/* OpenIDA - Outil d'analyse de fichiers binaires
* operand.c - gestion des operandes de l'architecture x86
*
* Copyright (C) 2008 Cyrille Bagard
*
* This file is part of OpenIDA.
*
* OpenIDA 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 3 of the License, or
* (at your option) any later version.
*
* OpenIDA 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Foobar. If not, see .
*/
#include "operand.h"
#include
#include
#include
#include "../operand.h"
#include "../operand-int.h"
/* Liste des registres 8 bits */
typedef enum _X868bRegister
{
X86_REG8_AL = 0, /* Registre AL */
X86_REG8_CL = 1, /* Registre AL */
X86_REG8_DL = 2, /* Registre AL */
X86_REG8_BL = 3, /* Registre AL */
X86_REG8_AH = 4, /* Registre AH */
X86_REG8_CH = 5, /* Registre AH */
X86_REG8_DH = 6, /* Registre AH */
X86_REG8_BH = 7, /* Registre AH */
X86_REG8_NONE /* Aucun registre */
} X868bRegister;
/* Liste des registres 16 bits */
typedef enum _X8616bRegister
{
X86_REG16_AX = 0, /* Registre AX */
X86_REG16_CX = 1, /* Registre AX */
X86_REG16_DX = 2, /* Registre AX */
X86_REG16_BX = 3, /* Registre AX */
X86_REG16_SP = 4, /* Registre SP */
X86_REG16_BP = 5, /* Registre BP */
X86_REG16_SI = 6, /* Registre SI */
X86_REG16_DI = 7, /* Registre DI */
X86_REG16_NONE /* Aucun registre */
} X8616bRegister;
/* Liste des registres 32 bits */
typedef enum _X8632bRegister
{
X86_REG32_EAX = 0, /* Registre EAX */
X86_REG32_ECX = 1, /* Registre EAX */
X86_REG32_EDX = 2, /* Registre EAX */
X86_REG32_EBX = 3, /* Registre EAX */
X86_REG32_ESP = 4, /* Registre ESP */
X86_REG32_EBP = 5, /* Registre EBP */
X86_REG32_ESI = 6, /* Registre ESI */
X86_REG32_EDI = 7, /* Registre EDI */
X86_REG32_NONE /* Aucun registre */
} X8632bRegister;
/* Registre X86 */
typedef union _x86_register
{
X868bRegister reg8; /* Registre 8 bits */
X8616bRegister reg16; /* Registre 16 bits */
X8632bRegister reg32; /* Registre 32 bits */
} x86_register;
/* Définition d'une opérande x86 */
struct _asm_x86_operand
{
asm_operand base; /* A laisser en premier */
x86_register rindex; /* Registre servant d'indice */
bool content; /* Contenu d'un registre */
uint8_t scale; /* Puissance de deux */
x86_register rbase; /* Registre de base */
asm_operand *displacement; /* Décallage supplémentaire */
};
#define NULL ((void *)0)
/* Récupère l'indentifiant interne d'un registre. */
bool get_x86_register(x86_register *, AsmOperandSize, uint8_t);
/* Traduit une opérande de registre en texte. */
void _x86_print_reg_operand(const x86_register *reg, AsmOperandSize, char *, size_t, AsmSyntax);
/******************************************************************************
* *
* Paramètres : - *
* *
* Description : Crée une opérande vierge pour x86. *
* *
* Retour : Opérande nouvellement créée. *
* *
* Remarques : - *
* *
******************************************************************************/
asm_x86_operand *create_new_x86_operand(void)
{
asm_x86_operand *result; /* Structure à retourner */
result = (asm_x86_operand *)calloc(1, sizeof(asm_x86_operand));
result->scale = 0;
result->rbase.reg32 = X86_REG32_NONE;
return result;
}
/******************************************************************************
* *
* Paramètres : reg = registre à définir. [OUT] *
* size = indique la taille du registre. *
* value = valeur correspondant au registre. *
* *
* Description : Récupère l'indentifiant interne d'un registre. *
* *
* Retour : true si la définition est opérée, false sinon. *
* *
* Remarques : - *
* *
******************************************************************************/
bool get_x86_register(x86_register *reg, AsmOperandSize size, uint8_t value)
{
switch (size)
{
case AOS_8_BITS:
return false;
break;
case AOS_16_BITS:
switch (value)
{
case 0 ... 7:
reg->reg16 = (X8616bRegister)value;
break;
default:
return false;
break;
}
break;
case AOS_32_BITS:
switch (value)
{
case 0 ... 7:
reg->reg32 = (X8632bRegister)value;
break;
default:
return false;
break;
}
break;
case AOS_64_BITS:
return false;
break;
}
return true;
}
/******************************************************************************
* *
* Paramètres : data = donnée à analyser. *
* is_reg32 = indique si le registre est un registre 32 bits. *
* base = valeur du premier registre. *
* *
* Description : Crée une opérande renvoyant vers un registre 16 ou 32 bits. *
* *
* Retour : Opérande mise en place ou NULL. *
* *
* Remarques : - *
* *
******************************************************************************/
asm_x86_operand *x86_create_reg1632_operand(uint8_t data, bool is_reg32, uint8_t base)
{
asm_x86_operand *result; /* Registre à retourner */
result = create_new_x86_operand();
ASM_OPERAND(result)->type = AOT_REG;
ASM_OPERAND(result)->size = (is_reg32 ? AOS_32_BITS : AOS_16_BITS);
if (!get_x86_register(&result->rindex, ASM_OPERAND(result)->size, data - base))
{
free(result);
return NULL;
}
return result;
}
/******************************************************************************
* *
* Paramètres : data = donnée à analyser. *
* is_reg32 = indique si le registre est un registre 32 bits. *
* first = indique la partie du ModR/M à traiter. *
* *
* Description : Crée une opérande renvoyant vers un registre 16 ou 32 bits. *
* *
* Retour : Opérande mise en place ou NULL. *
* *
* Remarques : - *
* *
******************************************************************************/
asm_x86_operand *x86_create_reg1632_operand_from_modrm(uint8_t data, bool is_reg32, bool first)
{
asm_x86_operand *result; /* Registre à retourner */
uint8_t reg; /* Transcription du registre */
if (first) reg = data & 0x07;
else reg = (data & 0x38) >> 3;
result = create_new_x86_operand();
ASM_OPERAND(result)->type = AOT_REG;
ASM_OPERAND(result)->size = (is_reg32 ? AOS_32_BITS : AOS_16_BITS);
if (!get_x86_register(&result->rindex, ASM_OPERAND(result)->size, reg))
{
free(result);
return NULL;
}
return result;
}
/******************************************************************************
* *
* Paramètres : data = flux de données à analyser. *
* pos = position courante dans ce flux. [OUT] *
* len = taille totale des données à analyser. *
* is_reg32 = indique si le registre est un registre 32 bits. *
* first = indique la partie du ModR/M à traiter. *
* *
* Description : Crée une opérande renvoyant vers un contenu 16 ou 32 bits. *
* *
* Retour : Opérande mise en place ou NULL. *
* *
* Remarques : - *
* *
******************************************************************************/
asm_x86_operand *x86_create_content1632_operand(const uint8_t *data, off_t *pos, off_t len, bool is_reg32, bool first)
{
asm_x86_operand *result; /* Registre à retourner */
uint8_t mod; /* Modificateur présent */
/* Pas de contenu */
mod = (data[*pos] & 0xc0);
if (mod == 0xc0) return NULL;
result = x86_create_reg1632_operand_from_modrm(data[*pos], is_reg32, first);
if (result == NULL) return NULL;
result->content = true;
(*pos)++;
/* Vieille astuce de l'emplacement mémoire fixe ? */
if (result->rindex.reg32 == X86_REG32_EBP && mod == 0x00)
{
free(result);
result = create_new_x86_operand();
if (!fill_imm_operand(ASM_OPERAND(result), AOS_32_BITS/* FIXME ? */, data, pos, len))
{
(*pos)--;
free(result);
return NULL;
}
return result;
}
/* A la recherche d'un SIB */
if (result->rindex.reg32 == X86_REG32_ESP)
{
if (!get_x86_register(&result->rbase, ASM_OPERAND(result)->size, data[*pos] & 0x07))
{
(*pos)--;
free(result);
return NULL;
}
if (!get_x86_register(&result->rindex, ASM_OPERAND(result)->size, (data[*pos] & 0x38) >> 3))
{
(*pos)--;
free(result);
return NULL;
}
result->scale = ((data[*pos] & 0xc0) >> 6);
if (result->rindex.reg32 == X86_REG32_ESP)
{
result->rindex.reg32 = result->rbase.reg32;
result->rbase.reg32 = X86_REG32_NONE;
}
(*pos)++;
}
/* Décallage supplémentaire ? */
switch (mod)
{
case 0x00:
if (result->rbase.reg32 == X86_REG32_EBP)
{
result->rbase.reg32 = X86_REG32_NONE;
result->displacement = create_new_x86_operand();
if (!fill_imm_operand(ASM_OPERAND(result->displacement), ASM_OPERAND(result)->size, data, pos, len))
{
(*pos) -= 2;
free(result->displacement);
free(result);
return NULL;
}
}
break;
case 0x40:
result->displacement = create_new_x86_operand();
if (!fill_imm_operand(ASM_OPERAND(result->displacement), AOS_8_BITS, data, pos, len))
{
(*pos) -= 2;
free(result->displacement);
free(result);
return NULL;
}
break;
case 0x80:
result->displacement = create_new_x86_operand();
if (!fill_imm_operand(ASM_OPERAND(result->displacement), AOS_32_BITS, data, pos, len))
{
(*pos) -= 2;
free(result->displacement);
free(result);
return NULL;
}
break;
}
return result;
}
/******************************************************************************
* *
* Paramètres : reg = registre à imprimer. *
* size = indique la taille du registre. *
* buffer = tampon de sortie mis à disposition. [OUT] *
* len = taille de ce tampon. *
* syntax = type de représentation demandée. *
* *
* Description : Traduit une opérande de registre en texte. *
* *
* Retour : - *
* *
* Remarques : - *
* *
******************************************************************************/
void _x86_print_reg_operand(const x86_register *reg, AsmOperandSize size, char *buffer, size_t len, AsmSyntax syntax)
{
switch (syntax)
{
case ASX_INTEL:
switch (size)
{
case AOS_8_BITS:
switch (reg->reg8)
{
case X86_REG8_AL:
snprintf(buffer, len, "al");
break;
case X86_REG8_CL:
snprintf(buffer, len, "cl");
break;
case X86_REG8_DL:
snprintf(buffer, len, "dl");
break;
case X86_REG8_BL:
snprintf(buffer, len, "bl");
break;
case X86_REG8_AH:
snprintf(buffer, len, "ah");
break;
case X86_REG8_CH:
snprintf(buffer, len, "ch");
break;
case X86_REG8_DH:
snprintf(buffer, len, "dh");
break;
case X86_REG8_BH:
snprintf(buffer, len, "bh");
break;
case X86_REG8_NONE:
/* Ne devrait jamais arriver */
break;
}
break;
case AOS_16_BITS:
switch (reg->reg16)
{
case X86_REG16_AX:
snprintf(buffer, len, "ax");
break;
case X86_REG16_CX:
snprintf(buffer, len, "cx");
break;
case X86_REG16_DX:
snprintf(buffer, len, "dx");
break;
case X86_REG16_BX:
snprintf(buffer, len, "bx");
break;
case X86_REG16_SP:
snprintf(buffer, len, "sp");
break;
case X86_REG16_BP:
snprintf(buffer, len, "bp");
break;
case X86_REG16_SI:
snprintf(buffer, len, "si");
break;
case X86_REG16_DI:
snprintf(buffer, len, "di");
break;
case X86_REG16_NONE:
/* Ne devrait jamais arriver */
break;
}
break;
case AOS_32_BITS:
switch (reg->reg32)
{
case X86_REG32_EAX:
snprintf(buffer, len, "eax");
break;
case X86_REG32_ECX:
snprintf(buffer, len, "ecx");
break;
case X86_REG32_EDX:
snprintf(buffer, len, "edx");
break;
case X86_REG32_EBX:
snprintf(buffer, len, "ebx");
break;
case X86_REG32_ESP:
snprintf(buffer, len, "esp");
break;
case X86_REG32_EBP:
snprintf(buffer, len, "ebp");
break;
case X86_REG32_ESI:
snprintf(buffer, len, "esi");
break;
case X86_REG32_EDI:
snprintf(buffer, len, "edi");
break;
case X86_REG32_NONE:
/* Ne devrait jamais arriver */
break;
}
break;
case AOS_64_BITS:
break;
}
break;
case ASX_ATT:
switch (size)
{
case AOS_8_BITS:
switch (reg->reg8)
{
case X86_REG8_AL:
snprintf(buffer, len, "%%al");
break;
case X86_REG8_CL:
snprintf(buffer, len, "%%cl");
break;
case X86_REG8_DL:
snprintf(buffer, len, "%%dl");
break;
case X86_REG8_BL:
snprintf(buffer, len, "%%bl");
break;
case X86_REG8_AH:
snprintf(buffer, len, "%%ah");
break;
case X86_REG8_CH:
snprintf(buffer, len, "%%ch");
break;
case X86_REG8_DH:
snprintf(buffer, len, "%%dh");
break;
case X86_REG8_BH:
snprintf(buffer, len, "%%bh");
break;
case X86_REG8_NONE:
/* Ne devrait jamais arriver */
break;
}
break;
case AOS_16_BITS:
switch (reg->reg16)
{
case X86_REG16_AX:
snprintf(buffer, len, "%%ax");
break;
case X86_REG16_CX:
snprintf(buffer, len, "%%cx");
break;
case X86_REG16_DX:
snprintf(buffer, len, "%%dx");
break;
case X86_REG16_BX:
snprintf(buffer, len, "%%bx");
break;
case X86_REG16_SP:
snprintf(buffer, len, "%%sp");
break;
case X86_REG16_BP:
snprintf(buffer, len, "%%bp");
break;
case X86_REG16_SI:
snprintf(buffer, len, "%%si");
break;
case X86_REG16_DI:
snprintf(buffer, len, "%%di");
break;
case X86_REG16_NONE:
/* Ne devrait jamais arriver */
break;
}
break;
case AOS_32_BITS:
switch (reg->reg32)
{
case X86_REG32_EAX:
snprintf(buffer, len, "%%eax");
break;
case X86_REG32_ECX:
snprintf(buffer, len, "%%ecx");
break;
case X86_REG32_EDX:
snprintf(buffer, len, "%%edx");
break;
case X86_REG32_EBX:
snprintf(buffer, len, "%%ebx");
break;
case X86_REG32_ESP:
snprintf(buffer, len, "%%esp");
break;
case X86_REG32_EBP:
snprintf(buffer, len, "%%ebp");
break;
case X86_REG32_ESI:
snprintf(buffer, len, "%%esi");
break;
case X86_REG32_EDI:
snprintf(buffer, len, "%%edi");
break;
case X86_REG32_NONE:
/* Ne devrait jamais arriver */
break;
}
break;
case AOS_64_BITS:
break;
}
break;
}
}
/******************************************************************************
* *
* Paramètres : operand = instruction à traiter. *
* buffer = tampon de sortie mis à disposition. [OUT] *
* len = taille de ce tampon. *
* syntax = type de représentation demandée. *
* *
* Description : Traduit une opérande de registre en texte. *
* *
* Retour : - *
* *
* Remarques : - *
* *
******************************************************************************/
void x86_print_reg_operand(const asm_x86_operand *operand, char *buffer, size_t len, AsmSyntax syntax)
{
size_t pos; /* Position de traitement */
switch (syntax)
{
case ASX_INTEL:
if (operand->content)
{
strcpy(buffer, "[");
if (operand->scale > 0)
snprintf(&buffer[1], len - 1, "%d*", (int)pow(2, operand->scale));
pos = strlen(buffer);
}
else pos = 0;
_x86_print_reg_operand(&operand->rindex, ASM_OPERAND(operand)->size, &buffer[pos], len - pos, syntax);
if (operand->rbase.reg32 != X86_REG32_NONE)
{
strcat(buffer, "+"); /* TODO: n */
pos = strlen(buffer);
_x86_print_reg_operand(&operand->rbase, ASM_OPERAND(operand)->size, &buffer[pos], len - pos, syntax);
}
if (operand->displacement != NULL)
{
strcat(buffer, "+"); /* TODO: n */
pos = strlen(buffer);
print_imm_operand(operand->displacement, &buffer[pos], len - pos, syntax);
}
if (operand->content) strcat(buffer, "]");
break;
case ASX_ATT:
break;
}
}