e4c9eaa7e8
Change-Id: Ie0e9c05569ca9b02fd36f31fd7323f02b14e1b60
770 lines
24 KiB
C
770 lines
24 KiB
C
/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id$
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*
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* Copyright (C) 2011 Amaury Pouly
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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#define _POSIX_C_SOURCE 200809L /* for strdup */
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#include "elf.h"
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#include "misc.h"
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#include <stdarg.h>
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#include <string.h>
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/**
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* Definitions
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* taken from elf.h linux header
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* based on ELF specification
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* based on ARM ELF specification
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*/
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typedef uint16_t Elf32_Half;
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typedef uint32_t Elf32_Word;
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typedef int32_t Elf32_Sword;
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typedef uint32_t Elf32_Addr;
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typedef uint32_t Elf32_Off;
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typedef uint16_t Elf32_Section;
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#define EI_NIDENT 16
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typedef struct
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{
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unsigned char e_ident[EI_NIDENT]; /* Magic number and other info */
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Elf32_Half e_type; /* Object file type */
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Elf32_Half e_machine; /* Architecture */
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Elf32_Word e_version; /* Object file version */
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Elf32_Addr e_entry; /* Entry point virtual address */
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Elf32_Off e_phoff; /* Program header table file offset */
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Elf32_Off e_shoff; /* Section header table file offset */
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Elf32_Word e_flags; /* Processor-specific flags */
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Elf32_Half e_ehsize; /* ELF header size in bytes */
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Elf32_Half e_phentsize; /* Program header table entry size */
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Elf32_Half e_phnum; /* Program header table entry count */
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Elf32_Half e_shentsize; /* Section header table entry size */
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Elf32_Half e_shnum; /* Section header table entry count */
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Elf32_Half e_shstrndx; /* Section header string table index */
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}Elf32_Ehdr;
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#define EI_MAG0 0 /* File identification byte 0 index */
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#define ELFMAG0 0x7f /* Magic number byte 0 */
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#define EI_MAG1 1 /* File identification byte 1 index */
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#define ELFMAG1 'E' /* Magic number byte 1 */
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#define EI_MAG2 2 /* File identification byte 2 index */
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#define ELFMAG2 'L' /* Magic number byte 2 */
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#define EI_MAG3 3 /* File identification byte 3 index */
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#define ELFMAG3 'F' /* Magic number byte 3 */
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#define EI_CLASS 4 /* File class byte index */
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#define ELFCLASS32 1 /* 32-bit objects */
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#define EI_DATA 5 /* Data encoding byte index */
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#define ELFDATA2LSB 1 /* 2's complement, little endian */
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#define EI_VERSION 6 /* File version byte index, Value must be EV_CURRENT */
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#define EI_OSABI 7 /* OS ABI identification */
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#define ELFOSABI_NONE 0 /* UNIX System V ABI */
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#define ELFOSABI_ARM_AEABI 64 /* ARM EABI */
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#define ELFOSABI_ARM 97 /* ARM */
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#define EI_ABIVERSION 8 /* ABI version */
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#define EI_PAD 9 /* Byte index of padding bytes */
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#define ET_EXEC 2 /* Executable file */
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#define EM_ARM 40 /* ARM */
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#define EV_CURRENT 1 /* Current version */
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#define EF_ARM_HASENTRY 0x00000002
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#define SHN_UNDEF 0 /* Undefined section */
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typedef struct
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{
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Elf32_Word sh_name; /* Section name (string tbl index) */
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Elf32_Word sh_type; /* Section type */
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Elf32_Word sh_flags; /* Section flags */
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Elf32_Addr sh_addr; /* Section virtual addr at execution */
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Elf32_Off sh_offset; /* Section file offset */
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Elf32_Word sh_size; /* Section size in bytes */
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Elf32_Word sh_link; /* Link to another section */
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Elf32_Word sh_info; /* Additional section information */
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Elf32_Word sh_addralign; /* Section alignment */
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Elf32_Word sh_entsize; /* Entry size if section holds table */
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}Elf32_Shdr;
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#define SHT_NULL 0 /* Section header table entry unused */
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#define SHT_PROGBITS 1 /* Program data */
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#define SHT_SYMTAB 2 /* Symbol table */
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#define SHT_STRTAB 3 /* String table */
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#define SHT_RELA 4 /* Relocation entries with addends */
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#define SHT_HASH 5 /* Symbol hash table */
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#define SHT_DYNAMIC 6 /* Dynamic linking information */
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#define SHT_NOTE 7 /* Notes */
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#define SHT_NOBITS 8 /* Program space with no data (bss) */
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#define SHT_REL 9 /* Relocation entries, no addends */
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#define SHT_SHLIB 10 /* Reserved */
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#define SHT_DYNSYM 11 /* Dynamic linker symbol table */
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#define SHT_INIT_ARRAY 14 /* Array of constructors */
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#define SHT_FINI_ARRAY 15 /* Array of destructors */
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#define SHT_PREINIT_ARRAY 16 /* Array of pre-constructors */
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#define SHT_GROUP 17 /* Section group */
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#define SHT_SYMTAB_SHNDX 18 /* Extended section indeces */
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#define SHT_NUM 19 /* Number of defined types. */
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#define SHF_WRITE (1 << 0) /* Writable */
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#define SHF_ALLOC (1 << 1) /* Occupies memory during execution */
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#define SHF_EXECINSTR (1 << 2) /* Executable */
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#define SHF_MERGE (1 << 4) /* Might be merged */
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#define SHF_STRINGS (1 << 5) /* Contains nul-terminated strings */
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typedef struct
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{
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Elf32_Word p_type; /* Segment type */
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Elf32_Off p_offset; /* Segment file offset */
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Elf32_Addr p_vaddr; /* Segment virtual address */
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Elf32_Addr p_paddr; /* Segment physical address */
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Elf32_Word p_filesz; /* Segment size in file */
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Elf32_Word p_memsz; /* Segment size in memory */
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Elf32_Word p_flags; /* Segment flags */
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Elf32_Word p_align; /* Segment alignment */
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}Elf32_Phdr;
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#define PT_LOAD 1 /* Loadable program segment */
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#define PF_X (1 << 0) /* Segment is executable */
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#define PF_W (1 << 1) /* Segment is writable */
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#define PF_R (1 << 2) /* Segment is readable */
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void elf_init(struct elf_params_t *params)
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{
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memset(params, 0, sizeof(struct elf_params_t));
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}
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extern void *xmalloc(size_t s);
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static struct elf_section_t *elf_add_section(struct elf_params_t *params)
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{
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struct elf_section_t *sec = xmalloc(sizeof(struct elf_section_t));
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if(params->first_section == NULL)
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params->first_section = params->last_section = sec;
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else
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{
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params->last_section->next = sec;
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params->last_section = sec;
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}
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sec->next = NULL;
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return sec;
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}
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static struct elf_segment_t *elf_add_segment(struct elf_params_t *params)
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{
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struct elf_segment_t *seg = xmalloc(sizeof(struct elf_section_t));
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if(params->first_segment == NULL)
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params->first_segment = params->last_segment = seg;
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else
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{
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params->last_segment->next = seg;
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params->last_segment = seg;
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}
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seg->next = NULL;
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return seg;
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}
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void elf_add_load_section(struct elf_params_t *params,
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uint32_t load_addr, uint32_t size, const void *section, const char *name)
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{
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struct elf_section_t *sec = elf_add_section(params);
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sec->name = strdup(name);
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sec->type = EST_LOAD;
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sec->addr = load_addr;
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sec->size = size;
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sec->section = xmalloc(size);
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memcpy(sec->section, section, size);
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}
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void elf_add_fill_section(struct elf_params_t *params,
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uint32_t fill_addr, uint32_t size, uint32_t pattern, const char *name)
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{
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if(pattern != 0x00)
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{
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printf("oops, non-zero filling, ignore fill section\n");
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return;
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}
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struct elf_section_t *sec = elf_add_section(params);
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sec->name = strdup(name);
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sec->type = EST_FILL;
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sec->addr = fill_addr;
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sec->size = size;
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sec->pattern = pattern;
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}
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/* sort by increasing type and then increasing address */
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static int elf_simplify_compare(const void *a, const void *b)
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{
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const struct elf_section_t *sa = a;
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const struct elf_section_t *sb = b;
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if(sa->type != sb->type)
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return sa->type - sb->type;
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return sa->addr - sb->addr;
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}
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void elf_simplify(struct elf_params_t *params)
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{
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/** find all sections of the same types which are contiguous and merge them */
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/* count sections */
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int nr_sections = 0;
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struct elf_section_t *cur_sec = params->first_section;
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while(cur_sec)
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{
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nr_sections++;
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cur_sec = cur_sec->next;
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}
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/* put all sections in an array and free list */
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struct elf_section_t *sections = malloc(sizeof(struct elf_section_t) * nr_sections);
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cur_sec = params->first_section;
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for(int i = 0; i < nr_sections; i++)
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{
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memcpy(§ions[i], cur_sec, sizeof(struct elf_section_t));
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struct elf_section_t *old = cur_sec;
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cur_sec = cur_sec->next;
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free(old);
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}
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/* sort them by type and increasing addresses */
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qsort(sections, nr_sections, sizeof(struct elf_section_t), &elf_simplify_compare);
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/* merge them ! */
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cur_sec = §ions[0];
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for(int i = 1; i < nr_sections; i++)
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{
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/* different type => no */
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if(sections[i].type != cur_sec->type)
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goto Lnext;
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/* (for fill) different pattern => no */
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if(sections[i].type == EST_FILL && sections[i].pattern != cur_sec->pattern)
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goto Lnext;
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/* not contiguous => no */
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if(sections[i].addr != cur_sec->addr + cur_sec->size)
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goto Lnext;
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/* merge !! */
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if(sections[i].type == EST_FILL)
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{
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cur_sec->size += sections[i].size;
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sections[i].size = 0; // will be ignored by rebuilding (see below)
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}
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else if(sections[i].type == EST_LOAD)
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{
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// merge data also
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void *data = malloc(cur_sec->size + sections[i].size);
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memcpy(data, cur_sec->section, cur_sec->size);
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memcpy(data + cur_sec->size, sections[i].section, sections[i].size);
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free(cur_sec->section);
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free(sections[i].section);
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free(sections[i].name);
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cur_sec->section = data;
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cur_sec->size += sections[i].size;
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sections[i].size = 0; // will be ignored by rebuilding (see below)
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}
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continue;
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/* update current section to consider */
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Lnext:
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cur_sec = §ions[i];
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}
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/* put back on a list and free array */
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struct elf_section_t **prev_ptr = ¶ms->first_section;
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struct elf_section_t *prev_sec = NULL;
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for(int i = 0; i < nr_sections; i++)
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{
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/* skip empty sections produced by simplification */
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if(sections[i].size == 0)
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continue;
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struct elf_section_t *sec = malloc(sizeof(struct elf_section_t));
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memcpy(sec, §ions[i], sizeof(struct elf_section_t));
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*prev_ptr = sec;
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prev_ptr = &sec->next;
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prev_sec = sec;
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}
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*prev_ptr = NULL;
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params->last_section = prev_sec;
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free(sections);
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}
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/* sort by increasing address */
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static int elf_addr_compare(const void *a, const void *b)
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{
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const struct elf_section_t *sa = a;
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const struct elf_section_t *sb = b;
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return sa->addr - sb->addr;
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}
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void elf_sort_by_address(struct elf_params_t *params)
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{
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/** sort sections by address */
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/* count sections */
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int nr_sections = 0;
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struct elf_section_t *cur_sec = params->first_section;
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while(cur_sec)
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{
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nr_sections++;
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cur_sec = cur_sec->next;
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}
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/* put all sections in an array and free list */
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struct elf_section_t *sections = malloc(sizeof(struct elf_section_t) * nr_sections);
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cur_sec = params->first_section;
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for(int i = 0; i < nr_sections; i++)
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{
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memcpy(§ions[i], cur_sec, sizeof(struct elf_section_t));
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struct elf_section_t *old = cur_sec;
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cur_sec = cur_sec->next;
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free(old);
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}
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/* sort them by type and increasing addresses */
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qsort(sections, nr_sections, sizeof(struct elf_section_t), &elf_addr_compare);
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/* put back on a list and free array */
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struct elf_section_t **prev_ptr = ¶ms->first_section;
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struct elf_section_t *prev_sec = NULL;
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for(int i = 0; i < nr_sections; i++)
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{
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/* skip empty sections produced by simplification */
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if(sections[i].size == 0)
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continue;
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struct elf_section_t *sec = malloc(sizeof(struct elf_section_t));
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memcpy(sec, §ions[i], sizeof(struct elf_section_t));
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*prev_ptr = sec;
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prev_ptr = &sec->next;
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prev_sec = sec;
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}
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*prev_ptr = NULL;
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params->last_section = prev_sec;
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free(sections);
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}
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void elf_write_file(struct elf_params_t *params, elf_write_fn_t write,
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elf_printf_fn_t printf, void *user)
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{
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(void) printf;
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Elf32_Ehdr ehdr;
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uint32_t phnum = 0;
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struct elf_section_t *sec = params->first_section;
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uint32_t offset = 0;
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Elf32_Phdr phdr;
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Elf32_Shdr shdr;
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memset(&ehdr, 0, EI_NIDENT);
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while(sec)
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{
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if(sec->type == EST_LOAD)
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{
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sec->offset = offset;
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offset += sec->size;
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}
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else
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{
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sec->offset = 0;
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}
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phnum++;
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sec = sec->next;
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}
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uint32_t strtbl_offset = offset;
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ehdr.e_ident[EI_MAG0] = ELFMAG0;
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ehdr.e_ident[EI_MAG1] = ELFMAG1;
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ehdr.e_ident[EI_MAG2] = ELFMAG2;
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ehdr.e_ident[EI_MAG3] = ELFMAG3;
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ehdr.e_ident[EI_CLASS] = ELFCLASS32;
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ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
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ehdr.e_ident[EI_VERSION] = EV_CURRENT;
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ehdr.e_ident[EI_OSABI] = ELFOSABI_NONE;
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ehdr.e_ident[EI_ABIVERSION] = 0;
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ehdr.e_type = ET_EXEC;
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ehdr.e_machine = EM_ARM;
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ehdr.e_version = EV_CURRENT;
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ehdr.e_entry = params->start_addr;
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ehdr.e_flags = 0;
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if(params->has_start_addr)
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ehdr.e_flags |= EF_ARM_HASENTRY;
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ehdr.e_ehsize = sizeof ehdr;
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ehdr.e_phentsize = sizeof phdr;
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ehdr.e_phnum = phnum;
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ehdr.e_shentsize = sizeof shdr;
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ehdr.e_shnum = phnum + 2; /* one for section 0 and one for string table */
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ehdr.e_shstrndx = ehdr.e_shnum - 1;
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ehdr.e_phoff = ehdr.e_ehsize;
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ehdr.e_shoff = ehdr.e_ehsize + ehdr.e_phnum * ehdr.e_phentsize;
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write(user, 0, &ehdr, sizeof ehdr);
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/* allocate enough size for the string table:
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* - one empty name ("\0")
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* - one name ".shstrtab\0"
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* - all section names with zeroes */
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size_t strtbl_size = 1+ strlen(".shstrtab") + 1;
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sec = params->first_section;
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while(sec)
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{
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strtbl_size += strlen(sec->name) + 1;
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sec = sec->next;
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}
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char *strtbl_content = malloc(strtbl_size);
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strtbl_content[0] = '\0';
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strcpy(&strtbl_content[1], ".shstrtab");
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uint32_t strtbl_index = 1 + strlen(".shstrtab") + 1;
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uint32_t data_offset = ehdr.e_ehsize + ehdr.e_phnum * ehdr.e_phentsize +
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ehdr.e_shnum * ehdr.e_shentsize;
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sec = params->first_section;
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offset = ehdr.e_phoff;
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while(sec)
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{
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sec->offset += data_offset;
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phdr.p_type = PT_LOAD;
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if(sec->type == EST_LOAD)
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phdr.p_offset = sec->offset;
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else
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phdr.p_offset = 0;
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phdr.p_paddr = sec->addr;
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phdr.p_vaddr = phdr.p_paddr; /* assume identity map ? */
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phdr.p_memsz = sec->size;
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if(sec->type == EST_LOAD)
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phdr.p_filesz = phdr.p_memsz;
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else
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phdr.p_filesz = 0;
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phdr.p_flags = PF_X | PF_W | PF_R;
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phdr.p_align = 0;
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write(user, offset, &phdr, sizeof phdr);
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offset += sizeof(Elf32_Phdr);
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sec = sec->next;
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}
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sec = params->first_section;
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offset = ehdr.e_shoff;
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|
|
{
|
|
shdr.sh_name = 0;
|
|
shdr.sh_type = SHT_NULL;
|
|
shdr.sh_flags = 0;
|
|
shdr.sh_addr = 0;
|
|
shdr.sh_offset = 0;
|
|
shdr.sh_size = 0;
|
|
shdr.sh_link = SHN_UNDEF;
|
|
shdr.sh_info = 0;
|
|
shdr.sh_addralign = 0;
|
|
shdr.sh_entsize = 0;
|
|
|
|
write(user, offset, &shdr, sizeof shdr);
|
|
|
|
offset += sizeof(Elf32_Shdr);
|
|
}
|
|
|
|
while(sec)
|
|
{
|
|
shdr.sh_name = strtbl_index;
|
|
strtbl_index += 1 + sprintf(&strtbl_content[strtbl_index], "%s", sec->name);
|
|
if(sec->type == EST_LOAD)
|
|
shdr.sh_type = SHT_PROGBITS;
|
|
else
|
|
shdr.sh_type = SHT_NOBITS;
|
|
shdr.sh_flags = SHF_ALLOC | SHF_EXECINSTR;
|
|
shdr.sh_addr = sec->addr;
|
|
shdr.sh_offset = sec->offset;
|
|
shdr.sh_size = sec->size;
|
|
shdr.sh_link = SHN_UNDEF;
|
|
shdr.sh_info = 0;
|
|
shdr.sh_addralign = 1;
|
|
shdr.sh_entsize = 0;
|
|
|
|
write(user, offset, &shdr, sizeof shdr);
|
|
|
|
offset += sizeof(Elf32_Shdr);
|
|
sec = sec->next;
|
|
}
|
|
|
|
{
|
|
shdr.sh_name = 1;
|
|
shdr.sh_type = SHT_STRTAB;
|
|
shdr.sh_flags = 0;
|
|
shdr.sh_addr = 0;
|
|
shdr.sh_offset = strtbl_offset + data_offset;
|
|
shdr.sh_size = strtbl_index;
|
|
shdr.sh_link = SHN_UNDEF;
|
|
shdr.sh_info = 0;
|
|
shdr.sh_addralign = 1;
|
|
shdr.sh_entsize = 0;
|
|
|
|
write(user, offset, &shdr, sizeof shdr);
|
|
|
|
offset += sizeof(Elf32_Shdr);
|
|
}
|
|
|
|
sec = params->first_section;
|
|
while(sec)
|
|
{
|
|
if(sec->type == EST_LOAD)
|
|
write(user, sec->offset, sec->section, sec->size);
|
|
sec = sec->next;
|
|
}
|
|
|
|
write(user, strtbl_offset + data_offset, strtbl_content, strtbl_index);
|
|
free(strtbl_content);
|
|
}
|
|
|
|
bool elf_guess(elf_read_fn_t read, void *user)
|
|
{
|
|
/* read header */
|
|
Elf32_Ehdr ehdr;
|
|
if(!read(user, 0, &ehdr, sizeof(ehdr)))
|
|
return false;
|
|
/* basic checks */
|
|
return ehdr.e_ident[EI_MAG0] == ELFMAG0 && ehdr.e_ident[EI_MAG1] == ELFMAG1 &&
|
|
ehdr.e_ident[EI_MAG2] == ELFMAG2 && ehdr.e_ident[EI_MAG3] == ELFMAG3 &&
|
|
ehdr.e_ehsize == sizeof(ehdr) && ehdr.e_phentsize == sizeof(Elf32_Phdr) &&
|
|
ehdr.e_shentsize == sizeof(Elf32_Shdr);
|
|
}
|
|
|
|
bool elf_read_file(struct elf_params_t *params, elf_read_fn_t read,
|
|
elf_printf_fn_t printf, void *user)
|
|
{
|
|
#define error_printf(...) ({printf(user, true, __VA_ARGS__); return false;})
|
|
|
|
/* read header */
|
|
Elf32_Ehdr ehdr;
|
|
if(!read(user, 0, &ehdr, sizeof(ehdr)))
|
|
{
|
|
printf(user, true, "error reading elf header\n");
|
|
return false;
|
|
}
|
|
/* basic checks */
|
|
if(ehdr.e_ident[EI_MAG0] != ELFMAG0 || ehdr.e_ident[EI_MAG1] != ELFMAG1 ||
|
|
ehdr.e_ident[EI_MAG2] != ELFMAG2 || ehdr.e_ident[EI_MAG3] != ELFMAG3)
|
|
error_printf("invalid elf header\n");
|
|
if(ehdr.e_ident[EI_CLASS] != ELFCLASS32)
|
|
error_printf("invalid elf class: must be a 32-bit object\n");
|
|
if(ehdr.e_ident[EI_DATA] != ELFDATA2LSB)
|
|
error_printf("invalid elf data encoding: must be 32-bit lsb\n");
|
|
if(ehdr.e_ident[EI_VERSION] != EV_CURRENT)
|
|
error_printf("invalid elf version\n");
|
|
if(ehdr.e_type != ET_EXEC)
|
|
error_printf("invalid elf file: must be an executable file\n");
|
|
if(ehdr.e_machine != EM_ARM)
|
|
error_printf("invalid elf file: must target an arm machine\n");
|
|
if(ehdr.e_ehsize != sizeof(ehdr))
|
|
error_printf("invalid elf file: size header mismatch\n");
|
|
if(ehdr.e_phnum > 0 && ehdr.e_phentsize != sizeof(Elf32_Phdr))
|
|
error_printf("invalid elf file: program header size mismatch\n");
|
|
if(ehdr.e_shnum > 0 && ehdr.e_shentsize != sizeof(Elf32_Shdr))
|
|
error_printf("invalid elf file: section header size mismatch\n");
|
|
elf_set_start_addr(params, ehdr.e_entry);
|
|
|
|
char *strtab = NULL;
|
|
if(ehdr.e_shstrndx != SHN_UNDEF)
|
|
{
|
|
Elf32_Shdr shstrtab;
|
|
if(read(user, ehdr.e_shoff + ehdr.e_shstrndx * ehdr.e_shentsize,
|
|
&shstrtab, sizeof(shstrtab)))
|
|
{
|
|
strtab = xmalloc(shstrtab.sh_size);
|
|
if(!read(user, shstrtab.sh_offset, strtab, shstrtab.sh_size))
|
|
{
|
|
free(strtab);
|
|
strtab = NULL;
|
|
}
|
|
}
|
|
}
|
|
/* run through sections */
|
|
printf(user, false, "ELF file:\n");
|
|
for(int i = 1; i < ehdr.e_shnum; i++)
|
|
{
|
|
uint32_t off = ehdr.e_shoff + i * ehdr.e_shentsize;
|
|
Elf32_Shdr shdr;
|
|
memset(&shdr, 0, sizeof(shdr));
|
|
if(!read(user, off, &shdr, sizeof(shdr)))
|
|
error_printf("error reading elf section header");
|
|
|
|
if(shdr.sh_type == SHT_PROGBITS && shdr.sh_flags & SHF_ALLOC)
|
|
{
|
|
void *data = xmalloc(shdr.sh_size);
|
|
if(!read(user, shdr.sh_offset, data, shdr.sh_size))
|
|
error_printf("error read self section data\n");
|
|
elf_add_load_section(params, shdr.sh_addr, shdr.sh_size, data, &strtab[shdr.sh_name]);
|
|
free(data);
|
|
|
|
if(strtab)
|
|
printf(user, false, "create load segment for %s\n", &strtab[shdr.sh_name]);
|
|
}
|
|
else if(shdr.sh_type == SHT_NOBITS && shdr.sh_flags & SHF_ALLOC)
|
|
{
|
|
elf_add_fill_section(params, shdr.sh_addr, shdr.sh_size, 0, &strtab[shdr.sh_name]);
|
|
if(strtab)
|
|
printf(user, false, "create fill segment for %s\n", &strtab[shdr.sh_name]);
|
|
}
|
|
else
|
|
{
|
|
if(strtab)
|
|
printf(user, false, "filter out %s\n", &strtab[shdr.sh_name], shdr.sh_type);
|
|
}
|
|
|
|
}
|
|
free(strtab);
|
|
/* run through segments */
|
|
for(int i = 1; i < ehdr.e_phnum; i++)
|
|
{
|
|
uint32_t off = ehdr.e_phoff + i * ehdr.e_phentsize;
|
|
Elf32_Phdr phdr;
|
|
memset(&phdr, 0, sizeof(phdr));
|
|
if(!read(user, off, &phdr, sizeof(phdr)))
|
|
error_printf("error reading elf segment header");
|
|
if(phdr.p_type != PT_LOAD)
|
|
continue;
|
|
struct elf_segment_t *seg = elf_add_segment(params);
|
|
seg->vaddr = phdr.p_vaddr;
|
|
seg->paddr = phdr.p_paddr;
|
|
seg->vsize = phdr.p_memsz;
|
|
seg->psize = phdr.p_filesz;
|
|
printf(user, false, "create segment [%#x,+%#x[ -> [%#x,+%#x[\n",
|
|
seg->vaddr, seg->vsize, seg->paddr, seg->psize);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
uint32_t elf_translate_virtual_address(struct elf_params_t *params, uint32_t addr)
|
|
{
|
|
struct elf_segment_t *seg = params->first_segment;
|
|
while(seg)
|
|
{
|
|
if(seg->vaddr <= addr && addr < seg->vaddr + seg->vsize)
|
|
return addr - seg->vaddr + seg->paddr;
|
|
seg = seg->next;
|
|
}
|
|
return addr;
|
|
}
|
|
|
|
void elf_translate_addresses(struct elf_params_t *params)
|
|
{
|
|
struct elf_section_t *sec = params->first_section;
|
|
while(sec)
|
|
{
|
|
sec->addr = elf_translate_virtual_address(params, sec->addr);
|
|
sec = sec->next;
|
|
}
|
|
params->start_addr = elf_translate_virtual_address(params, params->start_addr);
|
|
}
|
|
|
|
bool elf_is_empty(struct elf_params_t *params)
|
|
{
|
|
return params->first_section == NULL;
|
|
}
|
|
|
|
void elf_set_start_addr(struct elf_params_t *params, uint32_t addr)
|
|
{
|
|
params->has_start_addr = true;
|
|
params->start_addr = addr;
|
|
}
|
|
|
|
bool elf_get_start_addr(struct elf_params_t *params, uint32_t *addr)
|
|
{
|
|
if(params->has_start_addr && addr != NULL)
|
|
*addr = params->start_addr;
|
|
return params->has_start_addr;
|
|
}
|
|
|
|
int elf_get_nr_sections(struct elf_params_t *params)
|
|
{
|
|
int nr = 0;
|
|
struct elf_section_t *sec = params->first_section;
|
|
while(sec)
|
|
{
|
|
nr++;
|
|
sec = sec->next;
|
|
}
|
|
return nr;
|
|
}
|
|
|
|
void elf_release(struct elf_params_t *params)
|
|
{
|
|
struct elf_section_t *sec = params->first_section;
|
|
while(sec)
|
|
{
|
|
struct elf_section_t *next_sec = sec->next;
|
|
if(sec->type == EST_LOAD)
|
|
free(sec->section);
|
|
free(sec->name);
|
|
free(sec);
|
|
sec = next_sec;
|
|
}
|
|
struct elf_segment_t *seg = params->first_segment;
|
|
while(seg)
|
|
{
|
|
struct elf_segment_t *next_seg = seg->next;
|
|
free(seg);
|
|
seg = next_seg;
|
|
}
|
|
}
|
|
|
|
void elf_std_printf(void *user, bool error, const char *fmt, ...)
|
|
{
|
|
if(!g_debug && !error)
|
|
return;
|
|
(void) user;
|
|
va_list args;
|
|
va_start(args, fmt);
|
|
vprintf(fmt, args);
|
|
va_end(args);
|
|
}
|
|
|
|
void elf_std_write(void *user, uint32_t addr, const void *buf, size_t count)
|
|
{
|
|
FILE *f = user;
|
|
fseek(f, addr, SEEK_SET);
|
|
fwrite(buf, count, 1, f);
|
|
}
|
|
|
|
bool elf_std_read(void *user, uint32_t addr, void *buf, size_t count)
|
|
{
|
|
if(fseek((FILE *)user, addr, SEEK_SET) == -1)
|
|
return false;
|
|
return fread(buf, 1, count, (FILE *)user) == count;
|
|
}
|