summaryrefslogtreecommitdiff
path: root/plugins/PluginUpdater/src/checksum.cpp
blob: 217bdb579fd7178c51bc37ca51e531e8a66617af (plain)
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

// Checksum Tool
// By Bio (C) 2012

#include "stdafx.h"

// Return codes
#define RESULT_OK			0
#define RESULT_NOTFOUND		10
#define RESULT_READERROR	20
#define RESULT_NOTPE		30
#define RESULT_CORRUPTED	40
#define RESULT_INVALID		50
#define RESULT_NONE			100

#define DEBUG_SECTIONS		1
#define DEBUG_REALLOCS		1

int debug = 0;

#pragma comment(lib, "version.lib")

struct MFileMapping
{
	uint8_t *ptr;
	HANDLE hMap, hFile;

	MFileMapping(const wchar_t *pwszFileName)
	{
		ptr = nullptr;
		hMap = nullptr;

		hFile = CreateFile(pwszFileName, GENERIC_READ, FILE_SHARE_READ, nullptr, OPEN_EXISTING, 0, nullptr);
		if (hFile != INVALID_HANDLE_VALUE)
			hMap = CreateFileMapping(hFile, nullptr, PAGE_WRITECOPY, 0, 0, nullptr);
		if (hMap)
			ptr = (uint8_t*)MapViewOfFile(hMap, FILE_MAP_COPY, 0, 0, 0);
	}

	~MFileMapping()
	{
		if (ptr)
			UnmapViewOfFile(ptr);

		if (hMap)
			CloseHandle(hMap);

		if (hFile != INVALID_HANDLE_VALUE)
			CloseHandle(hFile);
	}
};

static void PatchResourcesDirectory(PIMAGE_RESOURCE_DIRECTORY pIRD, uint8_t *pBase);

static void PatchResourceEntry(PIMAGE_RESOURCE_DIRECTORY_ENTRY pIRDE, uint8_t *pBase)
{
	if (pIRDE->DataIsDirectory)
		PatchResourcesDirectory(PIMAGE_RESOURCE_DIRECTORY(pBase + pIRDE->OffsetToDirectory), pBase);
}

static void PatchResourcesDirectory(PIMAGE_RESOURCE_DIRECTORY pIRD, uint8_t *pBase)
{
	UINT i;
	pIRD->TimeDateStamp = 0;

	PIMAGE_RESOURCE_DIRECTORY_ENTRY pIRDE = PIMAGE_RESOURCE_DIRECTORY_ENTRY(pIRD + 1);
	for (i = 0; i < pIRD->NumberOfNamedEntries; i++, pIRDE++)
		PatchResourceEntry(pIRDE, pBase);

	for (i = 0; i < pIRD->NumberOfIdEntries; i++, pIRDE++)
		PatchResourceEntry(pIRDE, pBase);
}

__forceinline bool Contains(PIMAGE_SECTION_HEADER pISH, uint32_t address, uint32_t size = 0)
{
	return (address >= pISH->VirtualAddress && address + size <= pISH->VirtualAddress + pISH->SizeOfRawData);
}

int CalculateModuleHash(const wchar_t *filename, char *szDest)
{
	MFileMapping map(filename);
	if (map.hFile == INVALID_HANDLE_VALUE)
		return RESULT_NOTFOUND;

	if (map.ptr == nullptr)
		return RESULT_READERROR;

	// check minimum and maximum size
	DWORD hsize = 0, filesize = GetFileSize(map.hFile, &hsize);
	if (!filesize || filesize == INVALID_FILE_SIZE || hsize)
		return RESULT_INVALID;

	if (filesize < sizeof(IMAGE_DOS_HEADER) + sizeof(IMAGE_NT_HEADERS))
		return RESULT_NOTPE;

	mir_md5_state_t pms;
	mir_md5_init(&pms);

	PIMAGE_DOS_HEADER pIDH = (PIMAGE_DOS_HEADER)map.ptr;
	if (pIDH->e_magic != IMAGE_DOS_SIGNATURE) {
LBL_NotPE:
		mir_md5_append(&pms, map.ptr, filesize);
	}
	else {
		PIMAGE_NT_HEADERS pINTH = (PIMAGE_NT_HEADERS)(map.ptr + pIDH->e_lfanew);
		if ((uint8_t*)pINTH + sizeof(IMAGE_NT_HEADERS) >= map.ptr + filesize)
			return RESULT_CORRUPTED;
		
		if (pINTH->Signature != IMAGE_NT_SIGNATURE)
			goto LBL_NotPE;

		uint16_t  machine = pINTH->FileHeader.Machine;
		uint32_t sections = pINTH->FileHeader.NumberOfSections;
		if (!sections)
			return RESULT_INVALID;

		PIMAGE_DATA_DIRECTORY pIDD = nullptr;
		PIMAGE_DEBUG_DIRECTORY pDBG = nullptr;
		uint8_t *pRealloc = nullptr;
		ULONGLONG base = 0;

		// try to found correct offset independent of architectures
		uint32_t offset = pIDH->e_lfanew + pINTH->FileHeader.SizeOfOptionalHeader + sizeof(IMAGE_NT_HEADERS) - sizeof(IMAGE_OPTIONAL_HEADER);

		if ((machine == IMAGE_FILE_MACHINE_I386) &&
			(pINTH->FileHeader.SizeOfOptionalHeader >= sizeof(IMAGE_OPTIONAL_HEADER32)) &&
			(pINTH->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC)) {
			pIDD = (PIMAGE_DATA_DIRECTORY)((uint8_t*)pINTH + offsetof(IMAGE_NT_HEADERS32, OptionalHeader.DataDirectory));
			base = *(uint32_t*)((uint8_t*)pINTH + offsetof(IMAGE_NT_HEADERS32, OptionalHeader.ImageBase));
		}
		else if ((machine == IMAGE_FILE_MACHINE_AMD64) &&
			(pINTH->FileHeader.SizeOfOptionalHeader >= sizeof(IMAGE_OPTIONAL_HEADER64)) &&
			(pINTH->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC)) {
			pIDD = (PIMAGE_DATA_DIRECTORY)((uint8_t*)pINTH + offsetof(IMAGE_NT_HEADERS64, OptionalHeader.DataDirectory));
			base = *(ULONGLONG*)((uint8_t*)pINTH + offsetof(IMAGE_NT_HEADERS64, OptionalHeader.ImageBase));
		}
		else return RESULT_CORRUPTED;

		// Debugging information entry
		uint32_t dbgAddr = pIDD[IMAGE_DIRECTORY_ENTRY_DEBUG].VirtualAddress;
		uint32_t dbgSize = pIDD[IMAGE_DIRECTORY_ENTRY_DEBUG].Size;

		// Export information entry
		uint32_t expAddr = pIDD[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress;
		uint32_t expSize = pIDD[IMAGE_DIRECTORY_ENTRY_EXPORT].Size;

		// Resource directory
		uint32_t resAddr = pIDD[IMAGE_DIRECTORY_ENTRY_RESOURCE].VirtualAddress;
		uint32_t resSize = pIDD[IMAGE_DIRECTORY_ENTRY_RESOURCE].Size;

		// Reallocation information entry
		uint32_t relocAddr = pIDD[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress;
		uint32_t relocSize = pIDD[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size;

		// verify image integrity
		for (uint32_t idx = 0; idx < sections; idx++) {
			PIMAGE_SECTION_HEADER pISH = (PIMAGE_SECTION_HEADER)(map.ptr + offset + idx * sizeof(IMAGE_SECTION_HEADER));
			if (((uint8_t*)pISH + sizeof(IMAGE_SECTION_HEADER) > map.ptr + filesize) || (pISH->PointerToRawData + pISH->SizeOfRawData > filesize))
				return RESULT_CORRUPTED;

			// erase timestamp
			if (dbgSize >= sizeof(IMAGE_DEBUG_DIRECTORY) && Contains(pISH, dbgAddr, dbgSize)) {
				uint32_t shift = dbgAddr - pISH->VirtualAddress;
				pDBG = (PIMAGE_DEBUG_DIRECTORY)(map.ptr + shift + pISH->PointerToRawData);
				for (int i = dbgSize / sizeof(IMAGE_DEBUG_DIRECTORY); i > 0; i--)
					pDBG[i - 1].TimeDateStamp = 0;
			}

			// erase export timestamp
			if (expSize >= sizeof(IMAGE_EXPORT_DIRECTORY) && Contains(pISH, expAddr, expSize)) {
				uint32_t shift = expAddr - pISH->VirtualAddress;
				PIMAGE_EXPORT_DIRECTORY pEXP = (PIMAGE_EXPORT_DIRECTORY)(map.ptr + shift + pISH->PointerToRawData);
				pEXP->TimeDateStamp = 0;
			}

			// find realocation table
			if ((relocSize >= sizeof(IMAGE_BASE_RELOCATION)) && Contains(pISH, relocAddr, relocSize)) {
				uint32_t shift = relocAddr - pISH->VirtualAddress;
				pRealloc = map.ptr + shift + pISH->PointerToRawData;
			}
		}

		for (size_t idx = 0; idx < sections; idx++) {
			PIMAGE_SECTION_HEADER pISH = (PIMAGE_SECTION_HEADER)(map.ptr + offset + idx * sizeof(IMAGE_SECTION_HEADER));

			if (((uint8_t*)pISH + sizeof(IMAGE_SECTION_HEADER) > map.ptr + filesize) || (pISH->PointerToRawData + pISH->SizeOfRawData > filesize))
				return RESULT_CORRUPTED;

			// erase debug information
			if (pDBG && pDBG->SizeOfData > 0)
				if (pDBG->PointerToRawData >= pISH->PointerToRawData && pDBG->PointerToRawData + pDBG->SizeOfData <= pISH->PointerToRawData + pISH->SizeOfRawData)
					ZeroMemory(map.ptr + pDBG->PointerToRawData, pDBG->SizeOfData);

			// patch resources
			if (resSize > 0 && Contains(pISH, resAddr, resSize)) {
				uint32_t shift = resAddr - pISH->VirtualAddress + pISH->PointerToRawData;
				IMAGE_RESOURCE_DIRECTORY *pIRD = (IMAGE_RESOURCE_DIRECTORY*)(map.ptr + shift);
				PatchResourcesDirectory(pIRD, map.ptr + shift);
			}

			// rebase to zero address
			if (pRealloc) {
				uint32_t blocklen = relocSize;
				PIMAGE_BASE_RELOCATION pIBR = (PIMAGE_BASE_RELOCATION)pRealloc;
				while (pIBR) {
					if (Contains(pISH, pIBR->VirtualAddress) && pIBR->SizeOfBlock <= blocklen) {
						uint32_t shift = pIBR->VirtualAddress - pISH->VirtualAddress + pISH->PointerToRawData;
						int len = pIBR->SizeOfBlock - sizeof(IMAGE_BASE_RELOCATION);
						PWORD pw = (PWORD)((uint8_t*)pIBR + sizeof(IMAGE_BASE_RELOCATION));

						while (len > 0) {
							uint32_t type = *pw >> 12;
							uint32_t addr = (*pw & 0x0FFF);
							uint8_t *pAddr = map.ptr + shift + addr;

							switch (type) {
							case IMAGE_REL_BASED_HIGHLOW:
								if (addr + pIBR->VirtualAddress + sizeof(uint32_t) >= pISH->VirtualAddress + pISH->SizeOfRawData) {
									len = 0;
									break;
								}
								*(PDWORD)pAddr = (uint32_t)((*(PDWORD)pAddr) - (uint32_t)base);
								break;

							case IMAGE_REL_BASED_DIR64:
								if (addr + pIBR->VirtualAddress + sizeof(ULONGLONG) >= pISH->VirtualAddress + pISH->SizeOfRawData) {
									len = 0;
									break;
								}
								*(ULONGLONG*)pAddr = (ULONGLONG)((*(ULONGLONG*)pAddr) - base);
								break;

							case IMAGE_REL_BASED_ABSOLUTE:
								// stop processing
								len = 0;
								break;

							case IMAGE_REL_BASED_HIGH:
							case IMAGE_REL_BASED_LOW:
							case IMAGE_REL_BASED_HIGHADJ:
								break;
							}

							len -= sizeof(uint16_t);
							pw++;
						}
					}

					blocklen -= pIBR->SizeOfBlock;
					if (blocklen <= sizeof(IMAGE_BASE_RELOCATION))
						break;

					pIBR = (PIMAGE_BASE_RELOCATION)((uint8_t*)pIBR + pIBR->SizeOfBlock);
				}
			}

			mir_md5_append(&pms, map.ptr + pISH->PointerToRawData, pISH->SizeOfRawData);
		}
	}

	uint8_t digest[16];
	mir_md5_finish(&pms, digest);
	bin2hex(digest, sizeof(digest), szDest);
	return RESULT_OK;
}