www.pudn.com > vbakey.zip > vbakey.cpp

#include  
#include  
#include  
#pragma hdrstop 
#include  
 
#define BLOCK_SIZE 32768 
 
//--------------------------------------------------------------------------- 
 
int memstr(const char *buf, const char *s, size_t size) 
{ 
   int        off; 
   const char *s_temp; 
 
   //return -1; 
   if(!buf || !s || !(*s)) return -1; 
 
   for(off = 0; off < size; off++) 
   { 
      for(s_temp = s; *s_temp != 0 && *buf == *s_temp; buf++, s_temp++) 
      { 
         off++; 
         if(off >= size) return -1; 
      } 
      if((*(buf - 1) == *(s_temp - 1)) && *s_temp == 0) return off; 
      buf++; 
   } 
   return -1; 
} 
 
LPSTR findEncryptPass(const char *filename) 
{ 
   FILE   *prot_file; 
   char   *buff = 0, *s; 
   size_t rc; 
   int    off; 
 
   prot_file = fopen(filename, "rb"); 
   if(!prot_file) return 0; 
   buff = (char *)malloc(BLOCK_SIZE); 
   if(!buff) return 0; 
   do 
   { 
      rc = fread(buff, 1, BLOCK_SIZE, prot_file); 
      if(!rc) break; 
      off = memstr(buff, "DPB=\"", BLOCK_SIZE); 
      if(off < 0) 
      { 
         if(rc < BLOCK_SIZE) break; 
         fseek(prot_file, -32, SEEK_CUR); 
         continue; 
      } 
      fseek(prot_file, off - rc, SEEK_CUR); 
      rc = fread(buff, 1, BLOCK_SIZE, prot_file); 
      if(!rc) break; 
      s = strchr(buff, '\"'); 
      *s = 0; 
      return buff; 
   } while(!feof(prot_file)); 
   free(buff); 
   return 0; 
} 
 
void decryptPassword(const char *encrypt_pass, char *s) 
{ 
   char str[128], ch; 
   char hs[] = { 0, 0, 0 }; 
   int  v1, v2, i, l; 
   int  begin_found = 0; 
 
   *s = 0; 
 
   for(i = 0; encrypt_pass[i*2]; i++) 
   { 
      hs[0] = encrypt_pass[i*2]; hs[1] = encrypt_pass[i*2+1]; 
      v1 = strtol(hs, 0, 16); 
      hs[0] = encrypt_pass[i*2+4]; hs[1] = encrypt_pass[i*2+5]; 
      v2 = strtol(hs, 0, 16); 
      if(!begin_found) 
      { 
         if(v1 == v2) begin_found = 1; 
      } 
      else 
      { 
         if(v1 != v2) 
            begin_found = 0; 
         else 
         { 
            i += 3; 
            break; 
         } 
      } 
   } 
 
   if(!begin_found) return; 
 
   for(ch = 0, l = 0; encrypt_pass[i*2+2]; i++, l++) 
   { 
      hs[0] = encrypt_pass[(i-2)*2]; hs[1] = encrypt_pass[(i-2)*2+1]; 
      v1 = strtol(hs, 0, 16); 
      hs[0] = encrypt_pass[i*2]; hs[1] = encrypt_pass[i*2+1]; 
      v2 = strtol(hs, 0, 16); 
      ch = (ch + (char)v1) ^ (char)v2; 
      str[l] = ch; 
   } 
   str[l] = 0; 
   CharToOem(str, s); 
} 
 
#pragma argsused 
int main(int argc, char **argv) 
{ 
   char s[128]; 
   char *encrypt_pass_str; 
 
   if(argc < 2) 
   { 
      printf("Usage: vbakey.exe filename\n"); 
      return 1; 
   } 
 
   if(!(encrypt_pass_str = findEncryptPass(argv[1]))) 
   { 
      //CharToOem("Пароль не найден\n", s); 
      printf("Password not found\n"); 
      return 1; 
   } 
 
   decryptPassword(encrypt_pass_str, s); 
   printf("File password: %s\n", s); 
   free(encrypt_pass_str); 
   printf("Press any key for continue ... \n"); 
   getch(); 
   return 0; 
}