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author | Francis Rowe <info@gluglug.org.uk> | 2014-12-23 19:33:45 (EST) |
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committer | Francis Rowe <info@gluglug.org.uk> | 2014-12-23 19:42:02 (EST) |
commit | 8ff050d3893f0115b8bd3f1feda5d032f89fbc32 (patch) | |
tree | 6f8a493c19c2f4bcc59adebb7a88bcea97a7b3ea /resources/utilities/ich9deblob/main.c | |
parent | 1082934d042a5f8b397afc48a0b92edd8d779610 (diff) | |
download | libreboot-8ff050d3893f0115b8bd3f1feda5d032f89fbc32.zip libreboot-8ff050d3893f0115b8bd3f1feda5d032f89fbc32.tar.gz libreboot-8ff050d3893f0115b8bd3f1feda5d032f89fbc32.tar.bz2 |
ich9deblob: Replace makefile (use dependencies)
Use .h and .c files properly. Use header guards. Define function
names in .h files (actual functions in the .c files), and so on.
Move all functions from the .h files to corresponding .c files.
Diffstat (limited to 'resources/utilities/ich9deblob/main.c')
-rw-r--r-- | resources/utilities/ich9deblob/main.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/resources/utilities/ich9deblob/main.c b/resources/utilities/ich9deblob/main.c new file mode 100644 index 0000000..f469f83 --- /dev/null +++ b/resources/utilities/ich9deblob/main.c @@ -0,0 +1,248 @@ +/* + * main.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. */ + +/* + * 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 850 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 <stdio.h> +#include <string.h> +#include "descriptor/descriptor.h" /* structs describing what's in the descriptor region */ +#include "gbe/gbe.h" /* structs describing what's in the gbe region */ +#include "x86compatibility.h" /* system/compiler compatibility checks. This code is not portable. */ + +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; + char deblobbedDescriptorBuffer[DESCRIPTORREGIONSIZE]; + 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; + char deblobbedGbeBuffer8k[GBEREGIONSIZE_8K]; + 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"); + 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); + 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); + 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); + + /* + * Modify the Gbe region (see function for details) + */ + deblobbedGbeStruct8k = deblobbedGbeStructFromFactory(factoryGbeStruct8k); + + /* + * ------------------------------------------------------------------ + * Create the file with the modified descriptor and gbe inside + * ------------------------------------------------------------------ + */ + + /* + * Convert the deblobbed descriptor and gbe back to byte arrays, so that they + * can more easily be written to files: + * deblobbed descriptor region + */ + memcpy(&deblobbedDescriptorBuffer, &deblobbedDescriptorStruct, DESCRIPTORREGIONSIZE); /* descriptor */ + memcpy(&deblobbedGbeBuffer8k, &deblobbedGbeStruct8k, GBEREGIONSIZE_8K); /* gbe */ + + /* delete old file before continuing */ + remove(deblobbedDescriptorFilename); + + /* open new file for writing the deblobbed descriptor+gbe */ + fileStream = fopen(deblobbedDescriptorFilename, "ab"); + + /* write the descriptor region into the first part */ + if (DESCRIPTORREGIONSIZE != fwrite(deblobbedDescriptorBuffer, sizeof(char), DESCRIPTORREGIONSIZE, fileStream)) + { + printf("\nerror: writing descriptor region failed\n"); + return 1; + } + + /* add gbe to the end of the file */ + if (GBEREGIONSIZE_8K != fwrite(deblobbedGbeBuffer8k, sizeof(char), GBEREGIONSIZE_8K, fileStream)) + { + printf("\nerror: writing GBe region failed\n"); + return 1; + } + + fclose(fileStream); + + printf("\ndeblobbed descriptor successfully created: deblobbed_descriptor.bin \n"); + + // ------------------------------------------------------------------------------------- + + printf("\nNow do: dd if=deblobbed_descriptor.bin of=libreboot.rom bs=1 count=12k conv=notrunc"); + printf("\n(in other words, add the modified descriptor+gbe to your ROM image)\n"); + + return 0; +} |