Asm

/* $Id$ */
/* Copyright (c) 2011-2018 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS Devel Asm */
/* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <string.h>
#include <System.h>
#include "Asm.h"
/* Dalvik */
/* private */
/* types */
struct _AsmArchPlugin
{
AsmArchPluginHelper * helper;
};
typedef struct _DalvikDecode
{
AsmArchPlugin * plugin;
AsmArchInstructionCall * call;
int u8;
} DalvikDecode;
/* constants */
/* register sizes */
#define REG(name, size, id, flags, description) \
REG_dalvik_ ## name ## _size = size,
enum
{
#include "dalvik.reg"
REG_dalvik_size_count
};
#undef REG
/* register ids */
#define REG(name, size, id, flags, description) REG_dalvik_ ## name ## _id = id,
enum
{
#include "dalvik.reg"
REG_dalvik_id_count
};
#undef REG
/* variables */
/* plug-in */
static AsmArchDefinition const _dalvik_definition =
{
"dex", ASM_ARCH_ENDIAN_LITTLE, 32, 16, 0
};
#define REG(name, size, id, flags, description) \
{ "" # name, size, id, flags, description },
static AsmArchRegister const _dalvik_registers[] =
{
#include "dalvik.reg"
#include "null.reg"
};
#undef REG
static AsmArchInstruction const _dalvik_instructions[] =
{
#include "dalvik.ins"
#include "common.ins"
#include "null.ins"
};
/* prototypes */
/* plug-in */
static AsmArchPlugin * _dalvik_init(AsmArchPluginHelper * helper);
static void _dalvik_destroy(AsmArchPlugin * plugin);
static int _dalvik_encode(AsmArchPlugin * plugin,
AsmArchPrefix const * prefix,
AsmArchInstruction const * instruction,
AsmArchInstructionCall const * call);
static int _dalvik_decode(AsmArchPlugin * plugin,
AsmArchInstructionCall * call);
/* public */
/* variables */
AsmArchPluginDefinition arch_plugin =
{
"dalvik",
"Dalvik bytecode",
LICENSE_GNU_LGPL3_FLAGS,
&_dalvik_definition,
_dalvik_registers,
NULL,
_dalvik_instructions,
_dalvik_init,
_dalvik_destroy,
_dalvik_encode,
_dalvik_decode
};
/* private */
/* functions */
/* dalvik_init */
static AsmArchPlugin * _dalvik_init(AsmArchPluginHelper * helper)
{
AsmArchPlugin * plugin;
if((plugin = object_new(sizeof(*plugin))) == NULL)
return NULL;
plugin->helper = helper;
return plugin;
}
/* dalvik_destroy */
static void _dalvik_destroy(AsmArchPlugin * plugin)
{
object_delete(plugin);
}
/* dalvik_encode */
static int _dalvik_encode(AsmArchPlugin * plugin,
AsmArchPrefix const * prefix,
AsmArchInstruction const * instruction,
AsmArchInstructionCall const * call)
{
AsmArchPluginHelper * helper = plugin->helper;
uint8_t u8;
uint16_t u16;
void const * buf;
ssize_t size;
if(prefix != NULL)
return -error_set_code(1, "%s: %s",
helper->get_filename(helper->arch),
"Prefixes not supported for this architecture");
/* FIXME really implement */
switch(AO_GET_SIZE(instruction->flags))
{
case 8:
u8 = instruction->opcode;
buf = &u8;
size = sizeof(u8);
break;
case 16:
u16 = _htol16(instruction->opcode);
buf = &u16;
size = sizeof(u16);
break;
default:
/* FIXME should not happen */
return -error_set_code(1, "%s: %s",
helper->get_filename(helper->arch),
"Invalid size for opcode");
}
if(helper->write(helper->arch, buf, size) != size)
return -1;
return 0;
}
/* dalvik_decode */
static int _dalvik_decode_immediate(DalvikDecode * dd, size_t i);
static int _dalvik_decode_operand(DalvikDecode * dd, size_t i);
static int _dalvik_decode_register(DalvikDecode * dd, size_t i);
static int _dalvik_decode(AsmArchPlugin * plugin,
AsmArchInstructionCall * call)
{
DalvikDecode dd;
AsmArchPluginHelper * helper = plugin->helper;
uint8_t u8;
uint16_t u16;
AsmArchInstruction const * ai;
size_t i;
dd.plugin = plugin;
dd.call = call;
dd.u8 = -1;
/* FIXME detect end of input */
if(helper->read(helper->arch, &u8, sizeof(u8)) != sizeof(u8))
return -1;
if((ai = helper->get_instruction_by_opcode(helper->arch, 8, u8))
== NULL)
{
u16 = u8;
if(helper->read(helper->arch, &u8, sizeof(u8)) != sizeof(u8))
{
call->name = "db";
call->operands[0].definition = AO_IMMEDIATE(0, 8, 0);
call->operands[0].value.immediate.name = NULL;
call->operands[0].value.immediate.value = u16;
call->operands[0].value.immediate.negative = 0;
call->operands_cnt = 1;
return 0;
}
u16 = _htol16((u16 << 8) | u8);
if((ai = helper->get_instruction_by_opcode(helper->arch, 16,
u16)) == NULL)
{
call->name = "dw";
call->operands[0].definition = AO_IMMEDIATE(0, 16, 0);
call->operands[0].value.immediate.name = NULL;
call->operands[0].value.immediate.value = u16;
call->operands[0].value.immediate.negative = 0;
call->operands_cnt = 1;
return 0;
}
}
call->name = ai->name;
call->operands[0].definition = ai->op1;
call->operands[1].definition = ai->op2;
call->operands[2].definition = ai->op3;
for(i = 0; i < 3 && AO_GET_TYPE(call->operands[i].definition)
!= AOT_NONE; i++)
if(_dalvik_decode_operand(&dd, i) != 0)
return -1;
call->operands_cnt = i;
return 0;
}
static int _dalvik_decode_immediate(DalvikDecode * dd, size_t i)
{
AsmArchPluginHelper * helper = dd->plugin->helper;
AsmArchOperand * ao = &dd->call->operands[i];
uint8_t u8;
uint16_t u16;
uint32_t u32;
AsmFunction * af;
AsmString * as;
switch(AO_GET_SIZE(ao->definition))
{
case 4:
if(dd->u8 >= 0)
{
ao->value.immediate.value = dd->u8 & 0xf;
dd->u8 = -1;
break;
}
if(helper->read(helper->arch, &u8, sizeof(u8))
!= sizeof(u8))
return -1;
ao->value.immediate.value = u8 >> 4;
dd->u8 = u8;
break;
case 8:
if(helper->read(helper->arch, &u8, sizeof(u8))
!= sizeof(u8))
return -1;
ao->value.immediate.value = u8;
break;
case 16:
if(helper->read(helper->arch, &u16, sizeof(u16))
!= sizeof(u16))
return -1;
ao->value.immediate.value = _htol16(u16);
break;
case 32:
if(helper->read(helper->arch, &u32, sizeof(u32))
!= sizeof(u32))
return -1;
ao->value.immediate.value = _htol32(u32);
break;
default:
return -error_set_code(1, "%s", "Unsupported immediate"
" operand");
}
switch(AO_GET_VALUE(ao->definition))
{
case AOI_REFERS_FUNCTION:
af = helper->get_function_by_id(helper->arch,
ao->value.immediate.value);
if(af != NULL)
ao->value.immediate.name = af->name;
break;
case AOI_REFERS_STRING:
as = helper->get_string_by_id(helper->arch,
ao->value.immediate.value);
if(as != NULL)
ao->value.immediate.name = as->name;
break;
}
ao->value.immediate.negative = 0;
return 0;
}
static int _dalvik_decode_operand(DalvikDecode * dd, size_t i)
{
switch(AO_GET_TYPE(dd->call->operands[i].definition))
{
case AOT_IMMEDIATE:
return _dalvik_decode_immediate(dd, i);
case AOT_REGISTER:
return _dalvik_decode_register(dd, i);
default:
return -error_set_code(1, "%s", "Unsupported operand"
" type");
}
return 0;
}
static int _dalvik_decode_register(DalvikDecode * dd, size_t i)
{
AsmArchPluginHelper * helper = dd->plugin->helper;
AsmArchOperandDefinition aod = dd->call->operands[i].definition;
uint32_t id;
uint8_t u8;
uint16_t u16;
AsmArchRegister const * ar;
if(AO_GET_FLAGS(aod) & AOF_IMPLICIT)
id = AO_GET_VALUE(aod);
else if(AO_GET_FLAGS(aod) & AOF_DALVIK_REGSIZE)
{
switch(AO_GET_VALUE(aod))
{
case 4:
if(dd->u8 >= 0)
{
id = dd->u8 & 0xf;
dd->u8 = -1;
break;
}
if(helper->read(helper->arch, &u8, sizeof(u8))
!= sizeof(u8))
return -1;
id = u8 >> 4;
dd->u8 = u8;
break;
case 8:
if(helper->read(helper->arch, &u8, sizeof(u8))
!= sizeof(u8))
return -1;
id = u8;
break;
case 16:
if(helper->read(helper->arch, &u16, sizeof(u16))
!= sizeof(u16))
return -1;
id = _htol16(u16);
break;
default:
return -1;
}
}
else
return -error_set_code(1, "%s", "Unsupported register operand");
if(id >= 256)
/* FIXME give the real name instead */
dd->call->operands[i].value._register.name = ">256";
else if((ar = helper->get_register_by_id_size(helper->arch, id, 32))
!= NULL)
dd->call->operands[i].value._register.name = ar->name;
else
return -1;
return 0;
}