OllyDbg汇编/反汇编引擎

// Free Disassembler and Assembler -- Assembler // // Copyright (C) 2001 Oleh Yuschuk // // This program 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 2 of the License, or // (at your option) any later version. // // 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 General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program; if not, write to the Free Software // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA // 16.01.2002 - corrected error in processing of immediate constants. #define _CRT_SECURE_NO_WARNINGS #define STRICT #include <windows.h> #include <stdio.h> #include <string.h> #include <ctype.h> //#include <dir.h> #include <math.h> #include <float.h> #pragma hdrstop #include "disasm.h" //////////////////////////////////////////////////////////////////////////////// ///////////////////////////// ASSEMBLER FUNCTIONS ////////////////////////////// // Scanner modes. #define SA_NAME 0x0001 // Don't try to decode labels #define SA_IMPORT 0x0002 // Allow import pseudolabel // Types of input tokens reported by scanner. #define SCAN_EOL 0 // End of line #define SCAN_REG8 1 // 8-bit register #define SCAN_REG16 2 // 16-bit register #define SCAN_REG32 3 // 32-bit register #define SCAN_SEG 4 // Segment register #define SCAN_FPU 5 // FPU register #define SCAN_MMX 6 // MMX register #define SCAN_CR 7 // Control register #define SCAN_DR 8 // Debug register #define SCAN_OPSIZE 9 // Operand size modifier #define SCAN_JMPSIZE 10 // Jump size modifier #define SCAN_LOCAL 11 // Address on stack in form LOCAL.decimal #define SCAN_ARG 12 // Address on stack in form ARG.decimal #define SCAN_PTR 20 // PTR in MASM addressing statements #define SCAN_REP 21 // REP prefix #define SCAN_REPE 22 // REPE prefix #define SCAN_REPNE 23 // REPNE prefix #define SCAN_LOCK 24 // LOCK prefix #define SCAN_NAME 25 // Command or label #define SCAN_ICONST 26 // Hexadecimal constant #define SCAN_DCONST 27 // Decimal constant #define SCAN_OFS 28 // Undefined constant #define SCAN_FCONST 29 // Floating-point constant #define SCAN_EIP 30 // Register EIP #define SCAN_SIGNED 31 // Keyword "SIGNED" (in expressions) #define SCAN_UNSIGNED 32 // Keyword "UNSIGNED" (in expressions) #define SCAN_CHAR 33 // Keyword "CHAR" (in expressions) #define SCAN_FLOAT 34 // Keyword "FLOAT" (in expressions) #define SCAN_DOUBLE 35 // Keyword "DOUBLE" (in expressions) #define SCAN_FLOAT10 36 // Keyword "FLOAT10" (in expressions) #define SCAN_STRING 37 // Keyword "STRING" (in expressions) #define SCAN_UNICODE 38 // Keyword "UNICODE" (in expressions) #define SCAN_MSG 39 // Pseudovariable MSG (in expressions) #define SCAN_SYMB 64 // Any other character #define SCAN_IMPORT 65 // Import pseudolabel #define SCAN_ERR 255 // Definitely bad item // Definition used by Assembler to report command matching errors. #define MA_JMP 0x0001 // Invalid jump size modifier #define MA_NOP 0x0002 // Wrong number of operands #define MA_TYP 0x0004 // Bad operand type #define MA_NOS 0x0008 // Explicit operand size expected #define MA_SIZ 0x0010 // Bad operand size #define MA_DIF 0x0020 // Different operand sizes #define MA_SEG 0x0040 // Invalid segment register #define MA_RNG 0x0080 // Constant out of expected range typedef struct t_asmoperand { int type; // Operand type, see beginning of file int size; // Operand size or 0 if yet unknown int index; // Index or other register int scale; // Scale int base; // Base register if present long offset; // Immediate value or offset int anyoffset; // Offset is present but undefined int segment; // Segment in address if present int jmpmode; // Specified jump size } t_asmoperand; static char *asmcmd; // Pointer to 0-terminated source line static int scan; // Type of last scanned element static int prio; // Priority of operation (0: highest) static char sdata[TEXTLEN]; // Last scanned name (depends on type) static long idata; // Last scanned value static long double fdata; // Floating-point number static char *asmerror; // Explanation of last error, or NULL // Simple and slightly recursive scanner shared by Assemble(). The scanner is // straightforward and ineffective, but high speed is not a must here. As // input, it uses global pointer to source line asmcmd. On exit, it fills in // global variables scan, prio, sdata, idata and/or fdata. If some error is // detected, asmerror points to error message, otherwise asmerror remains // unchanged. static void Scanasm(int mode) { int i,j,base,maxdigit; long decimal,hex; long double floating,divisor; char s[TEXTLEN],*pcmd; sdata[0]='\0'; idata=0; if (asmcmd==NULL) { asmerror="NULL input line"; scan=SCAN_ERR; return; }; while (*asmcmd==' ' || *asmcmd=='\t') asmcmd++; // Skip leading spaces if (*asmcmd=='\0' || *asmcmd==';') { scan=SCAN_EOL; return; }; // Empty line if (isalpha(*asmcmd) || *asmcmd=='_' || *asmcmd=='@') { sdata[0]=*asmcmd++; i=1; // Some keyword or identifier while ((isalnum(*asmcmd) || *asmcmd=='_' || *asmcmd=='@') && i<sizeof(sdata)) sdata[i++]=*asmcmd++; if (i>=sizeof(sdata)) { asmerror="Too long identifier"; scan=SCAN_ERR; return; }; sdata[i]='\0'; while (*asmcmd==' ' || *asmcmd=='\t') asmcmd++; // Skip trailing spaces strcpy(s,sdata); strupr(s); for (j=0; j<=8; j++) { // j==8 means "any register" if (strcmp(s,regname[0][j])!=0) continue; idata=j; scan=SCAN_REG8; // 8-bit register return; }; for (j=0; j<=8; j++) { if (strcmp(s,regname[1][j])!=0) continue; idata=j; scan=SCAN_REG16; // 16-bit register return; }; for (j=0; j<=8; j++) { if (strcmp(s,regname[2][j])!=0) continue; idata=j; scan=SCAN_REG32; // 32-bit register return; }; for (j=0; j<6; j++) { if (strcmp(s,segname[j])!=0) continue; idata=j; scan=SCAN_SEG; // Segment register while (*asmcmd==' ' || *asmcmd=='\t') asmcmd++; // Skip trailing spaces return; }; if (strcmp(s,"ST")==0) { pcmd=asmcmd; Scanasm(SA_NAME); // FPU register if (scan!=SCAN_SYMB || idata!='(') { asmcmd=pcmd; // Undo last scan