/*****************************************************************************/

/*  pemagination: a (virtual) tour into portable bits and executable bytes   */

/*  Copyright (C) 2013,2014,2015  Z. Gilboa                                  */

/*  Released under GPLv2 and GPLv3; see COPYING.PEMAGINE.                    */

/*****************************************************************************/

#include <psxtypes/psxtypes.h>

#include <pemagine/pemagine.h>

/* private args structure */

struct pe_symbol_name_ctx {

	const void *	addr;

	char *		name;

};

/* private forward declarations */

static int pe_enum_exports_callback(

	const void *			base,

	struct pe_export_hdr *		exp_hdr,

	struct pe_export_sym *		sym,

	enum pe_callback_reason		reason,

	void *				context);

#if defined (__NT32)

static char * pe_get_imported_symbol_info_32(

	const void *			sym_addr,

	void **				sym_image_addr,

	char **				sym_name,

	struct pe_ldr_tbl_entry **	ldr_tbl_entry);

#endif

#if defined (__NT64)

static char * pe_get_imported_symbol_info_64(

	const void *			sym_addr,

	void **				sym_image_addr,

	char **				sym_name,

	struct pe_ldr_tbl_entry **	ldr_tbl_entry);

#endif

pe_api

char * pe_get_symbol_name(const void * base, const void * sym_addr)

{

	struct pe_export_sym		exp_item;

	struct pe_symbol_name_ctx	ctx;

	ctx.name = 0;

	ctx.addr = sym_addr;

	pe_enum_image_exports(

		base,

		pe_enum_exports_callback,

		&exp_item,

		&ctx;;

	return ctx.name;

}

pe_api

char * pe_get_import_symbol_info(

	const void *			sym_addr,

	void **				sym_image_addr,

	char **				sym_name,

	struct pe_ldr_tbl_entry **	ldr_tbl_entry)

{

	#if defined(__NT32)

		return pe_get_imported_symbol_info_32(

			sym_addr,

			sym_image_addr,

			sym_name,

			ldr_tbl_entry);

	#elif defined (__NT64)

		return pe_get_imported_symbol_info_64(

			sym_addr,

			sym_image_addr,

			sym_name,

			ldr_tbl_entry);

	#endif

}

static int pe_enum_exports_callback(

	const void *			base,

	struct pe_export_hdr *		exp_hdr,

	struct pe_export_sym  *		sym,

	enum pe_callback_reason		reason,

	void *				context)

{

	struct pe_symbol_name_ctx * ctx;

	if (reason != PE_CALLBACK_REASON_ITEM)

		return 1;

	ctx = (struct pe_symbol_name_ctx *)context;

	if (sym->addr == ctx->addr) {

		ctx->name = sym->name;

		return 0;

	} else

		return 1;

}

#ifdef __NT32

static char * pe_get_imported_symbol_info_32(

	const void *			sym_addr,

	void **				sym_image_addr,

	char **				sym_name,

	struct pe_ldr_tbl_entry **	ldr_tbl_entry)

{

	struct symbol {

		unsigned char	call;

		unsigned char	ds;

		unsigned char	sym_addr[4];

		unsigned char	padding[2];

	};

	char *				fn_name;

	struct pe_ldr_tbl_entry *	mod_info;

	void *				mod_base;

	uint32_t ***			sym_redirected_addr;

	struct symbol *			sym;

	fn_name  = 0;

	mod_info = 0;

	sym = (struct symbol *)sym_addr;

	if ((sym->call == 0xff) && (sym->ds == 0x25)) {

		sym_redirected_addr = (uint32_t ***)sym->sym_addr;

		if (sym_redirected_addr)

			mod_info = pe_get_symbol_module_info(**sym_redirected_addr);

		if (mod_info)

			mod_base = mod_info->dll_base;

		else

			mod_base = (void *)0;

		if (mod_base)

			fn_name = pe_get_symbol_name(

				mod_base,

				**sym_redirected_addr);

	}

	if (fn_name && ldr_tbl_entry)

		*ldr_tbl_entry = mod_info;

	return fn_name;

}

#endif

#ifdef __NT64

static char * pe_get_imported_symbol_info_64(

	const void *			sym_addr,

	void **				sym_image_addr,

	char **				sym_name,

	struct pe_ldr_tbl_entry **	ldr_tbl_entry)

{

	struct symbol {

		unsigned char	call;

		unsigned char	ds;

		unsigned char	sym_addr[4];

		unsigned char	padding[2];

	};

	char *				fn_name;

	struct pe_ldr_tbl_entry *	mod_info;

	void *				mod_base;

	uint32_t *			sym_offset;

	uint32_t			offset;

	struct symbol *			sym;

	fn_name  = 0;

	mod_info = 0;

	sym = (struct symbol *)sym_addr;

	if ((sym->call == 0xff) && (sym->ds == 0x25)) {

		sym_offset = (uint32_t *)sym->sym_addr;

		if (sym_offset) {

			offset		= *sym_offset;

			sym_addr	= *(void **)(offset + (uintptr_t)(++sym_offset));

			mod_info	= pe_get_symbol_module_info(sym_addr);

		}

		if (mod_info)

			mod_base = mod_info->dll_base;

		else

			mod_base = (void *)0;

		if (mod_base)

			fn_name = pe_get_symbol_name(mod_base,sym_addr);

	}

	if (fn_name) {

		if (ldr_tbl_entry)

			*ldr_tbl_entry = mod_info;

		if (sym_image_addr)

			*sym_image_addr = (void *)sym_addr;

		if (sym_name)

			*sym_name = fn_name;

	}

	return fn_name;

}

#endif