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
|
/* init.c - generic EFI initialization and finalization */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2006,2007 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/efi/efi.h>
#include <grub/efi/console.h>
#include <grub/efi/debug.h>
#include <grub/efi/disk.h>
#include <grub/efi/sb.h>
#include <grub/lockdown.h>
#include <grub/term.h>
#include <grub/misc.h>
#include <grub/env.h>
#include <grub/mm.h>
#include <grub/kernel.h>
#include <grub/stack_protector.h>
#ifdef GRUB_STACK_PROTECTOR
static grub_efi_char16_t stack_chk_fail_msg[] =
L"* GRUB: STACK SMASHING DETECTED!!! *\r\n"
L"* GRUB: ABORTED!!! *\r\n"
L"* GRUB: REBOOTING IN 5 SECONDS... *\r\n";
static grub_guid_t rng_protocol_guid = GRUB_EFI_RNG_PROTOCOL_GUID;
/*
* Don't put this on grub_efi_init()'s local stack to avoid it
* getting a stack check.
*/
static grub_efi_uint8_t stack_chk_guard_buf[32];
/* Initialize canary in case there is no RNG protocol. */
grub_addr_t __stack_chk_guard = (grub_addr_t) GRUB_STACK_PROTECTOR_INIT;
void __attribute__ ((noreturn))
__stack_chk_fail (void)
{
grub_efi_simple_text_output_interface_t *o;
/*
* Use ConOut here rather than StdErr. StdErr only goes to
* the serial console, at least on EDK2.
*/
o = grub_efi_system_table->con_out;
o->output_string (o, stack_chk_fail_msg);
grub_efi_system_table->boot_services->stall (5000000);
grub_efi_system_table->runtime_services->reset_system (GRUB_EFI_RESET_SHUTDOWN,
GRUB_EFI_ABORTED, 0, NULL);
/*
* We shouldn't get here. It's unsafe to return because the stack
* is compromised and this function is noreturn, so just busy
* loop forever.
*/
do
{
/* Do not optimize out the loop. */
asm volatile ("");
}
while (1);
}
static void
stack_protector_init (void)
{
grub_efi_rng_protocol_t *rng;
/* Set up the stack canary. Make errors here non-fatal for now. */
rng = grub_efi_locate_protocol (&rng_protocol_guid, NULL);
if (rng != NULL)
{
grub_efi_status_t status;
status = rng->get_rng (rng, NULL, sizeof (stack_chk_guard_buf),
stack_chk_guard_buf);
if (status == GRUB_EFI_SUCCESS)
grub_memcpy (&__stack_chk_guard, stack_chk_guard_buf, sizeof (__stack_chk_guard));
}
}
#else
static void
stack_protector_init (void)
{
}
#endif
grub_addr_t grub_modbase;
__attribute__ ((__optimize__ ("-fno-stack-protector"))) void
grub_efi_init (void)
{
grub_modbase = grub_efi_section_addr ("mods");
/* First of all, initialize the console so that GRUB can display
messages. */
grub_console_init ();
stack_protector_init ();
/* Initialize the memory management system. */
grub_efi_mm_init ();
/*
* Lockdown the GRUB and register the shim_lock verifier
* if the UEFI Secure Boot is enabled.
*/
if (grub_efi_get_secureboot () == GRUB_EFI_SECUREBOOT_MODE_ENABLED)
{
grub_lockdown ();
grub_shim_lock_verifier_setup ();
}
grub_efi_system_table->boot_services->set_watchdog_timer (0, 0, 0, NULL);
grub_efidisk_init ();
grub_efi_register_debug_commands ();
}
void (*grub_efi_net_config) (grub_efi_handle_t hnd,
char **device,
char **path);
void
grub_machine_get_bootlocation (char **device, char **path)
{
grub_efi_loaded_image_t *image = NULL;
char *p;
image = grub_efi_get_loaded_image (grub_efi_image_handle);
if (!image)
return;
*device = grub_efidisk_get_device_name (image->device_handle);
if (!*device && grub_efi_net_config)
{
grub_efi_net_config (image->device_handle, device, path);
return;
}
*path = grub_efi_get_filename (image->file_path);
if (*path)
{
/* Get the directory. */
p = grub_strrchr (*path, '/');
if (p)
*p = '\0';
}
}
void
grub_efi_fini (void)
{
grub_efidisk_fini ();
grub_console_fini ();
}
|
