652 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			652 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <stdio.h>
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| #include <stdarg.h>
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| #include <stdlib.h>
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| #include <stdint.h>
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| #include <string.h>
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| #include <errno.h>
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| #include <unistd.h>
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| #include <elf.h>
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| #include <byteswap.h>
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| #define USE_BSD
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| #include <endian.h>
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| 
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| #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
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| static Elf32_Ehdr ehdr;
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| static unsigned long reloc_count, reloc_idx;
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| static unsigned long *relocs;
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| 
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| struct section {
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| 	Elf32_Shdr     shdr;
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| 	struct section *link;
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| 	Elf32_Sym      *symtab;
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| 	Elf32_Rel      *reltab;
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| 	char           *strtab;
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| };
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| static struct section *secs;
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| 
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| /*
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|  * Following symbols have been audited. There values are constant and do
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|  * not change if bzImage is loaded at a different physical address than
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|  * the address for which it has been compiled. Don't warn user about
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|  * absolute relocations present w.r.t these symbols.
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|  */
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| static const char* safe_abs_relocs[] = {
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| 		"xen_irq_disable_direct_reloc",
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| 		"xen_save_fl_direct_reloc",
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| };
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| 
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| static int is_safe_abs_reloc(const char* sym_name)
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| {
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| 	int i;
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| 
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| 	for (i = 0; i < ARRAY_SIZE(safe_abs_relocs); i++) {
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| 		if (!strcmp(sym_name, safe_abs_relocs[i]))
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| 			/* Match found */
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| 			return 1;
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| 	}
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| 	if (strncmp(sym_name, "VDSO", 4) == 0)
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| 		return 1;
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| 	if (strncmp(sym_name, "__crc_", 6) == 0)
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| 		return 1;
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| 	return 0;
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| }
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| 
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| static void die(char *fmt, ...)
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| {
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| 	va_list ap;
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| 	va_start(ap, fmt);
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| 	vfprintf(stderr, fmt, ap);
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| 	va_end(ap);
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| 	exit(1);
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| }
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| 
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| static const char *sym_type(unsigned type)
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| {
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| 	static const char *type_name[] = {
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| #define SYM_TYPE(X) [X] = #X
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| 		SYM_TYPE(STT_NOTYPE),
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| 		SYM_TYPE(STT_OBJECT),
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| 		SYM_TYPE(STT_FUNC),
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| 		SYM_TYPE(STT_SECTION),
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| 		SYM_TYPE(STT_FILE),
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| 		SYM_TYPE(STT_COMMON),
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| 		SYM_TYPE(STT_TLS),
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| #undef SYM_TYPE
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| 	};
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| 	const char *name = "unknown sym type name";
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| 	if (type < ARRAY_SIZE(type_name)) {
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| 		name = type_name[type];
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| 	}
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| 	return name;
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| }
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| 
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| static const char *sym_bind(unsigned bind)
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| {
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| 	static const char *bind_name[] = {
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| #define SYM_BIND(X) [X] = #X
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| 		SYM_BIND(STB_LOCAL),
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| 		SYM_BIND(STB_GLOBAL),
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| 		SYM_BIND(STB_WEAK),
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| #undef SYM_BIND
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| 	};
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| 	const char *name = "unknown sym bind name";
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| 	if (bind < ARRAY_SIZE(bind_name)) {
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| 		name = bind_name[bind];
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| 	}
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| 	return name;
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| }
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| 
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| static const char *sym_visibility(unsigned visibility)
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| {
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| 	static const char *visibility_name[] = {
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| #define SYM_VISIBILITY(X) [X] = #X
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| 		SYM_VISIBILITY(STV_DEFAULT),
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| 		SYM_VISIBILITY(STV_INTERNAL),
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| 		SYM_VISIBILITY(STV_HIDDEN),
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| 		SYM_VISIBILITY(STV_PROTECTED),
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| #undef SYM_VISIBILITY
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| 	};
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| 	const char *name = "unknown sym visibility name";
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| 	if (visibility < ARRAY_SIZE(visibility_name)) {
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| 		name = visibility_name[visibility];
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| 	}
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| 	return name;
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| }
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| 
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| static const char *rel_type(unsigned type)
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| {
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| 	static const char *type_name[] = {
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| #define REL_TYPE(X) [X] = #X
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| 		REL_TYPE(R_386_NONE),
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| 		REL_TYPE(R_386_32),
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| 		REL_TYPE(R_386_PC32),
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| 		REL_TYPE(R_386_GOT32),
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| 		REL_TYPE(R_386_PLT32),
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| 		REL_TYPE(R_386_COPY),
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| 		REL_TYPE(R_386_GLOB_DAT),
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| 		REL_TYPE(R_386_JMP_SLOT),
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| 		REL_TYPE(R_386_RELATIVE),
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| 		REL_TYPE(R_386_GOTOFF),
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| 		REL_TYPE(R_386_GOTPC),
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| #undef REL_TYPE
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| 	};
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| 	const char *name = "unknown type rel type name";
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| 	if (type < ARRAY_SIZE(type_name)) {
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| 		name = type_name[type];
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| 	}
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| 	return name;
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| }
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| 
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| static const char *sec_name(unsigned shndx)
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| {
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| 	const char *sec_strtab;
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| 	const char *name;
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| 	sec_strtab = secs[ehdr.e_shstrndx].strtab;
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| 	name = "<noname>";
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| 	if (shndx < ehdr.e_shnum) {
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| 		name = sec_strtab + secs[shndx].shdr.sh_name;
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| 	}
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| 	else if (shndx == SHN_ABS) {
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| 		name = "ABSOLUTE";
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| 	}
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| 	else if (shndx == SHN_COMMON) {
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| 		name = "COMMON";
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| 	}
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| 	return name;
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| }
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| 
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| static const char *sym_name(const char *sym_strtab, Elf32_Sym *sym)
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| {
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| 	const char *name;
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| 	name = "<noname>";
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| 	if (sym->st_name) {
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| 		name = sym_strtab + sym->st_name;
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| 	}
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| 	else {
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| 		name = sec_name(secs[sym->st_shndx].shdr.sh_name);
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| 	}
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| 	return name;
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| }
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| 
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| 
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| 
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| #if BYTE_ORDER == LITTLE_ENDIAN
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| #define le16_to_cpu(val) (val)
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| #define le32_to_cpu(val) (val)
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| #endif
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| #if BYTE_ORDER == BIG_ENDIAN
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| #define le16_to_cpu(val) bswap_16(val)
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| #define le32_to_cpu(val) bswap_32(val)
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| #endif
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| 
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| static uint16_t elf16_to_cpu(uint16_t val)
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| {
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| 	return le16_to_cpu(val);
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| }
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| 
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| static uint32_t elf32_to_cpu(uint32_t val)
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| {
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| 	return le32_to_cpu(val);
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| }
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| 
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| static void read_ehdr(FILE *fp)
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| {
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| 	if (fread(&ehdr, sizeof(ehdr), 1, fp) != 1) {
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| 		die("Cannot read ELF header: %s\n",
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| 			strerror(errno));
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| 	}
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| 	if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0) {
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| 		die("No ELF magic\n");
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| 	}
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| 	if (ehdr.e_ident[EI_CLASS] != ELFCLASS32) {
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| 		die("Not a 32 bit executable\n");
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| 	}
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| 	if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB) {
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| 		die("Not a LSB ELF executable\n");
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| 	}
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| 	if (ehdr.e_ident[EI_VERSION] != EV_CURRENT) {
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| 		die("Unknown ELF version\n");
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| 	}
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| 	/* Convert the fields to native endian */
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| 	ehdr.e_type      = elf16_to_cpu(ehdr.e_type);
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| 	ehdr.e_machine   = elf16_to_cpu(ehdr.e_machine);
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| 	ehdr.e_version   = elf32_to_cpu(ehdr.e_version);
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| 	ehdr.e_entry     = elf32_to_cpu(ehdr.e_entry);
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| 	ehdr.e_phoff     = elf32_to_cpu(ehdr.e_phoff);
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| 	ehdr.e_shoff     = elf32_to_cpu(ehdr.e_shoff);
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| 	ehdr.e_flags     = elf32_to_cpu(ehdr.e_flags);
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| 	ehdr.e_ehsize    = elf16_to_cpu(ehdr.e_ehsize);
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| 	ehdr.e_phentsize = elf16_to_cpu(ehdr.e_phentsize);
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| 	ehdr.e_phnum     = elf16_to_cpu(ehdr.e_phnum);
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| 	ehdr.e_shentsize = elf16_to_cpu(ehdr.e_shentsize);
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| 	ehdr.e_shnum     = elf16_to_cpu(ehdr.e_shnum);
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| 	ehdr.e_shstrndx  = elf16_to_cpu(ehdr.e_shstrndx);
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| 
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| 	if ((ehdr.e_type != ET_EXEC) && (ehdr.e_type != ET_DYN)) {
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| 		die("Unsupported ELF header type\n");
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| 	}
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| 	if (ehdr.e_machine != EM_386) {
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| 		die("Not for x86\n");
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| 	}
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| 	if (ehdr.e_version != EV_CURRENT) {
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| 		die("Unknown ELF version\n");
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| 	}
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| 	if (ehdr.e_ehsize != sizeof(Elf32_Ehdr)) {
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| 		die("Bad Elf header size\n");
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| 	}
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| 	if (ehdr.e_phentsize != sizeof(Elf32_Phdr)) {
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| 		die("Bad program header entry\n");
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| 	}
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| 	if (ehdr.e_shentsize != sizeof(Elf32_Shdr)) {
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| 		die("Bad section header entry\n");
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| 	}
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| 	if (ehdr.e_shstrndx >= ehdr.e_shnum) {
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| 		die("String table index out of bounds\n");
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| 	}
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| }
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| 
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| static void read_shdrs(FILE *fp)
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| {
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| 	int i;
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| 	Elf32_Shdr shdr;
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| 
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| 	secs = calloc(ehdr.e_shnum, sizeof(struct section));
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| 	if (!secs) {
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| 		die("Unable to allocate %d section headers\n",
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| 		    ehdr.e_shnum);
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| 	}
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| 	if (fseek(fp, ehdr.e_shoff, SEEK_SET) < 0) {
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| 		die("Seek to %d failed: %s\n",
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| 			ehdr.e_shoff, strerror(errno));
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| 	}
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| 	for (i = 0; i < ehdr.e_shnum; i++) {
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| 		struct section *sec = &secs[i];
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| 		if (fread(&shdr, sizeof shdr, 1, fp) != 1)
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| 			die("Cannot read ELF section headers %d/%d: %s\n",
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| 			    i, ehdr.e_shnum, strerror(errno));
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| 		sec->shdr.sh_name      = elf32_to_cpu(shdr.sh_name);
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| 		sec->shdr.sh_type      = elf32_to_cpu(shdr.sh_type);
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| 		sec->shdr.sh_flags     = elf32_to_cpu(shdr.sh_flags);
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| 		sec->shdr.sh_addr      = elf32_to_cpu(shdr.sh_addr);
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| 		sec->shdr.sh_offset    = elf32_to_cpu(shdr.sh_offset);
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| 		sec->shdr.sh_size      = elf32_to_cpu(shdr.sh_size);
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| 		sec->shdr.sh_link      = elf32_to_cpu(shdr.sh_link);
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| 		sec->shdr.sh_info      = elf32_to_cpu(shdr.sh_info);
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| 		sec->shdr.sh_addralign = elf32_to_cpu(shdr.sh_addralign);
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| 		sec->shdr.sh_entsize   = elf32_to_cpu(shdr.sh_entsize);
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| 		if (sec->shdr.sh_link < ehdr.e_shnum)
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| 			sec->link = &secs[sec->shdr.sh_link];
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| 	}
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| 
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| }
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| 
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| static void read_strtabs(FILE *fp)
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| {
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| 	int i;
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| 	for (i = 0; i < ehdr.e_shnum; i++) {
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| 		struct section *sec = &secs[i];
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| 		if (sec->shdr.sh_type != SHT_STRTAB) {
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| 			continue;
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| 		}
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| 		sec->strtab = malloc(sec->shdr.sh_size);
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| 		if (!sec->strtab) {
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| 			die("malloc of %d bytes for strtab failed\n",
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| 				sec->shdr.sh_size);
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| 		}
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| 		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
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| 			die("Seek to %d failed: %s\n",
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| 				sec->shdr.sh_offset, strerror(errno));
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| 		}
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| 		if (fread(sec->strtab, 1, sec->shdr.sh_size, fp)
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| 		    != sec->shdr.sh_size) {
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| 			die("Cannot read symbol table: %s\n",
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| 				strerror(errno));
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| 		}
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| 	}
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| }
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| 
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| static void read_symtabs(FILE *fp)
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| {
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| 	int i,j;
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| 	for (i = 0; i < ehdr.e_shnum; i++) {
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| 		struct section *sec = &secs[i];
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| 		if (sec->shdr.sh_type != SHT_SYMTAB) {
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| 			continue;
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| 		}
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| 		sec->symtab = malloc(sec->shdr.sh_size);
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| 		if (!sec->symtab) {
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| 			die("malloc of %d bytes for symtab failed\n",
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| 				sec->shdr.sh_size);
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| 		}
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| 		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
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| 			die("Seek to %d failed: %s\n",
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| 				sec->shdr.sh_offset, strerror(errno));
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| 		}
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| 		if (fread(sec->symtab, 1, sec->shdr.sh_size, fp)
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| 		    != sec->shdr.sh_size) {
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| 			die("Cannot read symbol table: %s\n",
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| 				strerror(errno));
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| 		}
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| 		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
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| 			Elf32_Sym *sym = &sec->symtab[j];
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| 			sym->st_name  = elf32_to_cpu(sym->st_name);
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| 			sym->st_value = elf32_to_cpu(sym->st_value);
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| 			sym->st_size  = elf32_to_cpu(sym->st_size);
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| 			sym->st_shndx = elf16_to_cpu(sym->st_shndx);
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| 		}
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| 	}
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| }
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| 
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| 
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| static void read_relocs(FILE *fp)
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| {
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| 	int i,j;
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| 	for (i = 0; i < ehdr.e_shnum; i++) {
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| 		struct section *sec = &secs[i];
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| 		if (sec->shdr.sh_type != SHT_REL) {
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| 			continue;
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| 		}
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| 		sec->reltab = malloc(sec->shdr.sh_size);
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| 		if (!sec->reltab) {
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| 			die("malloc of %d bytes for relocs failed\n",
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| 				sec->shdr.sh_size);
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| 		}
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| 		if (fseek(fp, sec->shdr.sh_offset, SEEK_SET) < 0) {
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| 			die("Seek to %d failed: %s\n",
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| 				sec->shdr.sh_offset, strerror(errno));
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| 		}
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| 		if (fread(sec->reltab, 1, sec->shdr.sh_size, fp)
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| 		    != sec->shdr.sh_size) {
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| 			die("Cannot read symbol table: %s\n",
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| 				strerror(errno));
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| 		}
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| 		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
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| 			Elf32_Rel *rel = &sec->reltab[j];
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| 			rel->r_offset = elf32_to_cpu(rel->r_offset);
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| 			rel->r_info   = elf32_to_cpu(rel->r_info);
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| 		}
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| 	}
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| }
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| 
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| 
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| static void print_absolute_symbols(void)
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| {
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| 	int i;
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| 	printf("Absolute symbols\n");
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| 	printf(" Num:    Value Size  Type       Bind        Visibility  Name\n");
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| 	for (i = 0; i < ehdr.e_shnum; i++) {
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| 		struct section *sec = &secs[i];
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| 		char *sym_strtab;
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| 		Elf32_Sym *sh_symtab;
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| 		int j;
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| 
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| 		if (sec->shdr.sh_type != SHT_SYMTAB) {
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| 			continue;
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| 		}
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| 		sh_symtab = sec->symtab;
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| 		sym_strtab = sec->link->strtab;
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| 		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Sym); j++) {
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| 			Elf32_Sym *sym;
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| 			const char *name;
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| 			sym = &sec->symtab[j];
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| 			name = sym_name(sym_strtab, sym);
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| 			if (sym->st_shndx != SHN_ABS) {
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| 				continue;
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| 			}
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| 			printf("%5d %08x %5d %10s %10s %12s %s\n",
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| 				j, sym->st_value, sym->st_size,
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| 				sym_type(ELF32_ST_TYPE(sym->st_info)),
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| 				sym_bind(ELF32_ST_BIND(sym->st_info)),
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| 				sym_visibility(ELF32_ST_VISIBILITY(sym->st_other)),
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| 				name);
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| 		}
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| 	}
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| 	printf("\n");
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| }
 | |
| 
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| static void print_absolute_relocs(void)
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| {
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| 	int i, printed = 0;
 | |
| 
 | |
| 	for (i = 0; i < ehdr.e_shnum; i++) {
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| 		struct section *sec = &secs[i];
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| 		struct section *sec_applies, *sec_symtab;
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| 		char *sym_strtab;
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| 		Elf32_Sym *sh_symtab;
 | |
| 		int j;
 | |
| 		if (sec->shdr.sh_type != SHT_REL) {
 | |
| 			continue;
 | |
| 		}
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| 		sec_symtab  = sec->link;
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| 		sec_applies = &secs[sec->shdr.sh_info];
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| 		if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
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| 			continue;
 | |
| 		}
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| 		sh_symtab  = sec_symtab->symtab;
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| 		sym_strtab = sec_symtab->link->strtab;
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| 		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
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| 			Elf32_Rel *rel;
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| 			Elf32_Sym *sym;
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| 			const char *name;
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| 			rel = &sec->reltab[j];
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| 			sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
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| 			name = sym_name(sym_strtab, sym);
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| 			if (sym->st_shndx != SHN_ABS) {
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| 				continue;
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| 			}
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| 
 | |
| 			/* Absolute symbols are not relocated if bzImage is
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| 			 * loaded at a non-compiled address. Display a warning
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| 			 * to user at compile time about the absolute
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| 			 * relocations present.
 | |
| 			 *
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| 			 * User need to audit the code to make sure
 | |
| 			 * some symbols which should have been section
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| 			 * relative have not become absolute because of some
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| 			 * linker optimization or wrong programming usage.
 | |
| 			 *
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| 			 * Before warning check if this absolute symbol
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| 			 * relocation is harmless.
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| 			 */
 | |
| 			if (is_safe_abs_reloc(name))
 | |
| 				continue;
 | |
| 
 | |
| 			if (!printed) {
 | |
| 				printf("WARNING: Absolute relocations"
 | |
| 					" present\n");
 | |
| 				printf("Offset     Info     Type     Sym.Value "
 | |
| 					"Sym.Name\n");
 | |
| 				printed = 1;
 | |
| 			}
 | |
| 
 | |
| 			printf("%08x %08x %10s %08x  %s\n",
 | |
| 				rel->r_offset,
 | |
| 				rel->r_info,
 | |
| 				rel_type(ELF32_R_TYPE(rel->r_info)),
 | |
| 				sym->st_value,
 | |
| 				name);
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	if (printed)
 | |
| 		printf("\n");
 | |
| }
 | |
| 
 | |
| static void walk_relocs(void (*visit)(Elf32_Rel *rel, Elf32_Sym *sym))
 | |
| {
 | |
| 	int i;
 | |
| 	/* Walk through the relocations */
 | |
| 	for (i = 0; i < ehdr.e_shnum; i++) {
 | |
| 		char *sym_strtab;
 | |
| 		Elf32_Sym *sh_symtab;
 | |
| 		struct section *sec_applies, *sec_symtab;
 | |
| 		int j;
 | |
| 		struct section *sec = &secs[i];
 | |
| 
 | |
| 		if (sec->shdr.sh_type != SHT_REL) {
 | |
| 			continue;
 | |
| 		}
 | |
| 		sec_symtab  = sec->link;
 | |
| 		sec_applies = &secs[sec->shdr.sh_info];
 | |
| 		if (!(sec_applies->shdr.sh_flags & SHF_ALLOC)) {
 | |
| 			continue;
 | |
| 		}
 | |
| 		sh_symtab = sec_symtab->symtab;
 | |
| 		sym_strtab = sec_symtab->link->strtab;
 | |
| 		for (j = 0; j < sec->shdr.sh_size/sizeof(Elf32_Rel); j++) {
 | |
| 			Elf32_Rel *rel;
 | |
| 			Elf32_Sym *sym;
 | |
| 			unsigned r_type;
 | |
| 			rel = &sec->reltab[j];
 | |
| 			sym = &sh_symtab[ELF32_R_SYM(rel->r_info)];
 | |
| 			r_type = ELF32_R_TYPE(rel->r_info);
 | |
| 			/* Don't visit relocations to absolute symbols */
 | |
| 			if (sym->st_shndx == SHN_ABS) {
 | |
| 				continue;
 | |
| 			}
 | |
| 			if (r_type == R_386_NONE || r_type == R_386_PC32) {
 | |
| 				/*
 | |
| 				 * NONE can be ignored and and PC relative
 | |
| 				 * relocations don't need to be adjusted.
 | |
| 				 */
 | |
| 			}
 | |
| 			else if (r_type == R_386_32) {
 | |
| 				/* Visit relocations that need to be adjusted */
 | |
| 				visit(rel, sym);
 | |
| 			}
 | |
| 			else {
 | |
| 				die("Unsupported relocation type: %d\n", r_type);
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void count_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
 | |
| {
 | |
| 	reloc_count += 1;
 | |
| }
 | |
| 
 | |
| static void collect_reloc(Elf32_Rel *rel, Elf32_Sym *sym)
 | |
| {
 | |
| 	/* Remember the address that needs to be adjusted. */
 | |
| 	relocs[reloc_idx++] = rel->r_offset;
 | |
| }
 | |
| 
 | |
| static int cmp_relocs(const void *va, const void *vb)
 | |
| {
 | |
| 	const unsigned long *a, *b;
 | |
| 	a = va; b = vb;
 | |
| 	return (*a == *b)? 0 : (*a > *b)? 1 : -1;
 | |
| }
 | |
| 
 | |
| static void emit_relocs(int as_text)
 | |
| {
 | |
| 	int i;
 | |
| 	/* Count how many relocations I have and allocate space for them. */
 | |
| 	reloc_count = 0;
 | |
| 	walk_relocs(count_reloc);
 | |
| 	relocs = malloc(reloc_count * sizeof(relocs[0]));
 | |
| 	if (!relocs) {
 | |
| 		die("malloc of %d entries for relocs failed\n",
 | |
| 			reloc_count);
 | |
| 	}
 | |
| 	/* Collect up the relocations */
 | |
| 	reloc_idx = 0;
 | |
| 	walk_relocs(collect_reloc);
 | |
| 
 | |
| 	/* Order the relocations for more efficient processing */
 | |
| 	qsort(relocs, reloc_count, sizeof(relocs[0]), cmp_relocs);
 | |
| 
 | |
| 	/* Print the relocations */
 | |
| 	if (as_text) {
 | |
| 		/* Print the relocations in a form suitable that
 | |
| 		 * gas will like.
 | |
| 		 */
 | |
| 		printf(".section \".data.reloc\",\"a\"\n");
 | |
| 		printf(".balign 4\n");
 | |
| 		for (i = 0; i < reloc_count; i++) {
 | |
| 			printf("\t .long 0x%08lx\n", relocs[i]);
 | |
| 		}
 | |
| 		printf("\n");
 | |
| 	}
 | |
| 	else {
 | |
| 		unsigned char buf[4];
 | |
| 		buf[0] = buf[1] = buf[2] = buf[3] = 0;
 | |
| 		/* Print a stop */
 | |
| 		printf("%c%c%c%c", buf[0], buf[1], buf[2], buf[3]);
 | |
| 		/* Now print each relocation */
 | |
| 		for (i = 0; i < reloc_count; i++) {
 | |
| 			buf[0] = (relocs[i] >>  0) & 0xff;
 | |
| 			buf[1] = (relocs[i] >>  8) & 0xff;
 | |
| 			buf[2] = (relocs[i] >> 16) & 0xff;
 | |
| 			buf[3] = (relocs[i] >> 24) & 0xff;
 | |
| 			printf("%c%c%c%c", buf[0], buf[1], buf[2], buf[3]);
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static void usage(void)
 | |
| {
 | |
| 	die("relocs [--abs-syms |--abs-relocs | --text] vmlinux\n");
 | |
| }
 | |
| 
 | |
| int main(int argc, char **argv)
 | |
| {
 | |
| 	int show_absolute_syms, show_absolute_relocs;
 | |
| 	int as_text;
 | |
| 	const char *fname;
 | |
| 	FILE *fp;
 | |
| 	int i;
 | |
| 
 | |
| 	show_absolute_syms = 0;
 | |
| 	show_absolute_relocs = 0;
 | |
| 	as_text = 0;
 | |
| 	fname = NULL;
 | |
| 	for (i = 1; i < argc; i++) {
 | |
| 		char *arg = argv[i];
 | |
| 		if (*arg == '-') {
 | |
| 			if (strcmp(argv[1], "--abs-syms") == 0) {
 | |
| 				show_absolute_syms = 1;
 | |
| 				continue;
 | |
| 			}
 | |
| 
 | |
| 			if (strcmp(argv[1], "--abs-relocs") == 0) {
 | |
| 				show_absolute_relocs = 1;
 | |
| 				continue;
 | |
| 			}
 | |
| 			else if (strcmp(argv[1], "--text") == 0) {
 | |
| 				as_text = 1;
 | |
| 				continue;
 | |
| 			}
 | |
| 		}
 | |
| 		else if (!fname) {
 | |
| 			fname = arg;
 | |
| 			continue;
 | |
| 		}
 | |
| 		usage();
 | |
| 	}
 | |
| 	if (!fname) {
 | |
| 		usage();
 | |
| 	}
 | |
| 	fp = fopen(fname, "r");
 | |
| 	if (!fp) {
 | |
| 		die("Cannot open %s: %s\n",
 | |
| 			fname, strerror(errno));
 | |
| 	}
 | |
| 	read_ehdr(fp);
 | |
| 	read_shdrs(fp);
 | |
| 	read_strtabs(fp);
 | |
| 	read_symtabs(fp);
 | |
| 	read_relocs(fp);
 | |
| 	if (show_absolute_syms) {
 | |
| 		print_absolute_symbols();
 | |
| 		return 0;
 | |
| 	}
 | |
| 	if (show_absolute_relocs) {
 | |
| 		print_absolute_relocs();
 | |
| 		return 0;
 | |
| 	}
 | |
| 	emit_relocs(as_text);
 | |
| 	return 0;
 | |
| }
 |