1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
|
/*
* This file is part of the flashrom project.
*
* Copyright (C) 2009,2010 Carl-Daniel Hailfinger
* Copyright (C) 2022 secunet Security Networks AG
* (Written by Thomas Heijligen <thomas.heijligen@secunet.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
/*
* This file implements x86 I/O port permission handling.
*
* For this purpose the platform specific code is encapsuled in two functions
* and compiled only on the respective platform. `platform_get_io_perms()` is
* called to get the permissions and `platform_release_io_perms()` is called for
* releasing those.
*/
#include <errno.h>
#include <string.h>
#include "flash.h"
#include "hwaccess_x86_io.h"
#if defined(__DJGPP__) || defined(__LIBPAYLOAD) /* DJGPP, libpayload */
static int platform_get_io_perms(void)
{
return 0;
}
static int platform_release_io_perms(void *p)
{
return 0;
}
#endif
#if defined(__sun) /* SunOS */
#include <sys/sysi86.h>
static int platform_get_io_perms(void)
{
return sysi86(SI86V86, V86SC_IOPL, PS_IOPL);
}
static int platform_release_io_perms(void *p)
{
sysi86(SI86V86, V86SC_IOPL, 0);
return 0;
}
#endif
#if USE_DEV_IO /* FreeBSD, DragonFlyBSD */
#include <fcntl.h>
#include <unistd.h>
int io_fd;
static int platform_get_io_perms(void)
{
io_fd = open("/dev/io", O_RDWR);
return (io_fd >= 0 ? 0 : -1);
}
static int platform_release_io_perms(void *p)
{
close(io_fd);
return 0;
}
#endif
#if USE_IOPERM /* GNU Hurd */
#include <sys/io.h>
static int platform_get_io_perms(void)
{
return ioperm(0, 65536, 1);
}
static int platform_release_io_perms(void *p)
{
ioperm(0, 65536, 0);
return 0;
}
#endif
#if USE_IOPL /* Linux, Darwin, NetBSD, OpenBSD */
static int platform_get_io_perms(void)
{
return iopl(3);
}
static int platform_release_io_perms(void *p)
{
iopl(0);
return 0;
}
#endif
/**
* @brief Get access to the x86 I/O ports
*
* This function abstracts the platform dependent function to get access to the
* x86 I/O ports and musst be called before using IN[B/W/L] or OUT[B/W/L].
* It registers a shutdown function to release those privileges.
*
* @return 0 on success, platform specific number on failure
*/
int rget_io_perms(void)
{
if (platform_get_io_perms() == 0) {
register_shutdown(platform_release_io_perms, NULL);
return 0;
}
msg_perr("ERROR: Could not get I/O privileges (%s).\n", strerror(errno));
msg_perr("Make sure you are root. If you are root, your kernel may still\n"
"prevent access based on security policies.\n");
msg_perr("On OpenBSD set securelevel=-1 in /etc/rc.securelevel and\n"
"reboot, or reboot into single user mode.\n");
msg_perr("On NetBSD reboot into single user mode or make sure\n"
"that your kernel configuration has the option INSECURE enabled.\n");
return 1;
}
|
