mdreloc.c revision 1.9 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 1.9 mycroft _rtld_relocate_nonplt_objects(obj, self, dodebug)
16 1.7 mycroft const Obj_Entry *obj;
17 1.9 mycroft bool self;
18 1.2 mycroft bool dodebug;
19 1.2 mycroft {
20 1.3 mycroft const Elf_Rela *rela;
21 1.2 mycroft
22 1.3 mycroft for (rela = obj->rela; rela < obj->relalim; rela++) {
23 1.3 mycroft Elf_Addr *where;
24 1.3 mycroft const Elf_Sym *def;
25 1.3 mycroft const Obj_Entry *defobj;
26 1.3 mycroft Elf_Addr tmp;
27 1.4 mycroft unsigned long symnum;
28 1.3 mycroft
29 1.3 mycroft where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
30 1.4 mycroft symnum = ELF_R_SYM(rela->r_info);
31 1.3 mycroft
32 1.3 mycroft switch (ELF_R_TYPE(rela->r_info)) {
33 1.3 mycroft case R_TYPE(NONE):
34 1.3 mycroft break;
35 1.3 mycroft
36 1.3 mycroft case R_TYPE(32): /* word32 S + A */
37 1.3 mycroft case R_TYPE(GLOB_DAT): /* word32 S + A */
38 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
39 1.3 mycroft if (def == NULL)
40 1.3 mycroft return -1;
41 1.3 mycroft
42 1.3 mycroft tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
43 1.3 mycroft rela->r_addend);
44 1.3 mycroft
45 1.3 mycroft if (*where != tmp)
46 1.3 mycroft *where = tmp;
47 1.3 mycroft rdbg(dodebug, ("32/GLOB_DAT %s in %s --> %p in %s",
48 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
49 1.5 mycroft obj->path, (void *)*where, defobj->path));
50 1.3 mycroft break;
51 1.3 mycroft
52 1.3 mycroft case R_TYPE(RELATIVE): /* word32 B + A */
53 1.3 mycroft tmp = (Elf_Addr)(obj->relocbase + rela->r_addend);
54 1.3 mycroft if (*where != tmp)
55 1.3 mycroft *where = tmp;
56 1.3 mycroft rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
57 1.3 mycroft (void *)*where));
58 1.3 mycroft break;
59 1.3 mycroft
60 1.3 mycroft case R_TYPE(COPY):
61 1.3 mycroft /*
62 1.3 mycroft * These are deferred until all other relocations have
63 1.3 mycroft * been done. All we do here is make sure that the
64 1.3 mycroft * COPY relocation is not in a shared library. They
65 1.3 mycroft * are allowed only in executable files.
66 1.3 mycroft */
67 1.8 mycroft if (obj->isdynamic) {
68 1.3 mycroft _rtld_error(
69 1.2 mycroft "%s: Unexpected R_COPY relocation in shared library",
70 1.3 mycroft obj->path);
71 1.3 mycroft return -1;
72 1.3 mycroft }
73 1.3 mycroft rdbg(dodebug, ("COPY (avoid in main)"));
74 1.3 mycroft break;
75 1.3 mycroft
76 1.3 mycroft default:
77 1.3 mycroft rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, "
78 1.3 mycroft "addend = %p, contents = %p, symbol = %s",
79 1.4 mycroft symnum, (u_long)ELF_R_TYPE(rela->r_info),
80 1.3 mycroft (void *)rela->r_offset, (void *)rela->r_addend,
81 1.3 mycroft (void *)*where,
82 1.4 mycroft obj->strtab + obj->symtab[symnum].st_name));
83 1.3 mycroft _rtld_error("%s: Unsupported relocation type %ld "
84 1.3 mycroft "in non-PLT relocations\n",
85 1.3 mycroft obj->path, (u_long) ELF_R_TYPE(rela->r_info));
86 1.2 mycroft return -1;
87 1.2 mycroft }
88 1.2 mycroft }
89 1.2 mycroft return 0;
90 1.2 mycroft }
91 1.6 mycroft
92 1.6 mycroft int
93 1.6 mycroft _rtld_relocate_plt_lazy(obj, dodebug)
94 1.7 mycroft const Obj_Entry *obj;
95 1.6 mycroft bool dodebug;
96 1.6 mycroft {
97 1.6 mycroft const Elf_Rela *rela;
98 1.6 mycroft
99 1.8 mycroft if (!obj->isdynamic)
100 1.6 mycroft return 0;
101 1.6 mycroft
102 1.6 mycroft for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
103 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
104 1.6 mycroft
105 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
106 1.6 mycroft
107 1.6 mycroft /* Just relocate the GOT slots pointing into the PLT */
108 1.6 mycroft *where += (Elf_Addr)obj->relocbase;
109 1.6 mycroft rdbg(dodebug, ("fixup !main in %s --> %p", obj->path,
110 1.6 mycroft (void *)*where));
111 1.6 mycroft }
112 1.6 mycroft
113 1.6 mycroft return 0;
114 1.6 mycroft }
115 1.6 mycroft
116 1.6 mycroft int
117 1.6 mycroft _rtld_relocate_plt_object(obj, rela, addrp, dodebug)
118 1.7 mycroft const Obj_Entry *obj;
119 1.6 mycroft const Elf_Rela *rela;
120 1.6 mycroft caddr_t *addrp;
121 1.6 mycroft bool dodebug;
122 1.6 mycroft {
123 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
124 1.6 mycroft Elf_Addr new_value;
125 1.6 mycroft const Elf_Sym *def;
126 1.6 mycroft const Obj_Entry *defobj;
127 1.6 mycroft
128 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
129 1.6 mycroft
130 1.6 mycroft def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
131 1.6 mycroft if (def == NULL)
132 1.6 mycroft return -1;
133 1.6 mycroft
134 1.6 mycroft new_value = (Elf_Addr)(defobj->relocbase + def->st_value +
135 1.6 mycroft rela->r_addend);
136 1.6 mycroft rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p",
137 1.6 mycroft defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
138 1.6 mycroft if (*where != new_value)
139 1.6 mycroft *where = new_value;
140 1.6 mycroft
141 1.6 mycroft *addrp = (caddr_t)(new_value - rela->r_addend);
142 1.6 mycroft return 0;
143 1.6 mycroft }
144