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
|
/* ----------------------------------------------------------------------- *
*
* Copyright 2008 H. Peter Anvin - All Rights Reserved
*
* 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, Inc., 51 Franklin St, Fifth Floor,
* Boston MA 02110-1301, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* sanboot.c
*
* Invoke the gPXE "sanboot" command, if available.
*/
#include <alloca.h>
#include <inttypes.h>
#include <stdio.h>
#include <console.h>
#include <com32.h>
#include <stdbool.h>
#include <string.h>
#include <syslinux/config.h>
struct segoff16 {
uint16_t offs, seg;
};
struct s_PXENV_FILE_CHECK_API {
uint16_t Status;
uint16_t Size;
uint32_t Magic;
uint32_t Provider;
uint32_t APIMask;
uint32_t Flags;
};
static bool is_gpxe(void)
{
const struct syslinux_version *sv;
com32sys_t reg;
struct s_PXENV_FILE_CHECK_API *fca;
sv = syslinux_version();
if (sv->filesystem != SYSLINUX_FS_PXELINUX)
return false; /* Not PXELINUX */
fca = __com32.cs_bounce;
memset(fca, 0, sizeof *fca);
fca->Size = sizeof *fca;
fca->Magic = 0x91d447b2;
memset(®, 0, sizeof reg);
reg.eax.w[0] = 0x0009;
reg.ebx.w[0] = 0x00e6; /* PXENV_FILE_API_CHECK */
reg.edi.w[0] = OFFS(fca);
reg.es = SEG(fca);
__intcall(0x22, ®, ®);
if (reg.eflags.l & EFLAGS_CF)
return false; /* Cannot invoke PXE stack */
if (reg.eax.w[0] || fca->Status)
return false; /* PXE failure */
if (fca->Magic != 0xe9c17b20)
return false; /* Incorrect magic */
if (fca->Size < sizeof *fca)
return false; /* Short return */
if (!(fca->APIMask & (1 << 5)))
return false; /* No FILE EXEC */
return true;
}
struct s_PXENV_FILE_EXEC {
uint16_t Status;
struct segoff16 Command;
};
static void sanboot(const char **args)
{
char *q;
struct s_PXENV_FILE_EXEC *fx;
com32sys_t reg;
memset(®, 0, sizeof reg);
fx = __com32.cs_bounce;
q = (char *)(fx+1);
fx->Status = 1;
fx->Command.offs = OFFS(q);
fx->Command.seg = SEG(q);
q = stpcpy(q, "sanboot");
while (*args) {
*q++ = ' ';
q = stpcpy(q, *args);
args++;
}
memset(®, 0, sizeof reg);
reg.eax.w[0] = 0x0009;
reg.ebx.w[0] = 0x00e5; /* PXENV_FILE_EXEC */
reg.edi.w[0] = OFFS(fx);
reg.es = SEG(fx);
__intcall(0x22, ®, ®);
/* This should not return... */
}
int main(int argc, const char *argv[])
{
openconsole(&dev_null_r, &dev_stdcon_w);
if (argc < 2) {
printf("Usage: sanboot rootpath\n");
return 1;
}
if (!is_gpxe()) {
printf("sanboot: gPXE API not detected\n");
return 1;
}
sanboot(argv+1);
/* sanboot() should not return... */
printf("SAN boot failed.\n");
return 1;
}
|
