mirror of
https://github.com/serge1/ELFIO.git
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133 lines
4.7 KiB
C++
133 lines
4.7 KiB
C++
/*
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Copyright (C) 2001-present by Serge Lamikhov-Center
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in
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all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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THE SOFTWARE.
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*/
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/*
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* This example shows how to create ELF executable file for Linux on x86-64
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*
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* Instructions:
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* 1. Compile and link this file with ELFIO library
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* g++ writer.cpp -o writer
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* 2. Execute result file writer
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* ./writer
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* 3. Add executable flag for the output file
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* chmod +x hello_x86_64
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* 4. Run the result file:
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* ./hello_x86_64
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*/
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#include <elfio/elfio.hpp>
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using namespace ELFIO;
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const Elf64_Addr CODE_ADDR = 0x00401000;
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const Elf_Xword PAGE_SIZE = 0x1000;
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const Elf64_Addr DATA_ADDR = CODE_ADDR + PAGE_SIZE;
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int main( void )
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{
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elfio writer;
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// You can't proceed without this function call!
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writer.create( ELFCLASS64, ELFDATA2LSB );
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writer.set_os_abi( ELFOSABI_LINUX );
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writer.set_type( ET_EXEC );
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writer.set_machine( EM_X86_64 );
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// Create code section
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section* text_sec = writer.sections.add( ".text" );
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text_sec->set_type( SHT_PROGBITS );
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text_sec->set_flags( SHF_ALLOC | SHF_EXECINSTR );
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text_sec->set_addr_align( 0x10 );
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// Add data into it
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char text[] = {
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'\xB8', '\x04', '\x00', '\x00', '\x00', // mov eax, 4
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'\xBB', '\x01', '\x00', '\x00', '\x00', // mov ebx, 1
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'\xB9', '\x00', '\x00', '\x00', '\x00', // mov ecx, msg
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'\xBA', '\x0E', '\x00', '\x00', '\x00', // mov edx, 14
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'\xCD', '\x80', // int 0x80
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'\xB8', '\x01', '\x00', '\x00', '\x00', // mov eax, 1
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'\xCD', '\x80' // int 0x80
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};
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// Adjust data address for 'msg'
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*(uint32_t*)( text + 11 ) = DATA_ADDR;
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text_sec->set_data( text, sizeof( text ) );
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// Create a loadable segment
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segment* text_seg = writer.segments.add();
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text_seg->set_type( PT_LOAD );
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text_seg->set_virtual_address( CODE_ADDR );
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text_seg->set_physical_address( CODE_ADDR );
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text_seg->set_flags( PF_X | PF_R );
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text_seg->set_align( PAGE_SIZE );
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// Add code section into program segment
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text_seg->add_section( text_sec, text_sec->get_addr_align() );
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// Create data section
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section* data_sec = writer.sections.add( ".data" );
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data_sec->set_type( SHT_PROGBITS );
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data_sec->set_flags( SHF_ALLOC | SHF_WRITE );
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data_sec->set_addr_align( 0x4 );
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char data[] = {
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'\x48', '\x65', '\x6C', '\x6C', '\x6F', // msg: db 'Hello, World!', 10
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'\x2C', '\x20', '\x57', '\x6F', '\x72',
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'\x6C', '\x64', '\x21', '\x0A' };
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data_sec->set_data( data, sizeof( data ) );
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// Create a read/write segment
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segment* data_seg = writer.segments.add();
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data_seg->set_type( PT_LOAD );
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data_seg->set_virtual_address( DATA_ADDR );
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data_seg->set_physical_address( DATA_ADDR );
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data_seg->set_flags( PF_W | PF_R );
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data_seg->set_align( PAGE_SIZE );
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// Add code section into program segment
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data_seg->add_section( data_sec, data_sec->get_addr_align() );
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// Add optional signature for the file producer
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section* note_sec = writer.sections.add( ".note" );
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note_sec->set_type( SHT_NOTE );
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note_sec->set_addr_align( 1 );
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note_section_accessor note_writer( writer, note_sec );
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note_writer.add_note( 0x01, "Created by ELFIO", 0, 0 );
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char descr[6] = { 0x31, 0x32, 0x33, 0x34, 0x35, 0x36 };
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note_writer.add_note( 0x01, "Never easier!", descr, sizeof( descr ) );
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// Setup entry point. Usually, a linker sets this address on base of
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// ‘_start’ label.
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// In this example, the code starts at the first address of the
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// 'text_seg' segment. Therefore, the start address is set
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// to be equal to the segment location
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writer.set_entry( text_seg->get_virtual_address() );
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// Create ELF file
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writer.save( "hello_x86_64" );
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return 0;
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}
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