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
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/*
* edd_id - naming of BIOS disk devices via EDD
*
* Copyright (C) 2005 John Hull <John_Hull@Dell.com>
* Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
*
* 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 version 2 of the License.
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE 1
#endif
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
#include <dirent.h>
#include <stdint.h>
#include "../../udev/udev.h"
static void log_fn(struct udev *udev, int priority,
const char *file, int line, const char *fn,
const char *format, va_list args)
{
vsyslog(priority, format, args);
}
int main(int argc, char *argv[])
{
struct udev *udev;
const char *node = NULL;
int i;
int export = 0;
uint32_t disk_id;
uint16_t mbr_valid;
struct dirent *dent;
int disk_fd;
int sysfs_fd;
DIR *dir = NULL;
int rc = 1;
char match[NAME_MAX] = "";
udev = udev_new();
if (udev == NULL)
goto exit;
logging_init("edd_id");
udev_set_log_fn(udev, log_fn);
for (i = 1 ; i < argc; i++) {
char *arg = argv[i];
if (strcmp(arg, "--export") == 0) {
export = 1;
} else
node = arg;
}
if (node == NULL) {
err(udev, "no node specified\n");
fprintf(stderr, "no node specified\n");
goto exit;
}
/* check for kernel support */
dir = opendir("/sys/firmware/edd");
if (dir == NULL) {
info(udev, "no kernel EDD support\n");
fprintf(stderr, "no kernel EDD support\n");
rc = 2;
goto exit;
}
disk_fd = open(node, O_RDONLY);
if (disk_fd < 0) {
info(udev, "unable to open '%s'\n", node);
fprintf(stderr, "unable to open '%s'\n", node);
rc = 3;
goto closedir;
}
/* check for valid MBR signature */
if (lseek(disk_fd, 510, SEEK_SET) < 0) {
info(udev, "seek to MBR validity failed '%s'\n", node);
rc = 4;
goto close;
}
if (read(disk_fd, &mbr_valid, sizeof(mbr_valid)) != sizeof(mbr_valid)) {
info(udev, "read MBR validity failed '%s'\n", node);
rc = 5;
goto close;
}
if (mbr_valid != 0xAA55) {
fprintf(stderr, "no valid MBR signature '%s'\n", node);
info(udev, "no valid MBR signature '%s'\n", node);
rc=6;
goto close;
}
/* read EDD signature */
if (lseek(disk_fd, 440, SEEK_SET) < 0) {
info(udev, "seek to signature failed '%s'\n", node);
rc = 7;
goto close;
}
if (read(disk_fd, &disk_id, sizeof(disk_id)) != sizeof(disk_id)) {
info(udev, "read signature failed '%s'\n", node);
rc = 8;
goto close;
}
/* all zero is invalid */
info(udev, "read id 0x%08x from '%s'\n", disk_id, node);
if (disk_id == 0) {
fprintf(stderr, "no EDD signature '%s'\n", node);
info(udev, "'%s' signature is zero\n", node);
rc = 9;
goto close;
}
/* lookup signature in sysfs to determine the name */
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char file[PATH_SIZE];
char sysfs_id_buf[256];
uint32_t sysfs_id;
ssize_t size;
if (dent->d_name[0] == '.')
continue;
snprintf(file, sizeof(file), "/sys/firmware/edd/%s/mbr_signature", dent->d_name);
file[sizeof(file)-1] = '\0';
sysfs_fd = open(file, O_RDONLY);
if (sysfs_fd < 0) {
info(udev, "unable to open sysfs '%s'\n", file);
continue;
}
size = read(sysfs_fd, sysfs_id_buf, sizeof(sysfs_id_buf)-1);
close(sysfs_fd);
if (size <= 0) {
info(udev, "read sysfs '%s' failed\n", file);
continue;
}
sysfs_id_buf[size] = '\0';
info(udev, "read '%s' from '%s'\n", sysfs_id_buf, file);
sysfs_id = strtoul(sysfs_id_buf, NULL, 16);
/* look for matching value, that appears only once */
if (disk_id == sysfs_id) {
if (match[0] == '\0') {
/* store id */
strlcpy(match, dent->d_name, sizeof(match));
} else {
/* error, same signature for another device */
info(udev, "'%s' does not have a unique signature\n", node);
fprintf(stderr, "'%s' does not have a unique signature\n", node);
rc = 10;
goto exit;
}
}
}
if (match[0] != '\0') {
if (export)
printf("ID_EDD=%s\n", match);
else
printf("%s\n", match);
rc = 0;
}
close:
close(disk_fd);
closedir:
closedir(dir);
exit:
udev_unref(udev);
logging_close();
return rc;
}
|
