1 /*-
2 * Copyright 1996-1998 John D. Polstra.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: src/sys/i386/i386/elf_machdep.c,v 1.8 1999/12/21 11:14:02 eivind Exp $
26 */
27
28 #include <sys/param.h>
29 #include <sys/kernel.h>
30 #include <sys/systm.h>
31 #include <sys/linker.h>
32 #include <sys/sysent.h>
33 #include <sys/imgact_elf.h>
34 #include <sys/syscall.h>
35 #include <sys/signalvar.h>
36 #include <sys/vnode.h>
37 #include <machine/elf.h>
38 #include <machine/md_var.h>
39
40 static struct sysentvec elf64_dragonfly_sysvec = {
41 .sv_size = SYS_MAXSYSCALL,
42 .sv_table = sysent,
43 .sv_sigsize = 0,
44 .sv_sigtbl = NULL,
45 .sv_errsize = 0,
46 .sv_errtbl = NULL,
47 .sv_transtrap = NULL,
48 .sv_fixup = __elfN(dragonfly_fixup),
49 .sv_sendsig = sendsig,
50 .sv_sigcode = sigcode,
51 .sv_szsigcode = &szsigcode,
52 .sv_name = "DragonFly ELF64",
53 .sv_coredump = __elfN(coredump),
54 .sv_imgact_try = NULL,
55 .sv_minsigstksz = MINSIGSTKSZ,
56 };
57
58 static Elf64_Brandinfo dragonfly_brand_info = {
59 .brand = ELFOSABI_NONE,
60 .machine = EM_X86_64,
61 .compat_3_brand = "DragonFly",
62 .emul_path = NULL,
63 .interp_path = "/libexec/ld-elf.so.2",
64 .sysvec = &elf64_dragonfly_sysvec,
65 .interp_newpath = NULL,
66 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE,
67 .brand_note = &elf64_dragonfly_brandnote,
68 };
69
70 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST,
71 (sysinit_cfunc_t) elf64_insert_brand_entry,
72 &dragonfly_brand_info);
73
74 /* Process one elf relocation with addend. */
75 static int
elf_reloc_internal(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,int local,elf_lookup_fn lookup)76 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
77 int type, int local, elf_lookup_fn lookup)
78 {
79 Elf64_Addr *where, val;
80 Elf32_Addr *where32, val32;
81 Elf_Addr addr;
82 Elf_Addr addend;
83 Elf_Size rtype, symidx;
84 const Elf_Rel *rel;
85 const Elf_Rela *rela;
86
87 switch (type) {
88 case ELF_RELOC_REL:
89 rel = (const Elf_Rel *)data;
90 where = (Elf_Addr *) (relocbase + rel->r_offset);
91 rtype = ELF_R_TYPE(rel->r_info);
92 symidx = ELF_R_SYM(rel->r_info);
93 /* Addend is 32 bit on 32 bit relocs */
94 switch (rtype) {
95 case R_X86_64_PC32:
96 case R_X86_64_PLT32:
97 case R_X86_64_32:
98 case R_X86_64_32S:
99 addend = *(Elf32_Addr *)where;
100 break;
101 default:
102 addend = *where;
103 break;
104 }
105 break;
106 case ELF_RELOC_RELA:
107 rela = (const Elf_Rela *)data;
108 where = (Elf_Addr *) (relocbase + rela->r_offset);
109 addend = rela->r_addend;
110 rtype = ELF_R_TYPE(rela->r_info);
111 symidx = ELF_R_SYM(rela->r_info);
112 break;
113 default:
114 panic("unknown reloc type %d", type);
115 }
116
117 switch (rtype) {
118
119 case R_X86_64_NONE: /* none */
120 break;
121
122 case R_X86_64_64: /* S + A */
123 if (lookup(lf, symidx, 1, &addr))
124 return -1;
125 val = addr + addend;
126 if (*where != val)
127 *where = val;
128 break;
129
130 case R_X86_64_PC32: /* S + A - P */
131 case R_X86_64_PLT32: /* XXX assume PLT as S too */
132 if (lookup(lf, symidx, 1, &addr))
133 return -1;
134 where32 = (Elf32_Addr *)where;
135 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
136 if (*where32 != val32)
137 *where32 = val32;
138 break;
139
140 case R_X86_64_32: /* S + A zero extend */
141 case R_X86_64_32S: /* S + A sign extend */
142 if (lookup(lf, symidx, 1, &addr))
143 return -1;
144 val32 = (Elf32_Addr)(addr + addend);
145 where32 = (Elf32_Addr *)where;
146 if (*where32 != val32)
147 *where32 = val32;
148 break;
149
150 case R_X86_64_COPY: /* none */
151 /*
152 * There shouldn't be copy relocations in kernel
153 * objects.
154 */
155 kprintf("kldload: unexpected R_COPY relocation\n");
156 return -1;
157 break;
158
159 case R_X86_64_GLOB_DAT: /* S */
160 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */
161 if (lookup(lf, symidx, 1, &addr))
162 return -1;
163 if (*where != addr)
164 *where = addr;
165 break;
166
167 case R_X86_64_RELATIVE: /* B + A */
168 addr = relocbase + addend;
169 val = addr;
170 if (*where != val)
171 *where = val;
172 break;
173
174 default:
175 kprintf("kldload: unexpected relocation type %ld\n",
176 rtype);
177 return -1;
178 }
179 return(0);
180 }
181
182 int
elf_reloc(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,elf_lookup_fn lookup)183 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
184 elf_lookup_fn lookup)
185 {
186
187 return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
188 }
189
190 int
elf_reloc_local(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,elf_lookup_fn lookup)191 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
192 int type, elf_lookup_fn lookup)
193 {
194
195 return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
196 }
197