mdreloc.c revision 1.14 1 1.14 mycroft /* $NetBSD: mdreloc.c,v 1.14 2002/09/25 07:27:52 mycroft Exp $ */
2 1.10 junyoung
3 1.1 mycroft #include <sys/types.h>
4 1.1 mycroft #include <sys/stat.h>
5 1.1 mycroft
6 1.1 mycroft #include "debug.h"
7 1.1 mycroft #include "rtld.h"
8 1.1 mycroft
9 1.12 mycroft void _rtld_bind_start(void);
10 1.11 mycroft void _rtld_relocate_nonplt_self(Elf_Dyn *, Elf_Addr);
11 1.14 mycroft caddr_t _rtld_bind __P((const Obj_Entry *, Elf_Word));
12 1.11 mycroft
13 1.1 mycroft void
14 1.1 mycroft _rtld_setup_pltgot(const Obj_Entry *obj)
15 1.1 mycroft {
16 1.1 mycroft obj->pltgot[1] = (Elf_Addr) obj;
17 1.1 mycroft obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
18 1.1 mycroft }
19 1.2 mycroft
20 1.11 mycroft void
21 1.11 mycroft _rtld_relocate_nonplt_self(dynp, relocbase)
22 1.11 mycroft Elf_Dyn *dynp;
23 1.11 mycroft Elf_Addr relocbase;
24 1.11 mycroft {
25 1.11 mycroft const Elf_Rela *rela = 0, *relalim;
26 1.11 mycroft Elf_Addr relasz = 0;
27 1.11 mycroft Elf_Addr *where;
28 1.11 mycroft
29 1.11 mycroft for (; dynp->d_tag != DT_NULL; dynp++) {
30 1.11 mycroft switch (dynp->d_tag) {
31 1.11 mycroft case DT_RELA:
32 1.11 mycroft rela = (const Elf_Rela *)(relocbase + dynp->d_un.d_ptr);
33 1.11 mycroft break;
34 1.11 mycroft case DT_RELASZ:
35 1.11 mycroft relasz = dynp->d_un.d_val;
36 1.11 mycroft break;
37 1.11 mycroft }
38 1.11 mycroft }
39 1.11 mycroft relalim = (const Elf_Rela *)((caddr_t)rela + relasz);
40 1.11 mycroft for (; rela < relalim; rela++) {
41 1.11 mycroft where = (Elf_Addr *)(relocbase + rela->r_offset);
42 1.11 mycroft *where += (Elf_Addr)relocbase;
43 1.11 mycroft }
44 1.11 mycroft }
45 1.11 mycroft
46 1.2 mycroft int
47 1.13 mycroft _rtld_relocate_nonplt_objects(obj, self)
48 1.7 mycroft const Obj_Entry *obj;
49 1.9 mycroft bool self;
50 1.2 mycroft {
51 1.3 mycroft const Elf_Rela *rela;
52 1.11 mycroft
53 1.11 mycroft if (self)
54 1.11 mycroft return 0;
55 1.2 mycroft
56 1.3 mycroft for (rela = obj->rela; rela < obj->relalim; rela++) {
57 1.3 mycroft Elf_Addr *where;
58 1.3 mycroft const Elf_Sym *def;
59 1.3 mycroft const Obj_Entry *defobj;
60 1.3 mycroft Elf_Addr tmp;
61 1.4 mycroft unsigned long symnum;
62 1.3 mycroft
63 1.3 mycroft where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
64 1.4 mycroft symnum = ELF_R_SYM(rela->r_info);
65 1.3 mycroft
66 1.3 mycroft switch (ELF_R_TYPE(rela->r_info)) {
67 1.3 mycroft case R_TYPE(NONE):
68 1.3 mycroft break;
69 1.2 mycroft
70 1.2 mycroft #if 1 /* XXX should not occur */
71 1.3 mycroft case R_TYPE(PC32):
72 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
73 1.3 mycroft if (def == NULL)
74 1.3 mycroft return -1;
75 1.3 mycroft
76 1.3 mycroft tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
77 1.3 mycroft rela->r_addend) - (Elf_Addr)where;
78 1.3 mycroft if (*where != tmp)
79 1.3 mycroft *where = tmp;
80 1.13 mycroft rdbg(("PC32 %s in %s --> %p in %s",
81 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
82 1.5 mycroft obj->path, (void *)*where, defobj->path));
83 1.3 mycroft break;
84 1.2 mycroft
85 1.3 mycroft case R_TYPE(GOT32):
86 1.2 mycroft #endif
87 1.3 mycroft case R_TYPE(32):
88 1.3 mycroft case R_TYPE(GLOB_DAT):
89 1.4 mycroft def = _rtld_find_symdef(symnum, obj, &defobj, false);
90 1.3 mycroft if (def == NULL)
91 1.3 mycroft return -1;
92 1.3 mycroft
93 1.3 mycroft tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
94 1.3 mycroft rela->r_addend);
95 1.3 mycroft if (*where != tmp)
96 1.3 mycroft *where = tmp;
97 1.13 mycroft rdbg(("32/GLOB_DAT %s in %s --> %p in %s",
98 1.5 mycroft obj->strtab + obj->symtab[symnum].st_name,
99 1.5 mycroft obj->path, (void *)*where, defobj->path));
100 1.3 mycroft break;
101 1.3 mycroft
102 1.3 mycroft case R_TYPE(RELATIVE):
103 1.3 mycroft *where += (Elf_Addr)obj->relocbase;
104 1.13 mycroft rdbg(("RELATIVE in %s --> %p", obj->path,
105 1.3 mycroft (void *)*where));
106 1.3 mycroft break;
107 1.3 mycroft
108 1.3 mycroft case R_TYPE(COPY):
109 1.3 mycroft /*
110 1.3 mycroft * These are deferred until all other relocations have
111 1.3 mycroft * been done. All we do here is make sure that the
112 1.3 mycroft * COPY relocation is not in a shared library. They
113 1.3 mycroft * are allowed only in executable files.
114 1.3 mycroft */
115 1.8 mycroft if (obj->isdynamic) {
116 1.3 mycroft _rtld_error(
117 1.2 mycroft "%s: Unexpected R_COPY relocation in shared library",
118 1.3 mycroft obj->path);
119 1.3 mycroft return -1;
120 1.3 mycroft }
121 1.13 mycroft rdbg(("COPY (avoid in main)"));
122 1.3 mycroft break;
123 1.3 mycroft
124 1.3 mycroft default:
125 1.13 mycroft rdbg(("sym = %lu, type = %lu, offset = %p, "
126 1.3 mycroft "addend = %p, contents = %p, symbol = %s",
127 1.4 mycroft symnum, (u_long)ELF_R_TYPE(rela->r_info),
128 1.3 mycroft (void *)rela->r_offset, (void *)rela->r_addend,
129 1.3 mycroft (void *)*where,
130 1.4 mycroft obj->strtab + obj->symtab[symnum].st_name));
131 1.3 mycroft _rtld_error("%s: Unsupported relocation type %ld "
132 1.3 mycroft "in non-PLT relocations\n",
133 1.3 mycroft obj->path, (u_long) ELF_R_TYPE(rela->r_info));
134 1.2 mycroft return -1;
135 1.2 mycroft }
136 1.2 mycroft }
137 1.2 mycroft return 0;
138 1.2 mycroft }
139 1.6 mycroft
140 1.6 mycroft int
141 1.13 mycroft _rtld_relocate_plt_lazy(obj)
142 1.7 mycroft const Obj_Entry *obj;
143 1.6 mycroft {
144 1.6 mycroft const Elf_Rela *rela;
145 1.6 mycroft
146 1.8 mycroft if (!obj->isdynamic)
147 1.6 mycroft return 0;
148 1.6 mycroft
149 1.6 mycroft for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
150 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
151 1.6 mycroft
152 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
153 1.6 mycroft
154 1.6 mycroft /* Just relocate the GOT slots pointing into the PLT */
155 1.6 mycroft *where += (Elf_Addr)obj->relocbase;
156 1.13 mycroft rdbg(("fixup !main in %s --> %p", obj->path, (void *)*where));
157 1.6 mycroft }
158 1.6 mycroft
159 1.6 mycroft return 0;
160 1.6 mycroft }
161 1.6 mycroft
162 1.14 mycroft caddr_t
163 1.14 mycroft _rtld_bind(obj, reloff)
164 1.7 mycroft const Obj_Entry *obj;
165 1.14 mycroft Elf_Word reloff;
166 1.6 mycroft {
167 1.14 mycroft const Elf_Rela *rela = (const Elf_Rela *)((caddr_t)obj->pltrela + reloff);
168 1.6 mycroft Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
169 1.6 mycroft Elf_Addr new_value;
170 1.6 mycroft const Elf_Sym *def;
171 1.6 mycroft const Obj_Entry *defobj;
172 1.6 mycroft
173 1.6 mycroft assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
174 1.6 mycroft
175 1.6 mycroft def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
176 1.6 mycroft if (def == NULL)
177 1.14 mycroft _rtld_die();
178 1.6 mycroft
179 1.6 mycroft new_value = (Elf_Addr)(defobj->relocbase + def->st_value);
180 1.13 mycroft rdbg(("bind now/fixup in %s --> old=%p new=%p",
181 1.6 mycroft defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
182 1.6 mycroft if (*where != new_value)
183 1.6 mycroft *where = new_value;
184 1.6 mycroft
185 1.14 mycroft return (caddr_t)new_value;
186 1.6 mycroft }
187