1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright 1996-1998 John D. Polstra.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include "opt_cpu.h"
32
33#include <sys/param.h>
34#include <sys/kernel.h>
35#include <sys/systm.h>
36#include <sys/exec.h>
37#include <sys/imgact.h>
38#include <sys/linker.h>
39#include <sys/proc.h>
40#include <sys/sysent.h>
41#include <sys/imgact_elf.h>
42#include <sys/syscall.h>
43#include <sys/signalvar.h>
44#include <sys/vnode.h>
45
46#include <vm/vm.h>
47#include <vm/pmap.h>
48#include <vm/vm_param.h>
49
50#include <machine/elf.h>
51#include <machine/md_var.h>
52#include <machine/npx.h>
53
54struct sysentvec elf32_freebsd_sysvec = {
55	.sv_size	= SYS_MAXSYSCALL,
56	.sv_table	= sysent,
57	.sv_transtrap	= NULL,
58	.sv_fixup	= __elfN(freebsd_fixup),
59	.sv_sendsig	= sendsig,
60	.sv_sigcode	= sigcode,
61	.sv_szsigcode	= &szsigcode,
62	.sv_name	= "FreeBSD ELF32",
63	.sv_coredump	= __elfN(coredump),
64	.sv_imgact_try	= NULL,
65	.sv_minsigstksz	= MINSIGSTKSZ,
66	.sv_minuser	= VM_MIN_ADDRESS,
67	.sv_maxuser	= VM_MAXUSER_ADDRESS,
68	.sv_usrstack	= USRSTACK,
69	.sv_psstrings	= PS_STRINGS,
70	.sv_stackprot	= VM_PROT_ALL,
71	.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
72	.sv_copyout_strings	= exec_copyout_strings,
73	.sv_setregs	= exec_setregs,
74	.sv_fixlimit	= NULL,
75	.sv_maxssiz	= NULL,
76	.sv_flags	= SV_ABI_FREEBSD | SV_ASLR | SV_IA32 | SV_ILP32 |
77			    SV_SHP | SV_TIMEKEEP | SV_RNG_SEED_VER,
78	.sv_set_syscall_retval = cpu_set_syscall_retval,
79	.sv_fetch_syscall_args = cpu_fetch_syscall_args,
80	.sv_syscallnames = syscallnames,
81	.sv_shared_page_base = SHAREDPAGE,
82	.sv_shared_page_len = PAGE_SIZE,
83	.sv_schedtail	= NULL,
84	.sv_thread_detach = NULL,
85	.sv_trap	= NULL,
86};
87INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec);
88
89static Elf32_Brandinfo freebsd_brand_info = {
90	.brand		= ELFOSABI_FREEBSD,
91	.machine	= EM_386,
92	.compat_3_brand	= "FreeBSD",
93	.emul_path	= NULL,
94	.interp_path	= "/libexec/ld-elf.so.1",
95	.sysvec		= &elf32_freebsd_sysvec,
96	.interp_newpath	= NULL,
97	.brand_note	= &elf32_freebsd_brandnote,
98	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
99};
100
101SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST,
102	(sysinit_cfunc_t) elf32_insert_brand_entry,
103	&freebsd_brand_info);
104
105static Elf32_Brandinfo freebsd_brand_oinfo = {
106	.brand		= ELFOSABI_FREEBSD,
107	.machine	= EM_386,
108	.compat_3_brand	= "FreeBSD",
109	.emul_path	= NULL,
110	.interp_path	= "/usr/libexec/ld-elf.so.1",
111	.sysvec		= &elf32_freebsd_sysvec,
112	.interp_newpath	= NULL,
113	.brand_note	= &elf32_freebsd_brandnote,
114	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE
115};
116
117SYSINIT(oelf32, SI_SUB_EXEC, SI_ORDER_ANY,
118	(sysinit_cfunc_t) elf32_insert_brand_entry,
119	&freebsd_brand_oinfo);
120
121static Elf32_Brandinfo kfreebsd_brand_info = {
122	.brand		= ELFOSABI_FREEBSD,
123	.machine	= EM_386,
124	.compat_3_brand	= "FreeBSD",
125	.emul_path	= NULL,
126	.interp_path	= "/lib/ld.so.1",
127	.sysvec		= &elf32_freebsd_sysvec,
128	.interp_newpath	= NULL,
129	.brand_note	= &elf32_kfreebsd_brandnote,
130	.flags		= BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY
131};
132
133SYSINIT(kelf32, SI_SUB_EXEC, SI_ORDER_ANY,
134	(sysinit_cfunc_t) elf32_insert_brand_entry,
135	&kfreebsd_brand_info);
136
137void
138elf32_dump_thread(struct thread *td, void *dst, size_t *off)
139{
140	void *buf;
141	size_t len;
142
143	len = 0;
144	if (use_xsave) {
145		if (dst != NULL) {
146			npxgetregs(td);
147			len += elf32_populate_note(NT_X86_XSTATE,
148			    get_pcb_user_save_td(td), dst,
149			    cpu_max_ext_state_size, &buf);
150			*(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) =
151			    xsave_mask;
152		} else
153			len += elf32_populate_note(NT_X86_XSTATE, NULL, NULL,
154			    cpu_max_ext_state_size, NULL);
155	}
156	*off = len;
157}
158
159bool
160elf_is_ifunc_reloc(Elf_Size r_info)
161{
162
163	return (ELF_R_TYPE(r_info) == R_386_IRELATIVE);
164}
165
166#define	ERI_LOCAL	0x0001
167
168/* Process one elf relocation with addend. */
169static int
170elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
171    int type, elf_lookup_fn lookup, int flags)
172{
173	Elf_Addr *where;
174	Elf_Addr addr;
175	Elf_Addr addend;
176	Elf_Word rtype, symidx;
177	const Elf_Rel *rel;
178	const Elf_Rela *rela;
179	int error;
180
181	switch (type) {
182	case ELF_RELOC_REL:
183		rel = (const Elf_Rel *)data;
184		where = (Elf_Addr *) (relocbase + rel->r_offset);
185		addend = *where;
186		rtype = ELF_R_TYPE(rel->r_info);
187		symidx = ELF_R_SYM(rel->r_info);
188		break;
189	case ELF_RELOC_RELA:
190		rela = (const Elf_Rela *)data;
191		where = (Elf_Addr *) (relocbase + rela->r_offset);
192		addend = rela->r_addend;
193		rtype = ELF_R_TYPE(rela->r_info);
194		symidx = ELF_R_SYM(rela->r_info);
195		break;
196	default:
197		panic("unknown reloc type %d\n", type);
198	}
199
200	if ((flags & ERI_LOCAL) != 0) {
201		if (rtype == R_386_RELATIVE) {	/* A + B */
202			addr = elf_relocaddr(lf, relocbase + addend);
203			if (*where != addr)
204				*where = addr;
205		}
206		return (0);
207	}
208
209	switch (rtype) {
210		case R_386_NONE:	/* none */
211			break;
212
213		case R_386_32:		/* S + A */
214			error = lookup(lf, symidx, 1, &addr);
215			if (error != 0)
216				return (-1);
217			addr += addend;
218			if (*where != addr)
219				*where = addr;
220			break;
221
222		case R_386_PC32:	/* S + A - P */
223			error = lookup(lf, symidx, 1, &addr);
224			if (error != 0)
225				return (-1);
226			addr += addend - (Elf_Addr)where;
227			if (*where != addr)
228				*where = addr;
229			break;
230
231		case R_386_COPY:	/* none */
232			/*
233			 * There shouldn't be copy relocations in kernel
234			 * objects.
235			 */
236			printf("kldload: unexpected R_COPY relocation, "
237			    "symbol index %d\n", symidx);
238			return (-1);
239			break;
240
241		case R_386_GLOB_DAT:	/* S */
242			error = lookup(lf, symidx, 1, &addr);
243			if (error != 0)
244				return (-1);
245			if (*where != addr)
246				*where = addr;
247			break;
248
249		case R_386_RELATIVE:
250			break;
251
252		case R_386_IRELATIVE:
253			addr = relocbase + addend;
254			addr = ((Elf_Addr (*)(void))addr)();
255			if (*where != addr)
256				*where = addr;
257			break;
258		default:
259			printf("kldload: unexpected relocation type %d, "
260			    "symbol index %d\n", rtype, symidx);
261			return (-1);
262	}
263	return(0);
264}
265
266int
267elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
268    elf_lookup_fn lookup)
269{
270
271	return (elf_reloc_internal(lf, relocbase, data, type, lookup, 0));
272}
273
274int
275elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
276    int type, elf_lookup_fn lookup)
277{
278
279	return (elf_reloc_internal(lf, relocbase, data, type, lookup,
280	    ERI_LOCAL));
281}
282
283int
284elf_cpu_load_file(linker_file_t lf __unused)
285{
286
287	return (0);
288}
289
290int
291elf_cpu_unload_file(linker_file_t lf __unused)
292{
293
294	return (0);
295}
296
297int
298elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused)
299{
300
301	return (0);
302}
303