mdreloc.c revision 1.8 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 1.7 mycroft const 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(PC32):
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) - (Elf_Addr)where;
43 1.3 mycroft if (*where != tmp)
44 1.3 mycroft *where = tmp;
45 1.3 mycroft rdbg(dodebug, ("PC32 %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 1.2 mycroft
50 1.3 mycroft case R_TYPE(GOT32):
51 1.2 mycroft #endif
52 1.3 mycroft case R_TYPE(32):
53 1.3 mycroft case R_TYPE(GLOB_DAT):
54 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
55 1.3 mycroft if (def == NULL)
56 1.3 mycroft return -1;
57 1.3 mycroft
58 1.3 mycroft tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
59 1.3 mycroft rela->r_addend);
60 1.3 mycroft if (*where != tmp)
61 1.3 mycroft *where = tmp;
62 1.3 mycroft rdbg(dodebug, ("32/GLOB_DAT %s in %s --> %p in %s",
63 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
64 1.5 mycroft obj->path, (void *)*where, defobj->path));
65 1.3 mycroft break;
66 1.3 mycroft
67 1.3 mycroft case R_TYPE(RELATIVE):
68 1.3 mycroft *where += (Elf_Addr)obj->relocbase;
69 1.3 mycroft rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
70 1.3 mycroft (void *)*where));
71 1.3 mycroft break;
72 1.3 mycroft
73 1.3 mycroft case R_TYPE(COPY):
74 1.3 mycroft /*
75 1.3 mycroft * These are deferred until all other relocations have
76 1.3 mycroft * been done. All we do here is make sure that the
77 1.3 mycroft * COPY relocation is not in a shared library. They
78 1.3 mycroft * are allowed only in executable files.
79 1.3 mycroft */
80 1.8 mycroft if (obj->isdynamic) {
81 1.3 mycroft _rtld_error(
82 1.2 mycroft "%s: Unexpected R_COPY relocation in shared library",
83 1.3 mycroft obj->path);
84 1.3 mycroft return -1;
85 1.3 mycroft }
86 1.3 mycroft rdbg(dodebug, ("COPY (avoid in main)"));
87 1.3 mycroft break;
88 1.3 mycroft
89 1.3 mycroft default:
90 1.3 mycroft rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, "
91 1.3 mycroft "addend = %p, contents = %p, symbol = %s",
92 1.4 mycroft symnum, (u_long)ELF_R_TYPE(rela->r_info),
93 1.3 mycroft (void *)rela->r_offset, (void *)rela->r_addend,
94 1.3 mycroft (void *)*where,
95 1.4 mycroft obj->strtab + obj->symtab[symnum].st_name));
96 1.3 mycroft _rtld_error("%s: Unsupported relocation type %ld "
97 1.3 mycroft "in non-PLT relocations\n",
98 1.3 mycroft obj->path, (u_long) ELF_R_TYPE(rela->r_info));
99 1.2 mycroft return -1;
100 1.2 mycroft }
101 1.2 mycroft }
102 1.2 mycroft return 0;
103 1.2 mycroft }
104 1.6 mycroft
105 1.6 mycroft int
106 1.6 mycroft _rtld_relocate_plt_lazy(obj, dodebug)
107 1.7 mycroft const Obj_Entry *obj;
108 1.6 mycroft bool dodebug;
109 1.6 mycroft {
110 1.6 mycroft const Elf_Rela *rela;
111 1.6 mycroft
112 1.8 mycroft if (!obj->isdynamic)
113 1.6 mycroft return 0;
114 1.6 mycroft
115 1.6 mycroft for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
116 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
117 1.6 mycroft
118 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
119 1.6 mycroft
120 1.6 mycroft /* Just relocate the GOT slots pointing into the PLT */
121 1.6 mycroft *where += (Elf_Addr)obj->relocbase;
122 1.6 mycroft rdbg(dodebug, ("fixup !main in %s --> %p", obj->path,
123 1.6 mycroft (void *)*where));
124 1.6 mycroft }
125 1.6 mycroft
126 1.6 mycroft return 0;
127 1.6 mycroft }
128 1.6 mycroft
129 1.6 mycroft int
130 1.6 mycroft _rtld_relocate_plt_object(obj, rela, addrp, dodebug)
131 1.7 mycroft const Obj_Entry *obj;
132 1.6 mycroft const Elf_Rela *rela;
133 1.6 mycroft caddr_t *addrp;
134 1.6 mycroft bool dodebug;
135 1.6 mycroft {
136 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
137 1.6 mycroft Elf_Addr new_value;
138 1.6 mycroft const Elf_Sym *def;
139 1.6 mycroft const Obj_Entry *defobj;
140 1.6 mycroft
141 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
142 1.6 mycroft
143 1.6 mycroft def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
144 1.6 mycroft if (def == NULL)
145 1.6 mycroft return -1;
146 1.6 mycroft
147 1.6 mycroft new_value = (Elf_Addr)(defobj->relocbase + def->st_value);
148 1.6 mycroft rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p",
149 1.6 mycroft defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
150 1.6 mycroft if (*where != new_value)
151 1.6 mycroft *where = new_value;
152 1.6 mycroft
153 1.6 mycroft *addrp = (caddr_t)new_value;
154 1.6 mycroft return 0;
155 1.6 mycroft }
156