elf_machdep.c revision 105469
1/*-
2 * Copyright (c) 2001 Jake Burkholder.
3 * Copyright (c) 2000 Eduardo Horvath.
4 * Copyright (c) 1999 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Paul Kranenburg.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *        This product includes software developed by the NetBSD
21 *        Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 *
38 *	from: NetBSD: mdreloc.c,v 1.5 2001/04/25 12:24:51 kleink Exp
39 * $FreeBSD: head/sys/sparc64/sparc64/elf_machdep.c 105469 2002-10-19 19:16:03Z marcel $
40 */
41
42#include <sys/param.h>
43#include <sys/kernel.h>
44#include <sys/systm.h>
45#include <sys/exec.h>
46#include <sys/imgact.h>
47#include <sys/linker.h>
48#include <sys/sysent.h>
49#include <sys/imgact_elf.h>
50#include <sys/syscall.h>
51#include <sys/signalvar.h>
52#include <sys/vnode.h>
53
54#include <vm/vm.h>
55#include <vm/vm_param.h>
56
57#include <machine/elf.h>
58
59#include "linker_if.h"
60
61struct sysentvec elf64_freebsd_sysvec = {
62	SYS_MAXSYSCALL,
63	sysent,
64	0,
65	0,
66	NULL,
67	0,
68	NULL,
69	NULL,
70	__elfN(freebsd_fixup),
71	sendsig,
72	NULL,
73	NULL,
74	NULL,
75	"FreeBSD ELF64",
76	__elfN(coredump),
77	NULL,
78	MINSIGSTKSZ,
79	PAGE_SIZE,
80	VM_MIN_ADDRESS,
81	VM_MAXUSER_ADDRESS,
82	USRSTACK,
83	PS_STRINGS,
84	VM_PROT_READ | VM_PROT_WRITE,
85	exec_copyout_strings,
86	exec_setregs
87};
88
89static Elf64_Brandinfo freebsd_brand_info = {
90						ELFOSABI_FREEBSD,
91						EM_SPARCV9,
92						"FreeBSD",
93						"",
94						"/usr/libexec/ld-elf.so.1",
95						&elf64_freebsd_sysvec
96					  };
97
98SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_ANY,
99	(sysinit_cfunc_t) elf64_insert_brand_entry,
100	&freebsd_brand_info);
101
102/*
103 * The following table holds for each relocation type:
104 *	- the width in bits of the memory location the relocation
105 *	  applies to (not currently used)
106 *	- the number of bits the relocation value must be shifted to the
107 *	  right (i.e. discard least significant bits) to fit into
108 *	  the appropriate field in the instruction word.
109 *	- flags indicating whether
110 *		* the relocation involves a symbol
111 *		* the relocation is relative to the current position
112 *		* the relocation is for a GOT entry
113 *		* the relocation is relative to the load address
114 *
115 */
116#define _RF_S		0x80000000		/* Resolve symbol */
117#define _RF_A		0x40000000		/* Use addend */
118#define _RF_P		0x20000000		/* Location relative */
119#define _RF_G		0x10000000		/* GOT offset */
120#define _RF_B		0x08000000		/* Load address relative */
121#define _RF_U		0x04000000		/* Unaligned */
122#define _RF_SZ(s)	(((s) & 0xff) << 8)	/* memory target size */
123#define _RF_RS(s)	( (s) & 0xff)		/* right shift */
124static int reloc_target_flags[] = {
125	0,							/* NONE */
126	_RF_S|_RF_A|		_RF_SZ(8)  | _RF_RS(0),		/* RELOC_8 */
127	_RF_S|_RF_A|		_RF_SZ(16) | _RF_RS(0),		/* RELOC_16 */
128	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* RELOC_32 */
129	_RF_S|_RF_A|_RF_P|	_RF_SZ(8)  | _RF_RS(0),		/* DISP_8 */
130	_RF_S|_RF_A|_RF_P|	_RF_SZ(16) | _RF_RS(0),		/* DISP_16 */
131	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* DISP_32 */
132	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP_30 */
133	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP_22 */
134	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* HI22 */
135	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 22 */
136	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 13 */
137	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LO10 */
138	_RF_G|			_RF_SZ(32) | _RF_RS(0),		/* GOT10 */
139	_RF_G|			_RF_SZ(32) | _RF_RS(0),		/* GOT13 */
140	_RF_G|			_RF_SZ(32) | _RF_RS(10),	/* GOT22 */
141	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PC10 */
142	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PC22 */
143	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WPLT30 */
144				_RF_SZ(32) | _RF_RS(0),		/* COPY */
145	_RF_S|_RF_A|		_RF_SZ(64) | _RF_RS(0),		/* GLOB_DAT */
146				_RF_SZ(32) | _RF_RS(0),		/* JMP_SLOT */
147	      _RF_A|	_RF_B|	_RF_SZ(64) | _RF_RS(0),		/* RELATIVE */
148	_RF_S|_RF_A|	_RF_U|	_RF_SZ(32) | _RF_RS(0),		/* UA_32 */
149
150	      _RF_A|		_RF_SZ(32) | _RF_RS(0),		/* PLT32 */
151	      _RF_A|		_RF_SZ(32) | _RF_RS(10),	/* HIPLT22 */
152	      _RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LOPLT10 */
153	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PCPLT32 */
154	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PCPLT22 */
155	      _RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(0),		/* PCPLT10 */
156	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 10 */
157	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 11 */
158	_RF_S|_RF_A|		_RF_SZ(64) | _RF_RS(0),		/* 64 */
159	_RF_S|_RF_A|/*extra*/	_RF_SZ(32) | _RF_RS(0),		/* OLO10 */
160	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(42),	/* HH22 */
161	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(32),	/* HM10 */
162	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* LM22 */
163	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(42),	/* PC_HH22 */
164	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(32),	/* PC_HM10 */
165	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(10),	/* PC_LM22 */
166	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP16 */
167	_RF_S|_RF_A|_RF_P|	_RF_SZ(32) | _RF_RS(2),		/* WDISP19 */
168	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* GLOB_JMP */
169	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 7 */
170	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 5 */
171	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* 6 */
172	_RF_S|_RF_A|_RF_P|	_RF_SZ(64) | _RF_RS(0),		/* DISP64 */
173	      _RF_A|		_RF_SZ(64) | _RF_RS(0),		/* PLT64 */
174	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(10),	/* HIX22 */
175	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* LOX10 */
176	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(22),	/* H44 */
177	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(12),	/* M44 */
178	_RF_S|_RF_A|		_RF_SZ(32) | _RF_RS(0),		/* L44 */
179	_RF_S|_RF_A|		_RF_SZ(64) | _RF_RS(0),		/* REGISTER */
180	_RF_S|_RF_A|	_RF_U|	_RF_SZ(64) | _RF_RS(0),		/* UA64 */
181	_RF_S|_RF_A|	_RF_U|	_RF_SZ(16) | _RF_RS(0),		/* UA16 */
182};
183
184#if 0
185static const char *reloc_names[] = {
186	"NONE", "RELOC_8", "RELOC_16", "RELOC_32", "DISP_8",
187	"DISP_16", "DISP_32", "WDISP_30", "WDISP_22", "HI22",
188	"22", "13", "LO10", "GOT10", "GOT13",
189	"GOT22", "PC10", "PC22", "WPLT30", "COPY",
190	"GLOB_DAT", "JMP_SLOT", "RELATIVE", "UA_32", "PLT32",
191	"HIPLT22", "LOPLT10", "LOPLT10", "PCPLT22", "PCPLT32",
192	"10", "11", "64", "OLO10", "HH22",
193	"HM10", "LM22", "PC_HH22", "PC_HM10", "PC_LM22",
194	"WDISP16", "WDISP19", "GLOB_JMP", "7", "5", "6",
195	"DISP64", "PLT64", "HIX22", "LOX10", "H44", "M44",
196	"L44", "REGISTER", "UA64", "UA16"
197};
198#endif
199
200#define RELOC_RESOLVE_SYMBOL(t)		((reloc_target_flags[t] & _RF_S) != 0)
201#define RELOC_PC_RELATIVE(t)		((reloc_target_flags[t] & _RF_P) != 0)
202#define RELOC_BASE_RELATIVE(t)		((reloc_target_flags[t] & _RF_B) != 0)
203#define RELOC_UNALIGNED(t)		((reloc_target_flags[t] & _RF_U) != 0)
204#define RELOC_USE_ADDEND(t)		((reloc_target_flags[t] & _RF_A) != 0)
205#define RELOC_TARGET_SIZE(t)		((reloc_target_flags[t] >> 8) & 0xff)
206#define RELOC_VALUE_RIGHTSHIFT(t)	(reloc_target_flags[t] & 0xff)
207
208static long reloc_target_bitmask[] = {
209#define _BM(x)	(~(-(1ULL << (x))))
210	0,				/* NONE */
211	_BM(8), _BM(16), _BM(32),	/* RELOC_8, _16, _32 */
212	_BM(8), _BM(16), _BM(32),	/* DISP8, DISP16, DISP32 */
213	_BM(30), _BM(22),		/* WDISP30, WDISP22 */
214	_BM(22), _BM(22),		/* HI22, _22 */
215	_BM(13), _BM(10),		/* RELOC_13, _LO10 */
216	_BM(10), _BM(13), _BM(22),	/* GOT10, GOT13, GOT22 */
217	_BM(10), _BM(22),		/* _PC10, _PC22 */
218	_BM(30), 0,			/* _WPLT30, _COPY */
219	_BM(32), _BM(32), _BM(32),	/* _GLOB_DAT, JMP_SLOT, _RELATIVE */
220	_BM(32), _BM(32),		/* _UA32, PLT32 */
221	_BM(22), _BM(10),		/* _HIPLT22, LOPLT10 */
222	_BM(32), _BM(22), _BM(10),	/* _PCPLT32, _PCPLT22, _PCPLT10 */
223	_BM(10), _BM(11), -1,		/* _10, _11, _64 */
224	_BM(10), _BM(22),		/* _OLO10, _HH22 */
225	_BM(10), _BM(22),		/* _HM10, _LM22 */
226	_BM(22), _BM(10), _BM(22),	/* _PC_HH22, _PC_HM10, _PC_LM22 */
227	_BM(16), _BM(19),		/* _WDISP16, _WDISP19 */
228	-1,				/* GLOB_JMP */
229	_BM(7), _BM(5), _BM(6)		/* _7, _5, _6 */
230	-1, -1,				/* DISP64, PLT64 */
231	_BM(22), _BM(13),		/* HIX22, LOX10 */
232	_BM(22), _BM(10), _BM(13),	/* H44, M44, L44 */
233	-1, -1, _BM(16),		/* REGISTER, UA64, UA16 */
234#undef _BM
235};
236#define RELOC_VALUE_BITMASK(t)	(reloc_target_bitmask[t])
237
238/* Process one elf relocation with addend. */
239int
240elf_reloc(linker_file_t lf, const void *data, int type)
241{
242	const Elf_Rela *rela;
243	const Elf_Sym *sym;
244	Elf_Addr relocbase;
245	Elf_Half *where32;
246	Elf_Addr *where;
247	Elf_Word rtype, symidx;
248	Elf_Addr value;
249	Elf_Addr mask;
250	Elf_Addr addr;
251
252	if (type != ELF_RELOC_RELA)
253		return (-1);
254
255	relocbase = (Elf_Addr)lf->address;
256	rela = (const Elf_Rela *)data;
257	where = (Elf_Addr *)(relocbase + rela->r_offset);
258	where32 = (Elf_Half *)where;
259	rtype = ELF_R_TYPE(rela->r_info);
260	symidx = ELF_R_SYM(rela->r_info);
261
262	if (rtype == R_SPARC_NONE)
263		return (0);
264
265	if (rtype == R_SPARC_JMP_SLOT || rtype == R_SPARC_COPY ||
266	    rtype > R_SPARC_UA16)
267		return (-1);
268
269	if (RELOC_UNALIGNED(rtype))
270		return (-1);
271
272	value = rela->r_addend;
273
274	if (RELOC_RESOLVE_SYMBOL(rtype)) {
275		/*
276		 * Work around what appears to be confusion between binutils
277		 * and the v9 ABI.  LO10 and HI22 relocations are listed as
278		 * S + A, but for STB_LOCAL symbols it seems that the value
279		 * in the Elf_Sym refered to by the symbol index is wrong,
280		 * instead the value is in the addend field of the Elf_Rela
281		 * record.  So if the symbol is local don't look it up, just
282		 * use the addend as its value and add in the relocbase.
283		 */
284		sym = elf_get_sym(lf, symidx);
285		if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
286			value += relocbase;
287		else {
288			addr = elf_lookup(lf, symidx, 1);
289			if (addr == 0)
290				return (-1);
291			value += addr;
292		}
293	}
294
295	if (RELOC_PC_RELATIVE(rtype))
296		value -= (Elf_Addr)where;
297
298	if (RELOC_BASE_RELATIVE(rtype))
299		value += relocbase;
300
301	mask = RELOC_VALUE_BITMASK(rtype);
302	value >>= RELOC_VALUE_RIGHTSHIFT(rtype);
303	value &= mask;
304
305	if (RELOC_TARGET_SIZE(rtype) > 32) {
306		*where &= ~mask;
307		*where |= value;
308	} else {
309		*where32 &= ~mask;
310		*where32 |= value;
311	}
312
313	return (0);
314}
315
316int
317elf_cpu_load_file(linker_file_t lf __unused)
318{
319
320	return (0);
321}
322
323int
324elf_cpu_unload_file(linker_file_t lf __unused)
325{
326
327	return (0);
328}
329