xref: /dflybsd-src/stand/boot/common/reloc_elf.c (revision 479ab7f0492f2a51b48e8537e4f1dc686fc6014b)
1*479ab7f0SSascha Wildner /*-
2*479ab7f0SSascha Wildner  * Copyright (c) 2003 Jake Burkholder.
3*479ab7f0SSascha Wildner  * Copyright 1996-1998 John D. Polstra.
4*479ab7f0SSascha Wildner  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
5*479ab7f0SSascha Wildner  * Copyright (c) 1998 Peter Wemm <peter@freebsd.org>
6*479ab7f0SSascha Wildner  * All rights reserved.
7*479ab7f0SSascha Wildner  *
8*479ab7f0SSascha Wildner  * Redistribution and use in source and binary forms, with or without
9*479ab7f0SSascha Wildner  * modification, are permitted provided that the following conditions
10*479ab7f0SSascha Wildner  * are met:
11*479ab7f0SSascha Wildner  * 1. Redistributions of source code must retain the above copyright
12*479ab7f0SSascha Wildner  *    notice, this list of conditions and the following disclaimer.
13*479ab7f0SSascha Wildner  * 2. Redistributions in binary form must reproduce the above copyright
14*479ab7f0SSascha Wildner  *    notice, this list of conditions and the following disclaimer in the
15*479ab7f0SSascha Wildner  *    documentation and/or other materials provided with the distribution.
16*479ab7f0SSascha Wildner  *
17*479ab7f0SSascha Wildner  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18*479ab7f0SSascha Wildner  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19*479ab7f0SSascha Wildner  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20*479ab7f0SSascha Wildner  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21*479ab7f0SSascha Wildner  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22*479ab7f0SSascha Wildner  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23*479ab7f0SSascha Wildner  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24*479ab7f0SSascha Wildner  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25*479ab7f0SSascha Wildner  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26*479ab7f0SSascha Wildner  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27*479ab7f0SSascha Wildner  * SUCH DAMAGE.
28*479ab7f0SSascha Wildner  *
29*479ab7f0SSascha Wildner  * $FreeBSD: src/sys/boot/common/reloc_elf.c,v 1.2 2005/12/18 04:52:35 marcel Exp $
30*479ab7f0SSascha Wildner  */
31*479ab7f0SSascha Wildner 
32*479ab7f0SSascha Wildner #include <sys/types.h>
33*479ab7f0SSascha Wildner #include <machine/elf.h>
34*479ab7f0SSascha Wildner 
35*479ab7f0SSascha Wildner #include <errno.h>
36*479ab7f0SSascha Wildner #include <stand.h>
37*479ab7f0SSascha Wildner 
38*479ab7f0SSascha Wildner #define FREEBSD_ELF
39*479ab7f0SSascha Wildner #include <link.h>
40*479ab7f0SSascha Wildner 
41*479ab7f0SSascha Wildner #include "bootstrap.h"
42*479ab7f0SSascha Wildner 
43*479ab7f0SSascha Wildner #define COPYOUT(s,d,l)	archsw.arch_copyout((vm_offset_t)(s), d, l)
44*479ab7f0SSascha Wildner 
45*479ab7f0SSascha Wildner /*
46*479ab7f0SSascha Wildner  * Apply a single intra-module relocation to the data. `relbase' is the
47*479ab7f0SSascha Wildner  * target relocation base for the section (i.e. it corresponds to where
48*479ab7f0SSascha Wildner  * r_offset == 0). `dataaddr' is the relocated address corresponding to
49*479ab7f0SSascha Wildner  * the start of the data, and `len' is the number of bytes.
50*479ab7f0SSascha Wildner  */
51*479ab7f0SSascha Wildner int
__elfN(reloc)52*479ab7f0SSascha Wildner __elfN(reloc)(struct elf_file *ef, symaddr_fn *symaddr, const void *reldata,
53*479ab7f0SSascha Wildner     int reltype, Elf_Addr relbase, Elf_Addr dataaddr, void *data, size_t len)
54*479ab7f0SSascha Wildner {
55*479ab7f0SSascha Wildner #if (defined(__x86_64__) || defined(__i386__)) && __ELF_WORD_SIZE == 64
56*479ab7f0SSascha Wildner 	Elf64_Addr *where, val;
57*479ab7f0SSascha Wildner 	Elf_Addr addend, addr;
58*479ab7f0SSascha Wildner 	Elf_Size rtype, symidx;
59*479ab7f0SSascha Wildner 	const Elf_Rel *rel;
60*479ab7f0SSascha Wildner 	const Elf_Rela *rela;
61*479ab7f0SSascha Wildner 
62*479ab7f0SSascha Wildner 	switch (reltype) {
63*479ab7f0SSascha Wildner 	case ELF_RELOC_REL:
64*479ab7f0SSascha Wildner 		rel = (const Elf_Rel *)reldata;
65*479ab7f0SSascha Wildner 		where = (Elf64_Addr *)((char *)data + relbase + rel->r_offset -
66*479ab7f0SSascha Wildner 		    dataaddr);
67*479ab7f0SSascha Wildner 		addend = 0;
68*479ab7f0SSascha Wildner 		rtype = ELF_R_TYPE(rel->r_info);
69*479ab7f0SSascha Wildner 		symidx = ELF_R_SYM(rel->r_info);
70*479ab7f0SSascha Wildner 		addend = 0;
71*479ab7f0SSascha Wildner 		break;
72*479ab7f0SSascha Wildner 	case ELF_RELOC_RELA:
73*479ab7f0SSascha Wildner 		rela = (const Elf_Rela *)reldata;
74*479ab7f0SSascha Wildner 		where = (Elf64_Addr *)((char *)data + relbase + rela->r_offset -
75*479ab7f0SSascha Wildner 		    dataaddr);
76*479ab7f0SSascha Wildner 		addend = rela->r_addend;
77*479ab7f0SSascha Wildner 		rtype = ELF_R_TYPE(rela->r_info);
78*479ab7f0SSascha Wildner 		symidx = ELF_R_SYM(rela->r_info);
79*479ab7f0SSascha Wildner 		break;
80*479ab7f0SSascha Wildner 	default:
81*479ab7f0SSascha Wildner 		return (EINVAL);
82*479ab7f0SSascha Wildner 	}
83*479ab7f0SSascha Wildner 
84*479ab7f0SSascha Wildner 	if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
85*479ab7f0SSascha Wildner 		return (0);
86*479ab7f0SSascha Wildner 
87*479ab7f0SSascha Wildner 	if (reltype == ELF_RELOC_REL)
88*479ab7f0SSascha Wildner 		addend = *where;
89*479ab7f0SSascha Wildner 
90*479ab7f0SSascha Wildner /* XXX, definitions not available on i386. */
91*479ab7f0SSascha Wildner #define	R_X86_64_64		1
92*479ab7f0SSascha Wildner #define	R_X86_64_RELATIVE	8
93*479ab7f0SSascha Wildner 
94*479ab7f0SSascha Wildner 	switch (rtype) {
95*479ab7f0SSascha Wildner 	case R_X86_64_64:		/* S + A */
96*479ab7f0SSascha Wildner 		addr = symaddr(ef, symidx);
97*479ab7f0SSascha Wildner 		if (addr == 0)
98*479ab7f0SSascha Wildner 			return (ESRCH);
99*479ab7f0SSascha Wildner 		val = addr + addend;
100*479ab7f0SSascha Wildner 		*where = val;
101*479ab7f0SSascha Wildner 		break;
102*479ab7f0SSascha Wildner 	case R_X86_64_RELATIVE:
103*479ab7f0SSascha Wildner 		addr = (Elf_Addr)addend + relbase;
104*479ab7f0SSascha Wildner 		val = addr;
105*479ab7f0SSascha Wildner 		*where = val;
106*479ab7f0SSascha Wildner 		break;
107*479ab7f0SSascha Wildner 	default:
108*479ab7f0SSascha Wildner 		printf("\nunhandled relocation type %u\n", (u_int)rtype);
109*479ab7f0SSascha Wildner 		return (EFTYPE);
110*479ab7f0SSascha Wildner 	}
111*479ab7f0SSascha Wildner 
112*479ab7f0SSascha Wildner 	return (0);
113*479ab7f0SSascha Wildner #elif defined(__i386__) && __ELF_WORD_SIZE == 32
114*479ab7f0SSascha Wildner 	Elf_Addr addend, addr, *where, val;
115*479ab7f0SSascha Wildner 	Elf_Size rtype, symidx;
116*479ab7f0SSascha Wildner 	const Elf_Rel *rel;
117*479ab7f0SSascha Wildner 	const Elf_Rela *rela;
118*479ab7f0SSascha Wildner 
119*479ab7f0SSascha Wildner 	switch (reltype) {
120*479ab7f0SSascha Wildner 	case ELF_RELOC_REL:
121*479ab7f0SSascha Wildner 		rel = (const Elf_Rel *)reldata;
122*479ab7f0SSascha Wildner 		where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
123*479ab7f0SSascha Wildner 		    dataaddr);
124*479ab7f0SSascha Wildner 		addend = 0;
125*479ab7f0SSascha Wildner 		rtype = ELF_R_TYPE(rel->r_info);
126*479ab7f0SSascha Wildner 		symidx = ELF_R_SYM(rel->r_info);
127*479ab7f0SSascha Wildner 		addend = 0;
128*479ab7f0SSascha Wildner 		break;
129*479ab7f0SSascha Wildner 	case ELF_RELOC_RELA:
130*479ab7f0SSascha Wildner 		rela = (const Elf_Rela *)reldata;
131*479ab7f0SSascha Wildner 		where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
132*479ab7f0SSascha Wildner 		    dataaddr);
133*479ab7f0SSascha Wildner 		addend = rela->r_addend;
134*479ab7f0SSascha Wildner 		rtype = ELF_R_TYPE(rela->r_info);
135*479ab7f0SSascha Wildner 		symidx = ELF_R_SYM(rela->r_info);
136*479ab7f0SSascha Wildner 		break;
137*479ab7f0SSascha Wildner 	default:
138*479ab7f0SSascha Wildner 		return (EINVAL);
139*479ab7f0SSascha Wildner 	}
140*479ab7f0SSascha Wildner 
141*479ab7f0SSascha Wildner 	if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
142*479ab7f0SSascha Wildner 		return (0);
143*479ab7f0SSascha Wildner 
144*479ab7f0SSascha Wildner 	if (reltype == ELF_RELOC_REL)
145*479ab7f0SSascha Wildner 		addend = *where;
146*479ab7f0SSascha Wildner 
147*479ab7f0SSascha Wildner /* XXX, definitions not available on x86_64. */
148*479ab7f0SSascha Wildner #define R_386_32	1	/* Add symbol value. */
149*479ab7f0SSascha Wildner #define R_386_GLOB_DAT	6	/* Set GOT entry to data address. */
150*479ab7f0SSascha Wildner #define R_386_RELATIVE	8	/* Add load address of shared object. */
151*479ab7f0SSascha Wildner 
152*479ab7f0SSascha Wildner 	switch (rtype) {
153*479ab7f0SSascha Wildner 	case R_386_RELATIVE:
154*479ab7f0SSascha Wildner 		addr = addend + relbase;
155*479ab7f0SSascha Wildner 		*where = addr;
156*479ab7f0SSascha Wildner 		break;
157*479ab7f0SSascha Wildner 	case R_386_32:		/* S + A */
158*479ab7f0SSascha Wildner 		addr = symaddr(ef, symidx);
159*479ab7f0SSascha Wildner 		if (addr == 0)
160*479ab7f0SSascha Wildner 			return (ESRCH);
161*479ab7f0SSascha Wildner 		val = addr + addend;
162*479ab7f0SSascha Wildner 		*where = val;
163*479ab7f0SSascha Wildner 		break;
164*479ab7f0SSascha Wildner 	default:
165*479ab7f0SSascha Wildner 		printf("\nunhandled relocation type %u\n", (u_int)rtype);
166*479ab7f0SSascha Wildner 		return (EFTYPE);
167*479ab7f0SSascha Wildner 	}
168*479ab7f0SSascha Wildner 
169*479ab7f0SSascha Wildner 	return (0);
170*479ab7f0SSascha Wildner #else
171*479ab7f0SSascha Wildner 	return (EOPNOTSUPP);
172*479ab7f0SSascha Wildner #endif
173*479ab7f0SSascha Wildner }
174