diff options
Diffstat (limited to 'src/util/efilink.c')
| -rw-r--r-- | src/util/efilink.c | 515 |
1 files changed, 0 insertions, 515 deletions
diff --git a/src/util/efilink.c b/src/util/efilink.c deleted file mode 100644 index 17b99d293..000000000 --- a/src/util/efilink.c +++ /dev/null @@ -1,515 +0,0 @@ -#include <stdint.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include <errno.h> -#include <bfd.h> - -struct bfd_file { - bfd *bfd; - asymbol **symtab; - long symcount; -}; - -struct pe_relocs { - struct pe_relocs *next; - unsigned long start_rva; - unsigned int used_relocs; - unsigned int total_relocs; - uint16_t *relocs; -}; - -/** - * Allocate memory - * - * @v len Length of memory to allocate - * @ret ptr Pointer to allocated memory - */ -static void * xmalloc ( size_t len ) { - void *ptr; - - ptr = malloc ( len ); - if ( ! ptr ) { - fprintf ( stderr, "Could not allocate %zd bytes\n", len ); - exit ( 1 ); - } - - return ptr; -} - -/** - * Generate entry in PE relocation table - * - * @v pe_reltab PE relocation table - * @v rva RVA - * @v size Size of relocation entry - */ -static void generate_pe_reloc ( struct pe_relocs **pe_reltab, - unsigned long rva, size_t size ) { - unsigned long start_rva; - uint16_t reloc; - struct pe_relocs *pe_rel; - uint16_t *relocs; - - /* Construct */ - start_rva = ( rva & ~0xfff ); - reloc = ( rva & 0xfff ); - switch ( size ) { - case 8: - reloc |= 0xa000; - break; - case 4: - reloc |= 0x3000; - break; - case 2: - reloc |= 0x2000; - break; - default: - fprintf ( stderr, "Unsupported relocation size %zd\n", size ); - exit ( 1 ); - } - - /* Locate or create PE relocation table */ - for ( pe_rel = *pe_reltab ; pe_rel ; pe_rel = pe_rel->next ) { - if ( pe_rel->start_rva == start_rva ) - break; - } - if ( ! pe_rel ) { - pe_rel = xmalloc ( sizeof ( *pe_rel ) ); - memset ( pe_rel, 0, sizeof ( *pe_rel ) ); - pe_rel->next = *pe_reltab; - *pe_reltab = pe_rel; - pe_rel->start_rva = start_rva; - } - - /* Expand relocation list if necessary */ - if ( pe_rel->used_relocs < pe_rel->total_relocs ) { - relocs = pe_rel->relocs; - } else { - pe_rel->total_relocs = ( pe_rel->total_relocs ? - ( pe_rel->total_relocs * 2 ) : 256 ); - relocs = xmalloc ( pe_rel->total_relocs * - sizeof ( pe_rel->relocs[0] ) ); - memset ( relocs, 0, - pe_rel->total_relocs * sizeof ( pe_rel->relocs[0] ) ); - memcpy ( relocs, pe_rel->relocs, - pe_rel->used_relocs * sizeof ( pe_rel->relocs[0] ) ); - free ( pe_rel->relocs ); - pe_rel->relocs = relocs; - } - - /* Store relocation */ - pe_rel->relocs[ pe_rel->used_relocs++ ] = reloc; -} - -/** - * Calculate size of binary PE relocation table - * - * @v pe_reltab PE relocation table - * @v buffer Buffer to contain binary table, or NULL - * @ret size Size of binary table - */ -static size_t output_pe_reltab ( struct pe_relocs *pe_reltab, - void *buffer ) { - struct pe_relocs *pe_rel; - unsigned int num_relocs; - size_t size; - size_t total_size = 0; - - for ( pe_rel = pe_reltab ; pe_rel ; pe_rel = pe_rel->next ) { - num_relocs = ( ( pe_rel->used_relocs + 1 ) & ~1 ); - size = ( sizeof ( uint32_t ) /* VirtualAddress */ + - sizeof ( uint32_t ) /* SizeOfBlock */ + - ( num_relocs * sizeof ( uint16_t ) ) ); - if ( buffer ) { - *( (uint32_t *) ( buffer + total_size + 0 ) ) - = pe_rel->start_rva; - *( (uint32_t *) ( buffer + total_size + 4 ) ) = size; - memcpy ( ( buffer + total_size + 8 ), pe_rel->relocs, - ( num_relocs * sizeof ( uint16_t ) ) ); - } - total_size += size; - } - - return total_size; -} - -/** - * Read symbol table - * - * @v bfd BFD file - */ -static void read_symtab ( struct bfd_file *bfd ) { - long symtab_size; - - /* Get symbol table size */ - symtab_size = bfd_get_symtab_upper_bound ( bfd->bfd ); - if ( symtab_size < 0 ) { - bfd_perror ( "Could not get symbol table upper bound" ); - exit ( 1 ); - } - - /* Allocate and read symbol table */ - bfd->symtab = xmalloc ( symtab_size ); - bfd->symcount = bfd_canonicalize_symtab ( bfd->bfd, bfd->symtab ); - if ( bfd->symcount < 0 ) { - bfd_perror ( "Cannot read symbol table" ); - exit ( 1 ); - } -} - -/** - * Read relocation table - * - * @v bfd BFD file - * @v section Section - * @v symtab Symbol table - * @ret reltab Relocation table - */ -static arelent ** read_reltab ( struct bfd_file *bfd, asection *section ) { - long reltab_size; - arelent **reltab; - long numrels; - - /* Get relocation table size */ - reltab_size = bfd_get_reloc_upper_bound ( bfd->bfd, section ); - if ( reltab_size < 0 ) { - bfd_perror ( "Could not get relocation table upper bound" ); - exit ( 1 ); - } - - /* Allocate and read relocation table */ - reltab = xmalloc ( reltab_size ); - numrels = bfd_canonicalize_reloc ( bfd->bfd, section, reltab, - bfd->symtab ); - if ( numrels < 0 ) { - bfd_perror ( "Cannot read relocation table" ); - exit ( 1 ); - } - - return reltab; -} - - -/** - * Open input BFD file - * - * @v filename File name - * @ret ibfd BFD file - */ -static struct bfd_file * open_input_bfd ( const char *filename ) { - struct bfd_file *ibfd; - - /* Create BFD file */ - ibfd = xmalloc ( sizeof ( *ibfd ) ); - memset ( ibfd, 0, sizeof ( *ibfd ) ); - - /* Open the file */ - ibfd->bfd = bfd_openr ( filename, NULL ); - if ( ! ibfd->bfd ) { - fprintf ( stderr, "Cannot open %s: ", filename ); - bfd_perror ( NULL ); - exit ( 1 ); - } - - /* The call to bfd_check_format() must be present, otherwise - * we get a segfault from later BFD calls. - */ - if ( bfd_check_format ( ibfd->bfd, bfd_object ) < 0 ) { - fprintf ( stderr, "%s is not an object file\n", filename ); - exit ( 1 ); - } - - /* Read symbols and relocation entries */ - read_symtab ( ibfd ); - - return ibfd; -} - -/** - * Open output BFD file - * - * @v filename File name - * @v ibfd Input BFD file - * @ret obfd BFD file - */ -static struct bfd_file * open_output_bfd ( const char *filename, - struct bfd_file *ibfd ) { - struct bfd_file *obfd; - asection *isection; - asection *osection; - - /* - * Most of this code is based on what objcopy.c does. - * - */ - - /* Create BFD file */ - obfd = xmalloc ( sizeof ( *obfd ) ); - memset ( obfd, 0, sizeof ( *obfd ) ); - - /* Open the file */ - obfd->bfd = bfd_openw ( filename, ibfd->bfd->xvec->name ); - if ( ! obfd->bfd ) { - fprintf ( stderr, "Cannot open %s: ", filename ); - bfd_perror ( NULL ); - exit ( 1 ); - } - - /* Copy per-file data */ - if ( ! bfd_set_arch_mach ( obfd->bfd, bfd_get_arch ( ibfd->bfd ), - bfd_get_mach ( ibfd->bfd ) ) ) { - bfd_perror ( "Cannot copy architecture" ); - exit ( 1 ); - } - if ( ! bfd_set_format ( obfd->bfd, bfd_get_format ( ibfd->bfd ) ) ) { - bfd_perror ( "Cannot copy format" ); - exit ( 1 ); - } - if ( ! bfd_copy_private_header_data ( ibfd->bfd, obfd->bfd ) ) { - bfd_perror ( "Cannot copy private header data" ); - exit ( 1 ); - } - - /* Create sections */ - for ( isection = ibfd->bfd->sections ; isection ; - isection = isection->next ) { - osection = bfd_make_section_anyway ( obfd->bfd, - isection->name ); - if ( ! osection ) { - bfd_perror ( "Cannot create section" ); - exit ( 1 ); - } - if ( ! bfd_set_section_flags ( obfd->bfd, osection, - isection->flags ) ) { - bfd_perror ( "Cannot copy section flags" ); - exit ( 1 ); - } - if ( ! bfd_set_section_size ( obfd->bfd, osection, - bfd_section_size ( ibfd->bfd, isection ) ) ) { - bfd_perror ( "Cannot copy section size" ); - exit ( 1 ); - } - if ( ! bfd_set_section_vma ( obfd->bfd, osection, - bfd_section_vma ( ibfd->bfd, isection ) ) ) { - bfd_perror ( "Cannot copy section VMA" ); - exit ( 1 ); - } - osection->lma = bfd_section_lma ( ibfd->bfd, isection ); - if ( ! bfd_set_section_alignment ( obfd->bfd, osection, - bfd_section_alignment ( ibfd->bfd, isection ) ) ) { - bfd_perror ( "Cannot copy section alignment" ); - exit ( 1 ); - } - osection->entsize = isection->entsize; - isection->output_section = osection; - isection->output_offset = 0; - if ( ! bfd_copy_private_section_data ( ibfd->bfd, isection, - obfd->bfd, osection ) ){ - bfd_perror ( "Cannot copy section private data" ); - exit ( 1 ); - } - } - - /* Copy symbol table */ - bfd_set_symtab ( obfd->bfd, ibfd->symtab, ibfd->symcount ); - obfd->symtab = ibfd->symtab; - - return obfd; -} - -/** - * Copy section from input BFD file to output BFD file - * - * @v obfd Output BFD file - * @v ibfd Input BFD file - * @v section Section - */ -static void copy_bfd_section ( struct bfd_file *obfd, struct bfd_file *ibfd, - asection *isection ) { - size_t size; - void *buf; - arelent **reltab; - arelent **rel; - char *errmsg; - - /* Read in original section */ - size = bfd_section_size ( ibfd->bfd, isection ); - if ( ! size ) - return; - buf = xmalloc ( size ); - if ( ( ! bfd_get_section_contents ( ibfd->bfd, isection, - buf, 0, size ) ) ) { - fprintf ( stderr, "Cannot read section %s: ", isection->name ); - bfd_perror ( NULL ); - exit ( 1 ); - } - - /* Perform relocations. We do this here, rather than letting - * ld do it for us when creating the input ELF file, so that - * we can change symbol values as a result of having created - * the .reloc section. - */ - reltab = read_reltab ( ibfd, isection ); - for ( rel = reltab ; *rel ; rel++ ) { - bfd_perform_relocation ( ibfd->bfd, *rel, buf, isection, - NULL, &errmsg ); - } - free ( reltab ); - - /* Write out modified section */ - if ( ( ! bfd_set_section_contents ( obfd->bfd, - isection->output_section, - buf, 0, size ) ) ) { - fprintf ( stderr, "Cannot write section %s: ", - isection->output_section->name ); - bfd_perror ( NULL ); - exit ( 1 ); - } - - free ( buf ); -} - -/** - * Process relocation record - * - * @v section Section - * @v rel Relocation entry - * @v pe_reltab PE relocation table to fill in - */ -static void process_reloc ( asection *section, arelent *rel, - struct pe_relocs **pe_reltab ) { - reloc_howto_type *howto = rel->howto; - asymbol *sym = *(rel->sym_ptr_ptr); - unsigned long offset = ( section->lma + rel->address ); - - if ( bfd_is_abs_section ( sym->section ) ) { - /* Skip absolute symbols; the symbol value won't - * change when the object is loaded. - */ - } else if ( strcmp ( howto->name, "R_X86_64_64" ) == 0 ) { - /* Generate an 8-byte PE relocation */ - generate_pe_reloc ( pe_reltab, offset, 8 ); - } else if ( ( strcmp ( howto->name, "R_386_32" ) == 0 ) || - ( strcmp ( howto->name, "R_X86_64_32" ) == 0 ) ) { - /* Generate a 4-byte PE relocation */ - generate_pe_reloc ( pe_reltab, offset, 4 ); - } else if ( strcmp ( howto->name, "R_386_16" ) == 0 ) { - /* Generate a 2-byte PE relocation */ - generate_pe_reloc ( pe_reltab, offset, 2 ); - } else if ( ( strcmp ( howto->name, "R_386_PC32" ) == 0 ) || - ( strcmp ( howto->name, "R_X86_64_PC32" ) == 0 ) ) { - /* Skip PC-relative relocations; all relative offsets - * remain unaltered when the object is loaded. - */ - } else { - fprintf ( stderr, "Unrecognised relocation type %s\n", - howto->name ); - exit ( 1 ); - } -} - -/** - * Create .reloc section - * - * obfd Output BFD file - * section .reloc section in output file - * pe_reltab PE relocation table - */ -static void create_reloc_section ( struct bfd_file *obfd, asection *section, - struct pe_relocs *pe_reltab ) { - size_t raw_size; - size_t size; - size_t old_size; - void *buf; - asymbol **sym; - - /* Build binary PE relocation table */ - raw_size = output_pe_reltab ( pe_reltab, NULL ); - size = ( ( raw_size + 31 ) & ~31 ); - buf = xmalloc ( size ); - memset ( buf, 0, size ); - output_pe_reltab ( pe_reltab, buf ); - - /* Write .reloc section */ - old_size = bfd_section_size ( obfd->bfd, section ); - if ( ! bfd_set_section_size ( obfd->bfd, section, size ) ) { - bfd_perror ( "Cannot resize .reloc section" ); - exit ( 1 ); - } - if ( ! bfd_set_section_contents ( obfd->bfd, section, - buf, 0, size ) ) { - bfd_perror ( "Cannot set .reloc section contents" ); - exit ( 1 ); - } - - /* Update symbols pertaining to the relocation directory */ - for ( sym = obfd->symtab ; *sym ; sym++ ) { - if ( strcmp ( (*sym)->name, "_reloc_memsz" ) == 0 ) { - (*sym)->value = size; - } else if ( strcmp ( (*sym)->name, "_reloc_filesz" ) == 0 ){ - (*sym)->value = raw_size; - } else if ( strcmp ( (*sym)->name, "_filesz" ) == 0 ) { - (*sym)->value += ( size - old_size ); - } - } -} - -int main ( int argc, const char *argv[] ) { - const char *iname; - const char *oname; - struct bfd_file *ibfd; - struct bfd_file *obfd; - asection *section; - arelent **reltab; - arelent **rel; - struct pe_relocs *pe_reltab = NULL; - asection *reloc_section; - - /* Initialise libbfd */ - bfd_init(); - - /* Identify intput and output files */ - if ( argc != 3 ) { - fprintf ( stderr, "Syntax: %s infile outfile\n", argv[0] ); - exit ( 1 ); - } - iname = argv[1]; - oname = argv[2]; - - /* Open BFD files */ - ibfd = open_input_bfd ( iname ); - obfd = open_output_bfd ( oname, ibfd ); - - /* Process relocations in all sections */ - for ( section = ibfd->bfd->sections ; section ; - section = section->next ) { - reltab = read_reltab ( ibfd, section ); - for ( rel = reltab ; *rel ; rel++ ) { - process_reloc ( section, *rel, &pe_reltab ); - } - free ( reltab ); - } - - /* Create modified .reloc section */ - reloc_section = bfd_get_section_by_name ( obfd->bfd, ".reloc" ); - if ( ! reloc_section ) { - fprintf ( stderr, "Cannot find .reloc section\n" ); - exit ( 1 ); - } - create_reloc_section ( obfd, reloc_section, pe_reltab ); - - /* Copy other section contents */ - for ( section = ibfd->bfd->sections ; section ; - section = section->next ) { - if ( section->output_section != reloc_section ) - copy_bfd_section ( obfd, ibfd, section ); - } - - /* Write out files and clean up */ - bfd_close ( obfd->bfd ); - bfd_close ( ibfd->bfd ); - - return 0; -} |