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
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
|
/* $Id: DBGPlugInLinux.cpp $ */
/** @file
* DBGPlugInLinux - Debugger and Guest OS Digger Plugin For Linux.
*/
/*
* Copyright (C) 2008-2013 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#define LOG_GROUP LOG_GROUP_DBGF ///@todo add new log group.
#include "DBGPlugIns.h"
#include "DBGPlugInCommonELF.h"
#include <VBox/vmm/dbgf.h>
#include <iprt/string.h>
#include <iprt/mem.h>
#include <iprt/stream.h>
#include <iprt/ctype.h>
/*******************************************************************************
* Structures and Typedefs *
*******************************************************************************/
/** @name InternalLinux structures
* @{ */
/** @} */
/**
* Linux guest OS digger instance data.
*/
typedef struct DBGDIGGERLINUX
{
/** Whether the information is valid or not.
* (For fending off illegal interface method calls.) */
bool fValid;
/** The address of the linux banner.
* This is set during probing. */
DBGFADDRESS AddrLinuxBanner;
/** Kernel base address.
* This is set during probing. */
DBGFADDRESS AddrKernelBase;
} DBGDIGGERLINUX;
/** Pointer to the linux guest OS digger instance data. */
typedef DBGDIGGERLINUX *PDBGDIGGERLINUX;
/*******************************************************************************
* Defined Constants And Macros *
*******************************************************************************/
/** Validates a 32-bit linux kernel address */
#define LNX32_VALID_ADDRESS(Addr) ((Addr) > UINT32_C(0x80000000) && (Addr) < UINT32_C(0xfffff000))
/** The max kernel size. */
#define LNX_MAX_KERNEL_SIZE 0x0f000000
/*******************************************************************************
* Internal Functions *
*******************************************************************************/
static DECLCALLBACK(int) dbgDiggerLinuxInit(PUVM pUVM, void *pvData);
/*******************************************************************************
* Global Variables *
*******************************************************************************/
/** Table of common linux kernel addresses. */
static uint64_t g_au64LnxKernelAddresses[] =
{
UINT64_C(0xc0100000),
UINT64_C(0x90100000),
UINT64_C(0xffffffff80200000)
};
/**
* @copydoc DBGFOSREG::pfnQueryInterface
*/
static DECLCALLBACK(void *) dbgDiggerLinuxQueryInterface(PUVM pUVM, void *pvData, DBGFOSINTERFACE enmIf)
{
return NULL;
}
/**
* @copydoc DBGFOSREG::pfnQueryVersion
*/
static DECLCALLBACK(int) dbgDiggerLinuxQueryVersion(PUVM pUVM, void *pvData, char *pszVersion, size_t cchVersion)
{
PDBGDIGGERLINUX pThis = (PDBGDIGGERLINUX)pvData;
Assert(pThis->fValid);
/*
* It's all in the linux banner.
*/
int rc = DBGFR3MemReadString(pUVM, 0, &pThis->AddrLinuxBanner, pszVersion, cchVersion);
if (RT_SUCCESS(rc))
{
char *pszEnd = RTStrEnd(pszVersion, cchVersion);
AssertReturn(pszEnd, VERR_BUFFER_OVERFLOW);
while ( pszEnd > pszVersion
&& RT_C_IS_SPACE(pszEnd[-1]))
pszEnd--;
*pszEnd = '\0';
}
else
RTStrPrintf(pszVersion, cchVersion, "DBGFR3MemRead -> %Rrc", rc);
return rc;
}
/**
* @copydoc DBGFOSREG::pfnTerm
*/
static DECLCALLBACK(void) dbgDiggerLinuxTerm(PUVM pUVM, void *pvData)
{
PDBGDIGGERLINUX pThis = (PDBGDIGGERLINUX)pvData;
Assert(pThis->fValid);
pThis->fValid = false;
}
/**
* @copydoc DBGFOSREG::pfnRefresh
*/
static DECLCALLBACK(int) dbgDiggerLinuxRefresh(PUVM pUVM, void *pvData)
{
PDBGDIGGERLINUX pThis = (PDBGDIGGERLINUX)pvData;
NOREF(pThis);
Assert(pThis->fValid);
/*
* For now we'll flush and reload everything.
*/
dbgDiggerLinuxTerm(pUVM, pvData);
return dbgDiggerLinuxInit(pUVM, pvData);
}
/**
* @copydoc DBGFOSREG::pfnInit
*/
static DECLCALLBACK(int) dbgDiggerLinuxInit(PUVM pUVM, void *pvData)
{
PDBGDIGGERLINUX pThis = (PDBGDIGGERLINUX)pvData;
Assert(!pThis->fValid);
#if 0 /* later */
int rc;
/*
* Algorithm to find the ksymtab:
* 1. Find a known export string in kstrtab ("init_task", "enable_hlt" or something).
* 2. Search for the address its at, this should give you the corresponding ksymtab entry.
* 3. Search backwards assuming that kstrtab is corresponding to ksymtab.
*/
DBGFADDRESS AddrKernelKsymTab;
#endif
pThis->fValid = true;
return VINF_SUCCESS;
}
/**
* @copydoc DBGFOSREG::pfnProbe
*/
static DECLCALLBACK(bool) dbgDiggerLinuxProbe(PUVM pUVM, void *pvData)
{
PDBGDIGGERLINUX pThis = (PDBGDIGGERLINUX)pvData;
/*
* Look for "Linux version " at the start of the rodata segment.
* Hope that this comes before any message buffer or other similar string.
* .
* Note! Only Linux version 2.x.y, where x in {0..6}. .
*/
for (unsigned i = 0; i < RT_ELEMENTS(g_au64LnxKernelAddresses); i++)
{
DBGFADDRESS KernelAddr;
DBGFR3AddrFromFlat(pUVM, &KernelAddr, g_au64LnxKernelAddresses[i]);
DBGFADDRESS HitAddr;
static const uint8_t s_abLinuxVersion2x[] = "Linux version 2.";
int rc = DBGFR3MemScan(pUVM, 0, &KernelAddr, LNX_MAX_KERNEL_SIZE, 1,
s_abLinuxVersion2x, sizeof(s_abLinuxVersion2x) - 1, &HitAddr);
if (RT_SUCCESS(rc))
{
char szTmp[128];
char const *pszY = &szTmp[sizeof(s_abLinuxVersion2x) - 1];
rc = DBGFR3MemReadString(pUVM, 0, &HitAddr, szTmp, sizeof(szTmp));
if ( RT_SUCCESS(rc)
&& *pszY >= '0'
&& *pszY <= '6')
{
pThis->AddrKernelBase = KernelAddr;
pThis->AddrLinuxBanner = HitAddr;
return true;
}
}
static const uint8_t s_abLinuxVersion3x[] = "Linux version 3.";
rc = DBGFR3MemScan(pUVM, 0, &KernelAddr, LNX_MAX_KERNEL_SIZE, 1,
s_abLinuxVersion3x, sizeof(s_abLinuxVersion3x) - 1, &HitAddr);
if (RT_SUCCESS(rc))
{
char szTmp[128];
char const *pszY = &szTmp[sizeof(s_abLinuxVersion3x) - 1];
rc = DBGFR3MemReadString(pUVM, 0, &HitAddr, szTmp, sizeof(szTmp));
if ( RT_SUCCESS(rc)
&& *pszY >= '0'
&& *pszY <= '9')
{
pThis->AddrKernelBase = KernelAddr;
pThis->AddrLinuxBanner = HitAddr;
return true;
}
}
}
return false;
}
/**
* @copydoc DBGFOSREG::pfnDestruct
*/
static DECLCALLBACK(void) dbgDiggerLinuxDestruct(PUVM pUVM, void *pvData)
{
}
/**
* @copydoc DBGFOSREG::pfnConstruct
*/
static DECLCALLBACK(int) dbgDiggerLinuxConstruct(PUVM pUVM, void *pvData)
{
return VINF_SUCCESS;
}
const DBGFOSREG g_DBGDiggerLinux =
{
/* .u32Magic = */ DBGFOSREG_MAGIC,
/* .fFlags = */ 0,
/* .cbData = */ sizeof(DBGDIGGERLINUX),
/* .szName = */ "Linux",
/* .pfnConstruct = */ dbgDiggerLinuxConstruct,
/* .pfnDestruct = */ dbgDiggerLinuxDestruct,
/* .pfnProbe = */ dbgDiggerLinuxProbe,
/* .pfnInit = */ dbgDiggerLinuxInit,
/* .pfnRefresh = */ dbgDiggerLinuxRefresh,
/* .pfnTerm = */ dbgDiggerLinuxTerm,
/* .pfnQueryVersion = */ dbgDiggerLinuxQueryVersion,
/* .pfnQueryInterface = */ dbgDiggerLinuxQueryInterface,
/* .u32EndMagic = */ DBGFOSREG_MAGIC
};
|
