summaryrefslogtreecommitdiffstats
path: root/resources/utilities/ich9deblob/src/ich9deblob.c
blob: 360668607d540e3eb34b1bf77d5f8c7e11050ca0 (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
/*
 *  ich9deblob.c
 *  This file is part of the ich9deblob utility from the libreboot project
 * 
 * Purpose: disable and remove the ME from ich9m/gm45 machines in coreboot.
 *
 *  Copyright (C) 2014 Steve Shenton <sgsit@libreboot.org>
 *                     Francis Rowe <info@gluglug.org.uk>
 *
 *  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, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
/* Initially based on proof of concept by Steve Shenton. */
/* Original utility can be found at https://gitorious.org/ich9descriptortool */
 
/*
 * Read a factory.rom dump (ich9m/gm45 machines) and 
 * modify the flash descriptor to remove all regions except descriptor,
 * Gbe and BIOS. Set BIOS region to full size of the ROM image (after
 * the flash descriptor and gbe). Basically, deblob the descriptor.
 * 
 * This will will generate a concatenated descriptor+gbe dump suitable
 * for use in libreboot. Currently tested: ThinkPad X200 (coreboot/libreboot)
 */
 
/*
 * See docs/hcl/x200_remove_me.html for info plus links to datasheet (also linked below)
 * 
 * Info about flash descriptor (read page 845 onwards):
 * http://www.intel.co.uk/content/dam/doc/datasheet/io-controller-hub-9-datasheet.pdf
 * 
 * Info about Gbe region (read whole datasheet):
 * http://www.intel.co.uk/content/dam/doc/application-note/i-o-controller-hub-9m-82567lf-lm-v-nvm-map-appl-note.pdf
 * https://communities.intel.com/community/wired/blog/2010/10/14/how-to-basic-eeprom-checksums
 */

#include "ich9deblob.h"

int main(int argc, char *argv[])
{
	/*
	 * descriptor region. Will have an actual descriptor struct mapped to it (from the factory.rom dump)
	 * and then it will be modified (deblobbed) to remove the ME/AMT
	 */
	char factoryDescriptorBuffer[DESCRIPTORREGIONSIZE];
	struct DESCRIPTORREGIONRECORD factoryDescriptorStruct;
	struct DESCRIPTORREGIONRECORD deblobbedDescriptorStruct;
	
	/* 
	 * gbe region. Well have actual gbe buffer mapped to it (from the factory.rom dump)
	 * and then it will be modified to correct the main region
	 */
	char factoryGbeBuffer8k[GBEREGIONSIZE_8K];
	struct GBEREGIONRECORD_8K factoryGbeStruct8k;
	struct GBEREGIONRECORD_8K deblobbedGbeStruct8k;
	
	/*
	 * Used to store the location of the Gbe
	 * region inside the factory.rom image.
	 */
	unsigned int factoryGbeRegionStart;
	
	/* names of the files that this utility will handle */
	char* factoryRomFilename = "factory.rom";                       /* user-supplied factory.bin dump (original firmware) */
	char* deblobbedDescriptorFilename = "deblobbed_descriptor.bin"; /* descriptor+gbe: to be dd'd to beginning of a libreboot image */
	
	/* Used when reading the factory.rom to extract descriptor/gbe regions */
	unsigned int bufferLength;
	
	/* For storing the size of the factory.rom dump in bytes */
	unsigned int factoryRomSize;
	
	/*
	 * ------------------------------------------------------------------
	 * Compatibility checks. This version of ich9deblob is not yet portable.
	 * ------------------------------------------------------------------
	 */

	if (systemOrCompilerIncompatible(factoryDescriptorStruct, factoryGbeStruct8k)) return 1;
	/* If true, fail with error message */
	
	/*
	 * ------------------------------------------------------------------
	 * Extract the descriptor and gbe regions from the factory.rom dump
	 * ------------------------------------------------------------------
	 */
	FILE* fileStream = NULL;
	fileStream = fopen(factoryRomFilename, "rb"); /* open factory.rom */
	if (NULL == fileStream)
	{
		printf("\nerror: could not open factory.rom\n");
		fclose(fileStream);
		return 1;
	}
	printf("\nfactory.rom opened successfully\n");
	
	/* 
	 * Get the descriptor region dump from the factory.rom
	 * (goes in factoryDescriptorBuffer variable)
	 */
	bufferLength = fread(factoryDescriptorBuffer, sizeof(char), DESCRIPTORREGIONSIZE, fileStream);
	if (DESCRIPTORREGIONSIZE != bufferLength) // 
	{
		printf("\nerror: could not read descriptor from factory.rom (%i) bytes read\n", bufferLength);
		fclose(fileStream);
		return 1;
	}
	printf("\ndescriptor region read successfully\n");
	/*
	 * copy descriptor buffer into descriptor struct memory
	 * factoryDescriptorStruct is an instance of a struct that actually
	 * defines the locations of all these variables in the descriptor,
	 * as defined in the datasheets. This allows us to map the extracted
	 * descriptor over the struct so that it can then be modified
	 * for libreboot's purpose
	 */
	memcpy(&factoryDescriptorStruct, &factoryDescriptorBuffer, DESCRIPTORREGIONSIZE);
	/*
	 * ^ the above is just for reference if needed. The modifications will be made here:
	 */
	memcpy(&deblobbedDescriptorStruct, &factoryDescriptorBuffer, DESCRIPTORREGIONSIZE);
	
	/*
	 * Get the gbe region dump from the factory.rom
	 */

	/*
	 * get original GBe region location
	 * (it will be moved to the beginning of the flash, after the descriptor region)
	 * note for example, factoryGbeRegionStart is set to <<FLREGIONBITSHIFT of actual address (in C). this is how the addresses
	 * are stored in the descriptor.
	 */
	factoryGbeRegionStart = factoryDescriptorStruct.regionSection.flReg3.BASE << FLREGIONBITSHIFT;

	/*
	 * Set offset so that we can read the data from
	 * the gbe region
	 */
	fseek(fileStream, factoryGbeRegionStart, SEEK_SET);
	/* Read the gbe data from the factory.rom and put it in factoryGbeBuffer8k */
	bufferLength = fread(factoryGbeBuffer8k, sizeof(char), GBEREGIONSIZE_8K, fileStream);
	if (GBEREGIONSIZE_8K != bufferLength)
	{
		printf("\nerror: could not read GBe region from factory.rom (%i) bytes read\n", bufferLength);
		fclose(fileStream);
		return 1;
	}
	printf("\ngbe (8KiB) region read successfully\n");
	/*
	 * copy gbe buffer into gbe struct memory
	 * factoryGbeStruct8k is an instance of a struct that actually
	 * defines the locations of all these variables in the gbe,
	 * as defined in the datasheets. This allows us to map the extracted
	 * gbe over the struct so that it can then be modified
	 * for libreboot's purpose
	 */
	memcpy(&factoryGbeStruct8k, &factoryGbeBuffer8k, GBEREGIONSIZE_8K);
	/*
	 * the original factoryGbeStruct8k is only reference. Changes go here:
	 */
	memcpy(&deblobbedGbeStruct8k, &factoryGbeBuffer8k, GBEREGIONSIZE_8K);

	/* 
	 * Get size of ROM image
	 * This is needed for relocating the BIOS region (per descriptor)
	 */
	fseek(fileStream, 0L, SEEK_END);
	factoryRomSize = ftell(fileStream);

	printf("\nfactory.rom size: [%i] bytes\n", factoryRomSize);

	fclose(fileStream);
	
	/*
	 * ------------------------------------------------------------------
	 * Modify the descriptor and gbe regions, ready to go in libreboot.rom
	 * ------------------------------------------------------------------
	 */

	/*
	 * Disable the ME and Platform regions. Put Gbe at the beginning (after descriptor). 
	 * Also, extend the BIOS region to fill the ROM image (after descriptor+gbe).
	 */
	deblobbedDescriptorStruct = deblobbedDescriptorStructFromFactory(factoryDescriptorStruct, factoryRomSize);
	/*
	 * Debugging: show region locations in the 
	 * original descriptor and the modified one
	 */
	printDescriptorRegionLocations(factoryDescriptorStruct, "Original");
	printDescriptorRegionLocations(deblobbedDescriptorStruct, "Modified");

	/*
	 * Modify the Gbe region (see function for details)
	 */
	deblobbedGbeStruct8k = deblobbedGbeStructFromFactory(factoryGbeStruct8k);
	/*
	 * Debugging: show difference between Gbe checksums in the
	 * original gbe and the modified one
	 */
	printf("\n");
	printGbeChecksumDataFromStruct8k(factoryGbeStruct8k, "Original");
	printGbeChecksumDataFromStruct8k(deblobbedGbeStruct8k, "Modified");

	/*
	 * ------------------------------------------------------------------
	 * Create the file with the modified descriptor and gbe inside
	 * ------------------------------------------------------------------
	 */

	printf("\n");
	if (notCreatedDescriptorGbeFile(deblobbedDescriptorStruct, deblobbedGbeStruct8k, deblobbedDescriptorFilename)) {
		return 1;
	}
	
	/*
	 * ------------------------------------------------------------------
	 * Generate ich9gen data (C code that will recreate the deblobbed descriptor+gbe from scratch)
	 * ------------------------------------------------------------------
	 */
	/* Code for generating the Gbe struct */
	/* mkgbe.h */
	if (notCreatedHFileForGbeCFile("mkgbe.h", "mkgbe.c")) {
		return 1;
	} /* and now mkgbe.c */
	if (notCreatedCFileFromGbeStruct4k(deblobbedGbeStruct8k.backup, "mkgbe.c", "mkgbe.h")) {
		return 1;
	}
	/* Code for generating the Descriptor struct */
	/* mkdescriptor.h */
	if (notCreatedHFileForDescriptorCFile("mkdescriptor.h", "mkdescriptor.c")) {
		return 1;
	} /* and now mkdescriptor.c */
	if (notCreatedCFileFromDescriptorStruct(deblobbedDescriptorStruct, "mkdescriptor.c", "mkdescriptor.h")) {
		return 1;
	}
	printf("The modified descriptor and gbe regions have also been dumped as src files: mkgbe.c, mkgbe.h, mkdescriptor.c, mkdescriptor.h\n");
	printf("To use these in ich9gen, place them in src/ich9gen/ and re-build ich9gen.\n\n");

	return 0;
}