Rudimentary ELF64 loader and handling routines. More...

Functions
genvaddr_t	elf_virtual_base64 (struct Elf64_Ehdr *ehead)
	Calculates the base of the loadable portion of the elf image in virtual memory.

struct Elf64_Shdr *	elf64_find_section_header_type (struct Elf64_Shdr *shdr, uint32_t entries, uint32_t type)
	Return pointer to relocation section ELF header. More...

struct Elf64_Shdr *	elf64_find_section_header_name (genvaddr_t elf_base, size_t elf_bytes, const char *section_name)
	Return pointer to section header with given name. More...

struct Elf64_Sym *	elf64_find_symbol_by_name (genvaddr_t elf_base, size_t elf_bytes, const char name, uint8_t contains, uint8_t type, uintptr_t sindex)
	finds the symbol by name More...

struct Elf64_Sym *	elf64_find_symbol_by_addr (genvaddr_t elf_base, size_t elf_bytes, lvaddr_t addr, uintptr_t *sindex)
	finds the symbol by its address More...

void	elf64_relocate (genvaddr_t dst, genvaddr_t src, struct Elf64_Rela rela, size_t size, struct Elf64_Sym symtab, size_t symsize, genvaddr_t start, void *vbase)
	Relocates the ELF image from src to dst. More...

errval_t	elf64_load (uint16_t em_machine, elf_allocator_fn allocate_func, void state, lvaddr_t base, size_t size, genvaddr_t retentry, genvaddr_t ret_tlsbase, size_t ret_tlsinitlen, size_t *ret_tlstotallen)
	Load ELF64 binary image into memory. More...

Detailed Description

Rudimentary ELF64 loader and handling routines.

Note that on 32-bit platforms, this loader is only able to load ELF64 files that it can address (ie. those that are not bigger than what fits into a 32-bit address space).

Function Documentation

struct Elf64_Shdr* elf64_find_section_header_name	(	genvaddr_t	elf_base,
		size_t	elf_bytes,
		const char *	section_name
	)

Return pointer to section header with given name.

Parameters

elf_base	Address of ELF header
elf_bytes	Size of ELF file.
section_name	Named section to look for.

Returns: Pointer to ELF section header with name, or NULL.

struct Elf64_Shdr* elf64_find_section_header_type	(	struct Elf64_Shdr *	shdr,
		uint32_t	entries,
		uint32_t	type
	)

Return pointer to relocation section ELF header.

This function finds and returns a pointer to the first ELF section header of type 'type'.

Parameters

shdr	Pointer to head of ELF section header table.
entries	Number of entries in the ELF section header table.
type	ELF section header type to look for.

Returns: Pointer to first ELF section header of type 'type', or NULL.

struct Elf64_Sym* elf64_find_symbol_by_addr	(	genvaddr_t	elf_base,
		size_t	elf_bytes,
		lvaddr_t	addr,
		uintptr_t *	sindex
	)

finds the symbol by its address

Parameters

elf_base	virtual address where the elf image is mapped
elf_bytes	size of the mapped elf image
addr	virtual address of the symbol
sindex	returns the index of the symbol

Returns: pointer to the symbol NULL if there is none

struct Elf64_Sym* elf64_find_symbol_by_name	(	genvaddr_t	elf_base,
		size_t	elf_bytes,
		const char *	name,
		uint8_t	contains,
		uint8_t	type,
		uintptr_t *	sindex
	)

finds the symbol by name

Parameters

elf_base	virtual address where the elf image is mapped
elf_bytes	size of the mapped elf image
name	name of the symbol to look for
contains	if non zero, search for containing rather than exact match
type	type of the symbol STT_*
sindex	index where to start and returns the index of the symbol

Returns: pointer to the symbol NULL if there is none

errval_t elf64_load	(	uint16_t	em_machine,
		elf_allocator_fn	allocate_func,
		void *	state,
		lvaddr_t	base,
		size_t	size,
		genvaddr_t *	retentry,
		genvaddr_t *	ret_tlsbase,
		size_t *	ret_tlsinitlen,
		size_t *	ret_tlstotallen
	)

Load ELF64 binary image into memory.

This function loads an ELF64 binary image, based at 'base' and of size 'size' into the memory provided by 'allocate'

Parameters

em_machine	ELF machine type.
allocate	Memory allocation function.
state	Pointer to state for allocation function.
base	Base address of ELF64 binary image in memory.
size	Size of ELF64 binary image in bytes.
retentry	Used to return entry point address
ret_tlsbase	Used to return TLS block base address
ret_tlsinitlen	Used to return length of initialised TLS data block
ret_tlstotallen	Used to return total length of TLS data

void elf64_relocate	(	genvaddr_t	dst,
		genvaddr_t	src,
		struct Elf64_Rela *	rela,
		size_t	size,
		struct Elf64_Sym *	symtab,
		size_t	symsize,
		genvaddr_t	start,
		void *	vbase
	)

Relocates the ELF image from src to dst.

This function processes the ELF relocation section 'rela' of size 'size' of the ELF image, formerly located at 'src', to the new location 'dst'. Relocation is necessary for certain variables that cannot be coded as position-independent code.

Parameters

dst	Address to relocate to.
src	Former base address of the ELF image.
rela	Pointer to relocation section of the ELF image.
size	Size in bytes of the ELF relocation section.
symtab	Pointer to ELF symbol table.
symsize	Size in bytes of the ELF symbol table.
start	Original base address of the ELF image (needed for symbol-table-based relocations – we don't touch the symbol table).
vbase	Pointer to ELF image in virtual memory.

Functions

Detailed Description

Function Documentation