1 /*-
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
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 AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: stable/9/sys/boot/userboot/userboot/elf32_freebsd.c 223695 2011-06-30 16:08:56Z dfr $");
29 
30 #include <sys/param.h>
31 #include <sys/exec.h>
32 #include <sys/linker.h>
33 #include <string.h>
34 #include <i386/include/bootinfo.h>
35 #include <i386/include/elf.h>
36 #include <stand.h>
37 
38 #include "bootstrap.h"
39 #include "libuserboot.h"
40 
41 static int	elf32_exec(struct preloaded_file *amp);
42 static int	elf32_obj_exec(struct preloaded_file *amp);
43 
44 struct file_format i386_elf = { elf32_loadfile, elf32_exec };
45 struct file_format i386_elf_obj = { elf32_obj_loadfile, elf32_obj_exec };
46 
47 /*
48  * There is an ELF kernel and one or more ELF modules loaded.
49  * We wish to start executing the kernel image, so make such
50  * preparations as are required, and do so.
51  */
52 static int
elf32_exec(struct preloaded_file * fp)53 elf32_exec(struct preloaded_file *fp)
54 {
55 	struct file_metadata	*md;
56 	Elf_Ehdr 		*ehdr;
57 	vm_offset_t		entry, bootinfop, modulep, kernend;
58 	int			boothowto, err, bootdev;
59 	uint32_t		stack[1024];
60 
61 
62 	if ((md = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL)
63 		return(EFTYPE);
64 	ehdr = (Elf_Ehdr *)&(md->md_data);
65 
66 	err = bi_load32(fp->f_args, &boothowto, &bootdev, &bootinfop, &modulep, &kernend);
67 	if (err != 0)
68 		return(err);
69 	entry = ehdr->e_entry & 0xffffff;
70 
71 #ifdef DEBUG
72 	printf("Start @ 0x%lx ...\n", entry);
73 #endif
74 
75 	dev_cleanup();
76 
77 	/*
78 	 * Build a scratch stack at physical 0x1000
79 	 */
80 	stack[0] = boothowto;
81 	stack[1] = bootdev;
82 	stack[2] = 0;
83 	stack[3] = 0;
84 	stack[4] = 0;
85 	stack[5] = bootinfop;
86 	stack[6] = modulep;
87 	stack[7] = kernend;
88 	CALLBACK(copyin, stack, 0x1000, sizeof(stack));
89 	CALLBACK(setreg, 4, 0x1000);
90         CALLBACK(exec, entry);
91 
92 	panic("exec returned");
93 }
94 
95 static int
elf32_obj_exec(struct preloaded_file * fp)96 elf32_obj_exec(struct preloaded_file *fp)
97 {
98 	return (EFTYPE);
99 }
100