case R_TYPE(PC32):
37 def = _rtld_find_symdef(symnum, obj, &defobj, false);
38 if (def == NULL)
39 return -1;
40
41 tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
42 rela->r_addend) - (Elf_Addr)where;
43 if (*where != tmp)
44 *where = tmp;
45 rdbg(dodebug, ("PC32 %s in %s --> %p in %s",
46 obj->strtab + obj->symtab[symnum].st_name,
47 obj->path, (void *)*where, defobj->path));
48 break;
49
50 case R_TYPE(GOT32):
51 #endif
52 case R_TYPE(32):
53 case R_TYPE(GLOB_DAT):
54 def = _rtld_find_symdef(symnum, obj, &defobj, false);
55 if (def == NULL)
56 return -1;
57
58 tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
59 rela->r_addend);
60 if (*where != tmp)
61 *where = tmp;
62 rdbg(dodebug, ("32/GLOB_DAT %s in %s --> %p in %s",
63 obj->strtab + obj->symtab[symnum].st_name,
64 obj->path, (void *)*where, defobj->path));
65 break;
66
67 case R_TYPE(RELATIVE):
68 *where += (Elf_Addr)obj->relocbase;
69 rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
70 (void *)*where));
71 break;
72
73 case R_TYPE(COPY):
74 /*
75 * These are deferred until all other relocations have
76 * been done. All we do here is make sure that the
77 * COPY relocation is not in a shared library. They
78 * are allowed only in executable files.
79 */
80 if (!obj->mainprog) {
81 _rtld_error(
82 "%s: Unexpected R_COPY relocation in shared library",
83 obj->path);
84 return -1;
85 }
86 rdbg(dodebug, ("COPY (avoid in main)"));
87 break;
88
89 default:
90 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, "
91 "addend = %p, contents = %p, symbol = %s",
92 symnum, (u_long)ELF_R_TYPE(rela->r_info),
93 (void *)rela->r_offset, (void *)rela->r_addend,
94 (void *)*where,
95 obj->strtab + obj->symtab[symnum].st_name));
96 _rtld_error("%s: Unsupported relocation type %ld "
97 "in non-PLT relocations\n",
98 obj->path, (u_long) ELF_R_TYPE(rela->r_info));
99 return -1;
100 }
101 }
102 return 0;
103 }
104
105 int
106 _rtld_relocate_plt_lazy(obj, dodebug)
107 const Obj_Entry *obj;
108 bool dodebug;
109 {
110 const Elf_Rela *rela;
111
112 if (obj->mainprog)
113 return 0;
114
115 for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
116 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
117
118 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
119
120 /* Just relocate the GOT slots pointing into the PLT */
121 *where += (Elf_Addr)obj->relocbase;
122 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path,
123 (void *)*where));
124 }
125
126 return 0;
127 }
128
129 int
130 _rtld_relocate_plt_object(obj, rela, addrp, dodebug)
131 const Obj_Entry *obj;
132 const Elf_Rela *rela;
133 caddr_t *addrp;
134 bool dodebug;
135 {
136 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
137 Elf_Addr new_value;
138 const Elf_Sym *def;
139 const Obj_Entry *defobj;
140
141 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
142
143 def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
144 if (def == NULL)
145 return -1;
146
147 new_value = (Elf_Addr)(defobj->relocbase + def->st_value);
148 rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p",
149 defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
150 if (*where != new_value)
151 *where = new_value;
152
153 *addrp = (caddr_t)new_value;
154 return 0;
155 }
156