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authorAmaury Pouly <amaury.pouly@gmail.com>2012-05-23 11:03:35 +0200
committerAmaury Pouly <amaury.pouly@gmail.com>2012-05-31 13:57:25 +0200
commita87a9ef37372b4380808ec2efa7c762e137668f1 (patch)
tree9c759088f0f9cf6717d96789b6805812f6b187ea /utils/imxtools/sbtools/elf.c
parentba8e4367fb4d116ffc01c12cc619bfc714e582c9 (diff)
imxtools: move tools to a new sbtools/ subdirectory
Change-Id: I0d8d6831b35037725486f61fc363de87bc8ba92e
Diffstat (limited to 'utils/imxtools/sbtools/elf.c')
-rw-r--r--utils/imxtools/sbtools/elf.c575
1 files changed, 575 insertions, 0 deletions
diff --git a/utils/imxtools/sbtools/elf.c b/utils/imxtools/sbtools/elf.c
new file mode 100644
index 0000000000..481ab98dd6
--- /dev/null
+++ b/utils/imxtools/sbtools/elf.c
@@ -0,0 +1,575 @@
+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (C) 2011 Amaury Pouly
+ *
+ * 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 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include "elf.h"
+#include "misc.h"
+
+/**
+ * Definitions
+ * taken from elf.h linux header
+ * based on ELF specification
+ * based on ARM ELF specification
+ */
+typedef uint16_t Elf32_Half;
+
+typedef uint32_t Elf32_Word;
+typedef int32_t Elf32_Sword;
+typedef uint32_t Elf32_Addr;
+typedef uint32_t Elf32_Off;
+typedef uint16_t Elf32_Section;
+
+#define EI_NIDENT 16
+
+typedef struct
+{
+ unsigned char e_ident[EI_NIDENT]; /* Magic number and other info */
+ Elf32_Half e_type; /* Object file type */
+ Elf32_Half e_machine; /* Architecture */
+ Elf32_Word e_version; /* Object file version */
+ Elf32_Addr e_entry; /* Entry point virtual address */
+ Elf32_Off e_phoff; /* Program header table file offset */
+ Elf32_Off e_shoff; /* Section header table file offset */
+ Elf32_Word e_flags; /* Processor-specific flags */
+ Elf32_Half e_ehsize; /* ELF header size in bytes */
+ Elf32_Half e_phentsize; /* Program header table entry size */
+ Elf32_Half e_phnum; /* Program header table entry count */
+ Elf32_Half e_shentsize; /* Section header table entry size */
+ Elf32_Half e_shnum; /* Section header table entry count */
+ Elf32_Half e_shstrndx; /* Section header string table index */
+}Elf32_Ehdr;
+
+#define EI_MAG0 0 /* File identification byte 0 index */
+#define ELFMAG0 0x7f /* Magic number byte 0 */
+
+#define EI_MAG1 1 /* File identification byte 1 index */
+#define ELFMAG1 'E' /* Magic number byte 1 */
+
+#define EI_MAG2 2 /* File identification byte 2 index */
+#define ELFMAG2 'L' /* Magic number byte 2 */
+
+#define EI_MAG3 3 /* File identification byte 3 index */
+#define ELFMAG3 'F' /* Magic number byte 3 */
+
+#define EI_CLASS 4 /* File class byte index */
+#define ELFCLASS32 1 /* 32-bit objects */
+
+#define EI_DATA 5 /* Data encoding byte index */
+#define ELFDATA2LSB 1 /* 2's complement, little endian */
+
+#define EI_VERSION 6 /* File version byte index, Value must be EV_CURRENT */
+
+#define EI_OSABI 7 /* OS ABI identification */
+#define ELFOSABI_NONE 0 /* UNIX System V ABI */
+#define ELFOSABI_ARM_AEABI 64 /* ARM EABI */
+#define ELFOSABI_ARM 97 /* ARM */
+
+#define EI_ABIVERSION 8 /* ABI version */
+
+#define EI_PAD 9 /* Byte index of padding bytes */
+
+#define ET_EXEC 2 /* Executable file */
+
+#define EM_ARM 40 /* ARM */
+
+#define EV_CURRENT 1 /* Current version */
+
+#define EF_ARM_HASENTRY 0x00000002
+
+#define SHN_UNDEF 0 /* Undefined section */
+
+typedef struct
+{
+ Elf32_Word sh_name; /* Section name (string tbl index) */
+ Elf32_Word sh_type; /* Section type */
+ Elf32_Word sh_flags; /* Section flags */
+ Elf32_Addr sh_addr; /* Section virtual addr at execution */
+ Elf32_Off sh_offset; /* Section file offset */
+ Elf32_Word sh_size; /* Section size in bytes */
+ Elf32_Word sh_link; /* Link to another section */
+ Elf32_Word sh_info; /* Additional section information */
+ Elf32_Word sh_addralign; /* Section alignment */
+ Elf32_Word sh_entsize; /* Entry size if section holds table */
+}Elf32_Shdr;
+
+#define SHT_NULL 0 /* Section header table entry unused */
+#define SHT_PROGBITS 1 /* Program data */
+#define SHT_SYMTAB 2 /* Symbol table */
+#define SHT_STRTAB 3 /* String table */
+#define SHT_RELA 4 /* Relocation entries with addends */
+#define SHT_HASH 5 /* Symbol hash table */
+#define SHT_DYNAMIC 6 /* Dynamic linking information */
+#define SHT_NOTE 7 /* Notes */
+#define SHT_NOBITS 8 /* Program space with no data (bss) */
+#define SHT_REL 9 /* Relocation entries, no addends */
+#define SHT_SHLIB 10 /* Reserved */
+#define SHT_DYNSYM 11 /* Dynamic linker symbol table */
+#define SHT_INIT_ARRAY 14 /* Array of constructors */
+#define SHT_FINI_ARRAY 15 /* Array of destructors */
+#define SHT_PREINIT_ARRAY 16 /* Array of pre-constructors */
+#define SHT_GROUP 17 /* Section group */
+#define SHT_SYMTAB_SHNDX 18 /* Extended section indeces */
+#define SHT_NUM 19 /* Number of defined types. */
+
+#define SHF_WRITE (1 << 0) /* Writable */
+#define SHF_ALLOC (1 << 1) /* Occupies memory during execution */
+#define SHF_EXECINSTR (1 << 2) /* Executable */
+#define SHF_MERGE (1 << 4) /* Might be merged */
+#define SHF_STRINGS (1 << 5) /* Contains nul-terminated strings */
+
+typedef struct
+{
+ Elf32_Word p_type; /* Segment type */
+ Elf32_Off p_offset; /* Segment file offset */
+ Elf32_Addr p_vaddr; /* Segment virtual address */
+ Elf32_Addr p_paddr; /* Segment physical address */
+ Elf32_Word p_filesz; /* Segment size in file */
+ Elf32_Word p_memsz; /* Segment size in memory */
+ Elf32_Word p_flags; /* Segment flags */
+ Elf32_Word p_align; /* Segment alignment */
+}Elf32_Phdr;
+
+#define PT_LOAD 1 /* Loadable program segment */
+
+#define PF_X (1 << 0) /* Segment is executable */
+#define PF_W (1 << 1) /* Segment is writable */
+#define PF_R (1 << 2) /* Segment is readable */
+
+void elf_init(struct elf_params_t *params)
+{
+ memset(params, 0, sizeof(struct elf_params_t));
+}
+
+extern void *xmalloc(size_t s);
+
+static struct elf_section_t *elf_add_section(struct elf_params_t *params)
+{
+ struct elf_section_t *sec = xmalloc(sizeof(struct elf_section_t));
+ if(params->first_section == NULL)
+ params->first_section = params->last_section = sec;
+ else
+ {
+ params->last_section->next = sec;
+ params->last_section = sec;
+ }
+ sec->next = NULL;
+
+ return sec;
+}
+
+static struct elf_segment_t *elf_add_segment(struct elf_params_t *params)
+{
+ struct elf_segment_t *seg = xmalloc(sizeof(struct elf_section_t));
+ if(params->first_segment == NULL)
+ params->first_segment = params->last_segment = seg;
+ else
+ {
+ params->last_segment->next = seg;
+ params->last_segment = seg;
+ }
+ seg->next = NULL;
+
+ return seg;
+}
+
+void elf_add_load_section(struct elf_params_t *params,
+ uint32_t load_addr, uint32_t size, const void *section)
+{
+ struct elf_section_t *sec = elf_add_section(params);
+
+ sec->type = EST_LOAD;
+ sec->addr = load_addr;
+ sec->size = size;
+ sec->section = xmalloc(size);
+ memcpy(sec->section, section, size);
+}
+
+void elf_add_fill_section(struct elf_params_t *params,
+ uint32_t fill_addr, uint32_t size, uint32_t pattern)
+{
+ if(pattern != 0x00)
+ {
+ printf("oops, non-zero filling, ignore fill section\n");
+ return;
+ }
+
+ struct elf_section_t *sec = elf_add_section(params);
+
+ sec->type = EST_FILL;
+ sec->addr = fill_addr;
+ sec->size = size;
+ sec->pattern = pattern;
+}
+
+void elf_write_file(struct elf_params_t *params, elf_write_fn_t write,
+ elf_printf_fn_t printf, void *user)
+{
+ (void) printf;
+
+ Elf32_Ehdr ehdr;
+ uint32_t phnum = 0;
+ struct elf_section_t *sec = params->first_section;
+ uint32_t offset = 0;
+ Elf32_Phdr phdr;
+ Elf32_Shdr shdr;
+ memset(&ehdr, 0, EI_NIDENT);
+
+ while(sec)
+ {
+ if(sec->type == EST_LOAD)
+ {
+ sec->offset = offset;
+ offset += sec->size;
+ }
+ else
+ {
+ sec->offset = 0;
+ }
+
+ phnum++;
+ sec = sec->next;
+ }
+
+ uint32_t strtbl_offset = offset;
+
+ 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_ident[EI_CLASS] = ELFCLASS32;
+ ehdr.e_ident[EI_DATA] = ELFDATA2LSB;
+ ehdr.e_ident[EI_VERSION] = EV_CURRENT;
+ ehdr.e_ident[EI_OSABI] = ELFOSABI_NONE;
+ ehdr.e_ident[EI_ABIVERSION] = 0;
+ ehdr.e_type = ET_EXEC;
+ ehdr.e_machine = EM_ARM;
+ ehdr.e_version = EV_CURRENT;
+ ehdr.e_entry = params->start_addr;
+ ehdr.e_flags = 0;
+ if(params->has_start_addr)
+ ehdr.e_flags |= EF_ARM_HASENTRY;
+ ehdr.e_ehsize = sizeof ehdr;
+ ehdr.e_phentsize = sizeof phdr;
+ ehdr.e_phnum = phnum;
+ ehdr.e_shentsize = sizeof shdr;
+ ehdr.e_shnum = phnum + 2; /* one for section 0 and one for string table */
+ ehdr.e_shstrndx = ehdr.e_shnum - 1;
+ ehdr.e_phoff = ehdr.e_ehsize;
+ ehdr.e_shoff = ehdr.e_ehsize + ehdr.e_phnum * ehdr.e_phentsize;
+
+ write(user, 0, &ehdr, sizeof ehdr);
+
+ /* allocate enough size to hold any combinaison of .text/.bss in the string table:
+ * - one empty name ("\0")
+ * - at most N names of the form ".textXXXX\0" or ".bssXXXX\0"
+ * - one name ".shstrtab\0" */
+ char *strtbl_content = malloc(1 + strlen(".shstrtab") + 1 +
+ phnum * (strlen(".textXXXX") + 1));
+
+ strtbl_content[0] = '\0';
+ strcpy(&strtbl_content[1], ".shstrtab");
+ uint32_t strtbl_index = 1 + strlen(".shstrtab") + 1;
+
+ uint32_t data_offset = ehdr.e_ehsize + ehdr.e_phnum * ehdr.e_phentsize +
+ ehdr.e_shnum * ehdr.e_shentsize;
+
+ sec = params->first_section;
+ offset = ehdr.e_phoff;
+ while(sec)
+ {
+ sec->offset += data_offset;
+
+ phdr.p_type = PT_LOAD;
+ if(sec->type == EST_LOAD)
+ phdr.p_offset = sec->offset;
+ else
+ phdr.p_offset = 0;
+ phdr.p_paddr = sec->addr;
+ phdr.p_vaddr = phdr.p_paddr; /* assume identity map ? */
+ phdr.p_memsz = sec->size;
+ if(sec->type == EST_LOAD)
+ phdr.p_filesz = phdr.p_memsz;
+ else
+ phdr.p_filesz = 0;
+ phdr.p_flags = PF_X | PF_W | PF_R;
+ phdr.p_align = 0;
+
+ write(user, offset, &phdr, sizeof phdr);
+
+ offset += sizeof(Elf32_Phdr);
+ sec = sec->next;
+ }
+
+ sec = params->first_section;
+ offset = ehdr.e_shoff;
+
+ {
+ 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);
+ }
+
+ uint32_t text_idx = 0;
+ uint32_t bss_idx = 0;
+ while(sec)
+ {
+ shdr.sh_name = strtbl_index;
+ if(sec->type == EST_LOAD)
+ {
+ strtbl_index += 1 + sprintf(&strtbl_content[strtbl_index], ".text%d", text_idx++);
+ shdr.sh_type = SHT_PROGBITS;
+ }
+ else
+ {
+ strtbl_index += 1 + sprintf(&strtbl_content[strtbl_index], ".bss%d", bss_idx++);
+ 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_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);
+ 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);
+ 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);
+ 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;
+ }
+}