mdreloc.c revision 1.6 1 1.1 mycroft #include <sys/types.h>
2 1.1 mycroft #include <sys/stat.h>
3 1.1 mycroft
4 1.1 mycroft #include "debug.h"
5 1.1 mycroft #include "rtld.h"
6 1.1 mycroft
7 1.1 mycroft void
8 1.1 mycroft _rtld_setup_pltgot(const Obj_Entry *obj)
9 1.1 mycroft {
10 1.1 mycroft obj->pltgot[1] = (Elf_Addr) obj;
11 1.1 mycroft obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
12 1.1 mycroft }
13 1.2 mycroft
14 1.2 mycroft int
15 1.3 mycroft _rtld_relocate_nonplt_objects(obj, dodebug)
16 1.2 mycroft Obj_Entry *obj;
17 1.2 mycroft bool dodebug;
18 1.2 mycroft {
19 1.3 mycroft const Elf_Rela *rela;
20 1.2 mycroft
21 1.3 mycroft for (rela = obj->rela; rela < obj->relalim; rela++) {
22 1.3 mycroft Elf_Addr *where;
23 1.3 mycroft const Elf_Sym *def;
24 1.3 mycroft const Obj_Entry *defobj;
25 1.3 mycroft Elf_Addr tmp;
26 1.4 mycroft unsigned long symnum;
27 1.3 mycroft
28 1.3 mycroft where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
29 1.4 mycroft symnum = ELF_R_SYM(rela->r_info);
30 1.3 mycroft
31 1.3 mycroft switch (ELF_R_TYPE(rela->r_info)) {
32 1.3 mycroft case R_TYPE(NONE):
33 1.3 mycroft break;
34 1.2 mycroft
35 1.2 mycroft #if 1 /* XXX should not occur */
36 1.3 mycroft case R_TYPE(GOT32):
37 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
38 1.3 mycroft if (def == NULL)
39 1.3 mycroft return -1;
40 1.3 mycroft
41 1.3 mycroft tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
42 1.3 mycroft rela->r_addend);
43 1.3 mycroft if (*where != tmp)
44 1.3 mycroft *where = tmp;
45 1.3 mycroft rdbg(dodebug, ("GOT32 %s in %s --> %p in %s",
46 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
47 1.5 mycroft obj->path, (void *)*where, defobj->path));
48 1.3 mycroft break;
49 1.3 mycroft
50 1.3 mycroft case R_TYPE(REL32):
51 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
52 1.3 mycroft if (def == NULL)
53 1.3 mycroft return -1;
54 1.3 mycroft
55 1.3 mycroft *where += (Elf_Addr)(defobj->relocbase + def->st_value +
56 1.3 mycroft rela->r_addend) - (Elf_Addr)where;
57 1.3 mycroft rdbg(dodebug, ("PC32 %s in %s --> %p in %s",
58 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
59 1.5 mycroft obj->path, (void *)*where, defobj->path));
60 1.3 mycroft break;
61 1.2 mycroft #endif
62 1.2 mycroft
63 1.3 mycroft case R_TYPE(DIR32):
64 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
65 1.3 mycroft if (def == NULL)
66 1.3 mycroft return -1;
67 1.3 mycroft
68 1.3 mycroft *where += (Elf_Addr)(defobj->relocbase + def->st_value +
69 1.3 mycroft rela->r_addend);
70 1.3 mycroft rdbg(dodebug, ("32 %s in %s --> %p in %s",
71 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
72 1.5 mycroft obj->path, (void *)*where, defobj->path));
73 1.3 mycroft break;
74 1.3 mycroft
75 1.3 mycroft case R_TYPE(GLOB_DAT):
76 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
77 1.3 mycroft if (def == NULL)
78 1.3 mycroft return -1;
79 1.3 mycroft
80 1.3 mycroft tmp = (Elf_Addr)(defobj->relocbase + def->st_value) +
81 1.3 mycroft rela->r_addend;
82 1.3 mycroft if (*where != tmp)
83 1.3 mycroft *where = tmp;
84 1.3 mycroft rdbg(dodebug, ("GLOB_DAT %s in %s --> %p in %s",
85 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
86 1.5 mycroft obj->path, (void *)*where, defobj->path));
87 1.3 mycroft break;
88 1.3 mycroft
89 1.3 mycroft case R_TYPE(RELATIVE):
90 1.3 mycroft if (rela->r_addend)
91 1.3 mycroft *where = (Elf_Addr)obj->relocbase + rela->r_addend;
92 1.3 mycroft else
93 1.3 mycroft *where += (Elf_Addr)obj->relocbase;
94 1.3 mycroft rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
95 1.3 mycroft (void *)*where));
96 1.3 mycroft break;
97 1.3 mycroft
98 1.3 mycroft case R_TYPE(COPY):
99 1.3 mycroft /*
100 1.3 mycroft * These are deferred until all other relocations have
101 1.3 mycroft * been done. All we do here is make sure that the
102 1.3 mycroft * COPY relocation is not in a shared library. They
103 1.3 mycroft * are allowed only in executable files.
104 1.3 mycroft */
105 1.3 mycroft if (!obj->mainprog) {
106 1.3 mycroft _rtld_error(
107 1.2 mycroft "%s: Unexpected R_COPY relocation in shared library",
108 1.3 mycroft obj->path);
109 1.3 mycroft return -1;
110 1.3 mycroft }
111 1.3 mycroft rdbg(dodebug, ("COPY (avoid in main)"));
112 1.3 mycroft break;
113 1.3 mycroft
114 1.3 mycroft default:
115 1.3 mycroft rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, "
116 1.3 mycroft "addend = %p, contents = %p, symbol = %s",
117 1.4 mycroft symnum, (u_long)ELF_R_TYPE(rela->r_info),
118 1.3 mycroft (void *)rela->r_offset, (void *)rela->r_addend,
119 1.3 mycroft (void *)*where,
120 1.4 mycroft obj->strtab + obj->symtab[symnum].st_name));
121 1.3 mycroft _rtld_error("%s: Unsupported relocation type %ld "
122 1.3 mycroft "in non-PLT relocations\n",
123 1.3 mycroft obj->path, (u_long) ELF_R_TYPE(rela->r_info));
124 1.2 mycroft return -1;
125 1.2 mycroft }
126 1.2 mycroft }
127 1.2 mycroft return 0;
128 1.2 mycroft }
129 1.6 mycroft
130 1.6 mycroft int
131 1.6 mycroft _rtld_relocate_plt_lazy(obj, dodebug)
132 1.6 mycroft Obj_Entry *obj;
133 1.6 mycroft bool dodebug;
134 1.6 mycroft {
135 1.6 mycroft const Elf_Rela *rela;
136 1.6 mycroft
137 1.6 mycroft if (obj->mainprog)
138 1.6 mycroft return 0;
139 1.6 mycroft
140 1.6 mycroft for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
141 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
142 1.6 mycroft
143 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
144 1.6 mycroft
145 1.6 mycroft /* Just relocate the GOT slots pointing into the PLT */
146 1.6 mycroft *where += (Elf_Addr)obj->relocbase;
147 1.6 mycroft rdbg(dodebug, ("fixup !main in %s --> %p", obj->path,
148 1.6 mycroft (void *)*where));
149 1.6 mycroft }
150 1.6 mycroft
151 1.6 mycroft return 0;
152 1.6 mycroft }
153 1.6 mycroft
154 1.6 mycroft int
155 1.6 mycroft _rtld_relocate_plt_object(obj, rela, addrp, dodebug)
156 1.6 mycroft Obj_Entry *obj;
157 1.6 mycroft const Elf_Rela *rela;
158 1.6 mycroft caddr_t *addrp;
159 1.6 mycroft bool dodebug;
160 1.6 mycroft {
161 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
162 1.6 mycroft Elf_Addr new_value;
163 1.6 mycroft const Elf_Sym *def;
164 1.6 mycroft const Obj_Entry *defobj;
165 1.6 mycroft
166 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
167 1.6 mycroft
168 1.6 mycroft def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
169 1.6 mycroft if (def == NULL)
170 1.6 mycroft return -1;
171 1.6 mycroft
172 1.6 mycroft new_value = (Elf_Addr)(defobj->relocbase + def->st_value +
173 1.6 mycroft rela->r_addend);
174 1.6 mycroft rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p",
175 1.6 mycroft defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
176 1.6 mycroft if (*where != new_value)
177 1.6 mycroft *where = new_value;
178 1.6 mycroft
179 1.6 mycroft *addrp = (caddr_t)new_value;
180 1.6 mycroft return 0;
181 1.6 mycroft }
182